drm/ttm: isolate dma data from ttm_tt V4

Move dma data to a superset ttm_dma_tt structure which herit
from ttm_tt. This allow driver that don't use dma functionalities
to not have to waste memory for it.

V2 Rebase on top of no memory account changes (where/when is my
   delorean when i need it ?)
V3 Make sure page list is initialized empty
V4 typo/syntax fixes

Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>

1 files changed, 49 insertions, 11 deletions

diff --git a/drivers/gpu/drm/ttm/ttm_tt.c b/drivers/gpu/drm/ttm/ttm_tt.c
index 1625739b434b..58e1fa14fe3a 100644
--- a/drivers/gpu/drm/ttm/ttm_tt.c
+++ b/drivers/gpu/drm/ttm/ttm_tt.c
@@ -48,17 +48,14 @@
  */
 static void ttm_tt_alloc_page_directory(struct ttm_tt *ttm)
 {
-	ttm->pages = drm_calloc_large(ttm->num_pages, sizeof(*ttm->pages));
-	ttm->dma_address = drm_calloc_large(ttm->num_pages,
-					    sizeof(*ttm->dma_address));
+	ttm->pages = drm_calloc_large(ttm->num_pages, sizeof(void*));
 }
 
-static void ttm_tt_free_page_directory(struct ttm_tt *ttm)
+static void ttm_dma_tt_alloc_page_directory(struct ttm_dma_tt *ttm)
 {
-	drm_free_large(ttm->pages);
-	ttm->pages = NULL;
-	drm_free_large(ttm->dma_address);
-	ttm->dma_address = NULL;
+	ttm->ttm.pages = drm_calloc_large(ttm->ttm.num_pages, sizeof(void*));
+	ttm->dma_address = drm_calloc_large(ttm->ttm.num_pages,
+					    sizeof(*ttm->dma_address));
 }
 
 #ifdef CONFIG_X86
@@ -173,7 +170,6 @@ void ttm_tt_destroy(struct ttm_tt *ttm)
 
 	if (likely(ttm->pages != NULL)) {
 		ttm->bdev->driver->ttm_tt_unpopulate(ttm);
-		ttm_tt_free_page_directory(ttm);
 	}
 
 	if (!(ttm->page_flags & TTM_PAGE_FLAG_PERSISTENT_SWAP) &&
@@ -196,9 +192,8 @@ int ttm_tt_init(struct ttm_tt *ttm, struct ttm_bo_device *bdev,
 	ttm->dummy_read_page = dummy_read_page;
 	ttm->state = tt_unpopulated;
 
-	INIT_LIST_HEAD(&ttm->alloc_list);
 	ttm_tt_alloc_page_directory(ttm);
-	if (!ttm->pages || !ttm->dma_address) {
+	if (!ttm->pages) {
 		ttm_tt_destroy(ttm);
 		printk(KERN_ERR TTM_PFX "Failed allocating page table\n");
 		return -ENOMEM;
@@ -207,6 +202,49 @@ int ttm_tt_init(struct ttm_tt *ttm, struct ttm_bo_device *bdev,
 }
 EXPORT_SYMBOL(ttm_tt_init);
 
+void ttm_tt_fini(struct ttm_tt *ttm)
+{
+	drm_free_large(ttm->pages);
+	ttm->pages = NULL;
+}
+EXPORT_SYMBOL(ttm_tt_fini);
+
+int ttm_dma_tt_init(struct ttm_dma_tt *ttm_dma, struct ttm_bo_device *bdev,
+		unsigned long size, uint32_t page_flags,
+		struct page *dummy_read_page)
+{
+	struct ttm_tt *ttm = &ttm_dma->ttm;
+
+	ttm->bdev = bdev;
+	ttm->glob = bdev->glob;
+	ttm->num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
+	ttm->caching_state = tt_cached;
+	ttm->page_flags = page_flags;
+	ttm->dummy_read_page = dummy_read_page;
+	ttm->state = tt_unpopulated;
+
+	INIT_LIST_HEAD(&ttm_dma->pages_list);
+	ttm_dma_tt_alloc_page_directory(ttm_dma);
+	if (!ttm->pages || !ttm_dma->dma_address) {
+		ttm_tt_destroy(ttm);
+		printk(KERN_ERR TTM_PFX "Failed allocating page table\n");
+		return -ENOMEM;
+	}
+	return 0;
+}
+EXPORT_SYMBOL(ttm_dma_tt_init);
+
+void ttm_dma_tt_fini(struct ttm_dma_tt *ttm_dma)
+{
+	struct ttm_tt *ttm = &ttm_dma->ttm;
+
+	drm_free_large(ttm->pages);
+	ttm->pages = NULL;
+	drm_free_large(ttm_dma->dma_address);
+	ttm_dma->dma_address = NULL;
+}
+EXPORT_SYMBOL(ttm_dma_tt_fini);
+
 void ttm_tt_unbind(struct ttm_tt *ttm)
 {
 	int ret;