[RFC PATCH v2 01/25] ext4: refactor ext4_da_map_blocks()

[Zhang Yi <yi.zhang@huaweicloud.com>]

From: Zhang Yi <yi.zhang@huawei.com>

Refactor and cleanup ext4_da_map_blocks(), reduce some unnecessary
parameters and branches, no logic changes.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
---
 fs/ext4/inode.c | 39 +++++++++++++++++----------------------
 1 file changed, 17 insertions(+), 22 deletions(-)

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 61277f7f8722..5b0d3075be12 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -1704,7 +1704,6 @@ static int ext4_da_map_blocks(struct inode *inode, sector_t iblock,
 	/* Lookup extent status tree firstly */
 	if (ext4_es_lookup_extent(inode, iblock, NULL, &es)) {
 		if (ext4_es_is_hole(&es)) {
-			retval = 0;
 			down_read(&EXT4_I(inode)->i_data_sem);
 			goto add_delayed;
 		}
@@ -1749,26 +1748,9 @@ static int ext4_da_map_blocks(struct inode *inode, sector_t iblock,
 		retval = ext4_ext_map_blocks(NULL, inode, map, 0);
 	else
 		retval = ext4_ind_map_blocks(NULL, inode, map, 0);
-
-add_delayed:
-	if (retval == 0) {
-		int ret;
-
-		/*
-		 * XXX: __block_prepare_write() unmaps passed block,
-		 * is it OK?
-		 */
-
-		ret = ext4_insert_delayed_block(inode, map->m_lblk);
-		if (ret != 0) {
-			retval = ret;
-			goto out_unlock;
-		}
-
-		map_bh(bh, inode->i_sb, invalid_block);
-		set_buffer_new(bh);
-		set_buffer_delay(bh);
-	} else if (retval > 0) {
+	if (retval < 0)
+		goto out_unlock;
+	if (retval > 0) {
 		unsigned int status;
 
 		if (unlikely(retval != map->m_len)) {
@@ -1783,11 +1765,24 @@ static int ext4_da_map_blocks(struct inode *inode, sector_t iblock,
 				EXTENT_STATUS_UNWRITTEN : EXTENT_STATUS_WRITTEN;
 		ext4_es_insert_extent(inode, map->m_lblk, map->m_len,
 				      map->m_pblk, status);
+		goto out_unlock;
 	}
 
+add_delayed:
+	/*
+	 * XXX: __block_prepare_write() unmaps passed block,
+	 * is it OK?
+	 */
+	retval = ext4_insert_delayed_block(inode, map->m_lblk);
+	if (retval)
+		goto out_unlock;
+
+	map_bh(bh, inode->i_sb, invalid_block);
+	set_buffer_new(bh);
+	set_buffer_delay(bh);
+
 out_unlock:
 	up_read((&EXT4_I(inode)->i_data_sem));
-
 	return retval;
 }
 
-- 
2.39.2