Merge tag 'for-5.20-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs updates from David Sterba:
 "This brings some long awaited changes, the send protocol bump,
  otherwise lots of small improvements and fixes. The main core part is
  reworking bio handling, cleaning up the submission and endio and
  improving error handling.

  There are some changes outside of btrfs adding helpers or updating
  API, listed at the end of the changelog.

  Features:

   - sysfs:
      - export chunk size, in debug mode add tunable for setting its size
      - show zoned among features (was only in debug mode)
      - show commit stats (number, last/max/total duration)

   - send protocol updated to 2
      - new commands:
         - ability write larger data chunks than 64K
         - send raw compressed extents (uses the encoded data ioctls),
           ie. no decompression on send side, no compression needed on
           receive side if supported
         - send 'otime' (inode creation time) among other timestamps
         - send file attributes (a.k.a file flags and xflags)
      - this is first version bump, backward compatibility on send and
        receive side is provided
      - there are still some known and wanted commands that will be
        implemented in the near future, another version bump will be
        needed, however we want to minimize that to avoid causing
        usability issues

   - print checksum type and implementation at mount time

   - don't print some messages at mount (mentioned as people asked about
     it), we want to print messages namely for new features so let's
     make some space for that
      - big metadata - this has been supported for a long time and is
        not a feature that's worth mentioning
      - skinny metadata - same reason, set by default by mkfs

  Performance improvements:

   - reduced amount of reserved metadata for delayed items
      - when inserted items can be batched into one leaf
      - when deleting batched directory index items
      - when deleting delayed items used for deletion
      - overall improved count of files/sec, decreased subvolume lock
        contention

   - metadata item access bounds checker micro-optimized, with a few
     percent of improved runtime for metadata-heavy operations

   - increase direct io limit for read to 256 sectors, improved
     throughput by 3x on sample workload

  Notable fixes:

   - raid56
      - reduce parity writes, skip sectors of stripe when there are no
        data updates
      - restore reading from on-disk data instead of using stripe cache,
        this reduces chances to damage correct data due to RMW cycle

   - refuse to replay log with unknown incompat read-only feature bit
     set

   - zoned
      - fix page locking when COW fails in the middle of allocation
      - improved tracking of active zones, ZNS drives may limit the
        number and there are ENOSPC errors due to that limit and not
        actual lack of space
      - adjust maximum extent size for zone append so it does not cause
        late ENOSPC due to underreservation

   - mirror reading error messages show the mirror number

   - don't fallback to buffered IO for NOWAIT direct IO writes, we don't
     have the NOWAIT semantics for buffered io yet

   - send, fix sending link commands for existing file paths when there
     are deleted and created hardlinks for same files

   - repair all mirrors for profiles with more than 1 copy (raid1c34)

   - fix repair of compressed extents, unify where error detection and
     repair happen

  Core changes:

   - bio completion cleanups
      - don't double defer compression bios
      - simplify endio workqueues
      - add more data to btrfs_bio to avoid allocation for read requests
      - rework bio error handling so it's same what block layer does,
        the submission works and errors are consumed in endio
      - when asynchronous bio offload fails fall back to synchronous
        checksum calculation to avoid errors under writeback or memory
        pressure

   - new trace points
      - raid56 events
      - ordered extent operations

   - super block log_root_transid deprecated (never used)

   - mixed_backref and big_metadata sysfs feature files removed, they've
     been default for sufficiently long time, there are no known users
     and mixed_backref could be confused with mixed_groups

  Non-btrfs changes, API updates:

   - minor highmem API update to cover const arguments

   - switch all kmap/kmap_atomic to kmap_local

   - remove redundant flush_dcache_page()

   - address_space_operations::writepage callback removed

   - add bdev_max_segments() helper"

* tag 'for-5.20-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (163 commits)
  btrfs: don't call btrfs_page_set_checked in finish_compressed_bio_read
  btrfs: fix repair of compressed extents
  btrfs: remove the start argument to check_data_csum and export
  btrfs: pass a btrfs_bio to btrfs_repair_one_sector
  btrfs: simplify the pending I/O counting in struct compressed_bio
  btrfs: repair all known bad mirrors
  btrfs: merge btrfs_dev_stat_print_on_error with its only caller
  btrfs: join running log transaction when logging new name
  btrfs: simplify error handling in btrfs_lookup_dentry
  btrfs: send: always use the rbtree based inode ref management infrastructure
  btrfs: send: fix sending link commands for existing file paths
  btrfs: send: introduce recorded_ref_alloc and recorded_ref_free
  btrfs: zoned: wait until zone is finished when allocation didn't progress
  btrfs: zoned: write out partially allocated region
  btrfs: zoned: activate necessary block group
  btrfs: zoned: activate metadata block group on flush_space
  btrfs: zoned: disable metadata overcommit for zoned
  btrfs: zoned: introduce space_info->active_total_bytes
  btrfs: zoned: finish least available block group on data bg allocation
  btrfs: let can_allocate_chunk return error
  ...

1 files changed, 151 insertions, 17 deletions

diff --git a/fs/btrfs/raid56.h b/fs/btrfs/raid56.h
index aaad08aefd7d..6f48f9e4c869 100644
--- a/fs/btrfs/raid56.h
+++ b/fs/btrfs/raid56.h
@@ -7,45 +7,179 @@
 #ifndef BTRFS_RAID56_H
 #define BTRFS_RAID56_H
 
-static inline int nr_parity_stripes(const struct map_lookup *map)
-{
-	if (map->type & BTRFS_BLOCK_GROUP_RAID5)
-		return 1;
-	else if (map->type & BTRFS_BLOCK_GROUP_RAID6)
-		return 2;
-	else
-		return 0;
-}
+#include <linux/workqueue.h>
+#include "volumes.h"
+
+enum btrfs_rbio_ops {
+	BTRFS_RBIO_WRITE,
+	BTRFS_RBIO_READ_REBUILD,
+	BTRFS_RBIO_PARITY_SCRUB,
+	BTRFS_RBIO_REBUILD_MISSING,
+};
+
+struct btrfs_raid_bio {
+	struct btrfs_io_context *bioc;
+
+	/*
+	 * While we're doing RMW on a stripe we put it into a hash table so we
+	 * can lock the stripe and merge more rbios into it.
+	 */
+	struct list_head hash_list;
+
+	/* LRU list for the stripe cache */
+	struct list_head stripe_cache;
+
+	/* For scheduling work in the helper threads */
+	struct work_struct work;
+
+	/*
+	 * bio_list and bio_list_lock are used to add more bios into the stripe
+	 * in hopes of avoiding the full RMW
+	 */
+	struct bio_list bio_list;
+	spinlock_t bio_list_lock;
+
+	/*
+	 * Also protected by the bio_list_lock, the plug list is used by the
+	 * plugging code to collect partial bios while plugged.  The stripe
+	 * locking code also uses it to hand off the stripe lock to the next
+	 * pending IO.
+	 */
+	struct list_head plug_list;
+
+	/* Flags that tell us if it is safe to merge with this bio. */
+	unsigned long flags;
+
+	/*
+	 * Set if we're doing a parity rebuild for a read from higher up, which
+	 * is handled differently from a parity rebuild as part of RMW.
+	 */
+	enum btrfs_rbio_ops operation;
+
+	/* How many pages there are for the full stripe including P/Q */
+	u16 nr_pages;
+
+	/* How many sectors there are for the full stripe including P/Q */
+	u16 nr_sectors;
+
+	/* Number of data stripes (no p/q) */
+	u8 nr_data;
+
+	/* Numer of all stripes (including P/Q) */
+	u8 real_stripes;
+
+	/* How many pages there are for each stripe */
+	u8 stripe_npages;
+
+	/* How many sectors there are for each stripe */
+	u8 stripe_nsectors;
+
+	/* First bad stripe, -1 means no corruption */
+	s8 faila;
+
+	/* Second bad stripe (for RAID6 use) */
+	s8 failb;
+
+	/* Stripe number that we're scrubbing  */
+	u8 scrubp;
+
+	/*
+	 * Size of all the bios in the bio_list.  This helps us decide if the
+	 * rbio maps to a full stripe or not.
+	 */
+	int bio_list_bytes;
+
+	int generic_bio_cnt;
+
+	refcount_t refs;
+
+	atomic_t stripes_pending;
+
+	atomic_t error;
+
+	struct work_struct end_io_work;
+
+	/* Bitmap to record which horizontal stripe has data */
+	unsigned long dbitmap;
+
+	/* Allocated with stripe_nsectors-many bits for finish_*() calls */
+	unsigned long finish_pbitmap;
+
+	/*
+	 * These are two arrays of pointers.  We allocate the rbio big enough
+	 * to hold them both and setup their locations when the rbio is
+	 * allocated.
+	 */
+
+	/*
+	 * Pointers to pages that we allocated for reading/writing stripes
+	 * directly from the disk (including P/Q).
+	 */
+	struct page **stripe_pages;
+
+	/* Pointers to the sectors in the bio_list, for faster lookup */
+	struct sector_ptr *bio_sectors;
+
+	/*
+	 * For subpage support, we need to map each sector to above
+	 * stripe_pages.
+	 */
+	struct sector_ptr *stripe_sectors;
+
+	/* Allocated with real_stripes-many pointers for finish_*() calls */
+	void **finish_pointers;
+};
+
+/*
+ * For trace event usage only. Records useful debug info for each bio submitted
+ * by RAID56 to each physical device.
+ *
+ * No matter signed or not, (-1) is always the one indicating we can not grab
+ * the proper stripe number.
+ */
+struct raid56_bio_trace_info {
+	u64 devid;
+
+	/* The offset inside the stripe. (<= STRIPE_LEN) */
+	u32 offset;
+
+	/*
+	 * Stripe number.
+	 * 0 is the first data stripe, and nr_data for P stripe,
+	 * nr_data + 1 for Q stripe.
+	 * >= real_stripes for
+	 */
+	u8 stripe_nr;
+};
 
 static inline int nr_data_stripes(const struct map_lookup *map)
 {
-	return map->num_stripes - nr_parity_stripes(map);
+	return map->num_stripes - btrfs_nr_parity_stripes(map->type);
 }
+
 #define RAID5_P_STRIPE ((u64)-2)
 #define RAID6_Q_STRIPE ((u64)-1)
 
 #define is_parity_stripe(x) (((x) == RAID5_P_STRIPE) ||		\
 			     ((x) == RAID6_Q_STRIPE))
 
-struct btrfs_raid_bio;
 struct btrfs_device;
 
-int raid56_parity_recover(struct bio *bio, struct btrfs_io_context *bioc,
-			  u32 stripe_len, int mirror_num, int generic_io);
-int raid56_parity_write(struct bio *bio, struct btrfs_io_context *bioc, u32 stripe_len);
+void raid56_parity_recover(struct bio *bio, struct btrfs_io_context *bioc,
+			   int mirror_num, bool generic_io);
+void raid56_parity_write(struct bio *bio, struct btrfs_io_context *bioc);
 
 void raid56_add_scrub_pages(struct btrfs_raid_bio *rbio, struct page *page,
 			    unsigned int pgoff, u64 logical);
 
 struct btrfs_raid_bio *raid56_parity_alloc_scrub_rbio(struct bio *bio,
-				struct btrfs_io_context *bioc, u32 stripe_len,
+				struct btrfs_io_context *bioc,
 				struct btrfs_device *scrub_dev,
 				unsigned long *dbitmap, int stripe_nsectors);
 void raid56_parity_submit_scrub_rbio(struct btrfs_raid_bio *rbio);
 
 struct btrfs_raid_bio *
-raid56_alloc_missing_rbio(struct bio *bio, struct btrfs_io_context *bioc,
-			  u64 length);
+raid56_alloc_missing_rbio(struct bio *bio, struct btrfs_io_context *bioc);
 void raid56_submit_missing_rbio(struct btrfs_raid_bio *rbio);
 
 int btrfs_alloc_stripe_hash_table(struct btrfs_fs_info *info);