f2fs: sync to upstream
https://git.kernel.org/cgit/linux/kernel/git/jaegeuk/f2fs.git/commit/?h=linux-3.4&id=994642cfdbc08f1eda7ff48504f779cbcc9e3067
Change-Id: I5beb230d4a5dc3ef3913f5bfc4c28b39bcb755b1
diff --git a/fs/f2fs/extent_cache.c b/fs/f2fs/extent_cache.c
new file mode 100644
index 0000000..a38ee9b
--- /dev/null
+++ b/fs/f2fs/extent_cache.c
@@ -0,0 +1,748 @@
+/*
+ * 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, unsigned int len)
+{
+ struct extent_info *largest = &F2FS_I(inode)->extent_tree->largest;
+
+ if (fofs < largest->fofs + largest->len && fofs + len > largest->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, 1);
+}
+
+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) {
+ __try_update_largest_extent(et, en);
+ 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;
+
+ __try_update_largest_extent(et, en);
+ et->cached_en = en;
+ return en;
+}
+
+static 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;
+ 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;
+
+ trace_f2fs_update_extent_tree_range(inode, fofs, blkaddr, len);
+
+ 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;
+
+ /*
+ * drop largest extent before lookup, in case it's already
+ * been shrunk from extent tree
+ */
+ __drop_largest_extent(inode, fofs, len);
+
+ /* 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)
+ en = next_en;
+
+ /* 2. invlidate all extent nodes in range [fofs, fofs + len - 1] */
+ while (en && en->ei.fofs < end) {
+ unsigned int org_end;
+ int parts = 0; /* # of parts current extent split into */
+
+ next_en = en1 = NULL;
+
+ dei = en->ei;
+ org_end = dei.fofs + dei.len;
+ f2fs_bug_on(sbi, pos >= org_end);
+
+ if (pos > dei.fofs && pos - dei.fofs >= F2FS_MIN_EXTENT_LEN) {
+ en->ei.len = pos - en->ei.fofs;
+ prev_en = en;
+ parts = 1;
+ }
+
+ if (end < org_end && org_end - end >= F2FS_MIN_EXTENT_LEN) {
+ if (parts) {
+ set_extent_info(&ei, end,
+ end - dei.fofs + dei.blk,
+ org_end - end);
+ en1 = __insert_extent_tree(sbi, et, &ei,
+ NULL, NULL);
+ next_en = en1;
+ } else {
+ en->ei.fofs = end;
+ en->ei.blk += end - dei.fofs;
+ en->ei.len -= end - dei.fofs;
+ next_en = en;
+ }
+ parts++;
+ }
+
+ if (!next_en) {
+ struct rb_node *node = rb_next(&en->rb_node);
+
+ next_en = node ?
+ rb_entry(node, struct extent_node, rb_node)
+ : NULL;
+ }
+
+ if (parts)
+ __try_update_largest_extent(et, en);
+ else
+ __detach_extent_node(sbi, et, en);
+
+ /*
+ * if original extent is split into zero or two parts, extent
+ * tree has been altered by deletion or insertion, therefore
+ * invalidate pointers regard to tree.
+ */
+ if (parts != 1) {
+ insert_p = NULL;
+ insert_parent = NULL;
+ }
+
+ /* update in global extent list */
+ spin_lock(&sbi->extent_lock);
+ if (!parts && !list_empty(&en->list))
+ list_del(&en->list);
+ if (en1)
+ list_add_tail(&en1->list, &sbi->extent_list);
+ spin_unlock(&sbi->extent_lock);
+
+ /* release extent node */
+ if (!parts)
+ kmem_cache_free(extent_node_slab, en);
+
+ en = next_en;
+ }
+
+ /* 3. update extent in extent cache */
+ if (blkaddr) {
+ struct extent_node *den = NULL;
+
+ set_extent_info(&ei, fofs, blkaddr, len);
+ en1 = __try_merge_extent_node(sbi, et, &ei, &den,
+ prev_en, next_en);
+ if (!en1)
+ en1 = __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 (en1) {
+ if (list_empty(&en1->list))
+ list_add_tail(&en1->list, &sbi->extent_list);
+ else
+ list_move_tail(&en1->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);
+
+ /*
+ * reset ino for searching victims from beginning of global extent tree.
+ */
+ ino = F2FS_ROOT_INO(sbi);
+
+ 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);
+}