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1408 serge 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 
29
 */
30
 
31
#ifndef _TTM_BO_API_H_
32
#define _TTM_BO_API_H_
33
 
34
#include "drm_hashtab.h"
35
#include 
36
#include 
37
//#include 
1630 serge 38
#include 
1408 serge 39
//#include 
40
//#include 
41
#include 
42
 
43
struct ttm_bo_device;
44
 
45
struct drm_mm_node;
46
 
47
 
48
/**
49
 * struct ttm_placement
50
 *
51
 * @fpfn:		first valid page frame number to put the object
52
 * @lpfn:		last valid page frame number to put the object
53
 * @num_placement:	number of prefered placements
54
 * @placement:		prefered placements
55
 * @num_busy_placement:	number of prefered placements when need to evict buffer
56
 * @busy_placement:	prefered placements when need to evict buffer
57
 *
58
 * Structure indicating the placement you request for an object.
59
 */
60
struct ttm_placement {
61
	unsigned	fpfn;
62
	unsigned	lpfn;
63
	unsigned	num_placement;
64
	const uint32_t	*placement;
65
	unsigned	num_busy_placement;
66
	const uint32_t	*busy_placement;
67
};
68
 
69
 
70
/**
71
 * struct ttm_mem_reg
72
 *
73
 * @mm_node: Memory manager node.
74
 * @size: Requested size of memory region.
75
 * @num_pages: Actual size of memory region in pages.
76
 * @page_alignment: Page alignment.
77
 * @placement: Placement flags.
78
 *
79
 * Structure indicating the placement and space resources used by a
80
 * buffer object.
81
 */
82
 
83
struct ttm_mem_reg {
84
	struct drm_mm_node *mm_node;
85
	unsigned long size;
86
	unsigned long num_pages;
87
	uint32_t page_alignment;
88
	uint32_t mem_type;
89
	uint32_t placement;
90
};
91
 
92
/**
93
 * enum ttm_bo_type
94
 *
95
 * @ttm_bo_type_device:	These are 'normal' buffers that can
96
 * be mmapped by user space. Each of these bos occupy a slot in the
97
 * device address space, that can be used for normal vm operations.
98
 *
99
 * @ttm_bo_type_user: These are user-space memory areas that are made
100
 * available to the GPU by mapping the buffer pages into the GPU aperture
101
 * space. These buffers cannot be mmaped from the device address space.
102
 *
103
 * @ttm_bo_type_kernel: These buffers are like ttm_bo_type_device buffers,
104
 * but they cannot be accessed from user-space. For kernel-only use.
105
 */
106
 
107
enum ttm_bo_type {
108
	ttm_bo_type_device,
109
	ttm_bo_type_user,
110
	ttm_bo_type_kernel
111
};
112
 
113
struct ttm_tt;
114
 
115
/**
116
 * struct ttm_buffer_object
117
 *
118
 * @bdev: Pointer to the buffer object device structure.
119
 * @buffer_start: The virtual user-space start address of ttm_bo_type_user
120
 * buffers.
121
 * @type: The bo type.
122
 * @destroy: Destruction function. If NULL, kfree is used.
123
 * @num_pages: Actual number of pages.
124
 * @addr_space_offset: Address space offset.
125
 * @acc_size: Accounted size for this object.
126
 * @kref: Reference count of this buffer object. When this refcount reaches
127
 * zero, the object is put on the delayed delete list.
128
 * @list_kref: List reference count of this buffer object. This member is
129
 * used to avoid destruction while the buffer object is still on a list.
130
 * Lru lists may keep one refcount, the delayed delete list, and kref != 0
131
 * keeps one refcount. When this refcount reaches zero,
132
 * the object is destroyed.
133
 * @event_queue: Queue for processes waiting on buffer object status change.
134
 * @lock: spinlock protecting mostly synchronization members.
135
 * @mem: structure describing current placement.
136
 * @persistant_swap_storage: Usually the swap storage is deleted for buffers
137
 * pinned in physical memory. If this behaviour is not desired, this member
138
 * holds a pointer to a persistant shmem object.
139
 * @ttm: TTM structure holding system pages.
140
 * @evicted: Whether the object was evicted without user-space knowing.
141
 * @cpu_writes: For synchronization. Number of cpu writers.
142
 * @lru: List head for the lru list.
143
 * @ddestroy: List head for the delayed destroy list.
144
 * @swap: List head for swap LRU list.
145
 * @val_seq: Sequence of the validation holding the @reserved lock.
146
 * Used to avoid starvation when many processes compete to validate the
147
 * buffer. This member is protected by the bo_device::lru_lock.
148
 * @seq_valid: The value of @val_seq is valid. This value is protected by
149
 * the bo_device::lru_lock.
150
 * @reserved: Deadlock-free lock used for synchronization state transitions.
151
 * @sync_obj_arg: Opaque argument to synchronization object function.
152
 * @sync_obj: Pointer to a synchronization object.
153
 * @priv_flags: Flags describing buffer object internal state.
154
 * @vm_rb: Rb node for the vm rb tree.
155
 * @vm_node: Address space manager node.
156
 * @offset: The current GPU offset, which can have different meanings
157
 * depending on the memory type. For SYSTEM type memory, it should be 0.
158
 * @cur_placement: Hint of current placement.
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
	/**
174
	 * Members constant at init.
175
	 */
176
 
177
	struct ttm_bo_global *glob;
178
	struct ttm_bo_device *bdev;
179
	unsigned long buffer_start;
180
	enum ttm_bo_type type;
181
	void (*destroy) (struct ttm_buffer_object *);
182
	unsigned long num_pages;
183
	uint64_t addr_space_offset;
184
	size_t acc_size;
185
 
186
	/**
187
	* Members not needing protection.
188
	*/
189
 
190
   struct kref kref;
191
   struct kref list_kref;
192
//   wait_queue_head_t event_queue;
193
   spinlock_t lock;
194
 
195
	/**
196
	 * Members protected by the bo::reserved lock.
197
	 */
198
 
199
	struct ttm_mem_reg mem;
200
//   struct file *persistant_swap_storage;
201
	struct ttm_tt *ttm;
202
	bool evicted;
203
 
204
	/**
205
	 * Members protected by the bo::reserved lock only when written to.
206
	 */
207
 
208
   atomic_t cpu_writers;
209
 
210
	/**
211
	 * Members protected by the bdev::lru_lock.
212
	 */
213
 
214
	struct list_head lru;
215
	struct list_head ddestroy;
216
	struct list_head swap;
217
	uint32_t val_seq;
218
	bool seq_valid;
219
 
220
	/**
221
	 * Members protected by the bdev::lru_lock
222
	 * only when written to.
223
	 */
224
 
225
   atomic_t reserved;
226
 
227
 
228
	/**
229
	 * Members protected by the bo::lock
230
	 */
231
 
232
	void *sync_obj_arg;
233
	void *sync_obj;
234
	unsigned long priv_flags;
235
 
236
	/**
237
	 * Members protected by the bdev::vm_lock
238
	 */
239
 
240
//   struct rb_node vm_rb;
241
	struct drm_mm_node *vm_node;
242
 
243
 
244
	/**
245
	 * Special members that are protected by the reserve lock
246
	 * and the bo::lock when written to. Can be read with
247
	 * either of these locks held.
248
	 */
249
 
250
	unsigned long offset;
251
	uint32_t cur_placement;
252
};
253
 
254
/**
255
 * struct ttm_bo_kmap_obj
256
 *
257
 * @virtual: The current kernel virtual address.
258
 * @page: The page when kmap'ing a single page.
259
 * @bo_kmap_type: Type of bo_kmap.
260
 *
261
 * Object describing a kernel mapping. Since a TTM bo may be located
262
 * in various memory types with various caching policies, the
263
 * mapping can either be an ioremap, a vmap, a kmap or part of a
264
 * premapped region.
265
 */
266
 
267
#define TTM_BO_MAP_IOMEM_MASK 0x80
268
struct ttm_bo_kmap_obj {
269
	void *virtual;
270
	struct page *page;
271
	enum {
272
		ttm_bo_map_iomap        = 1 | TTM_BO_MAP_IOMEM_MASK,
273
		ttm_bo_map_vmap         = 2,
274
		ttm_bo_map_kmap         = 3,
275
		ttm_bo_map_premapped    = 4 | TTM_BO_MAP_IOMEM_MASK,
276
	} bo_kmap_type;
277
};
278
 
279
/**
280
 * ttm_bo_reference - reference a struct ttm_buffer_object
281
 *
282
 * @bo: The buffer object.
283
 *
284
 * Returns a refcounted pointer to a buffer object.
285
 */
286
 
287
static inline struct ttm_buffer_object *
288
ttm_bo_reference(struct ttm_buffer_object *bo)
289
{
290
	kref_get(&bo->kref);
291
	return bo;
292
}
293
 
294
/**
295
 * ttm_bo_wait - wait for buffer idle.
296
 *
297
 * @bo:  The buffer object.
298
 * @interruptible:  Use interruptible wait.
299
 * @no_wait:  Return immediately if buffer is busy.
300
 *
301
 * This function must be called with the bo::mutex held, and makes
302
 * sure any previous rendering to the buffer is completed.
303
 * Note: It might be necessary to block validations before the
304
 * wait by reserving the buffer.
305
 * Returns -EBUSY if no_wait is true and the buffer is busy.
306
 * Returns -ERESTARTSYS if interrupted by a signal.
307
 */
308
extern int ttm_bo_wait(struct ttm_buffer_object *bo, bool lazy,
309
		       bool interruptible, bool no_wait);
310
/**
311
 * ttm_bo_validate
312
 *
313
 * @bo: The buffer object.
314
 * @placement: Proposed placement for the buffer object.
315
 * @interruptible: Sleep interruptible if sleeping.
2003 serge 316
 * @no_wait_reserve: Return immediately if other buffers are busy.
317
 * @no_wait_gpu: Return immediately if the GPU is busy.
1408 serge 318
 *
319
 * Changes placement and caching policy of the buffer object
320
 * according proposed placement.
321
 * Returns
322
 * -EINVAL on invalid proposed placement.
323
 * -ENOMEM on out-of-memory condition.
324
 * -EBUSY if no_wait is true and buffer busy.
325
 * -ERESTARTSYS if interrupted by a signal.
326
 */
327
extern int ttm_bo_validate(struct ttm_buffer_object *bo,
328
				struct ttm_placement *placement,
2003 serge 329
				bool interruptible, bool no_wait_reserve,
330
				bool no_wait_gpu);
1408 serge 331
 
332
/**
333
 * ttm_bo_unref
334
 *
335
 * @bo: The buffer object.
336
 *
337
 * Unreference and clear a pointer to a buffer object.
338
 */
339
extern void ttm_bo_unref(struct ttm_buffer_object **bo);
340
 
341
/**
342
 * ttm_bo_synccpu_write_grab
343
 *
344
 * @bo: The buffer object:
345
 * @no_wait: Return immediately if buffer is busy.
346
 *
347
 * Synchronizes a buffer object for CPU RW access. This means
348
 * blocking command submission that affects the buffer and
349
 * waiting for buffer idle. This lock is recursive.
350
 * Returns
351
 * -EBUSY if the buffer is busy and no_wait is true.
352
 * -ERESTARTSYS if interrupted by a signal.
353
 */
354
 
355
extern int
356
ttm_bo_synccpu_write_grab(struct ttm_buffer_object *bo, bool no_wait);
357
/**
358
 * ttm_bo_synccpu_write_release:
359
 *
360
 * @bo : The buffer object.
361
 *
362
 * Releases a synccpu lock.
363
 */
364
extern void ttm_bo_synccpu_write_release(struct ttm_buffer_object *bo);
365
 
366
/**
367
 * ttm_bo_init
368
 *
369
 * @bdev: Pointer to a ttm_bo_device struct.
370
 * @bo: Pointer to a ttm_buffer_object to be initialized.
371
 * @size: Requested size of buffer object.
372
 * @type: Requested type of buffer object.
373
 * @flags: Initial placement flags.
374
 * @page_alignment: Data alignment in pages.
375
 * @buffer_start: Virtual address of user space data backing a
376
 * user buffer object.
377
 * @interruptible: If needing to sleep to wait for GPU resources,
378
 * sleep interruptible.
2003 serge 379
 * @persistent_swap_storage: Usually the swap storage is deleted for buffers
1408 serge 380
 * pinned in physical memory. If this behaviour is not desired, this member
2003 serge 381
 * holds a pointer to a persistent shmem object. Typically, this would
1408 serge 382
 * point to the shmem object backing a GEM object if TTM is used to back a
383
 * GEM user interface.
384
 * @acc_size: Accounted size for this object.
385
 * @destroy: Destroy function. Use NULL for kfree().
386
 *
387
 * This function initializes a pre-allocated struct ttm_buffer_object.
388
 * As this object may be part of a larger structure, this function,
389
 * together with the @destroy function,
390
 * enables driver-specific objects derived from a ttm_buffer_object.
391
 * On successful return, the object kref and list_kref are set to 1.
2003 serge 392
 * If a failure occurs, the function will call the @destroy function, or
393
 * kfree() if @destroy is NULL. Thus, after a failure, dereferencing @bo is
394
 * illegal and will likely cause memory corruption.
395
 *
1408 serge 396
 * Returns
397
 * -ENOMEM: Out of memory.
398
 * -EINVAL: Invalid placement flags.
399
 * -ERESTARTSYS: Interrupted by signal while sleeping waiting for resources.
400
 */
401
 
402
extern int ttm_bo_init(struct ttm_bo_device *bdev,
403
			struct ttm_buffer_object *bo,
404
			unsigned long size,
405
			enum ttm_bo_type type,
406
			struct ttm_placement *placement,
407
			uint32_t page_alignment,
408
			unsigned long buffer_start,
409
			bool interrubtible,
2003 serge 410
			struct file *persistent_swap_storage,
1408 serge 411
			size_t acc_size,
412
			void (*destroy) (struct ttm_buffer_object *));
413
/**
414
 * ttm_bo_synccpu_object_init
415
 *
416
 * @bdev: Pointer to a ttm_bo_device struct.
417
 * @bo: Pointer to a ttm_buffer_object to be initialized.
418
 * @size: Requested size of buffer object.
419
 * @type: Requested type of buffer object.
420
 * @flags: Initial placement flags.
421
 * @page_alignment: Data alignment in pages.
422
 * @buffer_start: Virtual address of user space data backing a
423
 * user buffer object.
424
 * @interruptible: If needing to sleep while waiting for GPU resources,
425
 * sleep interruptible.
2003 serge 426
 * @persistent_swap_storage: Usually the swap storage is deleted for buffers
1408 serge 427
 * pinned in physical memory. If this behaviour is not desired, this member
2003 serge 428
 * holds a pointer to a persistent shmem object. Typically, this would
1408 serge 429
 * point to the shmem object backing a GEM object if TTM is used to back a
430
 * GEM user interface.
431
 * @p_bo: On successful completion *p_bo points to the created object.
432
 *
433
 * This function allocates a ttm_buffer_object, and then calls ttm_bo_init
434
 * on that object. The destroy function is set to kfree().
435
 * Returns
436
 * -ENOMEM: Out of memory.
437
 * -EINVAL: Invalid placement flags.
438
 * -ERESTARTSYS: Interrupted by signal while waiting for resources.
439
 */
440
 
441
extern int ttm_bo_create(struct ttm_bo_device *bdev,
442
				unsigned long size,
443
				enum ttm_bo_type type,
444
				struct ttm_placement *placement,
445
				uint32_t page_alignment,
446
				unsigned long buffer_start,
447
				bool interruptible,
2003 serge 448
				struct file *persistent_swap_storage,
1408 serge 449
				struct ttm_buffer_object **p_bo);
450
 
451
/**
452
 * ttm_bo_check_placement
453
 *
454
 * @bo:		the buffer object.
455
 * @placement:	placements
456
 *
457
 * Performs minimal validity checking on an intended change of
458
 * placement flags.
459
 * Returns
460
 * -EINVAL: Intended change is invalid or not allowed.
461
 */
462
extern int ttm_bo_check_placement(struct ttm_buffer_object *bo,
463
					struct ttm_placement *placement);
464
 
465
/**
466
 * ttm_bo_init_mm
467
 *
468
 * @bdev: Pointer to a ttm_bo_device struct.
469
 * @mem_type: The memory type.
470
 * @p_size: size managed area in pages.
471
 *
472
 * Initialize a manager for a given memory type.
473
 * Note: if part of driver firstopen, it must be protected from a
474
 * potentially racing lastclose.
475
 * Returns:
476
 * -EINVAL: invalid size or memory type.
477
 * -ENOMEM: Not enough memory.
478
 * May also return driver-specified errors.
479
 */
480
 
481
extern int ttm_bo_init_mm(struct ttm_bo_device *bdev, unsigned type,
482
				unsigned long p_size);
483
/**
484
 * ttm_bo_clean_mm
485
 *
486
 * @bdev: Pointer to a ttm_bo_device struct.
487
 * @mem_type: The memory type.
488
 *
489
 * Take down a manager for a given memory type after first walking
490
 * the LRU list to evict any buffers left alive.
491
 *
492
 * Normally, this function is part of lastclose() or unload(), and at that
493
 * point there shouldn't be any buffers left created by user-space, since
494
 * there should've been removed by the file descriptor release() method.
495
 * However, before this function is run, make sure to signal all sync objects,
496
 * and verify that the delayed delete queue is empty. The driver must also
497
 * make sure that there are no NO_EVICT buffers present in this memory type
498
 * when the call is made.
499
 *
500
 * If this function is part of a VT switch, the caller must make sure that
501
 * there are no appications currently validating buffers before this
502
 * function is called. The caller can do that by first taking the
503
 * struct ttm_bo_device::ttm_lock in write mode.
504
 *
505
 * Returns:
506
 * -EINVAL: invalid or uninitialized memory type.
507
 * -EBUSY: There are still buffers left in this memory type.
508
 */
509
 
510
extern int ttm_bo_clean_mm(struct ttm_bo_device *bdev, unsigned mem_type);
511
 
512
/**
513
 * ttm_bo_evict_mm
514
 *
515
 * @bdev: Pointer to a ttm_bo_device struct.
516
 * @mem_type: The memory type.
517
 *
518
 * Evicts all buffers on the lru list of the memory type.
519
 * This is normally part of a VT switch or an
520
 * out-of-memory-space-due-to-fragmentation handler.
521
 * The caller must make sure that there are no other processes
522
 * currently validating buffers, and can do that by taking the
523
 * struct ttm_bo_device::ttm_lock in write mode.
524
 *
525
 * Returns:
526
 * -EINVAL: Invalid or uninitialized memory type.
527
 * -ERESTARTSYS: The call was interrupted by a signal while waiting to
528
 * evict a buffer.
529
 */
530
 
531
extern int ttm_bo_evict_mm(struct ttm_bo_device *bdev, unsigned mem_type);
532
 
533
/**
534
 * ttm_kmap_obj_virtual
535
 *
536
 * @map: A struct ttm_bo_kmap_obj returned from ttm_bo_kmap.
537
 * @is_iomem: Pointer to an integer that on return indicates 1 if the
538
 * virtual map is io memory, 0 if normal memory.
539
 *
540
 * Returns the virtual address of a buffer object area mapped by ttm_bo_kmap.
541
 * If *is_iomem is 1 on return, the virtual address points to an io memory area,
542
 * that should strictly be accessed by the iowriteXX() and similar functions.
543
 */
544
 
545
static inline void *ttm_kmap_obj_virtual(struct ttm_bo_kmap_obj *map,
546
					 bool *is_iomem)
547
{
548
	*is_iomem = !!(map->bo_kmap_type & TTM_BO_MAP_IOMEM_MASK);
549
	return map->virtual;
550
}
551
 
552
/**
553
 * ttm_bo_kmap
554
 *
555
 * @bo: The buffer object.
556
 * @start_page: The first page to map.
557
 * @num_pages: Number of pages to map.
558
 * @map: pointer to a struct ttm_bo_kmap_obj representing the map.
559
 *
560
 * Sets up a kernel virtual mapping, using ioremap, vmap or kmap to the
561
 * data in the buffer object. The ttm_kmap_obj_virtual function can then be
562
 * used to obtain a virtual address to the data.
563
 *
564
 * Returns
565
 * -ENOMEM: Out of memory.
566
 * -EINVAL: Invalid range.
567
 */
568
 
569
extern int ttm_bo_kmap(struct ttm_buffer_object *bo, unsigned long start_page,
570
		       unsigned long num_pages, struct ttm_bo_kmap_obj *map);
571
 
572
/**
573
 * ttm_bo_kunmap
574
 *
575
 * @map: Object describing the map to unmap.
576
 *
577
 * Unmaps a kernel map set up by ttm_bo_kmap.
578
 */
579
 
580
extern void ttm_bo_kunmap(struct ttm_bo_kmap_obj *map);
581
 
582
#if 0
583
#endif
584
 
585
/**
586
 * ttm_fbdev_mmap - mmap fbdev memory backed by a ttm buffer object.
587
 *
588
 * @vma:       vma as input from the fbdev mmap method.
589
 * @bo:        The bo backing the address space. The address space will
590
 * have the same size as the bo, and start at offset 0.
591
 *
592
 * This function is intended to be called by the fbdev mmap method
593
 * if the fbdev address space is to be backed by a bo.
594
 */
595
 
596
extern int ttm_fbdev_mmap(struct vm_area_struct *vma,
597
			  struct ttm_buffer_object *bo);
598
 
599
/**
600
 * ttm_bo_mmap - mmap out of the ttm device address space.
601
 *
602
 * @filp:      filp as input from the mmap method.
603
 * @vma:       vma as input from the mmap method.
604
 * @bdev:      Pointer to the ttm_bo_device with the address space manager.
605
 *
606
 * This function is intended to be called by the device mmap method.
607
 * if the device address space is to be backed by the bo manager.
608
 */
609
 
610
extern int ttm_bo_mmap(struct file *filp, struct vm_area_struct *vma,
611
		       struct ttm_bo_device *bdev);
612
 
613
/**
614
 * ttm_bo_io
615
 *
616
 * @bdev:      Pointer to the struct ttm_bo_device.
617
 * @filp:      Pointer to the struct file attempting to read / write.
618
 * @wbuf:      User-space pointer to address of buffer to write. NULL on read.
619
 * @rbuf:      User-space pointer to address of buffer to read into.
620
 * Null on write.
621
 * @count:     Number of bytes to read / write.
622
 * @f_pos:     Pointer to current file position.
623
 * @write:     1 for read, 0 for write.
624
 *
625
 * This function implements read / write into ttm buffer objects, and is
626
 * intended to
627
 * be called from the fops::read and fops::write method.
628
 * Returns:
629
 * See man (2) write, man(2) read. In particular,
630
 * the function may return -ERESTARTSYS if
631
 * interrupted by a signal.
632
 */
633
 
634
extern ssize_t ttm_bo_io(struct ttm_bo_device *bdev, struct file *filp,
635
			 const char __user *wbuf, char __user *rbuf,
636
			 size_t count, loff_t *f_pos, bool write);
637
 
638
extern void ttm_bo_swapout_all(struct ttm_bo_device *bdev);
639
 
640
#endif