SG: Change sg_set_page() to take length and offset argument

Most drivers need to set length and offset as well, so may as well fold
those three lines into one.

Add sg_assign_page() for those two locations that only needed to set
the page, where the offset/length is set outside of the function context.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/drivers/s390/scsi/zfcp_aux.c b/drivers/s390/scsi/zfcp_aux.c
index d9e7be9..0011849 100644
--- a/drivers/s390/scsi/zfcp_aux.c
+++ b/drivers/s390/scsi/zfcp_aux.c
@@ -562,8 +562,6 @@
 	sg_init_table(sg_list->sg, sg_list->count);
 
 	for (i = 0, sg = sg_list->sg; i < sg_list->count; i++, sg++) {
-		sg->length = min(size, PAGE_SIZE);
-		sg->offset = 0;
 		address = (void *) get_zeroed_page(GFP_KERNEL);
 		if (address == NULL) {
 			sg_list->count = i;
@@ -571,7 +569,7 @@
 			retval = -ENOMEM;
 			goto out;
 		}
-		zfcp_address_to_sg(address, sg);
+		zfcp_address_to_sg(address, sg, min(size, PAGE_SIZE));
 		size -= sg->length;
 	}
 
@@ -1523,10 +1521,8 @@
         data->ct.req = &data->req;
         data->ct.resp = &data->resp;
 	data->ct.req_count = data->ct.resp_count = 1;
-	zfcp_address_to_sg(&data->ct_iu_req, &data->req);
-        zfcp_address_to_sg(&data->ct_iu_resp, &data->resp);
-        data->req.length = sizeof(struct ct_iu_gid_pn_req);
-        data->resp.length = sizeof(struct ct_iu_gid_pn_resp);
+	zfcp_address_to_sg(&data->ct_iu_req, &data->req, sizeof(struct ct_iu_gid_pn_req));
+        zfcp_address_to_sg(&data->ct_iu_resp, &data->resp, sizeof(struct ct_iu_gid_pn_resp));
 
 	*gid_pn = data;
 	return 0;
diff --git a/drivers/s390/scsi/zfcp_def.h b/drivers/s390/scsi/zfcp_def.h
index 326e7ee..0754542 100644
--- a/drivers/s390/scsi/zfcp_def.h
+++ b/drivers/s390/scsi/zfcp_def.h
@@ -74,8 +74,7 @@
 static inline void
 zfcp_address_to_sg(void *address, struct scatterlist *list)
 {
-	sg_set_page(list, virt_to_page(address));
-	list->offset = ((unsigned long) address) & (PAGE_SIZE - 1);
+	sg_set_buf(list, address, 0);
 }
 
 #define REQUEST_LIST_SIZE 128
diff --git a/drivers/s390/scsi/zfcp_erp.c b/drivers/s390/scsi/zfcp_erp.c
index 9438d0b..5552b75 100644
--- a/drivers/s390/scsi/zfcp_erp.c
+++ b/drivers/s390/scsi/zfcp_erp.c
@@ -322,9 +322,9 @@
 	if (address == NULL)
 		goto nomem;
 
-	zfcp_address_to_sg(address, send_els->req);
+	zfcp_address_to_sg(address, send_els->req, sizeof(struct zfcp_ls_adisc));
 	address += PAGE_SIZE >> 1;
-	zfcp_address_to_sg(address, send_els->resp);
+	zfcp_address_to_sg(address, send_els->resp, sizeof(struct zfcp_ls_adisc_acc));
 	send_els->req_count = send_els->resp_count = 1;
 
 	send_els->adapter = adapter;
@@ -336,9 +336,6 @@
 	adisc = zfcp_sg_to_address(send_els->req);
 	send_els->ls_code = adisc->code = ZFCP_LS_ADISC;
 
-	send_els->req->length = sizeof(struct zfcp_ls_adisc);
-	send_els->resp->length = sizeof(struct zfcp_ls_adisc_acc);
-
 	/* acc. to FC-FS, hard_nport_id in ADISC should not be set for ports
 	   without FC-AL-2 capability, so we don't set it */
 	adisc->wwpn = fc_host_port_name(adapter->scsi_host);