[PATCH 2/5] tm: Utilize the dma_addr_t array for pages that are to in DMA32 pool.

[Konrad Rzeszutek Wilk]

We only use the "if (pool == NULL)" path for right now.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk at oracle.com>
---
 drivers/gpu/drm/ttm/ttm_page_alloc.c |   26 +++++++++++++++++++++++---
 1 files changed, 23 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/ttm/ttm_page_alloc.c b/drivers/gpu/drm/ttm/ttm_page_alloc.c
index 6859288..5d09677 100644
--- a/drivers/gpu/drm/ttm/ttm_page_alloc.c
+++ b/drivers/gpu/drm/ttm/ttm_page_alloc.c
@@ -683,14 +683,22 @@ int ttm_get_pages(struct list_head *pages, int flags,
 			gfp_flags |= GFP_HIGHUSER;
 
 		for (r = 0; r < count; ++r) {
-			p = alloc_page(gfp_flags);
+			if ((flags & TTM_PAGE_FLAG_DMA32) && dma_address) {
+				void *addr;
+				addr = dma_alloc_coherent(NULL, PAGE_SIZE,
+							&dma_address[r],
+							gfp_flags);
+				if (addr == NULL)
+					return -ENOMEM;
+				p = virt_to_page(addr);
+			} else
+				p = alloc_page(gfp_flags);
 			if (!p) {
 
 				printk(KERN_ERR TTM_PFX
 				       "Unable to allocate page.");
 				return -ENOMEM;
 			}
-
 			list_add(&p->lru, pages);
 		}
 		return 0;
@@ -739,12 +747,24 @@ void ttm_put_pages(struct list_head *pages, unsigned page_count, int flags,
 	unsigned long irq_flags;
 	struct ttm_page_pool *pool = ttm_get_pool(flags, cstate);
 	struct page *p, *tmp;
+	unsigned r;
 
 	if (pool == NULL) {
 		/* No pool for this memory type so free the pages */
 
+		r = page_count-1;
 		list_for_each_entry_safe(p, tmp, pages, lru) {
-			__free_page(p);
+			if ((flags & TTM_PAGE_FLAG_DMA32) && dma_address) {
+				void *addr = page_address(p);
+				WARN_ON(!addr || !dma_address[r]);
+				if (addr)
+					dma_free_coherent(NULL, PAGE_SIZE,
+							addr,
+							dma_address[r]);
+				dma_address[r] = 0;
+			} else
+				__free_page(p);
+			r--;
 		}
 		/* Make the pages list empty */
 		INIT_LIST_HEAD(pages);
-- 
1.7.1