diff options
Diffstat (limited to 'fs/f2fs/extent_cache.c')
| -rw-r--r-- | fs/f2fs/extent_cache.c | 791 |
1 files changed, 791 insertions, 0 deletions
diff --git a/fs/f2fs/extent_cache.c b/fs/f2fs/extent_cache.c new file mode 100644 index 000000000000..997ac86f2a1d --- /dev/null +++ b/fs/f2fs/extent_cache.c @@ -0,0 +1,791 @@ +/* + * f2fs extent cache support + * + * Copyright (c) 2015 Motorola Mobility + * Copyright (c) 2015 Samsung Electronics + * Authors: Jaegeuk Kim <jaegeuk@kernel.org> + * Chao Yu <chao2.yu@samsung.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/fs.h> +#include <linux/f2fs_fs.h> + +#include "f2fs.h" +#include "node.h" +#include <trace/events/f2fs.h> + +static struct kmem_cache *extent_tree_slab; +static struct kmem_cache *extent_node_slab; + +static struct extent_node *__attach_extent_node(struct f2fs_sb_info *sbi, + struct extent_tree *et, struct extent_info *ei, + struct rb_node *parent, struct rb_node **p) +{ + struct extent_node *en; + + en = kmem_cache_alloc(extent_node_slab, GFP_ATOMIC); + if (!en) + return NULL; + + en->ei = *ei; + INIT_LIST_HEAD(&en->list); + + rb_link_node(&en->rb_node, parent, p); + rb_insert_color(&en->rb_node, &et->root); + et->count++; + atomic_inc(&sbi->total_ext_node); + return en; +} + +static void __detach_extent_node(struct f2fs_sb_info *sbi, + struct extent_tree *et, struct extent_node *en) +{ + rb_erase(&en->rb_node, &et->root); + et->count--; + atomic_dec(&sbi->total_ext_node); + + if (et->cached_en == en) + et->cached_en = NULL; +} + +static struct extent_tree *__grab_extent_tree(struct inode *inode) +{ + struct f2fs_sb_info *sbi = F2FS_I_SB(inode); + struct extent_tree *et; + nid_t ino = inode->i_ino; + + down_write(&sbi->extent_tree_lock); + et = radix_tree_lookup(&sbi->extent_tree_root, ino); + if (!et) { + et = f2fs_kmem_cache_alloc(extent_tree_slab, GFP_NOFS); + f2fs_radix_tree_insert(&sbi->extent_tree_root, ino, et); + memset(et, 0, sizeof(struct extent_tree)); + et->ino = ino; + et->root = RB_ROOT; + et->cached_en = NULL; + rwlock_init(&et->lock); + atomic_set(&et->refcount, 0); + et->count = 0; + sbi->total_ext_tree++; + } + atomic_inc(&et->refcount); + up_write(&sbi->extent_tree_lock); + + /* never died until evict_inode */ + F2FS_I(inode)->extent_tree = et; + + return et; +} + +static struct extent_node *__lookup_extent_tree(struct f2fs_sb_info *sbi, + struct extent_tree *et, unsigned int fofs) +{ + struct rb_node *node = et->root.rb_node; + struct extent_node *en = et->cached_en; + + if (en) { + struct extent_info *cei = &en->ei; + + if (cei->fofs <= fofs && cei->fofs + cei->len > fofs) { + stat_inc_cached_node_hit(sbi); + return en; + } + } + + while (node) { + en = rb_entry(node, struct extent_node, rb_node); + + if (fofs < en->ei.fofs) { + node = node->rb_left; + } else if (fofs >= en->ei.fofs + en->ei.len) { + node = node->rb_right; + } else { + stat_inc_rbtree_node_hit(sbi); + return en; + } + } + return NULL; +} + +static struct extent_node *__init_extent_tree(struct f2fs_sb_info *sbi, + struct extent_tree *et, struct extent_info *ei) +{ + struct rb_node **p = &et->root.rb_node; + struct extent_node *en; + + en = __attach_extent_node(sbi, et, ei, NULL, p); + if (!en) + return NULL; + + et->largest = en->ei; + et->cached_en = en; + return en; +} + +static unsigned int __free_extent_tree(struct f2fs_sb_info *sbi, + struct extent_tree *et, bool free_all) +{ + struct rb_node *node, *next; + struct extent_node *en; + unsigned int count = et->count; + + node = rb_first(&et->root); + while (node) { + next = rb_next(node); + en = rb_entry(node, struct extent_node, rb_node); + + if (free_all) { + spin_lock(&sbi->extent_lock); + if (!list_empty(&en->list)) + list_del_init(&en->list); + spin_unlock(&sbi->extent_lock); + } + + if (free_all || list_empty(&en->list)) { + __detach_extent_node(sbi, et, en); + kmem_cache_free(extent_node_slab, en); + } + node = next; + } + + return count - et->count; +} + +static void __drop_largest_extent(struct inode *inode, pgoff_t fofs) +{ + struct extent_info *largest = &F2FS_I(inode)->extent_tree->largest; + + if (largest->fofs <= fofs && largest->fofs + largest->len > fofs) + largest->len = 0; +} + +void f2fs_drop_largest_extent(struct inode *inode, pgoff_t fofs) +{ + if (!f2fs_may_extent_tree(inode)) + return; + + __drop_largest_extent(inode, fofs); +} + +void f2fs_init_extent_tree(struct inode *inode, struct f2fs_extent *i_ext) +{ + struct f2fs_sb_info *sbi = F2FS_I_SB(inode); + struct extent_tree *et; + struct extent_node *en; + struct extent_info ei; + + if (!f2fs_may_extent_tree(inode)) + return; + + et = __grab_extent_tree(inode); + + if (!i_ext || le32_to_cpu(i_ext->len) < F2FS_MIN_EXTENT_LEN) + return; + + set_extent_info(&ei, le32_to_cpu(i_ext->fofs), + le32_to_cpu(i_ext->blk), le32_to_cpu(i_ext->len)); + + write_lock(&et->lock); + if (et->count) + goto out; + + en = __init_extent_tree(sbi, et, &ei); + if (en) { + spin_lock(&sbi->extent_lock); + list_add_tail(&en->list, &sbi->extent_list); + spin_unlock(&sbi->extent_lock); + } +out: + write_unlock(&et->lock); +} + +static bool f2fs_lookup_extent_tree(struct inode *inode, pgoff_t pgofs, + struct extent_info *ei) +{ + struct f2fs_sb_info *sbi = F2FS_I_SB(inode); + struct extent_tree *et = F2FS_I(inode)->extent_tree; + struct extent_node *en; + bool ret = false; + + f2fs_bug_on(sbi, !et); + + trace_f2fs_lookup_extent_tree_start(inode, pgofs); + + read_lock(&et->lock); + + if (et->largest.fofs <= pgofs && + et->largest.fofs + et->largest.len > pgofs) { + *ei = et->largest; + ret = true; + stat_inc_largest_node_hit(sbi); + goto out; + } + + en = __lookup_extent_tree(sbi, et, pgofs); + if (en) { + *ei = en->ei; + spin_lock(&sbi->extent_lock); + if (!list_empty(&en->list)) + list_move_tail(&en->list, &sbi->extent_list); + et->cached_en = en; + spin_unlock(&sbi->extent_lock); + ret = true; + } +out: + stat_inc_total_hit(sbi); + read_unlock(&et->lock); + + trace_f2fs_lookup_extent_tree_end(inode, pgofs, ei); + return ret; +} + + +/* + * lookup extent at @fofs, if hit, return the extent + * if not, return NULL and + * @prev_ex: extent before fofs + * @next_ex: extent after fofs + * @insert_p: insert point for new extent at fofs + * in order to simpfy the insertion after. + * tree must stay unchanged between lookup and insertion. + */ +static struct extent_node *__lookup_extent_tree_ret(struct extent_tree *et, + unsigned int fofs, + struct extent_node **prev_ex, + struct extent_node **next_ex, + struct rb_node ***insert_p, + struct rb_node **insert_parent) +{ + struct rb_node **pnode = &et->root.rb_node; + struct rb_node *parent = NULL, *tmp_node; + struct extent_node *en = et->cached_en; + + *insert_p = NULL; + *insert_parent = NULL; + *prev_ex = NULL; + *next_ex = NULL; + + if (RB_EMPTY_ROOT(&et->root)) + return NULL; + + if (en) { + struct extent_info *cei = &en->ei; + + if (cei->fofs <= fofs && cei->fofs + cei->len > fofs) + goto lookup_neighbors; + } + + while (*pnode) { + parent = *pnode; + en = rb_entry(*pnode, struct extent_node, rb_node); + + if (fofs < en->ei.fofs) + pnode = &(*pnode)->rb_left; + else if (fofs >= en->ei.fofs + en->ei.len) + pnode = &(*pnode)->rb_right; + else + goto lookup_neighbors; + } + + *insert_p = pnode; + *insert_parent = parent; + + en = rb_entry(parent, struct extent_node, rb_node); + tmp_node = parent; + if (parent && fofs > en->ei.fofs) + tmp_node = rb_next(parent); + *next_ex = tmp_node ? + rb_entry(tmp_node, struct extent_node, rb_node) : NULL; + + tmp_node = parent; + if (parent && fofs < en->ei.fofs) + tmp_node = rb_prev(parent); + *prev_ex = tmp_node ? + rb_entry(tmp_node, struct extent_node, rb_node) : NULL; + return NULL; + +lookup_neighbors: + if (fofs == en->ei.fofs) { + /* lookup prev node for merging backward later */ + tmp_node = rb_prev(&en->rb_node); + *prev_ex = tmp_node ? + rb_entry(tmp_node, struct extent_node, rb_node) : NULL; + } + if (fofs == en->ei.fofs + en->ei.len - 1) { + /* lookup next node for merging frontward later */ + tmp_node = rb_next(&en->rb_node); + *next_ex = tmp_node ? + rb_entry(tmp_node, struct extent_node, rb_node) : NULL; + } + return en; +} + +static struct extent_node *__try_merge_extent_node(struct f2fs_sb_info *sbi, + struct extent_tree *et, struct extent_info *ei, + struct extent_node **den, + struct extent_node *prev_ex, + struct extent_node *next_ex) +{ + struct extent_node *en = NULL; + + if (prev_ex && __is_back_mergeable(ei, &prev_ex->ei)) { + prev_ex->ei.len += ei->len; + ei = &prev_ex->ei; + en = prev_ex; + } + + if (next_ex && __is_front_mergeable(ei, &next_ex->ei)) { + if (en) { + __detach_extent_node(sbi, et, prev_ex); + *den = prev_ex; + } + next_ex->ei.fofs = ei->fofs; + next_ex->ei.blk = ei->blk; + next_ex->ei.len += ei->len; + en = next_ex; + } + + if (en) { + if (en->ei.len > et->largest.len) + et->largest = en->ei; + et->cached_en = en; + } + return en; +} + +static struct extent_node *__insert_extent_tree(struct f2fs_sb_info *sbi, + struct extent_tree *et, struct extent_info *ei, + struct rb_node **insert_p, + struct rb_node *insert_parent) +{ + struct rb_node **p = &et->root.rb_node; + struct rb_node *parent = NULL; + struct extent_node *en = NULL; + + if (insert_p && insert_parent) { + parent = insert_parent; + p = insert_p; + goto do_insert; + } + + while (*p) { + parent = *p; + en = rb_entry(parent, struct extent_node, rb_node); + + if (ei->fofs < en->ei.fofs) + p = &(*p)->rb_left; + else if (ei->fofs >= en->ei.fofs + en->ei.len) + p = &(*p)->rb_right; + else + f2fs_bug_on(sbi, 1); + } +do_insert: + en = __attach_extent_node(sbi, et, ei, parent, p); + if (!en) + return NULL; + + if (en->ei.len > et->largest.len) + et->largest = en->ei; + et->cached_en = en; + return en; +} + +unsigned int f2fs_update_extent_tree_range(struct inode *inode, + pgoff_t fofs, block_t blkaddr, unsigned int len) +{ + struct f2fs_sb_info *sbi = F2FS_I_SB(inode); + struct extent_tree *et = F2FS_I(inode)->extent_tree; + struct extent_node *en = NULL, *en1 = NULL, *en2 = NULL, *en3 = NULL; + struct extent_node *prev_en = NULL, *next_en = NULL; + struct extent_info ei, dei, prev; + struct rb_node **insert_p = NULL, *insert_parent = NULL; + unsigned int end = fofs + len; + unsigned int pos = (unsigned int)fofs; + + if (!et) + return false; + + write_lock(&et->lock); + + if (is_inode_flag_set(F2FS_I(inode), FI_NO_EXTENT)) { + write_unlock(&et->lock); + return false; + } + + prev = et->largest; + dei.len = 0; + + /* we do not guarantee that the largest extent is cached all the time */ + __drop_largest_extent(inode, fofs); + + /* 1. lookup first extent node in range [fofs, fofs + len - 1] */ + en = __lookup_extent_tree_ret(et, fofs, &prev_en, &next_en, + &insert_p, &insert_parent); + if (!en) { + if (next_en) { + en = next_en; + f2fs_bug_on(sbi, en->ei.fofs <= pos); + pos = en->ei.fofs; + } else { + /* + * skip searching in the tree since there is no + * larger extent node in the cache. + */ + goto update_extent; + } + } + + /* 2. invlidate all extent nodes in range [fofs, fofs + len - 1] */ + while (en) { + struct rb_node *node; + + if (pos >= end) + break; + + dei = en->ei; + en1 = en2 = NULL; + + node = rb_next(&en->rb_node); + + /* + * 2.1 there are four cases when we invalidate blkaddr in extent + * node, |V: valid address, X: will be invalidated| + */ + /* case#1, invalidate right part of extent node |VVVVVXXXXX| */ + if (pos > dei.fofs && end >= dei.fofs + dei.len) { + en->ei.len = pos - dei.fofs; + + if (en->ei.len < F2FS_MIN_EXTENT_LEN) { + __detach_extent_node(sbi, et, en); + insert_p = NULL; + insert_parent = NULL; + goto update; + } + + if (__is_extent_same(&dei, &et->largest)) + et->largest = en->ei; + goto next; + } + + /* case#2, invalidate left part of extent node |XXXXXVVVVV| */ + if (pos <= dei.fofs && end < dei.fofs + dei.len) { + en->ei.fofs = end; + en->ei.blk += end - dei.fofs; + en->ei.len -= end - dei.fofs; + + if (en->ei.len < F2FS_MIN_EXTENT_LEN) { + __detach_extent_node(sbi, et, en); + insert_p = NULL; + insert_parent = NULL; + goto update; + } + + if (__is_extent_same(&dei, &et->largest)) + et->largest = en->ei; + goto next; + } + + __detach_extent_node(sbi, et, en); + + /* + * if we remove node in rb-tree, our parent node pointer may + * point the wrong place, discard them. + */ + insert_p = NULL; + insert_parent = NULL; + + /* case#3, invalidate entire extent node |XXXXXXXXXX| */ + if (pos <= dei.fofs && end >= dei.fofs + dei.len) { + if (__is_extent_same(&dei, &et->largest)) + et->largest.len = 0; + goto update; + } + + /* + * case#4, invalidate data in the middle of extent node + * |VVVXXXXVVV| + */ + if (dei.len > F2FS_MIN_EXTENT_LEN) { + unsigned int endofs; + + /* insert left part of split extent into cache */ + if (pos - dei.fofs >= F2FS_MIN_EXTENT_LEN) { + set_extent_info(&ei, dei.fofs, dei.blk, + pos - dei.fofs); + en1 = __insert_extent_tree(sbi, et, &ei, + NULL, NULL); + } + + /* insert right part of split extent into cache */ + endofs = dei.fofs + dei.len; + if (endofs - end >= F2FS_MIN_EXTENT_LEN) { + set_extent_info(&ei, end, + end - dei.fofs + dei.blk, + endofs - end); + en2 = __insert_extent_tree(sbi, et, &ei, + NULL, NULL); + } + } +update: + /* 2.2 update in global extent list */ + spin_lock(&sbi->extent_lock); + if (en && !list_empty(&en->list)) + list_del(&en->list); + if (en1) + list_add_tail(&en1->list, &sbi->extent_list); + if (en2) + list_add_tail(&en2->list, &sbi->extent_list); + spin_unlock(&sbi->extent_lock); + + /* 2.3 release extent node */ + if (en) + kmem_cache_free(extent_node_slab, en); +next: + en = node ? rb_entry(node, struct extent_node, rb_node) : NULL; + next_en = en; + if (en) + pos = en->ei.fofs; + } + +update_extent: + /* 3. update extent in extent cache */ + if (blkaddr) { + struct extent_node *den = NULL; + + set_extent_info(&ei, fofs, blkaddr, len); + en3 = __try_merge_extent_node(sbi, et, &ei, &den, + prev_en, next_en); + if (!en3) + en3 = __insert_extent_tree(sbi, et, &ei, + insert_p, insert_parent); + + /* give up extent_cache, if split and small updates happen */ + if (dei.len >= 1 && + prev.len < F2FS_MIN_EXTENT_LEN && + et->largest.len < F2FS_MIN_EXTENT_LEN) { + et->largest.len = 0; + set_inode_flag(F2FS_I(inode), FI_NO_EXTENT); + } + + spin_lock(&sbi->extent_lock); + if (en3) { + if (list_empty(&en3->list)) + list_add_tail(&en3->list, &sbi->extent_list); + else + list_move_tail(&en3->list, &sbi->extent_list); + } + if (den && !list_empty(&den->list)) + list_del(&den->list); + spin_unlock(&sbi->extent_lock); + + if (den) + kmem_cache_free(extent_node_slab, den); + } + + if (is_inode_flag_set(F2FS_I(inode), FI_NO_EXTENT)) + __free_extent_tree(sbi, et, true); + + write_unlock(&et->lock); + + return !__is_extent_same(&prev, &et->largest); +} + +unsigned int f2fs_shrink_extent_tree(struct f2fs_sb_info *sbi, int nr_shrink) +{ + struct extent_tree *treevec[EXT_TREE_VEC_SIZE]; + struct extent_node *en, *tmp; + unsigned long ino = F2FS_ROOT_INO(sbi); + struct radix_tree_root *root = &sbi->extent_tree_root; + unsigned int found; + unsigned int node_cnt = 0, tree_cnt = 0; + int remained; + + if (!test_opt(sbi, EXTENT_CACHE)) + return 0; + + if (!down_write_trylock(&sbi->extent_tree_lock)) + goto out; + + /* 1. remove unreferenced extent tree */ + while ((found = radix_tree_gang_lookup(root, + (void **)treevec, ino, EXT_TREE_VEC_SIZE))) { + unsigned i; + + ino = treevec[found - 1]->ino + 1; + for (i = 0; i < found; i++) { + struct extent_tree *et = treevec[i]; + + if (!atomic_read(&et->refcount)) { + write_lock(&et->lock); + node_cnt += __free_extent_tree(sbi, et, true); + write_unlock(&et->lock); + + radix_tree_delete(root, et->ino); + kmem_cache_free(extent_tree_slab, et); + sbi->total_ext_tree--; + tree_cnt++; + + if (node_cnt + tree_cnt >= nr_shrink) + goto unlock_out; + } + } + } + up_write(&sbi->extent_tree_lock); + + /* 2. remove LRU extent entries */ + if (!down_write_trylock(&sbi->extent_tree_lock)) + goto out; + + remained = nr_shrink - (node_cnt + tree_cnt); + + spin_lock(&sbi->extent_lock); + list_for_each_entry_safe(en, tmp, &sbi->extent_list, list) { + if (!remained--) + break; + list_del_init(&en->list); + } + spin_unlock(&sbi->extent_lock); + + while ((found = radix_tree_gang_lookup(root, + (void **)treevec, ino, EXT_TREE_VEC_SIZE))) { + unsigned i; + + ino = treevec[found - 1]->ino + 1; + for (i = 0; i < found; i++) { + struct extent_tree *et = treevec[i]; + + write_lock(&et->lock); + node_cnt += __free_extent_tree(sbi, et, false); + write_unlock(&et->lock); + + if (node_cnt + tree_cnt >= nr_shrink) + break; + } + } +unlock_out: + up_write(&sbi->extent_tree_lock); +out: + trace_f2fs_shrink_extent_tree(sbi, node_cnt, tree_cnt); + + return node_cnt + tree_cnt; +} + +unsigned int f2fs_destroy_extent_node(struct inode *inode) +{ + struct f2fs_sb_info *sbi = F2FS_I_SB(inode); + struct extent_tree *et = F2FS_I(inode)->extent_tree; + unsigned int node_cnt = 0; + + if (!et) + return 0; + + write_lock(&et->lock); + node_cnt = __free_extent_tree(sbi, et, true); + write_unlock(&et->lock); + + return node_cnt; +} + +void f2fs_destroy_extent_tree(struct inode *inode) +{ + struct f2fs_sb_info *sbi = F2FS_I_SB(inode); + struct extent_tree *et = F2FS_I(inode)->extent_tree; + unsigned int node_cnt = 0; + + if (!et) + return; + + if (inode->i_nlink && !is_bad_inode(inode) && et->count) { + atomic_dec(&et->refcount); + return; + } + + /* free all extent info belong to this extent tree */ + node_cnt = f2fs_destroy_extent_node(inode); + + /* delete extent tree entry in radix tree */ + down_write(&sbi->extent_tree_lock); + atomic_dec(&et->refcount); + f2fs_bug_on(sbi, atomic_read(&et->refcount) || et->count); + radix_tree_delete(&sbi->extent_tree_root, inode->i_ino); + kmem_cache_free(extent_tree_slab, et); + sbi->total_ext_tree--; + up_write(&sbi->extent_tree_lock); + + F2FS_I(inode)->extent_tree = NULL; + + trace_f2fs_destroy_extent_tree(inode, node_cnt); +} + +bool f2fs_lookup_extent_cache(struct inode *inode, pgoff_t pgofs, + struct extent_info *ei) +{ + if (!f2fs_may_extent_tree(inode)) + return false; + + return f2fs_lookup_extent_tree(inode, pgofs, ei); +} + +void f2fs_update_extent_cache(struct dnode_of_data *dn) +{ + struct f2fs_inode_info *fi = F2FS_I(dn->inode); + pgoff_t fofs; + + if (!f2fs_may_extent_tree(dn->inode)) + return; + + f2fs_bug_on(F2FS_I_SB(dn->inode), dn->data_blkaddr == NEW_ADDR); + + + fofs = start_bidx_of_node(ofs_of_node(dn->node_page), fi) + + dn->ofs_in_node; + + if (f2fs_update_extent_tree_range(dn->inode, fofs, dn->data_blkaddr, 1)) + sync_inode_page(dn); +} + +void f2fs_update_extent_cache_range(struct dnode_of_data *dn, + pgoff_t fofs, block_t blkaddr, unsigned int len) + +{ + if (!f2fs_may_extent_tree(dn->inode)) + return; + + if (f2fs_update_extent_tree_range(dn->inode, fofs, blkaddr, len)) + sync_inode_page(dn); +} + +void init_extent_cache_info(struct f2fs_sb_info *sbi) +{ + INIT_RADIX_TREE(&sbi->extent_tree_root, GFP_NOIO); + init_rwsem(&sbi->extent_tree_lock); + INIT_LIST_HEAD(&sbi->extent_list); + spin_lock_init(&sbi->extent_lock); + sbi->total_ext_tree = 0; + atomic_set(&sbi->total_ext_node, 0); +} + +int __init create_extent_cache(void) +{ + extent_tree_slab = f2fs_kmem_cache_create("f2fs_extent_tree", + sizeof(struct extent_tree)); + if (!extent_tree_slab) + return -ENOMEM; + extent_node_slab = f2fs_kmem_cache_create("f2fs_extent_node", + sizeof(struct extent_node)); + if (!extent_node_slab) { + kmem_cache_destroy(extent_tree_slab); + return -ENOMEM; + } + return 0; +} + +void destroy_extent_cache(void) +{ + kmem_cache_destroy(extent_node_slab); + kmem_cache_destroy(extent_tree_slab); +} |