xref: /linux/arch/x86/kvm/svm/avic.c (revision 48dea9a700c8728cc31a1dd44588b97578de86ee)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Kernel-based Virtual Machine driver for Linux
4  *
5  * AMD SVM support
6  *
7  * Copyright (C) 2006 Qumranet, Inc.
8  * Copyright 2010 Red Hat, Inc. and/or its affiliates.
9  *
10  * Authors:
11  *   Yaniv Kamay  <yaniv@qumranet.com>
12  *   Avi Kivity   <avi@qumranet.com>
13  */
14 
15 #define pr_fmt(fmt) "SVM: " fmt
16 
17 #include <linux/kvm_types.h>
18 #include <linux/hashtable.h>
19 #include <linux/amd-iommu.h>
20 #include <linux/kvm_host.h>
21 
22 #include <asm/irq_remapping.h>
23 
24 #include "trace.h"
25 #include "lapic.h"
26 #include "x86.h"
27 #include "irq.h"
28 #include "svm.h"
29 
30 /* enable / disable AVIC */
31 int avic;
32 #ifdef CONFIG_X86_LOCAL_APIC
33 module_param(avic, int, S_IRUGO);
34 #endif
35 
36 #define SVM_AVIC_DOORBELL	0xc001011b
37 
38 #define AVIC_HPA_MASK	~((0xFFFULL << 52) | 0xFFF)
39 
40 /*
41  * 0xff is broadcast, so the max index allowed for physical APIC ID
42  * table is 0xfe.  APIC IDs above 0xff are reserved.
43  */
44 #define AVIC_MAX_PHYSICAL_ID_COUNT	255
45 
46 #define AVIC_UNACCEL_ACCESS_WRITE_MASK		1
47 #define AVIC_UNACCEL_ACCESS_OFFSET_MASK		0xFF0
48 #define AVIC_UNACCEL_ACCESS_VECTOR_MASK		0xFFFFFFFF
49 
50 /* AVIC GATAG is encoded using VM and VCPU IDs */
51 #define AVIC_VCPU_ID_BITS		8
52 #define AVIC_VCPU_ID_MASK		((1 << AVIC_VCPU_ID_BITS) - 1)
53 
54 #define AVIC_VM_ID_BITS			24
55 #define AVIC_VM_ID_NR			(1 << AVIC_VM_ID_BITS)
56 #define AVIC_VM_ID_MASK			((1 << AVIC_VM_ID_BITS) - 1)
57 
58 #define AVIC_GATAG(x, y)		(((x & AVIC_VM_ID_MASK) << AVIC_VCPU_ID_BITS) | \
59 						(y & AVIC_VCPU_ID_MASK))
60 #define AVIC_GATAG_TO_VMID(x)		((x >> AVIC_VCPU_ID_BITS) & AVIC_VM_ID_MASK)
61 #define AVIC_GATAG_TO_VCPUID(x)		(x & AVIC_VCPU_ID_MASK)
62 
63 /* Note:
64  * This hash table is used to map VM_ID to a struct kvm_svm,
65  * when handling AMD IOMMU GALOG notification to schedule in
66  * a particular vCPU.
67  */
68 #define SVM_VM_DATA_HASH_BITS	8
69 static DEFINE_HASHTABLE(svm_vm_data_hash, SVM_VM_DATA_HASH_BITS);
70 static u32 next_vm_id = 0;
71 static bool next_vm_id_wrapped = 0;
72 static DEFINE_SPINLOCK(svm_vm_data_hash_lock);
73 
74 /*
75  * This is a wrapper of struct amd_iommu_ir_data.
76  */
77 struct amd_svm_iommu_ir {
78 	struct list_head node;	/* Used by SVM for per-vcpu ir_list */
79 	void *data;		/* Storing pointer to struct amd_ir_data */
80 };
81 
82 enum avic_ipi_failure_cause {
83 	AVIC_IPI_FAILURE_INVALID_INT_TYPE,
84 	AVIC_IPI_FAILURE_TARGET_NOT_RUNNING,
85 	AVIC_IPI_FAILURE_INVALID_TARGET,
86 	AVIC_IPI_FAILURE_INVALID_BACKING_PAGE,
87 };
88 
89 /* Note:
90  * This function is called from IOMMU driver to notify
91  * SVM to schedule in a particular vCPU of a particular VM.
92  */
93 int avic_ga_log_notifier(u32 ga_tag)
94 {
95 	unsigned long flags;
96 	struct kvm_svm *kvm_svm;
97 	struct kvm_vcpu *vcpu = NULL;
98 	u32 vm_id = AVIC_GATAG_TO_VMID(ga_tag);
99 	u32 vcpu_id = AVIC_GATAG_TO_VCPUID(ga_tag);
100 
101 	pr_debug("SVM: %s: vm_id=%#x, vcpu_id=%#x\n", __func__, vm_id, vcpu_id);
102 	trace_kvm_avic_ga_log(vm_id, vcpu_id);
103 
104 	spin_lock_irqsave(&svm_vm_data_hash_lock, flags);
105 	hash_for_each_possible(svm_vm_data_hash, kvm_svm, hnode, vm_id) {
106 		if (kvm_svm->avic_vm_id != vm_id)
107 			continue;
108 		vcpu = kvm_get_vcpu_by_id(&kvm_svm->kvm, vcpu_id);
109 		break;
110 	}
111 	spin_unlock_irqrestore(&svm_vm_data_hash_lock, flags);
112 
113 	/* Note:
114 	 * At this point, the IOMMU should have already set the pending
115 	 * bit in the vAPIC backing page. So, we just need to schedule
116 	 * in the vcpu.
117 	 */
118 	if (vcpu)
119 		kvm_vcpu_wake_up(vcpu);
120 
121 	return 0;
122 }
123 
124 void avic_vm_destroy(struct kvm *kvm)
125 {
126 	unsigned long flags;
127 	struct kvm_svm *kvm_svm = to_kvm_svm(kvm);
128 
129 	if (!avic)
130 		return;
131 
132 	if (kvm_svm->avic_logical_id_table_page)
133 		__free_page(kvm_svm->avic_logical_id_table_page);
134 	if (kvm_svm->avic_physical_id_table_page)
135 		__free_page(kvm_svm->avic_physical_id_table_page);
136 
137 	spin_lock_irqsave(&svm_vm_data_hash_lock, flags);
138 	hash_del(&kvm_svm->hnode);
139 	spin_unlock_irqrestore(&svm_vm_data_hash_lock, flags);
140 }
141 
142 int avic_vm_init(struct kvm *kvm)
143 {
144 	unsigned long flags;
145 	int err = -ENOMEM;
146 	struct kvm_svm *kvm_svm = to_kvm_svm(kvm);
147 	struct kvm_svm *k2;
148 	struct page *p_page;
149 	struct page *l_page;
150 	u32 vm_id;
151 
152 	if (!avic)
153 		return 0;
154 
155 	/* Allocating physical APIC ID table (4KB) */
156 	p_page = alloc_page(GFP_KERNEL_ACCOUNT);
157 	if (!p_page)
158 		goto free_avic;
159 
160 	kvm_svm->avic_physical_id_table_page = p_page;
161 	clear_page(page_address(p_page));
162 
163 	/* Allocating logical APIC ID table (4KB) */
164 	l_page = alloc_page(GFP_KERNEL_ACCOUNT);
165 	if (!l_page)
166 		goto free_avic;
167 
168 	kvm_svm->avic_logical_id_table_page = l_page;
169 	clear_page(page_address(l_page));
170 
171 	spin_lock_irqsave(&svm_vm_data_hash_lock, flags);
172  again:
173 	vm_id = next_vm_id = (next_vm_id + 1) & AVIC_VM_ID_MASK;
174 	if (vm_id == 0) { /* id is 1-based, zero is not okay */
175 		next_vm_id_wrapped = 1;
176 		goto again;
177 	}
178 	/* Is it still in use? Only possible if wrapped at least once */
179 	if (next_vm_id_wrapped) {
180 		hash_for_each_possible(svm_vm_data_hash, k2, hnode, vm_id) {
181 			if (k2->avic_vm_id == vm_id)
182 				goto again;
183 		}
184 	}
185 	kvm_svm->avic_vm_id = vm_id;
186 	hash_add(svm_vm_data_hash, &kvm_svm->hnode, kvm_svm->avic_vm_id);
187 	spin_unlock_irqrestore(&svm_vm_data_hash_lock, flags);
188 
189 	return 0;
190 
191 free_avic:
192 	avic_vm_destroy(kvm);
193 	return err;
194 }
195 
196 void avic_init_vmcb(struct vcpu_svm *svm)
197 {
198 	struct vmcb *vmcb = svm->vmcb;
199 	struct kvm_svm *kvm_svm = to_kvm_svm(svm->vcpu.kvm);
200 	phys_addr_t bpa = __sme_set(page_to_phys(svm->avic_backing_page));
201 	phys_addr_t lpa = __sme_set(page_to_phys(kvm_svm->avic_logical_id_table_page));
202 	phys_addr_t ppa = __sme_set(page_to_phys(kvm_svm->avic_physical_id_table_page));
203 
204 	vmcb->control.avic_backing_page = bpa & AVIC_HPA_MASK;
205 	vmcb->control.avic_logical_id = lpa & AVIC_HPA_MASK;
206 	vmcb->control.avic_physical_id = ppa & AVIC_HPA_MASK;
207 	vmcb->control.avic_physical_id |= AVIC_MAX_PHYSICAL_ID_COUNT;
208 	if (kvm_apicv_activated(svm->vcpu.kvm))
209 		vmcb->control.int_ctl |= AVIC_ENABLE_MASK;
210 	else
211 		vmcb->control.int_ctl &= ~AVIC_ENABLE_MASK;
212 }
213 
214 static u64 *avic_get_physical_id_entry(struct kvm_vcpu *vcpu,
215 				       unsigned int index)
216 {
217 	u64 *avic_physical_id_table;
218 	struct kvm_svm *kvm_svm = to_kvm_svm(vcpu->kvm);
219 
220 	if (index >= AVIC_MAX_PHYSICAL_ID_COUNT)
221 		return NULL;
222 
223 	avic_physical_id_table = page_address(kvm_svm->avic_physical_id_table_page);
224 
225 	return &avic_physical_id_table[index];
226 }
227 
228 /**
229  * Note:
230  * AVIC hardware walks the nested page table to check permissions,
231  * but does not use the SPA address specified in the leaf page
232  * table entry since it uses  address in the AVIC_BACKING_PAGE pointer
233  * field of the VMCB. Therefore, we set up the
234  * APIC_ACCESS_PAGE_PRIVATE_MEMSLOT (4KB) here.
235  */
236 static int avic_update_access_page(struct kvm *kvm, bool activate)
237 {
238 	int ret = 0;
239 
240 	mutex_lock(&kvm->slots_lock);
241 	/*
242 	 * During kvm_destroy_vm(), kvm_pit_set_reinject() could trigger
243 	 * APICv mode change, which update APIC_ACCESS_PAGE_PRIVATE_MEMSLOT
244 	 * memory region. So, we need to ensure that kvm->mm == current->mm.
245 	 */
246 	if ((kvm->arch.apic_access_page_done == activate) ||
247 	    (kvm->mm != current->mm))
248 		goto out;
249 
250 	ret = __x86_set_memory_region(kvm,
251 				      APIC_ACCESS_PAGE_PRIVATE_MEMSLOT,
252 				      APIC_DEFAULT_PHYS_BASE,
253 				      activate ? PAGE_SIZE : 0);
254 	if (ret)
255 		goto out;
256 
257 	kvm->arch.apic_access_page_done = activate;
258 out:
259 	mutex_unlock(&kvm->slots_lock);
260 	return ret;
261 }
262 
263 static int avic_init_backing_page(struct kvm_vcpu *vcpu)
264 {
265 	u64 *entry, new_entry;
266 	int id = vcpu->vcpu_id;
267 	struct vcpu_svm *svm = to_svm(vcpu);
268 
269 	if (id >= AVIC_MAX_PHYSICAL_ID_COUNT)
270 		return -EINVAL;
271 
272 	if (!svm->vcpu.arch.apic->regs)
273 		return -EINVAL;
274 
275 	if (kvm_apicv_activated(vcpu->kvm)) {
276 		int ret;
277 
278 		ret = avic_update_access_page(vcpu->kvm, true);
279 		if (ret)
280 			return ret;
281 	}
282 
283 	svm->avic_backing_page = virt_to_page(svm->vcpu.arch.apic->regs);
284 
285 	/* Setting AVIC backing page address in the phy APIC ID table */
286 	entry = avic_get_physical_id_entry(vcpu, id);
287 	if (!entry)
288 		return -EINVAL;
289 
290 	new_entry = __sme_set((page_to_phys(svm->avic_backing_page) &
291 			      AVIC_PHYSICAL_ID_ENTRY_BACKING_PAGE_MASK) |
292 			      AVIC_PHYSICAL_ID_ENTRY_VALID_MASK);
293 	WRITE_ONCE(*entry, new_entry);
294 
295 	svm->avic_physical_id_cache = entry;
296 
297 	return 0;
298 }
299 
300 int avic_incomplete_ipi_interception(struct vcpu_svm *svm)
301 {
302 	u32 icrh = svm->vmcb->control.exit_info_1 >> 32;
303 	u32 icrl = svm->vmcb->control.exit_info_1;
304 	u32 id = svm->vmcb->control.exit_info_2 >> 32;
305 	u32 index = svm->vmcb->control.exit_info_2 & 0xFF;
306 	struct kvm_lapic *apic = svm->vcpu.arch.apic;
307 
308 	trace_kvm_avic_incomplete_ipi(svm->vcpu.vcpu_id, icrh, icrl, id, index);
309 
310 	switch (id) {
311 	case AVIC_IPI_FAILURE_INVALID_INT_TYPE:
312 		/*
313 		 * AVIC hardware handles the generation of
314 		 * IPIs when the specified Message Type is Fixed
315 		 * (also known as fixed delivery mode) and
316 		 * the Trigger Mode is edge-triggered. The hardware
317 		 * also supports self and broadcast delivery modes
318 		 * specified via the Destination Shorthand(DSH)
319 		 * field of the ICRL. Logical and physical APIC ID
320 		 * formats are supported. All other IPI types cause
321 		 * a #VMEXIT, which needs to emulated.
322 		 */
323 		kvm_lapic_reg_write(apic, APIC_ICR2, icrh);
324 		kvm_lapic_reg_write(apic, APIC_ICR, icrl);
325 		break;
326 	case AVIC_IPI_FAILURE_TARGET_NOT_RUNNING: {
327 		int i;
328 		struct kvm_vcpu *vcpu;
329 		struct kvm *kvm = svm->vcpu.kvm;
330 		struct kvm_lapic *apic = svm->vcpu.arch.apic;
331 
332 		/*
333 		 * At this point, we expect that the AVIC HW has already
334 		 * set the appropriate IRR bits on the valid target
335 		 * vcpus. So, we just need to kick the appropriate vcpu.
336 		 */
337 		kvm_for_each_vcpu(i, vcpu, kvm) {
338 			bool m = kvm_apic_match_dest(vcpu, apic,
339 						     icrl & APIC_SHORT_MASK,
340 						     GET_APIC_DEST_FIELD(icrh),
341 						     icrl & APIC_DEST_MASK);
342 
343 			if (m && !avic_vcpu_is_running(vcpu))
344 				kvm_vcpu_wake_up(vcpu);
345 		}
346 		break;
347 	}
348 	case AVIC_IPI_FAILURE_INVALID_TARGET:
349 		WARN_ONCE(1, "Invalid IPI target: index=%u, vcpu=%d, icr=%#0x:%#0x\n",
350 			  index, svm->vcpu.vcpu_id, icrh, icrl);
351 		break;
352 	case AVIC_IPI_FAILURE_INVALID_BACKING_PAGE:
353 		WARN_ONCE(1, "Invalid backing page\n");
354 		break;
355 	default:
356 		pr_err("Unknown IPI interception\n");
357 	}
358 
359 	return 1;
360 }
361 
362 static u32 *avic_get_logical_id_entry(struct kvm_vcpu *vcpu, u32 ldr, bool flat)
363 {
364 	struct kvm_svm *kvm_svm = to_kvm_svm(vcpu->kvm);
365 	int index;
366 	u32 *logical_apic_id_table;
367 	int dlid = GET_APIC_LOGICAL_ID(ldr);
368 
369 	if (!dlid)
370 		return NULL;
371 
372 	if (flat) { /* flat */
373 		index = ffs(dlid) - 1;
374 		if (index > 7)
375 			return NULL;
376 	} else { /* cluster */
377 		int cluster = (dlid & 0xf0) >> 4;
378 		int apic = ffs(dlid & 0x0f) - 1;
379 
380 		if ((apic < 0) || (apic > 7) ||
381 		    (cluster >= 0xf))
382 			return NULL;
383 		index = (cluster << 2) + apic;
384 	}
385 
386 	logical_apic_id_table = (u32 *) page_address(kvm_svm->avic_logical_id_table_page);
387 
388 	return &logical_apic_id_table[index];
389 }
390 
391 static int avic_ldr_write(struct kvm_vcpu *vcpu, u8 g_physical_id, u32 ldr)
392 {
393 	bool flat;
394 	u32 *entry, new_entry;
395 
396 	flat = kvm_lapic_get_reg(vcpu->arch.apic, APIC_DFR) == APIC_DFR_FLAT;
397 	entry = avic_get_logical_id_entry(vcpu, ldr, flat);
398 	if (!entry)
399 		return -EINVAL;
400 
401 	new_entry = READ_ONCE(*entry);
402 	new_entry &= ~AVIC_LOGICAL_ID_ENTRY_GUEST_PHYSICAL_ID_MASK;
403 	new_entry |= (g_physical_id & AVIC_LOGICAL_ID_ENTRY_GUEST_PHYSICAL_ID_MASK);
404 	new_entry |= AVIC_LOGICAL_ID_ENTRY_VALID_MASK;
405 	WRITE_ONCE(*entry, new_entry);
406 
407 	return 0;
408 }
409 
410 static void avic_invalidate_logical_id_entry(struct kvm_vcpu *vcpu)
411 {
412 	struct vcpu_svm *svm = to_svm(vcpu);
413 	bool flat = svm->dfr_reg == APIC_DFR_FLAT;
414 	u32 *entry = avic_get_logical_id_entry(vcpu, svm->ldr_reg, flat);
415 
416 	if (entry)
417 		clear_bit(AVIC_LOGICAL_ID_ENTRY_VALID_BIT, (unsigned long *)entry);
418 }
419 
420 static int avic_handle_ldr_update(struct kvm_vcpu *vcpu)
421 {
422 	int ret = 0;
423 	struct vcpu_svm *svm = to_svm(vcpu);
424 	u32 ldr = kvm_lapic_get_reg(vcpu->arch.apic, APIC_LDR);
425 	u32 id = kvm_xapic_id(vcpu->arch.apic);
426 
427 	if (ldr == svm->ldr_reg)
428 		return 0;
429 
430 	avic_invalidate_logical_id_entry(vcpu);
431 
432 	if (ldr)
433 		ret = avic_ldr_write(vcpu, id, ldr);
434 
435 	if (!ret)
436 		svm->ldr_reg = ldr;
437 
438 	return ret;
439 }
440 
441 static int avic_handle_apic_id_update(struct kvm_vcpu *vcpu)
442 {
443 	u64 *old, *new;
444 	struct vcpu_svm *svm = to_svm(vcpu);
445 	u32 id = kvm_xapic_id(vcpu->arch.apic);
446 
447 	if (vcpu->vcpu_id == id)
448 		return 0;
449 
450 	old = avic_get_physical_id_entry(vcpu, vcpu->vcpu_id);
451 	new = avic_get_physical_id_entry(vcpu, id);
452 	if (!new || !old)
453 		return 1;
454 
455 	/* We need to move physical_id_entry to new offset */
456 	*new = *old;
457 	*old = 0ULL;
458 	to_svm(vcpu)->avic_physical_id_cache = new;
459 
460 	/*
461 	 * Also update the guest physical APIC ID in the logical
462 	 * APIC ID table entry if already setup the LDR.
463 	 */
464 	if (svm->ldr_reg)
465 		avic_handle_ldr_update(vcpu);
466 
467 	return 0;
468 }
469 
470 static void avic_handle_dfr_update(struct kvm_vcpu *vcpu)
471 {
472 	struct vcpu_svm *svm = to_svm(vcpu);
473 	u32 dfr = kvm_lapic_get_reg(vcpu->arch.apic, APIC_DFR);
474 
475 	if (svm->dfr_reg == dfr)
476 		return;
477 
478 	avic_invalidate_logical_id_entry(vcpu);
479 	svm->dfr_reg = dfr;
480 }
481 
482 static int avic_unaccel_trap_write(struct vcpu_svm *svm)
483 {
484 	struct kvm_lapic *apic = svm->vcpu.arch.apic;
485 	u32 offset = svm->vmcb->control.exit_info_1 &
486 				AVIC_UNACCEL_ACCESS_OFFSET_MASK;
487 
488 	switch (offset) {
489 	case APIC_ID:
490 		if (avic_handle_apic_id_update(&svm->vcpu))
491 			return 0;
492 		break;
493 	case APIC_LDR:
494 		if (avic_handle_ldr_update(&svm->vcpu))
495 			return 0;
496 		break;
497 	case APIC_DFR:
498 		avic_handle_dfr_update(&svm->vcpu);
499 		break;
500 	default:
501 		break;
502 	}
503 
504 	kvm_lapic_reg_write(apic, offset, kvm_lapic_get_reg(apic, offset));
505 
506 	return 1;
507 }
508 
509 static bool is_avic_unaccelerated_access_trap(u32 offset)
510 {
511 	bool ret = false;
512 
513 	switch (offset) {
514 	case APIC_ID:
515 	case APIC_EOI:
516 	case APIC_RRR:
517 	case APIC_LDR:
518 	case APIC_DFR:
519 	case APIC_SPIV:
520 	case APIC_ESR:
521 	case APIC_ICR:
522 	case APIC_LVTT:
523 	case APIC_LVTTHMR:
524 	case APIC_LVTPC:
525 	case APIC_LVT0:
526 	case APIC_LVT1:
527 	case APIC_LVTERR:
528 	case APIC_TMICT:
529 	case APIC_TDCR:
530 		ret = true;
531 		break;
532 	default:
533 		break;
534 	}
535 	return ret;
536 }
537 
538 int avic_unaccelerated_access_interception(struct vcpu_svm *svm)
539 {
540 	int ret = 0;
541 	u32 offset = svm->vmcb->control.exit_info_1 &
542 		     AVIC_UNACCEL_ACCESS_OFFSET_MASK;
543 	u32 vector = svm->vmcb->control.exit_info_2 &
544 		     AVIC_UNACCEL_ACCESS_VECTOR_MASK;
545 	bool write = (svm->vmcb->control.exit_info_1 >> 32) &
546 		     AVIC_UNACCEL_ACCESS_WRITE_MASK;
547 	bool trap = is_avic_unaccelerated_access_trap(offset);
548 
549 	trace_kvm_avic_unaccelerated_access(svm->vcpu.vcpu_id, offset,
550 					    trap, write, vector);
551 	if (trap) {
552 		/* Handling Trap */
553 		WARN_ONCE(!write, "svm: Handling trap read.\n");
554 		ret = avic_unaccel_trap_write(svm);
555 	} else {
556 		/* Handling Fault */
557 		ret = kvm_emulate_instruction(&svm->vcpu, 0);
558 	}
559 
560 	return ret;
561 }
562 
563 int avic_init_vcpu(struct vcpu_svm *svm)
564 {
565 	int ret;
566 	struct kvm_vcpu *vcpu = &svm->vcpu;
567 
568 	if (!avic || !irqchip_in_kernel(vcpu->kvm))
569 		return 0;
570 
571 	ret = avic_init_backing_page(&svm->vcpu);
572 	if (ret)
573 		return ret;
574 
575 	INIT_LIST_HEAD(&svm->ir_list);
576 	spin_lock_init(&svm->ir_list_lock);
577 	svm->dfr_reg = APIC_DFR_FLAT;
578 
579 	return ret;
580 }
581 
582 void avic_post_state_restore(struct kvm_vcpu *vcpu)
583 {
584 	if (avic_handle_apic_id_update(vcpu) != 0)
585 		return;
586 	avic_handle_dfr_update(vcpu);
587 	avic_handle_ldr_update(vcpu);
588 }
589 
590 void svm_toggle_avic_for_irq_window(struct kvm_vcpu *vcpu, bool activate)
591 {
592 	if (!avic || !lapic_in_kernel(vcpu))
593 		return;
594 
595 	srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx);
596 	kvm_request_apicv_update(vcpu->kvm, activate,
597 				 APICV_INHIBIT_REASON_IRQWIN);
598 	vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);
599 }
600 
601 void svm_set_virtual_apic_mode(struct kvm_vcpu *vcpu)
602 {
603 	return;
604 }
605 
606 void svm_hwapic_irr_update(struct kvm_vcpu *vcpu, int max_irr)
607 {
608 }
609 
610 void svm_hwapic_isr_update(struct kvm_vcpu *vcpu, int max_isr)
611 {
612 }
613 
614 static int svm_set_pi_irte_mode(struct kvm_vcpu *vcpu, bool activate)
615 {
616 	int ret = 0;
617 	unsigned long flags;
618 	struct amd_svm_iommu_ir *ir;
619 	struct vcpu_svm *svm = to_svm(vcpu);
620 
621 	if (!kvm_arch_has_assigned_device(vcpu->kvm))
622 		return 0;
623 
624 	/*
625 	 * Here, we go through the per-vcpu ir_list to update all existing
626 	 * interrupt remapping table entry targeting this vcpu.
627 	 */
628 	spin_lock_irqsave(&svm->ir_list_lock, flags);
629 
630 	if (list_empty(&svm->ir_list))
631 		goto out;
632 
633 	list_for_each_entry(ir, &svm->ir_list, node) {
634 		if (activate)
635 			ret = amd_iommu_activate_guest_mode(ir->data);
636 		else
637 			ret = amd_iommu_deactivate_guest_mode(ir->data);
638 		if (ret)
639 			break;
640 	}
641 out:
642 	spin_unlock_irqrestore(&svm->ir_list_lock, flags);
643 	return ret;
644 }
645 
646 void svm_refresh_apicv_exec_ctrl(struct kvm_vcpu *vcpu)
647 {
648 	struct vcpu_svm *svm = to_svm(vcpu);
649 	struct vmcb *vmcb = svm->vmcb;
650 	bool activated = kvm_vcpu_apicv_active(vcpu);
651 
652 	if (!avic)
653 		return;
654 
655 	if (activated) {
656 		/**
657 		 * During AVIC temporary deactivation, guest could update
658 		 * APIC ID, DFR and LDR registers, which would not be trapped
659 		 * by avic_unaccelerated_access_interception(). In this case,
660 		 * we need to check and update the AVIC logical APIC ID table
661 		 * accordingly before re-activating.
662 		 */
663 		avic_post_state_restore(vcpu);
664 		vmcb->control.int_ctl |= AVIC_ENABLE_MASK;
665 	} else {
666 		vmcb->control.int_ctl &= ~AVIC_ENABLE_MASK;
667 	}
668 	vmcb_mark_dirty(vmcb, VMCB_AVIC);
669 
670 	svm_set_pi_irte_mode(vcpu, activated);
671 }
672 
673 void svm_load_eoi_exitmap(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap)
674 {
675 	return;
676 }
677 
678 int svm_deliver_avic_intr(struct kvm_vcpu *vcpu, int vec)
679 {
680 	if (!vcpu->arch.apicv_active)
681 		return -1;
682 
683 	kvm_lapic_set_irr(vec, vcpu->arch.apic);
684 	smp_mb__after_atomic();
685 
686 	if (avic_vcpu_is_running(vcpu)) {
687 		int cpuid = vcpu->cpu;
688 
689 		if (cpuid != get_cpu())
690 			wrmsrl(SVM_AVIC_DOORBELL, kvm_cpu_get_apicid(cpuid));
691 		put_cpu();
692 	} else
693 		kvm_vcpu_wake_up(vcpu);
694 
695 	return 0;
696 }
697 
698 bool svm_dy_apicv_has_pending_interrupt(struct kvm_vcpu *vcpu)
699 {
700 	return false;
701 }
702 
703 static void svm_ir_list_del(struct vcpu_svm *svm, struct amd_iommu_pi_data *pi)
704 {
705 	unsigned long flags;
706 	struct amd_svm_iommu_ir *cur;
707 
708 	spin_lock_irqsave(&svm->ir_list_lock, flags);
709 	list_for_each_entry(cur, &svm->ir_list, node) {
710 		if (cur->data != pi->ir_data)
711 			continue;
712 		list_del(&cur->node);
713 		kfree(cur);
714 		break;
715 	}
716 	spin_unlock_irqrestore(&svm->ir_list_lock, flags);
717 }
718 
719 static int svm_ir_list_add(struct vcpu_svm *svm, struct amd_iommu_pi_data *pi)
720 {
721 	int ret = 0;
722 	unsigned long flags;
723 	struct amd_svm_iommu_ir *ir;
724 
725 	/**
726 	 * In some cases, the existing irte is updaed and re-set,
727 	 * so we need to check here if it's already been * added
728 	 * to the ir_list.
729 	 */
730 	if (pi->ir_data && (pi->prev_ga_tag != 0)) {
731 		struct kvm *kvm = svm->vcpu.kvm;
732 		u32 vcpu_id = AVIC_GATAG_TO_VCPUID(pi->prev_ga_tag);
733 		struct kvm_vcpu *prev_vcpu = kvm_get_vcpu_by_id(kvm, vcpu_id);
734 		struct vcpu_svm *prev_svm;
735 
736 		if (!prev_vcpu) {
737 			ret = -EINVAL;
738 			goto out;
739 		}
740 
741 		prev_svm = to_svm(prev_vcpu);
742 		svm_ir_list_del(prev_svm, pi);
743 	}
744 
745 	/**
746 	 * Allocating new amd_iommu_pi_data, which will get
747 	 * add to the per-vcpu ir_list.
748 	 */
749 	ir = kzalloc(sizeof(struct amd_svm_iommu_ir), GFP_KERNEL_ACCOUNT);
750 	if (!ir) {
751 		ret = -ENOMEM;
752 		goto out;
753 	}
754 	ir->data = pi->ir_data;
755 
756 	spin_lock_irqsave(&svm->ir_list_lock, flags);
757 	list_add(&ir->node, &svm->ir_list);
758 	spin_unlock_irqrestore(&svm->ir_list_lock, flags);
759 out:
760 	return ret;
761 }
762 
763 /**
764  * Note:
765  * The HW cannot support posting multicast/broadcast
766  * interrupts to a vCPU. So, we still use legacy interrupt
767  * remapping for these kind of interrupts.
768  *
769  * For lowest-priority interrupts, we only support
770  * those with single CPU as the destination, e.g. user
771  * configures the interrupts via /proc/irq or uses
772  * irqbalance to make the interrupts single-CPU.
773  */
774 static int
775 get_pi_vcpu_info(struct kvm *kvm, struct kvm_kernel_irq_routing_entry *e,
776 		 struct vcpu_data *vcpu_info, struct vcpu_svm **svm)
777 {
778 	struct kvm_lapic_irq irq;
779 	struct kvm_vcpu *vcpu = NULL;
780 
781 	kvm_set_msi_irq(kvm, e, &irq);
782 
783 	if (!kvm_intr_is_single_vcpu(kvm, &irq, &vcpu) ||
784 	    !kvm_irq_is_postable(&irq)) {
785 		pr_debug("SVM: %s: use legacy intr remap mode for irq %u\n",
786 			 __func__, irq.vector);
787 		return -1;
788 	}
789 
790 	pr_debug("SVM: %s: use GA mode for irq %u\n", __func__,
791 		 irq.vector);
792 	*svm = to_svm(vcpu);
793 	vcpu_info->pi_desc_addr = __sme_set(page_to_phys((*svm)->avic_backing_page));
794 	vcpu_info->vector = irq.vector;
795 
796 	return 0;
797 }
798 
799 /*
800  * svm_update_pi_irte - set IRTE for Posted-Interrupts
801  *
802  * @kvm: kvm
803  * @host_irq: host irq of the interrupt
804  * @guest_irq: gsi of the interrupt
805  * @set: set or unset PI
806  * returns 0 on success, < 0 on failure
807  */
808 int svm_update_pi_irte(struct kvm *kvm, unsigned int host_irq,
809 		       uint32_t guest_irq, bool set)
810 {
811 	struct kvm_kernel_irq_routing_entry *e;
812 	struct kvm_irq_routing_table *irq_rt;
813 	int idx, ret = -EINVAL;
814 
815 	if (!kvm_arch_has_assigned_device(kvm) ||
816 	    !irq_remapping_cap(IRQ_POSTING_CAP))
817 		return 0;
818 
819 	pr_debug("SVM: %s: host_irq=%#x, guest_irq=%#x, set=%#x\n",
820 		 __func__, host_irq, guest_irq, set);
821 
822 	idx = srcu_read_lock(&kvm->irq_srcu);
823 	irq_rt = srcu_dereference(kvm->irq_routing, &kvm->irq_srcu);
824 	WARN_ON(guest_irq >= irq_rt->nr_rt_entries);
825 
826 	hlist_for_each_entry(e, &irq_rt->map[guest_irq], link) {
827 		struct vcpu_data vcpu_info;
828 		struct vcpu_svm *svm = NULL;
829 
830 		if (e->type != KVM_IRQ_ROUTING_MSI)
831 			continue;
832 
833 		/**
834 		 * Here, we setup with legacy mode in the following cases:
835 		 * 1. When cannot target interrupt to a specific vcpu.
836 		 * 2. Unsetting posted interrupt.
837 		 * 3. APIC virtialization is disabled for the vcpu.
838 		 * 4. IRQ has incompatible delivery mode (SMI, INIT, etc)
839 		 */
840 		if (!get_pi_vcpu_info(kvm, e, &vcpu_info, &svm) && set &&
841 		    kvm_vcpu_apicv_active(&svm->vcpu)) {
842 			struct amd_iommu_pi_data pi;
843 
844 			/* Try to enable guest_mode in IRTE */
845 			pi.base = __sme_set(page_to_phys(svm->avic_backing_page) &
846 					    AVIC_HPA_MASK);
847 			pi.ga_tag = AVIC_GATAG(to_kvm_svm(kvm)->avic_vm_id,
848 						     svm->vcpu.vcpu_id);
849 			pi.is_guest_mode = true;
850 			pi.vcpu_data = &vcpu_info;
851 			ret = irq_set_vcpu_affinity(host_irq, &pi);
852 
853 			/**
854 			 * Here, we successfully setting up vcpu affinity in
855 			 * IOMMU guest mode. Now, we need to store the posted
856 			 * interrupt information in a per-vcpu ir_list so that
857 			 * we can reference to them directly when we update vcpu
858 			 * scheduling information in IOMMU irte.
859 			 */
860 			if (!ret && pi.is_guest_mode)
861 				svm_ir_list_add(svm, &pi);
862 		} else {
863 			/* Use legacy mode in IRTE */
864 			struct amd_iommu_pi_data pi;
865 
866 			/**
867 			 * Here, pi is used to:
868 			 * - Tell IOMMU to use legacy mode for this interrupt.
869 			 * - Retrieve ga_tag of prior interrupt remapping data.
870 			 */
871 			pi.is_guest_mode = false;
872 			ret = irq_set_vcpu_affinity(host_irq, &pi);
873 
874 			/**
875 			 * Check if the posted interrupt was previously
876 			 * setup with the guest_mode by checking if the ga_tag
877 			 * was cached. If so, we need to clean up the per-vcpu
878 			 * ir_list.
879 			 */
880 			if (!ret && pi.prev_ga_tag) {
881 				int id = AVIC_GATAG_TO_VCPUID(pi.prev_ga_tag);
882 				struct kvm_vcpu *vcpu;
883 
884 				vcpu = kvm_get_vcpu_by_id(kvm, id);
885 				if (vcpu)
886 					svm_ir_list_del(to_svm(vcpu), &pi);
887 			}
888 		}
889 
890 		if (!ret && svm) {
891 			trace_kvm_pi_irte_update(host_irq, svm->vcpu.vcpu_id,
892 						 e->gsi, vcpu_info.vector,
893 						 vcpu_info.pi_desc_addr, set);
894 		}
895 
896 		if (ret < 0) {
897 			pr_err("%s: failed to update PI IRTE\n", __func__);
898 			goto out;
899 		}
900 	}
901 
902 	ret = 0;
903 out:
904 	srcu_read_unlock(&kvm->irq_srcu, idx);
905 	return ret;
906 }
907 
908 bool svm_check_apicv_inhibit_reasons(ulong bit)
909 {
910 	ulong supported = BIT(APICV_INHIBIT_REASON_DISABLE) |
911 			  BIT(APICV_INHIBIT_REASON_HYPERV) |
912 			  BIT(APICV_INHIBIT_REASON_NESTED) |
913 			  BIT(APICV_INHIBIT_REASON_IRQWIN) |
914 			  BIT(APICV_INHIBIT_REASON_PIT_REINJ) |
915 			  BIT(APICV_INHIBIT_REASON_X2APIC);
916 
917 	return supported & BIT(bit);
918 }
919 
920 void svm_pre_update_apicv_exec_ctrl(struct kvm *kvm, bool activate)
921 {
922 	avic_update_access_page(kvm, activate);
923 }
924 
925 static inline int
926 avic_update_iommu_vcpu_affinity(struct kvm_vcpu *vcpu, int cpu, bool r)
927 {
928 	int ret = 0;
929 	unsigned long flags;
930 	struct amd_svm_iommu_ir *ir;
931 	struct vcpu_svm *svm = to_svm(vcpu);
932 
933 	if (!kvm_arch_has_assigned_device(vcpu->kvm))
934 		return 0;
935 
936 	/*
937 	 * Here, we go through the per-vcpu ir_list to update all existing
938 	 * interrupt remapping table entry targeting this vcpu.
939 	 */
940 	spin_lock_irqsave(&svm->ir_list_lock, flags);
941 
942 	if (list_empty(&svm->ir_list))
943 		goto out;
944 
945 	list_for_each_entry(ir, &svm->ir_list, node) {
946 		ret = amd_iommu_update_ga(cpu, r, ir->data);
947 		if (ret)
948 			break;
949 	}
950 out:
951 	spin_unlock_irqrestore(&svm->ir_list_lock, flags);
952 	return ret;
953 }
954 
955 void avic_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
956 {
957 	u64 entry;
958 	/* ID = 0xff (broadcast), ID > 0xff (reserved) */
959 	int h_physical_id = kvm_cpu_get_apicid(cpu);
960 	struct vcpu_svm *svm = to_svm(vcpu);
961 
962 	if (!kvm_vcpu_apicv_active(vcpu))
963 		return;
964 
965 	/*
966 	 * Since the host physical APIC id is 8 bits,
967 	 * we can support host APIC ID upto 255.
968 	 */
969 	if (WARN_ON(h_physical_id > AVIC_PHYSICAL_ID_ENTRY_HOST_PHYSICAL_ID_MASK))
970 		return;
971 
972 	entry = READ_ONCE(*(svm->avic_physical_id_cache));
973 	WARN_ON(entry & AVIC_PHYSICAL_ID_ENTRY_IS_RUNNING_MASK);
974 
975 	entry &= ~AVIC_PHYSICAL_ID_ENTRY_HOST_PHYSICAL_ID_MASK;
976 	entry |= (h_physical_id & AVIC_PHYSICAL_ID_ENTRY_HOST_PHYSICAL_ID_MASK);
977 
978 	entry &= ~AVIC_PHYSICAL_ID_ENTRY_IS_RUNNING_MASK;
979 	if (svm->avic_is_running)
980 		entry |= AVIC_PHYSICAL_ID_ENTRY_IS_RUNNING_MASK;
981 
982 	WRITE_ONCE(*(svm->avic_physical_id_cache), entry);
983 	avic_update_iommu_vcpu_affinity(vcpu, h_physical_id,
984 					svm->avic_is_running);
985 }
986 
987 void avic_vcpu_put(struct kvm_vcpu *vcpu)
988 {
989 	u64 entry;
990 	struct vcpu_svm *svm = to_svm(vcpu);
991 
992 	if (!kvm_vcpu_apicv_active(vcpu))
993 		return;
994 
995 	entry = READ_ONCE(*(svm->avic_physical_id_cache));
996 	if (entry & AVIC_PHYSICAL_ID_ENTRY_IS_RUNNING_MASK)
997 		avic_update_iommu_vcpu_affinity(vcpu, -1, 0);
998 
999 	entry &= ~AVIC_PHYSICAL_ID_ENTRY_IS_RUNNING_MASK;
1000 	WRITE_ONCE(*(svm->avic_physical_id_cache), entry);
1001 }
1002 
1003 /**
1004  * This function is called during VCPU halt/unhalt.
1005  */
1006 static void avic_set_running(struct kvm_vcpu *vcpu, bool is_run)
1007 {
1008 	struct vcpu_svm *svm = to_svm(vcpu);
1009 
1010 	svm->avic_is_running = is_run;
1011 	if (is_run)
1012 		avic_vcpu_load(vcpu, vcpu->cpu);
1013 	else
1014 		avic_vcpu_put(vcpu);
1015 }
1016 
1017 void svm_vcpu_blocking(struct kvm_vcpu *vcpu)
1018 {
1019 	avic_set_running(vcpu, false);
1020 }
1021 
1022 void svm_vcpu_unblocking(struct kvm_vcpu *vcpu)
1023 {
1024 	if (kvm_check_request(KVM_REQ_APICV_UPDATE, vcpu))
1025 		kvm_vcpu_update_apicv(vcpu);
1026 	avic_set_running(vcpu, true);
1027 }
1028