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1/*
2 * irqchip.c: Common API for in kernel interrupt controllers
3 * Copyright (c) 2007, Intel Corporation.
4 * Copyright 2010 Red Hat, Inc. and/or its affiliates.
5 * Copyright (c) 2013, Alexander Graf <agraf@suse.de>
6 *
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms and conditions of the GNU General Public License,
9 * version 2, as published by the Free Software Foundation.
10 *
11 * This program is distributed in the hope it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
14 * more details.
15 *
16 * You should have received a copy of the GNU General Public License along with
17 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
18 * Place - Suite 330, Boston, MA 02111-1307 USA.
19 *
20 * This file is derived from virt/kvm/irq_comm.c.
21 *
22 * Authors:
23 * Yaozu (Eddie) Dong <Eddie.dong@intel.com>
24 * Alexander Graf <agraf@suse.de>
25 */
26
27#include <linux/kvm_host.h>
28#include <linux/slab.h>
29#include <linux/srcu.h>
30#include <linux/export.h>
31#include <trace/events/kvm.h>
32#include "irq.h"
33
34int kvm_irq_map_gsi(struct kvm *kvm,
35 struct kvm_kernel_irq_routing_entry *entries, int gsi)
36{
37 struct kvm_irq_routing_table *irq_rt;
38 struct kvm_kernel_irq_routing_entry *e;
39 int n = 0;
40
41 irq_rt = srcu_dereference_check(kvm->irq_routing, &kvm->irq_srcu,
42 lockdep_is_held(&kvm->irq_lock));
43 if (gsi < irq_rt->nr_rt_entries) {
44 hlist_for_each_entry(e, &irq_rt->map[gsi], link) {
45 entries[n] = *e;
46 ++n;
47 }
48 }
49
50 return n;
51}
52
53int kvm_irq_map_chip_pin(struct kvm *kvm, unsigned irqchip, unsigned pin)
54{
55 struct kvm_irq_routing_table *irq_rt;
56
57 irq_rt = srcu_dereference(kvm->irq_routing, &kvm->irq_srcu);
58 return irq_rt->chip[irqchip][pin];
59}
60
61int kvm_send_userspace_msi(struct kvm *kvm, struct kvm_msi *msi)
62{
63 struct kvm_kernel_irq_routing_entry route;
64
65 if (!irqchip_in_kernel(kvm) || msi->flags != 0)
66 return -EINVAL;
67
68 route.msi.address_lo = msi->address_lo;
69 route.msi.address_hi = msi->address_hi;
70 route.msi.data = msi->data;
71
72 return kvm_set_msi(&route, kvm, KVM_USERSPACE_IRQ_SOURCE_ID, 1, false);
73}
74
75/*
76 * Return value:
77 * < 0 Interrupt was ignored (masked or not delivered for other reasons)
78 * = 0 Interrupt was coalesced (previous irq is still pending)
79 * > 0 Number of CPUs interrupt was delivered to
80 */
81int kvm_set_irq(struct kvm *kvm, int irq_source_id, u32 irq, int level,
82 bool line_status)
83{
84 struct kvm_kernel_irq_routing_entry irq_set[KVM_NR_IRQCHIPS];
85 int ret = -1, i, idx;
86
87 trace_kvm_set_irq(irq, level, irq_source_id);
88
89 /* Not possible to detect if the guest uses the PIC or the
90 * IOAPIC. So set the bit in both. The guest will ignore
91 * writes to the unused one.
92 */
93 idx = srcu_read_lock(&kvm->irq_srcu);
94 i = kvm_irq_map_gsi(kvm, irq_set, irq);
95 srcu_read_unlock(&kvm->irq_srcu, idx);
96
97 while (i--) {
98 int r;
99 r = irq_set[i].set(&irq_set[i], kvm, irq_source_id, level,
100 line_status);
101 if (r < 0)
102 continue;
103
104 ret = r + ((ret < 0) ? 0 : ret);
105 }
106
107 return ret;
108}
109
110static void free_irq_routing_table(struct kvm_irq_routing_table *rt)
111{
112 int i;
113
114 if (!rt)
115 return;
116
117 for (i = 0; i < rt->nr_rt_entries; ++i) {
118 struct kvm_kernel_irq_routing_entry *e;
119 struct hlist_node *n;
120
121 hlist_for_each_entry_safe(e, n, &rt->map[i], link) {
122 hlist_del(&e->link);
123 kfree(e);
124 }
125 }
126
127 kfree(rt);
128}
129
130void kvm_free_irq_routing(struct kvm *kvm)
131{
132 /* Called only during vm destruction. Nobody can use the pointer
133 at this stage */
134 struct kvm_irq_routing_table *rt = rcu_access_pointer(kvm->irq_routing);
135 free_irq_routing_table(rt);
136}
137
138static int setup_routing_entry(struct kvm_irq_routing_table *rt,
139 struct kvm_kernel_irq_routing_entry *e,
140 const struct kvm_irq_routing_entry *ue)
141{
142 int r = -EINVAL;
143 struct kvm_kernel_irq_routing_entry *ei;
144
145 /*
146 * Do not allow GSI to be mapped to the same irqchip more than once.
147 * Allow only one to one mapping between GSI and non-irqchip routing.
148 */
149 hlist_for_each_entry(ei, &rt->map[ue->gsi], link)
150 if (ei->type != KVM_IRQ_ROUTING_IRQCHIP ||
151 ue->type != KVM_IRQ_ROUTING_IRQCHIP ||
152 ue->u.irqchip.irqchip == ei->irqchip.irqchip)
153 return r;
154
155 e->gsi = ue->gsi;
156 e->type = ue->type;
157 r = kvm_set_routing_entry(e, ue);
158 if (r)
159 goto out;
160 if (e->type == KVM_IRQ_ROUTING_IRQCHIP)
161 rt->chip[e->irqchip.irqchip][e->irqchip.pin] = e->gsi;
162
163 hlist_add_head(&e->link, &rt->map[e->gsi]);
164 r = 0;
165out:
166 return r;
167}
168
169void __attribute__((weak)) kvm_arch_irq_routing_update(struct kvm *kvm)
170{
171}
172
173int kvm_set_irq_routing(struct kvm *kvm,
174 const struct kvm_irq_routing_entry *ue,
175 unsigned nr,
176 unsigned flags)
177{
178 struct kvm_irq_routing_table *new, *old;
179 u32 i, j, nr_rt_entries = 0;
180 int r;
181
182 for (i = 0; i < nr; ++i) {
183 if (ue[i].gsi >= KVM_MAX_IRQ_ROUTES)
184 return -EINVAL;
185 nr_rt_entries = max(nr_rt_entries, ue[i].gsi);
186 }
187
188 nr_rt_entries += 1;
189
190 new = kzalloc(sizeof(*new) + (nr_rt_entries * sizeof(struct hlist_head)),
191 GFP_KERNEL);
192
193 if (!new)
194 return -ENOMEM;
195
196 new->nr_rt_entries = nr_rt_entries;
197 for (i = 0; i < KVM_NR_IRQCHIPS; i++)
198 for (j = 0; j < KVM_IRQCHIP_NUM_PINS; j++)
199 new->chip[i][j] = -1;
200
201 for (i = 0; i < nr; ++i) {
202 struct kvm_kernel_irq_routing_entry *e;
203
204 r = -ENOMEM;
205 e = kzalloc(sizeof(*e), GFP_KERNEL);
206 if (!e)
207 goto out;
208
209 r = -EINVAL;
210 if (ue->flags) {
211 kfree(e);
212 goto out;
213 }
214 r = setup_routing_entry(new, e, ue);
215 if (r) {
216 kfree(e);
217 goto out;
218 }
219 ++ue;
220 }
221
222 mutex_lock(&kvm->irq_lock);
223 old = kvm->irq_routing;
224 rcu_assign_pointer(kvm->irq_routing, new);
225 kvm_irq_routing_update(kvm);
226 kvm_arch_irq_routing_update(kvm);
227 mutex_unlock(&kvm->irq_lock);
228
229 kvm_arch_post_irq_routing_update(kvm);
230
231 synchronize_srcu_expedited(&kvm->irq_srcu);
232
233 new = old;
234 r = 0;
235
236out:
237 free_irq_routing_table(new);
238
239 return r;
240}
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * irqchip.c: Common API for in kernel interrupt controllers
4 * Copyright (c) 2007, Intel Corporation.
5 * Copyright 2010 Red Hat, Inc. and/or its affiliates.
6 * Copyright (c) 2013, Alexander Graf <agraf@suse.de>
7 *
8 * This file is derived from virt/kvm/irq_comm.c.
9 *
10 * Authors:
11 * Yaozu (Eddie) Dong <Eddie.dong@intel.com>
12 * Alexander Graf <agraf@suse.de>
13 */
14
15#include <linux/kvm_host.h>
16#include <linux/slab.h>
17#include <linux/srcu.h>
18#include <linux/export.h>
19#include <trace/events/kvm.h>
20
21int kvm_irq_map_gsi(struct kvm *kvm,
22 struct kvm_kernel_irq_routing_entry *entries, int gsi)
23{
24 struct kvm_irq_routing_table *irq_rt;
25 struct kvm_kernel_irq_routing_entry *e;
26 int n = 0;
27
28 irq_rt = srcu_dereference_check(kvm->irq_routing, &kvm->irq_srcu,
29 lockdep_is_held(&kvm->irq_lock));
30 if (irq_rt && gsi < irq_rt->nr_rt_entries) {
31 hlist_for_each_entry(e, &irq_rt->map[gsi], link) {
32 entries[n] = *e;
33 ++n;
34 }
35 }
36
37 return n;
38}
39
40int kvm_irq_map_chip_pin(struct kvm *kvm, unsigned irqchip, unsigned pin)
41{
42 struct kvm_irq_routing_table *irq_rt;
43
44 irq_rt = srcu_dereference(kvm->irq_routing, &kvm->irq_srcu);
45 return irq_rt->chip[irqchip][pin];
46}
47
48int kvm_send_userspace_msi(struct kvm *kvm, struct kvm_msi *msi)
49{
50 struct kvm_kernel_irq_routing_entry route;
51
52 if (!kvm_arch_irqchip_in_kernel(kvm) || (msi->flags & ~KVM_MSI_VALID_DEVID))
53 return -EINVAL;
54
55 route.msi.address_lo = msi->address_lo;
56 route.msi.address_hi = msi->address_hi;
57 route.msi.data = msi->data;
58 route.msi.flags = msi->flags;
59 route.msi.devid = msi->devid;
60
61 return kvm_set_msi(&route, kvm, KVM_USERSPACE_IRQ_SOURCE_ID, 1, false);
62}
63
64/*
65 * Return value:
66 * < 0 Interrupt was ignored (masked or not delivered for other reasons)
67 * = 0 Interrupt was coalesced (previous irq is still pending)
68 * > 0 Number of CPUs interrupt was delivered to
69 */
70int kvm_set_irq(struct kvm *kvm, int irq_source_id, u32 irq, int level,
71 bool line_status)
72{
73 struct kvm_kernel_irq_routing_entry irq_set[KVM_NR_IRQCHIPS];
74 int ret = -1, i, idx;
75
76 trace_kvm_set_irq(irq, level, irq_source_id);
77
78 /* Not possible to detect if the guest uses the PIC or the
79 * IOAPIC. So set the bit in both. The guest will ignore
80 * writes to the unused one.
81 */
82 idx = srcu_read_lock(&kvm->irq_srcu);
83 i = kvm_irq_map_gsi(kvm, irq_set, irq);
84 srcu_read_unlock(&kvm->irq_srcu, idx);
85
86 while (i--) {
87 int r;
88 r = irq_set[i].set(&irq_set[i], kvm, irq_source_id, level,
89 line_status);
90 if (r < 0)
91 continue;
92
93 ret = r + ((ret < 0) ? 0 : ret);
94 }
95
96 return ret;
97}
98
99static void free_irq_routing_table(struct kvm_irq_routing_table *rt)
100{
101 int i;
102
103 if (!rt)
104 return;
105
106 for (i = 0; i < rt->nr_rt_entries; ++i) {
107 struct kvm_kernel_irq_routing_entry *e;
108 struct hlist_node *n;
109
110 hlist_for_each_entry_safe(e, n, &rt->map[i], link) {
111 hlist_del(&e->link);
112 kfree(e);
113 }
114 }
115
116 kfree(rt);
117}
118
119void kvm_free_irq_routing(struct kvm *kvm)
120{
121 /* Called only during vm destruction. Nobody can use the pointer
122 at this stage */
123 struct kvm_irq_routing_table *rt = rcu_access_pointer(kvm->irq_routing);
124 free_irq_routing_table(rt);
125}
126
127static int setup_routing_entry(struct kvm *kvm,
128 struct kvm_irq_routing_table *rt,
129 struct kvm_kernel_irq_routing_entry *e,
130 const struct kvm_irq_routing_entry *ue)
131{
132 struct kvm_kernel_irq_routing_entry *ei;
133 int r;
134 u32 gsi = array_index_nospec(ue->gsi, KVM_MAX_IRQ_ROUTES);
135
136 /*
137 * Do not allow GSI to be mapped to the same irqchip more than once.
138 * Allow only one to one mapping between GSI and non-irqchip routing.
139 */
140 hlist_for_each_entry(ei, &rt->map[gsi], link)
141 if (ei->type != KVM_IRQ_ROUTING_IRQCHIP ||
142 ue->type != KVM_IRQ_ROUTING_IRQCHIP ||
143 ue->u.irqchip.irqchip == ei->irqchip.irqchip)
144 return -EINVAL;
145
146 e->gsi = gsi;
147 e->type = ue->type;
148 r = kvm_set_routing_entry(kvm, e, ue);
149 if (r)
150 return r;
151 if (e->type == KVM_IRQ_ROUTING_IRQCHIP)
152 rt->chip[e->irqchip.irqchip][e->irqchip.pin] = e->gsi;
153
154 hlist_add_head(&e->link, &rt->map[e->gsi]);
155
156 return 0;
157}
158
159void __attribute__((weak)) kvm_arch_irq_routing_update(struct kvm *kvm)
160{
161}
162
163bool __weak kvm_arch_can_set_irq_routing(struct kvm *kvm)
164{
165 return true;
166}
167
168int kvm_set_irq_routing(struct kvm *kvm,
169 const struct kvm_irq_routing_entry *ue,
170 unsigned nr,
171 unsigned flags)
172{
173 struct kvm_irq_routing_table *new, *old;
174 struct kvm_kernel_irq_routing_entry *e;
175 u32 i, j, nr_rt_entries = 0;
176 int r;
177
178 for (i = 0; i < nr; ++i) {
179 if (ue[i].gsi >= KVM_MAX_IRQ_ROUTES)
180 return -EINVAL;
181 nr_rt_entries = max(nr_rt_entries, ue[i].gsi);
182 }
183
184 nr_rt_entries += 1;
185
186 new = kzalloc(struct_size(new, map, nr_rt_entries), GFP_KERNEL_ACCOUNT);
187 if (!new)
188 return -ENOMEM;
189
190 new->nr_rt_entries = nr_rt_entries;
191 for (i = 0; i < KVM_NR_IRQCHIPS; i++)
192 for (j = 0; j < KVM_IRQCHIP_NUM_PINS; j++)
193 new->chip[i][j] = -1;
194
195 for (i = 0; i < nr; ++i) {
196 r = -ENOMEM;
197 e = kzalloc(sizeof(*e), GFP_KERNEL_ACCOUNT);
198 if (!e)
199 goto out;
200
201 r = -EINVAL;
202 switch (ue->type) {
203 case KVM_IRQ_ROUTING_MSI:
204 if (ue->flags & ~KVM_MSI_VALID_DEVID)
205 goto free_entry;
206 break;
207 default:
208 if (ue->flags)
209 goto free_entry;
210 break;
211 }
212 r = setup_routing_entry(kvm, new, e, ue);
213 if (r)
214 goto free_entry;
215 ++ue;
216 }
217
218 mutex_lock(&kvm->irq_lock);
219 old = rcu_dereference_protected(kvm->irq_routing, 1);
220 rcu_assign_pointer(kvm->irq_routing, new);
221 kvm_irq_routing_update(kvm);
222 kvm_arch_irq_routing_update(kvm);
223 mutex_unlock(&kvm->irq_lock);
224
225 kvm_arch_post_irq_routing_update(kvm);
226
227 synchronize_srcu_expedited(&kvm->irq_srcu);
228
229 new = old;
230 r = 0;
231 goto out;
232
233free_entry:
234 kfree(e);
235out:
236 free_irq_routing_table(new);
237
238 return r;
239}
240
241/*
242 * Allocate empty IRQ routing by default so that additional setup isn't needed
243 * when userspace-driven IRQ routing is activated, and so that kvm->irq_routing
244 * is guaranteed to be non-NULL.
245 */
246int kvm_init_irq_routing(struct kvm *kvm)
247{
248 struct kvm_irq_routing_table *new;
249 int chip_size;
250
251 new = kzalloc(struct_size(new, map, 1), GFP_KERNEL_ACCOUNT);
252 if (!new)
253 return -ENOMEM;
254
255 new->nr_rt_entries = 1;
256
257 chip_size = sizeof(int) * KVM_NR_IRQCHIPS * KVM_IRQCHIP_NUM_PINS;
258 memset(new->chip, -1, chip_size);
259
260 RCU_INIT_POINTER(kvm->irq_routing, new);
261
262 return 0;
263}