Re: Setting project quotas on special files

[Jeff Liu <jeff.liu@oracle.com>]

On 11/10 2013 15:39 PM, Tiziano Müller wrote:
> Hi everyone
>
> It started with the following error:
>
>    dev # cp -al dvd dvd2
>    cp: cannot create hard link ‘dvd2’ to ‘dvd’: Invalid cross-device link
>
> "dvd" is in this case a symlink (but I also did the test with special
> devices).
This definitely would fail if you trying to create hard links across
volumes.
>
> What I did was: copy that symlink from somewhere else, trying to turn on
> project quotas on a parent directoy of that "dev" directory which gives
> me:
>
>   xfs_quota: skipping special file /var/foo/dev/dvd
symlink files will be skipped and xfs_quota consider it as special file
just like fifo, sock, etc...

If xfs_quota do check with follow symlinks, then the project id is potentially
applied to files on another filesystem. 

>
> When I examine the inode using xfs_db I get for my "dvd" symlink:
>
>   core.projid_lo = 0
>   core.projid_hi = 0
>
> When I create a new symlink "foo" (with the same uid+gid as "dvd") and
> examine it's inode using xfs_db:
>
>   core.projid_lo = 2398
>   core.projid_hi = 61
>
> What I therefore seem to encounter is the problem mentioned in xfs_quota
> for the project subcommand:
>
>   An attempt to create a hard link to a file in the tree will only succeed if the project identi‐
>        fier matches the project identifier for the tree.
>
> I could now use xfs_io to fix all special files once (since newly
> created ones will carry the project id directly), but why does
> "xfs_quota -x -c 'project -s test1' /var" skip special files if it is
> clearly possible and required to set the project id on them to have
> hardlinks working again within the project dir?
Sorry if I misunderstood your question, but the existing hard link files
would
notbe skipped IMO.  For the project subcommand, it means we could not create
hardlinks cross different project trees.

Thanks,
-Jeff

_______________________________________________
xfs mailing list
xfs@oss.sgi.com
http://oss.sgi.com/mailman/listinfo/xfs