rbd: use memzero_bvec

Use memzero_bvec instead of reimplementing it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Link: https://lore.kernel.org/r/20210727055646.118787-7-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

drivers/block/rbd.c

@@ -1219,24 +1219,13 @@ static void rbd_dev_mapping_clear(struct rbd_device *rbd_dev)
 	rbd_dev->mapping.size = 0;
 }
 
-static void zero_bvec(struct bio_vec *bv)
-{
-	void *buf;
-	unsigned long flags;
-
-	buf = bvec_kmap_irq(bv, &flags);
-	memset(buf, 0, bv->bv_len);
-	flush_dcache_page(bv->bv_page);
-	bvec_kunmap_irq(buf, &flags);
-}
-
 static void zero_bios(struct ceph_bio_iter *bio_pos, u32 off, u32 bytes)
 {
 	struct ceph_bio_iter it = *bio_pos;
 
 	ceph_bio_iter_advance(&it, off);
 	ceph_bio_iter_advance_step(&it, bytes, ({
-		zero_bvec(&bv);
+		memzero_bvec(&bv);
 	}));
 }
 
@@ -1246,7 +1235,7 @@ static void zero_bvecs(struct ceph_bvec_iter *bvec_pos, u32 off, u32 bytes)
 
 	ceph_bvec_iter_advance(&it, off);
 	ceph_bvec_iter_advance_step(&it, bytes, ({
-		zero_bvec(&bv);
+		memzero_bvec(&bv);
 	}));
 }