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>

19 files changed, 41 insertions, 88 deletions

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 2d147b5..b5f7c59 100644
--- a/drivers/ata/libata-core.c
+++ b/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);
diff --git a/drivers/block/cryptoloop.c b/drivers/block/cryptoloop.c
index 1b58b01..24116787 100644
--- a/drivers/block/cryptoloop.c
+++ b/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);
diff --git a/drivers/block/ub.c b/drivers/block/ub.c
index 14143f2..5e740e1 100644
--- a/drivers/block/ub.c
+++ b/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;
diff --git a/drivers/ieee1394/dma.c b/drivers/ieee1394/dma.c
index 3051e31..f5f4983 100644
--- a/drivers/ieee1394/dma.c
+++ b/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 */
diff --git a/drivers/infiniband/core/umem.c b/drivers/infiniband/core/umem.c
index 14159ff..4e3128f 100644
--- a/drivers/infiniband/core/umem.c
+++ b/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,
diff --git a/drivers/infiniband/hw/mthca/mthca_memfree.c b/drivers/infiniband/hw/mthca/mthca_memfree.c
index 007b381..1f4d27d 100644
--- a/drivers/infiniband/hw/mthca/mthca_memfree.c
+++ b/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) {
diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index ac54f69..1c159ac 100644
--- a/drivers/md/dm-crypt.c
+++ b/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) {
diff --git a/drivers/media/common/saa7146_core.c b/drivers/media/common/saa7146_core.c
index 2b1f8b4..cb034ea 100644
--- a/drivers/media/common/saa7146_core.c
+++ b/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;
 
diff --git a/drivers/media/video/ivtv/ivtv-udma.c b/drivers/media/video/ivtv/ivtv-udma.c
index 912b424..460db03 100644
--- a/drivers/media/video/ivtv/ivtv-udma.c
+++ b/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++;
diff --git a/drivers/media/video/videobuf-dma-sg.c b/drivers/media/video/videobuf-dma-sg.c
index 9ab94a7..44ee408 100644
--- a/drivers/media/video/videobuf-dma-sg.c
+++ b/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;
 
diff --git a/drivers/net/mlx4/icm.c b/drivers/net/mlx4/icm.c
index 887633b..2a5bef6 100644
--- a/drivers/net/mlx4/icm.c
+++ b/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;
 }
 
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 @@ 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;
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 @@ 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
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 @@ 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);
diff --git a/drivers/scsi/ipr.c b/drivers/scsi/ipr.c
index 439b97a..0841df0 100644
--- a/drivers/scsi/ipr.c
+++ b/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;
diff --git a/drivers/scsi/iscsi_tcp.c b/drivers/scsi/iscsi_tcp.c
index 6ce4109..097a136 100644
--- a/drivers/scsi/iscsi_tcp.c
+++ b/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
 	 */
diff --git a/drivers/scsi/osst.c b/drivers/scsi/osst.c
index 1c5c4b6..4652ad2 100644
--- a/drivers/scsi/osst.c
+++ b/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;
diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c
index cc19710..b5fa4f0 100644
--- a/drivers/scsi/sg.c
+++ b/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));
diff --git a/drivers/scsi/st.c b/drivers/scsi/st.c
index ce69b9e..98dfd6e 100644
--- a/drivers/scsi/st.c
+++ b/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;
 		}
 	}