From c1317822e2de80e78f137d3a2d99febab1b80326 Mon Sep 17 00:00:00 2001 From: Baokun Li Date: Thu, 4 Jan 2024 22:20:35 +0800 Subject: [PATCH] ext4: regenerate buddy after block freeing failed if under fc replay commit c9b528c35795b711331ed36dc3dbee90d5812d4e upstream. This mostly reverts commit 6bd97bf273bd ("ext4: remove redundant mb_regenerate_buddy()") and reintroduces mb_regenerate_buddy(). Based on code in mb_free_blocks(), fast commit replay can end up marking as free blocks that are already marked as such. This causes corruption of the buddy bitmap so we need to regenerate it in that case. Reported-by: Jan Kara Fixes: 6bd97bf273bd ("ext4: remove redundant mb_regenerate_buddy()") Signed-off-by: Baokun Li Reviewed-by: Jan Kara Link: https://lore.kernel.org/r/20240104142040.2835097-4-libaokun1@huawei.com Signed-off-by: Theodore Ts'o Signed-off-by: Baokun Li Signed-off-by: Greg Kroah-Hartman --- fs/ext4/mballoc.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 622f60d9e1c68..6bf98e61ed46d 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -1168,6 +1168,24 @@ void ext4_mb_generate_buddy(struct super_block *sb, mb_update_avg_fragment_size(sb, grp); } +static void mb_regenerate_buddy(struct ext4_buddy *e4b) +{ + int count; + int order = 1; + void *buddy; + + while ((buddy = mb_find_buddy(e4b, order++, &count))) + ext4_set_bits(buddy, 0, count); + + e4b->bd_info->bb_fragments = 0; + memset(e4b->bd_info->bb_counters, 0, + sizeof(*e4b->bd_info->bb_counters) * + (e4b->bd_sb->s_blocksize_bits + 2)); + + ext4_mb_generate_buddy(e4b->bd_sb, e4b->bd_buddy, + e4b->bd_bitmap, e4b->bd_group, e4b->bd_info); +} + /* The buddy information is attached the buddy cache inode * for convenience. The information regarding each group * is loaded via ext4_mb_load_buddy. The information involve @@ -1846,6 +1864,8 @@ static void mb_free_blocks(struct inode *inode, struct ext4_buddy *e4b, ext4_mark_group_bitmap_corrupted( sb, e4b->bd_group, EXT4_GROUP_INFO_BBITMAP_CORRUPT); + } else { + mb_regenerate_buddy(e4b); } goto done; }