dm ioctl: fill in device parameters in more ioctls

Move parameter filling from find_device to __find_device_hash_cell.

This patch causes ioctls using __find_device_hash_cell
(DM_DEV_REMOVE_CMD, DM_DEV_SUSPEND_CMD - resume, DM_TABLE_CLEAR_CMD)
to return device parameters, bringing them into line with the other
ioctls.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>

drivers/md/dm-ioctl.c

@@ -719,36 +719,33 @@ static int dev_create(struct dm_ioctl *param, size_t param_size)
 static struct hash_cell *__find_device_hash_cell(struct dm_ioctl *param)
 {
 	struct mapped_device *md;
-	void *mdptr = NULL;
+	struct hash_cell *hc = NULL;
 
-	if (*param->uuid)
-		return __get_uuid_cell(param->uuid);
+	if (*param->uuid) {
+		hc = __get_uuid_cell(param->uuid);
+		if (!hc)
+			return NULL;
+		goto fill_params;
+	}
 
-	if (*param->name)
-		return __get_name_cell(param->name);
+	if (*param->name) {
+		hc = __get_name_cell(param->name);
+		if (!hc)
+			return NULL;
+		goto fill_params;
+	}
 
 	md = dm_get_md(huge_decode_dev(param->dev));
 	if (!md)
-		goto out;
+		return NULL;
 
-	mdptr = dm_get_mdptr(md);
-	if (!mdptr)
+	hc = dm_get_mdptr(md);
+	if (!hc) {
 		dm_put(md);
+		return NULL;
+	}
 
-out:
-	return mdptr;
-}
-
-static struct mapped_device *find_device(struct dm_ioctl *param)
-{
-	struct hash_cell *hc;
-	struct mapped_device *md = NULL;
-
-	down_read(&_hash_lock);
-	hc = __find_device_hash_cell(param);
-	if (hc) {
-		md = hc->md;
-
+fill_params:
 	/*
 	 * Sneakily write in both the name and the uuid
 	 * while we have the cell.
@@ -763,7 +760,19 @@ static struct mapped_device *find_device(struct dm_ioctl *param)
 		param->flags |= DM_INACTIVE_PRESENT_FLAG;
 	else
 		param->flags &= ~DM_INACTIVE_PRESENT_FLAG;
-	}
+
+	return hc;
+}
+
+static struct mapped_device *find_device(struct dm_ioctl *param)
+{
+	struct hash_cell *hc;
+	struct mapped_device *md = NULL;
+
+	down_read(&_hash_lock);
+	hc = __find_device_hash_cell(param);
+	if (hc)
+		md = hc->md;
 	up_read(&_hash_lock);
 
 	return md;

include/linux/dm-ioctl.h

@@ -267,9 +267,9 @@ 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	20
+#define DM_VERSION_MINOR	21
 #define DM_VERSION_PATCHLEVEL	0
-#define DM_VERSION_EXTRA	"-ioctl (2011-02-02)"
+#define DM_VERSION_EXTRA	"-ioctl (2011-07-06)"
 
 /* Status bits */
 #define DM_READONLY_FLAG	(1 << 0) /* In/Out */