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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_hashtab.h"
35#include <linux/kref.h>
36#include <linux/list.h>
37#include <linux/wait.h>
38#include <linux/mutex.h>
39#include <linux/mm.h>
40#include <linux/rbtree.h>
41#include <linux/bitmap.h>
42
43struct ttm_bo_device;
44
45struct 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 preferred placements
54 * @placement: preferred placements
55 * @num_busy_placement: number of preferred placements when need to evict buffer
56 * @busy_placement: preferred placements when need to evict buffer
57 *
58 * Structure indicating the placement you request for an object.
59 */
60struct 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 * struct ttm_bus_placement
71 *
72 * @addr: mapped virtual address
73 * @base: bus base address
74 * @is_iomem: is this io memory ?
75 * @size: size in byte
76 * @offset: offset from the base address
77 * @io_reserved_vm: The VM system has a refcount in @io_reserved_count
78 * @io_reserved_count: Refcounting the numbers of callers to ttm_mem_io_reserve
79 *
80 * Structure indicating the bus placement of an object.
81 */
82struct ttm_bus_placement {
83 void *addr;
84 unsigned long base;
85 unsigned long size;
86 unsigned long offset;
87 bool is_iomem;
88 bool io_reserved_vm;
89 uint64_t io_reserved_count;
90};
91
92
93/**
94 * struct ttm_mem_reg
95 *
96 * @mm_node: Memory manager node.
97 * @size: Requested size of memory region.
98 * @num_pages: Actual size of memory region in pages.
99 * @page_alignment: Page alignment.
100 * @placement: Placement flags.
101 * @bus: Placement on io bus accessible to the CPU
102 *
103 * Structure indicating the placement and space resources used by a
104 * buffer object.
105 */
106
107struct ttm_mem_reg {
108 void *mm_node;
109 unsigned long start;
110 unsigned long size;
111 unsigned long num_pages;
112 uint32_t page_alignment;
113 uint32_t mem_type;
114 uint32_t placement;
115 struct ttm_bus_placement bus;
116};
117
118/**
119 * enum ttm_bo_type
120 *
121 * @ttm_bo_type_device: These are 'normal' buffers that can
122 * be mmapped by user space. Each of these bos occupy a slot in the
123 * device address space, that can be used for normal vm operations.
124 *
125 * @ttm_bo_type_user: These are user-space memory areas that are made
126 * available to the GPU by mapping the buffer pages into the GPU aperture
127 * space. These buffers cannot be mmaped from the device address space.
128 *
129 * @ttm_bo_type_kernel: These buffers are like ttm_bo_type_device buffers,
130 * but they cannot be accessed from user-space. For kernel-only use.
131 */
132
133enum ttm_bo_type {
134 ttm_bo_type_device,
135 ttm_bo_type_user,
136 ttm_bo_type_kernel
137};
138
139struct ttm_tt;
140
141/**
142 * struct ttm_buffer_object
143 *
144 * @bdev: Pointer to the buffer object device structure.
145 * @buffer_start: The virtual user-space start address of ttm_bo_type_user
146 * buffers.
147 * @type: The bo type.
148 * @destroy: Destruction function. If NULL, kfree is used.
149 * @num_pages: Actual number of pages.
150 * @addr_space_offset: Address space offset.
151 * @acc_size: Accounted size for this object.
152 * @kref: Reference count of this buffer object. When this refcount reaches
153 * zero, the object is put on the delayed delete list.
154 * @list_kref: List reference count of this buffer object. This member is
155 * used to avoid destruction while the buffer object is still on a list.
156 * Lru lists may keep one refcount, the delayed delete list, and kref != 0
157 * keeps one refcount. When this refcount reaches zero,
158 * the object is destroyed.
159 * @event_queue: Queue for processes waiting on buffer object status change.
160 * @mem: structure describing current placement.
161 * @persistent_swap_storage: Usually the swap storage is deleted for buffers
162 * pinned in physical memory. If this behaviour is not desired, this member
163 * holds a pointer to a persistent shmem object.
164 * @ttm: TTM structure holding system pages.
165 * @evicted: Whether the object was evicted without user-space knowing.
166 * @cpu_writes: For synchronization. Number of cpu writers.
167 * @lru: List head for the lru list.
168 * @ddestroy: List head for the delayed destroy list.
169 * @swap: List head for swap LRU list.
170 * @val_seq: Sequence of the validation holding the @reserved lock.
171 * Used to avoid starvation when many processes compete to validate the
172 * buffer. This member is protected by the bo_device::lru_lock.
173 * @seq_valid: The value of @val_seq is valid. This value is protected by
174 * the bo_device::lru_lock.
175 * @reserved: Deadlock-free lock used for synchronization state transitions.
176 * @sync_obj_arg: Opaque argument to synchronization object function.
177 * @sync_obj: Pointer to a synchronization object.
178 * @priv_flags: Flags describing buffer object internal state.
179 * @vm_rb: Rb node for the vm rb tree.
180 * @vm_node: Address space manager node.
181 * @offset: The current GPU offset, which can have different meanings
182 * depending on the memory type. For SYSTEM type memory, it should be 0.
183 * @cur_placement: Hint of current placement.
184 *
185 * Base class for TTM buffer object, that deals with data placement and CPU
186 * mappings. GPU mappings are really up to the driver, but for simpler GPUs
187 * the driver can usually use the placement offset @offset directly as the
188 * GPU virtual address. For drivers implementing multiple
189 * GPU memory manager contexts, the driver should manage the address space
190 * in these contexts separately and use these objects to get the correct
191 * placement and caching for these GPU maps. This makes it possible to use
192 * these objects for even quite elaborate memory management schemes.
193 * The destroy member, the API visibility of this object makes it possible
194 * to derive driver specific types.
195 */
196
197struct ttm_buffer_object {
198 /**
199 * Members constant at init.
200 */
201
202 struct ttm_bo_global *glob;
203 struct ttm_bo_device *bdev;
204 unsigned long buffer_start;
205 enum ttm_bo_type type;
206 void (*destroy) (struct ttm_buffer_object *);
207 unsigned long num_pages;
208 uint64_t addr_space_offset;
209 size_t acc_size;
210
211 /**
212 * Members not needing protection.
213 */
214
215 struct kref kref;
216 struct kref list_kref;
217 wait_queue_head_t event_queue;
218
219 /**
220 * Members protected by the bo::reserved lock.
221 */
222
223 struct ttm_mem_reg mem;
224 struct file *persistent_swap_storage;
225 struct ttm_tt *ttm;
226 bool evicted;
227
228 /**
229 * Members protected by the bo::reserved lock only when written to.
230 */
231
232 atomic_t cpu_writers;
233
234 /**
235 * Members protected by the bdev::lru_lock.
236 */
237
238 struct list_head lru;
239 struct list_head ddestroy;
240 struct list_head swap;
241 struct list_head io_reserve_lru;
242 uint32_t val_seq;
243 bool seq_valid;
244
245 /**
246 * Members protected by the bdev::lru_lock
247 * only when written to.
248 */
249
250 atomic_t reserved;
251
252 /**
253 * Members protected by struct buffer_object_device::fence_lock
254 * In addition, setting sync_obj to anything else
255 * than NULL requires bo::reserved to be held. This allows for
256 * checking NULL while reserved but not holding the mentioned lock.
257 */
258
259 void *sync_obj_arg;
260 void *sync_obj;
261 unsigned long priv_flags;
262
263 /**
264 * Members protected by the bdev::vm_lock
265 */
266
267 struct rb_node vm_rb;
268 struct drm_mm_node *vm_node;
269
270
271 /**
272 * Special members that are protected by the reserve lock
273 * and the bo::lock when written to. Can be read with
274 * either of these locks held.
275 */
276
277 unsigned long offset;
278 uint32_t cur_placement;
279};
280
281/**
282 * struct ttm_bo_kmap_obj
283 *
284 * @virtual: The current kernel virtual address.
285 * @page: The page when kmap'ing a single page.
286 * @bo_kmap_type: Type of bo_kmap.
287 *
288 * Object describing a kernel mapping. Since a TTM bo may be located
289 * in various memory types with various caching policies, the
290 * mapping can either be an ioremap, a vmap, a kmap or part of a
291 * premapped region.
292 */
293
294#define TTM_BO_MAP_IOMEM_MASK 0x80
295struct ttm_bo_kmap_obj {
296 void *virtual;
297 struct page *page;
298 enum {
299 ttm_bo_map_iomap = 1 | TTM_BO_MAP_IOMEM_MASK,
300 ttm_bo_map_vmap = 2,
301 ttm_bo_map_kmap = 3,
302 ttm_bo_map_premapped = 4 | TTM_BO_MAP_IOMEM_MASK,
303 } bo_kmap_type;
304 struct ttm_buffer_object *bo;
305};
306
307/**
308 * ttm_bo_reference - reference a struct ttm_buffer_object
309 *
310 * @bo: The buffer object.
311 *
312 * Returns a refcounted pointer to a buffer object.
313 */
314
315static inline struct ttm_buffer_object *
316ttm_bo_reference(struct ttm_buffer_object *bo)
317{
318 kref_get(&bo->kref);
319 return bo;
320}
321
322/**
323 * ttm_bo_wait - wait for buffer idle.
324 *
325 * @bo: The buffer object.
326 * @interruptible: Use interruptible wait.
327 * @no_wait: Return immediately if buffer is busy.
328 *
329 * This function must be called with the bo::mutex held, and makes
330 * sure any previous rendering to the buffer is completed.
331 * Note: It might be necessary to block validations before the
332 * wait by reserving the buffer.
333 * Returns -EBUSY if no_wait is true and the buffer is busy.
334 * Returns -ERESTARTSYS if interrupted by a signal.
335 */
336extern int ttm_bo_wait(struct ttm_buffer_object *bo, bool lazy,
337 bool interruptible, bool no_wait);
338/**
339 * ttm_bo_validate
340 *
341 * @bo: The buffer object.
342 * @placement: Proposed placement for the buffer object.
343 * @interruptible: Sleep interruptible if sleeping.
344 * @no_wait_reserve: Return immediately if other buffers are busy.
345 * @no_wait_gpu: Return immediately if the GPU is busy.
346 *
347 * Changes placement and caching policy of the buffer object
348 * according proposed placement.
349 * Returns
350 * -EINVAL on invalid proposed placement.
351 * -ENOMEM on out-of-memory condition.
352 * -EBUSY if no_wait is true and buffer busy.
353 * -ERESTARTSYS if interrupted by a signal.
354 */
355extern int ttm_bo_validate(struct ttm_buffer_object *bo,
356 struct ttm_placement *placement,
357 bool interruptible, bool no_wait_reserve,
358 bool no_wait_gpu);
359
360/**
361 * ttm_bo_unref
362 *
363 * @bo: The buffer object.
364 *
365 * Unreference and clear a pointer to a buffer object.
366 */
367extern void ttm_bo_unref(struct ttm_buffer_object **bo);
368
369
370/**
371 * ttm_bo_list_ref_sub
372 *
373 * @bo: The buffer object.
374 * @count: The number of references with which to decrease @bo::list_kref;
375 * @never_free: The refcount should not reach zero with this operation.
376 *
377 * Release @count lru list references to this buffer object.
378 */
379extern void ttm_bo_list_ref_sub(struct ttm_buffer_object *bo, int count,
380 bool never_free);
381
382/**
383 * ttm_bo_add_to_lru
384 *
385 * @bo: The buffer object.
386 *
387 * Add this bo to the relevant mem type lru and, if it's backed by
388 * system pages (ttms) to the swap list.
389 * This function must be called with struct ttm_bo_global::lru_lock held, and
390 * is typically called immediately prior to unreserving a bo.
391 */
392extern void ttm_bo_add_to_lru(struct ttm_buffer_object *bo);
393
394/**
395 * ttm_bo_del_from_lru
396 *
397 * @bo: The buffer object.
398 *
399 * Remove this bo from all lru lists used to lookup and reserve an object.
400 * This function must be called with struct ttm_bo_global::lru_lock held,
401 * and is usually called just immediately after the bo has been reserved to
402 * avoid recursive reservation from lru lists.
403 */
404extern int ttm_bo_del_from_lru(struct ttm_buffer_object *bo);
405
406
407/**
408 * ttm_bo_lock_delayed_workqueue
409 *
410 * Prevent the delayed workqueue from running.
411 * Returns
412 * True if the workqueue was queued at the time
413 */
414extern int ttm_bo_lock_delayed_workqueue(struct ttm_bo_device *bdev);
415
416/**
417 * ttm_bo_unlock_delayed_workqueue
418 *
419 * Allows the delayed workqueue to run.
420 */
421extern void ttm_bo_unlock_delayed_workqueue(struct ttm_bo_device *bdev,
422 int resched);
423
424/**
425 * ttm_bo_synccpu_write_grab
426 *
427 * @bo: The buffer object:
428 * @no_wait: Return immediately if buffer is busy.
429 *
430 * Synchronizes a buffer object for CPU RW access. This means
431 * blocking command submission that affects the buffer and
432 * waiting for buffer idle. This lock is recursive.
433 * Returns
434 * -EBUSY if the buffer is busy and no_wait is true.
435 * -ERESTARTSYS if interrupted by a signal.
436 */
437
438extern int
439ttm_bo_synccpu_write_grab(struct ttm_buffer_object *bo, bool no_wait);
440/**
441 * ttm_bo_synccpu_write_release:
442 *
443 * @bo : The buffer object.
444 *
445 * Releases a synccpu lock.
446 */
447extern void ttm_bo_synccpu_write_release(struct ttm_buffer_object *bo);
448
449/**
450 * ttm_bo_init
451 *
452 * @bdev: Pointer to a ttm_bo_device struct.
453 * @bo: Pointer to a ttm_buffer_object to be initialized.
454 * @size: Requested size of buffer object.
455 * @type: Requested type of buffer object.
456 * @flags: Initial placement flags.
457 * @page_alignment: Data alignment in pages.
458 * @buffer_start: Virtual address of user space data backing a
459 * user buffer object.
460 * @interruptible: If needing to sleep to wait for GPU resources,
461 * sleep interruptible.
462 * @persistent_swap_storage: Usually the swap storage is deleted for buffers
463 * pinned in physical memory. If this behaviour is not desired, this member
464 * holds a pointer to a persistent shmem object. Typically, this would
465 * point to the shmem object backing a GEM object if TTM is used to back a
466 * GEM user interface.
467 * @acc_size: Accounted size for this object.
468 * @destroy: Destroy function. Use NULL for kfree().
469 *
470 * This function initializes a pre-allocated struct ttm_buffer_object.
471 * As this object may be part of a larger structure, this function,
472 * together with the @destroy function,
473 * enables driver-specific objects derived from a ttm_buffer_object.
474 * On successful return, the object kref and list_kref are set to 1.
475 * If a failure occurs, the function will call the @destroy function, or
476 * kfree() if @destroy is NULL. Thus, after a failure, dereferencing @bo is
477 * illegal and will likely cause memory corruption.
478 *
479 * Returns
480 * -ENOMEM: Out of memory.
481 * -EINVAL: Invalid placement flags.
482 * -ERESTARTSYS: Interrupted by signal while sleeping waiting for resources.
483 */
484
485extern int ttm_bo_init(struct ttm_bo_device *bdev,
486 struct ttm_buffer_object *bo,
487 unsigned long size,
488 enum ttm_bo_type type,
489 struct ttm_placement *placement,
490 uint32_t page_alignment,
491 unsigned long buffer_start,
492 bool interrubtible,
493 struct file *persistent_swap_storage,
494 size_t acc_size,
495 void (*destroy) (struct ttm_buffer_object *));
496/**
497 * ttm_bo_synccpu_object_init
498 *
499 * @bdev: Pointer to a ttm_bo_device struct.
500 * @bo: Pointer to a ttm_buffer_object to be initialized.
501 * @size: Requested size of buffer object.
502 * @type: Requested type of buffer object.
503 * @flags: Initial placement flags.
504 * @page_alignment: Data alignment in pages.
505 * @buffer_start: Virtual address of user space data backing a
506 * user buffer object.
507 * @interruptible: If needing to sleep while waiting for GPU resources,
508 * sleep interruptible.
509 * @persistent_swap_storage: Usually the swap storage is deleted for buffers
510 * pinned in physical memory. If this behaviour is not desired, this member
511 * holds a pointer to a persistent shmem object. Typically, this would
512 * point to the shmem object backing a GEM object if TTM is used to back a
513 * GEM user interface.
514 * @p_bo: On successful completion *p_bo points to the created object.
515 *
516 * This function allocates a ttm_buffer_object, and then calls ttm_bo_init
517 * on that object. The destroy function is set to kfree().
518 * Returns
519 * -ENOMEM: Out of memory.
520 * -EINVAL: Invalid placement flags.
521 * -ERESTARTSYS: Interrupted by signal while waiting for resources.
522 */
523
524extern int ttm_bo_create(struct ttm_bo_device *bdev,
525 unsigned long size,
526 enum ttm_bo_type type,
527 struct ttm_placement *placement,
528 uint32_t page_alignment,
529 unsigned long buffer_start,
530 bool interruptible,
531 struct file *persistent_swap_storage,
532 struct ttm_buffer_object **p_bo);
533
534/**
535 * ttm_bo_check_placement
536 *
537 * @bo: the buffer object.
538 * @placement: placements
539 *
540 * Performs minimal validity checking on an intended change of
541 * placement flags.
542 * Returns
543 * -EINVAL: Intended change is invalid or not allowed.
544 */
545extern int ttm_bo_check_placement(struct ttm_buffer_object *bo,
546 struct ttm_placement *placement);
547
548/**
549 * ttm_bo_init_mm
550 *
551 * @bdev: Pointer to a ttm_bo_device struct.
552 * @mem_type: The memory type.
553 * @p_size: size managed area in pages.
554 *
555 * Initialize a manager for a given memory type.
556 * Note: if part of driver firstopen, it must be protected from a
557 * potentially racing lastclose.
558 * Returns:
559 * -EINVAL: invalid size or memory type.
560 * -ENOMEM: Not enough memory.
561 * May also return driver-specified errors.
562 */
563
564extern int ttm_bo_init_mm(struct ttm_bo_device *bdev, unsigned type,
565 unsigned long p_size);
566/**
567 * ttm_bo_clean_mm
568 *
569 * @bdev: Pointer to a ttm_bo_device struct.
570 * @mem_type: The memory type.
571 *
572 * Take down a manager for a given memory type after first walking
573 * the LRU list to evict any buffers left alive.
574 *
575 * Normally, this function is part of lastclose() or unload(), and at that
576 * point there shouldn't be any buffers left created by user-space, since
577 * there should've been removed by the file descriptor release() method.
578 * However, before this function is run, make sure to signal all sync objects,
579 * and verify that the delayed delete queue is empty. The driver must also
580 * make sure that there are no NO_EVICT buffers present in this memory type
581 * when the call is made.
582 *
583 * If this function is part of a VT switch, the caller must make sure that
584 * there are no appications currently validating buffers before this
585 * function is called. The caller can do that by first taking the
586 * struct ttm_bo_device::ttm_lock in write mode.
587 *
588 * Returns:
589 * -EINVAL: invalid or uninitialized memory type.
590 * -EBUSY: There are still buffers left in this memory type.
591 */
592
593extern int ttm_bo_clean_mm(struct ttm_bo_device *bdev, unsigned mem_type);
594
595/**
596 * ttm_bo_evict_mm
597 *
598 * @bdev: Pointer to a ttm_bo_device struct.
599 * @mem_type: The memory type.
600 *
601 * Evicts all buffers on the lru list of the memory type.
602 * This is normally part of a VT switch or an
603 * out-of-memory-space-due-to-fragmentation handler.
604 * The caller must make sure that there are no other processes
605 * currently validating buffers, and can do that by taking the
606 * struct ttm_bo_device::ttm_lock in write mode.
607 *
608 * Returns:
609 * -EINVAL: Invalid or uninitialized memory type.
610 * -ERESTARTSYS: The call was interrupted by a signal while waiting to
611 * evict a buffer.
612 */
613
614extern int ttm_bo_evict_mm(struct ttm_bo_device *bdev, unsigned mem_type);
615
616/**
617 * ttm_kmap_obj_virtual
618 *
619 * @map: A struct ttm_bo_kmap_obj returned from ttm_bo_kmap.
620 * @is_iomem: Pointer to an integer that on return indicates 1 if the
621 * virtual map is io memory, 0 if normal memory.
622 *
623 * Returns the virtual address of a buffer object area mapped by ttm_bo_kmap.
624 * If *is_iomem is 1 on return, the virtual address points to an io memory area,
625 * that should strictly be accessed by the iowriteXX() and similar functions.
626 */
627
628static inline void *ttm_kmap_obj_virtual(struct ttm_bo_kmap_obj *map,
629 bool *is_iomem)
630{
631 *is_iomem = !!(map->bo_kmap_type & TTM_BO_MAP_IOMEM_MASK);
632 return map->virtual;
633}
634
635/**
636 * ttm_bo_kmap
637 *
638 * @bo: The buffer object.
639 * @start_page: The first page to map.
640 * @num_pages: Number of pages to map.
641 * @map: pointer to a struct ttm_bo_kmap_obj representing the map.
642 *
643 * Sets up a kernel virtual mapping, using ioremap, vmap or kmap to the
644 * data in the buffer object. The ttm_kmap_obj_virtual function can then be
645 * used to obtain a virtual address to the data.
646 *
647 * Returns
648 * -ENOMEM: Out of memory.
649 * -EINVAL: Invalid range.
650 */
651
652extern int ttm_bo_kmap(struct ttm_buffer_object *bo, unsigned long start_page,
653 unsigned long num_pages, struct ttm_bo_kmap_obj *map);
654
655/**
656 * ttm_bo_kunmap
657 *
658 * @map: Object describing the map to unmap.
659 *
660 * Unmaps a kernel map set up by ttm_bo_kmap.
661 */
662
663extern void ttm_bo_kunmap(struct ttm_bo_kmap_obj *map);
664
665/**
666 * ttm_fbdev_mmap - mmap fbdev memory backed by a ttm buffer object.
667 *
668 * @vma: vma as input from the fbdev mmap method.
669 * @bo: The bo backing the address space. The address space will
670 * have the same size as the bo, and start at offset 0.
671 *
672 * This function is intended to be called by the fbdev mmap method
673 * if the fbdev address space is to be backed by a bo.
674 */
675
676extern int ttm_fbdev_mmap(struct vm_area_struct *vma,
677 struct ttm_buffer_object *bo);
678
679/**
680 * ttm_bo_mmap - mmap out of the ttm device address space.
681 *
682 * @filp: filp as input from the mmap method.
683 * @vma: vma as input from the mmap method.
684 * @bdev: Pointer to the ttm_bo_device with the address space manager.
685 *
686 * This function is intended to be called by the device mmap method.
687 * if the device address space is to be backed by the bo manager.
688 */
689
690extern int ttm_bo_mmap(struct file *filp, struct vm_area_struct *vma,
691 struct ttm_bo_device *bdev);
692
693/**
694 * ttm_bo_io
695 *
696 * @bdev: Pointer to the struct ttm_bo_device.
697 * @filp: Pointer to the struct file attempting to read / write.
698 * @wbuf: User-space pointer to address of buffer to write. NULL on read.
699 * @rbuf: User-space pointer to address of buffer to read into.
700 * Null on write.
701 * @count: Number of bytes to read / write.
702 * @f_pos: Pointer to current file position.
703 * @write: 1 for read, 0 for write.
704 *
705 * This function implements read / write into ttm buffer objects, and is
706 * intended to
707 * be called from the fops::read and fops::write method.
708 * Returns:
709 * See man (2) write, man(2) read. In particular,
710 * the function may return -ERESTARTSYS if
711 * interrupted by a signal.
712 */
713
714extern ssize_t ttm_bo_io(struct ttm_bo_device *bdev, struct file *filp,
715 const char __user *wbuf, char __user *rbuf,
716 size_t count, loff_t *f_pos, bool write);
717
718extern void ttm_bo_swapout_all(struct ttm_bo_device *bdev);
719
720#endif
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
47struct ttm_global;
48
49struct ttm_device;
50
51struct dma_buf_map;
52
53struct drm_mm_node;
54
55struct ttm_placement;
56
57struct ttm_place;
58
59struct ttm_lru_bulk_move;
60
61/**
62 * enum ttm_bo_type
63 *
64 * @ttm_bo_type_device: These are 'normal' buffers that can
65 * be mmapped by user space. Each of these bos occupy a slot in the
66 * device address space, that can be used for normal vm operations.
67 *
68 * @ttm_bo_type_kernel: These buffers are like ttm_bo_type_device buffers,
69 * but they cannot be accessed from user-space. For kernel-only use.
70 *
71 * @ttm_bo_type_sg: Buffer made from dmabuf sg table shared with another
72 * driver.
73 */
74
75enum ttm_bo_type {
76 ttm_bo_type_device,
77 ttm_bo_type_kernel,
78 ttm_bo_type_sg
79};
80
81struct ttm_tt;
82
83/**
84 * struct ttm_buffer_object
85 *
86 * @base: drm_gem_object superclass data.
87 * @bdev: Pointer to the buffer object device structure.
88 * @type: The bo type.
89 * @page_alignment: Page alignment.
90 * @destroy: Destruction function. If NULL, kfree is used.
91 * @num_pages: Actual number of pages.
92 * @kref: Reference count of this buffer object. When this refcount reaches
93 * zero, the object is destroyed or put on the delayed delete list.
94 * @mem: structure describing current placement.
95 * @ttm: TTM structure holding system pages.
96 * @evicted: Whether the object was evicted without user-space knowing.
97 * @deleted: True if the object is only a zombie and already deleted.
98 * @lru: List head for the lru list.
99 * @ddestroy: List head for the delayed destroy list.
100 * @swap: List head for swap LRU list.
101 * @moving: Fence set when BO is moving
102 * @offset: The current GPU offset, which can have different meanings
103 * depending on the memory type. For SYSTEM type memory, it should be 0.
104 * @cur_placement: Hint of current placement.
105 *
106 * Base class for TTM buffer object, that deals with data placement and CPU
107 * mappings. GPU mappings are really up to the driver, but for simpler GPUs
108 * the driver can usually use the placement offset @offset directly as the
109 * GPU virtual address. For drivers implementing multiple
110 * GPU memory manager contexts, the driver should manage the address space
111 * in these contexts separately and use these objects to get the correct
112 * placement and caching for these GPU maps. This makes it possible to use
113 * these objects for even quite elaborate memory management schemes.
114 * The destroy member, the API visibility of this object makes it possible
115 * to derive driver specific types.
116 */
117
118struct ttm_buffer_object {
119 struct drm_gem_object base;
120
121 /**
122 * Members constant at init.
123 */
124
125 struct ttm_device *bdev;
126 enum ttm_bo_type type;
127 uint32_t page_alignment;
128 void (*destroy) (struct ttm_buffer_object *);
129
130 /**
131 * Members not needing protection.
132 */
133 struct kref kref;
134
135 /**
136 * Members protected by the bo::resv::reserved lock.
137 */
138
139 struct ttm_resource *resource;
140 struct ttm_tt *ttm;
141 bool deleted;
142
143 /**
144 * Members protected by the bdev::lru_lock.
145 */
146
147 struct list_head lru;
148 struct list_head ddestroy;
149
150 /**
151 * Members protected by a bo reservation.
152 */
153
154 struct dma_fence *moving;
155 unsigned priority;
156 unsigned pin_count;
157
158 /**
159 * Special members that are protected by the reserve lock
160 * and the bo::lock when written to. Can be read with
161 * either of these locks held.
162 */
163
164 struct sg_table *sg;
165};
166
167/**
168 * struct ttm_bo_kmap_obj
169 *
170 * @virtual: The current kernel virtual address.
171 * @page: The page when kmap'ing a single page.
172 * @bo_kmap_type: Type of bo_kmap.
173 *
174 * Object describing a kernel mapping. Since a TTM bo may be located
175 * in various memory types with various caching policies, the
176 * mapping can either be an ioremap, a vmap, a kmap or part of a
177 * premapped region.
178 */
179
180#define TTM_BO_MAP_IOMEM_MASK 0x80
181struct ttm_bo_kmap_obj {
182 void *virtual;
183 struct page *page;
184 enum {
185 ttm_bo_map_iomap = 1 | TTM_BO_MAP_IOMEM_MASK,
186 ttm_bo_map_vmap = 2,
187 ttm_bo_map_kmap = 3,
188 ttm_bo_map_premapped = 4 | TTM_BO_MAP_IOMEM_MASK,
189 } bo_kmap_type;
190 struct ttm_buffer_object *bo;
191};
192
193/**
194 * struct ttm_operation_ctx
195 *
196 * @interruptible: Sleep interruptible if sleeping.
197 * @no_wait_gpu: Return immediately if the GPU is busy.
198 * @gfp_retry_mayfail: Set the __GFP_RETRY_MAYFAIL when allocation pages.
199 * @allow_res_evict: Allow eviction of reserved BOs. Can be used when multiple
200 * BOs share the same reservation object.
201 * @force_alloc: Don't check the memory account during suspend or CPU page
202 * faults. Should only be used by TTM internally.
203 * @resv: Reservation object to allow reserved evictions with.
204 *
205 * Context for TTM operations like changing buffer placement or general memory
206 * allocation.
207 */
208struct ttm_operation_ctx {
209 bool interruptible;
210 bool no_wait_gpu;
211 bool gfp_retry_mayfail;
212 bool allow_res_evict;
213 bool force_alloc;
214 struct dma_resv *resv;
215 uint64_t bytes_moved;
216};
217
218/**
219 * ttm_bo_get - reference a struct ttm_buffer_object
220 *
221 * @bo: The buffer object.
222 */
223static inline void ttm_bo_get(struct ttm_buffer_object *bo)
224{
225 kref_get(&bo->kref);
226}
227
228/**
229 * ttm_bo_get_unless_zero - reference a struct ttm_buffer_object unless
230 * its refcount has already reached zero.
231 * @bo: The buffer object.
232 *
233 * Used to reference a TTM buffer object in lookups where the object is removed
234 * from the lookup structure during the destructor and for RCU lookups.
235 *
236 * Returns: @bo if the referencing was successful, NULL otherwise.
237 */
238static inline __must_check struct ttm_buffer_object *
239ttm_bo_get_unless_zero(struct ttm_buffer_object *bo)
240{
241 if (!kref_get_unless_zero(&bo->kref))
242 return NULL;
243 return bo;
244}
245
246/**
247 * ttm_bo_wait - wait for buffer idle.
248 *
249 * @bo: The buffer object.
250 * @interruptible: Use interruptible wait.
251 * @no_wait: Return immediately if buffer is busy.
252 *
253 * This function must be called with the bo::mutex held, and makes
254 * sure any previous rendering to the buffer is completed.
255 * Note: It might be necessary to block validations before the
256 * wait by reserving the buffer.
257 * Returns -EBUSY if no_wait is true and the buffer is busy.
258 * Returns -ERESTARTSYS if interrupted by a signal.
259 */
260int ttm_bo_wait(struct ttm_buffer_object *bo, bool interruptible, bool no_wait);
261
262static inline int ttm_bo_wait_ctx(struct ttm_buffer_object *bo, struct ttm_operation_ctx *ctx)
263{
264 return ttm_bo_wait(bo, ctx->interruptible, ctx->no_wait_gpu);
265}
266
267/**
268 * ttm_bo_mem_compat - Check if proposed placement is compatible with a bo
269 *
270 * @placement: Return immediately if buffer is busy.
271 * @mem: The struct ttm_resource indicating the region where the bo resides
272 * @new_flags: Describes compatible placement found
273 *
274 * Returns true if the placement is compatible
275 */
276bool ttm_bo_mem_compat(struct ttm_placement *placement, struct ttm_resource *mem,
277 uint32_t *new_flags);
278
279/**
280 * ttm_bo_validate
281 *
282 * @bo: The buffer object.
283 * @placement: Proposed placement for the buffer object.
284 * @ctx: validation parameters.
285 *
286 * Changes placement and caching policy of the buffer object
287 * according proposed placement.
288 * Returns
289 * -EINVAL on invalid proposed placement.
290 * -ENOMEM on out-of-memory condition.
291 * -EBUSY if no_wait is true and buffer busy.
292 * -ERESTARTSYS if interrupted by a signal.
293 */
294int ttm_bo_validate(struct ttm_buffer_object *bo,
295 struct ttm_placement *placement,
296 struct ttm_operation_ctx *ctx);
297
298/**
299 * ttm_bo_put
300 *
301 * @bo: The buffer object.
302 *
303 * Unreference a buffer object.
304 */
305void ttm_bo_put(struct ttm_buffer_object *bo);
306
307/**
308 * ttm_bo_move_to_lru_tail
309 *
310 * @bo: The buffer object.
311 * @mem: Resource object.
312 * @bulk: optional bulk move structure to remember BO positions
313 *
314 * Move this BO to the tail of all lru lists used to lookup and reserve an
315 * object. This function must be called with struct ttm_global::lru_lock
316 * held, and is used to make a BO less likely to be considered for eviction.
317 */
318void ttm_bo_move_to_lru_tail(struct ttm_buffer_object *bo,
319 struct ttm_resource *mem,
320 struct ttm_lru_bulk_move *bulk);
321
322/**
323 * ttm_bo_bulk_move_lru_tail
324 *
325 * @bulk: bulk move structure
326 *
327 * Bulk move BOs to the LRU tail, only valid to use when driver makes sure that
328 * BO order never changes. Should be called with ttm_global::lru_lock held.
329 */
330void ttm_bo_bulk_move_lru_tail(struct ttm_lru_bulk_move *bulk);
331
332/**
333 * ttm_bo_lock_delayed_workqueue
334 *
335 * Prevent the delayed workqueue from running.
336 * Returns
337 * True if the workqueue was queued at the time
338 */
339int ttm_bo_lock_delayed_workqueue(struct ttm_device *bdev);
340
341/**
342 * ttm_bo_unlock_delayed_workqueue
343 *
344 * Allows the delayed workqueue to run.
345 */
346void ttm_bo_unlock_delayed_workqueue(struct ttm_device *bdev, int resched);
347
348/**
349 * ttm_bo_eviction_valuable
350 *
351 * @bo: The buffer object to evict
352 * @place: the placement we need to make room for
353 *
354 * Check if it is valuable to evict the BO to make room for the given placement.
355 */
356bool ttm_bo_eviction_valuable(struct ttm_buffer_object *bo,
357 const struct ttm_place *place);
358
359/**
360 * ttm_bo_init_reserved
361 *
362 * @bdev: Pointer to a ttm_device struct.
363 * @bo: Pointer to a ttm_buffer_object to be initialized.
364 * @size: Requested size of buffer object.
365 * @type: Requested type of buffer object.
366 * @flags: Initial placement flags.
367 * @page_alignment: Data alignment in pages.
368 * @ctx: TTM operation context for memory allocation.
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
393int ttm_bo_init_reserved(struct ttm_device *bdev,
394 struct ttm_buffer_object *bo,
395 size_t size, enum ttm_bo_type type,
396 struct ttm_placement *placement,
397 uint32_t page_alignment,
398 struct ttm_operation_ctx *ctx,
399 struct sg_table *sg, struct dma_resv *resv,
400 void (*destroy) (struct ttm_buffer_object *));
401
402/**
403 * ttm_bo_init
404 *
405 * @bdev: Pointer to a ttm_device struct.
406 * @bo: Pointer to a ttm_buffer_object to be initialized.
407 * @size: Requested size of buffer object.
408 * @type: Requested type of buffer object.
409 * @flags: Initial placement flags.
410 * @page_alignment: Data alignment in pages.
411 * @interruptible: If needing to sleep to wait for GPU resources,
412 * sleep interruptible.
413 * pinned in physical memory. If this behaviour is not desired, this member
414 * holds a pointer to a persistent shmem object. Typically, this would
415 * point to the shmem object backing a GEM object if TTM is used to back a
416 * GEM user interface.
417 * @resv: Pointer to a dma_resv, or NULL to let ttm allocate one.
418 * @destroy: Destroy function. Use NULL for kfree().
419 *
420 * This function initializes a pre-allocated struct ttm_buffer_object.
421 * As this object may be part of a larger structure, this function,
422 * together with the @destroy function,
423 * enables driver-specific objects derived from a ttm_buffer_object.
424 *
425 * On successful return, the caller owns an object kref to @bo. The kref and
426 * list_kref are usually set to 1, but note that in some situations, other
427 * tasks may already be holding references to @bo as well.
428 *
429 * If a failure occurs, the function will call the @destroy function, or
430 * kfree() if @destroy is NULL. Thus, after a failure, dereferencing @bo is
431 * illegal and will likely cause memory corruption.
432 *
433 * Returns
434 * -ENOMEM: Out of memory.
435 * -EINVAL: Invalid placement flags.
436 * -ERESTARTSYS: Interrupted by signal while sleeping waiting for resources.
437 */
438int ttm_bo_init(struct ttm_device *bdev, struct ttm_buffer_object *bo,
439 size_t size, enum ttm_bo_type type,
440 struct ttm_placement *placement,
441 uint32_t page_alignment, bool interrubtible,
442 struct sg_table *sg, struct dma_resv *resv,
443 void (*destroy) (struct ttm_buffer_object *));
444
445/**
446 * ttm_kmap_obj_virtual
447 *
448 * @map: A struct ttm_bo_kmap_obj returned from ttm_bo_kmap.
449 * @is_iomem: Pointer to an integer that on return indicates 1 if the
450 * virtual map is io memory, 0 if normal memory.
451 *
452 * Returns the virtual address of a buffer object area mapped by ttm_bo_kmap.
453 * If *is_iomem is 1 on return, the virtual address points to an io memory area,
454 * that should strictly be accessed by the iowriteXX() and similar functions.
455 */
456static inline void *ttm_kmap_obj_virtual(struct ttm_bo_kmap_obj *map,
457 bool *is_iomem)
458{
459 *is_iomem = !!(map->bo_kmap_type & TTM_BO_MAP_IOMEM_MASK);
460 return map->virtual;
461}
462
463/**
464 * ttm_bo_kmap
465 *
466 * @bo: The buffer object.
467 * @start_page: The first page to map.
468 * @num_pages: Number of pages to map.
469 * @map: pointer to a struct ttm_bo_kmap_obj representing the map.
470 *
471 * Sets up a kernel virtual mapping, using ioremap, vmap or kmap to the
472 * data in the buffer object. The ttm_kmap_obj_virtual function can then be
473 * used to obtain a virtual address to the data.
474 *
475 * Returns
476 * -ENOMEM: Out of memory.
477 * -EINVAL: Invalid range.
478 */
479int ttm_bo_kmap(struct ttm_buffer_object *bo, unsigned long start_page,
480 unsigned long num_pages, struct ttm_bo_kmap_obj *map);
481
482/**
483 * ttm_bo_kunmap
484 *
485 * @map: Object describing the map to unmap.
486 *
487 * Unmaps a kernel map set up by ttm_bo_kmap.
488 */
489void ttm_bo_kunmap(struct ttm_bo_kmap_obj *map);
490
491/**
492 * ttm_bo_vmap
493 *
494 * @bo: The buffer object.
495 * @map: pointer to a struct dma_buf_map representing the map.
496 *
497 * Sets up a kernel virtual mapping, using ioremap or vmap to the
498 * data in the buffer object. The parameter @map returns the virtual
499 * address as struct dma_buf_map. Unmap the buffer with ttm_bo_vunmap().
500 *
501 * Returns
502 * -ENOMEM: Out of memory.
503 * -EINVAL: Invalid range.
504 */
505int ttm_bo_vmap(struct ttm_buffer_object *bo, struct dma_buf_map *map);
506
507/**
508 * ttm_bo_vunmap
509 *
510 * @bo: The buffer object.
511 * @map: Object describing the map to unmap.
512 *
513 * Unmaps a kernel map set up by ttm_bo_vmap().
514 */
515void ttm_bo_vunmap(struct ttm_buffer_object *bo, struct dma_buf_map *map);
516
517/**
518 * ttm_bo_mmap_obj - mmap memory backed by a ttm buffer object.
519 *
520 * @vma: vma as input from the fbdev mmap method.
521 * @bo: The bo backing the address space.
522 *
523 * Maps a buffer object.
524 */
525int ttm_bo_mmap_obj(struct vm_area_struct *vma, struct ttm_buffer_object *bo);
526
527/**
528 * ttm_bo_io
529 *
530 * @bdev: Pointer to the struct ttm_device.
531 * @filp: Pointer to the struct file attempting to read / write.
532 * @wbuf: User-space pointer to address of buffer to write. NULL on read.
533 * @rbuf: User-space pointer to address of buffer to read into.
534 * Null on write.
535 * @count: Number of bytes to read / write.
536 * @f_pos: Pointer to current file position.
537 * @write: 1 for read, 0 for write.
538 *
539 * This function implements read / write into ttm buffer objects, and is
540 * intended to
541 * be called from the fops::read and fops::write method.
542 * Returns:
543 * See man (2) write, man(2) read. In particular,
544 * the function may return -ERESTARTSYS if
545 * interrupted by a signal.
546 */
547ssize_t ttm_bo_io(struct ttm_device *bdev, struct file *filp,
548 const char __user *wbuf, char __user *rbuf,
549 size_t count, loff_t *f_pos, bool write);
550
551int ttm_bo_swapout(struct ttm_buffer_object *bo, struct ttm_operation_ctx *ctx,
552 gfp_t gfp_flags);
553
554/**
555 * ttm_bo_pin - Pin the buffer object.
556 * @bo: The buffer object to pin
557 *
558 * Make sure the buffer is not evicted any more during memory pressure.
559 */
560static inline void ttm_bo_pin(struct ttm_buffer_object *bo)
561{
562 dma_resv_assert_held(bo->base.resv);
563 WARN_ON_ONCE(!kref_read(&bo->kref));
564 ++bo->pin_count;
565}
566
567/**
568 * ttm_bo_unpin - Unpin the buffer object.
569 * @bo: The buffer object to unpin
570 *
571 * Allows the buffer object to be evicted again during memory pressure.
572 */
573static inline void ttm_bo_unpin(struct ttm_buffer_object *bo)
574{
575 dma_resv_assert_held(bo->base.resv);
576 WARN_ON_ONCE(!kref_read(&bo->kref));
577 if (bo->pin_count)
578 --bo->pin_count;
579 else
580 WARN_ON_ONCE(true);
581}
582
583int ttm_mem_evict_first(struct ttm_device *bdev,
584 struct ttm_resource_manager *man,
585 const struct ttm_place *place,
586 struct ttm_operation_ctx *ctx,
587 struct ww_acquire_ctx *ticket);
588
589/* Default number of pre-faulted pages in the TTM fault handler */
590#define TTM_BO_VM_NUM_PREFAULT 16
591
592vm_fault_t ttm_bo_vm_reserve(struct ttm_buffer_object *bo,
593 struct vm_fault *vmf);
594
595vm_fault_t ttm_bo_vm_fault_reserved(struct vm_fault *vmf,
596 pgprot_t prot,
597 pgoff_t num_prefault,
598 pgoff_t fault_page_size);
599
600vm_fault_t ttm_bo_vm_fault(struct vm_fault *vmf);
601
602void ttm_bo_vm_open(struct vm_area_struct *vma);
603
604void ttm_bo_vm_close(struct vm_area_struct *vma);
605
606int ttm_bo_vm_access(struct vm_area_struct *vma, unsigned long addr,
607 void *buf, int len, int write);
608bool ttm_bo_delayed_delete(struct ttm_device *bdev, bool remove_all);
609
610vm_fault_t ttm_bo_vm_dummy_page(struct vm_fault *vmf, pgprot_t prot);
611
612#endif