dm writecache: return void from functions

The functions writecache_map_remap_origin and writecache_bio_copy_ssd
only return a single value, thus they can be made to return void.

This helps simplify the following IO accounting changes.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

drivers/md/dm-writecache.c

@@ -1329,7 +1329,7 @@ enum wc_map_op {
 	WC_MAP_ERROR,
 };
 
-static enum wc_map_op writecache_map_remap_origin(struct dm_writecache *wc, struct bio *bio,
+static void writecache_map_remap_origin(struct dm_writecache *wc, struct bio *bio,
 					struct wc_entry *e)
 {
 	if (e) {
@@ -1338,8 +1338,6 @@ static enum wc_map_op writecache_map_remap_origin(struct dm_writecache *wc, stru
 		if (next_boundary < bio->bi_iter.bi_size >> SECTOR_SHIFT)
 			dm_accept_partial_bio(bio, next_boundary);
 	}
-
-	return WC_MAP_REMAP_ORIGIN;
 }
 
 static enum wc_map_op writecache_map_read(struct dm_writecache *wc, struct bio *bio)
@@ -1366,13 +1364,14 @@ static enum wc_map_op writecache_map_read(struct dm_writecache *wc, struct bio *
 			map_op = WC_MAP_REMAP;
 		}
 	} else {
-		map_op = writecache_map_remap_origin(wc, bio, e);
+		writecache_map_remap_origin(wc, bio, e);
+		map_op = WC_MAP_REMAP_ORIGIN;
 	}
 
 	return map_op;
 }
 
-static enum wc_map_op writecache_bio_copy_ssd(struct dm_writecache *wc, struct bio *bio,
+static void writecache_bio_copy_ssd(struct dm_writecache *wc, struct bio *bio,
 				    struct wc_entry *e, bool search_used)
 {
 	unsigned bio_size = wc->block_size;
@@ -1419,8 +1418,6 @@ static enum wc_map_op writecache_bio_copy_ssd(struct dm_writecache *wc, struct b
 	} else {
 		writecache_schedule_autocommit(wc);
 	}
-
-	return WC_MAP_REMAP;
 }
 
 static enum wc_map_op writecache_map_write(struct dm_writecache *wc, struct bio *bio)
@@ -1458,7 +1455,8 @@ static enum wc_map_op writecache_map_write(struct dm_writecache *wc, struct bio
 direct_write:
 				wc->stats.writes_around++;
 				e = writecache_find_entry(wc, bio->bi_iter.bi_sector, WFE_RETURN_FOLLOWING);
-				return writecache_map_remap_origin(wc, bio, e);
+				writecache_map_remap_origin(wc, bio, e);
+				return WC_MAP_REMAP_ORIGIN;
 			}
 			wc->stats.writes_blocked_on_freelist++;
 			writecache_wait_on_freelist(wc);
@@ -1469,10 +1467,12 @@ static enum wc_map_op writecache_map_write(struct dm_writecache *wc, struct bio
 		wc->uncommitted_blocks++;
 		wc->stats.writes_allocate++;
 bio_copy:
-		if (WC_MODE_PMEM(wc))
+		if (WC_MODE_PMEM(wc)) {
 			bio_copy_block(wc, bio, memory_data(wc, e));
-		else
-			return writecache_bio_copy_ssd(wc, bio, e, search_used);
+		} else {
+			writecache_bio_copy_ssd(wc, bio, e, search_used);
+			return WC_MAP_REMAP;
+		}
 	} while (bio->bi_iter.bi_size);
 
 	if (unlikely(bio->bi_opf & REQ_FUA || wc->uncommitted_blocks >= wc->autocommit_blocks))