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: NJens Axboe <jens.axboe@oracle.com>

block/ll_rw_blk.c

@@ -1366,9 +1366,7 @@ int blk_rq_map_sg(struct request_queue *q, struct request *rq,
 				sg = sg_next(sg);
 			}
 
-			sg_set_page(sg, bvec->bv_page);
-			sg->length = nbytes;
-			sg->offset = bvec->bv_offset;
+			sg_set_page(sg, bvec->bv_page, nbytes, bvec->bv_offset);
 			nsegs++;
 		}
 		bvprv = bvec;

crypto/hmac.c

@@ -160,8 +160,7 @@ static int hmac_digest(struct hash_desc *pdesc, struct scatterlist *sg,
 
 	sg_set_buf(sg1, ipad, bs);
 
-	sg_set_page(&sg[1], (void *) sg);
-	sg1[1].length = 0;
+	sg_set_page(&sg[1], (void *) sg, 0, 0);
 	sg_set_buf(sg2, opad, bs + ds);
 
 	err = crypto_hash_digest(&desc, sg1, nbytes + bs, digest);

drivers/ata/libata-core.c

@@ -4689,8 +4689,8 @@ static int ata_sg_setup(struct ata_queued_cmd *qc)
 		 * data in this function or read data in ata_sg_clean.
 		 */
 		offset = lsg->offset + lsg->length - qc->pad_len;
-		sg_set_page(psg, nth_page(sg_page(lsg), offset >> PAGE_SHIFT));
-		psg->offset = offset_in_page(offset);
+		sg_set_page(psg, nth_page(sg_page(lsg), offset >> PAGE_SHIFT),
+				qc->pad_len, offset_in_page(offset));
 
 		if (qc->tf.flags & ATA_TFLAG_WRITE) {
 			void *addr = kmap_atomic(sg_page(psg), KM_IRQ0);

drivers/block/cryptoloop.c

@@ -150,13 +150,8 @@ cryptoloop_transfer(struct loop_device *lo, int cmd,
 		u32 iv[4] = { 0, };
 		iv[0] = cpu_to_le32(IV & 0xffffffff);
 
-		sg_set_page(&sg_in, in_page);
-		sg_in.offset = in_offs;
-		sg_in.length = sz;
-
-		sg_set_page(&sg_out, out_page);
-		sg_out.offset = out_offs;
-		sg_out.length = sz;
+		sg_set_page(&sg_in, in_page, sz, in_offs);
+		sg_set_page(&sg_out, out_page, sz, out_offs);
 
 		desc.info = iv;
 		err = encdecfunc(&desc, &sg_out, &sg_in, sz);

drivers/block/ub.c

@@ -1428,9 +1428,8 @@ static void ub_state_sense(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
 	scmd->state = UB_CMDST_INIT;
 	scmd->nsg = 1;
 	sg = &scmd->sgv[0];
-	sg_set_page(sg, virt_to_page(sc->top_sense));
-	sg->offset = (unsigned long)sc->top_sense & (PAGE_SIZE-1);
-	sg->length = UB_SENSE_SIZE;
+	sg_set_page(sg, virt_to_page(sc->top_sense), UB_SENSE_SIZE,
+			(unsigned long)sc->top_sense & (PAGE_SIZE-1));
 	scmd->len = UB_SENSE_SIZE;
 	scmd->lun = cmd->lun;
 	scmd->done = ub_top_sense_done;
@@ -1864,9 +1863,7 @@ static int ub_sync_read_cap(struct ub_dev *sc, struct ub_lun *lun,
 	cmd->state = UB_CMDST_INIT;
 	cmd->nsg = 1;
 	sg = &cmd->sgv[0];
-	sg_set_page(sg, virt_to_page(p));
-	sg->offset = (unsigned long)p & (PAGE_SIZE-1);
-	sg->length = 8;
+	sg_set_page(sg, virt_to_page(p), 8, (unsigned long)p & (PAGE_SIZE-1));
 	cmd->len = 8;
 	cmd->lun = lun;
 	cmd->done = ub_probe_done;

drivers/ieee1394/dma.c

@@ -111,8 +111,8 @@ int dma_region_alloc(struct dma_region *dma, unsigned long n_bytes,
 		unsigned long va =
 		    (unsigned long)dma->kvirt + (i << PAGE_SHIFT);
 
-		sg_set_page(&dma->sglist[i], vmalloc_to_page((void *)va));
-		dma->sglist[i].length = PAGE_SIZE;
+		sg_set_page(&dma->sglist[i], vmalloc_to_page((void *)va),
+				PAGE_SIZE, 0);
 	}
 
 	/* map sglist to the IOMMU */

drivers/infiniband/core/umem.c

@@ -171,9 +171,7 @@ struct ib_umem *ib_umem_get(struct ib_ucontext *context, unsigned long addr,
 				if (vma_list &&
 				    !is_vm_hugetlb_page(vma_list[i + off]))
 					umem->hugetlb = 0;
-				sg_set_page(&chunk->page_list[i], page_list[i + off]);
-				chunk->page_list[i].offset = 0;
-				chunk->page_list[i].length = PAGE_SIZE;
+				sg_set_page(&chunk->page_list[i], page_list[i + off], PAGE_SIZE, 0);
 			}
 
 			chunk->nmap = ib_dma_map_sg(context->device,

drivers/infiniband/hw/mthca/mthca_memfree.c

@@ -113,9 +113,7 @@ static int mthca_alloc_icm_pages(struct scatterlist *mem, int order, gfp_t gfp_m
 	if (!page)
 		return -ENOMEM;
 
-	sg_set_page(mem, page);
-	mem->length = PAGE_SIZE << order;
-	mem->offset = 0;
+	sg_set_page(mem, page, PAGE_SIZE << order, 0);
 	return 0;
 }
 
@@ -481,9 +479,8 @@ int mthca_map_user_db(struct mthca_dev *dev, struct mthca_uar *uar,
 	if (ret < 0)
 		goto out;
 
-	sg_set_page(&db_tab->page[i].mem, pages[0]);
-	db_tab->page[i].mem.length = MTHCA_ICM_PAGE_SIZE;
-	db_tab->page[i].mem.offset = uaddr & ~PAGE_MASK;
+	sg_set_page(&db_tab->page[i].mem, pages[0], MTHCA_ICM_PAGE_SIZE,
+			uaddr & ~PAGE_MASK);
 
 	ret = pci_map_sg(dev->pdev, &db_tab->page[i].mem, 1, PCI_DMA_TODEVICE);
 	if (ret < 0) {

drivers/md/dm-crypt.c

@@ -351,14 +351,10 @@ static int crypt_convert(struct crypt_config *cc,
 		struct scatterlist sg_in, sg_out;
 
 		sg_init_table(&sg_in, 1);
-		sg_set_page(&sg_in, bv_in->bv_page);
-		sg_in.offset = bv_in->bv_offset + ctx->offset_in;
-		sg_in.length = 1 << SECTOR_SHIFT;
+		sg_set_page(&sg_in, bv_in->bv_page, 1 << SECTOR_SHIFT, bv_in->bv_offset + ctx->offset_in);
 
 		sg_init_table(&sg_out, 1);
-		sg_set_page(&sg_out, bv_out->bv_page);
-		sg_out.offset = bv_out->bv_offset + ctx->offset_out;
-		sg_out.length = 1 << SECTOR_SHIFT;
+		sg_set_page(&sg_out, bv_out->bv_page, 1 << SECTOR_SHIFT, bv_out->bv_offset + ctx->offset_out);
 
 		ctx->offset_in += sg_in.length;
 		if (ctx->offset_in >= bv_in->bv_len) {

drivers/media/common/saa7146_core.c

@@ -118,8 +118,7 @@ static struct scatterlist* vmalloc_to_sg(unsigned char *virt, int nr_pages)
 		if (NULL == pg)
 			goto err;
 		BUG_ON(PageHighMem(pg));
-		sg_set_page(&sglist[i], pg);
-		sglist[i].length = PAGE_SIZE;
+		sg_set_page(&sglist[i], pg, PAGE_SIZE, 0);
 	}
 	return sglist;
 

drivers/media/video/ivtv/ivtv-udma.c

@@ -49,8 +49,6 @@ int ivtv_udma_fill_sg_list (struct ivtv_user_dma *dma, struct ivtv_dma_page_info
 		unsigned int len = (i == dma_page->page_count - 1) ?
 			dma_page->tail : PAGE_SIZE - offset;
 
-		dma->SGlist[map_offset].length = len;
-		dma->SGlist[map_offset].offset = offset;
 		if (PageHighMem(dma->map[map_offset])) {
 			void *src;
 
@@ -63,10 +61,10 @@ int ivtv_udma_fill_sg_list (struct ivtv_user_dma *dma, struct ivtv_dma_page_info
 			memcpy(page_address(dma->bouncemap[map_offset]) + offset, src, len);
 			kunmap_atomic(src, KM_BOUNCE_READ);
 			local_irq_restore(flags);
-			sg_set_page(&dma->SGlist[map_offset], dma->bouncemap[map_offset]);
+			sg_set_page(&dma->SGlist[map_offset], dma->bouncemap[map_offset], len, offset);
 		}
 		else {
-			sg_set_page(&dma->SGlist[map_offset], dma->map[map_offset]);
+			sg_set_page(&dma->SGlist[map_offset], dma->map[map_offset], len, offset);
 		}
 		offset = 0;
 		map_offset++;

drivers/media/video/videobuf-dma-sg.c

@@ -67,8 +67,7 @@ videobuf_vmalloc_to_sg(unsigned char *virt, int nr_pages)
 		if (NULL == pg)
 			goto err;
 		BUG_ON(PageHighMem(pg));
-		sg_set_page(&sglist[i], pg);
-		sglist[i].length = PAGE_SIZE;
+		sg_set_page(&sglist[i], pg, PAGE_SIZE, 0);
 	}
 	return sglist;
 
@@ -95,16 +94,13 @@ videobuf_pages_to_sg(struct page **pages, int nr_pages, int offset)
 	if (PageHighMem(pages[0]))
 		/* DMA to highmem pages might not work */
 		goto highmem;
-	sg_set_page(&sglist[0], pages[0]);
-	sglist[0].offset = offset;
-	sglist[0].length = PAGE_SIZE - offset;
+	sg_set_page(&sglist[0], pages[0], PAGE_SIZE - offset, offset);
 	for (i = 1; i < nr_pages; i++) {
 		if (NULL == pages[i])
 			goto nopage;
 		if (PageHighMem(pages[i]))
 			goto highmem;
-		sg_set_page(&sglist[i], pages[i]);
-		sglist[i].length = PAGE_SIZE;
+		sg_set_page(&sglist[i], pages[i], PAGE_SIZE, 0);
 	}
 	return sglist;
 

drivers/net/mlx4/icm.c

@@ -101,9 +101,7 @@ static int mlx4_alloc_icm_pages(struct scatterlist *mem, int order, gfp_t gfp_ma
 	if (!page)
 		return -ENOMEM;
 
-	sg_set_page(mem, page);
-	mem->length = PAGE_SIZE << order;
-	mem->offset = 0;
+	sg_set_page(mem, page, PAGE_SIZE << order, 0);
 	return 0;
 }
 

drivers/s390/scsi/zfcp_aux.c

@@ -562,8 +562,6 @@ zfcp_sg_list_alloc(struct zfcp_sg_list *sg_list, size_t size)
 	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 @@ zfcp_sg_list_alloc(struct zfcp_sg_list *sg_list, size_t size)
 			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 @@ zfcp_gid_pn_buffers_alloc(struct zfcp_gid_pn_data **gid_pn, mempool_t *pool)
         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;

drivers/s390/scsi/zfcp_def.h

@@ -74,8 +74,7 @@ zfcp_sg_to_address(struct scatterlist *list)
 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

drivers/s390/scsi/zfcp_erp.c

@@ -322,9 +322,9 @@ zfcp_erp_adisc(struct zfcp_port *port)
 	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 @@ zfcp_erp_adisc(struct zfcp_port *port)
 	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);

drivers/scsi/ipr.c

@@ -2890,7 +2890,7 @@ static struct ipr_sglist *ipr_alloc_ucode_buffer(int buf_len)
 			return NULL;
 		}
 
-		sg_set_page(&scatterlist[i], page);
+		sg_set_page(&scatterlist[i], page, 0, 0);
 	}
 
 	return sglist;

drivers/scsi/iscsi_tcp.c

@@ -79,9 +79,7 @@ static inline void
 iscsi_buf_init_sg(struct iscsi_buf *ibuf, struct scatterlist *sg)
 {
 	sg_init_table(&ibuf->sg, 1);
-	sg_set_page(&ibuf->sg, sg_page(sg));
-	ibuf->sg.offset = sg->offset;
-	ibuf->sg.length = sg->length;
+	sg_set_page(&ibuf->sg, sg_page(sg), sg->length, sg->offset);
 	/*
 	 * Fastpath: sg element fits into single page
 	 */

drivers/scsi/osst.c

@@ -5256,8 +5256,7 @@ static int enlarge_buffer(struct osst_buffer *STbuffer, int need_dma)
 
 		STbuffer->sg[0].offset = 0;
 		if (page != NULL) {
-		    sg_set_page(&STbuffer->sg[0], page);
-		    STbuffer->sg[0].length = b_size;
+		    sg_set_page(&STbuffer->sg[0], page, b_size, 0);
 		    STbuffer->b_data = page_address(page);
 		    break;
 		}
@@ -5285,8 +5284,7 @@ static int enlarge_buffer(struct osst_buffer *STbuffer, int need_dma)
 			normalize_buffer(STbuffer);
 			return 0;
 		}
-		sg_set_page(&STbuffer->sg[segs], page);
-		STbuffer->sg[segs].length = (OS_FRAME_SIZE - got <= PAGE_SIZE / 2) ? (OS_FRAME_SIZE - got) : b_size;
+		sg_set_page(&STbuffer->sg[segs], page, (OS_FRAME_SIZE - got <= PAGE_SIZE / 2) ? (OS_FRAME_SIZE - got) : b_size, 0);
 		got += STbuffer->sg[segs].length;
 		STbuffer->buffer_size = got;
 		STbuffer->sg_segs = ++segs;

drivers/scsi/sg.c

@@ -1717,16 +1717,12 @@ st_map_user_pages(struct scatterlist *sgl, const unsigned int max_pages,
 		   goto out_unlock; */
         }
 
-	sg_set_page(sgl, pages[0]);
-	sgl[0].offset = uaddr & ~PAGE_MASK;
+	sg_set_page(sgl, pages[0], 0, uaddr & ~PAGE_MASK);
 	if (nr_pages > 1) {
 		sgl[0].length = PAGE_SIZE - sgl[0].offset;
 		count -= sgl[0].length;
-		for (i=1; i < nr_pages ; i++) {
-			sg_set_page(&sgl[i], pages[i]);
-			sgl[i].length = count < PAGE_SIZE ? count : PAGE_SIZE;
-			count -= PAGE_SIZE;
-		}
+		for (i=1; i < nr_pages ; i++)
+			sg_set_page(&sgl[i], pages[i], count < PAGE_SIZE ? count : PAGE_SIZE, 0);
 	}
 	else {
 		sgl[0].length = count;
@@ -1854,8 +1850,7 @@ sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
 				scatter_elem_sz_prev = ret_sz;
 			}
 		}
-		sg_set_page(sg, p);
-		sg->length = (ret_sz > num) ? num : ret_sz;
+		sg_set_page(sg, p, (ret_sz > num) ? num : ret_sz, 0);
 
 		SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k=%d, num=%d, "
 				 "ret_sz=%d\n", k, num, ret_sz));

drivers/scsi/st.c

@@ -3797,13 +3797,11 @@ static void buf_to_sg(struct st_buffer *STbp, unsigned int length)
 	sg = &(STbp->sg[0]);
 	frp = STbp->frp;
 	for (i=count=0; count < length; i++) {
-		sg_set_page(&sg[i], frp[i].page);
 		if (length - count > frp[i].length)
-			sg[i].length = frp[i].length;
+			sg_set_page(&sg[i], frp[i].page, frp[i].length, 0);
 		else
-			sg[i].length = length - count;
+			sg_set_page(&sg[i], frp[i].page, length - count, 0);
 		count += sg[i].length;
-		sg[i].offset = 0;
 	}
 	STbp->sg_segs = i;
 	STbp->frp_sg_current = length;
@@ -4446,15 +4444,13 @@ static int sgl_map_user_pages(struct scatterlist *sgl, const unsigned int max_pa
         }
 
 	/* Populate the scatter/gather list */
-	sg_set_page(&sgl[0], pages[0]);
-	sgl[0].offset = uaddr & ~PAGE_MASK;
+	sg_set_page(&sgl[0], pages[0], 0, uaddr & ~PAGE_MASK);
 	if (nr_pages > 1) {
 		sgl[0].length = PAGE_SIZE - sgl[0].offset;
 		count -= sgl[0].length;
 		for (i=1; i < nr_pages ; i++) {
-			sg_set_page(&sgl[i], pages[i]);;
-			sgl[i].offset = 0;
-			sgl[i].length = count < PAGE_SIZE ? count : PAGE_SIZE;
+			sg_set_page(&sgl[i], pages[i],
+				    count < PAGE_SIZE ? count : PAGE_SIZE, 0);;
 			count -= PAGE_SIZE;
 		}
 	}

fs/ecryptfs/crypto.c

@@ -282,10 +282,8 @@ int virt_to_scatterlist(const void *addr, int size, struct scatterlist *sg,
 	while (size > 0 && i < sg_size) {
 		pg = virt_to_page(addr);
 		offset = offset_in_page(addr);
-		if (sg) {
-			sg_set_page(&sg[i], pg);
-			sg[i].offset = offset;
-		}
+		if (sg)
+			sg_set_page(&sg[i], pg, 0, offset);
 		remainder_of_page = PAGE_CACHE_SIZE - offset;
 		if (size >= remainder_of_page) {
 			if (sg)
@@ -716,12 +714,8 @@ ecryptfs_encrypt_page_offset(struct ecryptfs_crypt_stat *crypt_stat,
 	sg_init_table(&src_sg, 1);
 	sg_init_table(&dst_sg, 1);
 
-	sg_set_page(&src_sg, src_page);
-	src_sg.offset = src_offset;
-	src_sg.length = size;
-	sg_set_page(&dst_sg, dst_page);
-	dst_sg.offset = dst_offset;
-	dst_sg.length = size;
+	sg_set_page(&src_sg, src_page, size, src_offset);
+	sg_set_page(&dst_sg, dst_page, size, dst_offset);
 	return encrypt_scatterlist(crypt_stat, &dst_sg, &src_sg, size, iv);
 }
 
@@ -746,14 +740,11 @@ ecryptfs_decrypt_page_offset(struct ecryptfs_crypt_stat *crypt_stat,
 	struct scatterlist src_sg, dst_sg;
 
 	sg_init_table(&src_sg, 1);
+	sg_set_page(&src_sg, src_page, size, src_offset);
+
 	sg_init_table(&dst_sg, 1);
+	sg_set_page(&dst_sg, dst_page, size, dst_offset);
 
-	sg_set_page(&src_sg, src_page);
-	src_sg.offset = src_offset;
-	src_sg.length = size;
-	sg_set_page(&dst_sg, dst_page);
-	dst_sg.offset = dst_offset;
-	dst_sg.length = size;
 	return decrypt_scatterlist(crypt_stat, &dst_sg, &src_sg, size, iv);
 }
 

include/asm-frv/scatterlist.h

@@ -16,8 +16,7 @@
  *
  * can be rewritten as
  *
- * sg_set_page(virt_to_page(some_ptr));
- * sg->offset = (unsigned long) some_ptr & ~PAGE_MASK;
+ * sg_set_buf(sg, some_ptr, length);
  *
  * and that's it. There's no excuse for not highmem enabling YOUR driver. /jens
  */

include/linux/scatterlist.h

@@ -26,18 +26,16 @@
 #define SG_MAGIC	0x87654321
 
 /**
- * sg_set_page - Set sg entry to point at given page
- * @sg:		 SG entry
- * @page:	 The page
+ * sg_assign_page - Assign a given page to an SG entry
+ * @sg:		    SG entry
+ * @page:	    The page
  *
  * Description:
- *   Use this function to set an sg entry pointing at a page, never assign
- *   the page directly. We encode sg table information in the lower bits
- *   of the page pointer. See sg_page() for looking up the page belonging
- *   to an sg entry.
+ *   Assign page to sg entry. Also see sg_set_page(), the most commonly used
+ *   variant.
  *
  **/
-static inline void sg_set_page(struct scatterlist *sg, struct page *page)
+static inline void sg_assign_page(struct scatterlist *sg, struct page *page)
 {
 	unsigned long page_link = sg->page_link & 0x3;
 
@@ -52,6 +50,28 @@ static inline void sg_set_page(struct scatterlist *sg, struct page *page)
 	sg->page_link = page_link | (unsigned long) page;
 }
 
+/**
+ * sg_set_page - Set sg entry to point at given page
+ * @sg:		 SG entry
+ * @page:	 The page
+ * @len:	 Length of data
+ * @offset:	 Offset into page
+ *
+ * Description:
+ *   Use this function to set an sg entry pointing at a page, never assign
+ *   the page directly. We encode sg table information in the lower bits
+ *   of the page pointer. See sg_page() for looking up the page belonging
+ *   to an sg entry.
+ *
+ **/
+static inline void sg_set_page(struct scatterlist *sg, struct page *page,
+			       unsigned int len, unsigned int offset)
+{
+	sg_assign_page(sg, page);
+	sg->offset = offset;
+	sg->length = len;
+}
+
 #define sg_page(sg)	((struct page *) ((sg)->page_link & ~0x3))
 
 /**
@@ -64,9 +84,7 @@ static inline void sg_set_page(struct scatterlist *sg, struct page *page)
 static inline void sg_set_buf(struct scatterlist *sg, const void *buf,
 			      unsigned int buflen)
 {
-	sg_set_page(sg, virt_to_page(buf));
-	sg->offset = offset_in_page(buf);
-	sg->length = buflen;
+	sg_set_page(sg, virt_to_page(buf), buflen, offset_in_page(buf));
 }
 
 /*

net/core/skbuff.c

@@ -2045,9 +2045,7 @@ skb_to_sgvec(struct sk_buff *skb, struct scatterlist *sg, int offset, int len)
 	if (copy > 0) {
 		if (copy > len)
 			copy = len;
-		sg_set_page(&sg[elt], virt_to_page(skb->data + offset));
-		sg[elt].offset = (unsigned long)(skb->data + offset) % PAGE_SIZE;
-		sg[elt].length = copy;
+		sg_set_buf(sg, skb->data + offset, copy);
 		elt++;
 		if ((len -= copy) == 0)
 			return elt;
@@ -2065,9 +2063,8 @@ skb_to_sgvec(struct sk_buff *skb, struct scatterlist *sg, int offset, int len)
 
 			if (copy > len)
 				copy = len;
-			sg_set_page(&sg[elt], frag->page);
-			sg[elt].offset = frag->page_offset+offset-start;
-			sg[elt].length = copy;
+			sg_set_page(&sg[elt], frag->page, copy,
+					frag->page_offset+offset-start);
 			elt++;
 			if (!(len -= copy))
 				return elt;

net/ieee80211/ieee80211_crypt_tkip.c

@@ -537,13 +537,8 @@ static int michael_mic(struct crypto_hash *tfm_michael, u8 * key, u8 * hdr,
 		return -1;
 	}
 	sg_init_table(sg, 2);
-	sg_set_page(&sg[0], virt_to_page(hdr));
-	sg[0].offset = offset_in_page(hdr);
-	sg[0].length = 16;
-
-	sg_set_page(&sg[1], virt_to_page(data));
-	sg[1].offset = offset_in_page(data);
-	sg[1].length = data_len;
+	sg_set_buf(&sg[0], hdr, 16);
+	sg_set_buf(&sg[1], data, data_len);
 
 	if (crypto_hash_setkey(tfm_michael, key, 8))
 		return -1;

net/sctp/auth.c

@@ -727,9 +727,7 @@ void sctp_auth_calculate_hmac(const struct sctp_association *asoc,
 	/* set up scatter list */
 	end = skb_tail_pointer(skb);
 	sg_init_table(&sg, 1);
-	sg_set_page(&sg, virt_to_page(auth));
-	sg.offset = (unsigned long)(auth) % PAGE_SIZE;
-	sg.length = end - (unsigned char *)auth;
+	sg_set_buf(&sg, auth, end - (unsigned char *)auth);
 
 	desc.tfm = asoc->ep->auth_hmacs[hmac_id];
 	desc.flags = 0;

net/sctp/sm_make_chunk.c

@@ -1514,9 +1514,7 @@ static sctp_cookie_param_t *sctp_pack_cookie(const struct sctp_endpoint *ep,
 
 		/* Sign the message.  */
 		sg_init_table(&sg, 1);
-		sg_set_page(&sg, virt_to_page(&cookie->c));
-		sg.offset = (unsigned long)(&cookie->c) % PAGE_SIZE;
-		sg.length = bodysize;
+		sg_set_buf(&sg, &cookie->c, bodysize);
 		keylen = SCTP_SECRET_SIZE;
 		key = (char *)ep->secret_key[ep->current_key];
 		desc.tfm = sctp_sk(ep->base.sk)->hmac;
@@ -1587,9 +1585,7 @@ struct sctp_association *sctp_unpack_cookie(
 	/* Check the signature.  */
 	keylen = SCTP_SECRET_SIZE;
 	sg_init_table(&sg, 1);
-	sg_set_page(&sg, virt_to_page(bear_cookie));
-	sg.offset = (unsigned long)(bear_cookie) % PAGE_SIZE;
-	sg.length = bodysize;
+	sg_set_buf(&sg, bear_cookie, bodysize);
 	key = (char *)ep->secret_key[ep->current_key];
 	desc.tfm = sctp_sk(ep->base.sk)->hmac;
 	desc.flags = 0;

net/sunrpc/auth_gss/gss_krb5_crypto.c

@@ -199,7 +199,7 @@ encryptor(struct scatterlist *sg, void *data)
 	} else {
 		in_page = sg_page(sg);
 	}
-	sg_set_page(&desc->infrags[desc->fragno], in_page);
+	sg_assign_page(&desc->infrags[desc->fragno], in_page);
 	desc->fragno++;
 	desc->fraglen += sg->length;
 	desc->pos += sg->length;
@@ -215,11 +215,10 @@ encryptor(struct scatterlist *sg, void *data)
 	if (ret)
 		return ret;
 	if (fraglen) {
-		sg_set_page(&desc->outfrags[0], sg_page(sg));
-		desc->outfrags[0].offset = sg->offset + sg->length - fraglen;
-		desc->outfrags[0].length = fraglen;
+		sg_set_page(&desc->outfrags[0], sg_page(sg), fraglen,
+				sg->offset + sg->length - fraglen);
 		desc->infrags[0] = desc->outfrags[0];
-		sg_set_page(&desc->infrags[0], in_page);
+		sg_assign_page(&desc->infrags[0], in_page);
 		desc->fragno = 1;
 		desc->fraglen = fraglen;
 	} else {
@@ -287,9 +286,8 @@ decryptor(struct scatterlist *sg, void *data)
 	if (ret)
 		return ret;
 	if (fraglen) {
-		sg_set_page(&desc->frags[0], sg_page(sg));
-		desc->frags[0].offset = sg->offset + sg->length - fraglen;
-		desc->frags[0].length = fraglen;
+		sg_set_page(&desc->frags[0], sg_page(sg), fraglen,
+				sg->offset + sg->length - fraglen);
 		desc->fragno = 1;
 		desc->fraglen = fraglen;
 	} else {

net/sunrpc/xdr.c

@@ -1059,9 +1059,7 @@ xdr_process_buf(struct xdr_buf *buf, unsigned int offset, unsigned int len,
 		do {
 			if (thislen > page_len)
 				thislen = page_len;
-			sg_set_page(sg, buf->pages[i]);
-			sg->offset = page_offset;
-			sg->length = thislen;
+			sg_set_page(sg, buf->pages[i], thislen, page_offset);
 			ret = actor(sg, data);
 			if (ret)
 				goto out;

net/xfrm/xfrm_algo.c

@@ -553,9 +553,7 @@ int skb_icv_walk(const struct sk_buff *skb, struct hash_desc *desc,
 		if (copy > len)
 			copy = len;
 
-		sg_set_page(&sg, virt_to_page(skb->data + offset));
-		sg.offset = (unsigned long)(skb->data + offset) % PAGE_SIZE;
-		sg.length = copy;
+		sg_set_buf(&sg, skb->data + offset, copy);
 
 		err = icv_update(desc, &sg, copy);
 		if (unlikely(err))
@@ -578,9 +576,8 @@ int skb_icv_walk(const struct sk_buff *skb, struct hash_desc *desc,
 			if (copy > len)
 				copy = len;
 
-			sg_set_page(&sg, frag->page);
-			sg.offset = frag->page_offset + offset-start;
-			sg.length = copy;
+			sg_set_page(&sg, frag->page, copy,
+					frag->page_offset + offset-start);
 
 			err = icv_update(desc, &sg, copy);
 			if (unlikely(err))