[PATCH 24/30] r/o bind mounts: elevate count for xfs timestamp updates

Dave Hansen
2008-02-15T22:50:25Z

Elevate the write count during the xfs m/ctime updates.

XFS has to do it's own timestamp updates due to an unfortunate VFS
design limitation, so it will have to track writers by itself aswell.

[hch: split out from the touch_atime patch as it's not related to it at all]

Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
---

linux-2.6.git-dave/fs/xfs/linux-2.6/xfs_iops.c | 7 -------
linux-2.6.git-dave/fs/xfs/linux-2.6/xfs_lrw.c | 9 ++++++++-
2 files changed, 8 insertions(+), 8 deletions(-)

diff -puN fs/xfs/linux-2.6/xfs_iops.c~r-o-bind-mounts-elevate-writer-count-for-xfs-timestamp-updates fs/xfs/linux-2.6/xfs_iops.c
--- linux-2.6.git/fs/xfs/linux-2.6/xfs_iops.c~r-o-bind-mounts-elevate-writer-count-for-xfs-timestamp-updates 2008-02-15 13:25:56.000000000 -0800
+++ linux-2.6.git-dave/fs/xfs/linux-2.6/xfs_iops.c 2008-02-15 13:25:56.000000000 -0800
@@ -157,13 +157,6 @@ xfs_ichgtime_fast(
*/
ASSERT((flags & XFS_ICHGTIME_ACC) == 0);

- /*
- * We're not supposed to change timestamps in readonly-mounted
- * filesystems. Throw it away if anyone asks us.
- */
- if (unlikely(IS_RDONLY(inode)))
- return;
-
if (flags & XFS_ICHGTIME_MOD) {
tvp = &inode->i_mtime;
ip->i_d.di_mtime.t_sec = (__int32_t)tvp->tv_sec;
diff -puN fs/xfs/linux-2.6/xfs_lrw.c~r-o-bind-mounts-elevate-writer-count-for-xfs-timestamp-updates fs/xfs/linux-2.6/xfs_lrw.c
--- linux-2.6.git/fs/xfs/linux-2.6/xfs_lrw.c~r-o-bind-mounts-elevate-writer-count-for-xfs-timestamp-updates 2008-02-15 13:25:56.000000000 -0800
+++ linux-2.6.git-dave/fs/xfs/linux-2.6/xfs_lrw.c 2008-02-15 13:25:56.000000000 -0800
@@ -51,6 +51,7 @@
#include "xfs_vnodeops.h"

#include <linux/capability.h>
+#include <linux/mount.h>
#include <linux/writeback.h>

@@ -679,10 +680,16 @@ start:
if (new_size > xip->i_size)
xip->i_new_size = new_size;

- if (likely(!(ioflags & IO_INVIS))) {
+ /*
+ * We're not supposed to change timestamps in readonly-mounted
+ * filesystems. Throw it away if anyone asks us.
+ */
+ if (likely(!(ioflags & IO_INVIS) &&
+ !mnt_want_write(file->f_vfsmnt))) {
file_update_time(file);
xfs_ichgtime_fast(xip, inode,
XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
+ mnt_drop_write(file->f_vfsmnt);
}

/*
_