btrfs: add optimized version of eb to eb copy
Using copy_extent_buffer is suitable for copying betwenn buffers from an
arbitrary offset and deals with page boundaries. This is not necessary
when doing a full extent_buffer-to-extent_buffer copy. We can utilize
the copy_page helper as well.
Signed-off-by: David Sterba <dsterba@suse.com>
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index be362b7..25286a5 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -260,7 +260,7 @@ int btrfs_copy_root(struct btrfs_trans_handle *trans,
if (IS_ERR(cow))
return PTR_ERR(cow);
- copy_extent_buffer(cow, buf, 0, 0, cow->len);
+ copy_extent_buffer_full(cow, buf);
btrfs_set_header_bytenr(cow, cow->start);
btrfs_set_header_generation(cow, trans->transid);
btrfs_set_header_backref_rev(cow, BTRFS_MIXED_BACKREF_REV);
@@ -1129,7 +1129,7 @@ static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans,
/* cow is set to blocking by btrfs_init_new_buffer */
- copy_extent_buffer(cow, buf, 0, 0, cow->len);
+ copy_extent_buffer_full(cow, buf);
btrfs_set_header_bytenr(cow, cow->start);
btrfs_set_header_generation(cow, trans->transid);
btrfs_set_header_backref_rev(cow, BTRFS_MIXED_BACKREF_REV);