blob: 7f256f31df102e36da59a8ebed636f1c9615cb00 [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];
36 struct kvm_kernel_irq_routing_entry *rt_entries;
37 u32 nr_rt_entries;
38 /*
39 * Array indexed by gsi. Each entry contains list of irq chips
40 * the gsi is connected to.
41 */
42 struct hlist_head map[0];
43};
44
45int kvm_irq_map_gsi(struct kvm *kvm,
46 struct kvm_kernel_irq_routing_entry *entries, int gsi)
Paul Mackerras8ba918d2014-06-30 20:51:10 +100047{
Paul Mackerras9957c862014-06-30 20:51:11 +100048 struct kvm_irq_routing_table *irq_rt;
Paul Mackerras8ba918d2014-06-30 20:51:10 +100049 struct kvm_kernel_irq_routing_entry *e;
50 int n = 0;
51
Paul Mackerras9957c862014-06-30 20:51:11 +100052 irq_rt = srcu_dereference_check(kvm->irq_routing, &kvm->irq_srcu,
53 lockdep_is_held(&kvm->irq_lock));
Paul Mackerras8ba918d2014-06-30 20:51:10 +100054 if (gsi < irq_rt->nr_rt_entries) {
55 hlist_for_each_entry(e, &irq_rt->map[gsi], link) {
56 entries[n] = *e;
57 ++n;
58 }
59 }
60
61 return n;
62}
63
Paul Mackerras9957c862014-06-30 20:51:11 +100064int kvm_irq_map_chip_pin(struct kvm *kvm, unsigned irqchip, unsigned pin)
Paul Mackerras8ba918d2014-06-30 20:51:10 +100065{
Paul Mackerras9957c862014-06-30 20:51:11 +100066 struct kvm_irq_routing_table *irq_rt;
67
68 irq_rt = srcu_dereference(kvm->irq_routing, &kvm->irq_srcu);
Paul Mackerras8ba918d2014-06-30 20:51:10 +100069 return irq_rt->chip[irqchip][pin];
70}
71
Alexander Graf1c9f8522013-04-15 23:04:10 +020072int kvm_send_userspace_msi(struct kvm *kvm, struct kvm_msi *msi)
73{
74 struct kvm_kernel_irq_routing_entry route;
75
76 if (!irqchip_in_kernel(kvm) || msi->flags != 0)
77 return -EINVAL;
78
79 route.msi.address_lo = msi->address_lo;
80 route.msi.address_hi = msi->address_hi;
81 route.msi.data = msi->data;
82
83 return kvm_set_msi(&route, kvm, KVM_USERSPACE_IRQ_SOURCE_ID, 1, false);
84}
85
86/*
87 * Return value:
88 * < 0 Interrupt was ignored (masked or not delivered for other reasons)
89 * = 0 Interrupt was coalesced (previous irq is still pending)
90 * > 0 Number of CPUs interrupt was delivered to
91 */
92int kvm_set_irq(struct kvm *kvm, int irq_source_id, u32 irq, int level,
93 bool line_status)
94{
Paul Mackerras8ba918d2014-06-30 20:51:10 +100095 struct kvm_kernel_irq_routing_entry irq_set[KVM_NR_IRQCHIPS];
96 int ret = -1, i, idx;
Alexander Graf1c9f8522013-04-15 23:04:10 +020097
98 trace_kvm_set_irq(irq, level, irq_source_id);
99
100 /* Not possible to detect if the guest uses the PIC or the
101 * IOAPIC. So set the bit in both. The guest will ignore
102 * writes to the unused one.
103 */
Christian Borntraeger719d93c2014-01-16 13:44:20 +0100104 idx = srcu_read_lock(&kvm->irq_srcu);
Paul Mackerras9957c862014-06-30 20:51:11 +1000105 i = kvm_irq_map_gsi(kvm, irq_set, irq);
Christian Borntraeger719d93c2014-01-16 13:44:20 +0100106 srcu_read_unlock(&kvm->irq_srcu, idx);
Alexander Graf1c9f8522013-04-15 23:04:10 +0200107
108 while(i--) {
109 int r;
110 r = irq_set[i].set(&irq_set[i], kvm, irq_source_id, level,
111 line_status);
112 if (r < 0)
113 continue;
114
115 ret = r + ((ret < 0) ? 0 : ret);
116 }
117
118 return ret;
119}
120
121void kvm_free_irq_routing(struct kvm *kvm)
122{
123 /* Called only during vm destruction. Nobody can use the pointer
124 at this stage */
125 kfree(kvm->irq_routing);
126}
Alexander Grafe8cde092013-04-15 23:23:21 +0200127
128static int setup_routing_entry(struct kvm_irq_routing_table *rt,
129 struct kvm_kernel_irq_routing_entry *e,
130 const struct kvm_irq_routing_entry *ue)
131{
132 int r = -EINVAL;
133 struct kvm_kernel_irq_routing_entry *ei;
134
135 /*
136 * Do not allow GSI to be mapped to the same irqchip more than once.
137 * Allow only one to one mapping between GSI and MSI.
138 */
139 hlist_for_each_entry(ei, &rt->map[ue->gsi], link)
140 if (ei->type == KVM_IRQ_ROUTING_MSI ||
141 ue->type == KVM_IRQ_ROUTING_MSI ||
142 ue->u.irqchip.irqchip == ei->irqchip.irqchip)
143 return r;
144
145 e->gsi = ue->gsi;
146 e->type = ue->type;
Paul Mackerras8ba918d2014-06-30 20:51:10 +1000147 r = kvm_set_routing_entry(e, ue);
Alexander Grafe8cde092013-04-15 23:23:21 +0200148 if (r)
149 goto out;
Paul Mackerras8ba918d2014-06-30 20:51:10 +1000150 if (e->type == KVM_IRQ_ROUTING_IRQCHIP)
151 rt->chip[e->irqchip.irqchip][e->irqchip.pin] = e->gsi;
Alexander Grafe8cde092013-04-15 23:23:21 +0200152
153 hlist_add_head(&e->link, &rt->map[e->gsi]);
154 r = 0;
155out:
156 return r;
157}
158
159int kvm_set_irq_routing(struct kvm *kvm,
160 const struct kvm_irq_routing_entry *ue,
161 unsigned nr,
162 unsigned flags)
163{
164 struct kvm_irq_routing_table *new, *old;
165 u32 i, j, nr_rt_entries = 0;
166 int r;
167
168 for (i = 0; i < nr; ++i) {
169 if (ue[i].gsi >= KVM_MAX_IRQ_ROUTES)
170 return -EINVAL;
171 nr_rt_entries = max(nr_rt_entries, ue[i].gsi);
172 }
173
174 nr_rt_entries += 1;
175
176 new = kzalloc(sizeof(*new) + (nr_rt_entries * sizeof(struct hlist_head))
177 + (nr * sizeof(struct kvm_kernel_irq_routing_entry)),
178 GFP_KERNEL);
179
180 if (!new)
181 return -ENOMEM;
182
183 new->rt_entries = (void *)&new->map[nr_rt_entries];
184
185 new->nr_rt_entries = nr_rt_entries;
186 for (i = 0; i < KVM_NR_IRQCHIPS; i++)
187 for (j = 0; j < KVM_IRQCHIP_NUM_PINS; j++)
188 new->chip[i][j] = -1;
189
190 for (i = 0; i < nr; ++i) {
191 r = -EINVAL;
192 if (ue->flags)
193 goto out;
194 r = setup_routing_entry(new, &new->rt_entries[i], ue);
195 if (r)
196 goto out;
197 ++ue;
198 }
199
200 mutex_lock(&kvm->irq_lock);
201 old = kvm->irq_routing;
Paul Mackerras9957c862014-06-30 20:51:11 +1000202 rcu_assign_pointer(kvm->irq_routing, new);
203 kvm_irq_routing_update(kvm);
Alexander Grafe8cde092013-04-15 23:23:21 +0200204 mutex_unlock(&kvm->irq_lock);
205
Christian Borntraeger719d93c2014-01-16 13:44:20 +0100206 synchronize_srcu_expedited(&kvm->irq_srcu);
Alexander Grafe8cde092013-04-15 23:23:21 +0200207
208 new = old;
209 r = 0;
210
211out:
212 kfree(new);
213 return r;
214}