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 #define pr_fmt(fmt) "[TTM] " fmt
29
30 #include "ttm/ttm_memory.h"
31 #include "ttm/ttm_module.h"
32 #include "ttm/ttm_page_alloc.h"
33 #include <linux/spinlock.h>
34 #include <linux/sched.h>
35 #include <linux/wait.h>
36 #include <linux/mm.h>
37 #include <linux/module.h>
38 #include <linux/slab.h>
39
40 #define TTM_MEMORY_ALLOC_RETRIES 4
41
42 struct ttm_mem_zone {
43 struct kobject kobj;
44 struct ttm_mem_global *glob;
45 const char *name;
46 uint64_t zone_mem;
47 uint64_t emer_mem;
48 uint64_t max_mem;
49 uint64_t swap_limit;
50 uint64_t used_mem;
51 };
52
53 static struct attribute ttm_mem_sys = {
54 .name = "zone_memory",
55 .mode = S_IRUGO
56 };
57 static struct attribute ttm_mem_emer = {
58 .name = "emergency_memory",
59 .mode = S_IRUGO | S_IWUSR
60 };
61 static struct attribute ttm_mem_max = {
62 .name = "available_memory",
63 .mode = S_IRUGO | S_IWUSR
64 };
65 static struct attribute ttm_mem_swap = {
66 .name = "swap_limit",
67 .mode = S_IRUGO | S_IWUSR
68 };
69 static struct attribute ttm_mem_used = {
70 .name = "used_memory",
71 .mode = S_IRUGO
72 };
73
ttm_mem_zone_kobj_release(struct kobject * kobj)74 static void ttm_mem_zone_kobj_release(struct kobject *kobj)
75 {
76 struct ttm_mem_zone *zone =
77 container_of(kobj, struct ttm_mem_zone, kobj);
78
79 pr_info("Zone %7s: Used memory at exit: %llu kiB\n",
80 zone->name, (unsigned long long)zone->used_mem >> 10);
81 kfree(zone);
82 }
83
ttm_mem_zone_show(struct kobject * kobj,struct attribute * attr,char * buffer)84 static ssize_t ttm_mem_zone_show(struct kobject *kobj,
85 struct attribute *attr,
86 char *buffer)
87 {
88 struct ttm_mem_zone *zone =
89 container_of(kobj, struct ttm_mem_zone, kobj);
90 uint64_t val = 0;
91
92 spin_lock(&zone->glob->lock);
93 if (attr == &ttm_mem_sys)
94 val = zone->zone_mem;
95 else if (attr == &ttm_mem_emer)
96 val = zone->emer_mem;
97 else if (attr == &ttm_mem_max)
98 val = zone->max_mem;
99 else if (attr == &ttm_mem_swap)
100 val = zone->swap_limit;
101 else if (attr == &ttm_mem_used)
102 val = zone->used_mem;
103 spin_unlock(&zone->glob->lock);
104
105 return snprintf(buffer, PAGE_SIZE, "%llu\n",
106 (unsigned long long) val >> 10);
107 }
108
109 static void ttm_check_swapping(struct ttm_mem_global *glob);
110
ttm_mem_zone_store(struct kobject * kobj,struct attribute * attr,const char * buffer,size_t size)111 static ssize_t ttm_mem_zone_store(struct kobject *kobj,
112 struct attribute *attr,
113 const char *buffer,
114 size_t size)
115 {
116 struct ttm_mem_zone *zone =
117 container_of(kobj, struct ttm_mem_zone, kobj);
118 int chars;
119 unsigned long val;
120 uint64_t val64;
121
122 chars = sscanf(buffer, "%lu", &val);
123 if (chars == 0)
124 return size;
125
126 val64 = val;
127 val64 <<= 10;
128
129 spin_lock(&zone->glob->lock);
130 if (val64 > zone->zone_mem)
131 val64 = zone->zone_mem;
132 if (attr == &ttm_mem_emer) {
133 zone->emer_mem = val64;
134 if (zone->max_mem > val64)
135 zone->max_mem = val64;
136 } else if (attr == &ttm_mem_max) {
137 zone->max_mem = val64;
138 if (zone->emer_mem < val64)
139 zone->emer_mem = val64;
140 } else if (attr == &ttm_mem_swap)
141 zone->swap_limit = val64;
142 spin_unlock(&zone->glob->lock);
143
144 ttm_check_swapping(zone->glob);
145
146 return size;
147 }
148
149 static struct attribute *ttm_mem_zone_attrs[] = {
150 &ttm_mem_sys,
151 &ttm_mem_emer,
152 &ttm_mem_max,
153 &ttm_mem_swap,
154 &ttm_mem_used,
155 NULL
156 };
157
158 static const struct sysfs_ops ttm_mem_zone_ops = {
159 .show = &ttm_mem_zone_show,
160 .store = &ttm_mem_zone_store
161 };
162
163 static struct kobj_type ttm_mem_zone_kobj_type = {
164 .release = &ttm_mem_zone_kobj_release,
165 .sysfs_ops = &ttm_mem_zone_ops,
166 .default_attrs = ttm_mem_zone_attrs,
167 };
168
ttm_mem_global_kobj_release(struct kobject * kobj)169 static void ttm_mem_global_kobj_release(struct kobject *kobj)
170 {
171 struct ttm_mem_global *glob =
172 container_of(kobj, struct ttm_mem_global, kobj);
173
174 kfree(glob);
175 }
176
177 static struct kobj_type ttm_mem_glob_kobj_type = {
178 .release = &ttm_mem_global_kobj_release,
179 };
180
ttm_zones_above_swap_target(struct ttm_mem_global * glob,bool from_wq,uint64_t extra)181 static bool ttm_zones_above_swap_target(struct ttm_mem_global *glob,
182 bool from_wq, uint64_t extra)
183 {
184 unsigned int i;
185 struct ttm_mem_zone *zone;
186 uint64_t target;
187
188 for (i = 0; i < glob->num_zones; ++i) {
189 zone = glob->zones[i];
190
191 if (from_wq)
192 target = zone->swap_limit;
193 else if (capable(CAP_SYS_ADMIN))
194 target = zone->emer_mem;
195 else
196 target = zone->max_mem;
197
198 target = (extra > target) ? 0ULL : target;
199
200 if (zone->used_mem > target)
201 return true;
202 }
203 return false;
204 }
205
206 /**
207 * At this point we only support a single shrink callback.
208 * Extend this if needed, perhaps using a linked list of callbacks.
209 * Note that this function is reentrant:
210 * many threads may try to swap out at any given time.
211 */
212
ttm_shrink(struct ttm_mem_global * glob,bool from_wq,uint64_t extra)213 static void ttm_shrink(struct ttm_mem_global *glob, bool from_wq,
214 uint64_t extra)
215 {
216 int ret;
217 struct ttm_mem_shrink *shrink;
218
219 spin_lock(&glob->lock);
220 if (glob->shrink == NULL)
221 goto out;
222
223 while (ttm_zones_above_swap_target(glob, from_wq, extra)) {
224 shrink = glob->shrink;
225 spin_unlock(&glob->lock);
226 ret = shrink->do_shrink(shrink);
227 spin_lock(&glob->lock);
228 if (unlikely(ret != 0))
229 goto out;
230 }
231 out:
232 spin_unlock(&glob->lock);
233 }
234
235
236
ttm_shrink_work(struct work_struct * work)237 static void ttm_shrink_work(struct work_struct *work)
238 {
239 struct ttm_mem_global *glob =
240 container_of(work, struct ttm_mem_global, work);
241
242 ttm_shrink(glob, true, 0ULL);
243 }
244
ttm_mem_init_kernel_zone(struct ttm_mem_global * glob,const struct sysinfo * si)245 static int ttm_mem_init_kernel_zone(struct ttm_mem_global *glob,
246 const struct sysinfo *si)
247 {
248 struct ttm_mem_zone *zone = kzalloc(sizeof(*zone), GFP_KERNEL);
249 uint64_t mem;
250 int ret;
251
252 if (unlikely(!zone))
253 return -ENOMEM;
254
255 mem = si->totalram - si->totalhigh;
256 mem *= si->mem_unit;
257
258 zone->name = "kernel";
259 zone->zone_mem = mem;
260 zone->max_mem = mem >> 1;
261 zone->emer_mem = (mem >> 1) + (mem >> 2);
262 zone->swap_limit = zone->max_mem - (mem >> 3);
263 zone->used_mem = 0;
264 zone->glob = glob;
265 glob->zone_kernel = zone;
266 ret = kobject_init_and_add(
267 &zone->kobj, &ttm_mem_zone_kobj_type, &glob->kobj, zone->name);
268 if (unlikely(ret != 0)) {
269 kobject_put(&zone->kobj);
270 return ret;
271 }
272 glob->zones[glob->num_zones++] = zone;
273 return 0;
274 }
275
276 #ifdef CONFIG_HIGHMEM
ttm_mem_init_highmem_zone(struct ttm_mem_global * glob,const struct sysinfo * si)277 static int ttm_mem_init_highmem_zone(struct ttm_mem_global *glob,
278 const struct sysinfo *si)
279 {
280 struct ttm_mem_zone *zone;
281 uint64_t mem;
282 int ret;
283
284 if (si->totalhigh == 0)
285 return 0;
286
287 zone = kzalloc(sizeof(*zone), GFP_KERNEL);
288 if (unlikely(!zone))
289 return -ENOMEM;
290
291 mem = si->totalram;
292 mem *= si->mem_unit;
293
294 zone->name = "highmem";
295 zone->zone_mem = mem;
296 zone->max_mem = mem >> 1;
297 zone->emer_mem = (mem >> 1) + (mem >> 2);
298 zone->swap_limit = zone->max_mem - (mem >> 3);
299 zone->used_mem = 0;
300 zone->glob = glob;
301 glob->zone_highmem = zone;
302 ret = kobject_init_and_add(
303 &zone->kobj, &ttm_mem_zone_kobj_type, &glob->kobj, zone->name);
304 if (unlikely(ret != 0)) {
305 kobject_put(&zone->kobj);
306 return ret;
307 }
308 glob->zones[glob->num_zones++] = zone;
309 return 0;
310 }
311 #else
ttm_mem_init_dma32_zone(struct ttm_mem_global * glob,const struct sysinfo * si)312 static int ttm_mem_init_dma32_zone(struct ttm_mem_global *glob,
313 const struct sysinfo *si)
314 {
315 struct ttm_mem_zone *zone = kzalloc(sizeof(*zone), GFP_KERNEL);
316 uint64_t mem;
317 int ret;
318
319 if (unlikely(!zone))
320 return -ENOMEM;
321
322 mem = si->totalram;
323 mem *= si->mem_unit;
324
325 /**
326 * No special dma32 zone needed.
327 */
328
329 if (mem <= ((uint64_t) 1ULL << 32)) {
330 kfree(zone);
331 return 0;
332 }
333
334 /*
335 * Limit max dma32 memory to 4GB for now
336 * until we can figure out how big this
337 * zone really is.
338 */
339
340 mem = ((uint64_t) 1ULL << 32);
341 zone->name = "dma32";
342 zone->zone_mem = mem;
343 zone->max_mem = mem >> 1;
344 zone->emer_mem = (mem >> 1) + (mem >> 2);
345 zone->swap_limit = zone->max_mem - (mem >> 3);
346 zone->used_mem = 0;
347 zone->glob = glob;
348 glob->zone_dma32 = zone;
349 ret = kobject_init_and_add(
350 &zone->kobj, &ttm_mem_zone_kobj_type, &glob->kobj, zone->name);
351 if (unlikely(ret != 0)) {
352 kobject_put(&zone->kobj);
353 return ret;
354 }
355 glob->zones[glob->num_zones++] = zone;
356 return 0;
357 }
358 #endif
359
ttm_mem_global_init(struct ttm_mem_global * glob)360 int ttm_mem_global_init(struct ttm_mem_global *glob)
361 {
362 struct sysinfo si;
363 int ret;
364 int i;
365 struct ttm_mem_zone *zone;
366
367 spin_lock_init(&glob->lock);
368 glob->swap_queue = create_singlethread_workqueue("ttm_swap");
369 INIT_WORK(&glob->work, ttm_shrink_work);
370 init_waitqueue_head(&glob->queue);
371 ret = kobject_init_and_add(
372 &glob->kobj, &ttm_mem_glob_kobj_type, ttm_get_kobj(), "memory_accounting");
373 if (unlikely(ret != 0)) {
374 kobject_put(&glob->kobj);
375 return ret;
376 }
377
378 si_meminfo(&si);
379
380 ret = ttm_mem_init_kernel_zone(glob, &si);
381 if (unlikely(ret != 0))
382 goto out_no_zone;
383 #ifdef CONFIG_HIGHMEM
384 ret = ttm_mem_init_highmem_zone(glob, &si);
385 if (unlikely(ret != 0))
386 goto out_no_zone;
387 #else
388 ret = ttm_mem_init_dma32_zone(glob, &si);
389 if (unlikely(ret != 0))
390 goto out_no_zone;
391 #endif
392 for (i = 0; i < glob->num_zones; ++i) {
393 zone = glob->zones[i];
394 pr_info("Zone %7s: Available graphics memory: %llu kiB\n",
395 zone->name, (unsigned long long)zone->max_mem >> 10);
396 }
397 ttm_page_alloc_init(glob, glob->zone_kernel->max_mem/(2*PAGE_SIZE));
398 ttm_dma_page_alloc_init(glob, glob->zone_kernel->max_mem/(2*PAGE_SIZE));
399 return 0;
400 out_no_zone:
401 ttm_mem_global_release(glob);
402 return ret;
403 }
404 EXPORT_SYMBOL(ttm_mem_global_init);
405
ttm_mem_global_release(struct ttm_mem_global * glob)406 void ttm_mem_global_release(struct ttm_mem_global *glob)
407 {
408 unsigned int i;
409 struct ttm_mem_zone *zone;
410
411 /* let the page allocator first stop the shrink work. */
412 ttm_page_alloc_fini();
413 ttm_dma_page_alloc_fini();
414
415 flush_workqueue(glob->swap_queue);
416 destroy_workqueue(glob->swap_queue);
417 glob->swap_queue = NULL;
418 for (i = 0; i < glob->num_zones; ++i) {
419 zone = glob->zones[i];
420 kobject_del(&zone->kobj);
421 kobject_put(&zone->kobj);
422 }
423 kobject_del(&glob->kobj);
424 kobject_put(&glob->kobj);
425 }
426 EXPORT_SYMBOL(ttm_mem_global_release);
427
ttm_check_swapping(struct ttm_mem_global * glob)428 static void ttm_check_swapping(struct ttm_mem_global *glob)
429 {
430 bool needs_swapping = false;
431 unsigned int i;
432 struct ttm_mem_zone *zone;
433
434 spin_lock(&glob->lock);
435 for (i = 0; i < glob->num_zones; ++i) {
436 zone = glob->zones[i];
437 if (zone->used_mem > zone->swap_limit) {
438 needs_swapping = true;
439 break;
440 }
441 }
442
443 spin_unlock(&glob->lock);
444
445 if (unlikely(needs_swapping))
446 (void)queue_work(glob->swap_queue, &glob->work);
447
448 }
449
ttm_mem_global_free_zone(struct ttm_mem_global * glob,struct ttm_mem_zone * single_zone,uint64_t amount)450 static void ttm_mem_global_free_zone(struct ttm_mem_global *glob,
451 struct ttm_mem_zone *single_zone,
452 uint64_t amount)
453 {
454 unsigned int i;
455 struct ttm_mem_zone *zone;
456
457 spin_lock(&glob->lock);
458 for (i = 0; i < glob->num_zones; ++i) {
459 zone = glob->zones[i];
460 if (single_zone && zone != single_zone)
461 continue;
462 zone->used_mem -= amount;
463 }
464 spin_unlock(&glob->lock);
465 }
466
ttm_mem_global_free(struct ttm_mem_global * glob,uint64_t amount)467 void ttm_mem_global_free(struct ttm_mem_global *glob,
468 uint64_t amount)
469 {
470 return ttm_mem_global_free_zone(glob, NULL, amount);
471 }
472 EXPORT_SYMBOL(ttm_mem_global_free);
473
ttm_mem_global_reserve(struct ttm_mem_global * glob,struct ttm_mem_zone * single_zone,uint64_t amount,bool reserve)474 static int ttm_mem_global_reserve(struct ttm_mem_global *glob,
475 struct ttm_mem_zone *single_zone,
476 uint64_t amount, bool reserve)
477 {
478 uint64_t limit;
479 int ret = -ENOMEM;
480 unsigned int i;
481 struct ttm_mem_zone *zone;
482
483 spin_lock(&glob->lock);
484 for (i = 0; i < glob->num_zones; ++i) {
485 zone = glob->zones[i];
486 if (single_zone && zone != single_zone)
487 continue;
488
489 limit = (capable(CAP_SYS_ADMIN)) ?
490 zone->emer_mem : zone->max_mem;
491
492 if (zone->used_mem > limit)
493 goto out_unlock;
494 }
495
496 if (reserve) {
497 for (i = 0; i < glob->num_zones; ++i) {
498 zone = glob->zones[i];
499 if (single_zone && zone != single_zone)
500 continue;
501 zone->used_mem += amount;
502 }
503 }
504
505 ret = 0;
506 out_unlock:
507 spin_unlock(&glob->lock);
508 ttm_check_swapping(glob);
509
510 return ret;
511 }
512
513
ttm_mem_global_alloc_zone(struct ttm_mem_global * glob,struct ttm_mem_zone * single_zone,uint64_t memory,bool no_wait,bool interruptible)514 static int ttm_mem_global_alloc_zone(struct ttm_mem_global *glob,
515 struct ttm_mem_zone *single_zone,
516 uint64_t memory,
517 bool no_wait, bool interruptible)
518 {
519 int count = TTM_MEMORY_ALLOC_RETRIES;
520
521 while (unlikely(ttm_mem_global_reserve(glob,
522 single_zone,
523 memory, true)
524 != 0)) {
525 if (no_wait)
526 return -ENOMEM;
527 if (unlikely(count-- == 0))
528 return -ENOMEM;
529 ttm_shrink(glob, false, memory + (memory >> 2) + 16);
530 }
531
532 return 0;
533 }
534
ttm_mem_global_alloc(struct ttm_mem_global * glob,uint64_t memory,bool no_wait,bool interruptible)535 int ttm_mem_global_alloc(struct ttm_mem_global *glob, uint64_t memory,
536 bool no_wait, bool interruptible)
537 {
538 /**
539 * Normal allocations of kernel memory are registered in
540 * all zones.
541 */
542
543 return ttm_mem_global_alloc_zone(glob, NULL, memory, no_wait,
544 interruptible);
545 }
546 EXPORT_SYMBOL(ttm_mem_global_alloc);
547
ttm_mem_global_alloc_page(struct ttm_mem_global * glob,struct page * page,bool no_wait,bool interruptible)548 int ttm_mem_global_alloc_page(struct ttm_mem_global *glob,
549 struct page *page,
550 bool no_wait, bool interruptible)
551 {
552
553 struct ttm_mem_zone *zone = NULL;
554
555 /**
556 * Page allocations may be registed in a single zone
557 * only if highmem or !dma32.
558 */
559
560 #ifdef CONFIG_HIGHMEM
561 if (PageHighMem(page) && glob->zone_highmem != NULL)
562 zone = glob->zone_highmem;
563 #else
564 if (glob->zone_dma32 && page_to_pfn(page) > 0x00100000UL)
565 zone = glob->zone_kernel;
566 #endif
567 return ttm_mem_global_alloc_zone(glob, zone, PAGE_SIZE, no_wait,
568 interruptible);
569 }
570
ttm_mem_global_free_page(struct ttm_mem_global * glob,struct page * page)571 void ttm_mem_global_free_page(struct ttm_mem_global *glob, struct page *page)
572 {
573 struct ttm_mem_zone *zone = NULL;
574
575 #ifdef CONFIG_HIGHMEM
576 if (PageHighMem(page) && glob->zone_highmem != NULL)
577 zone = glob->zone_highmem;
578 #else
579 if (glob->zone_dma32 && page_to_pfn(page) > 0x00100000UL)
580 zone = glob->zone_kernel;
581 #endif
582 ttm_mem_global_free_zone(glob, zone, PAGE_SIZE);
583 }
584
585
ttm_round_pot(size_t size)586 size_t ttm_round_pot(size_t size)
587 {
588 if ((size & (size - 1)) == 0)
589 return size;
590 else if (size > PAGE_SIZE)
591 return PAGE_ALIGN(size);
592 else {
593 size_t tmp_size = 4;
594
595 while (tmp_size < size)
596 tmp_size <<= 1;
597
598 return tmp_size;
599 }
600 return 0;
601 }
602 EXPORT_SYMBOL(ttm_round_pot);
603