On Wed, Aug 31, 2011 at 06:12:04PM -0700, Allison Henderson wrote: > Oh, I meant for this to go to linux-fsdevel instead of linux-kernel, but > all feedback is welcome! :) > > On 08/31/2011 05:33 PM, Allison Henderson wrote: >> Hi All, >> >> In ext4 punch hole, we realized that the punch hole operation needs to >> be done under i_mutex just like truncate. i_mutex for truncate is held >> in the vfs layer, so we dont need to lock it at the file system layer, >> but vfs does not lock i_mutex for fallocate. We can lock i_mutex for >> fallocate at the fs layer, but question was raised then: should i_mutex >> for fallocate be held in the vfs layer instead? I do not know if other >> file systems need i_mutex to be locked for fallocate, or if they might >> be locking it already, so I am doing some investigating on this idea, >> and also the appropriate use of i_mutex in general. Can someone provide >> some insight this topic? Thx! >> Btrfs has range locking for our extents, so we don't really need to be holding the i_mutex, even tho it appears we do it anyway. So I'd rather this not be moved to VFS for us who can do more fine grained locking. Thanks, Josef -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
