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/intel-iommu.h>
16 #include <linux/iommu.h>
17 #include <linux/memory.h>
18 #include <linux/pci.h>
19 #include <linux/pci-ats.h>
20 #include <linux/spinlock.h>
21
22 #include "intel-pasid.h"
23
24 /*
25 * Intel IOMMU system wide PASID name space:
26 */
27 static DEFINE_SPINLOCK(pasid_lock);
28 u32 intel_pasid_max_id = PASID_MAX;
29 static DEFINE_IDR(pasid_idr);
30
intel_pasid_alloc_id(void * ptr,int start,int end,gfp_t gfp)31 int intel_pasid_alloc_id(void *ptr, int start, int end, gfp_t gfp)
32 {
33 int ret, min, max;
34
35 min = max_t(int, start, PASID_MIN);
36 max = min_t(int, end, intel_pasid_max_id);
37
38 WARN_ON(in_interrupt());
39 idr_preload(gfp);
40 spin_lock(&pasid_lock);
41 ret = idr_alloc(&pasid_idr, ptr, min, max, GFP_ATOMIC);
42 spin_unlock(&pasid_lock);
43 idr_preload_end();
44
45 return ret;
46 }
47
intel_pasid_free_id(int pasid)48 void intel_pasid_free_id(int pasid)
49 {
50 spin_lock(&pasid_lock);
51 idr_remove(&pasid_idr, pasid);
52 spin_unlock(&pasid_lock);
53 }
54
intel_pasid_lookup_id(int pasid)55 void *intel_pasid_lookup_id(int pasid)
56 {
57 void *p;
58
59 spin_lock(&pasid_lock);
60 p = idr_find(&pasid_idr, pasid);
61 spin_unlock(&pasid_lock);
62
63 return p;
64 }
65
66 /*
67 * Per device pasid table management:
68 */
69 static inline void
device_attach_pasid_table(struct device_domain_info * info,struct pasid_table * pasid_table)70 device_attach_pasid_table(struct device_domain_info *info,
71 struct pasid_table *pasid_table)
72 {
73 info->pasid_table = pasid_table;
74 list_add(&info->table, &pasid_table->dev);
75 }
76
77 static inline void
device_detach_pasid_table(struct device_domain_info * info,struct pasid_table * pasid_table)78 device_detach_pasid_table(struct device_domain_info *info,
79 struct pasid_table *pasid_table)
80 {
81 info->pasid_table = NULL;
82 list_del(&info->table);
83 }
84
85 struct pasid_table_opaque {
86 struct pasid_table **pasid_table;
87 int segment;
88 int bus;
89 int devfn;
90 };
91
search_pasid_table(struct device_domain_info * info,void * opaque)92 static int search_pasid_table(struct device_domain_info *info, void *opaque)
93 {
94 struct pasid_table_opaque *data = opaque;
95
96 if (info->iommu->segment == data->segment &&
97 info->bus == data->bus &&
98 info->devfn == data->devfn &&
99 info->pasid_table) {
100 *data->pasid_table = info->pasid_table;
101 return 1;
102 }
103
104 return 0;
105 }
106
get_alias_pasid_table(struct pci_dev * pdev,u16 alias,void * opaque)107 static int get_alias_pasid_table(struct pci_dev *pdev, u16 alias, void *opaque)
108 {
109 struct pasid_table_opaque *data = opaque;
110
111 data->segment = pci_domain_nr(pdev->bus);
112 data->bus = PCI_BUS_NUM(alias);
113 data->devfn = alias & 0xff;
114
115 return for_each_device_domain(&search_pasid_table, data);
116 }
117
118 /*
119 * Allocate a pasid table for @dev. It should be called in a
120 * single-thread context.
121 */
intel_pasid_alloc_table(struct device * dev)122 int intel_pasid_alloc_table(struct device *dev)
123 {
124 struct device_domain_info *info;
125 struct pasid_table *pasid_table;
126 struct pasid_table_opaque data;
127 struct page *pages;
128 int max_pasid = 0;
129 int ret, order;
130 int size;
131
132 might_sleep();
133 info = dev->archdata.iommu;
134 if (WARN_ON(!info || !dev_is_pci(dev) || info->pasid_table))
135 return -EINVAL;
136
137 /* DMA alias device already has a pasid table, use it: */
138 data.pasid_table = &pasid_table;
139 ret = pci_for_each_dma_alias(to_pci_dev(dev),
140 &get_alias_pasid_table, &data);
141 if (ret)
142 goto attach_out;
143
144 pasid_table = kzalloc(sizeof(*pasid_table), GFP_KERNEL);
145 if (!pasid_table)
146 return -ENOMEM;
147 INIT_LIST_HEAD(&pasid_table->dev);
148
149 if (info->pasid_supported)
150 max_pasid = min_t(int, pci_max_pasids(to_pci_dev(dev)),
151 intel_pasid_max_id);
152
153 size = max_pasid >> (PASID_PDE_SHIFT - 3);
154 order = size ? get_order(size) : 0;
155 pages = alloc_pages_node(info->iommu->node,
156 GFP_KERNEL | __GFP_ZERO, order);
157 if (!pages) {
158 kfree(pasid_table);
159 return -ENOMEM;
160 }
161
162 pasid_table->table = page_address(pages);
163 pasid_table->order = order;
164 pasid_table->max_pasid = 1 << (order + PAGE_SHIFT + 3);
165
166 attach_out:
167 device_attach_pasid_table(info, pasid_table);
168
169 return 0;
170 }
171
intel_pasid_free_table(struct device * dev)172 void intel_pasid_free_table(struct device *dev)
173 {
174 struct device_domain_info *info;
175 struct pasid_table *pasid_table;
176 struct pasid_dir_entry *dir;
177 struct pasid_entry *table;
178 int i, max_pde;
179
180 info = dev->archdata.iommu;
181 if (!info || !dev_is_pci(dev) || !info->pasid_table)
182 return;
183
184 pasid_table = info->pasid_table;
185 device_detach_pasid_table(info, pasid_table);
186
187 if (!list_empty(&pasid_table->dev))
188 return;
189
190 /* Free scalable mode PASID directory tables: */
191 dir = pasid_table->table;
192 max_pde = pasid_table->max_pasid >> PASID_PDE_SHIFT;
193 for (i = 0; i < max_pde; i++) {
194 table = get_pasid_table_from_pde(&dir[i]);
195 free_pgtable_page(table);
196 }
197
198 free_pages((unsigned long)pasid_table->table, pasid_table->order);
199 kfree(pasid_table);
200 }
201
intel_pasid_get_table(struct device * dev)202 struct pasid_table *intel_pasid_get_table(struct device *dev)
203 {
204 struct device_domain_info *info;
205
206 info = dev->archdata.iommu;
207 if (!info)
208 return NULL;
209
210 return info->pasid_table;
211 }
212
intel_pasid_get_dev_max_id(struct device * dev)213 int intel_pasid_get_dev_max_id(struct device *dev)
214 {
215 struct device_domain_info *info;
216
217 info = dev->archdata.iommu;
218 if (!info || !info->pasid_table)
219 return 0;
220
221 return info->pasid_table->max_pasid;
222 }
223
intel_pasid_get_entry(struct device * dev,int pasid)224 struct pasid_entry *intel_pasid_get_entry(struct device *dev, int pasid)
225 {
226 struct device_domain_info *info;
227 struct pasid_table *pasid_table;
228 struct pasid_dir_entry *dir;
229 struct pasid_entry *entries;
230 int dir_index, index;
231
232 pasid_table = intel_pasid_get_table(dev);
233 if (WARN_ON(!pasid_table || pasid < 0 ||
234 pasid >= intel_pasid_get_dev_max_id(dev)))
235 return NULL;
236
237 dir = pasid_table->table;
238 info = dev->archdata.iommu;
239 dir_index = pasid >> PASID_PDE_SHIFT;
240 index = pasid & PASID_PTE_MASK;
241
242 spin_lock(&pasid_lock);
243 entries = get_pasid_table_from_pde(&dir[dir_index]);
244 if (!entries) {
245 entries = alloc_pgtable_page(info->iommu->node);
246 if (!entries) {
247 spin_unlock(&pasid_lock);
248 return NULL;
249 }
250
251 WRITE_ONCE(dir[dir_index].val,
252 (u64)virt_to_phys(entries) | PASID_PTE_PRESENT);
253 }
254 spin_unlock(&pasid_lock);
255
256 return &entries[index];
257 }
258
259 /*
260 * Interfaces for PASID table entry manipulation:
261 */
pasid_clear_entry(struct pasid_entry * pe)262 static inline void pasid_clear_entry(struct pasid_entry *pe)
263 {
264 WRITE_ONCE(pe->val[0], 0);
265 WRITE_ONCE(pe->val[1], 0);
266 WRITE_ONCE(pe->val[2], 0);
267 WRITE_ONCE(pe->val[3], 0);
268 WRITE_ONCE(pe->val[4], 0);
269 WRITE_ONCE(pe->val[5], 0);
270 WRITE_ONCE(pe->val[6], 0);
271 WRITE_ONCE(pe->val[7], 0);
272 }
273
intel_pasid_clear_entry(struct device * dev,int pasid)274 static void intel_pasid_clear_entry(struct device *dev, int pasid)
275 {
276 struct pasid_entry *pe;
277
278 pe = intel_pasid_get_entry(dev, pasid);
279 if (WARN_ON(!pe))
280 return;
281
282 pasid_clear_entry(pe);
283 }
284
pasid_set_bits(u64 * ptr,u64 mask,u64 bits)285 static inline void pasid_set_bits(u64 *ptr, u64 mask, u64 bits)
286 {
287 u64 old;
288
289 old = READ_ONCE(*ptr);
290 WRITE_ONCE(*ptr, (old & ~mask) | bits);
291 }
292
293 /*
294 * Setup the DID(Domain Identifier) field (Bit 64~79) of scalable mode
295 * PASID entry.
296 */
297 static inline void
pasid_set_domain_id(struct pasid_entry * pe,u64 value)298 pasid_set_domain_id(struct pasid_entry *pe, u64 value)
299 {
300 pasid_set_bits(&pe->val[1], GENMASK_ULL(15, 0), value);
301 }
302
303 /*
304 * Get domain ID value of a scalable mode PASID entry.
305 */
306 static inline u16
pasid_get_domain_id(struct pasid_entry * pe)307 pasid_get_domain_id(struct pasid_entry *pe)
308 {
309 return (u16)(READ_ONCE(pe->val[1]) & GENMASK_ULL(15, 0));
310 }
311
312 /*
313 * Setup the SLPTPTR(Second Level Page Table Pointer) field (Bit 12~63)
314 * of a scalable mode PASID entry.
315 */
316 static inline void
pasid_set_slptr(struct pasid_entry * pe,u64 value)317 pasid_set_slptr(struct pasid_entry *pe, u64 value)
318 {
319 pasid_set_bits(&pe->val[0], VTD_PAGE_MASK, value);
320 }
321
322 /*
323 * Setup the AW(Address Width) field (Bit 2~4) of a scalable mode PASID
324 * entry.
325 */
326 static inline void
pasid_set_address_width(struct pasid_entry * pe,u64 value)327 pasid_set_address_width(struct pasid_entry *pe, u64 value)
328 {
329 pasid_set_bits(&pe->val[0], GENMASK_ULL(4, 2), value << 2);
330 }
331
332 /*
333 * Setup the PGTT(PASID Granular Translation Type) field (Bit 6~8)
334 * of a scalable mode PASID entry.
335 */
336 static inline void
pasid_set_translation_type(struct pasid_entry * pe,u64 value)337 pasid_set_translation_type(struct pasid_entry *pe, u64 value)
338 {
339 pasid_set_bits(&pe->val[0], GENMASK_ULL(8, 6), value << 6);
340 }
341
342 /*
343 * Enable fault processing by clearing the FPD(Fault Processing
344 * Disable) field (Bit 1) of a scalable mode PASID entry.
345 */
pasid_set_fault_enable(struct pasid_entry * pe)346 static inline void pasid_set_fault_enable(struct pasid_entry *pe)
347 {
348 pasid_set_bits(&pe->val[0], 1 << 1, 0);
349 }
350
351 /*
352 * Setup the SRE(Supervisor Request Enable) field (Bit 128) of a
353 * scalable mode PASID entry.
354 */
pasid_set_sre(struct pasid_entry * pe)355 static inline void pasid_set_sre(struct pasid_entry *pe)
356 {
357 pasid_set_bits(&pe->val[2], 1 << 0, 1);
358 }
359
360 /*
361 * Setup the P(Present) field (Bit 0) of a scalable mode PASID
362 * entry.
363 */
pasid_set_present(struct pasid_entry * pe)364 static inline void pasid_set_present(struct pasid_entry *pe)
365 {
366 pasid_set_bits(&pe->val[0], 1 << 0, 1);
367 }
368
369 /*
370 * Setup Page Walk Snoop bit (Bit 87) of a scalable mode PASID
371 * entry.
372 */
pasid_set_page_snoop(struct pasid_entry * pe,bool value)373 static inline void pasid_set_page_snoop(struct pasid_entry *pe, bool value)
374 {
375 pasid_set_bits(&pe->val[1], 1 << 23, value << 23);
376 }
377
378 /*
379 * Setup the First Level Page table Pointer field (Bit 140~191)
380 * of a scalable mode PASID entry.
381 */
382 static inline void
pasid_set_flptr(struct pasid_entry * pe,u64 value)383 pasid_set_flptr(struct pasid_entry *pe, u64 value)
384 {
385 pasid_set_bits(&pe->val[2], VTD_PAGE_MASK, value);
386 }
387
388 /*
389 * Setup the First Level Paging Mode field (Bit 130~131) of a
390 * scalable mode PASID entry.
391 */
392 static inline void
pasid_set_flpm(struct pasid_entry * pe,u64 value)393 pasid_set_flpm(struct pasid_entry *pe, u64 value)
394 {
395 pasid_set_bits(&pe->val[2], GENMASK_ULL(3, 2), value << 2);
396 }
397
398 static void
pasid_cache_invalidation_with_pasid(struct intel_iommu * iommu,u16 did,int pasid)399 pasid_cache_invalidation_with_pasid(struct intel_iommu *iommu,
400 u16 did, int pasid)
401 {
402 struct qi_desc desc;
403
404 desc.qw0 = QI_PC_DID(did) | QI_PC_PASID_SEL | QI_PC_PASID(pasid);
405 desc.qw1 = 0;
406 desc.qw2 = 0;
407 desc.qw3 = 0;
408
409 qi_submit_sync(&desc, iommu);
410 }
411
412 static void
iotlb_invalidation_with_pasid(struct intel_iommu * iommu,u16 did,u32 pasid)413 iotlb_invalidation_with_pasid(struct intel_iommu *iommu, u16 did, u32 pasid)
414 {
415 struct qi_desc desc;
416
417 desc.qw0 = QI_EIOTLB_PASID(pasid) | QI_EIOTLB_DID(did) |
418 QI_EIOTLB_GRAN(QI_GRAN_NONG_PASID) | QI_EIOTLB_TYPE;
419 desc.qw1 = 0;
420 desc.qw2 = 0;
421 desc.qw3 = 0;
422
423 qi_submit_sync(&desc, iommu);
424 }
425
426 static void
devtlb_invalidation_with_pasid(struct intel_iommu * iommu,struct device * dev,int pasid)427 devtlb_invalidation_with_pasid(struct intel_iommu *iommu,
428 struct device *dev, int pasid)
429 {
430 struct device_domain_info *info;
431 u16 sid, qdep, pfsid;
432
433 info = dev->archdata.iommu;
434 if (!info || !info->ats_enabled)
435 return;
436
437 sid = info->bus << 8 | info->devfn;
438 qdep = info->ats_qdep;
439 pfsid = info->pfsid;
440
441 qi_flush_dev_iotlb(iommu, sid, pfsid, qdep, 0, 64 - VTD_PAGE_SHIFT);
442 }
443
intel_pasid_tear_down_entry(struct intel_iommu * iommu,struct device * dev,int pasid)444 void intel_pasid_tear_down_entry(struct intel_iommu *iommu,
445 struct device *dev, int pasid)
446 {
447 struct pasid_entry *pte;
448 u16 did;
449
450 pte = intel_pasid_get_entry(dev, pasid);
451 if (WARN_ON(!pte))
452 return;
453
454 did = pasid_get_domain_id(pte);
455 intel_pasid_clear_entry(dev, pasid);
456
457 if (!ecap_coherent(iommu->ecap))
458 clflush_cache_range(pte, sizeof(*pte));
459
460 pasid_cache_invalidation_with_pasid(iommu, did, pasid);
461 iotlb_invalidation_with_pasid(iommu, did, pasid);
462
463 /* Device IOTLB doesn't need to be flushed in caching mode. */
464 if (!cap_caching_mode(iommu->cap))
465 devtlb_invalidation_with_pasid(iommu, dev, pasid);
466 }
467
468 /*
469 * Set up the scalable mode pasid table entry for first only
470 * translation type.
471 */
intel_pasid_setup_first_level(struct intel_iommu * iommu,struct device * dev,pgd_t * pgd,int pasid,u16 did,int flags)472 int intel_pasid_setup_first_level(struct intel_iommu *iommu,
473 struct device *dev, pgd_t *pgd,
474 int pasid, u16 did, int flags)
475 {
476 struct pasid_entry *pte;
477
478 if (!ecap_flts(iommu->ecap)) {
479 pr_err("No first level translation support on %s\n",
480 iommu->name);
481 return -EINVAL;
482 }
483
484 pte = intel_pasid_get_entry(dev, pasid);
485 if (WARN_ON(!pte))
486 return -EINVAL;
487
488 pasid_clear_entry(pte);
489
490 /* Setup the first level page table pointer: */
491 pasid_set_flptr(pte, (u64)__pa(pgd));
492 if (flags & PASID_FLAG_SUPERVISOR_MODE) {
493 if (!ecap_srs(iommu->ecap)) {
494 pr_err("No supervisor request support on %s\n",
495 iommu->name);
496 return -EINVAL;
497 }
498 pasid_set_sre(pte);
499 }
500
501 #ifdef CONFIG_X86
502 if (cpu_feature_enabled(X86_FEATURE_LA57))
503 pasid_set_flpm(pte, 1);
504 #endif /* CONFIG_X86 */
505
506 pasid_set_domain_id(pte, did);
507 pasid_set_address_width(pte, iommu->agaw);
508 pasid_set_page_snoop(pte, !!ecap_smpwc(iommu->ecap));
509
510 /* Setup Present and PASID Granular Transfer Type: */
511 pasid_set_translation_type(pte, 1);
512 pasid_set_present(pte);
513
514 if (!ecap_coherent(iommu->ecap))
515 clflush_cache_range(pte, sizeof(*pte));
516
517 if (cap_caching_mode(iommu->cap)) {
518 pasid_cache_invalidation_with_pasid(iommu, did, pasid);
519 iotlb_invalidation_with_pasid(iommu, did, pasid);
520 } else {
521 iommu_flush_write_buffer(iommu);
522 }
523
524 return 0;
525 }
526
527 /*
528 * Set up the scalable mode pasid entry for second only translation type.
529 */
intel_pasid_setup_second_level(struct intel_iommu * iommu,struct dmar_domain * domain,struct device * dev,int pasid)530 int intel_pasid_setup_second_level(struct intel_iommu *iommu,
531 struct dmar_domain *domain,
532 struct device *dev, int pasid)
533 {
534 struct pasid_entry *pte;
535 struct dma_pte *pgd;
536 u64 pgd_val;
537 int agaw;
538 u16 did;
539
540 /*
541 * If hardware advertises no support for second level
542 * translation, return directly.
543 */
544 if (!ecap_slts(iommu->ecap)) {
545 pr_err("No second level translation support on %s\n",
546 iommu->name);
547 return -EINVAL;
548 }
549
550 /*
551 * Skip top levels of page tables for iommu which has less agaw
552 * than default. Unnecessary for PT mode.
553 */
554 pgd = domain->pgd;
555 for (agaw = domain->agaw; agaw > iommu->agaw; agaw--) {
556 pgd = phys_to_virt(dma_pte_addr(pgd));
557 if (!dma_pte_present(pgd)) {
558 dev_err(dev, "Invalid domain page table\n");
559 return -EINVAL;
560 }
561 }
562
563 pgd_val = virt_to_phys(pgd);
564 did = domain->iommu_did[iommu->seq_id];
565
566 pte = intel_pasid_get_entry(dev, pasid);
567 if (!pte) {
568 dev_err(dev, "Failed to get pasid entry of PASID %d\n", pasid);
569 return -ENODEV;
570 }
571
572 pasid_clear_entry(pte);
573 pasid_set_domain_id(pte, did);
574 pasid_set_slptr(pte, pgd_val);
575 pasid_set_address_width(pte, agaw);
576 pasid_set_translation_type(pte, 2);
577 pasid_set_fault_enable(pte);
578 pasid_set_page_snoop(pte, !!ecap_smpwc(iommu->ecap));
579
580 /*
581 * Since it is a second level only translation setup, we should
582 * set SRE bit as well (addresses are expected to be GPAs).
583 */
584 pasid_set_sre(pte);
585 pasid_set_present(pte);
586
587 if (!ecap_coherent(iommu->ecap))
588 clflush_cache_range(pte, sizeof(*pte));
589
590 if (cap_caching_mode(iommu->cap)) {
591 pasid_cache_invalidation_with_pasid(iommu, did, pasid);
592 iotlb_invalidation_with_pasid(iommu, did, pasid);
593 } else {
594 iommu_flush_write_buffer(iommu);
595 }
596
597 return 0;
598 }
599
600 /*
601 * Set up the scalable mode pasid entry for passthrough translation type.
602 */
intel_pasid_setup_pass_through(struct intel_iommu * iommu,struct dmar_domain * domain,struct device * dev,int pasid)603 int intel_pasid_setup_pass_through(struct intel_iommu *iommu,
604 struct dmar_domain *domain,
605 struct device *dev, int pasid)
606 {
607 u16 did = FLPT_DEFAULT_DID;
608 struct pasid_entry *pte;
609
610 pte = intel_pasid_get_entry(dev, pasid);
611 if (!pte) {
612 dev_err(dev, "Failed to get pasid entry of PASID %d\n", pasid);
613 return -ENODEV;
614 }
615
616 pasid_clear_entry(pte);
617 pasid_set_domain_id(pte, did);
618 pasid_set_address_width(pte, iommu->agaw);
619 pasid_set_translation_type(pte, 4);
620 pasid_set_fault_enable(pte);
621 pasid_set_page_snoop(pte, !!ecap_smpwc(iommu->ecap));
622
623 /*
624 * We should set SRE bit as well since the addresses are expected
625 * to be GPAs.
626 */
627 pasid_set_sre(pte);
628 pasid_set_present(pte);
629
630 if (!ecap_coherent(iommu->ecap))
631 clflush_cache_range(pte, sizeof(*pte));
632
633 if (cap_caching_mode(iommu->cap)) {
634 pasid_cache_invalidation_with_pasid(iommu, did, pasid);
635 iotlb_invalidation_with_pasid(iommu, did, pasid);
636 } else {
637 iommu_flush_write_buffer(iommu);
638 }
639
640 return 0;
641 }
642