dma: mv_xor: Use dmaengine_unmap_data for the self-tests

The driver-specific unmap code was removed in:

  commit 54f8d501e842879143e867e70996574a54d1e130
  Author: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
  Date:   Fri Oct 18 19:35:32 2013 +0200

      dmaengine: remove DMA unmap from drivers

which had the side-effect of not unmapping the self-test mappings.
Fix this by using dmaengine_unmap_data in the self-test routines.

In addition, since dmaengine_unmap() assumes that all mappings were created
with dma_map_page, this commit changes the single mapping to a page mapping
to avoid an incorrect unmapping of the memcpy self-test.

The allocation could be changed to be alloc_page(), but sticking to kmalloc
results in a less intrusive patch. The size of the test buffer is increased,
since dma_map_page() seem to fail when the source and destination pages are
the same page.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

1 files changed, 50 insertions, 21 deletions

diff --git a/drivers/dma/mv_xor.c b/drivers/dma/mv_xor.c
index 23bcc9158cbc..79620887d637 100644
--- a/drivers/dma/mv_xor.c
+++ b/drivers/dma/mv_xor.c
@@ -781,7 +781,6 @@ static void mv_xor_issue_pending(struct dma_chan *chan)
 /*
  * Perform a transaction to verify the HW works.
  */
-#define MV_XOR_TEST_SIZE 2000
 
 static int mv_xor_memcpy_self_test(struct mv_xor_chan *mv_chan)
 {
@@ -791,20 +790,21 @@ static int mv_xor_memcpy_self_test(struct mv_xor_chan *mv_chan)
         struct dma_chan *dma_chan;
         dma_cookie_t cookie;
         struct dma_async_tx_descriptor *tx;
+        struct dmaengine_unmap_data *unmap;
         int err = 0;
 
-        src = kmalloc(sizeof(u8) * MV_XOR_TEST_SIZE, GFP_KERNEL);
+        src = kmalloc(sizeof(u8) * PAGE_SIZE, GFP_KERNEL);
         if (!src)
                 return -ENOMEM;
 
-        dest = kzalloc(sizeof(u8) * MV_XOR_TEST_SIZE, GFP_KERNEL);
+        dest = kzalloc(sizeof(u8) * PAGE_SIZE, GFP_KERNEL);
         if (!dest) {
                 kfree(src);
                 return -ENOMEM;
         }
 
         /* Fill in src buffer */
-        for (i = 0; i < MV_XOR_TEST_SIZE; i++)
+        for (i = 0; i < PAGE_SIZE; i++)
                 ((u8 *) src)[i] = (u8)i;
 
         dma_chan = &mv_chan->dmachan;
@@ -813,14 +813,26 @@ static int mv_xor_memcpy_self_test(struct mv_xor_chan *mv_chan)
                 goto out;
         }
 
-        dest_dma = dma_map_single(dma_chan->device->dev, dest,
-                                  MV_XOR_TEST_SIZE, DMA_FROM_DEVICE);
+        unmap = dmaengine_get_unmap_data(dma_chan->device->dev, 2, GFP_KERNEL);
+        if (!unmap) {
+                err = -ENOMEM;
+                goto free_resources;
+        }
+
+        src_dma = dma_map_page(dma_chan->device->dev, virt_to_page(src), 0,
+                                 PAGE_SIZE, DMA_TO_DEVICE);
+        unmap->to_cnt = 1;
+        unmap->addr[0] = src_dma;
 
-        src_dma = dma_map_single(dma_chan->device->dev, src,
-                                 MV_XOR_TEST_SIZE, DMA_TO_DEVICE);
+        dest_dma = dma_map_page(dma_chan->device->dev, virt_to_page(dest), 0,
+                                  PAGE_SIZE, DMA_FROM_DEVICE);
+        unmap->from_cnt = 1;
+        unmap->addr[1] = dest_dma;
+
+        unmap->len = PAGE_SIZE;
 
         tx = mv_xor_prep_dma_memcpy(dma_chan, dest_dma, src_dma,
-                                    MV_XOR_TEST_SIZE, 0);
+                                    PAGE_SIZE, 0);
         cookie = mv_xor_tx_submit(tx);
         mv_xor_issue_pending(dma_chan);
         async_tx_ack(tx);
@@ -835,8 +847,8 @@ static int mv_xor_memcpy_self_test(struct mv_xor_chan *mv_chan)
         }
 
         dma_sync_single_for_cpu(dma_chan->device->dev, dest_dma,
-                                MV_XOR_TEST_SIZE, DMA_FROM_DEVICE);
-        if (memcmp(src, dest, MV_XOR_TEST_SIZE)) {
+                                PAGE_SIZE, DMA_FROM_DEVICE);
+        if (memcmp(src, dest, PAGE_SIZE)) {
                 dev_err(dma_chan->device->dev,
                         "Self-test copy failed compare, disabling\n");
                 err = -ENODEV;
@@ -844,6 +856,7 @@ static int mv_xor_memcpy_self_test(struct mv_xor_chan *mv_chan)
         }
 
 free_resources:
+        dmaengine_unmap_put(unmap);
         mv_xor_free_chan_resources(dma_chan);
 out:
         kfree(src);
@@ -861,13 +874,15 @@ mv_xor_xor_self_test(struct mv_xor_chan *mv_chan)
         dma_addr_t dma_srcs[MV_XOR_NUM_SRC_TEST];
         dma_addr_t dest_dma;
         struct dma_async_tx_descriptor *tx;
+        struct dmaengine_unmap_data *unmap;
         struct dma_chan *dma_chan;
         dma_cookie_t cookie;
         u8 cmp_byte = 0;
         u32 cmp_word;
         int err = 0;
+        int src_count = MV_XOR_NUM_SRC_TEST;
 
-        for (src_idx = 0; src_idx < MV_XOR_NUM_SRC_TEST; src_idx++) {
+        for (src_idx = 0; src_idx < src_count; src_idx++) {
                 xor_srcs[src_idx] = alloc_page(GFP_KERNEL);
                 if (!xor_srcs[src_idx]) {
                         while (src_idx--)
@@ -884,13 +899,13 @@ mv_xor_xor_self_test(struct mv_xor_chan *mv_chan)
         }
 
         /* Fill in src buffers */
-        for (src_idx = 0; src_idx < MV_XOR_NUM_SRC_TEST; src_idx++) {
+        for (src_idx = 0; src_idx < src_count; src_idx++) {
                 u8 *ptr = page_address(xor_srcs[src_idx]);
                 for (i = 0; i < PAGE_SIZE; i++)
                         ptr[i] = (1 << src_idx);
         }
 
-        for (src_idx = 0; src_idx < MV_XOR_NUM_SRC_TEST; src_idx++)
+        for (src_idx = 0; src_idx < src_count; src_idx++)
                 cmp_byte ^= (u8) (1 << src_idx);
 
         cmp_word = (cmp_byte << 24) | (cmp_byte << 16) |
@@ -904,16 +919,29 @@ mv_xor_xor_self_test(struct mv_xor_chan *mv_chan)
                 goto out;
         }
 
+        unmap = dmaengine_get_unmap_data(dma_chan->device->dev, src_count + 1,
+                                         GFP_KERNEL);
+        if (!unmap) {
+                err = -ENOMEM;
+                goto free_resources;
+        }
+
         /* test xor */
-        dest_dma = dma_map_page(dma_chan->device->dev, dest, 0, PAGE_SIZE,
-                                DMA_FROM_DEVICE);
+        for (i = 0; i < src_count; i++) {
+                unmap->addr[i] = dma_map_page(dma_chan->device->dev, xor_srcs[i],
+                                              0, PAGE_SIZE, DMA_TO_DEVICE);
+                dma_srcs[i] = unmap->addr[i];
+                unmap->to_cnt++;
+        }
 
-        for (i = 0; i < MV_XOR_NUM_SRC_TEST; i++)
-                dma_srcs[i] = dma_map_page(dma_chan->device->dev, xor_srcs[i],
-                                           0, PAGE_SIZE, DMA_TO_DEVICE);
+        unmap->addr[src_count] = dma_map_page(dma_chan->device->dev, dest, 0, PAGE_SIZE,
+                                      DMA_FROM_DEVICE);
+        dest_dma = unmap->addr[src_count];
+        unmap->from_cnt = 1;
+        unmap->len = PAGE_SIZE;
 
         tx = mv_xor_prep_dma_xor(dma_chan, dest_dma, dma_srcs,
-                                 MV_XOR_NUM_SRC_TEST, PAGE_SIZE, 0);
+                                 src_count, PAGE_SIZE, 0);
 
         cookie = mv_xor_tx_submit(tx);
         mv_xor_issue_pending(dma_chan);
@@ -942,9 +970,10 @@ mv_xor_xor_self_test(struct mv_xor_chan *mv_chan)
         }
 
 free_resources:
+        dmaengine_unmap_put(unmap);
         mv_xor_free_chan_resources(dma_chan);
 out:
-        src_idx = MV_XOR_NUM_SRC_TEST;
+        src_idx = src_count;
         while (src_idx--)
                 __free_page(xor_srcs[src_idx]);
         __free_page(dest);