Merge tag 'for-5.3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs updates from David Sterba:
 "Highlights:

   - chunks that have been trimmed and unchanged since last mount are
     tracked and skipped on repeated trims

   - use hw assissed crc32c on more arches, speedups if native
     instructions or optimized implementation is available

   - the RAID56 incompat bit is automatically removed when the last
     block group of that type is removed

  Fixes:

   - fsync fix for reflink on NODATACOW files that could lead to ENOSPC

   - fix data loss after inode eviction, renaming it, and fsync it

   - fix fsync not persisting dentry deletions due to inode evictions

   - update ctime/mtime/iversion after hole punching

   - fix compression type validation (reported by KASAN)

   - send won't be allowed to start when relocation is in progress, this
     can cause spurious errors or produce incorrect send stream

  Core:

   - new tracepoints for space update

   - tree-checker: better check for end of extents for some tree items

   - preparatory work for more checksum algorithms

   - run delayed iput at unlink time and don't push the work to cleaner
     thread where it's not properly throttled

   - wrap block mapping to structures and helpers, base for further
     refactoring

   - split large files, part 1:
       - space info handling
       - block group reservations
       - delayed refs
       - delayed allocation

   - other cleanups and refactoring"

* tag 'for-5.3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (103 commits)
  btrfs: fix memory leak of path on error return path
  btrfs: move the subvolume reservation stuff out of extent-tree.c
  btrfs: migrate the delalloc space stuff to it's own home
  btrfs: migrate btrfs_trans_release_chunk_metadata
  btrfs: migrate the delayed refs rsv code
  btrfs: Evaluate io_tree in find_lock_delalloc_range()
  btrfs: migrate the global_block_rsv helpers to block-rsv.c
  btrfs: migrate the block-rsv code to block-rsv.c
  btrfs: stop using block_rsv_release_bytes everywhere
  btrfs: cleanup the target logic in __btrfs_block_rsv_release
  btrfs: export __btrfs_block_rsv_release
  btrfs: export btrfs_block_rsv_add_bytes
  btrfs: move btrfs_block_rsv definitions into it's own header
  btrfs: Simplify update of space_info in __reserve_metadata_bytes()
  btrfs: unexport can_overcommit
  btrfs: move reserve_metadata_bytes and supporting code to space-info.c
  btrfs: move dump_space_info to space-info.c
  btrfs: export block_rsv_use_bytes
  btrfs: move btrfs_space_info_add_*_bytes to space-info.c
  btrfs: move the space info update macro to space-info.h
  ...

50 files changed, 3786 insertions, 3124 deletions

diff --git a/fs/btrfs/Kconfig b/fs/btrfs/Kconfig
index 23537bc8c827..212b4a854f2c 100644
--- a/fs/btrfs/Kconfig
+++ b/fs/btrfs/Kconfig
@@ -2,7 +2,8 @@
 
 config BTRFS_FS
 	tristate "Btrfs filesystem support"
-	select LIBCRC32C
+	select CRYPTO
+	select CRYPTO_CRC32C
 	select ZLIB_INFLATE
 	select ZLIB_DEFLATE
 	select LZO_COMPRESS
diff --git a/fs/btrfs/Makefile b/fs/btrfs/Makefile
index ca693dd554e9..76a843198bcb 100644
--- a/fs/btrfs/Makefile
+++ b/fs/btrfs/Makefile
@@ -10,7 +10,8 @@ btrfs-y += super.o ctree.o extent-tree.o print-tree.o root-tree.o dir-item.o \
 	   export.o tree-log.o free-space-cache.o zlib.o lzo.o zstd.o \
 	   compression.o delayed-ref.o relocation.o delayed-inode.o scrub.o \
 	   reada.o backref.o ulist.o qgroup.o send.o dev-replace.o raid56.o \
-	   uuid-tree.o props.o free-space-tree.o tree-checker.o
+	   uuid-tree.o props.o free-space-tree.o tree-checker.o space-info.o \
+	   block-rsv.o delalloc-space.o
 
 btrfs-$(CONFIG_BTRFS_FS_POSIX_ACL) += acl.o
 btrfs-$(CONFIG_BTRFS_FS_CHECK_INTEGRITY) += check-integrity.o
diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c
index 982152d3f920..89116afda7a2 100644
--- a/fs/btrfs/backref.c
+++ b/fs/btrfs/backref.c
@@ -1465,12 +1465,11 @@ int btrfs_find_all_roots(struct btrfs_trans_handle *trans,
  *
  * Return: 0 if extent is not shared, 1 if it is shared, < 0 on error.
  */
-int btrfs_check_shared(struct btrfs_root *root, u64 inum, u64 bytenr)
+int btrfs_check_shared(struct btrfs_root *root, u64 inum, u64 bytenr,
+		struct ulist *roots, struct ulist *tmp)
 {
 	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct btrfs_trans_handle *trans;
-	struct ulist *tmp = NULL;
-	struct ulist *roots = NULL;
 	struct ulist_iterator uiter;
 	struct ulist_node *node;
 	struct seq_list elem = SEQ_LIST_INIT(elem);
@@ -1481,12 +1480,8 @@ int btrfs_check_shared(struct btrfs_root *root, u64 inum, u64 bytenr)
 		.share_count = 0,
 	};
 
-	tmp = ulist_alloc(GFP_NOFS);
-	roots = ulist_alloc(GFP_NOFS);
-	if (!tmp || !roots) {
-		ret = -ENOMEM;
-		goto out;
-	}
+	ulist_init(roots);
+	ulist_init(tmp);
 
 	trans = btrfs_attach_transaction(root);
 	if (IS_ERR(trans)) {
@@ -1527,8 +1522,8 @@ int btrfs_check_shared(struct btrfs_root *root, u64 inum, u64 bytenr)
 		up_read(&fs_info->commit_root_sem);
 	}
 out:
-	ulist_free(tmp);
-	ulist_free(roots);
+	ulist_release(roots);
+	ulist_release(tmp);
 	return ret;
 }
 
diff --git a/fs/btrfs/backref.h b/fs/btrfs/backref.h
index 54d58988483a..777f61dc081e 100644
--- a/fs/btrfs/backref.h
+++ b/fs/btrfs/backref.h
@@ -57,7 +57,8 @@ int btrfs_find_one_extref(struct btrfs_root *root, u64 inode_objectid,
 			  u64 start_off, struct btrfs_path *path,
 			  struct btrfs_inode_extref **ret_extref,
 			  u64 *found_off);
-int btrfs_check_shared(struct btrfs_root *root, u64 inum, u64 bytenr);
+int btrfs_check_shared(struct btrfs_root *root, u64 inum, u64 bytenr,
+		struct ulist *roots, struct ulist *tmp_ulist);
 
 int __init btrfs_prelim_ref_init(void);
 void __cold btrfs_prelim_ref_exit(void);
diff --git a/fs/btrfs/block-rsv.c b/fs/btrfs/block-rsv.c
new file mode 100644
index 000000000000..698470b9f32d
--- /dev/null
+++ b/fs/btrfs/block-rsv.c
@@ -0,0 +1,425 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include "ctree.h"
+#include "block-rsv.h"
+#include "space-info.h"
+#include "math.h"
+#include "transaction.h"
+
+static u64 block_rsv_release_bytes(struct btrfs_fs_info *fs_info,
+				    struct btrfs_block_rsv *block_rsv,
+				    struct btrfs_block_rsv *dest, u64 num_bytes,
+				    u64 *qgroup_to_release_ret)
+{
+	struct btrfs_space_info *space_info = block_rsv->space_info;
+	u64 qgroup_to_release = 0;
+	u64 ret;
+
+	spin_lock(&block_rsv->lock);
+	if (num_bytes == (u64)-1) {
+		num_bytes = block_rsv->size;
+		qgroup_to_release = block_rsv->qgroup_rsv_size;
+	}
+	block_rsv->size -= num_bytes;
+	if (block_rsv->reserved >= block_rsv->size) {
+		num_bytes = block_rsv->reserved - block_rsv->size;
+		block_rsv->reserved = block_rsv->size;
+		block_rsv->full = 1;
+	} else {
+		num_bytes = 0;
+	}
+	if (block_rsv->qgroup_rsv_reserved >= block_rsv->qgroup_rsv_size) {
+		qgroup_to_release = block_rsv->qgroup_rsv_reserved -
+				    block_rsv->qgroup_rsv_size;
+		block_rsv->qgroup_rsv_reserved = block_rsv->qgroup_rsv_size;
+	} else {
+		qgroup_to_release = 0;
+	}
+	spin_unlock(&block_rsv->lock);
+
+	ret = num_bytes;
+	if (num_bytes > 0) {
+		if (dest) {
+			spin_lock(&dest->lock);
+			if (!dest->full) {
+				u64 bytes_to_add;
+
+				bytes_to_add = dest->size - dest->reserved;
+				bytes_to_add = min(num_bytes, bytes_to_add);
+				dest->reserved += bytes_to_add;
+				if (dest->reserved >= dest->size)
+					dest->full = 1;
+				num_bytes -= bytes_to_add;
+			}
+			spin_unlock(&dest->lock);
+		}
+		if (num_bytes)
+			btrfs_space_info_add_old_bytes(fs_info, space_info,
+						       num_bytes);
+	}
+	if (qgroup_to_release_ret)
+		*qgroup_to_release_ret = qgroup_to_release;
+	return ret;
+}
+
+int btrfs_block_rsv_migrate(struct btrfs_block_rsv *src,
+			    struct btrfs_block_rsv *dst, u64 num_bytes,
+			    bool update_size)
+{
+	int ret;
+
+	ret = btrfs_block_rsv_use_bytes(src, num_bytes);
+	if (ret)
+		return ret;
+
+	btrfs_block_rsv_add_bytes(dst, num_bytes, update_size);
+	return 0;
+}
+
+void btrfs_init_block_rsv(struct btrfs_block_rsv *rsv, unsigned short type)
+{
+	memset(rsv, 0, sizeof(*rsv));
+	spin_lock_init(&rsv->lock);
+	rsv->type = type;
+}
+
+void btrfs_init_metadata_block_rsv(struct btrfs_fs_info *fs_info,
+				   struct btrfs_block_rsv *rsv,
+				   unsigned short type)
+{
+	btrfs_init_block_rsv(rsv, type);
+	rsv->space_info = btrfs_find_space_info(fs_info,
+					    BTRFS_BLOCK_GROUP_METADATA);
+}
+
+struct btrfs_block_rsv *btrfs_alloc_block_rsv(struct btrfs_fs_info *fs_info,
+					      unsigned short type)
+{
+	struct btrfs_block_rsv *block_rsv;
+
+	block_rsv = kmalloc(sizeof(*block_rsv), GFP_NOFS);
+	if (!block_rsv)
+		return NULL;
+
+	btrfs_init_metadata_block_rsv(fs_info, block_rsv, type);
+	return block_rsv;
+}
+
+void btrfs_free_block_rsv(struct btrfs_fs_info *fs_info,
+			  struct btrfs_block_rsv *rsv)
+{
+	if (!rsv)
+		return;
+	btrfs_block_rsv_release(fs_info, rsv, (u64)-1);
+	kfree(rsv);
+}
+
+int btrfs_block_rsv_add(struct btrfs_root *root,
+			struct btrfs_block_rsv *block_rsv, u64 num_bytes,
+			enum btrfs_reserve_flush_enum flush)
+{
+	int ret;
+
+	if (num_bytes == 0)
+		return 0;
+
+	ret = btrfs_reserve_metadata_bytes(root, block_rsv, num_bytes, flush);
+	if (!ret)
+		btrfs_block_rsv_add_bytes(block_rsv, num_bytes, true);
+
+	return ret;
+}
+
+int btrfs_block_rsv_check(struct btrfs_block_rsv *block_rsv, int min_factor)
+{
+	u64 num_bytes = 0;
+	int ret = -ENOSPC;
+
+	if (!block_rsv)
+		return 0;
+
+	spin_lock(&block_rsv->lock);
+	num_bytes = div_factor(block_rsv->size, min_factor);
+	if (block_rsv->reserved >= num_bytes)
+		ret = 0;
+	spin_unlock(&block_rsv->lock);
+
+	return ret;
+}
+
+int btrfs_block_rsv_refill(struct btrfs_root *root,
+			   struct btrfs_block_rsv *block_rsv, u64 min_reserved,
+			   enum btrfs_reserve_flush_enum flush)
+{
+	u64 num_bytes = 0;
+	int ret = -ENOSPC;
+
+	if (!block_rsv)
+		return 0;
+
+	spin_lock(&block_rsv->lock);
+	num_bytes = min_reserved;
+	if (block_rsv->reserved >= num_bytes)
+		ret = 0;
+	else
+		num_bytes -= block_rsv->reserved;
+	spin_unlock(&block_rsv->lock);
+
+	if (!ret)
+		return 0;
+
+	ret = btrfs_reserve_metadata_bytes(root, block_rsv, num_bytes, flush);
+	if (!ret) {
+		btrfs_block_rsv_add_bytes(block_rsv, num_bytes, false);
+		return 0;
+	}
+
+	return ret;
+}
+
+u64 __btrfs_block_rsv_release(struct btrfs_fs_info *fs_info,
+			      struct btrfs_block_rsv *block_rsv,
+			      u64 num_bytes, u64 *qgroup_to_release)
+{
+	struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
+	struct btrfs_block_rsv *delayed_rsv = &fs_info->delayed_refs_rsv;
+	struct btrfs_block_rsv *target = NULL;
+
+	/*
+	 * If we are the delayed_rsv then push to the global rsv, otherwise dump
+	 * into the delayed rsv if it is not full.
+	 */
+	if (block_rsv == delayed_rsv)
+		target = global_rsv;
+	else if (block_rsv != global_rsv && !delayed_rsv->full)
+		target = delayed_rsv;
+
+	if (target && block_rsv->space_info != target->space_info)
+		target = NULL;
+
+	return block_rsv_release_bytes(fs_info, block_rsv, target, num_bytes,
+				       qgroup_to_release);
+}
+
+int btrfs_block_rsv_use_bytes(struct btrfs_block_rsv *block_rsv, u64 num_bytes)
+{
+	int ret = -ENOSPC;
+
+	spin_lock(&block_rsv->lock);
+	if (block_rsv->reserved >= num_bytes) {
+		block_rsv->reserved -= num_bytes;
+		if (block_rsv->reserved < block_rsv->size)
+			block_rsv->full = 0;
+		ret = 0;
+	}
+	spin_unlock(&block_rsv->lock);
+	return ret;
+}
+
+void btrfs_block_rsv_add_bytes(struct btrfs_block_rsv *block_rsv,
+			       u64 num_bytes, bool update_size)
+{
+	spin_lock(&block_rsv->lock);
+	block_rsv->reserved += num_bytes;
+	if (update_size)
+		block_rsv->size += num_bytes;
+	else if (block_rsv->reserved >= block_rsv->size)
+		block_rsv->full = 1;
+	spin_unlock(&block_rsv->lock);
+}
+
+int btrfs_cond_migrate_bytes(struct btrfs_fs_info *fs_info,
+			     struct btrfs_block_rsv *dest, u64 num_bytes,
+			     int min_factor)
+{
+	struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
+	u64 min_bytes;
+
+	if (global_rsv->space_info != dest->space_info)
+		return -ENOSPC;
+
+	spin_lock(&global_rsv->lock);
+	min_bytes = div_factor(global_rsv->size, min_factor);
+	if (global_rsv->reserved < min_bytes + num_bytes) {
+		spin_unlock(&global_rsv->lock);
+		return -ENOSPC;
+	}
+	global_rsv->reserved -= num_bytes;
+	if (global_rsv->reserved < global_rsv->size)
+		global_rsv->full = 0;
+	spin_unlock(&global_rsv->lock);
+
+	btrfs_block_rsv_add_bytes(dest, num_bytes, true);
+	return 0;
+}
+
+void btrfs_update_global_block_rsv(struct btrfs_fs_info *fs_info)
+{
+	struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
+	struct btrfs_space_info *sinfo = block_rsv->space_info;
+	u64 num_bytes;
+
+	/*
+	 * The global block rsv is based on the size of the extent tree, the
+	 * checksum tree and the root tree.  If the fs is empty we want to set
+	 * it to a minimal amount for safety.
+	 */
+	num_bytes = btrfs_root_used(&fs_info->extent_root->root_item) +
+		btrfs_root_used(&fs_info->csum_root->root_item) +
+		btrfs_root_used(&fs_info->tree_root->root_item);
+	num_bytes = max_t(u64, num_bytes, SZ_16M);
+
+	spin_lock(&sinfo->lock);
+	spin_lock(&block_rsv->lock);
+
+	block_rsv->size = min_t(u64, num_bytes, SZ_512M);
+
+	if (block_rsv->reserved < block_rsv->size) {
+		num_bytes = btrfs_space_info_used(sinfo, true);
+		if (sinfo->total_bytes > num_bytes) {
+			num_bytes = sinfo->total_bytes - num_bytes;
+			num_bytes = min(num_bytes,
+					block_rsv->size - block_rsv->reserved);
+			block_rsv->reserved += num_bytes;
+			btrfs_space_info_update_bytes_may_use(fs_info, sinfo,
+							      num_bytes);
+			trace_btrfs_space_reservation(fs_info, "space_info",
+						      sinfo->flags, num_bytes,
+						      1);
+		}
+	} else if (block_rsv->reserved > block_rsv->size) {
+		num_bytes = block_rsv->reserved - block_rsv->size;
+		btrfs_space_info_update_bytes_may_use(fs_info, sinfo,
+						      -num_bytes);
+		trace_btrfs_space_reservation(fs_info, "space_info",
+				      sinfo->flags, num_bytes, 0);
+		block_rsv->reserved = block_rsv->size;
+	}
+
+	if (block_rsv->reserved == block_rsv->size)
+		block_rsv->full = 1;
+	else
+		block_rsv->full = 0;
+
+	spin_unlock(&block_rsv->lock);
+	spin_unlock(&sinfo->lock);
+}
+
+void btrfs_init_global_block_rsv(struct btrfs_fs_info *fs_info)
+{
+	struct btrfs_space_info *space_info;
+
+	space_info = btrfs_find_space_info(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
+	fs_info->chunk_block_rsv.space_info = space_info;
+
+	space_info = btrfs_find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
+	fs_info->global_block_rsv.space_info = space_info;
+	fs_info->trans_block_rsv.space_info = space_info;
+	fs_info->empty_block_rsv.space_info = space_info;
+	fs_info->delayed_block_rsv.space_info = space_info;
+	fs_info->delayed_refs_rsv.space_info = space_info;
+
+	fs_info->extent_root->block_rsv = &fs_info->delayed_refs_rsv;
+	fs_info->csum_root->block_rsv = &fs_info->delayed_refs_rsv;
+	fs_info->dev_root->block_rsv = &fs_info->global_block_rsv;
+	fs_info->tree_root->block_rsv = &fs_info->global_block_rsv;
+	if (fs_info->quota_root)
+		fs_info->quota_root->block_rsv = &fs_info->global_block_rsv;
+	fs_info->chunk_root->block_rsv = &fs_info->chunk_block_rsv;
+
+	btrfs_update_global_block_rsv(fs_info);
+}
+
+void btrfs_release_global_block_rsv(struct btrfs_fs_info *fs_info)
+{
+	btrfs_block_rsv_release(fs_info, &fs_info->global_block_rsv, (u64)-1);
+	WARN_ON(fs_info->trans_block_rsv.size > 0);
+	WARN_ON(fs_info->trans_block_rsv.reserved > 0);
+	WARN_ON(fs_info->chunk_block_rsv.size > 0);
+	WARN_ON(fs_info->chunk_block_rsv.reserved > 0);
+	WARN_ON(fs_info->delayed_block_rsv.size > 0);
+	WARN_ON(fs_info->delayed_block_rsv.reserved > 0);
+	WARN_ON(fs_info->delayed_refs_rsv.reserved > 0);
+	WARN_ON(fs_info->delayed_refs_rsv.size > 0);
+}
+
+static struct btrfs_block_rsv *get_block_rsv(
+					const struct btrfs_trans_handle *trans,
+					const struct btrfs_root *root)
+{
+	struct btrfs_fs_info *fs_info = root->fs_info;
+	struct btrfs_block_rsv *block_rsv = NULL;
+
+	if (test_bit(BTRFS_ROOT_REF_COWS, &root->state) ||
+	    (root == fs_info->csum_root && trans->adding_csums) ||
+	    (root == fs_info->uuid_root))
+		block_rsv = trans->block_rsv;
+
+	if (!block_rsv)
+		block_rsv = root->block_rsv;
+
+	if (!block_rsv)
+		block_rsv = &fs_info->empty_block_rsv;
+
+	return block_rsv;
+}
+
+struct btrfs_block_rsv *btrfs_use_block_rsv(struct btrfs_trans_handle *trans,
+					    struct btrfs_root *root,
+					    u32 blocksize)
+{
+	struct btrfs_fs_info *fs_info = root->fs_info;
+	struct btrfs_block_rsv *block_rsv;
+	struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
+	int ret;
+	bool global_updated = false;
+
+	block_rsv = get_block_rsv(trans, root);
+
+	if (unlikely(block_rsv->size == 0))
+		goto try_reserve;
+again:
+	ret = btrfs_block_rsv_use_bytes(block_rsv, blocksize);
+	if (!ret)
+		return block_rsv;
+
+	if (block_rsv->failfast)
+		return ERR_PTR(ret);
+
+	if (block_rsv->type == BTRFS_BLOCK_RSV_GLOBAL && !global_updated) {
+		global_updated = true;
+		btrfs_update_global_block_rsv(fs_info);
+		goto again;
+	}
+
+	/*
+	 * The global reserve still exists to save us from ourselves, so don't
+	 * warn_on if we are short on our delayed refs reserve.
+	 */
+	if (block_rsv->type != BTRFS_BLOCK_RSV_DELREFS &&
+	    btrfs_test_opt(fs_info, ENOSPC_DEBUG)) {
+		static DEFINE_RATELIMIT_STATE(_rs,
+				DEFAULT_RATELIMIT_INTERVAL * 10,
+				/*DEFAULT_RATELIMIT_BURST*/ 1);
+		if (__ratelimit(&_rs))
+			WARN(1, KERN_DEBUG
+				"BTRFS: block rsv returned %d\n", ret);
+	}
+try_reserve:
+	ret = btrfs_reserve_metadata_bytes(root, block_rsv, blocksize,
+					   BTRFS_RESERVE_NO_FLUSH);
+	if (!ret)
+		return block_rsv;
+	/*
+	 * If we couldn't reserve metadata bytes try and use some from
+	 * the global reserve if its space type is the same as the global
+	 * reservation.
+	 */
+	if (block_rsv->type != BTRFS_BLOCK_RSV_GLOBAL &&
+	    block_rsv->space_info == global_rsv->space_info) {
+		ret = btrfs_block_rsv_use_bytes(global_rsv, blocksize);
+		if (!ret)
+			return global_rsv;
+	}
+	return ERR_PTR(ret);
+}
diff --git a/fs/btrfs/block-rsv.h b/fs/btrfs/block-rsv.h
new file mode 100644
index 000000000000..d1428bb73fc5
--- /dev/null
+++ b/fs/btrfs/block-rsv.h
@@ -0,0 +1,101 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef BTRFS_BLOCK_RSV_H
+#define BTRFS_BLOCK_RSV_H
+
+struct btrfs_trans_handle;
+enum btrfs_reserve_flush_enum;
+
+/*
+ * Types of block reserves
+ */
+enum {
+	BTRFS_BLOCK_RSV_GLOBAL,
+	BTRFS_BLOCK_RSV_DELALLOC,
+	BTRFS_BLOCK_RSV_TRANS,
+	BTRFS_BLOCK_RSV_CHUNK,
+	BTRFS_BLOCK_RSV_DELOPS,
+	BTRFS_BLOCK_RSV_DELREFS,
+	BTRFS_BLOCK_RSV_EMPTY,
+	BTRFS_BLOCK_RSV_TEMP,
+};
+
+struct btrfs_block_rsv {
+	u64 size;
+	u64 reserved;
+	struct btrfs_space_info *space_info;
+	spinlock_t lock;
+	unsigned short full;
+	unsigned short type;
+	unsigned short failfast;
+
+	/*
+	 * Qgroup equivalent for @size @reserved
+	 *
+	 * Unlike normal @size/@reserved for inode rsv, qgroup doesn't care
+	 * about things like csum size nor how many tree blocks it will need to
+	 * reserve.
+	 *
+	 * Qgroup cares more about net change of the extent usage.
+	 *
+	 * So for one newly inserted file extent, in worst case it will cause
+	 * leaf split and level increase, nodesize for each file extent is
+	 * already too much.
+	 *
+	 * In short, qgroup_size/reserved is the upper limit of possible needed
+	 * qgroup metadata reservation.
+	 */
+	u64 qgroup_rsv_size;
+	u64 qgroup_rsv_reserved;
+};
+
+void btrfs_init_block_rsv(struct btrfs_block_rsv *rsv, unsigned short type);
+struct btrfs_block_rsv *btrfs_alloc_block_rsv(struct btrfs_fs_info *fs_info,
+					      unsigned short type);
+void btrfs_init_metadata_block_rsv(struct btrfs_fs_info *fs_info,
+				   struct btrfs_block_rsv *rsv,
+				   unsigned short type);
+void btrfs_free_block_rsv(struct btrfs_fs_info *fs_info,
+			  struct btrfs_block_rsv *rsv);
+int btrfs_block_rsv_add(struct btrfs_root *root,
+			struct btrfs_block_rsv *block_rsv, u64 num_bytes,
+			enum btrfs_reserve_flush_enum flush);
+int btrfs_block_rsv_check(struct btrfs_block_rsv *block_rsv, int min_factor);
+int btrfs_block_rsv_refill(struct btrfs_root *root,
+			   struct btrfs_block_rsv *block_rsv, u64 min_reserved,
+			   enum btrfs_reserve_flush_enum flush);
+int btrfs_block_rsv_migrate(struct btrfs_block_rsv *src_rsv,
+			    struct btrfs_block_rsv *dst_rsv, u64 num_bytes,
+			    bool update_size);
+int btrfs_block_rsv_use_bytes(struct btrfs_block_rsv *block_rsv, u64 num_bytes);
+int btrfs_cond_migrate_bytes(struct btrfs_fs_info *fs_info,
+			     struct btrfs_block_rsv *dest, u64 num_bytes,
+			     int min_factor);
+void btrfs_block_rsv_add_bytes(struct btrfs_block_rsv *block_rsv,
+			       u64 num_bytes, bool update_size);
+u64 __btrfs_block_rsv_release(struct btrfs_fs_info *fs_info,
+			      struct btrfs_block_rsv *block_rsv,
+			      u64 num_bytes, u64 *qgroup_to_release);
+void btrfs_update_global_block_rsv(struct btrfs_fs_info *fs_info);
+void btrfs_init_global_block_rsv(struct btrfs_fs_info *fs_info);
+void btrfs_release_global_block_rsv(struct btrfs_fs_info *fs_info);
+struct btrfs_block_rsv *btrfs_use_block_rsv(struct btrfs_trans_handle *trans,
+					    struct btrfs_root *root,
+					    u32 blocksize);
+
+static inline void btrfs_block_rsv_release(struct btrfs_fs_info *fs_info,
+					   struct btrfs_block_rsv *block_rsv,
+					   u64 num_bytes)
+{
+	__btrfs_block_rsv_release(fs_info, block_rsv, num_bytes, NULL);
+}
+
+static inline void btrfs_unuse_block_rsv(struct btrfs_fs_info *fs_info,
+					 struct btrfs_block_rsv *block_rsv,
+					 u32 blocksize)
+{
+	btrfs_block_rsv_add_bytes(block_rsv, blocksize, false);
+	btrfs_block_rsv_release(fs_info, block_rsv, 0);
+}
+
+#endif /* BTRFS_BLOCK_RSV_H */
diff --git a/fs/btrfs/btrfs_inode.h b/fs/btrfs/btrfs_inode.h
index d5b438706b77..f853835c409c 100644
--- a/fs/btrfs/btrfs_inode.h
+++ b/fs/btrfs/btrfs_inode.h
@@ -337,22 +337,34 @@ static inline void btrfs_inode_resume_unlocked_dio(struct btrfs_inode *inode)
 	clear_bit(BTRFS_INODE_READDIO_NEED_LOCK, &inode->runtime_flags);
 }
 
+/* Array of bytes with variable length, hexadecimal format 0x1234 */
+#define CSUM_FMT				"0x%*phN"
+#define CSUM_FMT_VALUE(size, bytes)		size, bytes
+
 static inline void btrfs_print_data_csum_error(struct btrfs_inode *inode,
-		u64 logical_start, u32 csum, u32 csum_expected, int mirror_num)
+		u64 logical_start, u8 *csum, u8 *csum_expected, int mirror_num)
 {
 	struct btrfs_root *root = inode->root;
+	struct btrfs_super_block *sb = root->fs_info->super_copy;
+	const u16 csum_size = btrfs_super_csum_size(sb);
 
 	/* Output minus objectid, which is more meaningful */
 	if (root->root_key.objectid >= BTRFS_LAST_FREE_OBJECTID)
 		btrfs_warn_rl(root->fs_info,
-	"csum failed root %lld ino %lld off %llu csum 0x%08x expected csum 0x%08x mirror %d",
+"csum failed root %lld ino %lld off %llu csum " CSUM_FMT " expected csum " CSUM_FMT " mirror %d",
 			root->root_key.objectid, btrfs_ino(inode),
-			logical_start, csum, csum_expected, mirror_num);
+			logical_start,
+			CSUM_FMT_VALUE(csum_size, csum),
+			CSUM_FMT_VALUE(csum_size, csum_expected),
+			mirror_num);
 	else
 		btrfs_warn_rl(root->fs_info,
-	"csum failed root %llu ino %llu off %llu csum 0x%08x expected csum 0x%08x mirror %d",
+"csum failed root %llu ino %llu off %llu csum " CSUM_FMT " expected csum " CSUM_FMT " mirror %d",
 			root->root_key.objectid, btrfs_ino(inode),
-			logical_start, csum, csum_expected, mirror_num);
+			logical_start,
+			CSUM_FMT_VALUE(csum_size, csum),
+			CSUM_FMT_VALUE(csum_size, csum_expected),
+			mirror_num);
 }
 
 #endif
diff --git a/fs/btrfs/check-integrity.c b/fs/btrfs/check-integrity.c
index b0c8094528d1..81a9731959a9 100644
--- a/fs/btrfs/check-integrity.c
+++ b/fs/btrfs/check-integrity.c
@@ -83,7 +83,7 @@
 #include <linux/blkdev.h>
 #include <linux/mm.h>
 #include <linux/string.h>
-#include <linux/crc32c.h>
+#include <crypto/hash.h>
 #include "ctree.h"
 #include "disk-io.h"
 #include "transaction.h"
@@ -1710,9 +1710,9 @@ static int btrfsic_test_for_metadata(struct btrfsic_state *state,
 				     char **datav, unsigned int num_pages)
 {
 	struct btrfs_fs_info *fs_info = state->fs_info;
+	SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
 	struct btrfs_header *h;
 	u8 csum[BTRFS_CSUM_SIZE];
-	u32 crc = ~(u32)0;
 	unsigned int i;
 
 	if (num_pages * PAGE_SIZE < state->metablock_size)
@@ -1723,14 +1723,17 @@ static int btrfsic_test_for_metadata(struct btrfsic_state *state,
 	if (memcmp(h->fsid, fs_info->fs_devices->fsid, BTRFS_FSID_SIZE))
 		return 1;
 
+	shash->tfm = fs_info->csum_shash;
+	crypto_shash_init(shash);
+
 	for (i = 0; i < num_pages; i++) {
 		u8 *data = i ? datav[i] : (datav[i] + BTRFS_CSUM_SIZE);
 		size_t sublen = i ? PAGE_SIZE :
 				    (PAGE_SIZE - BTRFS_CSUM_SIZE);
 
-		crc = crc32c(crc, data, sublen);
+		crypto_shash_update(shash, data, sublen);
 	}
-	btrfs_csum_final(crc, csum);
+	crypto_shash_final(shash, csum);
 	if (memcmp(csum, h->csum, state->csum_size))
 		return 1;
 
diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c
index 84dd4a8980c5..60c47b417a4b 100644
--- a/fs/btrfs/compression.c
+++ b/fs/btrfs/compression.c
@@ -17,6 +17,7 @@
 #include <linux/slab.h>
 #include <linux/sched/mm.h>
 #include <linux/log2.h>
+#include <crypto/hash.h>
 #include "ctree.h"
 #include "disk-io.h"
 #include "transaction.h"
@@ -42,6 +43,22 @@ const char* btrfs_compress_type2str(enum btrfs_compression_type type)
 	return NULL;
 }
 
+bool btrfs_compress_is_valid_type(const char *str, size_t len)
+{
+	int i;
+
+	for (i = 1; i < ARRAY_SIZE(btrfs_compress_types); i++) {
+		size_t comp_len = strlen(btrfs_compress_types[i]);
+
+		if (len < comp_len)
+			continue;
+
+		if (!strncmp(btrfs_compress_types[i], str, comp_len))
+			return true;
+	}
+	return false;
+}
+
 static int btrfs_decompress_bio(struct compressed_bio *cb);
 
 static inline int compressed_bio_size(struct btrfs_fs_info *fs_info,
@@ -57,32 +74,37 @@ static int check_compressed_csum(struct btrfs_inode *inode,
 				 struct compressed_bio *cb,
 				 u64 disk_start)
 {
+	struct btrfs_fs_info *fs_info = inode->root->fs_info;
+	SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
+	const u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
 	int ret;
 	struct page *page;
 	unsigned long i;
 	char *kaddr;
-	u32 csum;
-	u32 *cb_sum = &cb->sums;
+	u8 csum[BTRFS_CSUM_SIZE];
+	u8 *cb_sum = cb->sums;
 
 	if (inode->flags & BTRFS_INODE_NODATASUM)
 		return 0;
 
+	shash->tfm = fs_info->csum_shash;
+
 	for (i = 0; i < cb->nr_pages; i++) {
 		page = cb->compressed_pages[i];
-		csum = ~(u32)0;
 
+		crypto_shash_init(shash);
 		kaddr = kmap_atomic(page);
-		csum = btrfs_csum_data(kaddr, csum, PAGE_SIZE);
-		btrfs_csum_final(csum, (u8 *)&csum);
+		crypto_shash_update(shash, kaddr, PAGE_SIZE);
 		kunmap_atomic(kaddr);
+		crypto_shash_final(shash, (u8 *)&csum);
 
-		if (csum != *cb_sum) {
-			btrfs_print_data_csum_error(inode, disk_start, csum,
-					*cb_sum, cb->mirror_num);
+		if (memcmp(&csum, cb_sum, csum_size)) {
+			btrfs_print_data_csum_error(inode, disk_start,
+					csum, cb_sum, cb->mirror_num);
 			ret = -EIO;
 			goto fail;
 		}
-		cb_sum++;
+		cb_sum += csum_size;
 
 	}
 	ret = 0;
@@ -318,7 +340,8 @@ blk_status_t btrfs_submit_compressed_write(struct inode *inode, u64 start,
 
 	bdev = fs_info->fs_devices->latest_bdev;
 
-	bio = btrfs_bio_alloc(bdev, first_byte);
+	bio = btrfs_bio_alloc(first_byte);
+	bio_set_dev(bio, bdev);
 	bio->bi_opf = REQ_OP_WRITE | write_flags;
 	bio->bi_private = cb;
 	bio->bi_end_io = end_compressed_bio_write;
@@ -360,7 +383,8 @@ blk_status_t btrfs_submit_compressed_write(struct inode *inode, u64 start,
 				bio_endio(bio);
 			}
 
-			bio = btrfs_bio_alloc(bdev, first_byte);
+			bio = btrfs_bio_alloc(first_byte);
+			bio_set_dev(bio, bdev);
 			bio->bi_opf = REQ_OP_WRITE | write_flags;
 			bio->bi_private = cb;
 			bio->bi_end_io = end_compressed_bio_write;
@@ -536,7 +560,8 @@ blk_status_t btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
 	struct extent_map *em;
 	blk_status_t ret = BLK_STS_RESOURCE;
 	int faili = 0;
-	u32 *sums;
+	const u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
+	u8 *sums;
 
 	em_tree = &BTRFS_I(inode)->extent_tree;
 
@@ -558,7 +583,7 @@ blk_status_t btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
 	cb->errors = 0;
 	cb->inode = inode;
 	cb->mirror_num = mirror_num;
-	sums = &cb->sums;
+	sums = cb->sums;
 
 	cb->start = em->orig_start;
 	em_len = em->len;
@@ -597,7 +622,8 @@ blk_status_t btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
 	/* include any pages we added in add_ra-bio_pages */
 	cb->len = bio->bi_iter.bi_size;
 
-	comp_bio = btrfs_bio_alloc(bdev, cur_disk_byte);
+	comp_bio = btrfs_bio_alloc(cur_disk_byte);
+	bio_set_dev(comp_bio, bdev);
 	comp_bio->bi_opf = REQ_OP_READ;
 	comp_bio->bi_private = cb;
 	comp_bio->bi_end_io = end_compressed_bio_read;
@@ -617,6 +643,8 @@ blk_status_t btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
 		page->mapping = NULL;
 		if (submit || bio_add_page(comp_bio, page, PAGE_SIZE, 0) <
 		    PAGE_SIZE) {
+			unsigned int nr_sectors;
+
 			ret = btrfs_bio_wq_end_io(fs_info, comp_bio,
 						  BTRFS_WQ_ENDIO_DATA);
 			BUG_ON(ret); /* -ENOMEM */
@@ -634,8 +662,10 @@ blk_status_t btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
 							    sums);
 				BUG_ON(ret); /* -ENOMEM */
 			}
-			sums += DIV_ROUND_UP(comp_bio->bi_iter.bi_size,
-					     fs_info->sectorsize);
+
+			nr_sectors = DIV_ROUND_UP(comp_bio->bi_iter.bi_size,
+						  fs_info->sectorsize);
+			sums += csum_size * nr_sectors;
 
 			ret = btrfs_map_bio(fs_info, comp_bio, mirror_num, 0);
 			if (ret) {
@@ -643,7 +673,8 @@ blk_status_t btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
 				bio_endio(comp_bio);
 			}
 
-			comp_bio = btrfs_bio_alloc(bdev, cur_disk_byte);
+			comp_bio = btrfs_bio_alloc(cur_disk_byte);
+			bio_set_dev(comp_bio, bdev);
 			comp_bio->bi_opf = REQ_OP_READ;
 			comp_bio->bi_private = cb;
 			comp_bio->bi_end_io = end_compressed_bio_read;
diff --git a/fs/btrfs/compression.h b/fs/btrfs/compression.h
index 9976fe0f7526..2035b8eb1290 100644
--- a/fs/btrfs/compression.h
+++ b/fs/btrfs/compression.h
@@ -61,7 +61,7 @@ struct compressed_bio {
 	 * the start of a variable length array of checksums only
 	 * used by reads
 	 */
-	u32 sums;
+	u8 sums[];
 };
 
 static inline unsigned int btrfs_compress_type(unsigned int type_level)
@@ -173,6 +173,7 @@ extern const struct btrfs_compress_op btrfs_lzo_compress;
 extern const struct btrfs_compress_op btrfs_zstd_compress;
 
 const char* btrfs_compress_type2str(enum btrfs_compression_type type);
+bool btrfs_compress_is_valid_type(const char *str, size_t len);
 
 int btrfs_compress_heuristic(struct inode *inode, u64 start, u64 end);
 
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 0a61dff27f57..299e11e6c554 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -19,6 +19,7 @@
 #include <linux/kobject.h>
 #include <trace/events/btrfs.h>
 #include <asm/kmap_types.h>
+#include <asm/unaligned.h>
 #include <linux/pagemap.h>
 #include <linux/btrfs.h>
 #include <linux/btrfs_tree.h>
@@ -31,11 +32,13 @@
 #include "extent_io.h"
 #include "extent_map.h"
 #include "async-thread.h"
+#include "block-rsv.h"
 
 struct btrfs_trans_handle;
 struct btrfs_transaction;
 struct btrfs_pending_snapshot;
 struct btrfs_delayed_ref_root;
+struct btrfs_space_info;
 extern struct kmem_cache *btrfs_trans_handle_cachep;
 extern struct kmem_cache *btrfs_bit_radix_cachep;
 extern struct kmem_cache *btrfs_path_cachep;
@@ -45,7 +48,16 @@ struct btrfs_ref;
 
 #define BTRFS_MAGIC 0x4D5F53665248425FULL /* ascii _BHRfS_M, no null */
 
-#define BTRFS_MAX_MIRRORS 3
+/*
+ * Maximum number of mirrors that can be available for all profiles counting
+ * the target device of dev-replace as one. During an active device replace
+ * procedure, the target device of the copy operation is a mirror for the
+ * filesystem data as well that can be used to read data in order to repair
+ * read errors on other disks.
+ *
+ * Current value is derived from RAID1 with 2 copies.
+ */
+#define BTRFS_MAX_MIRRORS (2 + 1)
 
 #define BTRFS_MAX_LEVEL 8
 
@@ -72,6 +84,7 @@ struct btrfs_ref;
 
 /* four bytes for CRC32 */
 static const int btrfs_csum_sizes[] = { 4 };
+static const char *btrfs_csum_names[] = { "crc32c" };
 
 #define BTRFS_EMPTY_DIR_SIZE 0
 
@@ -99,10 +112,6 @@ static inline u32 count_max_extents(u64 size)
 	return div_u64(size + BTRFS_MAX_EXTENT_SIZE - 1, BTRFS_MAX_EXTENT_SIZE);
 }
 
-struct btrfs_mapping_tree {
-	struct extent_map_tree map_tree;
-};
-
 static inline unsigned long btrfs_chunk_item_size(int num_stripes)
 {
 	BUG_ON(num_stripes == 0);
@@ -395,115 +404,6 @@ struct raid_kobject {
 	struct list_head list;
 };
 
-struct btrfs_space_info {
-	spinlock_t lock;
-
-	u64 total_bytes;	/* total bytes in the space,
-				   this doesn't take mirrors into account */
-	u64 bytes_used;		/* total bytes used,
-				   this doesn't take mirrors into account */
-	u64 bytes_pinned;	/* total bytes pinned, will be freed when the
-				   transaction finishes */
-	u64 bytes_reserved;	/* total bytes the allocator has reserved for
-				   current allocations */
-	u64 bytes_may_use;	/* number of bytes that may be used for
-				   delalloc/allocations */
-	u64 bytes_readonly;	/* total bytes that are read only */
-
-	u64 max_extent_size;	/* This will hold the maximum extent size of
-				   the space info if we had an ENOSPC in the
-				   allocator. */
-
-	unsigned int full:1;	/* indicates that we cannot allocate any more
-				   chunks for this space */
-	unsigned int chunk_alloc:1;	/* set if we are allocating a chunk */
-
-	unsigned int flush:1;		/* set if we are trying to make space */
-
-	unsigned int force_alloc;	/* set if we need to force a chunk
-					   alloc for this space */
-
-	u64 disk_used;		/* total bytes used on disk */
-	u64 disk_total;		/* total bytes on disk, takes mirrors into
-				   account */
-
-	u64 flags;
-
-	/*
-	 * bytes_pinned is kept in line with what is actually pinned, as in
-	 * we've called update_block_group and dropped the bytes_used counter
-	 * and increased the bytes_pinned counter.  However this means that
-	 * bytes_pinned does not reflect the bytes that will be pinned once the
-	 * delayed refs are flushed, so this counter is inc'ed every time we
-	 * call btrfs_free_extent so it is a realtime count of what will be
-	 * freed once the transaction is committed.  It will be zeroed every
-	 * time the transaction commits.
-	 */
-	struct percpu_counter total_bytes_pinned;
-
-	struct list_head list;
-	/* Protected by the spinlock 'lock'. */
-	struct list_head ro_bgs;
-	struct list_head priority_tickets;
-	struct list_head tickets;
-	/*
-	 * tickets_id just indicates the next ticket will be handled, so note
-	 * it's not stored per ticket.
-	 */
-	u64 tickets_id;
-
-	struct rw_semaphore groups_sem;
-	/* for block groups in our same type */
-	struct list_head block_groups[BTRFS_NR_RAID_TYPES];
-	wait_queue_head_t wait;
-
-	struct kobject kobj;
-	struct kobject *block_group_kobjs[BTRFS_NR_RAID_TYPES];
-};
-
-/*
- * Types of block reserves
- */
-enum {
-	BTRFS_BLOCK_RSV_GLOBAL,
-	BTRFS_BLOCK_RSV_DELALLOC,
-	BTRFS_BLOCK_RSV_TRANS,
-	BTRFS_BLOCK_RSV_CHUNK,
-	BTRFS_BLOCK_RSV_DELOPS,
-	BTRFS_BLOCK_RSV_DELREFS,
-	BTRFS_BLOCK_RSV_EMPTY,
-	BTRFS_BLOCK_RSV_TEMP,
-};
-
-struct btrfs_block_rsv {
-	u64 size;
-	u64 reserved;
-	struct btrfs_space_info *space_info;
-	spinlock_t lock;
-	unsigned short full;
-	unsigned short type;
-	unsigned short failfast;
-
-	/*
-	 * Qgroup equivalent for @size @reserved
-	 *
-	 * Unlike normal @size/@reserved for inode rsv, qgroup doesn't care
-	 * about things like csum size nor how many tree blocks it will need to
-	 * reserve.
-	 *
-	 * Qgroup cares more about net change of the extent usage.
-	 *
-	 * So for one newly inserted file extent, in worst case it will cause
-	 * leaf split and level increase, nodesize for each file extent is
-	 * already too much.
-	 *
-	 * In short, qgroup_size/reserved is the upper limit of possible needed
-	 * qgroup metadata reservation.
-	 */
-	u64 qgroup_rsv_size;
-	u64 qgroup_rsv_reserved;
-};
-
 /*
  * free clusters are used to claim free space in relatively large chunks,
  * allowing us to do less seeky writes. They are used for all metadata
@@ -786,11 +686,18 @@ enum {
 	/*
 	 * Indicate that balance has been set up from the ioctl and is in the
 	 * main phase. The fs_info::balance_ctl is initialized.
+	 * Set and cleared while holding fs_info::balance_mutex.
 	 */
 	BTRFS_FS_BALANCE_RUNNING,
 
 	/* Indicate that the cleaner thread is awake and doing something. */
 	BTRFS_FS_CLEANER_RUNNING,
+
+	/*
+	 * The checksumming has an optimized version and is considered fast,
+	 * so we don't need to offload checksums to workqueues.
+	 */
+	BTRFS_FS_CSUM_IMPL_FAST,
 };
 
 struct btrfs_fs_info {
@@ -824,7 +731,7 @@ struct btrfs_fs_info {
 	struct extent_io_tree *pinned_extents;
 
 	/* logical->physical extent mapping */
-	struct btrfs_mapping_tree mapping_tree;
+	struct extent_map_tree mapping_tree;
 
 	/*
 	 * block reservation for extent, checksum, root tree and
@@ -1160,6 +1067,14 @@ struct btrfs_fs_info {
 	spinlock_t swapfile_pins_lock;
 	struct rb_root swapfile_pins;
 
+	struct crypto_shash *csum_shash;
+
+	/*
+	 * Number of send operations in progress.
+	 * Updated while holding fs_info::balance_mutex.
+	 */
+	int send_in_progress;
+
 #ifdef CONFIG_BTRFS_FS_REF_VERIFY
 	spinlock_t ref_verify_lock;
 	struct rb_root block_tree;
@@ -2451,6 +2366,11 @@ static inline int btrfs_super_csum_size(const struct btrfs_super_block *s)
 	return btrfs_csum_sizes[t];
 }
 
+static inline const char *btrfs_super_csum_name(u16 csum_type)
+{
+	/* csum type is validated at mount time */
+	return btrfs_csum_names[csum_type];
+}
 
 /*
  * The leaf data grows from end-to-front in the node.
@@ -2642,6 +2562,16 @@ BTRFS_SETGET_STACK_FUNCS(stack_dev_replace_cursor_right,
 	((unsigned long)(BTRFS_LEAF_DATA_OFFSET + \
 	btrfs_item_offset_nr(leaf, slot)))
 
+static inline u32 btrfs_crc32c(u32 crc, const void *address, unsigned length)
+{
+	return crc32c(crc, address, length);
+}
+
+static inline void btrfs_crc32c_final(u32 crc, u8 *result)
+{
+	put_unaligned_le32(~crc, result);
+}
+
 static inline u64 btrfs_name_hash(const char *name, int len)
 {
        return crc32c((u32)~1, name, len);
@@ -2656,12 +2586,6 @@ static inline u64 btrfs_extref_hash(u64 parent_objectid, const char *name,
        return (u64) crc32c(parent_objectid, name, len);
 }
 
-static inline bool btrfs_mixed_space_info(struct btrfs_space_info *space_info)
-{
-	return ((space_info->flags & BTRFS_BLOCK_GROUP_METADATA) &&
-		(space_info->flags & BTRFS_BLOCK_GROUP_DATA));
-}
-
 static inline gfp_t btrfs_alloc_write_mask(struct address_space *mapping)
 {
 	return mapping_gfp_constraint(mapping, ~__GFP_FS);
@@ -2698,8 +2622,6 @@ static inline u64 btrfs_calc_trunc_metadata_size(struct btrfs_fs_info *fs_info,
 	return (u64)fs_info->nodesize * BTRFS_MAX_LEVEL * num_items;
 }
 
-int btrfs_should_throttle_delayed_refs(struct btrfs_trans_handle *trans);
-bool btrfs_check_space_for_delayed_refs(struct btrfs_fs_info *fs_info);
 void btrfs_dec_block_group_reservations(struct btrfs_fs_info *fs_info,
 					 const u64 start);
 void btrfs_wait_block_group_reservations(struct btrfs_block_group_cache *bg);
@@ -2814,17 +2736,28 @@ enum btrfs_flush_state {
 	COMMIT_TRANS		=	9,
 };
 
-int btrfs_alloc_data_chunk_ondemand(struct btrfs_inode *inode, u64 bytes);
-int btrfs_check_data_free_space(struct inode *inode,
-			struct extent_changeset **reserved, u64 start, u64 len);
-void btrfs_free_reserved_data_space(struct inode *inode,
-			struct extent_changeset *reserved, u64 start, u64 len);
-void btrfs_delalloc_release_space(struct inode *inode,
-				  struct extent_changeset *reserved,
-				  u64 start, u64 len, bool qgroup_free);
-void btrfs_free_reserved_data_space_noquota(struct inode *inode, u64 start,
-					    u64 len);
-void btrfs_trans_release_chunk_metadata(struct btrfs_trans_handle *trans);
+/*
+ * control flags for do_chunk_alloc's force field
+ * CHUNK_ALLOC_NO_FORCE means to only allocate a chunk
+ * if we really need one.
+ *
+ * CHUNK_ALLOC_LIMITED means to only try and allocate one
+ * if we have very few chunks already allocated.  This is
+ * used as part of the clustering code to help make sure
+ * we have a good pool of storage to cluster in, without
+ * filling the FS with empty chunks
+ *
+ * CHUNK_ALLOC_FORCE means it must try to allocate one
+ *
+ */
+enum btrfs_chunk_alloc_enum {
+	CHUNK_ALLOC_NO_FORCE,
+	CHUNK_ALLOC_LIMITED,
+	CHUNK_ALLOC_FORCE,
+};
+
+int btrfs_chunk_alloc(struct btrfs_trans_handle *trans, u64 flags,
+		      enum btrfs_chunk_alloc_enum force);
 int btrfs_subvolume_reserve_metadata(struct btrfs_root *root,
 				     struct btrfs_block_rsv *rsv,
 				     int nitems, bool use_global_rsv);
@@ -2834,41 +2767,6 @@ void btrfs_delalloc_release_extents(struct btrfs_inode *inode, u64 num_bytes,
 				    bool qgroup_free);
 
 int btrfs_delalloc_reserve_metadata(struct btrfs_inode *inode, u64 num_bytes);
-void btrfs_delalloc_release_metadata(struct btrfs_inode *inode, u64 num_bytes,
-				     bool qgroup_free);
-int btrfs_delalloc_reserve_space(struct inode *inode,
-			struct extent_changeset **reserved, u64 start, u64 len);
-void btrfs_init_block_rsv(struct btrfs_block_rsv *rsv, unsigned short type);
-struct btrfs_block_rsv *btrfs_alloc_block_rsv(struct btrfs_fs_info *fs_info,
-					      unsigned short type);
-void btrfs_init_metadata_block_rsv(struct btrfs_fs_info *fs_info,
-				   struct btrfs_block_rsv *rsv,
-				   unsigned short type);
-void btrfs_free_block_rsv(struct btrfs_fs_info *fs_info,
-			  struct btrfs_block_rsv *rsv);
-int btrfs_block_rsv_add(struct btrfs_root *root,
-			struct btrfs_block_rsv *block_rsv, u64 num_bytes,
-			enum btrfs_reserve_flush_enum flush);
-int btrfs_block_rsv_check(struct btrfs_block_rsv *block_rsv, int min_factor);
-int btrfs_block_rsv_refill(struct btrfs_root *root,
-			   struct btrfs_block_rsv *block_rsv, u64 min_reserved,
-			   enum btrfs_reserve_flush_enum flush);
-int btrfs_block_rsv_migrate(struct btrfs_block_rsv *src_rsv,
-			    struct btrfs_block_rsv *dst_rsv, u64 num_bytes,
-			    bool update_size);
-int btrfs_cond_migrate_bytes(struct btrfs_fs_info *fs_info,
-			     struct btrfs_block_rsv *dest, u64 num_bytes,
-			     int min_factor);
-void btrfs_block_rsv_release(struct btrfs_fs_info *fs_info,
-			     struct btrfs_block_rsv *block_rsv,
-			     u64 num_bytes);
-void btrfs_delayed_refs_rsv_release(struct btrfs_fs_info *fs_info, int nr);
-void btrfs_update_delayed_refs_rsv(struct btrfs_trans_handle *trans);
-int btrfs_delayed_refs_rsv_refill(struct btrfs_fs_info *fs_info,
-				  enum btrfs_reserve_flush_enum flush);
-void btrfs_migrate_to_delayed_refs_rsv(struct btrfs_fs_info *fs_info,
-				       struct btrfs_block_rsv *src,
-				       u64 num_bytes);
 int btrfs_inc_block_group_ro(struct btrfs_block_group_cache *cache);
 void btrfs_dec_block_group_ro(struct btrfs_block_group_cache *cache);
 void btrfs_put_block_group_cache(struct btrfs_fs_info *info);
@@ -3186,7 +3084,8 @@ int btrfs_find_name_in_ext_backref(struct extent_buffer *leaf, int slot,
 struct btrfs_dio_private;
 int btrfs_del_csums(struct btrfs_trans_handle *trans,
 		    struct btrfs_fs_info *fs_info, u64 bytenr, u64 len);
-blk_status_t btrfs_lookup_bio_sums(struct inode *inode, struct bio *bio, u32 *dst);
+blk_status_t btrfs_lookup_bio_sums(struct inode *inode, struct bio *bio,
+				   u8 *dst);
 blk_status_t btrfs_lookup_bio_sums_dio(struct inode *inode, struct bio *bio,
 			      u64 logical_offset);
 int btrfs_insert_file_extent(struct btrfs_trans_handle *trans,
@@ -3514,8 +3413,7 @@ __cold
 static inline void assfail(const char *expr, const char *file, int line)
 {
 	if (IS_ENABLED(CONFIG_BTRFS_ASSERT)) {
-		pr_err("assertion failed: %s, file: %s, line: %d\n",
-		       expr, file, line);
+		pr_err("assertion failed: %s, in %s:%d\n", expr, file, line);
 		BUG();
 	}
 }
@@ -3599,10 +3497,11 @@ do {									\
 /* compatibility and incompatibility defines */
 
 #define btrfs_set_fs_incompat(__fs_info, opt) \
-	__btrfs_set_fs_incompat((__fs_info), BTRFS_FEATURE_INCOMPAT_##opt)
+	__btrfs_set_fs_incompat((__fs_info), BTRFS_FEATURE_INCOMPAT_##opt, \
+				#opt)
 
 static inline void __btrfs_set_fs_incompat(struct btrfs_fs_info *fs_info,
-					   u64 flag)
+					   u64 flag, const char* name)
 {
 	struct btrfs_super_block *disk_super;
 	u64 features;
@@ -3615,18 +3514,20 @@ static inline void __btrfs_set_fs_incompat(struct btrfs_fs_info *fs_info,
 		if (!(features & flag)) {
 			features |= flag;
 			btrfs_set_super_incompat_flags(disk_super, features);
-			btrfs_info(fs_info, "setting %llu feature flag",
-					 flag);
+			btrfs_info(fs_info,
+				"setting incompat feature flag for %s (0x%llx)",
+				name, flag);
 		}
 		spin_unlock(&fs_info->super_lock);
 	}
 }
 
 #define btrfs_clear_fs_incompat(__fs_info, opt) \
-	__btrfs_clear_fs_incompat((__fs_info), BTRFS_FEATURE_INCOMPAT_##opt)
+	__btrfs_clear_fs_incompat((__fs_info), BTRFS_FEATURE_INCOMPAT_##opt, \
+				  #opt)
 
 static inline void __btrfs_clear_fs_incompat(struct btrfs_fs_info *fs_info,
-					     u64 flag)
+					     u64 flag, const char* name)
 {
 	struct btrfs_super_block *disk_super;
 	u64 features;
@@ -3639,8 +3540,9 @@ static inline void __btrfs_clear_fs_incompat(struct btrfs_fs_info *fs_info,
 		if (features & flag) {
 			features &= ~flag;
 			btrfs_set_super_incompat_flags(disk_super, features);
-			btrfs_info(fs_info, "clearing %llu feature flag",
-					 flag);
+			btrfs_info(fs_info,
+				"clearing incompat feature flag for %s (0x%llx)",
+				name, flag);
 		}
 		spin_unlock(&fs_info->super_lock);
 	}
@@ -3657,10 +3559,11 @@ static inline bool __btrfs_fs_incompat(struct btrfs_fs_info *fs_info, u64 flag)
 }
 
 #define btrfs_set_fs_compat_ro(__fs_info, opt) \
-	__btrfs_set_fs_compat_ro((__fs_info), BTRFS_FEATURE_COMPAT_RO_##opt)
+	__btrfs_set_fs_compat_ro((__fs_info), BTRFS_FEATURE_COMPAT_RO_##opt, \
+				 #opt)
 
 static inline void __btrfs_set_fs_compat_ro(struct btrfs_fs_info *fs_info,
-					    u64 flag)
+					    u64 flag, const char *name)
 {
 	struct btrfs_super_block *disk_super;
 	u64 features;
@@ -3673,18 +3576,20 @@ static inline void __btrfs_set_fs_compat_ro(struct btrfs_fs_info *fs_info,
 		if (!(features & flag)) {
 			features |= flag;
 			btrfs_set_super_compat_ro_flags(disk_super, features);
-			btrfs_info(fs_info, "setting %llu ro feature flag",
-				   flag);
+			btrfs_info(fs_info,
+				"setting compat-ro feature flag for %s (0x%llx)",
+				name, flag);
 		}
 		spin_unlock(&fs_info->super_lock);
 	}
 }
 
 #define btrfs_clear_fs_compat_ro(__fs_info, opt) \
-	__btrfs_clear_fs_compat_ro((__fs_info), BTRFS_FEATURE_COMPAT_RO_##opt)
+	__btrfs_clear_fs_compat_ro((__fs_info), BTRFS_FEATURE_COMPAT_RO_##opt, \
+				   #opt)
 
 static inline void __btrfs_clear_fs_compat_ro(struct btrfs_fs_info *fs_info,
-					      u64 flag)
+					      u64 flag, const char *name)
 {
 	struct btrfs_super_block *disk_super;
 	u64 features;
@@ -3697,8 +3602,9 @@ static inline void __btrfs_clear_fs_compat_ro(struct btrfs_fs_info *fs_info,
 		if (features & flag) {
 			features &= ~flag;
 			btrfs_set_super_compat_ro_flags(disk_super, features);
-			btrfs_info(fs_info, "clearing %llu ro feature flag",
-				   flag);
+			btrfs_info(fs_info,
+				"clearing compat-ro feature flag for %s (0x%llx)",
+				name, flag);
 		}
 		spin_unlock(&fs_info->super_lock);
 	}
diff --git a/fs/btrfs/delalloc-space.c b/fs/btrfs/delalloc-space.c
new file mode 100644
index 000000000000..17f7c0d38768
--- /dev/null
+++ b/fs/btrfs/delalloc-space.c
@@ -0,0 +1,494 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include "ctree.h"
+#include "delalloc-space.h"
+#include "block-rsv.h"
+#include "btrfs_inode.h"
+#include "space-info.h"
+#include "transaction.h"
+#include "qgroup.h"
+
+int btrfs_alloc_data_chunk_ondemand(struct btrfs_inode *inode, u64 bytes)
+{
+	struct btrfs_root *root = inode->root;
+	struct btrfs_fs_info *fs_info = root->fs_info;
+	struct btrfs_space_info *data_sinfo = fs_info->data_sinfo;
+	u64 used;
+	int ret = 0;
+	int need_commit = 2;
+	int have_pinned_space;
+
+	/* Make sure bytes are sectorsize aligned */
+	bytes = ALIGN(bytes, fs_info->sectorsize);
+
+	if (btrfs_is_free_space_inode(inode)) {
+		need_commit = 0;
+		ASSERT(current->journal_info);
+	}
+
+again:
+	/* Make sure we have enough space to handle the data first */
+	spin_lock(&data_sinfo->lock);
+	used = btrfs_space_info_used(data_sinfo, true);
+
+	if (used + bytes > data_sinfo->total_bytes) {
+		struct btrfs_trans_handle *trans;
+
+		/*
+		 * If we don't have enough free bytes in this space then we need
+		 * to alloc a new chunk.
+		 */
+		if (!data_sinfo->full) {
+			u64 alloc_target;
+
+			data_sinfo->force_alloc = CHUNK_ALLOC_FORCE;
+			spin_unlock(&data_sinfo->lock);
+
+			alloc_target = btrfs_data_alloc_profile(fs_info);
+			/*
+			 * It is ugly that we don't call nolock join
+			 * transaction for the free space inode case here.
+			 * But it is safe because we only do the data space
+			 * reservation for the free space cache in the
+			 * transaction context, the common join transaction
+			 * just increase the counter of the current transaction
+			 * handler, doesn't try to acquire the trans_lock of
+			 * the fs.
+			 */
+			trans = btrfs_join_transaction(root);
+			if (IS_ERR(trans))
+				return PTR_ERR(trans);
+
+			ret = btrfs_chunk_alloc(trans, alloc_target,
+						CHUNK_ALLOC_NO_FORCE);
+			btrfs_end_transaction(trans);
+			if (ret < 0) {
+				if (ret != -ENOSPC)
+					return ret;
+				else {
+					have_pinned_space = 1;
+					goto commit_trans;
+				}
+			}
+
+			goto again;
+		}
+
+		/*
+		 * If we don't have enough pinned space to deal with this
+		 * allocation, and no removed chunk in current transaction,
+		 * don't bother committing the transaction.
+		 */
+		have_pinned_space = __percpu_counter_compare(
+			&data_sinfo->total_bytes_pinned,
+			used + bytes - data_sinfo->total_bytes,
+			BTRFS_TOTAL_BYTES_PINNED_BATCH);
+		spin_unlock(&data_sinfo->lock);
+
+		/* Commit the current transaction and try again */
+commit_trans:
+		if (need_commit) {
+			need_commit--;
+
+			if (need_commit > 0) {
+				btrfs_start_delalloc_roots(fs_info, -1);
+				btrfs_wait_ordered_roots(fs_info, U64_MAX, 0,
+							 (u64)-1);
+			}
+
+			trans = btrfs_join_transaction(root);
+			if (IS_ERR(trans))
+				return PTR_ERR(trans);
+			if (have_pinned_space >= 0 ||
+			    test_bit(BTRFS_TRANS_HAVE_FREE_BGS,
+				     &trans->transaction->flags) ||
+			    need_commit > 0) {
+				ret = btrfs_commit_transaction(trans);
+				if (ret)
+					return ret;
+				/*
+				 * The cleaner kthread might still be doing iput
+				 * operations. Wait for it to finish so that
+				 * more space is released.  We don't need to
+				 * explicitly run the delayed iputs here because
+				 * the commit_transaction would have woken up
+				 * the cleaner.
+				 */
+				ret = btrfs_wait_on_delayed_iputs(fs_info);
+				if (ret)
+					return ret;
+				goto again;
+			} else {
+				btrfs_end_transaction(trans);
+			}
+		}
+
+		trace_btrfs_space_reservation(fs_info,
+					      "space_info:enospc",
+					      data_sinfo->flags, bytes, 1);
+		return -ENOSPC;
+	}
+	btrfs_space_info_update_bytes_may_use(fs_info, data_sinfo, bytes);
+	trace_btrfs_space_reservation(fs_info, "space_info",
+				      data_sinfo->flags, bytes, 1);
+	spin_unlock(&data_sinfo->lock);
+
+	return 0;
+}
+
+int btrfs_check_data_free_space(struct inode *inode,
+			struct extent_changeset **reserved, u64 start, u64 len)
+{
+	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
+	int ret;
+
+	/* align the range */
+	len = round_up(start + len, fs_info->sectorsize) -
+	      round_down(start, fs_info->sectorsize);
+	start = round_down(start, fs_info->sectorsize);
+
+	ret = btrfs_alloc_data_chunk_ondemand(BTRFS_I(inode), len);
+	if (ret < 0)
+		return ret;
+
+	/* Use new btrfs_qgroup_reserve_data to reserve precious data space. */
+	ret = btrfs_qgroup_reserve_data(inode, reserved, start, len);
+	if (ret < 0)
+		btrfs_free_reserved_data_space_noquota(inode, start, len);
+	else
+		ret = 0;
+	return ret;
+}
+
+/*
+ * Called if we need to clear a data reservation for this inode
+ * Normally in a error case.
+ *
+ * This one will *NOT* use accurate qgroup reserved space API, just for case
+ * which we can't sleep and is sure it won't affect qgroup reserved space.
+ * Like clear_bit_hook().
+ */
+void btrfs_free_reserved_data_space_noquota(struct inode *inode, u64 start,
+					    u64 len)
+{
+	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
+	struct btrfs_space_info *data_sinfo;
+
+	/* Make sure the range is aligned to sectorsize */
+	len = round_up(start + len, fs_info->sectorsize) -
+	      round_down(start, fs_info->sectorsize);
+	start = round_down(start, fs_info->sectorsize);
+
+	data_sinfo = fs_info->data_sinfo;
+	spin_lock(&data_sinfo->lock);
+	btrfs_space_info_update_bytes_may_use(fs_info, data_sinfo, -len);
+	trace_btrfs_space_reservation(fs_info, "space_info",
+				      data_sinfo->flags, len, 0);
+	spin_unlock(&data_sinfo->lock);
+}
+
+/*
+ * Called if we need to clear a data reservation for this inode
+ * Normally in a error case.
+ *
+ * This one will handle the per-inode data rsv map for accurate reserved
+ * space framework.
+ */
+void btrfs_free_reserved_data_space(struct inode *inode,
+			struct extent_changeset *reserved, u64 start, u64 len)
+{
+	struct btrfs_root *root = BTRFS_I(inode)->root;
+
+	/* Make sure the range is aligned to sectorsize */
+	len = round_up(start + len, root->fs_info->sectorsize) -
+	      round_down(start, root->fs_info->sectorsize);
+	start = round_down(start, root->fs_info->sectorsize);
+
+	btrfs_free_reserved_data_space_noquota(inode, start, len);
+	btrfs_qgroup_free_data(inode, reserved, start, len);
+}
+
+/**
+ * btrfs_inode_rsv_release - release any excessive reservation.
+ * @inode - the inode we need to release from.
+ * @qgroup_free - free or convert qgroup meta.
+ *   Unlike normal operation, qgroup meta reservation needs to know if we are
+ *   freeing qgroup reservation or just converting it into per-trans.  Normally
+ *   @qgroup_free is true for error handling, and false for normal release.
+ *
+ * This is the same as btrfs_block_rsv_release, except that it handles the
+ * tracepoint for the reservation.
+ */
+static void btrfs_inode_rsv_release(struct btrfs_inode *inode, bool qgroup_free)
+{
+	struct btrfs_fs_info *fs_info = inode->root->fs_info;
+	struct btrfs_block_rsv *block_rsv = &inode->block_rsv;
+	u64 released = 0;
+	u64 qgroup_to_release = 0;
+
+	/*
+	 * Since we statically set the block_rsv->size we just want to say we
+	 * are releasing 0 bytes, and then we'll just get the reservation over
+	 * the size free'd.
+	 */
+	released = __btrfs_block_rsv_release(fs_info, block_rsv, 0,
+					     &qgroup_to_release);
+	if (released > 0)
+		trace_btrfs_space_reservation(fs_info, "delalloc",
+					      btrfs_ino(inode), released, 0);
+	if (qgroup_free)
+		btrfs_qgroup_free_meta_prealloc(inode->root, qgroup_to_release);
+	else
+		btrfs_qgroup_convert_reserved_meta(inode->root,
+						   qgroup_to_release);
+}
+
+static void btrfs_calculate_inode_block_rsv_size(struct btrfs_fs_info *fs_info,
+						 struct btrfs_inode *inode)
+{
+	struct btrfs_block_rsv *block_rsv = &inode->block_rsv;
+	u64 reserve_size = 0;
+	u64 qgroup_rsv_size = 0;
+	u64 csum_leaves;
+	unsigned outstanding_extents;
+
+	lockdep_assert_held(&inode->lock);
+	outstanding_extents = inode->outstanding_extents;
+	if (outstanding_extents)
+		reserve_size = btrfs_calc_trans_metadata_size(fs_info,
+						outstanding_extents + 1);
+	csum_leaves = btrfs_csum_bytes_to_leaves(fs_info,
+						 inode->csum_bytes);
+	reserve_size += btrfs_calc_trans_metadata_size(fs_info,
+						       csum_leaves);
+	/*
+	 * For qgroup rsv, the calculation is very simple:
+	 * account one nodesize for each outstanding extent
+	 *
+	 * This is overestimating in most cases.
+	 */
+	qgroup_rsv_size = (u64)outstanding_extents * fs_info->nodesize;
+
+	spin_lock(&block_rsv->lock);
+	block_rsv->size = reserve_size;
+	block_rsv->qgroup_rsv_size = qgroup_rsv_size;
+	spin_unlock(&block_rsv->lock);
+}
+
+static void calc_inode_reservations(struct btrfs_fs_info *fs_info,
+				    u64 num_bytes, u64 *meta_reserve,
+				    u64 *qgroup_reserve)
+{
+	u64 nr_extents = count_max_extents(num_bytes);
+	u64 csum_leaves = btrfs_csum_bytes_to_leaves(fs_info, num_bytes);
+
+	/* We add one for the inode update at finish ordered time */
+	*meta_reserve = btrfs_calc_trans_metadata_size(fs_info,
+						nr_extents + csum_leaves + 1);
+	*qgroup_reserve = nr_extents * fs_info->nodesize;
+}
+
+int btrfs_delalloc_reserve_metadata(struct btrfs_inode *inode, u64 num_bytes)
+{
+	struct btrfs_root *root = inode->root;
+	struct btrfs_fs_info *fs_info = root->fs_info;
+	struct btrfs_block_rsv *block_rsv = &inode->block_rsv;
+	u64 meta_reserve, qgroup_reserve;
+	unsigned nr_extents;
+	enum btrfs_reserve_flush_enum flush = BTRFS_RESERVE_FLUSH_ALL;
+	int ret = 0;
+	bool delalloc_lock = true;
+
+	/*
+	 * If we are a free space inode we need to not flush since we will be in
+	 * the middle of a transaction commit.  We also don't need the delalloc
+	 * mutex since we won't race with anybody.  We need this mostly to make
+	 * lockdep shut its filthy mouth.
+	 *
+	 * If we have a transaction open (can happen if we call truncate_block
+	 * from truncate), then we need FLUSH_LIMIT so we don't deadlock.
+	 */
+	if (btrfs_is_free_space_inode(inode)) {
+		flush = BTRFS_RESERVE_NO_FLUSH;
+		delalloc_lock = false;
+	} else {
+		if (current->journal_info)
+			flush = BTRFS_RESERVE_FLUSH_LIMIT;
+
+		if (btrfs_transaction_in_commit(fs_info))
+			schedule_timeout(1);
+	}
+
+	if (delalloc_lock)
+		mutex_lock(&inode->delalloc_mutex);
+
+	num_bytes = ALIGN(num_bytes, fs_info->sectorsize);
+
+	/*
+	 * We always want to do it this way, every other way is wrong and ends
+	 * in tears.  Pre-reserving the amount we are going to add will always
+	 * be the right way, because otherwise if we have enough parallelism we
+	 * could end up with thousands of inodes all holding little bits of
+	 * reservations they were able to make previously and the only way to
+	 * reclaim that space is to ENOSPC out the operations and clear
+	 * everything out and try again, which is bad.  This way we just
+	 * over-reserve slightly, and clean up the mess when we are done.
+	 */
+	calc_inode_reservations(fs_info, num_bytes, &meta_reserve,
+				&qgroup_reserve);
+	ret = btrfs_qgroup_reserve_meta_prealloc(root, qgroup_reserve, true);
+	if (ret)
+		goto out_fail;
+	ret = btrfs_reserve_metadata_bytes(root, block_rsv, meta_reserve, flush);
+	if (ret)
+		goto out_qgroup;
+
+	/*
+	 * Now we need to update our outstanding extents and csum bytes _first_
+	 * and then add the reservation to the block_rsv.  This keeps us from
+	 * racing with an ordered completion or some such that would think it
+	 * needs to free the reservation we just made.
+	 */
+	spin_lock(&inode->lock);
+	nr_extents = count_max_extents(num_bytes);
+	btrfs_mod_outstanding_extents(inode, nr_extents);
+	inode->csum_bytes += num_bytes;
+	btrfs_calculate_inode_block_rsv_size(fs_info, inode);
+	spin_unlock(&inode->lock);
+
+	/* Now we can safely add our space to our block rsv */
+	btrfs_block_rsv_add_bytes(block_rsv, meta_reserve, false);
+	trace_btrfs_space_reservation(root->fs_info, "delalloc",
+				      btrfs_ino(inode), meta_reserve, 1);
+
+	spin_lock(&block_rsv->lock);
+	block_rsv->qgroup_rsv_reserved += qgroup_reserve;
+	spin_unlock(&block_rsv->lock);
+
+	if (delalloc_lock)
+		mutex_unlock(&inode->delalloc_mutex);
+	return 0;
+out_qgroup:
+	btrfs_qgroup_free_meta_prealloc(root, qgroup_reserve);
+out_fail:
+	btrfs_inode_rsv_release(inode, true);
+	if (delalloc_lock)
+		mutex_unlock(&inode->delalloc_mutex);
+	return ret;
+}
+
+/**
+ * btrfs_delalloc_release_metadata - release a metadata reservation for an inode
+ * @inode: the inode to release the reservation for.
+ * @num_bytes: the number of bytes we are releasing.
+ * @qgroup_free: free qgroup reservation or convert it to per-trans reservation
+ *
+ * This will release the metadata reservation for an inode.  This can be called
+ * once we complete IO for a given set of bytes to release their metadata
+ * reservations, or on error for the same reason.
+ */
+void btrfs_delalloc_release_metadata(struct btrfs_inode *inode, u64 num_bytes,
+				     bool qgroup_free)
+{
+	struct btrfs_fs_info *fs_info = inode->root->fs_info;
+
+	num_bytes = ALIGN(num_bytes, fs_info->sectorsize);
+	spin_lock(&inode->lock);
+	inode->csum_bytes -= num_bytes;
+	btrfs_calculate_inode_block_rsv_size(fs_info, inode);
+	spin_unlock(&inode->lock);
+
+	if (btrfs_is_testing(fs_info))
+		return;
+
+	btrfs_inode_rsv_release(inode, qgroup_free);
+}
+
+/**
+ * btrfs_delalloc_release_extents - release our outstanding_extents
+ * @inode: the inode to balance the reservation for.
+ * @num_bytes: the number of bytes we originally reserved with
+ * @qgroup_free: do we need to free qgroup meta reservation or convert them.
+ *
+ * When we reserve space we increase outstanding_extents for the extents we may
+ * add.  Once we've set the range as delalloc or created our ordered extents we
+ * have outstanding_extents to track the real usage, so we use this to free our
+ * temporarily tracked outstanding_extents.  This _must_ be used in conjunction
+ * with btrfs_delalloc_reserve_metadata.
+ */
+void btrfs_delalloc_release_extents(struct btrfs_inode *inode, u64 num_bytes,
+				    bool qgroup_free)
+{
+	struct btrfs_fs_info *fs_info = inode->root->fs_info;
+	unsigned num_extents;
+
+	spin_lock(&inode->lock);
+	num_extents = count_max_extents(num_bytes);
+	btrfs_mod_outstanding_extents(inode, -num_extents);
+	btrfs_calculate_inode_block_rsv_size(fs_info, inode);
+	spin_unlock(&inode->lock);
+
+	if (btrfs_is_testing(fs_info))
+		return;
+
+	btrfs_inode_rsv_release(inode, qgroup_free);
+}
+
+/**
+ * btrfs_delalloc_reserve_space - reserve data and metadata space for
+ * delalloc
+ * @inode: inode we're writing to
+ * @start: start range we are writing to
+ * @len: how long the range we are writing to
+ * @reserved: mandatory parameter, record actually reserved qgroup ranges of
+ * 	      current reservation.
+ *
+ * This will do the following things
+ *
+ * - reserve space in data space info for num bytes
+ *   and reserve precious corresponding qgroup space
+ *   (Done in check_data_free_space)
+ *
+ * - reserve space for metadata space, based on the number of outstanding
+ *   extents and how much csums will be needed
+ *   also reserve metadata space in a per root over-reserve method.
+ * - add to the inodes->delalloc_bytes
+ * - add it to the fs_info's delalloc inodes list.
+ *   (Above 3 all done in delalloc_reserve_metadata)
+ *
+ * Return 0 for success
+ * Return <0 for error(-ENOSPC or -EQUOT)
+ */
+int btrfs_delalloc_reserve_space(struct inode *inode,
+			struct extent_changeset **reserved, u64 start, u64 len)
+{
+	int ret;
+
+	ret = btrfs_check_data_free_space(inode, reserved, start, len);
+	if (ret < 0)
+		return ret;
+	ret = btrfs_delalloc_reserve_metadata(BTRFS_I(inode), len);
+	if (ret < 0)
+		btrfs_free_reserved_data_space(inode, *reserved, start, len);
+	return ret;
+}
+
+/**
+ * btrfs_delalloc_release_space - release data and metadata space for delalloc
+ * @inode: inode we're releasing space for
+ * @start: start position of the space already reserved
+ * @len: the len of the space already reserved
+ * @release_bytes: the len of the space we consumed or didn't use
+ *
+ * This function will release the metadata space that was not used and will
+ * decrement ->delalloc_bytes and remove it from the fs_info delalloc_inodes
+ * list if there are no delalloc bytes left.
+ * Also it will handle the qgroup reserved space.
+ */
+void btrfs_delalloc_release_space(struct inode *inode,
+				  struct extent_changeset *reserved,
+				  u64 start, u64 len, bool qgroup_free)
+{
+	btrfs_delalloc_release_metadata(BTRFS_I(inode), len, qgroup_free);
+	btrfs_free_reserved_data_space(inode, reserved, start, len);
+}
diff --git a/fs/btrfs/delalloc-space.h b/fs/btrfs/delalloc-space.h
new file mode 100644
index 000000000000..54466fbd7075
--- /dev/null
+++ b/fs/btrfs/delalloc-space.h
@@ -0,0 +1,23 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef BTRFS_DELALLOC_SPACE_H
+#define BTRFS_DELALLOC_SPACE_H
+
+struct extent_changeset;
+
+int btrfs_alloc_data_chunk_ondemand(struct btrfs_inode *inode, u64 bytes);
+int btrfs_check_data_free_space(struct inode *inode,
+			struct extent_changeset **reserved, u64 start, u64 len);
+void btrfs_free_reserved_data_space(struct inode *inode,
+			struct extent_changeset *reserved, u64 start, u64 len);
+void btrfs_delalloc_release_space(struct inode *inode,
+				  struct extent_changeset *reserved,
+				  u64 start, u64 len, bool qgroup_free);
+void btrfs_free_reserved_data_space_noquota(struct inode *inode, u64 start,
+					    u64 len);
+void btrfs_delalloc_release_metadata(struct btrfs_inode *inode, u64 num_bytes,
+				     bool qgroup_free);
+int btrfs_delalloc_reserve_space(struct inode *inode,
+			struct extent_changeset **reserved, u64 start, u64 len);
+
+#endif /* BTRFS_DELALLOC_SPACE_H */
diff --git a/fs/btrfs/delayed-ref.c b/fs/btrfs/delayed-ref.c
index a73fc23e2961..9a91d1eb0af4 100644
--- a/fs/btrfs/delayed-ref.c
+++ b/fs/btrfs/delayed-ref.c
@@ -10,6 +10,7 @@
 #include "delayed-ref.h"
 #include "transaction.h"
 #include "qgroup.h"
+#include "space-info.h"
 
 struct kmem_cache *btrfs_delayed_ref_head_cachep;
 struct kmem_cache *btrfs_delayed_tree_ref_cachep;
@@ -24,6 +25,179 @@ struct kmem_cache *btrfs_delayed_extent_op_cachep;
  * of hammering updates on the extent allocation tree.
  */
 
+bool btrfs_check_space_for_delayed_refs(struct btrfs_fs_info *fs_info)
+{
+	struct btrfs_block_rsv *delayed_refs_rsv = &fs_info->delayed_refs_rsv;
+	struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
+	bool ret = false;
+	u64 reserved;
+
+	spin_lock(&global_rsv->lock);
+	reserved = global_rsv->reserved;
+	spin_unlock(&global_rsv->lock);
+
+	/*
+	 * Since the global reserve is just kind of magic we don't really want
+	 * to rely on it to save our bacon, so if our size is more than the
+	 * delayed_refs_rsv and the global rsv then it's time to think about
+	 * bailing.
+	 */
+	spin_lock(&delayed_refs_rsv->lock);
+	reserved += delayed_refs_rsv->reserved;
+	if (delayed_refs_rsv->size >= reserved)
+		ret = true;
+	spin_unlock(&delayed_refs_rsv->lock);
+	return ret;
+}
+
+int btrfs_should_throttle_delayed_refs(struct btrfs_trans_handle *trans)
+{
+	u64 num_entries =
+		atomic_read(&trans->transaction->delayed_refs.num_entries);
+	u64 avg_runtime;
+	u64 val;
+
+	smp_mb();
+	avg_runtime = trans->fs_info->avg_delayed_ref_runtime;
+	val = num_entries * avg_runtime;
+	if (val >= NSEC_PER_SEC)
+		return 1;
+	if (val >= NSEC_PER_SEC / 2)
+		return 2;
+
+	return btrfs_check_space_for_delayed_refs(trans->fs_info);
+}
+
+/**
+ * btrfs_delayed_refs_rsv_release - release a ref head's reservation.
+ * @fs_info - the fs_info for our fs.
+ * @nr - the number of items to drop.
+ *
+ * This drops the delayed ref head's count from the delayed refs rsv and frees
+ * any excess reservation we had.
+ */
+void btrfs_delayed_refs_rsv_release(struct btrfs_fs_info *fs_info, int nr)
+{
+	struct btrfs_block_rsv *block_rsv = &fs_info->delayed_refs_rsv;
+	u64 num_bytes = btrfs_calc_trans_metadata_size(fs_info, nr);
+	u64 released = 0;
+
+	released = __btrfs_block_rsv_release(fs_info, block_rsv, num_bytes,
+					     NULL);
+	if (released)
+		trace_btrfs_space_reservation(fs_info, "delayed_refs_rsv",
+					      0, released, 0);
+}
+
+/*
+ * btrfs_update_delayed_refs_rsv - adjust the size of the delayed refs rsv
+ * @trans - the trans that may have generated delayed refs
+ *
+ * This is to be called anytime we may have adjusted trans->delayed_ref_updates,
+ * it'll calculate the additional size and add it to the delayed_refs_rsv.
+ */
+void btrfs_update_delayed_refs_rsv(struct btrfs_trans_handle *trans)
+{
+	struct btrfs_fs_info *fs_info = trans->fs_info;
+	struct btrfs_block_rsv *delayed_rsv = &fs_info->delayed_refs_rsv;
+	u64 num_bytes;
+
+	if (!trans->delayed_ref_updates)
+		return;
+
+	num_bytes = btrfs_calc_trans_metadata_size(fs_info,
+						   trans->delayed_ref_updates);
+	spin_lock(&delayed_rsv->lock);
+	delayed_rsv->size += num_bytes;
+	delayed_rsv->full = 0;
+	spin_unlock(&delayed_rsv->lock);
+	trans->delayed_ref_updates = 0;
+}
+
+/**
+ * btrfs_migrate_to_delayed_refs_rsv - transfer bytes to our delayed refs rsv.
+ * @fs_info - the fs info for our fs.
+ * @src - the source block rsv to transfer from.
+ * @num_bytes - the number of bytes to transfer.
+ *
+ * This transfers up to the num_bytes amount from the src rsv to the
+ * delayed_refs_rsv.  Any extra bytes are returned to the space info.
+ */
+void btrfs_migrate_to_delayed_refs_rsv(struct btrfs_fs_info *fs_info,
+				       struct btrfs_block_rsv *src,
+				       u64 num_bytes)
+{
+	struct btrfs_block_rsv *delayed_refs_rsv = &fs_info->delayed_refs_rsv;
+	u64 to_free = 0;
+
+	spin_lock(&src->lock);
+	src->reserved -= num_bytes;
+	src->size -= num_bytes;
+	spin_unlock(&src->lock);
+
+	spin_lock(&delayed_refs_rsv->lock);
+	if (delayed_refs_rsv->size > delayed_refs_rsv->reserved) {
+		u64 delta = delayed_refs_rsv->size -
+			delayed_refs_rsv->reserved;
+		if (num_bytes > delta) {
+			to_free = num_bytes - delta;
+			num_bytes = delta;
+		}
+	} else {
+		to_free = num_bytes;
+		num_bytes = 0;
+	}
+
+	if (num_bytes)
+		delayed_refs_rsv->reserved += num_bytes;
+	if (delayed_refs_rsv->reserved >= delayed_refs_rsv->size)
+		delayed_refs_rsv->full = 1;
+	spin_unlock(&delayed_refs_rsv->lock);
+
+	if (num_bytes)
+		trace_btrfs_space_reservation(fs_info, "delayed_refs_rsv",
+					      0, num_bytes, 1);
+	if (to_free)
+		btrfs_space_info_add_old_bytes(fs_info,
+				delayed_refs_rsv->space_info, to_free);
+}
+
+/**
+ * btrfs_delayed_refs_rsv_refill - refill based on our delayed refs usage.
+ * @fs_info - the fs_info for our fs.
+ * @flush - control how we can flush for this reservation.
+ *
+ * This will refill the delayed block_rsv up to 1 items size worth of space and
+ * will return -ENOSPC if we can't make the reservation.
+ */
+int btrfs_delayed_refs_rsv_refill(struct btrfs_fs_info *fs_info,
+				  enum btrfs_reserve_flush_enum flush)
+{
+	struct btrfs_block_rsv *block_rsv = &fs_info->delayed_refs_rsv;
+	u64 limit = btrfs_calc_trans_metadata_size(fs_info, 1);
+	u64 num_bytes = 0;
+	int ret = -ENOSPC;
+
+	spin_lock(&block_rsv->lock);
+	if (block_rsv->reserved < block_rsv->size) {
+		num_bytes = block_rsv->size - block_rsv->reserved;
+		num_bytes = min(num_bytes, limit);
+	}
+	spin_unlock(&block_rsv->lock);
+
+	if (!num_bytes)
+		return 0;
+
+	ret = btrfs_reserve_metadata_bytes(fs_info->extent_root, block_rsv,
+					   num_bytes, flush);
+	if (ret)
+		return ret;
+	btrfs_block_rsv_add_bytes(block_rsv, num_bytes, 0);
+	trace_btrfs_space_reservation(fs_info, "delayed_refs_rsv",
+				      0, num_bytes, 1);
+	return 0;
+}
+
 /*
  * compare two delayed tree backrefs with same bytenr and type
  */
@@ -957,13 +1131,14 @@ int btrfs_add_delayed_extent_op(struct btrfs_trans_handle *trans,
 }
 
 /*
- * this does a simple search for the head node for a given extent.
- * It must be called with the delayed ref spinlock held, and it returns
- * the head node if any where found, or NULL if not.
+ * This does a simple search for the head node for a given extent.  Returns the
+ * head node if found, or NULL if not.
  */
 struct btrfs_delayed_ref_head *
 btrfs_find_delayed_ref_head(struct btrfs_delayed_ref_root *delayed_refs, u64 bytenr)
 {
+	lockdep_assert_held(&delayed_refs->lock);
+
 	return find_ref_head(delayed_refs, bytenr, false);
 }
 
diff --git a/fs/btrfs/delayed-ref.h b/fs/btrfs/delayed-ref.h
index c18f93ea88ed..1c977e6d45dc 100644
--- a/fs/btrfs/delayed-ref.h
+++ b/fs/btrfs/delayed-ref.h
@@ -364,6 +364,16 @@ struct btrfs_delayed_ref_head *btrfs_select_ref_head(
 
 int btrfs_check_delayed_seq(struct btrfs_fs_info *fs_info, u64 seq);
 
+void btrfs_delayed_refs_rsv_release(struct btrfs_fs_info *fs_info, int nr);
+void btrfs_update_delayed_refs_rsv(struct btrfs_trans_handle *trans);
+int btrfs_delayed_refs_rsv_refill(struct btrfs_fs_info *fs_info,
+				  enum btrfs_reserve_flush_enum flush);
+void btrfs_migrate_to_delayed_refs_rsv(struct btrfs_fs_info *fs_info,
+				       struct btrfs_block_rsv *src,
+				       u64 num_bytes);
+int btrfs_should_throttle_delayed_refs(struct btrfs_trans_handle *trans);
+bool btrfs_check_space_for_delayed_refs(struct btrfs_fs_info *fs_info);
+
 /*
  * helper functions to cast a node into its container
  */
diff --git a/fs/btrfs/dev-replace.c b/fs/btrfs/dev-replace.c
index ee0989c7e3a9..6b2e9aa83ffa 100644
--- a/fs/btrfs/dev-replace.c
+++ b/fs/btrfs/dev-replace.c
@@ -201,7 +201,7 @@ static int btrfs_init_dev_replace_tgtdev(struct btrfs_fs_info *fs_info,
 		return PTR_ERR(bdev);
 	}
 
-	filemap_write_and_wait(bdev->bd_inode->i_mapping);
+	sync_blockdev(bdev);
 
 	devices = &fs_info->fs_devices->devices;
 	list_for_each_entry(device, devices, dev_list) {
@@ -237,7 +237,6 @@ static int btrfs_init_dev_replace_tgtdev(struct btrfs_fs_info *fs_info,
 	}
 	rcu_assign_pointer(device->name, name);
 
-	mutex_lock(&fs_info->fs_devices->device_list_mutex);
 	set_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
 	device->generation = 0;
 	device->io_width = fs_info->sectorsize;
@@ -256,6 +255,8 @@ static int btrfs_init_dev_replace_tgtdev(struct btrfs_fs_info *fs_info,
 	device->dev_stats_valid = 1;
 	set_blocksize(device->bdev, BTRFS_BDEV_BLOCKSIZE);
 	device->fs_devices = fs_info->fs_devices;
+
+	mutex_lock(&fs_info->fs_devices->device_list_mutex);
 	list_add(&device->dev_list, &fs_info->fs_devices->devices);
 	fs_info->fs_devices->num_devices++;
 	fs_info->fs_devices->open_devices++;
@@ -399,7 +400,6 @@ static int btrfs_dev_replace_start(struct btrfs_fs_info *fs_info,
 	int ret;
 	struct btrfs_device *tgt_device = NULL;
 	struct btrfs_device *src_device = NULL;
-	bool need_unlock;
 
 	src_device = btrfs_find_device_by_devspec(fs_info, srcdevid,
 						  srcdev_name);
@@ -413,11 +413,6 @@ static int btrfs_dev_replace_start(struct btrfs_fs_info *fs_info,
 		return -ETXTBSY;
 	}
 
-	ret = btrfs_init_dev_replace_tgtdev(fs_info, tgtdev_name,
-					    src_device, &tgt_device);
-	if (ret)
-		return ret;
-
 	/*
 	 * Here we commit the transaction to make sure commit_total_bytes
 	 * of all the devices are updated.
@@ -431,7 +426,11 @@ static int btrfs_dev_replace_start(struct btrfs_fs_info *fs_info,
 		return PTR_ERR(trans);
 	}
 
-	need_unlock = true;
+	ret = btrfs_init_dev_replace_tgtdev(fs_info, tgtdev_name,
+					    src_device, &tgt_device);
+	if (ret)
+		return ret;
+
 	down_write(&dev_replace->rwsem);
 	switch (dev_replace->replace_state) {
 	case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED:
@@ -442,11 +441,11 @@ static int btrfs_dev_replace_start(struct btrfs_fs_info *fs_info,
 	case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED:
 		ASSERT(0);
 		ret = BTRFS_IOCTL_DEV_REPLACE_RESULT_ALREADY_STARTED;
+		up_write(&dev_replace->rwsem);
 		goto leave;
 	}
 
 	dev_replace->cont_reading_from_srcdev_mode = read_src;
-	WARN_ON(!src_device);
 	dev_replace->srcdev = src_device;
 	dev_replace->tgtdev = tgt_device;
 
@@ -471,7 +470,6 @@ static int btrfs_dev_replace_start(struct btrfs_fs_info *fs_info,
 	atomic64_set(&dev_replace->num_write_errors, 0);
 	atomic64_set(&dev_replace->num_uncorrectable_read_errors, 0);
 	up_write(&dev_replace->rwsem);
-	need_unlock = false;
 
 	ret = btrfs_sysfs_add_device_link(tgt_device->fs_devices, tgt_device);
 	if (ret)
@@ -479,16 +477,16 @@ static int btrfs_dev_replace_start(struct btrfs_fs_info *fs_info,
 
 	btrfs_wait_ordered_roots(fs_info, U64_MAX, 0, (u64)-1);
 
-	/* force writing the updated state information to disk */
-	trans = btrfs_start_transaction(root, 0);
+	/* Commit dev_replace state and reserve 1 item for it. */
+	trans = btrfs_start_transaction(root, 1);
 	if (IS_ERR(trans)) {
 		ret = PTR_ERR(trans);
-		need_unlock = true;
 		down_write(&dev_replace->rwsem);
 		dev_replace->replace_state =
 			BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED;
 		dev_replace->srcdev = NULL;
 		dev_replace->tgtdev = NULL;
+		up_write(&dev_replace->rwsem);
 		goto leave;
 	}
 
@@ -510,8 +508,6 @@ static int btrfs_dev_replace_start(struct btrfs_fs_info *fs_info,
 	return ret;
 
 leave:
-	if (need_unlock)
-		up_write(&dev_replace->rwsem);
 	btrfs_destroy_dev_replace_tgtdev(tgt_device);
 	return ret;
 }
@@ -678,7 +674,6 @@ static int btrfs_dev_replace_finishing(struct btrfs_fs_info *fs_info,
 	btrfs_device_set_disk_total_bytes(tgt_device,
 					  src_device->disk_total_bytes);
 	btrfs_device_set_bytes_used(tgt_device, src_device->bytes_used);
-	tgt_device->commit_total_bytes = src_device->commit_total_bytes;
 	tgt_device->commit_bytes_used = src_device->bytes_used;
 
 	btrfs_assign_next_active_device(src_device, tgt_device);
@@ -728,7 +723,7 @@ static void btrfs_dev_replace_update_device_in_mapping_tree(
 						struct btrfs_device *srcdev,
 						struct btrfs_device *tgtdev)
 {
-	struct extent_map_tree *em_tree = &fs_info->mapping_tree.map_tree;
+	struct extent_map_tree *em_tree = &fs_info->mapping_tree;
 	struct extent_map *em;
 	struct map_lookup *map;
 	u64 start = 0;
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index deb74a8c191a..41a2bd2e0c56 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -19,6 +19,7 @@
 #include <linux/crc32c.h>
 #include <linux/sched/mm.h>
 #include <asm/unaligned.h>
+#include <crypto/hash.h>
 #include "ctree.h"
 #include "disk-io.h"
 #include "transaction.h"
@@ -40,10 +41,6 @@
 #include "tree-checker.h"
 #include "ref-verify.h"
 
-#ifdef CONFIG_X86
-#include <asm/cpufeature.h>
-#endif
-
 #define BTRFS_SUPER_FLAG_SUPP	(BTRFS_HEADER_FLAG_WRITTEN |\
 				 BTRFS_HEADER_FLAG_RELOC |\
 				 BTRFS_SUPER_FLAG_ERROR |\
@@ -249,16 +246,6 @@ out:
 	return em;
 }
 
-u32 btrfs_csum_data(const char *data, u32 seed, size_t len)
-{
-	return crc32c(seed, data, len);
-}
-
-void btrfs_csum_final(u32 crc, u8 *result)
-{
-	put_unaligned_le32(~crc, result);
-}
-
 /*
  * Compute the csum of a btree block and store the result to provided buffer.
  *
@@ -266,6 +253,8 @@ void btrfs_csum_final(u32 crc, u8 *result)
  */
 static int csum_tree_block(struct extent_buffer *buf, u8 *result)
 {
+	struct btrfs_fs_info *fs_info = buf->fs_info;
+	SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
 	unsigned long len;
 	unsigned long cur_len;
 	unsigned long offset = BTRFS_CSUM_SIZE;
@@ -273,9 +262,12 @@ static int csum_tree_block(struct extent_buffer *buf, u8 *result)
 	unsigned long map_start;
 	unsigned long map_len;
 	int err;
-	u32 crc = ~(u32)0;
+
+	shash->tfm = fs_info->csum_shash;
+	crypto_shash_init(shash);
 
 	len = buf->len - offset;
+
 	while (len > 0) {
 		/*
 		 * Note: we don't need to check for the err == 1 case here, as
@@ -288,14 +280,13 @@ static int csum_tree_block(struct extent_buffer *buf, u8 *result)
 		if (WARN_ON(err))
 			return err;
 		cur_len = min(len, map_len - (offset - map_start));
-		crc = btrfs_csum_data(kaddr + offset - map_start,
-				      crc, cur_len);
+		crypto_shash_update(shash, kaddr + offset - map_start, cur_len);
 		len -= cur_len;
 		offset += cur_len;
 	}
 	memset(result, 0, BTRFS_CSUM_SIZE);
 
-	btrfs_csum_final(crc, result);
+	crypto_shash_final(shash, result);
 
 	return 0;
 }
@@ -356,6 +347,16 @@ out:
 	return ret;
 }
 
+static bool btrfs_supported_super_csum(u16 csum_type)
+{
+	switch (csum_type) {
+	case BTRFS_CSUM_TYPE_CRC32:
+		return true;
+	default:
+		return false;
+	}
+}
+
 /*
  * Return 0 if the superblock checksum type matches the checksum value of that
  * algorithm. Pass the raw disk superblock data.
@@ -365,33 +366,25 @@ static int btrfs_check_super_csum(struct btrfs_fs_info *fs_info,
 {
 	struct btrfs_super_block *disk_sb =
 		(struct btrfs_super_block *)raw_disk_sb;
-	u16 csum_type = btrfs_super_csum_type(disk_sb);
-	int ret = 0;
+	char result[BTRFS_CSUM_SIZE];
+	SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
 
-	if (csum_type == BTRFS_CSUM_TYPE_CRC32) {
-		u32 crc = ~(u32)0;
-		char result[sizeof(crc)];
+	shash->tfm = fs_info->csum_shash;
+	crypto_shash_init(shash);
 
-		/*
-		 * The super_block structure does not span the whole
-		 * BTRFS_SUPER_INFO_SIZE range, we expect that the unused space
-		 * is filled with zeros and is included in the checksum.
-		 */
-		crc = btrfs_csum_data(raw_disk_sb + BTRFS_CSUM_SIZE,
-				crc, BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
-		btrfs_csum_final(crc, result);
+	/*
+	 * The super_block structure does not span the whole
+	 * BTRFS_SUPER_INFO_SIZE range, we expect that the unused space is
+	 * filled with zeros and is included in the checksum.
+	 */
+	crypto_shash_update(shash, raw_disk_sb + BTRFS_CSUM_SIZE,
+			    BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
+	crypto_shash_final(shash, result);
 
-		if (memcmp(raw_disk_sb, result, sizeof(result)))
-			ret = 1;
-	}
+	if (memcmp(disk_sb->csum, result, btrfs_super_csum_size(disk_sb)))
+		return 1;
 
-	if (csum_type >= ARRAY_SIZE(btrfs_csum_sizes)) {
-		btrfs_err(fs_info, "unsupported checksum algorithm %u",
-				csum_type);
-		ret = 1;
-	}
-
-	return ret;
+	return 0;
 }
 
 int btrfs_verify_level_key(struct extent_buffer *eb, int level,
@@ -873,14 +866,13 @@ static blk_status_t btree_submit_bio_start(void *private_data, struct bio *bio,
 	return btree_csum_one_bio(bio);
 }
 
-static int check_async_write(struct btrfs_inode *bi)
+static int check_async_write(struct btrfs_fs_info *fs_info,
+			     struct btrfs_inode *bi)
 {
 	if (atomic_read(&bi->sync_writers))
 		return 0;
-#ifdef CONFIG_X86
-	if (static_cpu_has(X86_FEATURE_XMM4_2))
+	if (test_bit(BTRFS_FS_CSUM_IMPL_FAST, &fs_info->flags))
 		return 0;
-#endif
 	return 1;
 }
 
@@ -889,7 +881,7 @@ static blk_status_t btree_submit_bio_hook(struct inode *inode, struct bio *bio,
 					  unsigned long bio_flags)
 {
 	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
-	int async = check_async_write(BTRFS_I(inode));
+	int async = check_async_write(fs_info, BTRFS_I(inode));
 	blk_status_t ret;
 
 	if (bio_op(bio) != REQ_OP_WRITE) {
@@ -2262,6 +2254,29 @@ static int btrfs_init_workqueues(struct btrfs_fs_info *fs_info,
 	return 0;
 }
 
+static int btrfs_init_csum_hash(struct btrfs_fs_info *fs_info, u16 csum_type)
+{
+	struct crypto_shash *csum_shash;
+	const char *csum_name = btrfs_super_csum_name(csum_type);
+
+	csum_shash = crypto_alloc_shash(csum_name, 0, 0);
+
+	if (IS_ERR(csum_shash)) {
+		btrfs_err(fs_info, "error allocating %s hash for checksum",
+			  csum_name);
+		return PTR_ERR(csum_shash);
+	}
+
+	fs_info->csum_shash = csum_shash;
+
+	return 0;
+}
+
+static void btrfs_free_csum_hash(struct btrfs_fs_info *fs_info)
+{
+	crypto_free_shash(fs_info->csum_shash);
+}
+
 static int btrfs_replay_log(struct btrfs_fs_info *fs_info,
 			    struct btrfs_fs_devices *fs_devices)
 {
@@ -2577,7 +2592,7 @@ static int btrfs_validate_write_super(struct btrfs_fs_info *fs_info,
 	ret = validate_super(fs_info, sb, -1);
 	if (ret < 0)
 		goto out;
-	if (btrfs_super_csum_type(sb) != BTRFS_CSUM_TYPE_CRC32) {
+	if (!btrfs_supported_super_csum(btrfs_super_csum_type(sb))) {
 		ret = -EUCLEAN;
 		btrfs_err(fs_info, "invalid csum type, has %u want %u",
 			  btrfs_super_csum_type(sb), BTRFS_CSUM_TYPE_CRC32);
@@ -2607,6 +2622,7 @@ int open_ctree(struct super_block *sb,
 	u32 stripesize;
 	u64 generation;
 	u64 features;
+	u16 csum_type;
 	struct btrfs_key location;
 	struct buffer_head *bh;
 	struct btrfs_super_block *disk_super;
@@ -2689,7 +2705,7 @@ int open_ctree(struct super_block *sb,
 	INIT_LIST_HEAD(&fs_info->space_info);
 	INIT_LIST_HEAD(&fs_info->tree_mod_seq_list);
 	INIT_LIST_HEAD(&fs_info->unused_bgs);
-	btrfs_mapping_init(&fs_info->mapping_tree);
+	extent_map_tree_init(&fs_info->mapping_tree);
 	btrfs_init_block_rsv(&fs_info->global_block_rsv,
 			     BTRFS_BLOCK_RSV_GLOBAL);
 	btrfs_init_block_rsv(&fs_info->trans_block_rsv, BTRFS_BLOCK_RSV_TRANS);
@@ -2793,6 +2809,8 @@ int open_ctree(struct super_block *sb,
 	spin_lock_init(&fs_info->swapfile_pins_lock);
 	fs_info->swapfile_pins = RB_ROOT;
 
+	fs_info->send_in_progress = 0;
+
 	ret = btrfs_alloc_stripe_hash_table(fs_info);
 	if (ret) {
 		err = ret;
@@ -2813,6 +2831,25 @@ int open_ctree(struct super_block *sb,
 	}
 
 	/*
+	 * Verify the type first, if that or the the checksum value are
+	 * corrupted, we'll find out
+	 */
+	csum_type = btrfs_super_csum_type((struct btrfs_super_block *)bh->b_data);
+	if (!btrfs_supported_super_csum(csum_type)) {
+		btrfs_err(fs_info, "unsupported checksum algorithm: %u",
+			  csum_type);
+		err = -EINVAL;
+		brelse(bh);
+		goto fail_alloc;
+	}
+
+	ret = btrfs_init_csum_hash(fs_info, csum_type);
+	if (ret) {
+		err = ret;
+		goto fail_alloc;
+	}
+
+	/*
 	 * We want to check superblock checksum, the type is stored inside.
 	 * Pass the whole disk block of size BTRFS_SUPER_INFO_SIZE (4k).
 	 */
@@ -2820,7 +2857,7 @@ int open_ctree(struct super_block *sb,
 		btrfs_err(fs_info, "superblock checksum mismatch");
 		err = -EINVAL;
 		brelse(bh);
-		goto fail_alloc;
+		goto fail_csum;
 	}
 
 	/*
@@ -2857,11 +2894,11 @@ int open_ctree(struct super_block *sb,
 	if (ret) {
 		btrfs_err(fs_info, "superblock contains fatal errors");
 		err = -EINVAL;
-		goto fail_alloc;
+		goto fail_csum;
 	}
 
 	if (!btrfs_super_root(disk_super))
-		goto fail_alloc;
+		goto fail_csum;
 
 	/* check FS state, whether FS is broken. */
 	if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_ERROR)
@@ -2883,7 +2920,7 @@ int open_ctree(struct super_block *sb,
 	ret = btrfs_parse_options(fs_info, options, sb->s_flags);
 	if (ret) {
 		err = ret;
-		goto fail_alloc;
+		goto fail_csum;
 	}
 
 	features = btrfs_super_incompat_flags(disk_super) &
@@ -2893,7 +2930,7 @@ int open_ctree(struct super_block *sb,
 		    "cannot mount because of unsupported optional features (%llx)",
 		    features);
 		err = -EINVAL;
-		goto fail_alloc;
+		goto fail_csum;
 	}
 
 	features = btrfs_super_incompat_flags(disk_super);
@@ -2937,7 +2974,7 @@ int open_ctree(struct super_block *sb,
 		btrfs_err(fs_info,
 "unequal nodesize/sectorsize (%u != %u) are not allowed for mixed block groups",
 			nodesize, sectorsize);
-		goto fail_alloc;
+		goto fail_csum;
 	}
 
 	/*
@@ -2953,7 +2990,7 @@ int open_ctree(struct super_block *sb,
 	"cannot mount read-write because of unsupported optional features (%llx)",
 		       features);
 		err = -EINVAL;
-		goto fail_alloc;
+		goto fail_csum;
 	}
 
 	ret = btrfs_init_workqueues(fs_info, fs_devices);
@@ -3331,6 +3368,8 @@ fail_tree_roots:
 fail_sb_buffer:
 	btrfs_stop_all_workers(fs_info);
 	btrfs_free_block_groups(fs_info);
+fail_csum:
+	btrfs_free_csum_hash(fs_info);
 fail_alloc:
 fail_iput:
 	btrfs_mapping_tree_free(&fs_info->mapping_tree);
@@ -3472,17 +3511,20 @@ struct buffer_head *btrfs_read_dev_super(struct block_device *bdev)
 static int write_dev_supers(struct btrfs_device *device,
 			    struct btrfs_super_block *sb, int max_mirrors)
 {
+	struct btrfs_fs_info *fs_info = device->fs_info;
+	SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
 	struct buffer_head *bh;
 	int i;
 	int ret;
 	int errors = 0;
-	u32 crc;
 	u64 bytenr;
 	int op_flags;
 
 	if (max_mirrors == 0)
 		max_mirrors = BTRFS_SUPER_MIRROR_MAX;
 
+	shash->tfm = fs_info->csum_shash;
+
 	for (i = 0; i < max_mirrors; i++) {
 		bytenr = btrfs_sb_offset(i);
 		if (bytenr + BTRFS_SUPER_INFO_SIZE >=
@@ -3491,10 +3533,10 @@ static int write_dev_supers(struct btrfs_device *device,
 
 		btrfs_set_super_bytenr(sb, bytenr);
 
-		crc = ~(u32)0;
-		crc = btrfs_csum_data((const char *)sb + BTRFS_CSUM_SIZE, crc,
-				      BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
-		btrfs_csum_final(crc, sb->csum);
+		crypto_shash_init(shash);
+		crypto_shash_update(shash, (const char *)sb + BTRFS_CSUM_SIZE,
+				    BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
+		crypto_shash_final(shash, sb->csum);
 
 		/* One reference for us, and we leave it for the caller */
 		bh = __getblk(device->bdev, bytenr / BTRFS_BDEV_BLOCKSIZE,
@@ -3709,7 +3751,7 @@ int btrfs_get_num_tolerated_disk_barrier_failures(u64 flags)
 
 	if ((flags & BTRFS_BLOCK_GROUP_PROFILE_MASK) == 0 ||
 	    (flags & BTRFS_AVAIL_ALLOC_BIT_SINGLE))
-		min_tolerated = min(min_tolerated,
+		min_tolerated = min_t(int, min_tolerated,
 				    btrfs_raid_array[BTRFS_RAID_SINGLE].
 				    tolerated_failures);
 
@@ -3718,7 +3760,7 @@ int btrfs_get_num_tolerated_disk_barrier_failures(u64 flags)
 			continue;
 		if (!(flags & btrfs_raid_array[raid_type].bg_flag))
 			continue;
-		min_tolerated = min(min_tolerated,
+		min_tolerated = min_t(int, min_tolerated,
 				    btrfs_raid_array[raid_type].
 				    tolerated_failures);
 	}
diff --git a/fs/btrfs/disk-io.h b/fs/btrfs/disk-io.h
index a0161aa1ea0b..e80f7c45a307 100644
--- a/fs/btrfs/disk-io.h
+++ b/fs/btrfs/disk-io.h
@@ -115,8 +115,6 @@ int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid,
 			  int atomic);
 int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid, int level,
 		      struct btrfs_key *first_key);
-u32 btrfs_csum_data(const char *data, u32 seed, size_t len);
-void btrfs_csum_final(u32 crc, u8 *result);
 blk_status_t btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio,
 			enum btrfs_wq_endio_type metadata);
 blk_status_t btrfs_wq_submit_bio(struct btrfs_fs_info *fs_info, struct bio *bio,
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 5faf057f6f37..d3b58e388535 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -28,46 +28,12 @@
 #include "sysfs.h"
 #include "qgroup.h"
 #include "ref-verify.h"
+#include "space-info.h"
+#include "block-rsv.h"
+#include "delalloc-space.h"
 
 #undef SCRAMBLE_DELAYED_REFS
 
-/*
- * control flags for do_chunk_alloc's force field
- * CHUNK_ALLOC_NO_FORCE means to only allocate a chunk
- * if we really need one.
- *
- * CHUNK_ALLOC_LIMITED means to only try and allocate one
- * if we have very few chunks already allocated.  This is
- * used as part of the clustering code to help make sure
- * we have a good pool of storage to cluster in, without
- * filling the FS with empty chunks
- *
- * CHUNK_ALLOC_FORCE means it must try to allocate one
- *
- */
-enum {
-	CHUNK_ALLOC_NO_FORCE = 0,
-	CHUNK_ALLOC_LIMITED = 1,
-	CHUNK_ALLOC_FORCE = 2,
-};
-
-/*
- * Declare a helper function to detect underflow of various space info members
- */
-#define DECLARE_SPACE_INFO_UPDATE(name)					\
-static inline void update_##name(struct btrfs_space_info *sinfo,	\
-				 s64 bytes)				\
-{									\
-	if (bytes < 0 && sinfo->name < -bytes) {			\
-		WARN_ON(1);						\
-		sinfo->name = 0;					\
-		return;							\
-	}								\
-	sinfo->name += bytes;						\
-}
-
-DECLARE_SPACE_INFO_UPDATE(bytes_may_use);
-DECLARE_SPACE_INFO_UPDATE(bytes_pinned);
 
 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
 			       struct btrfs_delayed_ref_node *node, u64 parent,
@@ -84,21 +50,8 @@ static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
 static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
 				     struct btrfs_delayed_ref_node *node,
 				     struct btrfs_delayed_extent_op *extent_op);
-static int do_chunk_alloc(struct btrfs_trans_handle *trans, u64 flags,
-			  int force);
 static int find_next_key(struct btrfs_path *path, int level,
 			 struct btrfs_key *key);
-static void dump_space_info(struct btrfs_fs_info *fs_info,
-			    struct btrfs_space_info *info, u64 bytes,
-			    int dump_block_groups);
-static int block_rsv_use_bytes(struct btrfs_block_rsv *block_rsv,
-			       u64 num_bytes);
-static void space_info_add_new_bytes(struct btrfs_fs_info *fs_info,
-				     struct btrfs_space_info *space_info,
-				     u64 num_bytes);
-static void space_info_add_old_bytes(struct btrfs_fs_info *fs_info,
-				     struct btrfs_space_info *space_info,
-				     u64 num_bytes);
 
 static noinline int
 block_group_cache_done(struct btrfs_block_group_cache *cache)
@@ -737,62 +690,39 @@ struct btrfs_block_group_cache *btrfs_lookup_block_group(
 	return block_group_cache_tree_search(info, bytenr, 1);
 }
 
-static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info,
-						  u64 flags)
+static u64 generic_ref_to_space_flags(struct btrfs_ref *ref)
 {
-	struct list_head *head = &info->space_info;
-	struct btrfs_space_info *found;
-
-	flags &= BTRFS_BLOCK_GROUP_TYPE_MASK;
-
-	rcu_read_lock();
-	list_for_each_entry_rcu(found, head, list) {
-		if (found->flags & flags) {
-			rcu_read_unlock();
-			return found;
-		}
+	if (ref->type == BTRFS_REF_METADATA) {
+		if (ref->tree_ref.root == BTRFS_CHUNK_TREE_OBJECTID)
+			return BTRFS_BLOCK_GROUP_SYSTEM;
+		else
+			return BTRFS_BLOCK_GROUP_METADATA;
 	}
-	rcu_read_unlock();
-	return NULL;
+	return BTRFS_BLOCK_GROUP_DATA;
 }
 
 static void add_pinned_bytes(struct btrfs_fs_info *fs_info,
-			     struct btrfs_ref *ref, int sign)
+			     struct btrfs_ref *ref)
 {
 	struct btrfs_space_info *space_info;
-	s64 num_bytes;
-	u64 flags;
-
-	ASSERT(sign == 1 || sign == -1);
-	num_bytes = sign * ref->len;
-	if (ref->type == BTRFS_REF_METADATA) {
-		if (ref->tree_ref.root == BTRFS_CHUNK_TREE_OBJECTID)
-			flags = BTRFS_BLOCK_GROUP_SYSTEM;
-		else
-			flags = BTRFS_BLOCK_GROUP_METADATA;
-	} else {
-		flags = BTRFS_BLOCK_GROUP_DATA;
-	}
+	u64 flags = generic_ref_to_space_flags(ref);
 
-	space_info = __find_space_info(fs_info, flags);
+	space_info = btrfs_find_space_info(fs_info, flags);
 	ASSERT(space_info);
-	percpu_counter_add_batch(&space_info->total_bytes_pinned, num_bytes,
+	percpu_counter_add_batch(&space_info->total_bytes_pinned, ref->len,
 		    BTRFS_TOTAL_BYTES_PINNED_BATCH);
 }
 
-/*
- * after adding space to the filesystem, we need to clear the full flags
- * on all the space infos.
- */
-void btrfs_clear_space_info_full(struct btrfs_fs_info *info)
+static void sub_pinned_bytes(struct btrfs_fs_info *fs_info,
+			     struct btrfs_ref *ref)
 {
-	struct list_head *head = &info->space_info;
-	struct btrfs_space_info *found;
+	struct btrfs_space_info *space_info;
+	u64 flags = generic_ref_to_space_flags(ref);
 
-	rcu_read_lock();
-	list_for_each_entry_rcu(found, head, list)
-		found->full = 0;
-	rcu_read_unlock();
+	space_info = btrfs_find_space_info(fs_info, flags);
+	ASSERT(space_info);
+	percpu_counter_add_batch(&space_info->total_bytes_pinned, -ref->len,
+		    BTRFS_TOTAL_BYTES_PINNED_BATCH);
 }
 
 /* simple helper to search for an existing data extent at a given offset */
@@ -1121,11 +1051,11 @@ static u64 hash_extent_data_ref(u64 root_objectid, u64 owner, u64 offset)
 	__le64 lenum;
 
 	lenum = cpu_to_le64(root_objectid);
-	high_crc = crc32c(high_crc, &lenum, sizeof(lenum));
+	high_crc = btrfs_crc32c(high_crc, &lenum, sizeof(lenum));
 	lenum = cpu_to_le64(owner);
-	low_crc = crc32c(low_crc, &lenum, sizeof(lenum));
+	low_crc = btrfs_crc32c(low_crc, &lenum, sizeof(lenum));
 	lenum = cpu_to_le64(offset);
-	low_crc = crc32c(low_crc, &lenum, sizeof(lenum));
+	low_crc = btrfs_crc32c(low_crc, &lenum, sizeof(lenum));
 
 	return ((u64)high_crc << 31) ^ (u64)low_crc;
 }
@@ -2065,7 +1995,7 @@ int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
 	btrfs_ref_tree_mod(fs_info, generic_ref);
 
 	if (ret == 0 && old_ref_mod < 0 && new_ref_mod >= 0)
-		add_pinned_bytes(fs_info, generic_ref, -1);
+		sub_pinned_bytes(fs_info, generic_ref);
 
 	return ret;
 }
@@ -2462,7 +2392,7 @@ void btrfs_cleanup_ref_head_accounting(struct btrfs_fs_info *fs_info,
 			flags = BTRFS_BLOCK_GROUP_SYSTEM;
 		else
 			flags = BTRFS_BLOCK_GROUP_METADATA;
-		space_info = __find_space_info(fs_info, flags);
+		space_info = btrfs_find_space_info(fs_info, flags);
 		ASSERT(space_info);
 		percpu_counter_add_batch(&space_info->total_bytes_pinned,
 				   -head->num_bytes,
@@ -2824,49 +2754,6 @@ u64 btrfs_csum_bytes_to_leaves(struct btrfs_fs_info *fs_info, u64 csum_bytes)
 	return num_csums;
 }
 
-bool btrfs_check_space_for_delayed_refs(struct btrfs_fs_info *fs_info)
-{
-	struct btrfs_block_rsv *delayed_refs_rsv = &fs_info->delayed_refs_rsv;
-	struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
-	bool ret = false;
-	u64 reserved;
-
-	spin_lock(&global_rsv->lock);
-	reserved = global_rsv->reserved;
-	spin_unlock(&global_rsv->lock);
-
-	/*
-	 * Since the global reserve is just kind of magic we don't really want
-	 * to rely on it to save our bacon, so if our size is more than the
-	 * delayed_refs_rsv and the global rsv then it's time to think about
-	 * bailing.
-	 */
-	spin_lock(&delayed_refs_rsv->lock);
-	reserved += delayed_refs_rsv->reserved;
-	if (delayed_refs_rsv->size >= reserved)
-		ret = true;
-	spin_unlock(&delayed_refs_rsv->lock);
-	return ret;
-}
-
-int btrfs_should_throttle_delayed_refs(struct btrfs_trans_handle *trans)
-{
-	u64 num_entries =
-		atomic_read(&trans->transaction->delayed_refs.num_entries);
-	u64 avg_runtime;
-	u64 val;
-
-	smp_mb();
-	avg_runtime = trans->fs_info->avg_delayed_ref_runtime;
-	val = num_entries * avg_runtime;
-	if (val >= NSEC_PER_SEC)
-		return 1;
-	if (val >= NSEC_PER_SEC / 2)
-		return 2;
-
-	return btrfs_check_space_for_delayed_refs(trans->fs_info);
-}
-
 /*
  * this starts processing the delayed reference count updates and
  * extent insertions we have queued up so far.  count can be
@@ -3834,93 +3721,6 @@ void btrfs_wait_nocow_writers(struct btrfs_block_group_cache *bg)
 	wait_var_event(&bg->nocow_writers, !atomic_read(&bg->nocow_writers));
 }
 
-static const char *alloc_name(u64 flags)
-{
-	switch (flags) {
-	case BTRFS_BLOCK_GROUP_METADATA|BTRFS_BLOCK_GROUP_DATA:
-		return "mixed";
-	case BTRFS_BLOCK_GROUP_METADATA:
-		return "metadata";
-	case BTRFS_BLOCK_GROUP_DATA:
-		return "data";
-	case BTRFS_BLOCK_GROUP_SYSTEM:
-		return "system";
-	default:
-		WARN_ON(1);
-		return "invalid-combination";
-	};
-}
-
-static int create_space_info(struct btrfs_fs_info *info, u64 flags)
-{
-
-	struct btrfs_space_info *space_info;
-	int i;
-	int ret;
-
-	space_info = kzalloc(sizeof(*space_info), GFP_NOFS);
-	if (!space_info)
-		return -ENOMEM;
-
-	ret = percpu_counter_init(&space_info->total_bytes_pinned, 0,
-				 GFP_KERNEL);
-	if (ret) {
-		kfree(space_info);
-		return ret;
-	}
-
-	for (i = 0; i < BTRFS_NR_RAID_TYPES; i++)
-		INIT_LIST_HEAD(&space_info->block_groups[i]);
-	init_rwsem(&space_info->groups_sem);
-	spin_lock_init(&space_info->lock);
-	space_info->flags = flags & BTRFS_BLOCK_GROUP_TYPE_MASK;
-	space_info->force_alloc = CHUNK_ALLOC_NO_FORCE;
-	init_waitqueue_head(&space_info->wait);
-	INIT_LIST_HEAD(&space_info->ro_bgs);
-	INIT_LIST_HEAD(&space_info->tickets);
-	INIT_LIST_HEAD(&space_info->priority_tickets);
-
-	ret = kobject_init_and_add(&space_info->kobj, &space_info_ktype,
-				    info->space_info_kobj, "%s",
-				    alloc_name(space_info->flags));
-	if (ret) {
-		kobject_put(&space_info->kobj);
-		return ret;
-	}
-
-	list_add_rcu(&space_info->list, &info->space_info);
-	if (flags & BTRFS_BLOCK_GROUP_DATA)
-		info->data_sinfo = space_info;
-
-	return ret;
-}
-
-static void update_space_info(struct btrfs_fs_info *info, u64 flags,
-			     u64 total_bytes, u64 bytes_used,
-			     u64 bytes_readonly,
-			     struct btrfs_space_info **space_info)
-{
-	struct btrfs_space_info *found;
-	int factor;
-
-	factor = btrfs_bg_type_to_factor(flags);
-
-	found = __find_space_info(info, flags);
-	ASSERT(found);
-	spin_lock(&found->lock);
-	found->total_bytes += total_bytes;
-	found->disk_total += total_bytes * factor;
-	found->bytes_used += bytes_used;
-	found->disk_used += bytes_used * factor;
-	found->bytes_readonly += bytes_readonly;
-	if (total_bytes > 0)
-		found->full = 0;
-	space_info_add_new_bytes(info, found, total_bytes -
-				 bytes_used - bytes_readonly);
-	spin_unlock(&found->lock);
-	*space_info = found;
-}
-
 static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
 {
 	u64 extra_flags = chunk_to_extended(flags) &
@@ -4068,215 +3868,6 @@ u64 btrfs_system_alloc_profile(struct btrfs_fs_info *fs_info)
 	return get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
 }
 
-static u64 btrfs_space_info_used(struct btrfs_space_info *s_info,
-				 bool may_use_included)
-{
-	ASSERT(s_info);
-	return s_info->bytes_used + s_info->bytes_reserved +
-		s_info->bytes_pinned + s_info->bytes_readonly +
-		(may_use_included ? s_info->bytes_may_use : 0);
-}
-
-int btrfs_alloc_data_chunk_ondemand(struct btrfs_inode *inode, u64 bytes)
-{
-	struct btrfs_root *root = inode->root;
-	struct btrfs_fs_info *fs_info = root->fs_info;
-	struct btrfs_space_info *data_sinfo = fs_info->data_sinfo;
-	u64 used;
-	int ret = 0;
-	int need_commit = 2;
-	int have_pinned_space;
-
-	/* make sure bytes are sectorsize aligned */
-	bytes = ALIGN(bytes, fs_info->sectorsize);
-
-	if (btrfs_is_free_space_inode(inode)) {
-		need_commit = 0;
-		ASSERT(current->journal_info);
-	}
-
-again:
-	/* make sure we have enough space to handle the data first */
-	spin_lock(&data_sinfo->lock);
-	used = btrfs_space_info_used(data_sinfo, true);
-
-	if (used + bytes > data_sinfo->total_bytes) {
-		struct btrfs_trans_handle *trans;
-
-		/*
-		 * if we don't have enough free bytes in this space then we need
-		 * to alloc a new chunk.
-		 */
-		if (!data_sinfo->full) {
-			u64 alloc_target;
-
-			data_sinfo->force_alloc = CHUNK_ALLOC_FORCE;
-			spin_unlock(&data_sinfo->lock);
-
-			alloc_target = btrfs_data_alloc_profile(fs_info);
-			/*
-			 * It is ugly that we don't call nolock join
-			 * transaction for the free space inode case here.
-			 * But it is safe because we only do the data space
-			 * reservation for the free space cache in the
-			 * transaction context, the common join transaction
-			 * just increase the counter of the current transaction
-			 * handler, doesn't try to acquire the trans_lock of
-			 * the fs.
-			 */
-			trans = btrfs_join_transaction(root);
-			if (IS_ERR(trans))
-				return PTR_ERR(trans);
-
-			ret = do_chunk_alloc(trans, alloc_target,
-					     CHUNK_ALLOC_NO_FORCE);
-			btrfs_end_transaction(trans);
-			if (ret < 0) {
-				if (ret != -ENOSPC)
-					return ret;
-				else {
-					have_pinned_space = 1;
-					goto commit_trans;
-				}
-			}
-
-			goto again;
-		}
-
-		/*
-		 * If we don't have enough pinned space to deal with this
-		 * allocation, and no removed chunk in current transaction,
-		 * don't bother committing the transaction.
-		 */
-		have_pinned_space = __percpu_counter_compare(
-			&data_sinfo->total_bytes_pinned,
-			used + bytes - data_sinfo->total_bytes,
-			BTRFS_TOTAL_BYTES_PINNED_BATCH);
-		spin_unlock(&data_sinfo->lock);
-
-		/* commit the current transaction and try again */
-commit_trans:
-		if (need_commit) {
-			need_commit--;
-
-			if (need_commit > 0) {
-				btrfs_start_delalloc_roots(fs_info, -1);
-				btrfs_wait_ordered_roots(fs_info, U64_MAX, 0,
-							 (u64)-1);
-			}
-
-			trans = btrfs_join_transaction(root);
-			if (IS_ERR(trans))
-				return PTR_ERR(trans);
-			if (have_pinned_space >= 0 ||
-			    test_bit(BTRFS_TRANS_HAVE_FREE_BGS,
-				     &trans->transaction->flags) ||
-			    need_commit > 0) {
-				ret = btrfs_commit_transaction(trans);
-				if (ret)
-					return ret;
-				/*
-				 * The cleaner kthread might still be doing iput
-				 * operations. Wait for it to finish so that
-				 * more space is released.  We don't need to
-				 * explicitly run the delayed iputs here because
-				 * the commit_transaction would have woken up
-				 * the cleaner.
-				 */
-				ret = btrfs_wait_on_delayed_iputs(fs_info);
-				if (ret)
-					return ret;
-				goto again;
-			} else {
-				btrfs_end_transaction(trans);
-			}
-		}
-
-		trace_btrfs_space_reservation(fs_info,
-					      "space_info:enospc",
-					      data_sinfo->flags, bytes, 1);
-		return -ENOSPC;
-	}
-	update_bytes_may_use(data_sinfo, bytes);
-	trace_btrfs_space_reservation(fs_info, "space_info",
-				      data_sinfo->flags, bytes, 1);
-	spin_unlock(&data_sinfo->lock);
-
-	return 0;
-}
-
-int btrfs_check_data_free_space(struct inode *inode,
-			struct extent_changeset **reserved, u64 start, u64 len)
-{
-	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
-	int ret;
-
-	/* align the range */
-	len = round_up(start + len, fs_info->sectorsize) -
-	      round_down(start, fs_info->sectorsize);
-	start = round_down(start, fs_info->sectorsize);
-
-	ret = btrfs_alloc_data_chunk_ondemand(BTRFS_I(inode), len);
-	if (ret < 0)
-		return ret;
-
-	/* Use new btrfs_qgroup_reserve_data to reserve precious data space. */
-	ret = btrfs_qgroup_reserve_data(inode, reserved, start, len);
-	if (ret < 0)
-		btrfs_free_reserved_data_space_noquota(inode, start, len);
-	else
-		ret = 0;
-	return ret;
-}
-
-/*
- * Called if we need to clear a data reservation for this inode
- * Normally in a error case.
- *
- * This one will *NOT* use accurate qgroup reserved space API, just for case
- * which we can't sleep and is sure it won't affect qgroup reserved space.
- * Like clear_bit_hook().
- */
-void btrfs_free_reserved_data_space_noquota(struct inode *inode, u64 start,
-					    u64 len)
-{
-	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
-	struct btrfs_space_info *data_sinfo;
-
-	/* Make sure the range is aligned to sectorsize */
-	len = round_up(start + len, fs_info->sectorsize) -
-	      round_down(start, fs_info->sectorsize);
-	start = round_down(start, fs_info->sectorsize);
-
-	data_sinfo = fs_info->data_sinfo;
-	spin_lock(&data_sinfo->lock);
-	update_bytes_may_use(data_sinfo, -len);
-	trace_btrfs_space_reservation(fs_info, "space_info",
-				      data_sinfo->flags, len, 0);
-	spin_unlock(&data_sinfo->lock);
-}
-
-/*
- * Called if we need to clear a data reservation for this inode
- * Normally in a error case.
- *
- * This one will handle the per-inode data rsv map for accurate reserved
- * space framework.
- */
-void btrfs_free_reserved_data_space(struct inode *inode,
-			struct extent_changeset *reserved, u64 start, u64 len)
-{
-	struct btrfs_root *root = BTRFS_I(inode)->root;
-
-	/* Make sure the range is aligned to sectorsize */
-	len = round_up(start + len, root->fs_info->sectorsize) -
-	      round_down(start, root->fs_info->sectorsize);
-	start = round_down(start, root->fs_info->sectorsize);
-
-	btrfs_free_reserved_data_space_noquota(inode, start, len);
-	btrfs_qgroup_free_data(inode, reserved, start, len);
-}
-
 static void force_metadata_allocation(struct btrfs_fs_info *info)
 {
 	struct list_head *head = &info->space_info;
@@ -4290,11 +3881,6 @@ static void force_metadata_allocation(struct btrfs_fs_info *info)
 	rcu_read_unlock();
 }
 
-static inline u64 calc_global_rsv_need_space(struct btrfs_block_rsv *global)
-{
-	return (global->size << 1);
-}
-
 static int should_alloc_chunk(struct btrfs_fs_info *fs_info,
 			      struct btrfs_space_info *sinfo, int force)
 {
@@ -4325,15 +3911,9 @@ static u64 get_profile_num_devs(struct btrfs_fs_info *fs_info, u64 type)
 {
 	u64 num_dev;
 
-	if (type & (BTRFS_BLOCK_GROUP_RAID10 |
-		    BTRFS_BLOCK_GROUP_RAID0 |
-		    BTRFS_BLOCK_GROUP_RAID5 |
-		    BTRFS_BLOCK_GROUP_RAID6))
+	num_dev = btrfs_raid_array[btrfs_bg_flags_to_raid_index(type)].devs_max;
+	if (!num_dev)
 		num_dev = fs_info->fs_devices->rw_devices;
-	else if (type & BTRFS_BLOCK_GROUP_RAID1)
-		num_dev = 2;
-	else
-		num_dev = 1;	/* DUP or single */
 
 	return num_dev;
 }
@@ -4358,7 +3938,7 @@ void check_system_chunk(struct btrfs_trans_handle *trans, u64 type)
 	 */
 	lockdep_assert_held(&fs_info->chunk_mutex);
 
-	info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
+	info = btrfs_find_space_info(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
 	spin_lock(&info->lock);
 	left = info->total_bytes - btrfs_space_info_used(info, true);
 	spin_unlock(&info->lock);
@@ -4372,7 +3952,7 @@ void check_system_chunk(struct btrfs_trans_handle *trans, u64 type)
 	if (left < thresh && btrfs_test_opt(fs_info, ENOSPC_DEBUG)) {
 		btrfs_info(fs_info, "left=%llu, need=%llu, flags=%llu",
 			   left, thresh, type);
-		dump_space_info(fs_info, info, 0, 0);
+		btrfs_dump_space_info(fs_info, info, 0, 0);
 	}
 
 	if (left < thresh) {
@@ -4405,8 +3985,8 @@ void check_system_chunk(struct btrfs_trans_handle *trans, u64 type)
  *    - return 1 if it successfully allocates a chunk,
  *    - return errors including -ENOSPC otherwise.
  */
-static int do_chunk_alloc(struct btrfs_trans_handle *trans, u64 flags,
-			  int force)
+int btrfs_chunk_alloc(struct btrfs_trans_handle *trans, u64 flags,
+		      enum btrfs_chunk_alloc_enum force)
 {
 	struct btrfs_fs_info *fs_info = trans->fs_info;
 	struct btrfs_space_info *space_info;
@@ -4418,7 +3998,7 @@ static int do_chunk_alloc(struct btrfs_trans_handle *trans, u64 flags,
 	if (trans->allocating_chunk)
 		return -ENOSPC;
 
-	space_info = __find_space_info(fs_info, flags);
+	space_info = btrfs_find_space_info(fs_info, flags);
 	ASSERT(space_info);
 
 	do {
@@ -4525,1714 +4105,6 @@ out:
 	return ret;
 }
 
-static int can_overcommit(struct btrfs_fs_info *fs_info,
-			  struct btrfs_space_info *space_info, u64 bytes,
-			  enum btrfs_reserve_flush_enum flush,
-			  bool system_chunk)
-{
-	struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
-	u64 profile;
-	u64 space_size;
-	u64 avail;
-	u64 used;
-	int factor;
-
-	/* Don't overcommit when in mixed mode. */
-	if (space_info->flags & BTRFS_BLOCK_GROUP_DATA)
-		return 0;
-
-	if (system_chunk)
-		profile = btrfs_system_alloc_profile(fs_info);
-	else
-		profile = btrfs_metadata_alloc_profile(fs_info);
-
-	used = btrfs_space_info_used(space_info, false);
-
-	/*
-	 * We only want to allow over committing if we have lots of actual space
-	 * free, but if we don't have enough space to handle the global reserve
-	 * space then we could end up having a real enospc problem when trying
-	 * to allocate a chunk or some other such important allocation.
-	 */
-	spin_lock(&global_rsv->lock);
-	space_size = calc_global_rsv_need_space(global_rsv);
-	spin_unlock(&global_rsv->lock);
-	if (used + space_size >= space_info->total_bytes)
-		return 0;
-
-	used += space_info->bytes_may_use;
-
-	avail = atomic64_read(&fs_info->free_chunk_space);
-
-	/*
-	 * If we have dup, raid1 or raid10 then only half of the free
-	 * space is actually usable.  For raid56, the space info used
-	 * doesn't include the parity drive, so we don't have to
-	 * change the math
-	 */
-	factor = btrfs_bg_type_to_factor(profile);
-	avail = div_u64(avail, factor);
-
-	/*
-	 * If we aren't flushing all things, let us overcommit up to
-	 * 1/2th of the space. If we can flush, don't let us overcommit
-	 * too much, let it overcommit up to 1/8 of the space.
-	 */
-	if (flush == BTRFS_RESERVE_FLUSH_ALL)
-		avail >>= 3;
-	else
-		avail >>= 1;
-
-	if (used + bytes < space_info->total_bytes + avail)
-		return 1;
-	return 0;
-}
-
-static void btrfs_writeback_inodes_sb_nr(struct btrfs_fs_info *fs_info,
-					 unsigned long nr_pages, int nr_items)
-{
-	struct super_block *sb = fs_info->sb;
-
-	if (down_read_trylock(&sb->s_umount)) {
-		writeback_inodes_sb_nr(sb, nr_pages, WB_REASON_FS_FREE_SPACE);
-		up_read(&sb->s_umount);
-	} else {
-		/*
-		 * We needn't worry the filesystem going from r/w to r/o though
-		 * we don't acquire ->s_umount mutex, because the filesystem
-		 * should guarantee the delalloc inodes list be empty after
-		 * the filesystem is readonly(all dirty pages are written to
-		 * the disk).
-		 */
-		btrfs_start_delalloc_roots(fs_info, nr_items);
-		if (!current->journal_info)
-			btrfs_wait_ordered_roots(fs_info, nr_items, 0, (u64)-1);
-	}
-}
-
-static inline u64 calc_reclaim_items_nr(struct btrfs_fs_info *fs_info,
-					u64 to_reclaim)
-{
-	u64 bytes;
-	u64 nr;
-
-	bytes = btrfs_calc_trans_metadata_size(fs_info, 1);
-	nr = div64_u64(to_reclaim, bytes);
-	if (!nr)
-		nr = 1;
-	return nr;
-}
-
-#define EXTENT_SIZE_PER_ITEM	SZ_256K
-
-/*
- * shrink metadata reservation for delalloc
- */
-static void shrink_delalloc(struct btrfs_fs_info *fs_info, u64 to_reclaim,
-			    u64 orig, bool wait_ordered)
-{
-	struct btrfs_space_info *space_info;
-	struct btrfs_trans_handle *trans;
-	u64 delalloc_bytes;
-	u64 dio_bytes;
-	u64 async_pages;
-	u64 items;
-	long time_left;
-	unsigned long nr_pages;
-	int loops;
-
-	/* Calc the number of the pages we need flush for space reservation */
-	items = calc_reclaim_items_nr(fs_info, to_reclaim);
-	to_reclaim = items * EXTENT_SIZE_PER_ITEM;
-
-	trans = (struct btrfs_trans_handle *)current->journal_info;
-	space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
-
-	delalloc_bytes = percpu_counter_sum_positive(
-						&fs_info->delalloc_bytes);
-	dio_bytes = percpu_counter_sum_positive(&fs_info->dio_bytes);
-	if (delalloc_bytes == 0 && dio_bytes == 0) {
-		if (trans)
-			return;
-		if (wait_ordered)
-			btrfs_wait_ordered_roots(fs_info, items, 0, (u64)-1);
-		return;
-	}
-
-	/*
-	 * If we are doing more ordered than delalloc we need to just wait on
-	 * ordered extents, otherwise we'll waste time trying to flush delalloc
-	 * that likely won't give us the space back we need.
-	 */
-	if (dio_bytes > delalloc_bytes)
-		wait_ordered = true;
-
-	loops = 0;
-	while ((delalloc_bytes || dio_bytes) && loops < 3) {
-		nr_pages = min(delalloc_bytes, to_reclaim) >> PAGE_SHIFT;
-
-		/*
-		 * Triggers inode writeback for up to nr_pages. This will invoke
-		 * ->writepages callback and trigger delalloc filling
-		 *  (btrfs_run_delalloc_range()).
-		 */
-		btrfs_writeback_inodes_sb_nr(fs_info, nr_pages, items);
-
-		/*
-		 * We need to wait for the compressed pages to start before
-		 * we continue.
-		 */
-		async_pages = atomic_read(&fs_info->async_delalloc_pages);
-		if (!async_pages)
-			goto skip_async;
-
-		/*
-		 * Calculate how many compressed pages we want to be written
-		 * before we continue. I.e if there are more async pages than we
-		 * require wait_event will wait until nr_pages are written.
-		 */
-		if (async_pages <= nr_pages)
-			async_pages = 0;
-		else
-			async_pages -= nr_pages;
-
-		wait_event(fs_info->async_submit_wait,
-			   atomic_read(&fs_info->async_delalloc_pages) <=
-			   (int)async_pages);
-skip_async:
-		spin_lock(&space_info->lock);
-		if (list_empty(&space_info->tickets) &&
-		    list_empty(&space_info->priority_tickets)) {
-			spin_unlock(&space_info->lock);
-			break;
-		}
-		spin_unlock(&space_info->lock);
-
-		loops++;
-		if (wait_ordered && !trans) {
-			btrfs_wait_ordered_roots(fs_info, items, 0, (u64)-1);
-		} else {
-			time_left = schedule_timeout_killable(1);
-			if (time_left)
-				break;
-		}
-		delalloc_bytes = percpu_counter_sum_positive(
-						&fs_info->delalloc_bytes);
-		dio_bytes = percpu_counter_sum_positive(&fs_info->dio_bytes);
-	}
-}
-
-struct reserve_ticket {
-	u64 orig_bytes;
-	u64 bytes;
-	int error;
-	struct list_head list;
-	wait_queue_head_t wait;
-};
-
-/**
- * maybe_commit_transaction - possibly commit the transaction if its ok to
- * @root - the root we're allocating for
- * @bytes - the number of bytes we want to reserve
- * @force - force the commit
- *
- * This will check to make sure that committing the transaction will actually
- * get us somewhere and then commit the transaction if it does.  Otherwise it
- * will return -ENOSPC.
- */
-static int may_commit_transaction(struct btrfs_fs_info *fs_info,
-				  struct btrfs_space_info *space_info)
-{
-	struct reserve_ticket *ticket = NULL;
-	struct btrfs_block_rsv *delayed_rsv = &fs_info->delayed_block_rsv;
-	struct btrfs_block_rsv *delayed_refs_rsv = &fs_info->delayed_refs_rsv;
-	struct btrfs_trans_handle *trans;
-	u64 bytes_needed;
-	u64 reclaim_bytes = 0;
-
-	trans = (struct btrfs_trans_handle *)current->journal_info;
-	if (trans)
-		return -EAGAIN;
-
-	spin_lock(&space_info->lock);
-	if (!list_empty(&space_info->priority_tickets))
-		ticket = list_first_entry(&space_info->priority_tickets,
-					  struct reserve_ticket, list);
-	else if (!list_empty(&space_info->tickets))
-		ticket = list_first_entry(&space_info->tickets,
-					  struct reserve_ticket, list);
-	bytes_needed = (ticket) ? ticket->bytes : 0;
-	spin_unlock(&space_info->lock);
-
-	if (!bytes_needed)
-		return 0;
-
-	trans = btrfs_join_transaction(fs_info->extent_root);
-	if (IS_ERR(trans))
-		return PTR_ERR(trans);
-
-	/*
-	 * See if there is enough pinned space to make this reservation, or if
-	 * we have block groups that are going to be freed, allowing us to
-	 * possibly do a chunk allocation the next loop through.
-	 */
-	if (test_bit(BTRFS_TRANS_HAVE_FREE_BGS, &trans->transaction->flags) ||
-	    __percpu_counter_compare(&space_info->total_bytes_pinned,
-				     bytes_needed,
-				     BTRFS_TOTAL_BYTES_PINNED_BATCH) >= 0)
-		goto commit;
-
-	/*
-	 * See if there is some space in the delayed insertion reservation for
-	 * this reservation.
-	 */
-	if (space_info != delayed_rsv->space_info)
-		goto enospc;
-
-	spin_lock(&delayed_rsv->lock);
-	reclaim_bytes += delayed_rsv->reserved;
-	spin_unlock(&delayed_rsv->lock);
-
-	spin_lock(&delayed_refs_rsv->lock);
-	reclaim_bytes += delayed_refs_rsv->reserved;
-	spin_unlock(&delayed_refs_rsv->lock);
-	if (reclaim_bytes >= bytes_needed)
-		goto commit;
-	bytes_needed -= reclaim_bytes;
-
-	if (__percpu_counter_compare(&space_info->total_bytes_pinned,
-				   bytes_needed,
-				   BTRFS_TOTAL_BYTES_PINNED_BATCH) < 0)
-		goto enospc;
-
-commit:
-	return btrfs_commit_transaction(trans);
-enospc:
-	btrfs_end_transaction(trans);
-	return -ENOSPC;
-}
-
-/*
- * Try to flush some data based on policy set by @state. This is only advisory
- * and may fail for various reasons. The caller is supposed to examine the
- * state of @space_info to detect the outcome.
- */
-static void flush_space(struct btrfs_fs_info *fs_info,
-		       struct btrfs_space_info *space_info, u64 num_bytes,
-		       int state)
-{
-	struct btrfs_root *root = fs_info->extent_root;
-	struct btrfs_trans_handle *trans;
-	int nr;
-	int ret = 0;
-
-	switch (state) {
-	case FLUSH_DELAYED_ITEMS_NR:
-	case FLUSH_DELAYED_ITEMS:
-		if (state == FLUSH_DELAYED_ITEMS_NR)
-			nr = calc_reclaim_items_nr(fs_info, num_bytes) * 2;
-		else
-			nr = -1;
-
-		trans = btrfs_join_transaction(root);
-		if (IS_ERR(trans)) {
-			ret = PTR_ERR(trans);
-			break;
-		}
-		ret = btrfs_run_delayed_items_nr(trans, nr);
-		btrfs_end_transaction(trans);
-		break;
-	case FLUSH_DELALLOC:
-	case FLUSH_DELALLOC_WAIT:
-		shrink_delalloc(fs_info, num_bytes * 2, num_bytes,
-				state == FLUSH_DELALLOC_WAIT);
-		break;
-	case FLUSH_DELAYED_REFS_NR:
-	case FLUSH_DELAYED_REFS:
-		trans = btrfs_join_transaction(root);
-		if (IS_ERR(trans)) {
-			ret = PTR_ERR(trans);
-			break;
-		}
-		if (state == FLUSH_DELAYED_REFS_NR)
-			nr = calc_reclaim_items_nr(fs_info, num_bytes);
-		else
-			nr = 0;
-		btrfs_run_delayed_refs(trans, nr);
-		btrfs_end_transaction(trans);
-		break;
-	case ALLOC_CHUNK:
-	case ALLOC_CHUNK_FORCE:
-		trans = btrfs_join_transaction(root);
-		if (IS_ERR(trans)) {
-			ret = PTR_ERR(trans);
-			break;
-		}
-		ret = do_chunk_alloc(trans,
-				     btrfs_metadata_alloc_profile(fs_info),
-				     (state == ALLOC_CHUNK) ?
-				      CHUNK_ALLOC_NO_FORCE : CHUNK_ALLOC_FORCE);
-		btrfs_end_transaction(trans);
-		if (ret > 0 || ret == -ENOSPC)
-			ret = 0;
-		break;
-	case COMMIT_TRANS:
-		/*
-		 * If we have pending delayed iputs then we could free up a
-		 * bunch of pinned space, so make sure we run the iputs before
-		 * we do our pinned bytes check below.
-		 */
-		btrfs_run_delayed_iputs(fs_info);
-		btrfs_wait_on_delayed_iputs(fs_info);
-
-		ret = may_commit_transaction(fs_info, space_info);
-		break;
-	default:
-		ret = -ENOSPC;
-		break;
-	}
-
-	trace_btrfs_flush_space(fs_info, space_info->flags, num_bytes, state,
-				ret);
-	return;
-}
-
-static inline u64
-btrfs_calc_reclaim_metadata_size(struct btrfs_fs_info *fs_info,
-				 struct btrfs_space_info *space_info,
-				 bool system_chunk)
-{
-	struct reserve_ticket *ticket;
-	u64 used;
-	u64 expected;
-	u64 to_reclaim = 0;
-
-	list_for_each_entry(ticket, &space_info->tickets, list)
-		to_reclaim += ticket->bytes;
-	list_for_each_entry(ticket, &space_info->priority_tickets, list)
-		to_reclaim += ticket->bytes;
-	if (to_reclaim)
-		return to_reclaim;
-
-	to_reclaim = min_t(u64, num_online_cpus() * SZ_1M, SZ_16M);
-	if (can_overcommit(fs_info, space_info, to_reclaim,
-			   BTRFS_RESERVE_FLUSH_ALL, system_chunk))
-		return 0;
-
-	used = btrfs_space_info_used(space_info, true);
-
-	if (can_overcommit(fs_info, space_info, SZ_1M,
-			   BTRFS_RESERVE_FLUSH_ALL, system_chunk))
-		expected = div_factor_fine(space_info->total_bytes, 95);
-	else
-		expected = div_factor_fine(space_info->total_bytes, 90);
-
-	if (used > expected)
-		to_reclaim = used - expected;
-	else
-		to_reclaim = 0;
-	to_reclaim = min(to_reclaim, space_info->bytes_may_use +
-				     space_info->bytes_reserved);
-	return to_reclaim;
-}
-
-static inline int need_do_async_reclaim(struct btrfs_fs_info *fs_info,
-					struct btrfs_space_info *space_info,
-					u64 used, bool system_chunk)
-{
-	u64 thresh = div_factor_fine(space_info->total_bytes, 98);
-
-	/* If we're just plain full then async reclaim just slows us down. */
-	if ((space_info->bytes_used + space_info->bytes_reserved) >= thresh)
-		return 0;
-
-	if (!btrfs_calc_reclaim_metadata_size(fs_info, space_info,
-					      system_chunk))
-		return 0;
-
-	return (used >= thresh && !btrfs_fs_closing(fs_info) &&
-		!test_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state));
-}
-
-static bool wake_all_tickets(struct list_head *head)
-{
-	struct reserve_ticket *ticket;
-
-	while (!list_empty(head)) {
-		ticket = list_first_entry(head, struct reserve_ticket, list);
-		list_del_init(&ticket->list);
-		ticket->error = -ENOSPC;
-		wake_up(&ticket->wait);
-		if (ticket->bytes != ticket->orig_bytes)
-			return true;
-	}
-	return false;
-}
-
-/*
- * This is for normal flushers, we can wait all goddamned day if we want to.  We
- * will loop and continuously try to flush as long as we are making progress.
- * We count progress as clearing off tickets each time we have to loop.
- */
-static void btrfs_async_reclaim_metadata_space(struct work_struct *work)
-{
-	struct btrfs_fs_info *fs_info;
-	struct btrfs_space_info *space_info;
-	u64 to_reclaim;
-	int flush_state;
-	int commit_cycles = 0;
-	u64 last_tickets_id;
-
-	fs_info = container_of(work, struct btrfs_fs_info, async_reclaim_work);
-	space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
-
-	spin_lock(&space_info->lock);
-	to_reclaim = btrfs_calc_reclaim_metadata_size(fs_info, space_info,
-						      false);
-	if (!to_reclaim) {
-		space_info->flush = 0;
-		spin_unlock(&space_info->lock);
-		return;
-	}
-	last_tickets_id = space_info->tickets_id;
-	spin_unlock(&space_info->lock);
-
-	flush_state = FLUSH_DELAYED_ITEMS_NR;
-	do {
-		flush_space(fs_info, space_info, to_reclaim, flush_state);
-		spin_lock(&space_info->lock);
-		if (list_empty(&space_info->tickets)) {
-			space_info->flush = 0;
-			spin_unlock(&space_info->lock);
-			return;
-		}
-		to_reclaim = btrfs_calc_reclaim_metadata_size(fs_info,
-							      space_info,
-							      false);
-		if (last_tickets_id == space_info->tickets_id) {
-			flush_state++;
-		} else {
-			last_tickets_id = space_info->tickets_id;
-			flush_state = FLUSH_DELAYED_ITEMS_NR;
-			if (commit_cycles)
-				commit_cycles--;
-		}
-
-		/*
-		 * We don't want to force a chunk allocation until we've tried
-		 * pretty hard to reclaim space.  Think of the case where we
-		 * freed up a bunch of space and so have a lot of pinned space
-		 * to reclaim.  We would rather use that than possibly create a
-		 * underutilized metadata chunk.  So if this is our first run
-		 * through the flushing state machine skip ALLOC_CHUNK_FORCE and
-		 * commit the transaction.  If nothing has changed the next go
-		 * around then we can force a chunk allocation.
-		 */
-		if (flush_state == ALLOC_CHUNK_FORCE && !commit_cycles)
-			flush_state++;
-
-		if (flush_state > COMMIT_TRANS) {
-			commit_cycles++;
-			if (commit_cycles > 2) {
-				if (wake_all_tickets(&space_info->tickets)) {
-					flush_state = FLUSH_DELAYED_ITEMS_NR;
-					commit_cycles--;
-				} else {
-					space_info->flush = 0;
-				}
-			} else {
-				flush_state = FLUSH_DELAYED_ITEMS_NR;
-			}
-		}
-		spin_unlock(&space_info->lock);
-	} while (flush_state <= COMMIT_TRANS);
-}
-
-void btrfs_init_async_reclaim_work(struct work_struct *work)
-{
-	INIT_WORK(work, btrfs_async_reclaim_metadata_space);
-}
-
-static const enum btrfs_flush_state priority_flush_states[] = {
-	FLUSH_DELAYED_ITEMS_NR,
-	FLUSH_DELAYED_ITEMS,
-	ALLOC_CHUNK,
-};
-
-static void priority_reclaim_metadata_space(struct btrfs_fs_info *fs_info,
-					    struct btrfs_space_info *space_info,
-					    struct reserve_ticket *ticket)
-{
-	u64 to_reclaim;
-	int flush_state;
-
-	spin_lock(&space_info->lock);
-	to_reclaim = btrfs_calc_reclaim_metadata_size(fs_info, space_info,
-						      false);
-	if (!to_reclaim) {
-		spin_unlock(&space_info->lock);
-		return;
-	}
-	spin_unlock(&space_info->lock);
-
-	flush_state = 0;
-	do {
-		flush_space(fs_info, space_info, to_reclaim,
-			    priority_flush_states[flush_state]);
-		flush_state++;
-		spin_lock(&space_info->lock);
-		if (ticket->bytes == 0) {
-			spin_unlock(&space_info->lock);
-			return;
-		}
-		spin_unlock(&space_info->lock);
-	} while (flush_state < ARRAY_SIZE(priority_flush_states));
-}
-
-static int wait_reserve_ticket(struct btrfs_fs_info *fs_info,
-			       struct btrfs_space_info *space_info,
-			       struct reserve_ticket *ticket)
-
-{
-	DEFINE_WAIT(wait);
-	u64 reclaim_bytes = 0;
-	int ret = 0;
-
-	spin_lock(&space_info->lock);
-	while (ticket->bytes > 0 && ticket->error == 0) {
-		ret = prepare_to_wait_event(&ticket->wait, &wait, TASK_KILLABLE);
-		if (ret) {
-			ret = -EINTR;
-			break;
-		}
-		spin_unlock(&space_info->lock);
-
-		schedule();
-
-		finish_wait(&ticket->wait, &wait);
-		spin_lock(&space_info->lock);
-	}
-	if (!ret)
-		ret = ticket->error;
-	if (!list_empty(&ticket->list))
-		list_del_init(&ticket->list);
-	if (ticket->bytes && ticket->bytes < ticket->orig_bytes)
-		reclaim_bytes = ticket->orig_bytes - ticket->bytes;
-	spin_unlock(&space_info->lock);
-
-	if (reclaim_bytes)
-		space_info_add_old_bytes(fs_info, space_info, reclaim_bytes);
-	return ret;
-}
-
-/**
- * reserve_metadata_bytes - try to reserve bytes from the block_rsv's space
- * @root - the root we're allocating for
- * @space_info - the space info we want to allocate from
- * @orig_bytes - the number of bytes we want
- * @flush - whether or not we can flush to make our reservation
- *
- * This will reserve orig_bytes number of bytes from the space info associated
- * with the block_rsv.  If there is not enough space it will make an attempt to
- * flush out space to make room.  It will do this by flushing delalloc if
- * possible or committing the transaction.  If flush is 0 then no attempts to
- * regain reservations will be made and this will fail if there is not enough
- * space already.
- */
-static int __reserve_metadata_bytes(struct btrfs_fs_info *fs_info,
-				    struct btrfs_space_info *space_info,
-				    u64 orig_bytes,
-				    enum btrfs_reserve_flush_enum flush,
-				    bool system_chunk)
-{
-	struct reserve_ticket ticket;
-	u64 used;
-	u64 reclaim_bytes = 0;
-	int ret = 0;
-
-	ASSERT(orig_bytes);
-	ASSERT(!current->journal_info || flush != BTRFS_RESERVE_FLUSH_ALL);
-
-	spin_lock(&space_info->lock);
-	ret = -ENOSPC;
-	used = btrfs_space_info_used(space_info, true);
-
-	/*
-	 * If we have enough space then hooray, make our reservation and carry
-	 * on.  If not see if we can overcommit, and if we can, hooray carry on.
-	 * If not things get more complicated.
-	 */
-	if (used + orig_bytes <= space_info->total_bytes) {
-		update_bytes_may_use(space_info, orig_bytes);
-		trace_btrfs_space_reservation(fs_info, "space_info",
-					      space_info->flags, orig_bytes, 1);
-		ret = 0;
-	} else if (can_overcommit(fs_info, space_info, orig_bytes, flush,
-				  system_chunk)) {
-		update_bytes_may_use(space_info, orig_bytes);
-		trace_btrfs_space_reservation(fs_info, "space_info",
-					      space_info->flags, orig_bytes, 1);
-		ret = 0;
-	}
-
-	/*
-	 * If we couldn't make a reservation then setup our reservation ticket
-	 * and kick the async worker if it's not already running.
-	 *
-	 * If we are a priority flusher then we just need to add our ticket to
-	 * the list and we will do our own flushing further down.
-	 */
-	if (ret && flush != BTRFS_RESERVE_NO_FLUSH) {
-		ticket.orig_bytes = orig_bytes;
-		ticket.bytes = orig_bytes;
-		ticket.error = 0;
-		init_waitqueue_head(&ticket.wait);
-		if (flush == BTRFS_RESERVE_FLUSH_ALL) {
-			list_add_tail(&ticket.list, &space_info->tickets);
-			if (!space_info->flush) {
-				space_info->flush = 1;
-				trace_btrfs_trigger_flush(fs_info,
-							  space_info->flags,
-							  orig_bytes, flush,
-							  "enospc");
-				queue_work(system_unbound_wq,
-					   &fs_info->async_reclaim_work);
-			}
-		} else {
-			list_add_tail(&ticket.list,
-				      &space_info->priority_tickets);
-		}
-	} else if (!ret && space_info->flags & BTRFS_BLOCK_GROUP_METADATA) {
-		used += orig_bytes;
-		/*
-		 * We will do the space reservation dance during log replay,
-		 * which means we won't have fs_info->fs_root set, so don't do
-		 * the async reclaim as we will panic.
-		 */
-		if (!test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags) &&
-		    need_do_async_reclaim(fs_info, space_info,
-					  used, system_chunk) &&
-		    !work_busy(&fs_info->async_reclaim_work)) {
-			trace_btrfs_trigger_flush(fs_info, space_info->flags,
-						  orig_bytes, flush, "preempt");
-			queue_work(system_unbound_wq,
-				   &fs_info->async_reclaim_work);
-		}
-	}
-	spin_unlock(&space_info->lock);
-	if (!ret || flush == BTRFS_RESERVE_NO_FLUSH)
-		return ret;
-
-	if (flush == BTRFS_RESERVE_FLUSH_ALL)
-		return wait_reserve_ticket(fs_info, space_info, &ticket);
-
-	ret = 0;
-	priority_reclaim_metadata_space(fs_info, space_info, &ticket);
-	spin_lock(&space_info->lock);
-	if (ticket.bytes) {
-		if (ticket.bytes < orig_bytes)
-			reclaim_bytes = orig_bytes - ticket.bytes;
-		list_del_init(&ticket.list);
-		ret = -ENOSPC;
-	}
-	spin_unlock(&space_info->lock);
-
-	if (reclaim_bytes)
-		space_info_add_old_bytes(fs_info, space_info, reclaim_bytes);
-	ASSERT(list_empty(&ticket.list));
-	return ret;
-}
-
-/**
- * reserve_metadata_bytes - try to reserve bytes from the block_rsv's space
- * @root - the root we're allocating for
- * @block_rsv - the block_rsv we're allocating for
- * @orig_bytes - the number of bytes we want
- * @flush - whether or not we can flush to make our reservation
- *
- * This will reserve orig_bytes number of bytes from the space info associated
- * with the block_rsv.  If there is not enough space it will make an attempt to
- * flush out space to make room.  It will do this by flushing delalloc if
- * possible or committing the transaction.  If flush is 0 then no attempts to
- * regain reservations will be made and this will fail if there is not enough
- * space already.
- */
-static int reserve_metadata_bytes(struct btrfs_root *root,
-				  struct btrfs_block_rsv *block_rsv,
-				  u64 orig_bytes,
-				  enum btrfs_reserve_flush_enum flush)
-{
-	struct btrfs_fs_info *fs_info = root->fs_info;
-	struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
-	int ret;
-	bool system_chunk = (root == fs_info->chunk_root);
-
-	ret = __reserve_metadata_bytes(fs_info, block_rsv->space_info,
-				       orig_bytes, flush, system_chunk);
-	if (ret == -ENOSPC &&
-	    unlikely(root->orphan_cleanup_state == ORPHAN_CLEANUP_STARTED)) {
-		if (block_rsv != global_rsv &&
-		    !block_rsv_use_bytes(global_rsv, orig_bytes))
-			ret = 0;
-	}
-	if (ret == -ENOSPC) {
-		trace_btrfs_space_reservation(fs_info, "space_info:enospc",
-					      block_rsv->space_info->flags,
-					      orig_bytes, 1);
-
-		if (btrfs_test_opt(fs_info, ENOSPC_DEBUG))
-			dump_space_info(fs_info, block_rsv->space_info,
-					orig_bytes, 0);
-	}
-	return ret;
-}
-
-static struct btrfs_block_rsv *get_block_rsv(
-					const struct btrfs_trans_handle *trans,
-					const struct btrfs_root *root)
-{
-	struct btrfs_fs_info *fs_info = root->fs_info;
-	struct btrfs_block_rsv *block_rsv = NULL;
-
-	if (test_bit(BTRFS_ROOT_REF_COWS, &root->state) ||
-	    (root == fs_info->csum_root && trans->adding_csums) ||
-	    (root == fs_info->uuid_root))
-		block_rsv = trans->block_rsv;
-
-	if (!block_rsv)
-		block_rsv = root->block_rsv;
-
-	if (!block_rsv)
-		block_rsv = &fs_info->empty_block_rsv;
-
-	return block_rsv;
-}
-
-static int block_rsv_use_bytes(struct btrfs_block_rsv *block_rsv,
-			       u64 num_bytes)
-{
-	int ret = -ENOSPC;
-	spin_lock(&block_rsv->lock);
-	if (block_rsv->reserved >= num_bytes) {
-		block_rsv->reserved -= num_bytes;
-		if (block_rsv->reserved < block_rsv->size)
-			block_rsv->full = 0;
-		ret = 0;
-	}
-	spin_unlock(&block_rsv->lock);
-	return ret;
-}
-
-static void block_rsv_add_bytes(struct btrfs_block_rsv *block_rsv,
-				u64 num_bytes, bool update_size)
-{
-	spin_lock(&block_rsv->lock);
-	block_rsv->reserved += num_bytes;
-	if (update_size)
-		block_rsv->size += num_bytes;
-	else if (block_rsv->reserved >= block_rsv->size)
-		block_rsv->full = 1;
-	spin_unlock(&block_rsv->lock);
-}
-
-int btrfs_cond_migrate_bytes(struct btrfs_fs_info *fs_info,
-			     struct btrfs_block_rsv *dest, u64 num_bytes,
-			     int min_factor)
-{
-	struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
-	u64 min_bytes;
-
-	if (global_rsv->space_info != dest->space_info)
-		return -ENOSPC;
-
-	spin_lock(&global_rsv->lock);
-	min_bytes = div_factor(global_rsv->size, min_factor);
-	if (global_rsv->reserved < min_bytes + num_bytes) {
-		spin_unlock(&global_rsv->lock);
-		return -ENOSPC;
-	}
-	global_rsv->reserved -= num_bytes;
-	if (global_rsv->reserved < global_rsv->size)
-		global_rsv->full = 0;
-	spin_unlock(&global_rsv->lock);
-
-	block_rsv_add_bytes(dest, num_bytes, true);
-	return 0;
-}
-
-/**
- * btrfs_migrate_to_delayed_refs_rsv - transfer bytes to our delayed refs rsv.
- * @fs_info - the fs info for our fs.
- * @src - the source block rsv to transfer from.
- * @num_bytes - the number of bytes to transfer.
- *
- * This transfers up to the num_bytes amount from the src rsv to the
- * delayed_refs_rsv.  Any extra bytes are returned to the space info.
- */
-void btrfs_migrate_to_delayed_refs_rsv(struct btrfs_fs_info *fs_info,
-				       struct btrfs_block_rsv *src,
-				       u64 num_bytes)
-{
-	struct btrfs_block_rsv *delayed_refs_rsv = &fs_info->delayed_refs_rsv;
-	u64 to_free = 0;
-
-	spin_lock(&src->lock);
-	src->reserved -= num_bytes;
-	src->size -= num_bytes;
-	spin_unlock(&src->lock);
-
-	spin_lock(&delayed_refs_rsv->lock);
-	if (delayed_refs_rsv->size > delayed_refs_rsv->reserved) {
-		u64 delta = delayed_refs_rsv->size -
-			delayed_refs_rsv->reserved;
-		if (num_bytes > delta) {
-			to_free = num_bytes - delta;
-			num_bytes = delta;
-		}
-	} else {
-		to_free = num_bytes;
-		num_bytes = 0;
-	}
-
-	if (num_bytes)
-		delayed_refs_rsv->reserved += num_bytes;
-	if (delayed_refs_rsv->reserved >= delayed_refs_rsv->size)
-		delayed_refs_rsv->full = 1;
-	spin_unlock(&delayed_refs_rsv->lock);
-
-	if (num_bytes)
-		trace_btrfs_space_reservation(fs_info, "delayed_refs_rsv",
-					      0, num_bytes, 1);
-	if (to_free)
-		space_info_add_old_bytes(fs_info, delayed_refs_rsv->space_info,
-					 to_free);
-}
-
-/**
- * btrfs_delayed_refs_rsv_refill - refill based on our delayed refs usage.
- * @fs_info - the fs_info for our fs.
- * @flush - control how we can flush for this reservation.
- *
- * This will refill the delayed block_rsv up to 1 items size worth of space and
- * will return -ENOSPC if we can't make the reservation.
- */
-int btrfs_delayed_refs_rsv_refill(struct btrfs_fs_info *fs_info,
-				  enum btrfs_reserve_flush_enum flush)
-{
-	struct btrfs_block_rsv *block_rsv = &fs_info->delayed_refs_rsv;
-	u64 limit = btrfs_calc_trans_metadata_size(fs_info, 1);
-	u64 num_bytes = 0;
-	int ret = -ENOSPC;
-
-	spin_lock(&block_rsv->lock);
-	if (block_rsv->reserved < block_rsv->size) {
-		num_bytes = block_rsv->size - block_rsv->reserved;
-		num_bytes = min(num_bytes, limit);
-	}
-	spin_unlock(&block_rsv->lock);
-
-	if (!num_bytes)
-		return 0;
-
-	ret = reserve_metadata_bytes(fs_info->extent_root, block_rsv,
-				     num_bytes, flush);
-	if (ret)
-		return ret;
-	block_rsv_add_bytes(block_rsv, num_bytes, 0);
-	trace_btrfs_space_reservation(fs_info, "delayed_refs_rsv",
-				      0, num_bytes, 1);
-	return 0;
-}
-
-/*
- * This is for space we already have accounted in space_info->bytes_may_use, so
- * basically when we're returning space from block_rsv's.
- */
-static void space_info_add_old_bytes(struct btrfs_fs_info *fs_info,
-				     struct btrfs_space_info *space_info,
-				     u64 num_bytes)
-{
-	struct reserve_ticket *ticket;
-	struct list_head *head;
-	u64 used;
-	enum btrfs_reserve_flush_enum flush = BTRFS_RESERVE_NO_FLUSH;
-	bool check_overcommit = false;
-
-	spin_lock(&space_info->lock);
-	head = &space_info->priority_tickets;
-
-	/*
-	 * If we are over our limit then we need to check and see if we can
-	 * overcommit, and if we can't then we just need to free up our space
-	 * and not satisfy any requests.
-	 */
-	used = btrfs_space_info_used(space_info, true);
-	if (used - num_bytes >= space_info->total_bytes)
-		check_overcommit = true;
-again:
-	while (!list_empty(head) && num_bytes) {
-		ticket = list_first_entry(head, struct reserve_ticket,
-					  list);
-		/*
-		 * We use 0 bytes because this space is already reserved, so
-		 * adding the ticket space would be a double count.
-		 */
-		if (check_overcommit &&
-		    !can_overcommit(fs_info, space_info, 0, flush, false))
-			break;
-		if (num_bytes >= ticket->bytes) {
-			list_del_init(&ticket->list);
-			num_bytes -= ticket->bytes;
-			ticket->bytes = 0;
-			space_info->tickets_id++;
-			wake_up(&ticket->wait);
-		} else {
-			ticket->bytes -= num_bytes;
-			num_bytes = 0;
-		}
-	}
-
-	if (num_bytes && head == &space_info->priority_tickets) {
-		head = &space_info->tickets;
-		flush = BTRFS_RESERVE_FLUSH_ALL;
-		goto again;
-	}
-	update_bytes_may_use(space_info, -num_bytes);
-	trace_btrfs_space_reservation(fs_info, "space_info",
-				      space_info->flags, num_bytes, 0);
-	spin_unlock(&space_info->lock);
-}
-
-/*
- * This is for newly allocated space that isn't accounted in
- * space_info->bytes_may_use yet.  So if we allocate a chunk or unpin an extent
- * we use this helper.
- */
-static void space_info_add_new_bytes(struct btrfs_fs_info *fs_info,
-				     struct btrfs_space_info *space_info,
-				     u64 num_bytes)
-{
-	struct reserve_ticket *ticket;
-	struct list_head *head = &space_info->priority_tickets;
-
-again:
-	while (!list_empty(head) && num_bytes) {
-		ticket = list_first_entry(head, struct reserve_ticket,
-					  list);
-		if (num_bytes >= ticket->bytes) {
-			trace_btrfs_space_reservation(fs_info, "space_info",
-						      space_info->flags,
-						      ticket->bytes, 1);
-			list_del_init(&ticket->list);
-			num_bytes -= ticket->bytes;
-			update_bytes_may_use(space_info, ticket->bytes);
-			ticket->bytes = 0;
-			space_info->tickets_id++;
-			wake_up(&ticket->wait);
-		} else {
-			trace_btrfs_space_reservation(fs_info, "space_info",
-						      space_info->flags,
-						      num_bytes, 1);
-			update_bytes_may_use(space_info, num_bytes);
-			ticket->bytes -= num_bytes;
-			num_bytes = 0;
-		}
-	}
-
-	if (num_bytes && head == &space_info->priority_tickets) {
-		head = &space_info->tickets;
-		goto again;
-	}
-}
-
-static u64 block_rsv_release_bytes(struct btrfs_fs_info *fs_info,
-				    struct btrfs_block_rsv *block_rsv,
-				    struct btrfs_block_rsv *dest, u64 num_bytes,
-				    u64 *qgroup_to_release_ret)
-{
-	struct btrfs_space_info *space_info = block_rsv->space_info;
-	u64 qgroup_to_release = 0;
-	u64 ret;
-
-	spin_lock(&block_rsv->lock);
-	if (num_bytes == (u64)-1) {
-		num_bytes = block_rsv->size;
-		qgroup_to_release = block_rsv->qgroup_rsv_size;
-	}
-	block_rsv->size -= num_bytes;
-	if (block_rsv->reserved >= block_rsv->size) {
-		num_bytes = block_rsv->reserved - block_rsv->size;
-		block_rsv->reserved = block_rsv->size;
-		block_rsv->full = 1;
-	} else {
-		num_bytes = 0;
-	}
-	if (block_rsv->qgroup_rsv_reserved >= block_rsv->qgroup_rsv_size) {
-		qgroup_to_release = block_rsv->qgroup_rsv_reserved -
-				    block_rsv->qgroup_rsv_size;
-		block_rsv->qgroup_rsv_reserved = block_rsv->qgroup_rsv_size;
-	} else {
-		qgroup_to_release = 0;
-	}
-	spin_unlock(&block_rsv->lock);
-
-	ret = num_bytes;
-	if (num_bytes > 0) {
-		if (dest) {
-			spin_lock(&dest->lock);
-			if (!dest->full) {
-				u64 bytes_to_add;
-
-				bytes_to_add = dest->size - dest->reserved;
-				bytes_to_add = min(num_bytes, bytes_to_add);
-				dest->reserved += bytes_to_add;
-				if (dest->reserved >= dest->size)
-					dest->full = 1;
-				num_bytes -= bytes_to_add;
-			}
-			spin_unlock(&dest->lock);
-		}
-		if (num_bytes)
-			space_info_add_old_bytes(fs_info, space_info,
-						 num_bytes);
-	}
-	if (qgroup_to_release_ret)
-		*qgroup_to_release_ret = qgroup_to_release;
-	return ret;
-}
-
-int btrfs_block_rsv_migrate(struct btrfs_block_rsv *src,
-			    struct btrfs_block_rsv *dst, u64 num_bytes,
-			    bool update_size)
-{
-	int ret;
-
-	ret = block_rsv_use_bytes(src, num_bytes);
-	if (ret)
-		return ret;
-
-	block_rsv_add_bytes(dst, num_bytes, update_size);
-	return 0;
-}
-
-void btrfs_init_block_rsv(struct btrfs_block_rsv *rsv, unsigned short type)
-{
-	memset(rsv, 0, sizeof(*rsv));
-	spin_lock_init(&rsv->lock);
-	rsv->type = type;
-}
-
-void btrfs_init_metadata_block_rsv(struct btrfs_fs_info *fs_info,
-				   struct btrfs_block_rsv *rsv,
-				   unsigned short type)
-{
-	btrfs_init_block_rsv(rsv, type);
-	rsv->space_info = __find_space_info(fs_info,
-					    BTRFS_BLOCK_GROUP_METADATA);
-}
-
-struct btrfs_block_rsv *btrfs_alloc_block_rsv(struct btrfs_fs_info *fs_info,
-					      unsigned short type)
-{
-	struct btrfs_block_rsv *block_rsv;
-
-	block_rsv = kmalloc(sizeof(*block_rsv), GFP_NOFS);
-	if (!block_rsv)
-		return NULL;
-
-	btrfs_init_metadata_block_rsv(fs_info, block_rsv, type);
-	return block_rsv;
-}
-
-void btrfs_free_block_rsv(struct btrfs_fs_info *fs_info,
-			  struct btrfs_block_rsv *rsv)
-{
-	if (!rsv)
-		return;
-	btrfs_block_rsv_release(fs_info, rsv, (u64)-1);
-	kfree(rsv);
-}
-
-int btrfs_block_rsv_add(struct btrfs_root *root,
-			struct btrfs_block_rsv *block_rsv, u64 num_bytes,
-			enum btrfs_reserve_flush_enum flush)
-{
-	int ret;
-
-	if (num_bytes == 0)
-		return 0;
-
-	ret = reserve_metadata_bytes(root, block_rsv, num_bytes, flush);
-	if (!ret)
-		block_rsv_add_bytes(block_rsv, num_bytes, true);
-
-	return ret;
-}
-
-int btrfs_block_rsv_check(struct btrfs_block_rsv *block_rsv, int min_factor)
-{
-	u64 num_bytes = 0;
-	int ret = -ENOSPC;
-
-	if (!block_rsv)
-		return 0;
-
-	spin_lock(&block_rsv->lock);
-	num_bytes = div_factor(block_rsv->size, min_factor);
-	if (block_rsv->reserved >= num_bytes)
-		ret = 0;
-	spin_unlock(&block_rsv->lock);
-
-	return ret;
-}
-
-int btrfs_block_rsv_refill(struct btrfs_root *root,
-			   struct btrfs_block_rsv *block_rsv, u64 min_reserved,
-			   enum btrfs_reserve_flush_enum flush)
-{
-	u64 num_bytes = 0;
-	int ret = -ENOSPC;
-
-	if (!block_rsv)
-		return 0;
-
-	spin_lock(&block_rsv->lock);
-	num_bytes = min_reserved;
-	if (block_rsv->reserved >= num_bytes)
-		ret = 0;
-	else
-		num_bytes -= block_rsv->reserved;
-	spin_unlock(&block_rsv->lock);
-
-	if (!ret)
-		return 0;
-
-	ret = reserve_metadata_bytes(root, block_rsv, num_bytes, flush);
-	if (!ret) {
-		block_rsv_add_bytes(block_rsv, num_bytes, false);
-		return 0;
-	}
-
-	return ret;
-}
-
-static u64 __btrfs_block_rsv_release(struct btrfs_fs_info *fs_info,
-				     struct btrfs_block_rsv *block_rsv,
-				     u64 num_bytes, u64 *qgroup_to_release)
-{
-	struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
-	struct btrfs_block_rsv *delayed_rsv = &fs_info->delayed_refs_rsv;
-	struct btrfs_block_rsv *target = delayed_rsv;
-
-	if (target->full || target == block_rsv)
-		target = global_rsv;
-
-	if (block_rsv->space_info != target->space_info)
-		target = NULL;
-
-	return block_rsv_release_bytes(fs_info, block_rsv, target, num_bytes,
-				       qgroup_to_release);
-}
-
-void btrfs_block_rsv_release(struct btrfs_fs_info *fs_info,
-			     struct btrfs_block_rsv *block_rsv,
-			     u64 num_bytes)
-{
-	__btrfs_block_rsv_release(fs_info, block_rsv, num_bytes, NULL);
-}
-
-/**
- * btrfs_inode_rsv_release - release any excessive reservation.
- * @inode - the inode we need to release from.
- * @qgroup_free - free or convert qgroup meta.
- *   Unlike normal operation, qgroup meta reservation needs to know if we are
- *   freeing qgroup reservation or just converting it into per-trans.  Normally
- *   @qgroup_free is true for error handling, and false for normal release.
- *
- * This is the same as btrfs_block_rsv_release, except that it handles the
- * tracepoint for the reservation.
- */
-static void btrfs_inode_rsv_release(struct btrfs_inode *inode, bool qgroup_free)
-{
-	struct btrfs_fs_info *fs_info = inode->root->fs_info;
-	struct btrfs_block_rsv *block_rsv = &inode->block_rsv;
-	u64 released = 0;
-	u64 qgroup_to_release = 0;
-
-	/*
-	 * Since we statically set the block_rsv->size we just want to say we
-	 * are releasing 0 bytes, and then we'll just get the reservation over
-	 * the size free'd.
-	 */
-	released = __btrfs_block_rsv_release(fs_info, block_rsv, 0,
-					     &qgroup_to_release);
-	if (released > 0)
-		trace_btrfs_space_reservation(fs_info, "delalloc",
-					      btrfs_ino(inode), released, 0);
-	if (qgroup_free)
-		btrfs_qgroup_free_meta_prealloc(inode->root, qgroup_to_release);
-	else
-		btrfs_qgroup_convert_reserved_meta(inode->root,
-						   qgroup_to_release);
-}
-
-/**
- * btrfs_delayed_refs_rsv_release - release a ref head's reservation.
- * @fs_info - the fs_info for our fs.
- * @nr - the number of items to drop.
- *
- * This drops the delayed ref head's count from the delayed refs rsv and frees
- * any excess reservation we had.
- */
-void btrfs_delayed_refs_rsv_release(struct btrfs_fs_info *fs_info, int nr)
-{
-	struct btrfs_block_rsv *block_rsv = &fs_info->delayed_refs_rsv;
-	struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
-	u64 num_bytes = btrfs_calc_trans_metadata_size(fs_info, nr);
-	u64 released = 0;
-
-	released = block_rsv_release_bytes(fs_info, block_rsv, global_rsv,
-					   num_bytes, NULL);
-	if (released)
-		trace_btrfs_space_reservation(fs_info, "delayed_refs_rsv",
-					      0, released, 0);
-}
-
-static void update_global_block_rsv(struct btrfs_fs_info *fs_info)
-{
-	struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
-	struct btrfs_space_info *sinfo = block_rsv->space_info;
-	u64 num_bytes;
-
-	/*
-	 * The global block rsv is based on the size of the extent tree, the
-	 * checksum tree and the root tree.  If the fs is empty we want to set
-	 * it to a minimal amount for safety.
-	 */
-	num_bytes = btrfs_root_used(&fs_info->extent_root->root_item) +
-		btrfs_root_used(&fs_info->csum_root->root_item) +
-		btrfs_root_used(&fs_info->tree_root->root_item);
-	num_bytes = max_t(u64, num_bytes, SZ_16M);
-
-	spin_lock(&sinfo->lock);
-	spin_lock(&block_rsv->lock);
-
-	block_rsv->size = min_t(u64, num_bytes, SZ_512M);
-
-	if (block_rsv->reserved < block_rsv->size) {
-		num_bytes = btrfs_space_info_used(sinfo, true);
-		if (sinfo->total_bytes > num_bytes) {
-			num_bytes = sinfo->total_bytes - num_bytes;
-			num_bytes = min(num_bytes,
-					block_rsv->size - block_rsv->reserved);
-			block_rsv->reserved += num_bytes;
-			update_bytes_may_use(sinfo, num_bytes);
-			trace_btrfs_space_reservation(fs_info, "space_info",
-						      sinfo->flags, num_bytes,
-						      1);
-		}
-	} else if (block_rsv->reserved > block_rsv->size) {
-		num_bytes = block_rsv->reserved - block_rsv->size;
-		update_bytes_may_use(sinfo, -num_bytes);
-		trace_btrfs_space_reservation(fs_info, "space_info",
-				      sinfo->flags, num_bytes, 0);
-		block_rsv->reserved = block_rsv->size;
-	}
-
-	if (block_rsv->reserved == block_rsv->size)
-		block_rsv->full = 1;
-	else
-		block_rsv->full = 0;
-
-	spin_unlock(&block_rsv->lock);
-	spin_unlock(&sinfo->lock);
-}
-
-static void init_global_block_rsv(struct btrfs_fs_info *fs_info)
-{
-	struct btrfs_space_info *space_info;
-
-	space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
-	fs_info->chunk_block_rsv.space_info = space_info;
-
-	space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
-	fs_info->global_block_rsv.space_info = space_info;
-	fs_info->trans_block_rsv.space_info = space_info;
-	fs_info->empty_block_rsv.space_info = space_info;
-	fs_info->delayed_block_rsv.space_info = space_info;
-	fs_info->delayed_refs_rsv.space_info = space_info;
-
-	fs_info->extent_root->block_rsv = &fs_info->delayed_refs_rsv;
-	fs_info->csum_root->block_rsv = &fs_info->delayed_refs_rsv;
-	fs_info->dev_root->block_rsv = &fs_info->global_block_rsv;
-	fs_info->tree_root->block_rsv = &fs_info->global_block_rsv;
-	if (fs_info->quota_root)
-		fs_info->quota_root->block_rsv = &fs_info->global_block_rsv;
-	fs_info->chunk_root->block_rsv = &fs_info->chunk_block_rsv;
-
-	update_global_block_rsv(fs_info);
-}
-
-static void release_global_block_rsv(struct btrfs_fs_info *fs_info)
-{
-	block_rsv_release_bytes(fs_info, &fs_info->global_block_rsv, NULL,
-				(u64)-1, NULL);
-	WARN_ON(fs_info->trans_block_rsv.size > 0);
-	WARN_ON(fs_info->trans_block_rsv.reserved > 0);
-	WARN_ON(fs_info->chunk_block_rsv.size > 0);
-	WARN_ON(fs_info->chunk_block_rsv.reserved > 0);
-	WARN_ON(fs_info->delayed_block_rsv.size > 0);
-	WARN_ON(fs_info->delayed_block_rsv.reserved > 0);
-	WARN_ON(fs_info->delayed_refs_rsv.reserved > 0);
-	WARN_ON(fs_info->delayed_refs_rsv.size > 0);
-}
-
-/*
- * btrfs_update_delayed_refs_rsv - adjust the size of the delayed refs rsv
- * @trans - the trans that may have generated delayed refs
- *
- * This is to be called anytime we may have adjusted trans->delayed_ref_updates,
- * it'll calculate the additional size and add it to the delayed_refs_rsv.
- */
-void btrfs_update_delayed_refs_rsv(struct btrfs_trans_handle *trans)
-{
-	struct btrfs_fs_info *fs_info = trans->fs_info;
-	struct btrfs_block_rsv *delayed_rsv = &fs_info->delayed_refs_rsv;
-	u64 num_bytes;
-
-	if (!trans->delayed_ref_updates)
-		return;
-
-	num_bytes = btrfs_calc_trans_metadata_size(fs_info,
-						   trans->delayed_ref_updates);
-	spin_lock(&delayed_rsv->lock);
-	delayed_rsv->size += num_bytes;
-	delayed_rsv->full = 0;
-	spin_unlock(&delayed_rsv->lock);
-	trans->delayed_ref_updates = 0;
-}
-
-/*
- * To be called after all the new block groups attached to the transaction
- * handle have been created (btrfs_create_pending_block_groups()).
- */
-void btrfs_trans_release_chunk_metadata(struct btrfs_trans_handle *trans)
-{
-	struct btrfs_fs_info *fs_info = trans->fs_info;
-
-	if (!trans->chunk_bytes_reserved)
-		return;
-
-	WARN_ON_ONCE(!list_empty(&trans->new_bgs));
-
-	block_rsv_release_bytes(fs_info, &fs_info->chunk_block_rsv, NULL,
-				trans->chunk_bytes_reserved, NULL);
-	trans->chunk_bytes_reserved = 0;
-}
-
-/*
- * btrfs_subvolume_reserve_metadata() - reserve space for subvolume operation
- * root: the root of the parent directory
- * rsv: block reservation
- * items: the number of items that we need do reservation
- * use_global_rsv: allow fallback to the global block reservation
- *
- * This function is used to reserve the space for snapshot/subvolume
- * creation and deletion. Those operations are different with the
- * common file/directory operations, they change two fs/file trees
- * and root tree, the number of items that the qgroup reserves is
- * different with the free space reservation. So we can not use
- * the space reservation mechanism in start_transaction().
- */
-int btrfs_subvolume_reserve_metadata(struct btrfs_root *root,
-				     struct btrfs_block_rsv *rsv, int items,
-				     bool use_global_rsv)
-{
-	u64 qgroup_num_bytes = 0;
-	u64 num_bytes;
-	int ret;
-	struct btrfs_fs_info *fs_info = root->fs_info;
-	struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
-
-	if (test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags)) {
-		/* One for parent inode, two for dir entries */
-		qgroup_num_bytes = 3 * fs_info->nodesize;
-		ret = btrfs_qgroup_reserve_meta_prealloc(root,
-				qgroup_num_bytes, true);
-		if (ret)
-			return ret;
-	}
-
-	num_bytes = btrfs_calc_trans_metadata_size(fs_info, items);
-	rsv->space_info = __find_space_info(fs_info,
-					    BTRFS_BLOCK_GROUP_METADATA);
-	ret = btrfs_block_rsv_add(root, rsv, num_bytes,
-				  BTRFS_RESERVE_FLUSH_ALL);
-
-	if (ret == -ENOSPC && use_global_rsv)
-		ret = btrfs_block_rsv_migrate(global_rsv, rsv, num_bytes, true);
-
-	if (ret && qgroup_num_bytes)
-		btrfs_qgroup_free_meta_prealloc(root, qgroup_num_bytes);
-
-	return ret;
-}
-
-void btrfs_subvolume_release_metadata(struct btrfs_fs_info *fs_info,
-				      struct btrfs_block_rsv *rsv)
-{
-	btrfs_block_rsv_release(fs_info, rsv, (u64)-1);
-}
-
-static void btrfs_calculate_inode_block_rsv_size(struct btrfs_fs_info *fs_info,
-						 struct btrfs_inode *inode)
-{
-	struct btrfs_block_rsv *block_rsv = &inode->block_rsv;
-	u64 reserve_size = 0;
-	u64 qgroup_rsv_size = 0;
-	u64 csum_leaves;
-	unsigned outstanding_extents;
-
-	lockdep_assert_held(&inode->lock);
-	outstanding_extents = inode->outstanding_extents;
-	if (outstanding_extents)
-		reserve_size = btrfs_calc_trans_metadata_size(fs_info,
-						outstanding_extents + 1);
-	csum_leaves = btrfs_csum_bytes_to_leaves(fs_info,
-						 inode->csum_bytes);
-	reserve_size += btrfs_calc_trans_metadata_size(fs_info,
-						       csum_leaves);
-	/*
-	 * For qgroup rsv, the calculation is very simple:
-	 * account one nodesize for each outstanding extent
-	 *
-	 * This is overestimating in most cases.
-	 */
-	qgroup_rsv_size = (u64)outstanding_extents * fs_info->nodesize;
-
-	spin_lock(&block_rsv->lock);
-	block_rsv->size = reserve_size;
-	block_rsv->qgroup_rsv_size = qgroup_rsv_size;
-	spin_unlock(&block_rsv->lock);
-}
-
-static void calc_inode_reservations(struct btrfs_fs_info *fs_info,
-				    u64 num_bytes, u64 *meta_reserve,
-				    u64 *qgroup_reserve)
-{
-	u64 nr_extents = count_max_extents(num_bytes);
-	u64 csum_leaves = btrfs_csum_bytes_to_leaves(fs_info, num_bytes);
-
-	/* We add one for the inode update at finish ordered time */
-	*meta_reserve = btrfs_calc_trans_metadata_size(fs_info,
-						nr_extents + csum_leaves + 1);
-	*qgroup_reserve = nr_extents * fs_info->nodesize;
-}
-
-int btrfs_delalloc_reserve_metadata(struct btrfs_inode *inode, u64 num_bytes)
-{
-	struct btrfs_root *root = inode->root;
-	struct btrfs_fs_info *fs_info = root->fs_info;
-	struct btrfs_block_rsv *block_rsv = &inode->block_rsv;
-	u64 meta_reserve, qgroup_reserve;
-	unsigned nr_extents;
-	enum btrfs_reserve_flush_enum flush = BTRFS_RESERVE_FLUSH_ALL;
-	int ret = 0;
-	bool delalloc_lock = true;
-
-	/* If we are a free space inode we need to not flush since we will be in
-	 * the middle of a transaction commit.  We also don't need the delalloc
-	 * mutex since we won't race with anybody.  We need this mostly to make
-	 * lockdep shut its filthy mouth.
-	 *
-	 * If we have a transaction open (can happen if we call truncate_block
-	 * from truncate), then we need FLUSH_LIMIT so we don't deadlock.
-	 */
-	if (btrfs_is_free_space_inode(inode)) {
-		flush = BTRFS_RESERVE_NO_FLUSH;
-		delalloc_lock = false;
-	} else {
-		if (current->journal_info)
-			flush = BTRFS_RESERVE_FLUSH_LIMIT;
-
-		if (btrfs_transaction_in_commit(fs_info))
-			schedule_timeout(1);
-	}
-
-	if (delalloc_lock)
-		mutex_lock(&inode->delalloc_mutex);
-
-	num_bytes = ALIGN(num_bytes, fs_info->sectorsize);
-
-	/*
-	 * We always want to do it this way, every other way is wrong and ends
-	 * in tears.  Pre-reserving the amount we are going to add will always
-	 * be the right way, because otherwise if we have enough parallelism we
-	 * could end up with thousands of inodes all holding little bits of
-	 * reservations they were able to make previously and the only way to
-	 * reclaim that space is to ENOSPC out the operations and clear
-	 * everything out and try again, which is bad.  This way we just
-	 * over-reserve slightly, and clean up the mess when we are done.
-	 */
-	calc_inode_reservations(fs_info, num_bytes, &meta_reserve,
-				&qgroup_reserve);
-	ret = btrfs_qgroup_reserve_meta_prealloc(root, qgroup_reserve, true);
-	if (ret)
-		goto out_fail;
-	ret = reserve_metadata_bytes(root, block_rsv, meta_reserve, flush);
-	if (ret)
-		goto out_qgroup;
-
-	/*
-	 * Now we need to update our outstanding extents and csum bytes _first_
-	 * and then add the reservation to the block_rsv.  This keeps us from
-	 * racing with an ordered completion or some such that would think it
-	 * needs to free the reservation we just made.
-	 */
-	spin_lock(&inode->lock);
-	nr_extents = count_max_extents(num_bytes);
-	btrfs_mod_outstanding_extents(inode, nr_extents);
-	inode->csum_bytes += num_bytes;
-	btrfs_calculate_inode_block_rsv_size(fs_info, inode);
-	spin_unlock(&inode->lock);
-
-	/* Now we can safely add our space to our block rsv */
-	block_rsv_add_bytes(block_rsv, meta_reserve, false);
-	trace_btrfs_space_reservation(root->fs_info, "delalloc",
-				      btrfs_ino(inode), meta_reserve, 1);
-
-	spin_lock(&block_rsv->lock);
-	block_rsv->qgroup_rsv_reserved += qgroup_reserve;
-	spin_unlock(&block_rsv->lock);
-
-	if (delalloc_lock)
-		mutex_unlock(&inode->delalloc_mutex);
-	return 0;
-out_qgroup:
-	btrfs_qgroup_free_meta_prealloc(root, qgroup_reserve);
-out_fail:
-	btrfs_inode_rsv_release(inode, true);
-	if (delalloc_lock)
-		mutex_unlock(&inode->delalloc_mutex);
-	return ret;
-}
-
-/**
- * btrfs_delalloc_release_metadata - release a metadata reservation for an inode
- * @inode: the inode to release the reservation for.
- * @num_bytes: the number of bytes we are releasing.
- * @qgroup_free: free qgroup reservation or convert it to per-trans reservation
- *
- * This will release the metadata reservation for an inode.  This can be called
- * once we complete IO for a given set of bytes to release their metadata
- * reservations, or on error for the same reason.
- */
-void btrfs_delalloc_release_metadata(struct btrfs_inode *inode, u64 num_bytes,
-				     bool qgroup_free)
-{
-	struct btrfs_fs_info *fs_info = inode->root->fs_info;
-
-	num_bytes = ALIGN(num_bytes, fs_info->sectorsize);
-	spin_lock(&inode->lock);
-	inode->csum_bytes -= num_bytes;
-	btrfs_calculate_inode_block_rsv_size(fs_info, inode);
-	spin_unlock(&inode->lock);
-
-	if (btrfs_is_testing(fs_info))
-		return;
-
-	btrfs_inode_rsv_release(inode, qgroup_free);
-}
-
-/**
- * btrfs_delalloc_release_extents - release our outstanding_extents
- * @inode: the inode to balance the reservation for.
- * @num_bytes: the number of bytes we originally reserved with
- * @qgroup_free: do we need to free qgroup meta reservation or convert them.
- *
- * When we reserve space we increase outstanding_extents for the extents we may
- * add.  Once we've set the range as delalloc or created our ordered extents we
- * have outstanding_extents to track the real usage, so we use this to free our
- * temporarily tracked outstanding_extents.  This _must_ be used in conjunction
- * with btrfs_delalloc_reserve_metadata.
- */
-void btrfs_delalloc_release_extents(struct btrfs_inode *inode, u64 num_bytes,
-				    bool qgroup_free)
-{
-	struct btrfs_fs_info *fs_info = inode->root->fs_info;
-	unsigned num_extents;
-
-	spin_lock(&inode->lock);
-	num_extents = count_max_extents(num_bytes);
-	btrfs_mod_outstanding_extents(inode, -num_extents);
-	btrfs_calculate_inode_block_rsv_size(fs_info, inode);
-	spin_unlock(&inode->lock);
-
-	if (btrfs_is_testing(fs_info))
-		return;
-
-	btrfs_inode_rsv_release(inode, qgroup_free);
-}
-
-/**
- * btrfs_delalloc_reserve_space - reserve data and metadata space for
- * delalloc
- * @inode: inode we're writing to
- * @start: start range we are writing to
- * @len: how long the range we are writing to
- * @reserved: mandatory parameter, record actually reserved qgroup ranges of
- * 	      current reservation.
- *
- * This will do the following things
- *
- * o reserve space in data space info for num bytes
- *   and reserve precious corresponding qgroup space
- *   (Done in check_data_free_space)
- *
- * o reserve space for metadata space, based on the number of outstanding
- *   extents and how much csums will be needed
- *   also reserve metadata space in a per root over-reserve method.
- * o add to the inodes->delalloc_bytes
- * o add it to the fs_info's delalloc inodes list.
- *   (Above 3 all done in delalloc_reserve_metadata)
- *
- * Return 0 for success
- * Return <0 for error(-ENOSPC or -EQUOT)
- */
-int btrfs_delalloc_reserve_space(struct inode *inode,
-			struct extent_changeset **reserved, u64 start, u64 len)
-{
-	int ret;
-
-	ret = btrfs_check_data_free_space(inode, reserved, start, len);
-	if (ret < 0)
-		return ret;
-	ret = btrfs_delalloc_reserve_metadata(BTRFS_I(inode), len);
-	if (ret < 0)
-		btrfs_free_reserved_data_space(inode, *reserved, start, len);
-	return ret;
-}
-
-/**
- * btrfs_delalloc_release_space - release data and metadata space for delalloc
- * @inode: inode we're releasing space for
- * @start: start position of the space already reserved
- * @len: the len of the space already reserved
- * @release_bytes: the len of the space we consumed or didn't use
- *
- * This function will release the metadata space that was not used and will
- * decrement ->delalloc_bytes and remove it from the fs_info delalloc_inodes
- * list if there are no delalloc bytes left.
- * Also it will handle the qgroup reserved space.
- */
-void btrfs_delalloc_release_space(struct inode *inode,
-				  struct extent_changeset *reserved,
-				  u64 start, u64 len, bool qgroup_free)
-{
-	btrfs_delalloc_release_metadata(BTRFS_I(inode), len, qgroup_free);
-	btrfs_free_reserved_data_space(inode, reserved, start, len);
-}
-
 static int update_block_group(struct btrfs_trans_handle *trans,
 			      u64 bytenr, u64 num_bytes, int alloc)
 {
@@ -6296,7 +4168,8 @@ static int update_block_group(struct btrfs_trans_handle *trans,
 			old_val -= num_bytes;
 			btrfs_set_block_group_used(&cache->item, old_val);
 			cache->pinned += num_bytes;
-			update_bytes_pinned(cache->space_info, num_bytes);
+			btrfs_space_info_update_bytes_pinned(info,
+					cache->space_info, num_bytes);
 			cache->space_info->bytes_used -= num_bytes;
 			cache->space_info->disk_used -= num_bytes * factor;
 			spin_unlock(&cache->lock);
@@ -6371,7 +4244,8 @@ static int pin_down_extent(struct btrfs_block_group_cache *cache,
 	spin_lock(&cache->space_info->lock);
 	spin_lock(&cache->lock);
 	cache->pinned += num_bytes;
-	update_bytes_pinned(cache->space_info, num_bytes);
+	btrfs_space_info_update_bytes_pinned(fs_info, cache->space_info,
+					     num_bytes);
 	if (reserved) {
 		cache->reserved -= num_bytes;
 		cache->space_info->bytes_reserved -= num_bytes;
@@ -6580,7 +4454,8 @@ static int btrfs_add_reserved_bytes(struct btrfs_block_group_cache *cache,
 	} else {
 		cache->reserved += num_bytes;
 		space_info->bytes_reserved += num_bytes;
-		update_bytes_may_use(space_info, -ram_bytes);
+		btrfs_space_info_update_bytes_may_use(cache->fs_info,
+						      space_info, -ram_bytes);
 		if (delalloc)
 			cache->delalloc_bytes += num_bytes;
 	}
@@ -6646,7 +4521,7 @@ void btrfs_prepare_extent_commit(struct btrfs_fs_info *fs_info)
 
 	up_write(&fs_info->commit_root_sem);
 
-	update_global_block_rsv(fs_info);
+	btrfs_update_global_block_rsv(fs_info);
 }
 
 /*
@@ -6736,7 +4611,7 @@ static int unpin_extent_range(struct btrfs_fs_info *fs_info,
 		spin_lock(&space_info->lock);
 		spin_lock(&cache->lock);
 		cache->pinned -= len;
-		update_bytes_pinned(space_info, -len);
+		btrfs_space_info_update_bytes_pinned(fs_info, space_info, -len);
 
 		trace_btrfs_space_reservation(fs_info, "pinned",
 					      space_info->flags, len, 0);
@@ -6757,7 +4632,8 @@ static int unpin_extent_range(struct btrfs_fs_info *fs_info,
 				to_add = min(len, global_rsv->size -
 					     global_rsv->reserved);
 				global_rsv->reserved += to_add;
-				update_bytes_may_use(space_info, to_add);
+				btrfs_space_info_update_bytes_may_use(fs_info,
+						space_info, to_add);
 				if (global_rsv->reserved >= global_rsv->size)
 					global_rsv->full = 1;
 				trace_btrfs_space_reservation(fs_info,
@@ -6769,8 +4645,8 @@ static int unpin_extent_range(struct btrfs_fs_info *fs_info,
 			spin_unlock(&global_rsv->lock);
 			/* Add to any tickets we may have */
 			if (len)
-				space_info_add_new_bytes(fs_info, space_info,
-							 len);
+				btrfs_space_info_add_new_bytes(fs_info,
+						space_info, len);
 		}
 		spin_unlock(&space_info->lock);
 	}
@@ -7191,7 +5067,7 @@ void btrfs_free_tree_block(struct btrfs_trans_handle *trans,
 	}
 out:
 	if (pin)
-		add_pinned_bytes(fs_info, &generic_ref, 1);
+		add_pinned_bytes(fs_info, &generic_ref);
 
 	if (last_ref) {
 		/*
@@ -7239,7 +5115,7 @@ int btrfs_free_extent(struct btrfs_trans_handle *trans, struct btrfs_ref *ref)
 		btrfs_ref_tree_mod(fs_info, ref);
 
 	if (ret == 0 && old_ref_mod >= 0 && new_ref_mod < 0)
-		add_pinned_bytes(fs_info, ref, 1);
+		add_pinned_bytes(fs_info, ref);
 
 	return ret;
 }
@@ -7292,10 +5168,10 @@ wait_block_group_cache_done(struct btrfs_block_group_cache *cache)
 }
 
 enum btrfs_loop_type {
-	LOOP_CACHING_NOWAIT = 0,
-	LOOP_CACHING_WAIT = 1,
-	LOOP_ALLOC_CHUNK = 2,
-	LOOP_NO_EMPTY_SIZE = 3,
+	LOOP_CACHING_NOWAIT,
+	LOOP_CACHING_WAIT,
+	LOOP_ALLOC_CHUNK,
+	LOOP_NO_EMPTY_SIZE,
 };
 
 static inline void
@@ -7661,8 +5537,8 @@ static int find_free_extent_update_loop(struct btrfs_fs_info *fs_info,
 				return ret;
 			}
 
-			ret = do_chunk_alloc(trans, ffe_ctl->flags,
-					     CHUNK_ALLOC_FORCE);
+			ret = btrfs_chunk_alloc(trans, ffe_ctl->flags,
+						CHUNK_ALLOC_FORCE);
 
 			/*
 			 * If we can't allocate a new chunk we've already looped
@@ -7758,7 +5634,7 @@ static noinline int find_free_extent(struct btrfs_fs_info *fs_info,
 
 	trace_find_free_extent(fs_info, num_bytes, empty_size, flags);
 
-	space_info = __find_space_info(fs_info, flags);
+	space_info = btrfs_find_space_info(fs_info, flags);
 	if (!space_info) {
 		btrfs_err(fs_info, "No space info for %llu", flags);
 		return -ENOSPC;
@@ -7863,9 +5739,8 @@ search:
 		 */
 		if (!block_group_bits(block_group, flags)) {
 			u64 extra = BTRFS_BLOCK_GROUP_DUP |
-				BTRFS_BLOCK_GROUP_RAID1 |
-				BTRFS_BLOCK_GROUP_RAID5 |
-				BTRFS_BLOCK_GROUP_RAID6 |
+				BTRFS_BLOCK_GROUP_RAID1_MASK |
+				BTRFS_BLOCK_GROUP_RAID56_MASK |
 				BTRFS_BLOCK_GROUP_RAID10;
 
 			/*
@@ -7984,60 +5859,6 @@ loop:
 	return ret;
 }
 
-#define DUMP_BLOCK_RSV(fs_info, rsv_name)				\
-do {									\
-	struct btrfs_block_rsv *__rsv = &(fs_info)->rsv_name;		\
-	spin_lock(&__rsv->lock);					\
-	btrfs_info(fs_info, #rsv_name ": size %llu reserved %llu",	\
-		   __rsv->size, __rsv->reserved);			\
-	spin_unlock(&__rsv->lock);					\
-} while (0)
-
-static void dump_space_info(struct btrfs_fs_info *fs_info,
-			    struct btrfs_space_info *info, u64 bytes,
-			    int dump_block_groups)
-{
-	struct btrfs_block_group_cache *cache;
-	int index = 0;
-
-	spin_lock(&info->lock);
-	btrfs_info(fs_info, "space_info %llu has %llu free, is %sfull",
-		   info->flags,
-		   info->total_bytes - btrfs_space_info_used(info, true),
-		   info->full ? "" : "not ");
-	btrfs_info(fs_info,
-		"space_info total=%llu, used=%llu, pinned=%llu, reserved=%llu, may_use=%llu, readonly=%llu",
-		info->total_bytes, info->bytes_used, info->bytes_pinned,
-		info->bytes_reserved, info->bytes_may_use,
-		info->bytes_readonly);
-	spin_unlock(&info->lock);
-
-	DUMP_BLOCK_RSV(fs_info, global_block_rsv);
-	DUMP_BLOCK_RSV(fs_info, trans_block_rsv);
-	DUMP_BLOCK_RSV(fs_info, chunk_block_rsv);
-	DUMP_BLOCK_RSV(fs_info, delayed_block_rsv);
-	DUMP_BLOCK_RSV(fs_info, delayed_refs_rsv);
-
-	if (!dump_block_groups)
-		return;
-
-	down_read(&info->groups_sem);
-again:
-	list_for_each_entry(cache, &info->block_groups[index], list) {
-		spin_lock(&cache->lock);
-		btrfs_info(fs_info,
-			"block group %llu has %llu bytes, %llu used %llu pinned %llu reserved %s",
-			cache->key.objectid, cache->key.offset,
-			btrfs_block_group_used(&cache->item), cache->pinned,
-			cache->reserved, cache->ro ? "[readonly]" : "");
-		btrfs_dump_free_space(cache, bytes);
-		spin_unlock(&cache->lock);
-	}
-	if (++index < BTRFS_NR_RAID_TYPES)
-		goto again;
-	up_read(&info->groups_sem);
-}
-
 /*
  * btrfs_reserve_extent - entry point to the extent allocator. Tries to find a
  *			  hole that is at least as big as @num_bytes.
@@ -8113,12 +5934,13 @@ again:
 		} else if (btrfs_test_opt(fs_info, ENOSPC_DEBUG)) {
 			struct btrfs_space_info *sinfo;
 
-			sinfo = __find_space_info(fs_info, flags);
+			sinfo = btrfs_find_space_info(fs_info, flags);
 			btrfs_err(fs_info,
 				  "allocation failed flags %llu, wanted %llu",
 				  flags, num_bytes);
 			if (sinfo)
-				dump_space_info(fs_info, sinfo, num_bytes, 1);
+				btrfs_dump_space_info(fs_info, sinfo,
+						      num_bytes, 1);
 		}
 	}
 
@@ -8456,73 +6278,6 @@ btrfs_init_new_buffer(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 	return buf;
 }
 
-static struct btrfs_block_rsv *
-use_block_rsv(struct btrfs_trans_handle *trans,
-	      struct btrfs_root *root, u32 blocksize)
-{
-	struct btrfs_fs_info *fs_info = root->fs_info;
-	struct btrfs_block_rsv *block_rsv;
-	struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
-	int ret;
-	bool global_updated = false;
-
-	block_rsv = get_block_rsv(trans, root);
-
-	if (unlikely(block_rsv->size == 0))
-		goto try_reserve;
-again:
-	ret = block_rsv_use_bytes(block_rsv, blocksize);
-	if (!ret)
-		return block_rsv;
-
-	if (block_rsv->failfast)
-		return ERR_PTR(ret);
-
-	if (block_rsv->type == BTRFS_BLOCK_RSV_GLOBAL && !global_updated) {
-		global_updated = true;
-		update_global_block_rsv(fs_info);
-		goto again;
-	}
-
-	/*
-	 * The global reserve still exists to save us from ourselves, so don't
-	 * warn_on if we are short on our delayed refs reserve.
-	 */
-	if (block_rsv->type != BTRFS_BLOCK_RSV_DELREFS &&
-	    btrfs_test_opt(fs_info, ENOSPC_DEBUG)) {
-		static DEFINE_RATELIMIT_STATE(_rs,
-				DEFAULT_RATELIMIT_INTERVAL * 10,
-				/*DEFAULT_RATELIMIT_BURST*/ 1);
-		if (__ratelimit(&_rs))
-			WARN(1, KERN_DEBUG
-				"BTRFS: block rsv returned %d\n", ret);
-	}
-try_reserve:
-	ret = reserve_metadata_bytes(root, block_rsv, blocksize,
-				     BTRFS_RESERVE_NO_FLUSH);
-	if (!ret)
-		return block_rsv;
-	/*
-	 * If we couldn't reserve metadata bytes try and use some from
-	 * the global reserve if its space type is the same as the global
-	 * reservation.
-	 */
-	if (block_rsv->type != BTRFS_BLOCK_RSV_GLOBAL &&
-	    block_rsv->space_info == global_rsv->space_info) {
-		ret = block_rsv_use_bytes(global_rsv, blocksize);
-		if (!ret)
-			return global_rsv;
-	}
-	return ERR_PTR(ret);
-}
-
-static void unuse_block_rsv(struct btrfs_fs_info *fs_info,
-			    struct btrfs_block_rsv *block_rsv, u32 blocksize)
-{
-	block_rsv_add_bytes(block_rsv, blocksize, false);
-	block_rsv_release_bytes(fs_info, block_rsv, NULL, 0, NULL);
-}
-
 /*
  * finds a free extent and does all the dirty work required for allocation
  * returns the tree buffer or an ERR_PTR on error.
@@ -8555,7 +6310,7 @@ struct extent_buffer *btrfs_alloc_tree_block(struct btrfs_trans_handle *trans,
 	}
 #endif
 
-	block_rsv = use_block_rsv(trans, root, blocksize);
+	block_rsv = btrfs_use_block_rsv(trans, root, blocksize);
 	if (IS_ERR(block_rsv))
 		return ERR_CAST(block_rsv);
 
@@ -8613,7 +6368,7 @@ out_free_buf:
 out_free_reserved:
 	btrfs_free_reserved_extent(fs_info, ins.objectid, ins.offset, 0);
 out_unuse:
-	unuse_block_rsv(fs_info, block_rsv, blocksize);
+	btrfs_unuse_block_rsv(fs_info, block_rsv, blocksize);
 	return ERR_PTR(ret);
 }
 
@@ -9552,9 +7307,8 @@ static u64 update_block_group_flags(struct btrfs_fs_info *fs_info, u64 flags)
 
 	num_devices = fs_info->fs_devices->rw_devices;
 
-	stripped = BTRFS_BLOCK_GROUP_RAID0 |
-		BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6 |
-		BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10;
+	stripped = BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID56_MASK |
+		BTRFS_BLOCK_GROUP_RAID1_MASK | BTRFS_BLOCK_GROUP_RAID10;
 
 	if (num_devices == 1) {
 		stripped |= BTRFS_BLOCK_GROUP_DUP;
@@ -9565,7 +7319,7 @@ static u64 update_block_group_flags(struct btrfs_fs_info *fs_info, u64 flags)
 			return stripped;
 
 		/* turn mirroring into duplication */
-		if (flags & (BTRFS_BLOCK_GROUP_RAID1 |
+		if (flags & (BTRFS_BLOCK_GROUP_RAID1_MASK |
 			     BTRFS_BLOCK_GROUP_RAID10))
 			return stripped | BTRFS_BLOCK_GROUP_DUP;
 	} else {
@@ -9636,7 +7390,7 @@ out:
 		btrfs_info(cache->fs_info,
 			"sinfo_used=%llu bg_num_bytes=%llu min_allocable=%llu",
 			sinfo_used, num_bytes, min_allocable_bytes);
-		dump_space_info(cache->fs_info, cache->space_info, 0, 0);
+		btrfs_dump_space_info(cache->fs_info, cache->space_info, 0, 0);
 	}
 	return ret;
 }
@@ -9678,8 +7432,7 @@ again:
 	 */
 	alloc_flags = update_block_group_flags(fs_info, cache->flags);
 	if (alloc_flags != cache->flags) {
-		ret = do_chunk_alloc(trans, alloc_flags,
-				     CHUNK_ALLOC_FORCE);
+		ret = btrfs_chunk_alloc(trans, alloc_flags, CHUNK_ALLOC_FORCE);
 		/*
 		 * ENOSPC is allowed here, we may have enough space
 		 * already allocated at the new raid level to
@@ -9695,7 +7448,7 @@ again:
 	if (!ret)
 		goto out;
 	alloc_flags = get_alloc_profile(fs_info, cache->space_info->flags);
-	ret = do_chunk_alloc(trans, alloc_flags, CHUNK_ALLOC_FORCE);
+	ret = btrfs_chunk_alloc(trans, alloc_flags, CHUNK_ALLOC_FORCE);
 	if (ret < 0)
 		goto out;
 	ret = inc_block_group_ro(cache, 0);
@@ -9716,7 +7469,7 @@ int btrfs_force_chunk_alloc(struct btrfs_trans_handle *trans, u64 type)
 {
 	u64 alloc_flags = get_alloc_profile(trans->fs_info, type);
 
-	return do_chunk_alloc(trans, alloc_flags, CHUNK_ALLOC_FORCE);
+	return btrfs_chunk_alloc(trans, alloc_flags, CHUNK_ALLOC_FORCE);
 }
 
 /*
@@ -9949,7 +7702,7 @@ static int find_first_block_group(struct btrfs_fs_info *fs_info,
 			struct extent_map_tree *em_tree;
 			struct extent_map *em;
 
-			em_tree = &root->fs_info->mapping_tree.map_tree;
+			em_tree = &root->fs_info->mapping_tree;
 			read_lock(&em_tree->lock);
 			em = lookup_extent_mapping(em_tree, found_key.objectid,
 						   found_key.offset);
@@ -10102,7 +7855,7 @@ int btrfs_free_block_groups(struct btrfs_fs_info *info)
 	 */
 	synchronize_rcu();
 
-	release_global_block_rsv(info);
+	btrfs_release_global_block_rsv(info);
 
 	while (!list_empty(&info->space_info)) {
 		int i;
@@ -10118,7 +7871,7 @@ int btrfs_free_block_groups(struct btrfs_fs_info *info)
 		if (WARN_ON(space_info->bytes_pinned > 0 ||
 			    space_info->bytes_reserved > 0 ||
 			    space_info->bytes_may_use > 0))
-			dump_space_info(info, space_info, 0, 0);
+			btrfs_dump_space_info(info, space_info, 0, 0);
 		list_del(&space_info->list);
 		for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) {
 			struct kobject *kobj;
@@ -10141,7 +7894,6 @@ void btrfs_add_raid_kobjects(struct btrfs_fs_info *fs_info)
 	struct btrfs_space_info *space_info;
 	struct raid_kobject *rkobj;
 	LIST_HEAD(list);
-	int index;
 	int ret = 0;
 
 	spin_lock(&fs_info->pending_raid_kobjs_lock);
@@ -10149,11 +7901,10 @@ void btrfs_add_raid_kobjects(struct btrfs_fs_info *fs_info)
 	spin_unlock(&fs_info->pending_raid_kobjs_lock);
 
 	list_for_each_entry(rkobj, &list, list) {
-		space_info = __find_space_info(fs_info, rkobj->flags);
-		index = btrfs_bg_flags_to_raid_index(rkobj->flags);
+		space_info = btrfs_find_space_info(fs_info, rkobj->flags);
 
 		ret = kobject_add(&rkobj->kobj, &space_info->kobj,
-				  "%s", get_raid_name(index));
+				"%s", btrfs_bg_type_to_raid_name(rkobj->flags));
 		if (ret) {
 			kobject_put(&rkobj->kobj);
 			break;
@@ -10243,21 +7994,21 @@ btrfs_create_block_group_cache(struct btrfs_fs_info *fs_info,
  */
 static int check_chunk_block_group_mappings(struct btrfs_fs_info *fs_info)
 {
-	struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree;
+	struct extent_map_tree *map_tree = &fs_info->mapping_tree;
 	struct extent_map *em;
 	struct btrfs_block_group_cache *bg;
 	u64 start = 0;
 	int ret = 0;
 
 	while (1) {
-		read_lock(&map_tree->map_tree.lock);
+		read_lock(&map_tree->lock);
 		/*
 		 * lookup_extent_mapping will return the first extent map
 		 * intersecting the range, so setting @len to 1 is enough to
 		 * get the first chunk.
 		 */
-		em = lookup_extent_mapping(&map_tree->map_tree, start, 1);
-		read_unlock(&map_tree->map_tree.lock);
+		em = lookup_extent_mapping(map_tree, start, 1);
+		read_unlock(&map_tree->lock);
 		if (!em)
 			break;
 
@@ -10417,9 +8168,9 @@ int btrfs_read_block_groups(struct btrfs_fs_info *info)
 		}
 
 		trace_btrfs_add_block_group(info, cache, 0);
-		update_space_info(info, cache->flags, found_key.offset,
-				  btrfs_block_group_used(&cache->item),
-				  cache->bytes_super, &space_info);
+		btrfs_update_space_info(info, cache->flags, found_key.offset,
+					btrfs_block_group_used(&cache->item),
+					cache->bytes_super, &space_info);
 
 		cache->space_info = space_info;
 
@@ -10437,9 +8188,8 @@ int btrfs_read_block_groups(struct btrfs_fs_info *info)
 	list_for_each_entry_rcu(space_info, &info->space_info, list) {
 		if (!(get_alloc_profile(info, space_info->flags) &
 		      (BTRFS_BLOCK_GROUP_RAID10 |
-		       BTRFS_BLOCK_GROUP_RAID1 |
-		       BTRFS_BLOCK_GROUP_RAID5 |
-		       BTRFS_BLOCK_GROUP_RAID6 |
+		       BTRFS_BLOCK_GROUP_RAID1_MASK |
+		       BTRFS_BLOCK_GROUP_RAID56_MASK |
 		       BTRFS_BLOCK_GROUP_DUP)))
 			continue;
 		/*
@@ -10457,7 +8207,7 @@ int btrfs_read_block_groups(struct btrfs_fs_info *info)
 	}
 
 	btrfs_add_raid_kobjects(info);
-	init_global_block_rsv(info);
+	btrfs_init_global_block_rsv(info);
 	ret = check_chunk_block_group_mappings(info);
 error:
 	btrfs_free_path(path);
@@ -10554,7 +8304,7 @@ int btrfs_make_block_group(struct btrfs_trans_handle *trans, u64 bytes_used,
 	 * assigned to our block group. We want our bg to be added to the rbtree
 	 * with its ->space_info set.
 	 */
-	cache->space_info = __find_space_info(fs_info, cache->flags);
+	cache->space_info = btrfs_find_space_info(fs_info, cache->flags);
 	ASSERT(cache->space_info);
 
 	ret = btrfs_add_block_group_cache(fs_info, cache);
@@ -10569,9 +8319,9 @@ int btrfs_make_block_group(struct btrfs_trans_handle *trans, u64 bytes_used,
 	 * the rbtree, update the space info's counters.
 	 */
 	trace_btrfs_add_block_group(fs_info, cache, 1);
-	update_space_info(fs_info, cache->flags, size, bytes_used,
+	btrfs_update_space_info(fs_info, cache->flags, size, bytes_used,
 				cache->bytes_super, &cache->space_info);
-	update_global_block_rsv(fs_info);
+	btrfs_update_global_block_rsv(fs_info);
 
 	link_block_group(cache);
 
@@ -10598,6 +8348,35 @@ static void clear_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
 	write_sequnlock(&fs_info->profiles_lock);
 }
 
+/*
+ * Clear incompat bits for the following feature(s):
+ *
+ * - RAID56 - in case there's neither RAID5 nor RAID6 profile block group
+ *            in the whole filesystem
+ */
+static void clear_incompat_bg_bits(struct btrfs_fs_info *fs_info, u64 flags)
+{
+	if (flags & BTRFS_BLOCK_GROUP_RAID56_MASK) {
+		struct list_head *head = &fs_info->space_info;
+		struct btrfs_space_info *sinfo;
+
+		list_for_each_entry_rcu(sinfo, head, list) {
+			bool found = false;
+
+			down_read(&sinfo->groups_sem);
+			if (!list_empty(&sinfo->block_groups[BTRFS_RAID_RAID5]))
+				found = true;
+			if (!list_empty(&sinfo->block_groups[BTRFS_RAID_RAID6]))
+				found = true;
+			up_read(&sinfo->groups_sem);
+
+			if (found)
+				return;
+		}
+		btrfs_clear_fs_incompat(fs_info, RAID56);
+	}
+}
+
 int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
 			     u64 group_start, struct extent_map *em)
 {
@@ -10744,6 +8523,7 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
 		clear_avail_alloc_bits(fs_info, block_group->flags);
 	}
 	up_write(&block_group->space_info->groups_sem);
+	clear_incompat_bg_bits(fs_info, block_group->flags);
 	if (kobj) {
 		kobject_del(kobj);
 		kobject_put(kobj);
@@ -10853,7 +8633,7 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
 	if (remove_em) {
 		struct extent_map_tree *em_tree;
 
-		em_tree = &fs_info->mapping_tree.map_tree;
+		em_tree = &fs_info->mapping_tree;
 		write_lock(&em_tree->lock);
 		remove_extent_mapping(em_tree, em);
 		write_unlock(&em_tree->lock);
@@ -10871,7 +8651,7 @@ struct btrfs_trans_handle *
 btrfs_start_trans_remove_block_group(struct btrfs_fs_info *fs_info,
 				     const u64 chunk_offset)
 {
-	struct extent_map_tree *em_tree = &fs_info->mapping_tree.map_tree;
+	struct extent_map_tree *em_tree = &fs_info->mapping_tree;
 	struct extent_map *em;
 	struct map_lookup *map;
 	unsigned int num_items;
@@ -11020,7 +8800,8 @@ void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info)
 		spin_lock(&space_info->lock);
 		spin_lock(&block_group->lock);
 
-		update_bytes_pinned(space_info, -block_group->pinned);
+		btrfs_space_info_update_bytes_pinned(fs_info, space_info,
+						     -block_group->pinned);
 		space_info->bytes_readonly += block_group->pinned;
 		percpu_counter_add_batch(&space_info->total_bytes_pinned,
 				   -block_group->pinned,
@@ -11076,43 +8857,6 @@ next:
 	spin_unlock(&fs_info->unused_bgs_lock);
 }
 
-int btrfs_init_space_info(struct btrfs_fs_info *fs_info)
-{
-	struct btrfs_super_block *disk_super;
-	u64 features;
-	u64 flags;
-	int mixed = 0;
-	int ret;
-
-	disk_super = fs_info->super_copy;
-	if (!btrfs_super_root(disk_super))
-		return -EINVAL;
-
-	features = btrfs_super_incompat_flags(disk_super);
-	if (features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)
-		mixed = 1;
-
-	flags = BTRFS_BLOCK_GROUP_SYSTEM;
-	ret = create_space_info(fs_info, flags);
-	if (ret)
-		goto out;
-
-	if (mixed) {
-		flags = BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA;
-		ret = create_space_info(fs_info, flags);
-	} else {
-		flags = BTRFS_BLOCK_GROUP_METADATA;
-		ret = create_space_info(fs_info, flags);
-		if (ret)
-			goto out;
-
-		flags = BTRFS_BLOCK_GROUP_DATA;
-		ret = create_space_info(fs_info, flags);
-	}
-out:
-	return ret;
-}
-
 int btrfs_error_unpin_extent_range(struct btrfs_fs_info *fs_info,
 				   u64 start, u64 end)
 {
@@ -11171,12 +8915,17 @@ static int btrfs_trim_free_extents(struct btrfs_device *device, u64 *trimmed)
 		find_first_clear_extent_bit(&device->alloc_state, start,
 					    &start, &end,
 					    CHUNK_TRIMMED | CHUNK_ALLOCATED);
+
+		/* Ensure we skip the reserved area in the first 1M */
+		start = max_t(u64, start, SZ_1M);
+
 		/*
 		 * If find_first_clear_extent_bit find a range that spans the
 		 * end of the device it will set end to -1, in this case it's up
 		 * to the caller to trim the value to the size of the device.
 		 */
 		end = min(end, device->total_bytes - 1);
+
 		len = end - start + 1;
 
 		/* We didn't find any extents */
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 5106008f5e28..1ff438fd5bc2 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -359,6 +359,24 @@ do_insert:
 	return NULL;
 }
 
+/**
+ * __etree_search - searche @tree for an entry that contains @offset. Such
+ * entry would have entry->start <= offset && entry->end >= offset.
+ *
+ * @tree - the tree to search
+ * @offset - offset that should fall within an entry in @tree
+ * @next_ret - pointer to the first entry whose range ends after @offset
+ * @prev - pointer to the first entry whose range begins before @offset
+ * @p_ret - pointer where new node should be anchored (used when inserting an
+ *	    entry in the tree)
+ * @parent_ret - points to entry which would have been the parent of the entry,
+ *               containing @offset
+ *
+ * This function returns a pointer to the entry that contains @offset byte
+ * address. If no such entry exists, then NULL is returned and the other
+ * pointer arguments to the function are filled, otherwise the found entry is
+ * returned and other pointers are left untouched.
+ */
 static struct rb_node *__etree_search(struct extent_io_tree *tree, u64 offset,
 				      struct rb_node **next_ret,
 				      struct rb_node **prev_ret,
@@ -504,9 +522,11 @@ static int insert_state(struct extent_io_tree *tree,
 {
 	struct rb_node *node;
 
-	if (end < start)
-		WARN(1, KERN_ERR "BTRFS: end < start %llu %llu\n",
-		       end, start);
+	if (end < start) {
+		btrfs_err(tree->fs_info,
+			"insert state: end < start %llu %llu", end, start);
+		WARN_ON(1);
+	}
 	state->start = start;
 	state->end = end;
 
@@ -516,7 +536,8 @@ static int insert_state(struct extent_io_tree *tree,
 	if (node) {
 		struct extent_state *found;
 		found = rb_entry(node, struct extent_state, rb_node);
-		pr_err("BTRFS: found node %llu %llu on insert of %llu %llu\n",
+		btrfs_err(tree->fs_info,
+		       "found node %llu %llu on insert of %llu %llu",
 		       found->start, found->end, start, end);
 		return -EEXIST;
 	}
@@ -1537,8 +1558,8 @@ out:
 }
 
 /**
- * find_first_clear_extent_bit - finds the first range that has @bits not set
- * and that starts after @start
+ * find_first_clear_extent_bit - find the first range that has @bits not set.
+ * This range could start before @start.
  *
  * @tree - the tree to search
  * @start - the offset at/after which the found extent should start
@@ -1578,12 +1599,52 @@ void find_first_clear_extent_bit(struct extent_io_tree *tree, u64 start,
 				goto out;
 			}
 		}
+		/*
+		 * At this point 'node' either contains 'start' or start is
+		 * before 'node'
+		 */
 		state = rb_entry(node, struct extent_state, rb_node);
-		if (in_range(start, state->start, state->end - state->start + 1) &&
-			(state->state & bits)) {
-			start = state->end + 1;
+
+		if (in_range(start, state->start, state->end - state->start + 1)) {
+			if (state->state & bits) {
+				/*
+				 * |--range with bits sets--|
+				 *    |
+				 *    start
+				 */
+				start = state->end + 1;
+			} else {
+				/*
+				 * 'start' falls within a range that doesn't
+				 * have the bits set, so take its start as
+				 * the beginning of the desired range
+				 *
+				 * |--range with bits cleared----|
+				 *      |
+				 *      start
+				 */
+				*start_ret = state->start;
+				break;
+			}
 		} else {
-			*start_ret = start;
+			/*
+			 * |---prev range---|---hole/unset---|---node range---|
+			 *                          |
+			 *                        start
+			 *
+			 *                        or
+			 *
+			 * |---hole/unset--||--first node--|
+			 * 0   |
+			 *    start
+			 */
+			if (prev) {
+				state = rb_entry(prev, struct extent_state,
+						 rb_node);
+				*start_ret = state->end + 1;
+			} else {
+				*start_ret = 0;
+			}
 			break;
 		}
 	}
@@ -1719,10 +1780,10 @@ static noinline int lock_delalloc_pages(struct inode *inode,
  */
 EXPORT_FOR_TESTS
 noinline_for_stack bool find_lock_delalloc_range(struct inode *inode,
-				    struct extent_io_tree *tree,
 				    struct page *locked_page, u64 *start,
 				    u64 *end)
 {
+	struct extent_io_tree *tree = &BTRFS_I(inode)->io_tree;
 	u64 max_bytes = BTRFS_MAX_EXTENT_SIZE;
 	u64 delalloc_start;
 	u64 delalloc_end;
@@ -2800,12 +2861,11 @@ static inline void btrfs_io_bio_init(struct btrfs_io_bio *btrfs_bio)
  * never fail.  We're returning a bio right now but you can call btrfs_io_bio
  * for the appropriate container_of magic
  */
-struct bio *btrfs_bio_alloc(struct block_device *bdev, u64 first_byte)
+struct bio *btrfs_bio_alloc(u64 first_byte)
 {
 	struct bio *bio;
 
 	bio = bio_alloc_bioset(GFP_NOFS, BIO_MAX_PAGES, &btrfs_bioset);
-	bio_set_dev(bio, bdev);
 	bio->bi_iter.bi_sector = first_byte >> 9;
 	btrfs_io_bio_init(btrfs_io_bio(bio));
 	return bio;
@@ -2916,7 +2976,8 @@ static int submit_extent_page(unsigned int opf, struct extent_io_tree *tree,
 		}
 	}
 
-	bio = btrfs_bio_alloc(bdev, offset);
+	bio = btrfs_bio_alloc(offset);
+	bio_set_dev(bio, bdev);
 	bio_add_page(bio, page, page_size, pg_offset);
 	bio->bi_end_io = end_io_func;
 	bio->bi_private = tree;
@@ -3204,21 +3265,10 @@ static inline void contiguous_readpages(struct extent_io_tree *tree,
 					     unsigned long *bio_flags,
 					     u64 *prev_em_start)
 {
-	struct inode *inode;
-	struct btrfs_ordered_extent *ordered;
+	struct btrfs_inode *inode = BTRFS_I(pages[0]->mapping->host);
 	int index;
 
-	inode = pages[0]->mapping->host;
-	while (1) {
-		lock_extent(tree, start, end);
-		ordered = btrfs_lookup_ordered_range(BTRFS_I(inode), start,
-						     end - start + 1);
-		if (!ordered)
-			break;
-		unlock_extent(tree, start, end);
-		btrfs_start_ordered_extent(inode, ordered, 1);
-		btrfs_put_ordered_extent(ordered);
-	}
+	btrfs_lock_and_flush_ordered_range(tree, inode, start, end, NULL);
 
 	for (index = 0; index < nr_pages; index++) {
 		__do_readpage(tree, pages[index], btrfs_get_extent, em_cached,
@@ -3234,22 +3284,12 @@ static int __extent_read_full_page(struct extent_io_tree *tree,
 				   unsigned long *bio_flags,
 				   unsigned int read_flags)
 {
-	struct inode *inode = page->mapping->host;
-	struct btrfs_ordered_extent *ordered;
+	struct btrfs_inode *inode = BTRFS_I(page->mapping->host);
 	u64 start = page_offset(page);
 	u64 end = start + PAGE_SIZE - 1;
 	int ret;
 
-	while (1) {
-		lock_extent(tree, start, end);
-		ordered = btrfs_lookup_ordered_range(BTRFS_I(inode), start,
-						PAGE_SIZE);
-		if (!ordered)
-			break;
-		unlock_extent(tree, start, end);
-		btrfs_start_ordered_extent(inode, ordered, 1);
-		btrfs_put_ordered_extent(ordered);
-	}
+	btrfs_lock_and_flush_ordered_range(tree, inode, start, end, NULL);
 
 	ret = __do_readpage(tree, page, get_extent, NULL, bio, mirror_num,
 			    bio_flags, read_flags, NULL);
@@ -3290,7 +3330,6 @@ static noinline_for_stack int writepage_delalloc(struct inode *inode,
 		struct page *page, struct writeback_control *wbc,
 		u64 delalloc_start, unsigned long *nr_written)
 {
-	struct extent_io_tree *tree = &BTRFS_I(inode)->io_tree;
 	u64 page_end = delalloc_start + PAGE_SIZE - 1;
 	bool found;
 	u64 delalloc_to_write = 0;
@@ -3300,8 +3339,7 @@ static noinline_for_stack int writepage_delalloc(struct inode *inode,
 
 
 	while (delalloc_end < page_end) {
-		found = find_lock_delalloc_range(inode, tree,
-					       page,
+		found = find_lock_delalloc_range(inode, page,
 					       &delalloc_start,
 					       &delalloc_end);
 		if (!found) {
@@ -3310,7 +3348,6 @@ static noinline_for_stack int writepage_delalloc(struct inode *inode,
 		}
 		ret = btrfs_run_delalloc_range(inode, page, delalloc_start,
 				delalloc_end, &page_started, nr_written, wbc);
-		/* File system has been set read-only */
 		if (ret) {
 			SetPageError(page);
 			/*
@@ -4542,6 +4579,8 @@ int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
 	struct btrfs_path *path;
 	struct btrfs_root *root = BTRFS_I(inode)->root;
 	struct fiemap_cache cache = { 0 };
+	struct ulist *roots;
+	struct ulist *tmp_ulist;
 	int end = 0;
 	u64 em_start = 0;
 	u64 em_len = 0;
@@ -4555,6 +4594,13 @@ int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
 		return -ENOMEM;
 	path->leave_spinning = 1;
 
+	roots = ulist_alloc(GFP_KERNEL);
+	tmp_ulist = ulist_alloc(GFP_KERNEL);
+	if (!roots || !tmp_ulist) {
+		ret = -ENOMEM;
+		goto out_free_ulist;
+	}
+
 	start = round_down(start, btrfs_inode_sectorsize(inode));
 	len = round_up(max, btrfs_inode_sectorsize(inode)) - start;
 
@@ -4565,8 +4611,7 @@ int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
 	ret = btrfs_lookup_file_extent(NULL, root, path,
 			btrfs_ino(BTRFS_I(inode)), -1, 0);
 	if (ret < 0) {
-		btrfs_free_path(path);
-		return ret;
+		goto out_free_ulist;
 	} else {
 		WARN_ON(!ret);
 		if (ret == 1)
@@ -4675,7 +4720,7 @@ int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
 			 */
 			ret = btrfs_check_shared(root,
 						 btrfs_ino(BTRFS_I(inode)),
-						 bytenr);
+						 bytenr, roots, tmp_ulist);
 			if (ret < 0)
 				goto out_free;
 			if (ret)
@@ -4718,9 +4763,13 @@ out_free:
 		ret = emit_last_fiemap_cache(fieinfo, &cache);
 	free_extent_map(em);
 out:
-	btrfs_free_path(path);
 	unlock_extent_cached(&BTRFS_I(inode)->io_tree, start, start + len - 1,
 			     &cached_state);
+
+out_free_ulist:
+	btrfs_free_path(path);
+	ulist_free(roots);
+	ulist_free(tmp_ulist);
 	return ret;
 }
 
@@ -4808,7 +4857,7 @@ __alloc_extent_buffer(struct btrfs_fs_info *fs_info, u64 start,
 	eb->bflags = 0;
 	rwlock_init(&eb->lock);
 	atomic_set(&eb->blocking_readers, 0);
-	atomic_set(&eb->blocking_writers, 0);
+	eb->blocking_writers = 0;
 	eb->lock_nested = false;
 	init_waitqueue_head(&eb->write_lock_wq);
 	init_waitqueue_head(&eb->read_lock_wq);
@@ -4827,10 +4876,10 @@ __alloc_extent_buffer(struct btrfs_fs_info *fs_info, u64 start,
 	BUG_ON(len > MAX_INLINE_EXTENT_BUFFER_SIZE);
 
 #ifdef CONFIG_BTRFS_DEBUG
-	atomic_set(&eb->spinning_writers, 0);
+	eb->spinning_writers = 0;
 	atomic_set(&eb->spinning_readers, 0);
 	atomic_set(&eb->read_locks, 0);
-	atomic_set(&eb->write_locks, 0);
+	eb->write_locks = 0;
 #endif
 
 	return eb;
diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
index aa18a16a6ed7..401423b16976 100644
--- a/fs/btrfs/extent_io.h
+++ b/fs/btrfs/extent_io.h
@@ -167,7 +167,7 @@ struct extent_buffer {
 	struct rcu_head rcu_head;
 	pid_t lock_owner;
 
-	atomic_t blocking_writers;
+	int blocking_writers;
 	atomic_t blocking_readers;
 	bool lock_nested;
 	/* >= 0 if eb belongs to a log tree, -1 otherwise */
@@ -187,10 +187,10 @@ struct extent_buffer {
 	wait_queue_head_t read_lock_wq;
 	struct page *pages[INLINE_EXTENT_BUFFER_PAGES];
 #ifdef CONFIG_BTRFS_DEBUG
-	atomic_t spinning_writers;
+	int spinning_writers;
 	atomic_t spinning_readers;
 	atomic_t read_locks;
-	atomic_t write_locks;
+	int write_locks;
 	struct list_head leak_list;
 #endif
 };
@@ -497,7 +497,7 @@ void extent_clear_unlock_delalloc(struct inode *inode, u64 start, u64 end,
 				 u64 delalloc_end, struct page *locked_page,
 				 unsigned bits_to_clear,
 				 unsigned long page_ops);
-struct bio *btrfs_bio_alloc(struct block_device *bdev, u64 first_byte);
+struct bio *btrfs_bio_alloc(u64 first_byte);
 struct bio *btrfs_io_bio_alloc(unsigned int nr_iovecs);
 struct bio *btrfs_bio_clone(struct bio *bio);
 struct bio *btrfs_bio_clone_partial(struct bio *orig, int offset, int size);
@@ -549,7 +549,7 @@ int free_io_failure(struct extent_io_tree *failure_tree,
 		    struct extent_io_tree *io_tree,
 		    struct io_failure_record *rec);
 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
-bool find_lock_delalloc_range(struct inode *inode, struct extent_io_tree *tree,
+bool find_lock_delalloc_range(struct inode *inode,
 			     struct page *locked_page, u64 *start,
 			     u64 *end);
 #endif
diff --git a/fs/btrfs/file-item.c b/fs/btrfs/file-item.c
index d431ea8198e4..1a599f50837b 100644
--- a/fs/btrfs/file-item.c
+++ b/fs/btrfs/file-item.c
@@ -8,6 +8,7 @@
 #include <linux/pagemap.h>
 #include <linux/highmem.h>
 #include <linux/sched/mm.h>
+#include <crypto/hash.h>
 #include "ctree.h"
 #include "disk-io.h"
 #include "transaction.h"
@@ -22,9 +23,13 @@
 #define MAX_CSUM_ITEMS(r, size) (min_t(u32, __MAX_CSUM_ITEMS(r, size), \
 				       PAGE_SIZE))
 
-#define MAX_ORDERED_SUM_BYTES(fs_info) ((PAGE_SIZE - \
-				   sizeof(struct btrfs_ordered_sum)) / \
-				   sizeof(u32) * (fs_info)->sectorsize)
+static inline u32 max_ordered_sum_bytes(struct btrfs_fs_info *fs_info,
+					u16 csum_size)
+{
+	u32 ncsums = (PAGE_SIZE - sizeof(struct btrfs_ordered_sum)) / csum_size;
+
+	return ncsums * fs_info->sectorsize;
+}
 
 int btrfs_insert_file_extent(struct btrfs_trans_handle *trans,
 			     struct btrfs_root *root,
@@ -144,7 +149,7 @@ int btrfs_lookup_file_extent(struct btrfs_trans_handle *trans,
 }
 
 static blk_status_t __btrfs_lookup_bio_sums(struct inode *inode, struct bio *bio,
-				   u64 logical_offset, u32 *dst, int dio)
+				   u64 logical_offset, u8 *dst, int dio)
 {
 	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
 	struct bio_vec bvec;
@@ -182,7 +187,7 @@ static blk_status_t __btrfs_lookup_bio_sums(struct inode *inode, struct bio *bio
 		}
 		csum = btrfs_bio->csum;
 	} else {
-		csum = (u8 *)dst;
+		csum = dst;
 	}
 
 	if (bio->bi_iter.bi_size > PAGE_SIZE * 8)
@@ -211,7 +216,7 @@ static blk_status_t __btrfs_lookup_bio_sums(struct inode *inode, struct bio *bio
 		if (!dio)
 			offset = page_offset(bvec.bv_page) + bvec.bv_offset;
 		count = btrfs_find_ordered_sum(inode, offset, disk_bytenr,
-					       (u32 *)csum, nblocks);
+					       csum, nblocks);
 		if (count)
 			goto found;
 
@@ -283,7 +288,8 @@ next:
 	return 0;
 }
 
-blk_status_t btrfs_lookup_bio_sums(struct inode *inode, struct bio *bio, u32 *dst)
+blk_status_t btrfs_lookup_bio_sums(struct inode *inode, struct bio *bio,
+				   u8 *dst)
 {
 	return __btrfs_lookup_bio_sums(inode, bio, 0, dst, 0);
 }
@@ -374,7 +380,7 @@ int btrfs_lookup_csums_range(struct btrfs_root *root, u64 start, u64 end,
 				      struct btrfs_csum_item);
 		while (start < csum_end) {
 			size = min_t(size_t, csum_end - start,
-				     MAX_ORDERED_SUM_BYTES(fs_info));
+				     max_ordered_sum_bytes(fs_info, csum_size));
 			sums = kzalloc(btrfs_ordered_sum_size(fs_info, size),
 				       GFP_NOFS);
 			if (!sums) {
@@ -427,6 +433,7 @@ blk_status_t btrfs_csum_one_bio(struct inode *inode, struct bio *bio,
 		       u64 file_start, int contig)
 {
 	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
+	SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
 	struct btrfs_ordered_sum *sums;
 	struct btrfs_ordered_extent *ordered = NULL;
 	char *data;
@@ -439,6 +446,7 @@ blk_status_t btrfs_csum_one_bio(struct inode *inode, struct bio *bio,
 	int i;
 	u64 offset;
 	unsigned nofs_flag;
+	const u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
 
 	nofs_flag = memalloc_nofs_save();
 	sums = kvzalloc(btrfs_ordered_sum_size(fs_info, bio->bi_iter.bi_size),
@@ -459,6 +467,8 @@ blk_status_t btrfs_csum_one_bio(struct inode *inode, struct bio *bio,
 	sums->bytenr = (u64)bio->bi_iter.bi_sector << 9;
 	index = 0;
 
+	shash->tfm = fs_info->csum_shash;
+
 	bio_for_each_segment(bvec, bio, iter) {
 		if (!contig)
 			offset = page_offset(bvec.bv_page) + bvec.bv_offset;
@@ -498,17 +508,14 @@ blk_status_t btrfs_csum_one_bio(struct inode *inode, struct bio *bio,
 				index = 0;
 			}
 
-			sums->sums[index] = ~(u32)0;
+			crypto_shash_init(shash);
 			data = kmap_atomic(bvec.bv_page);
-			sums->sums[index]
-				= btrfs_csum_data(data + bvec.bv_offset
-						+ (i * fs_info->sectorsize),
-						sums->sums[index],
-						fs_info->sectorsize);
+			crypto_shash_update(shash, data + bvec.bv_offset
+					    + (i * fs_info->sectorsize),
+					    fs_info->sectorsize);
 			kunmap_atomic(data);
-			btrfs_csum_final(sums->sums[index],
-					(char *)(sums->sums + index));
-			index++;
+			crypto_shash_final(shash, (char *)(sums->sums + index));
+			index += csum_size;
 			offset += fs_info->sectorsize;
 			this_sum_bytes += fs_info->sectorsize;
 			total_bytes += fs_info->sectorsize;
@@ -904,9 +911,9 @@ found:
 	write_extent_buffer(leaf, sums->sums + index, (unsigned long)item,
 			    ins_size);
 
+	index += ins_size;
 	ins_size /= csum_size;
 	total_bytes += ins_size * fs_info->sectorsize;
-	index += ins_size;
 
 	btrfs_mark_buffer_dirty(path->nodes[0]);
 	if (total_bytes < sums->len) {
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 89f5be2bfb43..58a18ed11546 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -26,6 +26,7 @@
 #include "volumes.h"
 #include "qgroup.h"
 #include "compression.h"
+#include "delalloc-space.h"
 
 static struct kmem_cache *btrfs_inode_defrag_cachep;
 /*
@@ -1550,30 +1551,20 @@ static noinline int check_can_nocow(struct btrfs_inode *inode, loff_t pos,
 {
 	struct btrfs_fs_info *fs_info = inode->root->fs_info;
 	struct btrfs_root *root = inode->root;
-	struct btrfs_ordered_extent *ordered;
 	u64 lockstart, lockend;
 	u64 num_bytes;
 	int ret;
 
 	ret = btrfs_start_write_no_snapshotting(root);
 	if (!ret)
-		return -ENOSPC;
+		return -EAGAIN;
 
 	lockstart = round_down(pos, fs_info->sectorsize);
 	lockend = round_up(pos + *write_bytes,
 			   fs_info->sectorsize) - 1;
 
-	while (1) {
-		lock_extent(&inode->io_tree, lockstart, lockend);
-		ordered = btrfs_lookup_ordered_range(inode, lockstart,
-						     lockend - lockstart + 1);
-		if (!ordered) {
-			break;
-		}
-		unlock_extent(&inode->io_tree, lockstart, lockend);
-		btrfs_start_ordered_extent(&inode->vfs_inode, ordered, 1);
-		btrfs_put_ordered_extent(ordered);
-	}
+	btrfs_lock_and_flush_ordered_range(&inode->io_tree, inode, lockstart,
+					   lockend, NULL);
 
 	num_bytes = lockend - lockstart + 1;
 	ret = can_nocow_extent(&inode->vfs_inode, lockstart, &num_bytes,
@@ -2721,6 +2712,11 @@ out_only_mutex:
 		 * for detecting, at fsync time, if the inode isn't yet in the
 		 * log tree or it's there but not up to date.
 		 */
+		struct timespec64 now = current_time(inode);
+
+		inode_inc_iversion(inode);
+		inode->i_mtime = now;
+		inode->i_ctime = now;
 		trans = btrfs_start_transaction(root, 1);
 		if (IS_ERR(trans)) {
 			err = PTR_ERR(trans);
@@ -2801,9 +2797,9 @@ static int btrfs_fallocate_update_isize(struct inode *inode,
 }
 
 enum {
-	RANGE_BOUNDARY_WRITTEN_EXTENT = 0,
-	RANGE_BOUNDARY_PREALLOC_EXTENT = 1,
-	RANGE_BOUNDARY_HOLE = 2,
+	RANGE_BOUNDARY_WRITTEN_EXTENT,
+	RANGE_BOUNDARY_PREALLOC_EXTENT,
+	RANGE_BOUNDARY_HOLE,
 };
 
 static int btrfs_zero_range_check_range_boundary(struct inode *inode,
diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c
index f74dc259307b..062be9dde4c6 100644
--- a/fs/btrfs/free-space-cache.c
+++ b/fs/btrfs/free-space-cache.c
@@ -18,6 +18,8 @@
 #include "extent_io.h"
 #include "inode-map.h"
 #include "volumes.h"
+#include "space-info.h"
+#include "delalloc-space.h"
 
 #define BITS_PER_BITMAP		(PAGE_SIZE * 8UL)
 #define MAX_CACHE_BYTES_PER_GIG	SZ_32K
@@ -465,9 +467,8 @@ static void io_ctl_set_crc(struct btrfs_io_ctl *io_ctl, int index)
 	if (index == 0)
 		offset = sizeof(u32) * io_ctl->num_pages;
 
-	crc = btrfs_csum_data(io_ctl->orig + offset, crc,
-			      PAGE_SIZE - offset);
-	btrfs_csum_final(crc, (u8 *)&crc);
+	crc = btrfs_crc32c(crc, io_ctl->orig + offset, PAGE_SIZE - offset);
+	btrfs_crc32c_final(crc, (u8 *)&crc);
 	io_ctl_unmap_page(io_ctl);
 	tmp = page_address(io_ctl->pages[0]);
 	tmp += index;
@@ -493,9 +494,8 @@ static int io_ctl_check_crc(struct btrfs_io_ctl *io_ctl, int index)
 	val = *tmp;
 
 	io_ctl_map_page(io_ctl, 0);
-	crc = btrfs_csum_data(io_ctl->orig + offset, crc,
-			      PAGE_SIZE - offset);
-	btrfs_csum_final(crc, (u8 *)&crc);
+	crc = btrfs_crc32c(crc, io_ctl->orig + offset, PAGE_SIZE - offset);
+	btrfs_crc32c_final(crc, (u8 *)&crc);
 	if (val != crc) {
 		btrfs_err_rl(io_ctl->fs_info,
 			"csum mismatch on free space cache");
@@ -3166,8 +3166,8 @@ static int do_trimming(struct btrfs_block_group_cache *block_group,
 			space_info->bytes_readonly += reserved_bytes;
 		block_group->reserved -= reserved_bytes;
 		space_info->bytes_reserved -= reserved_bytes;
-		spin_unlock(&space_info->lock);
 		spin_unlock(&block_group->lock);
+		spin_unlock(&space_info->lock);
 	}
 
 	return ret;
@@ -3358,7 +3358,7 @@ void btrfs_put_block_group_trimming(struct btrfs_block_group_cache *block_group)
 
 	if (cleanup) {
 		mutex_lock(&fs_info->chunk_mutex);
-		em_tree = &fs_info->mapping_tree.map_tree;
+		em_tree = &fs_info->mapping_tree;
 		write_lock(&em_tree->lock);
 		em = lookup_extent_mapping(em_tree, block_group->key.objectid,
 					   1);
diff --git a/fs/btrfs/inode-map.c b/fs/btrfs/inode-map.c
index ffca2abf13d0..2e8bb402050b 100644
--- a/fs/btrfs/inode-map.c
+++ b/fs/btrfs/inode-map.c
@@ -11,6 +11,7 @@
 #include "free-space-cache.h"
 #include "inode-map.h"
 #include "transaction.h"
+#include "delalloc-space.h"
 
 static int caching_kthread(void *data)
 {
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index a2aabdb85226..1af069a9a0c7 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -47,6 +47,7 @@
 #include "props.h"
 #include "qgroup.h"
 #include "dedupe.h"
+#include "delalloc-space.h"
 
 struct btrfs_iget_args {
 	struct btrfs_key *location;
@@ -1932,17 +1933,19 @@ int btrfs_bio_fits_in_stripe(struct page *page, size_t size, struct bio *bio,
 	u64 length = 0;
 	u64 map_length;
 	int ret;
+	struct btrfs_io_geometry geom;
 
 	if (bio_flags & EXTENT_BIO_COMPRESSED)
 		return 0;
 
 	length = bio->bi_iter.bi_size;
 	map_length = length;
-	ret = btrfs_map_block(fs_info, btrfs_op(bio), logical, &map_length,
-			      NULL, 0);
+	ret = btrfs_get_io_geometry(fs_info, btrfs_op(bio), logical, map_length,
+				    &geom);
 	if (ret < 0)
 		return ret;
-	if (map_length < length + size)
+
+	if (geom.len < length + size)
 		return 1;
 	return 0;
 }
@@ -3203,16 +3206,23 @@ static int __readpage_endio_check(struct inode *inode,
 				  int icsum, struct page *page,
 				  int pgoff, u64 start, size_t len)
 {
+	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
+	SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
 	char *kaddr;
-	u32 csum_expected;
-	u32 csum = ~(u32)0;
+	u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
+	u8 *csum_expected;
+	u8 csum[BTRFS_CSUM_SIZE];
 
-	csum_expected = *(((u32 *)io_bio->csum) + icsum);
+	csum_expected = ((u8 *)io_bio->csum) + icsum * csum_size;
 
 	kaddr = kmap_atomic(page);
-	csum = btrfs_csum_data(kaddr + pgoff, csum,  len);
-	btrfs_csum_final(csum, (u8 *)&csum);
-	if (csum != csum_expected)
+	shash->tfm = fs_info->csum_shash;
+
+	crypto_shash_init(shash);
+	crypto_shash_update(shash, kaddr + pgoff, len);
+	crypto_shash_final(shash, csum);
+
+	if (memcmp(csum, csum_expected, csum_size))
 		goto zeroit;
 
 	kunmap_atomic(kaddr);
@@ -3286,6 +3296,28 @@ void btrfs_add_delayed_iput(struct inode *inode)
 		wake_up_process(fs_info->cleaner_kthread);
 }
 
+static void run_delayed_iput_locked(struct btrfs_fs_info *fs_info,
+				    struct btrfs_inode *inode)
+{
+	list_del_init(&inode->delayed_iput);
+	spin_unlock(&fs_info->delayed_iput_lock);
+	iput(&inode->vfs_inode);
+	if (atomic_dec_and_test(&fs_info->nr_delayed_iputs))
+		wake_up(&fs_info->delayed_iputs_wait);
+	spin_lock(&fs_info->delayed_iput_lock);
+}
+
+static void btrfs_run_delayed_iput(struct btrfs_fs_info *fs_info,
+				   struct btrfs_inode *inode)
+{
+	if (!list_empty(&inode->delayed_iput)) {
+		spin_lock(&fs_info->delayed_iput_lock);
+		if (!list_empty(&inode->delayed_iput))
+			run_delayed_iput_locked(fs_info, inode);
+		spin_unlock(&fs_info->delayed_iput_lock);
+	}
+}
+
 void btrfs_run_delayed_iputs(struct btrfs_fs_info *fs_info)
 {
 
@@ -3295,12 +3327,7 @@ void btrfs_run_delayed_iputs(struct btrfs_fs_info *fs_info)
 
 		inode = list_first_entry(&fs_info->delayed_iputs,
 				struct btrfs_inode, delayed_iput);
-		list_del_init(&inode->delayed_iput);
-		spin_unlock(&fs_info->delayed_iput_lock);
-		iput(&inode->vfs_inode);
-		if (atomic_dec_and_test(&fs_info->nr_delayed_iputs))
-			wake_up(&fs_info->delayed_iputs_wait);
-		spin_lock(&fs_info->delayed_iput_lock);
+		run_delayed_iput_locked(fs_info, inode);
 	}
 	spin_unlock(&fs_info->delayed_iput_lock);
 }
@@ -3935,9 +3962,7 @@ static int __btrfs_unlink_inode(struct btrfs_trans_handle *trans,
 	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct btrfs_path *path;
 	int ret = 0;
-	struct extent_buffer *leaf;
 	struct btrfs_dir_item *di;
-	struct btrfs_key key;
 	u64 index;
 	u64 ino = btrfs_ino(inode);
 	u64 dir_ino = btrfs_ino(dir);
@@ -3955,8 +3980,6 @@ static int __btrfs_unlink_inode(struct btrfs_trans_handle *trans,
 		ret = di ? PTR_ERR(di) : -ENOENT;
 		goto err;
 	}
-	leaf = path->nodes[0];
-	btrfs_dir_item_key_to_cpu(leaf, di, &key);
 	ret = btrfs_delete_one_dir_name(trans, root, path, di);
 	if (ret)
 		goto err;
@@ -4009,6 +4032,17 @@ skip_backref:
 		ret = 0;
 	else if (ret)
 		btrfs_abort_transaction(trans, ret);
+
+	/*
+	 * If we have a pending delayed iput we could end up with the final iput
+	 * being run in btrfs-cleaner context.  If we have enough of these built
+	 * up we can end up burning a lot of time in btrfs-cleaner without any
+	 * way to throttle the unlinks.  Since we're currently holding a ref on
+	 * the inode we can run the delayed iput here without any issues as the
+	 * final iput won't be done until after we drop the ref we're currently
+	 * holding.
+	 */
+	btrfs_run_delayed_iput(fs_info, inode);
 err:
 	btrfs_free_path(path);
 	if (ret)
@@ -5008,21 +5042,8 @@ int btrfs_cont_expand(struct inode *inode, loff_t oldsize, loff_t size)
 	if (size <= hole_start)
 		return 0;
 
-	while (1) {
-		struct btrfs_ordered_extent *ordered;
-
-		lock_extent_bits(io_tree, hole_start, block_end - 1,
-				 &cached_state);
-		ordered = btrfs_lookup_ordered_range(BTRFS_I(inode), hole_start,
-						     block_end - hole_start);
-		if (!ordered)
-			break;
-		unlock_extent_cached(io_tree, hole_start, block_end - 1,
-				     &cached_state);
-		btrfs_start_ordered_extent(inode, ordered, 1);
-		btrfs_put_ordered_extent(ordered);
-	}
-
+	btrfs_lock_and_flush_ordered_range(io_tree, BTRFS_I(inode), hole_start,
+					   block_end - 1, &cached_state);
 	cur_offset = hole_start;
 	while (1) {
 		em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, cur_offset,
@@ -8318,22 +8339,21 @@ static int btrfs_submit_direct_hook(struct btrfs_dio_private *dip)
 	struct bio *orig_bio = dip->orig_bio;
 	u64 start_sector = orig_bio->bi_iter.bi_sector;
 	u64 file_offset = dip->logical_offset;
-	u64 map_length;
 	int async_submit = 0;
 	u64 submit_len;
 	int clone_offset = 0;
 	int clone_len;
 	int ret;
 	blk_status_t status;
+	struct btrfs_io_geometry geom;
 
-	map_length = orig_bio->bi_iter.bi_size;
-	submit_len = map_length;
-	ret = btrfs_map_block(fs_info, btrfs_op(orig_bio), start_sector << 9,
-			      &map_length, NULL, 0);
+	submit_len = orig_bio->bi_iter.bi_size;
+	ret = btrfs_get_io_geometry(fs_info, btrfs_op(orig_bio),
+				    start_sector << 9, submit_len, &geom);
 	if (ret)
 		return -EIO;
 
-	if (map_length >= submit_len) {
+	if (geom.len >= submit_len) {
 		bio = orig_bio;
 		dip->flags |= BTRFS_DIO_ORIG_BIO_SUBMITTED;
 		goto submit;
@@ -8346,10 +8366,10 @@ static int btrfs_submit_direct_hook(struct btrfs_dio_private *dip)
 		async_submit = 1;
 
 	/* bio split */
-	ASSERT(map_length <= INT_MAX);
+	ASSERT(geom.len <= INT_MAX);
 	atomic_inc(&dip->pending_bios);
 	do {
-		clone_len = min_t(int, submit_len, map_length);
+		clone_len = min_t(int, submit_len, geom.len);
 
 		/*
 		 * This will never fail as it's passing GPF_NOFS and
@@ -8386,9 +8406,8 @@ static int btrfs_submit_direct_hook(struct btrfs_dio_private *dip)
 		start_sector += clone_len >> 9;
 		file_offset += clone_len;
 
-		map_length = submit_len;
-		ret = btrfs_map_block(fs_info, btrfs_op(orig_bio),
-				      start_sector << 9, &map_length, NULL, 0);
+		ret = btrfs_get_io_geometry(fs_info, btrfs_op(orig_bio),
+				      start_sector << 9, submit_len, &geom);
 		if (ret)
 			goto out_err;
 	} while (submit_len > 0);
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index cfeff1b8dce0..818f7ec8bb0e 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -43,6 +43,8 @@
 #include "qgroup.h"
 #include "tree-log.h"
 #include "compression.h"
+#include "space-info.h"
+#include "delalloc-space.h"
 
 #ifdef CONFIG_64BIT
 /* If we have a 32-bit userspace and 64-bit kernel, then the UAPI
@@ -3993,6 +3995,27 @@ static int btrfs_remap_file_range_prep(struct file *file_in, loff_t pos_in,
 	if (!same_inode)
 		inode_dio_wait(inode_out);
 
+	/*
+	 * Workaround to make sure NOCOW buffered write reach disk as NOCOW.
+	 *
+	 * Btrfs' back references do not have a block level granularity, they
+	 * work at the whole extent level.
+	 * NOCOW buffered write without data space reserved may not be able
+	 * to fall back to CoW due to lack of data space, thus could cause
+	 * data loss.
+	 *
+	 * Here we take a shortcut by flushing the whole inode, so that all
+	 * nocow write should reach disk as nocow before we increase the
+	 * reference of the extent. We could do better by only flushing NOCOW
+	 * data, but that needs extra accounting.
+	 *
+	 * Also we don't need to check ASYNC_EXTENT, as async extent will be
+	 * CoWed anyway, not affecting nocow part.
+	 */
+	ret = filemap_flush(inode_in->i_mapping);
+	if (ret < 0)
+		return ret;
+
 	ret = btrfs_wait_ordered_range(inode_in, ALIGN_DOWN(pos_in, bs),
 				       wb_len);
 	if (ret < 0)
diff --git a/fs/btrfs/locking.c b/fs/btrfs/locking.c
index 2f6c3c7851ed..98fccce4208c 100644
--- a/fs/btrfs/locking.c
+++ b/fs/btrfs/locking.c
@@ -15,19 +15,19 @@
 #ifdef CONFIG_BTRFS_DEBUG
 static void btrfs_assert_spinning_writers_get(struct extent_buffer *eb)
 {
-	WARN_ON(atomic_read(&eb->spinning_writers));
-	atomic_inc(&eb->spinning_writers);
+	WARN_ON(eb->spinning_writers);
+	eb->spinning_writers++;
 }
 
 static void btrfs_assert_spinning_writers_put(struct extent_buffer *eb)
 {
-	WARN_ON(atomic_read(&eb->spinning_writers) != 1);
-	atomic_dec(&eb->spinning_writers);
+	WARN_ON(eb->spinning_writers != 1);
+	eb->spinning_writers--;
 }
 
 static void btrfs_assert_no_spinning_writers(struct extent_buffer *eb)
 {
-	WARN_ON(atomic_read(&eb->spinning_writers));
+	WARN_ON(eb->spinning_writers);
 }
 
 static void btrfs_assert_spinning_readers_get(struct extent_buffer *eb)
@@ -58,17 +58,17 @@ static void btrfs_assert_tree_read_locked(struct extent_buffer *eb)
 
 static void btrfs_assert_tree_write_locks_get(struct extent_buffer *eb)
 {
-	atomic_inc(&eb->write_locks);
+	eb->write_locks++;
 }
 
 static void btrfs_assert_tree_write_locks_put(struct extent_buffer *eb)
 {
-	atomic_dec(&eb->write_locks);
+	eb->write_locks--;
 }
 
 void btrfs_assert_tree_locked(struct extent_buffer *eb)
 {
-	BUG_ON(!atomic_read(&eb->write_locks));
+	BUG_ON(!eb->write_locks);
 }
 
 #else
@@ -111,10 +111,10 @@ void btrfs_set_lock_blocking_write(struct extent_buffer *eb)
 	 */
 	if (eb->lock_nested && current->pid == eb->lock_owner)
 		return;
-	if (atomic_read(&eb->blocking_writers) == 0) {
+	if (eb->blocking_writers == 0) {
 		btrfs_assert_spinning_writers_put(eb);
 		btrfs_assert_tree_locked(eb);
-		atomic_inc(&eb->blocking_writers);
+		eb->blocking_writers++;
 		write_unlock(&eb->lock);
 	}
 }
@@ -148,12 +148,11 @@ void btrfs_clear_lock_blocking_write(struct extent_buffer *eb)
 	 */
 	if (eb->lock_nested && current->pid == eb->lock_owner)
 		return;
-	BUG_ON(atomic_read(&eb->blocking_writers) != 1);
 	write_lock(&eb->lock);
+	BUG_ON(eb->blocking_writers != 1);
 	btrfs_assert_spinning_writers_get(eb);
-	/* atomic_dec_and_test implies a barrier */
-	if (atomic_dec_and_test(&eb->blocking_writers))
-		cond_wake_up_nomb(&eb->write_lock_wq);
+	if (--eb->blocking_writers == 0)
+		cond_wake_up(&eb->write_lock_wq);
 }
 
 /*
@@ -167,12 +166,10 @@ void btrfs_tree_read_lock(struct extent_buffer *eb)
 	if (trace_btrfs_tree_read_lock_enabled())
 		start_ns = ktime_get_ns();
 again:
-	BUG_ON(!atomic_read(&eb->blocking_writers) &&
-	       current->pid == eb->lock_owner);
-
 	read_lock(&eb->lock);
-	if (atomic_read(&eb->blocking_writers) &&
-	    current->pid == eb->lock_owner) {
+	BUG_ON(eb->blocking_writers == 0 &&
+	       current->pid == eb->lock_owner);
+	if (eb->blocking_writers && current->pid == eb->lock_owner) {
 		/*
 		 * This extent is already write-locked by our thread. We allow
 		 * an additional read lock to be added because it's for the same
@@ -185,10 +182,10 @@ again:
 		trace_btrfs_tree_read_lock(eb, start_ns);
 		return;
 	}
-	if (atomic_read(&eb->blocking_writers)) {
+	if (eb->blocking_writers) {
 		read_unlock(&eb->lock);
 		wait_event(eb->write_lock_wq,
-			   atomic_read(&eb->blocking_writers) == 0);
+			   eb->blocking_writers == 0);
 		goto again;
 	}
 	btrfs_assert_tree_read_locks_get(eb);
@@ -203,11 +200,11 @@ again:
  */
 int btrfs_tree_read_lock_atomic(struct extent_buffer *eb)
 {
-	if (atomic_read(&eb->blocking_writers))
+	if (eb->blocking_writers)
 		return 0;
 
 	read_lock(&eb->lock);
-	if (atomic_read(&eb->blocking_writers)) {
+	if (eb->blocking_writers) {
 		read_unlock(&eb->lock);
 		return 0;
 	}
@@ -223,13 +220,13 @@ int btrfs_tree_read_lock_atomic(struct extent_buffer *eb)
  */
 int btrfs_try_tree_read_lock(struct extent_buffer *eb)
 {
-	if (atomic_read(&eb->blocking_writers))
+	if (eb->blocking_writers)
 		return 0;
 
 	if (!read_trylock(&eb->lock))
 		return 0;
 
-	if (atomic_read(&eb->blocking_writers)) {
+	if (eb->blocking_writers) {
 		read_unlock(&eb->lock);
 		return 0;
 	}
@@ -245,13 +242,11 @@ int btrfs_try_tree_read_lock(struct extent_buffer *eb)
  */
 int btrfs_try_tree_write_lock(struct extent_buffer *eb)
 {
-	if (atomic_read(&eb->blocking_writers) ||
-	    atomic_read(&eb->blocking_readers))
+	if (eb->blocking_writers || atomic_read(&eb->blocking_readers))
 		return 0;
 
 	write_lock(&eb->lock);
-	if (atomic_read(&eb->blocking_writers) ||
-	    atomic_read(&eb->blocking_readers)) {
+	if (eb->blocking_writers || atomic_read(&eb->blocking_readers)) {
 		write_unlock(&eb->lock);
 		return 0;
 	}
@@ -322,10 +317,9 @@ void btrfs_tree_lock(struct extent_buffer *eb)
 	WARN_ON(eb->lock_owner == current->pid);
 again:
 	wait_event(eb->read_lock_wq, atomic_read(&eb->blocking_readers) == 0);
-	wait_event(eb->write_lock_wq, atomic_read(&eb->blocking_writers) == 0);
+	wait_event(eb->write_lock_wq, eb->blocking_writers == 0);
 	write_lock(&eb->lock);
-	if (atomic_read(&eb->blocking_readers) ||
-	    atomic_read(&eb->blocking_writers)) {
+	if (atomic_read(&eb->blocking_readers) || eb->blocking_writers) {
 		write_unlock(&eb->lock);
 		goto again;
 	}
@@ -340,7 +334,7 @@ again:
  */
 void btrfs_tree_unlock(struct extent_buffer *eb)
 {
-	int blockers = atomic_read(&eb->blocking_writers);
+	int blockers = eb->blocking_writers;
 
 	BUG_ON(blockers > 1);
 
@@ -351,7 +345,7 @@ void btrfs_tree_unlock(struct extent_buffer *eb)
 
 	if (blockers) {
 		btrfs_assert_no_spinning_writers(eb);
-		atomic_dec(&eb->blocking_writers);
+		eb->blocking_writers--;
 		/* Use the lighter barrier after atomic */
 		smp_mb__after_atomic();
 		cond_wake_up_nomb(&eb->write_lock_wq);
diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c
index 52889da69113..1744ba8b2754 100644
--- a/fs/btrfs/ordered-data.c
+++ b/fs/btrfs/ordered-data.c
@@ -13,6 +13,7 @@
 #include "extent_io.h"
 #include "disk-io.h"
 #include "compression.h"
+#include "delalloc-space.h"
 
 static struct kmem_cache *btrfs_ordered_extent_cache;
 
@@ -924,14 +925,16 @@ out:
  * be reclaimed before their checksum is actually put into the btree
  */
 int btrfs_find_ordered_sum(struct inode *inode, u64 offset, u64 disk_bytenr,
-			   u32 *sum, int len)
+			   u8 *sum, int len)
 {
+	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
 	struct btrfs_ordered_sum *ordered_sum;
 	struct btrfs_ordered_extent *ordered;
 	struct btrfs_ordered_inode_tree *tree = &BTRFS_I(inode)->ordered_tree;
 	unsigned long num_sectors;
 	unsigned long i;
 	u32 sectorsize = btrfs_inode_sectorsize(inode);
+	const u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
 	int index = 0;
 
 	ordered = btrfs_lookup_ordered_extent(inode, offset);
@@ -947,10 +950,10 @@ int btrfs_find_ordered_sum(struct inode *inode, u64 offset, u64 disk_bytenr,
 			num_sectors = ordered_sum->len >>
 				      inode->i_sb->s_blocksize_bits;
 			num_sectors = min_t(int, len - index, num_sectors - i);
-			memcpy(sum + index, ordered_sum->sums + i,
-			       num_sectors);
+			memcpy(sum + index, ordered_sum->sums + i * csum_size,
+			       num_sectors * csum_size);
 
-			index += (int)num_sectors;
+			index += (int)num_sectors * csum_size;
 			if (index == len)
 				goto out;
 			disk_bytenr += num_sectors * sectorsize;
@@ -962,6 +965,51 @@ out:
 	return index;
 }
 
+/*
+ * btrfs_flush_ordered_range - Lock the passed range and ensures all pending
+ * ordered extents in it are run to completion.
+ *
+ * @tree:         IO tree used for locking out other users of the range
+ * @inode:        Inode whose ordered tree is to be searched
+ * @start:        Beginning of range to flush
+ * @end:          Last byte of range to lock
+ * @cached_state: If passed, will return the extent state responsible for the
+ * locked range. It's the caller's responsibility to free the cached state.
+ *
+ * This function always returns with the given range locked, ensuring after it's
+ * called no order extent can be pending.
+ */
+void btrfs_lock_and_flush_ordered_range(struct extent_io_tree *tree,
+					struct btrfs_inode *inode, u64 start,
+					u64 end,
+					struct extent_state **cached_state)
+{
+	struct btrfs_ordered_extent *ordered;
+	struct extent_state *cachedp = NULL;
+
+	if (cached_state)
+		cachedp = *cached_state;
+
+	while (1) {
+		lock_extent_bits(tree, start, end, &cachedp);
+		ordered = btrfs_lookup_ordered_range(inode, start,
+						     end - start + 1);
+		if (!ordered) {
+			/*
+			 * If no external cached_state has been passed then
+			 * decrement the extra ref taken for cachedp since we
+			 * aren't exposing it outside of this function
+			 */
+			if (!cached_state)
+				refcount_dec(&cachedp->refs);
+			break;
+		}
+		unlock_extent_cached(tree, start, end, &cachedp);
+		btrfs_start_ordered_extent(&inode->vfs_inode, ordered, 1);
+		btrfs_put_ordered_extent(ordered);
+	}
+}
+
 int __init ordered_data_init(void)
 {
 	btrfs_ordered_extent_cache = kmem_cache_create("btrfs_ordered_extent",
diff --git a/fs/btrfs/ordered-data.h b/fs/btrfs/ordered-data.h
index 4c5991c3de14..5204171ea962 100644
--- a/fs/btrfs/ordered-data.h
+++ b/fs/btrfs/ordered-data.h
@@ -23,7 +23,7 @@ struct btrfs_ordered_sum {
 	int len;
 	struct list_head list;
 	/* last field is a variable length array of csums */
-	u32 sums[];
+	u8 sums[];
 };
 
 /*
@@ -183,11 +183,15 @@ struct btrfs_ordered_extent *btrfs_lookup_ordered_range(
 int btrfs_ordered_update_i_size(struct inode *inode, u64 offset,
 				struct btrfs_ordered_extent *ordered);
 int btrfs_find_ordered_sum(struct inode *inode, u64 offset, u64 disk_bytenr,
-			   u32 *sum, int len);
+			   u8 *sum, int len);
 u64 btrfs_wait_ordered_extents(struct btrfs_root *root, u64 nr,
 			       const u64 range_start, const u64 range_len);
 u64 btrfs_wait_ordered_roots(struct btrfs_fs_info *fs_info, u64 nr,
 			      const u64 range_start, const u64 range_len);
+void btrfs_lock_and_flush_ordered_range(struct extent_io_tree *tree,
+					struct btrfs_inode *inode, u64 start,
+					u64 end,
+					struct extent_state **cached_state);
 int __init ordered_data_init(void);
 void __cold ordered_data_exit(void);
 
diff --git a/fs/btrfs/print-tree.c b/fs/btrfs/print-tree.c
index 1141ca5fae6a..9cb50577d982 100644
--- a/fs/btrfs/print-tree.c
+++ b/fs/btrfs/print-tree.c
@@ -153,11 +153,11 @@ static void print_eb_refs_lock(struct extent_buffer *eb)
 #ifdef CONFIG_BTRFS_DEBUG
 	btrfs_info(eb->fs_info,
 "refs %u lock (w:%d r:%d bw:%d br:%d sw:%d sr:%d) lock_owner %u current %u",
-		   atomic_read(&eb->refs), atomic_read(&eb->write_locks),
+		   atomic_read(&eb->refs), eb->write_locks,
 		   atomic_read(&eb->read_locks),
-		   atomic_read(&eb->blocking_writers),
+		   eb->blocking_writers,
 		   atomic_read(&eb->blocking_readers),
-		   atomic_read(&eb->spinning_writers),
+		   eb->spinning_writers,
 		   atomic_read(&eb->spinning_readers),
 		   eb->lock_owner, current->pid);
 #endif
diff --git a/fs/btrfs/props.c b/fs/btrfs/props.c
index a9e2e66152ee..e0469816c678 100644
--- a/fs/btrfs/props.c
+++ b/fs/btrfs/props.c
@@ -257,11 +257,7 @@ static int prop_compression_validate(const char *value, size_t len)
 	if (!value)
 		return 0;
 
-	if (!strncmp("lzo", value, 3))
-		return 0;
-	else if (!strncmp("zlib", value, 4))
-		return 0;
-	else if (!strncmp("zstd", value, 4))
+	if (btrfs_compress_is_valid_type(value, len))
 		return 0;
 
 	return -EINVAL;
@@ -341,7 +337,7 @@ static int inherit_props(struct btrfs_trans_handle *trans,
 	for (i = 0; i < ARRAY_SIZE(prop_handlers); i++) {
 		const struct prop_handler *h = &prop_handlers[i];
 		const char *value;
-		u64 num_bytes;
+		u64 num_bytes = 0;
 
 		if (!h->inheritable)
 			continue;
diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c
index 3e6ffbbd8b0a..f8a3c1b0a15a 100644
--- a/fs/btrfs/qgroup.c
+++ b/fs/btrfs/qgroup.c
@@ -2614,6 +2614,7 @@ int btrfs_qgroup_inherit(struct btrfs_trans_handle *trans, u64 srcid,
 	int ret = 0;
 	int i;
 	u64 *i_qgroups;
+	bool committing = false;
 	struct btrfs_fs_info *fs_info = trans->fs_info;
 	struct btrfs_root *quota_root;
 	struct btrfs_qgroup *srcgroup;
@@ -2621,7 +2622,25 @@ int btrfs_qgroup_inherit(struct btrfs_trans_handle *trans, u64 srcid,
 	u32 level_size = 0;
 	u64 nums;
 
-	mutex_lock(&fs_info->qgroup_ioctl_lock);
+	/*
+	 * There are only two callers of this function.
+	 *
+	 * One in create_subvol() in the ioctl context, which needs to hold
+	 * the qgroup_ioctl_lock.
+	 *
+	 * The other one in create_pending_snapshot() where no other qgroup
+	 * code can modify the fs as they all need to either start a new trans
+	 * or hold a trans handler, thus we don't need to hold
+	 * qgroup_ioctl_lock.
+	 * This would avoid long and complex lock chain and make lockdep happy.
+	 */
+	spin_lock(&fs_info->trans_lock);
+	if (trans->transaction->state == TRANS_STATE_COMMIT_DOING)
+		committing = true;
+	spin_unlock(&fs_info->trans_lock);
+
+	if (!committing)
+		mutex_lock(&fs_info->qgroup_ioctl_lock);
 	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags))
 		goto out;
 
@@ -2785,7 +2804,8 @@ int btrfs_qgroup_inherit(struct btrfs_trans_handle *trans, u64 srcid,
 unlock:
 	spin_unlock(&fs_info->qgroup_lock);
 out:
-	mutex_unlock(&fs_info->qgroup_ioctl_lock);
+	if (!committing)
+		mutex_unlock(&fs_info->qgroup_ioctl_lock);
 	return ret;
 }
 
diff --git a/fs/btrfs/raid56.h b/fs/btrfs/raid56.h
index f5d4c13a8dbc..2503485db859 100644
--- a/fs/btrfs/raid56.h
+++ b/fs/btrfs/raid56.h
@@ -7,7 +7,7 @@
 #ifndef BTRFS_RAID56_H
 #define BTRFS_RAID56_H
 
-static inline int nr_parity_stripes(struct map_lookup *map)
+static inline int nr_parity_stripes(const struct map_lookup *map)
 {
 	if (map->type & BTRFS_BLOCK_GROUP_RAID5)
 		return 1;
@@ -17,7 +17,7 @@ static inline int nr_parity_stripes(struct map_lookup *map)
 		return 0;
 }
 
-static inline int nr_data_stripes(struct map_lookup *map)
+static inline int nr_data_stripes(const struct map_lookup *map)
 {
 	return map->num_stripes - nr_parity_stripes(map);
 }
diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index 22a3c69864fa..7f219851fa23 100644
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -20,6 +20,7 @@
 #include "inode-map.h"
 #include "qgroup.h"
 #include "print-tree.h"
+#include "delalloc-space.h"
 
 /*
  * backref_node, mapping_node and tree_block start with this
diff --git a/fs/btrfs/root-tree.c b/fs/btrfs/root-tree.c
index 22124122728c..47733fb55df7 100644
--- a/fs/btrfs/root-tree.c
+++ b/fs/btrfs/root-tree.c
@@ -9,6 +9,8 @@
 #include "transaction.h"
 #include "disk-io.h"
 #include "print-tree.h"
+#include "qgroup.h"
+#include "space-info.h"
 
 /*
  * Read a root item from the tree. In case we detect a root item smaller then
@@ -497,3 +499,57 @@ void btrfs_update_root_times(struct btrfs_trans_handle *trans,
 	btrfs_set_stack_timespec_nsec(&item->ctime, ct.tv_nsec);
 	spin_unlock(&root->root_item_lock);
 }
+
+/*
+ * btrfs_subvolume_reserve_metadata() - reserve space for subvolume operation
+ * root: the root of the parent directory
+ * rsv: block reservation
+ * items: the number of items that we need do reservation
+ * use_global_rsv: allow fallback to the global block reservation
+ *
+ * This function is used to reserve the space for snapshot/subvolume
+ * creation and deletion. Those operations are different with the
+ * common file/directory operations, they change two fs/file trees
+ * and root tree, the number of items that the qgroup reserves is
+ * different with the free space reservation. So we can not use
+ * the space reservation mechanism in start_transaction().
+ */
+int btrfs_subvolume_reserve_metadata(struct btrfs_root *root,
+				     struct btrfs_block_rsv *rsv, int items,
+				     bool use_global_rsv)
+{
+	u64 qgroup_num_bytes = 0;
+	u64 num_bytes;
+	int ret;
+	struct btrfs_fs_info *fs_info = root->fs_info;
+	struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
+
+	if (test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags)) {
+		/* One for parent inode, two for dir entries */
+		qgroup_num_bytes = 3 * fs_info->nodesize;
+		ret = btrfs_qgroup_reserve_meta_prealloc(root,
+				qgroup_num_bytes, true);
+		if (ret)
+			return ret;
+	}
+
+	num_bytes = btrfs_calc_trans_metadata_size(fs_info, items);
+	rsv->space_info = btrfs_find_space_info(fs_info,
+					    BTRFS_BLOCK_GROUP_METADATA);
+	ret = btrfs_block_rsv_add(root, rsv, num_bytes,
+				  BTRFS_RESERVE_FLUSH_ALL);
+
+	if (ret == -ENOSPC && use_global_rsv)
+		ret = btrfs_block_rsv_migrate(global_rsv, rsv, num_bytes, true);
+
+	if (ret && qgroup_num_bytes)
+		btrfs_qgroup_free_meta_prealloc(root, qgroup_num_bytes);
+
+	return ret;
+}
+
+void btrfs_subvolume_release_metadata(struct btrfs_fs_info *fs_info,
+				      struct btrfs_block_rsv *rsv)
+{
+	btrfs_block_rsv_release(fs_info, rsv, (u64)-1);
+}
diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c
index f7b29f9db5e2..0c99cf9fb595 100644
--- a/fs/btrfs/scrub.c
+++ b/fs/btrfs/scrub.c
@@ -6,6 +6,7 @@
 #include <linux/blkdev.h>
 #include <linux/ratelimit.h>
 #include <linux/sched/mm.h>
+#include <crypto/hash.h>
 #include "ctree.h"
 #include "volumes.h"
 #include "disk-io.h"
@@ -1787,11 +1788,12 @@ static int scrub_checksum(struct scrub_block *sblock)
 static int scrub_checksum_data(struct scrub_block *sblock)
 {
 	struct scrub_ctx *sctx = sblock->sctx;
+	struct btrfs_fs_info *fs_info = sctx->fs_info;
+	SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
 	u8 csum[BTRFS_CSUM_SIZE];
 	u8 *on_disk_csum;
 	struct page *page;
 	void *buffer;
-	u32 crc = ~(u32)0;
 	u64 len;
 	int index;
 
@@ -1799,6 +1801,9 @@ static int scrub_checksum_data(struct scrub_block *sblock)
 	if (!sblock->pagev[0]->have_csum)
 		return 0;
 
+	shash->tfm = fs_info->csum_shash;
+	crypto_shash_init(shash);
+
 	on_disk_csum = sblock->pagev[0]->csum;
 	page = sblock->pagev[0]->page;
 	buffer = kmap_atomic(page);
@@ -1808,7 +1813,7 @@ static int scrub_checksum_data(struct scrub_block *sblock)
 	for (;;) {
 		u64 l = min_t(u64, len, PAGE_SIZE);
 
-		crc = btrfs_csum_data(buffer, crc, l);
+		crypto_shash_update(shash, buffer, l);
 		kunmap_atomic(buffer);
 		len -= l;
 		if (len == 0)
@@ -1820,7 +1825,7 @@ static int scrub_checksum_data(struct scrub_block *sblock)
 		buffer = kmap_atomic(page);
 	}
 
-	btrfs_csum_final(crc, csum);
+	crypto_shash_final(shash, csum);
 	if (memcmp(csum, on_disk_csum, sctx->csum_size))
 		sblock->checksum_error = 1;
 
@@ -1832,16 +1837,19 @@ static int scrub_checksum_tree_block(struct scrub_block *sblock)
 	struct scrub_ctx *sctx = sblock->sctx;
 	struct btrfs_header *h;
 	struct btrfs_fs_info *fs_info = sctx->fs_info;
+	SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
 	u8 calculated_csum[BTRFS_CSUM_SIZE];
 	u8 on_disk_csum[BTRFS_CSUM_SIZE];
 	struct page *page;
 	void *mapped_buffer;
 	u64 mapped_size;
 	void *p;
-	u32 crc = ~(u32)0;
 	u64 len;
 	int index;
 
+	shash->tfm = fs_info->csum_shash;
+	crypto_shash_init(shash);
+
 	BUG_ON(sblock->page_count < 1);
 	page = sblock->pagev[0]->page;
 	mapped_buffer = kmap_atomic(page);
@@ -1875,7 +1883,7 @@ static int scrub_checksum_tree_block(struct scrub_block *sblock)
 	for (;;) {
 		u64 l = min_t(u64, len, mapped_size);
 
-		crc = btrfs_csum_data(p, crc, l);
+		crypto_shash_update(shash, p, l);
 		kunmap_atomic(mapped_buffer);
 		len -= l;
 		if (len == 0)
@@ -1889,7 +1897,7 @@ static int scrub_checksum_tree_block(struct scrub_block *sblock)
 		p = mapped_buffer;
 	}
 
-	btrfs_csum_final(crc, calculated_csum);
+	crypto_shash_final(shash, calculated_csum);
 	if (memcmp(calculated_csum, on_disk_csum, sctx->csum_size))
 		sblock->checksum_error = 1;
 
@@ -1900,18 +1908,22 @@ static int scrub_checksum_super(struct scrub_block *sblock)
 {
 	struct btrfs_super_block *s;
 	struct scrub_ctx *sctx = sblock->sctx;
+	struct btrfs_fs_info *fs_info = sctx->fs_info;
+	SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
 	u8 calculated_csum[BTRFS_CSUM_SIZE];
 	u8 on_disk_csum[BTRFS_CSUM_SIZE];
 	struct page *page;
 	void *mapped_buffer;
 	u64 mapped_size;
 	void *p;
-	u32 crc = ~(u32)0;
 	int fail_gen = 0;
 	int fail_cor = 0;
 	u64 len;
 	int index;
 
+	shash->tfm = fs_info->csum_shash;
+	crypto_shash_init(shash);
+
 	BUG_ON(sblock->page_count < 1);
 	page = sblock->pagev[0]->page;
 	mapped_buffer = kmap_atomic(page);
@@ -1934,7 +1946,7 @@ static int scrub_checksum_super(struct scrub_block *sblock)
 	for (;;) {
 		u64 l = min_t(u64, len, mapped_size);
 
-		crc = btrfs_csum_data(p, crc, l);
+		crypto_shash_update(shash, p, l);
 		kunmap_atomic(mapped_buffer);
 		len -= l;
 		if (len == 0)
@@ -1948,7 +1960,7 @@ static int scrub_checksum_super(struct scrub_block *sblock)
 		p = mapped_buffer;
 	}
 
-	btrfs_csum_final(crc, calculated_csum);
+	crypto_shash_final(shash, calculated_csum);
 	if (memcmp(calculated_csum, on_disk_csum, sctx->csum_size))
 		++fail_cor;
 
@@ -2448,7 +2460,7 @@ static int scrub_find_csum(struct scrub_ctx *sctx, u64 logical, u8 *csum)
 	ASSERT(index < UINT_MAX);
 
 	num_sectors = sum->len / sctx->fs_info->sectorsize;
-	memcpy(csum, sum->sums + index, sctx->csum_size);
+	memcpy(csum, sum->sums + index * sctx->csum_size, sctx->csum_size);
 	if (index == num_sectors - 1) {
 		list_del(&sum->list);
 		kfree(sum);
@@ -2660,18 +2672,18 @@ static int get_raid56_logic_offset(u64 physical, int num,
 	u64 last_offset;
 	u32 stripe_index;
 	u32 rot;
+	const int data_stripes = nr_data_stripes(map);
 
-	last_offset = (physical - map->stripes[num].physical) *
-		      nr_data_stripes(map);
+	last_offset = (physical - map->stripes[num].physical) * data_stripes;
 	if (stripe_start)
 		*stripe_start = last_offset;
 
 	*offset = last_offset;
-	for (i = 0; i < nr_data_stripes(map); i++) {
+	for (i = 0; i < data_stripes; i++) {
 		*offset = last_offset + i * map->stripe_len;
 
 		stripe_nr = div64_u64(*offset, map->stripe_len);
-		stripe_nr = div_u64(stripe_nr, nr_data_stripes(map));
+		stripe_nr = div_u64(stripe_nr, data_stripes);
 
 		/* Work out the disk rotation on this stripe-set */
 		stripe_nr = div_u64_rem(stripe_nr, map->num_stripes, &rot);
@@ -3079,7 +3091,7 @@ static noinline_for_stack int scrub_stripe(struct scrub_ctx *sctx,
 		offset = map->stripe_len * (num / map->sub_stripes);
 		increment = map->stripe_len * factor;
 		mirror_num = num % map->sub_stripes + 1;
-	} else if (map->type & BTRFS_BLOCK_GROUP_RAID1) {
+	} else if (map->type & BTRFS_BLOCK_GROUP_RAID1_MASK) {
 		increment = map->stripe_len;
 		mirror_num = num % map->num_stripes + 1;
 	} else if (map->type & BTRFS_BLOCK_GROUP_DUP) {
@@ -3410,15 +3422,15 @@ static noinline_for_stack int scrub_chunk(struct scrub_ctx *sctx,
 					  struct btrfs_block_group_cache *cache)
 {
 	struct btrfs_fs_info *fs_info = sctx->fs_info;
-	struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree;
+	struct extent_map_tree *map_tree = &fs_info->mapping_tree;
 	struct map_lookup *map;
 	struct extent_map *em;
 	int i;
 	int ret = 0;
 
-	read_lock(&map_tree->map_tree.lock);
-	em = lookup_extent_mapping(&map_tree->map_tree, chunk_offset, 1);
-	read_unlock(&map_tree->map_tree.lock);
+	read_lock(&map_tree->lock);
+	em = lookup_extent_mapping(map_tree, chunk_offset, 1);
+	read_unlock(&map_tree->lock);
 
 	if (!em) {
 		/*
diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c
index f7fe4770f0e5..69b59bf75882 100644
--- a/fs/btrfs/send.c
+++ b/fs/btrfs/send.c
@@ -686,7 +686,7 @@ static int send_cmd(struct send_ctx *sctx)
 	hdr->len = cpu_to_le32(sctx->send_size - sizeof(*hdr));
 	hdr->crc = 0;
 
-	crc = crc32c(0, (unsigned char *)sctx->send_buf, sctx->send_size);
+	crc = btrfs_crc32c(0, (unsigned char *)sctx->send_buf, sctx->send_size);
 	hdr->crc = cpu_to_le32(crc);
 
 	ret = write_buf(sctx->send_filp, sctx->send_buf, sctx->send_size,
@@ -6929,9 +6929,23 @@ long btrfs_ioctl_send(struct file *mnt_file, struct btrfs_ioctl_send_args *arg)
 	if (ret)
 		goto out;
 
+	mutex_lock(&fs_info->balance_mutex);
+	if (test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) {
+		mutex_unlock(&fs_info->balance_mutex);
+		btrfs_warn_rl(fs_info,
+		"cannot run send because a balance operation is in progress");
+		ret = -EAGAIN;
+		goto out;
+	}
+	fs_info->send_in_progress++;
+	mutex_unlock(&fs_info->balance_mutex);
+
 	current->journal_info = BTRFS_SEND_TRANS_STUB;
 	ret = send_subvol(sctx);
 	current->journal_info = NULL;
+	mutex_lock(&fs_info->balance_mutex);
+	fs_info->send_in_progress--;
+	mutex_unlock(&fs_info->balance_mutex);
 	if (ret < 0)
 		goto out;
 
diff --git a/fs/btrfs/space-info.c b/fs/btrfs/space-info.c
new file mode 100644
index 000000000000..ab7b9ec4c240
--- /dev/null
+++ b/fs/btrfs/space-info.c
@@ -0,0 +1,1094 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include "ctree.h"
+#include "space-info.h"
+#include "sysfs.h"
+#include "volumes.h"
+#include "free-space-cache.h"
+#include "ordered-data.h"
+#include "transaction.h"
+#include "math.h"
+
+u64 btrfs_space_info_used(struct btrfs_space_info *s_info,
+			  bool may_use_included)
+{
+	ASSERT(s_info);
+	return s_info->bytes_used + s_info->bytes_reserved +
+		s_info->bytes_pinned + s_info->bytes_readonly +
+		(may_use_included ? s_info->bytes_may_use : 0);
+}
+
+/*
+ * after adding space to the filesystem, we need to clear the full flags
+ * on all the space infos.
+ */
+void btrfs_clear_space_info_full(struct btrfs_fs_info *info)
+{
+	struct list_head *head = &info->space_info;
+	struct btrfs_space_info *found;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(found, head, list)
+		found->full = 0;
+	rcu_read_unlock();
+}
+
+static const char *alloc_name(u64 flags)
+{
+	switch (flags) {
+	case BTRFS_BLOCK_GROUP_METADATA|BTRFS_BLOCK_GROUP_DATA:
+		return "mixed";
+	case BTRFS_BLOCK_GROUP_METADATA:
+		return "metadata";
+	case BTRFS_BLOCK_GROUP_DATA:
+		return "data";
+	case BTRFS_BLOCK_GROUP_SYSTEM:
+		return "system";
+	default:
+		WARN_ON(1);
+		return "invalid-combination";
+	};
+}
+
+static int create_space_info(struct btrfs_fs_info *info, u64 flags)
+{
+
+	struct btrfs_space_info *space_info;
+	int i;
+	int ret;
+
+	space_info = kzalloc(sizeof(*space_info), GFP_NOFS);
+	if (!space_info)
+		return -ENOMEM;
+
+	ret = percpu_counter_init(&space_info->total_bytes_pinned, 0,
+				 GFP_KERNEL);
+	if (ret) {
+		kfree(space_info);
+		return ret;
+	}
+
+	for (i = 0; i < BTRFS_NR_RAID_TYPES; i++)
+		INIT_LIST_HEAD(&space_info->block_groups[i]);
+	init_rwsem(&space_info->groups_sem);
+	spin_lock_init(&space_info->lock);
+	space_info->flags = flags & BTRFS_BLOCK_GROUP_TYPE_MASK;
+	space_info->force_alloc = CHUNK_ALLOC_NO_FORCE;
+	init_waitqueue_head(&space_info->wait);
+	INIT_LIST_HEAD(&space_info->ro_bgs);
+	INIT_LIST_HEAD(&space_info->tickets);
+	INIT_LIST_HEAD(&space_info->priority_tickets);
+
+	ret = kobject_init_and_add(&space_info->kobj, &space_info_ktype,
+				    info->space_info_kobj, "%s",
+				    alloc_name(space_info->flags));
+	if (ret) {
+		kobject_put(&space_info->kobj);
+		return ret;
+	}
+
+	list_add_rcu(&space_info->list, &info->space_info);
+	if (flags & BTRFS_BLOCK_GROUP_DATA)
+		info->data_sinfo = space_info;
+
+	return ret;
+}
+
+int btrfs_init_space_info(struct btrfs_fs_info *fs_info)
+{
+	struct btrfs_super_block *disk_super;
+	u64 features;
+	u64 flags;
+	int mixed = 0;
+	int ret;
+
+	disk_super = fs_info->super_copy;
+	if (!btrfs_super_root(disk_super))
+		return -EINVAL;
+
+	features = btrfs_super_incompat_flags(disk_super);
+	if (features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)
+		mixed = 1;
+
+	flags = BTRFS_BLOCK_GROUP_SYSTEM;
+	ret = create_space_info(fs_info, flags);
+	if (ret)
+		goto out;
+
+	if (mixed) {
+		flags = BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA;
+		ret = create_space_info(fs_info, flags);
+	} else {
+		flags = BTRFS_BLOCK_GROUP_METADATA;
+		ret = create_space_info(fs_info, flags);
+		if (ret)
+			goto out;
+
+		flags = BTRFS_BLOCK_GROUP_DATA;
+		ret = create_space_info(fs_info, flags);
+	}
+out:
+	return ret;
+}
+
+void btrfs_update_space_info(struct btrfs_fs_info *info, u64 flags,
+			     u64 total_bytes, u64 bytes_used,
+			     u64 bytes_readonly,
+			     struct btrfs_space_info **space_info)
+{
+	struct btrfs_space_info *found;
+	int factor;
+
+	factor = btrfs_bg_type_to_factor(flags);
+
+	found = btrfs_find_space_info(info, flags);
+	ASSERT(found);
+	spin_lock(&found->lock);
+	found->total_bytes += total_bytes;
+	found->disk_total += total_bytes * factor;
+	found->bytes_used += bytes_used;
+	found->disk_used += bytes_used * factor;
+	found->bytes_readonly += bytes_readonly;
+	if (total_bytes > 0)
+		found->full = 0;
+	btrfs_space_info_add_new_bytes(info, found,
+				       total_bytes - bytes_used -
+				       bytes_readonly);
+	spin_unlock(&found->lock);
+	*space_info = found;
+}
+
+struct btrfs_space_info *btrfs_find_space_info(struct btrfs_fs_info *info,
+					       u64 flags)
+{
+	struct list_head *head = &info->space_info;
+	struct btrfs_space_info *found;
+
+	flags &= BTRFS_BLOCK_GROUP_TYPE_MASK;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(found, head, list) {
+		if (found->flags & flags) {
+			rcu_read_unlock();
+			return found;
+		}
+	}
+	rcu_read_unlock();
+	return NULL;
+}
+
+static inline u64 calc_global_rsv_need_space(struct btrfs_block_rsv *global)
+{
+	return (global->size << 1);
+}
+
+static int can_overcommit(struct btrfs_fs_info *fs_info,
+			  struct btrfs_space_info *space_info, u64 bytes,
+			  enum btrfs_reserve_flush_enum flush,
+			  bool system_chunk)
+{
+	struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
+	u64 profile;
+	u64 space_size;
+	u64 avail;
+	u64 used;
+	int factor;
+
+	/* Don't overcommit when in mixed mode. */
+	if (space_info->flags & BTRFS_BLOCK_GROUP_DATA)
+		return 0;
+
+	if (system_chunk)
+		profile = btrfs_system_alloc_profile(fs_info);
+	else
+		profile = btrfs_metadata_alloc_profile(fs_info);
+
+	used = btrfs_space_info_used(space_info, false);
+
+	/*
+	 * We only want to allow over committing if we have lots of actual space
+	 * free, but if we don't have enough space to handle the global reserve
+	 * space then we could end up having a real enospc problem when trying
+	 * to allocate a chunk or some other such important allocation.
+	 */
+	spin_lock(&global_rsv->lock);
+	space_size = calc_global_rsv_need_space(global_rsv);
+	spin_unlock(&global_rsv->lock);
+	if (used + space_size >= space_info->total_bytes)
+		return 0;
+
+	used += space_info->bytes_may_use;
+
+	avail = atomic64_read(&fs_info->free_chunk_space);
+
+	/*
+	 * If we have dup, raid1 or raid10 then only half of the free
+	 * space is actually usable.  For raid56, the space info used
+	 * doesn't include the parity drive, so we don't have to
+	 * change the math
+	 */
+	factor = btrfs_bg_type_to_factor(profile);
+	avail = div_u64(avail, factor);
+
+	/*
+	 * If we aren't flushing all things, let us overcommit up to
+	 * 1/2th of the space. If we can flush, don't let us overcommit
+	 * too much, let it overcommit up to 1/8 of the space.
+	 */
+	if (flush == BTRFS_RESERVE_FLUSH_ALL)
+		avail >>= 3;
+	else
+		avail >>= 1;
+
+	if (used + bytes < space_info->total_bytes + avail)
+		return 1;
+	return 0;
+}
+
+/*
+ * This is for space we already have accounted in space_info->bytes_may_use, so
+ * basically when we're returning space from block_rsv's.
+ */
+void btrfs_space_info_add_old_bytes(struct btrfs_fs_info *fs_info,
+				    struct btrfs_space_info *space_info,
+				    u64 num_bytes)
+{
+	struct reserve_ticket *ticket;
+	struct list_head *head;
+	u64 used;
+	enum btrfs_reserve_flush_enum flush = BTRFS_RESERVE_NO_FLUSH;
+	bool check_overcommit = false;
+
+	spin_lock(&space_info->lock);
+	head = &space_info->priority_tickets;
+
+	/*
+	 * If we are over our limit then we need to check and see if we can
+	 * overcommit, and if we can't then we just need to free up our space
+	 * and not satisfy any requests.
+	 */
+	used = btrfs_space_info_used(space_info, true);
+	if (used - num_bytes >= space_info->total_bytes)
+		check_overcommit = true;
+again:
+	while (!list_empty(head) && num_bytes) {
+		ticket = list_first_entry(head, struct reserve_ticket,
+					  list);
+		/*
+		 * We use 0 bytes because this space is already reserved, so
+		 * adding the ticket space would be a double count.
+		 */
+		if (check_overcommit &&
+		    !can_overcommit(fs_info, space_info, 0, flush, false))
+			break;
+		if (num_bytes >= ticket->bytes) {
+			list_del_init(&ticket->list);
+			num_bytes -= ticket->bytes;
+			ticket->bytes = 0;
+			space_info->tickets_id++;
+			wake_up(&ticket->wait);
+		} else {
+			ticket->bytes -= num_bytes;
+			num_bytes = 0;
+		}
+	}
+
+	if (num_bytes && head == &space_info->priority_tickets) {
+		head = &space_info->tickets;
+		flush = BTRFS_RESERVE_FLUSH_ALL;
+		goto again;
+	}
+	btrfs_space_info_update_bytes_may_use(fs_info, space_info, -num_bytes);
+	trace_btrfs_space_reservation(fs_info, "space_info",
+				      space_info->flags, num_bytes, 0);
+	spin_unlock(&space_info->lock);
+}
+
+/*
+ * This is for newly allocated space that isn't accounted in
+ * space_info->bytes_may_use yet.  So if we allocate a chunk or unpin an extent
+ * we use this helper.
+ */
+void btrfs_space_info_add_new_bytes(struct btrfs_fs_info *fs_info,
+				    struct btrfs_space_info *space_info,
+				    u64 num_bytes)
+{
+	struct reserve_ticket *ticket;
+	struct list_head *head = &space_info->priority_tickets;
+
+again:
+	while (!list_empty(head) && num_bytes) {
+		ticket = list_first_entry(head, struct reserve_ticket,
+					  list);
+		if (num_bytes >= ticket->bytes) {
+			trace_btrfs_space_reservation(fs_info, "space_info",
+						      space_info->flags,
+						      ticket->bytes, 1);
+			list_del_init(&ticket->list);
+			num_bytes -= ticket->bytes;
+			btrfs_space_info_update_bytes_may_use(fs_info,
+							      space_info,
+							      ticket->bytes);
+			ticket->bytes = 0;
+			space_info->tickets_id++;
+			wake_up(&ticket->wait);
+		} else {
+			trace_btrfs_space_reservation(fs_info, "space_info",
+						      space_info->flags,
+						      num_bytes, 1);
+			btrfs_space_info_update_bytes_may_use(fs_info,
+							      space_info,
+							      num_bytes);
+			ticket->bytes -= num_bytes;
+			num_bytes = 0;
+		}
+	}
+
+	if (num_bytes && head == &space_info->priority_tickets) {
+		head = &space_info->tickets;
+		goto again;
+	}
+}
+
+#define DUMP_BLOCK_RSV(fs_info, rsv_name)				\
+do {									\
+	struct btrfs_block_rsv *__rsv = &(fs_info)->rsv_name;		\
+	spin_lock(&__rsv->lock);					\
+	btrfs_info(fs_info, #rsv_name ": size %llu reserved %llu",	\
+		   __rsv->size, __rsv->reserved);			\
+	spin_unlock(&__rsv->lock);					\
+} while (0)
+
+void btrfs_dump_space_info(struct btrfs_fs_info *fs_info,
+			   struct btrfs_space_info *info, u64 bytes,
+			   int dump_block_groups)
+{
+	struct btrfs_block_group_cache *cache;
+	int index = 0;
+
+	spin_lock(&info->lock);
+	btrfs_info(fs_info, "space_info %llu has %llu free, is %sfull",
+		   info->flags,
+		   info->total_bytes - btrfs_space_info_used(info, true),
+		   info->full ? "" : "not ");
+	btrfs_info(fs_info,
+		"space_info total=%llu, used=%llu, pinned=%llu, reserved=%llu, may_use=%llu, readonly=%llu",
+		info->total_bytes, info->bytes_used, info->bytes_pinned,
+		info->bytes_reserved, info->bytes_may_use,
+		info->bytes_readonly);
+	spin_unlock(&info->lock);
+
+	DUMP_BLOCK_RSV(fs_info, global_block_rsv);
+	DUMP_BLOCK_RSV(fs_info, trans_block_rsv);
+	DUMP_BLOCK_RSV(fs_info, chunk_block_rsv);
+	DUMP_BLOCK_RSV(fs_info, delayed_block_rsv);
+	DUMP_BLOCK_RSV(fs_info, delayed_refs_rsv);
+
+	if (!dump_block_groups)
+		return;
+
+	down_read(&info->groups_sem);
+again:
+	list_for_each_entry(cache, &info->block_groups[index], list) {
+		spin_lock(&cache->lock);
+		btrfs_info(fs_info,
+			"block group %llu has %llu bytes, %llu used %llu pinned %llu reserved %s",
+			cache->key.objectid, cache->key.offset,
+			btrfs_block_group_used(&cache->item), cache->pinned,
+			cache->reserved, cache->ro ? "[readonly]" : "");
+		btrfs_dump_free_space(cache, bytes);
+		spin_unlock(&cache->lock);
+	}
+	if (++index < BTRFS_NR_RAID_TYPES)
+		goto again;
+	up_read(&info->groups_sem);
+}
+
+static void btrfs_writeback_inodes_sb_nr(struct btrfs_fs_info *fs_info,
+					 unsigned long nr_pages, int nr_items)
+{
+	struct super_block *sb = fs_info->sb;
+
+	if (down_read_trylock(&sb->s_umount)) {
+		writeback_inodes_sb_nr(sb, nr_pages, WB_REASON_FS_FREE_SPACE);
+		up_read(&sb->s_umount);
+	} else {
+		/*
+		 * We needn't worry the filesystem going from r/w to r/o though
+		 * we don't acquire ->s_umount mutex, because the filesystem
+		 * should guarantee the delalloc inodes list be empty after
+		 * the filesystem is readonly(all dirty pages are written to
+		 * the disk).
+		 */
+		btrfs_start_delalloc_roots(fs_info, nr_items);
+		if (!current->journal_info)
+			btrfs_wait_ordered_roots(fs_info, nr_items, 0, (u64)-1);
+	}
+}
+
+static inline u64 calc_reclaim_items_nr(struct btrfs_fs_info *fs_info,
+					u64 to_reclaim)
+{
+	u64 bytes;
+	u64 nr;
+
+	bytes = btrfs_calc_trans_metadata_size(fs_info, 1);
+	nr = div64_u64(to_reclaim, bytes);
+	if (!nr)
+		nr = 1;
+	return nr;
+}
+
+#define EXTENT_SIZE_PER_ITEM	SZ_256K
+
+/*
+ * shrink metadata reservation for delalloc
+ */
+static void shrink_delalloc(struct btrfs_fs_info *fs_info, u64 to_reclaim,
+			    u64 orig, bool wait_ordered)
+{
+	struct btrfs_space_info *space_info;
+	struct btrfs_trans_handle *trans;
+	u64 delalloc_bytes;
+	u64 dio_bytes;
+	u64 async_pages;
+	u64 items;
+	long time_left;
+	unsigned long nr_pages;
+	int loops;
+
+	/* Calc the number of the pages we need flush for space reservation */
+	items = calc_reclaim_items_nr(fs_info, to_reclaim);
+	to_reclaim = items * EXTENT_SIZE_PER_ITEM;
+
+	trans = (struct btrfs_trans_handle *)current->journal_info;
+	space_info = btrfs_find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
+
+	delalloc_bytes = percpu_counter_sum_positive(
+						&fs_info->delalloc_bytes);
+	dio_bytes = percpu_counter_sum_positive(&fs_info->dio_bytes);
+	if (delalloc_bytes == 0 && dio_bytes == 0) {
+		if (trans)
+			return;
+		if (wait_ordered)
+			btrfs_wait_ordered_roots(fs_info, items, 0, (u64)-1);
+		return;
+	}
+
+	/*
+	 * If we are doing more ordered than delalloc we need to just wait on
+	 * ordered extents, otherwise we'll waste time trying to flush delalloc
+	 * that likely won't give us the space back we need.
+	 */
+	if (dio_bytes > delalloc_bytes)
+		wait_ordered = true;
+
+	loops = 0;
+	while ((delalloc_bytes || dio_bytes) && loops < 3) {
+		nr_pages = min(delalloc_bytes, to_reclaim) >> PAGE_SHIFT;
+
+		/*
+		 * Triggers inode writeback for up to nr_pages. This will invoke
+		 * ->writepages callback and trigger delalloc filling
+		 *  (btrfs_run_delalloc_range()).
+		 */
+		btrfs_writeback_inodes_sb_nr(fs_info, nr_pages, items);
+
+		/*
+		 * We need to wait for the compressed pages to start before
+		 * we continue.
+		 */
+		async_pages = atomic_read(&fs_info->async_delalloc_pages);
+		if (!async_pages)
+			goto skip_async;
+
+		/*
+		 * Calculate how many compressed pages we want to be written
+		 * before we continue. I.e if there are more async pages than we
+		 * require wait_event will wait until nr_pages are written.
+		 */
+		if (async_pages <= nr_pages)
+			async_pages = 0;
+		else
+			async_pages -= nr_pages;
+
+		wait_event(fs_info->async_submit_wait,
+			   atomic_read(&fs_info->async_delalloc_pages) <=
+			   (int)async_pages);
+skip_async:
+		spin_lock(&space_info->lock);
+		if (list_empty(&space_info->tickets) &&
+		    list_empty(&space_info->priority_tickets)) {
+			spin_unlock(&space_info->lock);
+			break;
+		}
+		spin_unlock(&space_info->lock);
+
+		loops++;
+		if (wait_ordered && !trans) {
+			btrfs_wait_ordered_roots(fs_info, items, 0, (u64)-1);
+		} else {
+			time_left = schedule_timeout_killable(1);
+			if (time_left)
+				break;
+		}
+		delalloc_bytes = percpu_counter_sum_positive(
+						&fs_info->delalloc_bytes);
+		dio_bytes = percpu_counter_sum_positive(&fs_info->dio_bytes);
+	}
+}
+
+/**
+ * maybe_commit_transaction - possibly commit the transaction if its ok to
+ * @root - the root we're allocating for
+ * @bytes - the number of bytes we want to reserve
+ * @force - force the commit
+ *
+ * This will check to make sure that committing the transaction will actually
+ * get us somewhere and then commit the transaction if it does.  Otherwise it
+ * will return -ENOSPC.
+ */
+static int may_commit_transaction(struct btrfs_fs_info *fs_info,
+				  struct btrfs_space_info *space_info)
+{
+	struct reserve_ticket *ticket = NULL;
+	struct btrfs_block_rsv *delayed_rsv = &fs_info->delayed_block_rsv;
+	struct btrfs_block_rsv *delayed_refs_rsv = &fs_info->delayed_refs_rsv;
+	struct btrfs_trans_handle *trans;
+	u64 bytes_needed;
+	u64 reclaim_bytes = 0;
+
+	trans = (struct btrfs_trans_handle *)current->journal_info;
+	if (trans)
+		return -EAGAIN;
+
+	spin_lock(&space_info->lock);
+	if (!list_empty(&space_info->priority_tickets))
+		ticket = list_first_entry(&space_info->priority_tickets,
+					  struct reserve_ticket, list);
+	else if (!list_empty(&space_info->tickets))
+		ticket = list_first_entry(&space_info->tickets,
+					  struct reserve_ticket, list);
+	bytes_needed = (ticket) ? ticket->bytes : 0;
+	spin_unlock(&space_info->lock);
+
+	if (!bytes_needed)
+		return 0;
+
+	trans = btrfs_join_transaction(fs_info->extent_root);
+	if (IS_ERR(trans))
+		return PTR_ERR(trans);
+
+	/*
+	 * See if there is enough pinned space to make this reservation, or if
+	 * we have block groups that are going to be freed, allowing us to
+	 * possibly do a chunk allocation the next loop through.
+	 */
+	if (test_bit(BTRFS_TRANS_HAVE_FREE_BGS, &trans->transaction->flags) ||
+	    __percpu_counter_compare(&space_info->total_bytes_pinned,
+				     bytes_needed,
+				     BTRFS_TOTAL_BYTES_PINNED_BATCH) >= 0)
+		goto commit;
+
+	/*
+	 * See if there is some space in the delayed insertion reservation for
+	 * this reservation.
+	 */
+	if (space_info != delayed_rsv->space_info)
+		goto enospc;
+
+	spin_lock(&delayed_rsv->lock);
+	reclaim_bytes += delayed_rsv->reserved;
+	spin_unlock(&delayed_rsv->lock);
+
+	spin_lock(&delayed_refs_rsv->lock);
+	reclaim_bytes += delayed_refs_rsv->reserved;
+	spin_unlock(&delayed_refs_rsv->lock);
+	if (reclaim_bytes >= bytes_needed)
+		goto commit;
+	bytes_needed -= reclaim_bytes;
+
+	if (__percpu_counter_compare(&space_info->total_bytes_pinned,
+				   bytes_needed,
+				   BTRFS_TOTAL_BYTES_PINNED_BATCH) < 0)
+		goto enospc;
+
+commit:
+	return btrfs_commit_transaction(trans);
+enospc:
+	btrfs_end_transaction(trans);
+	return -ENOSPC;
+}
+
+/*
+ * Try to flush some data based on policy set by @state. This is only advisory
+ * and may fail for various reasons. The caller is supposed to examine the
+ * state of @space_info to detect the outcome.
+ */
+static void flush_space(struct btrfs_fs_info *fs_info,
+		       struct btrfs_space_info *space_info, u64 num_bytes,
+		       int state)
+{
+	struct btrfs_root *root = fs_info->extent_root;
+	struct btrfs_trans_handle *trans;
+	int nr;
+	int ret = 0;
+
+	switch (state) {
+	case FLUSH_DELAYED_ITEMS_NR:
+	case FLUSH_DELAYED_ITEMS:
+		if (state == FLUSH_DELAYED_ITEMS_NR)
+			nr = calc_reclaim_items_nr(fs_info, num_bytes) * 2;
+		else
+			nr = -1;
+
+		trans = btrfs_join_transaction(root);
+		if (IS_ERR(trans)) {
+			ret = PTR_ERR(trans);
+			break;
+		}
+		ret = btrfs_run_delayed_items_nr(trans, nr);
+		btrfs_end_transaction(trans);
+		break;
+	case FLUSH_DELALLOC:
+	case FLUSH_DELALLOC_WAIT:
+		shrink_delalloc(fs_info, num_bytes * 2, num_bytes,
+				state == FLUSH_DELALLOC_WAIT);
+		break;
+	case FLUSH_DELAYED_REFS_NR:
+	case FLUSH_DELAYED_REFS:
+		trans = btrfs_join_transaction(root);
+		if (IS_ERR(trans)) {
+			ret = PTR_ERR(trans);
+			break;
+		}
+		if (state == FLUSH_DELAYED_REFS_NR)
+			nr = calc_reclaim_items_nr(fs_info, num_bytes);
+		else
+			nr = 0;
+		btrfs_run_delayed_refs(trans, nr);
+		btrfs_end_transaction(trans);
+		break;
+	case ALLOC_CHUNK:
+	case ALLOC_CHUNK_FORCE:
+		trans = btrfs_join_transaction(root);
+		if (IS_ERR(trans)) {
+			ret = PTR_ERR(trans);
+			break;
+		}
+		ret = btrfs_chunk_alloc(trans,
+				btrfs_metadata_alloc_profile(fs_info),
+				(state == ALLOC_CHUNK) ? CHUNK_ALLOC_NO_FORCE :
+					CHUNK_ALLOC_FORCE);
+		btrfs_end_transaction(trans);
+		if (ret > 0 || ret == -ENOSPC)
+			ret = 0;
+		break;
+	case COMMIT_TRANS:
+		/*
+		 * If we have pending delayed iputs then we could free up a
+		 * bunch of pinned space, so make sure we run the iputs before
+		 * we do our pinned bytes check below.
+		 */
+		btrfs_run_delayed_iputs(fs_info);
+		btrfs_wait_on_delayed_iputs(fs_info);
+
+		ret = may_commit_transaction(fs_info, space_info);
+		break;
+	default:
+		ret = -ENOSPC;
+		break;
+	}
+
+	trace_btrfs_flush_space(fs_info, space_info->flags, num_bytes, state,
+				ret);
+	return;
+}
+
+static inline u64
+btrfs_calc_reclaim_metadata_size(struct btrfs_fs_info *fs_info,
+				 struct btrfs_space_info *space_info,
+				 bool system_chunk)
+{
+	struct reserve_ticket *ticket;
+	u64 used;
+	u64 expected;
+	u64 to_reclaim = 0;
+
+	list_for_each_entry(ticket, &space_info->tickets, list)
+		to_reclaim += ticket->bytes;
+	list_for_each_entry(ticket, &space_info->priority_tickets, list)
+		to_reclaim += ticket->bytes;
+	if (to_reclaim)
+		return to_reclaim;
+
+	to_reclaim = min_t(u64, num_online_cpus() * SZ_1M, SZ_16M);
+	if (can_overcommit(fs_info, space_info, to_reclaim,
+			   BTRFS_RESERVE_FLUSH_ALL, system_chunk))
+		return 0;
+
+	used = btrfs_space_info_used(space_info, true);
+
+	if (can_overcommit(fs_info, space_info, SZ_1M,
+			   BTRFS_RESERVE_FLUSH_ALL, system_chunk))
+		expected = div_factor_fine(space_info->total_bytes, 95);
+	else
+		expected = div_factor_fine(space_info->total_bytes, 90);
+
+	if (used > expected)
+		to_reclaim = used - expected;
+	else
+		to_reclaim = 0;
+	to_reclaim = min(to_reclaim, space_info->bytes_may_use +
+				     space_info->bytes_reserved);
+	return to_reclaim;
+}
+
+static inline int need_do_async_reclaim(struct btrfs_fs_info *fs_info,
+					struct btrfs_space_info *space_info,
+					u64 used, bool system_chunk)
+{
+	u64 thresh = div_factor_fine(space_info->total_bytes, 98);
+
+	/* If we're just plain full then async reclaim just slows us down. */
+	if ((space_info->bytes_used + space_info->bytes_reserved) >= thresh)
+		return 0;
+
+	if (!btrfs_calc_reclaim_metadata_size(fs_info, space_info,
+					      system_chunk))
+		return 0;
+
+	return (used >= thresh && !btrfs_fs_closing(fs_info) &&
+		!test_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state));
+}
+
+static bool wake_all_tickets(struct list_head *head)
+{
+	struct reserve_ticket *ticket;
+
+	while (!list_empty(head)) {
+		ticket = list_first_entry(head, struct reserve_ticket, list);
+		list_del_init(&ticket->list);
+		ticket->error = -ENOSPC;
+		wake_up(&ticket->wait);
+		if (ticket->bytes != ticket->orig_bytes)
+			return true;
+	}
+	return false;
+}
+
+/*
+ * This is for normal flushers, we can wait all goddamned day if we want to.  We
+ * will loop and continuously try to flush as long as we are making progress.
+ * We count progress as clearing off tickets each time we have to loop.
+ */
+static void btrfs_async_reclaim_metadata_space(struct work_struct *work)
+{
+	struct btrfs_fs_info *fs_info;
+	struct btrfs_space_info *space_info;
+	u64 to_reclaim;
+	int flush_state;
+	int commit_cycles = 0;
+	u64 last_tickets_id;
+
+	fs_info = container_of(work, struct btrfs_fs_info, async_reclaim_work);
+	space_info = btrfs_find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
+
+	spin_lock(&space_info->lock);
+	to_reclaim = btrfs_calc_reclaim_metadata_size(fs_info, space_info,
+						      false);
+	if (!to_reclaim) {
+		space_info->flush = 0;
+		spin_unlock(&space_info->lock);
+		return;
+	}
+	last_tickets_id = space_info->tickets_id;
+	spin_unlock(&space_info->lock);
+
+	flush_state = FLUSH_DELAYED_ITEMS_NR;
+	do {
+		flush_space(fs_info, space_info, to_reclaim, flush_state);
+		spin_lock(&space_info->lock);
+		if (list_empty(&space_info->tickets)) {
+			space_info->flush = 0;
+			spin_unlock(&space_info->lock);
+			return;
+		}
+		to_reclaim = btrfs_calc_reclaim_metadata_size(fs_info,
+							      space_info,
+							      false);
+		if (last_tickets_id == space_info->tickets_id) {
+			flush_state++;
+		} else {
+			last_tickets_id = space_info->tickets_id;
+			flush_state = FLUSH_DELAYED_ITEMS_NR;
+			if (commit_cycles)
+				commit_cycles--;
+		}
+
+		/*
+		 * We don't want to force a chunk allocation until we've tried
+		 * pretty hard to reclaim space.  Think of the case where we
+		 * freed up a bunch of space and so have a lot of pinned space
+		 * to reclaim.  We would rather use that than possibly create a
+		 * underutilized metadata chunk.  So if this is our first run
+		 * through the flushing state machine skip ALLOC_CHUNK_FORCE and
+		 * commit the transaction.  If nothing has changed the next go
+		 * around then we can force a chunk allocation.
+		 */
+		if (flush_state == ALLOC_CHUNK_FORCE && !commit_cycles)
+			flush_state++;
+
+		if (flush_state > COMMIT_TRANS) {
+			commit_cycles++;
+			if (commit_cycles > 2) {
+				if (wake_all_tickets(&space_info->tickets)) {
+					flush_state = FLUSH_DELAYED_ITEMS_NR;
+					commit_cycles--;
+				} else {
+					space_info->flush = 0;
+				}
+			} else {
+				flush_state = FLUSH_DELAYED_ITEMS_NR;
+			}
+		}
+		spin_unlock(&space_info->lock);
+	} while (flush_state <= COMMIT_TRANS);
+}
+
+void btrfs_init_async_reclaim_work(struct work_struct *work)
+{
+	INIT_WORK(work, btrfs_async_reclaim_metadata_space);
+}
+
+static const enum btrfs_flush_state priority_flush_states[] = {
+	FLUSH_DELAYED_ITEMS_NR,
+	FLUSH_DELAYED_ITEMS,
+	ALLOC_CHUNK,
+};
+
+static void priority_reclaim_metadata_space(struct btrfs_fs_info *fs_info,
+					    struct btrfs_space_info *space_info,
+					    struct reserve_ticket *ticket)
+{
+	u64 to_reclaim;
+	int flush_state;
+
+	spin_lock(&space_info->lock);
+	to_reclaim = btrfs_calc_reclaim_metadata_size(fs_info, space_info,
+						      false);
+	if (!to_reclaim) {
+		spin_unlock(&space_info->lock);
+		return;
+	}
+	spin_unlock(&space_info->lock);
+
+	flush_state = 0;
+	do {
+		flush_space(fs_info, space_info, to_reclaim,
+			    priority_flush_states[flush_state]);
+		flush_state++;
+		spin_lock(&space_info->lock);
+		if (ticket->bytes == 0) {
+			spin_unlock(&space_info->lock);
+			return;
+		}
+		spin_unlock(&space_info->lock);
+	} while (flush_state < ARRAY_SIZE(priority_flush_states));
+}
+
+static int wait_reserve_ticket(struct btrfs_fs_info *fs_info,
+			       struct btrfs_space_info *space_info,
+			       struct reserve_ticket *ticket)
+
+{
+	DEFINE_WAIT(wait);
+	u64 reclaim_bytes = 0;
+	int ret = 0;
+
+	spin_lock(&space_info->lock);
+	while (ticket->bytes > 0 && ticket->error == 0) {
+		ret = prepare_to_wait_event(&ticket->wait, &wait, TASK_KILLABLE);
+		if (ret) {
+			ret = -EINTR;
+			break;
+		}
+		spin_unlock(&space_info->lock);
+
+		schedule();
+
+		finish_wait(&ticket->wait, &wait);
+		spin_lock(&space_info->lock);
+	}
+	if (!ret)
+		ret = ticket->error;
+	if (!list_empty(&ticket->list))
+		list_del_init(&ticket->list);
+	if (ticket->bytes && ticket->bytes < ticket->orig_bytes)
+		reclaim_bytes = ticket->orig_bytes - ticket->bytes;
+	spin_unlock(&space_info->lock);
+
+	if (reclaim_bytes)
+		btrfs_space_info_add_old_bytes(fs_info, space_info,
+					       reclaim_bytes);
+	return ret;
+}
+
+/**
+ * reserve_metadata_bytes - try to reserve bytes from the block_rsv's space
+ * @root - the root we're allocating for
+ * @space_info - the space info we want to allocate from
+ * @orig_bytes - the number of bytes we want
+ * @flush - whether or not we can flush to make our reservation
+ *
+ * This will reserve orig_bytes number of bytes from the space info associated
+ * with the block_rsv.  If there is not enough space it will make an attempt to
+ * flush out space to make room.  It will do this by flushing delalloc if
+ * possible or committing the transaction.  If flush is 0 then no attempts to
+ * regain reservations will be made and this will fail if there is not enough
+ * space already.
+ */
+static int __reserve_metadata_bytes(struct btrfs_fs_info *fs_info,
+				    struct btrfs_space_info *space_info,
+				    u64 orig_bytes,
+				    enum btrfs_reserve_flush_enum flush,
+				    bool system_chunk)
+{
+	struct reserve_ticket ticket;
+	u64 used;
+	u64 reclaim_bytes = 0;
+	int ret = 0;
+
+	ASSERT(orig_bytes);
+	ASSERT(!current->journal_info || flush != BTRFS_RESERVE_FLUSH_ALL);
+
+	spin_lock(&space_info->lock);
+	ret = -ENOSPC;
+	used = btrfs_space_info_used(space_info, true);
+
+	/*
+	 * Carry on if we have enough space (short-circuit) OR call
+	 * can_overcommit() to ensure we can overcommit to continue.
+	 */
+	if ((used + orig_bytes <= space_info->total_bytes) ||
+	    can_overcommit(fs_info, space_info, orig_bytes, flush,
+			   system_chunk)) {
+		btrfs_space_info_update_bytes_may_use(fs_info, space_info,
+						      orig_bytes);
+		trace_btrfs_space_reservation(fs_info, "space_info",
+					      space_info->flags, orig_bytes, 1);
+		ret = 0;
+	}
+
+	/*
+	 * If we couldn't make a reservation then setup our reservation ticket
+	 * and kick the async worker if it's not already running.
+	 *
+	 * If we are a priority flusher then we just need to add our ticket to
+	 * the list and we will do our own flushing further down.
+	 */
+	if (ret && flush != BTRFS_RESERVE_NO_FLUSH) {
+		ticket.orig_bytes = orig_bytes;
+		ticket.bytes = orig_bytes;
+		ticket.error = 0;
+		init_waitqueue_head(&ticket.wait);
+		if (flush == BTRFS_RESERVE_FLUSH_ALL) {
+			list_add_tail(&ticket.list, &space_info->tickets);
+			if (!space_info->flush) {
+				space_info->flush = 1;
+				trace_btrfs_trigger_flush(fs_info,
+							  space_info->flags,
+							  orig_bytes, flush,
+							  "enospc");
+				queue_work(system_unbound_wq,
+					   &fs_info->async_reclaim_work);
+			}
+		} else {
+			list_add_tail(&ticket.list,
+				      &space_info->priority_tickets);
+		}
+	} else if (!ret && space_info->flags & BTRFS_BLOCK_GROUP_METADATA) {
+		used += orig_bytes;
+		/*
+		 * We will do the space reservation dance during log replay,
+		 * which means we won't have fs_info->fs_root set, so don't do
+		 * the async reclaim as we will panic.
+		 */
+		if (!test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags) &&
+		    need_do_async_reclaim(fs_info, space_info,
+					  used, system_chunk) &&
+		    !work_busy(&fs_info->async_reclaim_work)) {
+			trace_btrfs_trigger_flush(fs_info, space_info->flags,
+						  orig_bytes, flush, "preempt");
+			queue_work(system_unbound_wq,
+				   &fs_info->async_reclaim_work);
+		}
+	}
+	spin_unlock(&space_info->lock);
+	if (!ret || flush == BTRFS_RESERVE_NO_FLUSH)
+		return ret;
+
+	if (flush == BTRFS_RESERVE_FLUSH_ALL)
+		return wait_reserve_ticket(fs_info, space_info, &ticket);
+
+	ret = 0;
+	priority_reclaim_metadata_space(fs_info, space_info, &ticket);
+	spin_lock(&space_info->lock);
+	if (ticket.bytes) {
+		if (ticket.bytes < orig_bytes)
+			reclaim_bytes = orig_bytes - ticket.bytes;
+		list_del_init(&ticket.list);
+		ret = -ENOSPC;
+	}
+	spin_unlock(&space_info->lock);
+
+	if (reclaim_bytes)
+		btrfs_space_info_add_old_bytes(fs_info, space_info,
+					       reclaim_bytes);
+	ASSERT(list_empty(&ticket.list));
+	return ret;
+}
+
+/**
+ * reserve_metadata_bytes - try to reserve bytes from the block_rsv's space
+ * @root - the root we're allocating for
+ * @block_rsv - the block_rsv we're allocating for
+ * @orig_bytes - the number of bytes we want
+ * @flush - whether or not we can flush to make our reservation
+ *
+ * This will reserve orig_bytes number of bytes from the space info associated
+ * with the block_rsv.  If there is not enough space it will make an attempt to
+ * flush out space to make room.  It will do this by flushing delalloc if
+ * possible or committing the transaction.  If flush is 0 then no attempts to
+ * regain reservations will be made and this will fail if there is not enough
+ * space already.
+ */
+int btrfs_reserve_metadata_bytes(struct btrfs_root *root,
+				 struct btrfs_block_rsv *block_rsv,
+				 u64 orig_bytes,
+				 enum btrfs_reserve_flush_enum flush)
+{
+	struct btrfs_fs_info *fs_info = root->fs_info;
+	struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
+	int ret;
+	bool system_chunk = (root == fs_info->chunk_root);
+
+	ret = __reserve_metadata_bytes(fs_info, block_rsv->space_info,
+				       orig_bytes, flush, system_chunk);
+	if (ret == -ENOSPC &&
+	    unlikely(root->orphan_cleanup_state == ORPHAN_CLEANUP_STARTED)) {
+		if (block_rsv != global_rsv &&
+		    !btrfs_block_rsv_use_bytes(global_rsv, orig_bytes))
+			ret = 0;
+	}
+	if (ret == -ENOSPC) {
+		trace_btrfs_space_reservation(fs_info, "space_info:enospc",
+					      block_rsv->space_info->flags,
+					      orig_bytes, 1);
+
+		if (btrfs_test_opt(fs_info, ENOSPC_DEBUG))
+			btrfs_dump_space_info(fs_info, block_rsv->space_info,
+					      orig_bytes, 0);
+	}
+	return ret;
+}
diff --git a/fs/btrfs/space-info.h b/fs/btrfs/space-info.h
new file mode 100644
index 000000000000..c2b54b8e1a14
--- /dev/null
+++ b/fs/btrfs/space-info.h
@@ -0,0 +1,133 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef BTRFS_SPACE_INFO_H
+#define BTRFS_SPACE_INFO_H
+
+struct btrfs_space_info {
+	spinlock_t lock;
+
+	u64 total_bytes;	/* total bytes in the space,
+				   this doesn't take mirrors into account */
+	u64 bytes_used;		/* total bytes used,
+				   this doesn't take mirrors into account */
+	u64 bytes_pinned;	/* total bytes pinned, will be freed when the
+				   transaction finishes */
+	u64 bytes_reserved;	/* total bytes the allocator has reserved for
+				   current allocations */
+	u64 bytes_may_use;	/* number of bytes that may be used for
+				   delalloc/allocations */
+	u64 bytes_readonly;	/* total bytes that are read only */
+
+	u64 max_extent_size;	/* This will hold the maximum extent size of
+				   the space info if we had an ENOSPC in the
+				   allocator. */
+
+	unsigned int full:1;	/* indicates that we cannot allocate any more
+				   chunks for this space */
+	unsigned int chunk_alloc:1;	/* set if we are allocating a chunk */
+
+	unsigned int flush:1;		/* set if we are trying to make space */
+
+	unsigned int force_alloc;	/* set if we need to force a chunk
+					   alloc for this space */
+
+	u64 disk_used;		/* total bytes used on disk */
+	u64 disk_total;		/* total bytes on disk, takes mirrors into
+				   account */
+
+	u64 flags;
+
+	/*
+	 * bytes_pinned is kept in line with what is actually pinned, as in
+	 * we've called update_block_group and dropped the bytes_used counter
+	 * and increased the bytes_pinned counter.  However this means that
+	 * bytes_pinned does not reflect the bytes that will be pinned once the
+	 * delayed refs are flushed, so this counter is inc'ed every time we
+	 * call btrfs_free_extent so it is a realtime count of what will be
+	 * freed once the transaction is committed.  It will be zeroed every
+	 * time the transaction commits.
+	 */
+	struct percpu_counter total_bytes_pinned;
+
+	struct list_head list;
+	/* Protected by the spinlock 'lock'. */
+	struct list_head ro_bgs;
+	struct list_head priority_tickets;
+	struct list_head tickets;
+	/*
+	 * tickets_id just indicates the next ticket will be handled, so note
+	 * it's not stored per ticket.
+	 */
+	u64 tickets_id;
+
+	struct rw_semaphore groups_sem;
+	/* for block groups in our same type */
+	struct list_head block_groups[BTRFS_NR_RAID_TYPES];
+	wait_queue_head_t wait;
+
+	struct kobject kobj;
+	struct kobject *block_group_kobjs[BTRFS_NR_RAID_TYPES];
+};
+
+struct reserve_ticket {
+	u64 orig_bytes;
+	u64 bytes;
+	int error;
+	struct list_head list;
+	wait_queue_head_t wait;
+};
+
+static inline bool btrfs_mixed_space_info(struct btrfs_space_info *space_info)
+{
+	return ((space_info->flags & BTRFS_BLOCK_GROUP_METADATA) &&
+		(space_info->flags & BTRFS_BLOCK_GROUP_DATA));
+}
+
+/*
+ *
+ * Declare a helper function to detect underflow of various space info members
+ */
+#define DECLARE_SPACE_INFO_UPDATE(name)					\
+static inline void							\
+btrfs_space_info_update_##name(struct btrfs_fs_info *fs_info,		\
+			       struct btrfs_space_info *sinfo,		\
+			       s64 bytes)				\
+{									\
+	lockdep_assert_held(&sinfo->lock);				\
+	trace_update_##name(fs_info, sinfo, sinfo->name, bytes);	\
+	if (bytes < 0 && sinfo->name < -bytes) {			\
+		WARN_ON(1);						\
+		sinfo->name = 0;					\
+		return;							\
+	}								\
+	sinfo->name += bytes;						\
+}
+
+DECLARE_SPACE_INFO_UPDATE(bytes_may_use);
+DECLARE_SPACE_INFO_UPDATE(bytes_pinned);
+
+void btrfs_space_info_add_new_bytes(struct btrfs_fs_info *fs_info,
+				    struct btrfs_space_info *space_info,
+				    u64 num_bytes);
+void btrfs_space_info_add_old_bytes(struct btrfs_fs_info *fs_info,
+				    struct btrfs_space_info *space_info,
+				    u64 num_bytes);
+int btrfs_init_space_info(struct btrfs_fs_info *fs_info);
+void btrfs_update_space_info(struct btrfs_fs_info *info, u64 flags,
+			     u64 total_bytes, u64 bytes_used,
+			     u64 bytes_readonly,
+			     struct btrfs_space_info **space_info);
+struct btrfs_space_info *btrfs_find_space_info(struct btrfs_fs_info *info,
+					       u64 flags);
+u64 btrfs_space_info_used(struct btrfs_space_info *s_info,
+			  bool may_use_included);
+void btrfs_clear_space_info_full(struct btrfs_fs_info *info);
+void btrfs_dump_space_info(struct btrfs_fs_info *fs_info,
+			   struct btrfs_space_info *info, u64 bytes,
+			   int dump_block_groups);
+int btrfs_reserve_metadata_bytes(struct btrfs_root *root,
+				 struct btrfs_block_rsv *block_rsv,
+				 u64 orig_bytes,
+				 enum btrfs_reserve_flush_enum flush);
+
+#endif /* BTRFS_SPACE_INFO_H */
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 0645ec428b4f..78de9d5d80c6 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -42,6 +42,7 @@
 #include "dev-replace.h"
 #include "free-space-cache.h"
 #include "backref.h"
+#include "space-info.h"
 #include "tests/btrfs-tests.h"
 
 #include "qgroup.h"
@@ -1553,6 +1554,8 @@ static struct dentry *btrfs_mount_root(struct file_system_type *fs_type,
 	} else {
 		snprintf(s->s_id, sizeof(s->s_id), "%pg", bdev);
 		btrfs_sb(s)->bdev_holder = fs_type;
+		if (!strstr(crc32c_impl(), "generic"))
+			set_bit(BTRFS_FS_CSUM_IMPL_FAST, &fs_info->flags);
 		error = btrfs_fill_super(s, fs_devices, data);
 	}
 	if (!error)
@@ -1601,14 +1604,10 @@ static struct dentry *btrfs_mount(struct file_system_type *fs_type, int flags,
 {
 	struct vfsmount *mnt_root;
 	struct dentry *root;
-	fmode_t mode = FMODE_READ;
 	char *subvol_name = NULL;
 	u64 subvol_objectid = 0;
 	int error = 0;
 
-	if (!(flags & SB_RDONLY))
-		mode |= FMODE_WRITE;
-
 	error = btrfs_parse_subvol_options(data, &subvol_name,
 					&subvol_objectid);
 	if (error) {
@@ -1904,8 +1903,9 @@ static inline int btrfs_calc_avail_data_space(struct btrfs_fs_info *fs_info,
 	u64 type;
 	u64 avail_space;
 	u64 min_stripe_size;
-	int min_stripes = 1, num_stripes = 1;
+	int min_stripes, num_stripes = 1;
 	int i = 0, nr_devices;
+	const struct btrfs_raid_attr *rattr;
 
 	/*
 	 * We aren't under the device list lock, so this is racy-ish, but good
@@ -1929,21 +1929,18 @@ static inline int btrfs_calc_avail_data_space(struct btrfs_fs_info *fs_info,
 
 	/* calc min stripe number for data space allocation */
 	type = btrfs_data_alloc_profile(fs_info);
-	if (type & BTRFS_BLOCK_GROUP_RAID0) {
-		min_stripes = 2;
+	rattr = &btrfs_raid_array[btrfs_bg_flags_to_raid_index(type)];
+	min_stripes = rattr->devs_min;
+
+	if (type & BTRFS_BLOCK_GROUP_RAID0)
 		num_stripes = nr_devices;
-	} else if (type & BTRFS_BLOCK_GROUP_RAID1) {
-		min_stripes = 2;
+	else if (type & BTRFS_BLOCK_GROUP_RAID1)
 		num_stripes = 2;
-	} else if (type & BTRFS_BLOCK_GROUP_RAID10) {
-		min_stripes = 4;
+	else if (type & BTRFS_BLOCK_GROUP_RAID10)
 		num_stripes = 4;
-	}
 
-	if (type & BTRFS_BLOCK_GROUP_DUP)
-		min_stripe_size = 2 * BTRFS_STRIPE_LEN;
-	else
-		min_stripe_size = BTRFS_STRIPE_LEN;
+	/* Adjust for more than 1 stripe per device */
+	min_stripe_size = rattr->dev_stripes * BTRFS_STRIPE_LEN;
 
 	rcu_read_lock();
 	list_for_each_entry_rcu(device, &fs_devices->devices, dev_list) {
@@ -2466,3 +2463,4 @@ late_initcall(init_btrfs_fs);
 module_exit(exit_btrfs_fs)
 
 MODULE_LICENSE("GPL");
+MODULE_SOFTDEP("pre: crc32c");
diff --git a/fs/btrfs/sysfs.c b/fs/btrfs/sysfs.c
index c1dfc97893ba..9539f8143b7a 100644
--- a/fs/btrfs/sysfs.c
+++ b/fs/btrfs/sysfs.c
@@ -16,6 +16,7 @@
 #include "transaction.h"
 #include "sysfs.h"
 #include "volumes.h"
+#include "space-info.h"
 
 static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj);
 static inline struct btrfs_fs_devices *to_fs_devs(struct kobject *kobj);
diff --git a/fs/btrfs/tests/extent-io-tests.c b/fs/btrfs/tests/extent-io-tests.c
index 7bf4d5734dbe..1bf6b5a79191 100644
--- a/fs/btrfs/tests/extent-io-tests.c
+++ b/fs/btrfs/tests/extent-io-tests.c
@@ -10,6 +10,7 @@
 #include "btrfs-tests.h"
 #include "../ctree.h"
 #include "../extent_io.h"
+#include "../btrfs_inode.h"
 
 #define PROCESS_UNLOCK		(1 << 0)
 #define PROCESS_RELEASE		(1 << 1)
@@ -58,7 +59,7 @@ static noinline int process_page_range(struct inode *inode, u64 start, u64 end,
 static int test_find_delalloc(u32 sectorsize)
 {
 	struct inode *inode;
-	struct extent_io_tree tmp;
+	struct extent_io_tree *tmp;
 	struct page *page;
 	struct page *locked_page = NULL;
 	unsigned long index = 0;
@@ -76,12 +77,13 @@ static int test_find_delalloc(u32 sectorsize)
 		test_std_err(TEST_ALLOC_INODE);
 		return -ENOMEM;
 	}
+	tmp = &BTRFS_I(inode)->io_tree;
 
 	/*
 	 * Passing NULL as we don't have fs_info but tracepoints are not used
 	 * at this point
 	 */
-	extent_io_tree_init(NULL, &tmp, IO_TREE_SELFTEST, NULL);
+	extent_io_tree_init(NULL, tmp, IO_TREE_SELFTEST, NULL);
 
 	/*
 	 * First go through and create and mark all of our pages dirty, we pin
@@ -108,10 +110,10 @@ static int test_find_delalloc(u32 sectorsize)
 	 * |--- delalloc ---|
 	 * |---  search  ---|
 	 */
-	set_extent_delalloc(&tmp, 0, sectorsize - 1, 0, NULL);
+	set_extent_delalloc(tmp, 0, sectorsize - 1, 0, NULL);
 	start = 0;
 	end = 0;
-	found = find_lock_delalloc_range(inode, &tmp, locked_page, &start,
+	found = find_lock_delalloc_range(inode, locked_page, &start,
 					 &end);
 	if (!found) {
 		test_err("should have found at least one delalloc");
@@ -122,7 +124,7 @@ static int test_find_delalloc(u32 sectorsize)
 			sectorsize - 1, start, end);
 		goto out_bits;
 	}
-	unlock_extent(&tmp, start, end);
+	unlock_extent(tmp, start, end);
 	unlock_page(locked_page);
 	put_page(locked_page);
 
@@ -139,10 +141,10 @@ static int test_find_delalloc(u32 sectorsize)
 		test_err("couldn't find the locked page");
 		goto out_bits;
 	}
-	set_extent_delalloc(&tmp, sectorsize, max_bytes - 1, 0, NULL);
+	set_extent_delalloc(tmp, sectorsize, max_bytes - 1, 0, NULL);
 	start = test_start;
 	end = 0;
-	found = find_lock_delalloc_range(inode, &tmp, locked_page, &start,
+	found = find_lock_delalloc_range(inode, locked_page, &start,
 					 &end);
 	if (!found) {
 		test_err("couldn't find delalloc in our range");
@@ -158,7 +160,7 @@ static int test_find_delalloc(u32 sectorsize)
 		test_err("there were unlocked pages in the range");
 		goto out_bits;
 	}
-	unlock_extent(&tmp, start, end);
+	unlock_extent(tmp, start, end);
 	/* locked_page was unlocked above */
 	put_page(locked_page);
 
@@ -176,7 +178,7 @@ static int test_find_delalloc(u32 sectorsize)
 	}
 	start = test_start;
 	end = 0;
-	found = find_lock_delalloc_range(inode, &tmp, locked_page, &start,
+	found = find_lock_delalloc_range(inode, locked_page, &start,
 					 &end);
 	if (found) {
 		test_err("found range when we shouldn't have");
@@ -194,10 +196,10 @@ static int test_find_delalloc(u32 sectorsize)
 	 *
 	 * We are re-using our test_start from above since it works out well.
 	 */
-	set_extent_delalloc(&tmp, max_bytes, total_dirty - 1, 0, NULL);
+	set_extent_delalloc(tmp, max_bytes, total_dirty - 1, 0, NULL);
 	start = test_start;
 	end = 0;
-	found = find_lock_delalloc_range(inode, &tmp, locked_page, &start,
+	found = find_lock_delalloc_range(inode, locked_page, &start,
 					 &end);
 	if (!found) {
 		test_err("didn't find our range");
@@ -213,7 +215,7 @@ static int test_find_delalloc(u32 sectorsize)
 		test_err("pages in range were not all locked");
 		goto out_bits;
 	}
-	unlock_extent(&tmp, start, end);
+	unlock_extent(tmp, start, end);
 
 	/*
 	 * Now to test where we run into a page that is no longer dirty in the
@@ -238,7 +240,7 @@ static int test_find_delalloc(u32 sectorsize)
 	 * this changes at any point in the future we will need to fix this
 	 * tests expected behavior.
 	 */
-	found = find_lock_delalloc_range(inode, &tmp, locked_page, &start,
+	found = find_lock_delalloc_range(inode, locked_page, &start,
 					 &end);
 	if (!found) {
 		test_err("didn't find our range");
@@ -256,7 +258,7 @@ static int test_find_delalloc(u32 sectorsize)
 	}
 	ret = 0;
 out_bits:
-	clear_extent_bits(&tmp, 0, total_dirty - 1, (unsigned)-1);
+	clear_extent_bits(tmp, 0, total_dirty - 1, (unsigned)-1);
 out:
 	if (locked_page)
 		put_page(locked_page);
@@ -432,6 +434,89 @@ out:
 	return ret;
 }
 
+static int test_find_first_clear_extent_bit(void)
+{
+	struct extent_io_tree tree;
+	u64 start, end;
+
+	test_msg("running find_first_clear_extent_bit test");
+	extent_io_tree_init(NULL, &tree, IO_TREE_SELFTEST, NULL);
+
+	/*
+	 * Set 1M-4M alloc/discard and 32M-64M thus leaving a hole between
+	 * 4M-32M
+	 */
+	set_extent_bits(&tree, SZ_1M, SZ_4M - 1,
+			CHUNK_TRIMMED | CHUNK_ALLOCATED);
+
+	find_first_clear_extent_bit(&tree, SZ_512K, &start, &end,
+				    CHUNK_TRIMMED | CHUNK_ALLOCATED);
+
+	if (start != 0 || end != SZ_1M -1)
+		test_err("error finding beginning range: start %llu end %llu",
+			 start, end);
+
+	/* Now add 32M-64M so that we have a hole between 4M-32M */
+	set_extent_bits(&tree, SZ_32M, SZ_64M - 1,
+			CHUNK_TRIMMED | CHUNK_ALLOCATED);
+
+	/*
+	 * Request first hole starting at 12M, we should get 4M-32M
+	 */
+	find_first_clear_extent_bit(&tree, 12 * SZ_1M, &start, &end,
+				    CHUNK_TRIMMED | CHUNK_ALLOCATED);
+
+	if (start != SZ_4M || end != SZ_32M - 1)
+		test_err("error finding trimmed range: start %llu end %llu",
+			 start, end);
+
+	/*
+	 * Search in the middle of allocated range, should get the next one
+	 * available, which happens to be unallocated -> 4M-32M
+	 */
+	find_first_clear_extent_bit(&tree, SZ_2M, &start, &end,
+				    CHUNK_TRIMMED | CHUNK_ALLOCATED);
+
+	if (start != SZ_4M || end != SZ_32M -1)
+		test_err("error finding next unalloc range: start %llu end %llu",
+			 start, end);
+
+	/*
+	 * Set 64M-72M with CHUNK_ALLOC flag, then search for CHUNK_TRIMMED flag
+	 * being unset in this range, we should get the entry in range 64M-72M
+	 */
+	set_extent_bits(&tree, SZ_64M, SZ_64M + SZ_8M - 1, CHUNK_ALLOCATED);
+	find_first_clear_extent_bit(&tree, SZ_64M + SZ_1M, &start, &end,
+				    CHUNK_TRIMMED);
+
+	if (start != SZ_64M || end != SZ_64M + SZ_8M - 1)
+		test_err("error finding exact range: start %llu end %llu",
+			 start, end);
+
+	find_first_clear_extent_bit(&tree, SZ_64M - SZ_8M, &start, &end,
+				    CHUNK_TRIMMED);
+
+	/*
+	 * Search in the middle of set range whose immediate neighbour doesn't
+	 * have the bits set so it must be returned
+	 */
+	if (start != SZ_64M || end != SZ_64M + SZ_8M - 1)
+		test_err("error finding next alloc range: start %llu end %llu",
+			 start, end);
+
+	/*
+	 * Search beyond any known range, shall return after last known range
+	 * and end should be -1
+	 */
+	find_first_clear_extent_bit(&tree, -1, &start, &end, CHUNK_TRIMMED);
+	if (start != SZ_64M + SZ_8M || end != -1)
+		test_err(
+		"error handling beyond end of range search: start %llu end %llu",
+			start, end);
+
+	return 0;
+}
+
 int btrfs_test_extent_io(u32 sectorsize, u32 nodesize)
 {
 	int ret;
@@ -442,6 +527,10 @@ int btrfs_test_extent_io(u32 sectorsize, u32 nodesize)
 	if (ret)
 		goto out;
 
+	ret = test_find_first_clear_extent_bit();
+	if (ret)
+		goto out;
+
 	ret = test_eb_bitmaps(sectorsize, nodesize);
 out:
 	return ret;
diff --git a/fs/btrfs/tests/extent-map-tests.c b/fs/btrfs/tests/extent-map-tests.c
index 87aeabe9d610..4a7f796c9900 100644
--- a/fs/btrfs/tests/extent-map-tests.c
+++ b/fs/btrfs/tests/extent-map-tests.c
@@ -66,7 +66,9 @@ static int test_case_1(struct btrfs_fs_info *fs_info,
 	em->len = SZ_16K;
 	em->block_start = 0;
 	em->block_len = SZ_16K;
+	write_lock(&em_tree->lock);
 	ret = add_extent_mapping(em_tree, em, 0);
+	write_unlock(&em_tree->lock);
 	if (ret < 0) {
 		test_err("cannot add extent range [0, 16K)");
 		goto out;
@@ -85,7 +87,9 @@ static int test_case_1(struct btrfs_fs_info *fs_info,
 	em->len = SZ_4K;
 	em->block_start = SZ_32K; /* avoid merging */
 	em->block_len = SZ_4K;
+	write_lock(&em_tree->lock);
 	ret = add_extent_mapping(em_tree, em, 0);
+	write_unlock(&em_tree->lock);
 	if (ret < 0) {
 		test_err("cannot add extent range [16K, 20K)");
 		goto out;
@@ -104,7 +108,9 @@ static int test_case_1(struct btrfs_fs_info *fs_info,
 	em->len = len;
 	em->block_start = start;
 	em->block_len = len;
+	write_lock(&em_tree->lock);
 	ret = btrfs_add_extent_mapping(fs_info, em_tree, &em, em->start, em->len);
+	write_unlock(&em_tree->lock);
 	if (ret) {
 		test_err("case1 [%llu %llu]: ret %d", start, start + len, ret);
 		goto out;
@@ -148,7 +154,9 @@ static int test_case_2(struct btrfs_fs_info *fs_info,
 	em->len = SZ_1K;
 	em->block_start = EXTENT_MAP_INLINE;
 	em->block_len = (u64)-1;
+	write_lock(&em_tree->lock);
 	ret = add_extent_mapping(em_tree, em, 0);
+	write_unlock(&em_tree->lock);
 	if (ret < 0) {
 		test_err("cannot add extent range [0, 1K)");
 		goto out;
@@ -167,7 +175,9 @@ static int test_case_2(struct btrfs_fs_info *fs_info,
 	em->len = SZ_4K;
 	em->block_start = SZ_4K;
 	em->block_len = SZ_4K;
+	write_lock(&em_tree->lock);
 	ret = add_extent_mapping(em_tree, em, 0);
+	write_unlock(&em_tree->lock);
 	if (ret < 0) {
 		test_err("cannot add extent range [4K, 8K)");
 		goto out;
@@ -186,7 +196,9 @@ static int test_case_2(struct btrfs_fs_info *fs_info,
 	em->len = SZ_1K;
 	em->block_start = EXTENT_MAP_INLINE;
 	em->block_len = (u64)-1;
+	write_lock(&em_tree->lock);
 	ret = btrfs_add_extent_mapping(fs_info, em_tree, &em, em->start, em->len);
+	write_unlock(&em_tree->lock);
 	if (ret) {
 		test_err("case2 [0 1K]: ret %d", ret);
 		goto out;
@@ -225,7 +237,9 @@ static int __test_case_3(struct btrfs_fs_info *fs_info,
 	em->len = SZ_4K;
 	em->block_start = SZ_4K;
 	em->block_len = SZ_4K;
+	write_lock(&em_tree->lock);
 	ret = add_extent_mapping(em_tree, em, 0);
+	write_unlock(&em_tree->lock);
 	if (ret < 0) {
 		test_err("cannot add extent range [4K, 8K)");
 		goto out;
@@ -244,7 +258,9 @@ static int __test_case_3(struct btrfs_fs_info *fs_info,
 	em->len = SZ_16K;
 	em->block_start = 0;
 	em->block_len = SZ_16K;
+	write_lock(&em_tree->lock);
 	ret = btrfs_add_extent_mapping(fs_info, em_tree, &em, start, len);
+	write_unlock(&em_tree->lock);
 	if (ret) {
 		test_err("case3 [0x%llx 0x%llx): ret %d",
 			 start, start + len, ret);
@@ -320,7 +336,9 @@ static int __test_case_4(struct btrfs_fs_info *fs_info,
 	em->len = SZ_8K;
 	em->block_start = 0;
 	em->block_len = SZ_8K;
+	write_lock(&em_tree->lock);
 	ret = add_extent_mapping(em_tree, em, 0);
+	write_unlock(&em_tree->lock);
 	if (ret < 0) {
 		test_err("cannot add extent range [0, 8K)");
 		goto out;
@@ -339,7 +357,9 @@ static int __test_case_4(struct btrfs_fs_info *fs_info,
 	em->len = 24 * SZ_1K;
 	em->block_start = SZ_16K; /* avoid merging */
 	em->block_len = 24 * SZ_1K;
+	write_lock(&em_tree->lock);
 	ret = add_extent_mapping(em_tree, em, 0);
+	write_unlock(&em_tree->lock);
 	if (ret < 0) {
 		test_err("cannot add extent range [8K, 32K)");
 		goto out;
@@ -357,7 +377,9 @@ static int __test_case_4(struct btrfs_fs_info *fs_info,
 	em->len = SZ_32K;
 	em->block_start = 0;
 	em->block_len = SZ_32K;
+	write_lock(&em_tree->lock);
 	ret = btrfs_add_extent_mapping(fs_info, em_tree, &em, start, len);
+	write_unlock(&em_tree->lock);
 	if (ret) {
 		test_err("case4 [0x%llx 0x%llx): ret %d",
 			 start, len, ret);
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 3f6811cdf803..3b8ae1a8f02d 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -129,6 +129,24 @@ static inline int extwriter_counter_read(struct btrfs_transaction *trans)
 }
 
 /*
+ * To be called after all the new block groups attached to the transaction
+ * handle have been created (btrfs_create_pending_block_groups()).
+ */
+void btrfs_trans_release_chunk_metadata(struct btrfs_trans_handle *trans)
+{
+	struct btrfs_fs_info *fs_info = trans->fs_info;
+
+	if (!trans->chunk_bytes_reserved)
+		return;
+
+	WARN_ON_ONCE(!list_empty(&trans->new_bgs));
+
+	btrfs_block_rsv_release(fs_info, &fs_info->chunk_block_rsv,
+				trans->chunk_bytes_reserved);
+	trans->chunk_bytes_reserved = 0;
+}
+
+/*
  * either allocate a new transaction or hop into the existing one
  */
 static noinline int join_transaction(struct btrfs_fs_info *fs_info,
diff --git a/fs/btrfs/transaction.h b/fs/btrfs/transaction.h
index 78c446c222b7..527ea94b57d9 100644
--- a/fs/btrfs/transaction.h
+++ b/fs/btrfs/transaction.h
@@ -224,5 +224,6 @@ void btrfs_put_transaction(struct btrfs_transaction *transaction);
 void btrfs_apply_pending_changes(struct btrfs_fs_info *fs_info);
 void btrfs_add_dropped_root(struct btrfs_trans_handle *trans,
 			    struct btrfs_root *root);
+void btrfs_trans_release_chunk_metadata(struct btrfs_trans_handle *trans);
 
 #endif
diff --git a/fs/btrfs/tree-checker.c b/fs/btrfs/tree-checker.c
index 96fce4bef4e7..ccd5706199d7 100644
--- a/fs/btrfs/tree-checker.c
+++ b/fs/btrfs/tree-checker.c
@@ -132,6 +132,7 @@ static int check_extent_data_item(struct extent_buffer *leaf,
 	struct btrfs_file_extent_item *fi;
 	u32 sectorsize = fs_info->sectorsize;
 	u32 item_size = btrfs_item_size_nr(leaf, slot);
+	u64 extent_end;
 
 	if (!IS_ALIGNED(key->offset, sectorsize)) {
 		file_extent_err(leaf, slot,
@@ -207,6 +208,16 @@ static int check_extent_data_item(struct extent_buffer *leaf,
 	    CHECK_FE_ALIGNED(leaf, slot, fi, num_bytes, sectorsize))
 		return -EUCLEAN;
 
+	/* Catch extent end overflow */
+	if (check_add_overflow(btrfs_file_extent_num_bytes(leaf, fi),
+			       key->offset, &extent_end)) {
+		file_extent_err(leaf, slot,
+	"extent end overflow, have file offset %llu extent num bytes %llu",
+				key->offset,
+				btrfs_file_extent_num_bytes(leaf, fi));
+		return -EUCLEAN;
+	}
+
 	/*
 	 * Check that no two consecutive file extent items, in the same leaf,
 	 * present ranges that overlap each other.
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index 3fc8d854d7fb..6c8297bcfeb7 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -3323,6 +3323,30 @@ int btrfs_free_log_root_tree(struct btrfs_trans_handle *trans,
 }
 
 /*
+ * Check if an inode was logged in the current transaction. We can't always rely
+ * on an inode's logged_trans value, because it's an in-memory only field and
+ * therefore not persisted. This means that its value is lost if the inode gets
+ * evicted and loaded again from disk (in which case it has a value of 0, and
+ * certainly it is smaller then any possible transaction ID), when that happens
+ * the full_sync flag is set in the inode's runtime flags, so on that case we
+ * assume eviction happened and ignore the logged_trans value, assuming the
+ * worst case, that the inode was logged before in the current transaction.
+ */
+static bool inode_logged(struct btrfs_trans_handle *trans,
+			 struct btrfs_inode *inode)
+{
+	if (inode->logged_trans == trans->transid)
+		return true;
+
+	if (inode->last_trans == trans->transid &&
+	    test_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &inode->runtime_flags) &&
+	    !test_bit(BTRFS_FS_LOG_RECOVERING, &trans->fs_info->flags))
+		return true;
+
+	return false;
+}
+
+/*
  * If both a file and directory are logged, and unlinks or renames are
  * mixed in, we have a few interesting corners:
  *
@@ -3356,7 +3380,7 @@ int btrfs_del_dir_entries_in_log(struct btrfs_trans_handle *trans,
 	int bytes_del = 0;
 	u64 dir_ino = btrfs_ino(dir);
 
-	if (dir->logged_trans < trans->transid)
+	if (!inode_logged(trans, dir))
 		return 0;
 
 	ret = join_running_log_trans(root);
@@ -3460,7 +3484,7 @@ int btrfs_del_inode_ref_in_log(struct btrfs_trans_handle *trans,
 	u64 index;
 	int ret;
 
-	if (inode->logged_trans < trans->transid)
+	if (!inode_logged(trans, inode))
 		return 0;
 
 	ret = join_running_log_trans(root);
@@ -5420,9 +5444,19 @@ log_extents:
 		}
 	}
 
+	/*
+	 * Don't update last_log_commit if we logged that an inode exists after
+	 * it was loaded to memory (full_sync bit set).
+	 * This is to prevent data loss when we do a write to the inode, then
+	 * the inode gets evicted after all delalloc was flushed, then we log
+	 * it exists (due to a rename for example) and then fsync it. This last
+	 * fsync would do nothing (not logging the extents previously written).
+	 */
 	spin_lock(&inode->lock);
 	inode->logged_trans = trans->transid;
-	inode->last_log_commit = inode->last_sub_trans;
+	if (inode_only != LOG_INODE_EXISTS ||
+	    !test_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &inode->runtime_flags))
+		inode->last_log_commit = inode->last_sub_trans;
 	spin_unlock(&inode->lock);
 out_unlock:
 	mutex_unlock(&inode->log_mutex);
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 1c2a6e4b39da..a13ddba1ebc3 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -28,6 +28,7 @@
 #include "dev-replace.h"
 #include "sysfs.h"
 #include "tree-checker.h"
+#include "space-info.h"
 
 const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES] = {
 	[BTRFS_RAID_RAID10] = {
@@ -123,12 +124,14 @@ const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES] = {
 	},
 };
 
-const char *get_raid_name(enum btrfs_raid_types type)
+const char *btrfs_bg_type_to_raid_name(u64 flags)
 {
-	if (type >= BTRFS_NR_RAID_TYPES)
+	const int index = btrfs_bg_flags_to_raid_index(flags);
+
+	if (index >= BTRFS_NR_RAID_TYPES)
 		return NULL;
 
-	return btrfs_raid_array[type].raid_name;
+	return btrfs_raid_array[index].raid_name;
 }
 
 /*
@@ -237,7 +240,9 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info,
  * chunk_mutex
  * -----------
  * protects chunks, adding or removing during allocation, trim or when a new
- * device is added/removed
+ * device is added/removed. Additionally it also protects post_commit_list of
+ * individual devices, since they can be added to the transaction's
+ * post_commit_list only with chunk_mutex held.
  *
  * cleaner_mutex
  * -------------
@@ -1818,7 +1823,7 @@ static u64 find_next_chunk(struct btrfs_fs_info *fs_info)
 	struct rb_node *n;
 	u64 ret = 0;
 
-	em_tree = &fs_info->mapping_tree.map_tree;
+	em_tree = &fs_info->mapping_tree;
 	read_lock(&em_tree->lock);
 	n = rb_last(&em_tree->map.rb_root);
 	if (n) {
@@ -2941,7 +2946,7 @@ struct extent_map *btrfs_get_chunk_map(struct btrfs_fs_info *fs_info,
 	struct extent_map_tree *em_tree;
 	struct extent_map *em;
 
-	em_tree = &fs_info->mapping_tree.map_tree;
+	em_tree = &fs_info->mapping_tree;
 	read_lock(&em_tree->lock);
 	em = lookup_extent_mapping(em_tree, logical, length);
 	read_unlock(&em_tree->lock);
@@ -3474,6 +3479,18 @@ static int chunk_devid_filter(struct extent_buffer *leaf,
 	return 1;
 }
 
+static u64 calc_data_stripes(u64 type, int num_stripes)
+{
+	const int index = btrfs_bg_flags_to_raid_index(type);
+	const int ncopies = btrfs_raid_array[index].ncopies;
+	const int nparity = btrfs_raid_array[index].nparity;
+
+	if (nparity)
+		return num_stripes - nparity;
+	else
+		return num_stripes / ncopies;
+}
+
 /* [pstart, pend) */
 static int chunk_drange_filter(struct extent_buffer *leaf,
 			       struct btrfs_chunk *chunk,
@@ -3483,22 +3500,15 @@ static int chunk_drange_filter(struct extent_buffer *leaf,
 	int num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
 	u64 stripe_offset;
 	u64 stripe_length;
+	u64 type;
 	int factor;
 	int i;
 
 	if (!(bargs->flags & BTRFS_BALANCE_ARGS_DEVID))
 		return 0;
 
-	if (btrfs_chunk_type(leaf, chunk) & (BTRFS_BLOCK_GROUP_DUP |
-	     BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10)) {
-		factor = num_stripes / 2;
-	} else if (btrfs_chunk_type(leaf, chunk) & BTRFS_BLOCK_GROUP_RAID5) {
-		factor = num_stripes - 1;
-	} else if (btrfs_chunk_type(leaf, chunk) & BTRFS_BLOCK_GROUP_RAID6) {
-		factor = num_stripes - 2;
-	} else {
-		factor = num_stripes;
-	}
+	type = btrfs_chunk_type(leaf, chunk);
+	factor = calc_data_stripes(type, num_stripes);
 
 	for (i = 0; i < num_stripes; i++) {
 		stripe = btrfs_stripe_nr(chunk, i);
@@ -3921,11 +3931,9 @@ static void describe_balance_args(struct btrfs_balance_args *bargs, char *buf,
 		bp += ret;						\
 	} while (0)
 
-	if (flags & BTRFS_BALANCE_ARGS_CONVERT) {
-		int index = btrfs_bg_flags_to_raid_index(bargs->target);
-
-		CHECK_APPEND_1ARG("convert=%s,", get_raid_name(index));
-	}
+	if (flags & BTRFS_BALANCE_ARGS_CONVERT)
+		CHECK_APPEND_1ARG("convert=%s,",
+				  btrfs_bg_type_to_raid_name(bargs->target));
 
 	if (flags & BTRFS_BALANCE_ARGS_SOFT)
 		CHECK_APPEND_NOARG("soft,");
@@ -4047,6 +4055,7 @@ int btrfs_balance(struct btrfs_fs_info *fs_info,
 	u64 num_devices;
 	unsigned seq;
 	bool reducing_integrity;
+	int i;
 
 	if (btrfs_fs_closing(fs_info) ||
 	    atomic_read(&fs_info->balance_pause_req) ||
@@ -4076,48 +4085,43 @@ int btrfs_balance(struct btrfs_fs_info *fs_info,
 	}
 
 	num_devices = btrfs_num_devices(fs_info);
+	allowed = 0;
+	for (i = 0; i < ARRAY_SIZE(btrfs_raid_array); i++)
+		if (num_devices >= btrfs_raid_array[i].devs_min)
+			allowed |= btrfs_raid_array[i].bg_flag;
 
-	allowed = BTRFS_AVAIL_ALLOC_BIT_SINGLE | BTRFS_BLOCK_GROUP_DUP;
-	if (num_devices > 1)
-		allowed |= (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1);
-	if (num_devices > 2)
-		allowed |= BTRFS_BLOCK_GROUP_RAID5;
-	if (num_devices > 3)
-		allowed |= (BTRFS_BLOCK_GROUP_RAID10 |
-			    BTRFS_BLOCK_GROUP_RAID6);
 	if (validate_convert_profile(&bctl->data, allowed)) {
-		int index = btrfs_bg_flags_to_raid_index(bctl->data.target);
-
 		btrfs_err(fs_info,
 			  "balance: invalid convert data profile %s",
-			  get_raid_name(index));
+			  btrfs_bg_type_to_raid_name(bctl->data.target));
 		ret = -EINVAL;
 		goto out;
 	}
 	if (validate_convert_profile(&bctl->meta, allowed)) {
-		int index = btrfs_bg_flags_to_raid_index(bctl->meta.target);
-
 		btrfs_err(fs_info,
 			  "balance: invalid convert metadata profile %s",
-			  get_raid_name(index));
+			  btrfs_bg_type_to_raid_name(bctl->meta.target));
 		ret = -EINVAL;
 		goto out;
 	}
 	if (validate_convert_profile(&bctl->sys, allowed)) {
-		int index = btrfs_bg_flags_to_raid_index(bctl->sys.target);
-
 		btrfs_err(fs_info,
 			  "balance: invalid convert system profile %s",
-			  get_raid_name(index));
+			  btrfs_bg_type_to_raid_name(bctl->sys.target));
 		ret = -EINVAL;
 		goto out;
 	}
 
-	/* allow to reduce meta or sys integrity only if force set */
-	allowed = BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1 |
-			BTRFS_BLOCK_GROUP_RAID10 |
-			BTRFS_BLOCK_GROUP_RAID5 |
-			BTRFS_BLOCK_GROUP_RAID6;
+	/*
+	 * Allow to reduce metadata or system integrity only if force set for
+	 * profiles with redundancy (copies, parity)
+	 */
+	allowed = 0;
+	for (i = 0; i < ARRAY_SIZE(btrfs_raid_array); i++) {
+		if (btrfs_raid_array[i].ncopies >= 2 ||
+		    btrfs_raid_array[i].tolerated_failures >= 1)
+			allowed |= btrfs_raid_array[i].bg_flag;
+	}
 	do {
 		seq = read_seqbegin(&fs_info->profiles_lock);
 
@@ -4152,12 +4156,18 @@ int btrfs_balance(struct btrfs_fs_info *fs_info,
 
 	if (btrfs_get_num_tolerated_disk_barrier_failures(meta_target) <
 		btrfs_get_num_tolerated_disk_barrier_failures(data_target)) {
-		int meta_index = btrfs_bg_flags_to_raid_index(meta_target);
-		int data_index = btrfs_bg_flags_to_raid_index(data_target);
-
 		btrfs_warn(fs_info,
 	"balance: metadata profile %s has lower redundancy than data profile %s",
-			   get_raid_name(meta_index), get_raid_name(data_index));
+				btrfs_bg_type_to_raid_name(meta_target),
+				btrfs_bg_type_to_raid_name(data_target));
+	}
+
+	if (fs_info->send_in_progress) {
+		btrfs_warn_rl(fs_info,
+"cannot run balance while send operations are in progress (%d in progress)",
+			      fs_info->send_in_progress);
+		ret = -EAGAIN;
+		goto out;
 	}
 
 	ret = insert_balance_item(fs_info, bctl);
@@ -4949,6 +4959,8 @@ static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
 	sub_stripes = btrfs_raid_array[index].sub_stripes;
 	dev_stripes = btrfs_raid_array[index].dev_stripes;
 	devs_max = btrfs_raid_array[index].devs_max;
+	if (!devs_max)
+		devs_max = BTRFS_MAX_DEVS(info);
 	devs_min = btrfs_raid_array[index].devs_min;
 	devs_increment = btrfs_raid_array[index].devs_increment;
 	ncopies = btrfs_raid_array[index].ncopies;
@@ -4957,8 +4969,6 @@ static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
 	if (type & BTRFS_BLOCK_GROUP_DATA) {
 		max_stripe_size = SZ_1G;
 		max_chunk_size = BTRFS_MAX_DATA_CHUNK_SIZE;
-		if (!devs_max)
-			devs_max = BTRFS_MAX_DEVS(info);
 	} else if (type & BTRFS_BLOCK_GROUP_METADATA) {
 		/* for larger filesystems, use larger metadata chunks */
 		if (fs_devices->total_rw_bytes > 50ULL * SZ_1G)
@@ -4966,13 +4976,9 @@ static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
 		else
 			max_stripe_size = SZ_256M;
 		max_chunk_size = max_stripe_size;
-		if (!devs_max)
-			devs_max = BTRFS_MAX_DEVS(info);
 	} else if (type & BTRFS_BLOCK_GROUP_SYSTEM) {
 		max_stripe_size = SZ_32M;
 		max_chunk_size = 2 * max_stripe_size;
-		if (!devs_max)
-			devs_max = BTRFS_MAX_DEVS_SYS_CHUNK;
 	} else {
 		btrfs_err(info, "invalid chunk type 0x%llx requested",
 		       type);
@@ -5143,7 +5149,7 @@ static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
 	em->block_len = em->len;
 	em->orig_block_len = stripe_size;
 
-	em_tree = &info->mapping_tree.map_tree;
+	em_tree = &info->mapping_tree;
 	write_lock(&em_tree->lock);
 	ret = add_extent_mapping(em_tree, em, 0);
 	if (ret) {
@@ -5324,20 +5330,9 @@ static noinline int init_first_rw_device(struct btrfs_trans_handle *trans)
 
 static inline int btrfs_chunk_max_errors(struct map_lookup *map)
 {
-	int max_errors;
+	const int index = btrfs_bg_flags_to_raid_index(map->type);
 
-	if (map->type & (BTRFS_BLOCK_GROUP_RAID1 |
-			 BTRFS_BLOCK_GROUP_RAID10 |
-			 BTRFS_BLOCK_GROUP_RAID5 |
-			 BTRFS_BLOCK_GROUP_DUP)) {
-		max_errors = 1;
-	} else if (map->type & BTRFS_BLOCK_GROUP_RAID6) {
-		max_errors = 2;
-	} else {
-		max_errors = 0;
-	}
-
-	return max_errors;
+	return btrfs_raid_array[index].tolerated_failures;
 }
 
 int btrfs_chunk_readonly(struct btrfs_fs_info *fs_info, u64 chunk_offset)
@@ -5378,21 +5373,16 @@ end:
 	return readonly;
 }
 
-void btrfs_mapping_init(struct btrfs_mapping_tree *tree)
-{
-	extent_map_tree_init(&tree->map_tree);
-}
-
-void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree)
+void btrfs_mapping_tree_free(struct extent_map_tree *tree)
 {
 	struct extent_map *em;
 
 	while (1) {
-		write_lock(&tree->map_tree.lock);
-		em = lookup_extent_mapping(&tree->map_tree, 0, (u64)-1);
+		write_lock(&tree->lock);
+		em = lookup_extent_mapping(tree, 0, (u64)-1);
 		if (em)
-			remove_extent_mapping(&tree->map_tree, em);
-		write_unlock(&tree->map_tree.lock);
+			remove_extent_mapping(tree, em);
+		write_unlock(&tree->lock);
 		if (!em)
 			break;
 		/* once for us */
@@ -5419,7 +5409,7 @@ int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len)
 		return 1;
 
 	map = em->map_lookup;
-	if (map->type & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1))
+	if (map->type & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1_MASK))
 		ret = map->num_stripes;
 	else if (map->type & BTRFS_BLOCK_GROUP_RAID10)
 		ret = map->sub_stripes;
@@ -5493,7 +5483,7 @@ static int find_live_mirror(struct btrfs_fs_info *fs_info,
 	struct btrfs_device *srcdev;
 
 	ASSERT((map->type &
-		 (BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10)));
+		 (BTRFS_BLOCK_GROUP_RAID1_MASK | BTRFS_BLOCK_GROUP_RAID10)));
 
 	if (map->type & BTRFS_BLOCK_GROUP_RAID10)
 		num_stripes = map->sub_stripes;
@@ -5682,7 +5672,7 @@ static int __btrfs_map_block_for_discard(struct btrfs_fs_info *fs_info,
 					      &remaining_stripes);
 		div_u64_rem(stripe_nr_end - 1, factor, &last_stripe);
 		last_stripe *= sub_stripes;
-	} else if (map->type & (BTRFS_BLOCK_GROUP_RAID1 |
+	} else if (map->type & (BTRFS_BLOCK_GROUP_RAID1_MASK |
 				BTRFS_BLOCK_GROUP_DUP)) {
 		num_stripes = map->num_stripes;
 	} else {
@@ -5926,6 +5916,102 @@ static bool need_full_stripe(enum btrfs_map_op op)
 	return (op == BTRFS_MAP_WRITE || op == BTRFS_MAP_GET_READ_MIRRORS);
 }
 
+/*
+ * btrfs_get_io_geometry - calculates the geomery of a particular (address, len)
+ *		       tuple. This information is used to calculate how big a
+ *		       particular bio can get before it straddles a stripe.
+ *
+ * @fs_info - the filesystem
+ * @logical - address that we want to figure out the geometry of
+ * @len	    - the length of IO we are going to perform, starting at @logical
+ * @op      - type of operation - write or read
+ * @io_geom - pointer used to return values
+ *
+ * Returns < 0 in case a chunk for the given logical address cannot be found,
+ * usually shouldn't happen unless @logical is corrupted, 0 otherwise.
+ */
+int btrfs_get_io_geometry(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
+			u64 logical, u64 len, struct btrfs_io_geometry *io_geom)
+{
+	struct extent_map *em;
+	struct map_lookup *map;
+	u64 offset;
+	u64 stripe_offset;
+	u64 stripe_nr;
+	u64 stripe_len;
+	u64 raid56_full_stripe_start = (u64)-1;
+	int data_stripes;
+
+	ASSERT(op != BTRFS_MAP_DISCARD);
+
+	em = btrfs_get_chunk_map(fs_info, logical, len);
+	if (IS_ERR(em))
+		return PTR_ERR(em);
+
+	map = em->map_lookup;
+	/* Offset of this logical address in the chunk */
+	offset = logical - em->start;
+	/* Len of a stripe in a chunk */
+	stripe_len = map->stripe_len;
+	/* Stripe wher this block falls in */
+	stripe_nr = div64_u64(offset, stripe_len);
+	/* Offset of stripe in the chunk */
+	stripe_offset = stripe_nr * stripe_len;
+	if (offset < stripe_offset) {
+		btrfs_crit(fs_info,
+"stripe math has gone wrong, stripe_offset=%llu offset=%llu start=%llu logical=%llu stripe_len=%llu",
+			stripe_offset, offset, em->start, logical, stripe_len);
+		free_extent_map(em);
+		return -EINVAL;
+	}
+
+	/* stripe_offset is the offset of this block in its stripe */
+	stripe_offset = offset - stripe_offset;
+	data_stripes = nr_data_stripes(map);
+
+	if (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
+		u64 max_len = stripe_len - stripe_offset;
+
+		/*
+		 * In case of raid56, we need to know the stripe aligned start
+		 */
+		if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
+			unsigned long full_stripe_len = stripe_len * data_stripes;
+			raid56_full_stripe_start = offset;
+
+			/*
+			 * Allow a write of a full stripe, but make sure we
+			 * don't allow straddling of stripes
+			 */
+			raid56_full_stripe_start = div64_u64(raid56_full_stripe_start,
+					full_stripe_len);
+			raid56_full_stripe_start *= full_stripe_len;
+
+			/*
+			 * For writes to RAID[56], allow a full stripeset across
+			 * all disks. For other RAID types and for RAID[56]
+			 * reads, just allow a single stripe (on a single disk).
+			 */
+			if (op == BTRFS_MAP_WRITE) {
+				max_len = stripe_len * data_stripes -
+					  (offset - raid56_full_stripe_start);
+			}
+		}
+		len = min_t(u64, em->len - offset, max_len);
+	} else {
+		len = em->len - offset;
+	}
+
+	io_geom->len = len;
+	io_geom->offset = offset;
+	io_geom->stripe_len = stripe_len;
+	io_geom->stripe_nr = stripe_nr;
+	io_geom->stripe_offset = stripe_offset;
+	io_geom->raid56_stripe_offset = raid56_full_stripe_start;
+
+	return 0;
+}
+
 static int __btrfs_map_block(struct btrfs_fs_info *fs_info,
 			     enum btrfs_map_op op,
 			     u64 logical, u64 *length,
@@ -5939,6 +6025,7 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info,
 	u64 stripe_nr;
 	u64 stripe_len;
 	u32 stripe_index;
+	int data_stripes;
 	int i;
 	int ret = 0;
 	int num_stripes;
@@ -5951,76 +6038,29 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info,
 	int patch_the_first_stripe_for_dev_replace = 0;
 	u64 physical_to_patch_in_first_stripe = 0;
 	u64 raid56_full_stripe_start = (u64)-1;
+	struct btrfs_io_geometry geom;
+
+	ASSERT(bbio_ret);
 
 	if (op == BTRFS_MAP_DISCARD)
 		return __btrfs_map_block_for_discard(fs_info, logical,
 						     *length, bbio_ret);
 
-	em = btrfs_get_chunk_map(fs_info, logical, *length);
-	if (IS_ERR(em))
-		return PTR_ERR(em);
+	ret = btrfs_get_io_geometry(fs_info, op, logical, *length, &geom);
+	if (ret < 0)
+		return ret;
 
+	em = btrfs_get_chunk_map(fs_info, logical, *length);
+	ASSERT(em);
 	map = em->map_lookup;
-	offset = logical - em->start;
-
-	stripe_len = map->stripe_len;
-	stripe_nr = offset;
-	/*
-	 * stripe_nr counts the total number of stripes we have to stride
-	 * to get to this block
-	 */
-	stripe_nr = div64_u64(stripe_nr, stripe_len);
-
-	stripe_offset = stripe_nr * stripe_len;
-	if (offset < stripe_offset) {
-		btrfs_crit(fs_info,
-			   "stripe math has gone wrong, stripe_offset=%llu, offset=%llu, start=%llu, logical=%llu, stripe_len=%llu",
-			   stripe_offset, offset, em->start, logical,
-			   stripe_len);
-		free_extent_map(em);
-		return -EINVAL;
-	}
-
-	/* stripe_offset is the offset of this block in its stripe*/
-	stripe_offset = offset - stripe_offset;
-
-	/* if we're here for raid56, we need to know the stripe aligned start */
-	if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
-		unsigned long full_stripe_len = stripe_len * nr_data_stripes(map);
-		raid56_full_stripe_start = offset;
 
-		/* allow a write of a full stripe, but make sure we don't
-		 * allow straddling of stripes
-		 */
-		raid56_full_stripe_start = div64_u64(raid56_full_stripe_start,
-				full_stripe_len);
-		raid56_full_stripe_start *= full_stripe_len;
-	}
-
-	if (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
-		u64 max_len;
-		/* For writes to RAID[56], allow a full stripeset across all disks.
-		   For other RAID types and for RAID[56] reads, just allow a single
-		   stripe (on a single disk). */
-		if ((map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) &&
-		    (op == BTRFS_MAP_WRITE)) {
-			max_len = stripe_len * nr_data_stripes(map) -
-				(offset - raid56_full_stripe_start);
-		} else {
-			/* we limit the length of each bio to what fits in a stripe */
-			max_len = stripe_len - stripe_offset;
-		}
-		*length = min_t(u64, em->len - offset, max_len);
-	} else {
-		*length = em->len - offset;
-	}
-
-	/*
-	 * This is for when we're called from btrfs_bio_fits_in_stripe and all
-	 * it cares about is the length
-	 */
-	if (!bbio_ret)
-		goto out;
+	*length = geom.len;
+	offset = geom.offset;
+	stripe_len = geom.stripe_len;
+	stripe_nr = geom.stripe_nr;
+	stripe_offset = geom.stripe_offset;
+	raid56_full_stripe_start = geom.raid56_stripe_offset;
+	data_stripes = nr_data_stripes(map);
 
 	down_read(&dev_replace->rwsem);
 	dev_replace_is_ongoing = btrfs_dev_replace_is_ongoing(dev_replace);
@@ -6052,7 +6092,7 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info,
 				&stripe_index);
 		if (!need_full_stripe(op))
 			mirror_num = 1;
-	} else if (map->type & BTRFS_BLOCK_GROUP_RAID1) {
+	} else if (map->type & BTRFS_BLOCK_GROUP_RAID1_MASK) {
 		if (need_full_stripe(op))
 			num_stripes = map->num_stripes;
 		else if (mirror_num)
@@ -6094,7 +6134,7 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info,
 		if (need_raid_map && (need_full_stripe(op) || mirror_num > 1)) {
 			/* push stripe_nr back to the start of the full stripe */
 			stripe_nr = div64_u64(raid56_full_stripe_start,
-					stripe_len * nr_data_stripes(map));
+					stripe_len * data_stripes);
 
 			/* RAID[56] write or recovery. Return all stripes */
 			num_stripes = map->num_stripes;
@@ -6110,10 +6150,9 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info,
 			 * Mirror #3 is RAID6 Q block.
 			 */
 			stripe_nr = div_u64_rem(stripe_nr,
-					nr_data_stripes(map), &stripe_index);
+					data_stripes, &stripe_index);
 			if (mirror_num > 1)
-				stripe_index = nr_data_stripes(map) +
-						mirror_num - 2;
+				stripe_index = data_stripes + mirror_num - 2;
 
 			/* We distribute the parity blocks across stripes */
 			div_u64_rem(stripe_nr + stripe_index, map->num_stripes,
@@ -6171,8 +6210,8 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info,
 		div_u64_rem(stripe_nr, num_stripes, &rot);
 
 		/* Fill in the logical address of each stripe */
-		tmp = stripe_nr * nr_data_stripes(map);
-		for (i = 0; i < nr_data_stripes(map); i++)
+		tmp = stripe_nr * data_stripes;
+		for (i = 0; i < data_stripes; i++)
 			bbio->raid_map[(i+rot) % num_stripes] =
 				em->start + (tmp + i) * map->stripe_len;
 
@@ -6687,7 +6726,7 @@ static int read_one_chunk(struct btrfs_key *key, struct extent_buffer *leaf,
 			  struct btrfs_chunk *chunk)
 {
 	struct btrfs_fs_info *fs_info = leaf->fs_info;
-	struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree;
+	struct extent_map_tree *map_tree = &fs_info->mapping_tree;
 	struct map_lookup *map;
 	struct extent_map *em;
 	u64 logical;
@@ -6712,9 +6751,9 @@ static int read_one_chunk(struct btrfs_key *key, struct extent_buffer *leaf,
 			return ret;
 	}
 
-	read_lock(&map_tree->map_tree.lock);
-	em = lookup_extent_mapping(&map_tree->map_tree, logical, 1);
-	read_unlock(&map_tree->map_tree.lock);
+	read_lock(&map_tree->lock);
+	em = lookup_extent_mapping(map_tree, logical, 1);
+	read_unlock(&map_tree->lock);
 
 	/* already mapped? */
 	if (em && em->start <= logical && em->start + em->len > logical) {
@@ -6783,9 +6822,9 @@ static int read_one_chunk(struct btrfs_key *key, struct extent_buffer *leaf,
 
 	}
 
-	write_lock(&map_tree->map_tree.lock);
-	ret = add_extent_mapping(&map_tree->map_tree, em, 0);
-	write_unlock(&map_tree->map_tree.lock);
+	write_lock(&map_tree->lock);
+	ret = add_extent_mapping(map_tree, em, 0);
+	write_unlock(&map_tree->lock);
 	if (ret < 0) {
 		btrfs_err(fs_info,
 			  "failed to add chunk map, start=%llu len=%llu: %d",
@@ -7103,14 +7142,14 @@ out_short_read:
 bool btrfs_check_rw_degradable(struct btrfs_fs_info *fs_info,
 					struct btrfs_device *failing_dev)
 {
-	struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree;
+	struct extent_map_tree *map_tree = &fs_info->mapping_tree;
 	struct extent_map *em;
 	u64 next_start = 0;
 	bool ret = true;
 
-	read_lock(&map_tree->map_tree.lock);
-	em = lookup_extent_mapping(&map_tree->map_tree, 0, (u64)-1);
-	read_unlock(&map_tree->map_tree.lock);
+	read_lock(&map_tree->lock);
+	em = lookup_extent_mapping(map_tree, 0, (u64)-1);
+	read_unlock(&map_tree->lock);
 	/* No chunk at all? Return false anyway */
 	if (!em) {
 		ret = false;
@@ -7148,10 +7187,10 @@ bool btrfs_check_rw_degradable(struct btrfs_fs_info *fs_info,
 		next_start = extent_map_end(em);
 		free_extent_map(em);
 
-		read_lock(&map_tree->map_tree.lock);
-		em = lookup_extent_mapping(&map_tree->map_tree, next_start,
+		read_lock(&map_tree->lock);
+		em = lookup_extent_mapping(map_tree, next_start,
 					   (u64)(-1) - next_start);
-		read_unlock(&map_tree->map_tree.lock);
+		read_unlock(&map_tree->lock);
 	}
 out:
 	return ret;
@@ -7600,10 +7639,9 @@ void btrfs_reset_fs_info_ptr(struct btrfs_fs_info *fs_info)
  */
 int btrfs_bg_type_to_factor(u64 flags)
 {
-	if (flags & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1 |
-		     BTRFS_BLOCK_GROUP_RAID10))
-		return 2;
-	return 1;
+	const int index = btrfs_bg_flags_to_raid_index(flags);
+
+	return btrfs_raid_array[index].ncopies;
 }
 
 
@@ -7612,7 +7650,7 @@ static int verify_one_dev_extent(struct btrfs_fs_info *fs_info,
 				 u64 chunk_offset, u64 devid,
 				 u64 physical_offset, u64 physical_len)
 {
-	struct extent_map_tree *em_tree = &fs_info->mapping_tree.map_tree;
+	struct extent_map_tree *em_tree = &fs_info->mapping_tree;
 	struct extent_map *em;
 	struct map_lookup *map;
 	struct btrfs_device *dev;
@@ -7701,7 +7739,7 @@ out:
 
 static int verify_chunk_dev_extent_mapping(struct btrfs_fs_info *fs_info)
 {
-	struct extent_map_tree *em_tree = &fs_info->mapping_tree.map_tree;
+	struct extent_map_tree *em_tree = &fs_info->mapping_tree;
 	struct extent_map *em;
 	struct rb_node *node;
 	int ret = 0;
diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
index 136a3eb64604..7f6aa1816409 100644
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -23,6 +23,21 @@ struct btrfs_pending_bios {
 	struct bio *tail;
 };
 
+struct btrfs_io_geometry {
+	/* remaining bytes before crossing a stripe */
+	u64 len;
+	/* offset of logical address in chunk */
+	u64 offset;
+	/* length of single IO stripe */
+	u64 stripe_len;
+	/* number of stripe where address falls */
+	u64 stripe_nr;
+	/* offset of address in stripe */
+	u64 stripe_offset;
+	/* offset of raid56 stripe into the chunk */
+	u64 raid56_stripe_offset;
+};
+
 /*
  * Use sequence counter to get consistent device stat data on
  * 32-bit processors.
@@ -43,8 +58,8 @@ struct btrfs_pending_bios {
 #define BTRFS_DEV_STATE_FLUSH_SENT	(4)
 
 struct btrfs_device {
-	struct list_head dev_list;
-	struct list_head dev_alloc_list;
+	struct list_head dev_list; /* device_list_mutex */
+	struct list_head dev_alloc_list; /* chunk mutex */
 	struct list_head post_commit_list; /* chunk mutex */
 	struct btrfs_fs_devices *fs_devices;
 	struct btrfs_fs_info *fs_info;
@@ -229,9 +244,14 @@ struct btrfs_fs_devices {
 	 * this mutex lock.
 	 */
 	struct mutex device_list_mutex;
+
+	/* List of all devices, protected by device_list_mutex */
 	struct list_head devices;
 
-	/* devices not currently being allocated */
+	/*
+	 * Devices which can satisfy space allocation. Protected by
+	 * chunk_mutex
+	 */
 	struct list_head alloc_list;
 
 	struct btrfs_fs_devices *seed;
@@ -336,16 +356,16 @@ struct btrfs_device_info {
 };
 
 struct btrfs_raid_attr {
-	int sub_stripes;	/* sub_stripes info for map */
-	int dev_stripes;	/* stripes per dev */
-	int devs_max;		/* max devs to use */
-	int devs_min;		/* min devs needed */
-	int tolerated_failures; /* max tolerated fail devs */
-	int devs_increment;	/* ndevs has to be a multiple of this */
-	int ncopies;		/* how many copies to data has */
-	int nparity;		/* number of stripes worth of bytes to store
+	u8 sub_stripes;		/* sub_stripes info for map */
+	u8 dev_stripes;		/* stripes per dev */
+	u8 devs_max;		/* max devs to use */
+	u8 devs_min;		/* min devs needed */
+	u8 tolerated_failures;	/* max tolerated fail devs */
+	u8 devs_increment;	/* ndevs has to be a multiple of this */
+	u8 ncopies;		/* how many copies to data has */
+	u8 nparity;		/* number of stripes worth of bytes to store
 				 * parity information */
-	int mindev_error;	/* error code if min devs requisite is unmet */
+	u8 mindev_error;	/* error code if min devs requisite is unmet */
 	const char raid_name[8]; /* name of the raid */
 	u64 bg_flag;		/* block group flag of the raid */
 };
@@ -408,13 +428,14 @@ int btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
 int btrfs_map_sblock(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
 		     u64 logical, u64 *length,
 		     struct btrfs_bio **bbio_ret);
+int btrfs_get_io_geometry(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
+		u64 logical, u64 len, struct btrfs_io_geometry *io_geom);
 int btrfs_rmap_block(struct btrfs_fs_info *fs_info, u64 chunk_start,
 		     u64 physical, u64 **logical, int *naddrs, int *stripe_len);
 int btrfs_read_sys_array(struct btrfs_fs_info *fs_info);
 int btrfs_read_chunk_tree(struct btrfs_fs_info *fs_info);
 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans, u64 type);
-void btrfs_mapping_init(struct btrfs_mapping_tree *tree);
-void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree);
+void btrfs_mapping_tree_free(struct extent_map_tree *tree);
 blk_status_t btrfs_map_bio(struct btrfs_fs_info *fs_info, struct bio *bio,
 			   int mirror_num, int async_submit);
 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
@@ -557,8 +578,6 @@ static inline enum btrfs_raid_types btrfs_bg_flags_to_raid_index(u64 flags)
 	return BTRFS_RAID_SINGLE; /* BTRFS_BLOCK_GROUP_SINGLE */
 }
 
-const char *get_raid_name(enum btrfs_raid_types type);
-
 void btrfs_commit_device_sizes(struct btrfs_transaction *trans);
 
 struct list_head *btrfs_get_fs_uuids(void);
@@ -568,6 +587,7 @@ bool btrfs_check_rw_degradable(struct btrfs_fs_info *fs_info,
 					struct btrfs_device *failing_dev);
 
 int btrfs_bg_type_to_factor(u64 flags);
+const char *btrfs_bg_type_to_raid_name(u64 flags);
 int btrfs_verify_dev_extents(struct btrfs_fs_info *fs_info);
 
 #endif