crypto: caam - dma_map_sg can handle chained SG

The caam driver use two dma_map_sg path according to SG are chained
or not.
Since dma_map_sg can handle both case, clean the code with all
references to sg chained.

Thus removing dma_map_sg_chained, dma_unmap_sg_chained
and __sg_count functions.

Signed-off-by: LABBE Corentin <clabbe.montjoie@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

3 files changed, 53 insertions, 168 deletions

diff --git a/drivers/crypto/caam/caamalg.c b/drivers/crypto/caam/caamalg.c
index ba79d638f782..ad0d1ec51dd5 100644
--- a/drivers/crypto/caam/caamalg.c
+++ b/drivers/crypto/caam/caamalg.c
@@ -1708,11 +1708,8 @@ static int ablkcipher_setkey(struct crypto_ablkcipher *ablkcipher,
 /*
  * aead_edesc - s/w-extended aead descriptor
  * @assoc_nents: number of segments in associated data (SPI+Seq) scatterlist
- * @assoc_chained: if source is chained
  * @src_nents: number of segments in input scatterlist
- * @src_chained: if source is chained
  * @dst_nents: number of segments in output scatterlist
- * @dst_chained: if destination is chained
  * @iv_dma: dma address of iv for checking continuity and link table
  * @desc: h/w descriptor (variable length; must not exceed MAX_CAAM_DESCSIZE)
  * @sec4_sg_bytes: length of dma mapped sec4_sg space
@@ -1721,11 +1718,8 @@ static int ablkcipher_setkey(struct crypto_ablkcipher *ablkcipher,
  */
 struct aead_edesc {
         int assoc_nents;
-        bool assoc_chained;
         int src_nents;
-        bool src_chained;
         int dst_nents;
-        bool dst_chained;
         dma_addr_t iv_dma;
         int sec4_sg_bytes;
         dma_addr_t sec4_sg_dma;
@@ -1736,9 +1730,7 @@ struct aead_edesc {
 /*
  * ablkcipher_edesc - s/w-extended ablkcipher descriptor
  * @src_nents: number of segments in input scatterlist
- * @src_chained: if source is chained
  * @dst_nents: number of segments in output scatterlist
- * @dst_chained: if destination is chained
  * @iv_dma: dma address of iv for checking continuity and link table
  * @desc: h/w descriptor (variable length; must not exceed MAX_CAAM_DESCSIZE)
  * @sec4_sg_bytes: length of dma mapped sec4_sg space
@@ -1747,9 +1739,7 @@ struct aead_edesc {
  */
 struct ablkcipher_edesc {
         int src_nents;
-        bool src_chained;
         int dst_nents;
-        bool dst_chained;
         dma_addr_t iv_dma;
         int sec4_sg_bytes;
         dma_addr_t sec4_sg_dma;
@@ -1759,18 +1749,15 @@ struct ablkcipher_edesc {
 
 static void caam_unmap(struct device *dev, struct scatterlist *src,
                        struct scatterlist *dst, int src_nents,
-                       bool src_chained, int dst_nents, bool dst_chained,
+                       int dst_nents,
                        dma_addr_t iv_dma, int ivsize, dma_addr_t sec4_sg_dma,
                        int sec4_sg_bytes)
 {
         if (dst != src) {
-                dma_unmap_sg_chained(dev, src, src_nents ? : 1, DMA_TO_DEVICE,
-                                     src_chained);
-                dma_unmap_sg_chained(dev, dst, dst_nents ? : 1, DMA_FROM_DEVICE,
-                                     dst_chained);
+                dma_unmap_sg(dev, src, src_nents ? : 1, DMA_TO_DEVICE);
+                dma_unmap_sg(dev, dst, dst_nents ? : 1, DMA_FROM_DEVICE);
         } else {
-                dma_unmap_sg_chained(dev, src, src_nents ? : 1,
-                                     DMA_BIDIRECTIONAL, src_chained);
+                dma_unmap_sg(dev, src, src_nents ? : 1, DMA_BIDIRECTIONAL);
         }
 
         if (iv_dma)
@@ -1785,8 +1772,7 @@ static void aead_unmap(struct device *dev,
                        struct aead_request *req)
 {
         caam_unmap(dev, req->src, req->dst,
-                   edesc->src_nents, edesc->src_chained, edesc->dst_nents,
-                   edesc->dst_chained, 0, 0,
+                   edesc->src_nents, edesc->dst_nents, 0, 0,
                    edesc->sec4_sg_dma, edesc->sec4_sg_bytes);
 }
 
@@ -1798,8 +1784,8 @@ static void ablkcipher_unmap(struct device *dev,
         int ivsize = crypto_ablkcipher_ivsize(ablkcipher);
 
         caam_unmap(dev, req->src, req->dst,
-                   edesc->src_nents, edesc->src_chained, edesc->dst_nents,
-                   edesc->dst_chained, edesc->iv_dma, ivsize,
+                   edesc->src_nents, edesc->dst_nents,
+                   edesc->iv_dma, ivsize,
                    edesc->sec4_sg_dma, edesc->sec4_sg_bytes);
 }
 
@@ -2169,22 +2155,18 @@ static struct aead_edesc *aead_edesc_alloc(struct aead_request *req,
         struct aead_edesc *edesc;
         int sgc;
         bool all_contig = true;
-        bool src_chained = false, dst_chained = false;
         int sec4_sg_index, sec4_sg_len = 0, sec4_sg_bytes;
         unsigned int authsize = ctx->authsize;
 
         if (unlikely(req->dst != req->src)) {
-                src_nents = sg_count(req->src, req->assoclen + req->cryptlen,
-                                     &src_chained);
+                src_nents = sg_count(req->src, req->assoclen + req->cryptlen);
                 dst_nents = sg_count(req->dst,
                                      req->assoclen + req->cryptlen +
-                                        (encrypt ? authsize : (-authsize)),
-                                     &dst_chained);
+                                        (encrypt ? authsize : (-authsize)));
         } else {
                 src_nents = sg_count(req->src,
                                      req->assoclen + req->cryptlen +
-                                        (encrypt ? authsize : 0),
-                                     &src_chained);
+                                        (encrypt ? authsize : 0));
         }
 
         /* Check if data are contiguous. */
@@ -2207,37 +2189,35 @@ static struct aead_edesc *aead_edesc_alloc(struct aead_request *req,
         }
 
         if (likely(req->src == req->dst)) {
-                sgc = dma_map_sg_chained(jrdev, req->src, src_nents ? : 1,
-                                         DMA_BIDIRECTIONAL, src_chained);
+                sgc = dma_map_sg(jrdev, req->src, src_nents ? : 1,
+                                 DMA_BIDIRECTIONAL);
                 if (unlikely(!sgc)) {
                         dev_err(jrdev, "unable to map source\n");
                         kfree(edesc);
                         return ERR_PTR(-ENOMEM);
                 }
         } else {
-                sgc = dma_map_sg_chained(jrdev, req->src, src_nents ? : 1,
-                                         DMA_TO_DEVICE, src_chained);
+                sgc = dma_map_sg(jrdev, req->src, src_nents ? : 1,
+                                 DMA_TO_DEVICE);
                 if (unlikely(!sgc)) {
                         dev_err(jrdev, "unable to map source\n");
                         kfree(edesc);
                         return ERR_PTR(-ENOMEM);
                 }
 
-                sgc = dma_map_sg_chained(jrdev, req->dst, dst_nents ? : 1,
-                                         DMA_FROM_DEVICE, dst_chained);
+                sgc = dma_map_sg(jrdev, req->dst, dst_nents ? : 1,
+                                 DMA_FROM_DEVICE);
                 if (unlikely(!sgc)) {
                         dev_err(jrdev, "unable to map destination\n");
-                        dma_unmap_sg_chained(jrdev, req->src, src_nents ? : 1,
-                                             DMA_TO_DEVICE, src_chained);
+                        dma_unmap_sg(jrdev, req->src, src_nents ? : 1,
+                                     DMA_TO_DEVICE);
                         kfree(edesc);
                         return ERR_PTR(-ENOMEM);
                 }
         }
 
         edesc->src_nents = src_nents;
-        edesc->src_chained = src_chained;
         edesc->dst_nents = dst_nents;
-        edesc->dst_chained = dst_chained;
         edesc->sec4_sg = (void *)edesc + sizeof(struct aead_edesc) +
                          desc_bytes;
         *all_contig_ptr = all_contig;
@@ -2467,22 +2447,21 @@ static struct ablkcipher_edesc *ablkcipher_edesc_alloc(struct ablkcipher_request
         bool iv_contig = false;
         int sgc;
         int ivsize = crypto_ablkcipher_ivsize(ablkcipher);
-        bool src_chained = false, dst_chained = false;
         int sec4_sg_index;
 
-        src_nents = sg_count(req->src, req->nbytes, &src_chained);
+        src_nents = sg_count(req->src, req->nbytes);
 
         if (req->dst != req->src)
-                dst_nents = sg_count(req->dst, req->nbytes, &dst_chained);
+                dst_nents = sg_count(req->dst, req->nbytes);
 
         if (likely(req->src == req->dst)) {
-                sgc = dma_map_sg_chained(jrdev, req->src, src_nents ? : 1,
-                                         DMA_BIDIRECTIONAL, src_chained);
+                sgc = dma_map_sg(jrdev, req->src, src_nents ? : 1,
+                                 DMA_BIDIRECTIONAL);
         } else {
-                sgc = dma_map_sg_chained(jrdev, req->src, src_nents ? : 1,
-                                         DMA_TO_DEVICE, src_chained);
-                sgc = dma_map_sg_chained(jrdev, req->dst, dst_nents ? : 1,
-                                         DMA_FROM_DEVICE, dst_chained);
+                sgc = dma_map_sg(jrdev, req->src, src_nents ? : 1,
+                                 DMA_TO_DEVICE);
+                sgc = dma_map_sg(jrdev, req->dst, dst_nents ? : 1,
+                                 DMA_FROM_DEVICE);
         }
 
         iv_dma = dma_map_single(jrdev, req->info, ivsize, DMA_TO_DEVICE);
@@ -2511,9 +2490,7 @@ static struct ablkcipher_edesc *ablkcipher_edesc_alloc(struct ablkcipher_request
         }
 
         edesc->src_nents = src_nents;
-        edesc->src_chained = src_chained;
         edesc->dst_nents = dst_nents;
-        edesc->dst_chained = dst_chained;
         edesc->sec4_sg_bytes = sec4_sg_bytes;
         edesc->sec4_sg = (void *)edesc + sizeof(struct ablkcipher_edesc) +
                          desc_bytes;
@@ -2646,22 +2623,21 @@ static struct ablkcipher_edesc *ablkcipher_giv_edesc_alloc(
         bool iv_contig = false;
         int sgc;
         int ivsize = crypto_ablkcipher_ivsize(ablkcipher);
-        bool src_chained = false, dst_chained = false;
         int sec4_sg_index;
 
-        src_nents = sg_count(req->src, req->nbytes, &src_chained);
+        src_nents = sg_count(req->src, req->nbytes);
 
         if (unlikely(req->dst != req->src))
-                dst_nents = sg_count(req->dst, req->nbytes, &dst_chained);
+                dst_nents = sg_count(req->dst, req->nbytes);
 
         if (likely(req->src == req->dst)) {
-                sgc = dma_map_sg_chained(jrdev, req->src, src_nents ? : 1,
-                                         DMA_BIDIRECTIONAL, src_chained);
+                sgc = dma_map_sg(jrdev, req->src, src_nents ? : 1,
+                                 DMA_BIDIRECTIONAL);
         } else {
-                sgc = dma_map_sg_chained(jrdev, req->src, src_nents ? : 1,
-                                         DMA_TO_DEVICE, src_chained);
-                sgc = dma_map_sg_chained(jrdev, req->dst, dst_nents ? : 1,
-                                         DMA_FROM_DEVICE, dst_chained);
+                sgc = dma_map_sg(jrdev, req->src, src_nents ? : 1,
+                                 DMA_TO_DEVICE);
+                sgc = dma_map_sg(jrdev, req->dst, dst_nents ? : 1,
+                                 DMA_FROM_DEVICE);
         }
 
         /*
@@ -2690,9 +2666,7 @@ static struct ablkcipher_edesc *ablkcipher_giv_edesc_alloc(
         }
 
         edesc->src_nents = src_nents;
-        edesc->src_chained = src_chained;
         edesc->dst_nents = dst_nents;
-        edesc->dst_chained = dst_chained;
         edesc->sec4_sg_bytes = sec4_sg_bytes;
         edesc->sec4_sg = (void *)edesc + sizeof(struct ablkcipher_edesc) +
                          desc_bytes;
diff --git a/drivers/crypto/caam/caamhash.c b/drivers/crypto/caam/caamhash.c
index 94433b9fc200..9609f6634329 100644
--- a/drivers/crypto/caam/caamhash.c
+++ b/drivers/crypto/caam/caamhash.c
@@ -181,10 +181,9 @@ static inline dma_addr_t buf_map_to_sec4_sg(struct device *jrdev,
 /* Map req->src and put it in link table */
 static inline void src_map_to_sec4_sg(struct device *jrdev,
                                       struct scatterlist *src, int src_nents,
-                                      struct sec4_sg_entry *sec4_sg,
-                                      bool chained)
+                                      struct sec4_sg_entry *sec4_sg)
 {
-        dma_map_sg_chained(jrdev, src, src_nents, DMA_TO_DEVICE, chained);
+        dma_map_sg(jrdev, src, src_nents, DMA_TO_DEVICE);
         sg_to_sec4_sg_last(src, src_nents, sec4_sg, 0);
 }
 
@@ -585,7 +584,6 @@ badkey:
  * ahash_edesc - s/w-extended ahash descriptor
  * @dst_dma: physical mapped address of req->result
  * @sec4_sg_dma: physical mapped address of h/w link table
- * @chained: if source is chained
  * @src_nents: number of segments in input scatterlist
  * @sec4_sg_bytes: length of dma mapped sec4_sg space
  * @sec4_sg: pointer to h/w link table
@@ -594,7 +592,6 @@ badkey:
 struct ahash_edesc {
         dma_addr_t dst_dma;
         dma_addr_t sec4_sg_dma;
-        bool chained;
         int src_nents;
         int sec4_sg_bytes;
         struct sec4_sg_entry *sec4_sg;
@@ -606,8 +603,7 @@ static inline void ahash_unmap(struct device *dev,
                         struct ahash_request *req, int dst_len)
 {
         if (edesc->src_nents)
-                dma_unmap_sg_chained(dev, req->src, edesc->src_nents,
-                                     DMA_TO_DEVICE, edesc->chained);
+                dma_unmap_sg(dev, req->src, edesc->src_nents, DMA_TO_DEVICE);
         if (edesc->dst_dma)
                 dma_unmap_single(dev, edesc->dst_dma, dst_len, DMA_FROM_DEVICE);
 
@@ -788,7 +784,6 @@ static int ahash_update_ctx(struct ahash_request *req)
         dma_addr_t ptr = ctx->sh_desc_update_dma;
         int src_nents, sec4_sg_bytes, sec4_sg_src_index;
         struct ahash_edesc *edesc;
-        bool chained = false;
         int ret = 0;
         int sh_len;
 
@@ -797,8 +792,8 @@ static int ahash_update_ctx(struct ahash_request *req)
         to_hash = in_len - *next_buflen;
 
         if (to_hash) {
-                src_nents = __sg_count(req->src, req->nbytes - (*next_buflen),
-                                       &chained);
+                src_nents = sg_nents_for_len(req->src,
+                                             req->nbytes - (*next_buflen));
                 sec4_sg_src_index = 1 + (*buflen ? 1 : 0);
                 sec4_sg_bytes = (sec4_sg_src_index + src_nents) *
                                  sizeof(struct sec4_sg_entry);
@@ -816,7 +811,6 @@ static int ahash_update_ctx(struct ahash_request *req)
                 }
 
                 edesc->src_nents = src_nents;
-                edesc->chained = chained;
                 edesc->sec4_sg_bytes = sec4_sg_bytes;
                 edesc->sec4_sg = (void *)edesc + sizeof(struct ahash_edesc) +
                                  DESC_JOB_IO_LEN;
@@ -833,8 +827,7 @@ static int ahash_update_ctx(struct ahash_request *req)
 
                 if (src_nents) {
                         src_map_to_sec4_sg(jrdev, req->src, src_nents,
-                                           edesc->sec4_sg + sec4_sg_src_index,
-                                           chained);
+                                           edesc->sec4_sg + sec4_sg_src_index);
                         if (*next_buflen)
                                 scatterwalk_map_and_copy(next_buf, req->src,
                                                          to_hash - *buflen,
@@ -996,11 +989,10 @@ static int ahash_finup_ctx(struct ahash_request *req)
         int src_nents;
         int digestsize = crypto_ahash_digestsize(ahash);
         struct ahash_edesc *edesc;
-        bool chained = false;
         int ret = 0;
         int sh_len;
 
-        src_nents = __sg_count(req->src, req->nbytes, &chained);
+        src_nents = sg_nents_for_len(req->src, req->nbytes);
         sec4_sg_src_index = 1 + (buflen ? 1 : 0);
         sec4_sg_bytes = (sec4_sg_src_index + src_nents) *
                          sizeof(struct sec4_sg_entry);
@@ -1018,7 +1010,6 @@ static int ahash_finup_ctx(struct ahash_request *req)
         init_job_desc_shared(desc, ptr, sh_len, HDR_SHARE_DEFER | HDR_REVERSE);
 
         edesc->src_nents = src_nents;
-        edesc->chained = chained;
         edesc->sec4_sg_bytes = sec4_sg_bytes;
         edesc->sec4_sg = (void *)edesc + sizeof(struct ahash_edesc) +
                          DESC_JOB_IO_LEN;
@@ -1033,7 +1024,7 @@ static int ahash_finup_ctx(struct ahash_request *req)
                                                 last_buflen);
 
         src_map_to_sec4_sg(jrdev, req->src, src_nents, edesc->sec4_sg +
-                           sec4_sg_src_index, chained);
+                           sec4_sg_src_index);
 
         edesc->sec4_sg_dma = dma_map_single(jrdev, edesc->sec4_sg,
                                             sec4_sg_bytes, DMA_TO_DEVICE);
@@ -1081,14 +1072,12 @@ static int ahash_digest(struct ahash_request *req)
         int src_nents, sec4_sg_bytes;
         dma_addr_t src_dma;
         struct ahash_edesc *edesc;
-        bool chained = false;
         int ret = 0;
         u32 options;
         int sh_len;
 
-        src_nents = sg_count(req->src, req->nbytes, &chained);
-        dma_map_sg_chained(jrdev, req->src, src_nents ? : 1, DMA_TO_DEVICE,
-                           chained);
+        src_nents = sg_count(req->src, req->nbytes);
+        dma_map_sg(jrdev, req->src, src_nents ? : 1, DMA_TO_DEVICE);
         sec4_sg_bytes = src_nents * sizeof(struct sec4_sg_entry);
 
         /* allocate space for base edesc and hw desc commands, link tables */
@@ -1102,7 +1091,6 @@ static int ahash_digest(struct ahash_request *req)
                           DESC_JOB_IO_LEN;
         edesc->sec4_sg_bytes = sec4_sg_bytes;
         edesc->src_nents = src_nents;
-        edesc->chained = chained;
 
         sh_len = desc_len(sh_desc);
         desc = edesc->hw_desc;
@@ -1228,7 +1216,6 @@ static int ahash_update_no_ctx(struct ahash_request *req)
         struct ahash_edesc *edesc;
         u32 *desc, *sh_desc = ctx->sh_desc_update_first;
         dma_addr_t ptr = ctx->sh_desc_update_first_dma;
-        bool chained = false;
         int ret = 0;
         int sh_len;
 
@@ -1236,8 +1223,8 @@ static int ahash_update_no_ctx(struct ahash_request *req)
         to_hash = in_len - *next_buflen;
 
         if (to_hash) {
-                src_nents = __sg_count(req->src, req->nbytes - (*next_buflen),
-                                       &chained);
+                src_nents = sg_nents_for_len(req->src,
+                                             req->nbytes - (*next_buflen));
                 sec4_sg_bytes = (1 + src_nents) *
                                 sizeof(struct sec4_sg_entry);
 
@@ -1254,7 +1241,6 @@ static int ahash_update_no_ctx(struct ahash_request *req)
                 }
 
                 edesc->src_nents = src_nents;
-                edesc->chained = chained;
                 edesc->sec4_sg_bytes = sec4_sg_bytes;
                 edesc->sec4_sg = (void *)edesc + sizeof(struct ahash_edesc) +
                                  DESC_JOB_IO_LEN;
@@ -1263,7 +1249,7 @@ static int ahash_update_no_ctx(struct ahash_request *req)
                 state->buf_dma = buf_map_to_sec4_sg(jrdev, edesc->sec4_sg,
                                                     buf, *buflen);
                 src_map_to_sec4_sg(jrdev, req->src, src_nents,
-                                   edesc->sec4_sg + 1, chained);
+                                   edesc->sec4_sg + 1);
                 if (*next_buflen) {
                         scatterwalk_map_and_copy(next_buf, req->src,
                                                  to_hash - *buflen,
@@ -1343,11 +1329,10 @@ static int ahash_finup_no_ctx(struct ahash_request *req)
         int sec4_sg_bytes, sec4_sg_src_index, src_nents;
         int digestsize = crypto_ahash_digestsize(ahash);
         struct ahash_edesc *edesc;
-        bool chained = false;
         int sh_len;
         int ret = 0;
 
-        src_nents = __sg_count(req->src, req->nbytes, &chained);
+        src_nents = sg_nents_for_len(req->src, req->nbytes);
         sec4_sg_src_index = 2;
         sec4_sg_bytes = (sec4_sg_src_index + src_nents) *
                          sizeof(struct sec4_sg_entry);
@@ -1365,7 +1350,6 @@ static int ahash_finup_no_ctx(struct ahash_request *req)
         init_job_desc_shared(desc, ptr, sh_len, HDR_SHARE_DEFER | HDR_REVERSE);
 
         edesc->src_nents = src_nents;
-        edesc->chained = chained;
         edesc->sec4_sg_bytes = sec4_sg_bytes;
         edesc->sec4_sg = (void *)edesc + sizeof(struct ahash_edesc) +
                          DESC_JOB_IO_LEN;
@@ -1374,8 +1358,7 @@ static int ahash_finup_no_ctx(struct ahash_request *req)
                                                 state->buf_dma, buflen,
                                                 last_buflen);
 
-        src_map_to_sec4_sg(jrdev, req->src, src_nents, edesc->sec4_sg + 1,
-                           chained);
+        src_map_to_sec4_sg(jrdev, req->src, src_nents, edesc->sec4_sg + 1);
 
         edesc->sec4_sg_dma = dma_map_single(jrdev, edesc->sec4_sg,
                                             sec4_sg_bytes, DMA_TO_DEVICE);
@@ -1429,7 +1412,6 @@ static int ahash_update_first(struct ahash_request *req)
         dma_addr_t src_dma;
         u32 options;
         struct ahash_edesc *edesc;
-        bool chained = false;
         int ret = 0;
         int sh_len;
 
@@ -1438,10 +1420,8 @@ static int ahash_update_first(struct ahash_request *req)
         to_hash = req->nbytes - *next_buflen;
 
         if (to_hash) {
-                src_nents = sg_count(req->src, req->nbytes - (*next_buflen),
-                                     &chained);
-                dma_map_sg_chained(jrdev, req->src, src_nents ? : 1,
-                                   DMA_TO_DEVICE, chained);
+                src_nents = sg_count(req->src, req->nbytes - (*next_buflen));
+                dma_map_sg(jrdev, req->src, src_nents ? : 1, DMA_TO_DEVICE);
                 sec4_sg_bytes = src_nents * sizeof(struct sec4_sg_entry);
 
                 /*
@@ -1457,7 +1437,6 @@ static int ahash_update_first(struct ahash_request *req)
                 }
 
                 edesc->src_nents = src_nents;
-                edesc->chained = chained;
                 edesc->sec4_sg_bytes = sec4_sg_bytes;
                 edesc->sec4_sg = (void *)edesc + sizeof(struct ahash_edesc) +
                                  DESC_JOB_IO_LEN;
diff --git a/drivers/crypto/caam/sg_sw_sec4.h b/drivers/crypto/caam/sg_sw_sec4.h
index 18cd6d1f5870..12ec6616e89d 100644
--- a/drivers/crypto/caam/sg_sw_sec4.h
+++ b/drivers/crypto/caam/sg_sw_sec4.h
@@ -69,81 +69,13 @@ static inline struct sec4_sg_entry *sg_to_sec4_sg_len(
         return sec4_sg_ptr - 1;
 }
 
-/* count number of elements in scatterlist */
-static inline int __sg_count(struct scatterlist *sg_list, int nbytes,
-                             bool *chained)
-{
-        struct scatterlist *sg = sg_list;
-        int sg_nents = 0;
-
-        while (nbytes > 0) {
-                sg_nents++;
-                nbytes -= sg->length;
-                if (!sg_is_last(sg) && (sg + 1)->length == 0)
-                        *chained = true;
-                sg = sg_next(sg);
-        }
-
-        return sg_nents;
-}
-
 /* derive number of elements in scatterlist, but return 0 for 1 */
-static inline int sg_count(struct scatterlist *sg_list, int nbytes,
-                             bool *chained)
+static inline int sg_count(struct scatterlist *sg_list, int nbytes)
 {
-        int sg_nents = __sg_count(sg_list, nbytes, chained);
+        int sg_nents = sg_nents_for_len(sg_list, nbytes);
 
         if (likely(sg_nents == 1))
                 return 0;
 
         return sg_nents;
 }
-
-static inline void dma_unmap_sg_chained(
-        struct device *dev, struct scatterlist *sg, unsigned int nents,
-        enum dma_data_direction dir, bool chained)
-{
-        if (unlikely(chained)) {
-                int i;
-                struct scatterlist *tsg = sg;
-
-                /*
-                 * Use a local copy of the sg pointer to avoid moving the
-                 * head of the list pointed to by sg as we walk the list.
-                 */
-                for (i = 0; i < nents; i++) {
-                        dma_unmap_sg(dev, tsg, 1, dir);
-                        tsg = sg_next(tsg);
-                }
-        } else if (nents) {
-                dma_unmap_sg(dev, sg, nents, dir);
-        }
-}
-
-static inline int dma_map_sg_chained(
-        struct device *dev, struct scatterlist *sg, unsigned int nents,
-        enum dma_data_direction dir, bool chained)
-{
-        if (unlikely(chained)) {
-                int i;
-                struct scatterlist *tsg = sg;
-
-                /*
-                 * Use a local copy of the sg pointer to avoid moving the
-                 * head of the list pointed to by sg as we walk the list.
-                 */
-                for (i = 0; i < nents; i++) {
-                        if (!dma_map_sg(dev, tsg, 1, dir)) {
-                                dma_unmap_sg_chained(dev, sg, i, dir,
-                                                     chained);
-                                nents = 0;
-                                break;
-                        }
-
-                        tsg = sg_next(tsg);
-                }
-        } else
-                nents = dma_map_sg(dev, sg, nents, dir);
-
-        return nents;
-}