[PATCH v5 4/4] btrfs: use dev_t to match device in device_matched

[Anand Jain <anand.jain@oracle.com>]

Commit 6531891b2bcb ("btrfs: add device major-minor info in the struct
btrfs_device") saved the device major-minor number in the struct
btrfs_device upon discovering it.

So no need to lookup_bdev() again just match, which means
device_matched() can go away.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
---
v5: -
v4: -
v3: -

 fs/btrfs/volumes.c | 42 +-----------------------------------------
 1 file changed, 1 insertion(+), 41 deletions(-)

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 5044b8f9cfff..87d53b3a3377 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -535,46 +535,6 @@ btrfs_get_bdev_and_sb(const char *device_path, fmode_t flags, void *holder,
 	return ret;
 }
 
-/*
- * Check if the device in the 'path' matches with the device in the given
- * struct btrfs_device '*device'.
- * Returns:
- *   true  If it is the same device.
- *   false If it is not the same device or on error.
- */
-static bool device_matched(struct btrfs_device *device, dev_t dev_new)
-{
-	char *device_name;
-	dev_t dev_old;
-	int ret;
-
-	/*
-	 * If we are looking for a device with the matching dev_t, then skip
-	 * device without a name (a missing device).
-	 */
-	if (!device->name)
-		return false;
-
-	device_name = kzalloc(BTRFS_PATH_NAME_MAX, GFP_KERNEL);
-	if (!device_name)
-		return false;
-
-	rcu_read_lock();
-	scnprintf(device_name, BTRFS_PATH_NAME_MAX, "%s",
-		  rcu_str_deref(device->name));
-	rcu_read_unlock();
-
-	ret = lookup_bdev(device_name, &dev_old);
-	kfree(device_name);
-	if (ret)
-		return false;
-
-	if (dev_old == dev_new)
-		return true;
-
-	return false;
-}
-
 /*
  *  Search and remove all stale (devices which are not mounted) devices.
  *  When both inputs are NULL, it will search and release all stale devices.
@@ -605,7 +565,7 @@ static int btrfs_free_stale_devices(dev_t devt,
 					 &fs_devices->devices, dev_list) {
 			if (skip_device && skip_device == device)
 				continue;
-			if (devt && device_matched(device, devt) == false)
+			if (devt && devt != device->devt)
 				continue;
 			if (fs_devices->opened) {
 				/* for an already deleted device return 0 */
-- 
2.33.1