drm/ttm: DMA map/unmap consecutive pages as a whole v2

Instead of mapping them bit by bit map/unmap all consecutive
pages as in one call.

v2: test for consecutive pages instead of using compound page order.

Signed-off-by: Christian König <christian.koenig@amd.com>
Acked-by: Felix Kuehling <Felix.Kuehling@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 39 insertions, 9 deletions

diff --git a/drivers/gpu/drm/ttm/ttm_page_alloc.c b/drivers/gpu/drm/ttm/ttm_page_alloc.c
index 482dd9aa2c84..6c852e81660b 100644
--- a/drivers/gpu/drm/ttm/ttm_page_alloc.c
+++ b/drivers/gpu/drm/ttm/ttm_page_alloc.c
@@ -922,16 +922,26 @@ EXPORT_SYMBOL(ttm_pool_unpopulate);
 #if defined(CONFIG_SWIOTLB) || defined(CONFIG_INTEL_IOMMU)
 int ttm_populate_and_map_pages(struct device *dev, struct ttm_dma_tt *tt)
 {
-        unsigned i;
+        unsigned i, j;
         int r;
 
         r = ttm_pool_populate(&tt->ttm);
         if (r)
                 return r;
 
-        for (i = 0; i < tt->ttm.num_pages; i++) {
+        for (i = 0; i < tt->ttm.num_pages; ++i) {
+                struct page *p = tt->ttm.pages[i];
+                size_t num_pages = 1;
+
+                for (j = i + 1; j < tt->ttm.num_pages; ++j) {
+                        if (++p != tt->ttm.pages[j])
+                                break;
+
+                        ++num_pages;
+                }
+
                 tt->dma_address[i] = dma_map_page(dev, tt->ttm.pages[i],
-                                                  0, PAGE_SIZE,
+                                                  0, num_pages * PAGE_SIZE,
                                                   DMA_BIDIRECTIONAL);
                 if (dma_mapping_error(dev, tt->dma_address[i])) {
                         while (i--) {
@@ -942,6 +952,11 @@ int ttm_populate_and_map_pages(struct device *dev, struct ttm_dma_tt *tt)
                         ttm_pool_unpopulate(&tt->ttm);
                         return -EFAULT;
                 }
+
+                for (j = 1; j < num_pages; ++j) {
+                        tt->dma_address[i + 1] = tt->dma_address[i] + PAGE_SIZE;
+                        ++i;
+                }
         }
         return 0;
 }
@@ -949,13 +964,28 @@ EXPORT_SYMBOL(ttm_populate_and_map_pages);
 
 void ttm_unmap_and_unpopulate_pages(struct device *dev, struct ttm_dma_tt *tt)
 {
-        unsigned i;
-        
-        for (i = 0; i < tt->ttm.num_pages; i++) {
-                if (tt->dma_address[i]) {
-                        dma_unmap_page(dev, tt->dma_address[i],
-                                       PAGE_SIZE, DMA_BIDIRECTIONAL);
+        unsigned i, j;
+
+        for (i = 0; i < tt->ttm.num_pages;) {
+                struct page *p = tt->ttm.pages[i];
+                size_t num_pages = 1;
+
+                if (!tt->dma_address[i] || !tt->ttm.pages[i]) {
+                        ++i;
+                        continue;
                 }
+
+                for (j = i + 1; j < tt->ttm.num_pages; ++j) {
+                        if (++p != tt->ttm.pages[j])
+                                break;
+
+                        ++num_pages;
+                }
+
+                dma_unmap_page(dev, tt->dma_address[i], num_pages * PAGE_SIZE,
+                               DMA_BIDIRECTIONAL);
+
+                i += num_pages;
         }
         ttm_pool_unpopulate(&tt->ttm);
 }