[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>

3 files changed, 12 insertions, 2 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.
diff --git a/include/linux/dm-ioctl.h b/include/linux/dm-ioctl.h
index 8853fc4d1c5e..b93486107821 100644
--- a/include/linux/dm-ioctl.h
+++ b/include/linux/dm-ioctl.h
@@ -285,9 +285,9 @@ typedef char ioctl_struct[308];
 #define DM_DEV_SET_GEOMETRY     _IOWR(DM_IOCTL, DM_DEV_SET_GEOMETRY_CMD, struct dm_ioctl)
 
 #define DM_VERSION_MAJOR        4
-#define DM_VERSION_MINOR        10
+#define DM_VERSION_MINOR        11
 #define DM_VERSION_PATCHLEVEL   0
-#define DM_VERSION_EXTRA        "-ioctl (2006-09-14)"
+#define DM_VERSION_EXTRA        "-ioctl (2006-10-12)"
 
 /* Status bits */
 #define DM_READONLY_FLAG        (1 << 0) /* In/Out */
@@ -323,4 +323,9 @@ typedef char ioctl_struct[308];
  */
 #define DM_SKIP_LOCKFS_FLAG     (1 << 10) /* In */
 
+/*
+ * Set this to suspend without flushing queued ios.
+ */
+#define DM_NOFLUSH_FLAG         (1 << 11) /* In */
+
 #endif                          /* _LINUX_DM_IOCTL_H */