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