~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

TOMOYO Linux Cross Reference
Linux/include/drm/ttm/ttm_bo_driver.h

Version: ~ [ linux-5.10-rc1 ] ~ [ linux-5.9.1 ] ~ [ linux-5.8.16 ] ~ [ linux-5.7.19 ] ~ [ linux-5.6.19 ] ~ [ linux-5.5.19 ] ~ [ linux-5.4.72 ] ~ [ linux-5.3.18 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.152 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.202 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.240 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.240 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.19.8 ] ~ [ linux-3.18.140 ] ~ [ linux-3.17.8 ] ~ [ linux-3.16.85 ] ~ [ linux-3.15.10 ] ~ [ linux-3.14.79 ] ~ [ linux-3.13.11 ] ~ [ linux-3.12.74 ] ~ [ linux-3.11.10 ] ~ [ linux-3.10.108 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  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 #ifndef _TTM_BO_DRIVER_H_
 31 #define _TTM_BO_DRIVER_H_
 32 
 33 #include <drm/drm_mm.h>
 34 #include <drm/drm_vma_manager.h>
 35 #include <linux/workqueue.h>
 36 #include <linux/fs.h>
 37 #include <linux/spinlock.h>
 38 #include <linux/reservation.h>
 39 
 40 #include "ttm_bo_api.h"
 41 #include "ttm_memory.h"
 42 #include "ttm_module.h"
 43 #include "ttm_placement.h"
 44 #include "ttm_tt.h"
 45 
 46 #define TTM_MAX_BO_PRIORITY     4U
 47 
 48 #define TTM_MEMTYPE_FLAG_FIXED         (1 << 0) /* Fixed (on-card) PCI memory */
 49 #define TTM_MEMTYPE_FLAG_MAPPABLE      (1 << 1) /* Memory mappable */
 50 #define TTM_MEMTYPE_FLAG_CMA           (1 << 3) /* Can't map aperture */
 51 
 52 struct ttm_mem_type_manager;
 53 
 54 struct ttm_mem_type_manager_func {
 55         /**
 56          * struct ttm_mem_type_manager member init
 57          *
 58          * @man: Pointer to a memory type manager.
 59          * @p_size: Implementation dependent, but typically the size of the
 60          * range to be managed in pages.
 61          *
 62          * Called to initialize a private range manager. The function is
 63          * expected to initialize the man::priv member.
 64          * Returns 0 on success, negative error code on failure.
 65          */
 66         int  (*init)(struct ttm_mem_type_manager *man, unsigned long p_size);
 67 
 68         /**
 69          * struct ttm_mem_type_manager member takedown
 70          *
 71          * @man: Pointer to a memory type manager.
 72          *
 73          * Called to undo the setup done in init. All allocated resources
 74          * should be freed.
 75          */
 76         int  (*takedown)(struct ttm_mem_type_manager *man);
 77 
 78         /**
 79          * struct ttm_mem_type_manager member get_node
 80          *
 81          * @man: Pointer to a memory type manager.
 82          * @bo: Pointer to the buffer object we're allocating space for.
 83          * @placement: Placement details.
 84          * @flags: Additional placement flags.
 85          * @mem: Pointer to a struct ttm_mem_reg to be filled in.
 86          *
 87          * This function should allocate space in the memory type managed
 88          * by @man. Placement details if
 89          * applicable are given by @placement. If successful,
 90          * @mem::mm_node should be set to a non-null value, and
 91          * @mem::start should be set to a value identifying the beginning
 92          * of the range allocated, and the function should return zero.
 93          * If the memory region accommodate the buffer object, @mem::mm_node
 94          * should be set to NULL, and the function should return 0.
 95          * If a system error occurred, preventing the request to be fulfilled,
 96          * the function should return a negative error code.
 97          *
 98          * Note that @mem::mm_node will only be dereferenced by
 99          * struct ttm_mem_type_manager functions and optionally by the driver,
100          * which has knowledge of the underlying type.
101          *
102          * This function may not be called from within atomic context, so
103          * an implementation can and must use either a mutex or a spinlock to
104          * protect any data structures managing the space.
105          */
106         int  (*get_node)(struct ttm_mem_type_manager *man,
107                          struct ttm_buffer_object *bo,
108                          const struct ttm_place *place,
109                          struct ttm_mem_reg *mem);
110 
111         /**
112          * struct ttm_mem_type_manager member put_node
113          *
114          * @man: Pointer to a memory type manager.
115          * @mem: Pointer to a struct ttm_mem_reg to be filled in.
116          *
117          * This function frees memory type resources previously allocated
118          * and that are identified by @mem::mm_node and @mem::start. May not
119          * be called from within atomic context.
120          */
121         void (*put_node)(struct ttm_mem_type_manager *man,
122                          struct ttm_mem_reg *mem);
123 
124         /**
125          * struct ttm_mem_type_manager member debug
126          *
127          * @man: Pointer to a memory type manager.
128          * @printer: Prefix to be used in printout to identify the caller.
129          *
130          * This function is called to print out the state of the memory
131          * type manager to aid debugging of out-of-memory conditions.
132          * It may not be called from within atomic context.
133          */
134         void (*debug)(struct ttm_mem_type_manager *man,
135                       struct drm_printer *printer);
136 };
137 
138 /**
139  * struct ttm_mem_type_manager
140  *
141  * @has_type: The memory type has been initialized.
142  * @use_type: The memory type is enabled.
143  * @flags: TTM_MEMTYPE_XX flags identifying the traits of the memory
144  * managed by this memory type.
145  * @gpu_offset: If used, the GPU offset of the first managed page of
146  * fixed memory or the first managed location in an aperture.
147  * @size: Size of the managed region.
148  * @available_caching: A mask of available caching types, TTM_PL_FLAG_XX,
149  * as defined in ttm_placement_common.h
150  * @default_caching: The default caching policy used for a buffer object
151  * placed in this memory type if the user doesn't provide one.
152  * @func: structure pointer implementing the range manager. See above
153  * @priv: Driver private closure for @func.
154  * @io_reserve_mutex: Mutex optionally protecting shared io_reserve structures
155  * @use_io_reserve_lru: Use an lru list to try to unreserve io_mem_regions
156  * reserved by the TTM vm system.
157  * @io_reserve_lru: Optional lru list for unreserving io mem regions.
158  * @io_reserve_fastpath: Only use bdev::driver::io_mem_reserve to obtain
159  * @move_lock: lock for move fence
160  * static information. bdev::driver::io_mem_free is never used.
161  * @lru: The lru list for this memory type.
162  * @move: The fence of the last pipelined move operation.
163  *
164  * This structure is used to identify and manage memory types for a device.
165  * It's set up by the ttm_bo_driver::init_mem_type method.
166  */
167 
168 
169 
170 struct ttm_mem_type_manager {
171         struct ttm_bo_device *bdev;
172 
173         /*
174          * No protection. Constant from start.
175          */
176 
177         bool has_type;
178         bool use_type;
179         uint32_t flags;
180         uint64_t gpu_offset; /* GPU address space is independent of CPU word size */
181         uint64_t size;
182         uint32_t available_caching;
183         uint32_t default_caching;
184         const struct ttm_mem_type_manager_func *func;
185         void *priv;
186         struct mutex io_reserve_mutex;
187         bool use_io_reserve_lru;
188         bool io_reserve_fastpath;
189         spinlock_t move_lock;
190 
191         /*
192          * Protected by @io_reserve_mutex:
193          */
194 
195         struct list_head io_reserve_lru;
196 
197         /*
198          * Protected by the global->lru_lock.
199          */
200 
201         struct list_head lru[TTM_MAX_BO_PRIORITY];
202 
203         /*
204          * Protected by @move_lock.
205          */
206         struct dma_fence *move;
207 };
208 
209 /**
210  * struct ttm_bo_driver
211  *
212  * @create_ttm_backend_entry: Callback to create a struct ttm_backend.
213  * @invalidate_caches: Callback to invalidate read caches when a buffer object
214  * has been evicted.
215  * @init_mem_type: Callback to initialize a struct ttm_mem_type_manager
216  * structure.
217  * @evict_flags: Callback to obtain placement flags when a buffer is evicted.
218  * @move: Callback for a driver to hook in accelerated functions to
219  * move a buffer.
220  * If set to NULL, a potentially slow memcpy() move is used.
221  */
222 
223 struct ttm_bo_driver {
224         /**
225          * ttm_tt_create
226          *
227          * @bo: The buffer object to create the ttm for.
228          * @page_flags: Page flags as identified by TTM_PAGE_FLAG_XX flags.
229          *
230          * Create a struct ttm_tt to back data with system memory pages.
231          * No pages are actually allocated.
232          * Returns:
233          * NULL: Out of memory.
234          */
235         struct ttm_tt *(*ttm_tt_create)(struct ttm_buffer_object *bo,
236                                         uint32_t page_flags);
237 
238         /**
239          * ttm_tt_populate
240          *
241          * @ttm: The struct ttm_tt to contain the backing pages.
242          *
243          * Allocate all backing pages
244          * Returns:
245          * -ENOMEM: Out of memory.
246          */
247         int (*ttm_tt_populate)(struct ttm_tt *ttm,
248                         struct ttm_operation_ctx *ctx);
249 
250         /**
251          * ttm_tt_unpopulate
252          *
253          * @ttm: The struct ttm_tt to contain the backing pages.
254          *
255          * Free all backing page
256          */
257         void (*ttm_tt_unpopulate)(struct ttm_tt *ttm);
258 
259         /**
260          * struct ttm_bo_driver member invalidate_caches
261          *
262          * @bdev: the buffer object device.
263          * @flags: new placement of the rebound buffer object.
264          *
265          * A previosly evicted buffer has been rebound in a
266          * potentially new location. Tell the driver that it might
267          * consider invalidating read (texture) caches on the next command
268          * submission as a consequence.
269          */
270 
271         int (*invalidate_caches)(struct ttm_bo_device *bdev, uint32_t flags);
272         int (*init_mem_type)(struct ttm_bo_device *bdev, uint32_t type,
273                              struct ttm_mem_type_manager *man);
274 
275         /**
276          * struct ttm_bo_driver member eviction_valuable
277          *
278          * @bo: the buffer object to be evicted
279          * @place: placement we need room for
280          *
281          * Check with the driver if it is valuable to evict a BO to make room
282          * for a certain placement.
283          */
284         bool (*eviction_valuable)(struct ttm_buffer_object *bo,
285                                   const struct ttm_place *place);
286         /**
287          * struct ttm_bo_driver member evict_flags:
288          *
289          * @bo: the buffer object to be evicted
290          *
291          * Return the bo flags for a buffer which is not mapped to the hardware.
292          * These will be placed in proposed_flags so that when the move is
293          * finished, they'll end up in bo->mem.flags
294          */
295 
296         void (*evict_flags)(struct ttm_buffer_object *bo,
297                             struct ttm_placement *placement);
298 
299         /**
300          * struct ttm_bo_driver member move:
301          *
302          * @bo: the buffer to move
303          * @evict: whether this motion is evicting the buffer from
304          * the graphics address space
305          * @ctx: context for this move with parameters
306          * @new_mem: the new memory region receiving the buffer
307          *
308          * Move a buffer between two memory regions.
309          */
310         int (*move)(struct ttm_buffer_object *bo, bool evict,
311                     struct ttm_operation_ctx *ctx,
312                     struct ttm_mem_reg *new_mem);
313 
314         /**
315          * struct ttm_bo_driver_member verify_access
316          *
317          * @bo: Pointer to a buffer object.
318          * @filp: Pointer to a struct file trying to access the object.
319          *
320          * Called from the map / write / read methods to verify that the
321          * caller is permitted to access the buffer object.
322          * This member may be set to NULL, which will refuse this kind of
323          * access for all buffer objects.
324          * This function should return 0 if access is granted, -EPERM otherwise.
325          */
326         int (*verify_access)(struct ttm_buffer_object *bo,
327                              struct file *filp);
328 
329         /**
330          * Hook to notify driver about a driver move so it
331          * can do tiling things and book-keeping.
332          *
333          * @evict: whether this move is evicting the buffer from the graphics
334          * address space
335          */
336         void (*move_notify)(struct ttm_buffer_object *bo,
337                             bool evict,
338                             struct ttm_mem_reg *new_mem);
339         /* notify the driver we are taking a fault on this BO
340          * and have reserved it */
341         int (*fault_reserve_notify)(struct ttm_buffer_object *bo);
342 
343         /**
344          * notify the driver that we're about to swap out this bo
345          */
346         void (*swap_notify)(struct ttm_buffer_object *bo);
347 
348         /**
349          * Driver callback on when mapping io memory (for bo_move_memcpy
350          * for instance). TTM will take care to call io_mem_free whenever
351          * the mapping is not use anymore. io_mem_reserve & io_mem_free
352          * are balanced.
353          */
354         int (*io_mem_reserve)(struct ttm_bo_device *bdev,
355                               struct ttm_mem_reg *mem);
356         void (*io_mem_free)(struct ttm_bo_device *bdev,
357                             struct ttm_mem_reg *mem);
358 
359         /**
360          * Return the pfn for a given page_offset inside the BO.
361          *
362          * @bo: the BO to look up the pfn for
363          * @page_offset: the offset to look up
364          */
365         unsigned long (*io_mem_pfn)(struct ttm_buffer_object *bo,
366                                     unsigned long page_offset);
367 
368         /**
369          * Read/write memory buffers for ptrace access
370          *
371          * @bo: the BO to access
372          * @offset: the offset from the start of the BO
373          * @buf: pointer to source/destination buffer
374          * @len: number of bytes to copy
375          * @write: whether to read (0) from or write (non-0) to BO
376          *
377          * If successful, this function should return the number of
378          * bytes copied, -EIO otherwise. If the number of bytes
379          * returned is < len, the function may be called again with
380          * the remainder of the buffer to copy.
381          */
382         int (*access_memory)(struct ttm_buffer_object *bo, unsigned long offset,
383                              void *buf, int len, int write);
384 
385         /**
386          * struct ttm_bo_driver member del_from_lru_notify
387          *
388          * @bo: the buffer object deleted from lru
389          *
390          * notify driver that a BO was deleted from LRU.
391          */
392         void (*del_from_lru_notify)(struct ttm_buffer_object *bo);
393 };
394 
395 /**
396  * struct ttm_bo_global - Buffer object driver global data.
397  *
398  * @mem_glob: Pointer to a struct ttm_mem_global object for accounting.
399  * @dummy_read_page: Pointer to a dummy page used for mapping requests
400  * of unpopulated pages.
401  * @shrink: A shrink callback object used for buffer object swap.
402  * @device_list_mutex: Mutex protecting the device list.
403  * This mutex is held while traversing the device list for pm options.
404  * @lru_lock: Spinlock protecting the bo subsystem lru lists.
405  * @device_list: List of buffer object devices.
406  * @swap_lru: Lru list of buffer objects used for swapping.
407  */
408 
409 extern struct ttm_bo_global {
410 
411         /**
412          * Constant after init.
413          */
414 
415         struct kobject kobj;
416         struct ttm_mem_global *mem_glob;
417         struct page *dummy_read_page;
418         spinlock_t lru_lock;
419 
420         /**
421          * Protected by ttm_global_mutex.
422          */
423         struct list_head device_list;
424 
425         /**
426          * Protected by the lru_lock.
427          */
428         struct list_head swap_lru[TTM_MAX_BO_PRIORITY];
429 
430         /**
431          * Internal protection.
432          */
433         atomic_t bo_count;
434 } ttm_bo_glob;
435 
436 
437 #define TTM_NUM_MEM_TYPES 8
438 
439 /**
440  * struct ttm_bo_device - Buffer object driver device-specific data.
441  *
442  * @driver: Pointer to a struct ttm_bo_driver struct setup by the driver.
443  * @man: An array of mem_type_managers.
444  * @vma_manager: Address space manager
445  * lru_lock: Spinlock that protects the buffer+device lru lists and
446  * ddestroy lists.
447  * @dev_mapping: A pointer to the struct address_space representing the
448  * device address space.
449  * @wq: Work queue structure for the delayed delete workqueue.
450  * @no_retry: Don't retry allocation if it fails
451  *
452  */
453 
454 struct ttm_bo_device {
455 
456         /*
457          * Constant after bo device init / atomic.
458          */
459         struct list_head device_list;
460         struct ttm_bo_global *glob;
461         struct ttm_bo_driver *driver;
462         struct ttm_mem_type_manager man[TTM_NUM_MEM_TYPES];
463 
464         /*
465          * Protected by internal locks.
466          */
467         struct drm_vma_offset_manager vma_manager;
468 
469         /*
470          * Protected by the global:lru lock.
471          */
472         struct list_head ddestroy;
473 
474         /*
475          * Protected by load / firstopen / lastclose /unload sync.
476          */
477 
478         struct address_space *dev_mapping;
479 
480         /*
481          * Internal protection.
482          */
483 
484         struct delayed_work wq;
485 
486         bool need_dma32;
487 
488         bool no_retry;
489 };
490 
491 /**
492  * struct ttm_lru_bulk_move_pos
493  *
494  * @first: first BO in the bulk move range
495  * @last: last BO in the bulk move range
496  *
497  * Positions for a lru bulk move.
498  */
499 struct ttm_lru_bulk_move_pos {
500         struct ttm_buffer_object *first;
501         struct ttm_buffer_object *last;
502 };
503 
504 /**
505  * struct ttm_lru_bulk_move
506  *
507  * @tt: first/last lru entry for BOs in the TT domain
508  * @vram: first/last lru entry for BOs in the VRAM domain
509  * @swap: first/last lru entry for BOs on the swap list
510  *
511  * Helper structure for bulk moves on the LRU list.
512  */
513 struct ttm_lru_bulk_move {
514         struct ttm_lru_bulk_move_pos tt[TTM_MAX_BO_PRIORITY];
515         struct ttm_lru_bulk_move_pos vram[TTM_MAX_BO_PRIORITY];
516         struct ttm_lru_bulk_move_pos swap[TTM_MAX_BO_PRIORITY];
517 };
518 
519 /**
520  * ttm_flag_masked
521  *
522  * @old: Pointer to the result and original value.
523  * @new: New value of bits.
524  * @mask: Mask of bits to change.
525  *
526  * Convenience function to change a number of bits identified by a mask.
527  */
528 
529 static inline uint32_t
530 ttm_flag_masked(uint32_t *old, uint32_t new, uint32_t mask)
531 {
532         *old ^= (*old ^ new) & mask;
533         return *old;
534 }
535 
536 /*
537  * ttm_bo.c
538  */
539 
540 /**
541  * ttm_mem_reg_is_pci
542  *
543  * @bdev: Pointer to a struct ttm_bo_device.
544  * @mem: A valid struct ttm_mem_reg.
545  *
546  * Returns true if the memory described by @mem is PCI memory,
547  * false otherwise.
548  */
549 bool ttm_mem_reg_is_pci(struct ttm_bo_device *bdev, struct ttm_mem_reg *mem);
550 
551 /**
552  * ttm_bo_mem_space
553  *
554  * @bo: Pointer to a struct ttm_buffer_object. the data of which
555  * we want to allocate space for.
556  * @proposed_placement: Proposed new placement for the buffer object.
557  * @mem: A struct ttm_mem_reg.
558  * @interruptible: Sleep interruptible when sliping.
559  * @no_wait_gpu: Return immediately if the GPU is busy.
560  *
561  * Allocate memory space for the buffer object pointed to by @bo, using
562  * the placement flags in @mem, potentially evicting other idle buffer objects.
563  * This function may sleep while waiting for space to become available.
564  * Returns:
565  * -EBUSY: No space available (only if no_wait == 1).
566  * -ENOMEM: Could not allocate memory for the buffer object, either due to
567  * fragmentation or concurrent allocators.
568  * -ERESTARTSYS: An interruptible sleep was interrupted by a signal.
569  */
570 int ttm_bo_mem_space(struct ttm_buffer_object *bo,
571                      struct ttm_placement *placement,
572                      struct ttm_mem_reg *mem,
573                      struct ttm_operation_ctx *ctx);
574 
575 void ttm_bo_mem_put(struct ttm_buffer_object *bo, struct ttm_mem_reg *mem);
576 void ttm_bo_mem_put_locked(struct ttm_buffer_object *bo,
577                            struct ttm_mem_reg *mem);
578 
579 int ttm_bo_device_release(struct ttm_bo_device *bdev);
580 
581 /**
582  * ttm_bo_device_init
583  *
584  * @bdev: A pointer to a struct ttm_bo_device to initialize.
585  * @glob: A pointer to an initialized struct ttm_bo_global.
586  * @driver: A pointer to a struct ttm_bo_driver set up by the caller.
587  * @mapping: The address space to use for this bo.
588  * @file_page_offset: Offset into the device address space that is available
589  * for buffer data. This ensures compatibility with other users of the
590  * address space.
591  *
592  * Initializes a struct ttm_bo_device:
593  * Returns:
594  * !0: Failure.
595  */
596 int ttm_bo_device_init(struct ttm_bo_device *bdev,
597                        struct ttm_bo_driver *driver,
598                        struct address_space *mapping,
599                        bool need_dma32);
600 
601 /**
602  * ttm_bo_unmap_virtual
603  *
604  * @bo: tear down the virtual mappings for this BO
605  */
606 void ttm_bo_unmap_virtual(struct ttm_buffer_object *bo);
607 
608 /**
609  * ttm_bo_unmap_virtual
610  *
611  * @bo: tear down the virtual mappings for this BO
612  *
613  * The caller must take ttm_mem_io_lock before calling this function.
614  */
615 void ttm_bo_unmap_virtual_locked(struct ttm_buffer_object *bo);
616 
617 int ttm_mem_io_reserve_vm(struct ttm_buffer_object *bo);
618 void ttm_mem_io_free_vm(struct ttm_buffer_object *bo);
619 int ttm_mem_io_lock(struct ttm_mem_type_manager *man, bool interruptible);
620 void ttm_mem_io_unlock(struct ttm_mem_type_manager *man);
621 
622 void ttm_bo_del_sub_from_lru(struct ttm_buffer_object *bo);
623 void ttm_bo_add_to_lru(struct ttm_buffer_object *bo);
624 
625 /**
626  * __ttm_bo_reserve:
627  *
628  * @bo: A pointer to a struct ttm_buffer_object.
629  * @interruptible: Sleep interruptible if waiting.
630  * @no_wait: Don't sleep while trying to reserve, rather return -EBUSY.
631  * @ticket: ticket used to acquire the ww_mutex.
632  *
633  * Will not remove reserved buffers from the lru lists.
634  * Otherwise identical to ttm_bo_reserve.
635  *
636  * Returns:
637  * -EDEADLK: The reservation may cause a deadlock.
638  * Release all buffer reservations, wait for @bo to become unreserved and
639  * try again. (only if use_sequence == 1).
640  * -ERESTARTSYS: A wait for the buffer to become unreserved was interrupted by
641  * a signal. Release all buffer reservations and return to user-space.
642  * -EBUSY: The function needed to sleep, but @no_wait was true
643  * -EALREADY: Bo already reserved using @ticket. This error code will only
644  * be returned if @use_ticket is set to true.
645  */
646 static inline int __ttm_bo_reserve(struct ttm_buffer_object *bo,
647                                    bool interruptible, bool no_wait,
648                                    struct ww_acquire_ctx *ticket)
649 {
650         int ret = 0;
651 
652         if (no_wait) {
653                 bool success;
654                 if (WARN_ON(ticket))
655                         return -EBUSY;
656 
657                 success = reservation_object_trylock(bo->resv);
658                 return success ? 0 : -EBUSY;
659         }
660 
661         if (interruptible)
662                 ret = reservation_object_lock_interruptible(bo->resv, ticket);
663         else
664                 ret = reservation_object_lock(bo->resv, ticket);
665         if (ret == -EINTR)
666                 return -ERESTARTSYS;
667         return ret;
668 }
669 
670 /**
671  * ttm_bo_reserve:
672  *
673  * @bo: A pointer to a struct ttm_buffer_object.
674  * @interruptible: Sleep interruptible if waiting.
675  * @no_wait: Don't sleep while trying to reserve, rather return -EBUSY.
676  * @ticket: ticket used to acquire the ww_mutex.
677  *
678  * Locks a buffer object for validation. (Or prevents other processes from
679  * locking it for validation) and removes it from lru lists, while taking
680  * a number of measures to prevent deadlocks.
681  *
682  * Deadlocks may occur when two processes try to reserve multiple buffers in
683  * different order, either by will or as a result of a buffer being evicted
684  * to make room for a buffer already reserved. (Buffers are reserved before
685  * they are evicted). The following algorithm prevents such deadlocks from
686  * occurring:
687  * Processes attempting to reserve multiple buffers other than for eviction,
688  * (typically execbuf), should first obtain a unique 32-bit
689  * validation sequence number,
690  * and call this function with @use_ticket == 1 and @ticket->stamp == the unique
691  * sequence number. If upon call of this function, the buffer object is already
692  * reserved, the validation sequence is checked against the validation
693  * sequence of the process currently reserving the buffer,
694  * and if the current validation sequence is greater than that of the process
695  * holding the reservation, the function returns -EDEADLK. Otherwise it sleeps
696  * waiting for the buffer to become unreserved, after which it retries
697  * reserving.
698  * The caller should, when receiving an -EDEADLK error
699  * release all its buffer reservations, wait for @bo to become unreserved, and
700  * then rerun the validation with the same validation sequence. This procedure
701  * will always guarantee that the process with the lowest validation sequence
702  * will eventually succeed, preventing both deadlocks and starvation.
703  *
704  * Returns:
705  * -EDEADLK: The reservation may cause a deadlock.
706  * Release all buffer reservations, wait for @bo to become unreserved and
707  * try again. (only if use_sequence == 1).
708  * -ERESTARTSYS: A wait for the buffer to become unreserved was interrupted by
709  * a signal. Release all buffer reservations and return to user-space.
710  * -EBUSY: The function needed to sleep, but @no_wait was true
711  * -EALREADY: Bo already reserved using @ticket. This error code will only
712  * be returned if @use_ticket is set to true.
713  */
714 static inline int ttm_bo_reserve(struct ttm_buffer_object *bo,
715                                  bool interruptible, bool no_wait,
716                                  struct ww_acquire_ctx *ticket)
717 {
718         int ret;
719 
720         WARN_ON(!kref_read(&bo->kref));
721 
722         ret = __ttm_bo_reserve(bo, interruptible, no_wait, ticket);
723         if (likely(ret == 0))
724                 ttm_bo_del_sub_from_lru(bo);
725 
726         return ret;
727 }
728 
729 /**
730  * ttm_bo_reserve_slowpath:
731  * @bo: A pointer to a struct ttm_buffer_object.
732  * @interruptible: Sleep interruptible if waiting.
733  * @sequence: Set (@bo)->sequence to this value after lock
734  *
735  * This is called after ttm_bo_reserve returns -EAGAIN and we backed off
736  * from all our other reservations. Because there are no other reservations
737  * held by us, this function cannot deadlock any more.
738  */
739 static inline int ttm_bo_reserve_slowpath(struct ttm_buffer_object *bo,
740                                           bool interruptible,
741                                           struct ww_acquire_ctx *ticket)
742 {
743         int ret = 0;
744 
745         WARN_ON(!kref_read(&bo->kref));
746 
747         if (interruptible)
748                 ret = ww_mutex_lock_slow_interruptible(&bo->resv->lock,
749                                                        ticket);
750         else
751                 ww_mutex_lock_slow(&bo->resv->lock, ticket);
752 
753         if (likely(ret == 0))
754                 ttm_bo_del_sub_from_lru(bo);
755         else if (ret == -EINTR)
756                 ret = -ERESTARTSYS;
757 
758         return ret;
759 }
760 
761 /**
762  * ttm_bo_unreserve
763  *
764  * @bo: A pointer to a struct ttm_buffer_object.
765  *
766  * Unreserve a previous reservation of @bo.
767  */
768 static inline void ttm_bo_unreserve(struct ttm_buffer_object *bo)
769 {
770         spin_lock(&bo->bdev->glob->lru_lock);
771         if (list_empty(&bo->lru))
772                 ttm_bo_add_to_lru(bo);
773         else
774                 ttm_bo_move_to_lru_tail(bo, NULL);
775         spin_unlock(&bo->bdev->glob->lru_lock);
776         reservation_object_unlock(bo->resv);
777 }
778 
779 /*
780  * ttm_bo_util.c
781  */
782 
783 int ttm_mem_io_reserve(struct ttm_bo_device *bdev,
784                        struct ttm_mem_reg *mem);
785 void ttm_mem_io_free(struct ttm_bo_device *bdev,
786                      struct ttm_mem_reg *mem);
787 /**
788  * ttm_bo_move_ttm
789  *
790  * @bo: A pointer to a struct ttm_buffer_object.
791  * @interruptible: Sleep interruptible if waiting.
792  * @no_wait_gpu: Return immediately if the GPU is busy.
793  * @new_mem: struct ttm_mem_reg indicating where to move.
794  *
795  * Optimized move function for a buffer object with both old and
796  * new placement backed by a TTM. The function will, if successful,
797  * free any old aperture space, and set (@new_mem)->mm_node to NULL,
798  * and update the (@bo)->mem placement flags. If unsuccessful, the old
799  * data remains untouched, and it's up to the caller to free the
800  * memory space indicated by @new_mem.
801  * Returns:
802  * !0: Failure.
803  */
804 
805 int ttm_bo_move_ttm(struct ttm_buffer_object *bo,
806                     struct ttm_operation_ctx *ctx,
807                     struct ttm_mem_reg *new_mem);
808 
809 /**
810  * ttm_bo_move_memcpy
811  *
812  * @bo: A pointer to a struct ttm_buffer_object.
813  * @interruptible: Sleep interruptible if waiting.
814  * @no_wait_gpu: Return immediately if the GPU is busy.
815  * @new_mem: struct ttm_mem_reg indicating where to move.
816  *
817  * Fallback move function for a mappable buffer object in mappable memory.
818  * The function will, if successful,
819  * free any old aperture space, and set (@new_mem)->mm_node to NULL,
820  * and update the (@bo)->mem placement flags. If unsuccessful, the old
821  * data remains untouched, and it's up to the caller to free the
822  * memory space indicated by @new_mem.
823  * Returns:
824  * !0: Failure.
825  */
826 
827 int ttm_bo_move_memcpy(struct ttm_buffer_object *bo,
828                        struct ttm_operation_ctx *ctx,
829                        struct ttm_mem_reg *new_mem);
830 
831 /**
832  * ttm_bo_free_old_node
833  *
834  * @bo: A pointer to a struct ttm_buffer_object.
835  *
836  * Utility function to free an old placement after a successful move.
837  */
838 void ttm_bo_free_old_node(struct ttm_buffer_object *bo);
839 
840 /**
841  * ttm_bo_move_accel_cleanup.
842  *
843  * @bo: A pointer to a struct ttm_buffer_object.
844  * @fence: A fence object that signals when moving is complete.
845  * @evict: This is an evict move. Don't return until the buffer is idle.
846  * @new_mem: struct ttm_mem_reg indicating where to move.
847  *
848  * Accelerated move function to be called when an accelerated move
849  * has been scheduled. The function will create a new temporary buffer object
850  * representing the old placement, and put the sync object on both buffer
851  * objects. After that the newly created buffer object is unref'd to be
852  * destroyed when the move is complete. This will help pipeline
853  * buffer moves.
854  */
855 int ttm_bo_move_accel_cleanup(struct ttm_buffer_object *bo,
856                               struct dma_fence *fence, bool evict,
857                               struct ttm_mem_reg *new_mem);
858 
859 /**
860  * ttm_bo_pipeline_move.
861  *
862  * @bo: A pointer to a struct ttm_buffer_object.
863  * @fence: A fence object that signals when moving is complete.
864  * @evict: This is an evict move. Don't return until the buffer is idle.
865  * @new_mem: struct ttm_mem_reg indicating where to move.
866  *
867  * Function for pipelining accelerated moves. Either free the memory
868  * immediately or hang it on a temporary buffer object.
869  */
870 int ttm_bo_pipeline_move(struct ttm_buffer_object *bo,
871                          struct dma_fence *fence, bool evict,
872                          struct ttm_mem_reg *new_mem);
873 
874 /**
875  * ttm_bo_pipeline_gutting.
876  *
877  * @bo: A pointer to a struct ttm_buffer_object.
878  *
879  * Pipelined gutting a BO of its backing store.
880  */
881 int ttm_bo_pipeline_gutting(struct ttm_buffer_object *bo);
882 
883 /**
884  * ttm_io_prot
885  *
886  * @c_state: Caching state.
887  * @tmp: Page protection flag for a normal, cached mapping.
888  *
889  * Utility function that returns the pgprot_t that should be used for
890  * setting up a PTE with the caching model indicated by @c_state.
891  */
892 pgprot_t ttm_io_prot(uint32_t caching_flags, pgprot_t tmp);
893 
894 extern const struct ttm_mem_type_manager_func ttm_bo_manager_func;
895 
896 #endif
897 

~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

kernel.org | git.kernel.org | LWN.net | Project Home | Wiki (Japanese) | Wiki (English) | SVN repository | Mail admin

Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.

osdn.jp