Merge branch 'for-4.3/sg' of git://git.kernel.dk/linux-block

Pull SG updates from Jens Axboe:
 "This contains a set of scatter-gather related changes/fixes for 4.3:

   - Add support for limited chaining of sg tables even for
     architectures that do not set ARCH_HAS_SG_CHAIN.  From Christoph.

   - Add sg chain support to target_rd.  From Christoph.

   - Fixup open coded sg->page_link in crypto/omap-sham.  From
     Christoph.

   - Fixup open coded crypto ->page_link manipulation.  From Dan.

   - Also from Dan, automated fixup of manual sg_unmark_end()
     manipulations.

   - Also from Dan, automated fixup of open coded sg_phys()
     implementations.

   - From Robert Jarzmik, addition of an sg table splitting helper that
     drivers can use"

* 'for-4.3/sg' of git://git.kernel.dk/linux-block:
  lib: scatterlist: add sg splitting function
  scatterlist: use sg_phys()
  crypto/omap-sham: remove an open coded access to ->page_link
  scatterlist: remove open coded sg_unmark_end instances
  crypto: replace scatterwalk_sg_chain with sg_chain
  target/rd: always chain S/G list
  scatterlist: allow limited chaining without ARCH_HAS_SG_CHAIN

10 files changed, 12 insertions, 57 deletions

diff --git a/drivers/crypto/bfin_crc.c b/drivers/crypto/bfin_crc.c
index d9af940..2f0b333 100644
--- a/drivers/crypto/bfin_crc.c
+++ b/drivers/crypto/bfin_crc.c
@@ -370,8 +370,7 @@ static int bfin_crypto_crc_handle_queue(struct bfin_crypto_crc *crc,
 			sg_init_table(ctx->bufsl, nsg);
 			sg_set_buf(ctx->bufsl, ctx->buflast, ctx->buflast_len);
 			if (nsg > 1)
-				scatterwalk_sg_chain(ctx->bufsl, nsg,
-						req->src);
+				sg_chain(ctx->bufsl, nsg, req->src);
 			ctx->sg = ctx->bufsl;
 		} else
 			ctx->sg = req->src;
diff --git a/drivers/crypto/omap-sham.c b/drivers/crypto/omap-sham.c
index b2024c95..48adb2a 100644
--- a/drivers/crypto/omap-sham.c
+++ b/drivers/crypto/omap-sham.c
@@ -588,7 +588,7 @@ static int omap_sham_xmit_dma(struct omap_sham_dev *dd, dma_addr_t dma_addr,
 		 * the dmaengine may try to DMA the incorrect amount of data.
 		 */
 		sg_init_table(&ctx->sgl, 1);
-		ctx->sgl.page_link = ctx->sg->page_link;
+		sg_assign_page(&ctx->sgl, sg_page(ctx->sg));
 		ctx->sgl.offset = ctx->sg->offset;
 		sg_dma_len(&ctx->sgl) = len32;
 		sg_dma_address(&ctx->sgl) = sg_dma_address(ctx->sg);
diff --git a/drivers/crypto/qce/sha.c b/drivers/crypto/qce/sha.c
index 5c5df1d..be2f504 100644
--- a/drivers/crypto/qce/sha.c
+++ b/drivers/crypto/qce/sha.c
@@ -296,7 +296,7 @@ static int qce_ahash_update(struct ahash_request *req)
 	if (rctx->buflen) {
 		sg_init_table(rctx->sg, 2);
 		sg_set_buf(rctx->sg, rctx->tmpbuf, rctx->buflen);
-		scatterwalk_sg_chain(rctx->sg, 2, req->src);
+		sg_chain(rctx->sg, 2, req->src);
 		req->src = rctx->sg;
 	}
 
diff --git a/drivers/crypto/sahara.c b/drivers/crypto/sahara.c
index 1c19e44..820dc3a 100644
--- a/drivers/crypto/sahara.c
+++ b/drivers/crypto/sahara.c
@@ -999,7 +999,7 @@ static int sahara_sha_prepare_request(struct ahash_request *req)
 		sg_init_table(rctx->in_sg_chain, 2);
 		sg_set_buf(rctx->in_sg_chain, rctx->rembuf, rctx->buf_cnt);
 
-		scatterwalk_sg_chain(rctx->in_sg_chain, 2, req->src);
+		sg_chain(rctx->in_sg_chain, 2, req->src);
 
 		rctx->total = req->nbytes + rctx->buf_cnt;
 		rctx->in_sg = rctx->in_sg_chain;
diff --git a/drivers/crypto/talitos.c b/drivers/crypto/talitos.c
index cd77453..3b20a1b 100644
--- a/drivers/crypto/talitos.c
+++ b/drivers/crypto/talitos.c
@@ -1929,7 +1929,7 @@ static int ahash_process_req(struct ahash_request *areq, unsigned int nbytes)
 		sg_init_table(req_ctx->bufsl, nsg);
 		sg_set_buf(req_ctx->bufsl, req_ctx->buf, req_ctx->nbuf);
 		if (nsg > 1)
-			scatterwalk_sg_chain(req_ctx->bufsl, 2, areq->src);
+			sg_chain(req_ctx->bufsl, 2, areq->src);
 		req_ctx->psrc = req_ctx->bufsl;
 	} else
 		req_ctx->psrc = areq->src;
diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index 697291a..c82ebee 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -2103,7 +2103,7 @@ static int __domain_mapping(struct dmar_domain *domain, unsigned long iov_pfn,
 			sg_res = aligned_nrpages(sg->offset, sg->length);
 			sg->dma_address = ((dma_addr_t)iov_pfn << VTD_PAGE_SHIFT) + sg->offset;
 			sg->dma_length = sg->length;
-			pteval = page_to_phys(sg_page(sg)) | prot;
+			pteval = (sg_phys(sg) & PAGE_MASK) | prot;
 			phys_pfn = pteval >> VTD_PAGE_SHIFT;
 		}
 
@@ -3631,7 +3631,7 @@ static int intel_nontranslate_map_sg(struct device *hddev,
 
 	for_each_sg(sglist, sg, nelems, i) {
 		BUG_ON(!sg_page(sg));
-		sg->dma_address = page_to_phys(sg_page(sg)) + sg->offset;
+		sg->dma_address = sg_phys(sg);
 		sg->dma_length = sg->length;
 	}
 	return nelems;
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index f286090..049df49 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -1408,7 +1408,7 @@ size_t default_iommu_map_sg(struct iommu_domain *domain, unsigned long iova,
 	min_pagesz = 1 << __ffs(domain->ops->pgsize_bitmap);
 
 	for_each_sg(sg, s, nents, i) {
-		phys_addr_t phys = page_to_phys(sg_page(s)) + s->offset;
+		phys_addr_t phys = sg_phys(s);
 
 		/*
 		 * We are mapping on IOMMU page boundaries, so offset within
diff --git a/drivers/mmc/card/queue.c b/drivers/mmc/card/queue.c
index 5daf302..6f4323c 100644
--- a/drivers/mmc/card/queue.c
+++ b/drivers/mmc/card/queue.c
@@ -467,7 +467,7 @@ static unsigned int mmc_queue_packed_map_sg(struct mmc_queue *mq,
 			sg_set_buf(__sg, buf + offset, len);
 			offset += len;
 			remain -= len;
-			(__sg++)->page_link &= ~0x02;
+			sg_unmark_end(__sg++);
 			sg_len++;
 		} while (remain);
 	}
@@ -475,7 +475,7 @@ static unsigned int mmc_queue_packed_map_sg(struct mmc_queue *mq,
 	list_for_each_entry(req, &packed->list, queuelist) {
 		sg_len += blk_rq_map_sg(mq->queue, req, __sg);
 		__sg = sg + (sg_len - 1);
-		(__sg++)->page_link &= ~0x02;
+		sg_unmark_end(__sg++);
 	}
 	sg_mark_end(sg + (sg_len - 1));
 	return sg_len;
diff --git a/drivers/staging/android/ion/ion_chunk_heap.c b/drivers/staging/android/ion/ion_chunk_heap.c
index 0813163..195c41d 100644
--- a/drivers/staging/android/ion/ion_chunk_heap.c
+++ b/drivers/staging/android/ion/ion_chunk_heap.c
@@ -81,7 +81,7 @@ static int ion_chunk_heap_allocate(struct ion_heap *heap,
 err:
 	sg = table->sgl;
 	for (i -= 1; i >= 0; i--) {
-		gen_pool_free(chunk_heap->pool, page_to_phys(sg_page(sg)),
+		gen_pool_free(chunk_heap->pool, sg_phys(sg) & PAGE_MASK,
 			      sg->length);
 		sg = sg_next(sg);
 	}
@@ -109,7 +109,7 @@ static void ion_chunk_heap_free(struct ion_buffer *buffer)
 							DMA_BIDIRECTIONAL);
 
 	for_each_sg(table->sgl, sg, table->nents, i) {
-		gen_pool_free(chunk_heap->pool, page_to_phys(sg_page(sg)),
+		gen_pool_free(chunk_heap->pool, sg_phys(sg) & PAGE_MASK,
 			      sg->length);
 	}
 	chunk_heap->allocated -= allocated_size;
diff --git a/drivers/target/target_core_rd.c b/drivers/target/target_core_rd.c
index 384cf88..47a833f 100644
--- a/drivers/target/target_core_rd.c
+++ b/drivers/target/target_core_rd.c
@@ -138,16 +138,12 @@ static int rd_allocate_sgl_table(struct rd_dev *rd_dev, struct rd_dev_sg_table *
 		sg_per_table = (total_sg_needed > max_sg_per_table) ?
 			max_sg_per_table : total_sg_needed;
 
-#ifdef CONFIG_ARCH_HAS_SG_CHAIN
-
 		/*
 		 * Reserve extra element for chain entry
 		 */
 		if (sg_per_table < total_sg_needed)
 			chain_entry = 1;
 
-#endif /* CONFIG_ARCH_HAS_SG_CHAIN */
-
 		sg = kcalloc(sg_per_table + chain_entry, sizeof(*sg),
 				GFP_KERNEL);
 		if (!sg) {
@@ -158,15 +154,11 @@ static int rd_allocate_sgl_table(struct rd_dev *rd_dev, struct rd_dev_sg_table *
 
 		sg_init_table(sg, sg_per_table + chain_entry);
 
-#ifdef CONFIG_ARCH_HAS_SG_CHAIN
-
 		if (i > 0) {
 			sg_chain(sg_table[i - 1].sg_table,
 				 max_sg_per_table + 1, sg);
 		}
 
-#endif /* CONFIG_ARCH_HAS_SG_CHAIN */
-
 		sg_table[i].sg_table = sg;
 		sg_table[i].rd_sg_count = sg_per_table;
 		sg_table[i].page_start_offset = page_offset;
@@ -430,42 +422,6 @@ static sense_reason_t rd_do_prot_rw(struct se_cmd *cmd, bool is_read)
 	prot_sg = &prot_table->sg_table[prot_page -
 					prot_table->page_start_offset];
 
-#ifndef CONFIG_ARCH_HAS_SG_CHAIN
-
-	prot_npages = DIV_ROUND_UP(prot_offset + sectors * se_dev->prot_length,
-				   PAGE_SIZE);
-
-	/*
-	 * Allocate temporaly contiguous scatterlist entries if prot pages
-	 * straddles multiple scatterlist tables.
-	 */
-	if (prot_table->page_end_offset < prot_page + prot_npages - 1) {
-		int i;
-
-		prot_sg = kcalloc(prot_npages, sizeof(*prot_sg), GFP_KERNEL);
-		if (!prot_sg)
-			return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
-
-		need_to_release = true;
-		sg_init_table(prot_sg, prot_npages);
-
-		for (i = 0; i < prot_npages; i++) {
-			if (prot_page + i > prot_table->page_end_offset) {
-				prot_table = rd_get_prot_table(dev,
-								prot_page + i);
-				if (!prot_table) {
-					kfree(prot_sg);
-					return rc;
-				}
-				sg_unmark_end(&prot_sg[i - 1]);
-			}
-			prot_sg[i] = prot_table->sg_table[prot_page + i -
-						prot_table->page_start_offset];
-		}
-	}
-
-#endif /* !CONFIG_ARCH_HAS_SG_CHAIN */
-
 	if (is_read)
 		rc = sbc_dif_verify(cmd, cmd->t_task_lba, sectors, 0,
 				    prot_sg, prot_offset);