diff options
author | Filipe Manana <fdmanana@suse.com> | 2022-11-02 12:46:35 +0000 |
---|---|---|
committer | David Sterba <dsterba@suse.com> | 2022-11-02 17:44:42 +0100 |
commit | a348c8d4f6cf23ef04b0edaccdfe9d94c2d335db (patch) | |
tree | 956efbb80f9364e32a889315c55fa2dd6e77bf95 /fs | |
parent | d0ea17aec12ea0f7b9d2ed727d8ef8169d1e7699 (diff) |
btrfs: fix nowait buffered write returning -ENOSPC
If we are doing a buffered write in NOWAIT context and we can't reserve
metadata space due to -ENOSPC, then we should return -EAGAIN so that we
retry the write in a context allowed to block and do metadata reservation
with flushing, which might succeed this time due to the allowed flushing.
Returning -ENOSPC while in NOWAIT context simply makes some writes fail
with -ENOSPC when they would likely succeed after switching from NOWAIT
context to blocking context. That is unexpected behaviour and even fio
complains about it with a warning like this:
fio: io_u error on file /mnt/sdi/task_0.0.0: No space left on device: write offset=1535705088, buflen=65536
fio: pid=592630, err=28/file:io_u.c:1846, func=io_u error, error=No space left on device
The fio's job config is this:
[global]
bs=64K
ioengine=io_uring
iodepth=1
size=2236962133
nr_files=1
filesize=2236962133
direct=0
runtime=10
fallocate=posix
io_size=2236962133
group_reporting
time_based
[task_0]
rw=randwrite
directory=/mnt/sdi
numjobs=4
So fix this by returning -EAGAIN if we are in NOWAIT context and the
metadata reservation failed with -ENOSPC.
Fixes: 304e45acdb8f ("btrfs: plumb NOWAIT through the write path")
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Diffstat (limited to 'fs')
-rw-r--r-- | fs/btrfs/file.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c index d55ad46384d1..5ce2ae9d4f72 100644 --- a/fs/btrfs/file.c +++ b/fs/btrfs/file.c @@ -1598,6 +1598,9 @@ static noinline ssize_t btrfs_buffered_write(struct kiocb *iocb, write_bytes); else btrfs_check_nocow_unlock(BTRFS_I(inode)); + + if (nowait && ret == -ENOSPC) + ret = -EAGAIN; break; } |