4 files changed, 43 insertions, 13 deletions

diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c
index 1128d3fba797..1c871736f48c 100644
--- a/drivers/md/dm-ioctl.c
+++ b/drivers/md/dm-ioctl.c
@@ -276,7 +276,7 @@ retry:
         up_write(&_hash_lock);
 }
 
-static int dm_hash_rename(const char *old, const char *new)
+static int dm_hash_rename(uint32_t cookie, const char *old, const char *new)
 {
         char *new_name, *old_name;
         struct hash_cell *hc;
@@ -333,7 +333,7 @@ static int dm_hash_rename(const char *old, const char *new)
                 dm_table_put(table);
         }
 
-        dm_kobject_uevent(hc->md);
+        dm_kobject_uevent(hc->md, KOBJ_CHANGE, cookie);
 
         dm_put(hc->md);
         up_write(&_hash_lock);
@@ -680,6 +680,9 @@ static int dev_remove(struct dm_ioctl *param, size_t param_size)
 
         __hash_remove(hc);
         up_write(&_hash_lock);
+
+        dm_kobject_uevent(md, KOBJ_REMOVE, param->event_nr);
+
         dm_put(md);
         param->data_size = 0;
         return 0;
@@ -715,7 +718,7 @@ static int dev_rename(struct dm_ioctl *param, size_t param_size)
                 return r;
 
         param->data_size = 0;
-        return dm_hash_rename(param->name, new_name);
+        return dm_hash_rename(param->event_nr, param->name, new_name);
 }
 
 static int dev_set_geometry(struct dm_ioctl *param, size_t param_size)
@@ -842,8 +845,11 @@ static int do_resume(struct dm_ioctl *param)
         if (dm_suspended(md))
                 r = dm_resume(md);
 
-        if (!r)
+
+        if (!r) {
+                dm_kobject_uevent(md, KOBJ_CHANGE, param->event_nr);
                 r = __dev_status(md, param);
+        }
 
         dm_put(md);
         return r;
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 36142e947ffc..a9210bb594e7 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -24,6 +24,13 @@
 
 #define DM_MSG_PREFIX "core"
 
+/*
+ * Cookies are numeric values sent with CHANGE and REMOVE
+ * uevents while resuming, removing or renaming the device.
+ */
+#define DM_COOKIE_ENV_VAR_NAME "DM_COOKIE"
+#define DM_COOKIE_LENGTH 24
+
 static const char *_name = DM_NAME;
 
 static unsigned int major = 0;
@@ -1731,11 +1738,7 @@ int dm_resume(struct mapped_device *md)
         clear_bit(DMF_SUSPENDED, &md->flags);
 
         dm_table_unplug_all(map);
-
-        dm_kobject_uevent(md);
-
         r = 0;
-
 out:
         dm_table_put(map);
         mutex_unlock(&md->suspend_lock);
@@ -1746,9 +1749,19 @@ out:
 /*-----------------------------------------------------------------
  * Event notification.
  *---------------------------------------------------------------*/
-void dm_kobject_uevent(struct mapped_device *md)
+void dm_kobject_uevent(struct mapped_device *md, enum kobject_action action,
+                       unsigned cookie)
 {
-        kobject_uevent(&disk_to_dev(md->disk)->kobj, KOBJ_CHANGE);
+        char udev_cookie[DM_COOKIE_LENGTH];
+        char *envp[] = { udev_cookie, NULL };
+
+        if (!cookie)
+                kobject_uevent(&disk_to_dev(md->disk)->kobj, action);
+        else {
+                snprintf(udev_cookie, DM_COOKIE_LENGTH, "%s=%u",
+                         DM_COOKIE_ENV_VAR_NAME, cookie);
+                kobject_uevent_env(&disk_to_dev(md->disk)->kobj, action, envp);
+        }
 }
 
 uint32_t dm_next_uevent_seq(struct mapped_device *md)
diff --git a/drivers/md/dm.h b/drivers/md/dm.h
index a31506d93e91..b5935c610c44 100644
--- a/drivers/md/dm.h
+++ b/drivers/md/dm.h
@@ -92,7 +92,8 @@ void dm_stripe_exit(void);
 int dm_open_count(struct mapped_device *md);
 int dm_lock_for_deletion(struct mapped_device *md);
 
-void dm_kobject_uevent(struct mapped_device *md);
+void dm_kobject_uevent(struct mapped_device *md, enum kobject_action action,
+                       unsigned cookie);
 
 int dm_kcopyd_init(void);
 void dm_kcopyd_exit(void);
diff --git a/include/linux/dm-ioctl.h b/include/linux/dm-ioctl.h
index 48e44ee2b466..2ab84c83c31a 100644
--- a/include/linux/dm-ioctl.h
+++ b/include/linux/dm-ioctl.h
@@ -123,6 +123,16 @@ struct dm_ioctl {
         __u32 target_count;     /* in/out */
         __s32 open_count;       /* out */
         __u32 flags;            /* in/out */
+
+        /*
+         * event_nr holds either the event number (input and output) or the
+         * udev cookie value (input only).
+         * The DM_DEV_WAIT ioctl takes an event number as input.
+         * The DM_SUSPEND, DM_DEV_REMOVE and DM_DEV_RENAME ioctls
+         * use the field as a cookie to return in the DM_COOKIE
+         * variable with the uevents they issue.
+         * For output, the ioctls return the event number, not the cookie.
+         */
         __u32 event_nr;         /* in/out */
         __u32 padding;
 
@@ -256,9 +266,9 @@ enum {
 #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        14
+#define DM_VERSION_MINOR        15
 #define DM_VERSION_PATCHLEVEL   0
-#define DM_VERSION_EXTRA        "-ioctl (2008-04-23)"
+#define DM_VERSION_EXTRA        "-ioctl (2009-04-01)"
 
 /* Status bits */
 #define DM_READONLY_FLAG        (1 << 0) /* In/Out */