[PATCH v2 23/35] ubifs: set/clear MS_RDONLY properly in ubifs_remount

[Dongsheng Yang]

On 08/09/2015 05:17 AM, Richard Weinberger wrote:
> Am 30.07.2015 um 07:48 schrieb Dongsheng Yang:
>> We need to set or clear MS_RDONLY in remounting.
>
> Care to explain why?
> Does the quota subsystem need that information?
> If so, where?

Ha, yes, you are right.

When we remount to rw from ro, we need to call dquot_resume.
And dquot_resume will call vfs_load_quota_inode() which
will check the MS_RDONLY. If it's ro mode, will return
an -EROFS.

And I know that we are using ->ro_mount in ubifs
to store the mounted mode. So we don't care about
the MS_RDONLY in ubifs. But why not to tell vfs we are in
ro or rw? Does it cause any problem?

Thanx
YAng

> Thanks,
> //richard
> .
>