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,
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
24 * USE OR OTHER DEALINGS IN THE SOFTWARE.
25 *
26 **************************************************************************/
27 /*
28 * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
29 */
30
31 #ifndef _TTM_BO_API_H_
32 #define _TTM_BO_API_H_
33
34 #include <drm/drm_gem.h>
35 #include <drm/drm_hashtab.h>
36 #include <drm/drm_vma_manager.h>
37 #include <linux/kref.h>
38 #include <linux/list.h>
39 #include <linux/wait.h>
40 #include <linux/mutex.h>
41 #include <linux/mm.h>
42 #include <linux/bitmap.h>
43 #include <linux/dma-resv.h>
44
45 struct ttm_bo_global;
46
47 struct ttm_bo_device;
48
49 struct drm_mm_node;
50
51 struct ttm_placement;
52
53 struct ttm_place;
54
55 struct ttm_lru_bulk_move;
56
57 /**
58 * struct ttm_bus_placement
59 *
60 * @addr: mapped virtual address
61 * @base: bus base address
62 * @is_iomem: is this io memory ?
63 * @size: size in byte
64 * @offset: offset from the base address
65 * @io_reserved_vm: The VM system has a refcount in @io_reserved_count
66 * @io_reserved_count: Refcounting the numbers of callers to ttm_mem_io_reserve
67 *
68 * Structure indicating the bus placement of an object.
69 */
70 struct ttm_bus_placement {
71 void *addr;
72 phys_addr_t base;
73 unsigned long size;
74 unsigned long offset;
75 bool is_iomem;
76 bool io_reserved_vm;
77 uint64_t io_reserved_count;
78 };
79
80
81 /**
82 * struct ttm_mem_reg
83 *
84 * @mm_node: Memory manager node.
85 * @size: Requested size of memory region.
86 * @num_pages: Actual size of memory region in pages.
87 * @page_alignment: Page alignment.
88 * @placement: Placement flags.
89 * @bus: Placement on io bus accessible to the CPU
90 *
91 * Structure indicating the placement and space resources used by a
92 * buffer object.
93 */
94
95 struct ttm_mem_reg {
96 void *mm_node;
97 unsigned long start;
98 unsigned long size;
99 unsigned long num_pages;
100 uint32_t page_alignment;
101 uint32_t mem_type;
102 uint32_t placement;
103 struct ttm_bus_placement bus;
104 };
105
106 /**
107 * enum ttm_bo_type
108 *
109 * @ttm_bo_type_device: These are 'normal' buffers that can
110 * be mmapped by user space. Each of these bos occupy a slot in the
111 * device address space, that can be used for normal vm operations.
112 *
113 * @ttm_bo_type_kernel: These buffers are like ttm_bo_type_device buffers,
114 * but they cannot be accessed from user-space. For kernel-only use.
115 *
116 * @ttm_bo_type_sg: Buffer made from dmabuf sg table shared with another
117 * driver.
118 */
119
120 enum ttm_bo_type {
121 ttm_bo_type_device,
122 ttm_bo_type_kernel,
123 ttm_bo_type_sg
124 };
125
126 struct ttm_tt;
127
128 /**
129 * struct ttm_buffer_object
130 *
131 * @base: drm_gem_object superclass data.
132 * @bdev: Pointer to the buffer object device structure.
133 * @type: The bo type.
134 * @destroy: Destruction function. If NULL, kfree is used.
135 * @num_pages: Actual number of pages.
136 * @acc_size: Accounted size for this object.
137 * @kref: Reference count of this buffer object. When this refcount reaches
138 * zero, the object is put on the delayed delete list.
139 * @list_kref: List reference count of this buffer object. This member is
140 * used to avoid destruction while the buffer object is still on a list.
141 * Lru lists may keep one refcount, the delayed delete list, and kref != 0
142 * keeps one refcount. When this refcount reaches zero,
143 * the object is destroyed.
144 * @mem: structure describing current placement.
145 * @persistent_swap_storage: Usually the swap storage is deleted for buffers
146 * pinned in physical memory. If this behaviour is not desired, this member
147 * holds a pointer to a persistent shmem object.
148 * @ttm: TTM structure holding system pages.
149 * @evicted: Whether the object was evicted without user-space knowing.
150 * @cpu_writes: For synchronization. Number of cpu writers.
151 * @lru: List head for the lru list.
152 * @ddestroy: List head for the delayed destroy list.
153 * @swap: List head for swap LRU list.
154 * @moving: Fence set when BO is moving
155 * @offset: The current GPU offset, which can have different meanings
156 * depending on the memory type. For SYSTEM type memory, it should be 0.
157 * @cur_placement: Hint of current placement.
158 * @wu_mutex: Wait unreserved mutex.
159 *
160 * Base class for TTM buffer object, that deals with data placement and CPU
161 * mappings. GPU mappings are really up to the driver, but for simpler GPUs
162 * the driver can usually use the placement offset @offset directly as the
163 * GPU virtual address. For drivers implementing multiple
164 * GPU memory manager contexts, the driver should manage the address space
165 * in these contexts separately and use these objects to get the correct
166 * placement and caching for these GPU maps. This makes it possible to use
167 * these objects for even quite elaborate memory management schemes.
168 * The destroy member, the API visibility of this object makes it possible
169 * to derive driver specific types.
170 */
171
172 struct ttm_buffer_object {
173 struct drm_gem_object base;
174
175 /**
176 * Members constant at init.
177 */
178
179 struct ttm_bo_device *bdev;
180 enum ttm_bo_type type;
181 void (*destroy) (struct ttm_buffer_object *);
182 unsigned long num_pages;
183 size_t acc_size;
184
185 /**
186 * Members not needing protection.
187 */
188
189 struct kref kref;
190 struct kref list_kref;
191
192 /**
193 * Members protected by the bo::resv::reserved lock.
194 */
195
196 struct ttm_mem_reg mem;
197 struct file *persistent_swap_storage;
198 struct ttm_tt *ttm;
199 bool evicted;
200
201 /**
202 * Members protected by the bo::reserved lock only when written to.
203 */
204
205 atomic_t cpu_writers;
206
207 /**
208 * Members protected by the bdev::lru_lock.
209 */
210
211 struct list_head lru;
212 struct list_head ddestroy;
213 struct list_head swap;
214 struct list_head io_reserve_lru;
215
216 /**
217 * Members protected by a bo reservation.
218 */
219
220 struct dma_fence *moving;
221 unsigned priority;
222
223 /**
224 * Special members that are protected by the reserve lock
225 * and the bo::lock when written to. Can be read with
226 * either of these locks held.
227 */
228
229 uint64_t offset; /* GPU address space is independent of CPU word size */
230
231 struct sg_table *sg;
232
233 struct mutex wu_mutex;
234 };
235
236 /**
237 * struct ttm_bo_kmap_obj
238 *
239 * @virtual: The current kernel virtual address.
240 * @page: The page when kmap'ing a single page.
241 * @bo_kmap_type: Type of bo_kmap.
242 *
243 * Object describing a kernel mapping. Since a TTM bo may be located
244 * in various memory types with various caching policies, the
245 * mapping can either be an ioremap, a vmap, a kmap or part of a
246 * premapped region.
247 */
248
249 #define TTM_BO_MAP_IOMEM_MASK 0x80
250 struct ttm_bo_kmap_obj {
251 void *virtual;
252 struct page *page;
253 enum {
254 ttm_bo_map_iomap = 1 | TTM_BO_MAP_IOMEM_MASK,
255 ttm_bo_map_vmap = 2,
256 ttm_bo_map_kmap = 3,
257 ttm_bo_map_premapped = 4 | TTM_BO_MAP_IOMEM_MASK,
258 } bo_kmap_type;
259 struct ttm_buffer_object *bo;
260 };
261
262 /**
263 * struct ttm_operation_ctx
264 *
265 * @interruptible: Sleep interruptible if sleeping.
266 * @no_wait_gpu: Return immediately if the GPU is busy.
267 * @resv: Reservation object to allow reserved evictions with.
268 * @flags: Including the following flags
269 *
270 * Context for TTM operations like changing buffer placement or general memory
271 * allocation.
272 */
273 struct ttm_operation_ctx {
274 bool interruptible;
275 bool no_wait_gpu;
276 struct dma_resv *resv;
277 uint64_t bytes_moved;
278 uint32_t flags;
279 };
280
281 /* Allow eviction of reserved BOs */
282 #define TTM_OPT_FLAG_ALLOW_RES_EVICT 0x1
283 /* when serving page fault or suspend, allow alloc anyway */
284 #define TTM_OPT_FLAG_FORCE_ALLOC 0x2
285
286 /**
287 * ttm_bo_get - reference a struct ttm_buffer_object
288 *
289 * @bo: The buffer object.
290 */
291 static inline void ttm_bo_get(struct ttm_buffer_object *bo)
292 {
293 kref_get(&bo->kref);
294 }
295
296 /**
297 * ttm_bo_get_unless_zero - reference a struct ttm_buffer_object unless
298 * its refcount has already reached zero.
299 * @bo: The buffer object.
300 *
301 * Used to reference a TTM buffer object in lookups where the object is removed
302 * from the lookup structure during the destructor and for RCU lookups.
303 *
304 * Returns: @bo if the referencing was successful, NULL otherwise.
305 */
306 static inline __must_check struct ttm_buffer_object *
307 ttm_bo_get_unless_zero(struct ttm_buffer_object *bo)
308 {
309 if (!kref_get_unless_zero(&bo->kref))
310 return NULL;
311 return bo;
312 }
313
314 /**
315 * ttm_bo_wait - wait for buffer idle.
316 *
317 * @bo: The buffer object.
318 * @interruptible: Use interruptible wait.
319 * @no_wait: Return immediately if buffer is busy.
320 *
321 * This function must be called with the bo::mutex held, and makes
322 * sure any previous rendering to the buffer is completed.
323 * Note: It might be necessary to block validations before the
324 * wait by reserving the buffer.
325 * Returns -EBUSY if no_wait is true and the buffer is busy.
326 * Returns -ERESTARTSYS if interrupted by a signal.
327 */
328 int ttm_bo_wait(struct ttm_buffer_object *bo, bool interruptible, bool no_wait);
329
330 /**
331 * ttm_bo_mem_compat - Check if proposed placement is compatible with a bo
332 *
333 * @placement: Return immediately if buffer is busy.
334 * @mem: The struct ttm_mem_reg indicating the region where the bo resides
335 * @new_flags: Describes compatible placement found
336 *
337 * Returns true if the placement is compatible
338 */
339 bool ttm_bo_mem_compat(struct ttm_placement *placement, struct ttm_mem_reg *mem,
340 uint32_t *new_flags);
341
342 /**
343 * ttm_bo_validate
344 *
345 * @bo: The buffer object.
346 * @placement: Proposed placement for the buffer object.
347 * @ctx: validation parameters.
348 *
349 * Changes placement and caching policy of the buffer object
350 * according proposed placement.
351 * Returns
352 * -EINVAL on invalid proposed placement.
353 * -ENOMEM on out-of-memory condition.
354 * -EBUSY if no_wait is true and buffer busy.
355 * -ERESTARTSYS if interrupted by a signal.
356 */
357 int ttm_bo_validate(struct ttm_buffer_object *bo,
358 struct ttm_placement *placement,
359 struct ttm_operation_ctx *ctx);
360
361 /**
362 * ttm_bo_put
363 *
364 * @bo: The buffer object.
365 *
366 * Unreference a buffer object.
367 */
368 void ttm_bo_put(struct ttm_buffer_object *bo);
369
370 /**
371 * ttm_bo_add_to_lru
372 *
373 * @bo: The buffer object.
374 *
375 * Add this bo to the relevant mem type lru and, if it's backed by
376 * system pages (ttms) to the swap list.
377 * This function must be called with struct ttm_bo_global::lru_lock held, and
378 * is typically called immediately prior to unreserving a bo.
379 */
380 void ttm_bo_add_to_lru(struct ttm_buffer_object *bo);
381
382 /**
383 * ttm_bo_del_from_lru
384 *
385 * @bo: The buffer object.
386 *
387 * Remove this bo from all lru lists used to lookup and reserve an object.
388 * This function must be called with struct ttm_bo_global::lru_lock held,
389 * and is usually called just immediately after the bo has been reserved to
390 * avoid recursive reservation from lru lists.
391 */
392 void ttm_bo_del_from_lru(struct ttm_buffer_object *bo);
393
394 /**
395 * ttm_bo_move_to_lru_tail
396 *
397 * @bo: The buffer object.
398 * @bulk: optional bulk move structure to remember BO positions
399 *
400 * Move this BO to the tail of all lru lists used to lookup and reserve an
401 * object. This function must be called with struct ttm_bo_global::lru_lock
402 * held, and is used to make a BO less likely to be considered for eviction.
403 */
404 void ttm_bo_move_to_lru_tail(struct ttm_buffer_object *bo,
405 struct ttm_lru_bulk_move *bulk);
406
407 /**
408 * ttm_bo_bulk_move_lru_tail
409 *
410 * @bulk: bulk move structure
411 *
412 * Bulk move BOs to the LRU tail, only valid to use when driver makes sure that
413 * BO order never changes. Should be called with ttm_bo_global::lru_lock held.
414 */
415 void ttm_bo_bulk_move_lru_tail(struct ttm_lru_bulk_move *bulk);
416
417 /**
418 * ttm_bo_lock_delayed_workqueue
419 *
420 * Prevent the delayed workqueue from running.
421 * Returns
422 * True if the workqueue was queued at the time
423 */
424 int ttm_bo_lock_delayed_workqueue(struct ttm_bo_device *bdev);
425
426 /**
427 * ttm_bo_unlock_delayed_workqueue
428 *
429 * Allows the delayed workqueue to run.
430 */
431 void ttm_bo_unlock_delayed_workqueue(struct ttm_bo_device *bdev, int resched);
432
433 /**
434 * ttm_bo_eviction_valuable
435 *
436 * @bo: The buffer object to evict
437 * @place: the placement we need to make room for
438 *
439 * Check if it is valuable to evict the BO to make room for the given placement.
440 */
441 bool ttm_bo_eviction_valuable(struct ttm_buffer_object *bo,
442 const struct ttm_place *place);
443
444 /**
445 * ttm_bo_synccpu_write_grab
446 *
447 * @bo: The buffer object:
448 * @no_wait: Return immediately if buffer is busy.
449 *
450 * Synchronizes a buffer object for CPU RW access. This means
451 * command submission that affects the buffer will return -EBUSY
452 * until ttm_bo_synccpu_write_release is called.
453 *
454 * Returns
455 * -EBUSY if the buffer is busy and no_wait is true.
456 * -ERESTARTSYS if interrupted by a signal.
457 */
458 int ttm_bo_synccpu_write_grab(struct ttm_buffer_object *bo, bool no_wait);
459
460 /**
461 * ttm_bo_synccpu_write_release:
462 *
463 * @bo : The buffer object.
464 *
465 * Releases a synccpu lock.
466 */
467 void ttm_bo_synccpu_write_release(struct ttm_buffer_object *bo);
468
469 /**
470 * ttm_bo_acc_size
471 *
472 * @bdev: Pointer to a ttm_bo_device struct.
473 * @bo_size: size of the buffer object in byte.
474 * @struct_size: size of the structure holding buffer object datas
475 *
476 * Returns size to account for a buffer object
477 */
478 size_t ttm_bo_acc_size(struct ttm_bo_device *bdev,
479 unsigned long bo_size,
480 unsigned struct_size);
481 size_t ttm_bo_dma_acc_size(struct ttm_bo_device *bdev,
482 unsigned long bo_size,
483 unsigned struct_size);
484
485 /**
486 * ttm_bo_init_reserved
487 *
488 * @bdev: Pointer to a ttm_bo_device struct.
489 * @bo: Pointer to a ttm_buffer_object to be initialized.
490 * @size: Requested size of buffer object.
491 * @type: Requested type of buffer object.
492 * @flags: Initial placement flags.
493 * @page_alignment: Data alignment in pages.
494 * @ctx: TTM operation context for memory allocation.
495 * @acc_size: Accounted size for this object.
496 * @resv: Pointer to a dma_resv, or NULL to let ttm allocate one.
497 * @destroy: Destroy function. Use NULL for kfree().
498 *
499 * This function initializes a pre-allocated struct ttm_buffer_object.
500 * As this object may be part of a larger structure, this function,
501 * together with the @destroy function,
502 * enables driver-specific objects derived from a ttm_buffer_object.
503 *
504 * On successful return, the caller owns an object kref to @bo. The kref and
505 * list_kref are usually set to 1, but note that in some situations, other
506 * tasks may already be holding references to @bo as well.
507 * Furthermore, if resv == NULL, the buffer's reservation lock will be held,
508 * and it is the caller's responsibility to call ttm_bo_unreserve.
509 *
510 * If a failure occurs, the function will call the @destroy function, or
511 * kfree() if @destroy is NULL. Thus, after a failure, dereferencing @bo is
512 * illegal and will likely cause memory corruption.
513 *
514 * Returns
515 * -ENOMEM: Out of memory.
516 * -EINVAL: Invalid placement flags.
517 * -ERESTARTSYS: Interrupted by signal while sleeping waiting for resources.
518 */
519
520 int ttm_bo_init_reserved(struct ttm_bo_device *bdev,
521 struct ttm_buffer_object *bo,
522 unsigned long size,
523 enum ttm_bo_type type,
524 struct ttm_placement *placement,
525 uint32_t page_alignment,
526 struct ttm_operation_ctx *ctx,
527 size_t acc_size,
528 struct sg_table *sg,
529 struct dma_resv *resv,
530 void (*destroy) (struct ttm_buffer_object *));
531
532 /**
533 * ttm_bo_init
534 *
535 * @bdev: Pointer to a ttm_bo_device struct.
536 * @bo: Pointer to a ttm_buffer_object to be initialized.
537 * @size: Requested size of buffer object.
538 * @type: Requested type of buffer object.
539 * @flags: Initial placement flags.
540 * @page_alignment: Data alignment in pages.
541 * @interruptible: If needing to sleep to wait for GPU resources,
542 * sleep interruptible.
543 * pinned in physical memory. If this behaviour is not desired, this member
544 * holds a pointer to a persistent shmem object. Typically, this would
545 * point to the shmem object backing a GEM object if TTM is used to back a
546 * GEM user interface.
547 * @acc_size: Accounted size for this object.
548 * @resv: Pointer to a dma_resv, or NULL to let ttm allocate one.
549 * @destroy: Destroy function. Use NULL for kfree().
550 *
551 * This function initializes a pre-allocated struct ttm_buffer_object.
552 * As this object may be part of a larger structure, this function,
553 * together with the @destroy function,
554 * enables driver-specific objects derived from a ttm_buffer_object.
555 *
556 * On successful return, the caller owns an object kref to @bo. The kref and
557 * list_kref are usually set to 1, but note that in some situations, other
558 * tasks may already be holding references to @bo as well.
559 *
560 * If a failure occurs, the function will call the @destroy function, or
561 * kfree() if @destroy is NULL. Thus, after a failure, dereferencing @bo is
562 * illegal and will likely cause memory corruption.
563 *
564 * Returns
565 * -ENOMEM: Out of memory.
566 * -EINVAL: Invalid placement flags.
567 * -ERESTARTSYS: Interrupted by signal while sleeping waiting for resources.
568 */
569 int ttm_bo_init(struct ttm_bo_device *bdev, struct ttm_buffer_object *bo,
570 unsigned long size, enum ttm_bo_type type,
571 struct ttm_placement *placement,
572 uint32_t page_alignment, bool interrubtible, size_t acc_size,
573 struct sg_table *sg, struct dma_resv *resv,
574 void (*destroy) (struct ttm_buffer_object *));
575
576 /**
577 * ttm_bo_create
578 *
579 * @bdev: Pointer to a ttm_bo_device struct.
580 * @size: Requested size of buffer object.
581 * @type: Requested type of buffer object.
582 * @placement: Initial placement.
583 * @page_alignment: Data alignment in pages.
584 * @interruptible: If needing to sleep while waiting for GPU resources,
585 * sleep interruptible.
586 * @p_bo: On successful completion *p_bo points to the created object.
587 *
588 * This function allocates a ttm_buffer_object, and then calls ttm_bo_init
589 * on that object. The destroy function is set to kfree().
590 * Returns
591 * -ENOMEM: Out of memory.
592 * -EINVAL: Invalid placement flags.
593 * -ERESTARTSYS: Interrupted by signal while waiting for resources.
594 */
595 int ttm_bo_create(struct ttm_bo_device *bdev, unsigned long size,
596 enum ttm_bo_type type, struct ttm_placement *placement,
597 uint32_t page_alignment, bool interruptible,
598 struct ttm_buffer_object **p_bo);
599
600 /**
601 * ttm_bo_init_mm
602 *
603 * @bdev: Pointer to a ttm_bo_device struct.
604 * @mem_type: The memory type.
605 * @p_size: size managed area in pages.
606 *
607 * Initialize a manager for a given memory type.
608 * Note: if part of driver firstopen, it must be protected from a
609 * potentially racing lastclose.
610 * Returns:
611 * -EINVAL: invalid size or memory type.
612 * -ENOMEM: Not enough memory.
613 * May also return driver-specified errors.
614 */
615 int ttm_bo_init_mm(struct ttm_bo_device *bdev, unsigned type,
616 unsigned long p_size);
617
618 /**
619 * ttm_bo_clean_mm
620 *
621 * @bdev: Pointer to a ttm_bo_device struct.
622 * @mem_type: The memory type.
623 *
624 * Take down a manager for a given memory type after first walking
625 * the LRU list to evict any buffers left alive.
626 *
627 * Normally, this function is part of lastclose() or unload(), and at that
628 * point there shouldn't be any buffers left created by user-space, since
629 * there should've been removed by the file descriptor release() method.
630 * However, before this function is run, make sure to signal all sync objects,
631 * and verify that the delayed delete queue is empty. The driver must also
632 * make sure that there are no NO_EVICT buffers present in this memory type
633 * when the call is made.
634 *
635 * If this function is part of a VT switch, the caller must make sure that
636 * there are no appications currently validating buffers before this
637 * function is called. The caller can do that by first taking the
638 * struct ttm_bo_device::ttm_lock in write mode.
639 *
640 * Returns:
641 * -EINVAL: invalid or uninitialized memory type.
642 * -EBUSY: There are still buffers left in this memory type.
643 */
644 int ttm_bo_clean_mm(struct ttm_bo_device *bdev, unsigned mem_type);
645
646 /**
647 * ttm_bo_evict_mm
648 *
649 * @bdev: Pointer to a ttm_bo_device struct.
650 * @mem_type: The memory type.
651 *
652 * Evicts all buffers on the lru list of the memory type.
653 * This is normally part of a VT switch or an
654 * out-of-memory-space-due-to-fragmentation handler.
655 * The caller must make sure that there are no other processes
656 * currently validating buffers, and can do that by taking the
657 * struct ttm_bo_device::ttm_lock in write mode.
658 *
659 * Returns:
660 * -EINVAL: Invalid or uninitialized memory type.
661 * -ERESTARTSYS: The call was interrupted by a signal while waiting to
662 * evict a buffer.
663 */
664 int ttm_bo_evict_mm(struct ttm_bo_device *bdev, unsigned mem_type);
665
666 /**
667 * ttm_kmap_obj_virtual
668 *
669 * @map: A struct ttm_bo_kmap_obj returned from ttm_bo_kmap.
670 * @is_iomem: Pointer to an integer that on return indicates 1 if the
671 * virtual map is io memory, 0 if normal memory.
672 *
673 * Returns the virtual address of a buffer object area mapped by ttm_bo_kmap.
674 * If *is_iomem is 1 on return, the virtual address points to an io memory area,
675 * that should strictly be accessed by the iowriteXX() and similar functions.
676 */
677 static inline void *ttm_kmap_obj_virtual(struct ttm_bo_kmap_obj *map,
678 bool *is_iomem)
679 {
680 *is_iomem = !!(map->bo_kmap_type & TTM_BO_MAP_IOMEM_MASK);
681 return map->virtual;
682 }
683
684 /**
685 * ttm_bo_kmap
686 *
687 * @bo: The buffer object.
688 * @start_page: The first page to map.
689 * @num_pages: Number of pages to map.
690 * @map: pointer to a struct ttm_bo_kmap_obj representing the map.
691 *
692 * Sets up a kernel virtual mapping, using ioremap, vmap or kmap to the
693 * data in the buffer object. The ttm_kmap_obj_virtual function can then be
694 * used to obtain a virtual address to the data.
695 *
696 * Returns
697 * -ENOMEM: Out of memory.
698 * -EINVAL: Invalid range.
699 */
700 int ttm_bo_kmap(struct ttm_buffer_object *bo, unsigned long start_page,
701 unsigned long num_pages, struct ttm_bo_kmap_obj *map);
702
703 /**
704 * ttm_bo_kunmap
705 *
706 * @map: Object describing the map to unmap.
707 *
708 * Unmaps a kernel map set up by ttm_bo_kmap.
709 */
710 void ttm_bo_kunmap(struct ttm_bo_kmap_obj *map);
711
712 /**
713 * ttm_fbdev_mmap - mmap fbdev memory backed by a ttm buffer object.
714 *
715 * @vma: vma as input from the fbdev mmap method.
716 * @bo: The bo backing the address space. The address space will
717 * have the same size as the bo, and start at offset 0.
718 *
719 * This function is intended to be called by the fbdev mmap method
720 * if the fbdev address space is to be backed by a bo.
721 */
722 int ttm_fbdev_mmap(struct vm_area_struct *vma, struct ttm_buffer_object *bo);
723
724 /**
725 * ttm_bo_mmap - mmap out of the ttm device address space.
726 *
727 * @filp: filp as input from the mmap method.
728 * @vma: vma as input from the mmap method.
729 * @bdev: Pointer to the ttm_bo_device with the address space manager.
730 *
731 * This function is intended to be called by the device mmap method.
732 * if the device address space is to be backed by the bo manager.
733 */
734 int ttm_bo_mmap(struct file *filp, struct vm_area_struct *vma,
735 struct ttm_bo_device *bdev);
736
737 void *ttm_kmap_atomic_prot(struct page *page, pgprot_t prot);
738
739 void ttm_kunmap_atomic_prot(void *addr, pgprot_t prot);
740
741 /**
742 * ttm_bo_io
743 *
744 * @bdev: Pointer to the struct ttm_bo_device.
745 * @filp: Pointer to the struct file attempting to read / write.
746 * @wbuf: User-space pointer to address of buffer to write. NULL on read.
747 * @rbuf: User-space pointer to address of buffer to read into.
748 * Null on write.
749 * @count: Number of bytes to read / write.
750 * @f_pos: Pointer to current file position.
751 * @write: 1 for read, 0 for write.
752 *
753 * This function implements read / write into ttm buffer objects, and is
754 * intended to
755 * be called from the fops::read and fops::write method.
756 * Returns:
757 * See man (2) write, man(2) read. In particular,
758 * the function may return -ERESTARTSYS if
759 * interrupted by a signal.
760 */
761 ssize_t ttm_bo_io(struct ttm_bo_device *bdev, struct file *filp,
762 const char __user *wbuf, char __user *rbuf,
763 size_t count, loff_t *f_pos, bool write);
764
765 int ttm_bo_swapout(struct ttm_bo_global *glob,
766 struct ttm_operation_ctx *ctx);
767 void ttm_bo_swapout_all(struct ttm_bo_device *bdev);
768 int ttm_bo_wait_unreserved(struct ttm_buffer_object *bo);
769
770 /**
771 * ttm_bo_uses_embedded_gem_object - check if the given bo uses the
772 * embedded drm_gem_object.
773 *
774 * Most ttm drivers are using gem too, so the embedded
775 * ttm_buffer_object.base will be initialized by the driver (before
776 * calling ttm_bo_init). It is also possible to use ttm without gem
777 * though (vmwgfx does that).
778 *
779 * This helper will figure whenever a given ttm bo is a gem object too
780 * or not.
781 *
782 * @bo: The bo to check.
783 */
784 static inline bool ttm_bo_uses_embedded_gem_object(struct ttm_buffer_object *bo)
785 {
786 return bo->base.dev != NULL;
787 }
788 #endif