1 | /************************************************************************** |
2 | * |
3 | * Copyright 2006-2008 Tungsten Graphics, Inc., Cedar Park, TX. USA. |
4 | * Copyright 2016 Intel Corporation |
5 | * All Rights Reserved. |
6 | * |
7 | * Permission is hereby granted, free of charge, to any person obtaining a |
8 | * copy of this software and associated documentation files (the |
9 | * "Software"), to deal in the Software without restriction, including |
10 | * without limitation the rights to use, copy, modify, merge, publish, |
11 | * distribute, sub license, and/or sell copies of the Software, and to |
12 | * permit persons to whom the Software is furnished to do so, subject to |
13 | * the following conditions: |
14 | * |
15 | * The above copyright notice and this permission notice (including the |
16 | * next paragraph) shall be included in all copies or substantial portions |
17 | * of the Software. |
18 | * |
19 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
20 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
21 | * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL |
22 | * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, |
23 | * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR |
24 | * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE |
25 | * USE OR OTHER DEALINGS IN THE SOFTWARE. |
26 | * |
27 | * |
28 | **************************************************************************/ |
29 | /* |
30 | * Authors: |
31 | * Thomas Hellstrom <thomas-at-tungstengraphics-dot-com> |
32 | */ |
33 | |
34 | #ifndef _DRM_MM_H_ |
35 | #define _DRM_MM_H_ |
36 | |
37 | /* |
38 | * Generic range manager structs |
39 | */ |
40 | #include <linux/bug.h> |
41 | #include <linux/rbtree.h> |
42 | #include <linux/limits.h> |
43 | #include <linux/mm_types.h> |
44 | #include <linux/list.h> |
45 | #include <linux/spinlock.h> |
46 | #ifdef CONFIG_DRM_DEBUG_MM |
47 | #include <linux/stackdepot.h> |
48 | #endif |
49 | #include <linux/types.h> |
50 | |
51 | #include <drm/drm_print.h> |
52 | |
53 | #ifdef CONFIG_DRM_DEBUG_MM |
54 | #define DRM_MM_BUG_ON(expr) BUG_ON(expr) |
55 | #else |
56 | #define DRM_MM_BUG_ON(expr) BUILD_BUG_ON_INVALID(expr) |
57 | #endif |
58 | |
59 | /** |
60 | * enum drm_mm_insert_mode - control search and allocation behaviour |
61 | * |
62 | * The &struct drm_mm range manager supports finding a suitable modes using |
63 | * a number of search trees. These trees are oranised by size, by address and |
64 | * in most recent eviction order. This allows the user to find either the |
65 | * smallest hole to reuse, the lowest or highest address to reuse, or simply |
66 | * reuse the most recent eviction that fits. When allocating the &drm_mm_node |
67 | * from within the hole, the &drm_mm_insert_mode also dictate whether to |
68 | * allocate the lowest matching address or the highest. |
69 | */ |
70 | enum drm_mm_insert_mode { |
71 | /** |
72 | * @DRM_MM_INSERT_BEST: |
73 | * |
74 | * Search for the smallest hole (within the search range) that fits |
75 | * the desired node. |
76 | * |
77 | * Allocates the node from the bottom of the found hole. |
78 | */ |
79 | DRM_MM_INSERT_BEST = 0, |
80 | |
81 | /** |
82 | * @DRM_MM_INSERT_LOW: |
83 | * |
84 | * Search for the lowest hole (address closest to 0, within the search |
85 | * range) that fits the desired node. |
86 | * |
87 | * Allocates the node from the bottom of the found hole. |
88 | */ |
89 | DRM_MM_INSERT_LOW, |
90 | |
91 | /** |
92 | * @DRM_MM_INSERT_HIGH: |
93 | * |
94 | * Search for the highest hole (address closest to U64_MAX, within the |
95 | * search range) that fits the desired node. |
96 | * |
97 | * Allocates the node from the *top* of the found hole. The specified |
98 | * alignment for the node is applied to the base of the node |
99 | * (&drm_mm_node.start). |
100 | */ |
101 | DRM_MM_INSERT_HIGH, |
102 | |
103 | /** |
104 | * @DRM_MM_INSERT_EVICT: |
105 | * |
106 | * Search for the most recently evicted hole (within the search range) |
107 | * that fits the desired node. This is appropriate for use immediately |
108 | * after performing an eviction scan (see drm_mm_scan_init()) and |
109 | * removing the selected nodes to form a hole. |
110 | * |
111 | * Allocates the node from the bottom of the found hole. |
112 | */ |
113 | DRM_MM_INSERT_EVICT, |
114 | |
115 | /** |
116 | * @DRM_MM_INSERT_ONCE: |
117 | * |
118 | * Only check the first hole for suitablity and report -ENOSPC |
119 | * immediately otherwise, rather than check every hole until a |
120 | * suitable one is found. Can only be used in conjunction with another |
121 | * search method such as DRM_MM_INSERT_HIGH or DRM_MM_INSERT_LOW. |
122 | */ |
123 | DRM_MM_INSERT_ONCE = BIT(31), |
124 | |
125 | /** |
126 | * @DRM_MM_INSERT_HIGHEST: |
127 | * |
128 | * Only check the highest hole (the hole with the largest address) and |
129 | * insert the node at the top of the hole or report -ENOSPC if |
130 | * unsuitable. |
131 | * |
132 | * Does not search all holes. |
133 | */ |
134 | DRM_MM_INSERT_HIGHEST = DRM_MM_INSERT_HIGH | DRM_MM_INSERT_ONCE, |
135 | |
136 | /** |
137 | * @DRM_MM_INSERT_LOWEST: |
138 | * |
139 | * Only check the lowest hole (the hole with the smallest address) and |
140 | * insert the node at the bottom of the hole or report -ENOSPC if |
141 | * unsuitable. |
142 | * |
143 | * Does not search all holes. |
144 | */ |
145 | DRM_MM_INSERT_LOWEST = DRM_MM_INSERT_LOW | DRM_MM_INSERT_ONCE, |
146 | }; |
147 | |
148 | /** |
149 | * struct drm_mm_node - allocated block in the DRM allocator |
150 | * |
151 | * This represents an allocated block in a &drm_mm allocator. Except for |
152 | * pre-reserved nodes inserted using drm_mm_reserve_node() the structure is |
153 | * entirely opaque and should only be accessed through the provided funcions. |
154 | * Since allocation of these nodes is entirely handled by the driver they can be |
155 | * embedded. |
156 | */ |
157 | struct drm_mm_node { |
158 | /** @color: Opaque driver-private tag. */ |
159 | unsigned long color; |
160 | /** @start: Start address of the allocated block. */ |
161 | u64 start; |
162 | /** @size: Size of the allocated block. */ |
163 | u64 size; |
164 | /* private: */ |
165 | struct drm_mm *mm; |
166 | struct list_head node_list; |
167 | struct list_head hole_stack; |
168 | struct rb_node rb; |
169 | struct rb_node rb_hole_size; |
170 | struct rb_node rb_hole_addr; |
171 | u64 __subtree_last; |
172 | u64 hole_size; |
173 | u64 subtree_max_hole; |
174 | unsigned long flags; |
175 | #define DRM_MM_NODE_ALLOCATED_BIT 0 |
176 | #define DRM_MM_NODE_SCANNED_BIT 1 |
177 | #ifdef CONFIG_DRM_DEBUG_MM |
178 | depot_stack_handle_t stack; |
179 | #endif |
180 | }; |
181 | |
182 | /** |
183 | * struct drm_mm - DRM allocator |
184 | * |
185 | * DRM range allocator with a few special functions and features geared towards |
186 | * managing GPU memory. Except for the @color_adjust callback the structure is |
187 | * entirely opaque and should only be accessed through the provided functions |
188 | * and macros. This structure can be embedded into larger driver structures. |
189 | */ |
190 | struct drm_mm { |
191 | /** |
192 | * @color_adjust: |
193 | * |
194 | * Optional driver callback to further apply restrictions on a hole. The |
195 | * node argument points at the node containing the hole from which the |
196 | * block would be allocated (see drm_mm_hole_follows() and friends). The |
197 | * other arguments are the size of the block to be allocated. The driver |
198 | * can adjust the start and end as needed to e.g. insert guard pages. |
199 | */ |
200 | void (*color_adjust)(const struct drm_mm_node *node, |
201 | unsigned long color, |
202 | u64 *start, u64 *end); |
203 | |
204 | /* private: */ |
205 | /* List of all memory nodes that immediately precede a free hole. */ |
206 | struct list_head hole_stack; |
207 | /* head_node.node_list is the list of all memory nodes, ordered |
208 | * according to the (increasing) start address of the memory node. */ |
209 | struct drm_mm_node head_node; |
210 | /* Keep an interval_tree for fast lookup of drm_mm_nodes by address. */ |
211 | struct rb_root_cached interval_tree; |
212 | struct rb_root_cached holes_size; |
213 | struct rb_root holes_addr; |
214 | |
215 | unsigned long scan_active; |
216 | }; |
217 | |
218 | /** |
219 | * struct drm_mm_scan - DRM allocator eviction roaster data |
220 | * |
221 | * This structure tracks data needed for the eviction roaster set up using |
222 | * drm_mm_scan_init(), and used with drm_mm_scan_add_block() and |
223 | * drm_mm_scan_remove_block(). The structure is entirely opaque and should only |
224 | * be accessed through the provided functions and macros. It is meant to be |
225 | * allocated temporarily by the driver on the stack. |
226 | */ |
227 | struct drm_mm_scan { |
228 | /* private: */ |
229 | struct drm_mm *mm; |
230 | |
231 | u64 size; |
232 | u64 alignment; |
233 | u64 remainder_mask; |
234 | |
235 | u64 range_start; |
236 | u64 range_end; |
237 | |
238 | u64 hit_start; |
239 | u64 hit_end; |
240 | |
241 | unsigned long color; |
242 | enum drm_mm_insert_mode mode; |
243 | }; |
244 | |
245 | /** |
246 | * drm_mm_node_allocated - checks whether a node is allocated |
247 | * @node: drm_mm_node to check |
248 | * |
249 | * Drivers are required to clear a node prior to using it with the |
250 | * drm_mm range manager. |
251 | * |
252 | * Drivers should use this helper for proper encapsulation of drm_mm |
253 | * internals. |
254 | * |
255 | * Returns: |
256 | * True if the @node is allocated. |
257 | */ |
258 | static inline bool drm_mm_node_allocated(const struct drm_mm_node *node) |
259 | { |
260 | return test_bit(DRM_MM_NODE_ALLOCATED_BIT, &node->flags); |
261 | } |
262 | |
263 | /** |
264 | * drm_mm_initialized - checks whether an allocator is initialized |
265 | * @mm: drm_mm to check |
266 | * |
267 | * Drivers should clear the struct drm_mm prior to initialisation if they |
268 | * want to use this function. |
269 | * |
270 | * Drivers should use this helper for proper encapsulation of drm_mm |
271 | * internals. |
272 | * |
273 | * Returns: |
274 | * True if the @mm is initialized. |
275 | */ |
276 | static inline bool drm_mm_initialized(const struct drm_mm *mm) |
277 | { |
278 | return READ_ONCE(mm->hole_stack.next); |
279 | } |
280 | |
281 | /** |
282 | * drm_mm_hole_follows - checks whether a hole follows this node |
283 | * @node: drm_mm_node to check |
284 | * |
285 | * Holes are embedded into the drm_mm using the tail of a drm_mm_node. |
286 | * If you wish to know whether a hole follows this particular node, |
287 | * query this function. See also drm_mm_hole_node_start() and |
288 | * drm_mm_hole_node_end(). |
289 | * |
290 | * Returns: |
291 | * True if a hole follows the @node. |
292 | */ |
293 | static inline bool drm_mm_hole_follows(const struct drm_mm_node *node) |
294 | { |
295 | return node->hole_size; |
296 | } |
297 | |
298 | static inline u64 __drm_mm_hole_node_start(const struct drm_mm_node *hole_node) |
299 | { |
300 | return hole_node->start + hole_node->size; |
301 | } |
302 | |
303 | /** |
304 | * drm_mm_hole_node_start - computes the start of the hole following @node |
305 | * @hole_node: drm_mm_node which implicitly tracks the following hole |
306 | * |
307 | * This is useful for driver-specific debug dumpers. Otherwise drivers should |
308 | * not inspect holes themselves. Drivers must check first whether a hole indeed |
309 | * follows by looking at drm_mm_hole_follows() |
310 | * |
311 | * Returns: |
312 | * Start of the subsequent hole. |
313 | */ |
314 | static inline u64 drm_mm_hole_node_start(const struct drm_mm_node *hole_node) |
315 | { |
316 | DRM_MM_BUG_ON(!drm_mm_hole_follows(hole_node)); |
317 | return __drm_mm_hole_node_start(hole_node); |
318 | } |
319 | |
320 | static inline u64 __drm_mm_hole_node_end(const struct drm_mm_node *hole_node) |
321 | { |
322 | return list_next_entry(hole_node, node_list)->start; |
323 | } |
324 | |
325 | /** |
326 | * drm_mm_hole_node_end - computes the end of the hole following @node |
327 | * @hole_node: drm_mm_node which implicitly tracks the following hole |
328 | * |
329 | * This is useful for driver-specific debug dumpers. Otherwise drivers should |
330 | * not inspect holes themselves. Drivers must check first whether a hole indeed |
331 | * follows by looking at drm_mm_hole_follows(). |
332 | * |
333 | * Returns: |
334 | * End of the subsequent hole. |
335 | */ |
336 | static inline u64 drm_mm_hole_node_end(const struct drm_mm_node *hole_node) |
337 | { |
338 | return __drm_mm_hole_node_end(hole_node); |
339 | } |
340 | |
341 | /** |
342 | * drm_mm_nodes - list of nodes under the drm_mm range manager |
343 | * @mm: the struct drm_mm range manager |
344 | * |
345 | * As the drm_mm range manager hides its node_list deep with its |
346 | * structure, extracting it looks painful and repetitive. This is |
347 | * not expected to be used outside of the drm_mm_for_each_node() |
348 | * macros and similar internal functions. |
349 | * |
350 | * Returns: |
351 | * The node list, may be empty. |
352 | */ |
353 | #define drm_mm_nodes(mm) (&(mm)->head_node.node_list) |
354 | |
355 | /** |
356 | * drm_mm_for_each_node - iterator to walk over all allocated nodes |
357 | * @entry: &struct drm_mm_node to assign to in each iteration step |
358 | * @mm: &drm_mm allocator to walk |
359 | * |
360 | * This iterator walks over all nodes in the range allocator. It is implemented |
361 | * with list_for_each(), so not save against removal of elements. |
362 | */ |
363 | #define drm_mm_for_each_node(entry, mm) \ |
364 | list_for_each_entry(entry, drm_mm_nodes(mm), node_list) |
365 | |
366 | /** |
367 | * drm_mm_for_each_node_safe - iterator to walk over all allocated nodes |
368 | * @entry: &struct drm_mm_node to assign to in each iteration step |
369 | * @next: &struct drm_mm_node to store the next step |
370 | * @mm: &drm_mm allocator to walk |
371 | * |
372 | * This iterator walks over all nodes in the range allocator. It is implemented |
373 | * with list_for_each_safe(), so save against removal of elements. |
374 | */ |
375 | #define drm_mm_for_each_node_safe(entry, next, mm) \ |
376 | list_for_each_entry_safe(entry, next, drm_mm_nodes(mm), node_list) |
377 | |
378 | /** |
379 | * drm_mm_for_each_hole - iterator to walk over all holes |
380 | * @pos: &drm_mm_node used internally to track progress |
381 | * @mm: &drm_mm allocator to walk |
382 | * @hole_start: ulong variable to assign the hole start to on each iteration |
383 | * @hole_end: ulong variable to assign the hole end to on each iteration |
384 | * |
385 | * This iterator walks over all holes in the range allocator. It is implemented |
386 | * with list_for_each(), so not save against removal of elements. @entry is used |
387 | * internally and will not reflect a real drm_mm_node for the very first hole. |
388 | * Hence users of this iterator may not access it. |
389 | * |
390 | * Implementation Note: |
391 | * We need to inline list_for_each_entry in order to be able to set hole_start |
392 | * and hole_end on each iteration while keeping the macro sane. |
393 | */ |
394 | #define drm_mm_for_each_hole(pos, mm, hole_start, hole_end) \ |
395 | for (pos = list_first_entry(&(mm)->hole_stack, \ |
396 | typeof(*pos), hole_stack); \ |
397 | &pos->hole_stack != &(mm)->hole_stack ? \ |
398 | hole_start = drm_mm_hole_node_start(pos), \ |
399 | hole_end = hole_start + pos->hole_size, \ |
400 | 1 : 0; \ |
401 | pos = list_next_entry(pos, hole_stack)) |
402 | |
403 | /* |
404 | * Basic range manager support (drm_mm.c) |
405 | */ |
406 | int drm_mm_reserve_node(struct drm_mm *mm, struct drm_mm_node *node); |
407 | int drm_mm_insert_node_in_range(struct drm_mm *mm, |
408 | struct drm_mm_node *node, |
409 | u64 size, |
410 | u64 alignment, |
411 | unsigned long color, |
412 | u64 start, |
413 | u64 end, |
414 | enum drm_mm_insert_mode mode); |
415 | |
416 | /** |
417 | * drm_mm_insert_node_generic - search for space and insert @node |
418 | * @mm: drm_mm to allocate from |
419 | * @node: preallocate node to insert |
420 | * @size: size of the allocation |
421 | * @alignment: alignment of the allocation |
422 | * @color: opaque tag value to use for this node |
423 | * @mode: fine-tune the allocation search and placement |
424 | * |
425 | * This is a simplified version of drm_mm_insert_node_in_range() with no |
426 | * range restrictions applied. |
427 | * |
428 | * The preallocated node must be cleared to 0. |
429 | * |
430 | * Returns: |
431 | * 0 on success, -ENOSPC if there's no suitable hole. |
432 | */ |
433 | static inline int |
434 | drm_mm_insert_node_generic(struct drm_mm *mm, struct drm_mm_node *node, |
435 | u64 size, u64 alignment, |
436 | unsigned long color, |
437 | enum drm_mm_insert_mode mode) |
438 | { |
439 | return drm_mm_insert_node_in_range(mm, node, |
440 | size, alignment, color, |
441 | 0, U64_MAX, mode); |
442 | } |
443 | |
444 | /** |
445 | * drm_mm_insert_node - search for space and insert @node |
446 | * @mm: drm_mm to allocate from |
447 | * @node: preallocate node to insert |
448 | * @size: size of the allocation |
449 | * |
450 | * This is a simplified version of drm_mm_insert_node_generic() with @color set |
451 | * to 0. |
452 | * |
453 | * The preallocated node must be cleared to 0. |
454 | * |
455 | * Returns: |
456 | * 0 on success, -ENOSPC if there's no suitable hole. |
457 | */ |
458 | static inline int drm_mm_insert_node(struct drm_mm *mm, |
459 | struct drm_mm_node *node, |
460 | u64 size) |
461 | { |
462 | return drm_mm_insert_node_generic(mm, node, size, 0, 0, 0); |
463 | } |
464 | |
465 | void drm_mm_remove_node(struct drm_mm_node *node); |
466 | void drm_mm_replace_node(struct drm_mm_node *old, struct drm_mm_node *new); |
467 | void drm_mm_init(struct drm_mm *mm, u64 start, u64 size); |
468 | void drm_mm_takedown(struct drm_mm *mm); |
469 | |
470 | /** |
471 | * drm_mm_clean - checks whether an allocator is clean |
472 | * @mm: drm_mm allocator to check |
473 | * |
474 | * Returns: |
475 | * True if the allocator is completely free, false if there's still a node |
476 | * allocated in it. |
477 | */ |
478 | static inline bool drm_mm_clean(const struct drm_mm *mm) |
479 | { |
480 | return list_empty(drm_mm_nodes(mm)); |
481 | } |
482 | |
483 | struct drm_mm_node * |
484 | __drm_mm_interval_first(const struct drm_mm *mm, u64 start, u64 last); |
485 | |
486 | /** |
487 | * drm_mm_for_each_node_in_range - iterator to walk over a range of |
488 | * allocated nodes |
489 | * @node__: drm_mm_node structure to assign to in each iteration step |
490 | * @mm__: drm_mm allocator to walk |
491 | * @start__: starting offset, the first node will overlap this |
492 | * @end__: ending offset, the last node will start before this (but may overlap) |
493 | * |
494 | * This iterator walks over all nodes in the range allocator that lie |
495 | * between @start and @end. It is implemented similarly to list_for_each(), |
496 | * but using the internal interval tree to accelerate the search for the |
497 | * starting node, and so not safe against removal of elements. It assumes |
498 | * that @end is within (or is the upper limit of) the drm_mm allocator. |
499 | * If [@start, @end] are beyond the range of the drm_mm, the iterator may walk |
500 | * over the special _unallocated_ &drm_mm.head_node, and may even continue |
501 | * indefinitely. |
502 | */ |
503 | #define drm_mm_for_each_node_in_range(node__, mm__, start__, end__) \ |
504 | for (node__ = __drm_mm_interval_first((mm__), (start__), (end__)-1); \ |
505 | node__->start < (end__); \ |
506 | node__ = list_next_entry(node__, node_list)) |
507 | |
508 | void drm_mm_scan_init_with_range(struct drm_mm_scan *scan, |
509 | struct drm_mm *mm, |
510 | u64 size, u64 alignment, unsigned long color, |
511 | u64 start, u64 end, |
512 | enum drm_mm_insert_mode mode); |
513 | |
514 | /** |
515 | * drm_mm_scan_init - initialize lru scanning |
516 | * @scan: scan state |
517 | * @mm: drm_mm to scan |
518 | * @size: size of the allocation |
519 | * @alignment: alignment of the allocation |
520 | * @color: opaque tag value to use for the allocation |
521 | * @mode: fine-tune the allocation search and placement |
522 | * |
523 | * This is a simplified version of drm_mm_scan_init_with_range() with no range |
524 | * restrictions applied. |
525 | * |
526 | * This simply sets up the scanning routines with the parameters for the desired |
527 | * hole. |
528 | * |
529 | * Warning: |
530 | * As long as the scan list is non-empty, no other operations than |
531 | * adding/removing nodes to/from the scan list are allowed. |
532 | */ |
533 | static inline void drm_mm_scan_init(struct drm_mm_scan *scan, |
534 | struct drm_mm *mm, |
535 | u64 size, |
536 | u64 alignment, |
537 | unsigned long color, |
538 | enum drm_mm_insert_mode mode) |
539 | { |
540 | drm_mm_scan_init_with_range(scan, mm, |
541 | size, alignment, color, |
542 | 0, U64_MAX, mode); |
543 | } |
544 | |
545 | bool drm_mm_scan_add_block(struct drm_mm_scan *scan, |
546 | struct drm_mm_node *node); |
547 | bool drm_mm_scan_remove_block(struct drm_mm_scan *scan, |
548 | struct drm_mm_node *node); |
549 | struct drm_mm_node *drm_mm_scan_color_evict(struct drm_mm_scan *scan); |
550 | |
551 | void drm_mm_print(const struct drm_mm *mm, struct drm_printer *p); |
552 | |
553 | #endif |
554 | |