]> git.ipfire.org Git - thirdparty/linux.git/blob - arch/x86/kvm/hyperv.c
io_uring: reset -EBUSY error when io sq thread is waken up
[thirdparty/linux.git] / arch / x86 / kvm / hyperv.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * KVM Microsoft Hyper-V emulation
4 *
5 * derived from arch/x86/kvm/x86.c
6 *
7 * Copyright (C) 2006 Qumranet, Inc.
8 * Copyright (C) 2008 Qumranet, Inc.
9 * Copyright IBM Corporation, 2008
10 * Copyright 2010 Red Hat, Inc. and/or its affiliates.
11 * Copyright (C) 2015 Andrey Smetanin <asmetanin@virtuozzo.com>
12 *
13 * Authors:
14 * Avi Kivity <avi@qumranet.com>
15 * Yaniv Kamay <yaniv@qumranet.com>
16 * Amit Shah <amit.shah@qumranet.com>
17 * Ben-Ami Yassour <benami@il.ibm.com>
18 * Andrey Smetanin <asmetanin@virtuozzo.com>
19 */
20
21 #include "x86.h"
22 #include "lapic.h"
23 #include "ioapic.h"
24 #include "hyperv.h"
25
26 #include <linux/cpu.h>
27 #include <linux/kvm_host.h>
28 #include <linux/highmem.h>
29 #include <linux/sched/cputime.h>
30 #include <linux/eventfd.h>
31
32 #include <asm/apicdef.h>
33 #include <trace/events/kvm.h>
34
35 #include "trace.h"
36 #include "irq.h"
37
38 #define KVM_HV_MAX_SPARSE_VCPU_SET_BITS DIV_ROUND_UP(KVM_MAX_VCPUS, 64)
39
40 static void stimer_mark_pending(struct kvm_vcpu_hv_stimer *stimer,
41 bool vcpu_kick);
42
43 static inline u64 synic_read_sint(struct kvm_vcpu_hv_synic *synic, int sint)
44 {
45 return atomic64_read(&synic->sint[sint]);
46 }
47
48 static inline int synic_get_sint_vector(u64 sint_value)
49 {
50 if (sint_value & HV_SYNIC_SINT_MASKED)
51 return -1;
52 return sint_value & HV_SYNIC_SINT_VECTOR_MASK;
53 }
54
55 static bool synic_has_vector_connected(struct kvm_vcpu_hv_synic *synic,
56 int vector)
57 {
58 int i;
59
60 for (i = 0; i < ARRAY_SIZE(synic->sint); i++) {
61 if (synic_get_sint_vector(synic_read_sint(synic, i)) == vector)
62 return true;
63 }
64 return false;
65 }
66
67 static bool synic_has_vector_auto_eoi(struct kvm_vcpu_hv_synic *synic,
68 int vector)
69 {
70 int i;
71 u64 sint_value;
72
73 for (i = 0; i < ARRAY_SIZE(synic->sint); i++) {
74 sint_value = synic_read_sint(synic, i);
75 if (synic_get_sint_vector(sint_value) == vector &&
76 sint_value & HV_SYNIC_SINT_AUTO_EOI)
77 return true;
78 }
79 return false;
80 }
81
82 static void synic_update_vector(struct kvm_vcpu_hv_synic *synic,
83 int vector)
84 {
85 if (vector < HV_SYNIC_FIRST_VALID_VECTOR)
86 return;
87
88 if (synic_has_vector_connected(synic, vector))
89 __set_bit(vector, synic->vec_bitmap);
90 else
91 __clear_bit(vector, synic->vec_bitmap);
92
93 if (synic_has_vector_auto_eoi(synic, vector))
94 __set_bit(vector, synic->auto_eoi_bitmap);
95 else
96 __clear_bit(vector, synic->auto_eoi_bitmap);
97 }
98
99 static int synic_set_sint(struct kvm_vcpu_hv_synic *synic, int sint,
100 u64 data, bool host)
101 {
102 int vector, old_vector;
103 bool masked;
104
105 vector = data & HV_SYNIC_SINT_VECTOR_MASK;
106 masked = data & HV_SYNIC_SINT_MASKED;
107
108 /*
109 * Valid vectors are 16-255, however, nested Hyper-V attempts to write
110 * default '0x10000' value on boot and this should not #GP. We need to
111 * allow zero-initing the register from host as well.
112 */
113 if (vector < HV_SYNIC_FIRST_VALID_VECTOR && !host && !masked)
114 return 1;
115 /*
116 * Guest may configure multiple SINTs to use the same vector, so
117 * we maintain a bitmap of vectors handled by synic, and a
118 * bitmap of vectors with auto-eoi behavior. The bitmaps are
119 * updated here, and atomically queried on fast paths.
120 */
121 old_vector = synic_read_sint(synic, sint) & HV_SYNIC_SINT_VECTOR_MASK;
122
123 atomic64_set(&synic->sint[sint], data);
124
125 synic_update_vector(synic, old_vector);
126
127 synic_update_vector(synic, vector);
128
129 /* Load SynIC vectors into EOI exit bitmap */
130 kvm_make_request(KVM_REQ_SCAN_IOAPIC, synic_to_vcpu(synic));
131 return 0;
132 }
133
134 static struct kvm_vcpu *get_vcpu_by_vpidx(struct kvm *kvm, u32 vpidx)
135 {
136 struct kvm_vcpu *vcpu = NULL;
137 int i;
138
139 if (vpidx >= KVM_MAX_VCPUS)
140 return NULL;
141
142 vcpu = kvm_get_vcpu(kvm, vpidx);
143 if (vcpu && vcpu_to_hv_vcpu(vcpu)->vp_index == vpidx)
144 return vcpu;
145 kvm_for_each_vcpu(i, vcpu, kvm)
146 if (vcpu_to_hv_vcpu(vcpu)->vp_index == vpidx)
147 return vcpu;
148 return NULL;
149 }
150
151 static struct kvm_vcpu_hv_synic *synic_get(struct kvm *kvm, u32 vpidx)
152 {
153 struct kvm_vcpu *vcpu;
154 struct kvm_vcpu_hv_synic *synic;
155
156 vcpu = get_vcpu_by_vpidx(kvm, vpidx);
157 if (!vcpu)
158 return NULL;
159 synic = vcpu_to_synic(vcpu);
160 return (synic->active) ? synic : NULL;
161 }
162
163 static void kvm_hv_notify_acked_sint(struct kvm_vcpu *vcpu, u32 sint)
164 {
165 struct kvm *kvm = vcpu->kvm;
166 struct kvm_vcpu_hv_synic *synic = vcpu_to_synic(vcpu);
167 struct kvm_vcpu_hv *hv_vcpu = vcpu_to_hv_vcpu(vcpu);
168 struct kvm_vcpu_hv_stimer *stimer;
169 int gsi, idx;
170
171 trace_kvm_hv_notify_acked_sint(vcpu->vcpu_id, sint);
172
173 /* Try to deliver pending Hyper-V SynIC timers messages */
174 for (idx = 0; idx < ARRAY_SIZE(hv_vcpu->stimer); idx++) {
175 stimer = &hv_vcpu->stimer[idx];
176 if (stimer->msg_pending && stimer->config.enable &&
177 !stimer->config.direct_mode &&
178 stimer->config.sintx == sint)
179 stimer_mark_pending(stimer, false);
180 }
181
182 idx = srcu_read_lock(&kvm->irq_srcu);
183 gsi = atomic_read(&synic->sint_to_gsi[sint]);
184 if (gsi != -1)
185 kvm_notify_acked_gsi(kvm, gsi);
186 srcu_read_unlock(&kvm->irq_srcu, idx);
187 }
188
189 static void synic_exit(struct kvm_vcpu_hv_synic *synic, u32 msr)
190 {
191 struct kvm_vcpu *vcpu = synic_to_vcpu(synic);
192 struct kvm_vcpu_hv *hv_vcpu = &vcpu->arch.hyperv;
193
194 hv_vcpu->exit.type = KVM_EXIT_HYPERV_SYNIC;
195 hv_vcpu->exit.u.synic.msr = msr;
196 hv_vcpu->exit.u.synic.control = synic->control;
197 hv_vcpu->exit.u.synic.evt_page = synic->evt_page;
198 hv_vcpu->exit.u.synic.msg_page = synic->msg_page;
199
200 kvm_make_request(KVM_REQ_HV_EXIT, vcpu);
201 }
202
203 static int synic_set_msr(struct kvm_vcpu_hv_synic *synic,
204 u32 msr, u64 data, bool host)
205 {
206 struct kvm_vcpu *vcpu = synic_to_vcpu(synic);
207 int ret;
208
209 if (!synic->active && !host)
210 return 1;
211
212 trace_kvm_hv_synic_set_msr(vcpu->vcpu_id, msr, data, host);
213
214 ret = 0;
215 switch (msr) {
216 case HV_X64_MSR_SCONTROL:
217 synic->control = data;
218 if (!host)
219 synic_exit(synic, msr);
220 break;
221 case HV_X64_MSR_SVERSION:
222 if (!host) {
223 ret = 1;
224 break;
225 }
226 synic->version = data;
227 break;
228 case HV_X64_MSR_SIEFP:
229 if ((data & HV_SYNIC_SIEFP_ENABLE) && !host &&
230 !synic->dont_zero_synic_pages)
231 if (kvm_clear_guest(vcpu->kvm,
232 data & PAGE_MASK, PAGE_SIZE)) {
233 ret = 1;
234 break;
235 }
236 synic->evt_page = data;
237 if (!host)
238 synic_exit(synic, msr);
239 break;
240 case HV_X64_MSR_SIMP:
241 if ((data & HV_SYNIC_SIMP_ENABLE) && !host &&
242 !synic->dont_zero_synic_pages)
243 if (kvm_clear_guest(vcpu->kvm,
244 data & PAGE_MASK, PAGE_SIZE)) {
245 ret = 1;
246 break;
247 }
248 synic->msg_page = data;
249 if (!host)
250 synic_exit(synic, msr);
251 break;
252 case HV_X64_MSR_EOM: {
253 int i;
254
255 for (i = 0; i < ARRAY_SIZE(synic->sint); i++)
256 kvm_hv_notify_acked_sint(vcpu, i);
257 break;
258 }
259 case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
260 ret = synic_set_sint(synic, msr - HV_X64_MSR_SINT0, data, host);
261 break;
262 default:
263 ret = 1;
264 break;
265 }
266 return ret;
267 }
268
269 static int synic_get_msr(struct kvm_vcpu_hv_synic *synic, u32 msr, u64 *pdata,
270 bool host)
271 {
272 int ret;
273
274 if (!synic->active && !host)
275 return 1;
276
277 ret = 0;
278 switch (msr) {
279 case HV_X64_MSR_SCONTROL:
280 *pdata = synic->control;
281 break;
282 case HV_X64_MSR_SVERSION:
283 *pdata = synic->version;
284 break;
285 case HV_X64_MSR_SIEFP:
286 *pdata = synic->evt_page;
287 break;
288 case HV_X64_MSR_SIMP:
289 *pdata = synic->msg_page;
290 break;
291 case HV_X64_MSR_EOM:
292 *pdata = 0;
293 break;
294 case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
295 *pdata = atomic64_read(&synic->sint[msr - HV_X64_MSR_SINT0]);
296 break;
297 default:
298 ret = 1;
299 break;
300 }
301 return ret;
302 }
303
304 static int synic_set_irq(struct kvm_vcpu_hv_synic *synic, u32 sint)
305 {
306 struct kvm_vcpu *vcpu = synic_to_vcpu(synic);
307 struct kvm_lapic_irq irq;
308 int ret, vector;
309
310 if (sint >= ARRAY_SIZE(synic->sint))
311 return -EINVAL;
312
313 vector = synic_get_sint_vector(synic_read_sint(synic, sint));
314 if (vector < 0)
315 return -ENOENT;
316
317 memset(&irq, 0, sizeof(irq));
318 irq.shorthand = APIC_DEST_SELF;
319 irq.dest_mode = APIC_DEST_PHYSICAL;
320 irq.delivery_mode = APIC_DM_FIXED;
321 irq.vector = vector;
322 irq.level = 1;
323
324 ret = kvm_irq_delivery_to_apic(vcpu->kvm, vcpu->arch.apic, &irq, NULL);
325 trace_kvm_hv_synic_set_irq(vcpu->vcpu_id, sint, irq.vector, ret);
326 return ret;
327 }
328
329 int kvm_hv_synic_set_irq(struct kvm *kvm, u32 vpidx, u32 sint)
330 {
331 struct kvm_vcpu_hv_synic *synic;
332
333 synic = synic_get(kvm, vpidx);
334 if (!synic)
335 return -EINVAL;
336
337 return synic_set_irq(synic, sint);
338 }
339
340 void kvm_hv_synic_send_eoi(struct kvm_vcpu *vcpu, int vector)
341 {
342 struct kvm_vcpu_hv_synic *synic = vcpu_to_synic(vcpu);
343 int i;
344
345 trace_kvm_hv_synic_send_eoi(vcpu->vcpu_id, vector);
346
347 for (i = 0; i < ARRAY_SIZE(synic->sint); i++)
348 if (synic_get_sint_vector(synic_read_sint(synic, i)) == vector)
349 kvm_hv_notify_acked_sint(vcpu, i);
350 }
351
352 static int kvm_hv_set_sint_gsi(struct kvm *kvm, u32 vpidx, u32 sint, int gsi)
353 {
354 struct kvm_vcpu_hv_synic *synic;
355
356 synic = synic_get(kvm, vpidx);
357 if (!synic)
358 return -EINVAL;
359
360 if (sint >= ARRAY_SIZE(synic->sint_to_gsi))
361 return -EINVAL;
362
363 atomic_set(&synic->sint_to_gsi[sint], gsi);
364 return 0;
365 }
366
367 void kvm_hv_irq_routing_update(struct kvm *kvm)
368 {
369 struct kvm_irq_routing_table *irq_rt;
370 struct kvm_kernel_irq_routing_entry *e;
371 u32 gsi;
372
373 irq_rt = srcu_dereference_check(kvm->irq_routing, &kvm->irq_srcu,
374 lockdep_is_held(&kvm->irq_lock));
375
376 for (gsi = 0; gsi < irq_rt->nr_rt_entries; gsi++) {
377 hlist_for_each_entry(e, &irq_rt->map[gsi], link) {
378 if (e->type == KVM_IRQ_ROUTING_HV_SINT)
379 kvm_hv_set_sint_gsi(kvm, e->hv_sint.vcpu,
380 e->hv_sint.sint, gsi);
381 }
382 }
383 }
384
385 static void synic_init(struct kvm_vcpu_hv_synic *synic)
386 {
387 int i;
388
389 memset(synic, 0, sizeof(*synic));
390 synic->version = HV_SYNIC_VERSION_1;
391 for (i = 0; i < ARRAY_SIZE(synic->sint); i++) {
392 atomic64_set(&synic->sint[i], HV_SYNIC_SINT_MASKED);
393 atomic_set(&synic->sint_to_gsi[i], -1);
394 }
395 }
396
397 static u64 get_time_ref_counter(struct kvm *kvm)
398 {
399 struct kvm_hv *hv = &kvm->arch.hyperv;
400 struct kvm_vcpu *vcpu;
401 u64 tsc;
402
403 /*
404 * The guest has not set up the TSC page or the clock isn't
405 * stable, fall back to get_kvmclock_ns.
406 */
407 if (!hv->tsc_ref.tsc_sequence)
408 return div_u64(get_kvmclock_ns(kvm), 100);
409
410 vcpu = kvm_get_vcpu(kvm, 0);
411 tsc = kvm_read_l1_tsc(vcpu, rdtsc());
412 return mul_u64_u64_shr(tsc, hv->tsc_ref.tsc_scale, 64)
413 + hv->tsc_ref.tsc_offset;
414 }
415
416 static void stimer_mark_pending(struct kvm_vcpu_hv_stimer *stimer,
417 bool vcpu_kick)
418 {
419 struct kvm_vcpu *vcpu = stimer_to_vcpu(stimer);
420
421 set_bit(stimer->index,
422 vcpu_to_hv_vcpu(vcpu)->stimer_pending_bitmap);
423 kvm_make_request(KVM_REQ_HV_STIMER, vcpu);
424 if (vcpu_kick)
425 kvm_vcpu_kick(vcpu);
426 }
427
428 static void stimer_cleanup(struct kvm_vcpu_hv_stimer *stimer)
429 {
430 struct kvm_vcpu *vcpu = stimer_to_vcpu(stimer);
431
432 trace_kvm_hv_stimer_cleanup(stimer_to_vcpu(stimer)->vcpu_id,
433 stimer->index);
434
435 hrtimer_cancel(&stimer->timer);
436 clear_bit(stimer->index,
437 vcpu_to_hv_vcpu(vcpu)->stimer_pending_bitmap);
438 stimer->msg_pending = false;
439 stimer->exp_time = 0;
440 }
441
442 static enum hrtimer_restart stimer_timer_callback(struct hrtimer *timer)
443 {
444 struct kvm_vcpu_hv_stimer *stimer;
445
446 stimer = container_of(timer, struct kvm_vcpu_hv_stimer, timer);
447 trace_kvm_hv_stimer_callback(stimer_to_vcpu(stimer)->vcpu_id,
448 stimer->index);
449 stimer_mark_pending(stimer, true);
450
451 return HRTIMER_NORESTART;
452 }
453
454 /*
455 * stimer_start() assumptions:
456 * a) stimer->count is not equal to 0
457 * b) stimer->config has HV_STIMER_ENABLE flag
458 */
459 static int stimer_start(struct kvm_vcpu_hv_stimer *stimer)
460 {
461 u64 time_now;
462 ktime_t ktime_now;
463
464 time_now = get_time_ref_counter(stimer_to_vcpu(stimer)->kvm);
465 ktime_now = ktime_get();
466
467 if (stimer->config.periodic) {
468 if (stimer->exp_time) {
469 if (time_now >= stimer->exp_time) {
470 u64 remainder;
471
472 div64_u64_rem(time_now - stimer->exp_time,
473 stimer->count, &remainder);
474 stimer->exp_time =
475 time_now + (stimer->count - remainder);
476 }
477 } else
478 stimer->exp_time = time_now + stimer->count;
479
480 trace_kvm_hv_stimer_start_periodic(
481 stimer_to_vcpu(stimer)->vcpu_id,
482 stimer->index,
483 time_now, stimer->exp_time);
484
485 hrtimer_start(&stimer->timer,
486 ktime_add_ns(ktime_now,
487 100 * (stimer->exp_time - time_now)),
488 HRTIMER_MODE_ABS);
489 return 0;
490 }
491 stimer->exp_time = stimer->count;
492 if (time_now >= stimer->count) {
493 /*
494 * Expire timer according to Hypervisor Top-Level Functional
495 * specification v4(15.3.1):
496 * "If a one shot is enabled and the specified count is in
497 * the past, it will expire immediately."
498 */
499 stimer_mark_pending(stimer, false);
500 return 0;
501 }
502
503 trace_kvm_hv_stimer_start_one_shot(stimer_to_vcpu(stimer)->vcpu_id,
504 stimer->index,
505 time_now, stimer->count);
506
507 hrtimer_start(&stimer->timer,
508 ktime_add_ns(ktime_now, 100 * (stimer->count - time_now)),
509 HRTIMER_MODE_ABS);
510 return 0;
511 }
512
513 static int stimer_set_config(struct kvm_vcpu_hv_stimer *stimer, u64 config,
514 bool host)
515 {
516 union hv_stimer_config new_config = {.as_uint64 = config},
517 old_config = {.as_uint64 = stimer->config.as_uint64};
518
519 trace_kvm_hv_stimer_set_config(stimer_to_vcpu(stimer)->vcpu_id,
520 stimer->index, config, host);
521
522 stimer_cleanup(stimer);
523 if (old_config.enable &&
524 !new_config.direct_mode && new_config.sintx == 0)
525 new_config.enable = 0;
526 stimer->config.as_uint64 = new_config.as_uint64;
527
528 if (stimer->config.enable)
529 stimer_mark_pending(stimer, false);
530
531 return 0;
532 }
533
534 static int stimer_set_count(struct kvm_vcpu_hv_stimer *stimer, u64 count,
535 bool host)
536 {
537 trace_kvm_hv_stimer_set_count(stimer_to_vcpu(stimer)->vcpu_id,
538 stimer->index, count, host);
539
540 stimer_cleanup(stimer);
541 stimer->count = count;
542 if (stimer->count == 0)
543 stimer->config.enable = 0;
544 else if (stimer->config.auto_enable)
545 stimer->config.enable = 1;
546
547 if (stimer->config.enable)
548 stimer_mark_pending(stimer, false);
549
550 return 0;
551 }
552
553 static int stimer_get_config(struct kvm_vcpu_hv_stimer *stimer, u64 *pconfig)
554 {
555 *pconfig = stimer->config.as_uint64;
556 return 0;
557 }
558
559 static int stimer_get_count(struct kvm_vcpu_hv_stimer *stimer, u64 *pcount)
560 {
561 *pcount = stimer->count;
562 return 0;
563 }
564
565 static int synic_deliver_msg(struct kvm_vcpu_hv_synic *synic, u32 sint,
566 struct hv_message *src_msg, bool no_retry)
567 {
568 struct kvm_vcpu *vcpu = synic_to_vcpu(synic);
569 int msg_off = offsetof(struct hv_message_page, sint_message[sint]);
570 gfn_t msg_page_gfn;
571 struct hv_message_header hv_hdr;
572 int r;
573
574 if (!(synic->msg_page & HV_SYNIC_SIMP_ENABLE))
575 return -ENOENT;
576
577 msg_page_gfn = synic->msg_page >> PAGE_SHIFT;
578
579 /*
580 * Strictly following the spec-mandated ordering would assume setting
581 * .msg_pending before checking .message_type. However, this function
582 * is only called in vcpu context so the entire update is atomic from
583 * guest POV and thus the exact order here doesn't matter.
584 */
585 r = kvm_vcpu_read_guest_page(vcpu, msg_page_gfn, &hv_hdr.message_type,
586 msg_off + offsetof(struct hv_message,
587 header.message_type),
588 sizeof(hv_hdr.message_type));
589 if (r < 0)
590 return r;
591
592 if (hv_hdr.message_type != HVMSG_NONE) {
593 if (no_retry)
594 return 0;
595
596 hv_hdr.message_flags.msg_pending = 1;
597 r = kvm_vcpu_write_guest_page(vcpu, msg_page_gfn,
598 &hv_hdr.message_flags,
599 msg_off +
600 offsetof(struct hv_message,
601 header.message_flags),
602 sizeof(hv_hdr.message_flags));
603 if (r < 0)
604 return r;
605 return -EAGAIN;
606 }
607
608 r = kvm_vcpu_write_guest_page(vcpu, msg_page_gfn, src_msg, msg_off,
609 sizeof(src_msg->header) +
610 src_msg->header.payload_size);
611 if (r < 0)
612 return r;
613
614 r = synic_set_irq(synic, sint);
615 if (r < 0)
616 return r;
617 if (r == 0)
618 return -EFAULT;
619 return 0;
620 }
621
622 static int stimer_send_msg(struct kvm_vcpu_hv_stimer *stimer)
623 {
624 struct kvm_vcpu *vcpu = stimer_to_vcpu(stimer);
625 struct hv_message *msg = &stimer->msg;
626 struct hv_timer_message_payload *payload =
627 (struct hv_timer_message_payload *)&msg->u.payload;
628
629 /*
630 * To avoid piling up periodic ticks, don't retry message
631 * delivery for them (within "lazy" lost ticks policy).
632 */
633 bool no_retry = stimer->config.periodic;
634
635 payload->expiration_time = stimer->exp_time;
636 payload->delivery_time = get_time_ref_counter(vcpu->kvm);
637 return synic_deliver_msg(vcpu_to_synic(vcpu),
638 stimer->config.sintx, msg,
639 no_retry);
640 }
641
642 static int stimer_notify_direct(struct kvm_vcpu_hv_stimer *stimer)
643 {
644 struct kvm_vcpu *vcpu = stimer_to_vcpu(stimer);
645 struct kvm_lapic_irq irq = {
646 .delivery_mode = APIC_DM_FIXED,
647 .vector = stimer->config.apic_vector
648 };
649
650 if (lapic_in_kernel(vcpu))
651 return !kvm_apic_set_irq(vcpu, &irq, NULL);
652 return 0;
653 }
654
655 static void stimer_expiration(struct kvm_vcpu_hv_stimer *stimer)
656 {
657 int r, direct = stimer->config.direct_mode;
658
659 stimer->msg_pending = true;
660 if (!direct)
661 r = stimer_send_msg(stimer);
662 else
663 r = stimer_notify_direct(stimer);
664 trace_kvm_hv_stimer_expiration(stimer_to_vcpu(stimer)->vcpu_id,
665 stimer->index, direct, r);
666 if (!r) {
667 stimer->msg_pending = false;
668 if (!(stimer->config.periodic))
669 stimer->config.enable = 0;
670 }
671 }
672
673 void kvm_hv_process_stimers(struct kvm_vcpu *vcpu)
674 {
675 struct kvm_vcpu_hv *hv_vcpu = vcpu_to_hv_vcpu(vcpu);
676 struct kvm_vcpu_hv_stimer *stimer;
677 u64 time_now, exp_time;
678 int i;
679
680 for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++)
681 if (test_and_clear_bit(i, hv_vcpu->stimer_pending_bitmap)) {
682 stimer = &hv_vcpu->stimer[i];
683 if (stimer->config.enable) {
684 exp_time = stimer->exp_time;
685
686 if (exp_time) {
687 time_now =
688 get_time_ref_counter(vcpu->kvm);
689 if (time_now >= exp_time)
690 stimer_expiration(stimer);
691 }
692
693 if ((stimer->config.enable) &&
694 stimer->count) {
695 if (!stimer->msg_pending)
696 stimer_start(stimer);
697 } else
698 stimer_cleanup(stimer);
699 }
700 }
701 }
702
703 void kvm_hv_vcpu_uninit(struct kvm_vcpu *vcpu)
704 {
705 struct kvm_vcpu_hv *hv_vcpu = vcpu_to_hv_vcpu(vcpu);
706 int i;
707
708 for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++)
709 stimer_cleanup(&hv_vcpu->stimer[i]);
710 }
711
712 bool kvm_hv_assist_page_enabled(struct kvm_vcpu *vcpu)
713 {
714 if (!(vcpu->arch.hyperv.hv_vapic & HV_X64_MSR_VP_ASSIST_PAGE_ENABLE))
715 return false;
716 return vcpu->arch.pv_eoi.msr_val & KVM_MSR_ENABLED;
717 }
718 EXPORT_SYMBOL_GPL(kvm_hv_assist_page_enabled);
719
720 bool kvm_hv_get_assist_page(struct kvm_vcpu *vcpu,
721 struct hv_vp_assist_page *assist_page)
722 {
723 if (!kvm_hv_assist_page_enabled(vcpu))
724 return false;
725 return !kvm_read_guest_cached(vcpu->kvm, &vcpu->arch.pv_eoi.data,
726 assist_page, sizeof(*assist_page));
727 }
728 EXPORT_SYMBOL_GPL(kvm_hv_get_assist_page);
729
730 static void stimer_prepare_msg(struct kvm_vcpu_hv_stimer *stimer)
731 {
732 struct hv_message *msg = &stimer->msg;
733 struct hv_timer_message_payload *payload =
734 (struct hv_timer_message_payload *)&msg->u.payload;
735
736 memset(&msg->header, 0, sizeof(msg->header));
737 msg->header.message_type = HVMSG_TIMER_EXPIRED;
738 msg->header.payload_size = sizeof(*payload);
739
740 payload->timer_index = stimer->index;
741 payload->expiration_time = 0;
742 payload->delivery_time = 0;
743 }
744
745 static void stimer_init(struct kvm_vcpu_hv_stimer *stimer, int timer_index)
746 {
747 memset(stimer, 0, sizeof(*stimer));
748 stimer->index = timer_index;
749 hrtimer_init(&stimer->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
750 stimer->timer.function = stimer_timer_callback;
751 stimer_prepare_msg(stimer);
752 }
753
754 void kvm_hv_vcpu_init(struct kvm_vcpu *vcpu)
755 {
756 struct kvm_vcpu_hv *hv_vcpu = vcpu_to_hv_vcpu(vcpu);
757 int i;
758
759 synic_init(&hv_vcpu->synic);
760
761 bitmap_zero(hv_vcpu->stimer_pending_bitmap, HV_SYNIC_STIMER_COUNT);
762 for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++)
763 stimer_init(&hv_vcpu->stimer[i], i);
764 }
765
766 void kvm_hv_vcpu_postcreate(struct kvm_vcpu *vcpu)
767 {
768 struct kvm_vcpu_hv *hv_vcpu = vcpu_to_hv_vcpu(vcpu);
769
770 hv_vcpu->vp_index = kvm_vcpu_get_idx(vcpu);
771 }
772
773 int kvm_hv_activate_synic(struct kvm_vcpu *vcpu, bool dont_zero_synic_pages)
774 {
775 struct kvm_vcpu_hv_synic *synic = vcpu_to_synic(vcpu);
776
777 /*
778 * Hyper-V SynIC auto EOI SINT's are
779 * not compatible with APICV, so request
780 * to deactivate APICV permanently.
781 */
782 kvm_request_apicv_update(vcpu->kvm, false, APICV_INHIBIT_REASON_HYPERV);
783 synic->active = true;
784 synic->dont_zero_synic_pages = dont_zero_synic_pages;
785 return 0;
786 }
787
788 static bool kvm_hv_msr_partition_wide(u32 msr)
789 {
790 bool r = false;
791
792 switch (msr) {
793 case HV_X64_MSR_GUEST_OS_ID:
794 case HV_X64_MSR_HYPERCALL:
795 case HV_X64_MSR_REFERENCE_TSC:
796 case HV_X64_MSR_TIME_REF_COUNT:
797 case HV_X64_MSR_CRASH_CTL:
798 case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
799 case HV_X64_MSR_RESET:
800 case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
801 case HV_X64_MSR_TSC_EMULATION_CONTROL:
802 case HV_X64_MSR_TSC_EMULATION_STATUS:
803 r = true;
804 break;
805 }
806
807 return r;
808 }
809
810 static int kvm_hv_msr_get_crash_data(struct kvm_vcpu *vcpu,
811 u32 index, u64 *pdata)
812 {
813 struct kvm_hv *hv = &vcpu->kvm->arch.hyperv;
814 size_t size = ARRAY_SIZE(hv->hv_crash_param);
815
816 if (WARN_ON_ONCE(index >= size))
817 return -EINVAL;
818
819 *pdata = hv->hv_crash_param[array_index_nospec(index, size)];
820 return 0;
821 }
822
823 static int kvm_hv_msr_get_crash_ctl(struct kvm_vcpu *vcpu, u64 *pdata)
824 {
825 struct kvm_hv *hv = &vcpu->kvm->arch.hyperv;
826
827 *pdata = hv->hv_crash_ctl;
828 return 0;
829 }
830
831 static int kvm_hv_msr_set_crash_ctl(struct kvm_vcpu *vcpu, u64 data, bool host)
832 {
833 struct kvm_hv *hv = &vcpu->kvm->arch.hyperv;
834
835 if (host)
836 hv->hv_crash_ctl = data & HV_CRASH_CTL_CRASH_NOTIFY;
837
838 if (!host && (data & HV_CRASH_CTL_CRASH_NOTIFY)) {
839
840 vcpu_debug(vcpu, "hv crash (0x%llx 0x%llx 0x%llx 0x%llx 0x%llx)\n",
841 hv->hv_crash_param[0],
842 hv->hv_crash_param[1],
843 hv->hv_crash_param[2],
844 hv->hv_crash_param[3],
845 hv->hv_crash_param[4]);
846
847 /* Send notification about crash to user space */
848 kvm_make_request(KVM_REQ_HV_CRASH, vcpu);
849 }
850
851 return 0;
852 }
853
854 static int kvm_hv_msr_set_crash_data(struct kvm_vcpu *vcpu,
855 u32 index, u64 data)
856 {
857 struct kvm_hv *hv = &vcpu->kvm->arch.hyperv;
858 size_t size = ARRAY_SIZE(hv->hv_crash_param);
859
860 if (WARN_ON_ONCE(index >= size))
861 return -EINVAL;
862
863 hv->hv_crash_param[array_index_nospec(index, size)] = data;
864 return 0;
865 }
866
867 /*
868 * The kvmclock and Hyper-V TSC page use similar formulas, and converting
869 * between them is possible:
870 *
871 * kvmclock formula:
872 * nsec = (ticks - tsc_timestamp) * tsc_to_system_mul * 2^(tsc_shift-32)
873 * + system_time
874 *
875 * Hyper-V formula:
876 * nsec/100 = ticks * scale / 2^64 + offset
877 *
878 * When tsc_timestamp = system_time = 0, offset is zero in the Hyper-V formula.
879 * By dividing the kvmclock formula by 100 and equating what's left we get:
880 * ticks * scale / 2^64 = ticks * tsc_to_system_mul * 2^(tsc_shift-32) / 100
881 * scale / 2^64 = tsc_to_system_mul * 2^(tsc_shift-32) / 100
882 * scale = tsc_to_system_mul * 2^(32+tsc_shift) / 100
883 *
884 * Now expand the kvmclock formula and divide by 100:
885 * nsec = ticks * tsc_to_system_mul * 2^(tsc_shift-32)
886 * - tsc_timestamp * tsc_to_system_mul * 2^(tsc_shift-32)
887 * + system_time
888 * nsec/100 = ticks * tsc_to_system_mul * 2^(tsc_shift-32) / 100
889 * - tsc_timestamp * tsc_to_system_mul * 2^(tsc_shift-32) / 100
890 * + system_time / 100
891 *
892 * Replace tsc_to_system_mul * 2^(tsc_shift-32) / 100 by scale / 2^64:
893 * nsec/100 = ticks * scale / 2^64
894 * - tsc_timestamp * scale / 2^64
895 * + system_time / 100
896 *
897 * Equate with the Hyper-V formula so that ticks * scale / 2^64 cancels out:
898 * offset = system_time / 100 - tsc_timestamp * scale / 2^64
899 *
900 * These two equivalencies are implemented in this function.
901 */
902 static bool compute_tsc_page_parameters(struct pvclock_vcpu_time_info *hv_clock,
903 HV_REFERENCE_TSC_PAGE *tsc_ref)
904 {
905 u64 max_mul;
906
907 if (!(hv_clock->flags & PVCLOCK_TSC_STABLE_BIT))
908 return false;
909
910 /*
911 * check if scale would overflow, if so we use the time ref counter
912 * tsc_to_system_mul * 2^(tsc_shift+32) / 100 >= 2^64
913 * tsc_to_system_mul / 100 >= 2^(32-tsc_shift)
914 * tsc_to_system_mul >= 100 * 2^(32-tsc_shift)
915 */
916 max_mul = 100ull << (32 - hv_clock->tsc_shift);
917 if (hv_clock->tsc_to_system_mul >= max_mul)
918 return false;
919
920 /*
921 * Otherwise compute the scale and offset according to the formulas
922 * derived above.
923 */
924 tsc_ref->tsc_scale =
925 mul_u64_u32_div(1ULL << (32 + hv_clock->tsc_shift),
926 hv_clock->tsc_to_system_mul,
927 100);
928
929 tsc_ref->tsc_offset = hv_clock->system_time;
930 do_div(tsc_ref->tsc_offset, 100);
931 tsc_ref->tsc_offset -=
932 mul_u64_u64_shr(hv_clock->tsc_timestamp, tsc_ref->tsc_scale, 64);
933 return true;
934 }
935
936 void kvm_hv_setup_tsc_page(struct kvm *kvm,
937 struct pvclock_vcpu_time_info *hv_clock)
938 {
939 struct kvm_hv *hv = &kvm->arch.hyperv;
940 u32 tsc_seq;
941 u64 gfn;
942
943 BUILD_BUG_ON(sizeof(tsc_seq) != sizeof(hv->tsc_ref.tsc_sequence));
944 BUILD_BUG_ON(offsetof(HV_REFERENCE_TSC_PAGE, tsc_sequence) != 0);
945
946 if (!(hv->hv_tsc_page & HV_X64_MSR_TSC_REFERENCE_ENABLE))
947 return;
948
949 mutex_lock(&kvm->arch.hyperv.hv_lock);
950 if (!(hv->hv_tsc_page & HV_X64_MSR_TSC_REFERENCE_ENABLE))
951 goto out_unlock;
952
953 gfn = hv->hv_tsc_page >> HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT;
954 /*
955 * Because the TSC parameters only vary when there is a
956 * change in the master clock, do not bother with caching.
957 */
958 if (unlikely(kvm_read_guest(kvm, gfn_to_gpa(gfn),
959 &tsc_seq, sizeof(tsc_seq))))
960 goto out_unlock;
961
962 /*
963 * While we're computing and writing the parameters, force the
964 * guest to use the time reference count MSR.
965 */
966 hv->tsc_ref.tsc_sequence = 0;
967 if (kvm_write_guest(kvm, gfn_to_gpa(gfn),
968 &hv->tsc_ref, sizeof(hv->tsc_ref.tsc_sequence)))
969 goto out_unlock;
970
971 if (!compute_tsc_page_parameters(hv_clock, &hv->tsc_ref))
972 goto out_unlock;
973
974 /* Ensure sequence is zero before writing the rest of the struct. */
975 smp_wmb();
976 if (kvm_write_guest(kvm, gfn_to_gpa(gfn), &hv->tsc_ref, sizeof(hv->tsc_ref)))
977 goto out_unlock;
978
979 /*
980 * Now switch to the TSC page mechanism by writing the sequence.
981 */
982 tsc_seq++;
983 if (tsc_seq == 0xFFFFFFFF || tsc_seq == 0)
984 tsc_seq = 1;
985
986 /* Write the struct entirely before the non-zero sequence. */
987 smp_wmb();
988
989 hv->tsc_ref.tsc_sequence = tsc_seq;
990 kvm_write_guest(kvm, gfn_to_gpa(gfn),
991 &hv->tsc_ref, sizeof(hv->tsc_ref.tsc_sequence));
992 out_unlock:
993 mutex_unlock(&kvm->arch.hyperv.hv_lock);
994 }
995
996 static int kvm_hv_set_msr_pw(struct kvm_vcpu *vcpu, u32 msr, u64 data,
997 bool host)
998 {
999 struct kvm *kvm = vcpu->kvm;
1000 struct kvm_hv *hv = &kvm->arch.hyperv;
1001
1002 switch (msr) {
1003 case HV_X64_MSR_GUEST_OS_ID:
1004 hv->hv_guest_os_id = data;
1005 /* setting guest os id to zero disables hypercall page */
1006 if (!hv->hv_guest_os_id)
1007 hv->hv_hypercall &= ~HV_X64_MSR_HYPERCALL_ENABLE;
1008 break;
1009 case HV_X64_MSR_HYPERCALL: {
1010 u64 gfn;
1011 unsigned long addr;
1012 u8 instructions[4];
1013
1014 /* if guest os id is not set hypercall should remain disabled */
1015 if (!hv->hv_guest_os_id)
1016 break;
1017 if (!(data & HV_X64_MSR_HYPERCALL_ENABLE)) {
1018 hv->hv_hypercall = data;
1019 break;
1020 }
1021 gfn = data >> HV_X64_MSR_HYPERCALL_PAGE_ADDRESS_SHIFT;
1022 addr = gfn_to_hva(kvm, gfn);
1023 if (kvm_is_error_hva(addr))
1024 return 1;
1025 kvm_x86_ops.patch_hypercall(vcpu, instructions);
1026 ((unsigned char *)instructions)[3] = 0xc3; /* ret */
1027 if (__copy_to_user((void __user *)addr, instructions, 4))
1028 return 1;
1029 hv->hv_hypercall = data;
1030 mark_page_dirty(kvm, gfn);
1031 break;
1032 }
1033 case HV_X64_MSR_REFERENCE_TSC:
1034 hv->hv_tsc_page = data;
1035 if (hv->hv_tsc_page & HV_X64_MSR_TSC_REFERENCE_ENABLE)
1036 kvm_make_request(KVM_REQ_MASTERCLOCK_UPDATE, vcpu);
1037 break;
1038 case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
1039 return kvm_hv_msr_set_crash_data(vcpu,
1040 msr - HV_X64_MSR_CRASH_P0,
1041 data);
1042 case HV_X64_MSR_CRASH_CTL:
1043 return kvm_hv_msr_set_crash_ctl(vcpu, data, host);
1044 case HV_X64_MSR_RESET:
1045 if (data == 1) {
1046 vcpu_debug(vcpu, "hyper-v reset requested\n");
1047 kvm_make_request(KVM_REQ_HV_RESET, vcpu);
1048 }
1049 break;
1050 case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
1051 hv->hv_reenlightenment_control = data;
1052 break;
1053 case HV_X64_MSR_TSC_EMULATION_CONTROL:
1054 hv->hv_tsc_emulation_control = data;
1055 break;
1056 case HV_X64_MSR_TSC_EMULATION_STATUS:
1057 hv->hv_tsc_emulation_status = data;
1058 break;
1059 case HV_X64_MSR_TIME_REF_COUNT:
1060 /* read-only, but still ignore it if host-initiated */
1061 if (!host)
1062 return 1;
1063 break;
1064 default:
1065 vcpu_unimpl(vcpu, "Hyper-V unhandled wrmsr: 0x%x data 0x%llx\n",
1066 msr, data);
1067 return 1;
1068 }
1069 return 0;
1070 }
1071
1072 /* Calculate cpu time spent by current task in 100ns units */
1073 static u64 current_task_runtime_100ns(void)
1074 {
1075 u64 utime, stime;
1076
1077 task_cputime_adjusted(current, &utime, &stime);
1078
1079 return div_u64(utime + stime, 100);
1080 }
1081
1082 static int kvm_hv_set_msr(struct kvm_vcpu *vcpu, u32 msr, u64 data, bool host)
1083 {
1084 struct kvm_vcpu_hv *hv_vcpu = &vcpu->arch.hyperv;
1085
1086 switch (msr) {
1087 case HV_X64_MSR_VP_INDEX: {
1088 struct kvm_hv *hv = &vcpu->kvm->arch.hyperv;
1089 int vcpu_idx = kvm_vcpu_get_idx(vcpu);
1090 u32 new_vp_index = (u32)data;
1091
1092 if (!host || new_vp_index >= KVM_MAX_VCPUS)
1093 return 1;
1094
1095 if (new_vp_index == hv_vcpu->vp_index)
1096 return 0;
1097
1098 /*
1099 * The VP index is initialized to vcpu_index by
1100 * kvm_hv_vcpu_postcreate so they initially match. Now the
1101 * VP index is changing, adjust num_mismatched_vp_indexes if
1102 * it now matches or no longer matches vcpu_idx.
1103 */
1104 if (hv_vcpu->vp_index == vcpu_idx)
1105 atomic_inc(&hv->num_mismatched_vp_indexes);
1106 else if (new_vp_index == vcpu_idx)
1107 atomic_dec(&hv->num_mismatched_vp_indexes);
1108
1109 hv_vcpu->vp_index = new_vp_index;
1110 break;
1111 }
1112 case HV_X64_MSR_VP_ASSIST_PAGE: {
1113 u64 gfn;
1114 unsigned long addr;
1115
1116 if (!(data & HV_X64_MSR_VP_ASSIST_PAGE_ENABLE)) {
1117 hv_vcpu->hv_vapic = data;
1118 if (kvm_lapic_enable_pv_eoi(vcpu, 0, 0))
1119 return 1;
1120 break;
1121 }
1122 gfn = data >> HV_X64_MSR_VP_ASSIST_PAGE_ADDRESS_SHIFT;
1123 addr = kvm_vcpu_gfn_to_hva(vcpu, gfn);
1124 if (kvm_is_error_hva(addr))
1125 return 1;
1126
1127 /*
1128 * Clear apic_assist portion of struct hv_vp_assist_page
1129 * only, there can be valuable data in the rest which needs
1130 * to be preserved e.g. on migration.
1131 */
1132 if (__clear_user((void __user *)addr, sizeof(u32)))
1133 return 1;
1134 hv_vcpu->hv_vapic = data;
1135 kvm_vcpu_mark_page_dirty(vcpu, gfn);
1136 if (kvm_lapic_enable_pv_eoi(vcpu,
1137 gfn_to_gpa(gfn) | KVM_MSR_ENABLED,
1138 sizeof(struct hv_vp_assist_page)))
1139 return 1;
1140 break;
1141 }
1142 case HV_X64_MSR_EOI:
1143 return kvm_hv_vapic_msr_write(vcpu, APIC_EOI, data);
1144 case HV_X64_MSR_ICR:
1145 return kvm_hv_vapic_msr_write(vcpu, APIC_ICR, data);
1146 case HV_X64_MSR_TPR:
1147 return kvm_hv_vapic_msr_write(vcpu, APIC_TASKPRI, data);
1148 case HV_X64_MSR_VP_RUNTIME:
1149 if (!host)
1150 return 1;
1151 hv_vcpu->runtime_offset = data - current_task_runtime_100ns();
1152 break;
1153 case HV_X64_MSR_SCONTROL:
1154 case HV_X64_MSR_SVERSION:
1155 case HV_X64_MSR_SIEFP:
1156 case HV_X64_MSR_SIMP:
1157 case HV_X64_MSR_EOM:
1158 case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
1159 return synic_set_msr(vcpu_to_synic(vcpu), msr, data, host);
1160 case HV_X64_MSR_STIMER0_CONFIG:
1161 case HV_X64_MSR_STIMER1_CONFIG:
1162 case HV_X64_MSR_STIMER2_CONFIG:
1163 case HV_X64_MSR_STIMER3_CONFIG: {
1164 int timer_index = (msr - HV_X64_MSR_STIMER0_CONFIG)/2;
1165
1166 return stimer_set_config(vcpu_to_stimer(vcpu, timer_index),
1167 data, host);
1168 }
1169 case HV_X64_MSR_STIMER0_COUNT:
1170 case HV_X64_MSR_STIMER1_COUNT:
1171 case HV_X64_MSR_STIMER2_COUNT:
1172 case HV_X64_MSR_STIMER3_COUNT: {
1173 int timer_index = (msr - HV_X64_MSR_STIMER0_COUNT)/2;
1174
1175 return stimer_set_count(vcpu_to_stimer(vcpu, timer_index),
1176 data, host);
1177 }
1178 case HV_X64_MSR_TSC_FREQUENCY:
1179 case HV_X64_MSR_APIC_FREQUENCY:
1180 /* read-only, but still ignore it if host-initiated */
1181 if (!host)
1182 return 1;
1183 break;
1184 default:
1185 vcpu_unimpl(vcpu, "Hyper-V unhandled wrmsr: 0x%x data 0x%llx\n",
1186 msr, data);
1187 return 1;
1188 }
1189
1190 return 0;
1191 }
1192
1193 static int kvm_hv_get_msr_pw(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata)
1194 {
1195 u64 data = 0;
1196 struct kvm *kvm = vcpu->kvm;
1197 struct kvm_hv *hv = &kvm->arch.hyperv;
1198
1199 switch (msr) {
1200 case HV_X64_MSR_GUEST_OS_ID:
1201 data = hv->hv_guest_os_id;
1202 break;
1203 case HV_X64_MSR_HYPERCALL:
1204 data = hv->hv_hypercall;
1205 break;
1206 case HV_X64_MSR_TIME_REF_COUNT:
1207 data = get_time_ref_counter(kvm);
1208 break;
1209 case HV_X64_MSR_REFERENCE_TSC:
1210 data = hv->hv_tsc_page;
1211 break;
1212 case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
1213 return kvm_hv_msr_get_crash_data(vcpu,
1214 msr - HV_X64_MSR_CRASH_P0,
1215 pdata);
1216 case HV_X64_MSR_CRASH_CTL:
1217 return kvm_hv_msr_get_crash_ctl(vcpu, pdata);
1218 case HV_X64_MSR_RESET:
1219 data = 0;
1220 break;
1221 case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
1222 data = hv->hv_reenlightenment_control;
1223 break;
1224 case HV_X64_MSR_TSC_EMULATION_CONTROL:
1225 data = hv->hv_tsc_emulation_control;
1226 break;
1227 case HV_X64_MSR_TSC_EMULATION_STATUS:
1228 data = hv->hv_tsc_emulation_status;
1229 break;
1230 default:
1231 vcpu_unimpl(vcpu, "Hyper-V unhandled rdmsr: 0x%x\n", msr);
1232 return 1;
1233 }
1234
1235 *pdata = data;
1236 return 0;
1237 }
1238
1239 static int kvm_hv_get_msr(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata,
1240 bool host)
1241 {
1242 u64 data = 0;
1243 struct kvm_vcpu_hv *hv_vcpu = &vcpu->arch.hyperv;
1244
1245 switch (msr) {
1246 case HV_X64_MSR_VP_INDEX:
1247 data = hv_vcpu->vp_index;
1248 break;
1249 case HV_X64_MSR_EOI:
1250 return kvm_hv_vapic_msr_read(vcpu, APIC_EOI, pdata);
1251 case HV_X64_MSR_ICR:
1252 return kvm_hv_vapic_msr_read(vcpu, APIC_ICR, pdata);
1253 case HV_X64_MSR_TPR:
1254 return kvm_hv_vapic_msr_read(vcpu, APIC_TASKPRI, pdata);
1255 case HV_X64_MSR_VP_ASSIST_PAGE:
1256 data = hv_vcpu->hv_vapic;
1257 break;
1258 case HV_X64_MSR_VP_RUNTIME:
1259 data = current_task_runtime_100ns() + hv_vcpu->runtime_offset;
1260 break;
1261 case HV_X64_MSR_SCONTROL:
1262 case HV_X64_MSR_SVERSION:
1263 case HV_X64_MSR_SIEFP:
1264 case HV_X64_MSR_SIMP:
1265 case HV_X64_MSR_EOM:
1266 case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
1267 return synic_get_msr(vcpu_to_synic(vcpu), msr, pdata, host);
1268 case HV_X64_MSR_STIMER0_CONFIG:
1269 case HV_X64_MSR_STIMER1_CONFIG:
1270 case HV_X64_MSR_STIMER2_CONFIG:
1271 case HV_X64_MSR_STIMER3_CONFIG: {
1272 int timer_index = (msr - HV_X64_MSR_STIMER0_CONFIG)/2;
1273
1274 return stimer_get_config(vcpu_to_stimer(vcpu, timer_index),
1275 pdata);
1276 }
1277 case HV_X64_MSR_STIMER0_COUNT:
1278 case HV_X64_MSR_STIMER1_COUNT:
1279 case HV_X64_MSR_STIMER2_COUNT:
1280 case HV_X64_MSR_STIMER3_COUNT: {
1281 int timer_index = (msr - HV_X64_MSR_STIMER0_COUNT)/2;
1282
1283 return stimer_get_count(vcpu_to_stimer(vcpu, timer_index),
1284 pdata);
1285 }
1286 case HV_X64_MSR_TSC_FREQUENCY:
1287 data = (u64)vcpu->arch.virtual_tsc_khz * 1000;
1288 break;
1289 case HV_X64_MSR_APIC_FREQUENCY:
1290 data = APIC_BUS_FREQUENCY;
1291 break;
1292 default:
1293 vcpu_unimpl(vcpu, "Hyper-V unhandled rdmsr: 0x%x\n", msr);
1294 return 1;
1295 }
1296 *pdata = data;
1297 return 0;
1298 }
1299
1300 int kvm_hv_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data, bool host)
1301 {
1302 if (kvm_hv_msr_partition_wide(msr)) {
1303 int r;
1304
1305 mutex_lock(&vcpu->kvm->arch.hyperv.hv_lock);
1306 r = kvm_hv_set_msr_pw(vcpu, msr, data, host);
1307 mutex_unlock(&vcpu->kvm->arch.hyperv.hv_lock);
1308 return r;
1309 } else
1310 return kvm_hv_set_msr(vcpu, msr, data, host);
1311 }
1312
1313 int kvm_hv_get_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata, bool host)
1314 {
1315 if (kvm_hv_msr_partition_wide(msr)) {
1316 int r;
1317
1318 mutex_lock(&vcpu->kvm->arch.hyperv.hv_lock);
1319 r = kvm_hv_get_msr_pw(vcpu, msr, pdata);
1320 mutex_unlock(&vcpu->kvm->arch.hyperv.hv_lock);
1321 return r;
1322 } else
1323 return kvm_hv_get_msr(vcpu, msr, pdata, host);
1324 }
1325
1326 static __always_inline unsigned long *sparse_set_to_vcpu_mask(
1327 struct kvm *kvm, u64 *sparse_banks, u64 valid_bank_mask,
1328 u64 *vp_bitmap, unsigned long *vcpu_bitmap)
1329 {
1330 struct kvm_hv *hv = &kvm->arch.hyperv;
1331 struct kvm_vcpu *vcpu;
1332 int i, bank, sbank = 0;
1333
1334 memset(vp_bitmap, 0,
1335 KVM_HV_MAX_SPARSE_VCPU_SET_BITS * sizeof(*vp_bitmap));
1336 for_each_set_bit(bank, (unsigned long *)&valid_bank_mask,
1337 KVM_HV_MAX_SPARSE_VCPU_SET_BITS)
1338 vp_bitmap[bank] = sparse_banks[sbank++];
1339
1340 if (likely(!atomic_read(&hv->num_mismatched_vp_indexes))) {
1341 /* for all vcpus vp_index == vcpu_idx */
1342 return (unsigned long *)vp_bitmap;
1343 }
1344
1345 bitmap_zero(vcpu_bitmap, KVM_MAX_VCPUS);
1346 kvm_for_each_vcpu(i, vcpu, kvm) {
1347 if (test_bit(vcpu_to_hv_vcpu(vcpu)->vp_index,
1348 (unsigned long *)vp_bitmap))
1349 __set_bit(i, vcpu_bitmap);
1350 }
1351 return vcpu_bitmap;
1352 }
1353
1354 static u64 kvm_hv_flush_tlb(struct kvm_vcpu *current_vcpu, u64 ingpa,
1355 u16 rep_cnt, bool ex)
1356 {
1357 struct kvm *kvm = current_vcpu->kvm;
1358 struct kvm_vcpu_hv *hv_vcpu = &current_vcpu->arch.hyperv;
1359 struct hv_tlb_flush_ex flush_ex;
1360 struct hv_tlb_flush flush;
1361 u64 vp_bitmap[KVM_HV_MAX_SPARSE_VCPU_SET_BITS];
1362 DECLARE_BITMAP(vcpu_bitmap, KVM_MAX_VCPUS);
1363 unsigned long *vcpu_mask;
1364 u64 valid_bank_mask;
1365 u64 sparse_banks[64];
1366 int sparse_banks_len;
1367 bool all_cpus;
1368
1369 if (!ex) {
1370 if (unlikely(kvm_read_guest(kvm, ingpa, &flush, sizeof(flush))))
1371 return HV_STATUS_INVALID_HYPERCALL_INPUT;
1372
1373 trace_kvm_hv_flush_tlb(flush.processor_mask,
1374 flush.address_space, flush.flags);
1375
1376 valid_bank_mask = BIT_ULL(0);
1377 sparse_banks[0] = flush.processor_mask;
1378
1379 /*
1380 * Work around possible WS2012 bug: it sends hypercalls
1381 * with processor_mask = 0x0 and HV_FLUSH_ALL_PROCESSORS clear,
1382 * while also expecting us to flush something and crashing if
1383 * we don't. Let's treat processor_mask == 0 same as
1384 * HV_FLUSH_ALL_PROCESSORS.
1385 */
1386 all_cpus = (flush.flags & HV_FLUSH_ALL_PROCESSORS) ||
1387 flush.processor_mask == 0;
1388 } else {
1389 if (unlikely(kvm_read_guest(kvm, ingpa, &flush_ex,
1390 sizeof(flush_ex))))
1391 return HV_STATUS_INVALID_HYPERCALL_INPUT;
1392
1393 trace_kvm_hv_flush_tlb_ex(flush_ex.hv_vp_set.valid_bank_mask,
1394 flush_ex.hv_vp_set.format,
1395 flush_ex.address_space,
1396 flush_ex.flags);
1397
1398 valid_bank_mask = flush_ex.hv_vp_set.valid_bank_mask;
1399 all_cpus = flush_ex.hv_vp_set.format !=
1400 HV_GENERIC_SET_SPARSE_4K;
1401
1402 sparse_banks_len =
1403 bitmap_weight((unsigned long *)&valid_bank_mask, 64) *
1404 sizeof(sparse_banks[0]);
1405
1406 if (!sparse_banks_len && !all_cpus)
1407 goto ret_success;
1408
1409 if (!all_cpus &&
1410 kvm_read_guest(kvm,
1411 ingpa + offsetof(struct hv_tlb_flush_ex,
1412 hv_vp_set.bank_contents),
1413 sparse_banks,
1414 sparse_banks_len))
1415 return HV_STATUS_INVALID_HYPERCALL_INPUT;
1416 }
1417
1418 cpumask_clear(&hv_vcpu->tlb_flush);
1419
1420 vcpu_mask = all_cpus ? NULL :
1421 sparse_set_to_vcpu_mask(kvm, sparse_banks, valid_bank_mask,
1422 vp_bitmap, vcpu_bitmap);
1423
1424 /*
1425 * vcpu->arch.cr3 may not be up-to-date for running vCPUs so we can't
1426 * analyze it here, flush TLB regardless of the specified address space.
1427 */
1428 kvm_make_vcpus_request_mask(kvm,
1429 KVM_REQ_TLB_FLUSH | KVM_REQUEST_NO_WAKEUP,
1430 vcpu_mask, &hv_vcpu->tlb_flush);
1431
1432 ret_success:
1433 /* We always do full TLB flush, set rep_done = rep_cnt. */
1434 return (u64)HV_STATUS_SUCCESS |
1435 ((u64)rep_cnt << HV_HYPERCALL_REP_COMP_OFFSET);
1436 }
1437
1438 static void kvm_send_ipi_to_many(struct kvm *kvm, u32 vector,
1439 unsigned long *vcpu_bitmap)
1440 {
1441 struct kvm_lapic_irq irq = {
1442 .delivery_mode = APIC_DM_FIXED,
1443 .vector = vector
1444 };
1445 struct kvm_vcpu *vcpu;
1446 int i;
1447
1448 kvm_for_each_vcpu(i, vcpu, kvm) {
1449 if (vcpu_bitmap && !test_bit(i, vcpu_bitmap))
1450 continue;
1451
1452 /* We fail only when APIC is disabled */
1453 kvm_apic_set_irq(vcpu, &irq, NULL);
1454 }
1455 }
1456
1457 static u64 kvm_hv_send_ipi(struct kvm_vcpu *current_vcpu, u64 ingpa, u64 outgpa,
1458 bool ex, bool fast)
1459 {
1460 struct kvm *kvm = current_vcpu->kvm;
1461 struct hv_send_ipi_ex send_ipi_ex;
1462 struct hv_send_ipi send_ipi;
1463 u64 vp_bitmap[KVM_HV_MAX_SPARSE_VCPU_SET_BITS];
1464 DECLARE_BITMAP(vcpu_bitmap, KVM_MAX_VCPUS);
1465 unsigned long *vcpu_mask;
1466 unsigned long valid_bank_mask;
1467 u64 sparse_banks[64];
1468 int sparse_banks_len;
1469 u32 vector;
1470 bool all_cpus;
1471
1472 if (!ex) {
1473 if (!fast) {
1474 if (unlikely(kvm_read_guest(kvm, ingpa, &send_ipi,
1475 sizeof(send_ipi))))
1476 return HV_STATUS_INVALID_HYPERCALL_INPUT;
1477 sparse_banks[0] = send_ipi.cpu_mask;
1478 vector = send_ipi.vector;
1479 } else {
1480 /* 'reserved' part of hv_send_ipi should be 0 */
1481 if (unlikely(ingpa >> 32 != 0))
1482 return HV_STATUS_INVALID_HYPERCALL_INPUT;
1483 sparse_banks[0] = outgpa;
1484 vector = (u32)ingpa;
1485 }
1486 all_cpus = false;
1487 valid_bank_mask = BIT_ULL(0);
1488
1489 trace_kvm_hv_send_ipi(vector, sparse_banks[0]);
1490 } else {
1491 if (unlikely(kvm_read_guest(kvm, ingpa, &send_ipi_ex,
1492 sizeof(send_ipi_ex))))
1493 return HV_STATUS_INVALID_HYPERCALL_INPUT;
1494
1495 trace_kvm_hv_send_ipi_ex(send_ipi_ex.vector,
1496 send_ipi_ex.vp_set.format,
1497 send_ipi_ex.vp_set.valid_bank_mask);
1498
1499 vector = send_ipi_ex.vector;
1500 valid_bank_mask = send_ipi_ex.vp_set.valid_bank_mask;
1501 sparse_banks_len = bitmap_weight(&valid_bank_mask, 64) *
1502 sizeof(sparse_banks[0]);
1503
1504 all_cpus = send_ipi_ex.vp_set.format == HV_GENERIC_SET_ALL;
1505
1506 if (!sparse_banks_len)
1507 goto ret_success;
1508
1509 if (!all_cpus &&
1510 kvm_read_guest(kvm,
1511 ingpa + offsetof(struct hv_send_ipi_ex,
1512 vp_set.bank_contents),
1513 sparse_banks,
1514 sparse_banks_len))
1515 return HV_STATUS_INVALID_HYPERCALL_INPUT;
1516 }
1517
1518 if ((vector < HV_IPI_LOW_VECTOR) || (vector > HV_IPI_HIGH_VECTOR))
1519 return HV_STATUS_INVALID_HYPERCALL_INPUT;
1520
1521 vcpu_mask = all_cpus ? NULL :
1522 sparse_set_to_vcpu_mask(kvm, sparse_banks, valid_bank_mask,
1523 vp_bitmap, vcpu_bitmap);
1524
1525 kvm_send_ipi_to_many(kvm, vector, vcpu_mask);
1526
1527 ret_success:
1528 return HV_STATUS_SUCCESS;
1529 }
1530
1531 bool kvm_hv_hypercall_enabled(struct kvm *kvm)
1532 {
1533 return READ_ONCE(kvm->arch.hyperv.hv_hypercall) & HV_X64_MSR_HYPERCALL_ENABLE;
1534 }
1535
1536 static void kvm_hv_hypercall_set_result(struct kvm_vcpu *vcpu, u64 result)
1537 {
1538 bool longmode;
1539
1540 longmode = is_64_bit_mode(vcpu);
1541 if (longmode)
1542 kvm_rax_write(vcpu, result);
1543 else {
1544 kvm_rdx_write(vcpu, result >> 32);
1545 kvm_rax_write(vcpu, result & 0xffffffff);
1546 }
1547 }
1548
1549 static int kvm_hv_hypercall_complete(struct kvm_vcpu *vcpu, u64 result)
1550 {
1551 kvm_hv_hypercall_set_result(vcpu, result);
1552 ++vcpu->stat.hypercalls;
1553 return kvm_skip_emulated_instruction(vcpu);
1554 }
1555
1556 static int kvm_hv_hypercall_complete_userspace(struct kvm_vcpu *vcpu)
1557 {
1558 return kvm_hv_hypercall_complete(vcpu, vcpu->run->hyperv.u.hcall.result);
1559 }
1560
1561 static u16 kvm_hvcall_signal_event(struct kvm_vcpu *vcpu, bool fast, u64 param)
1562 {
1563 struct eventfd_ctx *eventfd;
1564
1565 if (unlikely(!fast)) {
1566 int ret;
1567 gpa_t gpa = param;
1568
1569 if ((gpa & (__alignof__(param) - 1)) ||
1570 offset_in_page(gpa) + sizeof(param) > PAGE_SIZE)
1571 return HV_STATUS_INVALID_ALIGNMENT;
1572
1573 ret = kvm_vcpu_read_guest(vcpu, gpa, &param, sizeof(param));
1574 if (ret < 0)
1575 return HV_STATUS_INVALID_ALIGNMENT;
1576 }
1577
1578 /*
1579 * Per spec, bits 32-47 contain the extra "flag number". However, we
1580 * have no use for it, and in all known usecases it is zero, so just
1581 * report lookup failure if it isn't.
1582 */
1583 if (param & 0xffff00000000ULL)
1584 return HV_STATUS_INVALID_PORT_ID;
1585 /* remaining bits are reserved-zero */
1586 if (param & ~KVM_HYPERV_CONN_ID_MASK)
1587 return HV_STATUS_INVALID_HYPERCALL_INPUT;
1588
1589 /* the eventfd is protected by vcpu->kvm->srcu, but conn_to_evt isn't */
1590 rcu_read_lock();
1591 eventfd = idr_find(&vcpu->kvm->arch.hyperv.conn_to_evt, param);
1592 rcu_read_unlock();
1593 if (!eventfd)
1594 return HV_STATUS_INVALID_PORT_ID;
1595
1596 eventfd_signal(eventfd, 1);
1597 return HV_STATUS_SUCCESS;
1598 }
1599
1600 int kvm_hv_hypercall(struct kvm_vcpu *vcpu)
1601 {
1602 u64 param, ingpa, outgpa, ret = HV_STATUS_SUCCESS;
1603 uint16_t code, rep_idx, rep_cnt;
1604 bool fast, rep;
1605
1606 /*
1607 * hypercall generates UD from non zero cpl and real mode
1608 * per HYPER-V spec
1609 */
1610 if (kvm_x86_ops.get_cpl(vcpu) != 0 || !is_protmode(vcpu)) {
1611 kvm_queue_exception(vcpu, UD_VECTOR);
1612 return 1;
1613 }
1614
1615 #ifdef CONFIG_X86_64
1616 if (is_64_bit_mode(vcpu)) {
1617 param = kvm_rcx_read(vcpu);
1618 ingpa = kvm_rdx_read(vcpu);
1619 outgpa = kvm_r8_read(vcpu);
1620 } else
1621 #endif
1622 {
1623 param = ((u64)kvm_rdx_read(vcpu) << 32) |
1624 (kvm_rax_read(vcpu) & 0xffffffff);
1625 ingpa = ((u64)kvm_rbx_read(vcpu) << 32) |
1626 (kvm_rcx_read(vcpu) & 0xffffffff);
1627 outgpa = ((u64)kvm_rdi_read(vcpu) << 32) |
1628 (kvm_rsi_read(vcpu) & 0xffffffff);
1629 }
1630
1631 code = param & 0xffff;
1632 fast = !!(param & HV_HYPERCALL_FAST_BIT);
1633 rep_cnt = (param >> HV_HYPERCALL_REP_COMP_OFFSET) & 0xfff;
1634 rep_idx = (param >> HV_HYPERCALL_REP_START_OFFSET) & 0xfff;
1635 rep = !!(rep_cnt || rep_idx);
1636
1637 trace_kvm_hv_hypercall(code, fast, rep_cnt, rep_idx, ingpa, outgpa);
1638
1639 switch (code) {
1640 case HVCALL_NOTIFY_LONG_SPIN_WAIT:
1641 if (unlikely(rep)) {
1642 ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
1643 break;
1644 }
1645 kvm_vcpu_on_spin(vcpu, true);
1646 break;
1647 case HVCALL_SIGNAL_EVENT:
1648 if (unlikely(rep)) {
1649 ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
1650 break;
1651 }
1652 ret = kvm_hvcall_signal_event(vcpu, fast, ingpa);
1653 if (ret != HV_STATUS_INVALID_PORT_ID)
1654 break;
1655 /* fall through - maybe userspace knows this conn_id. */
1656 case HVCALL_POST_MESSAGE:
1657 /* don't bother userspace if it has no way to handle it */
1658 if (unlikely(rep || !vcpu_to_synic(vcpu)->active)) {
1659 ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
1660 break;
1661 }
1662 vcpu->run->exit_reason = KVM_EXIT_HYPERV;
1663 vcpu->run->hyperv.type = KVM_EXIT_HYPERV_HCALL;
1664 vcpu->run->hyperv.u.hcall.input = param;
1665 vcpu->run->hyperv.u.hcall.params[0] = ingpa;
1666 vcpu->run->hyperv.u.hcall.params[1] = outgpa;
1667 vcpu->arch.complete_userspace_io =
1668 kvm_hv_hypercall_complete_userspace;
1669 return 0;
1670 case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST:
1671 if (unlikely(fast || !rep_cnt || rep_idx)) {
1672 ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
1673 break;
1674 }
1675 ret = kvm_hv_flush_tlb(vcpu, ingpa, rep_cnt, false);
1676 break;
1677 case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
1678 if (unlikely(fast || rep)) {
1679 ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
1680 break;
1681 }
1682 ret = kvm_hv_flush_tlb(vcpu, ingpa, rep_cnt, false);
1683 break;
1684 case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX:
1685 if (unlikely(fast || !rep_cnt || rep_idx)) {
1686 ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
1687 break;
1688 }
1689 ret = kvm_hv_flush_tlb(vcpu, ingpa, rep_cnt, true);
1690 break;
1691 case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX:
1692 if (unlikely(fast || rep)) {
1693 ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
1694 break;
1695 }
1696 ret = kvm_hv_flush_tlb(vcpu, ingpa, rep_cnt, true);
1697 break;
1698 case HVCALL_SEND_IPI:
1699 if (unlikely(rep)) {
1700 ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
1701 break;
1702 }
1703 ret = kvm_hv_send_ipi(vcpu, ingpa, outgpa, false, fast);
1704 break;
1705 case HVCALL_SEND_IPI_EX:
1706 if (unlikely(fast || rep)) {
1707 ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
1708 break;
1709 }
1710 ret = kvm_hv_send_ipi(vcpu, ingpa, outgpa, true, false);
1711 break;
1712 default:
1713 ret = HV_STATUS_INVALID_HYPERCALL_CODE;
1714 break;
1715 }
1716
1717 return kvm_hv_hypercall_complete(vcpu, ret);
1718 }
1719
1720 void kvm_hv_init_vm(struct kvm *kvm)
1721 {
1722 mutex_init(&kvm->arch.hyperv.hv_lock);
1723 idr_init(&kvm->arch.hyperv.conn_to_evt);
1724 }
1725
1726 void kvm_hv_destroy_vm(struct kvm *kvm)
1727 {
1728 struct eventfd_ctx *eventfd;
1729 int i;
1730
1731 idr_for_each_entry(&kvm->arch.hyperv.conn_to_evt, eventfd, i)
1732 eventfd_ctx_put(eventfd);
1733 idr_destroy(&kvm->arch.hyperv.conn_to_evt);
1734 }
1735
1736 static int kvm_hv_eventfd_assign(struct kvm *kvm, u32 conn_id, int fd)
1737 {
1738 struct kvm_hv *hv = &kvm->arch.hyperv;
1739 struct eventfd_ctx *eventfd;
1740 int ret;
1741
1742 eventfd = eventfd_ctx_fdget(fd);
1743 if (IS_ERR(eventfd))
1744 return PTR_ERR(eventfd);
1745
1746 mutex_lock(&hv->hv_lock);
1747 ret = idr_alloc(&hv->conn_to_evt, eventfd, conn_id, conn_id + 1,
1748 GFP_KERNEL_ACCOUNT);
1749 mutex_unlock(&hv->hv_lock);
1750
1751 if (ret >= 0)
1752 return 0;
1753
1754 if (ret == -ENOSPC)
1755 ret = -EEXIST;
1756 eventfd_ctx_put(eventfd);
1757 return ret;
1758 }
1759
1760 static int kvm_hv_eventfd_deassign(struct kvm *kvm, u32 conn_id)
1761 {
1762 struct kvm_hv *hv = &kvm->arch.hyperv;
1763 struct eventfd_ctx *eventfd;
1764
1765 mutex_lock(&hv->hv_lock);
1766 eventfd = idr_remove(&hv->conn_to_evt, conn_id);
1767 mutex_unlock(&hv->hv_lock);
1768
1769 if (!eventfd)
1770 return -ENOENT;
1771
1772 synchronize_srcu(&kvm->srcu);
1773 eventfd_ctx_put(eventfd);
1774 return 0;
1775 }
1776
1777 int kvm_vm_ioctl_hv_eventfd(struct kvm *kvm, struct kvm_hyperv_eventfd *args)
1778 {
1779 if ((args->flags & ~KVM_HYPERV_EVENTFD_DEASSIGN) ||
1780 (args->conn_id & ~KVM_HYPERV_CONN_ID_MASK))
1781 return -EINVAL;
1782
1783 if (args->flags == KVM_HYPERV_EVENTFD_DEASSIGN)
1784 return kvm_hv_eventfd_deassign(kvm, args->conn_id);
1785 return kvm_hv_eventfd_assign(kvm, args->conn_id, args->fd);
1786 }
1787
1788 int kvm_vcpu_ioctl_get_hv_cpuid(struct kvm_vcpu *vcpu, struct kvm_cpuid2 *cpuid,
1789 struct kvm_cpuid_entry2 __user *entries)
1790 {
1791 uint16_t evmcs_ver = 0;
1792 struct kvm_cpuid_entry2 cpuid_entries[] = {
1793 { .function = HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS },
1794 { .function = HYPERV_CPUID_INTERFACE },
1795 { .function = HYPERV_CPUID_VERSION },
1796 { .function = HYPERV_CPUID_FEATURES },
1797 { .function = HYPERV_CPUID_ENLIGHTMENT_INFO },
1798 { .function = HYPERV_CPUID_IMPLEMENT_LIMITS },
1799 { .function = HYPERV_CPUID_NESTED_FEATURES },
1800 };
1801 int i, nent = ARRAY_SIZE(cpuid_entries);
1802
1803 if (kvm_x86_ops.nested_get_evmcs_version)
1804 evmcs_ver = kvm_x86_ops.nested_get_evmcs_version(vcpu);
1805
1806 /* Skip NESTED_FEATURES if eVMCS is not supported */
1807 if (!evmcs_ver)
1808 --nent;
1809
1810 if (cpuid->nent < nent)
1811 return -E2BIG;
1812
1813 if (cpuid->nent > nent)
1814 cpuid->nent = nent;
1815
1816 for (i = 0; i < nent; i++) {
1817 struct kvm_cpuid_entry2 *ent = &cpuid_entries[i];
1818 u32 signature[3];
1819
1820 switch (ent->function) {
1821 case HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS:
1822 memcpy(signature, "Linux KVM Hv", 12);
1823
1824 ent->eax = HYPERV_CPUID_NESTED_FEATURES;
1825 ent->ebx = signature[0];
1826 ent->ecx = signature[1];
1827 ent->edx = signature[2];
1828 break;
1829
1830 case HYPERV_CPUID_INTERFACE:
1831 memcpy(signature, "Hv#1\0\0\0\0\0\0\0\0", 12);
1832 ent->eax = signature[0];
1833 break;
1834
1835 case HYPERV_CPUID_VERSION:
1836 /*
1837 * We implement some Hyper-V 2016 functions so let's use
1838 * this version.
1839 */
1840 ent->eax = 0x00003839;
1841 ent->ebx = 0x000A0000;
1842 break;
1843
1844 case HYPERV_CPUID_FEATURES:
1845 ent->eax |= HV_X64_MSR_VP_RUNTIME_AVAILABLE;
1846 ent->eax |= HV_MSR_TIME_REF_COUNT_AVAILABLE;
1847 ent->eax |= HV_X64_MSR_SYNIC_AVAILABLE;
1848 ent->eax |= HV_MSR_SYNTIMER_AVAILABLE;
1849 ent->eax |= HV_X64_MSR_APIC_ACCESS_AVAILABLE;
1850 ent->eax |= HV_X64_MSR_HYPERCALL_AVAILABLE;
1851 ent->eax |= HV_X64_MSR_VP_INDEX_AVAILABLE;
1852 ent->eax |= HV_X64_MSR_RESET_AVAILABLE;
1853 ent->eax |= HV_MSR_REFERENCE_TSC_AVAILABLE;
1854 ent->eax |= HV_X64_ACCESS_FREQUENCY_MSRS;
1855 ent->eax |= HV_X64_ACCESS_REENLIGHTENMENT;
1856
1857 ent->ebx |= HV_X64_POST_MESSAGES;
1858 ent->ebx |= HV_X64_SIGNAL_EVENTS;
1859
1860 ent->edx |= HV_FEATURE_FREQUENCY_MSRS_AVAILABLE;
1861 ent->edx |= HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE;
1862
1863 /*
1864 * Direct Synthetic timers only make sense with in-kernel
1865 * LAPIC
1866 */
1867 if (lapic_in_kernel(vcpu))
1868 ent->edx |= HV_STIMER_DIRECT_MODE_AVAILABLE;
1869
1870 break;
1871
1872 case HYPERV_CPUID_ENLIGHTMENT_INFO:
1873 ent->eax |= HV_X64_REMOTE_TLB_FLUSH_RECOMMENDED;
1874 ent->eax |= HV_X64_APIC_ACCESS_RECOMMENDED;
1875 ent->eax |= HV_X64_RELAXED_TIMING_RECOMMENDED;
1876 ent->eax |= HV_X64_CLUSTER_IPI_RECOMMENDED;
1877 ent->eax |= HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED;
1878 if (evmcs_ver)
1879 ent->eax |= HV_X64_ENLIGHTENED_VMCS_RECOMMENDED;
1880 if (!cpu_smt_possible())
1881 ent->eax |= HV_X64_NO_NONARCH_CORESHARING;
1882 /*
1883 * Default number of spinlock retry attempts, matches
1884 * HyperV 2016.
1885 */
1886 ent->ebx = 0x00000FFF;
1887
1888 break;
1889
1890 case HYPERV_CPUID_IMPLEMENT_LIMITS:
1891 /* Maximum number of virtual processors */
1892 ent->eax = KVM_MAX_VCPUS;
1893 /*
1894 * Maximum number of logical processors, matches
1895 * HyperV 2016.
1896 */
1897 ent->ebx = 64;
1898
1899 break;
1900
1901 case HYPERV_CPUID_NESTED_FEATURES:
1902 ent->eax = evmcs_ver;
1903
1904 break;
1905
1906 default:
1907 break;
1908 }
1909 }
1910
1911 if (copy_to_user(entries, cpuid_entries,
1912 nent * sizeof(struct kvm_cpuid_entry2)))
1913 return -EFAULT;
1914
1915 return 0;
1916 }