5 files changed, 238 insertions, 167 deletions

diff --git a/crypto/async_tx/async_memcpy.c b/crypto/async_tx/async_memcpy.c
index 9e62feffb374..f8c0b8dbeb75 100644
--- a/crypto/async_tx/async_memcpy.c
+++ b/crypto/async_tx/async_memcpy.c
@@ -50,33 +50,36 @@ async_memcpy(struct page *dest, struct page *src, unsigned int dest_offset,
                                                       &dest, 1, &src, 1, len);
         struct dma_device *device = chan ? chan->device : NULL;
         struct dma_async_tx_descriptor *tx = NULL;
+        struct dmaengine_unmap_data *unmap = NULL;
 
-        if (device && is_dma_copy_aligned(device, src_offset, dest_offset, len)) {
-                dma_addr_t dma_dest, dma_src;
+        if (device)
+                unmap = dmaengine_get_unmap_data(device->dev, 2, GFP_NOIO);
+
+        if (unmap && is_dma_copy_aligned(device, src_offset, dest_offset, len)) {
                 unsigned long dma_prep_flags = 0;
 
                 if (submit->cb_fn)
                         dma_prep_flags |= DMA_PREP_INTERRUPT;
                 if (submit->flags & ASYNC_TX_FENCE)
                         dma_prep_flags |= DMA_PREP_FENCE;
-                dma_dest = dma_map_page(device->dev, dest, dest_offset, len,
-                                        DMA_FROM_DEVICE);
-
-                dma_src = dma_map_page(device->dev, src, src_offset, len,
-                                       DMA_TO_DEVICE);
-
-                tx = device->device_prep_dma_memcpy(chan, dma_dest, dma_src,
-                                                    len, dma_prep_flags);
-                if (!tx) {
-                        dma_unmap_page(device->dev, dma_dest, len,
-                                       DMA_FROM_DEVICE);
-                        dma_unmap_page(device->dev, dma_src, len,
-                                       DMA_TO_DEVICE);
-                }
+
+                unmap->to_cnt = 1;
+                unmap->addr[0] = dma_map_page(device->dev, src, src_offset, len,
+                                              DMA_TO_DEVICE);
+                unmap->from_cnt = 1;
+                unmap->addr[1] = dma_map_page(device->dev, dest, dest_offset, len,
+                                              DMA_FROM_DEVICE);
+                unmap->len = len;
+
+                tx = device->device_prep_dma_memcpy(chan, unmap->addr[1],
+                                                    unmap->addr[0], len,
+                                                    dma_prep_flags);
         }
 
         if (tx) {
                 pr_debug("%s: (async) len: %zu\n", __func__, len);
+
+                dma_set_unmap(tx, unmap);
                 async_tx_submit(chan, tx, submit);
         } else {
                 void *dest_buf, *src_buf;
@@ -96,6 +99,8 @@ async_memcpy(struct page *dest, struct page *src, unsigned int dest_offset,
                 async_tx_sync_epilog(submit);
         }
 
+        dmaengine_unmap_put(unmap);
+
         return tx;
 }
 EXPORT_SYMBOL_GPL(async_memcpy);
diff --git a/crypto/async_tx/async_pq.c b/crypto/async_tx/async_pq.c
index 91d5d385899e..d05327caf69d 100644
--- a/crypto/async_tx/async_pq.c
+++ b/crypto/async_tx/async_pq.c
@@ -46,49 +46,24 @@ static struct page *pq_scribble_page;
  * do_async_gen_syndrome - asynchronously calculate P and/or Q
  */
 static __async_inline struct dma_async_tx_descriptor *
-do_async_gen_syndrome(struct dma_chan *chan, struct page **blocks,
-                      const unsigned char *scfs, unsigned int offset, int disks,
-                      size_t len, dma_addr_t *dma_src,
+do_async_gen_syndrome(struct dma_chan *chan,
+                      const unsigned char *scfs, int disks,
+                      struct dmaengine_unmap_data *unmap,
+                      enum dma_ctrl_flags dma_flags,
                       struct async_submit_ctl *submit)
 {
         struct dma_async_tx_descriptor *tx = NULL;
         struct dma_device *dma = chan->device;
-        enum dma_ctrl_flags dma_flags = 0;
         enum async_tx_flags flags_orig = submit->flags;
         dma_async_tx_callback cb_fn_orig = submit->cb_fn;
         dma_async_tx_callback cb_param_orig = submit->cb_param;
         int src_cnt = disks - 2;
-        unsigned char coefs[src_cnt];
         unsigned short pq_src_cnt;
         dma_addr_t dma_dest[2];
         int src_off = 0;
-        int idx;
-        int i;
 
-        /* DMAs use destinations as sources, so use BIDIRECTIONAL mapping */
-        if (P(blocks, disks))
-                dma_dest[0] = dma_map_page(dma->dev, P(blocks, disks), offset,
-                                           len, DMA_BIDIRECTIONAL);
-        else
-                dma_flags |= DMA_PREP_PQ_DISABLE_P;
-        if (Q(blocks, disks))
-                dma_dest[1] = dma_map_page(dma->dev, Q(blocks, disks), offset,
-                                           len, DMA_BIDIRECTIONAL);
-        else
-                dma_flags |= DMA_PREP_PQ_DISABLE_Q;
-
-        /* convert source addresses being careful to collapse 'empty'
-         * sources and update the coefficients accordingly
-         */
-        for (i = 0, idx = 0; i < src_cnt; i++) {
-                if (blocks[i] == NULL)
-                        continue;
-                dma_src[idx] = dma_map_page(dma->dev, blocks[i], offset, len,
-                                            DMA_TO_DEVICE);
-                coefs[idx] = scfs[i];
-                idx++;
-        }
-        src_cnt = idx;
+        if (submit->flags & ASYNC_TX_FENCE)
+                dma_flags |= DMA_PREP_FENCE;
 
         while (src_cnt > 0) {
                 submit->flags = flags_orig;
@@ -100,28 +75,25 @@ do_async_gen_syndrome(struct dma_chan *chan, struct page **blocks,
                 if (src_cnt > pq_src_cnt) {
                         submit->flags &= ~ASYNC_TX_ACK;
                         submit->flags |= ASYNC_TX_FENCE;
-                        dma_flags |= DMA_COMPL_SKIP_DEST_UNMAP;
                         submit->cb_fn = NULL;
                         submit->cb_param = NULL;
                 } else {
-                        dma_flags &= ~DMA_COMPL_SKIP_DEST_UNMAP;
                         submit->cb_fn = cb_fn_orig;
                         submit->cb_param = cb_param_orig;
                         if (cb_fn_orig)
                                 dma_flags |= DMA_PREP_INTERRUPT;
                 }
-                if (submit->flags & ASYNC_TX_FENCE)
-                        dma_flags |= DMA_PREP_FENCE;
 
-                /* Since we have clobbered the src_list we are committed
-                 * to doing this asynchronously.  Drivers force forward
-                 * progress in case they can not provide a descriptor
+                /* Drivers force forward progress in case they can not provide
+                 * a descriptor
                  */
                 for (;;) {
+                        dma_dest[0] = unmap->addr[disks - 2];
+                        dma_dest[1] = unmap->addr[disks - 1];
                         tx = dma->device_prep_dma_pq(chan, dma_dest,
-                                                     &dma_src[src_off],
+                                                     &unmap->addr[src_off],
                                                      pq_src_cnt,
-                                                     &coefs[src_off], len,
+                                                     &scfs[src_off], unmap->len,
                                                      dma_flags);
                         if (likely(tx))
                                 break;
@@ -129,6 +101,7 @@ do_async_gen_syndrome(struct dma_chan *chan, struct page **blocks,
                         dma_async_issue_pending(chan);
                 }
 
+                dma_set_unmap(tx, unmap);
                 async_tx_submit(chan, tx, submit);
                 submit->depend_tx = tx;
 
@@ -188,10 +161,6 @@ do_sync_gen_syndrome(struct page **blocks, unsigned int offset, int disks,
  * set to NULL those buffers will be replaced with the raid6_zero_page
  * in the synchronous path and omitted in the hardware-asynchronous
  * path.
- *
- * 'blocks' note: if submit->scribble is NULL then the contents of
- * 'blocks' may be overwritten to perform address conversions
- * (dma_map_page() or page_address()).
  */
 struct dma_async_tx_descriptor *
 async_gen_syndrome(struct page **blocks, unsigned int offset, int disks,
@@ -202,26 +171,69 @@ async_gen_syndrome(struct page **blocks, unsigned int offset, int disks,
                                                       &P(blocks, disks), 2,
                                                       blocks, src_cnt, len);
         struct dma_device *device = chan ? chan->device : NULL;
-        dma_addr_t *dma_src = NULL;
+        struct dmaengine_unmap_data *unmap = NULL;
 
         BUG_ON(disks > 255 || !(P(blocks, disks) || Q(blocks, disks)));
 
-        if (submit->scribble)
-                dma_src = submit->scribble;
-        else if (sizeof(dma_addr_t) <= sizeof(struct page *))
-                dma_src = (dma_addr_t *) blocks;
+        if (device)
+                unmap = dmaengine_get_unmap_data(device->dev, disks, GFP_NOIO);
 
-        if (dma_src && device &&
+        if (unmap &&
             (src_cnt <= dma_maxpq(device, 0) ||
              dma_maxpq(device, DMA_PREP_CONTINUE) > 0) &&
             is_dma_pq_aligned(device, offset, 0, len)) {
+                struct dma_async_tx_descriptor *tx;
+                enum dma_ctrl_flags dma_flags = 0;
+                unsigned char coefs[src_cnt];
+                int i, j;
+
                 /* run the p+q asynchronously */
                 pr_debug("%s: (async) disks: %d len: %zu\n",
                          __func__, disks, len);
-                return do_async_gen_syndrome(chan, blocks, raid6_gfexp, offset,
-                                             disks, len, dma_src, submit);
+
+                /* convert source addresses being careful to collapse 'empty'
+                 * sources and update the coefficients accordingly
+                 */
+                unmap->len = len;
+                for (i = 0, j = 0; i < src_cnt; i++) {
+                        if (blocks[i] == NULL)
+                                continue;
+                        unmap->addr[j] = dma_map_page(device->dev, blocks[i], offset,
+                                                      len, DMA_TO_DEVICE);
+                        coefs[j] = raid6_gfexp[i];
+                        unmap->to_cnt++;
+                        j++;
+                }
+
+                /*
+                 * DMAs use destinations as sources,
+                 * so use BIDIRECTIONAL mapping
+                 */
+                unmap->bidi_cnt++;
+                if (P(blocks, disks))
+                        unmap->addr[j++] = dma_map_page(device->dev, P(blocks, disks),
+                                                        offset, len, DMA_BIDIRECTIONAL);
+                else {
+                        unmap->addr[j++] = 0;
+                        dma_flags |= DMA_PREP_PQ_DISABLE_P;
+                }
+
+                unmap->bidi_cnt++;
+                if (Q(blocks, disks))
+                        unmap->addr[j++] = dma_map_page(device->dev, Q(blocks, disks),
+                                                       offset, len, DMA_BIDIRECTIONAL);
+                else {
+                        unmap->addr[j++] = 0;
+                        dma_flags |= DMA_PREP_PQ_DISABLE_Q;
+                }
+
+                tx = do_async_gen_syndrome(chan, coefs, j, unmap, dma_flags, submit);
+                dmaengine_unmap_put(unmap);
+                return tx;
         }
 
+        dmaengine_unmap_put(unmap);
+
         /* run the pq synchronously */
         pr_debug("%s: (sync) disks: %d len: %zu\n", __func__, disks, len);
 
@@ -277,50 +289,60 @@ async_syndrome_val(struct page **blocks, unsigned int offset, int disks,
         struct dma_async_tx_descriptor *tx;
         unsigned char coefs[disks-2];
         enum dma_ctrl_flags dma_flags = submit->cb_fn ? DMA_PREP_INTERRUPT : 0;
-        dma_addr_t *dma_src = NULL;
-        int src_cnt = 0;
+        struct dmaengine_unmap_data *unmap = NULL;
 
         BUG_ON(disks < 4);
 
-        if (submit->scribble)
-                dma_src = submit->scribble;
-        else if (sizeof(dma_addr_t) <= sizeof(struct page *))
-                dma_src = (dma_addr_t *) blocks;
+        if (device)
+                unmap = dmaengine_get_unmap_data(device->dev, disks, GFP_NOIO);
 
-        if (dma_src && device && disks <= dma_maxpq(device, 0) &&
+        if (unmap && disks <= dma_maxpq(device, 0) &&
             is_dma_pq_aligned(device, offset, 0, len)) {
                 struct device *dev = device->dev;
-                dma_addr_t *pq = &dma_src[disks-2];
-                int i;
+                dma_addr_t pq[2];
+                int i, j = 0, src_cnt = 0;
 
                 pr_debug("%s: (async) disks: %d len: %zu\n",
                          __func__, disks, len);
-                if (!P(blocks, disks))
+
+                unmap->len = len;
+                for (i = 0; i < disks-2; i++)
+                        if (likely(blocks[i])) {
+                                unmap->addr[j] = dma_map_page(dev, blocks[i],
+                                                              offset, len,
+                                                              DMA_TO_DEVICE);
+                                coefs[j] = raid6_gfexp[i];
+                                unmap->to_cnt++;
+                                src_cnt++;
+                                j++;
+                        }
+
+                if (!P(blocks, disks)) {
+                        pq[0] = 0;
                         dma_flags |= DMA_PREP_PQ_DISABLE_P;
-                else
+                } else {
                         pq[0] = dma_map_page(dev, P(blocks, disks),
                                              offset, len,
                                              DMA_TO_DEVICE);
-                if (!Q(blocks, disks))
+                        unmap->addr[j++] = pq[0];
+                        unmap->to_cnt++;
+                }
+                if (!Q(blocks, disks)) {
+                        pq[1] = 0;
                         dma_flags |= DMA_PREP_PQ_DISABLE_Q;
-                else
+                } else {
                         pq[1] = dma_map_page(dev, Q(blocks, disks),
                                              offset, len,
                                              DMA_TO_DEVICE);
+                        unmap->addr[j++] = pq[1];
+                        unmap->to_cnt++;
+                }
 
                 if (submit->flags & ASYNC_TX_FENCE)
                         dma_flags |= DMA_PREP_FENCE;
-                for (i = 0; i < disks-2; i++)
-                        if (likely(blocks[i])) {
-                                dma_src[src_cnt] = dma_map_page(dev, blocks[i],
-                                                                offset, len,
-                                                                DMA_TO_DEVICE);
-                                coefs[src_cnt] = raid6_gfexp[i];
-                                src_cnt++;
-                        }
-
                 for (;;) {
-                        tx = device->device_prep_dma_pq_val(chan, pq, dma_src,
+                        tx = device->device_prep_dma_pq_val(chan, pq,
+                                                            unmap->addr,
                                                             src_cnt,
                                                             coefs,
                                                             len, pqres,
@@ -330,6 +352,8 @@ async_syndrome_val(struct page **blocks, unsigned int offset, int disks,
                         async_tx_quiesce(&submit->depend_tx);
                         dma_async_issue_pending(chan);
                 }
+
+                dma_set_unmap(tx, unmap);
                 async_tx_submit(chan, tx, submit);
 
                 return tx;
diff --git a/crypto/async_tx/async_raid6_recov.c b/crypto/async_tx/async_raid6_recov.c
index a9f08a6a582e..934a84981495 100644
--- a/crypto/async_tx/async_raid6_recov.c
+++ b/crypto/async_tx/async_raid6_recov.c
@@ -26,6 +26,7 @@
 #include <linux/dma-mapping.h>
 #include <linux/raid/pq.h>
 #include <linux/async_tx.h>
+#include <linux/dmaengine.h>
 
 static struct dma_async_tx_descriptor *
 async_sum_product(struct page *dest, struct page **srcs, unsigned char *coef,
@@ -34,35 +35,45 @@ async_sum_product(struct page *dest, struct page **srcs, unsigned char *coef,
         struct dma_chan *chan = async_tx_find_channel(submit, DMA_PQ,
                                                       &dest, 1, srcs, 2, len);
         struct dma_device *dma = chan ? chan->device : NULL;
+        struct dmaengine_unmap_data *unmap = NULL;
         const u8 *amul, *bmul;
         u8 ax, bx;
         u8 *a, *b, *c;
 
-        if (dma) {
-                dma_addr_t dma_dest[2];
-                dma_addr_t dma_src[2];
+        if (dma)
+                unmap = dmaengine_get_unmap_data(dma->dev, 3, GFP_NOIO);
+
+        if (unmap) {
                 struct device *dev = dma->dev;
+                dma_addr_t pq[2];
                 struct dma_async_tx_descriptor *tx;
                 enum dma_ctrl_flags dma_flags = DMA_PREP_PQ_DISABLE_P;
 
                 if (submit->flags & ASYNC_TX_FENCE)
                         dma_flags |= DMA_PREP_FENCE;
-                dma_dest[1] = dma_map_page(dev, dest, 0, len, DMA_BIDIRECTIONAL);
-                dma_src[0] = dma_map_page(dev, srcs[0], 0, len, DMA_TO_DEVICE);
-                dma_src[1] = dma_map_page(dev, srcs[1], 0, len, DMA_TO_DEVICE);
-                tx = dma->device_prep_dma_pq(chan, dma_dest, dma_src, 2, coef,
+                unmap->addr[0] = dma_map_page(dev, srcs[0], 0, len, DMA_TO_DEVICE);
+                unmap->addr[1] = dma_map_page(dev, srcs[1], 0, len, DMA_TO_DEVICE);
+                unmap->to_cnt = 2;
+
+                unmap->addr[2] = dma_map_page(dev, dest, 0, len, DMA_BIDIRECTIONAL);
+                unmap->bidi_cnt = 1;
+                /* engine only looks at Q, but expects it to follow P */
+                pq[1] = unmap->addr[2];
+
+                unmap->len = len;
+                tx = dma->device_prep_dma_pq(chan, pq, unmap->addr, 2, coef,
                                              len, dma_flags);
                 if (tx) {
+                        dma_set_unmap(tx, unmap);
                         async_tx_submit(chan, tx, submit);
+                        dmaengine_unmap_put(unmap);
                         return tx;
                 }
 
                 /* could not get a descriptor, unmap and fall through to
                  * the synchronous path
                  */
-                dma_unmap_page(dev, dma_dest[1], len, DMA_BIDIRECTIONAL);
-                dma_unmap_page(dev, dma_src[0], len, DMA_TO_DEVICE);
-                dma_unmap_page(dev, dma_src[1], len, DMA_TO_DEVICE);
+                dmaengine_unmap_put(unmap);
         }
 
         /* run the operation synchronously */
@@ -89,23 +100,38 @@ async_mult(struct page *dest, struct page *src, u8 coef, size_t len,
         struct dma_chan *chan = async_tx_find_channel(submit, DMA_PQ,
                                                       &dest, 1, &src, 1, len);
         struct dma_device *dma = chan ? chan->device : NULL;
+        struct dmaengine_unmap_data *unmap = NULL;
         const u8 *qmul; /* Q multiplier table */
         u8 *d, *s;
 
-        if (dma) {
+        if (dma)
+                unmap = dmaengine_get_unmap_data(dma->dev, 3, GFP_NOIO);
+
+        if (unmap) {
                 dma_addr_t dma_dest[2];
-                dma_addr_t dma_src[1];
                 struct device *dev = dma->dev;
                 struct dma_async_tx_descriptor *tx;
                 enum dma_ctrl_flags dma_flags = DMA_PREP_PQ_DISABLE_P;
 
                 if (submit->flags & ASYNC_TX_FENCE)
                         dma_flags |= DMA_PREP_FENCE;
-                dma_dest[1] = dma_map_page(dev, dest, 0, len, DMA_BIDIRECTIONAL);
-                dma_src[0] = dma_map_page(dev, src, 0, len, DMA_TO_DEVICE);
-                tx = dma->device_prep_dma_pq(chan, dma_dest, dma_src, 1, &coef,
-                                             len, dma_flags);
+                unmap->addr[0] = dma_map_page(dev, src, 0, len, DMA_TO_DEVICE);
+                unmap->to_cnt++;
+                unmap->addr[1] = dma_map_page(dev, dest, 0, len, DMA_BIDIRECTIONAL);
+                dma_dest[1] = unmap->addr[1];
+                unmap->bidi_cnt++;
+                unmap->len = len;
+
+                /* this looks funny, but the engine looks for Q at
+                 * dma_dest[1] and ignores dma_dest[0] as a dest
+                 * due to DMA_PREP_PQ_DISABLE_P
+                 */
+                tx = dma->device_prep_dma_pq(chan, dma_dest, unmap->addr,
+                                             1, &coef, len, dma_flags);
+
                 if (tx) {
+                        dma_set_unmap(tx, unmap);
+                        dmaengine_unmap_put(unmap);
                         async_tx_submit(chan, tx, submit);
                         return tx;
                 }
@@ -113,8 +139,7 @@ async_mult(struct page *dest, struct page *src, u8 coef, size_t len,
                 /* could not get a descriptor, unmap and fall through to
                  * the synchronous path
                  */
-                dma_unmap_page(dev, dma_dest[1], len, DMA_BIDIRECTIONAL);
-                dma_unmap_page(dev, dma_src[0], len, DMA_TO_DEVICE);
+                dmaengine_unmap_put(unmap);
         }
 
         /* no channel available, or failed to allocate a descriptor, so
diff --git a/crypto/async_tx/async_xor.c b/crypto/async_tx/async_xor.c
index 8ade0a0481c6..3c562f5a60bb 100644
--- a/crypto/async_tx/async_xor.c
+++ b/crypto/async_tx/async_xor.c
@@ -33,48 +33,31 @@
 
 /* do_async_xor - dma map the pages and perform the xor with an engine */
 static __async_inline struct dma_async_tx_descriptor *
-do_async_xor(struct dma_chan *chan, struct page *dest, struct page **src_list,
-             unsigned int offset, int src_cnt, size_t len, dma_addr_t *dma_src,
+do_async_xor(struct dma_chan *chan, struct dmaengine_unmap_data *unmap,
              struct async_submit_ctl *submit)
 {
         struct dma_device *dma = chan->device;
         struct dma_async_tx_descriptor *tx = NULL;
-        int src_off = 0;
-        int i;
         dma_async_tx_callback cb_fn_orig = submit->cb_fn;
         void *cb_param_orig = submit->cb_param;
         enum async_tx_flags flags_orig = submit->flags;
-        enum dma_ctrl_flags dma_flags;
-        int xor_src_cnt = 0;
-        dma_addr_t dma_dest;
-
-        /* map the dest bidrectional in case it is re-used as a source */
-        dma_dest = dma_map_page(dma->dev, dest, offset, len, DMA_BIDIRECTIONAL);
-        for (i = 0; i < src_cnt; i++) {
-                /* only map the dest once */
-                if (!src_list[i])
-                        continue;
-                if (unlikely(src_list[i] == dest)) {
-                        dma_src[xor_src_cnt++] = dma_dest;
-                        continue;
-                }
-                dma_src[xor_src_cnt++] = dma_map_page(dma->dev, src_list[i], offset,
-                                                      len, DMA_TO_DEVICE);
-        }
-        src_cnt = xor_src_cnt;
+        enum dma_ctrl_flags dma_flags = 0;
+        int src_cnt = unmap->to_cnt;
+        int xor_src_cnt;
+        dma_addr_t dma_dest = unmap->addr[unmap->to_cnt];
+        dma_addr_t *src_list = unmap->addr;
 
         while (src_cnt) {
+                dma_addr_t tmp;
+
                 submit->flags = flags_orig;
-                dma_flags = 0;
                 xor_src_cnt = min(src_cnt, (int)dma->max_xor);
-                /* if we are submitting additional xors, leave the chain open,
-                 * clear the callback parameters, and leave the destination
-                 * buffer mapped
+                /* if we are submitting additional xors, leave the chain open
+                 * and clear the callback parameters
                  */
                 if (src_cnt > xor_src_cnt) {
                         submit->flags &= ~ASYNC_TX_ACK;
                         submit->flags |= ASYNC_TX_FENCE;
-                        dma_flags = DMA_COMPL_SKIP_DEST_UNMAP;
                         submit->cb_fn = NULL;
                         submit->cb_param = NULL;
                 } else {
@@ -85,12 +68,18 @@ do_async_xor(struct dma_chan *chan, struct page *dest, struct page **src_list,
                         dma_flags |= DMA_PREP_INTERRUPT;
                 if (submit->flags & ASYNC_TX_FENCE)
                         dma_flags |= DMA_PREP_FENCE;
-                /* Since we have clobbered the src_list we are committed
-                 * to doing this asynchronously.  Drivers force forward progress
-                 * in case they can not provide a descriptor
+
+                /* Drivers force forward progress in case they can not provide a
+                 * descriptor
                  */
-                tx = dma->device_prep_dma_xor(chan, dma_dest, &dma_src[src_off],
-                                              xor_src_cnt, len, dma_flags);
+                tmp = src_list[0];
+                if (src_list > unmap->addr)
+                        src_list[0] = dma_dest;
+                tx = dma->device_prep_dma_xor(chan, dma_dest, src_list,
+                                              xor_src_cnt, unmap->len,
+                                              dma_flags);
+                src_list[0] = tmp;
+
 
                 if (unlikely(!tx))
                         async_tx_quiesce(&submit->depend_tx);
@@ -99,22 +88,21 @@ do_async_xor(struct dma_chan *chan, struct page *dest, struct page **src_list,
                 while (unlikely(!tx)) {
                         dma_async_issue_pending(chan);
                         tx = dma->device_prep_dma_xor(chan, dma_dest,
-                                                      &dma_src[src_off],
-                                                      xor_src_cnt, len,
+                                                      src_list,
+                                                      xor_src_cnt, unmap->len,
                                                       dma_flags);
                 }
 
+                dma_set_unmap(tx, unmap);
                 async_tx_submit(chan, tx, submit);
                 submit->depend_tx = tx;
 
                 if (src_cnt > xor_src_cnt) {
                         /* drop completed sources */
                         src_cnt -= xor_src_cnt;
-                        src_off += xor_src_cnt;
-
                         /* use the intermediate result a source */
-                        dma_src[--src_off] = dma_dest;
                         src_cnt++;
+                        src_list += xor_src_cnt - 1;
                 } else
                         break;
         }
@@ -189,22 +177,40 @@ async_xor(struct page *dest, struct page **src_list, unsigned int offset,
         struct dma_chan *chan = async_tx_find_channel(submit, DMA_XOR,
                                                       &dest, 1, src_list,
                                                       src_cnt, len);
-        dma_addr_t *dma_src = NULL;
+        struct dma_device *device = chan ? chan->device : NULL;
+        struct dmaengine_unmap_data *unmap = NULL;
 
         BUG_ON(src_cnt <= 1);
 
-        if (submit->scribble)
-                dma_src = submit->scribble;
-        else if (sizeof(dma_addr_t) <= sizeof(struct page *))
-                dma_src = (dma_addr_t *) src_list;
+        if (device)
+                unmap = dmaengine_get_unmap_data(device->dev, src_cnt+1, GFP_NOIO);
+
+        if (unmap && is_dma_xor_aligned(device, offset, 0, len)) {
+                struct dma_async_tx_descriptor *tx;
+                int i, j;
 
-        if (dma_src && chan && is_dma_xor_aligned(chan->device, offset, 0, len)) {
                 /* run the xor asynchronously */
                 pr_debug("%s (async): len: %zu\n", __func__, len);
 
-                return do_async_xor(chan, dest, src_list, offset, src_cnt, len,
-                                    dma_src, submit);
+                unmap->len = len;
+                for (i = 0, j = 0; i < src_cnt; i++) {
+                        if (!src_list[i])
+                                continue;
+                        unmap->to_cnt++;
+                        unmap->addr[j++] = dma_map_page(device->dev, src_list[i],
+                                                        offset, len, DMA_TO_DEVICE);
+                }
+
+                /* map it bidirectional as it may be re-used as a source */
+                unmap->addr[j] = dma_map_page(device->dev, dest, offset, len,
+                                              DMA_BIDIRECTIONAL);
+                unmap->bidi_cnt = 1;
+
+                tx = do_async_xor(chan, unmap, submit);
+                dmaengine_unmap_put(unmap);
+                return tx;
         } else {
+                dmaengine_unmap_put(unmap);
                 /* run the xor synchronously */
                 pr_debug("%s (sync): len: %zu\n", __func__, len);
                 WARN_ONCE(chan, "%s: no space for dma address conversion\n",
@@ -268,16 +274,14 @@ async_xor_val(struct page *dest, struct page **src_list, unsigned int offset,
         struct dma_chan *chan = xor_val_chan(submit, dest, src_list, src_cnt, len);
         struct dma_device *device = chan ? chan->device : NULL;
         struct dma_async_tx_descriptor *tx = NULL;
-        dma_addr_t *dma_src = NULL;
+        struct dmaengine_unmap_data *unmap = NULL;
 
         BUG_ON(src_cnt <= 1);
 
-        if (submit->scribble)
-                dma_src = submit->scribble;
-        else if (sizeof(dma_addr_t) <= sizeof(struct page *))
-                dma_src = (dma_addr_t *) src_list;
+        if (device)
+                unmap = dmaengine_get_unmap_data(device->dev, src_cnt, GFP_NOIO);
 
-        if (dma_src && device && src_cnt <= device->max_xor &&
+        if (unmap && src_cnt <= device->max_xor &&
             is_dma_xor_aligned(device, offset, 0, len)) {
                 unsigned long dma_prep_flags = 0;
                 int i;
@@ -288,11 +292,15 @@ async_xor_val(struct page *dest, struct page **src_list, unsigned int offset,
                         dma_prep_flags |= DMA_PREP_INTERRUPT;
                 if (submit->flags & ASYNC_TX_FENCE)
                         dma_prep_flags |= DMA_PREP_FENCE;
-                for (i = 0; i < src_cnt; i++)
-                        dma_src[i] = dma_map_page(device->dev, src_list[i],
-                                                  offset, len, DMA_TO_DEVICE);
 
-                tx = device->device_prep_dma_xor_val(chan, dma_src, src_cnt,
+                for (i = 0; i < src_cnt; i++) {
+                        unmap->addr[i] = dma_map_page(device->dev, src_list[i],
+                                                      offset, len, DMA_TO_DEVICE);
+                        unmap->to_cnt++;
+                }
+                unmap->len = len;
+
+                tx = device->device_prep_dma_xor_val(chan, unmap->addr, src_cnt,
                                                      len, result,
                                                      dma_prep_flags);
                 if (unlikely(!tx)) {
@@ -301,11 +309,11 @@ async_xor_val(struct page *dest, struct page **src_list, unsigned int offset,
                         while (!tx) {
                                 dma_async_issue_pending(chan);
                                 tx = device->device_prep_dma_xor_val(chan,
-                                        dma_src, src_cnt, len, result,
+                                        unmap->addr, src_cnt, len, result,
                                         dma_prep_flags);
                         }
                 }
-
+                dma_set_unmap(tx, unmap);
                 async_tx_submit(chan, tx, submit);
         } else {
                 enum async_tx_flags flags_orig = submit->flags;
@@ -327,6 +335,7 @@ async_xor_val(struct page *dest, struct page **src_list, unsigned int offset,
                 async_tx_sync_epilog(submit);
                 submit->flags = flags_orig;
         }
+        dmaengine_unmap_put(unmap);
 
         return tx;
 }
diff --git a/crypto/async_tx/raid6test.c b/crypto/async_tx/raid6test.c
index 4a92bac744dc..dad95f45b88f 100644
--- a/crypto/async_tx/raid6test.c
+++ b/crypto/async_tx/raid6test.c
@@ -28,7 +28,7 @@
 #undef pr
 #define pr(fmt, args...) pr_info("raid6test: " fmt, ##args)
 
-#define NDISKS 16 /* Including P and Q */
+#define NDISKS 64 /* Including P and Q */
 
 static struct page *dataptrs[NDISKS];
 static addr_conv_t addr_conv[NDISKS];
@@ -219,6 +219,14 @@ static int raid6_test(void)
                 err += test(11, &tests);
                 err += test(12, &tests);
         }
+
+        /* the 24 disk case is special for ioatdma as it is the boudary point
+         * at which it needs to switch from 8-source ops to 16-source
+         * ops for continuation (assumes DMA_HAS_PQ_CONTINUE is not set)
+         */
+        if (NDISKS > 24)
+                err += test(24, &tests);
+
         err += test(NDISKS, &tests);
 
         pr("\n");