btrfs: pass the new logical address to split_extent_map

split_extent_map splits off the first chunk of an extent map into a new
one.  One of the two users is the zoned I/O completion code that wants to
rewrite the logical block start address right after this split.  Pass in
the logical address to be set in the split off first extent_map as an
argument to avoid an extra extent tree lookup for this case.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>

4 files changed, 11 insertions, 9 deletions

diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c
index e5124461ea02..0cdb3e86f29b 100644
--- a/fs/btrfs/extent_map.c
+++ b/fs/btrfs/extent_map.c
@@ -963,11 +963,13 @@ int btrfs_replace_extent_map_range(struct btrfs_inode *inode,
 }
 
 /*
- * Split off the first pre bytes from the extent_map at [start, start + len]
+ * Split off the first pre bytes from the extent_map at [start, start + len],
+ * and set the block_start for it to new_logical.
  *
  * This function is used when an ordered_extent needs to be split.
  */
-int split_extent_map(struct btrfs_inode *inode, u64 start, u64 len, u64 pre)
+int split_extent_map(struct btrfs_inode *inode, u64 start, u64 len, u64 pre,
+		     u64 new_logical)
 {
 	struct extent_map_tree *em_tree = &inode->extent_tree;
 	struct extent_map *em;
@@ -1010,7 +1012,7 @@ int split_extent_map(struct btrfs_inode *inode, u64 start, u64 len, u64 pre)
 	split_pre->start = em->start;
 	split_pre->len = pre;
 	split_pre->orig_start = split_pre->start;
-	split_pre->block_start = em->block_start;
+	split_pre->block_start = new_logical;
 	split_pre->block_len = split_pre->len;
 	split_pre->orig_block_len = split_pre->block_len;
 	split_pre->ram_bytes = split_pre->len;
diff --git a/fs/btrfs/extent_map.h b/fs/btrfs/extent_map.h
index 7df39112388d..35d27c756e08 100644
--- a/fs/btrfs/extent_map.h
+++ b/fs/btrfs/extent_map.h
@@ -90,7 +90,8 @@ struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree,
 int add_extent_mapping(struct extent_map_tree *tree,
 		       struct extent_map *em, int modified);
 void remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em);
-int split_extent_map(struct btrfs_inode *inode, u64 start, u64 len, u64 pre);
+int split_extent_map(struct btrfs_inode *inode, u64 start, u64 len, u64 pre,
+		     u64 new_logical);
 
 struct extent_map *alloc_extent_map(void);
 void free_extent_map(struct extent_map *em);
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index ff3110a2b4e6..b8c64882a1e7 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -2736,7 +2736,8 @@ static int btrfs_extract_ordered_extent(struct btrfs_bio *bbio,
 	 */
 	if (!test_bit(BTRFS_ORDERED_NOCOW, &ordered->flags)) {
 		ret = split_extent_map(bbio->inode, bbio->file_offset,
-				       ordered->num_bytes, len);
+				       ordered->num_bytes, len,
+				       ordered->disk_bytenr);
 		if (ret)
 			return ret;
 	}
diff --git a/fs/btrfs/zoned.c b/fs/btrfs/zoned.c
index b4dd018ba332..f1471cb5fe26 100644
--- a/fs/btrfs/zoned.c
+++ b/fs/btrfs/zoned.c
@@ -1689,15 +1689,13 @@ static bool btrfs_zoned_split_ordered(struct btrfs_ordered_extent *ordered,
 
 	if (!test_bit(BTRFS_ORDERED_NOCOW, &ordered->flags) &&
 	    split_extent_map(BTRFS_I(ordered->inode), ordered->file_offset,
-			     ordered->num_bytes, len))
+			     ordered->num_bytes, len, logical))
 		return false;
 
 	new = btrfs_split_ordered_extent(ordered, len);
 	if (IS_ERR(new))
 		return false;
-
-	if (new->disk_bytenr != logical)
-		btrfs_rewrite_logical_zoned(new, logical);
+	new->disk_bytenr = logical;
 	btrfs_finish_one_ordered(new);
 	return true;
 }