RDMA/ocrdma: Use bitmap_zalloc() when applicable

Use 'bitmap_zalloc()' to simplify code, improve the semantic and avoid
some open-coded arithmetic in allocator arguments.

Also change the corresponding 'kfree()' into 'bitmap_free()' to keep
consistency.

Link: https://lore.kernel.org/r/b157f9e1586fb4d1083cb4058d7ac81b10bb86d7.1637868728.git.christophe.jaillet@wanadoo.frSigned-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

drivers/infiniband/hw/ocrdma/ocrdma_hw.c

@@ -1506,7 +1506,6 @@ int ocrdma_mbx_dealloc_pd(struct ocrdma_dev *dev, struct ocrdma_pd *pd)
 static int ocrdma_mbx_alloc_pd_range(struct ocrdma_dev *dev)
 {
 	int status = -ENOMEM;
-	size_t pd_bitmap_size;
 	struct ocrdma_alloc_pd_range *cmd;
 	struct ocrdma_alloc_pd_range_rsp *rsp;
 
@@ -1528,9 +1527,7 @@ static int ocrdma_mbx_alloc_pd_range(struct ocrdma_dev *dev)
 			dev->pd_mgr->pd_dpp_start = rsp->dpp_page_pdid &
 					OCRDMA_ALLOC_PD_RNG_RSP_START_PDID_MASK;
 			dev->pd_mgr->max_dpp_pd = rsp->pd_count;
-			pd_bitmap_size =
-				BITS_TO_LONGS(rsp->pd_count) * sizeof(long);
-			dev->pd_mgr->pd_dpp_bitmap = kzalloc(pd_bitmap_size,
+			dev->pd_mgr->pd_dpp_bitmap = bitmap_zalloc(rsp->pd_count,
 								   GFP_KERNEL);
 		}
 		kfree(cmd);
@@ -1547,8 +1544,7 @@ static int ocrdma_mbx_alloc_pd_range(struct ocrdma_dev *dev)
 		dev->pd_mgr->pd_norm_start = rsp->dpp_page_pdid &
 					OCRDMA_ALLOC_PD_RNG_RSP_START_PDID_MASK;
 		dev->pd_mgr->max_normal_pd = rsp->pd_count;
-		pd_bitmap_size = BITS_TO_LONGS(rsp->pd_count) * sizeof(long);
-		dev->pd_mgr->pd_norm_bitmap = kzalloc(pd_bitmap_size,
+		dev->pd_mgr->pd_norm_bitmap = bitmap_zalloc(rsp->pd_count,
 							    GFP_KERNEL);
 	}
 	kfree(cmd);
@@ -1611,8 +1607,8 @@ void ocrdma_alloc_pd_pool(struct ocrdma_dev *dev)
 static void ocrdma_free_pd_pool(struct ocrdma_dev *dev)
 {
 	ocrdma_mbx_dealloc_pd_range(dev);
-	kfree(dev->pd_mgr->pd_norm_bitmap);
-	kfree(dev->pd_mgr->pd_dpp_bitmap);
+	bitmap_free(dev->pd_mgr->pd_norm_bitmap);
+	bitmap_free(dev->pd_mgr->pd_dpp_bitmap);
 	kfree(dev->pd_mgr);
 }