On 1/26/16 11:52 AM, Jan Kara wrote:
> Yeah, so VFS quotas use ESRCH when quota for particular fs is not enabled
> (while ENOENT means device you passed in doesn't exist).
And what does it return for "that ID has no quota?" Anything? Maybe not,
see below?
> So probably a
> solution that keeps XFS and VFS interfaces most selfconsistent is to return
> ENOENT from Q_XGETNEXTQUOTA and ESRCH from Q_GETNEXTQUOTA. I'll update your
> patches in this sense in the comments and changelogs. But XFS patches
> (which I don't carry) need updating the actual code...
Actually, ok, now I'm a little more confused.
Today, Q_XGETQUOTA and Q_GETQUOTA will both return -ENOENT on XFS if a
quota doesn't exist for that ID:
quotactl(Q_GETQUOTA|USRQUOTA, "/dev/sdb2", 123456789, 0x7ffdf2edbc80) = -1
ENOENT (No such file or directory)
quotactl(Q_XGETQUOTA|USRQUOTA, "/dev/sdb2", 123456789, 0x7ffdf2edbc10) = -1
ENOENT (No such file or directory)
It seems like the *NEXT* variants (on xfs at least?) may as well continue to do
the same...
But on ext4, I see 0 returned for a nonexistent quota:
quotactl(Q_GETQUOTA|USRQUOTA, "/dev/sdb1", 123456789, {bhardlimit=0,
bsoftlimit=0, curspace=0, ihardlimit=0, isoftlimit=0, curinodes=0, ...}) = 0
quotactl(Q_XGETQUOTA|USRQUOTA, "/dev/sdb1", 123456789, {version=1,
flags=XFS_USER_QUOTA, fieldmask=0, id=123456789, blk_hardlimit=0,
blk_softlimit=0, ino_hardlimit=0, ino_softlimit=0, bcount=0, icount=0, ...}) = 0
So the difference doesn't seem to be XGETQUOTA vs GETQUOTA, rather it's the
filesystem handling the call?
Still, we do need a way to pass back "No more quotas to find" from
Q_[X]GETNEXTQUOTA; XFS will do -ENOENT, but if -ENOENT and -ESRCH already have
specific meanings on non-xfs filesystems, I'm not sure where we go from there.
Sorry for my confusion. :(
-Eric
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