6.6-stable review patch. If anyone has any objections, please let me know.
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From: Wang Jianjian wangjianjian0@foxmail.com
commit ebf6cb7c6e1241984f75f29f1bdbfa2fe7168f88 upstream.
Commit 7a2fcbf7f85 ("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.co... Signed-off-by: Theodore Ts'o tytso@mit.edu Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/ext4/mballoc.c | 39 ++++++--------------------------------- 1 file changed, 6 insertions(+), 33 deletions(-)
--- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -417,8 +417,6 @@ static const char * const ext4_groupinfo
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 pag * 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 pag
/* 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 @@ -4959,31 +4957,6 @@ try_group_pa: }
/* - * 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 * Need to be called with ext4 group lock held