From 94ebf71bddbcd4ab1ce43ae32c6cb66396d2d51a Mon Sep 17 00:00:00 2001 From: Baokun Li <libaokun1@huawei.com> 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 <jack@suse.cz> Fixes: 6bd97bf273bd ("ext4: remove redundant mb_regenerate_buddy()") Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20240104142040.2835097-4-libaokun1@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Baokun Li <libaokun1@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> --- fs/ext4/mballoc.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 46da6845c3072..d66ba6f6a8115 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -823,6 +823,24 @@ void ext4_mb_generate_buddy(struct super_block *sb, atomic64_add(period, &sbi->s_mb_generation_time); } +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 @@ -1505,6 +1523,8 @@ 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; } -- GitLab