include/drm/ttm/ttm_device.h - linux - Git at Google

 /*
  * Copyright 2020 Advanced Micro Devices, 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, sublicense,
  * 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 above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
  *
  * 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 NONINFRINGEMENT.  IN NO EVENT SHALL
  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) 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.
  *
  * Authors: Christian König
  */

 #ifndef _TTM_DEVICE_H_
 #define _TTM_DEVICE_H_

 #include <linux/types.h>
 #include <linux/workqueue.h>
 #include <drm/ttm/ttm_resource.h>
 #include <drm/ttm/ttm_pool.h>

 struct ttm_device;
 struct ttm_placement;
 struct ttm_buffer_object;
 struct ttm_operation_ctx;

 /**
  * struct ttm_global - Buffer object driver global data.
  */
 extern struct ttm_global {

 	/**
 	 * @dummy_read_page: Pointer to a dummy page used for mapping requests
 	 * of unpopulated pages. Constant after init.
 	 */
 	struct page *dummy_read_page;

 	/**
 	 * @device_list: List of buffer object devices. Protected by
 	 * ttm_global_mutex.
 	 */
 	struct list_head device_list;

 	/**
 	 * @bo_count: Number of buffer objects allocated by devices.
 	 */
 	atomic_t bo_count;
 } ttm_glob;

 struct ttm_device_funcs {
 	/**
 	 * ttm_tt_create
 	 *
 	 * @bo: The buffer object to create the ttm for.
 	 * @page_flags: Page flags as identified by TTM_TT_FLAG_XX flags.
 	 *
 	 * Create a struct ttm_tt to back data with system memory pages.
 	 * No pages are actually allocated.
 	 * Returns:
 	 * NULL: Out of memory.
 	 */
 	struct ttm_tt *(*ttm_tt_create)(struct ttm_buffer_object *bo,
 					uint32_t page_flags);

 	/**
 	 * ttm_tt_populate
 	 *
 	 * @ttm: The struct ttm_tt to contain the backing pages.
 	 *
 	 * Allocate all backing pages
 	 * Returns:
 	 * -ENOMEM: Out of memory.
 	 */
 	int (*ttm_tt_populate)(struct ttm_device *bdev,
 			       struct ttm_tt *ttm,
 			       struct ttm_operation_ctx *ctx);

 	/**
 	 * ttm_tt_unpopulate
 	 *
 	 * @ttm: The struct ttm_tt to contain the backing pages.
 	 *
 	 * Free all backing page
 	 */
 	void (*ttm_tt_unpopulate)(struct ttm_device *bdev,
 				  struct ttm_tt *ttm);

 	/**
 	 * ttm_tt_destroy
 	 *
 	 * @bdev: Pointer to a ttm device
 	 * @ttm: Pointer to a struct ttm_tt.
 	 *
 	 * Destroy the backend. This will be call back from ttm_tt_destroy so
 	 * don't call ttm_tt_destroy from the callback or infinite loop.
 	 */
 	void (*ttm_tt_destroy)(struct ttm_device *bdev, struct ttm_tt *ttm);

 	/**
 	 * struct ttm_bo_driver member eviction_valuable
 	 *
 	 * @bo: the buffer object to be evicted
 	 * @place: placement we need room for
 	 *
 	 * Check with the driver if it is valuable to evict a BO to make room
 	 * for a certain placement.
 	 */
 	bool (*eviction_valuable)(struct ttm_buffer_object *bo,
 				  const struct ttm_place *place);
 	/**
 	 * struct ttm_bo_driver member evict_flags:
 	 *
 	 * @bo: the buffer object to be evicted
 	 *
 	 * Return the bo flags for a buffer which is not mapped to the hardware.
 	 * These will be placed in proposed_flags so that when the move is
 	 * finished, they'll end up in bo->mem.flags
 	 * This should not cause multihop evictions, and the core will warn
 	 * if one is proposed.
 	 */

 	void (*evict_flags)(struct ttm_buffer_object *bo,
 			    struct ttm_placement *placement);

 	/**
 	 * struct ttm_bo_driver member move:
 	 *
 	 * @bo: the buffer to move
 	 * @evict: whether this motion is evicting the buffer from
 	 * the graphics address space
 	 * @ctx: context for this move with parameters
 	 * @new_mem: the new memory region receiving the buffer
 	 * @hop: placement for driver directed intermediate hop
 	 *
 	 * Move a buffer between two memory regions.
 	 * Returns errno -EMULTIHOP if driver requests a hop
 	 */
 	int (*move)(struct ttm_buffer_object *bo, bool evict,
 		    struct ttm_operation_ctx *ctx,
 		    struct ttm_resource *new_mem,
 		    struct ttm_place *hop);

 	/**
 	 * Hook to notify driver about a resource delete.
 	 */
 	void (*delete_mem_notify)(struct ttm_buffer_object *bo);

 	/**
 	 * notify the driver that we're about to swap out this bo
 	 */
 	void (*swap_notify)(struct ttm_buffer_object *bo);

 	/**
 	 * Driver callback on when mapping io memory (for bo_move_memcpy
 	 * for instance). TTM will take care to call io_mem_free whenever
 	 * the mapping is not use anymore. io_mem_reserve & io_mem_free
 	 * are balanced.
 	 */
 	int (*io_mem_reserve)(struct ttm_device *bdev,
 			      struct ttm_resource *mem);
 	void (*io_mem_free)(struct ttm_device *bdev,
 			    struct ttm_resource *mem);

 	/**
 	 * Return the pfn for a given page_offset inside the BO.
 	 *
 	 * @bo: the BO to look up the pfn for
 	 * @page_offset: the offset to look up
 	 */
 	unsigned long (*io_mem_pfn)(struct ttm_buffer_object *bo,
 				    unsigned long page_offset);

 	/**
 	 * Read/write memory buffers for ptrace access
 	 *
 	 * @bo: the BO to access
 	 * @offset: the offset from the start of the BO
 	 * @buf: pointer to source/destination buffer
 	 * @len: number of bytes to copy
 	 * @write: whether to read (0) from or write (non-0) to BO
 	 *
 	 * If successful, this function should return the number of
 	 * bytes copied, -EIO otherwise. If the number of bytes
 	 * returned is < len, the function may be called again with
 	 * the remainder of the buffer to copy.
 	 */
 	int (*access_memory)(struct ttm_buffer_object *bo, unsigned long offset,
 			     void *buf, int len, int write);

 	/**
 	 * Notify the driver that we're about to release a BO
 	 *
 	 * @bo: BO that is about to be released
 	 *
 	 * Gives the driver a chance to do any cleanup, including
 	 * adding fences that may force a delayed delete
 	 */
 	void (*release_notify)(struct ttm_buffer_object *bo);
 };

 /**
  * struct ttm_device - Buffer object driver device-specific data.
  */
 struct ttm_device {
 	/**
 	 * @device_list: Our entry in the global device list.
 	 * Constant after bo device init
 	 */
 	struct list_head device_list;

 	/**
 	 * @funcs: Function table for the device.
 	 * Constant after bo device init
 	 */
 	const struct ttm_device_funcs *funcs;

 	/**
 	 * @sysman: Resource manager for the system domain.
 	 * Access via ttm_manager_type.
 	 */
 	struct ttm_resource_manager sysman;

 	/**
 	 * @man_drv: An array of resource_managers, one per resource type.
 	 */
 	struct ttm_resource_manager *man_drv[TTM_NUM_MEM_TYPES];

 	/**
 	 * @vma_manager: Address space manager for finding BOs to mmap.
 	 */
 	struct drm_vma_offset_manager *vma_manager;

 	/**
 	 * @pool: page pool for the device.
 	 */
 	struct ttm_pool pool;

 	/**
 	 * @lru_lock: Protection for the per manager LRU and ddestroy lists.
 	 */
 	spinlock_t lru_lock;

 	/**
 	 * @pinned: Buffer objects which are pinned and so not on any LRU list.
 	 */
 	struct list_head pinned;

 	/**
 	 * @dev_mapping: A pointer to the struct address_space for invalidating
 	 * CPU mappings on buffer move. Protected by load/unload sync.
 	 */
 	struct address_space *dev_mapping;

 	/**
 	 * @wq: Work queue structure for the delayed delete workqueue.
 	 */
 	struct workqueue_struct *wq;
 };

 int ttm_global_swapout(struct ttm_operation_ctx *ctx, gfp_t gfp_flags);
 int ttm_device_swapout(struct ttm_device *bdev, struct ttm_operation_ctx *ctx,
 		       gfp_t gfp_flags);

 static inline struct ttm_resource_manager *
 ttm_manager_type(struct ttm_device *bdev, int mem_type)
 {
 	BUILD_BUG_ON(__builtin_constant_p(mem_type)
 		     && mem_type >= TTM_NUM_MEM_TYPES);
 	return bdev->man_drv[mem_type];
 }

 static inline void ttm_set_driver_manager(struct ttm_device *bdev, int type,
 					  struct ttm_resource_manager *manager)
 {
 	BUILD_BUG_ON(__builtin_constant_p(type) && type >= TTM_NUM_MEM_TYPES);
 	bdev->man_drv[type] = manager;
 }

 int ttm_device_init(struct ttm_device *bdev, const struct ttm_device_funcs *funcs,
 		    struct device *dev, struct address_space *mapping,
 		    struct drm_vma_offset_manager *vma_manager,
 		    bool use_dma_alloc, bool use_dma32);
 void ttm_device_fini(struct ttm_device *bdev);
 void ttm_device_clear_dma_mappings(struct ttm_device *bdev);

 #endif
	/*
	* Copyright 2020 Advanced Micro Devices, 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, sublicense,
	* 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 above copyright notice and this permission notice shall be included in
	* all copies or substantial portions of the Software.
	*
	* 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 NONINFRINGEMENT. IN NO EVENT SHALL
	* THE COPYRIGHT HOLDER(S) OR AUTHOR(S) 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.
	*
	* Authors: Christian König
	*/

	#ifndef _TTM_DEVICE_H_
	#define _TTM_DEVICE_H_

	#include <linux/types.h>
	#include <linux/workqueue.h>
	#include <drm/ttm/ttm_resource.h>
	#include <drm/ttm/ttm_pool.h>

	struct ttm_device;
	struct ttm_placement;
	struct ttm_buffer_object;
	struct ttm_operation_ctx;

	/**
	* struct ttm_global - Buffer object driver global data.
	*/
	extern struct ttm_global {

	/**
	* @dummy_read_page: Pointer to a dummy page used for mapping requests
	* of unpopulated pages. Constant after init.
	*/
	struct page *dummy_read_page;

	/**
	* @device_list: List of buffer object devices. Protected by
	* ttm_global_mutex.
	*/
	struct list_head device_list;

	/**
	* @bo_count: Number of buffer objects allocated by devices.
	*/
	atomic_t bo_count;
	} ttm_glob;

	struct ttm_device_funcs {
	/**
	* ttm_tt_create
	*
	* @bo: The buffer object to create the ttm for.
	* @page_flags: Page flags as identified by TTM_TT_FLAG_XX flags.
	*
	* Create a struct ttm_tt to back data with system memory pages.
	* No pages are actually allocated.
	* Returns:
	* NULL: Out of memory.
	*/
	struct ttm_tt (ttm_tt_create)(struct ttm_buffer_object *bo,
	uint32_t page_flags);

	/**
	* ttm_tt_populate
	*
	* @ttm: The struct ttm_tt to contain the backing pages.
	*
	* Allocate all backing pages
	* Returns:
	* -ENOMEM: Out of memory.
	*/
	int (ttm_tt_populate)(struct ttm_device bdev,
	struct ttm_tt *ttm,
	struct ttm_operation_ctx *ctx);

	/**
	* ttm_tt_unpopulate
	*
	* @ttm: The struct ttm_tt to contain the backing pages.
	*
	* Free all backing page
	*/
	void (ttm_tt_unpopulate)(struct ttm_device bdev,
	struct ttm_tt *ttm);

	/**
	* ttm_tt_destroy
	*
	* @bdev: Pointer to a ttm device
	* @ttm: Pointer to a struct ttm_tt.
	*
	* Destroy the backend. This will be call back from ttm_tt_destroy so
	* don't call ttm_tt_destroy from the callback or infinite loop.
	*/
	void (ttm_tt_destroy)(struct ttm_device bdev, struct ttm_tt *ttm);

	/**
	* struct ttm_bo_driver member eviction_valuable
	*
	* @bo: the buffer object to be evicted
	* @place: placement we need room for
	*
	* Check with the driver if it is valuable to evict a BO to make room
	* for a certain placement.
	*/
	bool (eviction_valuable)(struct ttm_buffer_object bo,
	const struct ttm_place *place);
	/**
	* struct ttm_bo_driver member evict_flags:
	*
	* @bo: the buffer object to be evicted
	*
	* Return the bo flags for a buffer which is not mapped to the hardware.
	* These will be placed in proposed_flags so that when the move is
	* finished, they'll end up in bo->mem.flags
	* This should not cause multihop evictions, and the core will warn
	* if one is proposed.
	*/

	void (evict_flags)(struct ttm_buffer_object bo,
	struct ttm_placement *placement);

	/**
	* struct ttm_bo_driver member move:
	*
	* @bo: the buffer to move
	* @evict: whether this motion is evicting the buffer from
	* the graphics address space
	* @ctx: context for this move with parameters
	* @new_mem: the new memory region receiving the buffer
	* @hop: placement for driver directed intermediate hop
	*
	* Move a buffer between two memory regions.
	* Returns errno -EMULTIHOP if driver requests a hop
	*/
	int (move)(struct ttm_buffer_object bo, bool evict,
	struct ttm_operation_ctx *ctx,
	struct ttm_resource *new_mem,
	struct ttm_place *hop);

	/**
	* Hook to notify driver about a resource delete.
	*/
	void (delete_mem_notify)(struct ttm_buffer_object bo);

	/**
	* notify the driver that we're about to swap out this bo
	*/
	void (swap_notify)(struct ttm_buffer_object bo);

	/**
	* Driver callback on when mapping io memory (for bo_move_memcpy
	* for instance). TTM will take care to call io_mem_free whenever
	* the mapping is not use anymore. io_mem_reserve & io_mem_free
	* are balanced.
	*/
	int (io_mem_reserve)(struct ttm_device bdev,
	struct ttm_resource *mem);
	void (io_mem_free)(struct ttm_device bdev,
	struct ttm_resource *mem);

	/**
	* Return the pfn for a given page_offset inside the BO.
	*
	* @bo: the BO to look up the pfn for
	* @page_offset: the offset to look up
	*/
	unsigned long (io_mem_pfn)(struct ttm_buffer_object bo,
	unsigned long page_offset);

	/**
	* Read/write memory buffers for ptrace access
	*
	* @bo: the BO to access
	* @offset: the offset from the start of the BO
	* @buf: pointer to source/destination buffer
	* @len: number of bytes to copy
	* @write: whether to read (0) from or write (non-0) to BO
	*
	* If successful, this function should return the number of
	* bytes copied, -EIO otherwise. If the number of bytes
	* returned is < len, the function may be called again with
	* the remainder of the buffer to copy.
	*/
	int (access_memory)(struct ttm_buffer_object bo, unsigned long offset,
	void *buf, int len, int write);

	/**
	* Notify the driver that we're about to release a BO
	*
	* @bo: BO that is about to be released
	*
	* Gives the driver a chance to do any cleanup, including
	* adding fences that may force a delayed delete
	*/
	void (release_notify)(struct ttm_buffer_object bo);
	};

	/**
	* struct ttm_device - Buffer object driver device-specific data.
	*/
	struct ttm_device {
	/**
	* @device_list: Our entry in the global device list.
	* Constant after bo device init
	*/
	struct list_head device_list;

	/**
	* @funcs: Function table for the device.
	* Constant after bo device init
	*/
	const struct ttm_device_funcs *funcs;

	/**
	* @sysman: Resource manager for the system domain.
	* Access via ttm_manager_type.
	*/
	struct ttm_resource_manager sysman;

	/**
	* @man_drv: An array of resource_managers, one per resource type.
	*/
	struct ttm_resource_manager *man_drv[TTM_NUM_MEM_TYPES];

	/**
	* @vma_manager: Address space manager for finding BOs to mmap.
	*/
	struct drm_vma_offset_manager *vma_manager;

	/**
	* @pool: page pool for the device.
	*/
	struct ttm_pool pool;

	/**
	* @lru_lock: Protection for the per manager LRU and ddestroy lists.
	*/
	spinlock_t lru_lock;

	/**
	* @pinned: Buffer objects which are pinned and so not on any LRU list.
	*/
	struct list_head pinned;

	/**
	* @dev_mapping: A pointer to the struct address_space for invalidating
	* CPU mappings on buffer move. Protected by load/unload sync.
	*/
	struct address_space *dev_mapping;

	/**
	* @wq: Work queue structure for the delayed delete workqueue.
	*/
	struct workqueue_struct *wq;
	};

	int ttm_global_swapout(struct ttm_operation_ctx *ctx, gfp_t gfp_flags);
	int ttm_device_swapout(struct ttm_device bdev, struct ttm_operation_ctx ctx,
	gfp_t gfp_flags);

	static inline struct ttm_resource_manager *
	ttm_manager_type(struct ttm_device *bdev, int mem_type)
	{
	BUILD_BUG_ON(__builtin_constant_p(mem_type)
	&& mem_type >= TTM_NUM_MEM_TYPES);
	return bdev->man_drv[mem_type];
	}

	static inline void ttm_set_driver_manager(struct ttm_device *bdev, int type,
	struct ttm_resource_manager *manager)
	{
	BUILD_BUG_ON(__builtin_constant_p(type) && type >= TTM_NUM_MEM_TYPES);
	bdev->man_drv[type] = manager;
	}

	int ttm_device_init(struct ttm_device bdev, const struct ttm_device_funcs funcs,
	struct device dev, struct address_space mapping,
	struct drm_vma_offset_manager *vma_manager,
	bool use_dma_alloc, bool use_dma32);
	void ttm_device_fini(struct ttm_device *bdev);
	void ttm_device_clear_dma_mappings(struct ttm_device *bdev);

	#endif