1 /**************************************************************************
2  *
3  * Copyright (c) 2006-2009 Vmware, Inc., Palo Alto, CA., USA
4  * All Rights Reserved.
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a
7  * copy of this software and associated documentation files (the
8  * "Software"), to deal in the Software without restriction, including
9  * without limitation the rights to use, copy, modify, merge, publish,
10  * distribute, sub license, and/or sell copies of the Software, and to
11  * permit persons to whom the Software is furnished to do so, subject to
12  * the following conditions:
13  *
14  * The above copyright notice and this permission notice (including the
15  * next paragraph) shall be included in all copies or substantial portions
16  * of the Software.
17  *
18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
21  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
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23  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
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26  **************************************************************************/
27 /*
28  * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
29  */
30 #ifndef _TTM_BO_DRIVER_H_
31 #define _TTM_BO_DRIVER_H_
32 
33 #include <ttm/ttm_bo_api.h>
34 #include <ttm/ttm_memory.h>
35 #include <ttm/ttm_module.h>
36 #include <ttm/ttm_placement.h>
37 #include <drm/drm_agpsupport.h>
38 #include <drm/drm_mm.h>
39 #include <drm/drm_global.h>
40 #include <drm/drm_vma_manager.h>
41 #include <linux/workqueue.h>
42 #include <linux/fs.h>
43 #include <linux/spinlock.h>
44 #include <linux/reservation.h>
45 #include <asm/page.h>
46 
47 struct ttm_backend_func {
48 	/**
49 	 * struct ttm_backend_func member bind
50 	 *
51 	 * @ttm: Pointer to a struct ttm_tt.
52 	 * @bo_mem: Pointer to a struct ttm_mem_reg describing the
53 	 * memory type and location for binding.
54 	 *
55 	 * Bind the backend pages into the aperture in the location
56 	 * indicated by @bo_mem. This function should be able to handle
57 	 * differences between aperture and system page sizes.
58 	 */
59 	int (*bind) (struct ttm_tt *ttm, struct ttm_mem_reg *bo_mem);
60 
61 	/**
62 	 * struct ttm_backend_func member unbind
63 	 *
64 	 * @ttm: Pointer to a struct ttm_tt.
65 	 *
66 	 * Unbind previously bound backend pages. This function should be
67 	 * able to handle differences between aperture and system page sizes.
68 	 */
69 	int (*unbind) (struct ttm_tt *ttm);
70 
71 	/**
72 	 * struct ttm_backend_func member destroy
73 	 *
74 	 * @ttm: Pointer to a struct ttm_tt.
75 	 *
76 	 * Destroy the backend. This will be call back from ttm_tt_destroy so
77 	 * don't call ttm_tt_destroy from the callback or infinite loop.
78 	 */
79 	void (*destroy) (struct ttm_tt *ttm);
80 };
81 
82 #define TTM_PAGE_FLAG_WRITE           (1 << 3)
83 #define TTM_PAGE_FLAG_SWAPPED         (1 << 4)
84 #define TTM_PAGE_FLAG_PERSISTENT_SWAP (1 << 5)
85 #define TTM_PAGE_FLAG_ZERO_ALLOC      (1 << 6)
86 #define TTM_PAGE_FLAG_DMA32           (1 << 7)
87 #define TTM_PAGE_FLAG_SG              (1 << 8)
88 
89 enum ttm_caching_state {
90 	tt_uncached,
91 	tt_wc,
92 	tt_cached
93 };
94 
95 /**
96  * struct ttm_tt
97  *
98  * @bdev: Pointer to a struct ttm_bo_device.
99  * @func: Pointer to a struct ttm_backend_func that describes
100  * the backend methods.
101  * @dummy_read_page: Page to map where the ttm_tt page array contains a NULL
102  * pointer.
103  * @pages: Array of pages backing the data.
104  * @num_pages: Number of pages in the page array.
105  * @bdev: Pointer to the current struct ttm_bo_device.
106  * @be: Pointer to the ttm backend.
107  * @swap_storage: Pointer to shmem struct file for swap storage.
108  * @caching_state: The current caching state of the pages.
109  * @state: The current binding state of the pages.
110  *
111  * This is a structure holding the pages, caching- and aperture binding
112  * status for a buffer object that isn't backed by fixed (VRAM / AGP)
113  * memory.
114  */
115 
116 struct ttm_tt {
117 	struct ttm_bo_device *bdev;
118 	const struct ttm_backend_func *func;
119 	struct page *dummy_read_page;
120 	struct page **pages;
121 	uint32_t page_flags;
122 	unsigned long num_pages;
123 	struct sg_table *sg; /* for SG objects via dma-buf */
124 	struct ttm_bo_global *glob;
125 #ifdef __NetBSD__
126 	struct uvm_object *swap_storage;
127 	struct pglist pglist;
128 #else
129 	struct file *swap_storage;
130 #endif
131 	enum ttm_caching_state caching_state;
132 	enum {
133 		tt_bound,
134 		tt_unbound,
135 		tt_unpopulated,
136 	} state;
137 };
138 
139 /**
140  * struct ttm_dma_tt
141  *
142  * @ttm: Base ttm_tt struct.
143  * @dma_address: The DMA (bus) addresses of the pages
144  * @pages_list: used by some page allocation backend
145  *
146  * This is a structure holding the pages, caching- and aperture binding
147  * status for a buffer object that isn't backed by fixed (VRAM / AGP)
148  * memory.
149  */
150 struct ttm_dma_tt {
151 	struct ttm_tt ttm;
152 #ifdef __NetBSD__
153 	bus_dma_segment_t *dma_segs;
154 	bus_dmamap_t dma_address;
155 #else
156 	dma_addr_t *dma_address;
157 #endif
158 	struct list_head pages_list;
159 };
160 
161 #define TTM_MEMTYPE_FLAG_FIXED         (1 << 0)	/* Fixed (on-card) PCI memory */
162 #define TTM_MEMTYPE_FLAG_MAPPABLE      (1 << 1)	/* Memory mappable */
163 #define TTM_MEMTYPE_FLAG_CMA           (1 << 3)	/* Can't map aperture */
164 
165 struct ttm_mem_type_manager;
166 
167 struct ttm_mem_type_manager_func {
168 	/**
169 	 * struct ttm_mem_type_manager member init
170 	 *
171 	 * @man: Pointer to a memory type manager.
172 	 * @p_size: Implementation dependent, but typically the size of the
173 	 * range to be managed in pages.
174 	 *
175 	 * Called to initialize a private range manager. The function is
176 	 * expected to initialize the man::priv member.
177 	 * Returns 0 on success, negative error code on failure.
178 	 */
179 	int  (*init)(struct ttm_mem_type_manager *man, unsigned long p_size);
180 
181 	/**
182 	 * struct ttm_mem_type_manager member takedown
183 	 *
184 	 * @man: Pointer to a memory type manager.
185 	 *
186 	 * Called to undo the setup done in init. All allocated resources
187 	 * should be freed.
188 	 */
189 	int  (*takedown)(struct ttm_mem_type_manager *man);
190 
191 	/**
192 	 * struct ttm_mem_type_manager member get_node
193 	 *
194 	 * @man: Pointer to a memory type manager.
195 	 * @bo: Pointer to the buffer object we're allocating space for.
196 	 * @placement: Placement details.
197 	 * @mem: Pointer to a struct ttm_mem_reg to be filled in.
198 	 *
199 	 * This function should allocate space in the memory type managed
200 	 * by @man. Placement details if
201 	 * applicable are given by @placement. If successful,
202 	 * @mem::mm_node should be set to a non-null value, and
203 	 * @mem::start should be set to a value identifying the beginning
204 	 * of the range allocated, and the function should return zero.
205 	 * If the memory region accommodate the buffer object, @mem::mm_node
206 	 * should be set to NULL, and the function should return 0.
207 	 * If a system error occurred, preventing the request to be fulfilled,
208 	 * the function should return a negative error code.
209 	 *
210 	 * Note that @mem::mm_node will only be dereferenced by
211 	 * struct ttm_mem_type_manager functions and optionally by the driver,
212 	 * which has knowledge of the underlying type.
213 	 *
214 	 * This function may not be called from within atomic context, so
215 	 * an implementation can and must use either a mutex or a spinlock to
216 	 * protect any data structures managing the space.
217 	 */
218 	int  (*get_node)(struct ttm_mem_type_manager *man,
219 			 struct ttm_buffer_object *bo,
220 			 struct ttm_placement *placement,
221 			 struct ttm_mem_reg *mem);
222 
223 	/**
224 	 * struct ttm_mem_type_manager member put_node
225 	 *
226 	 * @man: Pointer to a memory type manager.
227 	 * @mem: Pointer to a struct ttm_mem_reg to be filled in.
228 	 *
229 	 * This function frees memory type resources previously allocated
230 	 * and that are identified by @mem::mm_node and @mem::start. May not
231 	 * be called from within atomic context.
232 	 */
233 	void (*put_node)(struct ttm_mem_type_manager *man,
234 			 struct ttm_mem_reg *mem);
235 
236 	/**
237 	 * struct ttm_mem_type_manager member debug
238 	 *
239 	 * @man: Pointer to a memory type manager.
240 	 * @prefix: Prefix to be used in printout to identify the caller.
241 	 *
242 	 * This function is called to print out the state of the memory
243 	 * type manager to aid debugging of out-of-memory conditions.
244 	 * It may not be called from within atomic context.
245 	 */
246 	void (*debug)(struct ttm_mem_type_manager *man, const char *prefix);
247 };
248 
249 /**
250  * struct ttm_mem_type_manager
251  *
252  * @has_type: The memory type has been initialized.
253  * @use_type: The memory type is enabled.
254  * @flags: TTM_MEMTYPE_XX flags identifying the traits of the memory
255  * managed by this memory type.
256  * @gpu_offset: If used, the GPU offset of the first managed page of
257  * fixed memory or the first managed location in an aperture.
258  * @size: Size of the managed region.
259  * @available_caching: A mask of available caching types, TTM_PL_FLAG_XX,
260  * as defined in ttm_placement_common.h
261  * @default_caching: The default caching policy used for a buffer object
262  * placed in this memory type if the user doesn't provide one.
263  * @func: structure pointer implementing the range manager. See above
264  * @priv: Driver private closure for @func.
265  * @io_reserve_mutex: Mutex optionally protecting shared io_reserve structures
266  * @use_io_reserve_lru: Use an lru list to try to unreserve io_mem_regions
267  * reserved by the TTM vm system.
268  * @io_reserve_lru: Optional lru list for unreserving io mem regions.
269  * @io_reserve_fastpath: Only use bdev::driver::io_mem_reserve to obtain
270  * static information. bdev::driver::io_mem_free is never used.
271  * @lru: The lru list for this memory type.
272  *
273  * This structure is used to identify and manage memory types for a device.
274  * It's set up by the ttm_bo_driver::init_mem_type method.
275  */
276 
277 
278 
279 struct ttm_mem_type_manager {
280 	struct ttm_bo_device *bdev;
281 
282 	/*
283 	 * No protection. Constant from start.
284 	 */
285 
286 	bool has_type;
287 	bool use_type;
288 	uint32_t flags;
289 	unsigned long gpu_offset;
290 	uint64_t size;
291 	uint32_t available_caching;
292 	uint32_t default_caching;
293 	const struct ttm_mem_type_manager_func *func;
294 	void *priv;
295 	struct mutex io_reserve_mutex;
296 	bool use_io_reserve_lru;
297 	bool io_reserve_fastpath;
298 
299 	/*
300 	 * Protected by @io_reserve_mutex:
301 	 */
302 
303 	struct list_head io_reserve_lru;
304 
305 	/*
306 	 * Protected by the global->lru_lock.
307 	 */
308 
309 	struct list_head lru;
310 };
311 
312 /**
313  * struct ttm_bo_driver
314  *
315  * @create_ttm_backend_entry: Callback to create a struct ttm_backend.
316  * @invalidate_caches: Callback to invalidate read caches when a buffer object
317  * has been evicted.
318  * @init_mem_type: Callback to initialize a struct ttm_mem_type_manager
319  * structure.
320  * @evict_flags: Callback to obtain placement flags when a buffer is evicted.
321  * @move: Callback for a driver to hook in accelerated functions to
322  * move a buffer.
323  * If set to NULL, a potentially slow memcpy() move is used.
324  * @sync_obj_signaled: See ttm_fence_api.h
325  * @sync_obj_wait: See ttm_fence_api.h
326  * @sync_obj_flush: See ttm_fence_api.h
327  * @sync_obj_unref: See ttm_fence_api.h
328  * @sync_obj_ref: See ttm_fence_api.h
329  */
330 
331 struct ttm_bo_driver {
332 	/**
333 	 * ttm_tt_create
334 	 *
335 	 * @bdev: pointer to a struct ttm_bo_device:
336 	 * @size: Size of the data needed backing.
337 	 * @page_flags: Page flags as identified by TTM_PAGE_FLAG_XX flags.
338 	 * @dummy_read_page: See struct ttm_bo_device.
339 	 *
340 	 * Create a struct ttm_tt to back data with system memory pages.
341 	 * No pages are actually allocated.
342 	 * Returns:
343 	 * NULL: Out of memory.
344 	 */
345 	struct ttm_tt *(*ttm_tt_create)(struct ttm_bo_device *bdev,
346 					unsigned long size,
347 					uint32_t page_flags,
348 					struct page *dummy_read_page);
349 
350 	/**
351 	 * ttm_tt_populate
352 	 *
353 	 * @ttm: The struct ttm_tt to contain the backing pages.
354 	 *
355 	 * Allocate all backing pages
356 	 * Returns:
357 	 * -ENOMEM: Out of memory.
358 	 */
359 	int (*ttm_tt_populate)(struct ttm_tt *ttm);
360 
361 	/**
362 	 * ttm_tt_unpopulate
363 	 *
364 	 * @ttm: The struct ttm_tt to contain the backing pages.
365 	 *
366 	 * Free all backing page
367 	 */
368 	void (*ttm_tt_unpopulate)(struct ttm_tt *ttm);
369 
370 	/**
371 	 * ttm_tt_swapout
372 	 *
373 	 * @ttm: The struct ttm_tt to contain the backing pages.
374 	 *
375 	 * Deactivate all backing pages, but don't free them
376 	 */
377 	void (*ttm_tt_swapout)(struct ttm_tt *ttm);
378 
379 	/**
380 	 * struct ttm_bo_driver member invalidate_caches
381 	 *
382 	 * @bdev: the buffer object device.
383 	 * @flags: new placement of the rebound buffer object.
384 	 *
385 	 * A previosly evicted buffer has been rebound in a
386 	 * potentially new location. Tell the driver that it might
387 	 * consider invalidating read (texture) caches on the next command
388 	 * submission as a consequence.
389 	 */
390 
391 	int (*invalidate_caches) (struct ttm_bo_device *bdev, uint32_t flags);
392 	int (*init_mem_type) (struct ttm_bo_device *bdev, uint32_t type,
393 			      struct ttm_mem_type_manager *man);
394 	/**
395 	 * struct ttm_bo_driver member evict_flags:
396 	 *
397 	 * @bo: the buffer object to be evicted
398 	 *
399 	 * Return the bo flags for a buffer which is not mapped to the hardware.
400 	 * These will be placed in proposed_flags so that when the move is
401 	 * finished, they'll end up in bo->mem.flags
402 	 */
403 
404 	 void(*evict_flags) (struct ttm_buffer_object *bo,
405 				struct ttm_placement *placement);
406 	/**
407 	 * struct ttm_bo_driver member move:
408 	 *
409 	 * @bo: the buffer to move
410 	 * @evict: whether this motion is evicting the buffer from
411 	 * the graphics address space
412 	 * @interruptible: Use interruptible sleeps if possible when sleeping.
413 	 * @no_wait: whether this should give up and return -EBUSY
414 	 * if this move would require sleeping
415 	 * @new_mem: the new memory region receiving the buffer
416 	 *
417 	 * Move a buffer between two memory regions.
418 	 */
419 	int (*move) (struct ttm_buffer_object *bo,
420 		     bool evict, bool interruptible,
421 		     bool no_wait_gpu,
422 		     struct ttm_mem_reg *new_mem);
423 
424 	/**
425 	 * struct ttm_bo_driver_member verify_access
426 	 *
427 	 * @bo: Pointer to a buffer object.
428 	 * @filp: Pointer to a struct file trying to access the object.
429 	 *
430 	 * Called from the map / write / read methods to verify that the
431 	 * caller is permitted to access the buffer object.
432 	 * This member may be set to NULL, which will refuse this kind of
433 	 * access for all buffer objects.
434 	 * This function should return 0 if access is granted, -EPERM otherwise.
435 	 */
436 	int (*verify_access) (struct ttm_buffer_object *bo,
437 			      struct file *filp);
438 
439 	/**
440 	 * In case a driver writer dislikes the TTM fence objects,
441 	 * the driver writer can replace those with sync objects of
442 	 * his / her own. If it turns out that no driver writer is
443 	 * using these. I suggest we remove these hooks and plug in
444 	 * fences directly. The bo driver needs the following functionality:
445 	 * See the corresponding functions in the fence object API
446 	 * documentation.
447 	 */
448 
449 	bool (*sync_obj_signaled) (void *sync_obj);
450 	int (*sync_obj_wait) (void *sync_obj,
451 			      bool lazy, bool interruptible);
452 	int (*sync_obj_flush) (void *sync_obj);
453 	void (*sync_obj_unref) (void **sync_obj);
454 	void *(*sync_obj_ref) (void *sync_obj);
455 
456 	/* hook to notify driver about a driver move so it
457 	 * can do tiling things */
458 	void (*move_notify)(struct ttm_buffer_object *bo,
459 			    struct ttm_mem_reg *new_mem);
460 	/* notify the driver we are taking a fault on this BO
461 	 * and have reserved it */
462 	int (*fault_reserve_notify)(struct ttm_buffer_object *bo);
463 
464 	/**
465 	 * notify the driver that we're about to swap out this bo
466 	 */
467 	void (*swap_notify) (struct ttm_buffer_object *bo);
468 
469 	/**
470 	 * Driver callback on when mapping io memory (for bo_move_memcpy
471 	 * for instance). TTM will take care to call io_mem_free whenever
472 	 * the mapping is not use anymore. io_mem_reserve & io_mem_free
473 	 * are balanced.
474 	 */
475 	int (*io_mem_reserve)(struct ttm_bo_device *bdev, struct ttm_mem_reg *mem);
476 	void (*io_mem_free)(struct ttm_bo_device *bdev, struct ttm_mem_reg *mem);
477 
478 #ifdef __NetBSD__
479 	const struct uvm_pagerops *ttm_uvm_ops;
480 #endif
481 };
482 
483 /**
484  * struct ttm_bo_global_ref - Argument to initialize a struct ttm_bo_global.
485  */
486 
487 struct ttm_bo_global_ref {
488 	struct drm_global_reference ref;
489 	struct ttm_mem_global *mem_glob;
490 };
491 
492 /**
493  * struct ttm_bo_global - Buffer object driver global data.
494  *
495  * @mem_glob: Pointer to a struct ttm_mem_global object for accounting.
496  * @dummy_read_page: Pointer to a dummy page used for mapping requests
497  * of unpopulated pages.
498  * @shrink: A shrink callback object used for buffer object swap.
499  * @device_list_mutex: Mutex protecting the device list.
500  * This mutex is held while traversing the device list for pm options.
501  * @lru_lock: Spinlock protecting the bo subsystem lru lists.
502  * @device_list: List of buffer object devices.
503  * @swap_lru: Lru list of buffer objects used for swapping.
504  */
505 
506 struct ttm_bo_global {
507 
508 	/**
509 	 * Constant after init.
510 	 */
511 
512 #ifndef __NetBSD__
513 	struct kobject kobj;
514 #endif
515 	struct ttm_mem_global *mem_glob;
516 	struct page *dummy_read_page;
517 	struct ttm_mem_shrink shrink;
518 	struct mutex device_list_mutex;
519 	spinlock_t lru_lock;
520 
521 	/**
522 	 * Protected by device_list_mutex.
523 	 */
524 	struct list_head device_list;
525 
526 	/**
527 	 * Protected by the lru_lock.
528 	 */
529 	struct list_head swap_lru;
530 
531 	/**
532 	 * Internal protection.
533 	 */
534 	atomic_t bo_count;
535 };
536 
537 
538 #define TTM_NUM_MEM_TYPES 8
539 
540 #define TTM_BO_PRIV_FLAG_MOVING  0	/* Buffer object is moving and needs
541 					   idling before CPU mapping */
542 #define TTM_BO_PRIV_FLAG_MAX 1
543 /**
544  * struct ttm_bo_device - Buffer object driver device-specific data.
545  *
546  * @driver: Pointer to a struct ttm_bo_driver struct setup by the driver.
547  * @man: An array of mem_type_managers.
548  * @fence_lock: Protects the synchronizing members on *all* bos belonging
549  * to this device.
550  * @vma_manager: Address space manager
551  * lru_lock: Spinlock that protects the buffer+device lru lists and
552  * ddestroy lists.
553  * @val_seq: Current validation sequence.
554  * @dev_mapping: A pointer to the struct address_space representing the
555  * device address space.
556  * @wq: Work queue structure for the delayed delete workqueue.
557  *
558  */
559 
560 struct ttm_bo_device {
561 
562 	/*
563 	 * Constant after bo device init / atomic.
564 	 */
565 	struct list_head device_list;
566 	struct ttm_bo_global *glob;
567 	struct ttm_bo_driver *driver;
568 	struct ttm_mem_type_manager man[TTM_NUM_MEM_TYPES];
569 	spinlock_t fence_lock;
570 
571 	/*
572 	 * Protected by internal locks.
573 	 */
574 	struct drm_vma_offset_manager vma_manager;
575 
576 	/*
577 	 * Protected by the global:lru lock.
578 	 */
579 	struct list_head ddestroy;
580 	uint32_t val_seq;
581 
582 	/*
583 	 * Protected by load / firstopen / lastclose /unload sync.
584 	 */
585 
586 #ifdef __NetBSD__
587 	bus_space_tag_t memt;
588 	bus_dma_tag_t dmat;
589 #else
590 	struct address_space *dev_mapping;
591 #endif
592 
593 	/*
594 	 * Internal protection.
595 	 */
596 
597 	struct delayed_work wq;
598 
599 	bool need_dma32;
600 };
601 
602 /**
603  * ttm_flag_masked
604  *
605  * @old: Pointer to the result and original value.
606  * @new: New value of bits.
607  * @mask: Mask of bits to change.
608  *
609  * Convenience function to change a number of bits identified by a mask.
610  */
611 
612 static inline uint32_t
ttm_flag_masked(uint32_t * old,uint32_t new,uint32_t mask)613 ttm_flag_masked(uint32_t *old, uint32_t new, uint32_t mask)
614 {
615 	*old ^= (*old ^ new) & mask;
616 	return *old;
617 }
618 
619 /**
620  * ttm_tt_init
621  *
622  * @ttm: The struct ttm_tt.
623  * @bdev: pointer to a struct ttm_bo_device:
624  * @size: Size of the data needed backing.
625  * @page_flags: Page flags as identified by TTM_PAGE_FLAG_XX flags.
626  * @dummy_read_page: See struct ttm_bo_device.
627  *
628  * Create a struct ttm_tt to back data with system memory pages.
629  * No pages are actually allocated.
630  * Returns:
631  * NULL: Out of memory.
632  */
633 extern int ttm_tt_init(struct ttm_tt *ttm, struct ttm_bo_device *bdev,
634 			unsigned long size, uint32_t page_flags,
635 			struct page *dummy_read_page);
636 extern int ttm_dma_tt_init(struct ttm_dma_tt *ttm_dma, struct ttm_bo_device *bdev,
637 			   unsigned long size, uint32_t page_flags,
638 			   struct page *dummy_read_page);
639 
640 /**
641  * ttm_tt_fini
642  *
643  * @ttm: the ttm_tt structure.
644  *
645  * Free memory of ttm_tt structure
646  */
647 extern void ttm_tt_fini(struct ttm_tt *ttm);
648 extern void ttm_dma_tt_fini(struct ttm_dma_tt *ttm_dma);
649 
650 /**
651  * ttm_ttm_bind:
652  *
653  * @ttm: The struct ttm_tt containing backing pages.
654  * @bo_mem: The struct ttm_mem_reg identifying the binding location.
655  *
656  * Bind the pages of @ttm to an aperture location identified by @bo_mem
657  */
658 extern int ttm_tt_bind(struct ttm_tt *ttm, struct ttm_mem_reg *bo_mem);
659 
660 /**
661  * ttm_ttm_destroy:
662  *
663  * @ttm: The struct ttm_tt.
664  *
665  * Unbind, unpopulate and destroy common struct ttm_tt.
666  */
667 extern void ttm_tt_destroy(struct ttm_tt *ttm);
668 
669 /**
670  * ttm_ttm_unbind:
671  *
672  * @ttm: The struct ttm_tt.
673  *
674  * Unbind a struct ttm_tt.
675  */
676 extern void ttm_tt_unbind(struct ttm_tt *ttm);
677 
678 #ifdef __NetBSD__
679 /**
680  * ttm_tt_wire
681  *
682  * @ttm The struct ttm_tt.
683  *
684  * Wire the pages of a ttm_tt, allocating pages for it if necessary.
685  */
686 extern int ttm_tt_wire(struct ttm_tt *ttm);
687 
688 /**
689  * ttm_tt_unwire
690  *
691  * @ttm The struct ttm_tt.
692  *
693  * Unwire the pages of a ttm_tt.
694  */
695 extern void ttm_tt_unwire(struct ttm_tt *ttm);
696 #else
697 /**
698  * ttm_tt_swapin:
699  *
700  * @ttm: The struct ttm_tt.
701  *
702  * Swap in a previously swap out ttm_tt.
703  */
704 extern int ttm_tt_swapin(struct ttm_tt *ttm);
705 #endif
706 
707 /**
708  * ttm_tt_cache_flush:
709  *
710  * @pages: An array of pointers to struct page:s to flush.
711  * @num_pages: Number of pages to flush.
712  *
713  * Flush the data of the indicated pages from the cpu caches.
714  * This is used when changing caching attributes of the pages from
715  * cache-coherent.
716  */
717 extern void ttm_tt_cache_flush(struct page *pages[], unsigned long num_pages);
718 
719 /**
720  * ttm_tt_set_placement_caching:
721  *
722  * @ttm A struct ttm_tt the backing pages of which will change caching policy.
723  * @placement: Flag indicating the desired caching policy.
724  *
725  * This function will change caching policy of any default kernel mappings of
726  * the pages backing @ttm. If changing from cached to uncached or
727  * write-combined,
728  * all CPU caches will first be flushed to make sure the data of the pages
729  * hit RAM. This function may be very costly as it involves global TLB
730  * and cache flushes and potential page splitting / combining.
731  */
732 extern int ttm_tt_set_placement_caching(struct ttm_tt *ttm, uint32_t placement);
733 extern int ttm_tt_swapout(struct ttm_tt *ttm,
734 			  struct file *persistent_swap_storage);
735 
736 /**
737  * ttm_tt_unpopulate - free pages from a ttm
738  *
739  * @ttm: Pointer to the ttm_tt structure
740  *
741  * Calls the driver method to free all pages from a ttm
742  */
743 extern void ttm_tt_unpopulate(struct ttm_tt *ttm);
744 
745 /*
746  * ttm_bo.c
747  */
748 
749 /**
750  * ttm_mem_reg_is_pci
751  *
752  * @bdev: Pointer to a struct ttm_bo_device.
753  * @mem: A valid struct ttm_mem_reg.
754  *
755  * Returns true if the memory described by @mem is PCI memory,
756  * false otherwise.
757  */
758 extern bool ttm_mem_reg_is_pci(struct ttm_bo_device *bdev,
759 				   struct ttm_mem_reg *mem);
760 
761 /**
762  * ttm_bo_mem_space
763  *
764  * @bo: Pointer to a struct ttm_buffer_object. the data of which
765  * we want to allocate space for.
766  * @proposed_placement: Proposed new placement for the buffer object.
767  * @mem: A struct ttm_mem_reg.
768  * @interruptible: Sleep interruptible when sliping.
769  * @no_wait_gpu: Return immediately if the GPU is busy.
770  *
771  * Allocate memory space for the buffer object pointed to by @bo, using
772  * the placement flags in @mem, potentially evicting other idle buffer objects.
773  * This function may sleep while waiting for space to become available.
774  * Returns:
775  * -EBUSY: No space available (only if no_wait == 1).
776  * -ENOMEM: Could not allocate memory for the buffer object, either due to
777  * fragmentation or concurrent allocators.
778  * -ERESTARTSYS: An interruptible sleep was interrupted by a signal.
779  */
780 extern int ttm_bo_mem_space(struct ttm_buffer_object *bo,
781 				struct ttm_placement *placement,
782 				struct ttm_mem_reg *mem,
783 				bool interruptible,
784 				bool no_wait_gpu);
785 
786 extern void ttm_bo_mem_put(struct ttm_buffer_object *bo,
787 			   struct ttm_mem_reg *mem);
788 extern void ttm_bo_mem_put_locked(struct ttm_buffer_object *bo,
789 				  struct ttm_mem_reg *mem);
790 
791 extern void ttm_bo_global_release(struct drm_global_reference *ref);
792 extern int ttm_bo_global_init(struct drm_global_reference *ref);
793 
794 extern int ttm_bo_device_release(struct ttm_bo_device *bdev);
795 
796 /**
797  * ttm_bo_device_init
798  *
799  * @bdev: A pointer to a struct ttm_bo_device to initialize.
800  * @glob: A pointer to an initialized struct ttm_bo_global.
801  * @driver: A pointer to a struct ttm_bo_driver set up by the caller.
802  * @mapping: The address space to use for this bo.
803  * @file_page_offset: Offset into the device address space that is available
804  * for buffer data. This ensures compatibility with other users of the
805  * address space.
806  *
807  * Initializes a struct ttm_bo_device:
808  * Returns:
809  * !0: Failure.
810  */
811 extern int ttm_bo_device_init(struct ttm_bo_device *bdev,
812 			      struct ttm_bo_global *glob,
813 			      struct ttm_bo_driver *driver,
814 #ifdef __NetBSD__
815 			      bus_space_tag_t memt,
816 			      bus_dma_tag_t dmat,
817 #else
818 			      struct address_space *mapping,
819 #endif
820 			      uint64_t file_page_offset, bool need_dma32);
821 
822 /**
823  * ttm_bo_unmap_virtual
824  *
825  * @bo: tear down the virtual mappings for this BO
826  */
827 extern void ttm_bo_unmap_virtual(struct ttm_buffer_object *bo);
828 
829 /**
830  * ttm_bo_unmap_virtual
831  *
832  * @bo: tear down the virtual mappings for this BO
833  *
834  * The caller must take ttm_mem_io_lock before calling this function.
835  */
836 extern void ttm_bo_unmap_virtual_locked(struct ttm_buffer_object *bo);
837 
838 extern int ttm_mem_io_reserve_vm(struct ttm_buffer_object *bo);
839 extern void ttm_mem_io_free_vm(struct ttm_buffer_object *bo);
840 extern int ttm_mem_io_lock(struct ttm_mem_type_manager *man,
841 			   bool interruptible);
842 extern void ttm_mem_io_unlock(struct ttm_mem_type_manager *man);
843 
844 extern void ttm_bo_del_sub_from_lru(struct ttm_buffer_object *bo);
845 extern void ttm_bo_add_to_lru(struct ttm_buffer_object *bo);
846 
847 /**
848  * __ttm_bo_reserve:
849  *
850  * @bo: A pointer to a struct ttm_buffer_object.
851  * @interruptible: Sleep interruptible if waiting.
852  * @no_wait: Don't sleep while trying to reserve, rather return -EBUSY.
853  * @use_ticket: If @bo is already reserved, Only sleep waiting for
854  * it to become unreserved if @ticket->stamp is older.
855  *
856  * Will not remove reserved buffers from the lru lists.
857  * Otherwise identical to ttm_bo_reserve.
858  *
859  * Returns:
860  * -EDEADLK: The reservation may cause a deadlock.
861  * Release all buffer reservations, wait for @bo to become unreserved and
862  * try again. (only if use_sequence == 1).
863  * -ERESTARTSYS: A wait for the buffer to become unreserved was interrupted by
864  * a signal. Release all buffer reservations and return to user-space.
865  * -EBUSY: The function needed to sleep, but @no_wait was true
866  * -EALREADY: Bo already reserved using @ticket. This error code will only
867  * be returned if @use_ticket is set to true.
868  */
__ttm_bo_reserve(struct ttm_buffer_object * bo,bool interruptible,bool no_wait,bool use_ticket,struct ww_acquire_ctx * ticket)869 static inline int __ttm_bo_reserve(struct ttm_buffer_object *bo,
870 				   bool interruptible,
871 				   bool no_wait, bool use_ticket,
872 				   struct ww_acquire_ctx *ticket)
873 {
874 	int ret = 0;
875 
876 	if (no_wait) {
877 		bool success;
878 		if (WARN_ON(ticket))
879 			return -EBUSY;
880 
881 		success = ww_mutex_trylock(&bo->resv->lock);
882 		return success ? 0 : -EBUSY;
883 	}
884 
885 	if (interruptible)
886 		ret = ww_mutex_lock_interruptible(&bo->resv->lock, ticket);
887 	else
888 		ret = ww_mutex_lock(&bo->resv->lock, ticket);
889 	if (ret == -EINTR)
890 		return -ERESTARTSYS;
891 	return ret;
892 }
893 
894 /**
895  * ttm_bo_reserve:
896  *
897  * @bo: A pointer to a struct ttm_buffer_object.
898  * @interruptible: Sleep interruptible if waiting.
899  * @no_wait: Don't sleep while trying to reserve, rather return -EBUSY.
900  * @use_ticket: If @bo is already reserved, Only sleep waiting for
901  * it to become unreserved if @ticket->stamp is older.
902  *
903  * Locks a buffer object for validation. (Or prevents other processes from
904  * locking it for validation) and removes it from lru lists, while taking
905  * a number of measures to prevent deadlocks.
906  *
907  * Deadlocks may occur when two processes try to reserve multiple buffers in
908  * different order, either by will or as a result of a buffer being evicted
909  * to make room for a buffer already reserved. (Buffers are reserved before
910  * they are evicted). The following algorithm prevents such deadlocks from
911  * occurring:
912  * Processes attempting to reserve multiple buffers other than for eviction,
913  * (typically execbuf), should first obtain a unique 32-bit
914  * validation sequence number,
915  * and call this function with @use_ticket == 1 and @ticket->stamp == the unique
916  * sequence number. If upon call of this function, the buffer object is already
917  * reserved, the validation sequence is checked against the validation
918  * sequence of the process currently reserving the buffer,
919  * and if the current validation sequence is greater than that of the process
920  * holding the reservation, the function returns -EAGAIN. Otherwise it sleeps
921  * waiting for the buffer to become unreserved, after which it retries
922  * reserving.
923  * The caller should, when receiving an -EAGAIN error
924  * release all its buffer reservations, wait for @bo to become unreserved, and
925  * then rerun the validation with the same validation sequence. This procedure
926  * will always guarantee that the process with the lowest validation sequence
927  * will eventually succeed, preventing both deadlocks and starvation.
928  *
929  * Returns:
930  * -EDEADLK: The reservation may cause a deadlock.
931  * Release all buffer reservations, wait for @bo to become unreserved and
932  * try again. (only if use_sequence == 1).
933  * -ERESTARTSYS: A wait for the buffer to become unreserved was interrupted by
934  * a signal. Release all buffer reservations and return to user-space.
935  * -EBUSY: The function needed to sleep, but @no_wait was true
936  * -EALREADY: Bo already reserved using @ticket. This error code will only
937  * be returned if @use_ticket is set to true.
938  */
ttm_bo_reserve(struct ttm_buffer_object * bo,bool interruptible,bool no_wait,bool use_ticket,struct ww_acquire_ctx * ticket)939 static inline int ttm_bo_reserve(struct ttm_buffer_object *bo,
940 				 bool interruptible,
941 				 bool no_wait, bool use_ticket,
942 				 struct ww_acquire_ctx *ticket)
943 {
944 	int ret;
945 
946 	WARN_ON(!kref_referenced_p(&bo->kref));
947 
948 	ret = __ttm_bo_reserve(bo, interruptible, no_wait, use_ticket, ticket);
949 	if (likely(ret == 0))
950 		ttm_bo_del_sub_from_lru(bo);
951 
952 	return ret;
953 }
954 
955 /**
956  * ttm_bo_reserve_slowpath:
957  * @bo: A pointer to a struct ttm_buffer_object.
958  * @interruptible: Sleep interruptible if waiting.
959  * @sequence: Set (@bo)->sequence to this value after lock
960  *
961  * This is called after ttm_bo_reserve returns -EAGAIN and we backed off
962  * from all our other reservations. Because there are no other reservations
963  * held by us, this function cannot deadlock any more.
964  */
ttm_bo_reserve_slowpath(struct ttm_buffer_object * bo,bool interruptible,struct ww_acquire_ctx * ticket)965 static inline int ttm_bo_reserve_slowpath(struct ttm_buffer_object *bo,
966 					  bool interruptible,
967 					  struct ww_acquire_ctx *ticket)
968 {
969 	int ret = 0;
970 
971 	WARN_ON(!kref_referenced_p(&bo->kref));
972 
973 	if (interruptible)
974 		ret = ww_mutex_lock_slow_interruptible(&bo->resv->lock,
975 						       ticket);
976 	else
977 		ww_mutex_lock_slow(&bo->resv->lock, ticket);
978 
979 	if (likely(ret == 0))
980 		ttm_bo_del_sub_from_lru(bo);
981 	else if (ret == -EINTR)
982 		ret = -ERESTARTSYS;
983 
984 	return ret;
985 }
986 
987 /**
988  * __ttm_bo_unreserve
989  * @bo: A pointer to a struct ttm_buffer_object.
990  *
991  * Unreserve a previous reservation of @bo where the buffer object is
992  * already on lru lists.
993  */
__ttm_bo_unreserve(struct ttm_buffer_object * bo)994 static inline void __ttm_bo_unreserve(struct ttm_buffer_object *bo)
995 {
996 	ww_mutex_unlock(&bo->resv->lock);
997 }
998 
999 /**
1000  * ttm_bo_unreserve
1001  *
1002  * @bo: A pointer to a struct ttm_buffer_object.
1003  *
1004  * Unreserve a previous reservation of @bo.
1005  */
ttm_bo_unreserve(struct ttm_buffer_object * bo)1006 static inline void ttm_bo_unreserve(struct ttm_buffer_object *bo)
1007 {
1008 	if (!(bo->mem.placement & TTM_PL_FLAG_NO_EVICT)) {
1009 		spin_lock(&bo->glob->lru_lock);
1010 		ttm_bo_add_to_lru(bo);
1011 		spin_unlock(&bo->glob->lru_lock);
1012 	}
1013 	__ttm_bo_unreserve(bo);
1014 }
1015 
1016 /**
1017  * ttm_bo_unreserve_ticket
1018  * @bo: A pointer to a struct ttm_buffer_object.
1019  * @ticket: ww_acquire_ctx used for reserving
1020  *
1021  * Unreserve a previous reservation of @bo made with @ticket.
1022  */
ttm_bo_unreserve_ticket(struct ttm_buffer_object * bo,struct ww_acquire_ctx * t)1023 static inline void ttm_bo_unreserve_ticket(struct ttm_buffer_object *bo,
1024 					   struct ww_acquire_ctx *t)
1025 {
1026 	ttm_bo_unreserve(bo);
1027 }
1028 
1029 /*
1030  * ttm_bo_util.c
1031  */
1032 
1033 int ttm_mem_io_reserve(struct ttm_bo_device *bdev,
1034 		       struct ttm_mem_reg *mem);
1035 void ttm_mem_io_free(struct ttm_bo_device *bdev,
1036 		     struct ttm_mem_reg *mem);
1037 /**
1038  * ttm_bo_move_ttm
1039  *
1040  * @bo: A pointer to a struct ttm_buffer_object.
1041  * @evict: 1: This is an eviction. Don't try to pipeline.
1042  * @no_wait_gpu: Return immediately if the GPU is busy.
1043  * @new_mem: struct ttm_mem_reg indicating where to move.
1044  *
1045  * Optimized move function for a buffer object with both old and
1046  * new placement backed by a TTM. The function will, if successful,
1047  * free any old aperture space, and set (@new_mem)->mm_node to NULL,
1048  * and update the (@bo)->mem placement flags. If unsuccessful, the old
1049  * data remains untouched, and it's up to the caller to free the
1050  * memory space indicated by @new_mem.
1051  * Returns:
1052  * !0: Failure.
1053  */
1054 
1055 extern int ttm_bo_move_ttm(struct ttm_buffer_object *bo,
1056 			   bool evict, bool no_wait_gpu,
1057 			   struct ttm_mem_reg *new_mem);
1058 
1059 /**
1060  * ttm_bo_move_memcpy
1061  *
1062  * @bo: A pointer to a struct ttm_buffer_object.
1063  * @evict: 1: This is an eviction. Don't try to pipeline.
1064  * @no_wait_gpu: Return immediately if the GPU is busy.
1065  * @new_mem: struct ttm_mem_reg indicating where to move.
1066  *
1067  * Fallback move function for a mappable buffer object in mappable memory.
1068  * The function will, if successful,
1069  * free any old aperture space, and set (@new_mem)->mm_node to NULL,
1070  * and update the (@bo)->mem placement flags. If unsuccessful, the old
1071  * data remains untouched, and it's up to the caller to free the
1072  * memory space indicated by @new_mem.
1073  * Returns:
1074  * !0: Failure.
1075  */
1076 
1077 extern int ttm_bo_move_memcpy(struct ttm_buffer_object *bo,
1078 			      bool evict, bool no_wait_gpu,
1079 			      struct ttm_mem_reg *new_mem);
1080 
1081 /**
1082  * ttm_bo_free_old_node
1083  *
1084  * @bo: A pointer to a struct ttm_buffer_object.
1085  *
1086  * Utility function to free an old placement after a successful move.
1087  */
1088 extern void ttm_bo_free_old_node(struct ttm_buffer_object *bo);
1089 
1090 /**
1091  * ttm_bo_move_accel_cleanup.
1092  *
1093  * @bo: A pointer to a struct ttm_buffer_object.
1094  * @sync_obj: A sync object that signals when moving is complete.
1095  * @evict: This is an evict move. Don't return until the buffer is idle.
1096  * @no_wait_gpu: Return immediately if the GPU is busy.
1097  * @new_mem: struct ttm_mem_reg indicating where to move.
1098  *
1099  * Accelerated move function to be called when an accelerated move
1100  * has been scheduled. The function will create a new temporary buffer object
1101  * representing the old placement, and put the sync object on both buffer
1102  * objects. After that the newly created buffer object is unref'd to be
1103  * destroyed when the move is complete. This will help pipeline
1104  * buffer moves.
1105  */
1106 
1107 extern int ttm_bo_move_accel_cleanup(struct ttm_buffer_object *bo,
1108 				     void *sync_obj,
1109 				     bool evict, bool no_wait_gpu,
1110 				     struct ttm_mem_reg *new_mem);
1111 /**
1112  * ttm_io_prot
1113  *
1114  * @c_state: Caching state.
1115  * @tmp: Page protection flag for a normal, cached mapping.
1116  *
1117  * Utility function that returns the pgprot_t that should be used for
1118  * setting up a PTE with the caching model indicated by @c_state.
1119  */
1120 extern pgprot_t ttm_io_prot(uint32_t caching_flags, pgprot_t tmp);
1121 
1122 extern const struct ttm_mem_type_manager_func ttm_bo_manager_func;
1123 
1124 #if (defined(CONFIG_AGP) || (defined(CONFIG_AGP_MODULE) && defined(MODULE)))
1125 #define TTM_HAS_AGP
1126 #include <linux/agp_backend.h>
1127 
1128 /**
1129  * ttm_agp_tt_create
1130  *
1131  * @bdev: Pointer to a struct ttm_bo_device.
1132  * @bridge: The agp bridge this device is sitting on.
1133  * @size: Size of the data needed backing.
1134  * @page_flags: Page flags as identified by TTM_PAGE_FLAG_XX flags.
1135  * @dummy_read_page: See struct ttm_bo_device.
1136  *
1137  *
1138  * Create a TTM backend that uses the indicated AGP bridge as an aperture
1139  * for TT memory. This function uses the linux agpgart interface to
1140  * bind and unbind memory backing a ttm_tt.
1141  */
1142 extern struct ttm_tt *ttm_agp_tt_create(struct ttm_bo_device *bdev,
1143 					struct agp_bridge_data *bridge,
1144 					unsigned long size, uint32_t page_flags,
1145 					struct page *dummy_read_page);
1146 int ttm_agp_tt_populate(struct ttm_tt *ttm);
1147 void ttm_agp_tt_unpopulate(struct ttm_tt *ttm);
1148 #endif
1149 
1150 #endif
1151