1 /**************************************************************************
2 *
3 * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
4 * All Rights Reserved.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the
8 * "Software"), to deal in the Software without restriction, including
9 * without limitation the rights to use, copy, modify, merge, publish,
10 * distribute, sub license, and/or sell copies of the Software, and to
11 * permit persons to whom the Software is furnished to do so, subject to
12 * the following conditions:
13 *
14 * The above copyright notice and this permission notice (including the
15 * next paragraph) shall be included in all copies or substantial portions
16 * of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
21 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
22 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
23 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
24 * USE OR OTHER DEALINGS IN THE SOFTWARE.
25 *
26 **************************************************************************/
27 /*
28 * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
29 */
30
31 #ifndef _TTM_BO_API_H_
32 #define _TTM_BO_API_H_
33
34 #include <drm/drm_gem.h>
35 #include <drm/drm_hashtab.h>
36 #include <drm/drm_vma_manager.h>
37 #include <linux/kref.h>
38 #include <linux/list.h>
39 #include <linux/wait.h>
40 #include <linux/mutex.h>
41 #include <linux/mm.h>
42 #include <linux/bitmap.h>
43 #include <linux/dma-resv.h>
44
45 #include "ttm_resource.h"
46
47 struct ttm_bo_global;
48
49 struct ttm_bo_device;
50
51 struct drm_mm_node;
52
53 struct ttm_placement;
54
55 struct ttm_place;
56
57 struct ttm_lru_bulk_move;
58
59 /**
60 * enum ttm_bo_type
61 *
62 * @ttm_bo_type_device: These are 'normal' buffers that can
63 * be mmapped by user space. Each of these bos occupy a slot in the
64 * device address space, that can be used for normal vm operations.
65 *
66 * @ttm_bo_type_kernel: These buffers are like ttm_bo_type_device buffers,
67 * but they cannot be accessed from user-space. For kernel-only use.
68 *
69 * @ttm_bo_type_sg: Buffer made from dmabuf sg table shared with another
70 * driver.
71 */
72
73 enum ttm_bo_type {
74 ttm_bo_type_device,
75 ttm_bo_type_kernel,
76 ttm_bo_type_sg
77 };
78
79 struct ttm_tt;
80
81 /**
82 * struct ttm_buffer_object
83 *
84 * @base: drm_gem_object superclass data.
85 * @bdev: Pointer to the buffer object device structure.
86 * @type: The bo type.
87 * @destroy: Destruction function. If NULL, kfree is used.
88 * @num_pages: Actual number of pages.
89 * @acc_size: Accounted size for this object.
90 * @kref: Reference count of this buffer object. When this refcount reaches
91 * zero, the object is destroyed or put on the delayed delete list.
92 * @mem: structure describing current placement.
93 * @persistent_swap_storage: Usually the swap storage is deleted for buffers
94 * pinned in physical memory. If this behaviour is not desired, this member
95 * holds a pointer to a persistent shmem object.
96 * @ttm: TTM structure holding system pages.
97 * @evicted: Whether the object was evicted without user-space knowing.
98 * @deleted: True if the object is only a zombie and already deleted.
99 * @lru: List head for the lru list.
100 * @ddestroy: List head for the delayed destroy list.
101 * @swap: List head for swap LRU list.
102 * @moving: Fence set when BO is moving
103 * @offset: The current GPU offset, which can have different meanings
104 * depending on the memory type. For SYSTEM type memory, it should be 0.
105 * @cur_placement: Hint of current placement.
106 *
107 * Base class for TTM buffer object, that deals with data placement and CPU
108 * mappings. GPU mappings are really up to the driver, but for simpler GPUs
109 * the driver can usually use the placement offset @offset directly as the
110 * GPU virtual address. For drivers implementing multiple
111 * GPU memory manager contexts, the driver should manage the address space
112 * in these contexts separately and use these objects to get the correct
113 * placement and caching for these GPU maps. This makes it possible to use
114 * these objects for even quite elaborate memory management schemes.
115 * The destroy member, the API visibility of this object makes it possible
116 * to derive driver specific types.
117 */
118
119 struct ttm_buffer_object {
120 struct drm_gem_object base;
121
122 /**
123 * Members constant at init.
124 */
125
126 struct ttm_bo_device *bdev;
127 enum ttm_bo_type type;
128 void (*destroy) (struct ttm_buffer_object *);
129 unsigned long num_pages;
130 size_t acc_size;
131
132 /**
133 * Members not needing protection.
134 */
135 struct kref kref;
136
137 /**
138 * Members protected by the bo::resv::reserved lock.
139 */
140
141 struct ttm_resource mem;
142 struct file *persistent_swap_storage;
143 struct ttm_tt *ttm;
144 bool deleted;
145
146 /**
147 * Members protected by the bdev::lru_lock.
148 */
149
150 struct list_head lru;
151 struct list_head ddestroy;
152 struct list_head swap;
153
154 /**
155 * Members protected by a bo reservation.
156 */
157
158 struct dma_fence *moving;
159 unsigned priority;
160
161 /**
162 * Special members that are protected by the reserve lock
163 * and the bo::lock when written to. Can be read with
164 * either of these locks held.
165 */
166
167 struct sg_table *sg;
168 };
169
170 /**
171 * struct ttm_bo_kmap_obj
172 *
173 * @virtual: The current kernel virtual address.
174 * @page: The page when kmap'ing a single page.
175 * @bo_kmap_type: Type of bo_kmap.
176 *
177 * Object describing a kernel mapping. Since a TTM bo may be located
178 * in various memory types with various caching policies, the
179 * mapping can either be an ioremap, a vmap, a kmap or part of a
180 * premapped region.
181 */
182
183 #define TTM_BO_MAP_IOMEM_MASK 0x80
184 struct ttm_bo_kmap_obj {
185 void *virtual;
186 struct page *page;
187 enum {
188 ttm_bo_map_iomap = 1 | TTM_BO_MAP_IOMEM_MASK,
189 ttm_bo_map_vmap = 2,
190 ttm_bo_map_kmap = 3,
191 ttm_bo_map_premapped = 4 | TTM_BO_MAP_IOMEM_MASK,
192 } bo_kmap_type;
193 struct ttm_buffer_object *bo;
194 };
195
196 /**
197 * struct ttm_operation_ctx
198 *
199 * @interruptible: Sleep interruptible if sleeping.
200 * @no_wait_gpu: Return immediately if the GPU is busy.
201 * @resv: Reservation object to allow reserved evictions with.
202 * @flags: Including the following flags
203 *
204 * Context for TTM operations like changing buffer placement or general memory
205 * allocation.
206 */
207 struct ttm_operation_ctx {
208 bool interruptible;
209 bool no_wait_gpu;
210 struct dma_resv *resv;
211 uint64_t bytes_moved;
212 uint32_t flags;
213 };
214
215 /* Allow eviction of reserved BOs */
216 #define TTM_OPT_FLAG_ALLOW_RES_EVICT 0x1
217 /* when serving page fault or suspend, allow alloc anyway */
218 #define TTM_OPT_FLAG_FORCE_ALLOC 0x2
219
220 /**
221 * ttm_bo_get - reference a struct ttm_buffer_object
222 *
223 * @bo: The buffer object.
224 */
ttm_bo_get(struct ttm_buffer_object * bo)225 static inline void ttm_bo_get(struct ttm_buffer_object *bo)
226 {
227 kref_get(&bo->kref);
228 }
229
230 /**
231 * ttm_bo_get_unless_zero - reference a struct ttm_buffer_object unless
232 * its refcount has already reached zero.
233 * @bo: The buffer object.
234 *
235 * Used to reference a TTM buffer object in lookups where the object is removed
236 * from the lookup structure during the destructor and for RCU lookups.
237 *
238 * Returns: @bo if the referencing was successful, NULL otherwise.
239 */
240 static inline __must_check struct ttm_buffer_object *
ttm_bo_get_unless_zero(struct ttm_buffer_object * bo)241 ttm_bo_get_unless_zero(struct ttm_buffer_object *bo)
242 {
243 if (!kref_get_unless_zero(&bo->kref))
244 return NULL;
245 return bo;
246 }
247
248 /**
249 * ttm_bo_wait - wait for buffer idle.
250 *
251 * @bo: The buffer object.
252 * @interruptible: Use interruptible wait.
253 * @no_wait: Return immediately if buffer is busy.
254 *
255 * This function must be called with the bo::mutex held, and makes
256 * sure any previous rendering to the buffer is completed.
257 * Note: It might be necessary to block validations before the
258 * wait by reserving the buffer.
259 * Returns -EBUSY if no_wait is true and the buffer is busy.
260 * Returns -ERESTARTSYS if interrupted by a signal.
261 */
262 int ttm_bo_wait(struct ttm_buffer_object *bo, bool interruptible, bool no_wait);
263
264 /**
265 * ttm_bo_mem_compat - Check if proposed placement is compatible with a bo
266 *
267 * @placement: Return immediately if buffer is busy.
268 * @mem: The struct ttm_resource indicating the region where the bo resides
269 * @new_flags: Describes compatible placement found
270 *
271 * Returns true if the placement is compatible
272 */
273 bool ttm_bo_mem_compat(struct ttm_placement *placement, struct ttm_resource *mem,
274 uint32_t *new_flags);
275
276 /**
277 * ttm_bo_validate
278 *
279 * @bo: The buffer object.
280 * @placement: Proposed placement for the buffer object.
281 * @ctx: validation parameters.
282 *
283 * Changes placement and caching policy of the buffer object
284 * according proposed placement.
285 * Returns
286 * -EINVAL on invalid proposed placement.
287 * -ENOMEM on out-of-memory condition.
288 * -EBUSY if no_wait is true and buffer busy.
289 * -ERESTARTSYS if interrupted by a signal.
290 */
291 int ttm_bo_validate(struct ttm_buffer_object *bo,
292 struct ttm_placement *placement,
293 struct ttm_operation_ctx *ctx);
294
295 /**
296 * ttm_bo_put
297 *
298 * @bo: The buffer object.
299 *
300 * Unreference a buffer object.
301 */
302 void ttm_bo_put(struct ttm_buffer_object *bo);
303
304 /**
305 * ttm_bo_move_to_lru_tail
306 *
307 * @bo: The buffer object.
308 * @bulk: optional bulk move structure to remember BO positions
309 *
310 * Move this BO to the tail of all lru lists used to lookup and reserve an
311 * object. This function must be called with struct ttm_bo_global::lru_lock
312 * held, and is used to make a BO less likely to be considered for eviction.
313 */
314 void ttm_bo_move_to_lru_tail(struct ttm_buffer_object *bo,
315 struct ttm_lru_bulk_move *bulk);
316
317 /**
318 * ttm_bo_bulk_move_lru_tail
319 *
320 * @bulk: bulk move structure
321 *
322 * Bulk move BOs to the LRU tail, only valid to use when driver makes sure that
323 * BO order never changes. Should be called with ttm_bo_global::lru_lock held.
324 */
325 void ttm_bo_bulk_move_lru_tail(struct ttm_lru_bulk_move *bulk);
326
327 /**
328 * ttm_bo_lock_delayed_workqueue
329 *
330 * Prevent the delayed workqueue from running.
331 * Returns
332 * True if the workqueue was queued at the time
333 */
334 int ttm_bo_lock_delayed_workqueue(struct ttm_bo_device *bdev);
335
336 /**
337 * ttm_bo_unlock_delayed_workqueue
338 *
339 * Allows the delayed workqueue to run.
340 */
341 void ttm_bo_unlock_delayed_workqueue(struct ttm_bo_device *bdev, int resched);
342
343 /**
344 * ttm_bo_eviction_valuable
345 *
346 * @bo: The buffer object to evict
347 * @place: the placement we need to make room for
348 *
349 * Check if it is valuable to evict the BO to make room for the given placement.
350 */
351 bool ttm_bo_eviction_valuable(struct ttm_buffer_object *bo,
352 const struct ttm_place *place);
353
354 size_t ttm_bo_dma_acc_size(struct ttm_bo_device *bdev,
355 unsigned long bo_size,
356 unsigned struct_size);
357
358 /**
359 * ttm_bo_init_reserved
360 *
361 * @bdev: Pointer to a ttm_bo_device struct.
362 * @bo: Pointer to a ttm_buffer_object to be initialized.
363 * @size: Requested size of buffer object.
364 * @type: Requested type of buffer object.
365 * @flags: Initial placement flags.
366 * @page_alignment: Data alignment in pages.
367 * @ctx: TTM operation context for memory allocation.
368 * @acc_size: Accounted size for this object.
369 * @resv: Pointer to a dma_resv, or NULL to let ttm allocate one.
370 * @destroy: Destroy function. Use NULL for kfree().
371 *
372 * This function initializes a pre-allocated struct ttm_buffer_object.
373 * As this object may be part of a larger structure, this function,
374 * together with the @destroy function,
375 * enables driver-specific objects derived from a ttm_buffer_object.
376 *
377 * On successful return, the caller owns an object kref to @bo. The kref and
378 * list_kref are usually set to 1, but note that in some situations, other
379 * tasks may already be holding references to @bo as well.
380 * Furthermore, if resv == NULL, the buffer's reservation lock will be held,
381 * and it is the caller's responsibility to call ttm_bo_unreserve.
382 *
383 * If a failure occurs, the function will call the @destroy function, or
384 * kfree() if @destroy is NULL. Thus, after a failure, dereferencing @bo is
385 * illegal and will likely cause memory corruption.
386 *
387 * Returns
388 * -ENOMEM: Out of memory.
389 * -EINVAL: Invalid placement flags.
390 * -ERESTARTSYS: Interrupted by signal while sleeping waiting for resources.
391 */
392
393 int ttm_bo_init_reserved(struct ttm_bo_device *bdev,
394 struct ttm_buffer_object *bo,
395 unsigned long size,
396 enum ttm_bo_type type,
397 struct ttm_placement *placement,
398 uint32_t page_alignment,
399 struct ttm_operation_ctx *ctx,
400 size_t acc_size,
401 struct sg_table *sg,
402 struct dma_resv *resv,
403 void (*destroy) (struct ttm_buffer_object *));
404
405 /**
406 * ttm_bo_init
407 *
408 * @bdev: Pointer to a ttm_bo_device struct.
409 * @bo: Pointer to a ttm_buffer_object to be initialized.
410 * @size: Requested size of buffer object.
411 * @type: Requested type of buffer object.
412 * @flags: Initial placement flags.
413 * @page_alignment: Data alignment in pages.
414 * @interruptible: If needing to sleep to wait for GPU resources,
415 * sleep interruptible.
416 * pinned in physical memory. If this behaviour is not desired, this member
417 * holds a pointer to a persistent shmem object. Typically, this would
418 * point to the shmem object backing a GEM object if TTM is used to back a
419 * GEM user interface.
420 * @acc_size: Accounted size for this object.
421 * @resv: Pointer to a dma_resv, or NULL to let ttm allocate one.
422 * @destroy: Destroy function. Use NULL for kfree().
423 *
424 * This function initializes a pre-allocated struct ttm_buffer_object.
425 * As this object may be part of a larger structure, this function,
426 * together with the @destroy function,
427 * enables driver-specific objects derived from a ttm_buffer_object.
428 *
429 * On successful return, the caller owns an object kref to @bo. The kref and
430 * list_kref are usually set to 1, but note that in some situations, other
431 * tasks may already be holding references to @bo as well.
432 *
433 * If a failure occurs, the function will call the @destroy function, or
434 * kfree() if @destroy is NULL. Thus, after a failure, dereferencing @bo is
435 * illegal and will likely cause memory corruption.
436 *
437 * Returns
438 * -ENOMEM: Out of memory.
439 * -EINVAL: Invalid placement flags.
440 * -ERESTARTSYS: Interrupted by signal while sleeping waiting for resources.
441 */
442 int ttm_bo_init(struct ttm_bo_device *bdev, struct ttm_buffer_object *bo,
443 unsigned long size, enum ttm_bo_type type,
444 struct ttm_placement *placement,
445 uint32_t page_alignment, bool interrubtible, size_t acc_size,
446 struct sg_table *sg, struct dma_resv *resv,
447 void (*destroy) (struct ttm_buffer_object *));
448
449 /**
450 * ttm_bo_create
451 *
452 * @bdev: Pointer to a ttm_bo_device struct.
453 * @size: Requested size of buffer object.
454 * @type: Requested type of buffer object.
455 * @placement: Initial placement.
456 * @page_alignment: Data alignment in pages.
457 * @interruptible: If needing to sleep while waiting for GPU resources,
458 * sleep interruptible.
459 * @p_bo: On successful completion *p_bo points to the created object.
460 *
461 * This function allocates a ttm_buffer_object, and then calls ttm_bo_init
462 * on that object. The destroy function is set to kfree().
463 * Returns
464 * -ENOMEM: Out of memory.
465 * -EINVAL: Invalid placement flags.
466 * -ERESTARTSYS: Interrupted by signal while waiting for resources.
467 */
468 int ttm_bo_create(struct ttm_bo_device *bdev, unsigned long size,
469 enum ttm_bo_type type, struct ttm_placement *placement,
470 uint32_t page_alignment, bool interruptible,
471 struct ttm_buffer_object **p_bo);
472
473 /**
474 * ttm_bo_evict_mm
475 *
476 * @bdev: Pointer to a ttm_bo_device struct.
477 * @mem_type: The memory type.
478 *
479 * Evicts all buffers on the lru list of the memory type.
480 * This is normally part of a VT switch or an
481 * out-of-memory-space-due-to-fragmentation handler.
482 * The caller must make sure that there are no other processes
483 * currently validating buffers, and can do that by taking the
484 * struct ttm_bo_device::ttm_lock in write mode.
485 *
486 * Returns:
487 * -EINVAL: Invalid or uninitialized memory type.
488 * -ERESTARTSYS: The call was interrupted by a signal while waiting to
489 * evict a buffer.
490 */
491 int ttm_bo_evict_mm(struct ttm_bo_device *bdev, unsigned mem_type);
492
493 /**
494 * ttm_kmap_obj_virtual
495 *
496 * @map: A struct ttm_bo_kmap_obj returned from ttm_bo_kmap.
497 * @is_iomem: Pointer to an integer that on return indicates 1 if the
498 * virtual map is io memory, 0 if normal memory.
499 *
500 * Returns the virtual address of a buffer object area mapped by ttm_bo_kmap.
501 * If *is_iomem is 1 on return, the virtual address points to an io memory area,
502 * that should strictly be accessed by the iowriteXX() and similar functions.
503 */
ttm_kmap_obj_virtual(struct ttm_bo_kmap_obj * map,bool * is_iomem)504 static inline void *ttm_kmap_obj_virtual(struct ttm_bo_kmap_obj *map,
505 bool *is_iomem)
506 {
507 *is_iomem = !!(map->bo_kmap_type & TTM_BO_MAP_IOMEM_MASK);
508 return map->virtual;
509 }
510
511 /**
512 * ttm_bo_kmap
513 *
514 * @bo: The buffer object.
515 * @start_page: The first page to map.
516 * @num_pages: Number of pages to map.
517 * @map: pointer to a struct ttm_bo_kmap_obj representing the map.
518 *
519 * Sets up a kernel virtual mapping, using ioremap, vmap or kmap to the
520 * data in the buffer object. The ttm_kmap_obj_virtual function can then be
521 * used to obtain a virtual address to the data.
522 *
523 * Returns
524 * -ENOMEM: Out of memory.
525 * -EINVAL: Invalid range.
526 */
527 int ttm_bo_kmap(struct ttm_buffer_object *bo, unsigned long start_page,
528 unsigned long num_pages, struct ttm_bo_kmap_obj *map);
529
530 /**
531 * ttm_bo_kunmap
532 *
533 * @map: Object describing the map to unmap.
534 *
535 * Unmaps a kernel map set up by ttm_bo_kmap.
536 */
537 void ttm_bo_kunmap(struct ttm_bo_kmap_obj *map);
538
539 /**
540 * ttm_bo_mmap_obj - mmap memory backed by a ttm buffer object.
541 *
542 * @vma: vma as input from the fbdev mmap method.
543 * @bo: The bo backing the address space.
544 *
545 * Maps a buffer object.
546 */
547 int ttm_bo_mmap_obj(struct vm_area_struct *vma, struct ttm_buffer_object *bo);
548
549 /**
550 * ttm_bo_mmap - mmap out of the ttm device address space.
551 *
552 * @filp: filp as input from the mmap method.
553 * @vma: vma as input from the mmap method.
554 * @bdev: Pointer to the ttm_bo_device with the address space manager.
555 *
556 * This function is intended to be called by the device mmap method.
557 * if the device address space is to be backed by the bo manager.
558 */
559 int ttm_bo_mmap(struct file *filp, struct vm_area_struct *vma,
560 struct ttm_bo_device *bdev);
561
562 /**
563 * ttm_bo_io
564 *
565 * @bdev: Pointer to the struct ttm_bo_device.
566 * @filp: Pointer to the struct file attempting to read / write.
567 * @wbuf: User-space pointer to address of buffer to write. NULL on read.
568 * @rbuf: User-space pointer to address of buffer to read into.
569 * Null on write.
570 * @count: Number of bytes to read / write.
571 * @f_pos: Pointer to current file position.
572 * @write: 1 for read, 0 for write.
573 *
574 * This function implements read / write into ttm buffer objects, and is
575 * intended to
576 * be called from the fops::read and fops::write method.
577 * Returns:
578 * See man (2) write, man(2) read. In particular,
579 * the function may return -ERESTARTSYS if
580 * interrupted by a signal.
581 */
582 ssize_t ttm_bo_io(struct ttm_bo_device *bdev, struct file *filp,
583 const char __user *wbuf, char __user *rbuf,
584 size_t count, loff_t *f_pos, bool write);
585
586 int ttm_bo_swapout(struct ttm_bo_global *glob,
587 struct ttm_operation_ctx *ctx);
588 void ttm_bo_swapout_all(void);
589
590 /**
591 * ttm_bo_uses_embedded_gem_object - check if the given bo uses the
592 * embedded drm_gem_object.
593 *
594 * Most ttm drivers are using gem too, so the embedded
595 * ttm_buffer_object.base will be initialized by the driver (before
596 * calling ttm_bo_init). It is also possible to use ttm without gem
597 * though (vmwgfx does that).
598 *
599 * This helper will figure whenever a given ttm bo is a gem object too
600 * or not.
601 *
602 * @bo: The bo to check.
603 */
ttm_bo_uses_embedded_gem_object(struct ttm_buffer_object * bo)604 static inline bool ttm_bo_uses_embedded_gem_object(struct ttm_buffer_object *bo)
605 {
606 return bo->base.dev != NULL;
607 }
608
609 int ttm_mem_evict_first(struct ttm_bo_device *bdev,
610 struct ttm_resource_manager *man,
611 const struct ttm_place *place,
612 struct ttm_operation_ctx *ctx,
613 struct ww_acquire_ctx *ticket);
614
615 /* Default number of pre-faulted pages in the TTM fault handler */
616 #define TTM_BO_VM_NUM_PREFAULT 16
617
618 vm_fault_t ttm_bo_vm_reserve(struct ttm_buffer_object *bo,
619 struct vm_fault *vmf);
620
621 vm_fault_t ttm_bo_vm_fault_reserved(struct vm_fault *vmf,
622 pgprot_t prot,
623 pgoff_t num_prefault,
624 pgoff_t fault_page_size);
625
626 vm_fault_t ttm_bo_vm_fault(struct vm_fault *vmf);
627
628 void ttm_bo_vm_open(struct vm_area_struct *vma);
629
630 void ttm_bo_vm_close(struct vm_area_struct *vma);
631
632 int ttm_bo_vm_access(struct vm_area_struct *vma, unsigned long addr,
633 void *buf, int len, int write);
634
635 #endif
636