[XFS] Flush and invalidate dirty pages at the start of a direct read also,

else we can hit a delalloc-extents-via-direct-io BUG.

SGI-PV: 949916
SGI-Modid: xfs-linux-melb:xfs-kern:25483a

Signed-off-by: Nathan Scott <nathans@sgi.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/fs/xfs/linux-2.6/xfs_lrw.c b/fs/xfs/linux-2.6/xfs_lrw.c
index ba07b83f988d..2a936bd38ce7 100644
--- a/fs/xfs/linux-2.6/xfs_lrw.c
+++ b/fs/xfs/linux-2.6/xfs_lrw.c
@@ -270,6 +270,10 @@ xfs_read(
                 }
         }
 
+        if (unlikely((ioflags & IO_ISDIRECT) && VN_CACHED(vp)))
+                VOP_FLUSHINVAL_PAGES(vp, ctooff(offtoct(*offset)),
+                                                -1, FI_REMAPF_LOCKED);
+
         xfs_rw_enter_trace(XFS_READ_ENTER, &ip->i_iocore,
                                 (void *)iovp, segs, *offset, ioflags);
         ret = __generic_file_aio_read(iocb, iovp, segs, offset);