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1/*
2 * Copyright 2020 Advanced Micro Devices, Inc.
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice shall be included in
12 * all copies or substantial portions of the Software.
13 *
14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
17 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
18 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20 * OTHER DEALINGS IN THE SOFTWARE.
21 *
22 * Authors: Christian König
23 */
24
25#ifndef _TTM_RESOURCE_H_
26#define _TTM_RESOURCE_H_
27
28#include <linux/types.h>
29#include <linux/list.h>
30#include <linux/mutex.h>
31#include <linux/iosys-map.h>
32#include <linux/dma-fence.h>
33
34#include <drm/drm_print.h>
35#include <drm/ttm/ttm_caching.h>
36#include <drm/ttm/ttm_kmap_iter.h>
37
38#define TTM_MAX_BO_PRIORITY 4U
39#define TTM_NUM_MEM_TYPES 8
40
41struct ttm_device;
42struct ttm_resource_manager;
43struct ttm_resource;
44struct ttm_place;
45struct ttm_buffer_object;
46struct ttm_placement;
47struct iosys_map;
48struct io_mapping;
49struct sg_table;
50struct scatterlist;
51
52struct ttm_resource_manager_func {
53 /**
54 * struct ttm_resource_manager_func member alloc
55 *
56 * @man: Pointer to a memory type manager.
57 * @bo: Pointer to the buffer object we're allocating space for.
58 * @place: Placement details.
59 * @res: Resulting pointer to the ttm_resource.
60 *
61 * This function should allocate space in the memory type managed
62 * by @man. Placement details if applicable are given by @place. If
63 * successful, a filled in ttm_resource object should be returned in
64 * @res. @res::start should be set to a value identifying the beginning
65 * of the range allocated, and the function should return zero.
66 * If the manager can't fulfill the request -ENOSPC should be returned.
67 * If a system error occurred, preventing the request to be fulfilled,
68 * the function should return a negative error code.
69 *
70 * This function may not be called from within atomic context and needs
71 * to take care of its own locking to protect any data structures
72 * managing the space.
73 */
74 int (*alloc)(struct ttm_resource_manager *man,
75 struct ttm_buffer_object *bo,
76 const struct ttm_place *place,
77 struct ttm_resource **res);
78
79 /**
80 * struct ttm_resource_manager_func member free
81 *
82 * @man: Pointer to a memory type manager.
83 * @res: Pointer to a struct ttm_resource to be freed.
84 *
85 * This function frees memory type resources previously allocated.
86 * May not be called from within atomic context.
87 */
88 void (*free)(struct ttm_resource_manager *man,
89 struct ttm_resource *res);
90
91 /**
92 * struct ttm_resource_manager_func member intersects
93 *
94 * @man: Pointer to a memory type manager.
95 * @res: Pointer to a struct ttm_resource to be checked.
96 * @place: Placement to check against.
97 * @size: Size of the check.
98 *
99 * Test if @res intersects with @place + @size. Used to judge if
100 * evictions are valueable or not.
101 */
102 bool (*intersects)(struct ttm_resource_manager *man,
103 struct ttm_resource *res,
104 const struct ttm_place *place,
105 size_t size);
106
107 /**
108 * struct ttm_resource_manager_func member compatible
109 *
110 * @man: Pointer to a memory type manager.
111 * @res: Pointer to a struct ttm_resource to be checked.
112 * @place: Placement to check against.
113 * @size: Size of the check.
114 *
115 * Test if @res compatible with @place + @size. Used to check of
116 * the need to move the backing store or not.
117 */
118 bool (*compatible)(struct ttm_resource_manager *man,
119 struct ttm_resource *res,
120 const struct ttm_place *place,
121 size_t size);
122
123 /**
124 * struct ttm_resource_manager_func member debug
125 *
126 * @man: Pointer to a memory type manager.
127 * @printer: Prefix to be used in printout to identify the caller.
128 *
129 * This function is called to print out the state of the memory
130 * type manager to aid debugging of out-of-memory conditions.
131 * It may not be called from within atomic context.
132 */
133 void (*debug)(struct ttm_resource_manager *man,
134 struct drm_printer *printer);
135};
136
137/**
138 * struct ttm_resource_manager
139 *
140 * @use_type: The memory type is enabled.
141 * @use_tt: If a TT object should be used for the backing store.
142 * @size: Size of the managed region.
143 * @bdev: ttm device this manager belongs to
144 * @func: structure pointer implementing the range manager. See above
145 * @move_lock: lock for move fence
146 * @move: The fence of the last pipelined move operation.
147 * @lru: The lru list for this memory type.
148 *
149 * This structure is used to identify and manage memory types for a device.
150 */
151struct ttm_resource_manager {
152 /*
153 * No protection. Constant from start.
154 */
155 bool use_type;
156 bool use_tt;
157 struct ttm_device *bdev;
158 uint64_t size;
159 const struct ttm_resource_manager_func *func;
160 spinlock_t move_lock;
161
162 /*
163 * Protected by @move_lock.
164 */
165 struct dma_fence *move;
166
167 /*
168 * Protected by the bdev->lru_lock.
169 */
170 struct list_head lru[TTM_MAX_BO_PRIORITY];
171
172 /**
173 * @usage: How much of the resources are used, protected by the
174 * bdev->lru_lock.
175 */
176 uint64_t usage;
177};
178
179/**
180 * struct ttm_bus_placement
181 *
182 * @addr: mapped virtual address
183 * @offset: physical addr
184 * @is_iomem: is this io memory ?
185 * @caching: See enum ttm_caching
186 *
187 * Structure indicating the bus placement of an object.
188 */
189struct ttm_bus_placement {
190 void *addr;
191 phys_addr_t offset;
192 bool is_iomem;
193 enum ttm_caching caching;
194};
195
196/**
197 * struct ttm_resource
198 *
199 * @start: Start of the allocation.
200 * @size: Actual size of resource in bytes.
201 * @mem_type: Resource type of the allocation.
202 * @placement: Placement flags.
203 * @bus: Placement on io bus accessible to the CPU
204 * @bo: weak reference to the BO, protected by ttm_device::lru_lock
205 *
206 * Structure indicating the placement and space resources used by a
207 * buffer object.
208 */
209struct ttm_resource {
210 unsigned long start;
211 size_t size;
212 uint32_t mem_type;
213 uint32_t placement;
214 struct ttm_bus_placement bus;
215 struct ttm_buffer_object *bo;
216
217 /**
218 * @lru: Least recently used list, see &ttm_resource_manager.lru
219 */
220 struct list_head lru;
221};
222
223/**
224 * struct ttm_resource_cursor
225 *
226 * @priority: the current priority
227 *
228 * Cursor to iterate over the resources in a manager.
229 */
230struct ttm_resource_cursor {
231 unsigned int priority;
232};
233
234/**
235 * struct ttm_lru_bulk_move_pos
236 *
237 * @first: first res in the bulk move range
238 * @last: last res in the bulk move range
239 *
240 * Range of resources for a lru bulk move.
241 */
242struct ttm_lru_bulk_move_pos {
243 struct ttm_resource *first;
244 struct ttm_resource *last;
245};
246
247/**
248 * struct ttm_lru_bulk_move
249 *
250 * @pos: first/last lru entry for resources in the each domain/priority
251 *
252 * Container for the current bulk move state. Should be used with
253 * ttm_lru_bulk_move_init() and ttm_bo_set_bulk_move().
254 */
255struct ttm_lru_bulk_move {
256 struct ttm_lru_bulk_move_pos pos[TTM_NUM_MEM_TYPES][TTM_MAX_BO_PRIORITY];
257};
258
259/**
260 * struct ttm_kmap_iter_iomap - Specialization for a struct io_mapping +
261 * struct sg_table backed struct ttm_resource.
262 * @base: Embedded struct ttm_kmap_iter providing the usage interface.
263 * @iomap: struct io_mapping representing the underlying linear io_memory.
264 * @st: sg_table into @iomap, representing the memory of the struct ttm_resource.
265 * @start: Offset that needs to be subtracted from @st to make
266 * sg_dma_address(st->sgl) - @start == 0 for @iomap start.
267 * @cache: Scatterlist traversal cache for fast lookups.
268 * @cache.sg: Pointer to the currently cached scatterlist segment.
269 * @cache.i: First index of @sg. PAGE_SIZE granularity.
270 * @cache.end: Last index + 1 of @sg. PAGE_SIZE granularity.
271 * @cache.offs: First offset into @iomap of @sg. PAGE_SIZE granularity.
272 */
273struct ttm_kmap_iter_iomap {
274 struct ttm_kmap_iter base;
275 struct io_mapping *iomap;
276 struct sg_table *st;
277 resource_size_t start;
278 struct {
279 struct scatterlist *sg;
280 pgoff_t i;
281 pgoff_t end;
282 pgoff_t offs;
283 } cache;
284};
285
286/**
287 * struct ttm_kmap_iter_linear_io - Iterator specialization for linear io
288 * @base: The base iterator
289 * @dmap: Points to the starting address of the region
290 * @needs_unmap: Whether we need to unmap on fini
291 */
292struct ttm_kmap_iter_linear_io {
293 struct ttm_kmap_iter base;
294 struct iosys_map dmap;
295 bool needs_unmap;
296};
297
298/**
299 * ttm_resource_manager_set_used
300 *
301 * @man: A memory manager object.
302 * @used: usage state to set.
303 *
304 * Set the manager in use flag. If disabled the manager is no longer
305 * used for object placement.
306 */
307static inline void
308ttm_resource_manager_set_used(struct ttm_resource_manager *man, bool used)
309{
310 int i;
311
312 for (i = 0; i < TTM_MAX_BO_PRIORITY; i++)
313 WARN_ON(!list_empty(&man->lru[i]));
314 man->use_type = used;
315}
316
317/**
318 * ttm_resource_manager_used
319 *
320 * @man: Manager to get used state for
321 *
322 * Get the in use flag for a manager.
323 * Returns:
324 * true is used, false if not.
325 */
326static inline bool ttm_resource_manager_used(struct ttm_resource_manager *man)
327{
328 return man->use_type;
329}
330
331/**
332 * ttm_resource_manager_cleanup
333 *
334 * @man: A memory manager object.
335 *
336 * Cleanup the move fences from the memory manager object.
337 */
338static inline void
339ttm_resource_manager_cleanup(struct ttm_resource_manager *man)
340{
341 dma_fence_put(man->move);
342 man->move = NULL;
343}
344
345void ttm_lru_bulk_move_init(struct ttm_lru_bulk_move *bulk);
346void ttm_lru_bulk_move_tail(struct ttm_lru_bulk_move *bulk);
347
348void ttm_resource_add_bulk_move(struct ttm_resource *res,
349 struct ttm_buffer_object *bo);
350void ttm_resource_del_bulk_move(struct ttm_resource *res,
351 struct ttm_buffer_object *bo);
352void ttm_resource_move_to_lru_tail(struct ttm_resource *res);
353
354void ttm_resource_init(struct ttm_buffer_object *bo,
355 const struct ttm_place *place,
356 struct ttm_resource *res);
357void ttm_resource_fini(struct ttm_resource_manager *man,
358 struct ttm_resource *res);
359
360int ttm_resource_alloc(struct ttm_buffer_object *bo,
361 const struct ttm_place *place,
362 struct ttm_resource **res);
363void ttm_resource_free(struct ttm_buffer_object *bo, struct ttm_resource **res);
364bool ttm_resource_intersects(struct ttm_device *bdev,
365 struct ttm_resource *res,
366 const struct ttm_place *place,
367 size_t size);
368bool ttm_resource_compatible(struct ttm_device *bdev,
369 struct ttm_resource *res,
370 const struct ttm_place *place,
371 size_t size);
372bool ttm_resource_compat(struct ttm_resource *res,
373 struct ttm_placement *placement);
374void ttm_resource_set_bo(struct ttm_resource *res,
375 struct ttm_buffer_object *bo);
376
377void ttm_resource_manager_init(struct ttm_resource_manager *man,
378 struct ttm_device *bdev,
379 uint64_t size);
380
381int ttm_resource_manager_evict_all(struct ttm_device *bdev,
382 struct ttm_resource_manager *man);
383
384uint64_t ttm_resource_manager_usage(struct ttm_resource_manager *man);
385void ttm_resource_manager_debug(struct ttm_resource_manager *man,
386 struct drm_printer *p);
387
388struct ttm_resource *
389ttm_resource_manager_first(struct ttm_resource_manager *man,
390 struct ttm_resource_cursor *cursor);
391struct ttm_resource *
392ttm_resource_manager_next(struct ttm_resource_manager *man,
393 struct ttm_resource_cursor *cursor,
394 struct ttm_resource *res);
395
396/**
397 * ttm_resource_manager_for_each_res - iterate over all resources
398 * @man: the resource manager
399 * @cursor: struct ttm_resource_cursor for the current position
400 * @res: the current resource
401 *
402 * Iterate over all the evictable resources in a resource manager.
403 */
404#define ttm_resource_manager_for_each_res(man, cursor, res) \
405 for (res = ttm_resource_manager_first(man, cursor); res; \
406 res = ttm_resource_manager_next(man, cursor, res))
407
408struct ttm_kmap_iter *
409ttm_kmap_iter_iomap_init(struct ttm_kmap_iter_iomap *iter_io,
410 struct io_mapping *iomap,
411 struct sg_table *st,
412 resource_size_t start);
413
414struct ttm_kmap_iter_linear_io;
415
416struct ttm_kmap_iter *
417ttm_kmap_iter_linear_io_init(struct ttm_kmap_iter_linear_io *iter_io,
418 struct ttm_device *bdev,
419 struct ttm_resource *mem);
420
421void ttm_kmap_iter_linear_io_fini(struct ttm_kmap_iter_linear_io *iter_io,
422 struct ttm_device *bdev,
423 struct ttm_resource *mem);
424
425void ttm_resource_manager_create_debugfs(struct ttm_resource_manager *man,
426 struct dentry * parent,
427 const char *name);
428#endif
1/*
2 * Copyright 2020 Advanced Micro Devices, Inc.
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice shall be included in
12 * all copies or substantial portions of the Software.
13 *
14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
17 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
18 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20 * OTHER DEALINGS IN THE SOFTWARE.
21 *
22 * Authors: Christian König
23 */
24
25#ifndef _TTM_RESOURCE_H_
26#define _TTM_RESOURCE_H_
27
28#include <linux/types.h>
29#include <linux/mutex.h>
30#include <linux/dma-buf-map.h>
31#include <linux/dma-fence.h>
32#include <drm/drm_print.h>
33#include <drm/ttm/ttm_caching.h>
34#include <drm/ttm/ttm_kmap_iter.h>
35
36#define TTM_MAX_BO_PRIORITY 4U
37
38struct ttm_device;
39struct ttm_resource_manager;
40struct ttm_resource;
41struct ttm_place;
42struct ttm_buffer_object;
43struct dma_buf_map;
44struct io_mapping;
45struct sg_table;
46struct scatterlist;
47
48struct ttm_resource_manager_func {
49 /**
50 * struct ttm_resource_manager_func member alloc
51 *
52 * @man: Pointer to a memory type manager.
53 * @bo: Pointer to the buffer object we're allocating space for.
54 * @place: Placement details.
55 * @res: Resulting pointer to the ttm_resource.
56 *
57 * This function should allocate space in the memory type managed
58 * by @man. Placement details if applicable are given by @place. If
59 * successful, a filled in ttm_resource object should be returned in
60 * @res. @res::start should be set to a value identifying the beginning
61 * of the range allocated, and the function should return zero.
62 * If the manager can't fulfill the request -ENOSPC should be returned.
63 * If a system error occurred, preventing the request to be fulfilled,
64 * the function should return a negative error code.
65 *
66 * This function may not be called from within atomic context and needs
67 * to take care of its own locking to protect any data structures
68 * managing the space.
69 */
70 int (*alloc)(struct ttm_resource_manager *man,
71 struct ttm_buffer_object *bo,
72 const struct ttm_place *place,
73 struct ttm_resource **res);
74
75 /**
76 * struct ttm_resource_manager_func member free
77 *
78 * @man: Pointer to a memory type manager.
79 * @res: Pointer to a struct ttm_resource to be freed.
80 *
81 * This function frees memory type resources previously allocated.
82 * May not be called from within atomic context.
83 */
84 void (*free)(struct ttm_resource_manager *man,
85 struct ttm_resource *res);
86
87 /**
88 * struct ttm_resource_manager_func member debug
89 *
90 * @man: Pointer to a memory type manager.
91 * @printer: Prefix to be used in printout to identify the caller.
92 *
93 * This function is called to print out the state of the memory
94 * type manager to aid debugging of out-of-memory conditions.
95 * It may not be called from within atomic context.
96 */
97 void (*debug)(struct ttm_resource_manager *man,
98 struct drm_printer *printer);
99};
100
101/**
102 * struct ttm_resource_manager
103 *
104 * @use_type: The memory type is enabled.
105 * @flags: TTM_MEMTYPE_XX flags identifying the traits of the memory
106 * managed by this memory type.
107 * @gpu_offset: If used, the GPU offset of the first managed page of
108 * fixed memory or the first managed location in an aperture.
109 * @size: Size of the managed region.
110 * @func: structure pointer implementing the range manager. See above
111 * @move_lock: lock for move fence
112 * static information. bdev::driver::io_mem_free is never used.
113 * @lru: The lru list for this memory type.
114 * @move: The fence of the last pipelined move operation.
115 *
116 * This structure is used to identify and manage memory types for a device.
117 */
118struct ttm_resource_manager {
119 /*
120 * No protection. Constant from start.
121 */
122 bool use_type;
123 bool use_tt;
124 uint64_t size;
125 const struct ttm_resource_manager_func *func;
126 spinlock_t move_lock;
127
128 /*
129 * Protected by the global->lru_lock.
130 */
131
132 struct list_head lru[TTM_MAX_BO_PRIORITY];
133
134 /*
135 * Protected by @move_lock.
136 */
137 struct dma_fence *move;
138};
139
140/**
141 * struct ttm_bus_placement
142 *
143 * @addr: mapped virtual address
144 * @offset: physical addr
145 * @is_iomem: is this io memory ?
146 *
147 * Structure indicating the bus placement of an object.
148 */
149struct ttm_bus_placement {
150 void *addr;
151 phys_addr_t offset;
152 bool is_iomem;
153 enum ttm_caching caching;
154};
155
156/**
157 * struct ttm_resource
158 *
159 * @start: Start of the allocation.
160 * @num_pages: Actual size of resource in pages.
161 * @mem_type: Resource type of the allocation.
162 * @placement: Placement flags.
163 * @bus: Placement on io bus accessible to the CPU
164 *
165 * Structure indicating the placement and space resources used by a
166 * buffer object.
167 */
168struct ttm_resource {
169 unsigned long start;
170 unsigned long num_pages;
171 uint32_t mem_type;
172 uint32_t placement;
173 struct ttm_bus_placement bus;
174};
175
176/**
177 * struct ttm_kmap_iter_iomap - Specialization for a struct io_mapping +
178 * struct sg_table backed struct ttm_resource.
179 * @base: Embedded struct ttm_kmap_iter providing the usage interface.
180 * @iomap: struct io_mapping representing the underlying linear io_memory.
181 * @st: sg_table into @iomap, representing the memory of the struct ttm_resource.
182 * @start: Offset that needs to be subtracted from @st to make
183 * sg_dma_address(st->sgl) - @start == 0 for @iomap start.
184 * @cache: Scatterlist traversal cache for fast lookups.
185 * @cache.sg: Pointer to the currently cached scatterlist segment.
186 * @cache.i: First index of @sg. PAGE_SIZE granularity.
187 * @cache.end: Last index + 1 of @sg. PAGE_SIZE granularity.
188 * @cache.offs: First offset into @iomap of @sg. PAGE_SIZE granularity.
189 */
190struct ttm_kmap_iter_iomap {
191 struct ttm_kmap_iter base;
192 struct io_mapping *iomap;
193 struct sg_table *st;
194 resource_size_t start;
195 struct {
196 struct scatterlist *sg;
197 pgoff_t i;
198 pgoff_t end;
199 pgoff_t offs;
200 } cache;
201};
202
203/**
204 * struct ttm_kmap_iter_linear_io - Iterator specialization for linear io
205 * @base: The base iterator
206 * @dmap: Points to the starting address of the region
207 * @needs_unmap: Whether we need to unmap on fini
208 */
209struct ttm_kmap_iter_linear_io {
210 struct ttm_kmap_iter base;
211 struct dma_buf_map dmap;
212 bool needs_unmap;
213};
214
215/**
216 * ttm_resource_manager_set_used
217 *
218 * @man: A memory manager object.
219 * @used: usage state to set.
220 *
221 * Set the manager in use flag. If disabled the manager is no longer
222 * used for object placement.
223 */
224static inline void
225ttm_resource_manager_set_used(struct ttm_resource_manager *man, bool used)
226{
227 int i;
228
229 for (i = 0; i < TTM_MAX_BO_PRIORITY; i++)
230 WARN_ON(!list_empty(&man->lru[i]));
231 man->use_type = used;
232}
233
234/**
235 * ttm_resource_manager_used
236 *
237 * @man: Manager to get used state for
238 *
239 * Get the in use flag for a manager.
240 * Returns:
241 * true is used, false if not.
242 */
243static inline bool ttm_resource_manager_used(struct ttm_resource_manager *man)
244{
245 return man->use_type;
246}
247
248/**
249 * ttm_resource_manager_cleanup
250 *
251 * @man: A memory manager object.
252 *
253 * Cleanup the move fences from the memory manager object.
254 */
255static inline void
256ttm_resource_manager_cleanup(struct ttm_resource_manager *man)
257{
258 dma_fence_put(man->move);
259 man->move = NULL;
260}
261
262void ttm_resource_init(struct ttm_buffer_object *bo,
263 const struct ttm_place *place,
264 struct ttm_resource *res);
265int ttm_resource_alloc(struct ttm_buffer_object *bo,
266 const struct ttm_place *place,
267 struct ttm_resource **res);
268void ttm_resource_free(struct ttm_buffer_object *bo, struct ttm_resource **res);
269
270void ttm_resource_manager_init(struct ttm_resource_manager *man,
271 unsigned long p_size);
272
273int ttm_resource_manager_evict_all(struct ttm_device *bdev,
274 struct ttm_resource_manager *man);
275
276void ttm_resource_manager_debug(struct ttm_resource_manager *man,
277 struct drm_printer *p);
278
279struct ttm_kmap_iter *
280ttm_kmap_iter_iomap_init(struct ttm_kmap_iter_iomap *iter_io,
281 struct io_mapping *iomap,
282 struct sg_table *st,
283 resource_size_t start);
284
285struct ttm_kmap_iter_linear_io;
286
287struct ttm_kmap_iter *
288ttm_kmap_iter_linear_io_init(struct ttm_kmap_iter_linear_io *iter_io,
289 struct ttm_device *bdev,
290 struct ttm_resource *mem);
291
292void ttm_kmap_iter_linear_io_fini(struct ttm_kmap_iter_linear_io *iter_io,
293 struct ttm_device *bdev,
294 struct ttm_resource *mem);
295#endif