Re: [PATCH] UBIFS: Add freeze support in ubifs

[Dongsheng Yang <yangds.fnst@cn.fujitsu.com>]

On 09/27/2015 04:06 PM, Richard Weinberger wrote:
> Yang,
>
> Am 27.09.2015 um 04:39 schrieb Dongsheng Yang:
>> We need to do nothing in ubifs, as all is already done in vfs.
>
> Please more details. :-)

Oh, this patch is really an incorrect one. At least I have to add
sb_start/end_intwrite and sb_start/end_pagefault in ubifs at
first. And I have to add more details about what I am doing and
why. Will send v2 later.

I think I was out of my mind yesterday, this patch is really not ready
to go in my local box. :(

Sorry for the noisy.

Yang
> The current changelog reads like every filesystem should implement
> it as nop. Which is obviously not the case.
>
> fs/super.c checks whether ->freeze_fs() is implemented, so
> a nop-implementation does not make sense here.
>
> I bet you hit this in fs/ioctl.c:
>          /* If filesystem doesn't support freeze feature, return. */
>          if (sb->s_op->freeze_fs == NULL && sb->s_op->freeze_super == NULL)
>                  return -EOPNOTSUPP;
>
> Correct?
>
> And the most important detail is missing, why is UBIFS allowed
> to have a nop-implementation?
>
> Thanks,
> //richard
> .
>