5 files changed, 34 insertions, 6 deletions

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 5611f8e035a4..b3bc65b08c6a 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -799,6 +799,12 @@ struct btrfs_root {
         spinlock_t list_lock;
         struct list_head dead_list;
         struct list_head orphan_list;
+
+        /*
+         * right now this just gets used so that a root has its own devid
+         * for stat.  It may be used for more later
+         */
+        struct super_block anon_super;
 };
 
 /*
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 0a5350573f61..8d7866b733d6 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -877,6 +877,12 @@ static int __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize,
         root->defrag_running = 0;
         root->defrag_level = 0;
         root->root_key.objectid = objectid;
+        root->anon_super.s_root = NULL;
+        root->anon_super.s_dev = 0;
+        INIT_LIST_HEAD(&root->anon_super.s_list);
+        INIT_LIST_HEAD(&root->anon_super.s_instances);
+        init_rwsem(&root->anon_super.s_umount);
+
         return 0;
 }
 
@@ -1083,6 +1089,9 @@ struct btrfs_root *btrfs_read_fs_root_no_name(struct btrfs_fs_info *fs_info,
         root = btrfs_read_fs_root_no_radix(fs_info->tree_root, location);
         if (IS_ERR(root))
                 return root;
+
+        set_anon_super(&root->anon_super, NULL);
+
         ret = radix_tree_insert(&fs_info->fs_roots_radix,
                                 (unsigned long)root->root_key.objectid,
                                 root);
@@ -1950,6 +1959,10 @@ int btrfs_free_fs_root(struct btrfs_fs_info *fs_info, struct btrfs_root *root)
 {
         radix_tree_delete(&fs_info->fs_roots_radix,
                           (unsigned long)root->root_key.objectid);
+        if (root->anon_super.s_dev) {
+                down_write(&root->anon_super.s_umount);
+                kill_anon_super(&root->anon_super);
+        }
         if (root->in_sysfs)
                 btrfs_sysfs_del_root(root);
         if (root->node)
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index e163b1b74707..7ef79ce86e25 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -2212,7 +2212,12 @@ static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
         struct btrfs_trans_handle *trans;
         unsigned long nr = 0;
 
-        if (inode->i_size > BTRFS_EMPTY_DIR_SIZE) {
+        /*
+         * the FIRST_FREE_OBJECTID check makes sure we don't try to rmdir
+         * the root of a subvolume or snapshot
+         */
+        if (inode->i_size > BTRFS_EMPTY_DIR_SIZE ||
+            inode->i_ino == BTRFS_FIRST_FREE_OBJECTID) {
                 return -ENOTEMPTY;
         }
 
@@ -4410,7 +4415,6 @@ int btrfs_create_subvol_root(struct btrfs_root *new_root, struct dentry *dentry,
         if (error)
                 return error;
 
-        atomic_inc(&inode->i_count);
         d_instantiate(dentry, inode);
         return 0;
 }
@@ -4548,6 +4552,7 @@ static int btrfs_getattr(struct vfsmount *mnt,
 {
         struct inode *inode = dentry->d_inode;
         generic_fillattr(inode, stat);
+        stat->dev = BTRFS_I(inode)->root->anon_super.s_dev;
         stat->blksize = PAGE_CACHE_SIZE;
         stat->blocks = (inode_get_bytes(inode) +
                         BTRFS_I(inode)->delalloc_bytes) >> 9;
@@ -4565,6 +4570,11 @@ static int btrfs_rename(struct inode * old_dir, struct dentry *old_dentry,
         u64 index = 0;
         int ret;
 
+        /* we're not allowed to rename between subvolumes */
+        if (BTRFS_I(old_inode)->root->root_key.objectid !=
+            BTRFS_I(new_dir)->root->root_key.objectid)
+                return -EXDEV;
+
         if (S_ISDIR(old_inode->i_mode) && new_inode &&
             new_inode->i_size > BTRFS_EMPTY_DIR_SIZE) {
                 return -ENOTEMPTY;
@@ -4920,6 +4930,7 @@ static int btrfs_permission(struct inode *inode, int mask)
 }
 
 static struct inode_operations btrfs_dir_inode_operations = {
+        .getattr        = btrfs_getattr,
         .lookup         = btrfs_lookup,
         .create         = btrfs_create,
         .unlink         = btrfs_unlink,
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index ec45b3086136..773db07b5f72 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -127,7 +127,6 @@ static noinline int create_subvol(struct btrfs_root *root,
         key.objectid = objectid;
         key.offset = 1;
         btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
-printk("inserting root objectid %Lu\n", objectid);
         ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
                                 &root_item);
         if (ret)
@@ -175,7 +174,6 @@ fail:
                 ret = err;
 fail_commit:
         btrfs_btree_balance_dirty(root, nr);
-printk("all done ret %d\n", ret);
         return ret;
 }
 
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index eec8b2465039..93f23a456a36 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -832,13 +832,13 @@ static noinline int finish_pending_snapshot(struct btrfs_fs_info *fs_info,
         struct inode *parent_inode;
         struct inode *inode;
 
-        trans = btrfs_start_transaction(fs_info->fs_root, 1);
+        parent_inode = pending->dentry->d_parent->d_inode;
+        trans = btrfs_start_transaction(BTRFS_I(parent_inode)->root, 1);
 
         /*
          * insert the directory item
          */
         namelen = strlen(pending->name);
-        parent_inode = pending->dentry->d_parent->d_inode;
         ret = btrfs_set_inode_index(parent_inode, &index);
         ret = btrfs_insert_dir_item(trans,
                             BTRFS_I(parent_inode)->root,