On Wed 14-10-15 09:31:38, Ross Zwisler wrote: > On Wed, Oct 14, 2015 at 10:51:19AM +0200, Jan Kara wrote: > > On Tue 13-10-15 16:25:37, Ross Zwisler wrote: > > > Add locking to ensure that DAX faults are isolated from ext2 operations > > > that modify the data blocks allocation for an inode. This is intended to > > > be analogous to the work being done in XFS by Dave Chinner: > > > > > > http://www.spinics.net/lists/linux-fsdevel/msg90260.html > > > > > > Compared with XFS the ext2 case is greatly simplified by the fact that ext2 > > > already allocates and zeros new blocks before they are returned as part of > > > ext2_get_block(), so DAX doesn't need to worry about getting unmapped or > > > unwritten buffer heads. > > > > > > This means that the only work we need to do in ext2 is to isolate the DAX > > > faults from inode block allocation changes. I believe this just means that > > > we need to isolate the DAX faults from truncate operations. > > > > > > The newly introduced dax_sem is intended to replicate the protection > > > offered by i_mmaplock in XFS. In addition to truncate the i_mmaplock also > > > protects XFS operations like hole punching, fallocate down, extent > > > manipulation IOCTLS like xfs_ioc_space() and extent swapping. Truncate is > > > the only one of these operations supported by ext2. > > > > > > Signed-off-by: Ross Zwisler <ross.zwisler@xxxxxxxxxxxxxxx> > > > > The patch looks good to me. Feel free to add: > > > > Reviewed-by: Jan Kara <jack@xxxxxxxx> > > > > Or I can push the patch through my tree as it seems to be independent of > > any other changes, am I right? > > > > Honza > > Yep, it is independent of other patches. It'd be great if you pushed it up > through your tree, thanks! I've pulled the patch into my tree and will push it to Linus in the next merge window. Honza -- Jan Kara <jack@xxxxxxxx> SUSE Labs, CR -- 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
