Re: [PATCH 4/6 v9] fs: New helper legitimize_mntget() for getting a legitimize mnt

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Wed, Aug 19, 2015 at 02:56:50PM +1000, NeilBrown wrote:
> If not, we need to clean up and try again.
> To do this we need to check MNT_SYNC_UMOUNT.
> If that is clear it is safe and best to call mntput() on the mnt.
> If it is set, then we just do the mnt_add_count(mnt, -1) and give up
> completely.

It's more subtle, actually.  See my reply upthread for details, but
basically we rely on rcu_read_lock() held since before that MNT_SYNC_UMOUNT
had been set, making synchronize_rcu() in namespace_unlock() a guaranteed
delay of the final mntput until after we have returned.
--
To unsubscribe from this list: send the line "unsubscribe linux-nfs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html



[Index of Archives]     [Linux Filesystem Development]     [Linux USB Development]     [Linux Media Development]     [Video for Linux]     [Linux NILFS]     [Linux Audio Users]     [Yosemite Info]     [Linux SCSI]

  Powered by Linux