KVM: x86: fix #UD address of failed Hyper-V hypercalls
[muen/linux.git] / arch / x86 / kvm / hyperv.c
1 /*
2  * KVM Microsoft Hyper-V emulation
3  *
4  * derived from arch/x86/kvm/x86.c
5  *
6  * Copyright (C) 2006 Qumranet, Inc.
7  * Copyright (C) 2008 Qumranet, Inc.
8  * Copyright IBM Corporation, 2008
9  * Copyright 2010 Red Hat, Inc. and/or its affiliates.
10  * Copyright (C) 2015 Andrey Smetanin <asmetanin@virtuozzo.com>
11  *
12  * Authors:
13  *   Avi Kivity   <avi@qumranet.com>
14  *   Yaniv Kamay  <yaniv@qumranet.com>
15  *   Amit Shah    <amit.shah@qumranet.com>
16  *   Ben-Ami Yassour <benami@il.ibm.com>
17  *   Andrey Smetanin <asmetanin@virtuozzo.com>
18  *
19  * This work is licensed under the terms of the GNU GPL, version 2.  See
20  * the COPYING file in the top-level directory.
21  *
22  */
23
24 #include "x86.h"
25 #include "lapic.h"
26 #include "ioapic.h"
27 #include "hyperv.h"
28
29 #include <linux/kvm_host.h>
30 #include <linux/highmem.h>
31 #include <linux/sched/cputime.h>
32 #include <linux/eventfd.h>
33
34 #include <asm/apicdef.h>
35 #include <trace/events/kvm.h>
36
37 #include "trace.h"
38
39 static inline u64 synic_read_sint(struct kvm_vcpu_hv_synic *synic, int sint)
40 {
41         return atomic64_read(&synic->sint[sint]);
42 }
43
44 static inline int synic_get_sint_vector(u64 sint_value)
45 {
46         if (sint_value & HV_SYNIC_SINT_MASKED)
47                 return -1;
48         return sint_value & HV_SYNIC_SINT_VECTOR_MASK;
49 }
50
51 static bool synic_has_vector_connected(struct kvm_vcpu_hv_synic *synic,
52                                       int vector)
53 {
54         int i;
55
56         for (i = 0; i < ARRAY_SIZE(synic->sint); i++) {
57                 if (synic_get_sint_vector(synic_read_sint(synic, i)) == vector)
58                         return true;
59         }
60         return false;
61 }
62
63 static bool synic_has_vector_auto_eoi(struct kvm_vcpu_hv_synic *synic,
64                                      int vector)
65 {
66         int i;
67         u64 sint_value;
68
69         for (i = 0; i < ARRAY_SIZE(synic->sint); i++) {
70                 sint_value = synic_read_sint(synic, i);
71                 if (synic_get_sint_vector(sint_value) == vector &&
72                     sint_value & HV_SYNIC_SINT_AUTO_EOI)
73                         return true;
74         }
75         return false;
76 }
77
78 static void synic_update_vector(struct kvm_vcpu_hv_synic *synic,
79                                 int vector)
80 {
81         if (vector < HV_SYNIC_FIRST_VALID_VECTOR)
82                 return;
83
84         if (synic_has_vector_connected(synic, vector))
85                 __set_bit(vector, synic->vec_bitmap);
86         else
87                 __clear_bit(vector, synic->vec_bitmap);
88
89         if (synic_has_vector_auto_eoi(synic, vector))
90                 __set_bit(vector, synic->auto_eoi_bitmap);
91         else
92                 __clear_bit(vector, synic->auto_eoi_bitmap);
93 }
94
95 static int synic_set_sint(struct kvm_vcpu_hv_synic *synic, int sint,
96                           u64 data, bool host)
97 {
98         int vector, old_vector;
99         bool masked;
100
101         vector = data & HV_SYNIC_SINT_VECTOR_MASK;
102         masked = data & HV_SYNIC_SINT_MASKED;
103
104         /*
105          * Valid vectors are 16-255, however, nested Hyper-V attempts to write
106          * default '0x10000' value on boot and this should not #GP. We need to
107          * allow zero-initing the register from host as well.
108          */
109         if (vector < HV_SYNIC_FIRST_VALID_VECTOR && !host && !masked)
110                 return 1;
111         /*
112          * Guest may configure multiple SINTs to use the same vector, so
113          * we maintain a bitmap of vectors handled by synic, and a
114          * bitmap of vectors with auto-eoi behavior.  The bitmaps are
115          * updated here, and atomically queried on fast paths.
116          */
117         old_vector = synic_read_sint(synic, sint) & HV_SYNIC_SINT_VECTOR_MASK;
118
119         atomic64_set(&synic->sint[sint], data);
120
121         synic_update_vector(synic, old_vector);
122
123         synic_update_vector(synic, vector);
124
125         /* Load SynIC vectors into EOI exit bitmap */
126         kvm_make_request(KVM_REQ_SCAN_IOAPIC, synic_to_vcpu(synic));
127         return 0;
128 }
129
130 static struct kvm_vcpu *get_vcpu_by_vpidx(struct kvm *kvm, u32 vpidx)
131 {
132         struct kvm_vcpu *vcpu = NULL;
133         int i;
134
135         if (vpidx < KVM_MAX_VCPUS)
136                 vcpu = kvm_get_vcpu(kvm, vpidx);
137         if (vcpu && vcpu_to_hv_vcpu(vcpu)->vp_index == vpidx)
138                 return vcpu;
139         kvm_for_each_vcpu(i, vcpu, kvm)
140                 if (vcpu_to_hv_vcpu(vcpu)->vp_index == vpidx)
141                         return vcpu;
142         return NULL;
143 }
144
145 static struct kvm_vcpu_hv_synic *synic_get(struct kvm *kvm, u32 vpidx)
146 {
147         struct kvm_vcpu *vcpu;
148         struct kvm_vcpu_hv_synic *synic;
149
150         vcpu = get_vcpu_by_vpidx(kvm, vpidx);
151         if (!vcpu)
152                 return NULL;
153         synic = vcpu_to_synic(vcpu);
154         return (synic->active) ? synic : NULL;
155 }
156
157 static void synic_clear_sint_msg_pending(struct kvm_vcpu_hv_synic *synic,
158                                         u32 sint)
159 {
160         struct kvm_vcpu *vcpu = synic_to_vcpu(synic);
161         struct page *page;
162         gpa_t gpa;
163         struct hv_message *msg;
164         struct hv_message_page *msg_page;
165
166         gpa = synic->msg_page & PAGE_MASK;
167         page = kvm_vcpu_gfn_to_page(vcpu, gpa >> PAGE_SHIFT);
168         if (is_error_page(page)) {
169                 vcpu_err(vcpu, "Hyper-V SynIC can't get msg page, gpa 0x%llx\n",
170                          gpa);
171                 return;
172         }
173         msg_page = kmap_atomic(page);
174
175         msg = &msg_page->sint_message[sint];
176         msg->header.message_flags.msg_pending = 0;
177
178         kunmap_atomic(msg_page);
179         kvm_release_page_dirty(page);
180         kvm_vcpu_mark_page_dirty(vcpu, gpa >> PAGE_SHIFT);
181 }
182
183 static void kvm_hv_notify_acked_sint(struct kvm_vcpu *vcpu, u32 sint)
184 {
185         struct kvm *kvm = vcpu->kvm;
186         struct kvm_vcpu_hv_synic *synic = vcpu_to_synic(vcpu);
187         struct kvm_vcpu_hv *hv_vcpu = vcpu_to_hv_vcpu(vcpu);
188         struct kvm_vcpu_hv_stimer *stimer;
189         int gsi, idx, stimers_pending;
190
191         trace_kvm_hv_notify_acked_sint(vcpu->vcpu_id, sint);
192
193         if (synic->msg_page & HV_SYNIC_SIMP_ENABLE)
194                 synic_clear_sint_msg_pending(synic, sint);
195
196         /* Try to deliver pending Hyper-V SynIC timers messages */
197         stimers_pending = 0;
198         for (idx = 0; idx < ARRAY_SIZE(hv_vcpu->stimer); idx++) {
199                 stimer = &hv_vcpu->stimer[idx];
200                 if (stimer->msg_pending &&
201                     (stimer->config & HV_STIMER_ENABLE) &&
202                     HV_STIMER_SINT(stimer->config) == sint) {
203                         set_bit(stimer->index,
204                                 hv_vcpu->stimer_pending_bitmap);
205                         stimers_pending++;
206                 }
207         }
208         if (stimers_pending)
209                 kvm_make_request(KVM_REQ_HV_STIMER, vcpu);
210
211         idx = srcu_read_lock(&kvm->irq_srcu);
212         gsi = atomic_read(&synic->sint_to_gsi[sint]);
213         if (gsi != -1)
214                 kvm_notify_acked_gsi(kvm, gsi);
215         srcu_read_unlock(&kvm->irq_srcu, idx);
216 }
217
218 static void synic_exit(struct kvm_vcpu_hv_synic *synic, u32 msr)
219 {
220         struct kvm_vcpu *vcpu = synic_to_vcpu(synic);
221         struct kvm_vcpu_hv *hv_vcpu = &vcpu->arch.hyperv;
222
223         hv_vcpu->exit.type = KVM_EXIT_HYPERV_SYNIC;
224         hv_vcpu->exit.u.synic.msr = msr;
225         hv_vcpu->exit.u.synic.control = synic->control;
226         hv_vcpu->exit.u.synic.evt_page = synic->evt_page;
227         hv_vcpu->exit.u.synic.msg_page = synic->msg_page;
228
229         kvm_make_request(KVM_REQ_HV_EXIT, vcpu);
230 }
231
232 static int synic_set_msr(struct kvm_vcpu_hv_synic *synic,
233                          u32 msr, u64 data, bool host)
234 {
235         struct kvm_vcpu *vcpu = synic_to_vcpu(synic);
236         int ret;
237
238         if (!synic->active)
239                 return 1;
240
241         trace_kvm_hv_synic_set_msr(vcpu->vcpu_id, msr, data, host);
242
243         ret = 0;
244         switch (msr) {
245         case HV_X64_MSR_SCONTROL:
246                 synic->control = data;
247                 if (!host)
248                         synic_exit(synic, msr);
249                 break;
250         case HV_X64_MSR_SVERSION:
251                 if (!host) {
252                         ret = 1;
253                         break;
254                 }
255                 synic->version = data;
256                 break;
257         case HV_X64_MSR_SIEFP:
258                 if ((data & HV_SYNIC_SIEFP_ENABLE) && !host &&
259                     !synic->dont_zero_synic_pages)
260                         if (kvm_clear_guest(vcpu->kvm,
261                                             data & PAGE_MASK, PAGE_SIZE)) {
262                                 ret = 1;
263                                 break;
264                         }
265                 synic->evt_page = data;
266                 if (!host)
267                         synic_exit(synic, msr);
268                 break;
269         case HV_X64_MSR_SIMP:
270                 if ((data & HV_SYNIC_SIMP_ENABLE) && !host &&
271                     !synic->dont_zero_synic_pages)
272                         if (kvm_clear_guest(vcpu->kvm,
273                                             data & PAGE_MASK, PAGE_SIZE)) {
274                                 ret = 1;
275                                 break;
276                         }
277                 synic->msg_page = data;
278                 if (!host)
279                         synic_exit(synic, msr);
280                 break;
281         case HV_X64_MSR_EOM: {
282                 int i;
283
284                 for (i = 0; i < ARRAY_SIZE(synic->sint); i++)
285                         kvm_hv_notify_acked_sint(vcpu, i);
286                 break;
287         }
288         case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
289                 ret = synic_set_sint(synic, msr - HV_X64_MSR_SINT0, data, host);
290                 break;
291         default:
292                 ret = 1;
293                 break;
294         }
295         return ret;
296 }
297
298 static int synic_get_msr(struct kvm_vcpu_hv_synic *synic, u32 msr, u64 *pdata)
299 {
300         int ret;
301
302         if (!synic->active)
303                 return 1;
304
305         ret = 0;
306         switch (msr) {
307         case HV_X64_MSR_SCONTROL:
308                 *pdata = synic->control;
309                 break;
310         case HV_X64_MSR_SVERSION:
311                 *pdata = synic->version;
312                 break;
313         case HV_X64_MSR_SIEFP:
314                 *pdata = synic->evt_page;
315                 break;
316         case HV_X64_MSR_SIMP:
317                 *pdata = synic->msg_page;
318                 break;
319         case HV_X64_MSR_EOM:
320                 *pdata = 0;
321                 break;
322         case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
323                 *pdata = atomic64_read(&synic->sint[msr - HV_X64_MSR_SINT0]);
324                 break;
325         default:
326                 ret = 1;
327                 break;
328         }
329         return ret;
330 }
331
332 static int synic_set_irq(struct kvm_vcpu_hv_synic *synic, u32 sint)
333 {
334         struct kvm_vcpu *vcpu = synic_to_vcpu(synic);
335         struct kvm_lapic_irq irq;
336         int ret, vector;
337
338         if (sint >= ARRAY_SIZE(synic->sint))
339                 return -EINVAL;
340
341         vector = synic_get_sint_vector(synic_read_sint(synic, sint));
342         if (vector < 0)
343                 return -ENOENT;
344
345         memset(&irq, 0, sizeof(irq));
346         irq.shorthand = APIC_DEST_SELF;
347         irq.dest_mode = APIC_DEST_PHYSICAL;
348         irq.delivery_mode = APIC_DM_FIXED;
349         irq.vector = vector;
350         irq.level = 1;
351
352         ret = kvm_irq_delivery_to_apic(vcpu->kvm, vcpu->arch.apic, &irq, NULL);
353         trace_kvm_hv_synic_set_irq(vcpu->vcpu_id, sint, irq.vector, ret);
354         return ret;
355 }
356
357 int kvm_hv_synic_set_irq(struct kvm *kvm, u32 vpidx, u32 sint)
358 {
359         struct kvm_vcpu_hv_synic *synic;
360
361         synic = synic_get(kvm, vpidx);
362         if (!synic)
363                 return -EINVAL;
364
365         return synic_set_irq(synic, sint);
366 }
367
368 void kvm_hv_synic_send_eoi(struct kvm_vcpu *vcpu, int vector)
369 {
370         struct kvm_vcpu_hv_synic *synic = vcpu_to_synic(vcpu);
371         int i;
372
373         trace_kvm_hv_synic_send_eoi(vcpu->vcpu_id, vector);
374
375         for (i = 0; i < ARRAY_SIZE(synic->sint); i++)
376                 if (synic_get_sint_vector(synic_read_sint(synic, i)) == vector)
377                         kvm_hv_notify_acked_sint(vcpu, i);
378 }
379
380 static int kvm_hv_set_sint_gsi(struct kvm *kvm, u32 vpidx, u32 sint, int gsi)
381 {
382         struct kvm_vcpu_hv_synic *synic;
383
384         synic = synic_get(kvm, vpidx);
385         if (!synic)
386                 return -EINVAL;
387
388         if (sint >= ARRAY_SIZE(synic->sint_to_gsi))
389                 return -EINVAL;
390
391         atomic_set(&synic->sint_to_gsi[sint], gsi);
392         return 0;
393 }
394
395 void kvm_hv_irq_routing_update(struct kvm *kvm)
396 {
397         struct kvm_irq_routing_table *irq_rt;
398         struct kvm_kernel_irq_routing_entry *e;
399         u32 gsi;
400
401         irq_rt = srcu_dereference_check(kvm->irq_routing, &kvm->irq_srcu,
402                                         lockdep_is_held(&kvm->irq_lock));
403
404         for (gsi = 0; gsi < irq_rt->nr_rt_entries; gsi++) {
405                 hlist_for_each_entry(e, &irq_rt->map[gsi], link) {
406                         if (e->type == KVM_IRQ_ROUTING_HV_SINT)
407                                 kvm_hv_set_sint_gsi(kvm, e->hv_sint.vcpu,
408                                                     e->hv_sint.sint, gsi);
409                 }
410         }
411 }
412
413 static void synic_init(struct kvm_vcpu_hv_synic *synic)
414 {
415         int i;
416
417         memset(synic, 0, sizeof(*synic));
418         synic->version = HV_SYNIC_VERSION_1;
419         for (i = 0; i < ARRAY_SIZE(synic->sint); i++) {
420                 atomic64_set(&synic->sint[i], HV_SYNIC_SINT_MASKED);
421                 atomic_set(&synic->sint_to_gsi[i], -1);
422         }
423 }
424
425 static u64 get_time_ref_counter(struct kvm *kvm)
426 {
427         struct kvm_hv *hv = &kvm->arch.hyperv;
428         struct kvm_vcpu *vcpu;
429         u64 tsc;
430
431         /*
432          * The guest has not set up the TSC page or the clock isn't
433          * stable, fall back to get_kvmclock_ns.
434          */
435         if (!hv->tsc_ref.tsc_sequence)
436                 return div_u64(get_kvmclock_ns(kvm), 100);
437
438         vcpu = kvm_get_vcpu(kvm, 0);
439         tsc = kvm_read_l1_tsc(vcpu, rdtsc());
440         return mul_u64_u64_shr(tsc, hv->tsc_ref.tsc_scale, 64)
441                 + hv->tsc_ref.tsc_offset;
442 }
443
444 static void stimer_mark_pending(struct kvm_vcpu_hv_stimer *stimer,
445                                 bool vcpu_kick)
446 {
447         struct kvm_vcpu *vcpu = stimer_to_vcpu(stimer);
448
449         set_bit(stimer->index,
450                 vcpu_to_hv_vcpu(vcpu)->stimer_pending_bitmap);
451         kvm_make_request(KVM_REQ_HV_STIMER, vcpu);
452         if (vcpu_kick)
453                 kvm_vcpu_kick(vcpu);
454 }
455
456 static void stimer_cleanup(struct kvm_vcpu_hv_stimer *stimer)
457 {
458         struct kvm_vcpu *vcpu = stimer_to_vcpu(stimer);
459
460         trace_kvm_hv_stimer_cleanup(stimer_to_vcpu(stimer)->vcpu_id,
461                                     stimer->index);
462
463         hrtimer_cancel(&stimer->timer);
464         clear_bit(stimer->index,
465                   vcpu_to_hv_vcpu(vcpu)->stimer_pending_bitmap);
466         stimer->msg_pending = false;
467         stimer->exp_time = 0;
468 }
469
470 static enum hrtimer_restart stimer_timer_callback(struct hrtimer *timer)
471 {
472         struct kvm_vcpu_hv_stimer *stimer;
473
474         stimer = container_of(timer, struct kvm_vcpu_hv_stimer, timer);
475         trace_kvm_hv_stimer_callback(stimer_to_vcpu(stimer)->vcpu_id,
476                                      stimer->index);
477         stimer_mark_pending(stimer, true);
478
479         return HRTIMER_NORESTART;
480 }
481
482 /*
483  * stimer_start() assumptions:
484  * a) stimer->count is not equal to 0
485  * b) stimer->config has HV_STIMER_ENABLE flag
486  */
487 static int stimer_start(struct kvm_vcpu_hv_stimer *stimer)
488 {
489         u64 time_now;
490         ktime_t ktime_now;
491
492         time_now = get_time_ref_counter(stimer_to_vcpu(stimer)->kvm);
493         ktime_now = ktime_get();
494
495         if (stimer->config & HV_STIMER_PERIODIC) {
496                 if (stimer->exp_time) {
497                         if (time_now >= stimer->exp_time) {
498                                 u64 remainder;
499
500                                 div64_u64_rem(time_now - stimer->exp_time,
501                                               stimer->count, &remainder);
502                                 stimer->exp_time =
503                                         time_now + (stimer->count - remainder);
504                         }
505                 } else
506                         stimer->exp_time = time_now + stimer->count;
507
508                 trace_kvm_hv_stimer_start_periodic(
509                                         stimer_to_vcpu(stimer)->vcpu_id,
510                                         stimer->index,
511                                         time_now, stimer->exp_time);
512
513                 hrtimer_start(&stimer->timer,
514                               ktime_add_ns(ktime_now,
515                                            100 * (stimer->exp_time - time_now)),
516                               HRTIMER_MODE_ABS);
517                 return 0;
518         }
519         stimer->exp_time = stimer->count;
520         if (time_now >= stimer->count) {
521                 /*
522                  * Expire timer according to Hypervisor Top-Level Functional
523                  * specification v4(15.3.1):
524                  * "If a one shot is enabled and the specified count is in
525                  * the past, it will expire immediately."
526                  */
527                 stimer_mark_pending(stimer, false);
528                 return 0;
529         }
530
531         trace_kvm_hv_stimer_start_one_shot(stimer_to_vcpu(stimer)->vcpu_id,
532                                            stimer->index,
533                                            time_now, stimer->count);
534
535         hrtimer_start(&stimer->timer,
536                       ktime_add_ns(ktime_now, 100 * (stimer->count - time_now)),
537                       HRTIMER_MODE_ABS);
538         return 0;
539 }
540
541 static int stimer_set_config(struct kvm_vcpu_hv_stimer *stimer, u64 config,
542                              bool host)
543 {
544         trace_kvm_hv_stimer_set_config(stimer_to_vcpu(stimer)->vcpu_id,
545                                        stimer->index, config, host);
546
547         stimer_cleanup(stimer);
548         if ((stimer->config & HV_STIMER_ENABLE) && HV_STIMER_SINT(config) == 0)
549                 config &= ~HV_STIMER_ENABLE;
550         stimer->config = config;
551         stimer_mark_pending(stimer, false);
552         return 0;
553 }
554
555 static int stimer_set_count(struct kvm_vcpu_hv_stimer *stimer, u64 count,
556                             bool host)
557 {
558         trace_kvm_hv_stimer_set_count(stimer_to_vcpu(stimer)->vcpu_id,
559                                       stimer->index, count, host);
560
561         stimer_cleanup(stimer);
562         stimer->count = count;
563         if (stimer->count == 0)
564                 stimer->config &= ~HV_STIMER_ENABLE;
565         else if (stimer->config & HV_STIMER_AUTOENABLE)
566                 stimer->config |= HV_STIMER_ENABLE;
567         stimer_mark_pending(stimer, false);
568         return 0;
569 }
570
571 static int stimer_get_config(struct kvm_vcpu_hv_stimer *stimer, u64 *pconfig)
572 {
573         *pconfig = stimer->config;
574         return 0;
575 }
576
577 static int stimer_get_count(struct kvm_vcpu_hv_stimer *stimer, u64 *pcount)
578 {
579         *pcount = stimer->count;
580         return 0;
581 }
582
583 static int synic_deliver_msg(struct kvm_vcpu_hv_synic *synic, u32 sint,
584                              struct hv_message *src_msg)
585 {
586         struct kvm_vcpu *vcpu = synic_to_vcpu(synic);
587         struct page *page;
588         gpa_t gpa;
589         struct hv_message *dst_msg;
590         int r;
591         struct hv_message_page *msg_page;
592
593         if (!(synic->msg_page & HV_SYNIC_SIMP_ENABLE))
594                 return -ENOENT;
595
596         gpa = synic->msg_page & PAGE_MASK;
597         page = kvm_vcpu_gfn_to_page(vcpu, gpa >> PAGE_SHIFT);
598         if (is_error_page(page))
599                 return -EFAULT;
600
601         msg_page = kmap_atomic(page);
602         dst_msg = &msg_page->sint_message[sint];
603         if (sync_cmpxchg(&dst_msg->header.message_type, HVMSG_NONE,
604                          src_msg->header.message_type) != HVMSG_NONE) {
605                 dst_msg->header.message_flags.msg_pending = 1;
606                 r = -EAGAIN;
607         } else {
608                 memcpy(&dst_msg->u.payload, &src_msg->u.payload,
609                        src_msg->header.payload_size);
610                 dst_msg->header.message_type = src_msg->header.message_type;
611                 dst_msg->header.payload_size = src_msg->header.payload_size;
612                 r = synic_set_irq(synic, sint);
613                 if (r >= 1)
614                         r = 0;
615                 else if (r == 0)
616                         r = -EFAULT;
617         }
618         kunmap_atomic(msg_page);
619         kvm_release_page_dirty(page);
620         kvm_vcpu_mark_page_dirty(vcpu, gpa >> PAGE_SHIFT);
621         return r;
622 }
623
624 static int stimer_send_msg(struct kvm_vcpu_hv_stimer *stimer)
625 {
626         struct kvm_vcpu *vcpu = stimer_to_vcpu(stimer);
627         struct hv_message *msg = &stimer->msg;
628         struct hv_timer_message_payload *payload =
629                         (struct hv_timer_message_payload *)&msg->u.payload;
630
631         payload->expiration_time = stimer->exp_time;
632         payload->delivery_time = get_time_ref_counter(vcpu->kvm);
633         return synic_deliver_msg(vcpu_to_synic(vcpu),
634                                  HV_STIMER_SINT(stimer->config), msg);
635 }
636
637 static void stimer_expiration(struct kvm_vcpu_hv_stimer *stimer)
638 {
639         int r;
640
641         stimer->msg_pending = true;
642         r = stimer_send_msg(stimer);
643         trace_kvm_hv_stimer_expiration(stimer_to_vcpu(stimer)->vcpu_id,
644                                        stimer->index, r);
645         if (!r) {
646                 stimer->msg_pending = false;
647                 if (!(stimer->config & HV_STIMER_PERIODIC))
648                         stimer->config &= ~HV_STIMER_ENABLE;
649         }
650 }
651
652 void kvm_hv_process_stimers(struct kvm_vcpu *vcpu)
653 {
654         struct kvm_vcpu_hv *hv_vcpu = vcpu_to_hv_vcpu(vcpu);
655         struct kvm_vcpu_hv_stimer *stimer;
656         u64 time_now, exp_time;
657         int i;
658
659         for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++)
660                 if (test_and_clear_bit(i, hv_vcpu->stimer_pending_bitmap)) {
661                         stimer = &hv_vcpu->stimer[i];
662                         if (stimer->config & HV_STIMER_ENABLE) {
663                                 exp_time = stimer->exp_time;
664
665                                 if (exp_time) {
666                                         time_now =
667                                                 get_time_ref_counter(vcpu->kvm);
668                                         if (time_now >= exp_time)
669                                                 stimer_expiration(stimer);
670                                 }
671
672                                 if ((stimer->config & HV_STIMER_ENABLE) &&
673                                     stimer->count) {
674                                         if (!stimer->msg_pending)
675                                                 stimer_start(stimer);
676                                 } else
677                                         stimer_cleanup(stimer);
678                         }
679                 }
680 }
681
682 void kvm_hv_vcpu_uninit(struct kvm_vcpu *vcpu)
683 {
684         struct kvm_vcpu_hv *hv_vcpu = vcpu_to_hv_vcpu(vcpu);
685         int i;
686
687         for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++)
688                 stimer_cleanup(&hv_vcpu->stimer[i]);
689 }
690
691 static void stimer_prepare_msg(struct kvm_vcpu_hv_stimer *stimer)
692 {
693         struct hv_message *msg = &stimer->msg;
694         struct hv_timer_message_payload *payload =
695                         (struct hv_timer_message_payload *)&msg->u.payload;
696
697         memset(&msg->header, 0, sizeof(msg->header));
698         msg->header.message_type = HVMSG_TIMER_EXPIRED;
699         msg->header.payload_size = sizeof(*payload);
700
701         payload->timer_index = stimer->index;
702         payload->expiration_time = 0;
703         payload->delivery_time = 0;
704 }
705
706 static void stimer_init(struct kvm_vcpu_hv_stimer *stimer, int timer_index)
707 {
708         memset(stimer, 0, sizeof(*stimer));
709         stimer->index = timer_index;
710         hrtimer_init(&stimer->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
711         stimer->timer.function = stimer_timer_callback;
712         stimer_prepare_msg(stimer);
713 }
714
715 void kvm_hv_vcpu_init(struct kvm_vcpu *vcpu)
716 {
717         struct kvm_vcpu_hv *hv_vcpu = vcpu_to_hv_vcpu(vcpu);
718         int i;
719
720         synic_init(&hv_vcpu->synic);
721
722         bitmap_zero(hv_vcpu->stimer_pending_bitmap, HV_SYNIC_STIMER_COUNT);
723         for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++)
724                 stimer_init(&hv_vcpu->stimer[i], i);
725 }
726
727 void kvm_hv_vcpu_postcreate(struct kvm_vcpu *vcpu)
728 {
729         struct kvm_vcpu_hv *hv_vcpu = vcpu_to_hv_vcpu(vcpu);
730
731         hv_vcpu->vp_index = kvm_vcpu_get_idx(vcpu);
732 }
733
734 int kvm_hv_activate_synic(struct kvm_vcpu *vcpu, bool dont_zero_synic_pages)
735 {
736         struct kvm_vcpu_hv_synic *synic = vcpu_to_synic(vcpu);
737
738         /*
739          * Hyper-V SynIC auto EOI SINT's are
740          * not compatible with APICV, so deactivate APICV
741          */
742         kvm_vcpu_deactivate_apicv(vcpu);
743         synic->active = true;
744         synic->dont_zero_synic_pages = dont_zero_synic_pages;
745         return 0;
746 }
747
748 static bool kvm_hv_msr_partition_wide(u32 msr)
749 {
750         bool r = false;
751
752         switch (msr) {
753         case HV_X64_MSR_GUEST_OS_ID:
754         case HV_X64_MSR_HYPERCALL:
755         case HV_X64_MSR_REFERENCE_TSC:
756         case HV_X64_MSR_TIME_REF_COUNT:
757         case HV_X64_MSR_CRASH_CTL:
758         case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
759         case HV_X64_MSR_RESET:
760         case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
761         case HV_X64_MSR_TSC_EMULATION_CONTROL:
762         case HV_X64_MSR_TSC_EMULATION_STATUS:
763                 r = true;
764                 break;
765         }
766
767         return r;
768 }
769
770 static int kvm_hv_msr_get_crash_data(struct kvm_vcpu *vcpu,
771                                      u32 index, u64 *pdata)
772 {
773         struct kvm_hv *hv = &vcpu->kvm->arch.hyperv;
774
775         if (WARN_ON_ONCE(index >= ARRAY_SIZE(hv->hv_crash_param)))
776                 return -EINVAL;
777
778         *pdata = hv->hv_crash_param[index];
779         return 0;
780 }
781
782 static int kvm_hv_msr_get_crash_ctl(struct kvm_vcpu *vcpu, u64 *pdata)
783 {
784         struct kvm_hv *hv = &vcpu->kvm->arch.hyperv;
785
786         *pdata = hv->hv_crash_ctl;
787         return 0;
788 }
789
790 static int kvm_hv_msr_set_crash_ctl(struct kvm_vcpu *vcpu, u64 data, bool host)
791 {
792         struct kvm_hv *hv = &vcpu->kvm->arch.hyperv;
793
794         if (host)
795                 hv->hv_crash_ctl = data & HV_X64_MSR_CRASH_CTL_NOTIFY;
796
797         if (!host && (data & HV_X64_MSR_CRASH_CTL_NOTIFY)) {
798
799                 vcpu_debug(vcpu, "hv crash (0x%llx 0x%llx 0x%llx 0x%llx 0x%llx)\n",
800                           hv->hv_crash_param[0],
801                           hv->hv_crash_param[1],
802                           hv->hv_crash_param[2],
803                           hv->hv_crash_param[3],
804                           hv->hv_crash_param[4]);
805
806                 /* Send notification about crash to user space */
807                 kvm_make_request(KVM_REQ_HV_CRASH, vcpu);
808         }
809
810         return 0;
811 }
812
813 static int kvm_hv_msr_set_crash_data(struct kvm_vcpu *vcpu,
814                                      u32 index, u64 data)
815 {
816         struct kvm_hv *hv = &vcpu->kvm->arch.hyperv;
817
818         if (WARN_ON_ONCE(index >= ARRAY_SIZE(hv->hv_crash_param)))
819                 return -EINVAL;
820
821         hv->hv_crash_param[index] = data;
822         return 0;
823 }
824
825 /*
826  * The kvmclock and Hyper-V TSC page use similar formulas, and converting
827  * between them is possible:
828  *
829  * kvmclock formula:
830  *    nsec = (ticks - tsc_timestamp) * tsc_to_system_mul * 2^(tsc_shift-32)
831  *           + system_time
832  *
833  * Hyper-V formula:
834  *    nsec/100 = ticks * scale / 2^64 + offset
835  *
836  * When tsc_timestamp = system_time = 0, offset is zero in the Hyper-V formula.
837  * By dividing the kvmclock formula by 100 and equating what's left we get:
838  *    ticks * scale / 2^64 = ticks * tsc_to_system_mul * 2^(tsc_shift-32) / 100
839  *            scale / 2^64 =         tsc_to_system_mul * 2^(tsc_shift-32) / 100
840  *            scale        =         tsc_to_system_mul * 2^(32+tsc_shift) / 100
841  *
842  * Now expand the kvmclock formula and divide by 100:
843  *    nsec = ticks * tsc_to_system_mul * 2^(tsc_shift-32)
844  *           - tsc_timestamp * tsc_to_system_mul * 2^(tsc_shift-32)
845  *           + system_time
846  *    nsec/100 = ticks * tsc_to_system_mul * 2^(tsc_shift-32) / 100
847  *               - tsc_timestamp * tsc_to_system_mul * 2^(tsc_shift-32) / 100
848  *               + system_time / 100
849  *
850  * Replace tsc_to_system_mul * 2^(tsc_shift-32) / 100 by scale / 2^64:
851  *    nsec/100 = ticks * scale / 2^64
852  *               - tsc_timestamp * scale / 2^64
853  *               + system_time / 100
854  *
855  * Equate with the Hyper-V formula so that ticks * scale / 2^64 cancels out:
856  *    offset = system_time / 100 - tsc_timestamp * scale / 2^64
857  *
858  * These two equivalencies are implemented in this function.
859  */
860 static bool compute_tsc_page_parameters(struct pvclock_vcpu_time_info *hv_clock,
861                                         HV_REFERENCE_TSC_PAGE *tsc_ref)
862 {
863         u64 max_mul;
864
865         if (!(hv_clock->flags & PVCLOCK_TSC_STABLE_BIT))
866                 return false;
867
868         /*
869          * check if scale would overflow, if so we use the time ref counter
870          *    tsc_to_system_mul * 2^(tsc_shift+32) / 100 >= 2^64
871          *    tsc_to_system_mul / 100 >= 2^(32-tsc_shift)
872          *    tsc_to_system_mul >= 100 * 2^(32-tsc_shift)
873          */
874         max_mul = 100ull << (32 - hv_clock->tsc_shift);
875         if (hv_clock->tsc_to_system_mul >= max_mul)
876                 return false;
877
878         /*
879          * Otherwise compute the scale and offset according to the formulas
880          * derived above.
881          */
882         tsc_ref->tsc_scale =
883                 mul_u64_u32_div(1ULL << (32 + hv_clock->tsc_shift),
884                                 hv_clock->tsc_to_system_mul,
885                                 100);
886
887         tsc_ref->tsc_offset = hv_clock->system_time;
888         do_div(tsc_ref->tsc_offset, 100);
889         tsc_ref->tsc_offset -=
890                 mul_u64_u64_shr(hv_clock->tsc_timestamp, tsc_ref->tsc_scale, 64);
891         return true;
892 }
893
894 void kvm_hv_setup_tsc_page(struct kvm *kvm,
895                            struct pvclock_vcpu_time_info *hv_clock)
896 {
897         struct kvm_hv *hv = &kvm->arch.hyperv;
898         u32 tsc_seq;
899         u64 gfn;
900
901         BUILD_BUG_ON(sizeof(tsc_seq) != sizeof(hv->tsc_ref.tsc_sequence));
902         BUILD_BUG_ON(offsetof(HV_REFERENCE_TSC_PAGE, tsc_sequence) != 0);
903
904         if (!(hv->hv_tsc_page & HV_X64_MSR_TSC_REFERENCE_ENABLE))
905                 return;
906
907         mutex_lock(&kvm->arch.hyperv.hv_lock);
908         if (!(hv->hv_tsc_page & HV_X64_MSR_TSC_REFERENCE_ENABLE))
909                 goto out_unlock;
910
911         gfn = hv->hv_tsc_page >> HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT;
912         /*
913          * Because the TSC parameters only vary when there is a
914          * change in the master clock, do not bother with caching.
915          */
916         if (unlikely(kvm_read_guest(kvm, gfn_to_gpa(gfn),
917                                     &tsc_seq, sizeof(tsc_seq))))
918                 goto out_unlock;
919
920         /*
921          * While we're computing and writing the parameters, force the
922          * guest to use the time reference count MSR.
923          */
924         hv->tsc_ref.tsc_sequence = 0;
925         if (kvm_write_guest(kvm, gfn_to_gpa(gfn),
926                             &hv->tsc_ref, sizeof(hv->tsc_ref.tsc_sequence)))
927                 goto out_unlock;
928
929         if (!compute_tsc_page_parameters(hv_clock, &hv->tsc_ref))
930                 goto out_unlock;
931
932         /* Ensure sequence is zero before writing the rest of the struct.  */
933         smp_wmb();
934         if (kvm_write_guest(kvm, gfn_to_gpa(gfn), &hv->tsc_ref, sizeof(hv->tsc_ref)))
935                 goto out_unlock;
936
937         /*
938          * Now switch to the TSC page mechanism by writing the sequence.
939          */
940         tsc_seq++;
941         if (tsc_seq == 0xFFFFFFFF || tsc_seq == 0)
942                 tsc_seq = 1;
943
944         /* Write the struct entirely before the non-zero sequence.  */
945         smp_wmb();
946
947         hv->tsc_ref.tsc_sequence = tsc_seq;
948         kvm_write_guest(kvm, gfn_to_gpa(gfn),
949                         &hv->tsc_ref, sizeof(hv->tsc_ref.tsc_sequence));
950 out_unlock:
951         mutex_unlock(&kvm->arch.hyperv.hv_lock);
952 }
953
954 static int kvm_hv_set_msr_pw(struct kvm_vcpu *vcpu, u32 msr, u64 data,
955                              bool host)
956 {
957         struct kvm *kvm = vcpu->kvm;
958         struct kvm_hv *hv = &kvm->arch.hyperv;
959
960         switch (msr) {
961         case HV_X64_MSR_GUEST_OS_ID:
962                 hv->hv_guest_os_id = data;
963                 /* setting guest os id to zero disables hypercall page */
964                 if (!hv->hv_guest_os_id)
965                         hv->hv_hypercall &= ~HV_X64_MSR_HYPERCALL_ENABLE;
966                 break;
967         case HV_X64_MSR_HYPERCALL: {
968                 u64 gfn;
969                 unsigned long addr;
970                 u8 instructions[4];
971
972                 /* if guest os id is not set hypercall should remain disabled */
973                 if (!hv->hv_guest_os_id)
974                         break;
975                 if (!(data & HV_X64_MSR_HYPERCALL_ENABLE)) {
976                         hv->hv_hypercall = data;
977                         break;
978                 }
979                 gfn = data >> HV_X64_MSR_HYPERCALL_PAGE_ADDRESS_SHIFT;
980                 addr = gfn_to_hva(kvm, gfn);
981                 if (kvm_is_error_hva(addr))
982                         return 1;
983                 kvm_x86_ops->patch_hypercall(vcpu, instructions);
984                 ((unsigned char *)instructions)[3] = 0xc3; /* ret */
985                 if (__copy_to_user((void __user *)addr, instructions, 4))
986                         return 1;
987                 hv->hv_hypercall = data;
988                 mark_page_dirty(kvm, gfn);
989                 break;
990         }
991         case HV_X64_MSR_REFERENCE_TSC:
992                 hv->hv_tsc_page = data;
993                 if (hv->hv_tsc_page & HV_X64_MSR_TSC_REFERENCE_ENABLE)
994                         kvm_make_request(KVM_REQ_MASTERCLOCK_UPDATE, vcpu);
995                 break;
996         case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
997                 return kvm_hv_msr_set_crash_data(vcpu,
998                                                  msr - HV_X64_MSR_CRASH_P0,
999                                                  data);
1000         case HV_X64_MSR_CRASH_CTL:
1001                 return kvm_hv_msr_set_crash_ctl(vcpu, data, host);
1002         case HV_X64_MSR_RESET:
1003                 if (data == 1) {
1004                         vcpu_debug(vcpu, "hyper-v reset requested\n");
1005                         kvm_make_request(KVM_REQ_HV_RESET, vcpu);
1006                 }
1007                 break;
1008         case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
1009                 hv->hv_reenlightenment_control = data;
1010                 break;
1011         case HV_X64_MSR_TSC_EMULATION_CONTROL:
1012                 hv->hv_tsc_emulation_control = data;
1013                 break;
1014         case HV_X64_MSR_TSC_EMULATION_STATUS:
1015                 hv->hv_tsc_emulation_status = data;
1016                 break;
1017         default:
1018                 vcpu_unimpl(vcpu, "Hyper-V uhandled wrmsr: 0x%x data 0x%llx\n",
1019                             msr, data);
1020                 return 1;
1021         }
1022         return 0;
1023 }
1024
1025 /* Calculate cpu time spent by current task in 100ns units */
1026 static u64 current_task_runtime_100ns(void)
1027 {
1028         u64 utime, stime;
1029
1030         task_cputime_adjusted(current, &utime, &stime);
1031
1032         return div_u64(utime + stime, 100);
1033 }
1034
1035 static int kvm_hv_set_msr(struct kvm_vcpu *vcpu, u32 msr, u64 data, bool host)
1036 {
1037         struct kvm_vcpu_hv *hv = &vcpu->arch.hyperv;
1038
1039         switch (msr) {
1040         case HV_X64_MSR_VP_INDEX:
1041                 if (!host)
1042                         return 1;
1043                 hv->vp_index = (u32)data;
1044                 break;
1045         case HV_X64_MSR_VP_ASSIST_PAGE: {
1046                 u64 gfn;
1047                 unsigned long addr;
1048
1049                 if (!(data & HV_X64_MSR_VP_ASSIST_PAGE_ENABLE)) {
1050                         hv->hv_vapic = data;
1051                         if (kvm_lapic_enable_pv_eoi(vcpu, 0))
1052                                 return 1;
1053                         break;
1054                 }
1055                 gfn = data >> HV_X64_MSR_VP_ASSIST_PAGE_ADDRESS_SHIFT;
1056                 addr = kvm_vcpu_gfn_to_hva(vcpu, gfn);
1057                 if (kvm_is_error_hva(addr))
1058                         return 1;
1059                 if (__clear_user((void __user *)addr, PAGE_SIZE))
1060                         return 1;
1061                 hv->hv_vapic = data;
1062                 kvm_vcpu_mark_page_dirty(vcpu, gfn);
1063                 if (kvm_lapic_enable_pv_eoi(vcpu,
1064                                             gfn_to_gpa(gfn) | KVM_MSR_ENABLED))
1065                         return 1;
1066                 break;
1067         }
1068         case HV_X64_MSR_EOI:
1069                 return kvm_hv_vapic_msr_write(vcpu, APIC_EOI, data);
1070         case HV_X64_MSR_ICR:
1071                 return kvm_hv_vapic_msr_write(vcpu, APIC_ICR, data);
1072         case HV_X64_MSR_TPR:
1073                 return kvm_hv_vapic_msr_write(vcpu, APIC_TASKPRI, data);
1074         case HV_X64_MSR_VP_RUNTIME:
1075                 if (!host)
1076                         return 1;
1077                 hv->runtime_offset = data - current_task_runtime_100ns();
1078                 break;
1079         case HV_X64_MSR_SCONTROL:
1080         case HV_X64_MSR_SVERSION:
1081         case HV_X64_MSR_SIEFP:
1082         case HV_X64_MSR_SIMP:
1083         case HV_X64_MSR_EOM:
1084         case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
1085                 return synic_set_msr(vcpu_to_synic(vcpu), msr, data, host);
1086         case HV_X64_MSR_STIMER0_CONFIG:
1087         case HV_X64_MSR_STIMER1_CONFIG:
1088         case HV_X64_MSR_STIMER2_CONFIG:
1089         case HV_X64_MSR_STIMER3_CONFIG: {
1090                 int timer_index = (msr - HV_X64_MSR_STIMER0_CONFIG)/2;
1091
1092                 return stimer_set_config(vcpu_to_stimer(vcpu, timer_index),
1093                                          data, host);
1094         }
1095         case HV_X64_MSR_STIMER0_COUNT:
1096         case HV_X64_MSR_STIMER1_COUNT:
1097         case HV_X64_MSR_STIMER2_COUNT:
1098         case HV_X64_MSR_STIMER3_COUNT: {
1099                 int timer_index = (msr - HV_X64_MSR_STIMER0_COUNT)/2;
1100
1101                 return stimer_set_count(vcpu_to_stimer(vcpu, timer_index),
1102                                         data, host);
1103         }
1104         default:
1105                 vcpu_unimpl(vcpu, "Hyper-V uhandled wrmsr: 0x%x data 0x%llx\n",
1106                             msr, data);
1107                 return 1;
1108         }
1109
1110         return 0;
1111 }
1112
1113 static int kvm_hv_get_msr_pw(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata)
1114 {
1115         u64 data = 0;
1116         struct kvm *kvm = vcpu->kvm;
1117         struct kvm_hv *hv = &kvm->arch.hyperv;
1118
1119         switch (msr) {
1120         case HV_X64_MSR_GUEST_OS_ID:
1121                 data = hv->hv_guest_os_id;
1122                 break;
1123         case HV_X64_MSR_HYPERCALL:
1124                 data = hv->hv_hypercall;
1125                 break;
1126         case HV_X64_MSR_TIME_REF_COUNT:
1127                 data = get_time_ref_counter(kvm);
1128                 break;
1129         case HV_X64_MSR_REFERENCE_TSC:
1130                 data = hv->hv_tsc_page;
1131                 break;
1132         case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
1133                 return kvm_hv_msr_get_crash_data(vcpu,
1134                                                  msr - HV_X64_MSR_CRASH_P0,
1135                                                  pdata);
1136         case HV_X64_MSR_CRASH_CTL:
1137                 return kvm_hv_msr_get_crash_ctl(vcpu, pdata);
1138         case HV_X64_MSR_RESET:
1139                 data = 0;
1140                 break;
1141         case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
1142                 data = hv->hv_reenlightenment_control;
1143                 break;
1144         case HV_X64_MSR_TSC_EMULATION_CONTROL:
1145                 data = hv->hv_tsc_emulation_control;
1146                 break;
1147         case HV_X64_MSR_TSC_EMULATION_STATUS:
1148                 data = hv->hv_tsc_emulation_status;
1149                 break;
1150         default:
1151                 vcpu_unimpl(vcpu, "Hyper-V unhandled rdmsr: 0x%x\n", msr);
1152                 return 1;
1153         }
1154
1155         *pdata = data;
1156         return 0;
1157 }
1158
1159 static int kvm_hv_get_msr(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata)
1160 {
1161         u64 data = 0;
1162         struct kvm_vcpu_hv *hv = &vcpu->arch.hyperv;
1163
1164         switch (msr) {
1165         case HV_X64_MSR_VP_INDEX:
1166                 data = hv->vp_index;
1167                 break;
1168         case HV_X64_MSR_EOI:
1169                 return kvm_hv_vapic_msr_read(vcpu, APIC_EOI, pdata);
1170         case HV_X64_MSR_ICR:
1171                 return kvm_hv_vapic_msr_read(vcpu, APIC_ICR, pdata);
1172         case HV_X64_MSR_TPR:
1173                 return kvm_hv_vapic_msr_read(vcpu, APIC_TASKPRI, pdata);
1174         case HV_X64_MSR_VP_ASSIST_PAGE:
1175                 data = hv->hv_vapic;
1176                 break;
1177         case HV_X64_MSR_VP_RUNTIME:
1178                 data = current_task_runtime_100ns() + hv->runtime_offset;
1179                 break;
1180         case HV_X64_MSR_SCONTROL:
1181         case HV_X64_MSR_SVERSION:
1182         case HV_X64_MSR_SIEFP:
1183         case HV_X64_MSR_SIMP:
1184         case HV_X64_MSR_EOM:
1185         case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
1186                 return synic_get_msr(vcpu_to_synic(vcpu), msr, pdata);
1187         case HV_X64_MSR_STIMER0_CONFIG:
1188         case HV_X64_MSR_STIMER1_CONFIG:
1189         case HV_X64_MSR_STIMER2_CONFIG:
1190         case HV_X64_MSR_STIMER3_CONFIG: {
1191                 int timer_index = (msr - HV_X64_MSR_STIMER0_CONFIG)/2;
1192
1193                 return stimer_get_config(vcpu_to_stimer(vcpu, timer_index),
1194                                          pdata);
1195         }
1196         case HV_X64_MSR_STIMER0_COUNT:
1197         case HV_X64_MSR_STIMER1_COUNT:
1198         case HV_X64_MSR_STIMER2_COUNT:
1199         case HV_X64_MSR_STIMER3_COUNT: {
1200                 int timer_index = (msr - HV_X64_MSR_STIMER0_COUNT)/2;
1201
1202                 return stimer_get_count(vcpu_to_stimer(vcpu, timer_index),
1203                                         pdata);
1204         }
1205         case HV_X64_MSR_TSC_FREQUENCY:
1206                 data = (u64)vcpu->arch.virtual_tsc_khz * 1000;
1207                 break;
1208         case HV_X64_MSR_APIC_FREQUENCY:
1209                 data = APIC_BUS_FREQUENCY;
1210                 break;
1211         default:
1212                 vcpu_unimpl(vcpu, "Hyper-V unhandled rdmsr: 0x%x\n", msr);
1213                 return 1;
1214         }
1215         *pdata = data;
1216         return 0;
1217 }
1218
1219 int kvm_hv_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data, bool host)
1220 {
1221         if (kvm_hv_msr_partition_wide(msr)) {
1222                 int r;
1223
1224                 mutex_lock(&vcpu->kvm->arch.hyperv.hv_lock);
1225                 r = kvm_hv_set_msr_pw(vcpu, msr, data, host);
1226                 mutex_unlock(&vcpu->kvm->arch.hyperv.hv_lock);
1227                 return r;
1228         } else
1229                 return kvm_hv_set_msr(vcpu, msr, data, host);
1230 }
1231
1232 int kvm_hv_get_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata)
1233 {
1234         if (kvm_hv_msr_partition_wide(msr)) {
1235                 int r;
1236
1237                 mutex_lock(&vcpu->kvm->arch.hyperv.hv_lock);
1238                 r = kvm_hv_get_msr_pw(vcpu, msr, pdata);
1239                 mutex_unlock(&vcpu->kvm->arch.hyperv.hv_lock);
1240                 return r;
1241         } else
1242                 return kvm_hv_get_msr(vcpu, msr, pdata);
1243 }
1244
1245 bool kvm_hv_hypercall_enabled(struct kvm *kvm)
1246 {
1247         return READ_ONCE(kvm->arch.hyperv.hv_hypercall) & HV_X64_MSR_HYPERCALL_ENABLE;
1248 }
1249
1250 static void kvm_hv_hypercall_set_result(struct kvm_vcpu *vcpu, u64 result)
1251 {
1252         bool longmode;
1253
1254         longmode = is_64_bit_mode(vcpu);
1255         if (longmode)
1256                 kvm_register_write(vcpu, VCPU_REGS_RAX, result);
1257         else {
1258                 kvm_register_write(vcpu, VCPU_REGS_RDX, result >> 32);
1259                 kvm_register_write(vcpu, VCPU_REGS_RAX, result & 0xffffffff);
1260         }
1261 }
1262
1263 static int kvm_hv_hypercall_complete(struct kvm_vcpu *vcpu, u64 result)
1264 {
1265         kvm_hv_hypercall_set_result(vcpu, result);
1266         ++vcpu->stat.hypercalls;
1267         return kvm_skip_emulated_instruction(vcpu);
1268 }
1269
1270 static int kvm_hv_hypercall_complete_userspace(struct kvm_vcpu *vcpu)
1271 {
1272         return kvm_hv_hypercall_complete(vcpu, vcpu->run->hyperv.u.hcall.result);
1273 }
1274
1275 static u16 kvm_hvcall_signal_event(struct kvm_vcpu *vcpu, bool fast, u64 param)
1276 {
1277         struct eventfd_ctx *eventfd;
1278
1279         if (unlikely(!fast)) {
1280                 int ret;
1281                 gpa_t gpa = param;
1282
1283                 if ((gpa & (__alignof__(param) - 1)) ||
1284                     offset_in_page(gpa) + sizeof(param) > PAGE_SIZE)
1285                         return HV_STATUS_INVALID_ALIGNMENT;
1286
1287                 ret = kvm_vcpu_read_guest(vcpu, gpa, &param, sizeof(param));
1288                 if (ret < 0)
1289                         return HV_STATUS_INVALID_ALIGNMENT;
1290         }
1291
1292         /*
1293          * Per spec, bits 32-47 contain the extra "flag number".  However, we
1294          * have no use for it, and in all known usecases it is zero, so just
1295          * report lookup failure if it isn't.
1296          */
1297         if (param & 0xffff00000000ULL)
1298                 return HV_STATUS_INVALID_PORT_ID;
1299         /* remaining bits are reserved-zero */
1300         if (param & ~KVM_HYPERV_CONN_ID_MASK)
1301                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
1302
1303         /* the eventfd is protected by vcpu->kvm->srcu, but conn_to_evt isn't */
1304         rcu_read_lock();
1305         eventfd = idr_find(&vcpu->kvm->arch.hyperv.conn_to_evt, param);
1306         rcu_read_unlock();
1307         if (!eventfd)
1308                 return HV_STATUS_INVALID_PORT_ID;
1309
1310         eventfd_signal(eventfd, 1);
1311         return HV_STATUS_SUCCESS;
1312 }
1313
1314 int kvm_hv_hypercall(struct kvm_vcpu *vcpu)
1315 {
1316         u64 param, ingpa, outgpa, ret = HV_STATUS_SUCCESS;
1317         uint16_t code, rep_idx, rep_cnt;
1318         bool fast, longmode;
1319
1320         /*
1321          * hypercall generates UD from non zero cpl and real mode
1322          * per HYPER-V spec
1323          */
1324         if (kvm_x86_ops->get_cpl(vcpu) != 0 || !is_protmode(vcpu)) {
1325                 kvm_queue_exception(vcpu, UD_VECTOR);
1326                 return 1;
1327         }
1328
1329         longmode = is_64_bit_mode(vcpu);
1330
1331         if (!longmode) {
1332                 param = ((u64)kvm_register_read(vcpu, VCPU_REGS_RDX) << 32) |
1333                         (kvm_register_read(vcpu, VCPU_REGS_RAX) & 0xffffffff);
1334                 ingpa = ((u64)kvm_register_read(vcpu, VCPU_REGS_RBX) << 32) |
1335                         (kvm_register_read(vcpu, VCPU_REGS_RCX) & 0xffffffff);
1336                 outgpa = ((u64)kvm_register_read(vcpu, VCPU_REGS_RDI) << 32) |
1337                         (kvm_register_read(vcpu, VCPU_REGS_RSI) & 0xffffffff);
1338         }
1339 #ifdef CONFIG_X86_64
1340         else {
1341                 param = kvm_register_read(vcpu, VCPU_REGS_RCX);
1342                 ingpa = kvm_register_read(vcpu, VCPU_REGS_RDX);
1343                 outgpa = kvm_register_read(vcpu, VCPU_REGS_R8);
1344         }
1345 #endif
1346
1347         code = param & 0xffff;
1348         fast = (param >> 16) & 0x1;
1349         rep_cnt = (param >> 32) & 0xfff;
1350         rep_idx = (param >> 48) & 0xfff;
1351
1352         trace_kvm_hv_hypercall(code, fast, rep_cnt, rep_idx, ingpa, outgpa);
1353
1354         /* Hypercall continuation is not supported yet */
1355         if (rep_cnt || rep_idx) {
1356                 ret = HV_STATUS_INVALID_HYPERCALL_CODE;
1357                 goto out;
1358         }
1359
1360         switch (code) {
1361         case HVCALL_NOTIFY_LONG_SPIN_WAIT:
1362                 kvm_vcpu_on_spin(vcpu, true);
1363                 break;
1364         case HVCALL_SIGNAL_EVENT:
1365                 ret = kvm_hvcall_signal_event(vcpu, fast, ingpa);
1366                 if (ret != HV_STATUS_INVALID_PORT_ID)
1367                         break;
1368                 /* maybe userspace knows this conn_id: fall through */
1369         case HVCALL_POST_MESSAGE:
1370                 /* don't bother userspace if it has no way to handle it */
1371                 if (!vcpu_to_synic(vcpu)->active) {
1372                         ret = HV_STATUS_INVALID_HYPERCALL_CODE;
1373                         break;
1374                 }
1375                 vcpu->run->exit_reason = KVM_EXIT_HYPERV;
1376                 vcpu->run->hyperv.type = KVM_EXIT_HYPERV_HCALL;
1377                 vcpu->run->hyperv.u.hcall.input = param;
1378                 vcpu->run->hyperv.u.hcall.params[0] = ingpa;
1379                 vcpu->run->hyperv.u.hcall.params[1] = outgpa;
1380                 vcpu->arch.complete_userspace_io =
1381                                 kvm_hv_hypercall_complete_userspace;
1382                 return 0;
1383         default:
1384                 ret = HV_STATUS_INVALID_HYPERCALL_CODE;
1385                 break;
1386         }
1387
1388 out:
1389         return kvm_hv_hypercall_complete(vcpu, ret);
1390 }
1391
1392 void kvm_hv_init_vm(struct kvm *kvm)
1393 {
1394         mutex_init(&kvm->arch.hyperv.hv_lock);
1395         idr_init(&kvm->arch.hyperv.conn_to_evt);
1396 }
1397
1398 void kvm_hv_destroy_vm(struct kvm *kvm)
1399 {
1400         struct eventfd_ctx *eventfd;
1401         int i;
1402
1403         idr_for_each_entry(&kvm->arch.hyperv.conn_to_evt, eventfd, i)
1404                 eventfd_ctx_put(eventfd);
1405         idr_destroy(&kvm->arch.hyperv.conn_to_evt);
1406 }
1407
1408 static int kvm_hv_eventfd_assign(struct kvm *kvm, u32 conn_id, int fd)
1409 {
1410         struct kvm_hv *hv = &kvm->arch.hyperv;
1411         struct eventfd_ctx *eventfd;
1412         int ret;
1413
1414         eventfd = eventfd_ctx_fdget(fd);
1415         if (IS_ERR(eventfd))
1416                 return PTR_ERR(eventfd);
1417
1418         mutex_lock(&hv->hv_lock);
1419         ret = idr_alloc(&hv->conn_to_evt, eventfd, conn_id, conn_id + 1,
1420                         GFP_KERNEL);
1421         mutex_unlock(&hv->hv_lock);
1422
1423         if (ret >= 0)
1424                 return 0;
1425
1426         if (ret == -ENOSPC)
1427                 ret = -EEXIST;
1428         eventfd_ctx_put(eventfd);
1429         return ret;
1430 }
1431
1432 static int kvm_hv_eventfd_deassign(struct kvm *kvm, u32 conn_id)
1433 {
1434         struct kvm_hv *hv = &kvm->arch.hyperv;
1435         struct eventfd_ctx *eventfd;
1436
1437         mutex_lock(&hv->hv_lock);
1438         eventfd = idr_remove(&hv->conn_to_evt, conn_id);
1439         mutex_unlock(&hv->hv_lock);
1440
1441         if (!eventfd)
1442                 return -ENOENT;
1443
1444         synchronize_srcu(&kvm->srcu);
1445         eventfd_ctx_put(eventfd);
1446         return 0;
1447 }
1448
1449 int kvm_vm_ioctl_hv_eventfd(struct kvm *kvm, struct kvm_hyperv_eventfd *args)
1450 {
1451         if ((args->flags & ~KVM_HYPERV_EVENTFD_DEASSIGN) ||
1452             (args->conn_id & ~KVM_HYPERV_CONN_ID_MASK))
1453                 return -EINVAL;
1454
1455         if (args->flags == KVM_HYPERV_EVENTFD_DEASSIGN)
1456                 return kvm_hv_eventfd_deassign(kvm, args->conn_id);
1457         return kvm_hv_eventfd_assign(kvm, args->conn_id, args->fd);
1458 }