btrfs: don't remove device on a raid0 array when device number is 2

Commit Message

Li Dongyang Dec. 5, 2009, 2:13 p.m. UTC

None

Patch

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 20cbd2e..801b8d0 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -1150,6 +1150,14 @@  int btrfs_rm_device(struct btrfs_root *root, char *device_path)
 		goto out;
 	}
 
+	if ((all_avail & BTRFS_BLOCK_GROUP_RAID0) &&
+	    root->fs_info->fs_devices->rw_devices <= 2) {
+		printk(KERN_ERR "btrfs: unable to go below two "
+		       "devices on raid0\n");
+		ret = -EINVAL;
+		goto out;
+	}
+
 	if (strcmp(device_path, "missing") == 0) {
 		struct list_head *devices;
 		struct btrfs_device *tmp;