xref: /openbmc/linux/drivers/iommu/intel/pasid.c (revision 877d95dc)
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  */
27 u32 intel_pasid_max_id = PASID_MAX;
28 
29 int vcmd_alloc_pasid(struct intel_iommu *iommu, u32 *pasid)
30 {
31 	unsigned long flags;
32 	u8 status_code;
33 	int ret = 0;
34 	u64 res;
35 
36 	raw_spin_lock_irqsave(&iommu->register_lock, flags);
37 	dmar_writeq(iommu->reg + DMAR_VCMD_REG, VCMD_CMD_ALLOC);
38 	IOMMU_WAIT_OP(iommu, DMAR_VCRSP_REG, dmar_readq,
39 		      !(res & VCMD_VRSP_IP), res);
40 	raw_spin_unlock_irqrestore(&iommu->register_lock, flags);
41 
42 	status_code = VCMD_VRSP_SC(res);
43 	switch (status_code) {
44 	case VCMD_VRSP_SC_SUCCESS:
45 		*pasid = VCMD_VRSP_RESULT_PASID(res);
46 		break;
47 	case VCMD_VRSP_SC_NO_PASID_AVAIL:
48 		pr_info("IOMMU: %s: No PASID available\n", iommu->name);
49 		ret = -ENOSPC;
50 		break;
51 	default:
52 		ret = -ENODEV;
53 		pr_warn("IOMMU: %s: Unexpected error code %d\n",
54 			iommu->name, status_code);
55 	}
56 
57 	return ret;
58 }
59 
60 void vcmd_free_pasid(struct intel_iommu *iommu, u32 pasid)
61 {
62 	unsigned long flags;
63 	u8 status_code;
64 	u64 res;
65 
66 	raw_spin_lock_irqsave(&iommu->register_lock, flags);
67 	dmar_writeq(iommu->reg + DMAR_VCMD_REG,
68 		    VCMD_CMD_OPERAND(pasid) | VCMD_CMD_FREE);
69 	IOMMU_WAIT_OP(iommu, DMAR_VCRSP_REG, dmar_readq,
70 		      !(res & VCMD_VRSP_IP), res);
71 	raw_spin_unlock_irqrestore(&iommu->register_lock, flags);
72 
73 	status_code = VCMD_VRSP_SC(res);
74 	switch (status_code) {
75 	case VCMD_VRSP_SC_SUCCESS:
76 		break;
77 	case VCMD_VRSP_SC_INVALID_PASID:
78 		pr_info("IOMMU: %s: Invalid PASID\n", iommu->name);
79 		break;
80 	default:
81 		pr_warn("IOMMU: %s: Unexpected error code %d\n",
82 			iommu->name, status_code);
83 	}
84 }
85 
86 /*
87  * Per device pasid table management:
88  */
89 
90 /*
91  * Allocate a pasid table for @dev. It should be called in a
92  * single-thread context.
93  */
94 int intel_pasid_alloc_table(struct device *dev)
95 {
96 	struct device_domain_info *info;
97 	struct pasid_table *pasid_table;
98 	struct page *pages;
99 	u32 max_pasid = 0;
100 	int order, size;
101 
102 	might_sleep();
103 	info = dev_iommu_priv_get(dev);
104 	if (WARN_ON(!info || !dev_is_pci(dev) || info->pasid_table))
105 		return -EINVAL;
106 
107 	pasid_table = kzalloc(sizeof(*pasid_table), GFP_KERNEL);
108 	if (!pasid_table)
109 		return -ENOMEM;
110 
111 	if (info->pasid_supported)
112 		max_pasid = min_t(u32, pci_max_pasids(to_pci_dev(dev)),
113 				  intel_pasid_max_id);
114 
115 	size = max_pasid >> (PASID_PDE_SHIFT - 3);
116 	order = size ? get_order(size) : 0;
117 	pages = alloc_pages_node(info->iommu->node,
118 				 GFP_KERNEL | __GFP_ZERO, order);
119 	if (!pages) {
120 		kfree(pasid_table);
121 		return -ENOMEM;
122 	}
123 
124 	pasid_table->table = page_address(pages);
125 	pasid_table->order = order;
126 	pasid_table->max_pasid = 1 << (order + PAGE_SHIFT + 3);
127 	info->pasid_table = pasid_table;
128 
129 	return 0;
130 }
131 
132 void intel_pasid_free_table(struct device *dev)
133 {
134 	struct device_domain_info *info;
135 	struct pasid_table *pasid_table;
136 	struct pasid_dir_entry *dir;
137 	struct pasid_entry *table;
138 	int i, max_pde;
139 
140 	info = dev_iommu_priv_get(dev);
141 	if (!info || !dev_is_pci(dev) || !info->pasid_table)
142 		return;
143 
144 	pasid_table = info->pasid_table;
145 	info->pasid_table = NULL;
146 
147 	/* Free scalable mode PASID directory tables: */
148 	dir = pasid_table->table;
149 	max_pde = pasid_table->max_pasid >> PASID_PDE_SHIFT;
150 	for (i = 0; i < max_pde; i++) {
151 		table = get_pasid_table_from_pde(&dir[i]);
152 		free_pgtable_page(table);
153 	}
154 
155 	free_pages((unsigned long)pasid_table->table, pasid_table->order);
156 	kfree(pasid_table);
157 }
158 
159 struct pasid_table *intel_pasid_get_table(struct device *dev)
160 {
161 	struct device_domain_info *info;
162 
163 	info = dev_iommu_priv_get(dev);
164 	if (!info)
165 		return NULL;
166 
167 	return info->pasid_table;
168 }
169 
170 static int intel_pasid_get_dev_max_id(struct device *dev)
171 {
172 	struct device_domain_info *info;
173 
174 	info = dev_iommu_priv_get(dev);
175 	if (!info || !info->pasid_table)
176 		return 0;
177 
178 	return info->pasid_table->max_pasid;
179 }
180 
181 static struct pasid_entry *intel_pasid_get_entry(struct device *dev, u32 pasid)
182 {
183 	struct device_domain_info *info;
184 	struct pasid_table *pasid_table;
185 	struct pasid_dir_entry *dir;
186 	struct pasid_entry *entries;
187 	int dir_index, index;
188 
189 	pasid_table = intel_pasid_get_table(dev);
190 	if (WARN_ON(!pasid_table || pasid >= intel_pasid_get_dev_max_id(dev)))
191 		return NULL;
192 
193 	dir = pasid_table->table;
194 	info = dev_iommu_priv_get(dev);
195 	dir_index = pasid >> PASID_PDE_SHIFT;
196 	index = pasid & PASID_PTE_MASK;
197 
198 retry:
199 	entries = get_pasid_table_from_pde(&dir[dir_index]);
200 	if (!entries) {
201 		entries = alloc_pgtable_page(info->iommu->node);
202 		if (!entries)
203 			return NULL;
204 
205 		/*
206 		 * The pasid directory table entry won't be freed after
207 		 * allocation. No worry about the race with free and
208 		 * clear. However, this entry might be populated by others
209 		 * while we are preparing it. Use theirs with a retry.
210 		 */
211 		if (cmpxchg64(&dir[dir_index].val, 0ULL,
212 			      (u64)virt_to_phys(entries) | PASID_PTE_PRESENT)) {
213 			free_pgtable_page(entries);
214 			goto retry;
215 		}
216 	}
217 
218 	return &entries[index];
219 }
220 
221 /*
222  * Interfaces for PASID table entry manipulation:
223  */
224 static inline void pasid_clear_entry(struct pasid_entry *pe)
225 {
226 	WRITE_ONCE(pe->val[0], 0);
227 	WRITE_ONCE(pe->val[1], 0);
228 	WRITE_ONCE(pe->val[2], 0);
229 	WRITE_ONCE(pe->val[3], 0);
230 	WRITE_ONCE(pe->val[4], 0);
231 	WRITE_ONCE(pe->val[5], 0);
232 	WRITE_ONCE(pe->val[6], 0);
233 	WRITE_ONCE(pe->val[7], 0);
234 }
235 
236 static inline void pasid_clear_entry_with_fpd(struct pasid_entry *pe)
237 {
238 	WRITE_ONCE(pe->val[0], PASID_PTE_FPD);
239 	WRITE_ONCE(pe->val[1], 0);
240 	WRITE_ONCE(pe->val[2], 0);
241 	WRITE_ONCE(pe->val[3], 0);
242 	WRITE_ONCE(pe->val[4], 0);
243 	WRITE_ONCE(pe->val[5], 0);
244 	WRITE_ONCE(pe->val[6], 0);
245 	WRITE_ONCE(pe->val[7], 0);
246 }
247 
248 static void
249 intel_pasid_clear_entry(struct device *dev, u32 pasid, bool fault_ignore)
250 {
251 	struct pasid_entry *pe;
252 
253 	pe = intel_pasid_get_entry(dev, pasid);
254 	if (WARN_ON(!pe))
255 		return;
256 
257 	if (fault_ignore && pasid_pte_is_present(pe))
258 		pasid_clear_entry_with_fpd(pe);
259 	else
260 		pasid_clear_entry(pe);
261 }
262 
263 static inline void pasid_set_bits(u64 *ptr, u64 mask, u64 bits)
264 {
265 	u64 old;
266 
267 	old = READ_ONCE(*ptr);
268 	WRITE_ONCE(*ptr, (old & ~mask) | bits);
269 }
270 
271 /*
272  * Setup the DID(Domain Identifier) field (Bit 64~79) of scalable mode
273  * PASID entry.
274  */
275 static inline void
276 pasid_set_domain_id(struct pasid_entry *pe, u64 value)
277 {
278 	pasid_set_bits(&pe->val[1], GENMASK_ULL(15, 0), value);
279 }
280 
281 /*
282  * Get domain ID value of a scalable mode PASID entry.
283  */
284 static inline u16
285 pasid_get_domain_id(struct pasid_entry *pe)
286 {
287 	return (u16)(READ_ONCE(pe->val[1]) & GENMASK_ULL(15, 0));
288 }
289 
290 /*
291  * Setup the SLPTPTR(Second Level Page Table Pointer) field (Bit 12~63)
292  * of a scalable mode PASID entry.
293  */
294 static inline void
295 pasid_set_slptr(struct pasid_entry *pe, u64 value)
296 {
297 	pasid_set_bits(&pe->val[0], VTD_PAGE_MASK, value);
298 }
299 
300 /*
301  * Setup the AW(Address Width) field (Bit 2~4) of a scalable mode PASID
302  * entry.
303  */
304 static inline void
305 pasid_set_address_width(struct pasid_entry *pe, u64 value)
306 {
307 	pasid_set_bits(&pe->val[0], GENMASK_ULL(4, 2), value << 2);
308 }
309 
310 /*
311  * Setup the PGTT(PASID Granular Translation Type) field (Bit 6~8)
312  * of a scalable mode PASID entry.
313  */
314 static inline void
315 pasid_set_translation_type(struct pasid_entry *pe, u64 value)
316 {
317 	pasid_set_bits(&pe->val[0], GENMASK_ULL(8, 6), value << 6);
318 }
319 
320 /*
321  * Enable fault processing by clearing the FPD(Fault Processing
322  * Disable) field (Bit 1) of a scalable mode PASID entry.
323  */
324 static inline void pasid_set_fault_enable(struct pasid_entry *pe)
325 {
326 	pasid_set_bits(&pe->val[0], 1 << 1, 0);
327 }
328 
329 /*
330  * Setup the SRE(Supervisor Request Enable) field (Bit 128) of a
331  * scalable mode PASID entry.
332  */
333 static inline void pasid_set_sre(struct pasid_entry *pe)
334 {
335 	pasid_set_bits(&pe->val[2], 1 << 0, 1);
336 }
337 
338 /*
339  * Setup the WPE(Write Protect Enable) field (Bit 132) of a
340  * scalable mode PASID entry.
341  */
342 static inline void pasid_set_wpe(struct pasid_entry *pe)
343 {
344 	pasid_set_bits(&pe->val[2], 1 << 4, 1 << 4);
345 }
346 
347 /*
348  * Setup the P(Present) field (Bit 0) of a scalable mode PASID
349  * entry.
350  */
351 static inline void pasid_set_present(struct pasid_entry *pe)
352 {
353 	pasid_set_bits(&pe->val[0], 1 << 0, 1);
354 }
355 
356 /*
357  * Setup Page Walk Snoop bit (Bit 87) of a scalable mode PASID
358  * entry.
359  */
360 static inline void pasid_set_page_snoop(struct pasid_entry *pe, bool value)
361 {
362 	pasid_set_bits(&pe->val[1], 1 << 23, value << 23);
363 }
364 
365 /*
366  * Setup the Page Snoop (PGSNP) field (Bit 88) of a scalable mode
367  * PASID entry.
368  */
369 static inline void
370 pasid_set_pgsnp(struct pasid_entry *pe)
371 {
372 	pasid_set_bits(&pe->val[1], 1ULL << 24, 1ULL << 24);
373 }
374 
375 /*
376  * Setup the First Level Page table Pointer field (Bit 140~191)
377  * of a scalable mode PASID entry.
378  */
379 static inline void
380 pasid_set_flptr(struct pasid_entry *pe, u64 value)
381 {
382 	pasid_set_bits(&pe->val[2], VTD_PAGE_MASK, value);
383 }
384 
385 /*
386  * Setup the First Level Paging Mode field (Bit 130~131) of a
387  * scalable mode PASID entry.
388  */
389 static inline void
390 pasid_set_flpm(struct pasid_entry *pe, u64 value)
391 {
392 	pasid_set_bits(&pe->val[2], GENMASK_ULL(3, 2), value << 2);
393 }
394 
395 /*
396  * Setup the Extended Access Flag Enable (EAFE) field (Bit 135)
397  * of a scalable mode PASID entry.
398  */
399 static inline void
400 pasid_set_eafe(struct pasid_entry *pe)
401 {
402 	pasid_set_bits(&pe->val[2], 1 << 7, 1 << 7);
403 }
404 
405 static void
406 pasid_cache_invalidation_with_pasid(struct intel_iommu *iommu,
407 				    u16 did, u32 pasid)
408 {
409 	struct qi_desc desc;
410 
411 	desc.qw0 = QI_PC_DID(did) | QI_PC_GRAN(QI_PC_PASID_SEL) |
412 		QI_PC_PASID(pasid) | QI_PC_TYPE;
413 	desc.qw1 = 0;
414 	desc.qw2 = 0;
415 	desc.qw3 = 0;
416 
417 	qi_submit_sync(iommu, &desc, 1, 0);
418 }
419 
420 static void
421 devtlb_invalidation_with_pasid(struct intel_iommu *iommu,
422 			       struct device *dev, u32 pasid)
423 {
424 	struct device_domain_info *info;
425 	u16 sid, qdep, pfsid;
426 
427 	info = dev_iommu_priv_get(dev);
428 	if (!info || !info->ats_enabled)
429 		return;
430 
431 	sid = info->bus << 8 | info->devfn;
432 	qdep = info->ats_qdep;
433 	pfsid = info->pfsid;
434 
435 	/*
436 	 * When PASID 0 is used, it indicates RID2PASID(DMA request w/o PASID),
437 	 * devTLB flush w/o PASID should be used. For non-zero PASID under
438 	 * SVA usage, device could do DMA with multiple PASIDs. It is more
439 	 * efficient to flush devTLB specific to the PASID.
440 	 */
441 	if (pasid == PASID_RID2PASID)
442 		qi_flush_dev_iotlb(iommu, sid, pfsid, qdep, 0, 64 - VTD_PAGE_SHIFT);
443 	else
444 		qi_flush_dev_iotlb_pasid(iommu, sid, pfsid, pasid, qdep, 0, 64 - VTD_PAGE_SHIFT);
445 }
446 
447 void intel_pasid_tear_down_entry(struct intel_iommu *iommu, struct device *dev,
448 				 u32 pasid, bool fault_ignore)
449 {
450 	struct pasid_entry *pte;
451 	u16 did, pgtt;
452 
453 	spin_lock(&iommu->lock);
454 	pte = intel_pasid_get_entry(dev, pasid);
455 	if (WARN_ON(!pte) || !pasid_pte_is_present(pte)) {
456 		spin_unlock(&iommu->lock);
457 		return;
458 	}
459 
460 	did = pasid_get_domain_id(pte);
461 	pgtt = pasid_pte_get_pgtt(pte);
462 	intel_pasid_clear_entry(dev, pasid, fault_ignore);
463 	spin_unlock(&iommu->lock);
464 
465 	if (!ecap_coherent(iommu->ecap))
466 		clflush_cache_range(pte, sizeof(*pte));
467 
468 	pasid_cache_invalidation_with_pasid(iommu, did, pasid);
469 
470 	if (pgtt == PASID_ENTRY_PGTT_PT || pgtt == PASID_ENTRY_PGTT_FL_ONLY)
471 		qi_flush_piotlb(iommu, did, pasid, 0, -1, 0);
472 	else
473 		iommu->flush.flush_iotlb(iommu, did, 0, 0, DMA_TLB_DSI_FLUSH);
474 
475 	/* Device IOTLB doesn't need to be flushed in caching mode. */
476 	if (!cap_caching_mode(iommu->cap))
477 		devtlb_invalidation_with_pasid(iommu, dev, pasid);
478 }
479 
480 /*
481  * This function flushes cache for a newly setup pasid table entry.
482  * Caller of it should not modify the in-use pasid table entries.
483  */
484 static void pasid_flush_caches(struct intel_iommu *iommu,
485 				struct pasid_entry *pte,
486 			       u32 pasid, u16 did)
487 {
488 	if (!ecap_coherent(iommu->ecap))
489 		clflush_cache_range(pte, sizeof(*pte));
490 
491 	if (cap_caching_mode(iommu->cap)) {
492 		pasid_cache_invalidation_with_pasid(iommu, did, pasid);
493 		qi_flush_piotlb(iommu, did, pasid, 0, -1, 0);
494 	} else {
495 		iommu_flush_write_buffer(iommu);
496 	}
497 }
498 
499 /*
500  * Set up the scalable mode pasid table entry for first only
501  * translation type.
502  */
503 int intel_pasid_setup_first_level(struct intel_iommu *iommu,
504 				  struct device *dev, pgd_t *pgd,
505 				  u32 pasid, u16 did, int flags)
506 {
507 	struct pasid_entry *pte;
508 
509 	if (!ecap_flts(iommu->ecap)) {
510 		pr_err("No first level translation support on %s\n",
511 		       iommu->name);
512 		return -EINVAL;
513 	}
514 
515 	if (flags & PASID_FLAG_SUPERVISOR_MODE) {
516 #ifdef CONFIG_X86
517 		unsigned long cr0 = read_cr0();
518 
519 		/* CR0.WP is normally set but just to be sure */
520 		if (unlikely(!(cr0 & X86_CR0_WP))) {
521 			pr_err("No CPU write protect!\n");
522 			return -EINVAL;
523 		}
524 #endif
525 		if (!ecap_srs(iommu->ecap)) {
526 			pr_err("No supervisor request support on %s\n",
527 			       iommu->name);
528 			return -EINVAL;
529 		}
530 	}
531 
532 	if ((flags & PASID_FLAG_FL5LP) && !cap_5lp_support(iommu->cap)) {
533 		pr_err("No 5-level paging support for first-level on %s\n",
534 		       iommu->name);
535 		return -EINVAL;
536 	}
537 
538 	spin_lock(&iommu->lock);
539 	pte = intel_pasid_get_entry(dev, pasid);
540 	if (!pte) {
541 		spin_unlock(&iommu->lock);
542 		return -ENODEV;
543 	}
544 
545 	if (pasid_pte_is_present(pte)) {
546 		spin_unlock(&iommu->lock);
547 		return -EBUSY;
548 	}
549 
550 	pasid_clear_entry(pte);
551 
552 	/* Setup the first level page table pointer: */
553 	pasid_set_flptr(pte, (u64)__pa(pgd));
554 	if (flags & PASID_FLAG_SUPERVISOR_MODE) {
555 		pasid_set_sre(pte);
556 		pasid_set_wpe(pte);
557 	}
558 
559 	if (flags & PASID_FLAG_FL5LP)
560 		pasid_set_flpm(pte, 1);
561 
562 	if (flags & PASID_FLAG_PAGE_SNOOP)
563 		pasid_set_pgsnp(pte);
564 
565 	pasid_set_domain_id(pte, did);
566 	pasid_set_address_width(pte, iommu->agaw);
567 	pasid_set_page_snoop(pte, !!ecap_smpwc(iommu->ecap));
568 
569 	/* Setup Present and PASID Granular Transfer Type: */
570 	pasid_set_translation_type(pte, PASID_ENTRY_PGTT_FL_ONLY);
571 	pasid_set_present(pte);
572 	spin_unlock(&iommu->lock);
573 
574 	pasid_flush_caches(iommu, pte, pasid, did);
575 
576 	return 0;
577 }
578 
579 /*
580  * Skip top levels of page tables for iommu which has less agaw
581  * than default. Unnecessary for PT mode.
582  */
583 static inline int iommu_skip_agaw(struct dmar_domain *domain,
584 				  struct intel_iommu *iommu,
585 				  struct dma_pte **pgd)
586 {
587 	int agaw;
588 
589 	for (agaw = domain->agaw; agaw > iommu->agaw; agaw--) {
590 		*pgd = phys_to_virt(dma_pte_addr(*pgd));
591 		if (!dma_pte_present(*pgd))
592 			return -EINVAL;
593 	}
594 
595 	return agaw;
596 }
597 
598 /*
599  * Set up the scalable mode pasid entry for second only translation type.
600  */
601 int intel_pasid_setup_second_level(struct intel_iommu *iommu,
602 				   struct dmar_domain *domain,
603 				   struct device *dev, u32 pasid)
604 {
605 	struct pasid_entry *pte;
606 	struct dma_pte *pgd;
607 	u64 pgd_val;
608 	int agaw;
609 	u16 did;
610 
611 	/*
612 	 * If hardware advertises no support for second level
613 	 * translation, return directly.
614 	 */
615 	if (!ecap_slts(iommu->ecap)) {
616 		pr_err("No second level translation support on %s\n",
617 		       iommu->name);
618 		return -EINVAL;
619 	}
620 
621 	pgd = domain->pgd;
622 	agaw = iommu_skip_agaw(domain, iommu, &pgd);
623 	if (agaw < 0) {
624 		dev_err(dev, "Invalid domain page table\n");
625 		return -EINVAL;
626 	}
627 
628 	pgd_val = virt_to_phys(pgd);
629 	did = domain_id_iommu(domain, iommu);
630 
631 	spin_lock(&iommu->lock);
632 	pte = intel_pasid_get_entry(dev, pasid);
633 	if (!pte) {
634 		spin_unlock(&iommu->lock);
635 		return -ENODEV;
636 	}
637 
638 	if (pasid_pte_is_present(pte)) {
639 		spin_unlock(&iommu->lock);
640 		return -EBUSY;
641 	}
642 
643 	pasid_clear_entry(pte);
644 	pasid_set_domain_id(pte, did);
645 	pasid_set_slptr(pte, pgd_val);
646 	pasid_set_address_width(pte, agaw);
647 	pasid_set_translation_type(pte, PASID_ENTRY_PGTT_SL_ONLY);
648 	pasid_set_fault_enable(pte);
649 	pasid_set_page_snoop(pte, !!ecap_smpwc(iommu->ecap));
650 
651 	/*
652 	 * Since it is a second level only translation setup, we should
653 	 * set SRE bit as well (addresses are expected to be GPAs).
654 	 */
655 	if (pasid != PASID_RID2PASID)
656 		pasid_set_sre(pte);
657 	pasid_set_present(pte);
658 	spin_unlock(&iommu->lock);
659 
660 	pasid_flush_caches(iommu, pte, pasid, did);
661 
662 	return 0;
663 }
664 
665 /*
666  * Set up the scalable mode pasid entry for passthrough translation type.
667  */
668 int intel_pasid_setup_pass_through(struct intel_iommu *iommu,
669 				   struct dmar_domain *domain,
670 				   struct device *dev, u32 pasid)
671 {
672 	u16 did = FLPT_DEFAULT_DID;
673 	struct pasid_entry *pte;
674 
675 	spin_lock(&iommu->lock);
676 	pte = intel_pasid_get_entry(dev, pasid);
677 	if (!pte) {
678 		spin_unlock(&iommu->lock);
679 		return -ENODEV;
680 	}
681 
682 	if (pasid_pte_is_present(pte)) {
683 		spin_unlock(&iommu->lock);
684 		return -EBUSY;
685 	}
686 
687 	pasid_clear_entry(pte);
688 	pasid_set_domain_id(pte, did);
689 	pasid_set_address_width(pte, iommu->agaw);
690 	pasid_set_translation_type(pte, PASID_ENTRY_PGTT_PT);
691 	pasid_set_fault_enable(pte);
692 	pasid_set_page_snoop(pte, !!ecap_smpwc(iommu->ecap));
693 
694 	/*
695 	 * We should set SRE bit as well since the addresses are expected
696 	 * to be GPAs.
697 	 */
698 	pasid_set_sre(pte);
699 	pasid_set_present(pte);
700 	spin_unlock(&iommu->lock);
701 
702 	pasid_flush_caches(iommu, pte, pasid, did);
703 
704 	return 0;
705 }
706 
707 /*
708  * Set the page snoop control for a pasid entry which has been set up.
709  */
710 void intel_pasid_setup_page_snoop_control(struct intel_iommu *iommu,
711 					  struct device *dev, u32 pasid)
712 {
713 	struct pasid_entry *pte;
714 	u16 did;
715 
716 	spin_lock(&iommu->lock);
717 	pte = intel_pasid_get_entry(dev, pasid);
718 	if (WARN_ON(!pte || !pasid_pte_is_present(pte))) {
719 		spin_unlock(&iommu->lock);
720 		return;
721 	}
722 
723 	pasid_set_pgsnp(pte);
724 	did = pasid_get_domain_id(pte);
725 	spin_unlock(&iommu->lock);
726 
727 	if (!ecap_coherent(iommu->ecap))
728 		clflush_cache_range(pte, sizeof(*pte));
729 
730 	/*
731 	 * VT-d spec 3.4 table23 states guides for cache invalidation:
732 	 *
733 	 * - PASID-selective-within-Domain PASID-cache invalidation
734 	 * - PASID-selective PASID-based IOTLB invalidation
735 	 * - If (pasid is RID_PASID)
736 	 *    - Global Device-TLB invalidation to affected functions
737 	 *   Else
738 	 *    - PASID-based Device-TLB invalidation (with S=1 and
739 	 *      Addr[63:12]=0x7FFFFFFF_FFFFF) to affected functions
740 	 */
741 	pasid_cache_invalidation_with_pasid(iommu, did, pasid);
742 	qi_flush_piotlb(iommu, did, pasid, 0, -1, 0);
743 
744 	/* Device IOTLB doesn't need to be flushed in caching mode. */
745 	if (!cap_caching_mode(iommu->cap))
746 		devtlb_invalidation_with_pasid(iommu, dev, pasid);
747 }
748