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Linux 4.19.133
[linux/fpc-iii.git] / drivers / vfio / vfio_iommu_spapr_tce.c
blobec53310f1613601c2e9ed9a5490c044dca6d782e
1 /*
2 * VFIO: IOMMU DMA mapping support for TCE on POWER
3 *
4 * Copyright (C) 2013 IBM Corp. All rights reserved.
5 * Author: Alexey Kardashevskiy <aik@ozlabs.ru>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 *
11 * Derived from original vfio_iommu_type1.c:
12 * Copyright (C) 2012 Red Hat, Inc. All rights reserved.
13 * Author: Alex Williamson <alex.williamson@redhat.com>
14 */
15
16 #include <linux/module.h>
17 #include <linux/pci.h>
18 #include <linux/slab.h>
19 #include <linux/uaccess.h>
20 #include <linux/err.h>
21 #include <linux/vfio.h>
22 #include <linux/vmalloc.h>
23 #include <linux/sched/mm.h>
24 #include <linux/sched/signal.h>
25
26 #include <asm/iommu.h>
27 #include <asm/tce.h>
28 #include <asm/mmu_context.h>
29
30 #define DRIVER_VERSION "0.1"
31 #define DRIVER_AUTHOR "aik@ozlabs.ru"
32 #define DRIVER_DESC "VFIO IOMMU SPAPR TCE"
33
34 static void tce_iommu_detach_group(void *iommu_data,
35 struct iommu_group *iommu_group);
36
37 static long try_increment_locked_vm(struct mm_struct *mm, long npages)
38 {
39 long ret = 0, locked, lock_limit;
40
41 if (WARN_ON_ONCE(!mm))
42 return -EPERM;
43
44 if (!npages)
45 return 0;
46
47 down_write(&mm->mmap_sem);
48 locked = mm->locked_vm + npages;
49 lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
50 if (locked > lock_limit && !capable(CAP_IPC_LOCK))
51 ret = -ENOMEM;
52 else
53 mm->locked_vm += npages;
54
55 pr_debug("[%d] RLIMIT_MEMLOCK +%ld %ld/%ld%s\n", current->pid,
56 npages << PAGE_SHIFT,
57 mm->locked_vm << PAGE_SHIFT,
58 rlimit(RLIMIT_MEMLOCK),
59 ret ? " - exceeded" : "");
60
61 up_write(&mm->mmap_sem);
62
63 return ret;
64 }
65
66 static void decrement_locked_vm(struct mm_struct *mm, long npages)
67 {
68 if (!mm || !npages)
69 return;
70
71 down_write(&mm->mmap_sem);
72 if (WARN_ON_ONCE(npages > mm->locked_vm))
73 npages = mm->locked_vm;
74 mm->locked_vm -= npages;
75 pr_debug("[%d] RLIMIT_MEMLOCK -%ld %ld/%ld\n", current->pid,
76 npages << PAGE_SHIFT,
77 mm->locked_vm << PAGE_SHIFT,
78 rlimit(RLIMIT_MEMLOCK));
79 up_write(&mm->mmap_sem);
80 }
81
82 /*
83 * VFIO IOMMU fd for SPAPR_TCE IOMMU implementation
84 *
85 * This code handles mapping and unmapping of user data buffers
86 * into DMA'ble space using the IOMMU
87 */
88
89 struct tce_iommu_group {
90 struct list_head next;
91 struct iommu_group *grp;
92 };
93
94 /*
95 * A container needs to remember which preregistered region it has
96 * referenced to do proper cleanup at the userspace process exit.
97 */
98 struct tce_iommu_prereg {
99 struct list_head next;
100 struct mm_iommu_table_group_mem_t *mem;
101 };
102
103 /*
104 * The container descriptor supports only a single group per container.
105 * Required by the API as the container is not supplied with the IOMMU group
106 * at the moment of initialization.
107 */
108 struct tce_container {
109 struct mutex lock;
110 bool enabled;
111 bool v2;
112 bool def_window_pending;
113 unsigned long locked_pages;
114 struct mm_struct *mm;
115 struct iommu_table *tables[IOMMU_TABLE_GROUP_MAX_TABLES];
116 struct list_head group_list;
117 struct list_head prereg_list;
118 };
119
120 static long tce_iommu_mm_set(struct tce_container *container)
121 {
122 if (container->mm) {
123 if (container->mm == current->mm)
124 return 0;
125 return -EPERM;
126 }
127 BUG_ON(!current->mm);
128 container->mm = current->mm;
129 atomic_inc(&container->mm->mm_count);
130
131 return 0;
132 }
133
134 static long tce_iommu_prereg_free(struct tce_container *container,
135 struct tce_iommu_prereg *tcemem)
136 {
137 long ret;
138
139 ret = mm_iommu_put(container->mm, tcemem->mem);
140 if (ret)
141 return ret;
142
143 list_del(&tcemem->next);
144 kfree(tcemem);
145
146 return 0;
147 }
148
149 static long tce_iommu_unregister_pages(struct tce_container *container,
150 __u64 vaddr, __u64 size)
151 {
152 struct mm_iommu_table_group_mem_t *mem;
153 struct tce_iommu_prereg *tcemem;
154 bool found = false;
155
156 if ((vaddr & ~PAGE_MASK) || (size & ~PAGE_MASK))
157 return -EINVAL;
158
159 mem = mm_iommu_find(container->mm, vaddr, size >> PAGE_SHIFT);
160 if (!mem)
161 return -ENOENT;
162
163 list_for_each_entry(tcemem, &container->prereg_list, next) {
164 if (tcemem->mem == mem) {
165 found = true;
166 break;
167 }
168 }
169
170 if (!found)
171 return -ENOENT;
172
173 return tce_iommu_prereg_free(container, tcemem);
174 }
175
176 static long tce_iommu_register_pages(struct tce_container *container,
177 __u64 vaddr, __u64 size)
178 {
179 long ret = 0;
180 struct mm_iommu_table_group_mem_t *mem = NULL;
181 struct tce_iommu_prereg *tcemem;
182 unsigned long entries = size >> PAGE_SHIFT;
183
184 if ((vaddr & ~PAGE_MASK) || (size & ~PAGE_MASK) ||
185 ((vaddr + size) < vaddr))
186 return -EINVAL;
187
188 mem = mm_iommu_find(container->mm, vaddr, entries);
189 if (mem) {
190 list_for_each_entry(tcemem, &container->prereg_list, next) {
191 if (tcemem->mem == mem)
192 return -EBUSY;
193 }
194 }
195
196 ret = mm_iommu_get(container->mm, vaddr, entries, &mem);
197 if (ret)
198 return ret;
199
200 tcemem = kzalloc(sizeof(*tcemem), GFP_KERNEL);
201 if (!tcemem) {
202 mm_iommu_put(container->mm, mem);
203 return -ENOMEM;
204 }
205
206 tcemem->mem = mem;
207 list_add(&tcemem->next, &container->prereg_list);
208
209 container->enabled = true;
210
211 return 0;
212 }
213
214 static bool tce_page_is_contained(struct page *page, unsigned page_shift)
215 {
216 /*
217 * Check that the TCE table granularity is not bigger than the size of
218 * a page we just found. Otherwise the hardware can get access to
219 * a bigger memory chunk that it should.
220 */
221 return (PAGE_SHIFT + compound_order(compound_head(page))) >= page_shift;
222 }
223
224 static inline bool tce_groups_attached(struct tce_container *container)
225 {
226 return !list_empty(&container->group_list);
227 }
228
229 static long tce_iommu_find_table(struct tce_container *container,
230 phys_addr_t ioba, struct iommu_table **ptbl)
231 {
232 long i;
233
234 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) {
235 struct iommu_table *tbl = container->tables[i];
236
237 if (tbl) {
238 unsigned long entry = ioba >> tbl->it_page_shift;
239 unsigned long start = tbl->it_offset;
240 unsigned long end = start + tbl->it_size;
241
242 if ((start <= entry) && (entry < end)) {
243 *ptbl = tbl;
244 return i;
245 }
246 }
247 }
248
249 return -1;
250 }
251
252 static int tce_iommu_find_free_table(struct tce_container *container)
253 {
254 int i;
255
256 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) {
257 if (!container->tables[i])
258 return i;
259 }
260
261 return -ENOSPC;
262 }
263
264 static int tce_iommu_enable(struct tce_container *container)
265 {
266 int ret = 0;
267 unsigned long locked;
268 struct iommu_table_group *table_group;
269 struct tce_iommu_group *tcegrp;
270
271 if (container->enabled)
272 return -EBUSY;
273
274 /*
275 * When userspace pages are mapped into the IOMMU, they are effectively
276 * locked memory, so, theoretically, we need to update the accounting
277 * of locked pages on each map and unmap. For powerpc, the map unmap
278 * paths can be very hot, though, and the accounting would kill
279 * performance, especially since it would be difficult to impossible
280 * to handle the accounting in real mode only.
281 *
282 * To address that, rather than precisely accounting every page, we
283 * instead account for a worst case on locked memory when the iommu is
284 * enabled and disabled. The worst case upper bound on locked memory
285 * is the size of the whole iommu window, which is usually relatively
286 * small (compared to total memory sizes) on POWER hardware.
287 *
288 * Also we don't have a nice way to fail on H_PUT_TCE due to ulimits,
289 * that would effectively kill the guest at random points, much better
290 * enforcing the limit based on the max that the guest can map.
291 *
292 * Unfortunately at the moment it counts whole tables, no matter how
293 * much memory the guest has. I.e. for 4GB guest and 4 IOMMU groups
294 * each with 2GB DMA window, 8GB will be counted here. The reason for
295 * this is that we cannot tell here the amount of RAM used by the guest
296 * as this information is only available from KVM and VFIO is
297 * KVM agnostic.
298 *
299 * So we do not allow enabling a container without a group attached
300 * as there is no way to know how much we should increment
301 * the locked_vm counter.
302 */
303 if (!tce_groups_attached(container))
304 return -ENODEV;
305
306 tcegrp = list_first_entry(&container->group_list,
307 struct tce_iommu_group, next);
308 table_group = iommu_group_get_iommudata(tcegrp->grp);
309 if (!table_group)
310 return -ENODEV;
311
312 if (!table_group->tce32_size)
313 return -EPERM;
314
315 ret = tce_iommu_mm_set(container);
316 if (ret)
317 return ret;
318
319 locked = table_group->tce32_size >> PAGE_SHIFT;
320 ret = try_increment_locked_vm(container->mm, locked);
321 if (ret)
322 return ret;
323
324 container->locked_pages = locked;
325
326 container->enabled = true;
327
328 return ret;
329 }
330
331 static void tce_iommu_disable(struct tce_container *container)
332 {
333 if (!container->enabled)
334 return;
335
336 container->enabled = false;
337
338 BUG_ON(!container->mm);
339 decrement_locked_vm(container->mm, container->locked_pages);
340 }
341
342 static void *tce_iommu_open(unsigned long arg)
343 {
344 struct tce_container *container;
345
346 if ((arg != VFIO_SPAPR_TCE_IOMMU) && (arg != VFIO_SPAPR_TCE_v2_IOMMU)) {
347 pr_err("tce_vfio: Wrong IOMMU type\n");
348 return ERR_PTR(-EINVAL);
349 }
350
351 container = kzalloc(sizeof(*container), GFP_KERNEL);
352 if (!container)
353 return ERR_PTR(-ENOMEM);
354
355 mutex_init(&container->lock);
356 INIT_LIST_HEAD_RCU(&container->group_list);
357 INIT_LIST_HEAD_RCU(&container->prereg_list);
358
359 container->v2 = arg == VFIO_SPAPR_TCE_v2_IOMMU;
360
361 return container;
362 }
363
364 static int tce_iommu_clear(struct tce_container *container,
365 struct iommu_table *tbl,
366 unsigned long entry, unsigned long pages);
367 static void tce_iommu_free_table(struct tce_container *container,
368 struct iommu_table *tbl);
369
370 static void tce_iommu_release(void *iommu_data)
371 {
372 struct tce_container *container = iommu_data;
373 struct tce_iommu_group *tcegrp;
374 struct tce_iommu_prereg *tcemem, *tmtmp;
375 long i;
376
377 while (tce_groups_attached(container)) {
378 tcegrp = list_first_entry(&container->group_list,
379 struct tce_iommu_group, next);
380 tce_iommu_detach_group(iommu_data, tcegrp->grp);
381 }
382
383 /*
384 * If VFIO created a table, it was not disposed
385 * by tce_iommu_detach_group() so do it now.
386 */
387 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) {
388 struct iommu_table *tbl = container->tables[i];
389
390 if (!tbl)
391 continue;
392
393 tce_iommu_clear(container, tbl, tbl->it_offset, tbl->it_size);
394 tce_iommu_free_table(container, tbl);
395 }
396
397 list_for_each_entry_safe(tcemem, tmtmp, &container->prereg_list, next)
398 WARN_ON(tce_iommu_prereg_free(container, tcemem));
399
400 tce_iommu_disable(container);
401 if (container->mm)
402 mmdrop(container->mm);
403 mutex_destroy(&container->lock);
404
405 kfree(container);
406 }
407
408 static void tce_iommu_unuse_page(struct tce_container *container,
409 unsigned long hpa)
410 {
411 struct page *page;
412
413 page = pfn_to_page(hpa >> PAGE_SHIFT);
414 put_page(page);
415 }
416
417 static int tce_iommu_prereg_ua_to_hpa(struct tce_container *container,
418 unsigned long tce, unsigned long shift,
419 unsigned long *phpa, struct mm_iommu_table_group_mem_t **pmem)
420 {
421 long ret = 0;
422 struct mm_iommu_table_group_mem_t *mem;
423
424 mem = mm_iommu_lookup(container->mm, tce, 1ULL << shift);
425 if (!mem)
426 return -EINVAL;
427
428 ret = mm_iommu_ua_to_hpa(mem, tce, shift, phpa);
429 if (ret)
430 return -EINVAL;
431
432 *pmem = mem;
433
434 return 0;
435 }
436
437 static void tce_iommu_unuse_page_v2(struct tce_container *container,
438 struct iommu_table *tbl, unsigned long entry)
439 {
440 struct mm_iommu_table_group_mem_t *mem = NULL;
441 int ret;
442 unsigned long hpa = 0;
443 __be64 *pua = IOMMU_TABLE_USERSPACE_ENTRY(tbl, entry);
444
445 if (!pua)
446 return;
447
448 ret = tce_iommu_prereg_ua_to_hpa(container, be64_to_cpu(*pua),
449 tbl->it_page_shift, &hpa, &mem);
450 if (ret)
451 pr_debug("%s: tce %llx at #%lx was not cached, ret=%d\n",
452 __func__, be64_to_cpu(*pua), entry, ret);
453 if (mem)
454 mm_iommu_mapped_dec(mem);
455
456 *pua = cpu_to_be64(0);
457 }
458
459 static int tce_iommu_clear(struct tce_container *container,
460 struct iommu_table *tbl,
461 unsigned long entry, unsigned long pages)
462 {
463 unsigned long oldhpa;
464 long ret;
465 enum dma_data_direction direction;
466
467 for ( ; pages; --pages, ++entry) {
468 cond_resched();
469
470 direction = DMA_NONE;
471 oldhpa = 0;
472 ret = iommu_tce_xchg(tbl, entry, &oldhpa, &direction);
473 if (ret)
474 continue;
475
476 if (direction == DMA_NONE)
477 continue;
478
479 if (container->v2) {
480 tce_iommu_unuse_page_v2(container, tbl, entry);
481 continue;
482 }
483
484 tce_iommu_unuse_page(container, oldhpa);
485 }
486
487 return 0;
488 }
489
490 static int tce_iommu_use_page(unsigned long tce, unsigned long *hpa)
491 {
492 struct page *page = NULL;
493 enum dma_data_direction direction = iommu_tce_direction(tce);
494
495 if (get_user_pages_fast(tce & PAGE_MASK, 1,
496 direction != DMA_TO_DEVICE, &page) != 1)
497 return -EFAULT;
498
499 *hpa = __pa((unsigned long) page_address(page));
500
501 return 0;
502 }
503
504 static long tce_iommu_build(struct tce_container *container,
505 struct iommu_table *tbl,
506 unsigned long entry, unsigned long tce, unsigned long pages,
507 enum dma_data_direction direction)
508 {
509 long i, ret = 0;
510 struct page *page;
511 unsigned long hpa;
512 enum dma_data_direction dirtmp;
513
514 for (i = 0; i < pages; ++i) {
515 unsigned long offset = tce & IOMMU_PAGE_MASK(tbl) & ~PAGE_MASK;
516
517 ret = tce_iommu_use_page(tce, &hpa);
518 if (ret)
519 break;
520
521 page = pfn_to_page(hpa >> PAGE_SHIFT);
522 if (!tce_page_is_contained(page, tbl->it_page_shift)) {
523 ret = -EPERM;
524 break;
525 }
526
527 hpa |= offset;
528 dirtmp = direction;
529 ret = iommu_tce_xchg(tbl, entry + i, &hpa, &dirtmp);
530 if (ret) {
531 tce_iommu_unuse_page(container, hpa);
532 pr_err("iommu_tce: %s failed ioba=%lx, tce=%lx, ret=%ld\n",
533 __func__, entry << tbl->it_page_shift,
534 tce, ret);
535 break;
536 }
537
538 if (dirtmp != DMA_NONE)
539 tce_iommu_unuse_page(container, hpa);
540
541 tce += IOMMU_PAGE_SIZE(tbl);
542 }
543
544 if (ret)
545 tce_iommu_clear(container, tbl, entry, i);
546
547 return ret;
548 }
549
550 static long tce_iommu_build_v2(struct tce_container *container,
551 struct iommu_table *tbl,
552 unsigned long entry, unsigned long tce, unsigned long pages,
553 enum dma_data_direction direction)
554 {
555 long i, ret = 0;
556 struct page *page;
557 unsigned long hpa;
558 enum dma_data_direction dirtmp;
559
560 for (i = 0; i < pages; ++i) {
561 struct mm_iommu_table_group_mem_t *mem = NULL;
562 __be64 *pua = IOMMU_TABLE_USERSPACE_ENTRY(tbl, entry + i);
563
564 ret = tce_iommu_prereg_ua_to_hpa(container,
565 tce, tbl->it_page_shift, &hpa, &mem);
566 if (ret)
567 break;
568
569 page = pfn_to_page(hpa >> PAGE_SHIFT);
570 if (!tce_page_is_contained(page, tbl->it_page_shift)) {
571 ret = -EPERM;
572 break;
573 }
574
575 /* Preserve offset within IOMMU page */
576 hpa |= tce & IOMMU_PAGE_MASK(tbl) & ~PAGE_MASK;
577 dirtmp = direction;
578
579 /* The registered region is being unregistered */
580 if (mm_iommu_mapped_inc(mem))
581 break;
582
583 ret = iommu_tce_xchg(tbl, entry + i, &hpa, &dirtmp);
584 if (ret) {
585 /* dirtmp cannot be DMA_NONE here */
586 tce_iommu_unuse_page_v2(container, tbl, entry + i);
587 pr_err("iommu_tce: %s failed ioba=%lx, tce=%lx, ret=%ld\n",
588 __func__, entry << tbl->it_page_shift,
589 tce, ret);
590 break;
591 }
592
593 if (dirtmp != DMA_NONE)
594 tce_iommu_unuse_page_v2(container, tbl, entry + i);
595
596 *pua = cpu_to_be64(tce);
597
598 tce += IOMMU_PAGE_SIZE(tbl);
599 }
600
601 if (ret)
602 tce_iommu_clear(container, tbl, entry, i);
603
604 return ret;
605 }
606
607 static long tce_iommu_create_table(struct tce_container *container,
608 struct iommu_table_group *table_group,
609 int num,
610 __u32 page_shift,
611 __u64 window_size,
612 __u32 levels,
613 struct iommu_table **ptbl)
614 {
615 long ret, table_size;
616
617 table_size = table_group->ops->get_table_size(page_shift, window_size,
618 levels);
619 if (!table_size)
620 return -EINVAL;
621
622 ret = try_increment_locked_vm(container->mm, table_size >> PAGE_SHIFT);
623 if (ret)
624 return ret;
625
626 ret = table_group->ops->create_table(table_group, num,
627 page_shift, window_size, levels, ptbl);
628
629 WARN_ON(!ret && !(*ptbl)->it_ops->free);
630 WARN_ON(!ret && ((*ptbl)->it_allocated_size > table_size));
631
632 return ret;
633 }
634
635 static void tce_iommu_free_table(struct tce_container *container,
636 struct iommu_table *tbl)
637 {
638 unsigned long pages = tbl->it_allocated_size >> PAGE_SHIFT;
639
640 iommu_tce_table_put(tbl);
641 decrement_locked_vm(container->mm, pages);
642 }
643
644 static long tce_iommu_create_window(struct tce_container *container,
645 __u32 page_shift, __u64 window_size, __u32 levels,
646 __u64 *start_addr)
647 {
648 struct tce_iommu_group *tcegrp;
649 struct iommu_table_group *table_group;
650 struct iommu_table *tbl = NULL;
651 long ret, num;
652
653 num = tce_iommu_find_free_table(container);
654 if (num < 0)
655 return num;
656
657 /* Get the first group for ops::create_table */
658 tcegrp = list_first_entry(&container->group_list,
659 struct tce_iommu_group, next);
660 table_group = iommu_group_get_iommudata(tcegrp->grp);
661 if (!table_group)
662 return -EFAULT;
663
664 if (!(table_group->pgsizes & (1ULL << page_shift)))
665 return -EINVAL;
666
667 if (!table_group->ops->set_window || !table_group->ops->unset_window ||
668 !table_group->ops->get_table_size ||
669 !table_group->ops->create_table)
670 return -EPERM;
671
672 /* Create TCE table */
673 ret = tce_iommu_create_table(container, table_group, num,
674 page_shift, window_size, levels, &tbl);
675 if (ret)
676 return ret;
677
678 BUG_ON(!tbl->it_ops->free);
679
680 /*
681 * Program the table to every group.
682 * Groups have been tested for compatibility at the attach time.
683 */
684 list_for_each_entry(tcegrp, &container->group_list, next) {
685 table_group = iommu_group_get_iommudata(tcegrp->grp);
686
687 ret = table_group->ops->set_window(table_group, num, tbl);
688 if (ret)
689 goto unset_exit;
690 }
691
692 container->tables[num] = tbl;
693
694 /* Return start address assigned by platform in create_table() */
695 *start_addr = tbl->it_offset << tbl->it_page_shift;
696
697 return 0;
698
699 unset_exit:
700 list_for_each_entry(tcegrp, &container->group_list, next) {
701 table_group = iommu_group_get_iommudata(tcegrp->grp);
702 table_group->ops->unset_window(table_group, num);
703 }
704 tce_iommu_free_table(container, tbl);
705
706 return ret;
707 }
708
709 static long tce_iommu_remove_window(struct tce_container *container,
710 __u64 start_addr)
711 {
712 struct iommu_table_group *table_group = NULL;
713 struct iommu_table *tbl;
714 struct tce_iommu_group *tcegrp;
715 int num;
716
717 num = tce_iommu_find_table(container, start_addr, &tbl);
718 if (num < 0)
719 return -EINVAL;
720
721 BUG_ON(!tbl->it_size);
722
723 /* Detach groups from IOMMUs */
724 list_for_each_entry(tcegrp, &container->group_list, next) {
725 table_group = iommu_group_get_iommudata(tcegrp->grp);
726
727 /*
728 * SPAPR TCE IOMMU exposes the default DMA window to
729 * the guest via dma32_window_start/size of
730 * VFIO_IOMMU_SPAPR_TCE_GET_INFO. Some platforms allow
731 * the userspace to remove this window, some do not so
732 * here we check for the platform capability.
733 */
734 if (!table_group->ops || !table_group->ops->unset_window)
735 return -EPERM;
736
737 table_group->ops->unset_window(table_group, num);
738 }
739
740 /* Free table */
741 tce_iommu_clear(container, tbl, tbl->it_offset, tbl->it_size);
742 tce_iommu_free_table(container, tbl);
743 container->tables[num] = NULL;
744
745 return 0;
746 }
747
748 static long tce_iommu_create_default_window(struct tce_container *container)
749 {
750 long ret;
751 __u64 start_addr = 0;
752 struct tce_iommu_group *tcegrp;
753 struct iommu_table_group *table_group;
754
755 if (!container->def_window_pending)
756 return 0;
757
758 if (!tce_groups_attached(container))
759 return -ENODEV;
760
761 tcegrp = list_first_entry(&container->group_list,
762 struct tce_iommu_group, next);
763 table_group = iommu_group_get_iommudata(tcegrp->grp);
764 if (!table_group)
765 return -ENODEV;
766
767 ret = tce_iommu_create_window(container, IOMMU_PAGE_SHIFT_4K,
768 table_group->tce32_size, 1, &start_addr);
769 WARN_ON_ONCE(!ret && start_addr);
770
771 if (!ret)
772 container->def_window_pending = false;
773
774 return ret;
775 }
776
777 static long tce_iommu_ioctl(void *iommu_data,
778 unsigned int cmd, unsigned long arg)
779 {
780 struct tce_container *container = iommu_data;
781 unsigned long minsz, ddwsz;
782 long ret;
783
784 switch (cmd) {
785 case VFIO_CHECK_EXTENSION:
786 switch (arg) {
787 case VFIO_SPAPR_TCE_IOMMU:
788 case VFIO_SPAPR_TCE_v2_IOMMU:
789 ret = 1;
790 break;
791 default:
792 ret = vfio_spapr_iommu_eeh_ioctl(NULL, cmd, arg);
793 break;
794 }
795
796 return (ret < 0) ? 0 : ret;
797 }
798
799 /*
800 * Sanity check to prevent one userspace from manipulating
801 * another userspace mm.
802 */
803 BUG_ON(!container);
804 if (container->mm && container->mm != current->mm)
805 return -EPERM;
806
807 switch (cmd) {
808 case VFIO_IOMMU_SPAPR_TCE_GET_INFO: {
809 struct vfio_iommu_spapr_tce_info info;
810 struct tce_iommu_group *tcegrp;
811 struct iommu_table_group *table_group;
812
813 if (!tce_groups_attached(container))
814 return -ENXIO;
815
816 tcegrp = list_first_entry(&container->group_list,
817 struct tce_iommu_group, next);
818 table_group = iommu_group_get_iommudata(tcegrp->grp);
819
820 if (!table_group)
821 return -ENXIO;
822
823 minsz = offsetofend(struct vfio_iommu_spapr_tce_info,
824 dma32_window_size);
825
826 if (copy_from_user(&info, (void __user *)arg, minsz))
827 return -EFAULT;
828
829 if (info.argsz < minsz)
830 return -EINVAL;
831
832 info.dma32_window_start = table_group->tce32_start;
833 info.dma32_window_size = table_group->tce32_size;
834 info.flags = 0;
835 memset(&info.ddw, 0, sizeof(info.ddw));
836
837 if (table_group->max_dynamic_windows_supported &&
838 container->v2) {
839 info.flags |= VFIO_IOMMU_SPAPR_INFO_DDW;
840 info.ddw.pgsizes = table_group->pgsizes;
841 info.ddw.max_dynamic_windows_supported =
842 table_group->max_dynamic_windows_supported;
843 info.ddw.levels = table_group->max_levels;
844 }
845
846 ddwsz = offsetofend(struct vfio_iommu_spapr_tce_info, ddw);
847
848 if (info.argsz >= ddwsz)
849 minsz = ddwsz;
850
851 if (copy_to_user((void __user *)arg, &info, minsz))
852 return -EFAULT;
853
854 return 0;
855 }
856 case VFIO_IOMMU_MAP_DMA: {
857 struct vfio_iommu_type1_dma_map param;
858 struct iommu_table *tbl = NULL;
859 long num;
860 enum dma_data_direction direction;
861
862 if (!container->enabled)
863 return -EPERM;
864
865 minsz = offsetofend(struct vfio_iommu_type1_dma_map, size);
866
867 if (copy_from_user(&param, (void __user *)arg, minsz))
868 return -EFAULT;
869
870 if (param.argsz < minsz)
871 return -EINVAL;
872
873 if (param.flags & ~(VFIO_DMA_MAP_FLAG_READ |
874 VFIO_DMA_MAP_FLAG_WRITE))
875 return -EINVAL;
876
877 ret = tce_iommu_create_default_window(container);
878 if (ret)
879 return ret;
880
881 num = tce_iommu_find_table(container, param.iova, &tbl);
882 if (num < 0)
883 return -ENXIO;
884
885 if ((param.size & ~IOMMU_PAGE_MASK(tbl)) ||
886 (param.vaddr & ~IOMMU_PAGE_MASK(tbl)))
887 return -EINVAL;
888
889 /* iova is checked by the IOMMU API */
890 if (param.flags & VFIO_DMA_MAP_FLAG_READ) {
891 if (param.flags & VFIO_DMA_MAP_FLAG_WRITE)
892 direction = DMA_BIDIRECTIONAL;
893 else
894 direction = DMA_TO_DEVICE;
895 } else {
896 if (param.flags & VFIO_DMA_MAP_FLAG_WRITE)
897 direction = DMA_FROM_DEVICE;
898 else
899 return -EINVAL;
900 }
901
902 ret = iommu_tce_put_param_check(tbl, param.iova, param.vaddr);
903 if (ret)
904 return ret;
905
906 if (container->v2)
907 ret = tce_iommu_build_v2(container, tbl,
908 param.iova >> tbl->it_page_shift,
909 param.vaddr,
910 param.size >> tbl->it_page_shift,
911 direction);
912 else
913 ret = tce_iommu_build(container, tbl,
914 param.iova >> tbl->it_page_shift,
915 param.vaddr,
916 param.size >> tbl->it_page_shift,
917 direction);
918
919 iommu_flush_tce(tbl);
920
921 return ret;
922 }
923 case VFIO_IOMMU_UNMAP_DMA: {
924 struct vfio_iommu_type1_dma_unmap param;
925 struct iommu_table *tbl = NULL;
926 long num;
927
928 if (!container->enabled)
929 return -EPERM;
930
931 minsz = offsetofend(struct vfio_iommu_type1_dma_unmap,
932 size);
933
934 if (copy_from_user(&param, (void __user *)arg, minsz))
935 return -EFAULT;
936
937 if (param.argsz < minsz)
938 return -EINVAL;
939
940 /* No flag is supported now */
941 if (param.flags)
942 return -EINVAL;
943
944 ret = tce_iommu_create_default_window(container);
945 if (ret)
946 return ret;
947
948 num = tce_iommu_find_table(container, param.iova, &tbl);
949 if (num < 0)
950 return -ENXIO;
951
952 if (param.size & ~IOMMU_PAGE_MASK(tbl))
953 return -EINVAL;
954
955 ret = iommu_tce_clear_param_check(tbl, param.iova, 0,
956 param.size >> tbl->it_page_shift);
957 if (ret)
958 return ret;
959
960 ret = tce_iommu_clear(container, tbl,
961 param.iova >> tbl->it_page_shift,
962 param.size >> tbl->it_page_shift);
963 iommu_flush_tce(tbl);
964
965 return ret;
966 }
967 case VFIO_IOMMU_SPAPR_REGISTER_MEMORY: {
968 struct vfio_iommu_spapr_register_memory param;
969
970 if (!container->v2)
971 break;
972
973 minsz = offsetofend(struct vfio_iommu_spapr_register_memory,
974 size);
975
976 ret = tce_iommu_mm_set(container);
977 if (ret)
978 return ret;
979
980 if (copy_from_user(&param, (void __user *)arg, minsz))
981 return -EFAULT;
982
983 if (param.argsz < minsz)
984 return -EINVAL;
985
986 /* No flag is supported now */
987 if (param.flags)
988 return -EINVAL;
989
990 mutex_lock(&container->lock);
991 ret = tce_iommu_register_pages(container, param.vaddr,
992 param.size);
993 mutex_unlock(&container->lock);
994
995 return ret;
996 }
997 case VFIO_IOMMU_SPAPR_UNREGISTER_MEMORY: {
998 struct vfio_iommu_spapr_register_memory param;
999
1000 if (!container->v2)
1001 break;
1002
1003 if (!container->mm)
1004 return -EPERM;
1005
1006 minsz = offsetofend(struct vfio_iommu_spapr_register_memory,
1007 size);
1008
1009 if (copy_from_user(&param, (void __user *)arg, minsz))
1010 return -EFAULT;
1011
1012 if (param.argsz < minsz)
1013 return -EINVAL;
1014
1015 /* No flag is supported now */
1016 if (param.flags)
1017 return -EINVAL;
1018
1019 mutex_lock(&container->lock);
1020 ret = tce_iommu_unregister_pages(container, param.vaddr,
1021 param.size);
1022 mutex_unlock(&container->lock);
1023
1024 return ret;
1025 }
1026 case VFIO_IOMMU_ENABLE:
1027 if (container->v2)
1028 break;
1029
1030 mutex_lock(&container->lock);
1031 ret = tce_iommu_enable(container);
1032 mutex_unlock(&container->lock);
1033 return ret;
1034
1035
1036 case VFIO_IOMMU_DISABLE:
1037 if (container->v2)
1038 break;
1039
1040 mutex_lock(&container->lock);
1041 tce_iommu_disable(container);
1042 mutex_unlock(&container->lock);
1043 return 0;
1044
1045 case VFIO_EEH_PE_OP: {
1046 struct tce_iommu_group *tcegrp;
1047
1048 ret = 0;
1049 list_for_each_entry(tcegrp, &container->group_list, next) {
1050 ret = vfio_spapr_iommu_eeh_ioctl(tcegrp->grp,
1051 cmd, arg);
1052 if (ret)
1053 return ret;
1054 }
1055 return ret;
1056 }
1057
1058 case VFIO_IOMMU_SPAPR_TCE_CREATE: {
1059 struct vfio_iommu_spapr_tce_create create;
1060
1061 if (!container->v2)
1062 break;
1063
1064 ret = tce_iommu_mm_set(container);
1065 if (ret)
1066 return ret;
1067
1068 if (!tce_groups_attached(container))
1069 return -ENXIO;
1070
1071 minsz = offsetofend(struct vfio_iommu_spapr_tce_create,
1072 start_addr);
1073
1074 if (copy_from_user(&create, (void __user *)arg, minsz))
1075 return -EFAULT;
1076
1077 if (create.argsz < minsz)
1078 return -EINVAL;
1079
1080 if (create.flags)
1081 return -EINVAL;
1082
1083 mutex_lock(&container->lock);
1084
1085 ret = tce_iommu_create_default_window(container);
1086 if (!ret)
1087 ret = tce_iommu_create_window(container,
1088 create.page_shift,
1089 create.window_size, create.levels,
1090 &create.start_addr);
1091
1092 mutex_unlock(&container->lock);
1093
1094 if (!ret && copy_to_user((void __user *)arg, &create, minsz))
1095 ret = -EFAULT;
1096
1097 return ret;
1098 }
1099 case VFIO_IOMMU_SPAPR_TCE_REMOVE: {
1100 struct vfio_iommu_spapr_tce_remove remove;
1101
1102 if (!container->v2)
1103 break;
1104
1105 ret = tce_iommu_mm_set(container);
1106 if (ret)
1107 return ret;
1108
1109 if (!tce_groups_attached(container))
1110 return -ENXIO;
1111
1112 minsz = offsetofend(struct vfio_iommu_spapr_tce_remove,
1113 start_addr);
1114
1115 if (copy_from_user(&remove, (void __user *)arg, minsz))
1116 return -EFAULT;
1117
1118 if (remove.argsz < minsz)
1119 return -EINVAL;
1120
1121 if (remove.flags)
1122 return -EINVAL;
1123
1124 if (container->def_window_pending && !remove.start_addr) {
1125 container->def_window_pending = false;
1126 return 0;
1127 }
1128
1129 mutex_lock(&container->lock);
1130
1131 ret = tce_iommu_remove_window(container, remove.start_addr);
1132
1133 mutex_unlock(&container->lock);
1134
1135 return ret;
1136 }
1137 }
1138
1139 return -ENOTTY;
1140 }
1141
1142 static void tce_iommu_release_ownership(struct tce_container *container,
1143 struct iommu_table_group *table_group)
1144 {
1145 int i;
1146
1147 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) {
1148 struct iommu_table *tbl = container->tables[i];
1149
1150 if (!tbl)
1151 continue;
1152
1153 tce_iommu_clear(container, tbl, tbl->it_offset, tbl->it_size);
1154 if (tbl->it_map)
1155 iommu_release_ownership(tbl);
1156
1157 container->tables[i] = NULL;
1158 }
1159 }
1160
1161 static int tce_iommu_take_ownership(struct tce_container *container,
1162 struct iommu_table_group *table_group)
1163 {
1164 int i, j, rc = 0;
1165
1166 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) {
1167 struct iommu_table *tbl = table_group->tables[i];
1168
1169 if (!tbl || !tbl->it_map)
1170 continue;
1171
1172 rc = iommu_take_ownership(tbl);
1173 if (rc) {
1174 for (j = 0; j < i; ++j)
1175 iommu_release_ownership(
1176 table_group->tables[j]);
1177
1178 return rc;
1179 }
1180 }
1181
1182 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i)
1183 container->tables[i] = table_group->tables[i];
1184
1185 return 0;
1186 }
1187
1188 static void tce_iommu_release_ownership_ddw(struct tce_container *container,
1189 struct iommu_table_group *table_group)
1190 {
1191 long i;
1192
1193 if (!table_group->ops->unset_window) {
1194 WARN_ON_ONCE(1);
1195 return;
1196 }
1197
1198 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i)
1199 table_group->ops->unset_window(table_group, i);
1200
1201 table_group->ops->release_ownership(table_group);
1202 }
1203
1204 static long tce_iommu_take_ownership_ddw(struct tce_container *container,
1205 struct iommu_table_group *table_group)
1206 {
1207 long i, ret = 0;
1208
1209 if (!table_group->ops->create_table || !table_group->ops->set_window ||
1210 !table_group->ops->release_ownership) {
1211 WARN_ON_ONCE(1);
1212 return -EFAULT;
1213 }
1214
1215 table_group->ops->take_ownership(table_group);
1216
1217 /* Set all windows to the new group */
1218 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) {
1219 struct iommu_table *tbl = container->tables[i];
1220
1221 if (!tbl)
1222 continue;
1223
1224 ret = table_group->ops->set_window(table_group, i, tbl);
1225 if (ret)
1226 goto release_exit;
1227 }
1228
1229 return 0;
1230
1231 release_exit:
1232 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i)
1233 table_group->ops->unset_window(table_group, i);
1234
1235 table_group->ops->release_ownership(table_group);
1236
1237 return ret;
1238 }
1239
1240 static int tce_iommu_attach_group(void *iommu_data,
1241 struct iommu_group *iommu_group)
1242 {
1243 int ret;
1244 struct tce_container *container = iommu_data;
1245 struct iommu_table_group *table_group;
1246 struct tce_iommu_group *tcegrp = NULL;
1247
1248 mutex_lock(&container->lock);
1249
1250 /* pr_debug("tce_vfio: Attaching group #%u to iommu %p\n",
1251 iommu_group_id(iommu_group), iommu_group); */
1252 table_group = iommu_group_get_iommudata(iommu_group);
1253 if (!table_group) {
1254 ret = -ENODEV;
1255 goto unlock_exit;
1256 }
1257
1258 if (tce_groups_attached(container) && (!table_group->ops ||
1259 !table_group->ops->take_ownership ||
1260 !table_group->ops->release_ownership)) {
1261 ret = -EBUSY;
1262 goto unlock_exit;
1263 }
1264
1265 /* Check if new group has the same iommu_ops (i.e. compatible) */
1266 list_for_each_entry(tcegrp, &container->group_list, next) {
1267 struct iommu_table_group *table_group_tmp;
1268
1269 if (tcegrp->grp == iommu_group) {
1270 pr_warn("tce_vfio: Group %d is already attached\n",
1271 iommu_group_id(iommu_group));
1272 ret = -EBUSY;
1273 goto unlock_exit;
1274 }
1275 table_group_tmp = iommu_group_get_iommudata(tcegrp->grp);
1276 if (table_group_tmp->ops->create_table !=
1277 table_group->ops->create_table) {
1278 pr_warn("tce_vfio: Group %d is incompatible with group %d\n",
1279 iommu_group_id(iommu_group),
1280 iommu_group_id(tcegrp->grp));
1281 ret = -EPERM;
1282 goto unlock_exit;
1283 }
1284 }
1285
1286 tcegrp = kzalloc(sizeof(*tcegrp), GFP_KERNEL);
1287 if (!tcegrp) {
1288 ret = -ENOMEM;
1289 goto unlock_exit;
1290 }
1291
1292 if (!table_group->ops || !table_group->ops->take_ownership ||
1293 !table_group->ops->release_ownership) {
1294 if (container->v2) {
1295 ret = -EPERM;
1296 goto unlock_exit;
1297 }
1298 ret = tce_iommu_take_ownership(container, table_group);
1299 } else {
1300 if (!container->v2) {
1301 ret = -EPERM;
1302 goto unlock_exit;
1303 }
1304 ret = tce_iommu_take_ownership_ddw(container, table_group);
1305 if (!tce_groups_attached(container) && !container->tables[0])
1306 container->def_window_pending = true;
1307 }
1308
1309 if (!ret) {
1310 tcegrp->grp = iommu_group;
1311 list_add(&tcegrp->next, &container->group_list);
1312 }
1313
1314 unlock_exit:
1315 if (ret && tcegrp)
1316 kfree(tcegrp);
1317
1318 mutex_unlock(&container->lock);
1319
1320 return ret;
1321 }
1322
1323 static void tce_iommu_detach_group(void *iommu_data,
1324 struct iommu_group *iommu_group)
1325 {
1326 struct tce_container *container = iommu_data;
1327 struct iommu_table_group *table_group;
1328 bool found = false;
1329 struct tce_iommu_group *tcegrp;
1330
1331 mutex_lock(&container->lock);
1332
1333 list_for_each_entry(tcegrp, &container->group_list, next) {
1334 if (tcegrp->grp == iommu_group) {
1335 found = true;
1336 break;
1337 }
1338 }
1339
1340 if (!found) {
1341 pr_warn("tce_vfio: detaching unattached group #%u\n",
1342 iommu_group_id(iommu_group));
1343 goto unlock_exit;
1344 }
1345
1346 list_del(&tcegrp->next);
1347 kfree(tcegrp);
1348
1349 table_group = iommu_group_get_iommudata(iommu_group);
1350 BUG_ON(!table_group);
1351
1352 if (!table_group->ops || !table_group->ops->release_ownership)
1353 tce_iommu_release_ownership(container, table_group);
1354 else
1355 tce_iommu_release_ownership_ddw(container, table_group);
1356
1357 unlock_exit:
1358 mutex_unlock(&container->lock);
1359 }
1360
1361 const struct vfio_iommu_driver_ops tce_iommu_driver_ops = {
1362 .name = "iommu-vfio-powerpc",
1363 .owner = THIS_MODULE,
1364 .open = tce_iommu_open,
1365 .release = tce_iommu_release,
1366 .ioctl = tce_iommu_ioctl,
1367 .attach_group = tce_iommu_attach_group,
1368 .detach_group = tce_iommu_detach_group,
1369 };
1370
1371 static int __init tce_iommu_init(void)
1372 {
1373 return vfio_register_iommu_driver(&tce_iommu_driver_ops);
1374 }
1375
1376 static void __exit tce_iommu_cleanup(void)
1377 {
1378 vfio_unregister_iommu_driver(&tce_iommu_driver_ops);
1379 }
1380
1381 module_init(tce_iommu_init);
1382 module_exit(tce_iommu_cleanup);
1383
1384 MODULE_VERSION(DRIVER_VERSION);
1385 MODULE_LICENSE("GPL v2");
1386 MODULE_AUTHOR(DRIVER_AUTHOR);
1387 MODULE_DESCRIPTION(DRIVER_DESC);
1388
Linux with added FPC-III support