Btrfs: Pass transaction handle to security and ACL initialization functions

Pass transaction handle down to security and ACL initialization
functions, so we can avoid starting nested transactions

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 54 insertions, 26 deletions

diff --git a/fs/btrfs/xattr.c b/fs/btrfs/xattr.c
index b6dd596..193b58f 100644
--- a/fs/btrfs/xattr.c
+++ b/fs/btrfs/xattr.c
@@ -85,22 +85,23 @@ out:
 	return ret;
 }
 
-int __btrfs_setxattr(struct inode *inode, const char *name,
-			    const void *value, size_t size, int flags)
+static int do_setxattr(struct btrfs_trans_handle *trans,
+		       struct inode *inode, const char *name,
+		       const void *value, size_t size, int flags)
 {
 	struct btrfs_dir_item *di;
 	struct btrfs_root *root = BTRFS_I(inode)->root;
-	struct btrfs_trans_handle *trans;
 	struct btrfs_path *path;
-	int ret = 0, mod = 0;
+	size_t name_len = strlen(name);
+	int ret = 0;
+
+	if (name_len + size > BTRFS_MAX_XATTR_SIZE(root))
+		return -ENOSPC;
 
 	path = btrfs_alloc_path();
 	if (!path)
 		return -ENOMEM;
 
-	trans = btrfs_join_transaction(root, 1);
-	btrfs_set_trans_block_group(trans, inode);
-
 	/* first lets see if we already have this xattr */
 	di = btrfs_lookup_xattr(trans, root, path, inode->i_ino, name,
 				strlen(name), -1);
@@ -118,15 +119,12 @@ int __btrfs_setxattr(struct inode *inode, const char *name,
 		}
 
 		ret = btrfs_delete_one_dir_name(trans, root, path, di);
-		if (ret)
-			goto out;
+		BUG_ON(ret);
 		btrfs_release_path(root, path);
 
 		/* if we don't have a value then we are removing the xattr */
-		if (!value) {
-			mod = 1;
+		if (!value)
 			goto out;
-		}
 	} else {
 		btrfs_release_path(root, path);
 
@@ -138,20 +136,45 @@ int __btrfs_setxattr(struct inode *inode, const char *name,
 	}
 
 	/* ok we have to create a completely new xattr */
-	ret = btrfs_insert_xattr_item(trans, root, name, strlen(name),
-				      value, size, inode->i_ino);
+	ret = btrfs_insert_xattr_item(trans, root, path, inode->i_ino,
+				      name, name_len, value, size);
+	BUG_ON(ret);
+out:
+	btrfs_free_path(path);
+	return ret;
+}
+
+int __btrfs_setxattr(struct btrfs_trans_handle *trans,
+		     struct inode *inode, const char *name,
+		     const void *value, size_t size, int flags)
+{
+	struct btrfs_root *root = BTRFS_I(inode)->root;
+	int ret;
+
+	if (trans)
+		return do_setxattr(trans, inode, name, value, size, flags);
+
+	ret = btrfs_reserve_metadata_space(root, 2);
 	if (ret)
-		goto out;
-	mod = 1;
+		return ret;
 
-out:
-	if (mod) {
-		inode->i_ctime = CURRENT_TIME;
-		ret = btrfs_update_inode(trans, root, inode);
+	trans = btrfs_start_transaction(root, 1);
+	if (!trans) {
+		ret = -ENOMEM;
+		goto out;
 	}
+	btrfs_set_trans_block_group(trans, inode);
 
-	btrfs_end_transaction(trans, root);
-	btrfs_free_path(path);
+	ret = do_setxattr(trans, inode, name, value, size, flags);
+	if (ret)
+		goto out;
+
+	inode->i_ctime = CURRENT_TIME;
+	ret = btrfs_update_inode(trans, root, inode);
+	BUG_ON(ret);
+out:
+	btrfs_end_transaction_throttle(trans, root);
+	btrfs_unreserve_metadata_space(root, 2);
 	return ret;
 }
 
@@ -314,7 +337,9 @@ int btrfs_setxattr(struct dentry *dentry, const char *name, const void *value,
 
 	if (size == 0)
 		value = "";  /* empty EA, do not remove */
-	return __btrfs_setxattr(dentry->d_inode, name, value, size, flags);
+
+	return __btrfs_setxattr(NULL, dentry->d_inode, name, value, size,
+				flags);
 }
 
 int btrfs_removexattr(struct dentry *dentry, const char *name)
@@ -329,10 +354,13 @@ int btrfs_removexattr(struct dentry *dentry, const char *name)
 
 	if (!btrfs_is_valid_xattr(name))
 		return -EOPNOTSUPP;
-	return __btrfs_setxattr(dentry->d_inode, name, NULL, 0, XATTR_REPLACE);
+
+	return __btrfs_setxattr(NULL, dentry->d_inode, name, NULL, 0,
+				XATTR_REPLACE);
 }
 
-int btrfs_xattr_security_init(struct inode *inode, struct inode *dir)
+int btrfs_xattr_security_init(struct btrfs_trans_handle *trans,
+			      struct inode *inode, struct inode *dir)
 {
 	int err;
 	size_t len;
@@ -354,7 +382,7 @@ int btrfs_xattr_security_init(struct inode *inode, struct inode *dir)
 	} else {
 		strcpy(name, XATTR_SECURITY_PREFIX);
 		strcpy(name + XATTR_SECURITY_PREFIX_LEN, suffix);
-		err = __btrfs_setxattr(inode, name, value, len, 0);
+		err = __btrfs_setxattr(trans, inode, name, value, len, 0);
 		kfree(name);
 	}