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btrfs: scrub: use GFP_KERNEL on the submission path
[linux-2.6/btrfs-unstable.git] / drivers / vfio / vfio_iommu_spapr_tce.c
blob0582b72ef3772cf1257cc330dcf5e32246fe72bb
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 <asm/iommu.h>
24 #include <asm/tce.h>
25 #include <asm/mmu_context.h>
26
27 #define DRIVER_VERSION "0.1"
28 #define DRIVER_AUTHOR "aik@ozlabs.ru"
29 #define DRIVER_DESC "VFIO IOMMU SPAPR TCE"
30
31 static void tce_iommu_detach_group(void *iommu_data,
32 struct iommu_group *iommu_group);
33
34 static long try_increment_locked_vm(long npages)
35 {
36 long ret = 0, locked, lock_limit;
37
38 if (!current || !current->mm)
39 return -ESRCH; /* process exited */
40
41 if (!npages)
42 return 0;
43
44 down_write(&current->mm->mmap_sem);
45 locked = current->mm->locked_vm + npages;
46 lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
47 if (locked > lock_limit && !capable(CAP_IPC_LOCK))
48 ret = -ENOMEM;
49 else
50 current->mm->locked_vm += npages;
51
52 pr_debug("[%d] RLIMIT_MEMLOCK +%ld %ld/%ld%s\n", current->pid,
53 npages << PAGE_SHIFT,
54 current->mm->locked_vm << PAGE_SHIFT,
55 rlimit(RLIMIT_MEMLOCK),
56 ret ? " - exceeded" : "");
57
58 up_write(&current->mm->mmap_sem);
59
60 return ret;
61 }
62
63 static void decrement_locked_vm(long npages)
64 {
65 if (!current || !current->mm || !npages)
66 return; /* process exited */
67
68 down_write(&current->mm->mmap_sem);
69 if (WARN_ON_ONCE(npages > current->mm->locked_vm))
70 npages = current->mm->locked_vm;
71 current->mm->locked_vm -= npages;
72 pr_debug("[%d] RLIMIT_MEMLOCK -%ld %ld/%ld\n", current->pid,
73 npages << PAGE_SHIFT,
74 current->mm->locked_vm << PAGE_SHIFT,
75 rlimit(RLIMIT_MEMLOCK));
76 up_write(&current->mm->mmap_sem);
77 }
78
79 /*
80 * VFIO IOMMU fd for SPAPR_TCE IOMMU implementation
81 *
82 * This code handles mapping and unmapping of user data buffers
83 * into DMA'ble space using the IOMMU
84 */
85
86 struct tce_iommu_group {
87 struct list_head next;
88 struct iommu_group *grp;
89 };
90
91 /*
92 * The container descriptor supports only a single group per container.
93 * Required by the API as the container is not supplied with the IOMMU group
94 * at the moment of initialization.
95 */
96 struct tce_container {
97 struct mutex lock;
98 bool enabled;
99 bool v2;
100 unsigned long locked_pages;
101 struct iommu_table *tables[IOMMU_TABLE_GROUP_MAX_TABLES];
102 struct list_head group_list;
103 };
104
105 static long tce_iommu_unregister_pages(struct tce_container *container,
106 __u64 vaddr, __u64 size)
107 {
108 struct mm_iommu_table_group_mem_t *mem;
109
110 if ((vaddr & ~PAGE_MASK) || (size & ~PAGE_MASK))
111 return -EINVAL;
112
113 mem = mm_iommu_find(vaddr, size >> PAGE_SHIFT);
114 if (!mem)
115 return -ENOENT;
116
117 return mm_iommu_put(mem);
118 }
119
120 static long tce_iommu_register_pages(struct tce_container *container,
121 __u64 vaddr, __u64 size)
122 {
123 long ret = 0;
124 struct mm_iommu_table_group_mem_t *mem = NULL;
125 unsigned long entries = size >> PAGE_SHIFT;
126
127 if ((vaddr & ~PAGE_MASK) || (size & ~PAGE_MASK) ||
128 ((vaddr + size) < vaddr))
129 return -EINVAL;
130
131 ret = mm_iommu_get(vaddr, entries, &mem);
132 if (ret)
133 return ret;
134
135 container->enabled = true;
136
137 return 0;
138 }
139
140 static long tce_iommu_userspace_view_alloc(struct iommu_table *tbl)
141 {
142 unsigned long cb = _ALIGN_UP(sizeof(tbl->it_userspace[0]) *
143 tbl->it_size, PAGE_SIZE);
144 unsigned long *uas;
145 long ret;
146
147 BUG_ON(tbl->it_userspace);
148
149 ret = try_increment_locked_vm(cb >> PAGE_SHIFT);
150 if (ret)
151 return ret;
152
153 uas = vzalloc(cb);
154 if (!uas) {
155 decrement_locked_vm(cb >> PAGE_SHIFT);
156 return -ENOMEM;
157 }
158 tbl->it_userspace = uas;
159
160 return 0;
161 }
162
163 static void tce_iommu_userspace_view_free(struct iommu_table *tbl)
164 {
165 unsigned long cb = _ALIGN_UP(sizeof(tbl->it_userspace[0]) *
166 tbl->it_size, PAGE_SIZE);
167
168 if (!tbl->it_userspace)
169 return;
170
171 vfree(tbl->it_userspace);
172 tbl->it_userspace = NULL;
173 decrement_locked_vm(cb >> PAGE_SHIFT);
174 }
175
176 static bool tce_page_is_contained(struct page *page, unsigned page_shift)
177 {
178 /*
179 * Check that the TCE table granularity is not bigger than the size of
180 * a page we just found. Otherwise the hardware can get access to
181 * a bigger memory chunk that it should.
182 */
183 return (PAGE_SHIFT + compound_order(compound_head(page))) >= page_shift;
184 }
185
186 static inline bool tce_groups_attached(struct tce_container *container)
187 {
188 return !list_empty(&container->group_list);
189 }
190
191 static long tce_iommu_find_table(struct tce_container *container,
192 phys_addr_t ioba, struct iommu_table **ptbl)
193 {
194 long i;
195
196 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) {
197 struct iommu_table *tbl = container->tables[i];
198
199 if (tbl) {
200 unsigned long entry = ioba >> tbl->it_page_shift;
201 unsigned long start = tbl->it_offset;
202 unsigned long end = start + tbl->it_size;
203
204 if ((start <= entry) && (entry < end)) {
205 *ptbl = tbl;
206 return i;
207 }
208 }
209 }
210
211 return -1;
212 }
213
214 static int tce_iommu_find_free_table(struct tce_container *container)
215 {
216 int i;
217
218 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) {
219 if (!container->tables[i])
220 return i;
221 }
222
223 return -ENOSPC;
224 }
225
226 static int tce_iommu_enable(struct tce_container *container)
227 {
228 int ret = 0;
229 unsigned long locked;
230 struct iommu_table_group *table_group;
231 struct tce_iommu_group *tcegrp;
232
233 if (!current->mm)
234 return -ESRCH; /* process exited */
235
236 if (container->enabled)
237 return -EBUSY;
238
239 /*
240 * When userspace pages are mapped into the IOMMU, they are effectively
241 * locked memory, so, theoretically, we need to update the accounting
242 * of locked pages on each map and unmap. For powerpc, the map unmap
243 * paths can be very hot, though, and the accounting would kill
244 * performance, especially since it would be difficult to impossible
245 * to handle the accounting in real mode only.
246 *
247 * To address that, rather than precisely accounting every page, we
248 * instead account for a worst case on locked memory when the iommu is
249 * enabled and disabled. The worst case upper bound on locked memory
250 * is the size of the whole iommu window, which is usually relatively
251 * small (compared to total memory sizes) on POWER hardware.
252 *
253 * Also we don't have a nice way to fail on H_PUT_TCE due to ulimits,
254 * that would effectively kill the guest at random points, much better
255 * enforcing the limit based on the max that the guest can map.
256 *
257 * Unfortunately at the moment it counts whole tables, no matter how
258 * much memory the guest has. I.e. for 4GB guest and 4 IOMMU groups
259 * each with 2GB DMA window, 8GB will be counted here. The reason for
260 * this is that we cannot tell here the amount of RAM used by the guest
261 * as this information is only available from KVM and VFIO is
262 * KVM agnostic.
263 *
264 * So we do not allow enabling a container without a group attached
265 * as there is no way to know how much we should increment
266 * the locked_vm counter.
267 */
268 if (!tce_groups_attached(container))
269 return -ENODEV;
270
271 tcegrp = list_first_entry(&container->group_list,
272 struct tce_iommu_group, next);
273 table_group = iommu_group_get_iommudata(tcegrp->grp);
274 if (!table_group)
275 return -ENODEV;
276
277 if (!table_group->tce32_size)
278 return -EPERM;
279
280 locked = table_group->tce32_size >> PAGE_SHIFT;
281 ret = try_increment_locked_vm(locked);
282 if (ret)
283 return ret;
284
285 container->locked_pages = locked;
286
287 container->enabled = true;
288
289 return ret;
290 }
291
292 static void tce_iommu_disable(struct tce_container *container)
293 {
294 if (!container->enabled)
295 return;
296
297 container->enabled = false;
298
299 if (!current->mm)
300 return;
301
302 decrement_locked_vm(container->locked_pages);
303 }
304
305 static void *tce_iommu_open(unsigned long arg)
306 {
307 struct tce_container *container;
308
309 if ((arg != VFIO_SPAPR_TCE_IOMMU) && (arg != VFIO_SPAPR_TCE_v2_IOMMU)) {
310 pr_err("tce_vfio: Wrong IOMMU type\n");
311 return ERR_PTR(-EINVAL);
312 }
313
314 container = kzalloc(sizeof(*container), GFP_KERNEL);
315 if (!container)
316 return ERR_PTR(-ENOMEM);
317
318 mutex_init(&container->lock);
319 INIT_LIST_HEAD_RCU(&container->group_list);
320
321 container->v2 = arg == VFIO_SPAPR_TCE_v2_IOMMU;
322
323 return container;
324 }
325
326 static int tce_iommu_clear(struct tce_container *container,
327 struct iommu_table *tbl,
328 unsigned long entry, unsigned long pages);
329 static void tce_iommu_free_table(struct iommu_table *tbl);
330
331 static void tce_iommu_release(void *iommu_data)
332 {
333 struct tce_container *container = iommu_data;
334 struct iommu_table_group *table_group;
335 struct tce_iommu_group *tcegrp;
336 long i;
337
338 while (tce_groups_attached(container)) {
339 tcegrp = list_first_entry(&container->group_list,
340 struct tce_iommu_group, next);
341 table_group = iommu_group_get_iommudata(tcegrp->grp);
342 tce_iommu_detach_group(iommu_data, tcegrp->grp);
343 }
344
345 /*
346 * If VFIO created a table, it was not disposed
347 * by tce_iommu_detach_group() so do it now.
348 */
349 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) {
350 struct iommu_table *tbl = container->tables[i];
351
352 if (!tbl)
353 continue;
354
355 tce_iommu_clear(container, tbl, tbl->it_offset, tbl->it_size);
356 tce_iommu_free_table(tbl);
357 }
358
359 tce_iommu_disable(container);
360 mutex_destroy(&container->lock);
361
362 kfree(container);
363 }
364
365 static void tce_iommu_unuse_page(struct tce_container *container,
366 unsigned long hpa)
367 {
368 struct page *page;
369
370 page = pfn_to_page(hpa >> PAGE_SHIFT);
371 put_page(page);
372 }
373
374 static int tce_iommu_prereg_ua_to_hpa(unsigned long tce, unsigned long size,
375 unsigned long *phpa, struct mm_iommu_table_group_mem_t **pmem)
376 {
377 long ret = 0;
378 struct mm_iommu_table_group_mem_t *mem;
379
380 mem = mm_iommu_lookup(tce, size);
381 if (!mem)
382 return -EINVAL;
383
384 ret = mm_iommu_ua_to_hpa(mem, tce, phpa);
385 if (ret)
386 return -EINVAL;
387
388 *pmem = mem;
389
390 return 0;
391 }
392
393 static void tce_iommu_unuse_page_v2(struct iommu_table *tbl,
394 unsigned long entry)
395 {
396 struct mm_iommu_table_group_mem_t *mem = NULL;
397 int ret;
398 unsigned long hpa = 0;
399 unsigned long *pua = IOMMU_TABLE_USERSPACE_ENTRY(tbl, entry);
400
401 if (!pua || !current || !current->mm)
402 return;
403
404 ret = tce_iommu_prereg_ua_to_hpa(*pua, IOMMU_PAGE_SIZE(tbl),
405 &hpa, &mem);
406 if (ret)
407 pr_debug("%s: tce %lx at #%lx was not cached, ret=%d\n",
408 __func__, *pua, entry, ret);
409 if (mem)
410 mm_iommu_mapped_dec(mem);
411
412 *pua = 0;
413 }
414
415 static int tce_iommu_clear(struct tce_container *container,
416 struct iommu_table *tbl,
417 unsigned long entry, unsigned long pages)
418 {
419 unsigned long oldhpa;
420 long ret;
421 enum dma_data_direction direction;
422
423 for ( ; pages; --pages, ++entry) {
424 direction = DMA_NONE;
425 oldhpa = 0;
426 ret = iommu_tce_xchg(tbl, entry, &oldhpa, &direction);
427 if (ret)
428 continue;
429
430 if (direction == DMA_NONE)
431 continue;
432
433 if (container->v2) {
434 tce_iommu_unuse_page_v2(tbl, entry);
435 continue;
436 }
437
438 tce_iommu_unuse_page(container, oldhpa);
439 }
440
441 return 0;
442 }
443
444 static int tce_iommu_use_page(unsigned long tce, unsigned long *hpa)
445 {
446 struct page *page = NULL;
447 enum dma_data_direction direction = iommu_tce_direction(tce);
448
449 if (get_user_pages_fast(tce & PAGE_MASK, 1,
450 direction != DMA_TO_DEVICE, &page) != 1)
451 return -EFAULT;
452
453 *hpa = __pa((unsigned long) page_address(page));
454
455 return 0;
456 }
457
458 static long tce_iommu_build(struct tce_container *container,
459 struct iommu_table *tbl,
460 unsigned long entry, unsigned long tce, unsigned long pages,
461 enum dma_data_direction direction)
462 {
463 long i, ret = 0;
464 struct page *page;
465 unsigned long hpa;
466 enum dma_data_direction dirtmp;
467
468 for (i = 0; i < pages; ++i) {
469 unsigned long offset = tce & IOMMU_PAGE_MASK(tbl) & ~PAGE_MASK;
470
471 ret = tce_iommu_use_page(tce, &hpa);
472 if (ret)
473 break;
474
475 page = pfn_to_page(hpa >> PAGE_SHIFT);
476 if (!tce_page_is_contained(page, tbl->it_page_shift)) {
477 ret = -EPERM;
478 break;
479 }
480
481 hpa |= offset;
482 dirtmp = direction;
483 ret = iommu_tce_xchg(tbl, entry + i, &hpa, &dirtmp);
484 if (ret) {
485 tce_iommu_unuse_page(container, hpa);
486 pr_err("iommu_tce: %s failed ioba=%lx, tce=%lx, ret=%ld\n",
487 __func__, entry << tbl->it_page_shift,
488 tce, ret);
489 break;
490 }
491
492 if (dirtmp != DMA_NONE)
493 tce_iommu_unuse_page(container, hpa);
494
495 tce += IOMMU_PAGE_SIZE(tbl);
496 }
497
498 if (ret)
499 tce_iommu_clear(container, tbl, entry, i);
500
501 return ret;
502 }
503
504 static long tce_iommu_build_v2(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 struct mm_iommu_table_group_mem_t *mem = NULL;
516 unsigned long *pua = IOMMU_TABLE_USERSPACE_ENTRY(tbl,
517 entry + i);
518
519 ret = tce_iommu_prereg_ua_to_hpa(tce, IOMMU_PAGE_SIZE(tbl),
520 &hpa, &mem);
521 if (ret)
522 break;
523
524 page = pfn_to_page(hpa >> PAGE_SHIFT);
525 if (!tce_page_is_contained(page, tbl->it_page_shift)) {
526 ret = -EPERM;
527 break;
528 }
529
530 /* Preserve offset within IOMMU page */
531 hpa |= tce & IOMMU_PAGE_MASK(tbl) & ~PAGE_MASK;
532 dirtmp = direction;
533
534 /* The registered region is being unregistered */
535 if (mm_iommu_mapped_inc(mem))
536 break;
537
538 ret = iommu_tce_xchg(tbl, entry + i, &hpa, &dirtmp);
539 if (ret) {
540 /* dirtmp cannot be DMA_NONE here */
541 tce_iommu_unuse_page_v2(tbl, entry + i);
542 pr_err("iommu_tce: %s failed ioba=%lx, tce=%lx, ret=%ld\n",
543 __func__, entry << tbl->it_page_shift,
544 tce, ret);
545 break;
546 }
547
548 if (dirtmp != DMA_NONE)
549 tce_iommu_unuse_page_v2(tbl, entry + i);
550
551 *pua = tce;
552
553 tce += IOMMU_PAGE_SIZE(tbl);
554 }
555
556 if (ret)
557 tce_iommu_clear(container, tbl, entry, i);
558
559 return ret;
560 }
561
562 static long tce_iommu_create_table(struct tce_container *container,
563 struct iommu_table_group *table_group,
564 int num,
565 __u32 page_shift,
566 __u64 window_size,
567 __u32 levels,
568 struct iommu_table **ptbl)
569 {
570 long ret, table_size;
571
572 table_size = table_group->ops->get_table_size(page_shift, window_size,
573 levels);
574 if (!table_size)
575 return -EINVAL;
576
577 ret = try_increment_locked_vm(table_size >> PAGE_SHIFT);
578 if (ret)
579 return ret;
580
581 ret = table_group->ops->create_table(table_group, num,
582 page_shift, window_size, levels, ptbl);
583
584 WARN_ON(!ret && !(*ptbl)->it_ops->free);
585 WARN_ON(!ret && ((*ptbl)->it_allocated_size != table_size));
586
587 if (!ret && container->v2) {
588 ret = tce_iommu_userspace_view_alloc(*ptbl);
589 if (ret)
590 (*ptbl)->it_ops->free(*ptbl);
591 }
592
593 if (ret)
594 decrement_locked_vm(table_size >> PAGE_SHIFT);
595
596 return ret;
597 }
598
599 static void tce_iommu_free_table(struct iommu_table *tbl)
600 {
601 unsigned long pages = tbl->it_allocated_size >> PAGE_SHIFT;
602
603 tce_iommu_userspace_view_free(tbl);
604 tbl->it_ops->free(tbl);
605 decrement_locked_vm(pages);
606 }
607
608 static long tce_iommu_create_window(struct tce_container *container,
609 __u32 page_shift, __u64 window_size, __u32 levels,
610 __u64 *start_addr)
611 {
612 struct tce_iommu_group *tcegrp;
613 struct iommu_table_group *table_group;
614 struct iommu_table *tbl = NULL;
615 long ret, num;
616
617 num = tce_iommu_find_free_table(container);
618 if (num < 0)
619 return num;
620
621 /* Get the first group for ops::create_table */
622 tcegrp = list_first_entry(&container->group_list,
623 struct tce_iommu_group, next);
624 table_group = iommu_group_get_iommudata(tcegrp->grp);
625 if (!table_group)
626 return -EFAULT;
627
628 if (!(table_group->pgsizes & (1ULL << page_shift)))
629 return -EINVAL;
630
631 if (!table_group->ops->set_window || !table_group->ops->unset_window ||
632 !table_group->ops->get_table_size ||
633 !table_group->ops->create_table)
634 return -EPERM;
635
636 /* Create TCE table */
637 ret = tce_iommu_create_table(container, table_group, num,
638 page_shift, window_size, levels, &tbl);
639 if (ret)
640 return ret;
641
642 BUG_ON(!tbl->it_ops->free);
643
644 /*
645 * Program the table to every group.
646 * Groups have been tested for compatibility at the attach time.
647 */
648 list_for_each_entry(tcegrp, &container->group_list, next) {
649 table_group = iommu_group_get_iommudata(tcegrp->grp);
650
651 ret = table_group->ops->set_window(table_group, num, tbl);
652 if (ret)
653 goto unset_exit;
654 }
655
656 container->tables[num] = tbl;
657
658 /* Return start address assigned by platform in create_table() */
659 *start_addr = tbl->it_offset << tbl->it_page_shift;
660
661 return 0;
662
663 unset_exit:
664 list_for_each_entry(tcegrp, &container->group_list, next) {
665 table_group = iommu_group_get_iommudata(tcegrp->grp);
666 table_group->ops->unset_window(table_group, num);
667 }
668 tce_iommu_free_table(tbl);
669
670 return ret;
671 }
672
673 static long tce_iommu_remove_window(struct tce_container *container,
674 __u64 start_addr)
675 {
676 struct iommu_table_group *table_group = NULL;
677 struct iommu_table *tbl;
678 struct tce_iommu_group *tcegrp;
679 int num;
680
681 num = tce_iommu_find_table(container, start_addr, &tbl);
682 if (num < 0)
683 return -EINVAL;
684
685 BUG_ON(!tbl->it_size);
686
687 /* Detach groups from IOMMUs */
688 list_for_each_entry(tcegrp, &container->group_list, next) {
689 table_group = iommu_group_get_iommudata(tcegrp->grp);
690
691 /*
692 * SPAPR TCE IOMMU exposes the default DMA window to
693 * the guest via dma32_window_start/size of
694 * VFIO_IOMMU_SPAPR_TCE_GET_INFO. Some platforms allow
695 * the userspace to remove this window, some do not so
696 * here we check for the platform capability.
697 */
698 if (!table_group->ops || !table_group->ops->unset_window)
699 return -EPERM;
700
701 table_group->ops->unset_window(table_group, num);
702 }
703
704 /* Free table */
705 tce_iommu_clear(container, tbl, tbl->it_offset, tbl->it_size);
706 tce_iommu_free_table(tbl);
707 container->tables[num] = NULL;
708
709 return 0;
710 }
711
712 static long tce_iommu_ioctl(void *iommu_data,
713 unsigned int cmd, unsigned long arg)
714 {
715 struct tce_container *container = iommu_data;
716 unsigned long minsz, ddwsz;
717 long ret;
718
719 switch (cmd) {
720 case VFIO_CHECK_EXTENSION:
721 switch (arg) {
722 case VFIO_SPAPR_TCE_IOMMU:
723 case VFIO_SPAPR_TCE_v2_IOMMU:
724 ret = 1;
725 break;
726 default:
727 ret = vfio_spapr_iommu_eeh_ioctl(NULL, cmd, arg);
728 break;
729 }
730
731 return (ret < 0) ? 0 : ret;
732
733 case VFIO_IOMMU_SPAPR_TCE_GET_INFO: {
734 struct vfio_iommu_spapr_tce_info info;
735 struct tce_iommu_group *tcegrp;
736 struct iommu_table_group *table_group;
737
738 if (!tce_groups_attached(container))
739 return -ENXIO;
740
741 tcegrp = list_first_entry(&container->group_list,
742 struct tce_iommu_group, next);
743 table_group = iommu_group_get_iommudata(tcegrp->grp);
744
745 if (!table_group)
746 return -ENXIO;
747
748 minsz = offsetofend(struct vfio_iommu_spapr_tce_info,
749 dma32_window_size);
750
751 if (copy_from_user(&info, (void __user *)arg, minsz))
752 return -EFAULT;
753
754 if (info.argsz < minsz)
755 return -EINVAL;
756
757 info.dma32_window_start = table_group->tce32_start;
758 info.dma32_window_size = table_group->tce32_size;
759 info.flags = 0;
760 memset(&info.ddw, 0, sizeof(info.ddw));
761
762 if (table_group->max_dynamic_windows_supported &&
763 container->v2) {
764 info.flags |= VFIO_IOMMU_SPAPR_INFO_DDW;
765 info.ddw.pgsizes = table_group->pgsizes;
766 info.ddw.max_dynamic_windows_supported =
767 table_group->max_dynamic_windows_supported;
768 info.ddw.levels = table_group->max_levels;
769 }
770
771 ddwsz = offsetofend(struct vfio_iommu_spapr_tce_info, ddw);
772
773 if (info.argsz >= ddwsz)
774 minsz = ddwsz;
775
776 if (copy_to_user((void __user *)arg, &info, minsz))
777 return -EFAULT;
778
779 return 0;
780 }
781 case VFIO_IOMMU_MAP_DMA: {
782 struct vfio_iommu_type1_dma_map param;
783 struct iommu_table *tbl = NULL;
784 long num;
785 enum dma_data_direction direction;
786
787 if (!container->enabled)
788 return -EPERM;
789
790 minsz = offsetofend(struct vfio_iommu_type1_dma_map, size);
791
792 if (copy_from_user(&param, (void __user *)arg, minsz))
793 return -EFAULT;
794
795 if (param.argsz < minsz)
796 return -EINVAL;
797
798 if (param.flags & ~(VFIO_DMA_MAP_FLAG_READ |
799 VFIO_DMA_MAP_FLAG_WRITE))
800 return -EINVAL;
801
802 num = tce_iommu_find_table(container, param.iova, &tbl);
803 if (num < 0)
804 return -ENXIO;
805
806 if ((param.size & ~IOMMU_PAGE_MASK(tbl)) ||
807 (param.vaddr & ~IOMMU_PAGE_MASK(tbl)))
808 return -EINVAL;
809
810 /* iova is checked by the IOMMU API */
811 if (param.flags & VFIO_DMA_MAP_FLAG_READ) {
812 if (param.flags & VFIO_DMA_MAP_FLAG_WRITE)
813 direction = DMA_BIDIRECTIONAL;
814 else
815 direction = DMA_TO_DEVICE;
816 } else {
817 if (param.flags & VFIO_DMA_MAP_FLAG_WRITE)
818 direction = DMA_FROM_DEVICE;
819 else
820 return -EINVAL;
821 }
822
823 ret = iommu_tce_put_param_check(tbl, param.iova, param.vaddr);
824 if (ret)
825 return ret;
826
827 if (container->v2)
828 ret = tce_iommu_build_v2(container, tbl,
829 param.iova >> tbl->it_page_shift,
830 param.vaddr,
831 param.size >> tbl->it_page_shift,
832 direction);
833 else
834 ret = tce_iommu_build(container, tbl,
835 param.iova >> tbl->it_page_shift,
836 param.vaddr,
837 param.size >> tbl->it_page_shift,
838 direction);
839
840 iommu_flush_tce(tbl);
841
842 return ret;
843 }
844 case VFIO_IOMMU_UNMAP_DMA: {
845 struct vfio_iommu_type1_dma_unmap param;
846 struct iommu_table *tbl = NULL;
847 long num;
848
849 if (!container->enabled)
850 return -EPERM;
851
852 minsz = offsetofend(struct vfio_iommu_type1_dma_unmap,
853 size);
854
855 if (copy_from_user(&param, (void __user *)arg, minsz))
856 return -EFAULT;
857
858 if (param.argsz < minsz)
859 return -EINVAL;
860
861 /* No flag is supported now */
862 if (param.flags)
863 return -EINVAL;
864
865 num = tce_iommu_find_table(container, param.iova, &tbl);
866 if (num < 0)
867 return -ENXIO;
868
869 if (param.size & ~IOMMU_PAGE_MASK(tbl))
870 return -EINVAL;
871
872 ret = iommu_tce_clear_param_check(tbl, param.iova, 0,
873 param.size >> tbl->it_page_shift);
874 if (ret)
875 return ret;
876
877 ret = tce_iommu_clear(container, tbl,
878 param.iova >> tbl->it_page_shift,
879 param.size >> tbl->it_page_shift);
880 iommu_flush_tce(tbl);
881
882 return ret;
883 }
884 case VFIO_IOMMU_SPAPR_REGISTER_MEMORY: {
885 struct vfio_iommu_spapr_register_memory param;
886
887 if (!container->v2)
888 break;
889
890 minsz = offsetofend(struct vfio_iommu_spapr_register_memory,
891 size);
892
893 if (copy_from_user(&param, (void __user *)arg, minsz))
894 return -EFAULT;
895
896 if (param.argsz < minsz)
897 return -EINVAL;
898
899 /* No flag is supported now */
900 if (param.flags)
901 return -EINVAL;
902
903 mutex_lock(&container->lock);
904 ret = tce_iommu_register_pages(container, param.vaddr,
905 param.size);
906 mutex_unlock(&container->lock);
907
908 return ret;
909 }
910 case VFIO_IOMMU_SPAPR_UNREGISTER_MEMORY: {
911 struct vfio_iommu_spapr_register_memory param;
912
913 if (!container->v2)
914 break;
915
916 minsz = offsetofend(struct vfio_iommu_spapr_register_memory,
917 size);
918
919 if (copy_from_user(&param, (void __user *)arg, minsz))
920 return -EFAULT;
921
922 if (param.argsz < minsz)
923 return -EINVAL;
924
925 /* No flag is supported now */
926 if (param.flags)
927 return -EINVAL;
928
929 mutex_lock(&container->lock);
930 ret = tce_iommu_unregister_pages(container, param.vaddr,
931 param.size);
932 mutex_unlock(&container->lock);
933
934 return ret;
935 }
936 case VFIO_IOMMU_ENABLE:
937 if (container->v2)
938 break;
939
940 mutex_lock(&container->lock);
941 ret = tce_iommu_enable(container);
942 mutex_unlock(&container->lock);
943 return ret;
944
945
946 case VFIO_IOMMU_DISABLE:
947 if (container->v2)
948 break;
949
950 mutex_lock(&container->lock);
951 tce_iommu_disable(container);
952 mutex_unlock(&container->lock);
953 return 0;
954
955 case VFIO_EEH_PE_OP: {
956 struct tce_iommu_group *tcegrp;
957
958 ret = 0;
959 list_for_each_entry(tcegrp, &container->group_list, next) {
960 ret = vfio_spapr_iommu_eeh_ioctl(tcegrp->grp,
961 cmd, arg);
962 if (ret)
963 return ret;
964 }
965 return ret;
966 }
967
968 case VFIO_IOMMU_SPAPR_TCE_CREATE: {
969 struct vfio_iommu_spapr_tce_create create;
970
971 if (!container->v2)
972 break;
973
974 if (!tce_groups_attached(container))
975 return -ENXIO;
976
977 minsz = offsetofend(struct vfio_iommu_spapr_tce_create,
978 start_addr);
979
980 if (copy_from_user(&create, (void __user *)arg, minsz))
981 return -EFAULT;
982
983 if (create.argsz < minsz)
984 return -EINVAL;
985
986 if (create.flags)
987 return -EINVAL;
988
989 mutex_lock(&container->lock);
990
991 ret = tce_iommu_create_window(container, create.page_shift,
992 create.window_size, create.levels,
993 &create.start_addr);
994
995 mutex_unlock(&container->lock);
996
997 if (!ret && copy_to_user((void __user *)arg, &create, minsz))
998 ret = -EFAULT;
999
1000 return ret;
1001 }
1002 case VFIO_IOMMU_SPAPR_TCE_REMOVE: {
1003 struct vfio_iommu_spapr_tce_remove remove;
1004
1005 if (!container->v2)
1006 break;
1007
1008 if (!tce_groups_attached(container))
1009 return -ENXIO;
1010
1011 minsz = offsetofend(struct vfio_iommu_spapr_tce_remove,
1012 start_addr);
1013
1014 if (copy_from_user(&remove, (void __user *)arg, minsz))
1015 return -EFAULT;
1016
1017 if (remove.argsz < minsz)
1018 return -EINVAL;
1019
1020 if (remove.flags)
1021 return -EINVAL;
1022
1023 mutex_lock(&container->lock);
1024
1025 ret = tce_iommu_remove_window(container, remove.start_addr);
1026
1027 mutex_unlock(&container->lock);
1028
1029 return ret;
1030 }
1031 }
1032
1033 return -ENOTTY;
1034 }
1035
1036 static void tce_iommu_release_ownership(struct tce_container *container,
1037 struct iommu_table_group *table_group)
1038 {
1039 int i;
1040
1041 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) {
1042 struct iommu_table *tbl = container->tables[i];
1043
1044 if (!tbl)
1045 continue;
1046
1047 tce_iommu_clear(container, tbl, tbl->it_offset, tbl->it_size);
1048 tce_iommu_userspace_view_free(tbl);
1049 if (tbl->it_map)
1050 iommu_release_ownership(tbl);
1051
1052 container->tables[i] = NULL;
1053 }
1054 }
1055
1056 static int tce_iommu_take_ownership(struct tce_container *container,
1057 struct iommu_table_group *table_group)
1058 {
1059 int i, j, rc = 0;
1060
1061 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) {
1062 struct iommu_table *tbl = table_group->tables[i];
1063
1064 if (!tbl || !tbl->it_map)
1065 continue;
1066
1067 rc = tce_iommu_userspace_view_alloc(tbl);
1068 if (!rc)
1069 rc = iommu_take_ownership(tbl);
1070
1071 if (rc) {
1072 for (j = 0; j < i; ++j)
1073 iommu_release_ownership(
1074 table_group->tables[j]);
1075
1076 return rc;
1077 }
1078 }
1079
1080 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i)
1081 container->tables[i] = table_group->tables[i];
1082
1083 return 0;
1084 }
1085
1086 static void tce_iommu_release_ownership_ddw(struct tce_container *container,
1087 struct iommu_table_group *table_group)
1088 {
1089 long i;
1090
1091 if (!table_group->ops->unset_window) {
1092 WARN_ON_ONCE(1);
1093 return;
1094 }
1095
1096 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i)
1097 table_group->ops->unset_window(table_group, i);
1098
1099 table_group->ops->release_ownership(table_group);
1100 }
1101
1102 static long tce_iommu_take_ownership_ddw(struct tce_container *container,
1103 struct iommu_table_group *table_group)
1104 {
1105 long i, ret = 0;
1106 struct iommu_table *tbl = NULL;
1107
1108 if (!table_group->ops->create_table || !table_group->ops->set_window ||
1109 !table_group->ops->release_ownership) {
1110 WARN_ON_ONCE(1);
1111 return -EFAULT;
1112 }
1113
1114 table_group->ops->take_ownership(table_group);
1115
1116 /*
1117 * If it the first group attached, check if there is
1118 * a default DMA window and create one if none as
1119 * the userspace expects it to exist.
1120 */
1121 if (!tce_groups_attached(container) && !container->tables[0]) {
1122 ret = tce_iommu_create_table(container,
1123 table_group,
1124 0, /* window number */
1125 IOMMU_PAGE_SHIFT_4K,
1126 table_group->tce32_size,
1127 1, /* default levels */
1128 &tbl);
1129 if (ret)
1130 goto release_exit;
1131 else
1132 container->tables[0] = tbl;
1133 }
1134
1135 /* Set all windows to the new group */
1136 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) {
1137 tbl = container->tables[i];
1138
1139 if (!tbl)
1140 continue;
1141
1142 /* Set the default window to a new group */
1143 ret = table_group->ops->set_window(table_group, i, tbl);
1144 if (ret)
1145 goto release_exit;
1146 }
1147
1148 return 0;
1149
1150 release_exit:
1151 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i)
1152 table_group->ops->unset_window(table_group, i);
1153
1154 table_group->ops->release_ownership(table_group);
1155
1156 return ret;
1157 }
1158
1159 static int tce_iommu_attach_group(void *iommu_data,
1160 struct iommu_group *iommu_group)
1161 {
1162 int ret;
1163 struct tce_container *container = iommu_data;
1164 struct iommu_table_group *table_group;
1165 struct tce_iommu_group *tcegrp = NULL;
1166
1167 mutex_lock(&container->lock);
1168
1169 /* pr_debug("tce_vfio: Attaching group #%u to iommu %p\n",
1170 iommu_group_id(iommu_group), iommu_group); */
1171 table_group = iommu_group_get_iommudata(iommu_group);
1172
1173 if (tce_groups_attached(container) && (!table_group->ops ||
1174 !table_group->ops->take_ownership ||
1175 !table_group->ops->release_ownership)) {
1176 ret = -EBUSY;
1177 goto unlock_exit;
1178 }
1179
1180 /* Check if new group has the same iommu_ops (i.e. compatible) */
1181 list_for_each_entry(tcegrp, &container->group_list, next) {
1182 struct iommu_table_group *table_group_tmp;
1183
1184 if (tcegrp->grp == iommu_group) {
1185 pr_warn("tce_vfio: Group %d is already attached\n",
1186 iommu_group_id(iommu_group));
1187 ret = -EBUSY;
1188 goto unlock_exit;
1189 }
1190 table_group_tmp = iommu_group_get_iommudata(tcegrp->grp);
1191 if (table_group_tmp->ops != table_group->ops) {
1192 pr_warn("tce_vfio: Group %d is incompatible with group %d\n",
1193 iommu_group_id(iommu_group),
1194 iommu_group_id(tcegrp->grp));
1195 ret = -EPERM;
1196 goto unlock_exit;
1197 }
1198 }
1199
1200 tcegrp = kzalloc(sizeof(*tcegrp), GFP_KERNEL);
1201 if (!tcegrp) {
1202 ret = -ENOMEM;
1203 goto unlock_exit;
1204 }
1205
1206 if (!table_group->ops || !table_group->ops->take_ownership ||
1207 !table_group->ops->release_ownership)
1208 ret = tce_iommu_take_ownership(container, table_group);
1209 else
1210 ret = tce_iommu_take_ownership_ddw(container, table_group);
1211
1212 if (!ret) {
1213 tcegrp->grp = iommu_group;
1214 list_add(&tcegrp->next, &container->group_list);
1215 }
1216
1217 unlock_exit:
1218 if (ret && tcegrp)
1219 kfree(tcegrp);
1220
1221 mutex_unlock(&container->lock);
1222
1223 return ret;
1224 }
1225
1226 static void tce_iommu_detach_group(void *iommu_data,
1227 struct iommu_group *iommu_group)
1228 {
1229 struct tce_container *container = iommu_data;
1230 struct iommu_table_group *table_group;
1231 bool found = false;
1232 struct tce_iommu_group *tcegrp;
1233
1234 mutex_lock(&container->lock);
1235
1236 list_for_each_entry(tcegrp, &container->group_list, next) {
1237 if (tcegrp->grp == iommu_group) {
1238 found = true;
1239 break;
1240 }
1241 }
1242
1243 if (!found) {
1244 pr_warn("tce_vfio: detaching unattached group #%u\n",
1245 iommu_group_id(iommu_group));
1246 goto unlock_exit;
1247 }
1248
1249 list_del(&tcegrp->next);
1250 kfree(tcegrp);
1251
1252 table_group = iommu_group_get_iommudata(iommu_group);
1253 BUG_ON(!table_group);
1254
1255 if (!table_group->ops || !table_group->ops->release_ownership)
1256 tce_iommu_release_ownership(container, table_group);
1257 else
1258 tce_iommu_release_ownership_ddw(container, table_group);
1259
1260 unlock_exit:
1261 mutex_unlock(&container->lock);
1262 }
1263
1264 const struct vfio_iommu_driver_ops tce_iommu_driver_ops = {
1265 .name = "iommu-vfio-powerpc",
1266 .owner = THIS_MODULE,
1267 .open = tce_iommu_open,
1268 .release = tce_iommu_release,
1269 .ioctl = tce_iommu_ioctl,
1270 .attach_group = tce_iommu_attach_group,
1271 .detach_group = tce_iommu_detach_group,
1272 };
1273
1274 static int __init tce_iommu_init(void)
1275 {
1276 return vfio_register_iommu_driver(&tce_iommu_driver_ops);
1277 }
1278
1279 static void __exit tce_iommu_cleanup(void)
1280 {
1281 vfio_unregister_iommu_driver(&tce_iommu_driver_ops);
1282 }
1283
1284 module_init(tce_iommu_init);
1285 module_exit(tce_iommu_cleanup);
1286
1287 MODULE_VERSION(DRIVER_VERSION);
1288 MODULE_LICENSE("GPL v2");
1289 MODULE_AUTHOR(DRIVER_AUTHOR);
1290 MODULE_DESCRIPTION(DRIVER_DESC);
1291
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