[PATCH] dm: ioctl: add noflush suspend

Provide a dm ioctl option to request noflush suspending.  (See next patch for
what this is for.) As the interface is extended, the version number is
incremented.

Other than accepting the new option through the interface, There is no change
to existing behaviour.

Test results:
Confirmed the option is given from user-space correctly.

Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Cc: dm-devel@redhat.com
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

2 files changed, 5 insertions, 0 deletions

diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c
index 6d7a3d0c8f88..cd6a184536a1 100644
--- a/drivers/md/dm-ioctl.c
+++ b/drivers/md/dm-ioctl.c
@@ -774,6 +774,8 @@ static int do_suspend(struct dm_ioctl *param)
 
         if (param->flags & DM_SKIP_LOCKFS_FLAG)
                 suspend_flags &= ~DM_SUSPEND_LOCKFS_FLAG;
+        if (param->flags & DM_NOFLUSH_FLAG)
+                suspend_flags |= DM_SUSPEND_NOFLUSH_FLAG;
 
         if (!dm_suspended(md))
                 r = dm_suspend(md, suspend_flags);
@@ -815,6 +817,8 @@ static int do_resume(struct dm_ioctl *param)
                 /* Suspend if it isn't already suspended */
                 if (param->flags & DM_SKIP_LOCKFS_FLAG)
                         suspend_flags &= ~DM_SUSPEND_LOCKFS_FLAG;
+                if (param->flags & DM_NOFLUSH_FLAG)
+                        suspend_flags |= DM_SUSPEND_NOFLUSH_FLAG;
                 if (!dm_suspended(md))
                         dm_suspend(md, suspend_flags);
 
diff --git a/drivers/md/dm.h b/drivers/md/dm.h
index 293d5ce62a21..c307ca9a4c33 100644
--- a/drivers/md/dm.h
+++ b/drivers/md/dm.h
@@ -47,6 +47,7 @@
  * Suspend feature flags
  */
 #define DM_SUSPEND_LOCKFS_FLAG          (1 << 0)
+#define DM_SUSPEND_NOFLUSH_FLAG         (1 << 1)
 
 /*
  * List of devices that a metadevice uses and should open/close.