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ext4: no need to generate from free list in mballoc

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Commit 7a2fcbf7f8 ("ext4: don't use blocks freed but not yet committed in
buddy cache init") added a code to mark as used blocks in the list of not yet
committed freed blocks during initialization of a buddy page. However
ext4_mb_free_metadata() makes sure buddy page is already loaded and takes a
reference to it so it cannot happen that ext4_mb_init_cache() is called
when efd list is non-empty. Just remove the
ext4_mb_generate_from_freelist() call.

Fixes: 7a2fcbf7f85('ext4: don't use blocks freed but not yet committed in buddy cache init')
Signed-off-by: Wang Jianjian <wangjianjian0@foxmail.com>
Link: https://lore.kernel.org/r/tencent_53CBCB1668358AE862684E453DF37B722008@qq.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
This commit is contained in:
Wang Jianjian 2023-08-24 23:56:31 +08:00 committed by Theodore Ts'o
parent 8fedebb5ea
commit ebf6cb7c6e
1 changed files with 6 additions and 33 deletions
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39
fs/ext4/mballoc.c
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@ -417,8 +417,6 @@ static const char * const ext4_groupinfo_slab_names[NR_GRPINFO_CACHES] = {
static void ext4_mb_generate_from_pa(struct super_block *sb, void *bitmap,
ext4_group_t group);
static void ext4_mb_generate_from_freelist(struct super_block *sb, void *bitmap,
ext4_group_t group);
static void ext4_mb_new_preallocation(struct ext4_allocation_context *ac);
static bool ext4_mb_good_group(struct ext4_allocation_context *ac,
@ -1361,17 +1359,17 @@ static int ext4_mb_init_cache(struct page *page, char *incore, gfp_t gfp)
* We place the buddy block and bitmap block
* close together
*/
grinfo = ext4_get_group_info(sb, group);
if (!grinfo) {
err = -EFSCORRUPTED;
goto out;
}
if ((first_block + i) & 1) {
/* this is block of buddy */
BUG_ON(incore == NULL);
mb_debug(sb, "put buddy for group %u in page %lu/%x\n",
group, page->index, i * blocksize);
trace_ext4_mb_buddy_bitmap_load(sb, group);
grinfo = ext4_get_group_info(sb, group);
if (!grinfo) {
err = -EFSCORRUPTED;
goto out;
}
grinfo->bb_fragments = 0;
memset(grinfo->bb_counters, 0,
sizeof(*grinfo->bb_counters) *
@ -1398,7 +1396,7 @@ static int ext4_mb_init_cache(struct page *page, char *incore, gfp_t gfp)
/* mark all preallocated blks used in in-core bitmap */
ext4_mb_generate_from_pa(sb, data, group);
ext4_mb_generate_from_freelist(sb, data, group);
WARN_ON_ONCE(!RB_EMPTY_ROOT(&grinfo->bb_free_root));
ext4_unlock_group(sb, group);
/* set incore so that the buddy information can be
@ -4950,31 +4948,6 @@ try_group_pa:
return false;
}
/*
* the function goes through all block freed in the group
* but not yet committed and marks them used in in-core bitmap.
* buddy must be generated from this bitmap
* Need to be called with the ext4 group lock held
*/
static void ext4_mb_generate_from_freelist(struct super_block *sb, void *bitmap,
ext4_group_t group)
{
struct rb_node *n;
struct ext4_group_info *grp;
struct ext4_free_data *entry;
grp = ext4_get_group_info(sb, group);
if (!grp)
return;
n = rb_first(&(grp->bb_free_root));
while (n) {
entry = rb_entry(n, struct ext4_free_data, efd_node);
mb_set_bits(bitmap, entry->efd_start_cluster, entry->efd_count);
n = rb_next(n);
}
}
/*
* the function goes through all preallocation in this group and marks them
* used in in-core bitmap. buddy must be generated from this bitmap