Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs

Pull btrfs fixes from Chris Mason:
 "This is an assortment of crash fixes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: stop all workers before cleaning up roots
  Btrfs: fix use-after-free bug during umount
  Btrfs: init relocate extent_io_tree with a mapping
  btrfs: Drop inode if inode root is NULL
  Btrfs: don't delete fs_roots until after we cleanup the transaction

fs/btrfs/disk-io.c

@@ -2859,8 +2859,8 @@ fail_qgroup:
 	btrfs_free_qgroup_config(fs_info);
 fail_trans_kthread:
 	kthread_stop(fs_info->transaction_kthread);
-	del_fs_roots(fs_info);
 	btrfs_cleanup_transaction(fs_info->tree_root);
+	del_fs_roots(fs_info);
 fail_cleaner:
 	kthread_stop(fs_info->cleaner_kthread);
 
@@ -3512,15 +3512,15 @@ int close_ctree(struct btrfs_root *root)
 		       percpu_counter_sum(&fs_info->delalloc_bytes));
 	}
 
-	free_root_pointers(fs_info, 1);
-
 	btrfs_free_block_groups(fs_info);
 
+	btrfs_stop_all_workers(fs_info);
+
 	del_fs_roots(fs_info);
 
-	iput(fs_info->btree_inode);
+	free_root_pointers(fs_info, 1);
 
-	btrfs_stop_all_workers(fs_info);
+	iput(fs_info->btree_inode);
 
 #ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
 	if (btrfs_test_opt(root, CHECK_INTEGRITY))

fs/btrfs/inode.c

@@ -8012,6 +8012,9 @@ int btrfs_drop_inode(struct inode *inode)
 {
 	struct btrfs_root *root = BTRFS_I(inode)->root;
 
+	if (root == NULL)
+		return 1;
+
 	/* the snap/subvol tree is on deleting */
 	if (btrfs_root_refs(&root->root_item) == 0 &&
 	    root != root->fs_info->tree_root)

fs/btrfs/relocation.c

@@ -4082,7 +4082,7 @@ out:
 	return inode;
 }
 
-static struct reloc_control *alloc_reloc_control(void)
+static struct reloc_control *alloc_reloc_control(struct btrfs_fs_info *fs_info)
 {
 	struct reloc_control *rc;
 
@@ -4093,7 +4093,8 @@ static struct reloc_control *alloc_reloc_control(void)
 	INIT_LIST_HEAD(&rc->reloc_roots);
 	backref_cache_init(&rc->backref_cache);
 	mapping_tree_init(&rc->reloc_root_tree);
-	extent_io_tree_init(&rc->processed_blocks, NULL);
+	extent_io_tree_init(&rc->processed_blocks,
+			    fs_info->btree_inode->i_mapping);
 	return rc;
 }
 
@@ -4110,7 +4111,7 @@ int btrfs_relocate_block_group(struct btrfs_root *extent_root, u64 group_start)
 	int rw = 0;
 	int err = 0;
 
-	rc = alloc_reloc_control();
+	rc = alloc_reloc_control(fs_info);
 	if (!rc)
 		return -ENOMEM;
 
@@ -4311,7 +4312,7 @@ int btrfs_recover_relocation(struct btrfs_root *root)
 	if (list_empty(&reloc_roots))
 		goto out;
 
-	rc = alloc_reloc_control();
+	rc = alloc_reloc_control(root->fs_info);
 	if (!rc) {
 		err = -ENOMEM;
 		goto out;