1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * irq_comm.c: Common API for in kernel interrupt controller
4 * Copyright (c) 2007, Intel Corporation.
5 *
6 * Authors:
7 *   Yaozu (Eddie) Dong <Eddie.dong@intel.com>
8 *
9 * Copyright 2010 Red Hat, Inc. and/or its affiliates.
10 */
11#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
12
13#include <linux/kvm_host.h>
14#include <linux/slab.h>
15#include <linux/export.h>
16#include <linux/rculist.h>
17
18#include <trace/events/kvm.h>
19
20#include "irq.h"
21
22#include "ioapic.h"
23
24#include "lapic.h"
25
26#include "hyperv.h"
27#include "x86.h"
28#include "xen.h"
29
30static int kvm_set_pic_irq(struct kvm_kernel_irq_routing_entry *e,
31			   struct kvm *kvm, int irq_source_id, int level,
32			   bool line_status)
33{
34	struct kvm_pic *pic = kvm->arch.vpic;
35	return kvm_pic_set_irq(pic, e->irqchip.pin, irq_source_id, level);
36}
37
38static int kvm_set_ioapic_irq(struct kvm_kernel_irq_routing_entry *e,
39			      struct kvm *kvm, int irq_source_id, int level,
40			      bool line_status)
41{
42	struct kvm_ioapic *ioapic = kvm->arch.vioapic;
43	return kvm_ioapic_set_irq(ioapic, e->irqchip.pin, irq_source_id, level,
44				line_status);
45}
46
47int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src,
48		struct kvm_lapic_irq *irq, struct dest_map *dest_map)
49{
50	int r = -1;
51	struct kvm_vcpu *vcpu, *lowest = NULL;
52	unsigned long i, dest_vcpu_bitmap[BITS_TO_LONGS(KVM_MAX_VCPUS)];
53	unsigned int dest_vcpus = 0;
54
55	if (kvm_irq_delivery_to_apic_fast(kvm, src, irq, &r, dest_map))
56		return r;
57
58	if (irq->dest_mode == APIC_DEST_PHYSICAL &&
59	    irq->dest_id == 0xff && kvm_lowest_prio_delivery(irq)) {
60		pr_info("apic: phys broadcast and lowest prio\n");
61		irq->delivery_mode = APIC_DM_FIXED;
62	}
63
64	memset(dest_vcpu_bitmap, 0, sizeof(dest_vcpu_bitmap));
65
66	kvm_for_each_vcpu(i, vcpu, kvm) {
67		if (!kvm_apic_present(vcpu))
68			continue;
69
70		if (!kvm_apic_match_dest(vcpu, src, irq->shorthand,
71					irq->dest_id, irq->dest_mode))
72			continue;
73
74		if (!kvm_lowest_prio_delivery(irq)) {
75			if (r < 0)
76				r = 0;
77			r += kvm_apic_set_irq(vcpu, irq, dest_map);
78		} else if (kvm_apic_sw_enabled(vcpu->arch.apic)) {
79			if (!kvm_vector_hashing_enabled()) {
80				if (!lowest)
81					lowest = vcpu;
82				else if (kvm_apic_compare_prio(vcpu, lowest) < 0)
83					lowest = vcpu;
84			} else {
85				__set_bit(i, dest_vcpu_bitmap);
86				dest_vcpus++;
87			}
88		}
89	}
90
91	if (dest_vcpus != 0) {
92		int idx = kvm_vector_to_index(irq->vector, dest_vcpus,
93					dest_vcpu_bitmap, KVM_MAX_VCPUS);
94
95		lowest = kvm_get_vcpu(kvm, idx);
96	}
97
98	if (lowest)
99		r = kvm_apic_set_irq(lowest, irq, dest_map);
100
101	return r;
102}
103
104void kvm_set_msi_irq(struct kvm *kvm, struct kvm_kernel_irq_routing_entry *e,
105		     struct kvm_lapic_irq *irq)
106{
107	struct msi_msg msg = { .address_lo = e->msi.address_lo,
108			       .address_hi = e->msi.address_hi,
109			       .data = e->msi.data };
110
111	trace_kvm_msi_set_irq(msg.address_lo | (kvm->arch.x2apic_format ?
112			      (u64)msg.address_hi << 32 : 0), msg.data);
113
114	irq->dest_id = x86_msi_msg_get_destid(&msg, kvm->arch.x2apic_format);
115	irq->vector = msg.arch_data.vector;
116	irq->dest_mode = kvm_lapic_irq_dest_mode(msg.arch_addr_lo.dest_mode_logical);
117	irq->trig_mode = msg.arch_data.is_level;
118	irq->delivery_mode = msg.arch_data.delivery_mode << 8;
119	irq->msi_redir_hint = msg.arch_addr_lo.redirect_hint;
120	irq->level = 1;
121	irq->shorthand = APIC_DEST_NOSHORT;
122}
123EXPORT_SYMBOL_GPL(kvm_set_msi_irq);
124
125static inline bool kvm_msi_route_invalid(struct kvm *kvm,
126		struct kvm_kernel_irq_routing_entry *e)
127{
128	return kvm->arch.x2apic_format && (e->msi.address_hi & 0xff);
129}
130
131int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
132		struct kvm *kvm, int irq_source_id, int level, bool line_status)
133{
134	struct kvm_lapic_irq irq;
135
136	if (kvm_msi_route_invalid(kvm, e))
137		return -EINVAL;
138
139	if (!level)
140		return -1;
141
142	kvm_set_msi_irq(kvm, e, &irq);
143
144	return kvm_irq_delivery_to_apic(kvm, NULL, &irq, NULL);
145}
146
147#ifdef CONFIG_KVM_HYPERV
148static int kvm_hv_set_sint(struct kvm_kernel_irq_routing_entry *e,
149		    struct kvm *kvm, int irq_source_id, int level,
150		    bool line_status)
151{
152	if (!level)
153		return -1;
154
155	return kvm_hv_synic_set_irq(kvm, e->hv_sint.vcpu, e->hv_sint.sint);
156}
157#endif
158
159int kvm_arch_set_irq_inatomic(struct kvm_kernel_irq_routing_entry *e,
160			      struct kvm *kvm, int irq_source_id, int level,
161			      bool line_status)
162{
163	struct kvm_lapic_irq irq;
164	int r;
165
166	switch (e->type) {
167#ifdef CONFIG_KVM_HYPERV
168	case KVM_IRQ_ROUTING_HV_SINT:
169		return kvm_hv_set_sint(e, kvm, irq_source_id, level,
170				       line_status);
171#endif
172
173	case KVM_IRQ_ROUTING_MSI:
174		if (kvm_msi_route_invalid(kvm, e))
175			return -EINVAL;
176
177		kvm_set_msi_irq(kvm, e, &irq);
178
179		if (kvm_irq_delivery_to_apic_fast(kvm, NULL, &irq, &r, NULL))
180			return r;
181		break;
182
183#ifdef CONFIG_KVM_XEN
184	case KVM_IRQ_ROUTING_XEN_EVTCHN:
185		if (!level)
186			return -1;
187
188		return kvm_xen_set_evtchn_fast(&e->xen_evtchn, kvm);
189#endif
190	default:
191		break;
192	}
193
194	return -EWOULDBLOCK;
195}
196
197int kvm_request_irq_source_id(struct kvm *kvm)
198{
199	unsigned long *bitmap = &kvm->arch.irq_sources_bitmap;
200	int irq_source_id;
201
202	mutex_lock(&kvm->irq_lock);
203	irq_source_id = find_first_zero_bit(bitmap, BITS_PER_LONG);
204
205	if (irq_source_id >= BITS_PER_LONG) {
206		pr_warn("exhausted allocatable IRQ sources!\n");
207		irq_source_id = -EFAULT;
208		goto unlock;
209	}
210
211	ASSERT(irq_source_id != KVM_USERSPACE_IRQ_SOURCE_ID);
212	ASSERT(irq_source_id != KVM_IRQFD_RESAMPLE_IRQ_SOURCE_ID);
213	set_bit(irq_source_id, bitmap);
214unlock:
215	mutex_unlock(&kvm->irq_lock);
216
217	return irq_source_id;
218}
219
220void kvm_free_irq_source_id(struct kvm *kvm, int irq_source_id)
221{
222	ASSERT(irq_source_id != KVM_USERSPACE_IRQ_SOURCE_ID);
223	ASSERT(irq_source_id != KVM_IRQFD_RESAMPLE_IRQ_SOURCE_ID);
224
225	mutex_lock(&kvm->irq_lock);
226	if (irq_source_id < 0 ||
227	    irq_source_id >= BITS_PER_LONG) {
228		pr_err("IRQ source ID out of range!\n");
229		goto unlock;
230	}
231	clear_bit(irq_source_id, &kvm->arch.irq_sources_bitmap);
232	if (!irqchip_kernel(kvm))
233		goto unlock;
234
235	kvm_ioapic_clear_all(kvm->arch.vioapic, irq_source_id);
236	kvm_pic_clear_all(kvm->arch.vpic, irq_source_id);
237unlock:
238	mutex_unlock(&kvm->irq_lock);
239}
240
241void kvm_register_irq_mask_notifier(struct kvm *kvm, int irq,
242				    struct kvm_irq_mask_notifier *kimn)
243{
244	mutex_lock(&kvm->irq_lock);
245	kimn->irq = irq;
246	hlist_add_head_rcu(&kimn->link, &kvm->arch.mask_notifier_list);
247	mutex_unlock(&kvm->irq_lock);
248}
249
250void kvm_unregister_irq_mask_notifier(struct kvm *kvm, int irq,
251				      struct kvm_irq_mask_notifier *kimn)
252{
253	mutex_lock(&kvm->irq_lock);
254	hlist_del_rcu(&kimn->link);
255	mutex_unlock(&kvm->irq_lock);
256	synchronize_srcu(&kvm->irq_srcu);
257}
258
259void kvm_fire_mask_notifiers(struct kvm *kvm, unsigned irqchip, unsigned pin,
260			     bool mask)
261{
262	struct kvm_irq_mask_notifier *kimn;
263	int idx, gsi;
264
265	idx = srcu_read_lock(&kvm->irq_srcu);
266	gsi = kvm_irq_map_chip_pin(kvm, irqchip, pin);
267	if (gsi != -1)
268		hlist_for_each_entry_rcu(kimn, &kvm->arch.mask_notifier_list, link)
269			if (kimn->irq == gsi)
270				kimn->func(kimn, mask);
271	srcu_read_unlock(&kvm->irq_srcu, idx);
272}
273
274bool kvm_arch_can_set_irq_routing(struct kvm *kvm)
275{
276	return irqchip_in_kernel(kvm);
277}
278
279int kvm_set_routing_entry(struct kvm *kvm,
280			  struct kvm_kernel_irq_routing_entry *e,
281			  const struct kvm_irq_routing_entry *ue)
282{
283	/* We can't check irqchip_in_kernel() here as some callers are
284	 * currently initializing the irqchip. Other callers should therefore
285	 * check kvm_arch_can_set_irq_routing() before calling this function.
286	 */
287	switch (ue->type) {
288	case KVM_IRQ_ROUTING_IRQCHIP:
289		if (irqchip_split(kvm))
290			return -EINVAL;
291		e->irqchip.pin = ue->u.irqchip.pin;
292		switch (ue->u.irqchip.irqchip) {
293		case KVM_IRQCHIP_PIC_SLAVE:
294			e->irqchip.pin += PIC_NUM_PINS / 2;
295			fallthrough;
296		case KVM_IRQCHIP_PIC_MASTER:
297			if (ue->u.irqchip.pin >= PIC_NUM_PINS / 2)
298				return -EINVAL;
299			e->set = kvm_set_pic_irq;
300			break;
301		case KVM_IRQCHIP_IOAPIC:
302			if (ue->u.irqchip.pin >= KVM_IOAPIC_NUM_PINS)
303				return -EINVAL;
304			e->set = kvm_set_ioapic_irq;
305			break;
306		default:
307			return -EINVAL;
308		}
309		e->irqchip.irqchip = ue->u.irqchip.irqchip;
310		break;
311	case KVM_IRQ_ROUTING_MSI:
312		e->set = kvm_set_msi;
313		e->msi.address_lo = ue->u.msi.address_lo;
314		e->msi.address_hi = ue->u.msi.address_hi;
315		e->msi.data = ue->u.msi.data;
316
317		if (kvm_msi_route_invalid(kvm, e))
318			return -EINVAL;
319		break;
320#ifdef CONFIG_KVM_HYPERV
321	case KVM_IRQ_ROUTING_HV_SINT:
322		e->set = kvm_hv_set_sint;
323		e->hv_sint.vcpu = ue->u.hv_sint.vcpu;
324		e->hv_sint.sint = ue->u.hv_sint.sint;
325		break;
326#endif
327#ifdef CONFIG_KVM_XEN
328	case KVM_IRQ_ROUTING_XEN_EVTCHN:
329		return kvm_xen_setup_evtchn(kvm, e, ue);
330#endif
331	default:
332		return -EINVAL;
333	}
334
335	return 0;
336}
337
338bool kvm_intr_is_single_vcpu(struct kvm *kvm, struct kvm_lapic_irq *irq,
339			     struct kvm_vcpu **dest_vcpu)
340{
341	int r = 0;
342	unsigned long i;
343	struct kvm_vcpu *vcpu;
344
345	if (kvm_intr_is_single_vcpu_fast(kvm, irq, dest_vcpu))
346		return true;
347
348	kvm_for_each_vcpu(i, vcpu, kvm) {
349		if (!kvm_apic_present(vcpu))
350			continue;
351
352		if (!kvm_apic_match_dest(vcpu, NULL, irq->shorthand,
353					irq->dest_id, irq->dest_mode))
354			continue;
355
356		if (++r == 2)
357			return false;
358
359		*dest_vcpu = vcpu;
360	}
361
362	return r == 1;
363}
364EXPORT_SYMBOL_GPL(kvm_intr_is_single_vcpu);
365
366#define IOAPIC_ROUTING_ENTRY(irq) \
367	{ .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP,	\
368	  .u.irqchip = { .irqchip = KVM_IRQCHIP_IOAPIC, .pin = (irq) } }
369#define ROUTING_ENTRY1(irq) IOAPIC_ROUTING_ENTRY(irq)
370
371#define PIC_ROUTING_ENTRY(irq) \
372	{ .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP,	\
373	  .u.irqchip = { .irqchip = SELECT_PIC(irq), .pin = (irq) % 8 } }
374#define ROUTING_ENTRY2(irq) \
375	IOAPIC_ROUTING_ENTRY(irq), PIC_ROUTING_ENTRY(irq)
376
377static const struct kvm_irq_routing_entry default_routing[] = {
378	ROUTING_ENTRY2(0), ROUTING_ENTRY2(1),
379	ROUTING_ENTRY2(2), ROUTING_ENTRY2(3),
380	ROUTING_ENTRY2(4), ROUTING_ENTRY2(5),
381	ROUTING_ENTRY2(6), ROUTING_ENTRY2(7),
382	ROUTING_ENTRY2(8), ROUTING_ENTRY2(9),
383	ROUTING_ENTRY2(10), ROUTING_ENTRY2(11),
384	ROUTING_ENTRY2(12), ROUTING_ENTRY2(13),
385	ROUTING_ENTRY2(14), ROUTING_ENTRY2(15),
386	ROUTING_ENTRY1(16), ROUTING_ENTRY1(17),
387	ROUTING_ENTRY1(18), ROUTING_ENTRY1(19),
388	ROUTING_ENTRY1(20), ROUTING_ENTRY1(21),
389	ROUTING_ENTRY1(22), ROUTING_ENTRY1(23),
390};
391
392int kvm_setup_default_irq_routing(struct kvm *kvm)
393{
394	return kvm_set_irq_routing(kvm, default_routing,
395				   ARRAY_SIZE(default_routing), 0);
396}
397
398static const struct kvm_irq_routing_entry empty_routing[] = {};
399
400int kvm_setup_empty_irq_routing(struct kvm *kvm)
401{
402	return kvm_set_irq_routing(kvm, empty_routing, 0, 0);
403}
404
405void kvm_arch_post_irq_routing_update(struct kvm *kvm)
406{
407	if (!irqchip_split(kvm))
408		return;
409	kvm_make_scan_ioapic_request(kvm);
410}
411
412void kvm_scan_ioapic_routes(struct kvm_vcpu *vcpu,
413			    ulong *ioapic_handled_vectors)
414{
415	struct kvm *kvm = vcpu->kvm;
416	struct kvm_kernel_irq_routing_entry *entry;
417	struct kvm_irq_routing_table *table;
418	u32 i, nr_ioapic_pins;
419	int idx;
420
421	idx = srcu_read_lock(&kvm->irq_srcu);
422	table = srcu_dereference(kvm->irq_routing, &kvm->irq_srcu);
423	nr_ioapic_pins = min_t(u32, table->nr_rt_entries,
424			       kvm->arch.nr_reserved_ioapic_pins);
425	for (i = 0; i < nr_ioapic_pins; ++i) {
426		hlist_for_each_entry(entry, &table->map[i], link) {
427			struct kvm_lapic_irq irq;
428
429			if (entry->type != KVM_IRQ_ROUTING_MSI)
430				continue;
431
432			kvm_set_msi_irq(vcpu->kvm, entry, &irq);
433
434			if (irq.trig_mode &&
435			    (kvm_apic_match_dest(vcpu, NULL, APIC_DEST_NOSHORT,
436						 irq.dest_id, irq.dest_mode) ||
437			     kvm_apic_pending_eoi(vcpu, irq.vector)))
438				__set_bit(irq.vector, ioapic_handled_vectors);
439		}
440	}
441	srcu_read_unlock(&kvm->irq_srcu, idx);
442}
443
444void kvm_arch_irq_routing_update(struct kvm *kvm)
445{
446#ifdef CONFIG_KVM_HYPERV
447	kvm_hv_irq_routing_update(kvm);
448#endif
449}
450