KVM: Move apic timer migration away from critical section
[sfrench/cifs-2.6.git] / arch / x86 / kvm / lapic.c
1
2 /*
3  * Local APIC virtualization
4  *
5  * Copyright (C) 2006 Qumranet, Inc.
6  * Copyright (C) 2007 Novell
7  * Copyright (C) 2007 Intel
8  *
9  * Authors:
10  *   Dor Laor <dor.laor@qumranet.com>
11  *   Gregory Haskins <ghaskins@novell.com>
12  *   Yaozu (Eddie) Dong <eddie.dong@intel.com>
13  *
14  * Based on Xen 3.1 code, Copyright (c) 2004, Intel Corporation.
15  *
16  * This work is licensed under the terms of the GNU GPL, version 2.  See
17  * the COPYING file in the top-level directory.
18  */
19
20 #include <linux/kvm_host.h>
21 #include <linux/kvm.h>
22 #include <linux/mm.h>
23 #include <linux/highmem.h>
24 #include <linux/smp.h>
25 #include <linux/hrtimer.h>
26 #include <linux/io.h>
27 #include <linux/module.h>
28 #include <asm/processor.h>
29 #include <asm/msr.h>
30 #include <asm/page.h>
31 #include <asm/current.h>
32 #include <asm/apicdef.h>
33 #include <asm/atomic.h>
34 #include <asm/div64.h>
35 #include "irq.h"
36
37 #define PRId64 "d"
38 #define PRIx64 "llx"
39 #define PRIu64 "u"
40 #define PRIo64 "o"
41
42 #define APIC_BUS_CYCLE_NS 1
43
44 /* #define apic_debug(fmt,arg...) printk(KERN_WARNING fmt,##arg) */
45 #define apic_debug(fmt, arg...)
46
47 #define APIC_LVT_NUM                    6
48 /* 14 is the version for Xeon and Pentium 8.4.8*/
49 #define APIC_VERSION                    (0x14UL | ((APIC_LVT_NUM - 1) << 16))
50 #define LAPIC_MMIO_LENGTH               (1 << 12)
51 /* followed define is not in apicdef.h */
52 #define APIC_SHORT_MASK                 0xc0000
53 #define APIC_DEST_NOSHORT               0x0
54 #define APIC_DEST_MASK                  0x800
55 #define MAX_APIC_VECTOR                 256
56
57 #define VEC_POS(v) ((v) & (32 - 1))
58 #define REG_POS(v) (((v) >> 5) << 4)
59
60 static inline u32 apic_get_reg(struct kvm_lapic *apic, int reg_off)
61 {
62         return *((u32 *) (apic->regs + reg_off));
63 }
64
65 static inline void apic_set_reg(struct kvm_lapic *apic, int reg_off, u32 val)
66 {
67         *((u32 *) (apic->regs + reg_off)) = val;
68 }
69
70 static inline int apic_test_and_set_vector(int vec, void *bitmap)
71 {
72         return test_and_set_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
73 }
74
75 static inline int apic_test_and_clear_vector(int vec, void *bitmap)
76 {
77         return test_and_clear_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
78 }
79
80 static inline void apic_set_vector(int vec, void *bitmap)
81 {
82         set_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
83 }
84
85 static inline void apic_clear_vector(int vec, void *bitmap)
86 {
87         clear_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
88 }
89
90 static inline int apic_hw_enabled(struct kvm_lapic *apic)
91 {
92         return (apic)->vcpu->arch.apic_base & MSR_IA32_APICBASE_ENABLE;
93 }
94
95 static inline int  apic_sw_enabled(struct kvm_lapic *apic)
96 {
97         return apic_get_reg(apic, APIC_SPIV) & APIC_SPIV_APIC_ENABLED;
98 }
99
100 static inline int apic_enabled(struct kvm_lapic *apic)
101 {
102         return apic_sw_enabled(apic) && apic_hw_enabled(apic);
103 }
104
105 #define LVT_MASK        \
106         (APIC_LVT_MASKED | APIC_SEND_PENDING | APIC_VECTOR_MASK)
107
108 #define LINT_MASK       \
109         (LVT_MASK | APIC_MODE_MASK | APIC_INPUT_POLARITY | \
110          APIC_LVT_REMOTE_IRR | APIC_LVT_LEVEL_TRIGGER)
111
112 static inline int kvm_apic_id(struct kvm_lapic *apic)
113 {
114         return (apic_get_reg(apic, APIC_ID) >> 24) & 0xff;
115 }
116
117 static inline int apic_lvt_enabled(struct kvm_lapic *apic, int lvt_type)
118 {
119         return !(apic_get_reg(apic, lvt_type) & APIC_LVT_MASKED);
120 }
121
122 static inline int apic_lvt_vector(struct kvm_lapic *apic, int lvt_type)
123 {
124         return apic_get_reg(apic, lvt_type) & APIC_VECTOR_MASK;
125 }
126
127 static inline int apic_lvtt_period(struct kvm_lapic *apic)
128 {
129         return apic_get_reg(apic, APIC_LVTT) & APIC_LVT_TIMER_PERIODIC;
130 }
131
132 static unsigned int apic_lvt_mask[APIC_LVT_NUM] = {
133         LVT_MASK | APIC_LVT_TIMER_PERIODIC,     /* LVTT */
134         LVT_MASK | APIC_MODE_MASK,      /* LVTTHMR */
135         LVT_MASK | APIC_MODE_MASK,      /* LVTPC */
136         LINT_MASK, LINT_MASK,   /* LVT0-1 */
137         LVT_MASK                /* LVTERR */
138 };
139
140 static int find_highest_vector(void *bitmap)
141 {
142         u32 *word = bitmap;
143         int word_offset = MAX_APIC_VECTOR >> 5;
144
145         while ((word_offset != 0) && (word[(--word_offset) << 2] == 0))
146                 continue;
147
148         if (likely(!word_offset && !word[0]))
149                 return -1;
150         else
151                 return fls(word[word_offset << 2]) - 1 + (word_offset << 5);
152 }
153
154 static inline int apic_test_and_set_irr(int vec, struct kvm_lapic *apic)
155 {
156         return apic_test_and_set_vector(vec, apic->regs + APIC_IRR);
157 }
158
159 static inline void apic_clear_irr(int vec, struct kvm_lapic *apic)
160 {
161         apic_clear_vector(vec, apic->regs + APIC_IRR);
162 }
163
164 static inline int apic_find_highest_irr(struct kvm_lapic *apic)
165 {
166         int result;
167
168         result = find_highest_vector(apic->regs + APIC_IRR);
169         ASSERT(result == -1 || result >= 16);
170
171         return result;
172 }
173
174 int kvm_lapic_find_highest_irr(struct kvm_vcpu *vcpu)
175 {
176         struct kvm_lapic *apic = vcpu->arch.apic;
177         int highest_irr;
178
179         if (!apic)
180                 return 0;
181         highest_irr = apic_find_highest_irr(apic);
182
183         return highest_irr;
184 }
185 EXPORT_SYMBOL_GPL(kvm_lapic_find_highest_irr);
186
187 int kvm_apic_set_irq(struct kvm_vcpu *vcpu, u8 vec, u8 trig)
188 {
189         struct kvm_lapic *apic = vcpu->arch.apic;
190
191         if (!apic_test_and_set_irr(vec, apic)) {
192                 /* a new pending irq is set in IRR */
193                 if (trig)
194                         apic_set_vector(vec, apic->regs + APIC_TMR);
195                 else
196                         apic_clear_vector(vec, apic->regs + APIC_TMR);
197                 kvm_vcpu_kick(apic->vcpu);
198                 return 1;
199         }
200         return 0;
201 }
202
203 static inline int apic_find_highest_isr(struct kvm_lapic *apic)
204 {
205         int result;
206
207         result = find_highest_vector(apic->regs + APIC_ISR);
208         ASSERT(result == -1 || result >= 16);
209
210         return result;
211 }
212
213 static void apic_update_ppr(struct kvm_lapic *apic)
214 {
215         u32 tpr, isrv, ppr;
216         int isr;
217
218         tpr = apic_get_reg(apic, APIC_TASKPRI);
219         isr = apic_find_highest_isr(apic);
220         isrv = (isr != -1) ? isr : 0;
221
222         if ((tpr & 0xf0) >= (isrv & 0xf0))
223                 ppr = tpr & 0xff;
224         else
225                 ppr = isrv & 0xf0;
226
227         apic_debug("vlapic %p, ppr 0x%x, isr 0x%x, isrv 0x%x",
228                    apic, ppr, isr, isrv);
229
230         apic_set_reg(apic, APIC_PROCPRI, ppr);
231 }
232
233 static void apic_set_tpr(struct kvm_lapic *apic, u32 tpr)
234 {
235         apic_set_reg(apic, APIC_TASKPRI, tpr);
236         apic_update_ppr(apic);
237 }
238
239 int kvm_apic_match_physical_addr(struct kvm_lapic *apic, u16 dest)
240 {
241         return kvm_apic_id(apic) == dest;
242 }
243
244 int kvm_apic_match_logical_addr(struct kvm_lapic *apic, u8 mda)
245 {
246         int result = 0;
247         u8 logical_id;
248
249         logical_id = GET_APIC_LOGICAL_ID(apic_get_reg(apic, APIC_LDR));
250
251         switch (apic_get_reg(apic, APIC_DFR)) {
252         case APIC_DFR_FLAT:
253                 if (logical_id & mda)
254                         result = 1;
255                 break;
256         case APIC_DFR_CLUSTER:
257                 if (((logical_id >> 4) == (mda >> 0x4))
258                     && (logical_id & mda & 0xf))
259                         result = 1;
260                 break;
261         default:
262                 printk(KERN_WARNING "Bad DFR vcpu %d: %08x\n",
263                        apic->vcpu->vcpu_id, apic_get_reg(apic, APIC_DFR));
264                 break;
265         }
266
267         return result;
268 }
269
270 static int apic_match_dest(struct kvm_vcpu *vcpu, struct kvm_lapic *source,
271                            int short_hand, int dest, int dest_mode)
272 {
273         int result = 0;
274         struct kvm_lapic *target = vcpu->arch.apic;
275
276         apic_debug("target %p, source %p, dest 0x%x, "
277                    "dest_mode 0x%x, short_hand 0x%x",
278                    target, source, dest, dest_mode, short_hand);
279
280         ASSERT(!target);
281         switch (short_hand) {
282         case APIC_DEST_NOSHORT:
283                 if (dest_mode == 0) {
284                         /* Physical mode. */
285                         if ((dest == 0xFF) || (dest == kvm_apic_id(target)))
286                                 result = 1;
287                 } else
288                         /* Logical mode. */
289                         result = kvm_apic_match_logical_addr(target, dest);
290                 break;
291         case APIC_DEST_SELF:
292                 if (target == source)
293                         result = 1;
294                 break;
295         case APIC_DEST_ALLINC:
296                 result = 1;
297                 break;
298         case APIC_DEST_ALLBUT:
299                 if (target != source)
300                         result = 1;
301                 break;
302         default:
303                 printk(KERN_WARNING "Bad dest shorthand value %x\n",
304                        short_hand);
305                 break;
306         }
307
308         return result;
309 }
310
311 /*
312  * Add a pending IRQ into lapic.
313  * Return 1 if successfully added and 0 if discarded.
314  */
315 static int __apic_accept_irq(struct kvm_lapic *apic, int delivery_mode,
316                              int vector, int level, int trig_mode)
317 {
318         int orig_irr, result = 0;
319         struct kvm_vcpu *vcpu = apic->vcpu;
320
321         switch (delivery_mode) {
322         case APIC_DM_FIXED:
323         case APIC_DM_LOWEST:
324                 /* FIXME add logic for vcpu on reset */
325                 if (unlikely(!apic_enabled(apic)))
326                         break;
327
328                 orig_irr = apic_test_and_set_irr(vector, apic);
329                 if (orig_irr && trig_mode) {
330                         apic_debug("level trig mode repeatedly for vector %d",
331                                    vector);
332                         break;
333                 }
334
335                 if (trig_mode) {
336                         apic_debug("level trig mode for vector %d", vector);
337                         apic_set_vector(vector, apic->regs + APIC_TMR);
338                 } else
339                         apic_clear_vector(vector, apic->regs + APIC_TMR);
340
341                 if (vcpu->arch.mp_state == VCPU_MP_STATE_RUNNABLE)
342                         kvm_vcpu_kick(vcpu);
343                 else if (vcpu->arch.mp_state == VCPU_MP_STATE_HALTED) {
344                         vcpu->arch.mp_state = VCPU_MP_STATE_RUNNABLE;
345                         if (waitqueue_active(&vcpu->wq))
346                                 wake_up_interruptible(&vcpu->wq);
347                 }
348
349                 result = (orig_irr == 0);
350                 break;
351
352         case APIC_DM_REMRD:
353                 printk(KERN_DEBUG "Ignoring delivery mode 3\n");
354                 break;
355
356         case APIC_DM_SMI:
357                 printk(KERN_DEBUG "Ignoring guest SMI\n");
358                 break;
359         case APIC_DM_NMI:
360                 printk(KERN_DEBUG "Ignoring guest NMI\n");
361                 break;
362
363         case APIC_DM_INIT:
364                 if (level) {
365                         if (vcpu->arch.mp_state == VCPU_MP_STATE_RUNNABLE)
366                                 printk(KERN_DEBUG
367                                        "INIT on a runnable vcpu %d\n",
368                                        vcpu->vcpu_id);
369                         vcpu->arch.mp_state = VCPU_MP_STATE_INIT_RECEIVED;
370                         kvm_vcpu_kick(vcpu);
371                 } else {
372                         printk(KERN_DEBUG
373                                "Ignoring de-assert INIT to vcpu %d\n",
374                                vcpu->vcpu_id);
375                 }
376
377                 break;
378
379         case APIC_DM_STARTUP:
380                 printk(KERN_DEBUG "SIPI to vcpu %d vector 0x%02x\n",
381                        vcpu->vcpu_id, vector);
382                 if (vcpu->arch.mp_state == VCPU_MP_STATE_INIT_RECEIVED) {
383                         vcpu->arch.sipi_vector = vector;
384                         vcpu->arch.mp_state = VCPU_MP_STATE_SIPI_RECEIVED;
385                         if (waitqueue_active(&vcpu->wq))
386                                 wake_up_interruptible(&vcpu->wq);
387                 }
388                 break;
389
390         default:
391                 printk(KERN_ERR "TODO: unsupported delivery mode %x\n",
392                        delivery_mode);
393                 break;
394         }
395         return result;
396 }
397
398 static struct kvm_lapic *kvm_apic_round_robin(struct kvm *kvm, u8 vector,
399                                        unsigned long bitmap)
400 {
401         int last;
402         int next;
403         struct kvm_lapic *apic = NULL;
404
405         last = kvm->arch.round_robin_prev_vcpu;
406         next = last;
407
408         do {
409                 if (++next == KVM_MAX_VCPUS)
410                         next = 0;
411                 if (kvm->vcpus[next] == NULL || !test_bit(next, &bitmap))
412                         continue;
413                 apic = kvm->vcpus[next]->arch.apic;
414                 if (apic && apic_enabled(apic))
415                         break;
416                 apic = NULL;
417         } while (next != last);
418         kvm->arch.round_robin_prev_vcpu = next;
419
420         if (!apic)
421                 printk(KERN_DEBUG "vcpu not ready for apic_round_robin\n");
422
423         return apic;
424 }
425
426 struct kvm_vcpu *kvm_get_lowest_prio_vcpu(struct kvm *kvm, u8 vector,
427                 unsigned long bitmap)
428 {
429         struct kvm_lapic *apic;
430
431         apic = kvm_apic_round_robin(kvm, vector, bitmap);
432         if (apic)
433                 return apic->vcpu;
434         return NULL;
435 }
436
437 static void apic_set_eoi(struct kvm_lapic *apic)
438 {
439         int vector = apic_find_highest_isr(apic);
440
441         /*
442          * Not every write EOI will has corresponding ISR,
443          * one example is when Kernel check timer on setup_IO_APIC
444          */
445         if (vector == -1)
446                 return;
447
448         apic_clear_vector(vector, apic->regs + APIC_ISR);
449         apic_update_ppr(apic);
450
451         if (apic_test_and_clear_vector(vector, apic->regs + APIC_TMR))
452                 kvm_ioapic_update_eoi(apic->vcpu->kvm, vector);
453 }
454
455 static void apic_send_ipi(struct kvm_lapic *apic)
456 {
457         u32 icr_low = apic_get_reg(apic, APIC_ICR);
458         u32 icr_high = apic_get_reg(apic, APIC_ICR2);
459
460         unsigned int dest = GET_APIC_DEST_FIELD(icr_high);
461         unsigned int short_hand = icr_low & APIC_SHORT_MASK;
462         unsigned int trig_mode = icr_low & APIC_INT_LEVELTRIG;
463         unsigned int level = icr_low & APIC_INT_ASSERT;
464         unsigned int dest_mode = icr_low & APIC_DEST_MASK;
465         unsigned int delivery_mode = icr_low & APIC_MODE_MASK;
466         unsigned int vector = icr_low & APIC_VECTOR_MASK;
467
468         struct kvm_vcpu *target;
469         struct kvm_vcpu *vcpu;
470         unsigned long lpr_map = 0;
471         int i;
472
473         apic_debug("icr_high 0x%x, icr_low 0x%x, "
474                    "short_hand 0x%x, dest 0x%x, trig_mode 0x%x, level 0x%x, "
475                    "dest_mode 0x%x, delivery_mode 0x%x, vector 0x%x\n",
476                    icr_high, icr_low, short_hand, dest,
477                    trig_mode, level, dest_mode, delivery_mode, vector);
478
479         for (i = 0; i < KVM_MAX_VCPUS; i++) {
480                 vcpu = apic->vcpu->kvm->vcpus[i];
481                 if (!vcpu)
482                         continue;
483
484                 if (vcpu->arch.apic &&
485                     apic_match_dest(vcpu, apic, short_hand, dest, dest_mode)) {
486                         if (delivery_mode == APIC_DM_LOWEST)
487                                 set_bit(vcpu->vcpu_id, &lpr_map);
488                         else
489                                 __apic_accept_irq(vcpu->arch.apic, delivery_mode,
490                                                   vector, level, trig_mode);
491                 }
492         }
493
494         if (delivery_mode == APIC_DM_LOWEST) {
495                 target = kvm_get_lowest_prio_vcpu(vcpu->kvm, vector, lpr_map);
496                 if (target != NULL)
497                         __apic_accept_irq(target->arch.apic, delivery_mode,
498                                           vector, level, trig_mode);
499         }
500 }
501
502 static u32 apic_get_tmcct(struct kvm_lapic *apic)
503 {
504         u64 counter_passed;
505         ktime_t passed, now;
506         u32 tmcct;
507
508         ASSERT(apic != NULL);
509
510         now = apic->timer.dev.base->get_time();
511         tmcct = apic_get_reg(apic, APIC_TMICT);
512
513         /* if initial count is 0, current count should also be 0 */
514         if (tmcct == 0)
515                 return 0;
516
517         if (unlikely(ktime_to_ns(now) <=
518                 ktime_to_ns(apic->timer.last_update))) {
519                 /* Wrap around */
520                 passed = ktime_add(( {
521                                     (ktime_t) {
522                                     .tv64 = KTIME_MAX -
523                                     (apic->timer.last_update).tv64}; }
524                                    ), now);
525                 apic_debug("time elapsed\n");
526         } else
527                 passed = ktime_sub(now, apic->timer.last_update);
528
529         counter_passed = div64_64(ktime_to_ns(passed),
530                                   (APIC_BUS_CYCLE_NS * apic->timer.divide_count));
531
532         if (counter_passed > tmcct) {
533                 if (unlikely(!apic_lvtt_period(apic))) {
534                         /* one-shot timers stick at 0 until reset */
535                         tmcct = 0;
536                 } else {
537                         /*
538                          * periodic timers reset to APIC_TMICT when they
539                          * hit 0. The while loop simulates this happening N
540                          * times. (counter_passed %= tmcct) would also work,
541                          * but might be slower or not work on 32-bit??
542                          */
543                         while (counter_passed > tmcct)
544                                 counter_passed -= tmcct;
545                         tmcct -= counter_passed;
546                 }
547         } else {
548                 tmcct -= counter_passed;
549         }
550
551         return tmcct;
552 }
553
554 static void __report_tpr_access(struct kvm_lapic *apic, bool write)
555 {
556         struct kvm_vcpu *vcpu = apic->vcpu;
557         struct kvm_run *run = vcpu->run;
558
559         set_bit(KVM_REQ_REPORT_TPR_ACCESS, &vcpu->requests);
560         kvm_x86_ops->cache_regs(vcpu);
561         run->tpr_access.rip = vcpu->arch.rip;
562         run->tpr_access.is_write = write;
563 }
564
565 static inline void report_tpr_access(struct kvm_lapic *apic, bool write)
566 {
567         if (apic->vcpu->arch.tpr_access_reporting)
568                 __report_tpr_access(apic, write);
569 }
570
571 static u32 __apic_read(struct kvm_lapic *apic, unsigned int offset)
572 {
573         u32 val = 0;
574
575         if (offset >= LAPIC_MMIO_LENGTH)
576                 return 0;
577
578         switch (offset) {
579         case APIC_ARBPRI:
580                 printk(KERN_WARNING "Access APIC ARBPRI register "
581                        "which is for P6\n");
582                 break;
583
584         case APIC_TMCCT:        /* Timer CCR */
585                 val = apic_get_tmcct(apic);
586                 break;
587
588         case APIC_TASKPRI:
589                 report_tpr_access(apic, false);
590                 /* fall thru */
591         default:
592                 apic_update_ppr(apic);
593                 val = apic_get_reg(apic, offset);
594                 break;
595         }
596
597         return val;
598 }
599
600 static void apic_mmio_read(struct kvm_io_device *this,
601                            gpa_t address, int len, void *data)
602 {
603         struct kvm_lapic *apic = (struct kvm_lapic *)this->private;
604         unsigned int offset = address - apic->base_address;
605         unsigned char alignment = offset & 0xf;
606         u32 result;
607
608         if ((alignment + len) > 4) {
609                 printk(KERN_ERR "KVM_APIC_READ: alignment error %lx %d",
610                        (unsigned long)address, len);
611                 return;
612         }
613         result = __apic_read(apic, offset & ~0xf);
614
615         switch (len) {
616         case 1:
617         case 2:
618         case 4:
619                 memcpy(data, (char *)&result + alignment, len);
620                 break;
621         default:
622                 printk(KERN_ERR "Local APIC read with len = %x, "
623                        "should be 1,2, or 4 instead\n", len);
624                 break;
625         }
626 }
627
628 static void update_divide_count(struct kvm_lapic *apic)
629 {
630         u32 tmp1, tmp2, tdcr;
631
632         tdcr = apic_get_reg(apic, APIC_TDCR);
633         tmp1 = tdcr & 0xf;
634         tmp2 = ((tmp1 & 0x3) | ((tmp1 & 0x8) >> 1)) + 1;
635         apic->timer.divide_count = 0x1 << (tmp2 & 0x7);
636
637         apic_debug("timer divide count is 0x%x\n",
638                                    apic->timer.divide_count);
639 }
640
641 static void start_apic_timer(struct kvm_lapic *apic)
642 {
643         ktime_t now = apic->timer.dev.base->get_time();
644
645         apic->timer.last_update = now;
646
647         apic->timer.period = apic_get_reg(apic, APIC_TMICT) *
648                     APIC_BUS_CYCLE_NS * apic->timer.divide_count;
649         atomic_set(&apic->timer.pending, 0);
650         hrtimer_start(&apic->timer.dev,
651                       ktime_add_ns(now, apic->timer.period),
652                       HRTIMER_MODE_ABS);
653
654         apic_debug("%s: bus cycle is %" PRId64 "ns, now 0x%016"
655                            PRIx64 ", "
656                            "timer initial count 0x%x, period %lldns, "
657                            "expire @ 0x%016" PRIx64 ".\n", __FUNCTION__,
658                            APIC_BUS_CYCLE_NS, ktime_to_ns(now),
659                            apic_get_reg(apic, APIC_TMICT),
660                            apic->timer.period,
661                            ktime_to_ns(ktime_add_ns(now,
662                                         apic->timer.period)));
663 }
664
665 static void apic_mmio_write(struct kvm_io_device *this,
666                             gpa_t address, int len, const void *data)
667 {
668         struct kvm_lapic *apic = (struct kvm_lapic *)this->private;
669         unsigned int offset = address - apic->base_address;
670         unsigned char alignment = offset & 0xf;
671         u32 val;
672
673         /*
674          * APIC register must be aligned on 128-bits boundary.
675          * 32/64/128 bits registers must be accessed thru 32 bits.
676          * Refer SDM 8.4.1
677          */
678         if (len != 4 || alignment) {
679                 if (printk_ratelimit())
680                         printk(KERN_ERR "apic write: bad size=%d %lx\n",
681                                len, (long)address);
682                 return;
683         }
684
685         val = *(u32 *) data;
686
687         /* too common printing */
688         if (offset != APIC_EOI)
689                 apic_debug("%s: offset 0x%x with length 0x%x, and value is "
690                            "0x%x\n", __FUNCTION__, offset, len, val);
691
692         offset &= 0xff0;
693
694         switch (offset) {
695         case APIC_ID:           /* Local APIC ID */
696                 apic_set_reg(apic, APIC_ID, val);
697                 break;
698
699         case APIC_TASKPRI:
700                 report_tpr_access(apic, true);
701                 apic_set_tpr(apic, val & 0xff);
702                 break;
703
704         case APIC_EOI:
705                 apic_set_eoi(apic);
706                 break;
707
708         case APIC_LDR:
709                 apic_set_reg(apic, APIC_LDR, val & APIC_LDR_MASK);
710                 break;
711
712         case APIC_DFR:
713                 apic_set_reg(apic, APIC_DFR, val | 0x0FFFFFFF);
714                 break;
715
716         case APIC_SPIV:
717                 apic_set_reg(apic, APIC_SPIV, val & 0x3ff);
718                 if (!(val & APIC_SPIV_APIC_ENABLED)) {
719                         int i;
720                         u32 lvt_val;
721
722                         for (i = 0; i < APIC_LVT_NUM; i++) {
723                                 lvt_val = apic_get_reg(apic,
724                                                        APIC_LVTT + 0x10 * i);
725                                 apic_set_reg(apic, APIC_LVTT + 0x10 * i,
726                                              lvt_val | APIC_LVT_MASKED);
727                         }
728                         atomic_set(&apic->timer.pending, 0);
729
730                 }
731                 break;
732
733         case APIC_ICR:
734                 /* No delay here, so we always clear the pending bit */
735                 apic_set_reg(apic, APIC_ICR, val & ~(1 << 12));
736                 apic_send_ipi(apic);
737                 break;
738
739         case APIC_ICR2:
740                 apic_set_reg(apic, APIC_ICR2, val & 0xff000000);
741                 break;
742
743         case APIC_LVTT:
744         case APIC_LVTTHMR:
745         case APIC_LVTPC:
746         case APIC_LVT0:
747         case APIC_LVT1:
748         case APIC_LVTERR:
749                 /* TODO: Check vector */
750                 if (!apic_sw_enabled(apic))
751                         val |= APIC_LVT_MASKED;
752
753                 val &= apic_lvt_mask[(offset - APIC_LVTT) >> 4];
754                 apic_set_reg(apic, offset, val);
755
756                 break;
757
758         case APIC_TMICT:
759                 hrtimer_cancel(&apic->timer.dev);
760                 apic_set_reg(apic, APIC_TMICT, val);
761                 start_apic_timer(apic);
762                 return;
763
764         case APIC_TDCR:
765                 if (val & 4)
766                         printk(KERN_ERR "KVM_WRITE:TDCR %x\n", val);
767                 apic_set_reg(apic, APIC_TDCR, val);
768                 update_divide_count(apic);
769                 break;
770
771         default:
772                 apic_debug("Local APIC Write to read-only register %x\n",
773                            offset);
774                 break;
775         }
776
777 }
778
779 static int apic_mmio_range(struct kvm_io_device *this, gpa_t addr)
780 {
781         struct kvm_lapic *apic = (struct kvm_lapic *)this->private;
782         int ret = 0;
783
784
785         if (apic_hw_enabled(apic) &&
786             (addr >= apic->base_address) &&
787             (addr < (apic->base_address + LAPIC_MMIO_LENGTH)))
788                 ret = 1;
789
790         return ret;
791 }
792
793 void kvm_free_lapic(struct kvm_vcpu *vcpu)
794 {
795         if (!vcpu->arch.apic)
796                 return;
797
798         hrtimer_cancel(&vcpu->arch.apic->timer.dev);
799
800         if (vcpu->arch.apic->regs_page)
801                 __free_page(vcpu->arch.apic->regs_page);
802
803         kfree(vcpu->arch.apic);
804 }
805
806 /*
807  *----------------------------------------------------------------------
808  * LAPIC interface
809  *----------------------------------------------------------------------
810  */
811
812 void kvm_lapic_set_tpr(struct kvm_vcpu *vcpu, unsigned long cr8)
813 {
814         struct kvm_lapic *apic = vcpu->arch.apic;
815
816         if (!apic)
817                 return;
818         apic_set_tpr(apic, ((cr8 & 0x0f) << 4)
819                      | (apic_get_reg(apic, APIC_TASKPRI) & 4));
820 }
821
822 u64 kvm_lapic_get_cr8(struct kvm_vcpu *vcpu)
823 {
824         struct kvm_lapic *apic = vcpu->arch.apic;
825         u64 tpr;
826
827         if (!apic)
828                 return 0;
829         tpr = (u64) apic_get_reg(apic, APIC_TASKPRI);
830
831         return (tpr & 0xf0) >> 4;
832 }
833 EXPORT_SYMBOL_GPL(kvm_lapic_get_cr8);
834
835 void kvm_lapic_set_base(struct kvm_vcpu *vcpu, u64 value)
836 {
837         struct kvm_lapic *apic = vcpu->arch.apic;
838
839         if (!apic) {
840                 value |= MSR_IA32_APICBASE_BSP;
841                 vcpu->arch.apic_base = value;
842                 return;
843         }
844         if (apic->vcpu->vcpu_id)
845                 value &= ~MSR_IA32_APICBASE_BSP;
846
847         vcpu->arch.apic_base = value;
848         apic->base_address = apic->vcpu->arch.apic_base &
849                              MSR_IA32_APICBASE_BASE;
850
851         /* with FSB delivery interrupt, we can restart APIC functionality */
852         apic_debug("apic base msr is 0x%016" PRIx64 ", and base address is "
853                    "0x%lx.\n", apic->vcpu->arch.apic_base, apic->base_address);
854
855 }
856
857 u64 kvm_lapic_get_base(struct kvm_vcpu *vcpu)
858 {
859         return vcpu->arch.apic_base;
860 }
861 EXPORT_SYMBOL_GPL(kvm_lapic_get_base);
862
863 void kvm_lapic_reset(struct kvm_vcpu *vcpu)
864 {
865         struct kvm_lapic *apic;
866         int i;
867
868         apic_debug("%s\n", __FUNCTION__);
869
870         ASSERT(vcpu);
871         apic = vcpu->arch.apic;
872         ASSERT(apic != NULL);
873
874         /* Stop the timer in case it's a reset to an active apic */
875         hrtimer_cancel(&apic->timer.dev);
876
877         apic_set_reg(apic, APIC_ID, vcpu->vcpu_id << 24);
878         apic_set_reg(apic, APIC_LVR, APIC_VERSION);
879
880         for (i = 0; i < APIC_LVT_NUM; i++)
881                 apic_set_reg(apic, APIC_LVTT + 0x10 * i, APIC_LVT_MASKED);
882         apic_set_reg(apic, APIC_LVT0,
883                      SET_APIC_DELIVERY_MODE(0, APIC_MODE_EXTINT));
884
885         apic_set_reg(apic, APIC_DFR, 0xffffffffU);
886         apic_set_reg(apic, APIC_SPIV, 0xff);
887         apic_set_reg(apic, APIC_TASKPRI, 0);
888         apic_set_reg(apic, APIC_LDR, 0);
889         apic_set_reg(apic, APIC_ESR, 0);
890         apic_set_reg(apic, APIC_ICR, 0);
891         apic_set_reg(apic, APIC_ICR2, 0);
892         apic_set_reg(apic, APIC_TDCR, 0);
893         apic_set_reg(apic, APIC_TMICT, 0);
894         for (i = 0; i < 8; i++) {
895                 apic_set_reg(apic, APIC_IRR + 0x10 * i, 0);
896                 apic_set_reg(apic, APIC_ISR + 0x10 * i, 0);
897                 apic_set_reg(apic, APIC_TMR + 0x10 * i, 0);
898         }
899         update_divide_count(apic);
900         atomic_set(&apic->timer.pending, 0);
901         if (vcpu->vcpu_id == 0)
902                 vcpu->arch.apic_base |= MSR_IA32_APICBASE_BSP;
903         apic_update_ppr(apic);
904
905         apic_debug(KERN_INFO "%s: vcpu=%p, id=%d, base_msr="
906                    "0x%016" PRIx64 ", base_address=0x%0lx.\n", __FUNCTION__,
907                    vcpu, kvm_apic_id(apic),
908                    vcpu->arch.apic_base, apic->base_address);
909 }
910 EXPORT_SYMBOL_GPL(kvm_lapic_reset);
911
912 int kvm_lapic_enabled(struct kvm_vcpu *vcpu)
913 {
914         struct kvm_lapic *apic = vcpu->arch.apic;
915         int ret = 0;
916
917         if (!apic)
918                 return 0;
919         ret = apic_enabled(apic);
920
921         return ret;
922 }
923 EXPORT_SYMBOL_GPL(kvm_lapic_enabled);
924
925 /*
926  *----------------------------------------------------------------------
927  * timer interface
928  *----------------------------------------------------------------------
929  */
930
931 /* TODO: make sure __apic_timer_fn runs in current pCPU */
932 static int __apic_timer_fn(struct kvm_lapic *apic)
933 {
934         int result = 0;
935         wait_queue_head_t *q = &apic->vcpu->wq;
936
937         atomic_inc(&apic->timer.pending);
938         if (waitqueue_active(q)) {
939                 apic->vcpu->arch.mp_state = VCPU_MP_STATE_RUNNABLE;
940                 wake_up_interruptible(q);
941         }
942         if (apic_lvtt_period(apic)) {
943                 result = 1;
944                 apic->timer.dev.expires = ktime_add_ns(
945                                         apic->timer.dev.expires,
946                                         apic->timer.period);
947         }
948         return result;
949 }
950
951 static int __inject_apic_timer_irq(struct kvm_lapic *apic)
952 {
953         int vector;
954
955         vector = apic_lvt_vector(apic, APIC_LVTT);
956         return __apic_accept_irq(apic, APIC_DM_FIXED, vector, 1, 0);
957 }
958
959 static enum hrtimer_restart apic_timer_fn(struct hrtimer *data)
960 {
961         struct kvm_lapic *apic;
962         int restart_timer = 0;
963
964         apic = container_of(data, struct kvm_lapic, timer.dev);
965
966         restart_timer = __apic_timer_fn(apic);
967
968         if (restart_timer)
969                 return HRTIMER_RESTART;
970         else
971                 return HRTIMER_NORESTART;
972 }
973
974 int kvm_create_lapic(struct kvm_vcpu *vcpu)
975 {
976         struct kvm_lapic *apic;
977
978         ASSERT(vcpu != NULL);
979         apic_debug("apic_init %d\n", vcpu->vcpu_id);
980
981         apic = kzalloc(sizeof(*apic), GFP_KERNEL);
982         if (!apic)
983                 goto nomem;
984
985         vcpu->arch.apic = apic;
986
987         apic->regs_page = alloc_page(GFP_KERNEL);
988         if (apic->regs_page == NULL) {
989                 printk(KERN_ERR "malloc apic regs error for vcpu %x\n",
990                        vcpu->vcpu_id);
991                 goto nomem_free_apic;
992         }
993         apic->regs = page_address(apic->regs_page);
994         memset(apic->regs, 0, PAGE_SIZE);
995         apic->vcpu = vcpu;
996
997         hrtimer_init(&apic->timer.dev, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
998         apic->timer.dev.function = apic_timer_fn;
999         apic->base_address = APIC_DEFAULT_PHYS_BASE;
1000         vcpu->arch.apic_base = APIC_DEFAULT_PHYS_BASE;
1001
1002         kvm_lapic_reset(vcpu);
1003         apic->dev.read = apic_mmio_read;
1004         apic->dev.write = apic_mmio_write;
1005         apic->dev.in_range = apic_mmio_range;
1006         apic->dev.private = apic;
1007
1008         return 0;
1009 nomem_free_apic:
1010         kfree(apic);
1011 nomem:
1012         return -ENOMEM;
1013 }
1014 EXPORT_SYMBOL_GPL(kvm_create_lapic);
1015
1016 int kvm_apic_has_interrupt(struct kvm_vcpu *vcpu)
1017 {
1018         struct kvm_lapic *apic = vcpu->arch.apic;
1019         int highest_irr;
1020
1021         if (!apic || !apic_enabled(apic))
1022                 return -1;
1023
1024         apic_update_ppr(apic);
1025         highest_irr = apic_find_highest_irr(apic);
1026         if ((highest_irr == -1) ||
1027             ((highest_irr & 0xF0) <= apic_get_reg(apic, APIC_PROCPRI)))
1028                 return -1;
1029         return highest_irr;
1030 }
1031
1032 int kvm_apic_accept_pic_intr(struct kvm_vcpu *vcpu)
1033 {
1034         u32 lvt0 = apic_get_reg(vcpu->arch.apic, APIC_LVT0);
1035         int r = 0;
1036
1037         if (vcpu->vcpu_id == 0) {
1038                 if (!apic_hw_enabled(vcpu->arch.apic))
1039                         r = 1;
1040                 if ((lvt0 & APIC_LVT_MASKED) == 0 &&
1041                     GET_APIC_DELIVERY_MODE(lvt0) == APIC_MODE_EXTINT)
1042                         r = 1;
1043         }
1044         return r;
1045 }
1046
1047 void kvm_inject_apic_timer_irqs(struct kvm_vcpu *vcpu)
1048 {
1049         struct kvm_lapic *apic = vcpu->arch.apic;
1050
1051         if (apic && apic_lvt_enabled(apic, APIC_LVTT) &&
1052                 atomic_read(&apic->timer.pending) > 0) {
1053                 if (__inject_apic_timer_irq(apic))
1054                         atomic_dec(&apic->timer.pending);
1055         }
1056 }
1057
1058 void kvm_apic_timer_intr_post(struct kvm_vcpu *vcpu, int vec)
1059 {
1060         struct kvm_lapic *apic = vcpu->arch.apic;
1061
1062         if (apic && apic_lvt_vector(apic, APIC_LVTT) == vec)
1063                 apic->timer.last_update = ktime_add_ns(
1064                                 apic->timer.last_update,
1065                                 apic->timer.period);
1066 }
1067
1068 int kvm_get_apic_interrupt(struct kvm_vcpu *vcpu)
1069 {
1070         int vector = kvm_apic_has_interrupt(vcpu);
1071         struct kvm_lapic *apic = vcpu->arch.apic;
1072
1073         if (vector == -1)
1074                 return -1;
1075
1076         apic_set_vector(vector, apic->regs + APIC_ISR);
1077         apic_update_ppr(apic);
1078         apic_clear_irr(vector, apic);
1079         return vector;
1080 }
1081
1082 void kvm_apic_post_state_restore(struct kvm_vcpu *vcpu)
1083 {
1084         struct kvm_lapic *apic = vcpu->arch.apic;
1085
1086         apic->base_address = vcpu->arch.apic_base &
1087                              MSR_IA32_APICBASE_BASE;
1088         apic_set_reg(apic, APIC_LVR, APIC_VERSION);
1089         apic_update_ppr(apic);
1090         hrtimer_cancel(&apic->timer.dev);
1091         update_divide_count(apic);
1092         start_apic_timer(apic);
1093 }
1094
1095 void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu)
1096 {
1097         struct kvm_lapic *apic = vcpu->arch.apic;
1098         struct hrtimer *timer;
1099
1100         if (!apic)
1101                 return;
1102
1103         timer = &apic->timer.dev;
1104         if (hrtimer_cancel(timer))
1105                 hrtimer_start(timer, timer->expires, HRTIMER_MODE_ABS);
1106 }
1107
1108 void kvm_lapic_sync_from_vapic(struct kvm_vcpu *vcpu)
1109 {
1110         u32 data;
1111         void *vapic;
1112
1113         if (!irqchip_in_kernel(vcpu->kvm) || !vcpu->arch.apic->vapic_addr)
1114                 return;
1115
1116         vapic = kmap_atomic(vcpu->arch.apic->vapic_page, KM_USER0);
1117         data = *(u32 *)(vapic + offset_in_page(vcpu->arch.apic->vapic_addr));
1118         kunmap_atomic(vapic, KM_USER0);
1119
1120         apic_set_tpr(vcpu->arch.apic, data & 0xff);
1121 }
1122
1123 void kvm_lapic_sync_to_vapic(struct kvm_vcpu *vcpu)
1124 {
1125         u32 data, tpr;
1126         int max_irr, max_isr;
1127         struct kvm_lapic *apic;
1128         void *vapic;
1129
1130         if (!irqchip_in_kernel(vcpu->kvm) || !vcpu->arch.apic->vapic_addr)
1131                 return;
1132
1133         apic = vcpu->arch.apic;
1134         tpr = apic_get_reg(apic, APIC_TASKPRI) & 0xff;
1135         max_irr = apic_find_highest_irr(apic);
1136         if (max_irr < 0)
1137                 max_irr = 0;
1138         max_isr = apic_find_highest_isr(apic);
1139         if (max_isr < 0)
1140                 max_isr = 0;
1141         data = (tpr & 0xff) | ((max_isr & 0xf0) << 8) | (max_irr << 24);
1142
1143         vapic = kmap_atomic(vcpu->arch.apic->vapic_page, KM_USER0);
1144         *(u32 *)(vapic + offset_in_page(vcpu->arch.apic->vapic_addr)) = data;
1145         kunmap_atomic(vapic, KM_USER0);
1146 }
1147
1148 void kvm_lapic_set_vapic_addr(struct kvm_vcpu *vcpu, gpa_t vapic_addr)
1149 {
1150         if (!irqchip_in_kernel(vcpu->kvm))
1151                 return;
1152
1153         vcpu->arch.apic->vapic_addr = vapic_addr;
1154 }