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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright © 2019 Oracle and/or its affiliates. All rights reserved.
4 * Copyright © 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved.
5 *
6 * KVM Xen emulation
7 */
8
9#include "x86.h"
10#include "xen.h"
11#include "hyperv.h"
12
13#include <linux/kvm_host.h>
14#include <linux/sched/stat.h>
15
16#include <trace/events/kvm.h>
17#include <xen/interface/xen.h>
18#include <xen/interface/vcpu.h>
19
20#include "trace.h"
21
22DEFINE_STATIC_KEY_DEFERRED_FALSE(kvm_xen_enabled, HZ);
23
24static int kvm_xen_shared_info_init(struct kvm *kvm, gfn_t gfn)
25{
26 gpa_t gpa = gfn_to_gpa(gfn);
27 int wc_ofs, sec_hi_ofs;
28 int ret;
29 int idx = srcu_read_lock(&kvm->srcu);
30
31 ret = kvm_gfn_to_hva_cache_init(kvm, &kvm->arch.xen.shinfo_cache,
32 gpa, PAGE_SIZE);
33 if (ret)
34 goto out;
35
36 kvm->arch.xen.shinfo_set = true;
37
38 /* Paranoia checks on the 32-bit struct layout */
39 BUILD_BUG_ON(offsetof(struct compat_shared_info, wc) != 0x900);
40 BUILD_BUG_ON(offsetof(struct compat_shared_info, arch.wc_sec_hi) != 0x924);
41 BUILD_BUG_ON(offsetof(struct pvclock_vcpu_time_info, version) != 0);
42
43 /* 32-bit location by default */
44 wc_ofs = offsetof(struct compat_shared_info, wc);
45 sec_hi_ofs = offsetof(struct compat_shared_info, arch.wc_sec_hi);
46
47#ifdef CONFIG_X86_64
48 /* Paranoia checks on the 64-bit struct layout */
49 BUILD_BUG_ON(offsetof(struct shared_info, wc) != 0xc00);
50 BUILD_BUG_ON(offsetof(struct shared_info, wc_sec_hi) != 0xc0c);
51
52 if (kvm->arch.xen.long_mode) {
53 wc_ofs = offsetof(struct shared_info, wc);
54 sec_hi_ofs = offsetof(struct shared_info, wc_sec_hi);
55 }
56#endif
57
58 kvm_write_wall_clock(kvm, gpa + wc_ofs, sec_hi_ofs - wc_ofs);
59 kvm_make_all_cpus_request(kvm, KVM_REQ_MASTERCLOCK_UPDATE);
60
61out:
62 srcu_read_unlock(&kvm->srcu, idx);
63 return ret;
64}
65
66static void kvm_xen_update_runstate(struct kvm_vcpu *v, int state)
67{
68 struct kvm_vcpu_xen *vx = &v->arch.xen;
69 u64 now = get_kvmclock_ns(v->kvm);
70 u64 delta_ns = now - vx->runstate_entry_time;
71 u64 run_delay = current->sched_info.run_delay;
72
73 if (unlikely(!vx->runstate_entry_time))
74 vx->current_runstate = RUNSTATE_offline;
75
76 /*
77 * Time waiting for the scheduler isn't "stolen" if the
78 * vCPU wasn't running anyway.
79 */
80 if (vx->current_runstate == RUNSTATE_running) {
81 u64 steal_ns = run_delay - vx->last_steal;
82
83 delta_ns -= steal_ns;
84
85 vx->runstate_times[RUNSTATE_runnable] += steal_ns;
86 }
87 vx->last_steal = run_delay;
88
89 vx->runstate_times[vx->current_runstate] += delta_ns;
90 vx->current_runstate = state;
91 vx->runstate_entry_time = now;
92}
93
94void kvm_xen_update_runstate_guest(struct kvm_vcpu *v, int state)
95{
96 struct kvm_vcpu_xen *vx = &v->arch.xen;
97 uint64_t state_entry_time;
98 unsigned int offset;
99
100 kvm_xen_update_runstate(v, state);
101
102 if (!vx->runstate_set)
103 return;
104
105 BUILD_BUG_ON(sizeof(struct compat_vcpu_runstate_info) != 0x2c);
106
107 offset = offsetof(struct compat_vcpu_runstate_info, state_entry_time);
108#ifdef CONFIG_X86_64
109 /*
110 * The only difference is alignment of uint64_t in 32-bit.
111 * So the first field 'state' is accessed directly using
112 * offsetof() (where its offset happens to be zero), while the
113 * remaining fields which are all uint64_t, start at 'offset'
114 * which we tweak here by adding 4.
115 */
116 BUILD_BUG_ON(offsetof(struct vcpu_runstate_info, state_entry_time) !=
117 offsetof(struct compat_vcpu_runstate_info, state_entry_time) + 4);
118 BUILD_BUG_ON(offsetof(struct vcpu_runstate_info, time) !=
119 offsetof(struct compat_vcpu_runstate_info, time) + 4);
120
121 if (v->kvm->arch.xen.long_mode)
122 offset = offsetof(struct vcpu_runstate_info, state_entry_time);
123#endif
124 /*
125 * First write the updated state_entry_time at the appropriate
126 * location determined by 'offset'.
127 */
128 state_entry_time = vx->runstate_entry_time;
129 state_entry_time |= XEN_RUNSTATE_UPDATE;
130
131 BUILD_BUG_ON(sizeof(((struct vcpu_runstate_info *)0)->state_entry_time) !=
132 sizeof(state_entry_time));
133 BUILD_BUG_ON(sizeof(((struct compat_vcpu_runstate_info *)0)->state_entry_time) !=
134 sizeof(state_entry_time));
135
136 if (kvm_write_guest_offset_cached(v->kvm, &v->arch.xen.runstate_cache,
137 &state_entry_time, offset,
138 sizeof(state_entry_time)))
139 return;
140 smp_wmb();
141
142 /*
143 * Next, write the new runstate. This is in the *same* place
144 * for 32-bit and 64-bit guests, asserted here for paranoia.
145 */
146 BUILD_BUG_ON(offsetof(struct vcpu_runstate_info, state) !=
147 offsetof(struct compat_vcpu_runstate_info, state));
148 BUILD_BUG_ON(sizeof(((struct vcpu_runstate_info *)0)->state) !=
149 sizeof(vx->current_runstate));
150 BUILD_BUG_ON(sizeof(((struct compat_vcpu_runstate_info *)0)->state) !=
151 sizeof(vx->current_runstate));
152
153 if (kvm_write_guest_offset_cached(v->kvm, &v->arch.xen.runstate_cache,
154 &vx->current_runstate,
155 offsetof(struct vcpu_runstate_info, state),
156 sizeof(vx->current_runstate)))
157 return;
158
159 /*
160 * Write the actual runstate times immediately after the
161 * runstate_entry_time.
162 */
163 BUILD_BUG_ON(offsetof(struct vcpu_runstate_info, state_entry_time) !=
164 offsetof(struct vcpu_runstate_info, time) - sizeof(u64));
165 BUILD_BUG_ON(offsetof(struct compat_vcpu_runstate_info, state_entry_time) !=
166 offsetof(struct compat_vcpu_runstate_info, time) - sizeof(u64));
167 BUILD_BUG_ON(sizeof(((struct vcpu_runstate_info *)0)->time) !=
168 sizeof(((struct compat_vcpu_runstate_info *)0)->time));
169 BUILD_BUG_ON(sizeof(((struct vcpu_runstate_info *)0)->time) !=
170 sizeof(vx->runstate_times));
171
172 if (kvm_write_guest_offset_cached(v->kvm, &v->arch.xen.runstate_cache,
173 &vx->runstate_times[0],
174 offset + sizeof(u64),
175 sizeof(vx->runstate_times)))
176 return;
177
178 smp_wmb();
179
180 /*
181 * Finally, clear the XEN_RUNSTATE_UPDATE bit in the guest's
182 * runstate_entry_time field.
183 */
184
185 state_entry_time &= ~XEN_RUNSTATE_UPDATE;
186 if (kvm_write_guest_offset_cached(v->kvm, &v->arch.xen.runstate_cache,
187 &state_entry_time, offset,
188 sizeof(state_entry_time)))
189 return;
190}
191
192int __kvm_xen_has_interrupt(struct kvm_vcpu *v)
193{
194 u8 rc = 0;
195
196 /*
197 * If the global upcall vector (HVMIRQ_callback_vector) is set and
198 * the vCPU's evtchn_upcall_pending flag is set, the IRQ is pending.
199 */
200 struct gfn_to_hva_cache *ghc = &v->arch.xen.vcpu_info_cache;
201 struct kvm_memslots *slots = kvm_memslots(v->kvm);
202 unsigned int offset = offsetof(struct vcpu_info, evtchn_upcall_pending);
203
204 /* No need for compat handling here */
205 BUILD_BUG_ON(offsetof(struct vcpu_info, evtchn_upcall_pending) !=
206 offsetof(struct compat_vcpu_info, evtchn_upcall_pending));
207 BUILD_BUG_ON(sizeof(rc) !=
208 sizeof(((struct vcpu_info *)0)->evtchn_upcall_pending));
209 BUILD_BUG_ON(sizeof(rc) !=
210 sizeof(((struct compat_vcpu_info *)0)->evtchn_upcall_pending));
211
212 /*
213 * For efficiency, this mirrors the checks for using the valid
214 * cache in kvm_read_guest_offset_cached(), but just uses
215 * __get_user() instead. And falls back to the slow path.
216 */
217 if (likely(slots->generation == ghc->generation &&
218 !kvm_is_error_hva(ghc->hva) && ghc->memslot)) {
219 /* Fast path */
220 __get_user(rc, (u8 __user *)ghc->hva + offset);
221 } else {
222 /* Slow path */
223 kvm_read_guest_offset_cached(v->kvm, ghc, &rc, offset,
224 sizeof(rc));
225 }
226
227 return rc;
228}
229
230int kvm_xen_hvm_set_attr(struct kvm *kvm, struct kvm_xen_hvm_attr *data)
231{
232 int r = -ENOENT;
233
234 mutex_lock(&kvm->lock);
235
236 switch (data->type) {
237 case KVM_XEN_ATTR_TYPE_LONG_MODE:
238 if (!IS_ENABLED(CONFIG_64BIT) && data->u.long_mode) {
239 r = -EINVAL;
240 } else {
241 kvm->arch.xen.long_mode = !!data->u.long_mode;
242 r = 0;
243 }
244 break;
245
246 case KVM_XEN_ATTR_TYPE_SHARED_INFO:
247 if (data->u.shared_info.gfn == GPA_INVALID) {
248 kvm->arch.xen.shinfo_set = false;
249 r = 0;
250 break;
251 }
252 r = kvm_xen_shared_info_init(kvm, data->u.shared_info.gfn);
253 break;
254
255
256 case KVM_XEN_ATTR_TYPE_UPCALL_VECTOR:
257 if (data->u.vector && data->u.vector < 0x10)
258 r = -EINVAL;
259 else {
260 kvm->arch.xen.upcall_vector = data->u.vector;
261 r = 0;
262 }
263 break;
264
265 default:
266 break;
267 }
268
269 mutex_unlock(&kvm->lock);
270 return r;
271}
272
273int kvm_xen_hvm_get_attr(struct kvm *kvm, struct kvm_xen_hvm_attr *data)
274{
275 int r = -ENOENT;
276
277 mutex_lock(&kvm->lock);
278
279 switch (data->type) {
280 case KVM_XEN_ATTR_TYPE_LONG_MODE:
281 data->u.long_mode = kvm->arch.xen.long_mode;
282 r = 0;
283 break;
284
285 case KVM_XEN_ATTR_TYPE_SHARED_INFO:
286 if (kvm->arch.xen.shinfo_set)
287 data->u.shared_info.gfn = gpa_to_gfn(kvm->arch.xen.shinfo_cache.gpa);
288 else
289 data->u.shared_info.gfn = GPA_INVALID;
290 r = 0;
291 break;
292
293 case KVM_XEN_ATTR_TYPE_UPCALL_VECTOR:
294 data->u.vector = kvm->arch.xen.upcall_vector;
295 r = 0;
296 break;
297
298 default:
299 break;
300 }
301
302 mutex_unlock(&kvm->lock);
303 return r;
304}
305
306int kvm_xen_vcpu_set_attr(struct kvm_vcpu *vcpu, struct kvm_xen_vcpu_attr *data)
307{
308 int idx, r = -ENOENT;
309
310 mutex_lock(&vcpu->kvm->lock);
311 idx = srcu_read_lock(&vcpu->kvm->srcu);
312
313 switch (data->type) {
314 case KVM_XEN_VCPU_ATTR_TYPE_VCPU_INFO:
315 /* No compat necessary here. */
316 BUILD_BUG_ON(sizeof(struct vcpu_info) !=
317 sizeof(struct compat_vcpu_info));
318 BUILD_BUG_ON(offsetof(struct vcpu_info, time) !=
319 offsetof(struct compat_vcpu_info, time));
320
321 if (data->u.gpa == GPA_INVALID) {
322 vcpu->arch.xen.vcpu_info_set = false;
323 r = 0;
324 break;
325 }
326
327 r = kvm_gfn_to_hva_cache_init(vcpu->kvm,
328 &vcpu->arch.xen.vcpu_info_cache,
329 data->u.gpa,
330 sizeof(struct vcpu_info));
331 if (!r) {
332 vcpu->arch.xen.vcpu_info_set = true;
333 kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu);
334 }
335 break;
336
337 case KVM_XEN_VCPU_ATTR_TYPE_VCPU_TIME_INFO:
338 if (data->u.gpa == GPA_INVALID) {
339 vcpu->arch.xen.vcpu_time_info_set = false;
340 r = 0;
341 break;
342 }
343
344 r = kvm_gfn_to_hva_cache_init(vcpu->kvm,
345 &vcpu->arch.xen.vcpu_time_info_cache,
346 data->u.gpa,
347 sizeof(struct pvclock_vcpu_time_info));
348 if (!r) {
349 vcpu->arch.xen.vcpu_time_info_set = true;
350 kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu);
351 }
352 break;
353
354 case KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_ADDR:
355 if (!sched_info_on()) {
356 r = -EOPNOTSUPP;
357 break;
358 }
359 if (data->u.gpa == GPA_INVALID) {
360 vcpu->arch.xen.runstate_set = false;
361 r = 0;
362 break;
363 }
364
365 r = kvm_gfn_to_hva_cache_init(vcpu->kvm,
366 &vcpu->arch.xen.runstate_cache,
367 data->u.gpa,
368 sizeof(struct vcpu_runstate_info));
369 if (!r) {
370 vcpu->arch.xen.runstate_set = true;
371 }
372 break;
373
374 case KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_CURRENT:
375 if (!sched_info_on()) {
376 r = -EOPNOTSUPP;
377 break;
378 }
379 if (data->u.runstate.state > RUNSTATE_offline) {
380 r = -EINVAL;
381 break;
382 }
383
384 kvm_xen_update_runstate(vcpu, data->u.runstate.state);
385 r = 0;
386 break;
387
388 case KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_DATA:
389 if (!sched_info_on()) {
390 r = -EOPNOTSUPP;
391 break;
392 }
393 if (data->u.runstate.state > RUNSTATE_offline) {
394 r = -EINVAL;
395 break;
396 }
397 if (data->u.runstate.state_entry_time !=
398 (data->u.runstate.time_running +
399 data->u.runstate.time_runnable +
400 data->u.runstate.time_blocked +
401 data->u.runstate.time_offline)) {
402 r = -EINVAL;
403 break;
404 }
405 if (get_kvmclock_ns(vcpu->kvm) <
406 data->u.runstate.state_entry_time) {
407 r = -EINVAL;
408 break;
409 }
410
411 vcpu->arch.xen.current_runstate = data->u.runstate.state;
412 vcpu->arch.xen.runstate_entry_time =
413 data->u.runstate.state_entry_time;
414 vcpu->arch.xen.runstate_times[RUNSTATE_running] =
415 data->u.runstate.time_running;
416 vcpu->arch.xen.runstate_times[RUNSTATE_runnable] =
417 data->u.runstate.time_runnable;
418 vcpu->arch.xen.runstate_times[RUNSTATE_blocked] =
419 data->u.runstate.time_blocked;
420 vcpu->arch.xen.runstate_times[RUNSTATE_offline] =
421 data->u.runstate.time_offline;
422 vcpu->arch.xen.last_steal = current->sched_info.run_delay;
423 r = 0;
424 break;
425
426 case KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_ADJUST:
427 if (!sched_info_on()) {
428 r = -EOPNOTSUPP;
429 break;
430 }
431 if (data->u.runstate.state > RUNSTATE_offline &&
432 data->u.runstate.state != (u64)-1) {
433 r = -EINVAL;
434 break;
435 }
436 /* The adjustment must add up */
437 if (data->u.runstate.state_entry_time !=
438 (data->u.runstate.time_running +
439 data->u.runstate.time_runnable +
440 data->u.runstate.time_blocked +
441 data->u.runstate.time_offline)) {
442 r = -EINVAL;
443 break;
444 }
445
446 if (get_kvmclock_ns(vcpu->kvm) <
447 (vcpu->arch.xen.runstate_entry_time +
448 data->u.runstate.state_entry_time)) {
449 r = -EINVAL;
450 break;
451 }
452
453 vcpu->arch.xen.runstate_entry_time +=
454 data->u.runstate.state_entry_time;
455 vcpu->arch.xen.runstate_times[RUNSTATE_running] +=
456 data->u.runstate.time_running;
457 vcpu->arch.xen.runstate_times[RUNSTATE_runnable] +=
458 data->u.runstate.time_runnable;
459 vcpu->arch.xen.runstate_times[RUNSTATE_blocked] +=
460 data->u.runstate.time_blocked;
461 vcpu->arch.xen.runstate_times[RUNSTATE_offline] +=
462 data->u.runstate.time_offline;
463
464 if (data->u.runstate.state <= RUNSTATE_offline)
465 kvm_xen_update_runstate(vcpu, data->u.runstate.state);
466 r = 0;
467 break;
468
469 default:
470 break;
471 }
472
473 srcu_read_unlock(&vcpu->kvm->srcu, idx);
474 mutex_unlock(&vcpu->kvm->lock);
475 return r;
476}
477
478int kvm_xen_vcpu_get_attr(struct kvm_vcpu *vcpu, struct kvm_xen_vcpu_attr *data)
479{
480 int r = -ENOENT;
481
482 mutex_lock(&vcpu->kvm->lock);
483
484 switch (data->type) {
485 case KVM_XEN_VCPU_ATTR_TYPE_VCPU_INFO:
486 if (vcpu->arch.xen.vcpu_info_set)
487 data->u.gpa = vcpu->arch.xen.vcpu_info_cache.gpa;
488 else
489 data->u.gpa = GPA_INVALID;
490 r = 0;
491 break;
492
493 case KVM_XEN_VCPU_ATTR_TYPE_VCPU_TIME_INFO:
494 if (vcpu->arch.xen.vcpu_time_info_set)
495 data->u.gpa = vcpu->arch.xen.vcpu_time_info_cache.gpa;
496 else
497 data->u.gpa = GPA_INVALID;
498 r = 0;
499 break;
500
501 case KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_ADDR:
502 if (!sched_info_on()) {
503 r = -EOPNOTSUPP;
504 break;
505 }
506 if (vcpu->arch.xen.runstate_set) {
507 data->u.gpa = vcpu->arch.xen.runstate_cache.gpa;
508 r = 0;
509 }
510 break;
511
512 case KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_CURRENT:
513 if (!sched_info_on()) {
514 r = -EOPNOTSUPP;
515 break;
516 }
517 data->u.runstate.state = vcpu->arch.xen.current_runstate;
518 r = 0;
519 break;
520
521 case KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_DATA:
522 if (!sched_info_on()) {
523 r = -EOPNOTSUPP;
524 break;
525 }
526 data->u.runstate.state = vcpu->arch.xen.current_runstate;
527 data->u.runstate.state_entry_time =
528 vcpu->arch.xen.runstate_entry_time;
529 data->u.runstate.time_running =
530 vcpu->arch.xen.runstate_times[RUNSTATE_running];
531 data->u.runstate.time_runnable =
532 vcpu->arch.xen.runstate_times[RUNSTATE_runnable];
533 data->u.runstate.time_blocked =
534 vcpu->arch.xen.runstate_times[RUNSTATE_blocked];
535 data->u.runstate.time_offline =
536 vcpu->arch.xen.runstate_times[RUNSTATE_offline];
537 r = 0;
538 break;
539
540 case KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_ADJUST:
541 r = -EINVAL;
542 break;
543
544 default:
545 break;
546 }
547
548 mutex_unlock(&vcpu->kvm->lock);
549 return r;
550}
551
552int kvm_xen_write_hypercall_page(struct kvm_vcpu *vcpu, u64 data)
553{
554 struct kvm *kvm = vcpu->kvm;
555 u32 page_num = data & ~PAGE_MASK;
556 u64 page_addr = data & PAGE_MASK;
557 bool lm = is_long_mode(vcpu);
558
559 /* Latch long_mode for shared_info pages etc. */
560 vcpu->kvm->arch.xen.long_mode = lm;
561
562 /*
563 * If Xen hypercall intercept is enabled, fill the hypercall
564 * page with VMCALL/VMMCALL instructions since that's what
565 * we catch. Else the VMM has provided the hypercall pages
566 * with instructions of its own choosing, so use those.
567 */
568 if (kvm_xen_hypercall_enabled(kvm)) {
569 u8 instructions[32];
570 int i;
571
572 if (page_num)
573 return 1;
574
575 /* mov imm32, %eax */
576 instructions[0] = 0xb8;
577
578 /* vmcall / vmmcall */
579 kvm_x86_ops.patch_hypercall(vcpu, instructions + 5);
580
581 /* ret */
582 instructions[8] = 0xc3;
583
584 /* int3 to pad */
585 memset(instructions + 9, 0xcc, sizeof(instructions) - 9);
586
587 for (i = 0; i < PAGE_SIZE / sizeof(instructions); i++) {
588 *(u32 *)&instructions[1] = i;
589 if (kvm_vcpu_write_guest(vcpu,
590 page_addr + (i * sizeof(instructions)),
591 instructions, sizeof(instructions)))
592 return 1;
593 }
594 } else {
595 /*
596 * Note, truncation is a non-issue as 'lm' is guaranteed to be
597 * false for a 32-bit kernel, i.e. when hva_t is only 4 bytes.
598 */
599 hva_t blob_addr = lm ? kvm->arch.xen_hvm_config.blob_addr_64
600 : kvm->arch.xen_hvm_config.blob_addr_32;
601 u8 blob_size = lm ? kvm->arch.xen_hvm_config.blob_size_64
602 : kvm->arch.xen_hvm_config.blob_size_32;
603 u8 *page;
604
605 if (page_num >= blob_size)
606 return 1;
607
608 blob_addr += page_num * PAGE_SIZE;
609
610 page = memdup_user((u8 __user *)blob_addr, PAGE_SIZE);
611 if (IS_ERR(page))
612 return PTR_ERR(page);
613
614 if (kvm_vcpu_write_guest(vcpu, page_addr, page, PAGE_SIZE)) {
615 kfree(page);
616 return 1;
617 }
618 }
619 return 0;
620}
621
622int kvm_xen_hvm_config(struct kvm *kvm, struct kvm_xen_hvm_config *xhc)
623{
624 if (xhc->flags & ~KVM_XEN_HVM_CONFIG_INTERCEPT_HCALL)
625 return -EINVAL;
626
627 /*
628 * With hypercall interception the kernel generates its own
629 * hypercall page so it must not be provided.
630 */
631 if ((xhc->flags & KVM_XEN_HVM_CONFIG_INTERCEPT_HCALL) &&
632 (xhc->blob_addr_32 || xhc->blob_addr_64 ||
633 xhc->blob_size_32 || xhc->blob_size_64))
634 return -EINVAL;
635
636 mutex_lock(&kvm->lock);
637
638 if (xhc->msr && !kvm->arch.xen_hvm_config.msr)
639 static_branch_inc(&kvm_xen_enabled.key);
640 else if (!xhc->msr && kvm->arch.xen_hvm_config.msr)
641 static_branch_slow_dec_deferred(&kvm_xen_enabled);
642
643 memcpy(&kvm->arch.xen_hvm_config, xhc, sizeof(*xhc));
644
645 mutex_unlock(&kvm->lock);
646 return 0;
647}
648
649void kvm_xen_destroy_vm(struct kvm *kvm)
650{
651 if (kvm->arch.xen_hvm_config.msr)
652 static_branch_slow_dec_deferred(&kvm_xen_enabled);
653}
654
655static int kvm_xen_hypercall_set_result(struct kvm_vcpu *vcpu, u64 result)
656{
657 kvm_rax_write(vcpu, result);
658 return kvm_skip_emulated_instruction(vcpu);
659}
660
661static int kvm_xen_hypercall_complete_userspace(struct kvm_vcpu *vcpu)
662{
663 struct kvm_run *run = vcpu->run;
664
665 if (unlikely(!kvm_is_linear_rip(vcpu, vcpu->arch.xen.hypercall_rip)))
666 return 1;
667
668 return kvm_xen_hypercall_set_result(vcpu, run->xen.u.hcall.result);
669}
670
671int kvm_xen_hypercall(struct kvm_vcpu *vcpu)
672{
673 bool longmode;
674 u64 input, params[6];
675
676 input = (u64)kvm_register_read(vcpu, VCPU_REGS_RAX);
677
678 /* Hyper-V hypercalls get bit 31 set in EAX */
679 if ((input & 0x80000000) &&
680 kvm_hv_hypercall_enabled(vcpu))
681 return kvm_hv_hypercall(vcpu);
682
683 longmode = is_64_bit_mode(vcpu);
684 if (!longmode) {
685 params[0] = (u32)kvm_rbx_read(vcpu);
686 params[1] = (u32)kvm_rcx_read(vcpu);
687 params[2] = (u32)kvm_rdx_read(vcpu);
688 params[3] = (u32)kvm_rsi_read(vcpu);
689 params[4] = (u32)kvm_rdi_read(vcpu);
690 params[5] = (u32)kvm_rbp_read(vcpu);
691 }
692#ifdef CONFIG_X86_64
693 else {
694 params[0] = (u64)kvm_rdi_read(vcpu);
695 params[1] = (u64)kvm_rsi_read(vcpu);
696 params[2] = (u64)kvm_rdx_read(vcpu);
697 params[3] = (u64)kvm_r10_read(vcpu);
698 params[4] = (u64)kvm_r8_read(vcpu);
699 params[5] = (u64)kvm_r9_read(vcpu);
700 }
701#endif
702 trace_kvm_xen_hypercall(input, params[0], params[1], params[2],
703 params[3], params[4], params[5]);
704
705 vcpu->run->exit_reason = KVM_EXIT_XEN;
706 vcpu->run->xen.type = KVM_EXIT_XEN_HCALL;
707 vcpu->run->xen.u.hcall.longmode = longmode;
708 vcpu->run->xen.u.hcall.cpl = kvm_x86_ops.get_cpl(vcpu);
709 vcpu->run->xen.u.hcall.input = input;
710 vcpu->run->xen.u.hcall.params[0] = params[0];
711 vcpu->run->xen.u.hcall.params[1] = params[1];
712 vcpu->run->xen.u.hcall.params[2] = params[2];
713 vcpu->run->xen.u.hcall.params[3] = params[3];
714 vcpu->run->xen.u.hcall.params[4] = params[4];
715 vcpu->run->xen.u.hcall.params[5] = params[5];
716 vcpu->arch.xen.hypercall_rip = kvm_get_linear_rip(vcpu);
717 vcpu->arch.complete_userspace_io =
718 kvm_xen_hypercall_complete_userspace;
719
720 return 0;
721}