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