[PATCH 6/6] ioctl eofblocks: require non-privileged users to specify uid/gid match

[Brian Foster]

On 06/28/2013 07:22 PM, Dwight Engen wrote:
> On Fri, 28 Jun 2013 17:39:13 -0400
> Brian Foster <bfoster at redhat.com> wrote:
> 
>> On 06/28/2013 04:28 PM, Dwight Engen wrote:
>>> On Fri, 28 Jun 2013 14:50:24 -0400
>>> Brian Foster <bfoster at redhat.com> wrote:
>>>
>>>> On 06/28/2013 11:11 AM, Dwight Engen wrote:
...
>>
>> To be honest, there aren't any real users of the eofblocks command
>> from userspace that I'm aware of at the moment. I added it originally
>> for a poc quota implementation I was working on for gluster, but the
>> primary use case for the scanning mechanism is to allow background
>> clean up of files such that post-eof speculative preallocation
>> doesn't hang around for too long.
> 
> ... and there are likely to be scenarios where waiting for the timer
> would be too long?
>  

Well one can adjust the timer via the /proc file if necessary. Our use
case was along the lines of ensuring prealloc was cleared up at certain
points where we wanted to track space usage (using a cluster of XFS
project quotas to represent a higher level quota), iirc. It's been a
while since I've looked at that code... ;)

>>> Maybe this permission stuff should be a separate change since it
>>> isn't really related to user namespace stuff? I just happened to be
>>> in the vicinity and am happy to help :)
>>>
>>
>> Sounds reasonable to me. :)
> 
> If you want me to code up either option, let me know.
>  

Feel free to. :) I agree that it's separate from the userns work.
I'll put it on my todo list if you don't get around to it.

Brian

>> Brian