• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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 #include "ttm_resource.h"
46 
47 struct ttm_bo_global;
48 
49 struct ttm_bo_device;
50 
51 struct drm_mm_node;
52 
53 struct ttm_placement;
54 
55 struct ttm_place;
56 
57 struct ttm_lru_bulk_move;
58 
59 /**
60  * enum ttm_bo_type
61  *
62  * @ttm_bo_type_device:	These are 'normal' buffers that can
63  * be mmapped by user space. Each of these bos occupy a slot in the
64  * device address space, that can be used for normal vm operations.
65  *
66  * @ttm_bo_type_kernel: These buffers are like ttm_bo_type_device buffers,
67  * but they cannot be accessed from user-space. For kernel-only use.
68  *
69  * @ttm_bo_type_sg: Buffer made from dmabuf sg table shared with another
70  * driver.
71  */
72 
73 enum ttm_bo_type {
74 	ttm_bo_type_device,
75 	ttm_bo_type_kernel,
76 	ttm_bo_type_sg
77 };
78 
79 struct ttm_tt;
80 
81 /**
82  * struct ttm_buffer_object
83  *
84  * @base: drm_gem_object superclass data.
85  * @bdev: Pointer to the buffer object device structure.
86  * @type: The bo type.
87  * @destroy: Destruction function. If NULL, kfree is used.
88  * @num_pages: Actual number of pages.
89  * @acc_size: Accounted size for this object.
90  * @kref: Reference count of this buffer object. When this refcount reaches
91  * zero, the object is destroyed or put on the delayed delete list.
92  * @mem: structure describing current placement.
93  * @persistent_swap_storage: Usually the swap storage is deleted for buffers
94  * pinned in physical memory. If this behaviour is not desired, this member
95  * holds a pointer to a persistent shmem object.
96  * @ttm: TTM structure holding system pages.
97  * @evicted: Whether the object was evicted without user-space knowing.
98  * @deleted: True if the object is only a zombie and already deleted.
99  * @lru: List head for the lru list.
100  * @ddestroy: List head for the delayed destroy list.
101  * @swap: List head for swap LRU list.
102  * @moving: Fence set when BO is moving
103  * @offset: The current GPU offset, which can have different meanings
104  * depending on the memory type. For SYSTEM type memory, it should be 0.
105  * @cur_placement: Hint of current placement.
106  *
107  * Base class for TTM buffer object, that deals with data placement and CPU
108  * mappings. GPU mappings are really up to the driver, but for simpler GPUs
109  * the driver can usually use the placement offset @offset directly as the
110  * GPU virtual address. For drivers implementing multiple
111  * GPU memory manager contexts, the driver should manage the address space
112  * in these contexts separately and use these objects to get the correct
113  * placement and caching for these GPU maps. This makes it possible to use
114  * these objects for even quite elaborate memory management schemes.
115  * The destroy member, the API visibility of this object makes it possible
116  * to derive driver specific types.
117  */
118 
119 struct ttm_buffer_object {
120 	struct drm_gem_object base;
121 
122 	/**
123 	 * Members constant at init.
124 	 */
125 
126 	struct ttm_bo_device *bdev;
127 	enum ttm_bo_type type;
128 	void (*destroy) (struct ttm_buffer_object *);
129 	unsigned long num_pages;
130 	size_t acc_size;
131 
132 	/**
133 	* Members not needing protection.
134 	*/
135 	struct kref kref;
136 
137 	/**
138 	 * Members protected by the bo::resv::reserved lock.
139 	 */
140 
141 	struct ttm_resource mem;
142 	struct file *persistent_swap_storage;
143 	struct ttm_tt *ttm;
144 	bool deleted;
145 
146 	/**
147 	 * Members protected by the bdev::lru_lock.
148 	 */
149 
150 	struct list_head lru;
151 	struct list_head ddestroy;
152 	struct list_head swap;
153 
154 	/**
155 	 * Members protected by a bo reservation.
156 	 */
157 
158 	struct dma_fence *moving;
159 	unsigned priority;
160 
161 	/**
162 	 * Special members that are protected by the reserve lock
163 	 * and the bo::lock when written to. Can be read with
164 	 * either of these locks held.
165 	 */
166 
167 	struct sg_table *sg;
168 };
169 
170 /**
171  * struct ttm_bo_kmap_obj
172  *
173  * @virtual: The current kernel virtual address.
174  * @page: The page when kmap'ing a single page.
175  * @bo_kmap_type: Type of bo_kmap.
176  *
177  * Object describing a kernel mapping. Since a TTM bo may be located
178  * in various memory types with various caching policies, the
179  * mapping can either be an ioremap, a vmap, a kmap or part of a
180  * premapped region.
181  */
182 
183 #define TTM_BO_MAP_IOMEM_MASK 0x80
184 struct ttm_bo_kmap_obj {
185 	void *virtual;
186 	struct page *page;
187 	enum {
188 		ttm_bo_map_iomap        = 1 | TTM_BO_MAP_IOMEM_MASK,
189 		ttm_bo_map_vmap         = 2,
190 		ttm_bo_map_kmap         = 3,
191 		ttm_bo_map_premapped    = 4 | TTM_BO_MAP_IOMEM_MASK,
192 	} bo_kmap_type;
193 	struct ttm_buffer_object *bo;
194 };
195 
196 /**
197  * struct ttm_operation_ctx
198  *
199  * @interruptible: Sleep interruptible if sleeping.
200  * @no_wait_gpu: Return immediately if the GPU is busy.
201  * @resv: Reservation object to allow reserved evictions with.
202  * @flags: Including the following flags
203  *
204  * Context for TTM operations like changing buffer placement or general memory
205  * allocation.
206  */
207 struct ttm_operation_ctx {
208 	bool interruptible;
209 	bool no_wait_gpu;
210 	struct dma_resv *resv;
211 	uint64_t bytes_moved;
212 	uint32_t flags;
213 };
214 
215 /* Allow eviction of reserved BOs */
216 #define TTM_OPT_FLAG_ALLOW_RES_EVICT		0x1
217 /* when serving page fault or suspend, allow alloc anyway */
218 #define TTM_OPT_FLAG_FORCE_ALLOC		0x2
219 
220 /**
221  * ttm_bo_get - reference a struct ttm_buffer_object
222  *
223  * @bo: The buffer object.
224  */
ttm_bo_get(struct ttm_buffer_object * bo)225 static inline void ttm_bo_get(struct ttm_buffer_object *bo)
226 {
227 	kref_get(&bo->kref);
228 }
229 
230 /**
231  * ttm_bo_get_unless_zero - reference a struct ttm_buffer_object unless
232  * its refcount has already reached zero.
233  * @bo: The buffer object.
234  *
235  * Used to reference a TTM buffer object in lookups where the object is removed
236  * from the lookup structure during the destructor and for RCU lookups.
237  *
238  * Returns: @bo if the referencing was successful, NULL otherwise.
239  */
240 static inline __must_check struct ttm_buffer_object *
ttm_bo_get_unless_zero(struct ttm_buffer_object * bo)241 ttm_bo_get_unless_zero(struct ttm_buffer_object *bo)
242 {
243 	if (!kref_get_unless_zero(&bo->kref))
244 		return NULL;
245 	return bo;
246 }
247 
248 /**
249  * ttm_bo_wait - wait for buffer idle.
250  *
251  * @bo:  The buffer object.
252  * @interruptible:  Use interruptible wait.
253  * @no_wait:  Return immediately if buffer is busy.
254  *
255  * This function must be called with the bo::mutex held, and makes
256  * sure any previous rendering to the buffer is completed.
257  * Note: It might be necessary to block validations before the
258  * wait by reserving the buffer.
259  * Returns -EBUSY if no_wait is true and the buffer is busy.
260  * Returns -ERESTARTSYS if interrupted by a signal.
261  */
262 int ttm_bo_wait(struct ttm_buffer_object *bo, bool interruptible, bool no_wait);
263 
264 /**
265  * ttm_bo_mem_compat - Check if proposed placement is compatible with a bo
266  *
267  * @placement:  Return immediately if buffer is busy.
268  * @mem:  The struct ttm_resource indicating the region where the bo resides
269  * @new_flags: Describes compatible placement found
270  *
271  * Returns true if the placement is compatible
272  */
273 bool ttm_bo_mem_compat(struct ttm_placement *placement, struct ttm_resource *mem,
274 		       uint32_t *new_flags);
275 
276 /**
277  * ttm_bo_validate
278  *
279  * @bo: The buffer object.
280  * @placement: Proposed placement for the buffer object.
281  * @ctx: validation parameters.
282  *
283  * Changes placement and caching policy of the buffer object
284  * according proposed placement.
285  * Returns
286  * -EINVAL on invalid proposed placement.
287  * -ENOMEM on out-of-memory condition.
288  * -EBUSY if no_wait is true and buffer busy.
289  * -ERESTARTSYS if interrupted by a signal.
290  */
291 int ttm_bo_validate(struct ttm_buffer_object *bo,
292 		    struct ttm_placement *placement,
293 		    struct ttm_operation_ctx *ctx);
294 
295 /**
296  * ttm_bo_put
297  *
298  * @bo: The buffer object.
299  *
300  * Unreference a buffer object.
301  */
302 void ttm_bo_put(struct ttm_buffer_object *bo);
303 
304 /**
305  * ttm_bo_move_to_lru_tail
306  *
307  * @bo: The buffer object.
308  * @bulk: optional bulk move structure to remember BO positions
309  *
310  * Move this BO to the tail of all lru lists used to lookup and reserve an
311  * object. This function must be called with struct ttm_bo_global::lru_lock
312  * held, and is used to make a BO less likely to be considered for eviction.
313  */
314 void ttm_bo_move_to_lru_tail(struct ttm_buffer_object *bo,
315 			     struct ttm_lru_bulk_move *bulk);
316 
317 /**
318  * ttm_bo_bulk_move_lru_tail
319  *
320  * @bulk: bulk move structure
321  *
322  * Bulk move BOs to the LRU tail, only valid to use when driver makes sure that
323  * BO order never changes. Should be called with ttm_bo_global::lru_lock held.
324  */
325 void ttm_bo_bulk_move_lru_tail(struct ttm_lru_bulk_move *bulk);
326 
327 /**
328  * ttm_bo_lock_delayed_workqueue
329  *
330  * Prevent the delayed workqueue from running.
331  * Returns
332  * True if the workqueue was queued at the time
333  */
334 int ttm_bo_lock_delayed_workqueue(struct ttm_bo_device *bdev);
335 
336 /**
337  * ttm_bo_unlock_delayed_workqueue
338  *
339  * Allows the delayed workqueue to run.
340  */
341 void ttm_bo_unlock_delayed_workqueue(struct ttm_bo_device *bdev, int resched);
342 
343 /**
344  * ttm_bo_eviction_valuable
345  *
346  * @bo: The buffer object to evict
347  * @place: the placement we need to make room for
348  *
349  * Check if it is valuable to evict the BO to make room for the given placement.
350  */
351 bool ttm_bo_eviction_valuable(struct ttm_buffer_object *bo,
352 			      const struct ttm_place *place);
353 
354 size_t ttm_bo_dma_acc_size(struct ttm_bo_device *bdev,
355 			   unsigned long bo_size,
356 			   unsigned struct_size);
357 
358 /**
359  * ttm_bo_init_reserved
360  *
361  * @bdev: Pointer to a ttm_bo_device struct.
362  * @bo: Pointer to a ttm_buffer_object to be initialized.
363  * @size: Requested size of buffer object.
364  * @type: Requested type of buffer object.
365  * @flags: Initial placement flags.
366  * @page_alignment: Data alignment in pages.
367  * @ctx: TTM operation context for memory allocation.
368  * @acc_size: Accounted size for this object.
369  * @resv: Pointer to a dma_resv, or NULL to let ttm allocate one.
370  * @destroy: Destroy function. Use NULL for kfree().
371  *
372  * This function initializes a pre-allocated struct ttm_buffer_object.
373  * As this object may be part of a larger structure, this function,
374  * together with the @destroy function,
375  * enables driver-specific objects derived from a ttm_buffer_object.
376  *
377  * On successful return, the caller owns an object kref to @bo. The kref and
378  * list_kref are usually set to 1, but note that in some situations, other
379  * tasks may already be holding references to @bo as well.
380  * Furthermore, if resv == NULL, the buffer's reservation lock will be held,
381  * and it is the caller's responsibility to call ttm_bo_unreserve.
382  *
383  * If a failure occurs, the function will call the @destroy function, or
384  * kfree() if @destroy is NULL. Thus, after a failure, dereferencing @bo is
385  * illegal and will likely cause memory corruption.
386  *
387  * Returns
388  * -ENOMEM: Out of memory.
389  * -EINVAL: Invalid placement flags.
390  * -ERESTARTSYS: Interrupted by signal while sleeping waiting for resources.
391  */
392 
393 int ttm_bo_init_reserved(struct ttm_bo_device *bdev,
394 			 struct ttm_buffer_object *bo,
395 			 unsigned long size,
396 			 enum ttm_bo_type type,
397 			 struct ttm_placement *placement,
398 			 uint32_t page_alignment,
399 			 struct ttm_operation_ctx *ctx,
400 			 size_t acc_size,
401 			 struct sg_table *sg,
402 			 struct dma_resv *resv,
403 			 void (*destroy) (struct ttm_buffer_object *));
404 
405 /**
406  * ttm_bo_init
407  *
408  * @bdev: Pointer to a ttm_bo_device struct.
409  * @bo: Pointer to a ttm_buffer_object to be initialized.
410  * @size: Requested size of buffer object.
411  * @type: Requested type of buffer object.
412  * @flags: Initial placement flags.
413  * @page_alignment: Data alignment in pages.
414  * @interruptible: If needing to sleep to wait for GPU resources,
415  * sleep interruptible.
416  * pinned in physical memory. If this behaviour is not desired, this member
417  * holds a pointer to a persistent shmem object. Typically, this would
418  * point to the shmem object backing a GEM object if TTM is used to back a
419  * GEM user interface.
420  * @acc_size: Accounted size for this object.
421  * @resv: Pointer to a dma_resv, or NULL to let ttm allocate one.
422  * @destroy: Destroy function. Use NULL for kfree().
423  *
424  * This function initializes a pre-allocated struct ttm_buffer_object.
425  * As this object may be part of a larger structure, this function,
426  * together with the @destroy function,
427  * enables driver-specific objects derived from a ttm_buffer_object.
428  *
429  * On successful return, the caller owns an object kref to @bo. The kref and
430  * list_kref are usually set to 1, but note that in some situations, other
431  * tasks may already be holding references to @bo as well.
432  *
433  * If a failure occurs, the function will call the @destroy function, or
434  * kfree() if @destroy is NULL. Thus, after a failure, dereferencing @bo is
435  * illegal and will likely cause memory corruption.
436  *
437  * Returns
438  * -ENOMEM: Out of memory.
439  * -EINVAL: Invalid placement flags.
440  * -ERESTARTSYS: Interrupted by signal while sleeping waiting for resources.
441  */
442 int ttm_bo_init(struct ttm_bo_device *bdev, struct ttm_buffer_object *bo,
443 		unsigned long size, enum ttm_bo_type type,
444 		struct ttm_placement *placement,
445 		uint32_t page_alignment, bool interrubtible, size_t acc_size,
446 		struct sg_table *sg, struct dma_resv *resv,
447 		void (*destroy) (struct ttm_buffer_object *));
448 
449 /**
450  * ttm_bo_create
451  *
452  * @bdev: Pointer to a ttm_bo_device struct.
453  * @size: Requested size of buffer object.
454  * @type: Requested type of buffer object.
455  * @placement: Initial placement.
456  * @page_alignment: Data alignment in pages.
457  * @interruptible: If needing to sleep while waiting for GPU resources,
458  * sleep interruptible.
459  * @p_bo: On successful completion *p_bo points to the created object.
460  *
461  * This function allocates a ttm_buffer_object, and then calls ttm_bo_init
462  * on that object. The destroy function is set to kfree().
463  * Returns
464  * -ENOMEM: Out of memory.
465  * -EINVAL: Invalid placement flags.
466  * -ERESTARTSYS: Interrupted by signal while waiting for resources.
467  */
468 int ttm_bo_create(struct ttm_bo_device *bdev, unsigned long size,
469 		  enum ttm_bo_type type, struct ttm_placement *placement,
470 		  uint32_t page_alignment, bool interruptible,
471 		  struct ttm_buffer_object **p_bo);
472 
473 /**
474  * ttm_bo_evict_mm
475  *
476  * @bdev: Pointer to a ttm_bo_device struct.
477  * @mem_type: The memory type.
478  *
479  * Evicts all buffers on the lru list of the memory type.
480  * This is normally part of a VT switch or an
481  * out-of-memory-space-due-to-fragmentation handler.
482  * The caller must make sure that there are no other processes
483  * currently validating buffers, and can do that by taking the
484  * struct ttm_bo_device::ttm_lock in write mode.
485  *
486  * Returns:
487  * -EINVAL: Invalid or uninitialized memory type.
488  * -ERESTARTSYS: The call was interrupted by a signal while waiting to
489  * evict a buffer.
490  */
491 int ttm_bo_evict_mm(struct ttm_bo_device *bdev, unsigned mem_type);
492 
493 /**
494  * ttm_kmap_obj_virtual
495  *
496  * @map: A struct ttm_bo_kmap_obj returned from ttm_bo_kmap.
497  * @is_iomem: Pointer to an integer that on return indicates 1 if the
498  * virtual map is io memory, 0 if normal memory.
499  *
500  * Returns the virtual address of a buffer object area mapped by ttm_bo_kmap.
501  * If *is_iomem is 1 on return, the virtual address points to an io memory area,
502  * that should strictly be accessed by the iowriteXX() and similar functions.
503  */
ttm_kmap_obj_virtual(struct ttm_bo_kmap_obj * map,bool * is_iomem)504 static inline void *ttm_kmap_obj_virtual(struct ttm_bo_kmap_obj *map,
505 					 bool *is_iomem)
506 {
507 	*is_iomem = !!(map->bo_kmap_type & TTM_BO_MAP_IOMEM_MASK);
508 	return map->virtual;
509 }
510 
511 /**
512  * ttm_bo_kmap
513  *
514  * @bo: The buffer object.
515  * @start_page: The first page to map.
516  * @num_pages: Number of pages to map.
517  * @map: pointer to a struct ttm_bo_kmap_obj representing the map.
518  *
519  * Sets up a kernel virtual mapping, using ioremap, vmap or kmap to the
520  * data in the buffer object. The ttm_kmap_obj_virtual function can then be
521  * used to obtain a virtual address to the data.
522  *
523  * Returns
524  * -ENOMEM: Out of memory.
525  * -EINVAL: Invalid range.
526  */
527 int ttm_bo_kmap(struct ttm_buffer_object *bo, unsigned long start_page,
528 		unsigned long num_pages, struct ttm_bo_kmap_obj *map);
529 
530 /**
531  * ttm_bo_kunmap
532  *
533  * @map: Object describing the map to unmap.
534  *
535  * Unmaps a kernel map set up by ttm_bo_kmap.
536  */
537 void ttm_bo_kunmap(struct ttm_bo_kmap_obj *map);
538 
539 /**
540  * ttm_bo_mmap_obj - mmap memory backed by a ttm buffer object.
541  *
542  * @vma:       vma as input from the fbdev mmap method.
543  * @bo:        The bo backing the address space.
544  *
545  * Maps a buffer object.
546  */
547 int ttm_bo_mmap_obj(struct vm_area_struct *vma, struct ttm_buffer_object *bo);
548 
549 /**
550  * ttm_bo_mmap - mmap out of the ttm device address space.
551  *
552  * @filp:      filp as input from the mmap method.
553  * @vma:       vma as input from the mmap method.
554  * @bdev:      Pointer to the ttm_bo_device with the address space manager.
555  *
556  * This function is intended to be called by the device mmap method.
557  * if the device address space is to be backed by the bo manager.
558  */
559 int ttm_bo_mmap(struct file *filp, struct vm_area_struct *vma,
560 		struct ttm_bo_device *bdev);
561 
562 /**
563  * ttm_bo_io
564  *
565  * @bdev:      Pointer to the struct ttm_bo_device.
566  * @filp:      Pointer to the struct file attempting to read / write.
567  * @wbuf:      User-space pointer to address of buffer to write. NULL on read.
568  * @rbuf:      User-space pointer to address of buffer to read into.
569  * Null on write.
570  * @count:     Number of bytes to read / write.
571  * @f_pos:     Pointer to current file position.
572  * @write:     1 for read, 0 for write.
573  *
574  * This function implements read / write into ttm buffer objects, and is
575  * intended to
576  * be called from the fops::read and fops::write method.
577  * Returns:
578  * See man (2) write, man(2) read. In particular,
579  * the function may return -ERESTARTSYS if
580  * interrupted by a signal.
581  */
582 ssize_t ttm_bo_io(struct ttm_bo_device *bdev, struct file *filp,
583 		  const char __user *wbuf, char __user *rbuf,
584 		  size_t count, loff_t *f_pos, bool write);
585 
586 int ttm_bo_swapout(struct ttm_bo_global *glob,
587 			struct ttm_operation_ctx *ctx);
588 void ttm_bo_swapout_all(void);
589 
590 /**
591  * ttm_bo_uses_embedded_gem_object - check if the given bo uses the
592  * embedded drm_gem_object.
593  *
594  * Most ttm drivers are using gem too, so the embedded
595  * ttm_buffer_object.base will be initialized by the driver (before
596  * calling ttm_bo_init).  It is also possible to use ttm without gem
597  * though (vmwgfx does that).
598  *
599  * This helper will figure whenever a given ttm bo is a gem object too
600  * or not.
601  *
602  * @bo: The bo to check.
603  */
ttm_bo_uses_embedded_gem_object(struct ttm_buffer_object * bo)604 static inline bool ttm_bo_uses_embedded_gem_object(struct ttm_buffer_object *bo)
605 {
606 	return bo->base.dev != NULL;
607 }
608 
609 int ttm_mem_evict_first(struct ttm_bo_device *bdev,
610 			struct ttm_resource_manager *man,
611 			const struct ttm_place *place,
612 			struct ttm_operation_ctx *ctx,
613 			struct ww_acquire_ctx *ticket);
614 
615 /* Default number of pre-faulted pages in the TTM fault handler */
616 #define TTM_BO_VM_NUM_PREFAULT 16
617 
618 vm_fault_t ttm_bo_vm_reserve(struct ttm_buffer_object *bo,
619 			     struct vm_fault *vmf);
620 
621 vm_fault_t ttm_bo_vm_fault_reserved(struct vm_fault *vmf,
622 				    pgprot_t prot,
623 				    pgoff_t num_prefault,
624 				    pgoff_t fault_page_size);
625 
626 vm_fault_t ttm_bo_vm_fault(struct vm_fault *vmf);
627 
628 void ttm_bo_vm_open(struct vm_area_struct *vma);
629 
630 void ttm_bo_vm_close(struct vm_area_struct *vma);
631 
632 int ttm_bo_vm_access(struct vm_area_struct *vma, unsigned long addr,
633 		     void *buf, int len, int write);
634 
635 #endif
636