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7
8#include <linux/iova.h>
9#include <linux/module.h>
10#include <linux/slab.h>
11#include <linux/smp.h>
12#include <linux/bitops.h>
13#include <linux/cpu.h>
14
15
16#define IOVA_ANCHOR ~0UL
17
18static bool iova_rcache_insert(struct iova_domain *iovad,
19 unsigned long pfn,
20 unsigned long size);
21static unsigned long iova_rcache_get(struct iova_domain *iovad,
22 unsigned long size,
23 unsigned long limit_pfn);
24static void init_iova_rcaches(struct iova_domain *iovad);
25static void free_cpu_cached_iovas(unsigned int cpu, struct iova_domain *iovad);
26static void free_iova_rcaches(struct iova_domain *iovad);
27static void fq_destroy_all_entries(struct iova_domain *iovad);
28static void fq_flush_timeout(struct timer_list *t);
29
30static int iova_cpuhp_dead(unsigned int cpu, struct hlist_node *node)
31{
32 struct iova_domain *iovad;
33
34 iovad = hlist_entry_safe(node, struct iova_domain, cpuhp_dead);
35
36 free_cpu_cached_iovas(cpu, iovad);
37 return 0;
38}
39
40static void free_global_cached_iovas(struct iova_domain *iovad);
41
42static struct iova *to_iova(struct rb_node *node)
43{
44 return rb_entry(node, struct iova, node);
45}
46
47void
48init_iova_domain(struct iova_domain *iovad, unsigned long granule,
49 unsigned long start_pfn)
50{
51
52
53
54
55
56 BUG_ON((granule > PAGE_SIZE) || !is_power_of_2(granule));
57
58 spin_lock_init(&iovad->iova_rbtree_lock);
59 iovad->rbroot = RB_ROOT;
60 iovad->cached_node = &iovad->anchor.node;
61 iovad->cached32_node = &iovad->anchor.node;
62 iovad->granule = granule;
63 iovad->start_pfn = start_pfn;
64 iovad->dma_32bit_pfn = 1UL << (32 - iova_shift(iovad));
65 iovad->max32_alloc_size = iovad->dma_32bit_pfn;
66 iovad->flush_cb = NULL;
67 iovad->fq = NULL;
68 iovad->anchor.pfn_lo = iovad->anchor.pfn_hi = IOVA_ANCHOR;
69 rb_link_node(&iovad->anchor.node, NULL, &iovad->rbroot.rb_node);
70 rb_insert_color(&iovad->anchor.node, &iovad->rbroot);
71 cpuhp_state_add_instance_nocalls(CPUHP_IOMMU_IOVA_DEAD, &iovad->cpuhp_dead);
72 init_iova_rcaches(iovad);
73}
74EXPORT_SYMBOL_GPL(init_iova_domain);
75
76static bool has_iova_flush_queue(struct iova_domain *iovad)
77{
78 return !!iovad->fq;
79}
80
81static void free_iova_flush_queue(struct iova_domain *iovad)
82{
83 if (!has_iova_flush_queue(iovad))
84 return;
85
86 if (timer_pending(&iovad->fq_timer))
87 del_timer(&iovad->fq_timer);
88
89 fq_destroy_all_entries(iovad);
90
91 free_percpu(iovad->fq);
92
93 iovad->fq = NULL;
94 iovad->flush_cb = NULL;
95 iovad->entry_dtor = NULL;
96}
97
98int init_iova_flush_queue(struct iova_domain *iovad,
99 iova_flush_cb flush_cb, iova_entry_dtor entry_dtor)
100{
101 struct iova_fq __percpu *queue;
102 int cpu;
103
104 atomic64_set(&iovad->fq_flush_start_cnt, 0);
105 atomic64_set(&iovad->fq_flush_finish_cnt, 0);
106
107 queue = alloc_percpu(struct iova_fq);
108 if (!queue)
109 return -ENOMEM;
110
111 iovad->flush_cb = flush_cb;
112 iovad->entry_dtor = entry_dtor;
113
114 for_each_possible_cpu(cpu) {
115 struct iova_fq *fq;
116
117 fq = per_cpu_ptr(queue, cpu);
118 fq->head = 0;
119 fq->tail = 0;
120
121 spin_lock_init(&fq->lock);
122 }
123
124 iovad->fq = queue;
125
126 timer_setup(&iovad->fq_timer, fq_flush_timeout, 0);
127 atomic_set(&iovad->fq_timer_on, 0);
128
129 return 0;
130}
131
132static struct rb_node *
133__get_cached_rbnode(struct iova_domain *iovad, unsigned long limit_pfn)
134{
135 if (limit_pfn <= iovad->dma_32bit_pfn)
136 return iovad->cached32_node;
137
138 return iovad->cached_node;
139}
140
141static void
142__cached_rbnode_insert_update(struct iova_domain *iovad, struct iova *new)
143{
144 if (new->pfn_hi < iovad->dma_32bit_pfn)
145 iovad->cached32_node = &new->node;
146 else
147 iovad->cached_node = &new->node;
148}
149
150static void
151__cached_rbnode_delete_update(struct iova_domain *iovad, struct iova *free)
152{
153 struct iova *cached_iova;
154
155 cached_iova = to_iova(iovad->cached32_node);
156 if (free == cached_iova ||
157 (free->pfn_hi < iovad->dma_32bit_pfn &&
158 free->pfn_lo >= cached_iova->pfn_lo)) {
159 iovad->cached32_node = rb_next(&free->node);
160 iovad->max32_alloc_size = iovad->dma_32bit_pfn;
161 }
162
163 cached_iova = to_iova(iovad->cached_node);
164 if (free->pfn_lo >= cached_iova->pfn_lo)
165 iovad->cached_node = rb_next(&free->node);
166}
167
168static struct rb_node *iova_find_limit(struct iova_domain *iovad, unsigned long limit_pfn)
169{
170 struct rb_node *node, *next;
171
172
173
174
175
176
177
178
179 if (limit_pfn > iovad->dma_32bit_pfn)
180 return &iovad->anchor.node;
181
182 node = iovad->rbroot.rb_node;
183 while (to_iova(node)->pfn_hi < limit_pfn)
184 node = node->rb_right;
185
186search_left:
187 while (node->rb_left && to_iova(node->rb_left)->pfn_lo >= limit_pfn)
188 node = node->rb_left;
189
190 if (!node->rb_left)
191 return node;
192
193 next = node->rb_left;
194 while (next->rb_right) {
195 next = next->rb_right;
196 if (to_iova(next)->pfn_lo >= limit_pfn) {
197 node = next;
198 goto search_left;
199 }
200 }
201
202 return node;
203}
204
205
206static void
207iova_insert_rbtree(struct rb_root *root, struct iova *iova,
208 struct rb_node *start)
209{
210 struct rb_node **new, *parent = NULL;
211
212 new = (start) ? &start : &(root->rb_node);
213
214 while (*new) {
215 struct iova *this = to_iova(*new);
216
217 parent = *new;
218
219 if (iova->pfn_lo < this->pfn_lo)
220 new = &((*new)->rb_left);
221 else if (iova->pfn_lo > this->pfn_lo)
222 new = &((*new)->rb_right);
223 else {
224 WARN_ON(1);
225 return;
226 }
227 }
228
229 rb_link_node(&iova->node, parent, new);
230 rb_insert_color(&iova->node, root);
231}
232
233static int __alloc_and_insert_iova_range(struct iova_domain *iovad,
234 unsigned long size, unsigned long limit_pfn,
235 struct iova *new, bool size_aligned)
236{
237 struct rb_node *curr, *prev;
238 struct iova *curr_iova;
239 unsigned long flags;
240 unsigned long new_pfn, retry_pfn;
241 unsigned long align_mask = ~0UL;
242 unsigned long high_pfn = limit_pfn, low_pfn = iovad->start_pfn;
243
244 if (size_aligned)
245 align_mask <<= fls_long(size - 1);
246
247
248 spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
249 if (limit_pfn <= iovad->dma_32bit_pfn &&
250 size >= iovad->max32_alloc_size)
251 goto iova32_full;
252
253 curr = __get_cached_rbnode(iovad, limit_pfn);
254 curr_iova = to_iova(curr);
255 retry_pfn = curr_iova->pfn_hi + 1;
256
257retry:
258 do {
259 high_pfn = min(high_pfn, curr_iova->pfn_lo);
260 new_pfn = (high_pfn - size) & align_mask;
261 prev = curr;
262 curr = rb_prev(curr);
263 curr_iova = to_iova(curr);
264 } while (curr && new_pfn <= curr_iova->pfn_hi && new_pfn >= low_pfn);
265
266 if (high_pfn < size || new_pfn < low_pfn) {
267 if (low_pfn == iovad->start_pfn && retry_pfn < limit_pfn) {
268 high_pfn = limit_pfn;
269 low_pfn = retry_pfn;
270 curr = iova_find_limit(iovad, limit_pfn);
271 curr_iova = to_iova(curr);
272 goto retry;
273 }
274 iovad->max32_alloc_size = size;
275 goto iova32_full;
276 }
277
278
279 new->pfn_lo = new_pfn;
280 new->pfn_hi = new->pfn_lo + size - 1;
281
282
283 iova_insert_rbtree(&iovad->rbroot, new, prev);
284 __cached_rbnode_insert_update(iovad, new);
285
286 spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
287 return 0;
288
289iova32_full:
290 spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
291 return -ENOMEM;
292}
293
294static struct kmem_cache *iova_cache;
295static unsigned int iova_cache_users;
296static DEFINE_MUTEX(iova_cache_mutex);
297
298static struct iova *alloc_iova_mem(void)
299{
300 return kmem_cache_zalloc(iova_cache, GFP_ATOMIC | __GFP_NOWARN);
301}
302
303static void free_iova_mem(struct iova *iova)
304{
305 if (iova->pfn_lo != IOVA_ANCHOR)
306 kmem_cache_free(iova_cache, iova);
307}
308
309int iova_cache_get(void)
310{
311 mutex_lock(&iova_cache_mutex);
312 if (!iova_cache_users) {
313 int ret;
314
315 ret = cpuhp_setup_state_multi(CPUHP_IOMMU_IOVA_DEAD, "iommu/iova:dead", NULL,
316 iova_cpuhp_dead);
317 if (ret) {
318 mutex_unlock(&iova_cache_mutex);
319 pr_err("Couldn't register cpuhp handler\n");
320 return ret;
321 }
322
323 iova_cache = kmem_cache_create(
324 "iommu_iova", sizeof(struct iova), 0,
325 SLAB_HWCACHE_ALIGN, NULL);
326 if (!iova_cache) {
327 cpuhp_remove_multi_state(CPUHP_IOMMU_IOVA_DEAD);
328 mutex_unlock(&iova_cache_mutex);
329 pr_err("Couldn't create iova cache\n");
330 return -ENOMEM;
331 }
332 }
333
334 iova_cache_users++;
335 mutex_unlock(&iova_cache_mutex);
336
337 return 0;
338}
339EXPORT_SYMBOL_GPL(iova_cache_get);
340
341void iova_cache_put(void)
342{
343 mutex_lock(&iova_cache_mutex);
344 if (WARN_ON(!iova_cache_users)) {
345 mutex_unlock(&iova_cache_mutex);
346 return;
347 }
348 iova_cache_users--;
349 if (!iova_cache_users) {
350 cpuhp_remove_multi_state(CPUHP_IOMMU_IOVA_DEAD);
351 kmem_cache_destroy(iova_cache);
352 }
353 mutex_unlock(&iova_cache_mutex);
354}
355EXPORT_SYMBOL_GPL(iova_cache_put);
356
357
358
359
360
361
362
363
364
365
366
367
368struct iova *
369alloc_iova(struct iova_domain *iovad, unsigned long size,
370 unsigned long limit_pfn,
371 bool size_aligned)
372{
373 struct iova *new_iova;
374 int ret;
375
376 new_iova = alloc_iova_mem();
377 if (!new_iova)
378 return NULL;
379
380 ret = __alloc_and_insert_iova_range(iovad, size, limit_pfn + 1,
381 new_iova, size_aligned);
382
383 if (ret) {
384 free_iova_mem(new_iova);
385 return NULL;
386 }
387
388 return new_iova;
389}
390EXPORT_SYMBOL_GPL(alloc_iova);
391
392static struct iova *
393private_find_iova(struct iova_domain *iovad, unsigned long pfn)
394{
395 struct rb_node *node = iovad->rbroot.rb_node;
396
397 assert_spin_locked(&iovad->iova_rbtree_lock);
398
399 while (node) {
400 struct iova *iova = to_iova(node);
401
402 if (pfn < iova->pfn_lo)
403 node = node->rb_left;
404 else if (pfn > iova->pfn_hi)
405 node = node->rb_right;
406 else
407 return iova;
408 }
409
410 return NULL;
411}
412
413static void remove_iova(struct iova_domain *iovad, struct iova *iova)
414{
415 assert_spin_locked(&iovad->iova_rbtree_lock);
416 __cached_rbnode_delete_update(iovad, iova);
417 rb_erase(&iova->node, &iovad->rbroot);
418}
419
420
421
422
423
424
425
426
427struct iova *find_iova(struct iova_domain *iovad, unsigned long pfn)
428{
429 unsigned long flags;
430 struct iova *iova;
431
432
433 spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
434 iova = private_find_iova(iovad, pfn);
435 spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
436 return iova;
437}
438EXPORT_SYMBOL_GPL(find_iova);
439
440
441
442
443
444
445
446void
447__free_iova(struct iova_domain *iovad, struct iova *iova)
448{
449 unsigned long flags;
450
451 spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
452 remove_iova(iovad, iova);
453 spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
454 free_iova_mem(iova);
455}
456EXPORT_SYMBOL_GPL(__free_iova);
457
458
459
460
461
462
463
464
465void
466free_iova(struct iova_domain *iovad, unsigned long pfn)
467{
468 unsigned long flags;
469 struct iova *iova;
470
471 spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
472 iova = private_find_iova(iovad, pfn);
473 if (!iova) {
474 spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
475 return;
476 }
477 remove_iova(iovad, iova);
478 spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
479 free_iova_mem(iova);
480}
481EXPORT_SYMBOL_GPL(free_iova);
482
483
484
485
486
487
488
489
490
491
492
493unsigned long
494alloc_iova_fast(struct iova_domain *iovad, unsigned long size,
495 unsigned long limit_pfn, bool flush_rcache)
496{
497 unsigned long iova_pfn;
498 struct iova *new_iova;
499
500 iova_pfn = iova_rcache_get(iovad, size, limit_pfn + 1);
501 if (iova_pfn)
502 return iova_pfn;
503
504retry:
505 new_iova = alloc_iova(iovad, size, limit_pfn, true);
506 if (!new_iova) {
507 unsigned int cpu;
508
509 if (!flush_rcache)
510 return 0;
511
512
513 flush_rcache = false;
514 for_each_online_cpu(cpu)
515 free_cpu_cached_iovas(cpu, iovad);
516 free_global_cached_iovas(iovad);
517 goto retry;
518 }
519
520 return new_iova->pfn_lo;
521}
522EXPORT_SYMBOL_GPL(alloc_iova_fast);
523
524
525
526
527
528
529
530
531
532void
533free_iova_fast(struct iova_domain *iovad, unsigned long pfn, unsigned long size)
534{
535 if (iova_rcache_insert(iovad, pfn, size))
536 return;
537
538 free_iova(iovad, pfn);
539}
540EXPORT_SYMBOL_GPL(free_iova_fast);
541
542#define fq_ring_for_each(i, fq) \
543 for ((i) = (fq)->head; (i) != (fq)->tail; (i) = ((i) + 1) % IOVA_FQ_SIZE)
544
545static inline bool fq_full(struct iova_fq *fq)
546{
547 assert_spin_locked(&fq->lock);
548 return (((fq->tail + 1) % IOVA_FQ_SIZE) == fq->head);
549}
550
551static inline unsigned fq_ring_add(struct iova_fq *fq)
552{
553 unsigned idx = fq->tail;
554
555 assert_spin_locked(&fq->lock);
556
557 fq->tail = (idx + 1) % IOVA_FQ_SIZE;
558
559 return idx;
560}
561
562static void fq_ring_free(struct iova_domain *iovad, struct iova_fq *fq)
563{
564 u64 counter = atomic64_read(&iovad->fq_flush_finish_cnt);
565 unsigned idx;
566
567 assert_spin_locked(&fq->lock);
568
569 fq_ring_for_each(idx, fq) {
570
571 if (fq->entries[idx].counter >= counter)
572 break;
573
574 if (iovad->entry_dtor)
575 iovad->entry_dtor(fq->entries[idx].data);
576
577 free_iova_fast(iovad,
578 fq->entries[idx].iova_pfn,
579 fq->entries[idx].pages);
580
581 fq->head = (fq->head + 1) % IOVA_FQ_SIZE;
582 }
583}
584
585static void iova_domain_flush(struct iova_domain *iovad)
586{
587 atomic64_inc(&iovad->fq_flush_start_cnt);
588 iovad->flush_cb(iovad);
589 atomic64_inc(&iovad->fq_flush_finish_cnt);
590}
591
592static void fq_destroy_all_entries(struct iova_domain *iovad)
593{
594 int cpu;
595
596
597
598
599
600
601 if (!iovad->entry_dtor)
602 return;
603
604 for_each_possible_cpu(cpu) {
605 struct iova_fq *fq = per_cpu_ptr(iovad->fq, cpu);
606 int idx;
607
608 fq_ring_for_each(idx, fq)
609 iovad->entry_dtor(fq->entries[idx].data);
610 }
611}
612
613static void fq_flush_timeout(struct timer_list *t)
614{
615 struct iova_domain *iovad = from_timer(iovad, t, fq_timer);
616 int cpu;
617
618 atomic_set(&iovad->fq_timer_on, 0);
619 iova_domain_flush(iovad);
620
621 for_each_possible_cpu(cpu) {
622 unsigned long flags;
623 struct iova_fq *fq;
624
625 fq = per_cpu_ptr(iovad->fq, cpu);
626 spin_lock_irqsave(&fq->lock, flags);
627 fq_ring_free(iovad, fq);
628 spin_unlock_irqrestore(&fq->lock, flags);
629 }
630}
631
632void queue_iova(struct iova_domain *iovad,
633 unsigned long pfn, unsigned long pages,
634 unsigned long data)
635{
636 struct iova_fq *fq;
637 unsigned long flags;
638 unsigned idx;
639
640
641
642
643
644
645
646
647 smp_mb();
648
649 fq = raw_cpu_ptr(iovad->fq);
650 spin_lock_irqsave(&fq->lock, flags);
651
652
653
654
655
656
657 fq_ring_free(iovad, fq);
658
659 if (fq_full(fq)) {
660 iova_domain_flush(iovad);
661 fq_ring_free(iovad, fq);
662 }
663
664 idx = fq_ring_add(fq);
665
666 fq->entries[idx].iova_pfn = pfn;
667 fq->entries[idx].pages = pages;
668 fq->entries[idx].data = data;
669 fq->entries[idx].counter = atomic64_read(&iovad->fq_flush_start_cnt);
670
671 spin_unlock_irqrestore(&fq->lock, flags);
672
673
674 if (!atomic_read(&iovad->fq_timer_on) &&
675 !atomic_xchg(&iovad->fq_timer_on, 1))
676 mod_timer(&iovad->fq_timer,
677 jiffies + msecs_to_jiffies(IOVA_FQ_TIMEOUT));
678}
679
680
681
682
683
684
685void put_iova_domain(struct iova_domain *iovad)
686{
687 struct iova *iova, *tmp;
688
689 cpuhp_state_remove_instance_nocalls(CPUHP_IOMMU_IOVA_DEAD,
690 &iovad->cpuhp_dead);
691
692 free_iova_flush_queue(iovad);
693 free_iova_rcaches(iovad);
694 rbtree_postorder_for_each_entry_safe(iova, tmp, &iovad->rbroot, node)
695 free_iova_mem(iova);
696}
697EXPORT_SYMBOL_GPL(put_iova_domain);
698
699static int
700__is_range_overlap(struct rb_node *node,
701 unsigned long pfn_lo, unsigned long pfn_hi)
702{
703 struct iova *iova = to_iova(node);
704
705 if ((pfn_lo <= iova->pfn_hi) && (pfn_hi >= iova->pfn_lo))
706 return 1;
707 return 0;
708}
709
710static inline struct iova *
711alloc_and_init_iova(unsigned long pfn_lo, unsigned long pfn_hi)
712{
713 struct iova *iova;
714
715 iova = alloc_iova_mem();
716 if (iova) {
717 iova->pfn_lo = pfn_lo;
718 iova->pfn_hi = pfn_hi;
719 }
720
721 return iova;
722}
723
724static struct iova *
725__insert_new_range(struct iova_domain *iovad,
726 unsigned long pfn_lo, unsigned long pfn_hi)
727{
728 struct iova *iova;
729
730 iova = alloc_and_init_iova(pfn_lo, pfn_hi);
731 if (iova)
732 iova_insert_rbtree(&iovad->rbroot, iova, NULL);
733
734 return iova;
735}
736
737static void
738__adjust_overlap_range(struct iova *iova,
739 unsigned long *pfn_lo, unsigned long *pfn_hi)
740{
741 if (*pfn_lo < iova->pfn_lo)
742 iova->pfn_lo = *pfn_lo;
743 if (*pfn_hi > iova->pfn_hi)
744 *pfn_lo = iova->pfn_hi + 1;
745}
746
747
748
749
750
751
752
753
754
755struct iova *
756reserve_iova(struct iova_domain *iovad,
757 unsigned long pfn_lo, unsigned long pfn_hi)
758{
759 struct rb_node *node;
760 unsigned long flags;
761 struct iova *iova;
762 unsigned int overlap = 0;
763
764
765 if (WARN_ON((pfn_hi | pfn_lo) > (ULLONG_MAX >> iova_shift(iovad))))
766 return NULL;
767
768 spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
769 for (node = rb_first(&iovad->rbroot); node; node = rb_next(node)) {
770 if (__is_range_overlap(node, pfn_lo, pfn_hi)) {
771 iova = to_iova(node);
772 __adjust_overlap_range(iova, &pfn_lo, &pfn_hi);
773 if ((pfn_lo >= iova->pfn_lo) &&
774 (pfn_hi <= iova->pfn_hi))
775 goto finish;
776 overlap = 1;
777
778 } else if (overlap)
779 break;
780 }
781
782
783
784
785 iova = __insert_new_range(iovad, pfn_lo, pfn_hi);
786finish:
787
788 spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
789 return iova;
790}
791EXPORT_SYMBOL_GPL(reserve_iova);
792
793
794
795
796
797
798
799
800
801#define IOVA_MAG_SIZE 128
802
803struct iova_magazine {
804 unsigned long size;
805 unsigned long pfns[IOVA_MAG_SIZE];
806};
807
808struct iova_cpu_rcache {
809 spinlock_t lock;
810 struct iova_magazine *loaded;
811 struct iova_magazine *prev;
812};
813
814static struct iova_magazine *iova_magazine_alloc(gfp_t flags)
815{
816 return kzalloc(sizeof(struct iova_magazine), flags);
817}
818
819static void iova_magazine_free(struct iova_magazine *mag)
820{
821 kfree(mag);
822}
823
824static void
825iova_magazine_free_pfns(struct iova_magazine *mag, struct iova_domain *iovad)
826{
827 unsigned long flags;
828 int i;
829
830 if (!mag)
831 return;
832
833 spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
834
835 for (i = 0 ; i < mag->size; ++i) {
836 struct iova *iova = private_find_iova(iovad, mag->pfns[i]);
837
838 if (WARN_ON(!iova))
839 continue;
840
841 remove_iova(iovad, iova);
842 free_iova_mem(iova);
843 }
844
845 spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
846
847 mag->size = 0;
848}
849
850static bool iova_magazine_full(struct iova_magazine *mag)
851{
852 return (mag && mag->size == IOVA_MAG_SIZE);
853}
854
855static bool iova_magazine_empty(struct iova_magazine *mag)
856{
857 return (!mag || mag->size == 0);
858}
859
860static unsigned long iova_magazine_pop(struct iova_magazine *mag,
861 unsigned long limit_pfn)
862{
863 int i;
864 unsigned long pfn;
865
866 BUG_ON(iova_magazine_empty(mag));
867
868
869 for (i = mag->size - 1; mag->pfns[i] > limit_pfn; i--)
870 if (i == 0)
871 return 0;
872
873
874 pfn = mag->pfns[i];
875 mag->pfns[i] = mag->pfns[--mag->size];
876
877 return pfn;
878}
879
880static void iova_magazine_push(struct iova_magazine *mag, unsigned long pfn)
881{
882 BUG_ON(iova_magazine_full(mag));
883
884 mag->pfns[mag->size++] = pfn;
885}
886
887static void init_iova_rcaches(struct iova_domain *iovad)
888{
889 struct iova_cpu_rcache *cpu_rcache;
890 struct iova_rcache *rcache;
891 unsigned int cpu;
892 int i;
893
894 for (i = 0; i < IOVA_RANGE_CACHE_MAX_SIZE; ++i) {
895 rcache = &iovad->rcaches[i];
896 spin_lock_init(&rcache->lock);
897 rcache->depot_size = 0;
898 rcache->cpu_rcaches = __alloc_percpu(sizeof(*cpu_rcache), cache_line_size());
899 if (WARN_ON(!rcache->cpu_rcaches))
900 continue;
901 for_each_possible_cpu(cpu) {
902 cpu_rcache = per_cpu_ptr(rcache->cpu_rcaches, cpu);
903 spin_lock_init(&cpu_rcache->lock);
904 cpu_rcache->loaded = iova_magazine_alloc(GFP_KERNEL);
905 cpu_rcache->prev = iova_magazine_alloc(GFP_KERNEL);
906 }
907 }
908}
909
910
911
912
913
914
915
916static bool __iova_rcache_insert(struct iova_domain *iovad,
917 struct iova_rcache *rcache,
918 unsigned long iova_pfn)
919{
920 struct iova_magazine *mag_to_free = NULL;
921 struct iova_cpu_rcache *cpu_rcache;
922 bool can_insert = false;
923 unsigned long flags;
924
925 cpu_rcache = raw_cpu_ptr(rcache->cpu_rcaches);
926 spin_lock_irqsave(&cpu_rcache->lock, flags);
927
928 if (!iova_magazine_full(cpu_rcache->loaded)) {
929 can_insert = true;
930 } else if (!iova_magazine_full(cpu_rcache->prev)) {
931 swap(cpu_rcache->prev, cpu_rcache->loaded);
932 can_insert = true;
933 } else {
934 struct iova_magazine *new_mag = iova_magazine_alloc(GFP_ATOMIC);
935
936 if (new_mag) {
937 spin_lock(&rcache->lock);
938 if (rcache->depot_size < MAX_GLOBAL_MAGS) {
939 rcache->depot[rcache->depot_size++] =
940 cpu_rcache->loaded;
941 } else {
942 mag_to_free = cpu_rcache->loaded;
943 }
944 spin_unlock(&rcache->lock);
945
946 cpu_rcache->loaded = new_mag;
947 can_insert = true;
948 }
949 }
950
951 if (can_insert)
952 iova_magazine_push(cpu_rcache->loaded, iova_pfn);
953
954 spin_unlock_irqrestore(&cpu_rcache->lock, flags);
955
956 if (mag_to_free) {
957 iova_magazine_free_pfns(mag_to_free, iovad);
958 iova_magazine_free(mag_to_free);
959 }
960
961 return can_insert;
962}
963
964static bool iova_rcache_insert(struct iova_domain *iovad, unsigned long pfn,
965 unsigned long size)
966{
967 unsigned int log_size = order_base_2(size);
968
969 if (log_size >= IOVA_RANGE_CACHE_MAX_SIZE)
970 return false;
971
972 return __iova_rcache_insert(iovad, &iovad->rcaches[log_size], pfn);
973}
974
975
976
977
978
979
980static unsigned long __iova_rcache_get(struct iova_rcache *rcache,
981 unsigned long limit_pfn)
982{
983 struct iova_cpu_rcache *cpu_rcache;
984 unsigned long iova_pfn = 0;
985 bool has_pfn = false;
986 unsigned long flags;
987
988 cpu_rcache = raw_cpu_ptr(rcache->cpu_rcaches);
989 spin_lock_irqsave(&cpu_rcache->lock, flags);
990
991 if (!iova_magazine_empty(cpu_rcache->loaded)) {
992 has_pfn = true;
993 } else if (!iova_magazine_empty(cpu_rcache->prev)) {
994 swap(cpu_rcache->prev, cpu_rcache->loaded);
995 has_pfn = true;
996 } else {
997 spin_lock(&rcache->lock);
998 if (rcache->depot_size > 0) {
999 iova_magazine_free(cpu_rcache->loaded);
1000 cpu_rcache->loaded = rcache->depot[--rcache->depot_size];
1001 has_pfn = true;
1002 }
1003 spin_unlock(&rcache->lock);
1004 }
1005
1006 if (has_pfn)
1007 iova_pfn = iova_magazine_pop(cpu_rcache->loaded, limit_pfn);
1008
1009 spin_unlock_irqrestore(&cpu_rcache->lock, flags);
1010
1011 return iova_pfn;
1012}
1013
1014
1015
1016
1017
1018
1019static unsigned long iova_rcache_get(struct iova_domain *iovad,
1020 unsigned long size,
1021 unsigned long limit_pfn)
1022{
1023 unsigned int log_size = order_base_2(size);
1024
1025 if (log_size >= IOVA_RANGE_CACHE_MAX_SIZE)
1026 return 0;
1027
1028 return __iova_rcache_get(&iovad->rcaches[log_size], limit_pfn - size);
1029}
1030
1031
1032
1033
1034static void free_iova_rcaches(struct iova_domain *iovad)
1035{
1036 struct iova_rcache *rcache;
1037 struct iova_cpu_rcache *cpu_rcache;
1038 unsigned int cpu;
1039 int i, j;
1040
1041 for (i = 0; i < IOVA_RANGE_CACHE_MAX_SIZE; ++i) {
1042 rcache = &iovad->rcaches[i];
1043 for_each_possible_cpu(cpu) {
1044 cpu_rcache = per_cpu_ptr(rcache->cpu_rcaches, cpu);
1045 iova_magazine_free(cpu_rcache->loaded);
1046 iova_magazine_free(cpu_rcache->prev);
1047 }
1048 free_percpu(rcache->cpu_rcaches);
1049 for (j = 0; j < rcache->depot_size; ++j)
1050 iova_magazine_free(rcache->depot[j]);
1051 }
1052}
1053
1054
1055
1056
1057static void free_cpu_cached_iovas(unsigned int cpu, struct iova_domain *iovad)
1058{
1059 struct iova_cpu_rcache *cpu_rcache;
1060 struct iova_rcache *rcache;
1061 unsigned long flags;
1062 int i;
1063
1064 for (i = 0; i < IOVA_RANGE_CACHE_MAX_SIZE; ++i) {
1065 rcache = &iovad->rcaches[i];
1066 cpu_rcache = per_cpu_ptr(rcache->cpu_rcaches, cpu);
1067 spin_lock_irqsave(&cpu_rcache->lock, flags);
1068 iova_magazine_free_pfns(cpu_rcache->loaded, iovad);
1069 iova_magazine_free_pfns(cpu_rcache->prev, iovad);
1070 spin_unlock_irqrestore(&cpu_rcache->lock, flags);
1071 }
1072}
1073
1074
1075
1076
1077static void free_global_cached_iovas(struct iova_domain *iovad)
1078{
1079 struct iova_rcache *rcache;
1080 unsigned long flags;
1081 int i, j;
1082
1083 for (i = 0; i < IOVA_RANGE_CACHE_MAX_SIZE; ++i) {
1084 rcache = &iovad->rcaches[i];
1085 spin_lock_irqsave(&rcache->lock, flags);
1086 for (j = 0; j < rcache->depot_size; ++j) {
1087 iova_magazine_free_pfns(rcache->depot[j], iovad);
1088 iova_magazine_free(rcache->depot[j]);
1089 }
1090 rcache->depot_size = 0;
1091 spin_unlock_irqrestore(&rcache->lock, flags);
1092 }
1093}
1094MODULE_AUTHOR("Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>");
1095MODULE_LICENSE("GPL");
1096