[XFS] Disable the combination of XFS direct IO and AIO until the IO completion
handling for unwritten extents can be moved out of interrupt context.

SGI Modid: xfs-linux:xfs-kern:22343a

Signed-off-by: Nathan Scott <nathans@sgi.com>
Signed-off-by: Christoph Hellwig <hch@sgi.com>
diff --git a/fs/xfs/linux-2.6/xfs_lrw.c b/fs/xfs/linux-2.6/xfs_lrw.c
index ff145fd..aa9daae 100644
--- a/fs/xfs/linux-2.6/xfs_lrw.c
+++ b/fs/xfs/linux-2.6/xfs_lrw.c
@@ -683,6 +683,9 @@
 			(xip->i_d.di_flags & XFS_DIFLAG_REALTIME) ?
 				mp->m_rtdev_targp : mp->m_ddev_targp;
 
+		if (ioflags & IO_ISAIO)
+			return XFS_ERROR(-ENOSYS);
+
 		if ((pos & target->pbr_smask) || (count & target->pbr_smask))
 			return XFS_ERROR(-EINVAL);