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Merge tag 'clang-format-for-linus-v5.1-rc5' of git://github.com/ojeda/linux
[thirdparty/kernel/stable.git] / drivers / vfio / vfio_iommu_spapr_tce.c
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 long ret;
156
157 if ((vaddr & ~PAGE_MASK) || (size & ~PAGE_MASK))
158 return -EINVAL;
159
160 mem = mm_iommu_get(container->mm, vaddr, size >> PAGE_SHIFT);
161 if (!mem)
162 return -ENOENT;
163
164 list_for_each_entry(tcemem, &container->prereg_list, next) {
165 if (tcemem->mem == mem) {
166 found = true;
167 break;
168 }
169 }
170
171 if (!found)
172 ret = -ENOENT;
173 else
174 ret = tce_iommu_prereg_free(container, tcemem);
175
176 mm_iommu_put(container->mm, mem);
177
178 return ret;
179 }
180
181 static long tce_iommu_register_pages(struct tce_container *container,
182 __u64 vaddr, __u64 size)
183 {
184 long ret = 0;
185 struct mm_iommu_table_group_mem_t *mem = NULL;
186 struct tce_iommu_prereg *tcemem;
187 unsigned long entries = size >> PAGE_SHIFT;
188
189 if ((vaddr & ~PAGE_MASK) || (size & ~PAGE_MASK) ||
190 ((vaddr + size) < vaddr))
191 return -EINVAL;
192
193 mem = mm_iommu_get(container->mm, vaddr, entries);
194 if (mem) {
195 list_for_each_entry(tcemem, &container->prereg_list, next) {
196 if (tcemem->mem == mem) {
197 ret = -EBUSY;
198 goto put_exit;
199 }
200 }
201 } else {
202 ret = mm_iommu_new(container->mm, vaddr, entries, &mem);
203 if (ret)
204 return ret;
205 }
206
207 tcemem = kzalloc(sizeof(*tcemem), GFP_KERNEL);
208 if (!tcemem) {
209 ret = -ENOMEM;
210 goto put_exit;
211 }
212
213 tcemem->mem = mem;
214 list_add(&tcemem->next, &container->prereg_list);
215
216 container->enabled = true;
217
218 return 0;
219
220 put_exit:
221 mm_iommu_put(container->mm, mem);
222 return ret;
223 }
224
225 static bool tce_page_is_contained(struct mm_struct *mm, unsigned long hpa,
226 unsigned int page_shift)
227 {
228 struct page *page;
229 unsigned long size = 0;
230
231 if (mm_iommu_is_devmem(mm, hpa, page_shift, &size))
232 return size == (1UL << page_shift);
233
234 page = pfn_to_page(hpa >> PAGE_SHIFT);
235 /*
236 * Check that the TCE table granularity is not bigger than the size of
237 * a page we just found. Otherwise the hardware can get access to
238 * a bigger memory chunk that it should.
239 */
240 return (PAGE_SHIFT + compound_order(compound_head(page))) >= page_shift;
241 }
242
243 static inline bool tce_groups_attached(struct tce_container *container)
244 {
245 return !list_empty(&container->group_list);
246 }
247
248 static long tce_iommu_find_table(struct tce_container *container,
249 phys_addr_t ioba, struct iommu_table **ptbl)
250 {
251 long i;
252
253 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) {
254 struct iommu_table *tbl = container->tables[i];
255
256 if (tbl) {
257 unsigned long entry = ioba >> tbl->it_page_shift;
258 unsigned long start = tbl->it_offset;
259 unsigned long end = start + tbl->it_size;
260
261 if ((start <= entry) && (entry < end)) {
262 *ptbl = tbl;
263 return i;
264 }
265 }
266 }
267
268 return -1;
269 }
270
271 static int tce_iommu_find_free_table(struct tce_container *container)
272 {
273 int i;
274
275 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) {
276 if (!container->tables[i])
277 return i;
278 }
279
280 return -ENOSPC;
281 }
282
283 static int tce_iommu_enable(struct tce_container *container)
284 {
285 int ret = 0;
286 unsigned long locked;
287 struct iommu_table_group *table_group;
288 struct tce_iommu_group *tcegrp;
289
290 if (container->enabled)
291 return -EBUSY;
292
293 /*
294 * When userspace pages are mapped into the IOMMU, they are effectively
295 * locked memory, so, theoretically, we need to update the accounting
296 * of locked pages on each map and unmap. For powerpc, the map unmap
297 * paths can be very hot, though, and the accounting would kill
298 * performance, especially since it would be difficult to impossible
299 * to handle the accounting in real mode only.
300 *
301 * To address that, rather than precisely accounting every page, we
302 * instead account for a worst case on locked memory when the iommu is
303 * enabled and disabled. The worst case upper bound on locked memory
304 * is the size of the whole iommu window, which is usually relatively
305 * small (compared to total memory sizes) on POWER hardware.
306 *
307 * Also we don't have a nice way to fail on H_PUT_TCE due to ulimits,
308 * that would effectively kill the guest at random points, much better
309 * enforcing the limit based on the max that the guest can map.
310 *
311 * Unfortunately at the moment it counts whole tables, no matter how
312 * much memory the guest has. I.e. for 4GB guest and 4 IOMMU groups
313 * each with 2GB DMA window, 8GB will be counted here. The reason for
314 * this is that we cannot tell here the amount of RAM used by the guest
315 * as this information is only available from KVM and VFIO is
316 * KVM agnostic.
317 *
318 * So we do not allow enabling a container without a group attached
319 * as there is no way to know how much we should increment
320 * the locked_vm counter.
321 */
322 if (!tce_groups_attached(container))
323 return -ENODEV;
324
325 tcegrp = list_first_entry(&container->group_list,
326 struct tce_iommu_group, next);
327 table_group = iommu_group_get_iommudata(tcegrp->grp);
328 if (!table_group)
329 return -ENODEV;
330
331 if (!table_group->tce32_size)
332 return -EPERM;
333
334 ret = tce_iommu_mm_set(container);
335 if (ret)
336 return ret;
337
338 locked = table_group->tce32_size >> PAGE_SHIFT;
339 ret = try_increment_locked_vm(container->mm, locked);
340 if (ret)
341 return ret;
342
343 container->locked_pages = locked;
344
345 container->enabled = true;
346
347 return ret;
348 }
349
350 static void tce_iommu_disable(struct tce_container *container)
351 {
352 if (!container->enabled)
353 return;
354
355 container->enabled = false;
356
357 BUG_ON(!container->mm);
358 decrement_locked_vm(container->mm, container->locked_pages);
359 }
360
361 static void *tce_iommu_open(unsigned long arg)
362 {
363 struct tce_container *container;
364
365 if ((arg != VFIO_SPAPR_TCE_IOMMU) && (arg != VFIO_SPAPR_TCE_v2_IOMMU)) {
366 pr_err("tce_vfio: Wrong IOMMU type\n");
367 return ERR_PTR(-EINVAL);
368 }
369
370 container = kzalloc(sizeof(*container), GFP_KERNEL);
371 if (!container)
372 return ERR_PTR(-ENOMEM);
373
374 mutex_init(&container->lock);
375 INIT_LIST_HEAD_RCU(&container->group_list);
376 INIT_LIST_HEAD_RCU(&container->prereg_list);
377
378 container->v2 = arg == VFIO_SPAPR_TCE_v2_IOMMU;
379
380 return container;
381 }
382
383 static int tce_iommu_clear(struct tce_container *container,
384 struct iommu_table *tbl,
385 unsigned long entry, unsigned long pages);
386 static void tce_iommu_free_table(struct tce_container *container,
387 struct iommu_table *tbl);
388
389 static void tce_iommu_release(void *iommu_data)
390 {
391 struct tce_container *container = iommu_data;
392 struct tce_iommu_group *tcegrp;
393 struct tce_iommu_prereg *tcemem, *tmtmp;
394 long i;
395
396 while (tce_groups_attached(container)) {
397 tcegrp = list_first_entry(&container->group_list,
398 struct tce_iommu_group, next);
399 tce_iommu_detach_group(iommu_data, tcegrp->grp);
400 }
401
402 /*
403 * If VFIO created a table, it was not disposed
404 * by tce_iommu_detach_group() so do it now.
405 */
406 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) {
407 struct iommu_table *tbl = container->tables[i];
408
409 if (!tbl)
410 continue;
411
412 tce_iommu_clear(container, tbl, tbl->it_offset, tbl->it_size);
413 tce_iommu_free_table(container, tbl);
414 }
415
416 list_for_each_entry_safe(tcemem, tmtmp, &container->prereg_list, next)
417 WARN_ON(tce_iommu_prereg_free(container, tcemem));
418
419 tce_iommu_disable(container);
420 if (container->mm)
421 mmdrop(container->mm);
422 mutex_destroy(&container->lock);
423
424 kfree(container);
425 }
426
427 static void tce_iommu_unuse_page(struct tce_container *container,
428 unsigned long hpa)
429 {
430 struct page *page;
431
432 page = pfn_to_page(hpa >> PAGE_SHIFT);
433 put_page(page);
434 }
435
436 static int tce_iommu_prereg_ua_to_hpa(struct tce_container *container,
437 unsigned long tce, unsigned long shift,
438 unsigned long *phpa, struct mm_iommu_table_group_mem_t **pmem)
439 {
440 long ret = 0;
441 struct mm_iommu_table_group_mem_t *mem;
442
443 mem = mm_iommu_lookup(container->mm, tce, 1ULL << shift);
444 if (!mem)
445 return -EINVAL;
446
447 ret = mm_iommu_ua_to_hpa(mem, tce, shift, phpa);
448 if (ret)
449 return -EINVAL;
450
451 *pmem = mem;
452
453 return 0;
454 }
455
456 static void tce_iommu_unuse_page_v2(struct tce_container *container,
457 struct iommu_table *tbl, unsigned long entry)
458 {
459 struct mm_iommu_table_group_mem_t *mem = NULL;
460 int ret;
461 unsigned long hpa = 0;
462 __be64 *pua = IOMMU_TABLE_USERSPACE_ENTRY_RO(tbl, entry);
463
464 if (!pua)
465 return;
466
467 ret = tce_iommu_prereg_ua_to_hpa(container, be64_to_cpu(*pua),
468 tbl->it_page_shift, &hpa, &mem);
469 if (ret)
470 pr_debug("%s: tce %llx at #%lx was not cached, ret=%d\n",
471 __func__, be64_to_cpu(*pua), entry, ret);
472 if (mem)
473 mm_iommu_mapped_dec(mem);
474
475 *pua = cpu_to_be64(0);
476 }
477
478 static int tce_iommu_clear(struct tce_container *container,
479 struct iommu_table *tbl,
480 unsigned long entry, unsigned long pages)
481 {
482 unsigned long oldhpa;
483 long ret;
484 enum dma_data_direction direction;
485 unsigned long lastentry = entry + pages;
486
487 for ( ; entry < lastentry; ++entry) {
488 if (tbl->it_indirect_levels && tbl->it_userspace) {
489 /*
490 * For multilevel tables, we can take a shortcut here
491 * and skip some TCEs as we know that the userspace
492 * addresses cache is a mirror of the real TCE table
493 * and if it is missing some indirect levels, then
494 * the hardware table does not have them allocated
495 * either and therefore does not require updating.
496 */
497 __be64 *pua = IOMMU_TABLE_USERSPACE_ENTRY_RO(tbl,
498 entry);
499 if (!pua) {
500 /* align to level_size which is power of two */
501 entry |= tbl->it_level_size - 1;
502 continue;
503 }
504 }
505
506 cond_resched();
507
508 direction = DMA_NONE;
509 oldhpa = 0;
510 ret = iommu_tce_xchg(container->mm, tbl, entry, &oldhpa,
511 &direction);
512 if (ret)
513 continue;
514
515 if (direction == DMA_NONE)
516 continue;
517
518 if (container->v2) {
519 tce_iommu_unuse_page_v2(container, tbl, entry);
520 continue;
521 }
522
523 tce_iommu_unuse_page(container, oldhpa);
524 }
525
526 return 0;
527 }
528
529 static int tce_iommu_use_page(unsigned long tce, unsigned long *hpa)
530 {
531 struct page *page = NULL;
532 enum dma_data_direction direction = iommu_tce_direction(tce);
533
534 if (get_user_pages_fast(tce & PAGE_MASK, 1,
535 direction != DMA_TO_DEVICE, &page) != 1)
536 return -EFAULT;
537
538 *hpa = __pa((unsigned long) page_address(page));
539
540 return 0;
541 }
542
543 static long tce_iommu_build(struct tce_container *container,
544 struct iommu_table *tbl,
545 unsigned long entry, unsigned long tce, unsigned long pages,
546 enum dma_data_direction direction)
547 {
548 long i, ret = 0;
549 unsigned long hpa;
550 enum dma_data_direction dirtmp;
551
552 for (i = 0; i < pages; ++i) {
553 unsigned long offset = tce & IOMMU_PAGE_MASK(tbl) & ~PAGE_MASK;
554
555 ret = tce_iommu_use_page(tce, &hpa);
556 if (ret)
557 break;
558
559 if (!tce_page_is_contained(container->mm, hpa,
560 tbl->it_page_shift)) {
561 ret = -EPERM;
562 break;
563 }
564
565 hpa |= offset;
566 dirtmp = direction;
567 ret = iommu_tce_xchg(container->mm, tbl, entry + i, &hpa,
568 &dirtmp);
569 if (ret) {
570 tce_iommu_unuse_page(container, hpa);
571 pr_err("iommu_tce: %s failed ioba=%lx, tce=%lx, ret=%ld\n",
572 __func__, entry << tbl->it_page_shift,
573 tce, ret);
574 break;
575 }
576
577 if (dirtmp != DMA_NONE)
578 tce_iommu_unuse_page(container, hpa);
579
580 tce += IOMMU_PAGE_SIZE(tbl);
581 }
582
583 if (ret)
584 tce_iommu_clear(container, tbl, entry, i);
585
586 return ret;
587 }
588
589 static long tce_iommu_build_v2(struct tce_container *container,
590 struct iommu_table *tbl,
591 unsigned long entry, unsigned long tce, unsigned long pages,
592 enum dma_data_direction direction)
593 {
594 long i, ret = 0;
595 unsigned long hpa;
596 enum dma_data_direction dirtmp;
597
598 for (i = 0; i < pages; ++i) {
599 struct mm_iommu_table_group_mem_t *mem = NULL;
600 __be64 *pua = IOMMU_TABLE_USERSPACE_ENTRY(tbl, entry + i);
601
602 ret = tce_iommu_prereg_ua_to_hpa(container,
603 tce, tbl->it_page_shift, &hpa, &mem);
604 if (ret)
605 break;
606
607 if (!tce_page_is_contained(container->mm, hpa,
608 tbl->it_page_shift)) {
609 ret = -EPERM;
610 break;
611 }
612
613 /* Preserve offset within IOMMU page */
614 hpa |= tce & IOMMU_PAGE_MASK(tbl) & ~PAGE_MASK;
615 dirtmp = direction;
616
617 /* The registered region is being unregistered */
618 if (mm_iommu_mapped_inc(mem))
619 break;
620
621 ret = iommu_tce_xchg(container->mm, tbl, entry + i, &hpa,
622 &dirtmp);
623 if (ret) {
624 /* dirtmp cannot be DMA_NONE here */
625 tce_iommu_unuse_page_v2(container, tbl, entry + i);
626 pr_err("iommu_tce: %s failed ioba=%lx, tce=%lx, ret=%ld\n",
627 __func__, entry << tbl->it_page_shift,
628 tce, ret);
629 break;
630 }
631
632 if (dirtmp != DMA_NONE)
633 tce_iommu_unuse_page_v2(container, tbl, entry + i);
634
635 *pua = cpu_to_be64(tce);
636
637 tce += IOMMU_PAGE_SIZE(tbl);
638 }
639
640 if (ret)
641 tce_iommu_clear(container, tbl, entry, i);
642
643 return ret;
644 }
645
646 static long tce_iommu_create_table(struct tce_container *container,
647 struct iommu_table_group *table_group,
648 int num,
649 __u32 page_shift,
650 __u64 window_size,
651 __u32 levels,
652 struct iommu_table **ptbl)
653 {
654 long ret, table_size;
655
656 table_size = table_group->ops->get_table_size(page_shift, window_size,
657 levels);
658 if (!table_size)
659 return -EINVAL;
660
661 ret = try_increment_locked_vm(container->mm, table_size >> PAGE_SHIFT);
662 if (ret)
663 return ret;
664
665 ret = table_group->ops->create_table(table_group, num,
666 page_shift, window_size, levels, ptbl);
667
668 WARN_ON(!ret && !(*ptbl)->it_ops->free);
669 WARN_ON(!ret && ((*ptbl)->it_allocated_size > table_size));
670
671 return ret;
672 }
673
674 static void tce_iommu_free_table(struct tce_container *container,
675 struct iommu_table *tbl)
676 {
677 unsigned long pages = tbl->it_allocated_size >> PAGE_SHIFT;
678
679 iommu_tce_table_put(tbl);
680 decrement_locked_vm(container->mm, pages);
681 }
682
683 static long tce_iommu_create_window(struct tce_container *container,
684 __u32 page_shift, __u64 window_size, __u32 levels,
685 __u64 *start_addr)
686 {
687 struct tce_iommu_group *tcegrp;
688 struct iommu_table_group *table_group;
689 struct iommu_table *tbl = NULL;
690 long ret, num;
691
692 num = tce_iommu_find_free_table(container);
693 if (num < 0)
694 return num;
695
696 /* Get the first group for ops::create_table */
697 tcegrp = list_first_entry(&container->group_list,
698 struct tce_iommu_group, next);
699 table_group = iommu_group_get_iommudata(tcegrp->grp);
700 if (!table_group)
701 return -EFAULT;
702
703 if (!(table_group->pgsizes & (1ULL << page_shift)))
704 return -EINVAL;
705
706 if (!table_group->ops->set_window || !table_group->ops->unset_window ||
707 !table_group->ops->get_table_size ||
708 !table_group->ops->create_table)
709 return -EPERM;
710
711 /* Create TCE table */
712 ret = tce_iommu_create_table(container, table_group, num,
713 page_shift, window_size, levels, &tbl);
714 if (ret)
715 return ret;
716
717 BUG_ON(!tbl->it_ops->free);
718
719 /*
720 * Program the table to every group.
721 * Groups have been tested for compatibility at the attach time.
722 */
723 list_for_each_entry(tcegrp, &container->group_list, next) {
724 table_group = iommu_group_get_iommudata(tcegrp->grp);
725
726 ret = table_group->ops->set_window(table_group, num, tbl);
727 if (ret)
728 goto unset_exit;
729 }
730
731 container->tables[num] = tbl;
732
733 /* Return start address assigned by platform in create_table() */
734 *start_addr = tbl->it_offset << tbl->it_page_shift;
735
736 return 0;
737
738 unset_exit:
739 list_for_each_entry(tcegrp, &container->group_list, next) {
740 table_group = iommu_group_get_iommudata(tcegrp->grp);
741 table_group->ops->unset_window(table_group, num);
742 }
743 tce_iommu_free_table(container, tbl);
744
745 return ret;
746 }
747
748 static long tce_iommu_remove_window(struct tce_container *container,
749 __u64 start_addr)
750 {
751 struct iommu_table_group *table_group = NULL;
752 struct iommu_table *tbl;
753 struct tce_iommu_group *tcegrp;
754 int num;
755
756 num = tce_iommu_find_table(container, start_addr, &tbl);
757 if (num < 0)
758 return -EINVAL;
759
760 BUG_ON(!tbl->it_size);
761
762 /* Detach groups from IOMMUs */
763 list_for_each_entry(tcegrp, &container->group_list, next) {
764 table_group = iommu_group_get_iommudata(tcegrp->grp);
765
766 /*
767 * SPAPR TCE IOMMU exposes the default DMA window to
768 * the guest via dma32_window_start/size of
769 * VFIO_IOMMU_SPAPR_TCE_GET_INFO. Some platforms allow
770 * the userspace to remove this window, some do not so
771 * here we check for the platform capability.
772 */
773 if (!table_group->ops || !table_group->ops->unset_window)
774 return -EPERM;
775
776 table_group->ops->unset_window(table_group, num);
777 }
778
779 /* Free table */
780 tce_iommu_clear(container, tbl, tbl->it_offset, tbl->it_size);
781 tce_iommu_free_table(container, tbl);
782 container->tables[num] = NULL;
783
784 return 0;
785 }
786
787 static long tce_iommu_create_default_window(struct tce_container *container)
788 {
789 long ret;
790 __u64 start_addr = 0;
791 struct tce_iommu_group *tcegrp;
792 struct iommu_table_group *table_group;
793
794 if (!container->def_window_pending)
795 return 0;
796
797 if (!tce_groups_attached(container))
798 return -ENODEV;
799
800 tcegrp = list_first_entry(&container->group_list,
801 struct tce_iommu_group, next);
802 table_group = iommu_group_get_iommudata(tcegrp->grp);
803 if (!table_group)
804 return -ENODEV;
805
806 ret = tce_iommu_create_window(container, IOMMU_PAGE_SHIFT_4K,
807 table_group->tce32_size, 1, &start_addr);
808 WARN_ON_ONCE(!ret && start_addr);
809
810 if (!ret)
811 container->def_window_pending = false;
812
813 return ret;
814 }
815
816 static long tce_iommu_ioctl(void *iommu_data,
817 unsigned int cmd, unsigned long arg)
818 {
819 struct tce_container *container = iommu_data;
820 unsigned long minsz, ddwsz;
821 long ret;
822
823 switch (cmd) {
824 case VFIO_CHECK_EXTENSION:
825 switch (arg) {
826 case VFIO_SPAPR_TCE_IOMMU:
827 case VFIO_SPAPR_TCE_v2_IOMMU:
828 ret = 1;
829 break;
830 default:
831 ret = vfio_spapr_iommu_eeh_ioctl(NULL, cmd, arg);
832 break;
833 }
834
835 return (ret < 0) ? 0 : ret;
836 }
837
838 /*
839 * Sanity check to prevent one userspace from manipulating
840 * another userspace mm.
841 */
842 BUG_ON(!container);
843 if (container->mm && container->mm != current->mm)
844 return -EPERM;
845
846 switch (cmd) {
847 case VFIO_IOMMU_SPAPR_TCE_GET_INFO: {
848 struct vfio_iommu_spapr_tce_info info;
849 struct tce_iommu_group *tcegrp;
850 struct iommu_table_group *table_group;
851
852 if (!tce_groups_attached(container))
853 return -ENXIO;
854
855 tcegrp = list_first_entry(&container->group_list,
856 struct tce_iommu_group, next);
857 table_group = iommu_group_get_iommudata(tcegrp->grp);
858
859 if (!table_group)
860 return -ENXIO;
861
862 minsz = offsetofend(struct vfio_iommu_spapr_tce_info,
863 dma32_window_size);
864
865 if (copy_from_user(&info, (void __user *)arg, minsz))
866 return -EFAULT;
867
868 if (info.argsz < minsz)
869 return -EINVAL;
870
871 info.dma32_window_start = table_group->tce32_start;
872 info.dma32_window_size = table_group->tce32_size;
873 info.flags = 0;
874 memset(&info.ddw, 0, sizeof(info.ddw));
875
876 if (table_group->max_dynamic_windows_supported &&
877 container->v2) {
878 info.flags |= VFIO_IOMMU_SPAPR_INFO_DDW;
879 info.ddw.pgsizes = table_group->pgsizes;
880 info.ddw.max_dynamic_windows_supported =
881 table_group->max_dynamic_windows_supported;
882 info.ddw.levels = table_group->max_levels;
883 }
884
885 ddwsz = offsetofend(struct vfio_iommu_spapr_tce_info, ddw);
886
887 if (info.argsz >= ddwsz)
888 minsz = ddwsz;
889
890 if (copy_to_user((void __user *)arg, &info, minsz))
891 return -EFAULT;
892
893 return 0;
894 }
895 case VFIO_IOMMU_MAP_DMA: {
896 struct vfio_iommu_type1_dma_map param;
897 struct iommu_table *tbl = NULL;
898 long num;
899 enum dma_data_direction direction;
900
901 if (!container->enabled)
902 return -EPERM;
903
904 minsz = offsetofend(struct vfio_iommu_type1_dma_map, size);
905
906 if (copy_from_user(&param, (void __user *)arg, minsz))
907 return -EFAULT;
908
909 if (param.argsz < minsz)
910 return -EINVAL;
911
912 if (param.flags & ~(VFIO_DMA_MAP_FLAG_READ |
913 VFIO_DMA_MAP_FLAG_WRITE))
914 return -EINVAL;
915
916 ret = tce_iommu_create_default_window(container);
917 if (ret)
918 return ret;
919
920 num = tce_iommu_find_table(container, param.iova, &tbl);
921 if (num < 0)
922 return -ENXIO;
923
924 if ((param.size & ~IOMMU_PAGE_MASK(tbl)) ||
925 (param.vaddr & ~IOMMU_PAGE_MASK(tbl)))
926 return -EINVAL;
927
928 /* iova is checked by the IOMMU API */
929 if (param.flags & VFIO_DMA_MAP_FLAG_READ) {
930 if (param.flags & VFIO_DMA_MAP_FLAG_WRITE)
931 direction = DMA_BIDIRECTIONAL;
932 else
933 direction = DMA_TO_DEVICE;
934 } else {
935 if (param.flags & VFIO_DMA_MAP_FLAG_WRITE)
936 direction = DMA_FROM_DEVICE;
937 else
938 return -EINVAL;
939 }
940
941 ret = iommu_tce_put_param_check(tbl, param.iova, param.vaddr);
942 if (ret)
943 return ret;
944
945 if (container->v2)
946 ret = tce_iommu_build_v2(container, tbl,
947 param.iova >> tbl->it_page_shift,
948 param.vaddr,
949 param.size >> tbl->it_page_shift,
950 direction);
951 else
952 ret = tce_iommu_build(container, tbl,
953 param.iova >> tbl->it_page_shift,
954 param.vaddr,
955 param.size >> tbl->it_page_shift,
956 direction);
957
958 iommu_flush_tce(tbl);
959
960 return ret;
961 }
962 case VFIO_IOMMU_UNMAP_DMA: {
963 struct vfio_iommu_type1_dma_unmap param;
964 struct iommu_table *tbl = NULL;
965 long num;
966
967 if (!container->enabled)
968 return -EPERM;
969
970 minsz = offsetofend(struct vfio_iommu_type1_dma_unmap,
971 size);
972
973 if (copy_from_user(&param, (void __user *)arg, minsz))
974 return -EFAULT;
975
976 if (param.argsz < minsz)
977 return -EINVAL;
978
979 /* No flag is supported now */
980 if (param.flags)
981 return -EINVAL;
982
983 ret = tce_iommu_create_default_window(container);
984 if (ret)
985 return ret;
986
987 num = tce_iommu_find_table(container, param.iova, &tbl);
988 if (num < 0)
989 return -ENXIO;
990
991 if (param.size & ~IOMMU_PAGE_MASK(tbl))
992 return -EINVAL;
993
994 ret = iommu_tce_clear_param_check(tbl, param.iova, 0,
995 param.size >> tbl->it_page_shift);
996 if (ret)
997 return ret;
998
999 ret = tce_iommu_clear(container, tbl,
1000 param.iova >> tbl->it_page_shift,
1001 param.size >> tbl->it_page_shift);
1002 iommu_flush_tce(tbl);
1003
1004 return ret;
1005 }
1006 case VFIO_IOMMU_SPAPR_REGISTER_MEMORY: {
1007 struct vfio_iommu_spapr_register_memory param;
1008
1009 if (!container->v2)
1010 break;
1011
1012 minsz = offsetofend(struct vfio_iommu_spapr_register_memory,
1013 size);
1014
1015 ret = tce_iommu_mm_set(container);
1016 if (ret)
1017 return ret;
1018
1019 if (copy_from_user(&param, (void __user *)arg, minsz))
1020 return -EFAULT;
1021
1022 if (param.argsz < minsz)
1023 return -EINVAL;
1024
1025 /* No flag is supported now */
1026 if (param.flags)
1027 return -EINVAL;
1028
1029 mutex_lock(&container->lock);
1030 ret = tce_iommu_register_pages(container, param.vaddr,
1031 param.size);
1032 mutex_unlock(&container->lock);
1033
1034 return ret;
1035 }
1036 case VFIO_IOMMU_SPAPR_UNREGISTER_MEMORY: {
1037 struct vfio_iommu_spapr_register_memory param;
1038
1039 if (!container->v2)
1040 break;
1041
1042 if (!container->mm)
1043 return -EPERM;
1044
1045 minsz = offsetofend(struct vfio_iommu_spapr_register_memory,
1046 size);
1047
1048 if (copy_from_user(&param, (void __user *)arg, minsz))
1049 return -EFAULT;
1050
1051 if (param.argsz < minsz)
1052 return -EINVAL;
1053
1054 /* No flag is supported now */
1055 if (param.flags)
1056 return -EINVAL;
1057
1058 mutex_lock(&container->lock);
1059 ret = tce_iommu_unregister_pages(container, param.vaddr,
1060 param.size);
1061 mutex_unlock(&container->lock);
1062
1063 return ret;
1064 }
1065 case VFIO_IOMMU_ENABLE:
1066 if (container->v2)
1067 break;
1068
1069 mutex_lock(&container->lock);
1070 ret = tce_iommu_enable(container);
1071 mutex_unlock(&container->lock);
1072 return ret;
1073
1074
1075 case VFIO_IOMMU_DISABLE:
1076 if (container->v2)
1077 break;
1078
1079 mutex_lock(&container->lock);
1080 tce_iommu_disable(container);
1081 mutex_unlock(&container->lock);
1082 return 0;
1083
1084 case VFIO_EEH_PE_OP: {
1085 struct tce_iommu_group *tcegrp;
1086
1087 ret = 0;
1088 list_for_each_entry(tcegrp, &container->group_list, next) {
1089 ret = vfio_spapr_iommu_eeh_ioctl(tcegrp->grp,
1090 cmd, arg);
1091 if (ret)
1092 return ret;
1093 }
1094 return ret;
1095 }
1096
1097 case VFIO_IOMMU_SPAPR_TCE_CREATE: {
1098 struct vfio_iommu_spapr_tce_create create;
1099
1100 if (!container->v2)
1101 break;
1102
1103 ret = tce_iommu_mm_set(container);
1104 if (ret)
1105 return ret;
1106
1107 if (!tce_groups_attached(container))
1108 return -ENXIO;
1109
1110 minsz = offsetofend(struct vfio_iommu_spapr_tce_create,
1111 start_addr);
1112
1113 if (copy_from_user(&create, (void __user *)arg, minsz))
1114 return -EFAULT;
1115
1116 if (create.argsz < minsz)
1117 return -EINVAL;
1118
1119 if (create.flags)
1120 return -EINVAL;
1121
1122 mutex_lock(&container->lock);
1123
1124 ret = tce_iommu_create_default_window(container);
1125 if (!ret)
1126 ret = tce_iommu_create_window(container,
1127 create.page_shift,
1128 create.window_size, create.levels,
1129 &create.start_addr);
1130
1131 mutex_unlock(&container->lock);
1132
1133 if (!ret && copy_to_user((void __user *)arg, &create, minsz))
1134 ret = -EFAULT;
1135
1136 return ret;
1137 }
1138 case VFIO_IOMMU_SPAPR_TCE_REMOVE: {
1139 struct vfio_iommu_spapr_tce_remove remove;
1140
1141 if (!container->v2)
1142 break;
1143
1144 ret = tce_iommu_mm_set(container);
1145 if (ret)
1146 return ret;
1147
1148 if (!tce_groups_attached(container))
1149 return -ENXIO;
1150
1151 minsz = offsetofend(struct vfio_iommu_spapr_tce_remove,
1152 start_addr);
1153
1154 if (copy_from_user(&remove, (void __user *)arg, minsz))
1155 return -EFAULT;
1156
1157 if (remove.argsz < minsz)
1158 return -EINVAL;
1159
1160 if (remove.flags)
1161 return -EINVAL;
1162
1163 if (container->def_window_pending && !remove.start_addr) {
1164 container->def_window_pending = false;
1165 return 0;
1166 }
1167
1168 mutex_lock(&container->lock);
1169
1170 ret = tce_iommu_remove_window(container, remove.start_addr);
1171
1172 mutex_unlock(&container->lock);
1173
1174 return ret;
1175 }
1176 }
1177
1178 return -ENOTTY;
1179 }
1180
1181 static void tce_iommu_release_ownership(struct tce_container *container,
1182 struct iommu_table_group *table_group)
1183 {
1184 int i;
1185
1186 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) {
1187 struct iommu_table *tbl = container->tables[i];
1188
1189 if (!tbl)
1190 continue;
1191
1192 tce_iommu_clear(container, tbl, tbl->it_offset, tbl->it_size);
1193 if (tbl->it_map)
1194 iommu_release_ownership(tbl);
1195
1196 container->tables[i] = NULL;
1197 }
1198 }
1199
1200 static int tce_iommu_take_ownership(struct tce_container *container,
1201 struct iommu_table_group *table_group)
1202 {
1203 int i, j, rc = 0;
1204
1205 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) {
1206 struct iommu_table *tbl = table_group->tables[i];
1207
1208 if (!tbl || !tbl->it_map)
1209 continue;
1210
1211 rc = iommu_take_ownership(tbl);
1212 if (rc) {
1213 for (j = 0; j < i; ++j)
1214 iommu_release_ownership(
1215 table_group->tables[j]);
1216
1217 return rc;
1218 }
1219 }
1220
1221 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i)
1222 container->tables[i] = table_group->tables[i];
1223
1224 return 0;
1225 }
1226
1227 static void tce_iommu_release_ownership_ddw(struct tce_container *container,
1228 struct iommu_table_group *table_group)
1229 {
1230 long i;
1231
1232 if (!table_group->ops->unset_window) {
1233 WARN_ON_ONCE(1);
1234 return;
1235 }
1236
1237 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i)
1238 if (container->tables[i])
1239 table_group->ops->unset_window(table_group, i);
1240
1241 table_group->ops->release_ownership(table_group);
1242 }
1243
1244 static long tce_iommu_take_ownership_ddw(struct tce_container *container,
1245 struct iommu_table_group *table_group)
1246 {
1247 long i, ret = 0;
1248
1249 if (!table_group->ops->create_table || !table_group->ops->set_window ||
1250 !table_group->ops->release_ownership) {
1251 WARN_ON_ONCE(1);
1252 return -EFAULT;
1253 }
1254
1255 table_group->ops->take_ownership(table_group);
1256
1257 /* Set all windows to the new group */
1258 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) {
1259 struct iommu_table *tbl = container->tables[i];
1260
1261 if (!tbl)
1262 continue;
1263
1264 ret = table_group->ops->set_window(table_group, i, tbl);
1265 if (ret)
1266 goto release_exit;
1267 }
1268
1269 return 0;
1270
1271 release_exit:
1272 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i)
1273 table_group->ops->unset_window(table_group, i);
1274
1275 table_group->ops->release_ownership(table_group);
1276
1277 return ret;
1278 }
1279
1280 static int tce_iommu_attach_group(void *iommu_data,
1281 struct iommu_group *iommu_group)
1282 {
1283 int ret;
1284 struct tce_container *container = iommu_data;
1285 struct iommu_table_group *table_group;
1286 struct tce_iommu_group *tcegrp = NULL;
1287
1288 mutex_lock(&container->lock);
1289
1290 /* pr_debug("tce_vfio: Attaching group #%u to iommu %p\n",
1291 iommu_group_id(iommu_group), iommu_group); */
1292 table_group = iommu_group_get_iommudata(iommu_group);
1293 if (!table_group) {
1294 ret = -ENODEV;
1295 goto unlock_exit;
1296 }
1297
1298 if (tce_groups_attached(container) && (!table_group->ops ||
1299 !table_group->ops->take_ownership ||
1300 !table_group->ops->release_ownership)) {
1301 ret = -EBUSY;
1302 goto unlock_exit;
1303 }
1304
1305 /* Check if new group has the same iommu_ops (i.e. compatible) */
1306 list_for_each_entry(tcegrp, &container->group_list, next) {
1307 struct iommu_table_group *table_group_tmp;
1308
1309 if (tcegrp->grp == iommu_group) {
1310 pr_warn("tce_vfio: Group %d is already attached\n",
1311 iommu_group_id(iommu_group));
1312 ret = -EBUSY;
1313 goto unlock_exit;
1314 }
1315 table_group_tmp = iommu_group_get_iommudata(tcegrp->grp);
1316 if (table_group_tmp->ops->create_table !=
1317 table_group->ops->create_table) {
1318 pr_warn("tce_vfio: Group %d is incompatible with group %d\n",
1319 iommu_group_id(iommu_group),
1320 iommu_group_id(tcegrp->grp));
1321 ret = -EPERM;
1322 goto unlock_exit;
1323 }
1324 }
1325
1326 tcegrp = kzalloc(sizeof(*tcegrp), GFP_KERNEL);
1327 if (!tcegrp) {
1328 ret = -ENOMEM;
1329 goto unlock_exit;
1330 }
1331
1332 if (!table_group->ops || !table_group->ops->take_ownership ||
1333 !table_group->ops->release_ownership) {
1334 if (container->v2) {
1335 ret = -EPERM;
1336 goto unlock_exit;
1337 }
1338 ret = tce_iommu_take_ownership(container, table_group);
1339 } else {
1340 if (!container->v2) {
1341 ret = -EPERM;
1342 goto unlock_exit;
1343 }
1344 ret = tce_iommu_take_ownership_ddw(container, table_group);
1345 if (!tce_groups_attached(container) && !container->tables[0])
1346 container->def_window_pending = true;
1347 }
1348
1349 if (!ret) {
1350 tcegrp->grp = iommu_group;
1351 list_add(&tcegrp->next, &container->group_list);
1352 }
1353
1354 unlock_exit:
1355 if (ret && tcegrp)
1356 kfree(tcegrp);
1357
1358 mutex_unlock(&container->lock);
1359
1360 return ret;
1361 }
1362
1363 static void tce_iommu_detach_group(void *iommu_data,
1364 struct iommu_group *iommu_group)
1365 {
1366 struct tce_container *container = iommu_data;
1367 struct iommu_table_group *table_group;
1368 bool found = false;
1369 struct tce_iommu_group *tcegrp;
1370
1371 mutex_lock(&container->lock);
1372
1373 list_for_each_entry(tcegrp, &container->group_list, next) {
1374 if (tcegrp->grp == iommu_group) {
1375 found = true;
1376 break;
1377 }
1378 }
1379
1380 if (!found) {
1381 pr_warn("tce_vfio: detaching unattached group #%u\n",
1382 iommu_group_id(iommu_group));
1383 goto unlock_exit;
1384 }
1385
1386 list_del(&tcegrp->next);
1387 kfree(tcegrp);
1388
1389 table_group = iommu_group_get_iommudata(iommu_group);
1390 BUG_ON(!table_group);
1391
1392 if (!table_group->ops || !table_group->ops->release_ownership)
1393 tce_iommu_release_ownership(container, table_group);
1394 else
1395 tce_iommu_release_ownership_ddw(container, table_group);
1396
1397 unlock_exit:
1398 mutex_unlock(&container->lock);
1399 }
1400
1401 static const struct vfio_iommu_driver_ops tce_iommu_driver_ops = {
1402 .name = "iommu-vfio-powerpc",
1403 .owner = THIS_MODULE,
1404 .open = tce_iommu_open,
1405 .release = tce_iommu_release,
1406 .ioctl = tce_iommu_ioctl,
1407 .attach_group = tce_iommu_attach_group,
1408 .detach_group = tce_iommu_detach_group,
1409 };
1410
1411 static int __init tce_iommu_init(void)
1412 {
1413 return vfio_register_iommu_driver(&tce_iommu_driver_ops);
1414 }
1415
1416 static void __exit tce_iommu_cleanup(void)
1417 {
1418 vfio_unregister_iommu_driver(&tce_iommu_driver_ops);
1419 }
1420
1421 module_init(tce_iommu_init);
1422 module_exit(tce_iommu_cleanup);
1423
1424 MODULE_VERSION(DRIVER_VERSION);
1425 MODULE_LICENSE("GPL v2");
1426 MODULE_AUTHOR(DRIVER_AUTHOR);
1427 MODULE_DESCRIPTION(DRIVER_DESC);
1428
Mirror https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git