Re: Re: [PATCH 2/2] ceph: Add pg_name filed in struct ceph_ioctl_dataloc.

[majianpeng <majianpeng@gmail.com>]

>On Mon, 5 Aug 2013, majianpeng wrote:
>> As the 'ceph help' print, it will print pgs.But now it can't.
>> So we add this.There are two type name of pg, temp and stable.
>> Because the command 'ceph pg dump' print temp name,so we also print the
>> temp name of pg.
>
>Unfortunately we can't modify the ioctl structure like this without 
>breaking the kernel/userspace ABI (a big no-no).  The usual way around 
>that is to make a new ioctl (like CEPH_IOC_GET_DATALOC2) and a new 
>structure (struct ceph_ioctl_dataloc2) with the additional fields.
>
>What is this going to be used for?  You can get the full info from the 
>montior with the 'ceph osd map <pool name> <object name> --format=json'.  
>Does it need to come from the kernel this way?
>
I only want to print the pgid when print other infos using cephfs map or sho_location.
I'll dig into the implementation of 'ceph osd map <pool name> <object name> --format=json'.

Thanks!
Jianpeng Ma