On Fri, Jan 09, 2015 at 09:04:12AM +1100, Dave Chinner wrote: > On Thu, Jan 08, 2015 at 01:21:29PM -0800, Jaegeuk Kim wrote: > > On Fri, Jan 09, 2015 at 07:54:16AM +1100, Dave Chinner wrote: > > > On Thu, Jan 08, 2015 at 02:33:17PM -0600, Eric Sandeen wrote: > > > > On 1/8/15 2:18 PM, Jaegeuk Kim wrote: > > > > > On Thu, Jan 08, 2015 at 01:54:20PM -0600, Eric Sandeen wrote: > > > > >> On 1/8/15 12:10 PM, Jaegeuk Kim wrote: > > > > >>> This patch add an ioctl to shutdown f2fs, which stops all the further block > > > > >>> writes after this point. > > > > >> > > > > >> would it make sense to just re-use the xfs ioctl nr, if the semantics are > > > > >> the same? > > > > > > > > > > The semantics are not same for now. > > > > > In order to reuse xfs ioctl, it needs to support options for flushing logs. > > > > > > > > the xfs iotl has 3 behaviors optional: > > > > > > > > #define XFS_FSOP_GOING_FLAGS_DEFAULT 0x0 /* going down */ > > > > #define XFS_FSOP_GOING_FLAGS_LOGFLUSH 0x1 /* flush log but not data */ > > > > #define XFS_FSOP_GOING_FLAGS_NOLOGFLUSH 0x2 /* don't flush log nor data */ > > > > > > > > if f2fs currently supports a subset, you could just -EOPNOTSUPP on the others. > > > > > > No, just do a default shutdown operation if the semantics cannot be > > > supported. > > > > > > - XFS_FSOP_GOING_FLAGS_DEFAULT == > > > consistent on disk before shutdown > > > + implemented by freeze/thaw/shutdown sequence > > > - XFS_FSOP_GOING_FLAGS_LOGFLUSH == > > > consistent journal on disk before shutdown > > > + implemented by journal flush/shutdown sequence > > I should point out that this is really "consistent metadata on > disk before shutdown", so it really doesn't matter if your > filesystem has a journal or not, it can still be implemented. Agreed. I just implemented these three options for f2fs. For the f2fs perspective, DEFAULT conducts - flushing all the user and dentry blocks - checkpointing and then shutdowning fs LOGFLUSH conducts - checkpointing and then shutdowning fs NOLOGFLUSH conducts - shutdowning fs > > Perhaps it woul dbe best to rename them for a generic ioctl > to FS_GOING_DOWN_SYNC, FS_GOING_DOWN_METADATA_METASYNC > and FS_GOING_DOWN_NOSYNC... How about FS_GOING_DOWN_FULLSYNC, FS_GOING_DOWN_METASYNC, and FS_GOING_DOWN_NOSYNC? Thanks, > > Cheers, > > Dave. > -- > Dave Chinner > david@xxxxxxxxxxxxx -- 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
