Btrfs: make the logic of source device removing more clear

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>

fs/btrfs/dev-replace.c

diff --git a/fs/btrfs/dev-replace.c b/fs/btrfs/dev-replace.c
index e9cbbdb..6f662b3 100644
--- a/fs/btrfs/dev-replace.c
+++ b/fs/btrfs/dev-replace.c
@@ -569,8 +569,7 @@
 	if (fs_info->fs_devices->latest_bdev == src_device->bdev)
 		fs_info->fs_devices->latest_bdev = tgt_device->bdev;
 	list_add(&tgt_device->dev_alloc_list, &fs_info->fs_devices->alloc_list);
-	if (src_device->fs_devices->seeding)
-		fs_info->fs_devices->rw_devices++;
+	fs_info->fs_devices->rw_devices++;
 
 	/* replace the sysfs entry */
 	btrfs_kobj_rm_device(fs_info, src_device);

fs/btrfs/volumes.c

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index a15c8ac..2e078fa 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -1819,23 +1819,18 @@
 	list_del_rcu(&srcdev->dev_list);
 	list_del_rcu(&srcdev->dev_alloc_list);
 	fs_devices->num_devices--;
-	if (srcdev->missing) {
+	if (srcdev->missing)
 		fs_devices->missing_devices--;
-		if (!fs_devices->seeding)
-			fs_devices->rw_devices++;
+
+	if (srcdev->writeable) {
+		fs_devices->rw_devices--;
+		/* zero out the old super if it is writable */
+		btrfs_scratch_superblock(srcdev);
 	}
 
-	if (srcdev->bdev) {
+	if (srcdev->bdev)
 		fs_devices->open_devices--;
 
-		/*
-		 * zero out the old super if it is not writable
-		 * (e.g. seed device)
-		 */
-		if (srcdev->writeable)
-			btrfs_scratch_superblock(srcdev);
-	}
-
 	call_rcu(&srcdev->rcu, free_device);
 
 	/*