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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/drm_gem.h>
35#include <drm/drm_vma_manager.h>
36#include <linux/kref.h>
37#include <linux/list.h>
38#include <linux/wait.h>
39#include <linux/mutex.h>
40#include <linux/mm.h>
41#include <linux/bitmap.h>
42#include <linux/dma-resv.h>
43
44#include "ttm_resource.h"
45
46struct ttm_global;
47
48struct ttm_device;
49
50struct iosys_map;
51
52struct drm_mm_node;
53
54struct ttm_placement;
55
56struct ttm_place;
57
58/**
59 * enum ttm_bo_type
60 *
61 * @ttm_bo_type_device: These are 'normal' buffers that can
62 * be mmapped by user space. Each of these bos occupy a slot in the
63 * device address space, that can be used for normal vm operations.
64 *
65 * @ttm_bo_type_kernel: These buffers are like ttm_bo_type_device buffers,
66 * but they cannot be accessed from user-space. For kernel-only use.
67 *
68 * @ttm_bo_type_sg: Buffer made from dmabuf sg table shared with another
69 * driver.
70 */
71
72enum ttm_bo_type {
73 ttm_bo_type_device,
74 ttm_bo_type_kernel,
75 ttm_bo_type_sg
76};
77
78struct ttm_tt;
79
80/**
81 * struct ttm_buffer_object
82 *
83 * @base: drm_gem_object superclass data.
84 * @bdev: Pointer to the buffer object device structure.
85 * @type: The bo type.
86 * @page_alignment: Page alignment.
87 * @destroy: Destruction function. If NULL, kfree is used.
88 * @num_pages: Actual number of pages.
89 * @kref: Reference count of this buffer object. When this refcount reaches
90 * zero, the object is destroyed or put on the delayed delete list.
91 * @mem: structure describing current placement.
92 * @ttm: TTM structure holding system pages.
93 * @evicted: Whether the object was evicted without user-space knowing.
94 * @deleted: True if the object is only a zombie and already deleted.
95 * @ddestroy: List head for the delayed destroy list.
96 * @swap: List head for swap LRU list.
97 * @offset: The current GPU offset, which can have different meanings
98 * depending on the memory type. For SYSTEM type memory, it should be 0.
99 * @cur_placement: Hint of current placement.
100 *
101 * Base class for TTM buffer object, that deals with data placement and CPU
102 * mappings. GPU mappings are really up to the driver, but for simpler GPUs
103 * the driver can usually use the placement offset @offset directly as the
104 * GPU virtual address. For drivers implementing multiple
105 * GPU memory manager contexts, the driver should manage the address space
106 * in these contexts separately and use these objects to get the correct
107 * placement and caching for these GPU maps. This makes it possible to use
108 * these objects for even quite elaborate memory management schemes.
109 * The destroy member, the API visibility of this object makes it possible
110 * to derive driver specific types.
111 */
112
113struct ttm_buffer_object {
114 struct drm_gem_object base;
115
116 /**
117 * Members constant at init.
118 */
119
120 struct ttm_device *bdev;
121 enum ttm_bo_type type;
122 uint32_t page_alignment;
123 void (*destroy) (struct ttm_buffer_object *);
124
125 /**
126 * Members not needing protection.
127 */
128 struct kref kref;
129
130 /**
131 * Members protected by the bo::resv::reserved lock.
132 */
133
134 struct ttm_resource *resource;
135 struct ttm_tt *ttm;
136 bool deleted;
137 struct ttm_lru_bulk_move *bulk_move;
138
139 /**
140 * Members protected by the bdev::lru_lock.
141 */
142
143 struct list_head ddestroy;
144
145 /**
146 * Members protected by a bo reservation.
147 */
148
149 unsigned priority;
150 unsigned pin_count;
151
152 /**
153 * Special members that are protected by the reserve lock
154 * and the bo::lock when written to. Can be read with
155 * either of these locks held.
156 */
157
158 struct sg_table *sg;
159};
160
161/**
162 * struct ttm_bo_kmap_obj
163 *
164 * @virtual: The current kernel virtual address.
165 * @page: The page when kmap'ing a single page.
166 * @bo_kmap_type: Type of bo_kmap.
167 *
168 * Object describing a kernel mapping. Since a TTM bo may be located
169 * in various memory types with various caching policies, the
170 * mapping can either be an ioremap, a vmap, a kmap or part of a
171 * premapped region.
172 */
173
174#define TTM_BO_MAP_IOMEM_MASK 0x80
175struct ttm_bo_kmap_obj {
176 void *virtual;
177 struct page *page;
178 enum {
179 ttm_bo_map_iomap = 1 | TTM_BO_MAP_IOMEM_MASK,
180 ttm_bo_map_vmap = 2,
181 ttm_bo_map_kmap = 3,
182 ttm_bo_map_premapped = 4 | TTM_BO_MAP_IOMEM_MASK,
183 } bo_kmap_type;
184 struct ttm_buffer_object *bo;
185};
186
187/**
188 * struct ttm_operation_ctx
189 *
190 * @interruptible: Sleep interruptible if sleeping.
191 * @no_wait_gpu: Return immediately if the GPU is busy.
192 * @gfp_retry_mayfail: Set the __GFP_RETRY_MAYFAIL when allocation pages.
193 * @allow_res_evict: Allow eviction of reserved BOs. Can be used when multiple
194 * BOs share the same reservation object.
195 * @force_alloc: Don't check the memory account during suspend or CPU page
196 * faults. Should only be used by TTM internally.
197 * @resv: Reservation object to allow reserved evictions with.
198 *
199 * Context for TTM operations like changing buffer placement or general memory
200 * allocation.
201 */
202struct ttm_operation_ctx {
203 bool interruptible;
204 bool no_wait_gpu;
205 bool gfp_retry_mayfail;
206 bool allow_res_evict;
207 bool force_alloc;
208 struct dma_resv *resv;
209 uint64_t bytes_moved;
210};
211
212/**
213 * ttm_bo_get - reference a struct ttm_buffer_object
214 *
215 * @bo: The buffer object.
216 */
217static inline void ttm_bo_get(struct ttm_buffer_object *bo)
218{
219 kref_get(&bo->kref);
220}
221
222/**
223 * ttm_bo_get_unless_zero - reference a struct ttm_buffer_object unless
224 * its refcount has already reached zero.
225 * @bo: The buffer object.
226 *
227 * Used to reference a TTM buffer object in lookups where the object is removed
228 * from the lookup structure during the destructor and for RCU lookups.
229 *
230 * Returns: @bo if the referencing was successful, NULL otherwise.
231 */
232static inline __must_check struct ttm_buffer_object *
233ttm_bo_get_unless_zero(struct ttm_buffer_object *bo)
234{
235 if (!kref_get_unless_zero(&bo->kref))
236 return NULL;
237 return bo;
238}
239
240/**
241 * ttm_bo_wait - wait for buffer idle.
242 *
243 * @bo: The buffer object.
244 * @interruptible: Use interruptible wait.
245 * @no_wait: Return immediately if buffer is busy.
246 *
247 * This function must be called with the bo::mutex held, and makes
248 * sure any previous rendering to the buffer is completed.
249 * Note: It might be necessary to block validations before the
250 * wait by reserving the buffer.
251 * Returns -EBUSY if no_wait is true and the buffer is busy.
252 * Returns -ERESTARTSYS if interrupted by a signal.
253 */
254int ttm_bo_wait(struct ttm_buffer_object *bo, bool interruptible, bool no_wait);
255
256static inline int ttm_bo_wait_ctx(struct ttm_buffer_object *bo, struct ttm_operation_ctx *ctx)
257{
258 return ttm_bo_wait(bo, ctx->interruptible, ctx->no_wait_gpu);
259}
260
261/**
262 * ttm_bo_validate
263 *
264 * @bo: The buffer object.
265 * @placement: Proposed placement for the buffer object.
266 * @ctx: validation parameters.
267 *
268 * Changes placement and caching policy of the buffer object
269 * according proposed placement.
270 * Returns
271 * -EINVAL on invalid proposed placement.
272 * -ENOMEM on out-of-memory condition.
273 * -EBUSY if no_wait is true and buffer busy.
274 * -ERESTARTSYS if interrupted by a signal.
275 */
276int ttm_bo_validate(struct ttm_buffer_object *bo,
277 struct ttm_placement *placement,
278 struct ttm_operation_ctx *ctx);
279
280/**
281 * ttm_bo_put
282 *
283 * @bo: The buffer object.
284 *
285 * Unreference a buffer object.
286 */
287void ttm_bo_put(struct ttm_buffer_object *bo);
288
289void ttm_bo_move_to_lru_tail(struct ttm_buffer_object *bo);
290void ttm_bo_set_bulk_move(struct ttm_buffer_object *bo,
291 struct ttm_lru_bulk_move *bulk);
292
293/**
294 * ttm_bo_lock_delayed_workqueue
295 *
296 * Prevent the delayed workqueue from running.
297 * Returns
298 * True if the workqueue was queued at the time
299 */
300int ttm_bo_lock_delayed_workqueue(struct ttm_device *bdev);
301
302/**
303 * ttm_bo_unlock_delayed_workqueue
304 *
305 * Allows the delayed workqueue to run.
306 */
307void ttm_bo_unlock_delayed_workqueue(struct ttm_device *bdev, int resched);
308
309/**
310 * ttm_bo_eviction_valuable
311 *
312 * @bo: The buffer object to evict
313 * @place: the placement we need to make room for
314 *
315 * Check if it is valuable to evict the BO to make room for the given placement.
316 */
317bool ttm_bo_eviction_valuable(struct ttm_buffer_object *bo,
318 const struct ttm_place *place);
319
320int ttm_bo_init_reserved(struct ttm_device *bdev, struct ttm_buffer_object *bo,
321 enum ttm_bo_type type, struct ttm_placement *placement,
322 uint32_t alignment, struct ttm_operation_ctx *ctx,
323 struct sg_table *sg, struct dma_resv *resv,
324 void (*destroy) (struct ttm_buffer_object *));
325int ttm_bo_init_validate(struct ttm_device *bdev, struct ttm_buffer_object *bo,
326 enum ttm_bo_type type, struct ttm_placement *placement,
327 uint32_t alignment, bool interruptible,
328 struct sg_table *sg, struct dma_resv *resv,
329 void (*destroy) (struct ttm_buffer_object *));
330
331/**
332 * ttm_kmap_obj_virtual
333 *
334 * @map: A struct ttm_bo_kmap_obj returned from ttm_bo_kmap.
335 * @is_iomem: Pointer to an integer that on return indicates 1 if the
336 * virtual map is io memory, 0 if normal memory.
337 *
338 * Returns the virtual address of a buffer object area mapped by ttm_bo_kmap.
339 * If *is_iomem is 1 on return, the virtual address points to an io memory area,
340 * that should strictly be accessed by the iowriteXX() and similar functions.
341 */
342static inline void *ttm_kmap_obj_virtual(struct ttm_bo_kmap_obj *map,
343 bool *is_iomem)
344{
345 *is_iomem = !!(map->bo_kmap_type & TTM_BO_MAP_IOMEM_MASK);
346 return map->virtual;
347}
348
349/**
350 * ttm_bo_kmap
351 *
352 * @bo: The buffer object.
353 * @start_page: The first page to map.
354 * @num_pages: Number of pages to map.
355 * @map: pointer to a struct ttm_bo_kmap_obj representing the map.
356 *
357 * Sets up a kernel virtual mapping, using ioremap, vmap or kmap to the
358 * data in the buffer object. The ttm_kmap_obj_virtual function can then be
359 * used to obtain a virtual address to the data.
360 *
361 * Returns
362 * -ENOMEM: Out of memory.
363 * -EINVAL: Invalid range.
364 */
365int ttm_bo_kmap(struct ttm_buffer_object *bo, unsigned long start_page,
366 unsigned long num_pages, struct ttm_bo_kmap_obj *map);
367
368/**
369 * ttm_bo_kunmap
370 *
371 * @map: Object describing the map to unmap.
372 *
373 * Unmaps a kernel map set up by ttm_bo_kmap.
374 */
375void ttm_bo_kunmap(struct ttm_bo_kmap_obj *map);
376
377/**
378 * ttm_bo_vmap
379 *
380 * @bo: The buffer object.
381 * @map: pointer to a struct iosys_map representing the map.
382 *
383 * Sets up a kernel virtual mapping, using ioremap or vmap to the
384 * data in the buffer object. The parameter @map returns the virtual
385 * address as struct iosys_map. Unmap the buffer with ttm_bo_vunmap().
386 *
387 * Returns
388 * -ENOMEM: Out of memory.
389 * -EINVAL: Invalid range.
390 */
391int ttm_bo_vmap(struct ttm_buffer_object *bo, struct iosys_map *map);
392
393/**
394 * ttm_bo_vunmap
395 *
396 * @bo: The buffer object.
397 * @map: Object describing the map to unmap.
398 *
399 * Unmaps a kernel map set up by ttm_bo_vmap().
400 */
401void ttm_bo_vunmap(struct ttm_buffer_object *bo, struct iosys_map *map);
402
403/**
404 * ttm_bo_mmap_obj - mmap memory backed by a ttm buffer object.
405 *
406 * @vma: vma as input from the fbdev mmap method.
407 * @bo: The bo backing the address space.
408 *
409 * Maps a buffer object.
410 */
411int ttm_bo_mmap_obj(struct vm_area_struct *vma, struct ttm_buffer_object *bo);
412
413/**
414 * ttm_bo_io
415 *
416 * @bdev: Pointer to the struct ttm_device.
417 * @filp: Pointer to the struct file attempting to read / write.
418 * @wbuf: User-space pointer to address of buffer to write. NULL on read.
419 * @rbuf: User-space pointer to address of buffer to read into.
420 * Null on write.
421 * @count: Number of bytes to read / write.
422 * @f_pos: Pointer to current file position.
423 * @write: 1 for read, 0 for write.
424 *
425 * This function implements read / write into ttm buffer objects, and is
426 * intended to
427 * be called from the fops::read and fops::write method.
428 * Returns:
429 * See man (2) write, man(2) read. In particular,
430 * the function may return -ERESTARTSYS if
431 * interrupted by a signal.
432 */
433ssize_t ttm_bo_io(struct ttm_device *bdev, struct file *filp,
434 const char __user *wbuf, char __user *rbuf,
435 size_t count, loff_t *f_pos, bool write);
436
437int ttm_bo_swapout(struct ttm_buffer_object *bo, struct ttm_operation_ctx *ctx,
438 gfp_t gfp_flags);
439
440void ttm_bo_pin(struct ttm_buffer_object *bo);
441void ttm_bo_unpin(struct ttm_buffer_object *bo);
442
443int ttm_mem_evict_first(struct ttm_device *bdev,
444 struct ttm_resource_manager *man,
445 const struct ttm_place *place,
446 struct ttm_operation_ctx *ctx,
447 struct ww_acquire_ctx *ticket);
448
449/* Default number of pre-faulted pages in the TTM fault handler */
450#define TTM_BO_VM_NUM_PREFAULT 16
451
452vm_fault_t ttm_bo_vm_reserve(struct ttm_buffer_object *bo,
453 struct vm_fault *vmf);
454
455vm_fault_t ttm_bo_vm_fault_reserved(struct vm_fault *vmf,
456 pgprot_t prot,
457 pgoff_t num_prefault);
458
459vm_fault_t ttm_bo_vm_fault(struct vm_fault *vmf);
460
461void ttm_bo_vm_open(struct vm_area_struct *vma);
462
463void ttm_bo_vm_close(struct vm_area_struct *vma);
464
465int ttm_bo_vm_access(struct vm_area_struct *vma, unsigned long addr,
466 void *buf, int len, int write);
467bool ttm_bo_delayed_delete(struct ttm_device *bdev, bool remove_all);
468
469vm_fault_t ttm_bo_vm_dummy_page(struct vm_fault *vmf, pgprot_t prot);
470
471#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_hashtab.h>
35#include <drm/drm_vma_manager.h>
36#include <linux/kref.h>
37#include <linux/list.h>
38#include <linux/wait.h>
39#include <linux/mutex.h>
40#include <linux/mm.h>
41#include <linux/bitmap.h>
42#include <linux/reservation.h>
43
44struct ttm_bo_device;
45
46struct drm_mm_node;
47
48/**
49 * struct ttm_place
50 *
51 * @fpfn: first valid page frame number to put the object
52 * @lpfn: last valid page frame number to put the object
53 * @flags: memory domain and caching flags for the object
54 *
55 * Structure indicating a possible place to put an object.
56 */
57struct ttm_place {
58 unsigned fpfn;
59 unsigned lpfn;
60 uint32_t flags;
61};
62
63/**
64 * struct ttm_placement
65 *
66 * @num_placement: number of preferred placements
67 * @placement: preferred placements
68 * @num_busy_placement: number of preferred placements when need to evict buffer
69 * @busy_placement: preferred placements when need to evict buffer
70 *
71 * Structure indicating the placement you request for an object.
72 */
73struct ttm_placement {
74 unsigned num_placement;
75 const struct ttm_place *placement;
76 unsigned num_busy_placement;
77 const struct ttm_place *busy_placement;
78};
79
80/**
81 * struct ttm_bus_placement
82 *
83 * @addr: mapped virtual address
84 * @base: bus base address
85 * @is_iomem: is this io memory ?
86 * @size: size in byte
87 * @offset: offset from the base address
88 * @io_reserved_vm: The VM system has a refcount in @io_reserved_count
89 * @io_reserved_count: Refcounting the numbers of callers to ttm_mem_io_reserve
90 *
91 * Structure indicating the bus placement of an object.
92 */
93struct ttm_bus_placement {
94 void *addr;
95 phys_addr_t base;
96 unsigned long size;
97 unsigned long offset;
98 bool is_iomem;
99 bool io_reserved_vm;
100 uint64_t io_reserved_count;
101};
102
103
104/**
105 * struct ttm_mem_reg
106 *
107 * @mm_node: Memory manager node.
108 * @size: Requested size of memory region.
109 * @num_pages: Actual size of memory region in pages.
110 * @page_alignment: Page alignment.
111 * @placement: Placement flags.
112 * @bus: Placement on io bus accessible to the CPU
113 *
114 * Structure indicating the placement and space resources used by a
115 * buffer object.
116 */
117
118struct ttm_mem_reg {
119 void *mm_node;
120 unsigned long start;
121 unsigned long size;
122 unsigned long num_pages;
123 uint32_t page_alignment;
124 uint32_t mem_type;
125 uint32_t placement;
126 struct ttm_bus_placement bus;
127};
128
129/**
130 * enum ttm_bo_type
131 *
132 * @ttm_bo_type_device: These are 'normal' buffers that can
133 * be mmapped by user space. Each of these bos occupy a slot in the
134 * device address space, that can be used for normal vm operations.
135 *
136 * @ttm_bo_type_kernel: These buffers are like ttm_bo_type_device buffers,
137 * but they cannot be accessed from user-space. For kernel-only use.
138 *
139 * @ttm_bo_type_sg: Buffer made from dmabuf sg table shared with another
140 * driver.
141 */
142
143enum ttm_bo_type {
144 ttm_bo_type_device,
145 ttm_bo_type_kernel,
146 ttm_bo_type_sg
147};
148
149struct ttm_tt;
150
151/**
152 * struct ttm_buffer_object
153 *
154 * @bdev: Pointer to the buffer object device structure.
155 * @type: The bo type.
156 * @destroy: Destruction function. If NULL, kfree is used.
157 * @num_pages: Actual number of pages.
158 * @acc_size: Accounted size for this object.
159 * @kref: Reference count of this buffer object. When this refcount reaches
160 * zero, the object is put on the delayed delete list.
161 * @list_kref: List reference count of this buffer object. This member is
162 * used to avoid destruction while the buffer object is still on a list.
163 * Lru lists may keep one refcount, the delayed delete list, and kref != 0
164 * keeps one refcount. When this refcount reaches zero,
165 * the object is destroyed.
166 * @mem: structure describing current placement.
167 * @persistent_swap_storage: Usually the swap storage is deleted for buffers
168 * pinned in physical memory. If this behaviour is not desired, this member
169 * holds a pointer to a persistent shmem object.
170 * @ttm: TTM structure holding system pages.
171 * @evicted: Whether the object was evicted without user-space knowing.
172 * @cpu_writes: For synchronization. Number of cpu writers.
173 * @lru: List head for the lru list.
174 * @ddestroy: List head for the delayed destroy list.
175 * @swap: List head for swap LRU list.
176 * @priv_flags: Flags describing buffer object internal state.
177 * @vma_node: Address space manager node.
178 * @offset: The current GPU offset, which can have different meanings
179 * depending on the memory type. For SYSTEM type memory, it should be 0.
180 * @cur_placement: Hint of current placement.
181 * @wu_mutex: Wait unreserved mutex.
182 *
183 * Base class for TTM buffer object, that deals with data placement and CPU
184 * mappings. GPU mappings are really up to the driver, but for simpler GPUs
185 * the driver can usually use the placement offset @offset directly as the
186 * GPU virtual address. For drivers implementing multiple
187 * GPU memory manager contexts, the driver should manage the address space
188 * in these contexts separately and use these objects to get the correct
189 * placement and caching for these GPU maps. This makes it possible to use
190 * these objects for even quite elaborate memory management schemes.
191 * The destroy member, the API visibility of this object makes it possible
192 * to derive driver specific types.
193 */
194
195struct ttm_buffer_object {
196 /**
197 * Members constant at init.
198 */
199
200 struct ttm_bo_global *glob;
201 struct ttm_bo_device *bdev;
202 enum ttm_bo_type type;
203 void (*destroy) (struct ttm_buffer_object *);
204 unsigned long num_pages;
205 size_t acc_size;
206
207 /**
208 * Members not needing protection.
209 */
210
211 struct kref kref;
212 struct kref list_kref;
213
214 /**
215 * Members protected by the bo::resv::reserved lock.
216 */
217
218 struct ttm_mem_reg mem;
219 struct file *persistent_swap_storage;
220 struct ttm_tt *ttm;
221 bool evicted;
222
223 /**
224 * Members protected by the bo::reserved lock only when written to.
225 */
226
227 atomic_t cpu_writers;
228
229 /**
230 * Members protected by the bdev::lru_lock.
231 */
232
233 struct list_head lru;
234 struct list_head ddestroy;
235 struct list_head swap;
236 struct list_head io_reserve_lru;
237
238 /**
239 * Members protected by a bo reservation.
240 */
241
242 unsigned long priv_flags;
243
244 struct drm_vma_offset_node vma_node;
245
246 /**
247 * Special members that are protected by the reserve lock
248 * and the bo::lock when written to. Can be read with
249 * either of these locks held.
250 */
251
252 uint64_t offset; /* GPU address space is independent of CPU word size */
253 uint32_t cur_placement;
254
255 struct sg_table *sg;
256
257 struct reservation_object *resv;
258 struct reservation_object ttm_resv;
259 struct mutex wu_mutex;
260};
261
262/**
263 * struct ttm_bo_kmap_obj
264 *
265 * @virtual: The current kernel virtual address.
266 * @page: The page when kmap'ing a single page.
267 * @bo_kmap_type: Type of bo_kmap.
268 *
269 * Object describing a kernel mapping. Since a TTM bo may be located
270 * in various memory types with various caching policies, the
271 * mapping can either be an ioremap, a vmap, a kmap or part of a
272 * premapped region.
273 */
274
275#define TTM_BO_MAP_IOMEM_MASK 0x80
276struct ttm_bo_kmap_obj {
277 void *virtual;
278 struct page *page;
279 enum {
280 ttm_bo_map_iomap = 1 | TTM_BO_MAP_IOMEM_MASK,
281 ttm_bo_map_vmap = 2,
282 ttm_bo_map_kmap = 3,
283 ttm_bo_map_premapped = 4 | TTM_BO_MAP_IOMEM_MASK,
284 } bo_kmap_type;
285 struct ttm_buffer_object *bo;
286};
287
288/**
289 * ttm_bo_reference - reference a struct ttm_buffer_object
290 *
291 * @bo: The buffer object.
292 *
293 * Returns a refcounted pointer to a buffer object.
294 */
295
296static inline struct ttm_buffer_object *
297ttm_bo_reference(struct ttm_buffer_object *bo)
298{
299 kref_get(&bo->kref);
300 return bo;
301}
302
303/**
304 * ttm_bo_wait - wait for buffer idle.
305 *
306 * @bo: The buffer object.
307 * @interruptible: Use interruptible wait.
308 * @no_wait: Return immediately if buffer is busy.
309 *
310 * This function must be called with the bo::mutex held, and makes
311 * sure any previous rendering to the buffer is completed.
312 * Note: It might be necessary to block validations before the
313 * wait by reserving the buffer.
314 * Returns -EBUSY if no_wait is true and the buffer is busy.
315 * Returns -ERESTARTSYS if interrupted by a signal.
316 */
317extern int ttm_bo_wait(struct ttm_buffer_object *bo, bool lazy,
318 bool interruptible, bool no_wait);
319/**
320 * ttm_bo_validate
321 *
322 * @bo: The buffer object.
323 * @placement: Proposed placement for the buffer object.
324 * @interruptible: Sleep interruptible if sleeping.
325 * @no_wait_gpu: Return immediately if the GPU is busy.
326 *
327 * Changes placement and caching policy of the buffer object
328 * according proposed placement.
329 * Returns
330 * -EINVAL on invalid proposed placement.
331 * -ENOMEM on out-of-memory condition.
332 * -EBUSY if no_wait is true and buffer busy.
333 * -ERESTARTSYS if interrupted by a signal.
334 */
335extern int ttm_bo_validate(struct ttm_buffer_object *bo,
336 struct ttm_placement *placement,
337 bool interruptible,
338 bool no_wait_gpu);
339
340/**
341 * ttm_bo_unref
342 *
343 * @bo: The buffer object.
344 *
345 * Unreference and clear a pointer to a buffer object.
346 */
347extern void ttm_bo_unref(struct ttm_buffer_object **bo);
348
349
350/**
351 * ttm_bo_list_ref_sub
352 *
353 * @bo: The buffer object.
354 * @count: The number of references with which to decrease @bo::list_kref;
355 * @never_free: The refcount should not reach zero with this operation.
356 *
357 * Release @count lru list references to this buffer object.
358 */
359extern void ttm_bo_list_ref_sub(struct ttm_buffer_object *bo, int count,
360 bool never_free);
361
362/**
363 * ttm_bo_add_to_lru
364 *
365 * @bo: The buffer object.
366 *
367 * Add this bo to the relevant mem type lru and, if it's backed by
368 * system pages (ttms) to the swap list.
369 * This function must be called with struct ttm_bo_global::lru_lock held, and
370 * is typically called immediately prior to unreserving a bo.
371 */
372extern void ttm_bo_add_to_lru(struct ttm_buffer_object *bo);
373
374/**
375 * ttm_bo_del_from_lru
376 *
377 * @bo: The buffer object.
378 *
379 * Remove this bo from all lru lists used to lookup and reserve an object.
380 * This function must be called with struct ttm_bo_global::lru_lock held,
381 * and is usually called just immediately after the bo has been reserved to
382 * avoid recursive reservation from lru lists.
383 */
384extern int ttm_bo_del_from_lru(struct ttm_buffer_object *bo);
385
386/**
387 * ttm_bo_move_to_lru_tail
388 *
389 * @bo: The buffer object.
390 *
391 * Move this BO to the tail of all lru lists used to lookup and reserve an
392 * object. This function must be called with struct ttm_bo_global::lru_lock
393 * held, and is used to make a BO less likely to be considered for eviction.
394 */
395extern void ttm_bo_move_to_lru_tail(struct ttm_buffer_object *bo);
396
397/**
398 * ttm_bo_lock_delayed_workqueue
399 *
400 * Prevent the delayed workqueue from running.
401 * Returns
402 * True if the workqueue was queued at the time
403 */
404extern int ttm_bo_lock_delayed_workqueue(struct ttm_bo_device *bdev);
405
406/**
407 * ttm_bo_unlock_delayed_workqueue
408 *
409 * Allows the delayed workqueue to run.
410 */
411extern void ttm_bo_unlock_delayed_workqueue(struct ttm_bo_device *bdev,
412 int resched);
413
414/**
415 * ttm_bo_synccpu_write_grab
416 *
417 * @bo: The buffer object:
418 * @no_wait: Return immediately if buffer is busy.
419 *
420 * Synchronizes a buffer object for CPU RW access. This means
421 * command submission that affects the buffer will return -EBUSY
422 * until ttm_bo_synccpu_write_release is called.
423 *
424 * Returns
425 * -EBUSY if the buffer is busy and no_wait is true.
426 * -ERESTARTSYS if interrupted by a signal.
427 */
428extern int
429ttm_bo_synccpu_write_grab(struct ttm_buffer_object *bo, bool no_wait);
430
431/**
432 * ttm_bo_synccpu_write_release:
433 *
434 * @bo : The buffer object.
435 *
436 * Releases a synccpu lock.
437 */
438extern void ttm_bo_synccpu_write_release(struct ttm_buffer_object *bo);
439
440/**
441 * ttm_bo_acc_size
442 *
443 * @bdev: Pointer to a ttm_bo_device struct.
444 * @bo_size: size of the buffer object in byte.
445 * @struct_size: size of the structure holding buffer object datas
446 *
447 * Returns size to account for a buffer object
448 */
449size_t ttm_bo_acc_size(struct ttm_bo_device *bdev,
450 unsigned long bo_size,
451 unsigned struct_size);
452size_t ttm_bo_dma_acc_size(struct ttm_bo_device *bdev,
453 unsigned long bo_size,
454 unsigned struct_size);
455
456/**
457 * ttm_bo_init
458 *
459 * @bdev: Pointer to a ttm_bo_device struct.
460 * @bo: Pointer to a ttm_buffer_object to be initialized.
461 * @size: Requested size of buffer object.
462 * @type: Requested type of buffer object.
463 * @flags: Initial placement flags.
464 * @page_alignment: Data alignment in pages.
465 * @interruptible: If needing to sleep to wait for GPU resources,
466 * sleep interruptible.
467 * @persistent_swap_storage: Usually the swap storage is deleted for buffers
468 * pinned in physical memory. If this behaviour is not desired, this member
469 * holds a pointer to a persistent shmem object. Typically, this would
470 * point to the shmem object backing a GEM object if TTM is used to back a
471 * GEM user interface.
472 * @acc_size: Accounted size for this object.
473 * @resv: Pointer to a reservation_object, or NULL to let ttm allocate one.
474 * @destroy: Destroy function. Use NULL for kfree().
475 *
476 * This function initializes a pre-allocated struct ttm_buffer_object.
477 * As this object may be part of a larger structure, this function,
478 * together with the @destroy function,
479 * enables driver-specific objects derived from a ttm_buffer_object.
480 * On successful return, the object kref and list_kref are set to 1.
481 * If a failure occurs, the function will call the @destroy function, or
482 * kfree() if @destroy is NULL. Thus, after a failure, dereferencing @bo is
483 * illegal and will likely cause memory corruption.
484 *
485 * Returns
486 * -ENOMEM: Out of memory.
487 * -EINVAL: Invalid placement flags.
488 * -ERESTARTSYS: Interrupted by signal while sleeping waiting for resources.
489 */
490
491extern int ttm_bo_init(struct ttm_bo_device *bdev,
492 struct ttm_buffer_object *bo,
493 unsigned long size,
494 enum ttm_bo_type type,
495 struct ttm_placement *placement,
496 uint32_t page_alignment,
497 bool interrubtible,
498 struct file *persistent_swap_storage,
499 size_t acc_size,
500 struct sg_table *sg,
501 struct reservation_object *resv,
502 void (*destroy) (struct ttm_buffer_object *));
503
504/**
505 * ttm_bo_create
506 *
507 * @bdev: Pointer to a ttm_bo_device struct.
508 * @size: Requested size of buffer object.
509 * @type: Requested type of buffer object.
510 * @placement: Initial placement.
511 * @page_alignment: Data alignment in pages.
512 * @interruptible: If needing to sleep while waiting for GPU resources,
513 * sleep interruptible.
514 * @persistent_swap_storage: Usually the swap storage is deleted for buffers
515 * pinned in physical memory. If this behaviour is not desired, this member
516 * holds a pointer to a persistent shmem object. Typically, this would
517 * point to the shmem object backing a GEM object if TTM is used to back a
518 * GEM user interface.
519 * @p_bo: On successful completion *p_bo points to the created object.
520 *
521 * This function allocates a ttm_buffer_object, and then calls ttm_bo_init
522 * on that object. The destroy function is set to kfree().
523 * Returns
524 * -ENOMEM: Out of memory.
525 * -EINVAL: Invalid placement flags.
526 * -ERESTARTSYS: Interrupted by signal while waiting for resources.
527 */
528
529extern int ttm_bo_create(struct ttm_bo_device *bdev,
530 unsigned long size,
531 enum ttm_bo_type type,
532 struct ttm_placement *placement,
533 uint32_t page_alignment,
534 bool interruptible,
535 struct file *persistent_swap_storage,
536 struct ttm_buffer_object **p_bo);
537
538/**
539 * ttm_bo_init_mm
540 *
541 * @bdev: Pointer to a ttm_bo_device struct.
542 * @mem_type: The memory type.
543 * @p_size: size managed area in pages.
544 *
545 * Initialize a manager for a given memory type.
546 * Note: if part of driver firstopen, it must be protected from a
547 * potentially racing lastclose.
548 * Returns:
549 * -EINVAL: invalid size or memory type.
550 * -ENOMEM: Not enough memory.
551 * May also return driver-specified errors.
552 */
553
554extern int ttm_bo_init_mm(struct ttm_bo_device *bdev, unsigned type,
555 unsigned long p_size);
556/**
557 * ttm_bo_clean_mm
558 *
559 * @bdev: Pointer to a ttm_bo_device struct.
560 * @mem_type: The memory type.
561 *
562 * Take down a manager for a given memory type after first walking
563 * the LRU list to evict any buffers left alive.
564 *
565 * Normally, this function is part of lastclose() or unload(), and at that
566 * point there shouldn't be any buffers left created by user-space, since
567 * there should've been removed by the file descriptor release() method.
568 * However, before this function is run, make sure to signal all sync objects,
569 * and verify that the delayed delete queue is empty. The driver must also
570 * make sure that there are no NO_EVICT buffers present in this memory type
571 * when the call is made.
572 *
573 * If this function is part of a VT switch, the caller must make sure that
574 * there are no appications currently validating buffers before this
575 * function is called. The caller can do that by first taking the
576 * struct ttm_bo_device::ttm_lock in write mode.
577 *
578 * Returns:
579 * -EINVAL: invalid or uninitialized memory type.
580 * -EBUSY: There are still buffers left in this memory type.
581 */
582
583extern int ttm_bo_clean_mm(struct ttm_bo_device *bdev, unsigned mem_type);
584
585/**
586 * ttm_bo_evict_mm
587 *
588 * @bdev: Pointer to a ttm_bo_device struct.
589 * @mem_type: The memory type.
590 *
591 * Evicts all buffers on the lru list of the memory type.
592 * This is normally part of a VT switch or an
593 * out-of-memory-space-due-to-fragmentation handler.
594 * The caller must make sure that there are no other processes
595 * currently validating buffers, and can do that by taking the
596 * struct ttm_bo_device::ttm_lock in write mode.
597 *
598 * Returns:
599 * -EINVAL: Invalid or uninitialized memory type.
600 * -ERESTARTSYS: The call was interrupted by a signal while waiting to
601 * evict a buffer.
602 */
603
604extern int ttm_bo_evict_mm(struct ttm_bo_device *bdev, unsigned mem_type);
605
606/**
607 * ttm_kmap_obj_virtual
608 *
609 * @map: A struct ttm_bo_kmap_obj returned from ttm_bo_kmap.
610 * @is_iomem: Pointer to an integer that on return indicates 1 if the
611 * virtual map is io memory, 0 if normal memory.
612 *
613 * Returns the virtual address of a buffer object area mapped by ttm_bo_kmap.
614 * If *is_iomem is 1 on return, the virtual address points to an io memory area,
615 * that should strictly be accessed by the iowriteXX() and similar functions.
616 */
617
618static inline void *ttm_kmap_obj_virtual(struct ttm_bo_kmap_obj *map,
619 bool *is_iomem)
620{
621 *is_iomem = !!(map->bo_kmap_type & TTM_BO_MAP_IOMEM_MASK);
622 return map->virtual;
623}
624
625/**
626 * ttm_bo_kmap
627 *
628 * @bo: The buffer object.
629 * @start_page: The first page to map.
630 * @num_pages: Number of pages to map.
631 * @map: pointer to a struct ttm_bo_kmap_obj representing the map.
632 *
633 * Sets up a kernel virtual mapping, using ioremap, vmap or kmap to the
634 * data in the buffer object. The ttm_kmap_obj_virtual function can then be
635 * used to obtain a virtual address to the data.
636 *
637 * Returns
638 * -ENOMEM: Out of memory.
639 * -EINVAL: Invalid range.
640 */
641
642extern int ttm_bo_kmap(struct ttm_buffer_object *bo, unsigned long start_page,
643 unsigned long num_pages, struct ttm_bo_kmap_obj *map);
644
645/**
646 * ttm_bo_kunmap
647 *
648 * @map: Object describing the map to unmap.
649 *
650 * Unmaps a kernel map set up by ttm_bo_kmap.
651 */
652
653extern void ttm_bo_kunmap(struct ttm_bo_kmap_obj *map);
654
655/**
656 * ttm_fbdev_mmap - mmap fbdev memory backed by a ttm buffer object.
657 *
658 * @vma: vma as input from the fbdev mmap method.
659 * @bo: The bo backing the address space. The address space will
660 * have the same size as the bo, and start at offset 0.
661 *
662 * This function is intended to be called by the fbdev mmap method
663 * if the fbdev address space is to be backed by a bo.
664 */
665
666extern int ttm_fbdev_mmap(struct vm_area_struct *vma,
667 struct ttm_buffer_object *bo);
668
669/**
670 * ttm_bo_mmap - mmap out of the ttm device address space.
671 *
672 * @filp: filp as input from the mmap method.
673 * @vma: vma as input from the mmap method.
674 * @bdev: Pointer to the ttm_bo_device with the address space manager.
675 *
676 * This function is intended to be called by the device mmap method.
677 * if the device address space is to be backed by the bo manager.
678 */
679
680extern int ttm_bo_mmap(struct file *filp, struct vm_area_struct *vma,
681 struct ttm_bo_device *bdev);
682
683/**
684 * ttm_bo_io
685 *
686 * @bdev: Pointer to the struct ttm_bo_device.
687 * @filp: Pointer to the struct file attempting to read / write.
688 * @wbuf: User-space pointer to address of buffer to write. NULL on read.
689 * @rbuf: User-space pointer to address of buffer to read into.
690 * Null on write.
691 * @count: Number of bytes to read / write.
692 * @f_pos: Pointer to current file position.
693 * @write: 1 for read, 0 for write.
694 *
695 * This function implements read / write into ttm buffer objects, and is
696 * intended to
697 * be called from the fops::read and fops::write method.
698 * Returns:
699 * See man (2) write, man(2) read. In particular,
700 * the function may return -ERESTARTSYS if
701 * interrupted by a signal.
702 */
703
704extern ssize_t ttm_bo_io(struct ttm_bo_device *bdev, struct file *filp,
705 const char __user *wbuf, char __user *rbuf,
706 size_t count, loff_t *f_pos, bool write);
707
708extern void ttm_bo_swapout_all(struct ttm_bo_device *bdev);
709extern int ttm_bo_wait_unreserved(struct ttm_buffer_object *bo);
710#endif