1// SPDX-License-Identifier: GPL-2.0
2/*
3 * intel-pasid.c - PASID idr, table and entry manipulation
4 *
5 * Copyright (C) 2018 Intel Corporation
6 *
7 * Author: Lu Baolu <baolu.lu@linux.intel.com>
8 */
9
10#define pr_fmt(fmt) "DMAR: " fmt
11
12#include <linux/bitops.h>
13#include <linux/cpufeature.h>
14#include <linux/dmar.h>
15#include <linux/iommu.h>
16#include <linux/memory.h>
17#include <linux/pci.h>
18#include <linux/pci-ats.h>
19#include <linux/spinlock.h>
20
21#include "iommu.h"
22#include "pasid.h"
23
24/*
25 * Intel IOMMU system wide PASID name space:
26 */
27u32 intel_pasid_max_id = PASID_MAX;
28
29/*
30 * Per device pasid table management:
31 */
32
33/*
34 * Allocate a pasid table for @dev. It should be called in a
35 * single-thread context.
36 */
37int intel_pasid_alloc_table(struct device *dev)
38{
39 struct device_domain_info *info;
40 struct pasid_table *pasid_table;
41 struct page *pages;
42 u32 max_pasid = 0;
43 int order, size;
44
45 might_sleep();
46 info = dev_iommu_priv_get(dev);
47 if (WARN_ON(!info || !dev_is_pci(dev)))
48 return -ENODEV;
49 if (WARN_ON(info->pasid_table))
50 return -EEXIST;
51
52 pasid_table = kzalloc(size: sizeof(*pasid_table), GFP_KERNEL);
53 if (!pasid_table)
54 return -ENOMEM;
55
56 if (info->pasid_supported)
57 max_pasid = min_t(u32, pci_max_pasids(to_pci_dev(dev)),
58 intel_pasid_max_id);
59
60 size = max_pasid >> (PASID_PDE_SHIFT - 3);
61 order = size ? get_order(size) : 0;
62 pages = alloc_pages_node(nid: info->iommu->node,
63 GFP_KERNEL | __GFP_ZERO, order);
64 if (!pages) {
65 kfree(objp: pasid_table);
66 return -ENOMEM;
67 }
68
69 pasid_table->table = page_address(pages);
70 pasid_table->order = order;
71 pasid_table->max_pasid = 1 << (order + PAGE_SHIFT + 3);
72 info->pasid_table = pasid_table;
73
74 if (!ecap_coherent(info->iommu->ecap))
75 clflush_cache_range(addr: pasid_table->table, size: (1 << order) * PAGE_SIZE);
76
77 return 0;
78}
79
80void intel_pasid_free_table(struct device *dev)
81{
82 struct device_domain_info *info;
83 struct pasid_table *pasid_table;
84 struct pasid_dir_entry *dir;
85 struct pasid_entry *table;
86 int i, max_pde;
87
88 info = dev_iommu_priv_get(dev);
89 if (!info || !dev_is_pci(dev) || !info->pasid_table)
90 return;
91
92 pasid_table = info->pasid_table;
93 info->pasid_table = NULL;
94
95 /* Free scalable mode PASID directory tables: */
96 dir = pasid_table->table;
97 max_pde = pasid_table->max_pasid >> PASID_PDE_SHIFT;
98 for (i = 0; i < max_pde; i++) {
99 table = get_pasid_table_from_pde(pde: &dir[i]);
100 free_pgtable_page(vaddr: table);
101 }
102
103 free_pages(addr: (unsigned long)pasid_table->table, order: pasid_table->order);
104 kfree(objp: pasid_table);
105}
106
107struct pasid_table *intel_pasid_get_table(struct device *dev)
108{
109 struct device_domain_info *info;
110
111 info = dev_iommu_priv_get(dev);
112 if (!info)
113 return NULL;
114
115 return info->pasid_table;
116}
117
118static int intel_pasid_get_dev_max_id(struct device *dev)
119{
120 struct device_domain_info *info;
121
122 info = dev_iommu_priv_get(dev);
123 if (!info || !info->pasid_table)
124 return 0;
125
126 return info->pasid_table->max_pasid;
127}
128
129static struct pasid_entry *intel_pasid_get_entry(struct device *dev, u32 pasid)
130{
131 struct device_domain_info *info;
132 struct pasid_table *pasid_table;
133 struct pasid_dir_entry *dir;
134 struct pasid_entry *entries;
135 int dir_index, index;
136
137 pasid_table = intel_pasid_get_table(dev);
138 if (WARN_ON(!pasid_table || pasid >= intel_pasid_get_dev_max_id(dev)))
139 return NULL;
140
141 dir = pasid_table->table;
142 info = dev_iommu_priv_get(dev);
143 dir_index = pasid >> PASID_PDE_SHIFT;
144 index = pasid & PASID_PTE_MASK;
145
146retry:
147 entries = get_pasid_table_from_pde(pde: &dir[dir_index]);
148 if (!entries) {
149 entries = alloc_pgtable_page(node: info->iommu->node, GFP_ATOMIC);
150 if (!entries)
151 return NULL;
152
153 /*
154 * The pasid directory table entry won't be freed after
155 * allocation. No worry about the race with free and
156 * clear. However, this entry might be populated by others
157 * while we are preparing it. Use theirs with a retry.
158 */
159 if (cmpxchg64(&dir[dir_index].val, 0ULL,
160 (u64)virt_to_phys(entries) | PASID_PTE_PRESENT)) {
161 free_pgtable_page(vaddr: entries);
162 goto retry;
163 }
164 if (!ecap_coherent(info->iommu->ecap)) {
165 clflush_cache_range(addr: entries, VTD_PAGE_SIZE);
166 clflush_cache_range(addr: &dir[dir_index].val, size: sizeof(*dir));
167 }
168 }
169
170 return &entries[index];
171}
172
173/*
174 * Interfaces for PASID table entry manipulation:
175 */
176static void
177intel_pasid_clear_entry(struct device *dev, u32 pasid, bool fault_ignore)
178{
179 struct pasid_entry *pe;
180
181 pe = intel_pasid_get_entry(dev, pasid);
182 if (WARN_ON(!pe))
183 return;
184
185 if (fault_ignore && pasid_pte_is_present(pte: pe))
186 pasid_clear_entry_with_fpd(pe);
187 else
188 pasid_clear_entry(pe);
189}
190
191static void
192pasid_cache_invalidation_with_pasid(struct intel_iommu *iommu,
193 u16 did, u32 pasid)
194{
195 struct qi_desc desc;
196
197 desc.qw0 = QI_PC_DID(did) | QI_PC_GRAN(QI_PC_PASID_SEL) |
198 QI_PC_PASID(pasid) | QI_PC_TYPE;
199 desc.qw1 = 0;
200 desc.qw2 = 0;
201 desc.qw3 = 0;
202
203 qi_submit_sync(iommu, desc: &desc, count: 1, options: 0);
204}
205
206static void
207devtlb_invalidation_with_pasid(struct intel_iommu *iommu,
208 struct device *dev, u32 pasid)
209{
210 struct device_domain_info *info;
211 u16 sid, qdep, pfsid;
212
213 info = dev_iommu_priv_get(dev);
214 if (!info || !info->ats_enabled)
215 return;
216
217 if (pci_dev_is_disconnected(to_pci_dev(dev)))
218 return;
219
220 sid = info->bus << 8 | info->devfn;
221 qdep = info->ats_qdep;
222 pfsid = info->pfsid;
223
224 /*
225 * When PASID 0 is used, it indicates RID2PASID(DMA request w/o PASID),
226 * devTLB flush w/o PASID should be used. For non-zero PASID under
227 * SVA usage, device could do DMA with multiple PASIDs. It is more
228 * efficient to flush devTLB specific to the PASID.
229 */
230 if (pasid == IOMMU_NO_PASID)
231 qi_flush_dev_iotlb(iommu, sid, pfsid, qdep, addr: 0, mask: 64 - VTD_PAGE_SHIFT);
232 else
233 qi_flush_dev_iotlb_pasid(iommu, sid, pfsid, pasid, qdep, addr: 0, size_order: 64 - VTD_PAGE_SHIFT);
234}
235
236void intel_pasid_tear_down_entry(struct intel_iommu *iommu, struct device *dev,
237 u32 pasid, bool fault_ignore)
238{
239 struct pasid_entry *pte;
240 u16 did, pgtt;
241
242 spin_lock(lock: &iommu->lock);
243 pte = intel_pasid_get_entry(dev, pasid);
244 if (WARN_ON(!pte) || !pasid_pte_is_present(pte)) {
245 spin_unlock(lock: &iommu->lock);
246 return;
247 }
248
249 did = pasid_get_domain_id(pe: pte);
250 pgtt = pasid_pte_get_pgtt(pte);
251 intel_pasid_clear_entry(dev, pasid, fault_ignore);
252 spin_unlock(lock: &iommu->lock);
253
254 if (!ecap_coherent(iommu->ecap))
255 clflush_cache_range(addr: pte, size: sizeof(*pte));
256
257 pasid_cache_invalidation_with_pasid(iommu, did, pasid);
258
259 if (pgtt == PASID_ENTRY_PGTT_PT || pgtt == PASID_ENTRY_PGTT_FL_ONLY)
260 qi_flush_piotlb(iommu, did, pasid, addr: 0, npages: -1, ih: 0);
261 else
262 iommu->flush.flush_iotlb(iommu, did, 0, 0, DMA_TLB_DSI_FLUSH);
263
264 /* Device IOTLB doesn't need to be flushed in caching mode. */
265 if (!cap_caching_mode(iommu->cap))
266 devtlb_invalidation_with_pasid(iommu, dev, pasid);
267}
268
269/*
270 * This function flushes cache for a newly setup pasid table entry.
271 * Caller of it should not modify the in-use pasid table entries.
272 */
273static void pasid_flush_caches(struct intel_iommu *iommu,
274 struct pasid_entry *pte,
275 u32 pasid, u16 did)
276{
277 if (!ecap_coherent(iommu->ecap))
278 clflush_cache_range(addr: pte, size: sizeof(*pte));
279
280 if (cap_caching_mode(iommu->cap)) {
281 pasid_cache_invalidation_with_pasid(iommu, did, pasid);
282 qi_flush_piotlb(iommu, did, pasid, addr: 0, npages: -1, ih: 0);
283 } else {
284 iommu_flush_write_buffer(iommu);
285 }
286}
287
288/*
289 * Set up the scalable mode pasid table entry for first only
290 * translation type.
291 */
292int intel_pasid_setup_first_level(struct intel_iommu *iommu,
293 struct device *dev, pgd_t *pgd,
294 u32 pasid, u16 did, int flags)
295{
296 struct pasid_entry *pte;
297
298 if (!ecap_flts(iommu->ecap)) {
299 pr_err("No first level translation support on %s\n",
300 iommu->name);
301 return -EINVAL;
302 }
303
304 if ((flags & PASID_FLAG_FL5LP) && !cap_fl5lp_support(iommu->cap)) {
305 pr_err("No 5-level paging support for first-level on %s\n",
306 iommu->name);
307 return -EINVAL;
308 }
309
310 spin_lock(lock: &iommu->lock);
311 pte = intel_pasid_get_entry(dev, pasid);
312 if (!pte) {
313 spin_unlock(lock: &iommu->lock);
314 return -ENODEV;
315 }
316
317 if (pasid_pte_is_present(pte)) {
318 spin_unlock(lock: &iommu->lock);
319 return -EBUSY;
320 }
321
322 pasid_clear_entry(pe: pte);
323
324 /* Setup the first level page table pointer: */
325 pasid_set_flptr(pe: pte, value: (u64)__pa(pgd));
326
327 if (flags & PASID_FLAG_FL5LP)
328 pasid_set_flpm(pe: pte, value: 1);
329
330 if (flags & PASID_FLAG_PAGE_SNOOP)
331 pasid_set_pgsnp(pe: pte);
332
333 pasid_set_domain_id(pe: pte, value: did);
334 pasid_set_address_width(pe: pte, value: iommu->agaw);
335 pasid_set_page_snoop(pe: pte, value: !!ecap_smpwc(iommu->ecap));
336 pasid_set_nxe(pe: pte);
337
338 /* Setup Present and PASID Granular Transfer Type: */
339 pasid_set_translation_type(pe: pte, PASID_ENTRY_PGTT_FL_ONLY);
340 pasid_set_present(pe: pte);
341 spin_unlock(lock: &iommu->lock);
342
343 pasid_flush_caches(iommu, pte, pasid, did);
344
345 return 0;
346}
347
348/*
349 * Skip top levels of page tables for iommu which has less agaw
350 * than default. Unnecessary for PT mode.
351 */
352static int iommu_skip_agaw(struct dmar_domain *domain,
353 struct intel_iommu *iommu,
354 struct dma_pte **pgd)
355{
356 int agaw;
357
358 for (agaw = domain->agaw; agaw > iommu->agaw; agaw--) {
359 *pgd = phys_to_virt(address: dma_pte_addr(pte: *pgd));
360 if (!dma_pte_present(pte: *pgd))
361 return -EINVAL;
362 }
363
364 return agaw;
365}
366
367/*
368 * Set up the scalable mode pasid entry for second only translation type.
369 */
370int intel_pasid_setup_second_level(struct intel_iommu *iommu,
371 struct dmar_domain *domain,
372 struct device *dev, u32 pasid)
373{
374 struct pasid_entry *pte;
375 struct dma_pte *pgd;
376 u64 pgd_val;
377 int agaw;
378 u16 did;
379
380 /*
381 * If hardware advertises no support for second level
382 * translation, return directly.
383 */
384 if (!ecap_slts(iommu->ecap)) {
385 pr_err("No second level translation support on %s\n",
386 iommu->name);
387 return -EINVAL;
388 }
389
390 pgd = domain->pgd;
391 agaw = iommu_skip_agaw(domain, iommu, pgd: &pgd);
392 if (agaw < 0) {
393 dev_err(dev, "Invalid domain page table\n");
394 return -EINVAL;
395 }
396
397 pgd_val = virt_to_phys(address: pgd);
398 did = domain_id_iommu(domain, iommu);
399
400 spin_lock(lock: &iommu->lock);
401 pte = intel_pasid_get_entry(dev, pasid);
402 if (!pte) {
403 spin_unlock(lock: &iommu->lock);
404 return -ENODEV;
405 }
406
407 if (pasid_pte_is_present(pte)) {
408 spin_unlock(lock: &iommu->lock);
409 return -EBUSY;
410 }
411
412 pasid_clear_entry(pe: pte);
413 pasid_set_domain_id(pe: pte, value: did);
414 pasid_set_slptr(pe: pte, value: pgd_val);
415 pasid_set_address_width(pe: pte, value: agaw);
416 pasid_set_translation_type(pe: pte, PASID_ENTRY_PGTT_SL_ONLY);
417 pasid_set_fault_enable(pe: pte);
418 pasid_set_page_snoop(pe: pte, value: !!ecap_smpwc(iommu->ecap));
419 if (domain->dirty_tracking)
420 pasid_set_ssade(pe: pte);
421
422 pasid_set_present(pe: pte);
423 spin_unlock(lock: &iommu->lock);
424
425 pasid_flush_caches(iommu, pte, pasid, did);
426
427 return 0;
428}
429
430/*
431 * Set up dirty tracking on a second only or nested translation type.
432 */
433int intel_pasid_setup_dirty_tracking(struct intel_iommu *iommu,
434 struct device *dev, u32 pasid,
435 bool enabled)
436{
437 struct pasid_entry *pte;
438 u16 did, pgtt;
439
440 spin_lock(lock: &iommu->lock);
441
442 pte = intel_pasid_get_entry(dev, pasid);
443 if (!pte) {
444 spin_unlock(lock: &iommu->lock);
445 dev_err_ratelimited(
446 dev, "Failed to get pasid entry of PASID %d\n", pasid);
447 return -ENODEV;
448 }
449
450 did = pasid_get_domain_id(pe: pte);
451 pgtt = pasid_pte_get_pgtt(pte);
452 if (pgtt != PASID_ENTRY_PGTT_SL_ONLY &&
453 pgtt != PASID_ENTRY_PGTT_NESTED) {
454 spin_unlock(lock: &iommu->lock);
455 dev_err_ratelimited(
456 dev,
457 "Dirty tracking not supported on translation type %d\n",
458 pgtt);
459 return -EOPNOTSUPP;
460 }
461
462 if (pasid_get_ssade(pe: pte) == enabled) {
463 spin_unlock(lock: &iommu->lock);
464 return 0;
465 }
466
467 if (enabled)
468 pasid_set_ssade(pe: pte);
469 else
470 pasid_clear_ssade(pe: pte);
471 spin_unlock(lock: &iommu->lock);
472
473 if (!ecap_coherent(iommu->ecap))
474 clflush_cache_range(addr: pte, size: sizeof(*pte));
475
476 /*
477 * From VT-d spec table 25 "Guidance to Software for Invalidations":
478 *
479 * - PASID-selective-within-Domain PASID-cache invalidation
480 * If (PGTT=SS or Nested)
481 * - Domain-selective IOTLB invalidation
482 * Else
483 * - PASID-selective PASID-based IOTLB invalidation
484 * - If (pasid is RID_PASID)
485 * - Global Device-TLB invalidation to affected functions
486 * Else
487 * - PASID-based Device-TLB invalidation (with S=1 and
488 * Addr[63:12]=0x7FFFFFFF_FFFFF) to affected functions
489 */
490 pasid_cache_invalidation_with_pasid(iommu, did, pasid);
491
492 iommu->flush.flush_iotlb(iommu, did, 0, 0, DMA_TLB_DSI_FLUSH);
493
494 /* Device IOTLB doesn't need to be flushed in caching mode. */
495 if (!cap_caching_mode(iommu->cap))
496 devtlb_invalidation_with_pasid(iommu, dev, pasid);
497
498 return 0;
499}
500
501/*
502 * Set up the scalable mode pasid entry for passthrough translation type.
503 */
504int intel_pasid_setup_pass_through(struct intel_iommu *iommu,
505 struct device *dev, u32 pasid)
506{
507 u16 did = FLPT_DEFAULT_DID;
508 struct pasid_entry *pte;
509
510 spin_lock(lock: &iommu->lock);
511 pte = intel_pasid_get_entry(dev, pasid);
512 if (!pte) {
513 spin_unlock(lock: &iommu->lock);
514 return -ENODEV;
515 }
516
517 if (pasid_pte_is_present(pte)) {
518 spin_unlock(lock: &iommu->lock);
519 return -EBUSY;
520 }
521
522 pasid_clear_entry(pe: pte);
523 pasid_set_domain_id(pe: pte, value: did);
524 pasid_set_address_width(pe: pte, value: iommu->agaw);
525 pasid_set_translation_type(pe: pte, PASID_ENTRY_PGTT_PT);
526 pasid_set_fault_enable(pe: pte);
527 pasid_set_page_snoop(pe: pte, value: !!ecap_smpwc(iommu->ecap));
528 pasid_set_present(pe: pte);
529 spin_unlock(lock: &iommu->lock);
530
531 pasid_flush_caches(iommu, pte, pasid, did);
532
533 return 0;
534}
535
536/*
537 * Set the page snoop control for a pasid entry which has been set up.
538 */
539void intel_pasid_setup_page_snoop_control(struct intel_iommu *iommu,
540 struct device *dev, u32 pasid)
541{
542 struct pasid_entry *pte;
543 u16 did;
544
545 spin_lock(lock: &iommu->lock);
546 pte = intel_pasid_get_entry(dev, pasid);
547 if (WARN_ON(!pte || !pasid_pte_is_present(pte))) {
548 spin_unlock(lock: &iommu->lock);
549 return;
550 }
551
552 pasid_set_pgsnp(pe: pte);
553 did = pasid_get_domain_id(pe: pte);
554 spin_unlock(lock: &iommu->lock);
555
556 if (!ecap_coherent(iommu->ecap))
557 clflush_cache_range(addr: pte, size: sizeof(*pte));
558
559 /*
560 * VT-d spec 3.4 table23 states guides for cache invalidation:
561 *
562 * - PASID-selective-within-Domain PASID-cache invalidation
563 * - PASID-selective PASID-based IOTLB invalidation
564 * - If (pasid is RID_PASID)
565 * - Global Device-TLB invalidation to affected functions
566 * Else
567 * - PASID-based Device-TLB invalidation (with S=1 and
568 * Addr[63:12]=0x7FFFFFFF_FFFFF) to affected functions
569 */
570 pasid_cache_invalidation_with_pasid(iommu, did, pasid);
571 qi_flush_piotlb(iommu, did, pasid, addr: 0, npages: -1, ih: 0);
572
573 /* Device IOTLB doesn't need to be flushed in caching mode. */
574 if (!cap_caching_mode(iommu->cap))
575 devtlb_invalidation_with_pasid(iommu, dev, pasid);
576}
577
578/**
579 * intel_pasid_setup_nested() - Set up PASID entry for nested translation.
580 * @iommu: IOMMU which the device belong to
581 * @dev: Device to be set up for translation
582 * @pasid: PASID to be programmed in the device PASID table
583 * @domain: User stage-1 domain nested on a stage-2 domain
584 *
585 * This is used for nested translation. The input domain should be
586 * nested type and nested on a parent with 'is_nested_parent' flag
587 * set.
588 */
589int intel_pasid_setup_nested(struct intel_iommu *iommu, struct device *dev,
590 u32 pasid, struct dmar_domain *domain)
591{
592 struct iommu_hwpt_vtd_s1 *s1_cfg = &domain->s1_cfg;
593 pgd_t *s1_gpgd = (pgd_t *)(uintptr_t)domain->s1_pgtbl;
594 struct dmar_domain *s2_domain = domain->s2_domain;
595 u16 did = domain_id_iommu(domain, iommu);
596 struct dma_pte *pgd = s2_domain->pgd;
597 struct pasid_entry *pte;
598
599 /* Address width should match the address width supported by hardware */
600 switch (s1_cfg->addr_width) {
601 case ADDR_WIDTH_4LEVEL:
602 break;
603 case ADDR_WIDTH_5LEVEL:
604 if (!cap_fl5lp_support(iommu->cap)) {
605 dev_err_ratelimited(dev,
606 "5-level paging not supported\n");
607 return -EINVAL;
608 }
609 break;
610 default:
611 dev_err_ratelimited(dev, "Invalid stage-1 address width %d\n",
612 s1_cfg->addr_width);
613 return -EINVAL;
614 }
615
616 if ((s1_cfg->flags & IOMMU_VTD_S1_SRE) && !ecap_srs(iommu->ecap)) {
617 pr_err_ratelimited("No supervisor request support on %s\n",
618 iommu->name);
619 return -EINVAL;
620 }
621
622 if ((s1_cfg->flags & IOMMU_VTD_S1_EAFE) && !ecap_eafs(iommu->ecap)) {
623 pr_err_ratelimited("No extended access flag support on %s\n",
624 iommu->name);
625 return -EINVAL;
626 }
627
628 spin_lock(lock: &iommu->lock);
629 pte = intel_pasid_get_entry(dev, pasid);
630 if (!pte) {
631 spin_unlock(lock: &iommu->lock);
632 return -ENODEV;
633 }
634 if (pasid_pte_is_present(pte)) {
635 spin_unlock(lock: &iommu->lock);
636 return -EBUSY;
637 }
638
639 pasid_clear_entry(pe: pte);
640
641 if (s1_cfg->addr_width == ADDR_WIDTH_5LEVEL)
642 pasid_set_flpm(pe: pte, value: 1);
643
644 pasid_set_flptr(pe: pte, value: (uintptr_t)s1_gpgd);
645
646 if (s1_cfg->flags & IOMMU_VTD_S1_SRE) {
647 pasid_set_sre(pe: pte);
648 if (s1_cfg->flags & IOMMU_VTD_S1_WPE)
649 pasid_set_wpe(pe: pte);
650 }
651
652 if (s1_cfg->flags & IOMMU_VTD_S1_EAFE)
653 pasid_set_eafe(pe: pte);
654
655 if (s2_domain->force_snooping)
656 pasid_set_pgsnp(pe: pte);
657
658 pasid_set_slptr(pe: pte, virt_to_phys(address: pgd));
659 pasid_set_fault_enable(pe: pte);
660 pasid_set_domain_id(pe: pte, value: did);
661 pasid_set_address_width(pe: pte, value: s2_domain->agaw);
662 pasid_set_page_snoop(pe: pte, value: !!ecap_smpwc(iommu->ecap));
663 if (s2_domain->dirty_tracking)
664 pasid_set_ssade(pe: pte);
665 pasid_set_translation_type(pe: pte, PASID_ENTRY_PGTT_NESTED);
666 pasid_set_present(pe: pte);
667 spin_unlock(lock: &iommu->lock);
668
669 pasid_flush_caches(iommu, pte, pasid, did);
670
671 return 0;
672}
673
674/*
675 * Interfaces to setup or teardown a pasid table to the scalable-mode
676 * context table entry:
677 */
678
679static void device_pasid_table_teardown(struct device *dev, u8 bus, u8 devfn)
680{
681 struct device_domain_info *info = dev_iommu_priv_get(dev);
682 struct intel_iommu *iommu = info->iommu;
683 struct context_entry *context;
684
685 spin_lock(lock: &iommu->lock);
686 context = iommu_context_addr(iommu, bus, devfn, alloc: false);
687 if (!context) {
688 spin_unlock(lock: &iommu->lock);
689 return;
690 }
691
692 context_clear_entry(context);
693 __iommu_flush_cache(iommu, addr: context, size: sizeof(*context));
694 spin_unlock(lock: &iommu->lock);
695
696 /*
697 * Cache invalidation for changes to a scalable-mode context table
698 * entry.
699 *
700 * Section 6.5.3.3 of the VT-d spec:
701 * - Device-selective context-cache invalidation;
702 * - Domain-selective PASID-cache invalidation to affected domains
703 * (can be skipped if all PASID entries were not-present);
704 * - Domain-selective IOTLB invalidation to affected domains;
705 * - Global Device-TLB invalidation to affected functions.
706 *
707 * The iommu has been parked in the blocking state. All domains have
708 * been detached from the device or PASID. The PASID and IOTLB caches
709 * have been invalidated during the domain detach path.
710 */
711 iommu->flush.flush_context(iommu, 0, PCI_DEVID(bus, devfn),
712 DMA_CCMD_MASK_NOBIT, DMA_CCMD_DEVICE_INVL);
713 devtlb_invalidation_with_pasid(iommu, dev, IOMMU_NO_PASID);
714}
715
716static int pci_pasid_table_teardown(struct pci_dev *pdev, u16 alias, void *data)
717{
718 struct device *dev = data;
719
720 if (dev == &pdev->dev)
721 device_pasid_table_teardown(dev, PCI_BUS_NUM(alias), devfn: alias & 0xff);
722
723 return 0;
724}
725
726void intel_pasid_teardown_sm_context(struct device *dev)
727{
728 struct device_domain_info *info = dev_iommu_priv_get(dev);
729
730 if (!dev_is_pci(dev)) {
731 device_pasid_table_teardown(dev, bus: info->bus, devfn: info->devfn);
732 return;
733 }
734
735 pci_for_each_dma_alias(to_pci_dev(dev), fn: pci_pasid_table_teardown, data: dev);
736}
737
738/*
739 * Get the PASID directory size for scalable mode context entry.
740 * Value of X in the PDTS field of a scalable mode context entry
741 * indicates PASID directory with 2^(X + 7) entries.
742 */
743static unsigned long context_get_sm_pds(struct pasid_table *table)
744{
745 unsigned long pds, max_pde;
746
747 max_pde = table->max_pasid >> PASID_PDE_SHIFT;
748 pds = find_first_bit(addr: &max_pde, MAX_NR_PASID_BITS);
749 if (pds < 7)
750 return 0;
751
752 return pds - 7;
753}
754
755static int context_entry_set_pasid_table(struct context_entry *context,
756 struct device *dev)
757{
758 struct device_domain_info *info = dev_iommu_priv_get(dev);
759 struct pasid_table *table = info->pasid_table;
760 struct intel_iommu *iommu = info->iommu;
761 unsigned long pds;
762
763 context_clear_entry(context);
764
765 pds = context_get_sm_pds(table);
766 context->lo = (u64)virt_to_phys(address: table->table) | context_pdts(pds);
767 context_set_sm_rid2pasid(context, IOMMU_NO_PASID);
768
769 if (info->ats_supported)
770 context_set_sm_dte(context);
771 if (info->pri_supported)
772 context_set_sm_pre(context);
773 if (info->pasid_supported)
774 context_set_pasid(context);
775
776 context_set_fault_enable(context);
777 context_set_present(context);
778 __iommu_flush_cache(iommu, addr: context, size: sizeof(*context));
779
780 return 0;
781}
782
783static int device_pasid_table_setup(struct device *dev, u8 bus, u8 devfn)
784{
785 struct device_domain_info *info = dev_iommu_priv_get(dev);
786 struct intel_iommu *iommu = info->iommu;
787 struct context_entry *context;
788
789 spin_lock(lock: &iommu->lock);
790 context = iommu_context_addr(iommu, bus, devfn, alloc: true);
791 if (!context) {
792 spin_unlock(lock: &iommu->lock);
793 return -ENOMEM;
794 }
795
796 if (context_present(context) && !context_copied(iommu, bus, devfn)) {
797 spin_unlock(lock: &iommu->lock);
798 return 0;
799 }
800
801 if (context_copied(iommu, bus, devfn)) {
802 context_clear_entry(context);
803 __iommu_flush_cache(iommu, addr: context, size: sizeof(*context));
804
805 /*
806 * For kdump cases, old valid entries may be cached due to
807 * the in-flight DMA and copied pgtable, but there is no
808 * unmapping behaviour for them, thus we need explicit cache
809 * flushes for all affected domain IDs and PASIDs used in
810 * the copied PASID table. Given that we have no idea about
811 * which domain IDs and PASIDs were used in the copied tables,
812 * upgrade them to global PASID and IOTLB cache invalidation.
813 */
814 iommu->flush.flush_context(iommu, 0,
815 PCI_DEVID(bus, devfn),
816 DMA_CCMD_MASK_NOBIT,
817 DMA_CCMD_DEVICE_INVL);
818 qi_flush_pasid_cache(iommu, did: 0, QI_PC_GLOBAL, pasid: 0);
819 iommu->flush.flush_iotlb(iommu, 0, 0, 0, DMA_TLB_GLOBAL_FLUSH);
820 devtlb_invalidation_with_pasid(iommu, dev, IOMMU_NO_PASID);
821
822 /*
823 * At this point, the device is supposed to finish reset at
824 * its driver probe stage, so no in-flight DMA will exist,
825 * and we don't need to worry anymore hereafter.
826 */
827 clear_context_copied(iommu, bus, devfn);
828 }
829
830 context_entry_set_pasid_table(context, dev);
831 spin_unlock(lock: &iommu->lock);
832
833 /*
834 * It's a non-present to present mapping. If hardware doesn't cache
835 * non-present entry we don't need to flush the caches. If it does
836 * cache non-present entries, then it does so in the special
837 * domain #0, which we have to flush:
838 */
839 if (cap_caching_mode(iommu->cap)) {
840 iommu->flush.flush_context(iommu, 0,
841 PCI_DEVID(bus, devfn),
842 DMA_CCMD_MASK_NOBIT,
843 DMA_CCMD_DEVICE_INVL);
844 iommu->flush.flush_iotlb(iommu, 0, 0, 0, DMA_TLB_DSI_FLUSH);
845 }
846
847 return 0;
848}
849
850static int pci_pasid_table_setup(struct pci_dev *pdev, u16 alias, void *data)
851{
852 struct device *dev = data;
853
854 if (dev != &pdev->dev)
855 return 0;
856
857 return device_pasid_table_setup(dev, PCI_BUS_NUM(alias), devfn: alias & 0xff);
858}
859
860/*
861 * Set the device's PASID table to its context table entry.
862 *
863 * The PASID table is set to the context entries of both device itself
864 * and its alias requester ID for DMA.
865 */
866int intel_pasid_setup_sm_context(struct device *dev)
867{
868 struct device_domain_info *info = dev_iommu_priv_get(dev);
869
870 if (!dev_is_pci(dev))
871 return device_pasid_table_setup(dev, bus: info->bus, devfn: info->devfn);
872
873 return pci_for_each_dma_alias(to_pci_dev(dev), fn: pci_pasid_table_setup, data: dev);
874}
875

source code of linux/drivers/iommu/intel/pasid.c