btrfs: use single variable to track return value at btrfs_log_inode()

At btrfs_log_inode(), we have two variables to track errors and the
return value of the function, named 'ret' and 'err'. In some places we
use 'ret' and if gets a non-zero value we assign its value to 'err'
and then jump to the 'out' label, while in other places we use 'err'
directly without 'ret' as an intermediary. This is inconsistent, error
prone and not necessary. So change that to use only the 'ret' variable,
making this consistent with most functions in btrfs.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

fs/btrfs/tree-log.c

@@ -5702,8 +5702,7 @@ static int btrfs_log_inode(struct btrfs_trans_handle *trans,
 	struct btrfs_key min_key;
 	struct btrfs_key max_key;
 	struct btrfs_root *log = inode->root->log_root;
-	int err = 0;
-	int ret = 0;
+	int ret;
 	bool fast_search = false;
 	u64 ino = btrfs_ino(inode);
 	struct extent_map_tree *em_tree = &inode->extent_tree;
@@ -5746,8 +5745,8 @@ static int btrfs_log_inode(struct btrfs_trans_handle *trans,
 	 * and figure out which index ranges have to be logged.
 	 */
 	if (S_ISDIR(inode->vfs_inode.i_mode)) {
-		err = btrfs_commit_inode_delayed_items(trans, inode);
-		if (err)
+		ret = btrfs_commit_inode_delayed_items(trans, inode);
+		if (ret)
 			goto out;
 	}
 
@@ -5768,11 +5767,10 @@ static int btrfs_log_inode(struct btrfs_trans_handle *trans,
 	 * the inode was previously logged in this transaction.
 	 */
 	ret = inode_logged(trans, inode, path);
-	if (ret < 0) {
-		err = ret;
+	if (ret < 0)
 		goto out_unlock;
-	}
 	ctx->logged_before = (ret == 1);
+	ret = 0;
 
 	/*
 	 * This is for cases where logging a directory could result in losing a
@@ -5785,7 +5783,7 @@ static int btrfs_log_inode(struct btrfs_trans_handle *trans,
 	    inode_only == LOG_INODE_ALL &&
 	    inode->last_unlink_trans >= trans->transid) {
 		btrfs_set_log_full_commit(trans);
-		err = 1;
+		ret = 1;
 		goto out_unlock;
 	}
 
@@ -5817,8 +5815,8 @@ static int btrfs_log_inode(struct btrfs_trans_handle *trans,
 			 * (zeroes), as if an expanding truncate happened,
 			 * instead of getting a file of 4Kb only.
 			 */
-			err = logged_inode_size(log, inode, path, &logged_isize);
-			if (err)
+			ret = logged_inode_size(log, inode, path, &logged_isize);
+			if (ret)
 				goto out_unlock;
 		}
 		if (test_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
@@ -5854,37 +5852,35 @@ static int btrfs_log_inode(struct btrfs_trans_handle *trans,
 		}
 
 	}
-	if (ret) {
-		err = ret;
+	if (ret)
 		goto out_unlock;
-	}
 
-	err = copy_inode_items_to_log(trans, inode, &min_key, &max_key,
+	ret = copy_inode_items_to_log(trans, inode, &min_key, &max_key,
 				      path, dst_path, logged_isize,
 				      recursive_logging, inode_only, ctx,
 				      &need_log_inode_item);
-	if (err)
+	if (ret)
 		goto out_unlock;
 
 	btrfs_release_path(path);
 	btrfs_release_path(dst_path);
-	err = btrfs_log_all_xattrs(trans, inode, path, dst_path);
-	if (err)
+	ret = btrfs_log_all_xattrs(trans, inode, path, dst_path);
+	if (ret)
 		goto out_unlock;
 	xattrs_logged = true;
 	if (max_key.type >= BTRFS_EXTENT_DATA_KEY && !fast_search) {
 		btrfs_release_path(path);
 		btrfs_release_path(dst_path);
-		err = btrfs_log_holes(trans, inode, path);
-		if (err)
+		ret = btrfs_log_holes(trans, inode, path);
+		if (ret)
 			goto out_unlock;
 	}
 log_extents:
 	btrfs_release_path(path);
 	btrfs_release_path(dst_path);
 	if (need_log_inode_item) {
-		err = log_inode_item(trans, log, dst_path, inode, inode_item_dropped);
-		if (err)
+		ret = log_inode_item(trans, log, dst_path, inode, inode_item_dropped);
+		if (ret)
 			goto out_unlock;
 		/*
 		 * If we are doing a fast fsync and the inode was logged before
@@ -5895,18 +5891,16 @@ static int btrfs_log_inode(struct btrfs_trans_handle *trans,
 		 * BTRFS_INODE_COPY_EVERYTHING set.
 		 */
 		if (!xattrs_logged && inode->logged_trans < trans->transid) {
-			err = btrfs_log_all_xattrs(trans, inode, path, dst_path);
-			if (err)
+			ret = btrfs_log_all_xattrs(trans, inode, path, dst_path);
+			if (ret)
 				goto out_unlock;
 			btrfs_release_path(path);
 		}
 	}
 	if (fast_search) {
 		ret = btrfs_log_changed_extents(trans, inode, dst_path, ctx);
-		if (ret) {
-			err = ret;
+		if (ret)
 			goto out_unlock;
-		}
 	} else if (inode_only == LOG_INODE_ALL) {
 		struct extent_map *em, *n;
 
@@ -5918,10 +5912,8 @@ static int btrfs_log_inode(struct btrfs_trans_handle *trans,
 
 	if (inode_only == LOG_INODE_ALL && S_ISDIR(inode->vfs_inode.i_mode)) {
 		ret = log_directory_changes(trans, inode, path, dst_path, ctx);
-		if (ret) {
-			err = ret;
+		if (ret)
 			goto out_unlock;
-		}
 	}
 
 	spin_lock(&inode->lock);
@@ -5969,7 +5961,7 @@ static int btrfs_log_inode(struct btrfs_trans_handle *trans,
 	if (recursive_logging)
 		ctx->logged_before = orig_logged_before;
 
-	return err;
+	return ret;
 }
 
 /*