From: Jan Kara jack@suse.cz
[ Upstream commit 173b6e383d2a204c9921ffc1eca3b87aa2106c33 ]
A user reported FITRIM ioctl failing for him on ext4 on some devices without apparent reason. After some debugging we've found out that these devices (being LVM volumes) report rather large discard granularity of 42MB and the filesystem had 1k blocksize and thus group size of 8MB. Because ext4 FITRIM implementation puts discard granularity into minlen, ext4_trim_fs() declared the trim request as invalid. However just silently doing nothing seems to be a more appropriate reaction to such combination of parameters since user did not specify anything wrong.
CC: Lukas Czerner lczerner@redhat.com Fixes: 5c2ed62fd447 ("ext4: Adjust minlen with discard_granularity in the FITRIM ioctl") Signed-off-by: Jan Kara jack@suse.cz Link: https://lore.kernel.org/r/20211112152202.26614-1-jack@suse.cz Signed-off-by: Theodore Ts'o tytso@mit.edu Signed-off-by: Sasha Levin sashal@kernel.org --- fs/ext4/ioctl.c | 2 -- fs/ext4/mballoc.c | 8 ++++++++ 2 files changed, 8 insertions(+), 2 deletions(-)
diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c index cb54ea6461fd8..413bf3d2f7844 100644 --- a/fs/ext4/ioctl.c +++ b/fs/ext4/ioctl.c @@ -1123,8 +1123,6 @@ resizefs_out: sizeof(range))) return -EFAULT;
- range.minlen = max((unsigned int)range.minlen, - q->limits.discard_granularity); ret = ext4_trim_fs(sb, &range); if (ret < 0) return ret; diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index d7cb7d719ee58..60aef7fdd61d0 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -5815,6 +5815,7 @@ out: */ int ext4_trim_fs(struct super_block *sb, struct fstrim_range *range) { + struct request_queue *q = bdev_get_queue(sb->s_bdev); struct ext4_group_info *grp; ext4_group_t group, first_group, last_group; ext4_grpblk_t cnt = 0, first_cluster, last_cluster; @@ -5833,6 +5834,13 @@ int ext4_trim_fs(struct super_block *sb, struct fstrim_range *range) start >= max_blks || range->len < sb->s_blocksize) return -EINVAL; + /* No point to try to trim less than discard granularity */ + if (range->minlen < q->limits.discard_granularity) { + minlen = EXT4_NUM_B2C(EXT4_SB(sb), + q->limits.discard_granularity >> sb->s_blocksize_bits); + if (minlen > EXT4_CLUSTERS_PER_GROUP(sb)) + goto out; + } if (end >= max_blks) end = max_blks - 1; if (end <= first_data_blk)