2 * irq_comm.c: Common API for in kernel interrupt controller
3 * Copyright (c) 2007, Intel Corporation.
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms and conditions of the GNU General Public License,
7 * version 2, as published by the Free Software Foundation.
9 * This program is distributed in the hope it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
14 * You should have received a copy of the GNU General Public License along with
15 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
16 * Place - Suite 330, Boston, MA 02111-1307 USA.
18 * Yaozu (Eddie) Dong <Eddie.dong@intel.com>
20 * Copyright 2010 Red Hat, Inc. and/or its affiliates.
23 #include <linux/kvm_host.h>
24 #include <linux/slab.h>
25 #include <linux/export.h>
26 #include <trace/events/kvm.h>
28 #include <asm/msidef.h>
30 #include <asm/iosapic.h>
37 static int kvm_set_pic_irq(struct kvm_kernel_irq_routing_entry *e,
38 struct kvm *kvm, int irq_source_id, int level)
41 struct kvm_pic *pic = pic_irqchip(kvm);
42 return kvm_pic_set_irq(pic, e->irqchip.pin, irq_source_id, level);
48 static int kvm_set_ioapic_irq(struct kvm_kernel_irq_routing_entry *e,
49 struct kvm *kvm, int irq_source_id, int level)
51 struct kvm_ioapic *ioapic = kvm->arch.vioapic;
52 return kvm_ioapic_set_irq(ioapic, e->irqchip.pin, irq_source_id, level);
55 inline static bool kvm_is_dm_lowest_prio(struct kvm_lapic_irq *irq)
58 return irq->delivery_mode ==
59 (IOSAPIC_LOWEST_PRIORITY << IOSAPIC_DELIVERY_SHIFT);
61 return irq->delivery_mode == APIC_DM_LOWEST;
65 int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src,
66 struct kvm_lapic_irq *irq)
69 struct kvm_vcpu *vcpu, *lowest = NULL;
71 if (irq->dest_mode == 0 && irq->dest_id == 0xff &&
72 kvm_is_dm_lowest_prio(irq)) {
73 printk(KERN_INFO "kvm: apic: phys broadcast and lowest prio\n");
74 irq->delivery_mode = APIC_DM_FIXED;
77 if (kvm_irq_delivery_to_apic_fast(kvm, src, irq, &r))
80 kvm_for_each_vcpu(i, vcpu, kvm) {
81 if (!kvm_apic_present(vcpu))
84 if (!kvm_apic_match_dest(vcpu, src, irq->shorthand,
85 irq->dest_id, irq->dest_mode))
88 if (!kvm_is_dm_lowest_prio(irq)) {
91 r += kvm_apic_set_irq(vcpu, irq);
92 } else if (kvm_lapic_enabled(vcpu)) {
95 else if (kvm_apic_compare_prio(vcpu, lowest) < 0)
101 r = kvm_apic_set_irq(lowest, irq);
106 static inline void kvm_set_msi_irq(struct kvm_kernel_irq_routing_entry *e,
107 struct kvm_lapic_irq *irq)
109 trace_kvm_msi_set_irq(e->msi.address_lo, e->msi.data);
111 irq->dest_id = (e->msi.address_lo &
112 MSI_ADDR_DEST_ID_MASK) >> MSI_ADDR_DEST_ID_SHIFT;
113 irq->vector = (e->msi.data &
114 MSI_DATA_VECTOR_MASK) >> MSI_DATA_VECTOR_SHIFT;
115 irq->dest_mode = (1 << MSI_ADDR_DEST_MODE_SHIFT) & e->msi.address_lo;
116 irq->trig_mode = (1 << MSI_DATA_TRIGGER_SHIFT) & e->msi.data;
117 irq->delivery_mode = e->msi.data & 0x700;
120 /* TODO Deal with RH bit of MSI message address */
123 int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
124 struct kvm *kvm, int irq_source_id, int level)
126 struct kvm_lapic_irq irq;
131 kvm_set_msi_irq(e, &irq);
133 return kvm_irq_delivery_to_apic(kvm, NULL, &irq);
137 static int kvm_set_msi_inatomic(struct kvm_kernel_irq_routing_entry *e,
140 struct kvm_lapic_irq irq;
143 kvm_set_msi_irq(e, &irq);
145 if (kvm_irq_delivery_to_apic_fast(kvm, NULL, &irq, &r))
151 int kvm_send_userspace_msi(struct kvm *kvm, struct kvm_msi *msi)
153 struct kvm_kernel_irq_routing_entry route;
155 if (!irqchip_in_kernel(kvm) || msi->flags != 0)
158 route.msi.address_lo = msi->address_lo;
159 route.msi.address_hi = msi->address_hi;
160 route.msi.data = msi->data;
162 return kvm_set_msi(&route, kvm, KVM_USERSPACE_IRQ_SOURCE_ID, 1);
167 * < 0 Interrupt was ignored (masked or not delivered for other reasons)
168 * = 0 Interrupt was coalesced (previous irq is still pending)
169 * > 0 Number of CPUs interrupt was delivered to
171 int kvm_set_irq(struct kvm *kvm, int irq_source_id, u32 irq, int level)
173 struct kvm_kernel_irq_routing_entry *e, irq_set[KVM_NR_IRQCHIPS];
175 struct kvm_irq_routing_table *irq_rt;
176 struct hlist_node *n;
178 trace_kvm_set_irq(irq, level, irq_source_id);
180 /* Not possible to detect if the guest uses the PIC or the
181 * IOAPIC. So set the bit in both. The guest will ignore
182 * writes to the unused one.
185 irq_rt = rcu_dereference(kvm->irq_routing);
186 if (irq < irq_rt->nr_rt_entries)
187 hlist_for_each_entry(e, n, &irq_rt->map[irq], link)
193 r = irq_set[i].set(&irq_set[i], kvm, irq_source_id, level);
197 ret = r + ((ret < 0) ? 0 : ret);
204 * Deliver an IRQ in an atomic context if we can, or return a failure,
205 * user can retry in a process context.
207 * -EWOULDBLOCK - Can't deliver in atomic context: retry in a process context.
208 * Other values - No need to retry.
210 int kvm_set_irq_inatomic(struct kvm *kvm, int irq_source_id, u32 irq, int level)
212 struct kvm_kernel_irq_routing_entry *e;
214 struct kvm_irq_routing_table *irq_rt;
215 struct hlist_node *n;
217 trace_kvm_set_irq(irq, level, irq_source_id);
220 * Injection into either PIC or IOAPIC might need to scan all CPUs,
221 * which would need to be retried from thread context; when same GSI
222 * is connected to both PIC and IOAPIC, we'd have to report a
223 * partial failure here.
224 * Since there's no easy way to do this, we only support injecting MSI
225 * which is limited to 1:1 GSI mapping.
228 irq_rt = rcu_dereference(kvm->irq_routing);
229 if (irq < irq_rt->nr_rt_entries)
230 hlist_for_each_entry(e, n, &irq_rt->map[irq], link) {
231 if (likely(e->type == KVM_IRQ_ROUTING_MSI))
232 ret = kvm_set_msi_inatomic(e, kvm);
241 bool kvm_irq_has_notifier(struct kvm *kvm, unsigned irqchip, unsigned pin)
243 struct kvm_irq_ack_notifier *kian;
244 struct hlist_node *n;
248 gsi = rcu_dereference(kvm->irq_routing)->chip[irqchip][pin];
250 hlist_for_each_entry_rcu(kian, n, &kvm->irq_ack_notifier_list,
252 if (kian->gsi == gsi) {
261 EXPORT_SYMBOL_GPL(kvm_irq_has_notifier);
263 void kvm_notify_acked_irq(struct kvm *kvm, unsigned irqchip, unsigned pin)
265 struct kvm_irq_ack_notifier *kian;
266 struct hlist_node *n;
269 trace_kvm_ack_irq(irqchip, pin);
272 gsi = rcu_dereference(kvm->irq_routing)->chip[irqchip][pin];
274 hlist_for_each_entry_rcu(kian, n, &kvm->irq_ack_notifier_list,
276 if (kian->gsi == gsi)
277 kian->irq_acked(kian);
281 void kvm_register_irq_ack_notifier(struct kvm *kvm,
282 struct kvm_irq_ack_notifier *kian)
284 mutex_lock(&kvm->irq_lock);
285 hlist_add_head_rcu(&kian->link, &kvm->irq_ack_notifier_list);
286 mutex_unlock(&kvm->irq_lock);
287 kvm_ioapic_make_eoibitmap_request(kvm);
290 void kvm_unregister_irq_ack_notifier(struct kvm *kvm,
291 struct kvm_irq_ack_notifier *kian)
293 mutex_lock(&kvm->irq_lock);
294 hlist_del_init_rcu(&kian->link);
295 mutex_unlock(&kvm->irq_lock);
297 kvm_ioapic_make_eoibitmap_request(kvm);
300 int kvm_request_irq_source_id(struct kvm *kvm)
302 unsigned long *bitmap = &kvm->arch.irq_sources_bitmap;
305 mutex_lock(&kvm->irq_lock);
306 irq_source_id = find_first_zero_bit(bitmap, BITS_PER_LONG);
308 if (irq_source_id >= BITS_PER_LONG) {
309 printk(KERN_WARNING "kvm: exhaust allocatable IRQ sources!\n");
310 irq_source_id = -EFAULT;
314 ASSERT(irq_source_id != KVM_USERSPACE_IRQ_SOURCE_ID);
316 ASSERT(irq_source_id != KVM_IRQFD_RESAMPLE_IRQ_SOURCE_ID);
318 set_bit(irq_source_id, bitmap);
320 mutex_unlock(&kvm->irq_lock);
322 return irq_source_id;
325 void kvm_free_irq_source_id(struct kvm *kvm, int irq_source_id)
327 ASSERT(irq_source_id != KVM_USERSPACE_IRQ_SOURCE_ID);
329 ASSERT(irq_source_id != KVM_IRQFD_RESAMPLE_IRQ_SOURCE_ID);
332 mutex_lock(&kvm->irq_lock);
333 if (irq_source_id < 0 ||
334 irq_source_id >= BITS_PER_LONG) {
335 printk(KERN_ERR "kvm: IRQ source ID out of range!\n");
338 clear_bit(irq_source_id, &kvm->arch.irq_sources_bitmap);
339 if (!irqchip_in_kernel(kvm))
342 kvm_ioapic_clear_all(kvm->arch.vioapic, irq_source_id);
344 kvm_pic_clear_all(pic_irqchip(kvm), irq_source_id);
347 mutex_unlock(&kvm->irq_lock);
350 void kvm_register_irq_mask_notifier(struct kvm *kvm, int irq,
351 struct kvm_irq_mask_notifier *kimn)
353 mutex_lock(&kvm->irq_lock);
355 hlist_add_head_rcu(&kimn->link, &kvm->mask_notifier_list);
356 mutex_unlock(&kvm->irq_lock);
359 void kvm_unregister_irq_mask_notifier(struct kvm *kvm, int irq,
360 struct kvm_irq_mask_notifier *kimn)
362 mutex_lock(&kvm->irq_lock);
363 hlist_del_rcu(&kimn->link);
364 mutex_unlock(&kvm->irq_lock);
368 void kvm_fire_mask_notifiers(struct kvm *kvm, unsigned irqchip, unsigned pin,
371 struct kvm_irq_mask_notifier *kimn;
372 struct hlist_node *n;
376 gsi = rcu_dereference(kvm->irq_routing)->chip[irqchip][pin];
378 hlist_for_each_entry_rcu(kimn, n, &kvm->mask_notifier_list, link)
379 if (kimn->irq == gsi)
380 kimn->func(kimn, mask);
384 void kvm_free_irq_routing(struct kvm *kvm)
386 /* Called only during vm destruction. Nobody can use the pointer
388 kfree(kvm->irq_routing);
391 static int setup_routing_entry(struct kvm_irq_routing_table *rt,
392 struct kvm_kernel_irq_routing_entry *e,
393 const struct kvm_irq_routing_entry *ue)
398 struct kvm_kernel_irq_routing_entry *ei;
399 struct hlist_node *n;
402 * Do not allow GSI to be mapped to the same irqchip more than once.
403 * Allow only one to one mapping between GSI and MSI.
405 hlist_for_each_entry(ei, n, &rt->map[ue->gsi], link)
406 if (ei->type == KVM_IRQ_ROUTING_MSI ||
407 ue->type == KVM_IRQ_ROUTING_MSI ||
408 ue->u.irqchip.irqchip == ei->irqchip.irqchip)
414 case KVM_IRQ_ROUTING_IRQCHIP:
416 switch (ue->u.irqchip.irqchip) {
417 case KVM_IRQCHIP_PIC_MASTER:
418 e->set = kvm_set_pic_irq;
419 max_pin = PIC_NUM_PINS;
421 case KVM_IRQCHIP_PIC_SLAVE:
422 e->set = kvm_set_pic_irq;
423 max_pin = PIC_NUM_PINS;
426 case KVM_IRQCHIP_IOAPIC:
427 max_pin = KVM_IOAPIC_NUM_PINS;
428 e->set = kvm_set_ioapic_irq;
433 e->irqchip.irqchip = ue->u.irqchip.irqchip;
434 e->irqchip.pin = ue->u.irqchip.pin + delta;
435 if (e->irqchip.pin >= max_pin)
437 rt->chip[ue->u.irqchip.irqchip][e->irqchip.pin] = ue->gsi;
439 case KVM_IRQ_ROUTING_MSI:
440 e->set = kvm_set_msi;
441 e->msi.address_lo = ue->u.msi.address_lo;
442 e->msi.address_hi = ue->u.msi.address_hi;
443 e->msi.data = ue->u.msi.data;
449 hlist_add_head(&e->link, &rt->map[e->gsi]);
456 int kvm_set_irq_routing(struct kvm *kvm,
457 const struct kvm_irq_routing_entry *ue,
461 struct kvm_irq_routing_table *new, *old;
462 u32 i, j, nr_rt_entries = 0;
465 for (i = 0; i < nr; ++i) {
466 if (ue[i].gsi >= KVM_MAX_IRQ_ROUTES)
468 nr_rt_entries = max(nr_rt_entries, ue[i].gsi);
473 new = kzalloc(sizeof(*new) + (nr_rt_entries * sizeof(struct hlist_head))
474 + (nr * sizeof(struct kvm_kernel_irq_routing_entry)),
480 new->rt_entries = (void *)&new->map[nr_rt_entries];
482 new->nr_rt_entries = nr_rt_entries;
483 for (i = 0; i < 3; i++)
484 for (j = 0; j < KVM_IOAPIC_NUM_PINS; j++)
485 new->chip[i][j] = -1;
487 for (i = 0; i < nr; ++i) {
491 r = setup_routing_entry(new, &new->rt_entries[i], ue);
497 mutex_lock(&kvm->irq_lock);
498 old = kvm->irq_routing;
499 kvm_irq_routing_update(kvm, new);
500 mutex_unlock(&kvm->irq_lock);
512 #define IOAPIC_ROUTING_ENTRY(irq) \
513 { .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP, \
514 .u.irqchip.irqchip = KVM_IRQCHIP_IOAPIC, .u.irqchip.pin = (irq) }
515 #define ROUTING_ENTRY1(irq) IOAPIC_ROUTING_ENTRY(irq)
518 # define PIC_ROUTING_ENTRY(irq) \
519 { .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP, \
520 .u.irqchip.irqchip = SELECT_PIC(irq), .u.irqchip.pin = (irq) % 8 }
521 # define ROUTING_ENTRY2(irq) \
522 IOAPIC_ROUTING_ENTRY(irq), PIC_ROUTING_ENTRY(irq)
524 # define ROUTING_ENTRY2(irq) \
525 IOAPIC_ROUTING_ENTRY(irq)
528 static const struct kvm_irq_routing_entry default_routing[] = {
529 ROUTING_ENTRY2(0), ROUTING_ENTRY2(1),
530 ROUTING_ENTRY2(2), ROUTING_ENTRY2(3),
531 ROUTING_ENTRY2(4), ROUTING_ENTRY2(5),
532 ROUTING_ENTRY2(6), ROUTING_ENTRY2(7),
533 ROUTING_ENTRY2(8), ROUTING_ENTRY2(9),
534 ROUTING_ENTRY2(10), ROUTING_ENTRY2(11),
535 ROUTING_ENTRY2(12), ROUTING_ENTRY2(13),
536 ROUTING_ENTRY2(14), ROUTING_ENTRY2(15),
537 ROUTING_ENTRY1(16), ROUTING_ENTRY1(17),
538 ROUTING_ENTRY1(18), ROUTING_ENTRY1(19),
539 ROUTING_ENTRY1(20), ROUTING_ENTRY1(21),
540 ROUTING_ENTRY1(22), ROUTING_ENTRY1(23),
542 ROUTING_ENTRY1(24), ROUTING_ENTRY1(25),
543 ROUTING_ENTRY1(26), ROUTING_ENTRY1(27),
544 ROUTING_ENTRY1(28), ROUTING_ENTRY1(29),
545 ROUTING_ENTRY1(30), ROUTING_ENTRY1(31),
546 ROUTING_ENTRY1(32), ROUTING_ENTRY1(33),
547 ROUTING_ENTRY1(34), ROUTING_ENTRY1(35),
548 ROUTING_ENTRY1(36), ROUTING_ENTRY1(37),
549 ROUTING_ENTRY1(38), ROUTING_ENTRY1(39),
550 ROUTING_ENTRY1(40), ROUTING_ENTRY1(41),
551 ROUTING_ENTRY1(42), ROUTING_ENTRY1(43),
552 ROUTING_ENTRY1(44), ROUTING_ENTRY1(45),
553 ROUTING_ENTRY1(46), ROUTING_ENTRY1(47),
557 int kvm_setup_default_irq_routing(struct kvm *kvm)
559 return kvm_set_irq_routing(kvm, default_routing,
560 ARRAY_SIZE(default_routing), 0);