[PATCH v4 1/8] ext4: move out iomap field population into separate helper

[Matthew Bobrowski <mbobrowski@xxxxxxxxxxxxxx>]

Separate the iomap field population chunk into a separate simple
helper routine. This helps reducing the overall clutter within the
ext4_iomap_begin() callback, especially as we move across more code to
make use of iomap infrastructure.

Signed-off-by: Matthew Bobrowski <mbobrowski@xxxxxxxxxxxxxx>
---
 fs/ext4/inode.c | 65 ++++++++++++++++++++++++++++---------------------
 1 file changed, 37 insertions(+), 28 deletions(-)

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 516faa280ced..1ccdc14c4d69 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -3406,10 +3406,43 @@ static bool ext4_inode_datasync_dirty(struct inode *inode)
 	return inode->i_state & I_DIRTY_DATASYNC;
 }
 
+static int ext4_set_iomap(struct inode *inode, struct iomap *iomap, u16 type,
+			  unsigned long first_block, struct ext4_map_blocks *map)
+{
+	u8 blkbits = inode->i_blkbits;
+
+	iomap->flags = 0;
+	if (ext4_inode_datasync_dirty(inode))
+		iomap->flags |= IOMAP_F_DIRTY;
+	iomap->bdev = inode->i_sb->s_bdev;
+	iomap->dax_dev = EXT4_SB(inode->i_sb)->s_daxdev;
+	iomap->offset = (u64) first_block << blkbits;
+	iomap->length = (u64) map->m_len << blkbits;
+
+	if (type) {
+		iomap->type = type;
+		iomap->addr = IOMAP_NULL_ADDR;
+	} else {
+		if (map->m_flags & EXT4_MAP_MAPPED) {
+			iomap->type = IOMAP_MAPPED;
+		} else if (map->m_flags & EXT4_MAP_UNWRITTEN) {
+			iomap->type = IOMAP_UNWRITTEN;
+		} else {
+			WARN_ON_ONCE(1);
+			return -EIO;
+		}
+		iomap->addr = (u64) map->m_pblk << blkbits;
+	}
+
+	if (map->m_flags & EXT4_MAP_NEW)
+		iomap->flags |= IOMAP_F_NEW;
+	return 0;
+}
+
 static int ext4_iomap_begin(struct inode *inode, loff_t offset, loff_t length,
 			    unsigned flags, struct iomap *iomap)
 {
-	struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
+	u16 type = 0;
 	unsigned int blkbits = inode->i_blkbits;
 	unsigned long first_block, last_block;
 	struct ext4_map_blocks map;
@@ -3523,33 +3556,9 @@ static int ext4_iomap_begin(struct inode *inode, loff_t offset, loff_t length,
 			return ret;
 	}
 
-	iomap->flags = 0;
-	if (ext4_inode_datasync_dirty(inode))
-		iomap->flags |= IOMAP_F_DIRTY;
-	iomap->bdev = inode->i_sb->s_bdev;
-	iomap->dax_dev = sbi->s_daxdev;
-	iomap->offset = (u64)first_block << blkbits;
-	iomap->length = (u64)map.m_len << blkbits;
-
-	if (ret == 0) {
-		iomap->type = delalloc ? IOMAP_DELALLOC : IOMAP_HOLE;
-		iomap->addr = IOMAP_NULL_ADDR;
-	} else {
-		if (map.m_flags & EXT4_MAP_MAPPED) {
-			iomap->type = IOMAP_MAPPED;
-		} else if (map.m_flags & EXT4_MAP_UNWRITTEN) {
-			iomap->type = IOMAP_UNWRITTEN;
-		} else {
-			WARN_ON_ONCE(1);
-			return -EIO;
-		}
-		iomap->addr = (u64)map.m_pblk << blkbits;
-	}
-
-	if (map.m_flags & EXT4_MAP_NEW)
-		iomap->flags |= IOMAP_F_NEW;
-
-	return 0;
+	if (!ret)
+		type = delalloc ? IOMAP_DELALLOC : IOMAP_HOLE;
+	return ext4_set_iomap(inode, iomap, type, first_block, &map);
 }
 
 static int ext4_iomap_end(struct inode *inode, loff_t offset, loff_t length,
-- 
2.20.1