drm/ttm: merge ttm_backend and ttm_tt V5

ttm_backend will only exist with a ttm_tt, and ttm_tt
will only be of interest when bound to a backend. Merge them
to avoid code and data duplication.

V2 Rebase on top of memory accounting overhaul
V3 Rebase on top of more memory accounting changes
V4 Rebase on top of no memory account changes (where/when is my
   delorean when i need it ?)
V5 make sure ttm is unbound before destroying, change commit
   message on suggestion from Tormod Volden

Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>

3 files changed, 51 insertions, 105 deletions

diff --git a/drivers/gpu/drm/ttm/ttm_agp_backend.c b/drivers/gpu/drm/ttm/ttm_agp_backend.c
index 1c4a72f681c1..14ebd3650aa9 100644
--- a/drivers/gpu/drm/ttm/ttm_agp_backend.c
+++ b/drivers/gpu/drm/ttm/ttm_agp_backend.c
@@ -40,45 +40,33 @@
 #include <asm/agp.h>
 
 struct ttm_agp_backend {
-	struct ttm_backend backend;
+	struct ttm_tt ttm;
 	struct agp_memory *mem;
 	struct agp_bridge_data *bridge;
 };
 
-static int ttm_agp_populate(struct ttm_backend *backend,
-			    unsigned long num_pages, struct page **pages,
-			    struct page *dummy_read_page,
-			    dma_addr_t *dma_addrs)
+static int ttm_agp_bind(struct ttm_tt *ttm, struct ttm_mem_reg *bo_mem)
 {
-	struct ttm_agp_backend *agp_be =
-	    container_of(backend, struct ttm_agp_backend, backend);
-	struct page **cur_page, **last_page = pages + num_pages;
+	struct ttm_agp_backend *agp_be = container_of(ttm, struct ttm_agp_backend, ttm);
+	struct drm_mm_node *node = bo_mem->mm_node;
 	struct agp_memory *mem;
+	int ret, cached = (bo_mem->placement & TTM_PL_FLAG_CACHED);
+	unsigned i;
 
-	mem = agp_allocate_memory(agp_be->bridge, num_pages, AGP_USER_MEMORY);
+	mem = agp_allocate_memory(agp_be->bridge, ttm->num_pages, AGP_USER_MEMORY);
 	if (unlikely(mem == NULL))
 		return -ENOMEM;
 
 	mem->page_count = 0;
-	for (cur_page = pages; cur_page < last_page; ++cur_page) {
-		struct page *page = *cur_page;
+	for (i = 0; i < ttm->num_pages; i++) {
+		struct page *page = ttm->pages[i];
+
 		if (!page)
-			page = dummy_read_page;
+			page = ttm->dummy_read_page;
 
 		mem->pages[mem->page_count++] = page;
 	}
 	agp_be->mem = mem;
-	return 0;
-}
-
-static int ttm_agp_bind(struct ttm_backend *backend, struct ttm_mem_reg *bo_mem)
-{
-	struct ttm_agp_backend *agp_be =
-	    container_of(backend, struct ttm_agp_backend, backend);
-	struct drm_mm_node *node = bo_mem->mm_node;
-	struct agp_memory *mem = agp_be->mem;
-	int cached = (bo_mem->placement & TTM_PL_FLAG_CACHED);
-	int ret;
 
 	mem->is_flushed = 1;
 	mem->type = (cached) ? AGP_USER_CACHED_MEMORY : AGP_USER_MEMORY;
@@ -90,50 +78,38 @@ static int ttm_agp_bind(struct ttm_backend *backend, struct ttm_mem_reg *bo_mem)
 	return ret;
 }
 
-static int ttm_agp_unbind(struct ttm_backend *backend)
+static int ttm_agp_unbind(struct ttm_tt *ttm)
 {
-	struct ttm_agp_backend *agp_be =
-	    container_of(backend, struct ttm_agp_backend, backend);
-
-	if (agp_be->mem->is_bound)
-		return agp_unbind_memory(agp_be->mem);
-	else
-		return 0;
-}
+	struct ttm_agp_backend *agp_be = container_of(ttm, struct ttm_agp_backend, ttm);
 
-static void ttm_agp_clear(struct ttm_backend *backend)
-{
-	struct ttm_agp_backend *agp_be =
-	    container_of(backend, struct ttm_agp_backend, backend);
-	struct agp_memory *mem = agp_be->mem;
-
-	if (mem) {
-		ttm_agp_unbind(backend);
-		agp_free_memory(mem);
+	if (agp_be->mem) {
+		if (agp_be->mem->is_bound)
+			return agp_unbind_memory(agp_be->mem);
+		agp_free_memory(agp_be->mem);
+		agp_be->mem = NULL;
 	}
-	agp_be->mem = NULL;
+	return 0;
 }
 
-static void ttm_agp_destroy(struct ttm_backend *backend)
+static void ttm_agp_destroy(struct ttm_tt *ttm)
 {
-	struct ttm_agp_backend *agp_be =
-	    container_of(backend, struct ttm_agp_backend, backend);
+	struct ttm_agp_backend *agp_be = container_of(ttm, struct ttm_agp_backend, ttm);
 
 	if (agp_be->mem)
-		ttm_agp_clear(backend);
+		ttm_agp_unbind(ttm);
 	kfree(agp_be);
 }
 
 static struct ttm_backend_func ttm_agp_func = {
-	.populate = ttm_agp_populate,
-	.clear = ttm_agp_clear,
 	.bind = ttm_agp_bind,
 	.unbind = ttm_agp_unbind,
 	.destroy = ttm_agp_destroy,
 };
 
-struct ttm_backend *ttm_agp_backend_init(struct ttm_bo_device *bdev,
-					 struct agp_bridge_data *bridge)
+struct ttm_tt *ttm_agp_tt_create(struct ttm_bo_device *bdev,
+				 struct agp_bridge_data *bridge,
+				 unsigned long size, uint32_t page_flags,
+				 struct page *dummy_read_page)
 {
 	struct ttm_agp_backend *agp_be;
 
@@ -143,10 +119,14 @@ struct ttm_backend *ttm_agp_backend_init(struct ttm_bo_device *bdev,
 
 	agp_be->mem = NULL;
 	agp_be->bridge = bridge;
-	agp_be->backend.func = &ttm_agp_func;
-	agp_be->backend.bdev = bdev;
-	return &agp_be->backend;
+	agp_be->ttm.func = &ttm_agp_func;
+
+	if (ttm_tt_init(&agp_be->ttm, bdev, size, page_flags, dummy_read_page)) {
+		return NULL;
+	}
+
+	return &agp_be->ttm;
 }
-EXPORT_SYMBOL(ttm_agp_backend_init);
+EXPORT_SYMBOL(ttm_agp_tt_create);
 
 #endif
diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c
index 4bde3356ecb2..cb7352712750 100644
--- a/drivers/gpu/drm/ttm/ttm_bo.c
+++ b/drivers/gpu/drm/ttm/ttm_bo.c
@@ -337,8 +337,8 @@ static int ttm_bo_add_ttm(struct ttm_buffer_object *bo, bool zero_alloc)
 		if (zero_alloc)
 			page_flags |= TTM_PAGE_FLAG_ZERO_ALLOC;
 	case ttm_bo_type_kernel:
-		bo->ttm = ttm_tt_create(bdev, bo->num_pages << PAGE_SHIFT,
-					page_flags, glob->dummy_read_page);
+		bo->ttm = bdev->driver->ttm_tt_create(bdev, bo->num_pages << PAGE_SHIFT,
+						      page_flags, glob->dummy_read_page);
 		if (unlikely(bo->ttm == NULL))
 			ret = -ENOMEM;
 		break;
@@ -1437,10 +1437,7 @@ int ttm_bo_global_init(struct drm_global_reference *ref)
 		goto out_no_shrink;
 	}
 
-	glob->ttm_bo_extra_size =
-		ttm_round_pot(sizeof(struct ttm_tt)) +
-		ttm_round_pot(sizeof(struct ttm_backend));
-
+	glob->ttm_bo_extra_size = ttm_round_pot(sizeof(struct ttm_tt));
 	glob->ttm_bo_size = glob->ttm_bo_extra_size +
 		ttm_round_pot(sizeof(struct ttm_buffer_object));
 
diff --git a/drivers/gpu/drm/ttm/ttm_tt.c b/drivers/gpu/drm/ttm/ttm_tt.c
index 6e079dedfc4f..fbc90dce1de8 100644
--- a/drivers/gpu/drm/ttm/ttm_tt.c
+++ b/drivers/gpu/drm/ttm/ttm_tt.c
@@ -105,7 +105,6 @@ int ttm_tt_populate(struct ttm_tt *ttm)
 {
 	struct page *page;
 	unsigned long i;
-	struct ttm_backend *be;
 	int ret;
 
 	if (ttm->state != tt_unpopulated)
@@ -117,16 +116,11 @@ int ttm_tt_populate(struct ttm_tt *ttm)
 			return ret;
 	}
 
-	be = ttm->be;
-
 	for (i = 0; i < ttm->num_pages; ++i) {
 		page = __ttm_tt_get_page(ttm, i);
 		if (!page)
 			return -ENOMEM;
 	}
-
-	be->func->populate(be, ttm->num_pages, ttm->pages,
-			   ttm->dummy_read_page, ttm->dma_address);
 	ttm->state = tt_unbound;
 	return 0;
 }
@@ -235,11 +229,8 @@ EXPORT_SYMBOL(ttm_tt_set_placement_caching);
 
 static void ttm_tt_free_alloced_pages(struct ttm_tt *ttm)
 {
-	struct ttm_backend *be = ttm->be;
 	unsigned i;
 
-	if (be)
-		be->func->clear(be);
 	for (i = 0; i < ttm->num_pages; ++i) {
 		if (ttm->pages[i]) {
 			ttm_mem_global_free_page(ttm->glob->mem_glob,
@@ -253,20 +244,15 @@ static void ttm_tt_free_alloced_pages(struct ttm_tt *ttm)
 
 void ttm_tt_destroy(struct ttm_tt *ttm)
 {
-	struct ttm_backend *be;
-
 	if (unlikely(ttm == NULL))
 		return;
 
-	be = ttm->be;
-	if (likely(be != NULL)) {
-		be->func->destroy(be);
-		ttm->be = NULL;
+	if (ttm->state == tt_bound) {
+		ttm_tt_unbind(ttm);
 	}
 
 	if (likely(ttm->pages != NULL)) {
 		ttm_tt_free_alloced_pages(ttm);
-
 		ttm_tt_free_page_directory(ttm);
 	}
 
@@ -274,52 +260,38 @@ void ttm_tt_destroy(struct ttm_tt *ttm)
 	    ttm->swap_storage)
 		fput(ttm->swap_storage);
 
-	kfree(ttm);
+	ttm->swap_storage = NULL;
+	ttm->func->destroy(ttm);
 }
 
-struct ttm_tt *ttm_tt_create(struct ttm_bo_device *bdev, unsigned long size,
-			     uint32_t page_flags, struct page *dummy_read_page)
+int ttm_tt_init(struct ttm_tt *ttm, struct ttm_bo_device *bdev,
+		unsigned long size, uint32_t page_flags,
+		struct page *dummy_read_page)
 {
-	struct ttm_bo_driver *bo_driver = bdev->driver;
-	struct ttm_tt *ttm;
-
-	if (!bo_driver)
-		return NULL;
-
-	ttm = kzalloc(sizeof(*ttm), GFP_KERNEL);
-	if (!ttm)
-		return NULL;
-
+	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;
 
 	ttm_tt_alloc_page_directory(ttm);
 	if (!ttm->pages || !ttm->dma_address) {
 		ttm_tt_destroy(ttm);
 		printk(KERN_ERR TTM_PFX "Failed allocating page table\n");
-		return NULL;
-	}
-	ttm->be = bo_driver->create_ttm_backend_entry(bdev);
-	if (!ttm->be) {
-		ttm_tt_destroy(ttm);
-		printk(KERN_ERR TTM_PFX "Failed creating ttm backend entry\n");
-		return NULL;
+		return -ENOMEM;
 	}
-	ttm->state = tt_unpopulated;
-	return ttm;
+	return 0;
 }
+EXPORT_SYMBOL(ttm_tt_init);
 
 void ttm_tt_unbind(struct ttm_tt *ttm)
 {
 	int ret;
-	struct ttm_backend *be = ttm->be;
 
 	if (ttm->state == tt_bound) {
-		ret = be->func->unbind(be);
+		ret = ttm->func->unbind(ttm);
 		BUG_ON(ret);
 		ttm->state = tt_unbound;
 	}
@@ -328,7 +300,6 @@ void ttm_tt_unbind(struct ttm_tt *ttm)
 int ttm_tt_bind(struct ttm_tt *ttm, struct ttm_mem_reg *bo_mem)
 {
 	int ret = 0;
-	struct ttm_backend *be;
 
 	if (!ttm)
 		return -EINVAL;
@@ -336,13 +307,11 @@ int ttm_tt_bind(struct ttm_tt *ttm, struct ttm_mem_reg *bo_mem)
 	if (ttm->state == tt_bound)
 		return 0;
 
-	be = ttm->be;
-
 	ret = ttm_tt_populate(ttm);
 	if (ret)
 		return ret;
 
-	ret = be->func->bind(be, bo_mem);
+	ret = ttm->func->bind(ttm, bo_mem);
 	if (unlikely(ret != 0))
 		return ret;