1 /**************************************************************************
3 * Copyright (c) 2006-2009 Vmware, Inc., Palo Alto, CA., USA
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
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11 * permit persons to whom the Software is furnished to do so, subject to
12 * the following conditions:
14 * The above copyright notice and this permission notice (including the
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18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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20 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
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26 **************************************************************************/
28 * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
30 #ifndef _TTM_BO_DRIVER_H_
31 #define _TTM_BO_DRIVER_H_
33 #include "ttm/ttm_bo_api.h"
34 #include "ttm/ttm_memory.h"
35 #include "ttm/ttm_module.h"
37 #include "drm_global.h"
38 #include "linux/workqueue.h"
40 #include "linux/spinlock.h"
44 struct ttm_backend_func {
46 * struct ttm_backend_func member populate
48 * @backend: Pointer to a struct ttm_backend.
49 * @num_pages: Number of pages to populate.
50 * @pages: Array of pointers to ttm pages.
51 * @dummy_read_page: Page to be used instead of NULL pages in the
54 * Populate the backend with ttm pages. Depending on the backend,
55 * it may or may not copy the @pages array.
57 int (*populate) (struct ttm_backend *backend,
58 unsigned long num_pages, struct page **pages,
59 struct page *dummy_read_page);
61 * struct ttm_backend_func member clear
63 * @backend: Pointer to a struct ttm_backend.
65 * This is an "unpopulate" function. Release all resources
66 * allocated with populate.
68 void (*clear) (struct ttm_backend *backend);
71 * struct ttm_backend_func member bind
73 * @backend: Pointer to a struct ttm_backend.
74 * @bo_mem: Pointer to a struct ttm_mem_reg describing the
75 * memory type and location for binding.
77 * Bind the backend pages into the aperture in the location
78 * indicated by @bo_mem. This function should be able to handle
79 * differences between aperture- and system page sizes.
81 int (*bind) (struct ttm_backend *backend, struct ttm_mem_reg *bo_mem);
84 * struct ttm_backend_func member unbind
86 * @backend: Pointer to a struct ttm_backend.
88 * Unbind previously bound backend pages. This function should be
89 * able to handle differences between aperture- and system page sizes.
91 int (*unbind) (struct ttm_backend *backend);
94 * struct ttm_backend_func member destroy
96 * @backend: Pointer to a struct ttm_backend.
98 * Destroy the backend.
100 void (*destroy) (struct ttm_backend *backend);
106 * @bdev: Pointer to a struct ttm_bo_device.
107 * @flags: For driver use.
108 * @func: Pointer to a struct ttm_backend_func that describes
109 * the backend methods.
114 struct ttm_bo_device *bdev;
116 struct ttm_backend_func *func;
119 #define TTM_PAGE_FLAG_USER (1 << 1)
120 #define TTM_PAGE_FLAG_USER_DIRTY (1 << 2)
121 #define TTM_PAGE_FLAG_WRITE (1 << 3)
122 #define TTM_PAGE_FLAG_SWAPPED (1 << 4)
123 #define TTM_PAGE_FLAG_PERSISTANT_SWAP (1 << 5)
124 #define TTM_PAGE_FLAG_ZERO_ALLOC (1 << 6)
125 #define TTM_PAGE_FLAG_DMA32 (1 << 7)
127 enum ttm_caching_state {
136 * @dummy_read_page: Page to map where the ttm_tt page array contains a NULL
138 * @pages: Array of pages backing the data.
139 * @first_himem_page: Himem pages are put last in the page array, which
140 * enables us to run caching attribute changes on only the first part
141 * of the page array containing lomem pages. This is the index of the
143 * @last_lomem_page: Index of the last lomem page in the page array.
144 * @num_pages: Number of pages in the page array.
145 * @bdev: Pointer to the current struct ttm_bo_device.
146 * @be: Pointer to the ttm backend.
147 * @tsk: The task for user ttm.
148 * @start: virtual address for user ttm.
149 * @swap_storage: Pointer to shmem struct file for swap storage.
150 * @caching_state: The current caching state of the pages.
151 * @state: The current binding state of the pages.
153 * This is a structure holding the pages, caching- and aperture binding
154 * status for a buffer object that isn't backed by fixed (VRAM / AGP)
159 struct page *dummy_read_page;
161 long first_himem_page;
162 long last_lomem_page;
164 unsigned long num_pages;
165 struct ttm_bo_global *glob;
166 struct ttm_backend *be;
167 struct task_struct *tsk;
169 struct file *swap_storage;
170 enum ttm_caching_state caching_state;
178 #define TTM_MEMTYPE_FLAG_FIXED (1 << 0) /* Fixed (on-card) PCI memory */
179 #define TTM_MEMTYPE_FLAG_MAPPABLE (1 << 1) /* Memory mappable */
180 #define TTM_MEMTYPE_FLAG_CMA (1 << 3) /* Can't map aperture */
183 * struct ttm_mem_type_manager
185 * @has_type: The memory type has been initialized.
186 * @use_type: The memory type is enabled.
187 * @flags: TTM_MEMTYPE_XX flags identifying the traits of the memory
188 * managed by this memory type.
189 * @gpu_offset: If used, the GPU offset of the first managed page of
190 * fixed memory or the first managed location in an aperture.
191 * @size: Size of the managed region.
192 * @available_caching: A mask of available caching types, TTM_PL_FLAG_XX,
193 * as defined in ttm_placement_common.h
194 * @default_caching: The default caching policy used for a buffer object
195 * placed in this memory type if the user doesn't provide one.
196 * @manager: The range manager used for this memory type. FIXME: If the aperture
197 * has a page size different from the underlying system, the granularity
198 * of this manager should take care of this. But the range allocating code
199 * in ttm_bo.c needs to be modified for this.
200 * @lru: The lru list for this memory type.
202 * This structure is used to identify and manage memory types for a device.
203 * It's set up by the ttm_bo_driver::init_mem_type method.
206 struct ttm_mem_type_manager;
208 struct ttm_mem_type_manager_func {
209 int (*init)(struct ttm_mem_type_manager *man, unsigned long p_size);
210 int (*takedown)(struct ttm_mem_type_manager *man);
211 int (*get_node)(struct ttm_mem_type_manager *man,
212 struct ttm_buffer_object *bo,
213 struct ttm_placement *placement,
214 struct ttm_mem_reg *mem);
215 void (*put_node)(struct ttm_mem_type_manager *man,
216 struct ttm_mem_reg *mem);
217 void (*debug)(struct ttm_mem_type_manager *man, const char *prefix);
220 struct ttm_mem_type_manager {
221 struct ttm_bo_device *bdev;
224 * No protection. Constant from start.
230 unsigned long gpu_offset;
232 uint32_t available_caching;
233 uint32_t default_caching;
236 * Protected by the bdev->lru_lock.
237 * TODO: Consider one lru_lock per ttm_mem_type_manager.
238 * Plays ill with list removal, though.
240 const struct ttm_mem_type_manager_func *func;
242 struct list_head lru;
246 * struct ttm_bo_driver
248 * @create_ttm_backend_entry: Callback to create a struct ttm_backend.
249 * @invalidate_caches: Callback to invalidate read caches when a buffer object
251 * @init_mem_type: Callback to initialize a struct ttm_mem_type_manager
253 * @evict_flags: Callback to obtain placement flags when a buffer is evicted.
254 * @move: Callback for a driver to hook in accelerated functions to
256 * If set to NULL, a potentially slow memcpy() move is used.
257 * @sync_obj_signaled: See ttm_fence_api.h
258 * @sync_obj_wait: See ttm_fence_api.h
259 * @sync_obj_flush: See ttm_fence_api.h
260 * @sync_obj_unref: See ttm_fence_api.h
261 * @sync_obj_ref: See ttm_fence_api.h
264 struct ttm_bo_driver {
266 * struct ttm_bo_driver member create_ttm_backend_entry
268 * @bdev: The buffer object device.
270 * Create a driver specific struct ttm_backend.
273 struct ttm_backend *(*create_ttm_backend_entry)
274 (struct ttm_bo_device *bdev);
277 * struct ttm_bo_driver member invalidate_caches
279 * @bdev: the buffer object device.
280 * @flags: new placement of the rebound buffer object.
282 * A previosly evicted buffer has been rebound in a
283 * potentially new location. Tell the driver that it might
284 * consider invalidating read (texture) caches on the next command
285 * submission as a consequence.
288 int (*invalidate_caches) (struct ttm_bo_device *bdev, uint32_t flags);
289 int (*init_mem_type) (struct ttm_bo_device *bdev, uint32_t type,
290 struct ttm_mem_type_manager *man);
292 * struct ttm_bo_driver member evict_flags:
294 * @bo: the buffer object to be evicted
296 * Return the bo flags for a buffer which is not mapped to the hardware.
297 * These will be placed in proposed_flags so that when the move is
298 * finished, they'll end up in bo->mem.flags
301 void(*evict_flags) (struct ttm_buffer_object *bo,
302 struct ttm_placement *placement);
304 * struct ttm_bo_driver member move:
306 * @bo: the buffer to move
307 * @evict: whether this motion is evicting the buffer from
308 * the graphics address space
309 * @interruptible: Use interruptible sleeps if possible when sleeping.
310 * @no_wait: whether this should give up and return -EBUSY
311 * if this move would require sleeping
312 * @new_mem: the new memory region receiving the buffer
314 * Move a buffer between two memory regions.
316 int (*move) (struct ttm_buffer_object *bo,
317 bool evict, bool interruptible,
318 bool no_wait_reserve, bool no_wait_gpu,
319 struct ttm_mem_reg *new_mem);
322 * struct ttm_bo_driver_member verify_access
324 * @bo: Pointer to a buffer object.
325 * @filp: Pointer to a struct file trying to access the object.
327 * Called from the map / write / read methods to verify that the
328 * caller is permitted to access the buffer object.
329 * This member may be set to NULL, which will refuse this kind of
330 * access for all buffer objects.
331 * This function should return 0 if access is granted, -EPERM otherwise.
333 int (*verify_access) (struct ttm_buffer_object *bo,
337 * In case a driver writer dislikes the TTM fence objects,
338 * the driver writer can replace those with sync objects of
339 * his / her own. If it turns out that no driver writer is
340 * using these. I suggest we remove these hooks and plug in
341 * fences directly. The bo driver needs the following functionality:
342 * See the corresponding functions in the fence object API
346 bool (*sync_obj_signaled) (void *sync_obj, void *sync_arg);
347 int (*sync_obj_wait) (void *sync_obj, void *sync_arg,
348 bool lazy, bool interruptible);
349 int (*sync_obj_flush) (void *sync_obj, void *sync_arg);
350 void (*sync_obj_unref) (void **sync_obj);
351 void *(*sync_obj_ref) (void *sync_obj);
353 /* hook to notify driver about a driver move so it
354 * can do tiling things */
355 void (*move_notify)(struct ttm_buffer_object *bo,
356 struct ttm_mem_reg *new_mem);
357 /* notify the driver we are taking a fault on this BO
358 * and have reserved it */
359 int (*fault_reserve_notify)(struct ttm_buffer_object *bo);
362 * notify the driver that we're about to swap out this bo
364 void (*swap_notify) (struct ttm_buffer_object *bo);
367 * Driver callback on when mapping io memory (for bo_move_memcpy
368 * for instance). TTM will take care to call io_mem_free whenever
369 * the mapping is not use anymore. io_mem_reserve & io_mem_free
372 int (*io_mem_reserve)(struct ttm_bo_device *bdev, struct ttm_mem_reg *mem);
373 void (*io_mem_free)(struct ttm_bo_device *bdev, struct ttm_mem_reg *mem);
377 * struct ttm_bo_global_ref - Argument to initialize a struct ttm_bo_global.
380 struct ttm_bo_global_ref {
381 struct drm_global_reference ref;
382 struct ttm_mem_global *mem_glob;
386 * struct ttm_bo_global - Buffer object driver global data.
388 * @mem_glob: Pointer to a struct ttm_mem_global object for accounting.
389 * @dummy_read_page: Pointer to a dummy page used for mapping requests
390 * of unpopulated pages.
391 * @shrink: A shrink callback object used for buffer object swap.
392 * @ttm_bo_extra_size: Extra size (sizeof(struct ttm_buffer_object) excluded)
393 * used by a buffer object. This is excluding page arrays and backing pages.
394 * @ttm_bo_size: This is @ttm_bo_extra_size + sizeof(struct ttm_buffer_object).
395 * @device_list_mutex: Mutex protecting the device list.
396 * This mutex is held while traversing the device list for pm options.
397 * @lru_lock: Spinlock protecting the bo subsystem lru lists.
398 * @device_list: List of buffer object devices.
399 * @swap_lru: Lru list of buffer objects used for swapping.
402 struct ttm_bo_global {
405 * Constant after init.
409 struct ttm_mem_global *mem_glob;
410 struct page *dummy_read_page;
411 struct ttm_mem_shrink shrink;
412 size_t ttm_bo_extra_size;
414 struct mutex device_list_mutex;
418 * Protected by device_list_mutex.
420 struct list_head device_list;
423 * Protected by the lru_lock.
425 struct list_head swap_lru;
428 * Internal protection.
434 #define TTM_NUM_MEM_TYPES 8
436 #define TTM_BO_PRIV_FLAG_MOVING 0 /* Buffer object is moving and needs
437 idling before CPU mapping */
438 #define TTM_BO_PRIV_FLAG_MAX 1
440 * struct ttm_bo_device - Buffer object driver device-specific data.
442 * @driver: Pointer to a struct ttm_bo_driver struct setup by the driver.
443 * @man: An array of mem_type_managers.
444 * @addr_space_mm: Range manager for the device address space.
445 * lru_lock: Spinlock that protects the buffer+device lru lists and
447 * @nice_mode: Try nicely to wait for buffer idle when cleaning a manager.
448 * If a GPU lockup has been detected, this is forced to 0.
449 * @dev_mapping: A pointer to the struct address_space representing the
450 * device address space.
451 * @wq: Work queue structure for the delayed delete workqueue.
455 struct ttm_bo_device {
458 * Constant after bo device init / atomic.
460 struct list_head device_list;
461 struct ttm_bo_global *glob;
462 struct ttm_bo_driver *driver;
464 struct ttm_mem_type_manager man[TTM_NUM_MEM_TYPES];
466 * Protected by the vm lock.
468 struct rb_root addr_space_rb;
469 struct drm_mm addr_space_mm;
472 * Protected by the global:lru lock.
474 struct list_head ddestroy;
477 * Protected by load / firstopen / lastclose /unload sync.
481 struct address_space *dev_mapping;
484 * Internal protection.
487 struct delayed_work wq;
495 * @old: Pointer to the result and original value.
496 * @new: New value of bits.
497 * @mask: Mask of bits to change.
499 * Convenience function to change a number of bits identified by a mask.
502 static inline uint32_t
503 ttm_flag_masked(uint32_t *old, uint32_t new, uint32_t mask)
505 *old ^= (*old ^ new) & mask;
512 * @bdev: pointer to a struct ttm_bo_device:
513 * @size: Size of the data needed backing.
514 * @page_flags: Page flags as identified by TTM_PAGE_FLAG_XX flags.
515 * @dummy_read_page: See struct ttm_bo_device.
517 * Create a struct ttm_tt to back data with system memory pages.
518 * No pages are actually allocated.
520 * NULL: Out of memory.
522 extern struct ttm_tt *ttm_tt_create(struct ttm_bo_device *bdev,
525 struct page *dummy_read_page);
530 * @ttm: The struct ttm_tt to populate.
531 * @tsk: A struct task_struct for which @start is a valid user-space address.
532 * @start: A valid user-space address.
533 * @num_pages: Size in pages of the user memory area.
535 * Populate a struct ttm_tt with a user-space memory area after first pinning
536 * the pages backing it.
541 extern int ttm_tt_set_user(struct ttm_tt *ttm,
542 struct task_struct *tsk,
543 unsigned long start, unsigned long num_pages);
548 * @ttm: The struct ttm_tt containing backing pages.
549 * @bo_mem: The struct ttm_mem_reg identifying the binding location.
551 * Bind the pages of @ttm to an aperture location identified by @bo_mem
553 extern int ttm_tt_bind(struct ttm_tt *ttm, struct ttm_mem_reg *bo_mem);
558 * @ttm: The struct ttm_tt to contain the backing pages.
560 * Add backing pages to all of @ttm
562 extern int ttm_tt_populate(struct ttm_tt *ttm);
567 * @ttm: The struct ttm_tt.
569 * Unbind, unpopulate and destroy a struct ttm_tt.
571 extern void ttm_tt_destroy(struct ttm_tt *ttm);
576 * @ttm: The struct ttm_tt.
578 * Unbind a struct ttm_tt.
580 extern void ttm_tt_unbind(struct ttm_tt *ttm);
585 * @ttm: The struct ttm_tt.
586 * @index: Index of the desired page.
588 * Return a pointer to the struct page backing @ttm at page
589 * index @index. If the page is unpopulated, one will be allocated to
590 * populate that index.
595 extern struct page *ttm_tt_get_page(struct ttm_tt *ttm, int index);
598 * ttm_tt_cache_flush:
600 * @pages: An array of pointers to struct page:s to flush.
601 * @num_pages: Number of pages to flush.
603 * Flush the data of the indicated pages from the cpu caches.
604 * This is used when changing caching attributes of the pages from
607 extern void ttm_tt_cache_flush(struct page *pages[], unsigned long num_pages);
610 * ttm_tt_set_placement_caching:
612 * @ttm A struct ttm_tt the backing pages of which will change caching policy.
613 * @placement: Flag indicating the desired caching policy.
615 * This function will change caching policy of any default kernel mappings of
616 * the pages backing @ttm. If changing from cached to uncached or
618 * all CPU caches will first be flushed to make sure the data of the pages
619 * hit RAM. This function may be very costly as it involves global TLB
620 * and cache flushes and potential page splitting / combining.
622 extern int ttm_tt_set_placement_caching(struct ttm_tt *ttm, uint32_t placement);
623 extern int ttm_tt_swapout(struct ttm_tt *ttm,
624 struct file *persistant_swap_storage);
633 * @bdev: Pointer to a struct ttm_bo_device.
634 * @mem: A valid struct ttm_mem_reg.
636 * Returns true if the memory described by @mem is PCI memory,
639 extern bool ttm_mem_reg_is_pci(struct ttm_bo_device *bdev,
640 struct ttm_mem_reg *mem);
645 * @bo: Pointer to a struct ttm_buffer_object. the data of which
646 * we want to allocate space for.
647 * @proposed_placement: Proposed new placement for the buffer object.
648 * @mem: A struct ttm_mem_reg.
649 * @interruptible: Sleep interruptible when sliping.
650 * @no_wait_reserve: Return immediately if other buffers are busy.
651 * @no_wait_gpu: Return immediately if the GPU is busy.
653 * Allocate memory space for the buffer object pointed to by @bo, using
654 * the placement flags in @mem, potentially evicting other idle buffer objects.
655 * This function may sleep while waiting for space to become available.
657 * -EBUSY: No space available (only if no_wait == 1).
658 * -ENOMEM: Could not allocate memory for the buffer object, either due to
659 * fragmentation or concurrent allocators.
660 * -ERESTARTSYS: An interruptible sleep was interrupted by a signal.
662 extern int ttm_bo_mem_space(struct ttm_buffer_object *bo,
663 struct ttm_placement *placement,
664 struct ttm_mem_reg *mem,
666 bool no_wait_reserve, bool no_wait_gpu);
668 extern void ttm_bo_mem_put(struct ttm_buffer_object *bo,
669 struct ttm_mem_reg *mem);
670 extern void ttm_bo_mem_put_locked(struct ttm_buffer_object *bo,
671 struct ttm_mem_reg *mem);
674 * ttm_bo_wait_for_cpu
676 * @bo: Pointer to a struct ttm_buffer_object.
677 * @no_wait: Don't sleep while waiting.
679 * Wait until a buffer object is no longer sync'ed for CPU access.
681 * -EBUSY: Buffer object was sync'ed for CPU access. (only if no_wait == 1).
682 * -ERESTARTSYS: An interruptible sleep was interrupted by a signal.
685 extern int ttm_bo_wait_cpu(struct ttm_buffer_object *bo, bool no_wait);
688 * ttm_bo_pci_offset - Get the PCI offset for the buffer object memory.
690 * @bo Pointer to a struct ttm_buffer_object.
691 * @bus_base On return the base of the PCI region
692 * @bus_offset On return the byte offset into the PCI region
693 * @bus_size On return the byte size of the buffer object or zero if
694 * the buffer object memory is not accessible through a PCI region.
697 * -EINVAL if the buffer object is currently not mappable.
701 extern int ttm_bo_pci_offset(struct ttm_bo_device *bdev,
702 struct ttm_mem_reg *mem,
703 unsigned long *bus_base,
704 unsigned long *bus_offset,
705 unsigned long *bus_size);
707 extern int ttm_mem_io_reserve(struct ttm_bo_device *bdev,
708 struct ttm_mem_reg *mem);
709 extern void ttm_mem_io_free(struct ttm_bo_device *bdev,
710 struct ttm_mem_reg *mem);
712 extern void ttm_bo_global_release(struct drm_global_reference *ref);
713 extern int ttm_bo_global_init(struct drm_global_reference *ref);
715 extern int ttm_bo_device_release(struct ttm_bo_device *bdev);
720 * @bdev: A pointer to a struct ttm_bo_device to initialize.
721 * @mem_global: A pointer to an initialized struct ttm_mem_global.
722 * @driver: A pointer to a struct ttm_bo_driver set up by the caller.
723 * @file_page_offset: Offset into the device address space that is available
724 * for buffer data. This ensures compatibility with other users of the
727 * Initializes a struct ttm_bo_device:
731 extern int ttm_bo_device_init(struct ttm_bo_device *bdev,
732 struct ttm_bo_global *glob,
733 struct ttm_bo_driver *driver,
734 uint64_t file_page_offset, bool need_dma32);
737 * ttm_bo_unmap_virtual
739 * @bo: tear down the virtual mappings for this BO
741 extern void ttm_bo_unmap_virtual(struct ttm_buffer_object *bo);
746 * @bo: A pointer to a struct ttm_buffer_object.
747 * @interruptible: Sleep interruptible if waiting.
748 * @no_wait: Don't sleep while trying to reserve, rather return -EBUSY.
749 * @use_sequence: If @bo is already reserved, Only sleep waiting for
750 * it to become unreserved if @sequence < (@bo)->sequence.
752 * Locks a buffer object for validation. (Or prevents other processes from
753 * locking it for validation) and removes it from lru lists, while taking
754 * a number of measures to prevent deadlocks.
756 * Deadlocks may occur when two processes try to reserve multiple buffers in
757 * different order, either by will or as a result of a buffer being evicted
758 * to make room for a buffer already reserved. (Buffers are reserved before
759 * they are evicted). The following algorithm prevents such deadlocks from
761 * 1) Buffers are reserved with the lru spinlock held. Upon successful
762 * reservation they are removed from the lru list. This stops a reserved buffer
763 * from being evicted. However the lru spinlock is released between the time
764 * a buffer is selected for eviction and the time it is reserved.
765 * Therefore a check is made when a buffer is reserved for eviction, that it
766 * is still the first buffer in the lru list, before it is removed from the
767 * list. @check_lru == 1 forces this check. If it fails, the function returns
768 * -EINVAL, and the caller should then choose a new buffer to evict and repeat
770 * 2) Processes attempting to reserve multiple buffers other than for eviction,
771 * (typically execbuf), should first obtain a unique 32-bit
772 * validation sequence number,
773 * and call this function with @use_sequence == 1 and @sequence == the unique
774 * sequence number. If upon call of this function, the buffer object is already
775 * reserved, the validation sequence is checked against the validation
776 * sequence of the process currently reserving the buffer,
777 * and if the current validation sequence is greater than that of the process
778 * holding the reservation, the function returns -EAGAIN. Otherwise it sleeps
779 * waiting for the buffer to become unreserved, after which it retries
781 * The caller should, when receiving an -EAGAIN error
782 * release all its buffer reservations, wait for @bo to become unreserved, and
783 * then rerun the validation with the same validation sequence. This procedure
784 * will always guarantee that the process with the lowest validation sequence
785 * will eventually succeed, preventing both deadlocks and starvation.
788 * -EAGAIN: The reservation may cause a deadlock.
789 * Release all buffer reservations, wait for @bo to become unreserved and
790 * try again. (only if use_sequence == 1).
791 * -ERESTARTSYS: A wait for the buffer to become unreserved was interrupted by
792 * a signal. Release all buffer reservations and return to user-space.
794 extern int ttm_bo_reserve(struct ttm_buffer_object *bo,
796 bool no_wait, bool use_sequence, uint32_t sequence);
801 * @bo: A pointer to a struct ttm_buffer_object.
803 * Unreserve a previous reservation of @bo.
805 extern void ttm_bo_unreserve(struct ttm_buffer_object *bo);
808 * ttm_bo_wait_unreserved
810 * @bo: A pointer to a struct ttm_buffer_object.
812 * Wait for a struct ttm_buffer_object to become unreserved.
813 * This is typically used in the execbuf code to relax cpu-usage when
814 * a potential deadlock condition backoff.
816 extern int ttm_bo_wait_unreserved(struct ttm_buffer_object *bo,
826 * @bo: A pointer to a struct ttm_buffer_object.
827 * @evict: 1: This is an eviction. Don't try to pipeline.
828 * @no_wait_reserve: Return immediately if other buffers are busy.
829 * @no_wait_gpu: Return immediately if the GPU is busy.
830 * @new_mem: struct ttm_mem_reg indicating where to move.
832 * Optimized move function for a buffer object with both old and
833 * new placement backed by a TTM. The function will, if successful,
834 * free any old aperture space, and set (@new_mem)->mm_node to NULL,
835 * and update the (@bo)->mem placement flags. If unsuccessful, the old
836 * data remains untouched, and it's up to the caller to free the
837 * memory space indicated by @new_mem.
842 extern int ttm_bo_move_ttm(struct ttm_buffer_object *bo,
843 bool evict, bool no_wait_reserve,
844 bool no_wait_gpu, struct ttm_mem_reg *new_mem);
849 * @bo: A pointer to a struct ttm_buffer_object.
850 * @evict: 1: This is an eviction. Don't try to pipeline.
851 * @no_wait_reserve: Return immediately if other buffers are busy.
852 * @no_wait_gpu: Return immediately if the GPU is busy.
853 * @new_mem: struct ttm_mem_reg indicating where to move.
855 * Fallback move function for a mappable buffer object in mappable memory.
856 * The function will, if successful,
857 * free any old aperture space, and set (@new_mem)->mm_node to NULL,
858 * and update the (@bo)->mem placement flags. If unsuccessful, the old
859 * data remains untouched, and it's up to the caller to free the
860 * memory space indicated by @new_mem.
865 extern int ttm_bo_move_memcpy(struct ttm_buffer_object *bo,
866 bool evict, bool no_wait_reserve,
867 bool no_wait_gpu, struct ttm_mem_reg *new_mem);
870 * ttm_bo_free_old_node
872 * @bo: A pointer to a struct ttm_buffer_object.
874 * Utility function to free an old placement after a successful move.
876 extern void ttm_bo_free_old_node(struct ttm_buffer_object *bo);
879 * ttm_bo_move_accel_cleanup.
881 * @bo: A pointer to a struct ttm_buffer_object.
882 * @sync_obj: A sync object that signals when moving is complete.
883 * @sync_obj_arg: An argument to pass to the sync object idle / wait
885 * @evict: This is an evict move. Don't return until the buffer is idle.
886 * @no_wait_reserve: Return immediately if other buffers are busy.
887 * @no_wait_gpu: Return immediately if the GPU is busy.
888 * @new_mem: struct ttm_mem_reg indicating where to move.
890 * Accelerated move function to be called when an accelerated move
891 * has been scheduled. The function will create a new temporary buffer object
892 * representing the old placement, and put the sync object on both buffer
893 * objects. After that the newly created buffer object is unref'd to be
894 * destroyed when the move is complete. This will help pipeline
898 extern int ttm_bo_move_accel_cleanup(struct ttm_buffer_object *bo,
901 bool evict, bool no_wait_reserve,
903 struct ttm_mem_reg *new_mem);
907 * @c_state: Caching state.
908 * @tmp: Page protection flag for a normal, cached mapping.
910 * Utility function that returns the pgprot_t that should be used for
911 * setting up a PTE with the caching model indicated by @c_state.
913 extern pgprot_t ttm_io_prot(uint32_t caching_flags, pgprot_t tmp);
915 extern const struct ttm_mem_type_manager_func ttm_bo_manager_func;
917 #if (defined(CONFIG_AGP) || (defined(CONFIG_AGP_MODULE) && defined(MODULE)))
919 #include <linux/agp_backend.h>
922 * ttm_agp_backend_init
924 * @bdev: Pointer to a struct ttm_bo_device.
925 * @bridge: The agp bridge this device is sitting on.
927 * Create a TTM backend that uses the indicated AGP bridge as an aperture
928 * for TT memory. This function uses the linux agpgart interface to
929 * bind and unbind memory backing a ttm_tt.
931 extern struct ttm_backend *ttm_agp_backend_init(struct ttm_bo_device *bdev,
932 struct agp_bridge_data *bridge);