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