blob: 21c14244f4c4fd1c3c8ffade7f3265df91c89efb [file] [log] [blame]
Alexander Graf1c9f8522013-04-15 23:04:10 +02001/*
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>
Christian Borntraeger719d93c2014-01-16 13:44:20 +010029#include <linux/srcu.h>
Alexander Graf1c9f8522013-04-15 23:04:10 +020030#include <linux/export.h>
31#include <trace/events/kvm.h>
32#include "irq.h"
33
Paul Mackerras9957c862014-06-30 20:51:11 +100034struct kvm_irq_routing_table {
35 int chip[KVM_NR_IRQCHIPS][KVM_IRQCHIP_NUM_PINS];
Paul Mackerras9957c862014-06-30 20:51:11 +100036 u32 nr_rt_entries;
37 /*
38 * Array indexed by gsi. Each entry contains list of irq chips
39 * the gsi is connected to.
40 */
41 struct hlist_head map[0];
42};
43
44int kvm_irq_map_gsi(struct kvm *kvm,
45 struct kvm_kernel_irq_routing_entry *entries, int gsi)
Paul Mackerras8ba918d2014-06-30 20:51:10 +100046{
Paul Mackerras9957c862014-06-30 20:51:11 +100047 struct kvm_irq_routing_table *irq_rt;
Paul Mackerras8ba918d2014-06-30 20:51:10 +100048 struct kvm_kernel_irq_routing_entry *e;
49 int n = 0;
50
Paul Mackerras9957c862014-06-30 20:51:11 +100051 irq_rt = srcu_dereference_check(kvm->irq_routing, &kvm->irq_srcu,
52 lockdep_is_held(&kvm->irq_lock));
Paul Mackerras8ba918d2014-06-30 20:51:10 +100053 if (gsi < irq_rt->nr_rt_entries) {
54 hlist_for_each_entry(e, &irq_rt->map[gsi], link) {
55 entries[n] = *e;
56 ++n;
57 }
58 }
59
60 return n;
61}
62
Paul Mackerras9957c862014-06-30 20:51:11 +100063int kvm_irq_map_chip_pin(struct kvm *kvm, unsigned irqchip, unsigned pin)
Paul Mackerras8ba918d2014-06-30 20:51:10 +100064{
Paul Mackerras9957c862014-06-30 20:51:11 +100065 struct kvm_irq_routing_table *irq_rt;
66
67 irq_rt = srcu_dereference(kvm->irq_routing, &kvm->irq_srcu);
Paul Mackerras8ba918d2014-06-30 20:51:10 +100068 return irq_rt->chip[irqchip][pin];
69}
70
Alexander Graf1c9f8522013-04-15 23:04:10 +020071int kvm_send_userspace_msi(struct kvm *kvm, struct kvm_msi *msi)
72{
73 struct kvm_kernel_irq_routing_entry route;
74
75 if (!irqchip_in_kernel(kvm) || msi->flags != 0)
76 return -EINVAL;
77
78 route.msi.address_lo = msi->address_lo;
79 route.msi.address_hi = msi->address_hi;
80 route.msi.data = msi->data;
81
82 return kvm_set_msi(&route, kvm, KVM_USERSPACE_IRQ_SOURCE_ID, 1, false);
83}
84
85/*
86 * Return value:
87 * < 0 Interrupt was ignored (masked or not delivered for other reasons)
88 * = 0 Interrupt was coalesced (previous irq is still pending)
89 * > 0 Number of CPUs interrupt was delivered to
90 */
91int kvm_set_irq(struct kvm *kvm, int irq_source_id, u32 irq, int level,
92 bool line_status)
93{
Paul Mackerras8ba918d2014-06-30 20:51:10 +100094 struct kvm_kernel_irq_routing_entry irq_set[KVM_NR_IRQCHIPS];
95 int ret = -1, i, idx;
Alexander Graf1c9f8522013-04-15 23:04:10 +020096
97 trace_kvm_set_irq(irq, level, irq_source_id);
98
99 /* Not possible to detect if the guest uses the PIC or the
100 * IOAPIC. So set the bit in both. The guest will ignore
101 * writes to the unused one.
102 */
Christian Borntraeger719d93c2014-01-16 13:44:20 +0100103 idx = srcu_read_lock(&kvm->irq_srcu);
Paul Mackerras9957c862014-06-30 20:51:11 +1000104 i = kvm_irq_map_gsi(kvm, irq_set, irq);
Christian Borntraeger719d93c2014-01-16 13:44:20 +0100105 srcu_read_unlock(&kvm->irq_srcu, idx);
Alexander Graf1c9f8522013-04-15 23:04:10 +0200106
Kevin Mulveyae548c52015-02-20 08:21:37 -0500107 while (i--) {
Alexander Graf1c9f8522013-04-15 23:04:10 +0200108 int r;
109 r = irq_set[i].set(&irq_set[i], kvm, irq_source_id, level,
110 line_status);
111 if (r < 0)
112 continue;
113
114 ret = r + ((ret < 0) ? 0 : ret);
115 }
116
117 return ret;
118}
119
Joerg Roedele73f61e2015-05-08 14:31:44 +0200120static void free_irq_routing_table(struct kvm_irq_routing_table *rt)
121{
122 int i;
123
124 if (!rt)
125 return;
126
127 for (i = 0; i < rt->nr_rt_entries; ++i) {
128 struct kvm_kernel_irq_routing_entry *e;
129 struct hlist_node *n;
130
131 hlist_for_each_entry_safe(e, n, &rt->map[i], link) {
132 hlist_del(&e->link);
133 kfree(e);
134 }
135 }
136
137 kfree(rt);
138}
139
Alexander Graf1c9f8522013-04-15 23:04:10 +0200140void kvm_free_irq_routing(struct kvm *kvm)
141{
142 /* Called only during vm destruction. Nobody can use the pointer
143 at this stage */
Joerg Roedele73f61e2015-05-08 14:31:44 +0200144 struct kvm_irq_routing_table *rt = rcu_access_pointer(kvm->irq_routing);
145 free_irq_routing_table(rt);
Alexander Graf1c9f8522013-04-15 23:04:10 +0200146}
Alexander Grafe8cde092013-04-15 23:23:21 +0200147
148static int setup_routing_entry(struct kvm_irq_routing_table *rt,
149 struct kvm_kernel_irq_routing_entry *e,
150 const struct kvm_irq_routing_entry *ue)
151{
152 int r = -EINVAL;
153 struct kvm_kernel_irq_routing_entry *ei;
154
155 /*
156 * Do not allow GSI to be mapped to the same irqchip more than once.
157 * Allow only one to one mapping between GSI and MSI.
158 */
159 hlist_for_each_entry(ei, &rt->map[ue->gsi], link)
160 if (ei->type == KVM_IRQ_ROUTING_MSI ||
161 ue->type == KVM_IRQ_ROUTING_MSI ||
162 ue->u.irqchip.irqchip == ei->irqchip.irqchip)
163 return r;
164
165 e->gsi = ue->gsi;
166 e->type = ue->type;
Paul Mackerras8ba918d2014-06-30 20:51:10 +1000167 r = kvm_set_routing_entry(e, ue);
Alexander Grafe8cde092013-04-15 23:23:21 +0200168 if (r)
169 goto out;
Paul Mackerras8ba918d2014-06-30 20:51:10 +1000170 if (e->type == KVM_IRQ_ROUTING_IRQCHIP)
171 rt->chip[e->irqchip.irqchip][e->irqchip.pin] = e->gsi;
Alexander Grafe8cde092013-04-15 23:23:21 +0200172
173 hlist_add_head(&e->link, &rt->map[e->gsi]);
174 r = 0;
175out:
176 return r;
177}
178
179int kvm_set_irq_routing(struct kvm *kvm,
180 const struct kvm_irq_routing_entry *ue,
181 unsigned nr,
182 unsigned flags)
183{
184 struct kvm_irq_routing_table *new, *old;
185 u32 i, j, nr_rt_entries = 0;
186 int r;
187
188 for (i = 0; i < nr; ++i) {
189 if (ue[i].gsi >= KVM_MAX_IRQ_ROUTES)
190 return -EINVAL;
191 nr_rt_entries = max(nr_rt_entries, ue[i].gsi);
192 }
193
194 nr_rt_entries += 1;
195
Joerg Roedele73f61e2015-05-08 14:31:44 +0200196 new = kzalloc(sizeof(*new) + (nr_rt_entries * sizeof(struct hlist_head)),
Alexander Grafe8cde092013-04-15 23:23:21 +0200197 GFP_KERNEL);
198
199 if (!new)
200 return -ENOMEM;
201
Alexander Grafe8cde092013-04-15 23:23:21 +0200202 new->nr_rt_entries = nr_rt_entries;
203 for (i = 0; i < KVM_NR_IRQCHIPS; i++)
204 for (j = 0; j < KVM_IRQCHIP_NUM_PINS; j++)
205 new->chip[i][j] = -1;
206
207 for (i = 0; i < nr; ++i) {
Joerg Roedele73f61e2015-05-08 14:31:44 +0200208 struct kvm_kernel_irq_routing_entry *e;
209
210 r = -ENOMEM;
211 e = kzalloc(sizeof(*e), GFP_KERNEL);
212 if (!e)
213 goto out;
214
Alexander Grafe8cde092013-04-15 23:23:21 +0200215 r = -EINVAL;
216 if (ue->flags)
217 goto out;
Joerg Roedele73f61e2015-05-08 14:31:44 +0200218 r = setup_routing_entry(new, e, ue);
Alexander Grafe8cde092013-04-15 23:23:21 +0200219 if (r)
220 goto out;
221 ++ue;
222 }
223
224 mutex_lock(&kvm->irq_lock);
225 old = kvm->irq_routing;
Paul Mackerras9957c862014-06-30 20:51:11 +1000226 rcu_assign_pointer(kvm->irq_routing, new);
227 kvm_irq_routing_update(kvm);
Alexander Grafe8cde092013-04-15 23:23:21 +0200228 mutex_unlock(&kvm->irq_lock);
229
Christian Borntraeger719d93c2014-01-16 13:44:20 +0100230 synchronize_srcu_expedited(&kvm->irq_srcu);
Alexander Grafe8cde092013-04-15 23:23:21 +0200231
232 new = old;
233 r = 0;
234
235out:
Joerg Roedele73f61e2015-05-08 14:31:44 +0200236 free_irq_routing_table(new);
237
Alexander Grafe8cde092013-04-15 23:23:21 +0200238 return r;
239}