xfs_quota: bug: traverses bind mountpoints

[Paul Nienaber]

So, much like coreutils' du (which also shouldn't), xfs_quota traverses 
bind mountpoints both when doing 'project -s' and 'project -C', and 
probably also 'project -c' although I haven't tested it.  Testcase and 
output follows.

cheers
~Paul

# dd if=/dev/zero of=./xfstestfs bs=1M count=512
512+0 records in
512+0 records out
536870912 bytes (537 MB) copied, 0.402579 s, 1.3 GB/s
# mkfs.xfs xfstestfs
meta-data=xfstestfs              isize=256    agcount=4, agsize=32768 blks
          =                       sectsz=512   attr=2, projid32bit=0
data     =                       bsize=4096   blocks=131072, imaxpct=25
          =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0
log      =internal log           bsize=4096   blocks=1200, version=2
          =                       sectsz=512   sunit=0 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0
# mkdir /mnt/xfstestfs
# mount -t xfs -o loop,prjquota xfstestfs /mnt/xfstestfs/
# mkdir -p /mnt/xfstestfs/projects/foo/chroot/xfstestfs
# mkdir -p /mnt/xfstestfs/projects/bar
****This is here so we get spew about where it's traversing later on:
# ln -s /mnt/xfstestfs/projects/foo /mnt/xfstestfs/projects/bar/
# echo 12345:/mnt/xfstestfs/projects/foo >> /etc/projects
# echo foo:12345 >> /etc/projid
# mount -t none -o bind /mnt/xfstestfs 
/mnt/xfstestfs/projects/foo/chroot/xfstestfs
# dd if=/dev/zero of=/mnt/xfstestfs/projects/foo/100M bs=1M count=100
100+0 records in
100+0 records out
104857600 bytes (105 MB) copied, 0.0815913 s, 1.3 GB/s
# dd if=/dev/zero of=/mnt/xfstestfs/projects/bar/100M bs=1M count=100
100+0 records in
100+0 records out
104857600 bytes (105 MB) copied, 0.0806148 s, 1.3 GB/s
# xfs_quota -x -c 'project -s foo' /mnt/xfstestfs
Setting up project foo (path /mnt/xfstestfs/projects/foo)...
****Oops, why are we here:
xfs_quota: skipping special file 
/mnt/xfstestfs/projects/foo/chroot/xfstestfs/projects/bar/foo
Processed 1 (/etc/projects and cmdline) paths for project foo with 
recursion depth infinite (-1).
# xfs_quota -x -c 'report -p -h' /mnt/xfstestfs
Project quota on /mnt/xfstestfs (/dev/loop0)
                         Blocks
Project ID   Used   Soft   Hard Warn/Grace
---------- ---------------------------------
foo          200M      0      0  00 [------]