From 4eb150d6122bf51744d07c569ea811e8ce4bdd6d Mon Sep 17 00:00:00 2001
From: Qu Wenruo <wqu@suse.com>
Date: Tue, 22 Feb 2022 15:41:19 +0800
Subject: btrfs: unify the error handling pattern for read_tree_block()

We had an error handling pattern for read_tree_block() like this:

	eb = read_tree_block();
	if (IS_ERR(eb)) {
		/*
		 * Handling error here
		 * Normally ended up with return or goto out.
		 */
	} else if (!extent_buffer_uptodate(eb)) {
		/*
		 * Different error handling here
		 * Normally also ended up with return or goto out;
		 */
	}

This is fine, but if we want to add extra check for each
read_tree_block(), the existing if-else-if is not that expandable and
will take reader some seconds to figure out there is no extra branch.

Here we change it to a more common way, without the extra else:

	eb = read_tree_block();
	if (IS_ERR(eb)) {
		/*
		 * Handling error here
		 */
		return eb or goto out;
	}
	if (!extent_buffer_uptodate(eb)) {
		/*
		 * Different error handling here
		 */
		return eb or goto out;
	}

This also removes some oddball call sites which uses some creative way
to check error.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
---
 fs/btrfs/backref.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

(limited to 'fs/btrfs/backref.c')

diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c
index c9ee579bc5a6..ebc392ea1d74 100644
--- a/fs/btrfs/backref.c
+++ b/fs/btrfs/backref.c
@@ -789,11 +789,13 @@ static int add_missing_keys(struct btrfs_fs_info *fs_info,
 		if (IS_ERR(eb)) {
 			free_pref(ref);
 			return PTR_ERR(eb);
-		} else if (!extent_buffer_uptodate(eb)) {
+		}
+		if (!extent_buffer_uptodate(eb)) {
 			free_pref(ref);
 			free_extent_buffer(eb);
 			return -EIO;
 		}
+
 		if (lock)
 			btrfs_tree_read_lock(eb);
 		if (btrfs_header_level(eb) == 0)
@@ -1335,7 +1337,8 @@ again:
 				if (IS_ERR(eb)) {
 					ret = PTR_ERR(eb);
 					goto out;
-				} else if (!extent_buffer_uptodate(eb)) {
+				}
+				if (!extent_buffer_uptodate(eb)) {
 					free_extent_buffer(eb);
 					ret = -EIO;
 					goto out;
-- 
cgit v1.2.3