IB: Replace ib_umem page_size by page_shift

Size of pages are held by struct ib_umem in page_size field.

It is better to store it as an exponent, because page size by nature
is always power-of-two and used as a factor, divisor or ilog2's argument.

The conversion of page_size to be page_shift allows to have portable
code and avoid following error while compiling on ARM:

  ERROR: "__aeabi_uldivmod" [drivers/infiniband/core/ib_core.ko] undefined!

CC: Selvin Xavier <selvin.xavier@broadcom.com>
CC: Steve Wise <swise@chelsio.com>
CC: Lijun Ou <oulijun@huawei.com>
CC: Shiraz Saleem <shiraz.saleem@intel.com>
CC: Adit Ranadive <aditr@vmware.com>
CC: Dennis Dalessandro <dennis.dalessandro@intel.com>
CC: Ram Amrani <Ram.Amrani@Cavium.com>
Signed-off-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Acked-by: Ram Amrani <Ram.Amrani@cavium.com>
Acked-by: Shiraz Saleem <shiraz.saleem@intel.com>
Acked-by: Selvin Xavier <selvin.xavier@broadcom.com>
Acked-by: Selvin Xavier <selvin.xavier@broadcom.com>
Acked-by: Adit Ranadive <aditr@vmware.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

drivers/infiniband/hw/ocrdma/ocrdma_verbs.c

@@ -914,21 +914,18 @@ static void build_user_pbes(struct ocrdma_dev *dev, struct ocrdma_mr *mr,
 	pbe = (struct ocrdma_pbe *)pbl_tbl->va;
 	pbe_cnt = 0;
 
-	shift = ilog2(umem->page_size);
+	shift = umem->page_shift;
 
 	for_each_sg(umem->sg_head.sgl, sg, umem->nmap, entry) {
 		pages = sg_dma_len(sg) >> shift;
 		for (pg_cnt = 0; pg_cnt < pages; pg_cnt++) {
 			/* store the page address in pbe */
 			pbe->pa_lo =
-			    cpu_to_le32(sg_dma_address
-					(sg) +
-					(umem->page_size * pg_cnt));
+			    cpu_to_le32(sg_dma_address(sg) +
+					(pg_cnt << shift));
 			pbe->pa_hi =
-			    cpu_to_le32(upper_32_bits
-					((sg_dma_address
-					  (sg) +
-					  umem->page_size * pg_cnt)));
+			    cpu_to_le32(upper_32_bits(sg_dma_address(sg) +
+					 (pg_cnt << shift)));
 			pbe_cnt += 1;
 			total_num_pbes += 1;
 			pbe++;
@@ -978,7 +975,7 @@ struct ib_mr *ocrdma_reg_user_mr(struct ib_pd *ibpd, u64 start, u64 len,
 	if (status)
 		goto umem_err;
 
-	mr->hwmr.pbe_size = mr->umem->page_size;
+	mr->hwmr.pbe_size = BIT(mr->umem->page_shift);
 	mr->hwmr.fbo = ib_umem_offset(mr->umem);
 	mr->hwmr.va = usr_addr;
 	mr->hwmr.len = len;