fs/buffer: Remove redundant assignment to err

Variable 'err' set but not used.

fs/buffer.c:2613:2: warning: Value stored to 'err' is never read.

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Link: https://bugzilla.openanolis.cn/show_bug.cgi?id=4589
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>

fs/buffer.c

@@ -2581,7 +2581,7 @@ int block_truncate_page(struct address_space *mapping,
 	struct inode *inode = mapping->host;
 	struct page *page;
 	struct buffer_head *bh;
-	int err;
+	int err = 0;
 
 	blocksize = i_blocksize(inode);
 	length = offset & (blocksize - 1);
@@ -2594,9 +2594,8 @@ int block_truncate_page(struct address_space *mapping,
 	iblock = (sector_t)index << (PAGE_SHIFT - inode->i_blkbits);
 
 	page = grab_cache_page(mapping, index);
-	err = -ENOMEM;
 	if (!page)
-		goto out;
+		return -ENOMEM;
 
 	if (!page_has_buffers(page))
 		create_empty_buffers(page, blocksize, 0);
@@ -2610,7 +2609,6 @@ int block_truncate_page(struct address_space *mapping,
 		pos += blocksize;
 	}
 
-	err = 0;
 	if (!buffer_mapped(bh)) {
 		WARN_ON(bh->b_size != blocksize);
 		err = get_block(inode, iblock, bh, 0);
@@ -2634,12 +2632,11 @@ int block_truncate_page(struct address_space *mapping,
 
 	zero_user(page, offset, length);
 	mark_buffer_dirty(bh);
-	err = 0;
 
 unlock:
 	unlock_page(page);
 	put_page(page);
-out:
+
 	return err;
 }
 EXPORT_SYMBOL(block_truncate_page);