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
kvm_set_pic_irq(struct kvm_kernel_irq_routing_entry * e,struct kvm * kvm,int irq_source_id,int level,bool line_status)30 static 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
kvm_set_ioapic_irq(struct kvm_kernel_irq_routing_entry * e,struct kvm * kvm,int irq_source_id,int level,bool line_status)38 static 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
kvm_irq_delivery_to_apic(struct kvm * kvm,struct kvm_lapic * src,struct kvm_lapic_irq * irq,struct dest_map * dest_map)47 int 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
kvm_set_msi_irq(struct kvm * kvm,struct kvm_kernel_irq_routing_entry * e,struct kvm_lapic_irq * irq)104 void 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 }
123 EXPORT_SYMBOL_GPL(kvm_set_msi_irq);
124
kvm_msi_route_invalid(struct kvm * kvm,struct kvm_kernel_irq_routing_entry * e)125 static 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
kvm_set_msi(struct kvm_kernel_irq_routing_entry * e,struct kvm * kvm,int irq_source_id,int level,bool line_status)131 int 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
kvm_hv_set_sint(struct kvm_kernel_irq_routing_entry * e,struct kvm * kvm,int irq_source_id,int level,bool line_status)148 static 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
kvm_arch_set_irq_inatomic(struct kvm_kernel_irq_routing_entry * e,struct kvm * kvm,int irq_source_id,int level,bool line_status)159 int 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
kvm_request_irq_source_id(struct kvm * kvm)197 int 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);
214 unlock:
215 mutex_unlock(&kvm->irq_lock);
216
217 return irq_source_id;
218 }
219
kvm_free_irq_source_id(struct kvm * kvm,int irq_source_id)220 void 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);
237 unlock:
238 mutex_unlock(&kvm->irq_lock);
239 }
240
kvm_register_irq_mask_notifier(struct kvm * kvm,int irq,struct kvm_irq_mask_notifier * kimn)241 void 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
kvm_unregister_irq_mask_notifier(struct kvm * kvm,int irq,struct kvm_irq_mask_notifier * kimn)250 void 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
kvm_fire_mask_notifiers(struct kvm * kvm,unsigned irqchip,unsigned pin,bool mask)259 void 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
kvm_arch_can_set_irq_routing(struct kvm * kvm)274 bool kvm_arch_can_set_irq_routing(struct kvm *kvm)
275 {
276 return irqchip_in_kernel(kvm);
277 }
278
kvm_set_routing_entry(struct kvm * kvm,struct kvm_kernel_irq_routing_entry * e,const struct kvm_irq_routing_entry * ue)279 int 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
kvm_intr_is_single_vcpu(struct kvm * kvm,struct kvm_lapic_irq * irq,struct kvm_vcpu ** dest_vcpu)338 bool 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 }
364 EXPORT_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
377 static 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
kvm_setup_default_irq_routing(struct kvm * kvm)392 int 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
kvm_arch_post_irq_routing_update(struct kvm * kvm)398 void kvm_arch_post_irq_routing_update(struct kvm *kvm)
399 {
400 if (!irqchip_split(kvm))
401 return;
402 kvm_make_scan_ioapic_request(kvm);
403 }
404
kvm_scan_ioapic_routes(struct kvm_vcpu * vcpu,ulong * ioapic_handled_vectors)405 void kvm_scan_ioapic_routes(struct kvm_vcpu *vcpu,
406 ulong *ioapic_handled_vectors)
407 {
408 struct kvm *kvm = vcpu->kvm;
409 struct kvm_kernel_irq_routing_entry *entry;
410 struct kvm_irq_routing_table *table;
411 u32 i, nr_ioapic_pins;
412 int idx;
413
414 idx = srcu_read_lock(&kvm->irq_srcu);
415 table = srcu_dereference(kvm->irq_routing, &kvm->irq_srcu);
416 nr_ioapic_pins = min_t(u32, table->nr_rt_entries,
417 kvm->arch.nr_reserved_ioapic_pins);
418 for (i = 0; i < nr_ioapic_pins; ++i) {
419 hlist_for_each_entry(entry, &table->map[i], link) {
420 struct kvm_lapic_irq irq;
421
422 if (entry->type != KVM_IRQ_ROUTING_MSI)
423 continue;
424
425 kvm_set_msi_irq(vcpu->kvm, entry, &irq);
426
427 if (irq.trig_mode &&
428 (kvm_apic_match_dest(vcpu, NULL, APIC_DEST_NOSHORT,
429 irq.dest_id, irq.dest_mode) ||
430 kvm_apic_pending_eoi(vcpu, irq.vector)))
431 __set_bit(irq.vector, ioapic_handled_vectors);
432 }
433 }
434 srcu_read_unlock(&kvm->irq_srcu, idx);
435 }
436
kvm_arch_irq_routing_update(struct kvm * kvm)437 void kvm_arch_irq_routing_update(struct kvm *kvm)
438 {
439 #ifdef CONFIG_KVM_HYPERV
440 kvm_hv_irq_routing_update(kvm);
441 #endif
442 }
443