[XFS] Start writeout earlier (on last close) in the case where we have a

truncate down followed by delayed allocation (buffered writes) - worst
case scenario for the notorious NULL files problem.  This reduces the
window where we are exposed to that problem significantly.

SGI-PV: 917976
SGI-Modid: xfs-linux-melb:xfs-kern:26100a

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

1 files changed, 9 insertions, 44 deletions

diff --git a/fs/xfs/linux-2.6/xfs_fs_subr.c b/fs/xfs/linux-2.6/xfs_fs_subr.c
index 575f2a790f31..f0c56daf4d6d 100644
--- a/fs/xfs/linux-2.6/xfs_fs_subr.c
+++ b/fs/xfs/linux-2.6/xfs_fs_subr.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2000-2002,2005 Silicon Graphics, Inc.
+ * Copyright (c) 2000-2002,2005-2006 Silicon Graphics, Inc.
  * All Rights Reserved.
  *
  * This program is free software; you can redistribute it and/or
@@ -15,40 +15,12 @@
  * along with this program; if not, write the Free Software Foundation,
  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  */
-
 #include "xfs.h"
 
-/*
- * Stub for no-op vnode operations that return error status.
- */
-int
-fs_noerr(void)
-{
-	return 0;
-}
+int  fs_noerr(void) { return 0; }
+int  fs_nosys(void) { return ENOSYS; }
+void fs_noval(void) { return; }
 
-/*
- * Operation unsupported under this file system.
- */
-int
-fs_nosys(void)
-{
-	return ENOSYS;
-}
-
-/*
- * Stub for inactive, strategy, and read/write lock/unlock.  Does nothing.
- */
-/* ARGSUSED */
-void
-fs_noval(void)
-{
-}
-
-/*
- * vnode pcache layer for vnode_tosspages.
- * 'last' parameter unused but left in for IRIX compatibility
- */
 void
 fs_tosspages(
 	bhv_desc_t	*bdp,
@@ -63,11 +35,6 @@ fs_tosspages(
 		truncate_inode_pages(ip->i_mapping, first);
 }
 
-
-/*
- * vnode pcache layer for vnode_flushinval_pages.
- * 'last' parameter unused but left in for IRIX compatibility
- */
 void
 fs_flushinval_pages(
 	bhv_desc_t	*bdp,
@@ -79,16 +46,13 @@ fs_flushinval_pages(
 	struct inode	*ip = vn_to_inode(vp);
 
 	if (VN_CACHED(vp)) {
+		if (VN_TRUNC(vp))
+			VUNTRUNCATE(vp);
 		filemap_write_and_wait(ip->i_mapping);
-
 		truncate_inode_pages(ip->i_mapping, first);
 	}
 }
 
-/*
- * vnode pcache layer for vnode_flush_pages.
- * 'last' parameter unused but left in for IRIX compatibility
- */
 int
 fs_flush_pages(
 	bhv_desc_t	*bdp,
@@ -100,12 +64,13 @@ fs_flush_pages(
 	vnode_t		*vp = BHV_TO_VNODE(bdp);
 	struct inode	*ip = vn_to_inode(vp);
 
-	if (VN_CACHED(vp)) {
+	if (VN_DIRTY(vp)) {
+		if (VN_TRUNC(vp))
+			VUNTRUNCATE(vp);
 		filemap_fdatawrite(ip->i_mapping);
 		if (flags & XFS_B_ASYNC)
 			return 0;
 		filemap_fdatawait(ip->i_mapping);
 	}
-
 	return 0;
 }