btrfs: sink calc_bio_boundaries into its only caller

Nowadays calc_bio_boundaries() is a relatively simple function that only
guarantees the one bio equals to one ordered extent rule for uncompressed
Zone Append bios.

Sink it into it's only caller alloc_new_bio().
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

fs/btrfs/extent_io.c

@@ -898,10 +898,19 @@ static bool btrfs_bio_is_contig(struct btrfs_bio_ctrl *bio_ctrl,
 		page_offset(page) + pg_offset;
 }
 
-static void calc_bio_boundaries(struct btrfs_bio_ctrl *bio_ctrl,
-				struct btrfs_inode *inode, u64 file_offset)
+static void alloc_new_bio(struct btrfs_inode *inode,
+			  struct btrfs_bio_ctrl *bio_ctrl,
+			  u64 disk_bytenr, u64 file_offset)
 {
-	struct btrfs_ordered_extent *ordered;
+	struct btrfs_fs_info *fs_info = inode->root->fs_info;
+	struct bio *bio;
+
+	bio = btrfs_bio_alloc(BIO_MAX_VECS, bio_ctrl->opf, inode,
+			      bio_ctrl->end_io_func, NULL);
+	bio->bi_iter.bi_sector = disk_bytenr >> SECTOR_SHIFT;
+	btrfs_bio(bio)->file_offset = file_offset;
+	bio_ctrl->bio = bio;
+	bio_ctrl->len_to_oe_boundary = U32_MAX;
 
 	/*
 	 * Limit the extent to the ordered boundary for Zone Append.
@@ -909,34 +918,18 @@ static void calc_bio_boundaries(struct btrfs_bio_ctrl *bio_ctrl,
 	 * them.
 	 */
 	if (bio_ctrl->compress_type == BTRFS_COMPRESS_NONE &&
-	    btrfs_use_zone_append(btrfs_bio(bio_ctrl->bio))) {
+	    btrfs_use_zone_append(btrfs_bio(bio))) {
+		struct btrfs_ordered_extent *ordered;
+
 		ordered = btrfs_lookup_ordered_extent(inode, file_offset);
 		if (ordered) {
 			bio_ctrl->len_to_oe_boundary = min_t(u32, U32_MAX,
 					ordered->file_offset +
 					ordered->disk_num_bytes - file_offset);
 			btrfs_put_ordered_extent(ordered);
-			return;
 		}
 	}
 
-	bio_ctrl->len_to_oe_boundary = U32_MAX;
-}
-
-static void alloc_new_bio(struct btrfs_inode *inode,
-			  struct btrfs_bio_ctrl *bio_ctrl,
-			  u64 disk_bytenr, u64 file_offset)
-{
-	struct btrfs_fs_info *fs_info = inode->root->fs_info;
-	struct bio *bio;
-
-	bio = btrfs_bio_alloc(BIO_MAX_VECS, bio_ctrl->opf, inode,
-			      bio_ctrl->end_io_func, NULL);
-	bio->bi_iter.bi_sector = disk_bytenr >> SECTOR_SHIFT;
-	btrfs_bio(bio)->file_offset = file_offset;
-	bio_ctrl->bio = bio;
-	calc_bio_boundaries(bio_ctrl, inode, file_offset);
-
 	if (bio_ctrl->wbc) {
 		/*
 		 * Pick the last added device to support cgroup writeback.  For