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
36 #include <linux/kref.h>
37 #include <linux/list.h>
38
39 #include "ttm_device.h"
40
41 #include <uvm/uvm_extern.h>
42
43 /* Default number of pre-faulted pages in the TTM fault handler */
44 #define TTM_BO_VM_NUM_PREFAULT 16
45
46 struct iosys_map;
47
48 struct ttm_global;
49 struct ttm_device;
50 struct ttm_placement;
51 struct ttm_place;
52 struct ttm_resource;
53 struct ttm_resource_manager;
54 struct ttm_tt;
55
56 /**
57 * enum ttm_bo_type
58 *
59 * @ttm_bo_type_device: These are 'normal' buffers that can
60 * be mmapped by user space. Each of these bos occupy a slot in the
61 * device address space, that can be used for normal vm operations.
62 *
63 * @ttm_bo_type_kernel: These buffers are like ttm_bo_type_device buffers,
64 * but they cannot be accessed from user-space. For kernel-only use.
65 *
66 * @ttm_bo_type_sg: Buffer made from dmabuf sg table shared with another
67 * driver.
68 */
69 enum ttm_bo_type {
70 ttm_bo_type_device,
71 ttm_bo_type_kernel,
72 ttm_bo_type_sg
73 };
74
75 /**
76 * struct ttm_buffer_object
77 *
78 * @base: drm_gem_object superclass data.
79 * @bdev: Pointer to the buffer object device structure.
80 * @type: The bo type.
81 * @page_alignment: Page alignment.
82 * @destroy: Destruction function. If NULL, kfree is used.
83 * @kref: Reference count of this buffer object. When this refcount reaches
84 * zero, the object is destroyed or put on the delayed delete list.
85 * @resource: structure describing current placement.
86 * @ttm: TTM structure holding system pages.
87 * @deleted: True if the object is only a zombie and already deleted.
88 * @bulk_move: The bulk move object.
89 * @priority: Priority for LRU, BOs with lower priority are evicted first.
90 * @pin_count: Pin count.
91 *
92 * Base class for TTM buffer object, that deals with data placement and CPU
93 * mappings. GPU mappings are really up to the driver, but for simpler GPUs
94 * the driver can usually use the placement offset @offset directly as the
95 * GPU virtual address. For drivers implementing multiple
96 * GPU memory manager contexts, the driver should manage the address space
97 * in these contexts separately and use these objects to get the correct
98 * placement and caching for these GPU maps. This makes it possible to use
99 * these objects for even quite elaborate memory management schemes.
100 * The destroy member, the API visibility of this object makes it possible
101 * to derive driver specific types.
102 */
103 struct ttm_buffer_object {
104 struct drm_gem_object base;
105
106 /*
107 * Members constant at init.
108 */
109 struct ttm_device *bdev;
110 enum ttm_bo_type type;
111 uint32_t page_alignment;
112 void (*destroy) (struct ttm_buffer_object *);
113
114 /*
115 * Members not needing protection.
116 */
117 struct kref kref;
118
119 /*
120 * Members protected by the bo::resv::reserved lock.
121 */
122 struct ttm_resource *resource;
123 struct ttm_tt *ttm;
124 bool deleted;
125 struct ttm_lru_bulk_move *bulk_move;
126 unsigned priority;
127 unsigned pin_count;
128
129 /**
130 * @delayed_delete: Work item used when we can't delete the BO
131 * immediately
132 */
133 struct work_struct delayed_delete;
134
135 /**
136 * @sg: external source of pages and DMA addresses, protected by the
137 * reservation lock.
138 */
139 struct sg_table *sg;
140 };
141
142 #define TTM_BO_MAP_IOMEM_MASK 0x80
143
144 /**
145 * struct ttm_bo_kmap_obj
146 *
147 * @virtual: The current kernel virtual address.
148 * @page: The page when kmap'ing a single page.
149 * @bo_kmap_type: Type of bo_kmap.
150 * @bo: The TTM BO.
151 *
152 * Object describing a kernel mapping. Since a TTM bo may be located
153 * in various memory types with various caching policies, the
154 * mapping can either be an ioremap, a vmap, a kmap or part of a
155 * premapped region.
156 */
157 struct ttm_bo_kmap_obj {
158 void *virtual;
159 struct vm_page *page;
160 enum {
161 ttm_bo_map_iomap = 1 | TTM_BO_MAP_IOMEM_MASK,
162 ttm_bo_map_vmap = 2,
163 ttm_bo_map_kmap = 3,
164 ttm_bo_map_premapped = 4 | TTM_BO_MAP_IOMEM_MASK,
165 } bo_kmap_type;
166 struct ttm_buffer_object *bo;
167 };
168
169 /**
170 * struct ttm_operation_ctx
171 *
172 * @interruptible: Sleep interruptible if sleeping.
173 * @no_wait_gpu: Return immediately if the GPU is busy.
174 * @gfp_retry_mayfail: Set the __GFP_RETRY_MAYFAIL when allocation pages.
175 * @allow_res_evict: Allow eviction of reserved BOs. Can be used when multiple
176 * BOs share the same reservation object.
177 * @force_alloc: Don't check the memory account during suspend or CPU page
178 * faults. Should only be used by TTM internally.
179 * @resv: Reservation object to allow reserved evictions with.
180 * @bytes_moved: Statistics on how many bytes have been moved.
181 *
182 * Context for TTM operations like changing buffer placement or general memory
183 * allocation.
184 */
185 struct ttm_operation_ctx {
186 bool interruptible;
187 bool no_wait_gpu;
188 bool gfp_retry_mayfail;
189 bool allow_res_evict;
190 bool force_alloc;
191 struct dma_resv *resv;
192 uint64_t bytes_moved;
193 };
194
195 struct ttm_lru_walk;
196
197 /** struct ttm_lru_walk_ops - Operations for a LRU walk. */
198 struct ttm_lru_walk_ops {
199 /**
200 * process_bo - Process this bo.
201 * @walk: struct ttm_lru_walk describing the walk.
202 * @bo: A locked and referenced buffer object.
203 *
204 * Return: Negative error code on error, User-defined positive value
205 * (typically, but not always, size of the processed bo) on success.
206 * On success, the returned values are summed by the walk and the
207 * walk exits when its target is met.
208 * 0 also indicates success, -EBUSY means this bo was skipped.
209 */
210 s64 (*process_bo)(struct ttm_lru_walk *walk, struct ttm_buffer_object *bo);
211 };
212
213 /**
214 * struct ttm_lru_walk - Structure describing a LRU walk.
215 */
216 struct ttm_lru_walk {
217 /** @ops: Pointer to the ops structure. */
218 const struct ttm_lru_walk_ops *ops;
219 /** @ctx: Pointer to the struct ttm_operation_ctx. */
220 struct ttm_operation_ctx *ctx;
221 /** @ticket: The struct ww_acquire_ctx if any. */
222 struct ww_acquire_ctx *ticket;
223 /** @trylock_only: Only use trylock for locking. */
224 bool trylock_only;
225 };
226
227 s64 ttm_lru_walk_for_evict(struct ttm_lru_walk *walk, struct ttm_device *bdev,
228 struct ttm_resource_manager *man, s64 target);
229
230 /**
231 * ttm_bo_get - reference a struct ttm_buffer_object
232 *
233 * @bo: The buffer object.
234 */
ttm_bo_get(struct ttm_buffer_object * bo)235 static inline void ttm_bo_get(struct ttm_buffer_object *bo)
236 {
237 kref_get(&bo->kref);
238 }
239
240 /**
241 * ttm_bo_get_unless_zero - reference a struct ttm_buffer_object unless
242 * its refcount has already reached zero.
243 * @bo: The buffer object.
244 *
245 * Used to reference a TTM buffer object in lookups where the object is removed
246 * from the lookup structure during the destructor and for RCU lookups.
247 *
248 * Returns: @bo if the referencing was successful, NULL otherwise.
249 */
250 static inline __must_check struct ttm_buffer_object *
ttm_bo_get_unless_zero(struct ttm_buffer_object * bo)251 ttm_bo_get_unless_zero(struct ttm_buffer_object *bo)
252 {
253 if (!kref_get_unless_zero(&bo->kref))
254 return NULL;
255 return bo;
256 }
257
258 /**
259 * ttm_bo_reserve:
260 *
261 * @bo: A pointer to a struct ttm_buffer_object.
262 * @interruptible: Sleep interruptible if waiting.
263 * @no_wait: Don't sleep while trying to reserve, rather return -EBUSY.
264 * @ticket: ticket used to acquire the ww_mutex.
265 *
266 * Locks a buffer object for validation. (Or prevents other processes from
267 * locking it for validation), while taking a number of measures to prevent
268 * deadlocks.
269 *
270 * Returns:
271 * -EDEADLK: The reservation may cause a deadlock.
272 * Release all buffer reservations, wait for @bo to become unreserved and
273 * try again.
274 * -ERESTARTSYS: A wait for the buffer to become unreserved was interrupted by
275 * a signal. Release all buffer reservations and return to user-space.
276 * -EBUSY: The function needed to sleep, but @no_wait was true
277 * -EALREADY: Bo already reserved using @ticket. This error code will only
278 * be returned if @use_ticket is set to true.
279 */
ttm_bo_reserve(struct ttm_buffer_object * bo,bool interruptible,bool no_wait,struct ww_acquire_ctx * ticket)280 static inline int ttm_bo_reserve(struct ttm_buffer_object *bo,
281 bool interruptible, bool no_wait,
282 struct ww_acquire_ctx *ticket)
283 {
284 int ret = 0;
285
286 if (no_wait) {
287 bool success;
288
289 if (WARN_ON(ticket))
290 return -EBUSY;
291
292 success = dma_resv_trylock(bo->base.resv);
293 return success ? 0 : -EBUSY;
294 }
295
296 if (interruptible)
297 ret = dma_resv_lock_interruptible(bo->base.resv, ticket);
298 else
299 ret = dma_resv_lock(bo->base.resv, ticket);
300 if (ret == -EINTR)
301 return -ERESTARTSYS;
302 return ret;
303 }
304
305 /**
306 * ttm_bo_reserve_slowpath:
307 * @bo: A pointer to a struct ttm_buffer_object.
308 * @interruptible: Sleep interruptible if waiting.
309 * @ticket: Ticket used to acquire the ww_mutex.
310 *
311 * This is called after ttm_bo_reserve returns -EAGAIN and we backed off
312 * from all our other reservations. Because there are no other reservations
313 * held by us, this function cannot deadlock any more.
314 */
ttm_bo_reserve_slowpath(struct ttm_buffer_object * bo,bool interruptible,struct ww_acquire_ctx * ticket)315 static inline int ttm_bo_reserve_slowpath(struct ttm_buffer_object *bo,
316 bool interruptible,
317 struct ww_acquire_ctx *ticket)
318 {
319 if (interruptible) {
320 int ret = dma_resv_lock_slow_interruptible(bo->base.resv,
321 ticket);
322 if (ret == -EINTR)
323 ret = -ERESTARTSYS;
324 return ret;
325 }
326 dma_resv_lock_slow(bo->base.resv, ticket);
327 return 0;
328 }
329
330 void ttm_bo_move_to_lru_tail(struct ttm_buffer_object *bo);
331
332 static inline void
ttm_bo_move_to_lru_tail_unlocked(struct ttm_buffer_object * bo)333 ttm_bo_move_to_lru_tail_unlocked(struct ttm_buffer_object *bo)
334 {
335 spin_lock(&bo->bdev->lru_lock);
336 ttm_bo_move_to_lru_tail(bo);
337 spin_unlock(&bo->bdev->lru_lock);
338 }
339
ttm_bo_assign_mem(struct ttm_buffer_object * bo,struct ttm_resource * new_mem)340 static inline void ttm_bo_assign_mem(struct ttm_buffer_object *bo,
341 struct ttm_resource *new_mem)
342 {
343 WARN_ON(bo->resource);
344 bo->resource = new_mem;
345 }
346
347 /**
348 * ttm_bo_move_null - assign memory for a buffer object.
349 * @bo: The bo to assign the memory to
350 * @new_mem: The memory to be assigned.
351 *
352 * Assign the memory from new_mem to the memory of the buffer object bo.
353 */
ttm_bo_move_null(struct ttm_buffer_object * bo,struct ttm_resource * new_mem)354 static inline void ttm_bo_move_null(struct ttm_buffer_object *bo,
355 struct ttm_resource *new_mem)
356 {
357 ttm_resource_free(bo, &bo->resource);
358 ttm_bo_assign_mem(bo, new_mem);
359 }
360
361 /**
362 * ttm_bo_unreserve
363 *
364 * @bo: A pointer to a struct ttm_buffer_object.
365 *
366 * Unreserve a previous reservation of @bo.
367 */
ttm_bo_unreserve(struct ttm_buffer_object * bo)368 static inline void ttm_bo_unreserve(struct ttm_buffer_object *bo)
369 {
370 ttm_bo_move_to_lru_tail_unlocked(bo);
371 dma_resv_unlock(bo->base.resv);
372 }
373
374 /**
375 * ttm_kmap_obj_virtual
376 *
377 * @map: A struct ttm_bo_kmap_obj returned from ttm_bo_kmap.
378 * @is_iomem: Pointer to an integer that on return indicates 1 if the
379 * virtual map is io memory, 0 if normal memory.
380 *
381 * Returns the virtual address of a buffer object area mapped by ttm_bo_kmap.
382 * If *is_iomem is 1 on return, the virtual address points to an io memory area,
383 * that should strictly be accessed by the iowriteXX() and similar functions.
384 */
ttm_kmap_obj_virtual(struct ttm_bo_kmap_obj * map,bool * is_iomem)385 static inline void *ttm_kmap_obj_virtual(struct ttm_bo_kmap_obj *map,
386 bool *is_iomem)
387 {
388 *is_iomem = !!(map->bo_kmap_type & TTM_BO_MAP_IOMEM_MASK);
389 return map->virtual;
390 }
391
392 int ttm_bo_wait_ctx(struct ttm_buffer_object *bo,
393 struct ttm_operation_ctx *ctx);
394 int ttm_bo_validate(struct ttm_buffer_object *bo,
395 struct ttm_placement *placement,
396 struct ttm_operation_ctx *ctx);
397 void ttm_bo_put(struct ttm_buffer_object *bo);
398 void ttm_bo_set_bulk_move(struct ttm_buffer_object *bo,
399 struct ttm_lru_bulk_move *bulk);
400 bool ttm_bo_eviction_valuable(struct ttm_buffer_object *bo,
401 const struct ttm_place *place);
402 int ttm_bo_init_reserved(struct ttm_device *bdev, struct ttm_buffer_object *bo,
403 enum ttm_bo_type type, struct ttm_placement *placement,
404 uint32_t alignment, struct ttm_operation_ctx *ctx,
405 struct sg_table *sg, struct dma_resv *resv,
406 void (*destroy)(struct ttm_buffer_object *));
407 int ttm_bo_init_validate(struct ttm_device *bdev, struct ttm_buffer_object *bo,
408 enum ttm_bo_type type, struct ttm_placement *placement,
409 uint32_t alignment, bool interruptible,
410 struct sg_table *sg, struct dma_resv *resv,
411 void (*destroy)(struct ttm_buffer_object *));
412 int ttm_bo_kmap(struct ttm_buffer_object *bo, unsigned long start_page,
413 unsigned long num_pages, struct ttm_bo_kmap_obj *map);
414 void ttm_bo_kunmap(struct ttm_bo_kmap_obj *map);
415 int ttm_bo_vmap(struct ttm_buffer_object *bo, struct iosys_map *map);
416 void ttm_bo_vunmap(struct ttm_buffer_object *bo, struct iosys_map *map);
417 #ifdef __linux__
418 int ttm_bo_mmap_obj(struct vm_area_struct *vma, struct ttm_buffer_object *bo);
419 #else
420 int ttm_bo_mmap_obj(struct ttm_buffer_object *bo);
421 #endif
422 s64 ttm_bo_swapout(struct ttm_device *bdev, struct ttm_operation_ctx *ctx,
423 struct ttm_resource_manager *man, gfp_t gfp_flags,
424 s64 target);
425 void ttm_bo_pin(struct ttm_buffer_object *bo);
426 void ttm_bo_unpin(struct ttm_buffer_object *bo);
427 int ttm_bo_evict_first(struct ttm_device *bdev,
428 struct ttm_resource_manager *man,
429 struct ttm_operation_ctx *ctx);
430 #ifdef __linux__
431 vm_fault_t ttm_bo_vm_reserve(struct ttm_buffer_object *bo,
432 struct vm_fault *vmf);
433 vm_fault_t ttm_bo_vm_fault_reserved(struct vm_fault *vmf,
434 pgprot_t prot,
435 pgoff_t num_prefault);
436 vm_fault_t ttm_bo_vm_fault(struct vm_fault *vmf);
437 void ttm_bo_vm_open(struct vm_area_struct *vma);
438 void ttm_bo_vm_close(struct vm_area_struct *vma);
439 int ttm_bo_vm_access(struct vm_area_struct *vma, unsigned long addr,
440 void *buf, int len, int write);
441 vm_fault_t ttm_bo_vm_dummy_page(struct vm_fault *vmf, pgprot_t prot);
442 #else
443 vm_fault_t ttm_bo_vm_reserve(struct ttm_buffer_object *bo);
444 vm_fault_t ttm_bo_vm_fault_reserved(struct uvm_faultinfo *ufi,
445 vaddr_t vaddr,
446 pgoff_t num_prefault,
447 pgoff_t fault_page_size);
448 int ttm_bo_vm_fault(struct uvm_faultinfo *, vaddr_t, vm_page_t *,
449 int, int, vm_fault_t, vm_prot_t, int);
450 #endif /* !__linux__ */
451
452 int ttm_bo_mem_space(struct ttm_buffer_object *bo,
453 struct ttm_placement *placement,
454 struct ttm_resource **mem,
455 struct ttm_operation_ctx *ctx);
456
457 void ttm_bo_unmap_virtual(struct ttm_buffer_object *bo);
458 /*
459 * ttm_bo_util.c
460 */
461 int ttm_mem_io_reserve(struct ttm_device *bdev,
462 struct ttm_resource *mem);
463 void ttm_mem_io_free(struct ttm_device *bdev,
464 struct ttm_resource *mem);
465 void ttm_move_memcpy(bool clear, u32 num_pages,
466 struct ttm_kmap_iter *dst_iter,
467 struct ttm_kmap_iter *src_iter,
468 bus_space_tag_t memt);
469 int ttm_bo_move_memcpy(struct ttm_buffer_object *bo,
470 struct ttm_operation_ctx *ctx,
471 struct ttm_resource *new_mem);
472 int ttm_bo_move_accel_cleanup(struct ttm_buffer_object *bo,
473 struct dma_fence *fence, bool evict,
474 bool pipeline,
475 struct ttm_resource *new_mem);
476 void ttm_bo_move_sync_cleanup(struct ttm_buffer_object *bo,
477 struct ttm_resource *new_mem);
478 int ttm_bo_pipeline_gutting(struct ttm_buffer_object *bo);
479 pgprot_t ttm_io_prot(struct ttm_buffer_object *bo, struct ttm_resource *res,
480 pgprot_t tmp);
481 void ttm_bo_tt_destroy(struct ttm_buffer_object *bo);
482
483 #endif
484