On Wed, May 06, 2009 at 02:26:30AM -0400, Christoph Hellwig wrote: > On Wed, May 06, 2009 at 04:51:38AM +0100, Al Viro wrote: > > Actually, I'm not sure that you are right. Especially if we go for your > > "always hold s_umount for sync_filesystem()"; in that case we are guaranteed > > that we'll have an exclusion between ->write_super() and that sucker, so > > there's no reason to push it down into filesystems that do not use lock_super() > > The interesting cases are locking against internal s_lock which at least > extN needs or ->write_super. And I'd really be rather safe than sorry > and audit individual filesystems than introducing bug in an obscure one. write_super() can *not* get contention against remount. That's the point. And other that write_super, we have very few filesystems that even mention lock_super() anywhere. Yes, ext3 and ext4. Also fat, sysv, ufs and hpfs. That's it. Compare with the number of suckers that have write_super() and especially remount_fs()... -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
