drivers/gpu/drm/ast/ast_ttm.c - kernel/common - Git at Google

 /*
  * Copyright 2012 Red Hat Inc.
  *
  * Permission is hereby granted, free of charge, to any person obtaining a
  * copy of this software and associated documentation files (the
  * "Software"), to deal in the Software without restriction, including
  * without limitation the rights to use, copy, modify, merge, publish,
  * distribute, sub license, and/or sell copies of the Software, and to
  * permit persons to whom the Software is furnished to do so, subject to
  * the following conditions:
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
  * USE OR OTHER DEALINGS IN THE SOFTWARE.
  *
  * The above copyright notice and this permission notice (including the
  * next paragraph) shall be included in all copies or substantial portions
  * of the Software.
  *
  */
 /*
  * Authors: Dave Airlie <[email protected]>
  */
 #include <drm/drmP.h>
 #include <drm/ttm/ttm_page_alloc.h>

 #include "ast_drv.h"

 static inline struct ast_private *
 ast_bdev(struct ttm_bo_device *bd)
 {
 	return container_of(bd, struct ast_private, ttm.bdev);
 }

 static void ast_bo_ttm_destroy(struct ttm_buffer_object *tbo)
 {
 	struct ast_bo *bo;

 	bo = container_of(tbo, struct ast_bo, bo);

 	drm_gem_object_release(&bo->gem);
 	kfree(bo);
 }

 static bool ast_ttm_bo_is_ast_bo(struct ttm_buffer_object *bo)
 {
 	if (bo->destroy == &ast_bo_ttm_destroy)
 		return true;
 	return false;
 }

 static int
 ast_bo_init_mem_type(struct ttm_bo_device *bdev, uint32_t type,
 		     struct ttm_mem_type_manager *man)
 {
 	switch (type) {
 	case TTM_PL_SYSTEM:
 		man->flags = TTM_MEMTYPE_FLAG_MAPPABLE;
 		man->available_caching = TTM_PL_MASK_CACHING;
 		man->default_caching = TTM_PL_FLAG_CACHED;
 		break;
 	case TTM_PL_VRAM:
 		man->func = &ttm_bo_manager_func;
 		man->flags = TTM_MEMTYPE_FLAG_FIXED |
 			TTM_MEMTYPE_FLAG_MAPPABLE;
 		man->available_caching = TTM_PL_FLAG_UNCACHED |
 			TTM_PL_FLAG_WC;
 		man->default_caching = TTM_PL_FLAG_WC;
 		break;
 	default:
 		DRM_ERROR("Unsupported memory type %u\n", (unsigned)type);
 		return -EINVAL;
 	}
 	return 0;
 }

 static void
 ast_bo_evict_flags(struct ttm_buffer_object *bo, struct ttm_placement *pl)
 {
 	struct ast_bo *astbo = ast_bo(bo);

 	if (!ast_ttm_bo_is_ast_bo(bo))
 		return;

 	ast_ttm_placement(astbo, TTM_PL_FLAG_SYSTEM);
 	*pl = astbo->placement;
 }

 static int ast_bo_verify_access(struct ttm_buffer_object *bo, struct file *filp)
 {
 	struct ast_bo *astbo = ast_bo(bo);

 	return drm_vma_node_verify_access(&astbo->gem.vma_node,
 					  filp->private_data);
 }

 static int ast_ttm_io_mem_reserve(struct ttm_bo_device *bdev,
 				  struct ttm_mem_reg *mem)
 {
 	struct ttm_mem_type_manager *man = &bdev->man[mem->mem_type];
 	struct ast_private *ast = ast_bdev(bdev);

 	mem->bus.addr = NULL;
 	mem->bus.offset = 0;
 	mem->bus.size = mem->num_pages << PAGE_SHIFT;
 	mem->bus.base = 0;
 	mem->bus.is_iomem = false;
 	if (!(man->flags & TTM_MEMTYPE_FLAG_MAPPABLE))
 		return -EINVAL;
 	switch (mem->mem_type) {
 	case TTM_PL_SYSTEM:
 		/* system memory */
 		return 0;
 	case TTM_PL_VRAM:
 		mem->bus.offset = mem->start << PAGE_SHIFT;
 		mem->bus.base = pci_resource_start(ast->dev->pdev, 0);
 		mem->bus.is_iomem = true;
 		break;
 	default:
 		return -EINVAL;
 		break;
 	}
 	return 0;
 }

 static void ast_ttm_io_mem_free(struct ttm_bo_device *bdev, struct ttm_mem_reg *mem)
 {
 }

 static void ast_ttm_backend_destroy(struct ttm_tt *tt)
 {
 	ttm_tt_fini(tt);
 	kfree(tt);
 }

 static struct ttm_backend_func ast_tt_backend_func = {
 	.destroy = &ast_ttm_backend_destroy,
 };


 static struct ttm_tt *ast_ttm_tt_create(struct ttm_buffer_object *bo,
 					uint32_t page_flags)
 {
 	struct ttm_tt *tt;

 	tt = kzalloc(sizeof(struct ttm_tt), GFP_KERNEL);
 	if (tt == NULL)
 		return NULL;
 	tt->func = &ast_tt_backend_func;
 	if (ttm_tt_init(tt, bo, page_flags)) {
 		kfree(tt);
 		return NULL;
 	}
 	return tt;
 }

 struct ttm_bo_driver ast_bo_driver = {
 	.ttm_tt_create = ast_ttm_tt_create,
 	.init_mem_type = ast_bo_init_mem_type,
 	.eviction_valuable = ttm_bo_eviction_valuable,
 	.evict_flags = ast_bo_evict_flags,
 	.move = NULL,
 	.verify_access = ast_bo_verify_access,
 	.io_mem_reserve = &ast_ttm_io_mem_reserve,
 	.io_mem_free = &ast_ttm_io_mem_free,
 };

 int ast_mm_init(struct ast_private *ast)
 {
 	int ret;
 	struct drm_device *dev = ast->dev;
 	struct ttm_bo_device *bdev = &ast->ttm.bdev;

 	ret = ttm_bo_device_init(&ast->ttm.bdev,
 				 &ast_bo_driver,
 				 dev->anon_inode->i_mapping,
 				 true);
 	if (ret) {
 		DRM_ERROR("Error initialising bo driver; %d\n", ret);
 		return ret;
 	}

 	ret = ttm_bo_init_mm(bdev, TTM_PL_VRAM,
 			     ast->vram_size >> PAGE_SHIFT);
 	if (ret) {
 		DRM_ERROR("Failed ttm VRAM init: %d\n", ret);
 		return ret;
 	}

 	arch_io_reserve_memtype_wc(pci_resource_start(dev->pdev, 0),
 				   pci_resource_len(dev->pdev, 0));
 	ast->fb_mtrr = arch_phys_wc_add(pci_resource_start(dev->pdev, 0),
 					pci_resource_len(dev->pdev, 0));

 	return 0;
 }

 void ast_mm_fini(struct ast_private *ast)
 {
 	struct drm_device *dev = ast->dev;

 	ttm_bo_device_release(&ast->ttm.bdev);

 	arch_phys_wc_del(ast->fb_mtrr);
 	arch_io_free_memtype_wc(pci_resource_start(dev->pdev, 0),
 				pci_resource_len(dev->pdev, 0));
 }

 void ast_ttm_placement(struct ast_bo *bo, int domain)
 {
 	u32 c = 0;
 	unsigned i;

 	bo->placement.placement = bo->placements;
 	bo->placement.busy_placement = bo->placements;
 	if (domain & TTM_PL_FLAG_VRAM)
 		bo->placements[c++].flags = TTM_PL_FLAG_WC | TTM_PL_FLAG_UNCACHED | TTM_PL_FLAG_VRAM;
 	if (domain & TTM_PL_FLAG_SYSTEM)
 		bo->placements[c++].flags = TTM_PL_FLAG_CACHED | TTM_PL_FLAG_SYSTEM;
 	if (!c)
 		bo->placements[c++].flags = TTM_PL_FLAG_CACHED | TTM_PL_FLAG_SYSTEM;
 	bo->placement.num_placement = c;
 	bo->placement.num_busy_placement = c;
 	for (i = 0; i < c; ++i) {
 		bo->placements[i].fpfn = 0;
 		bo->placements[i].lpfn = 0;
 	}
 }

 int ast_bo_create(struct drm_device *dev, int size, int align,
 		  uint32_t flags, struct ast_bo **pastbo)
 {
 	struct ast_private *ast = dev->dev_private;
 	struct ast_bo *astbo;
 	size_t acc_size;
 	int ret;

 	astbo = kzalloc(sizeof(struct ast_bo), GFP_KERNEL);
 	if (!astbo)
 		return -ENOMEM;

 	ret = drm_gem_object_init(dev, &astbo->gem, size);
 	if (ret)
 		goto error;

 	astbo->bo.bdev = &ast->ttm.bdev;

 	ast_ttm_placement(astbo, TTM_PL_FLAG_VRAM | TTM_PL_FLAG_SYSTEM);

 	acc_size = ttm_bo_dma_acc_size(&ast->ttm.bdev, size,
 				       sizeof(struct ast_bo));

 	ret = ttm_bo_init(&ast->ttm.bdev, &astbo->bo, size,
 			  ttm_bo_type_device, &astbo->placement,
 			  align >> PAGE_SHIFT, false, acc_size,
 			  NULL, NULL, ast_bo_ttm_destroy);
 	if (ret)
 		goto error;

 	*pastbo = astbo;
 	return 0;
 error:
 	kfree(astbo);
 	return ret;
 }

 static inline u64 ast_bo_gpu_offset(struct ast_bo *bo)
 {
 	return bo->bo.offset;
 }

 int ast_bo_pin(struct ast_bo *bo, u32 pl_flag, u64 *gpu_addr)
 {
 	struct ttm_operation_ctx ctx = { false, false };
 	int i, ret;

 	if (bo->pin_count) {
 		bo->pin_count++;
 		if (gpu_addr)
 			*gpu_addr = ast_bo_gpu_offset(bo);
 	}

 	ast_ttm_placement(bo, pl_flag);
 	for (i = 0; i < bo->placement.num_placement; i++)
 		bo->placements[i].flags |= TTM_PL_FLAG_NO_EVICT;
 	ret = ttm_bo_validate(&bo->bo, &bo->placement, &ctx);
 	if (ret)
 		return ret;

 	bo->pin_count = 1;
 	if (gpu_addr)
 		*gpu_addr = ast_bo_gpu_offset(bo);
 	return 0;
 }

 int ast_bo_unpin(struct ast_bo *bo)
 {
 	struct ttm_operation_ctx ctx = { false, false };
 	int i;
 	if (!bo->pin_count) {
 		DRM_ERROR("unpin bad %p\n", bo);
 		return 0;
 	}
 	bo->pin_count--;
 	if (bo->pin_count)
 		return 0;

 	for (i = 0; i < bo->placement.num_placement ; i++)
 		bo->placements[i].flags &= ~TTM_PL_FLAG_NO_EVICT;
 	return ttm_bo_validate(&bo->bo, &bo->placement, &ctx);
 }

 int ast_bo_push_sysram(struct ast_bo *bo)
 {
 	struct ttm_operation_ctx ctx = { false, false };
 	int i, ret;
 	if (!bo->pin_count) {
 		DRM_ERROR("unpin bad %p\n", bo);
 		return 0;
 	}
 	bo->pin_count--;
 	if (bo->pin_count)
 		return 0;

 	if (bo->kmap.virtual)
 		ttm_bo_kunmap(&bo->kmap);

 	ast_ttm_placement(bo, TTM_PL_FLAG_SYSTEM);
 	for (i = 0; i < bo->placement.num_placement ; i++)
 		bo->placements[i].flags |= TTM_PL_FLAG_NO_EVICT;

 	ret = ttm_bo_validate(&bo->bo, &bo->placement, &ctx);
 	if (ret) {
 		DRM_ERROR("pushing to VRAM failed\n");
 		return ret;
 	}
 	return 0;
 }

 int ast_mmap(struct file *filp, struct vm_area_struct *vma)
 {
 	struct drm_file *file_priv = filp->private_data;
 	struct ast_private *ast = file_priv->minor->dev->dev_private;

 	return ttm_bo_mmap(filp, vma, &ast->ttm.bdev);
 }
	/*
	* Copyright 2012 Red Hat Inc.
	*
	* Permission is hereby granted, free of charge, to any person obtaining a
	* copy of this software and associated documentation files (the
	* "Software"), to deal in the Software without restriction, including
	* without limitation the rights to use, copy, modify, merge, publish,
	* distribute, sub license, and/or sell copies of the Software, and to
	* permit persons to whom the Software is furnished to do so, subject to
	* the following conditions:
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	* FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
	* THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
	* DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
	* OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
	* USE OR OTHER DEALINGS IN THE SOFTWARE.
	*
	* The above copyright notice and this permission notice (including the
	* next paragraph) shall be included in all copies or substantial portions
	* of the Software.
	*
	*/
	/*
	* Authors: Dave Airlie <[email protected]>
	*/
	#include <drm/drmP.h>
	#include <drm/ttm/ttm_page_alloc.h>

	#include "ast_drv.h"

	static inline struct ast_private *
	ast_bdev(struct ttm_bo_device *bd)
	{
	return container_of(bd, struct ast_private, ttm.bdev);
	}

	static void ast_bo_ttm_destroy(struct ttm_buffer_object *tbo)
	{
	struct ast_bo *bo;

	bo = container_of(tbo, struct ast_bo, bo);

	drm_gem_object_release(&bo->gem);
	kfree(bo);
	}

	static bool ast_ttm_bo_is_ast_bo(struct ttm_buffer_object *bo)
	{
	if (bo->destroy == &ast_bo_ttm_destroy)
	return true;
	return false;
	}

	static int
	ast_bo_init_mem_type(struct ttm_bo_device *bdev, uint32_t type,
	struct ttm_mem_type_manager *man)
	{
	switch (type) {
	case TTM_PL_SYSTEM:
	man->flags = TTM_MEMTYPE_FLAG_MAPPABLE;
	man->available_caching = TTM_PL_MASK_CACHING;
	man->default_caching = TTM_PL_FLAG_CACHED;
	break;
	case TTM_PL_VRAM:
	man->func = &ttm_bo_manager_func;
	man->flags = TTM_MEMTYPE_FLAG_FIXED \|
	TTM_MEMTYPE_FLAG_MAPPABLE;
	man->available_caching = TTM_PL_FLAG_UNCACHED \|
	TTM_PL_FLAG_WC;
	man->default_caching = TTM_PL_FLAG_WC;
	break;
	default:
	DRM_ERROR("Unsupported memory type %u\n", (unsigned)type);
	return -EINVAL;
	}
	return 0;
	}

	static void
	ast_bo_evict_flags(struct ttm_buffer_object bo, struct ttm_placement pl)
	{
	struct ast_bo *astbo = ast_bo(bo);

	if (!ast_ttm_bo_is_ast_bo(bo))
	return;

	ast_ttm_placement(astbo, TTM_PL_FLAG_SYSTEM);
	*pl = astbo->placement;
	}

	static int ast_bo_verify_access(struct ttm_buffer_object bo, struct file filp)
	{
	struct ast_bo *astbo = ast_bo(bo);

	return drm_vma_node_verify_access(&astbo->gem.vma_node,
	filp->private_data);
	}

	static int ast_ttm_io_mem_reserve(struct ttm_bo_device *bdev,
	struct ttm_mem_reg *mem)
	{
	struct ttm_mem_type_manager *man = &bdev->man[mem->mem_type];
	struct ast_private *ast = ast_bdev(bdev);

	mem->bus.addr = NULL;
	mem->bus.offset = 0;
	mem->bus.size = mem->num_pages << PAGE_SHIFT;
	mem->bus.base = 0;
	mem->bus.is_iomem = false;
	if (!(man->flags & TTM_MEMTYPE_FLAG_MAPPABLE))
	return -EINVAL;
	switch (mem->mem_type) {
	case TTM_PL_SYSTEM:
	/* system memory */
	return 0;
	case TTM_PL_VRAM:
	mem->bus.offset = mem->start << PAGE_SHIFT;
	mem->bus.base = pci_resource_start(ast->dev->pdev, 0);
	mem->bus.is_iomem = true;
	break;
	default:
	return -EINVAL;
	break;
	}
	return 0;
	}

	static void ast_ttm_io_mem_free(struct ttm_bo_device bdev, struct ttm_mem_reg mem)
	{
	}

	static void ast_ttm_backend_destroy(struct ttm_tt *tt)
	{
	ttm_tt_fini(tt);
	kfree(tt);
	}

	static struct ttm_backend_func ast_tt_backend_func = {
	.destroy = &ast_ttm_backend_destroy,
	};


	static struct ttm_tt ast_ttm_tt_create(struct ttm_buffer_object bo,
	uint32_t page_flags)
	{
	struct ttm_tt *tt;

	tt = kzalloc(sizeof(struct ttm_tt), GFP_KERNEL);
	if (tt == NULL)
	return NULL;
	tt->func = &ast_tt_backend_func;
	if (ttm_tt_init(tt, bo, page_flags)) {
	kfree(tt);
	return NULL;
	}
	return tt;
	}

	struct ttm_bo_driver ast_bo_driver = {
	.ttm_tt_create = ast_ttm_tt_create,
	.init_mem_type = ast_bo_init_mem_type,
	.eviction_valuable = ttm_bo_eviction_valuable,
	.evict_flags = ast_bo_evict_flags,
	.move = NULL,
	.verify_access = ast_bo_verify_access,
	.io_mem_reserve = &ast_ttm_io_mem_reserve,
	.io_mem_free = &ast_ttm_io_mem_free,
	};

	int ast_mm_init(struct ast_private *ast)
	{
	int ret;
	struct drm_device *dev = ast->dev;
	struct ttm_bo_device *bdev = &ast->ttm.bdev;

	ret = ttm_bo_device_init(&ast->ttm.bdev,
	&ast_bo_driver,
	dev->anon_inode->i_mapping,
	true);
	if (ret) {
	DRM_ERROR("Error initialising bo driver; %d\n", ret);
	return ret;
	}

	ret = ttm_bo_init_mm(bdev, TTM_PL_VRAM,
	ast->vram_size >> PAGE_SHIFT);
	if (ret) {
	DRM_ERROR("Failed ttm VRAM init: %d\n", ret);
	return ret;
	}

	arch_io_reserve_memtype_wc(pci_resource_start(dev->pdev, 0),
	pci_resource_len(dev->pdev, 0));
	ast->fb_mtrr = arch_phys_wc_add(pci_resource_start(dev->pdev, 0),
	pci_resource_len(dev->pdev, 0));

	return 0;
	}

	void ast_mm_fini(struct ast_private *ast)
	{
	struct drm_device *dev = ast->dev;

	ttm_bo_device_release(&ast->ttm.bdev);

	arch_phys_wc_del(ast->fb_mtrr);
	arch_io_free_memtype_wc(pci_resource_start(dev->pdev, 0),
	pci_resource_len(dev->pdev, 0));
	}

	void ast_ttm_placement(struct ast_bo *bo, int domain)
	{
	u32 c = 0;
	unsigned i;

	bo->placement.placement = bo->placements;
	bo->placement.busy_placement = bo->placements;
	if (domain & TTM_PL_FLAG_VRAM)
	bo->placements[c++].flags = TTM_PL_FLAG_WC \| TTM_PL_FLAG_UNCACHED \| TTM_PL_FLAG_VRAM;
	if (domain & TTM_PL_FLAG_SYSTEM)
	bo->placements[c++].flags = TTM_PL_FLAG_CACHED \| TTM_PL_FLAG_SYSTEM;
	if (!c)
	bo->placements[c++].flags = TTM_PL_FLAG_CACHED \| TTM_PL_FLAG_SYSTEM;
	bo->placement.num_placement = c;
	bo->placement.num_busy_placement = c;
	for (i = 0; i < c; ++i) {
	bo->placements[i].fpfn = 0;
	bo->placements[i].lpfn = 0;
	}
	}

	int ast_bo_create(struct drm_device *dev, int size, int align,
	uint32_t flags, struct ast_bo **pastbo)
	{
	struct ast_private *ast = dev->dev_private;
	struct ast_bo *astbo;
	size_t acc_size;
	int ret;

	astbo = kzalloc(sizeof(struct ast_bo), GFP_KERNEL);
	if (!astbo)
	return -ENOMEM;

	ret = drm_gem_object_init(dev, &astbo->gem, size);
	if (ret)
	goto error;

	astbo->bo.bdev = &ast->ttm.bdev;

	ast_ttm_placement(astbo, TTM_PL_FLAG_VRAM \| TTM_PL_FLAG_SYSTEM);

	acc_size = ttm_bo_dma_acc_size(&ast->ttm.bdev, size,
	sizeof(struct ast_bo));

	ret = ttm_bo_init(&ast->ttm.bdev, &astbo->bo, size,
	ttm_bo_type_device, &astbo->placement,
	align >> PAGE_SHIFT, false, acc_size,
	NULL, NULL, ast_bo_ttm_destroy);
	if (ret)
	goto error;

	*pastbo = astbo;
	return 0;
	error:
	kfree(astbo);
	return ret;
	}

	static inline u64 ast_bo_gpu_offset(struct ast_bo *bo)
	{
	return bo->bo.offset;
	}

	int ast_bo_pin(struct ast_bo bo, u32 pl_flag, u64 gpu_addr)
	{
	struct ttm_operation_ctx ctx = { false, false };
	int i, ret;

	if (bo->pin_count) {
	bo->pin_count++;
	if (gpu_addr)
	*gpu_addr = ast_bo_gpu_offset(bo);
	}

	ast_ttm_placement(bo, pl_flag);
	for (i = 0; i < bo->placement.num_placement; i++)
	bo->placements[i].flags \|= TTM_PL_FLAG_NO_EVICT;
	ret = ttm_bo_validate(&bo->bo, &bo->placement, &ctx);
	if (ret)
	return ret;

	bo->pin_count = 1;
	if (gpu_addr)
	*gpu_addr = ast_bo_gpu_offset(bo);
	return 0;
	}

	int ast_bo_unpin(struct ast_bo *bo)
	{
	struct ttm_operation_ctx ctx = { false, false };
	int i;
	if (!bo->pin_count) {
	DRM_ERROR("unpin bad %p\n", bo);
	return 0;
	}
	bo->pin_count--;
	if (bo->pin_count)
	return 0;

	for (i = 0; i < bo->placement.num_placement ; i++)
	bo->placements[i].flags &= ~TTM_PL_FLAG_NO_EVICT;
	return ttm_bo_validate(&bo->bo, &bo->placement, &ctx);
	}

	int ast_bo_push_sysram(struct ast_bo *bo)
	{
	struct ttm_operation_ctx ctx = { false, false };
	int i, ret;
	if (!bo->pin_count) {
	DRM_ERROR("unpin bad %p\n", bo);
	return 0;
	}
	bo->pin_count--;
	if (bo->pin_count)
	return 0;

	if (bo->kmap.virtual)
	ttm_bo_kunmap(&bo->kmap);

	ast_ttm_placement(bo, TTM_PL_FLAG_SYSTEM);
	for (i = 0; i < bo->placement.num_placement ; i++)
	bo->placements[i].flags \|= TTM_PL_FLAG_NO_EVICT;

	ret = ttm_bo_validate(&bo->bo, &bo->placement, &ctx);
	if (ret) {
	DRM_ERROR("pushing to VRAM failed\n");
	return ret;
	}
	return 0;
	}

	int ast_mmap(struct file filp, struct vm_area_struct vma)
	{
	struct drm_file *file_priv = filp->private_data;
	struct ast_private *ast = file_priv->minor->dev->dev_private;

	return ttm_bo_mmap(filp, vma, &ast->ttm.bdev);
	}