2 * Copyright (C) 2001 MandrakeSoft S.A.
3 * Copyright 2010 Red Hat, Inc. and/or its affiliates.
8 * http://www.linux-mandrake.com/
9 * http://www.mandrakesoft.com/
11 * This library is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU Lesser General Public
13 * License as published by the Free Software Foundation; either
14 * version 2 of the License, or (at your option) any later version.
16 * This library is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
19 * Lesser General Public License for more details.
21 * You should have received a copy of the GNU Lesser General Public
22 * License along with this library; if not, write to the Free Software
23 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
25 * Yunhong Jiang <yunhong.jiang@intel.com>
26 * Yaozu (Eddie) Dong <eddie.dong@intel.com>
27 * Based on Xen 3.1 code.
30 #include <linux/kvm_host.h>
31 #include <linux/kvm.h>
33 #include <linux/highmem.h>
34 #include <linux/smp.h>
35 #include <linux/hrtimer.h>
37 #include <linux/slab.h>
38 #include <linux/export.h>
39 #include <asm/processor.h>
41 #include <asm/current.h>
42 #include <trace/events/kvm.h>
49 #define ioapic_debug(fmt,arg...) printk(KERN_WARNING fmt,##arg)
51 #define ioapic_debug(fmt, arg...)
53 static int ioapic_service(struct kvm_ioapic
*vioapic
, int irq
,
56 static unsigned long ioapic_read_indirect(struct kvm_ioapic
*ioapic
,
60 unsigned long result
= 0;
62 switch (ioapic
->ioregsel
) {
63 case IOAPIC_REG_VERSION
:
64 result
= ((((IOAPIC_NUM_PINS
- 1) & 0xff) << 16)
65 | (IOAPIC_VERSION_ID
& 0xff));
68 case IOAPIC_REG_APIC_ID
:
69 case IOAPIC_REG_ARB_ID
:
70 result
= ((ioapic
->id
& 0xf) << 24);
75 u32 redir_index
= (ioapic
->ioregsel
- 0x10) >> 1;
78 if (redir_index
< IOAPIC_NUM_PINS
)
80 ioapic
->redirtbl
[redir_index
].bits
;
82 redir_content
= ~0ULL;
84 result
= (ioapic
->ioregsel
& 0x1) ?
85 (redir_content
>> 32) & 0xffffffff :
86 redir_content
& 0xffffffff;
94 static void rtc_irq_eoi_tracking_reset(struct kvm_ioapic
*ioapic
)
96 ioapic
->rtc_status
.pending_eoi
= 0;
97 bitmap_zero(ioapic
->rtc_status
.dest_map
.map
, KVM_MAX_VCPU_ID
);
100 static void kvm_rtc_eoi_tracking_restore_all(struct kvm_ioapic
*ioapic
);
102 static void rtc_status_pending_eoi_check_valid(struct kvm_ioapic
*ioapic
)
104 if (WARN_ON(ioapic
->rtc_status
.pending_eoi
< 0))
105 kvm_rtc_eoi_tracking_restore_all(ioapic
);
108 static void __rtc_irq_eoi_tracking_restore_one(struct kvm_vcpu
*vcpu
)
110 bool new_val
, old_val
;
111 struct kvm_ioapic
*ioapic
= vcpu
->kvm
->arch
.vioapic
;
112 struct dest_map
*dest_map
= &ioapic
->rtc_status
.dest_map
;
113 union kvm_ioapic_redirect_entry
*e
;
115 e
= &ioapic
->redirtbl
[RTC_GSI
];
116 if (!kvm_apic_match_dest(vcpu
, NULL
, 0, e
->fields
.dest_id
,
117 e
->fields
.dest_mode
))
120 new_val
= kvm_apic_pending_eoi(vcpu
, e
->fields
.vector
);
121 old_val
= test_bit(vcpu
->vcpu_id
, dest_map
->map
);
123 if (new_val
== old_val
)
127 __set_bit(vcpu
->vcpu_id
, dest_map
->map
);
128 dest_map
->vectors
[vcpu
->vcpu_id
] = e
->fields
.vector
;
129 ioapic
->rtc_status
.pending_eoi
++;
131 __clear_bit(vcpu
->vcpu_id
, dest_map
->map
);
132 ioapic
->rtc_status
.pending_eoi
--;
133 rtc_status_pending_eoi_check_valid(ioapic
);
137 void kvm_rtc_eoi_tracking_restore_one(struct kvm_vcpu
*vcpu
)
139 struct kvm_ioapic
*ioapic
= vcpu
->kvm
->arch
.vioapic
;
141 spin_lock(&ioapic
->lock
);
142 __rtc_irq_eoi_tracking_restore_one(vcpu
);
143 spin_unlock(&ioapic
->lock
);
146 static void kvm_rtc_eoi_tracking_restore_all(struct kvm_ioapic
*ioapic
)
148 struct kvm_vcpu
*vcpu
;
151 if (RTC_GSI
>= IOAPIC_NUM_PINS
)
154 rtc_irq_eoi_tracking_reset(ioapic
);
155 kvm_for_each_vcpu(i
, vcpu
, ioapic
->kvm
)
156 __rtc_irq_eoi_tracking_restore_one(vcpu
);
159 static void rtc_irq_eoi(struct kvm_ioapic
*ioapic
, struct kvm_vcpu
*vcpu
)
161 if (test_and_clear_bit(vcpu
->vcpu_id
,
162 ioapic
->rtc_status
.dest_map
.map
)) {
163 --ioapic
->rtc_status
.pending_eoi
;
164 rtc_status_pending_eoi_check_valid(ioapic
);
168 static bool rtc_irq_check_coalesced(struct kvm_ioapic
*ioapic
)
170 if (ioapic
->rtc_status
.pending_eoi
> 0)
171 return true; /* coalesced */
176 static int ioapic_set_irq(struct kvm_ioapic
*ioapic
, unsigned int irq
,
177 int irq_level
, bool line_status
)
179 union kvm_ioapic_redirect_entry entry
;
184 entry
= ioapic
->redirtbl
[irq
];
185 edge
= (entry
.fields
.trig_mode
== IOAPIC_EDGE_TRIG
);
188 ioapic
->irr
&= ~mask
;
194 * Return 0 for coalesced interrupts; for edge-triggered interrupts,
195 * this only happens if a previous edge has not been delivered due
196 * do masking. For level interrupts, the remote_irr field tells
197 * us if the interrupt is waiting for an EOI.
199 * RTC is special: it is edge-triggered, but userspace likes to know
200 * if it has been already ack-ed via EOI because coalesced RTC
201 * interrupts lead to time drift in Windows guests. So we track
202 * EOI manually for the RTC interrupt.
204 if (irq
== RTC_GSI
&& line_status
&&
205 rtc_irq_check_coalesced(ioapic
)) {
210 old_irr
= ioapic
->irr
;
213 ioapic
->irr_delivered
&= ~mask
;
214 if ((edge
&& old_irr
== ioapic
->irr
) ||
215 (!edge
&& entry
.fields
.remote_irr
)) {
220 ret
= ioapic_service(ioapic
, irq
, line_status
);
223 trace_kvm_ioapic_set_irq(entry
.bits
, irq
, ret
== 0);
227 static void kvm_ioapic_inject_all(struct kvm_ioapic
*ioapic
, unsigned long irr
)
231 rtc_irq_eoi_tracking_reset(ioapic
);
232 for_each_set_bit(idx
, &irr
, IOAPIC_NUM_PINS
)
233 ioapic_set_irq(ioapic
, idx
, 1, true);
235 kvm_rtc_eoi_tracking_restore_all(ioapic
);
239 void kvm_ioapic_scan_entry(struct kvm_vcpu
*vcpu
, ulong
*ioapic_handled_vectors
)
241 struct kvm_ioapic
*ioapic
= vcpu
->kvm
->arch
.vioapic
;
242 struct dest_map
*dest_map
= &ioapic
->rtc_status
.dest_map
;
243 union kvm_ioapic_redirect_entry
*e
;
246 spin_lock(&ioapic
->lock
);
248 /* Make sure we see any missing RTC EOI */
249 if (test_bit(vcpu
->vcpu_id
, dest_map
->map
))
250 __set_bit(dest_map
->vectors
[vcpu
->vcpu_id
],
251 ioapic_handled_vectors
);
253 for (index
= 0; index
< IOAPIC_NUM_PINS
; index
++) {
254 e
= &ioapic
->redirtbl
[index
];
255 if (e
->fields
.trig_mode
== IOAPIC_LEVEL_TRIG
||
256 kvm_irq_has_notifier(ioapic
->kvm
, KVM_IRQCHIP_IOAPIC
, index
) ||
258 if (kvm_apic_match_dest(vcpu
, NULL
, 0,
259 e
->fields
.dest_id
, e
->fields
.dest_mode
) ||
260 (e
->fields
.trig_mode
== IOAPIC_EDGE_TRIG
&&
261 kvm_apic_pending_eoi(vcpu
, e
->fields
.vector
)))
262 __set_bit(e
->fields
.vector
,
263 ioapic_handled_vectors
);
266 spin_unlock(&ioapic
->lock
);
269 void kvm_vcpu_request_scan_ioapic(struct kvm
*kvm
)
271 struct kvm_ioapic
*ioapic
= kvm
->arch
.vioapic
;
275 kvm_make_scan_ioapic_request(kvm
);
278 static void ioapic_write_indirect(struct kvm_ioapic
*ioapic
, u32 val
)
281 bool mask_before
, mask_after
;
282 union kvm_ioapic_redirect_entry
*e
;
284 switch (ioapic
->ioregsel
) {
285 case IOAPIC_REG_VERSION
:
286 /* Writes are ignored. */
289 case IOAPIC_REG_APIC_ID
:
290 ioapic
->id
= (val
>> 24) & 0xf;
293 case IOAPIC_REG_ARB_ID
:
297 index
= (ioapic
->ioregsel
- 0x10) >> 1;
299 ioapic_debug("change redir index %x val %x\n", index
, val
);
300 if (index
>= IOAPIC_NUM_PINS
)
302 e
= &ioapic
->redirtbl
[index
];
303 mask_before
= e
->fields
.mask
;
304 if (ioapic
->ioregsel
& 1) {
305 e
->bits
&= 0xffffffff;
306 e
->bits
|= (u64
) val
<< 32;
308 e
->bits
&= ~0xffffffffULL
;
309 e
->bits
|= (u32
) val
;
310 e
->fields
.remote_irr
= 0;
312 mask_after
= e
->fields
.mask
;
313 if (mask_before
!= mask_after
)
314 kvm_fire_mask_notifiers(ioapic
->kvm
, KVM_IRQCHIP_IOAPIC
, index
, mask_after
);
315 if (e
->fields
.trig_mode
== IOAPIC_LEVEL_TRIG
316 && ioapic
->irr
& (1 << index
))
317 ioapic_service(ioapic
, index
, false);
318 kvm_vcpu_request_scan_ioapic(ioapic
->kvm
);
323 static int ioapic_service(struct kvm_ioapic
*ioapic
, int irq
, bool line_status
)
325 union kvm_ioapic_redirect_entry
*entry
= &ioapic
->redirtbl
[irq
];
326 struct kvm_lapic_irq irqe
;
329 if (entry
->fields
.mask
)
332 ioapic_debug("dest=%x dest_mode=%x delivery_mode=%x "
333 "vector=%x trig_mode=%x\n",
334 entry
->fields
.dest_id
, entry
->fields
.dest_mode
,
335 entry
->fields
.delivery_mode
, entry
->fields
.vector
,
336 entry
->fields
.trig_mode
);
338 irqe
.dest_id
= entry
->fields
.dest_id
;
339 irqe
.vector
= entry
->fields
.vector
;
340 irqe
.dest_mode
= entry
->fields
.dest_mode
;
341 irqe
.trig_mode
= entry
->fields
.trig_mode
;
342 irqe
.delivery_mode
= entry
->fields
.delivery_mode
<< 8;
345 irqe
.msi_redir_hint
= false;
347 if (irqe
.trig_mode
== IOAPIC_EDGE_TRIG
)
348 ioapic
->irr_delivered
|= 1 << irq
;
350 if (irq
== RTC_GSI
&& line_status
) {
352 * pending_eoi cannot ever become negative (see
353 * rtc_status_pending_eoi_check_valid) and the caller
354 * ensures that it is only called if it is >= zero, namely
355 * if rtc_irq_check_coalesced returns false).
357 BUG_ON(ioapic
->rtc_status
.pending_eoi
!= 0);
358 ret
= kvm_irq_delivery_to_apic(ioapic
->kvm
, NULL
, &irqe
,
359 &ioapic
->rtc_status
.dest_map
);
360 ioapic
->rtc_status
.pending_eoi
= (ret
< 0 ? 0 : ret
);
362 ret
= kvm_irq_delivery_to_apic(ioapic
->kvm
, NULL
, &irqe
, NULL
);
364 if (ret
&& irqe
.trig_mode
== IOAPIC_LEVEL_TRIG
)
365 entry
->fields
.remote_irr
= 1;
370 int kvm_ioapic_set_irq(struct kvm_ioapic
*ioapic
, int irq
, int irq_source_id
,
371 int level
, bool line_status
)
375 BUG_ON(irq
< 0 || irq
>= IOAPIC_NUM_PINS
);
377 spin_lock(&ioapic
->lock
);
378 irq_level
= __kvm_irq_line_state(&ioapic
->irq_states
[irq
],
379 irq_source_id
, level
);
380 ret
= ioapic_set_irq(ioapic
, irq
, irq_level
, line_status
);
382 spin_unlock(&ioapic
->lock
);
387 void kvm_ioapic_clear_all(struct kvm_ioapic
*ioapic
, int irq_source_id
)
391 spin_lock(&ioapic
->lock
);
392 for (i
= 0; i
< KVM_IOAPIC_NUM_PINS
; i
++)
393 __clear_bit(irq_source_id
, &ioapic
->irq_states
[i
]);
394 spin_unlock(&ioapic
->lock
);
397 static void kvm_ioapic_eoi_inject_work(struct work_struct
*work
)
400 struct kvm_ioapic
*ioapic
= container_of(work
, struct kvm_ioapic
,
402 spin_lock(&ioapic
->lock
);
403 for (i
= 0; i
< IOAPIC_NUM_PINS
; i
++) {
404 union kvm_ioapic_redirect_entry
*ent
= &ioapic
->redirtbl
[i
];
406 if (ent
->fields
.trig_mode
!= IOAPIC_LEVEL_TRIG
)
409 if (ioapic
->irr
& (1 << i
) && !ent
->fields
.remote_irr
)
410 ioapic_service(ioapic
, i
, false);
412 spin_unlock(&ioapic
->lock
);
415 #define IOAPIC_SUCCESSIVE_IRQ_MAX_COUNT 10000
417 static void __kvm_ioapic_update_eoi(struct kvm_vcpu
*vcpu
,
418 struct kvm_ioapic
*ioapic
, int vector
, int trigger_mode
)
420 struct dest_map
*dest_map
= &ioapic
->rtc_status
.dest_map
;
421 struct kvm_lapic
*apic
= vcpu
->arch
.apic
;
424 /* RTC special handling */
425 if (test_bit(vcpu
->vcpu_id
, dest_map
->map
) &&
426 vector
== dest_map
->vectors
[vcpu
->vcpu_id
])
427 rtc_irq_eoi(ioapic
, vcpu
);
429 for (i
= 0; i
< IOAPIC_NUM_PINS
; i
++) {
430 union kvm_ioapic_redirect_entry
*ent
= &ioapic
->redirtbl
[i
];
432 if (ent
->fields
.vector
!= vector
)
436 * We are dropping lock while calling ack notifiers because ack
437 * notifier callbacks for assigned devices call into IOAPIC
438 * recursively. Since remote_irr is cleared only after call
439 * to notifiers if the same vector will be delivered while lock
440 * is dropped it will be put into irr and will be delivered
441 * after ack notifier returns.
443 spin_unlock(&ioapic
->lock
);
444 kvm_notify_acked_irq(ioapic
->kvm
, KVM_IRQCHIP_IOAPIC
, i
);
445 spin_lock(&ioapic
->lock
);
447 if (trigger_mode
!= IOAPIC_LEVEL_TRIG
||
448 kvm_lapic_get_reg(apic
, APIC_SPIV
) & APIC_SPIV_DIRECTED_EOI
)
451 ASSERT(ent
->fields
.trig_mode
== IOAPIC_LEVEL_TRIG
);
452 ent
->fields
.remote_irr
= 0;
453 if (!ent
->fields
.mask
&& (ioapic
->irr
& (1 << i
))) {
454 ++ioapic
->irq_eoi
[i
];
455 if (ioapic
->irq_eoi
[i
] == IOAPIC_SUCCESSIVE_IRQ_MAX_COUNT
) {
457 * Real hardware does not deliver the interrupt
458 * immediately during eoi broadcast, and this
459 * lets a buggy guest make slow progress
460 * even if it does not correctly handle a
461 * level-triggered interrupt. Emulate this
462 * behavior if we detect an interrupt storm.
464 schedule_delayed_work(&ioapic
->eoi_inject
, HZ
/ 100);
465 ioapic
->irq_eoi
[i
] = 0;
466 trace_kvm_ioapic_delayed_eoi_inj(ent
->bits
);
468 ioapic_service(ioapic
, i
, false);
471 ioapic
->irq_eoi
[i
] = 0;
476 void kvm_ioapic_update_eoi(struct kvm_vcpu
*vcpu
, int vector
, int trigger_mode
)
478 struct kvm_ioapic
*ioapic
= vcpu
->kvm
->arch
.vioapic
;
480 spin_lock(&ioapic
->lock
);
481 __kvm_ioapic_update_eoi(vcpu
, ioapic
, vector
, trigger_mode
);
482 spin_unlock(&ioapic
->lock
);
485 static inline struct kvm_ioapic
*to_ioapic(struct kvm_io_device
*dev
)
487 return container_of(dev
, struct kvm_ioapic
, dev
);
490 static inline int ioapic_in_range(struct kvm_ioapic
*ioapic
, gpa_t addr
)
492 return ((addr
>= ioapic
->base_address
&&
493 (addr
< ioapic
->base_address
+ IOAPIC_MEM_LENGTH
)));
496 static int ioapic_mmio_read(struct kvm_vcpu
*vcpu
, struct kvm_io_device
*this,
497 gpa_t addr
, int len
, void *val
)
499 struct kvm_ioapic
*ioapic
= to_ioapic(this);
501 if (!ioapic_in_range(ioapic
, addr
))
504 ioapic_debug("addr %lx\n", (unsigned long)addr
);
505 ASSERT(!(addr
& 0xf)); /* check alignment */
508 spin_lock(&ioapic
->lock
);
510 case IOAPIC_REG_SELECT
:
511 result
= ioapic
->ioregsel
;
514 case IOAPIC_REG_WINDOW
:
515 result
= ioapic_read_indirect(ioapic
, addr
, len
);
522 spin_unlock(&ioapic
->lock
);
526 *(u64
*) val
= result
;
531 memcpy(val
, (char *)&result
, len
);
534 printk(KERN_WARNING
"ioapic: wrong length %d\n", len
);
539 static int ioapic_mmio_write(struct kvm_vcpu
*vcpu
, struct kvm_io_device
*this,
540 gpa_t addr
, int len
, const void *val
)
542 struct kvm_ioapic
*ioapic
= to_ioapic(this);
544 if (!ioapic_in_range(ioapic
, addr
))
547 ioapic_debug("ioapic_mmio_write addr=%p len=%d val=%p\n",
548 (void*)addr
, len
, val
);
549 ASSERT(!(addr
& 0xf)); /* check alignment */
563 printk(KERN_WARNING
"ioapic: Unsupported size %d\n", len
);
568 spin_lock(&ioapic
->lock
);
570 case IOAPIC_REG_SELECT
:
571 ioapic
->ioregsel
= data
& 0xFF; /* 8-bit register */
574 case IOAPIC_REG_WINDOW
:
575 ioapic_write_indirect(ioapic
, data
);
581 spin_unlock(&ioapic
->lock
);
585 static void kvm_ioapic_reset(struct kvm_ioapic
*ioapic
)
589 cancel_delayed_work_sync(&ioapic
->eoi_inject
);
590 for (i
= 0; i
< IOAPIC_NUM_PINS
; i
++)
591 ioapic
->redirtbl
[i
].fields
.mask
= 1;
592 ioapic
->base_address
= IOAPIC_DEFAULT_BASE_ADDRESS
;
593 ioapic
->ioregsel
= 0;
595 ioapic
->irr_delivered
= 0;
597 memset(ioapic
->irq_eoi
, 0x00, sizeof(ioapic
->irq_eoi
));
598 rtc_irq_eoi_tracking_reset(ioapic
);
601 static const struct kvm_io_device_ops ioapic_mmio_ops
= {
602 .read
= ioapic_mmio_read
,
603 .write
= ioapic_mmio_write
,
606 int kvm_ioapic_init(struct kvm
*kvm
)
608 struct kvm_ioapic
*ioapic
;
611 ioapic
= kzalloc(sizeof(struct kvm_ioapic
), GFP_KERNEL
);
614 spin_lock_init(&ioapic
->lock
);
615 INIT_DELAYED_WORK(&ioapic
->eoi_inject
, kvm_ioapic_eoi_inject_work
);
616 kvm
->arch
.vioapic
= ioapic
;
617 kvm_ioapic_reset(ioapic
);
618 kvm_iodevice_init(&ioapic
->dev
, &ioapic_mmio_ops
);
620 mutex_lock(&kvm
->slots_lock
);
621 ret
= kvm_io_bus_register_dev(kvm
, KVM_MMIO_BUS
, ioapic
->base_address
,
622 IOAPIC_MEM_LENGTH
, &ioapic
->dev
);
623 mutex_unlock(&kvm
->slots_lock
);
625 kvm
->arch
.vioapic
= NULL
;
630 kvm_vcpu_request_scan_ioapic(kvm
);
634 void kvm_ioapic_destroy(struct kvm
*kvm
)
636 struct kvm_ioapic
*ioapic
= kvm
->arch
.vioapic
;
641 cancel_delayed_work_sync(&ioapic
->eoi_inject
);
642 kvm_io_bus_unregister_dev(kvm
, KVM_MMIO_BUS
, &ioapic
->dev
);
643 kvm
->arch
.vioapic
= NULL
;
647 int kvm_get_ioapic(struct kvm
*kvm
, struct kvm_ioapic_state
*state
)
649 struct kvm_ioapic
*ioapic
= ioapic_irqchip(kvm
);
653 spin_lock(&ioapic
->lock
);
654 memcpy(state
, ioapic
, sizeof(struct kvm_ioapic_state
));
655 state
->irr
&= ~ioapic
->irr_delivered
;
656 spin_unlock(&ioapic
->lock
);
660 int kvm_set_ioapic(struct kvm
*kvm
, struct kvm_ioapic_state
*state
)
662 struct kvm_ioapic
*ioapic
= ioapic_irqchip(kvm
);
666 spin_lock(&ioapic
->lock
);
667 memcpy(ioapic
, state
, sizeof(struct kvm_ioapic_state
));
669 ioapic
->irr_delivered
= 0;
670 kvm_vcpu_request_scan_ioapic(kvm
);
671 kvm_ioapic_inject_all(ioapic
, state
->irr
);
672 spin_unlock(&ioapic
->lock
);