xref: /openbmc/linux/arch/x86/kvm/lapic.c (revision 545e4006)
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 <linux/math64.h>
29 #include <asm/processor.h>
30 #include <asm/msr.h>
31 #include <asm/page.h>
32 #include <asm/current.h>
33 #include <asm/apicdef.h>
34 #include <asm/atomic.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 == KVM_MP_STATE_RUNNABLE)
342 			kvm_vcpu_kick(vcpu);
343 		else if (vcpu->arch.mp_state == KVM_MP_STATE_HALTED) {
344 			vcpu->arch.mp_state = KVM_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 
360 	case APIC_DM_NMI:
361 		kvm_inject_nmi(vcpu);
362 		break;
363 
364 	case APIC_DM_INIT:
365 		if (level) {
366 			if (vcpu->arch.mp_state == KVM_MP_STATE_RUNNABLE)
367 				printk(KERN_DEBUG
368 				       "INIT on a runnable vcpu %d\n",
369 				       vcpu->vcpu_id);
370 			vcpu->arch.mp_state = KVM_MP_STATE_INIT_RECEIVED;
371 			kvm_vcpu_kick(vcpu);
372 		} else {
373 			printk(KERN_DEBUG
374 			       "Ignoring de-assert INIT to vcpu %d\n",
375 			       vcpu->vcpu_id);
376 		}
377 
378 		break;
379 
380 	case APIC_DM_STARTUP:
381 		printk(KERN_DEBUG "SIPI to vcpu %d vector 0x%02x\n",
382 		       vcpu->vcpu_id, vector);
383 		if (vcpu->arch.mp_state == KVM_MP_STATE_INIT_RECEIVED) {
384 			vcpu->arch.sipi_vector = vector;
385 			vcpu->arch.mp_state = KVM_MP_STATE_SIPI_RECEIVED;
386 			if (waitqueue_active(&vcpu->wq))
387 				wake_up_interruptible(&vcpu->wq);
388 		}
389 		break;
390 
391 	default:
392 		printk(KERN_ERR "TODO: unsupported delivery mode %x\n",
393 		       delivery_mode);
394 		break;
395 	}
396 	return result;
397 }
398 
399 static struct kvm_lapic *kvm_apic_round_robin(struct kvm *kvm, u8 vector,
400 				       unsigned long bitmap)
401 {
402 	int last;
403 	int next;
404 	struct kvm_lapic *apic = NULL;
405 
406 	last = kvm->arch.round_robin_prev_vcpu;
407 	next = last;
408 
409 	do {
410 		if (++next == KVM_MAX_VCPUS)
411 			next = 0;
412 		if (kvm->vcpus[next] == NULL || !test_bit(next, &bitmap))
413 			continue;
414 		apic = kvm->vcpus[next]->arch.apic;
415 		if (apic && apic_enabled(apic))
416 			break;
417 		apic = NULL;
418 	} while (next != last);
419 	kvm->arch.round_robin_prev_vcpu = next;
420 
421 	if (!apic)
422 		printk(KERN_DEBUG "vcpu not ready for apic_round_robin\n");
423 
424 	return apic;
425 }
426 
427 struct kvm_vcpu *kvm_get_lowest_prio_vcpu(struct kvm *kvm, u8 vector,
428 		unsigned long bitmap)
429 {
430 	struct kvm_lapic *apic;
431 
432 	apic = kvm_apic_round_robin(kvm, vector, bitmap);
433 	if (apic)
434 		return apic->vcpu;
435 	return NULL;
436 }
437 
438 static void apic_set_eoi(struct kvm_lapic *apic)
439 {
440 	int vector = apic_find_highest_isr(apic);
441 
442 	/*
443 	 * Not every write EOI will has corresponding ISR,
444 	 * one example is when Kernel check timer on setup_IO_APIC
445 	 */
446 	if (vector == -1)
447 		return;
448 
449 	apic_clear_vector(vector, apic->regs + APIC_ISR);
450 	apic_update_ppr(apic);
451 
452 	if (apic_test_and_clear_vector(vector, apic->regs + APIC_TMR))
453 		kvm_ioapic_update_eoi(apic->vcpu->kvm, vector);
454 }
455 
456 static void apic_send_ipi(struct kvm_lapic *apic)
457 {
458 	u32 icr_low = apic_get_reg(apic, APIC_ICR);
459 	u32 icr_high = apic_get_reg(apic, APIC_ICR2);
460 
461 	unsigned int dest = GET_APIC_DEST_FIELD(icr_high);
462 	unsigned int short_hand = icr_low & APIC_SHORT_MASK;
463 	unsigned int trig_mode = icr_low & APIC_INT_LEVELTRIG;
464 	unsigned int level = icr_low & APIC_INT_ASSERT;
465 	unsigned int dest_mode = icr_low & APIC_DEST_MASK;
466 	unsigned int delivery_mode = icr_low & APIC_MODE_MASK;
467 	unsigned int vector = icr_low & APIC_VECTOR_MASK;
468 
469 	struct kvm_vcpu *target;
470 	struct kvm_vcpu *vcpu;
471 	unsigned long lpr_map = 0;
472 	int i;
473 
474 	apic_debug("icr_high 0x%x, icr_low 0x%x, "
475 		   "short_hand 0x%x, dest 0x%x, trig_mode 0x%x, level 0x%x, "
476 		   "dest_mode 0x%x, delivery_mode 0x%x, vector 0x%x\n",
477 		   icr_high, icr_low, short_hand, dest,
478 		   trig_mode, level, dest_mode, delivery_mode, vector);
479 
480 	for (i = 0; i < KVM_MAX_VCPUS; i++) {
481 		vcpu = apic->vcpu->kvm->vcpus[i];
482 		if (!vcpu)
483 			continue;
484 
485 		if (vcpu->arch.apic &&
486 		    apic_match_dest(vcpu, apic, short_hand, dest, dest_mode)) {
487 			if (delivery_mode == APIC_DM_LOWEST)
488 				set_bit(vcpu->vcpu_id, &lpr_map);
489 			else
490 				__apic_accept_irq(vcpu->arch.apic, delivery_mode,
491 						  vector, level, trig_mode);
492 		}
493 	}
494 
495 	if (delivery_mode == APIC_DM_LOWEST) {
496 		target = kvm_get_lowest_prio_vcpu(vcpu->kvm, vector, lpr_map);
497 		if (target != NULL)
498 			__apic_accept_irq(target->arch.apic, delivery_mode,
499 					  vector, level, trig_mode);
500 	}
501 }
502 
503 static u32 apic_get_tmcct(struct kvm_lapic *apic)
504 {
505 	u64 counter_passed;
506 	ktime_t passed, now;
507 	u32 tmcct;
508 
509 	ASSERT(apic != NULL);
510 
511 	now = apic->timer.dev.base->get_time();
512 	tmcct = apic_get_reg(apic, APIC_TMICT);
513 
514 	/* if initial count is 0, current count should also be 0 */
515 	if (tmcct == 0)
516 		return 0;
517 
518 	if (unlikely(ktime_to_ns(now) <=
519 		ktime_to_ns(apic->timer.last_update))) {
520 		/* Wrap around */
521 		passed = ktime_add(( {
522 				    (ktime_t) {
523 				    .tv64 = KTIME_MAX -
524 				    (apic->timer.last_update).tv64}; }
525 				   ), now);
526 		apic_debug("time elapsed\n");
527 	} else
528 		passed = ktime_sub(now, apic->timer.last_update);
529 
530 	counter_passed = div64_u64(ktime_to_ns(passed),
531 				   (APIC_BUS_CYCLE_NS * apic->timer.divide_count));
532 
533 	if (counter_passed > tmcct) {
534 		if (unlikely(!apic_lvtt_period(apic))) {
535 			/* one-shot timers stick at 0 until reset */
536 			tmcct = 0;
537 		} else {
538 			/*
539 			 * periodic timers reset to APIC_TMICT when they
540 			 * hit 0. The while loop simulates this happening N
541 			 * times. (counter_passed %= tmcct) would also work,
542 			 * but might be slower or not work on 32-bit??
543 			 */
544 			while (counter_passed > tmcct)
545 				counter_passed -= tmcct;
546 			tmcct -= counter_passed;
547 		}
548 	} else {
549 		tmcct -= counter_passed;
550 	}
551 
552 	return tmcct;
553 }
554 
555 static void __report_tpr_access(struct kvm_lapic *apic, bool write)
556 {
557 	struct kvm_vcpu *vcpu = apic->vcpu;
558 	struct kvm_run *run = vcpu->run;
559 
560 	set_bit(KVM_REQ_REPORT_TPR_ACCESS, &vcpu->requests);
561 	kvm_x86_ops->cache_regs(vcpu);
562 	run->tpr_access.rip = vcpu->arch.rip;
563 	run->tpr_access.is_write = write;
564 }
565 
566 static inline void report_tpr_access(struct kvm_lapic *apic, bool write)
567 {
568 	if (apic->vcpu->arch.tpr_access_reporting)
569 		__report_tpr_access(apic, write);
570 }
571 
572 static u32 __apic_read(struct kvm_lapic *apic, unsigned int offset)
573 {
574 	u32 val = 0;
575 
576 	KVMTRACE_1D(APIC_ACCESS, apic->vcpu, (u32)offset, handler);
577 
578 	if (offset >= LAPIC_MMIO_LENGTH)
579 		return 0;
580 
581 	switch (offset) {
582 	case APIC_ARBPRI:
583 		printk(KERN_WARNING "Access APIC ARBPRI register "
584 		       "which is for P6\n");
585 		break;
586 
587 	case APIC_TMCCT:	/* Timer CCR */
588 		val = apic_get_tmcct(apic);
589 		break;
590 
591 	case APIC_TASKPRI:
592 		report_tpr_access(apic, false);
593 		/* fall thru */
594 	default:
595 		apic_update_ppr(apic);
596 		val = apic_get_reg(apic, offset);
597 		break;
598 	}
599 
600 	return val;
601 }
602 
603 static void apic_mmio_read(struct kvm_io_device *this,
604 			   gpa_t address, int len, void *data)
605 {
606 	struct kvm_lapic *apic = (struct kvm_lapic *)this->private;
607 	unsigned int offset = address - apic->base_address;
608 	unsigned char alignment = offset & 0xf;
609 	u32 result;
610 
611 	if ((alignment + len) > 4) {
612 		printk(KERN_ERR "KVM_APIC_READ: alignment error %lx %d",
613 		       (unsigned long)address, len);
614 		return;
615 	}
616 	result = __apic_read(apic, offset & ~0xf);
617 
618 	switch (len) {
619 	case 1:
620 	case 2:
621 	case 4:
622 		memcpy(data, (char *)&result + alignment, len);
623 		break;
624 	default:
625 		printk(KERN_ERR "Local APIC read with len = %x, "
626 		       "should be 1,2, or 4 instead\n", len);
627 		break;
628 	}
629 }
630 
631 static void update_divide_count(struct kvm_lapic *apic)
632 {
633 	u32 tmp1, tmp2, tdcr;
634 
635 	tdcr = apic_get_reg(apic, APIC_TDCR);
636 	tmp1 = tdcr & 0xf;
637 	tmp2 = ((tmp1 & 0x3) | ((tmp1 & 0x8) >> 1)) + 1;
638 	apic->timer.divide_count = 0x1 << (tmp2 & 0x7);
639 
640 	apic_debug("timer divide count is 0x%x\n",
641 				   apic->timer.divide_count);
642 }
643 
644 static void start_apic_timer(struct kvm_lapic *apic)
645 {
646 	ktime_t now = apic->timer.dev.base->get_time();
647 
648 	apic->timer.last_update = now;
649 
650 	apic->timer.period = apic_get_reg(apic, APIC_TMICT) *
651 		    APIC_BUS_CYCLE_NS * apic->timer.divide_count;
652 	atomic_set(&apic->timer.pending, 0);
653 
654 	if (!apic->timer.period)
655 		return;
656 
657 	hrtimer_start(&apic->timer.dev,
658 		      ktime_add_ns(now, apic->timer.period),
659 		      HRTIMER_MODE_ABS);
660 
661 	apic_debug("%s: bus cycle is %" PRId64 "ns, now 0x%016"
662 			   PRIx64 ", "
663 			   "timer initial count 0x%x, period %lldns, "
664 			   "expire @ 0x%016" PRIx64 ".\n", __func__,
665 			   APIC_BUS_CYCLE_NS, ktime_to_ns(now),
666 			   apic_get_reg(apic, APIC_TMICT),
667 			   apic->timer.period,
668 			   ktime_to_ns(ktime_add_ns(now,
669 					apic->timer.period)));
670 }
671 
672 static void apic_mmio_write(struct kvm_io_device *this,
673 			    gpa_t address, int len, const void *data)
674 {
675 	struct kvm_lapic *apic = (struct kvm_lapic *)this->private;
676 	unsigned int offset = address - apic->base_address;
677 	unsigned char alignment = offset & 0xf;
678 	u32 val;
679 
680 	/*
681 	 * APIC register must be aligned on 128-bits boundary.
682 	 * 32/64/128 bits registers must be accessed thru 32 bits.
683 	 * Refer SDM 8.4.1
684 	 */
685 	if (len != 4 || alignment) {
686 		if (printk_ratelimit())
687 			printk(KERN_ERR "apic write: bad size=%d %lx\n",
688 			       len, (long)address);
689 		return;
690 	}
691 
692 	val = *(u32 *) data;
693 
694 	/* too common printing */
695 	if (offset != APIC_EOI)
696 		apic_debug("%s: offset 0x%x with length 0x%x, and value is "
697 			   "0x%x\n", __func__, offset, len, val);
698 
699 	offset &= 0xff0;
700 
701 	KVMTRACE_1D(APIC_ACCESS, apic->vcpu, (u32)offset, handler);
702 
703 	switch (offset) {
704 	case APIC_ID:		/* Local APIC ID */
705 		apic_set_reg(apic, APIC_ID, val);
706 		break;
707 
708 	case APIC_TASKPRI:
709 		report_tpr_access(apic, true);
710 		apic_set_tpr(apic, val & 0xff);
711 		break;
712 
713 	case APIC_EOI:
714 		apic_set_eoi(apic);
715 		break;
716 
717 	case APIC_LDR:
718 		apic_set_reg(apic, APIC_LDR, val & APIC_LDR_MASK);
719 		break;
720 
721 	case APIC_DFR:
722 		apic_set_reg(apic, APIC_DFR, val | 0x0FFFFFFF);
723 		break;
724 
725 	case APIC_SPIV:
726 		apic_set_reg(apic, APIC_SPIV, val & 0x3ff);
727 		if (!(val & APIC_SPIV_APIC_ENABLED)) {
728 			int i;
729 			u32 lvt_val;
730 
731 			for (i = 0; i < APIC_LVT_NUM; i++) {
732 				lvt_val = apic_get_reg(apic,
733 						       APIC_LVTT + 0x10 * i);
734 				apic_set_reg(apic, APIC_LVTT + 0x10 * i,
735 					     lvt_val | APIC_LVT_MASKED);
736 			}
737 			atomic_set(&apic->timer.pending, 0);
738 
739 		}
740 		break;
741 
742 	case APIC_ICR:
743 		/* No delay here, so we always clear the pending bit */
744 		apic_set_reg(apic, APIC_ICR, val & ~(1 << 12));
745 		apic_send_ipi(apic);
746 		break;
747 
748 	case APIC_ICR2:
749 		apic_set_reg(apic, APIC_ICR2, val & 0xff000000);
750 		break;
751 
752 	case APIC_LVTT:
753 	case APIC_LVTTHMR:
754 	case APIC_LVTPC:
755 	case APIC_LVT0:
756 	case APIC_LVT1:
757 	case APIC_LVTERR:
758 		/* TODO: Check vector */
759 		if (!apic_sw_enabled(apic))
760 			val |= APIC_LVT_MASKED;
761 
762 		val &= apic_lvt_mask[(offset - APIC_LVTT) >> 4];
763 		apic_set_reg(apic, offset, val);
764 
765 		break;
766 
767 	case APIC_TMICT:
768 		hrtimer_cancel(&apic->timer.dev);
769 		apic_set_reg(apic, APIC_TMICT, val);
770 		start_apic_timer(apic);
771 		return;
772 
773 	case APIC_TDCR:
774 		if (val & 4)
775 			printk(KERN_ERR "KVM_WRITE:TDCR %x\n", val);
776 		apic_set_reg(apic, APIC_TDCR, val);
777 		update_divide_count(apic);
778 		break;
779 
780 	default:
781 		apic_debug("Local APIC Write to read-only register %x\n",
782 			   offset);
783 		break;
784 	}
785 
786 }
787 
788 static int apic_mmio_range(struct kvm_io_device *this, gpa_t addr,
789 			   int len, int size)
790 {
791 	struct kvm_lapic *apic = (struct kvm_lapic *)this->private;
792 	int ret = 0;
793 
794 
795 	if (apic_hw_enabled(apic) &&
796 	    (addr >= apic->base_address) &&
797 	    (addr < (apic->base_address + LAPIC_MMIO_LENGTH)))
798 		ret = 1;
799 
800 	return ret;
801 }
802 
803 void kvm_free_lapic(struct kvm_vcpu *vcpu)
804 {
805 	if (!vcpu->arch.apic)
806 		return;
807 
808 	hrtimer_cancel(&vcpu->arch.apic->timer.dev);
809 
810 	if (vcpu->arch.apic->regs_page)
811 		__free_page(vcpu->arch.apic->regs_page);
812 
813 	kfree(vcpu->arch.apic);
814 }
815 
816 /*
817  *----------------------------------------------------------------------
818  * LAPIC interface
819  *----------------------------------------------------------------------
820  */
821 
822 void kvm_lapic_set_tpr(struct kvm_vcpu *vcpu, unsigned long cr8)
823 {
824 	struct kvm_lapic *apic = vcpu->arch.apic;
825 
826 	if (!apic)
827 		return;
828 	apic_set_tpr(apic, ((cr8 & 0x0f) << 4)
829 		     | (apic_get_reg(apic, APIC_TASKPRI) & 4));
830 }
831 EXPORT_SYMBOL_GPL(kvm_lapic_set_tpr);
832 
833 u64 kvm_lapic_get_cr8(struct kvm_vcpu *vcpu)
834 {
835 	struct kvm_lapic *apic = vcpu->arch.apic;
836 	u64 tpr;
837 
838 	if (!apic)
839 		return 0;
840 	tpr = (u64) apic_get_reg(apic, APIC_TASKPRI);
841 
842 	return (tpr & 0xf0) >> 4;
843 }
844 EXPORT_SYMBOL_GPL(kvm_lapic_get_cr8);
845 
846 void kvm_lapic_set_base(struct kvm_vcpu *vcpu, u64 value)
847 {
848 	struct kvm_lapic *apic = vcpu->arch.apic;
849 
850 	if (!apic) {
851 		value |= MSR_IA32_APICBASE_BSP;
852 		vcpu->arch.apic_base = value;
853 		return;
854 	}
855 	if (apic->vcpu->vcpu_id)
856 		value &= ~MSR_IA32_APICBASE_BSP;
857 
858 	vcpu->arch.apic_base = value;
859 	apic->base_address = apic->vcpu->arch.apic_base &
860 			     MSR_IA32_APICBASE_BASE;
861 
862 	/* with FSB delivery interrupt, we can restart APIC functionality */
863 	apic_debug("apic base msr is 0x%016" PRIx64 ", and base address is "
864 		   "0x%lx.\n", apic->vcpu->arch.apic_base, apic->base_address);
865 
866 }
867 
868 u64 kvm_lapic_get_base(struct kvm_vcpu *vcpu)
869 {
870 	return vcpu->arch.apic_base;
871 }
872 EXPORT_SYMBOL_GPL(kvm_lapic_get_base);
873 
874 void kvm_lapic_reset(struct kvm_vcpu *vcpu)
875 {
876 	struct kvm_lapic *apic;
877 	int i;
878 
879 	apic_debug("%s\n", __func__);
880 
881 	ASSERT(vcpu);
882 	apic = vcpu->arch.apic;
883 	ASSERT(apic != NULL);
884 
885 	/* Stop the timer in case it's a reset to an active apic */
886 	hrtimer_cancel(&apic->timer.dev);
887 
888 	apic_set_reg(apic, APIC_ID, vcpu->vcpu_id << 24);
889 	apic_set_reg(apic, APIC_LVR, APIC_VERSION);
890 
891 	for (i = 0; i < APIC_LVT_NUM; i++)
892 		apic_set_reg(apic, APIC_LVTT + 0x10 * i, APIC_LVT_MASKED);
893 	apic_set_reg(apic, APIC_LVT0,
894 		     SET_APIC_DELIVERY_MODE(0, APIC_MODE_EXTINT));
895 
896 	apic_set_reg(apic, APIC_DFR, 0xffffffffU);
897 	apic_set_reg(apic, APIC_SPIV, 0xff);
898 	apic_set_reg(apic, APIC_TASKPRI, 0);
899 	apic_set_reg(apic, APIC_LDR, 0);
900 	apic_set_reg(apic, APIC_ESR, 0);
901 	apic_set_reg(apic, APIC_ICR, 0);
902 	apic_set_reg(apic, APIC_ICR2, 0);
903 	apic_set_reg(apic, APIC_TDCR, 0);
904 	apic_set_reg(apic, APIC_TMICT, 0);
905 	for (i = 0; i < 8; i++) {
906 		apic_set_reg(apic, APIC_IRR + 0x10 * i, 0);
907 		apic_set_reg(apic, APIC_ISR + 0x10 * i, 0);
908 		apic_set_reg(apic, APIC_TMR + 0x10 * i, 0);
909 	}
910 	update_divide_count(apic);
911 	atomic_set(&apic->timer.pending, 0);
912 	if (vcpu->vcpu_id == 0)
913 		vcpu->arch.apic_base |= MSR_IA32_APICBASE_BSP;
914 	apic_update_ppr(apic);
915 
916 	apic_debug(KERN_INFO "%s: vcpu=%p, id=%d, base_msr="
917 		   "0x%016" PRIx64 ", base_address=0x%0lx.\n", __func__,
918 		   vcpu, kvm_apic_id(apic),
919 		   vcpu->arch.apic_base, apic->base_address);
920 }
921 EXPORT_SYMBOL_GPL(kvm_lapic_reset);
922 
923 int kvm_lapic_enabled(struct kvm_vcpu *vcpu)
924 {
925 	struct kvm_lapic *apic = vcpu->arch.apic;
926 	int ret = 0;
927 
928 	if (!apic)
929 		return 0;
930 	ret = apic_enabled(apic);
931 
932 	return ret;
933 }
934 EXPORT_SYMBOL_GPL(kvm_lapic_enabled);
935 
936 /*
937  *----------------------------------------------------------------------
938  * timer interface
939  *----------------------------------------------------------------------
940  */
941 
942 /* TODO: make sure __apic_timer_fn runs in current pCPU */
943 static int __apic_timer_fn(struct kvm_lapic *apic)
944 {
945 	int result = 0;
946 	wait_queue_head_t *q = &apic->vcpu->wq;
947 
948 	if(!atomic_inc_and_test(&apic->timer.pending))
949 		set_bit(KVM_REQ_PENDING_TIMER, &apic->vcpu->requests);
950 	if (waitqueue_active(q)) {
951 		apic->vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE;
952 		wake_up_interruptible(q);
953 	}
954 	if (apic_lvtt_period(apic)) {
955 		result = 1;
956 		apic->timer.dev.expires = ktime_add_ns(
957 					apic->timer.dev.expires,
958 					apic->timer.period);
959 	}
960 	return result;
961 }
962 
963 int apic_has_pending_timer(struct kvm_vcpu *vcpu)
964 {
965 	struct kvm_lapic *lapic = vcpu->arch.apic;
966 
967 	if (lapic && apic_enabled(lapic) && apic_lvt_enabled(lapic, APIC_LVTT))
968 		return atomic_read(&lapic->timer.pending);
969 
970 	return 0;
971 }
972 
973 static int __inject_apic_timer_irq(struct kvm_lapic *apic)
974 {
975 	int vector;
976 
977 	vector = apic_lvt_vector(apic, APIC_LVTT);
978 	return __apic_accept_irq(apic, APIC_DM_FIXED, vector, 1, 0);
979 }
980 
981 static enum hrtimer_restart apic_timer_fn(struct hrtimer *data)
982 {
983 	struct kvm_lapic *apic;
984 	int restart_timer = 0;
985 
986 	apic = container_of(data, struct kvm_lapic, timer.dev);
987 
988 	restart_timer = __apic_timer_fn(apic);
989 
990 	if (restart_timer)
991 		return HRTIMER_RESTART;
992 	else
993 		return HRTIMER_NORESTART;
994 }
995 
996 int kvm_create_lapic(struct kvm_vcpu *vcpu)
997 {
998 	struct kvm_lapic *apic;
999 
1000 	ASSERT(vcpu != NULL);
1001 	apic_debug("apic_init %d\n", vcpu->vcpu_id);
1002 
1003 	apic = kzalloc(sizeof(*apic), GFP_KERNEL);
1004 	if (!apic)
1005 		goto nomem;
1006 
1007 	vcpu->arch.apic = apic;
1008 
1009 	apic->regs_page = alloc_page(GFP_KERNEL);
1010 	if (apic->regs_page == NULL) {
1011 		printk(KERN_ERR "malloc apic regs error for vcpu %x\n",
1012 		       vcpu->vcpu_id);
1013 		goto nomem_free_apic;
1014 	}
1015 	apic->regs = page_address(apic->regs_page);
1016 	memset(apic->regs, 0, PAGE_SIZE);
1017 	apic->vcpu = vcpu;
1018 
1019 	hrtimer_init(&apic->timer.dev, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
1020 	apic->timer.dev.function = apic_timer_fn;
1021 	apic->base_address = APIC_DEFAULT_PHYS_BASE;
1022 	vcpu->arch.apic_base = APIC_DEFAULT_PHYS_BASE;
1023 
1024 	kvm_lapic_reset(vcpu);
1025 	apic->dev.read = apic_mmio_read;
1026 	apic->dev.write = apic_mmio_write;
1027 	apic->dev.in_range = apic_mmio_range;
1028 	apic->dev.private = apic;
1029 
1030 	return 0;
1031 nomem_free_apic:
1032 	kfree(apic);
1033 nomem:
1034 	return -ENOMEM;
1035 }
1036 EXPORT_SYMBOL_GPL(kvm_create_lapic);
1037 
1038 int kvm_apic_has_interrupt(struct kvm_vcpu *vcpu)
1039 {
1040 	struct kvm_lapic *apic = vcpu->arch.apic;
1041 	int highest_irr;
1042 
1043 	if (!apic || !apic_enabled(apic))
1044 		return -1;
1045 
1046 	apic_update_ppr(apic);
1047 	highest_irr = apic_find_highest_irr(apic);
1048 	if ((highest_irr == -1) ||
1049 	    ((highest_irr & 0xF0) <= apic_get_reg(apic, APIC_PROCPRI)))
1050 		return -1;
1051 	return highest_irr;
1052 }
1053 
1054 int kvm_apic_accept_pic_intr(struct kvm_vcpu *vcpu)
1055 {
1056 	u32 lvt0 = apic_get_reg(vcpu->arch.apic, APIC_LVT0);
1057 	int r = 0;
1058 
1059 	if (vcpu->vcpu_id == 0) {
1060 		if (!apic_hw_enabled(vcpu->arch.apic))
1061 			r = 1;
1062 		if ((lvt0 & APIC_LVT_MASKED) == 0 &&
1063 		    GET_APIC_DELIVERY_MODE(lvt0) == APIC_MODE_EXTINT)
1064 			r = 1;
1065 	}
1066 	return r;
1067 }
1068 
1069 void kvm_inject_apic_timer_irqs(struct kvm_vcpu *vcpu)
1070 {
1071 	struct kvm_lapic *apic = vcpu->arch.apic;
1072 
1073 	if (apic && apic_lvt_enabled(apic, APIC_LVTT) &&
1074 		atomic_read(&apic->timer.pending) > 0) {
1075 		if (__inject_apic_timer_irq(apic))
1076 			atomic_dec(&apic->timer.pending);
1077 	}
1078 }
1079 
1080 void kvm_apic_timer_intr_post(struct kvm_vcpu *vcpu, int vec)
1081 {
1082 	struct kvm_lapic *apic = vcpu->arch.apic;
1083 
1084 	if (apic && apic_lvt_vector(apic, APIC_LVTT) == vec)
1085 		apic->timer.last_update = ktime_add_ns(
1086 				apic->timer.last_update,
1087 				apic->timer.period);
1088 }
1089 
1090 int kvm_get_apic_interrupt(struct kvm_vcpu *vcpu)
1091 {
1092 	int vector = kvm_apic_has_interrupt(vcpu);
1093 	struct kvm_lapic *apic = vcpu->arch.apic;
1094 
1095 	if (vector == -1)
1096 		return -1;
1097 
1098 	apic_set_vector(vector, apic->regs + APIC_ISR);
1099 	apic_update_ppr(apic);
1100 	apic_clear_irr(vector, apic);
1101 	return vector;
1102 }
1103 
1104 void kvm_apic_post_state_restore(struct kvm_vcpu *vcpu)
1105 {
1106 	struct kvm_lapic *apic = vcpu->arch.apic;
1107 
1108 	apic->base_address = vcpu->arch.apic_base &
1109 			     MSR_IA32_APICBASE_BASE;
1110 	apic_set_reg(apic, APIC_LVR, APIC_VERSION);
1111 	apic_update_ppr(apic);
1112 	hrtimer_cancel(&apic->timer.dev);
1113 	update_divide_count(apic);
1114 	start_apic_timer(apic);
1115 }
1116 
1117 void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu)
1118 {
1119 	struct kvm_lapic *apic = vcpu->arch.apic;
1120 	struct hrtimer *timer;
1121 
1122 	if (!apic)
1123 		return;
1124 
1125 	timer = &apic->timer.dev;
1126 	if (hrtimer_cancel(timer))
1127 		hrtimer_start(timer, timer->expires, HRTIMER_MODE_ABS);
1128 }
1129 
1130 void kvm_lapic_sync_from_vapic(struct kvm_vcpu *vcpu)
1131 {
1132 	u32 data;
1133 	void *vapic;
1134 
1135 	if (!irqchip_in_kernel(vcpu->kvm) || !vcpu->arch.apic->vapic_addr)
1136 		return;
1137 
1138 	vapic = kmap_atomic(vcpu->arch.apic->vapic_page, KM_USER0);
1139 	data = *(u32 *)(vapic + offset_in_page(vcpu->arch.apic->vapic_addr));
1140 	kunmap_atomic(vapic, KM_USER0);
1141 
1142 	apic_set_tpr(vcpu->arch.apic, data & 0xff);
1143 }
1144 
1145 void kvm_lapic_sync_to_vapic(struct kvm_vcpu *vcpu)
1146 {
1147 	u32 data, tpr;
1148 	int max_irr, max_isr;
1149 	struct kvm_lapic *apic;
1150 	void *vapic;
1151 
1152 	if (!irqchip_in_kernel(vcpu->kvm) || !vcpu->arch.apic->vapic_addr)
1153 		return;
1154 
1155 	apic = vcpu->arch.apic;
1156 	tpr = apic_get_reg(apic, APIC_TASKPRI) & 0xff;
1157 	max_irr = apic_find_highest_irr(apic);
1158 	if (max_irr < 0)
1159 		max_irr = 0;
1160 	max_isr = apic_find_highest_isr(apic);
1161 	if (max_isr < 0)
1162 		max_isr = 0;
1163 	data = (tpr & 0xff) | ((max_isr & 0xf0) << 8) | (max_irr << 24);
1164 
1165 	vapic = kmap_atomic(vcpu->arch.apic->vapic_page, KM_USER0);
1166 	*(u32 *)(vapic + offset_in_page(vcpu->arch.apic->vapic_addr)) = data;
1167 	kunmap_atomic(vapic, KM_USER0);
1168 }
1169 
1170 void kvm_lapic_set_vapic_addr(struct kvm_vcpu *vcpu, gpa_t vapic_addr)
1171 {
1172 	if (!irqchip_in_kernel(vcpu->kvm))
1173 		return;
1174 
1175 	vcpu->arch.apic->vapic_addr = vapic_addr;
1176 }
1177