null_blk: simplify copy_from_nullb

It always returns success, so the code that saves the errors status, but
proceeds without checking it looks a bit odd. Clean this up.

Signed-off-by: Keith Busch <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>
Reviewed-by: Johannes Thumshirn <[email protected]>
Reviewed-by: Damien Le Moal <[email protected]>
Reviewed-by: Chaitanya Kulkarni <[email protected]>
Tested-by: Hans Holmberg <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>

Author: keithbusch

drivers/block/null_blk/main.c

@@ -1161,7 +1161,7 @@ static int copy_to_nullb(struct nullb *nullb, struct page *source,
 	return 0;
 }
 
-static int copy_from_nullb(struct nullb *nullb, struct page *dest,
+static void copy_from_nullb(struct nullb *nullb, struct page *dest,
 	unsigned int off, sector_t sector, size_t n)
 {
 	size_t temp, count = 0;
@@ -1184,7 +1184,6 @@ static int copy_from_nullb(struct nullb *nullb, struct page *dest,
 		count += temp;
 		sector += temp >> SECTOR_SHIFT;
 	}
-	return 0;
 }
 
 static void nullb_fill_pattern(struct nullb *nullb, struct page *page,
@@ -1248,8 +1247,8 @@ static int null_transfer(struct nullb *nullb, struct page *page,
 				sector, len);
 
 		if (valid_len) {
-			err = copy_from_nullb(nullb, page, off,
-				sector, valid_len);
+			copy_from_nullb(nullb, page, off, sector,
+					valid_len);
 			off += valid_len;
 			len -= valid_len;
 		}