xref: /linux/arch/arm64/kvm/vgic/vgic-irqfd.c (revision 95298d63c67673c654c08952672d016212b26054)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2015, 2016 ARM Ltd.
4  */
5 
6 #include <linux/kvm.h>
7 #include <linux/kvm_host.h>
8 #include <trace/events/kvm.h>
9 #include <kvm/arm_vgic.h>
10 #include "vgic.h"
11 
12 /**
13  * vgic_irqfd_set_irq: inject the IRQ corresponding to the
14  * irqchip routing entry
15  *
16  * This is the entry point for irqfd IRQ injection
17  */
18 static int vgic_irqfd_set_irq(struct kvm_kernel_irq_routing_entry *e,
19 			struct kvm *kvm, int irq_source_id,
20 			int level, bool line_status)
21 {
22 	unsigned int spi_id = e->irqchip.pin + VGIC_NR_PRIVATE_IRQS;
23 
24 	if (!vgic_valid_spi(kvm, spi_id))
25 		return -EINVAL;
26 	return kvm_vgic_inject_irq(kvm, 0, spi_id, level, NULL);
27 }
28 
29 /**
30  * kvm_set_routing_entry: populate a kvm routing entry
31  * from a user routing entry
32  *
33  * @kvm: the VM this entry is applied to
34  * @e: kvm kernel routing entry handle
35  * @ue: user api routing entry handle
36  * return 0 on success, -EINVAL on errors.
37  */
38 int kvm_set_routing_entry(struct kvm *kvm,
39 			  struct kvm_kernel_irq_routing_entry *e,
40 			  const struct kvm_irq_routing_entry *ue)
41 {
42 	int r = -EINVAL;
43 
44 	switch (ue->type) {
45 	case KVM_IRQ_ROUTING_IRQCHIP:
46 		e->set = vgic_irqfd_set_irq;
47 		e->irqchip.irqchip = ue->u.irqchip.irqchip;
48 		e->irqchip.pin = ue->u.irqchip.pin;
49 		if ((e->irqchip.pin >= KVM_IRQCHIP_NUM_PINS) ||
50 		    (e->irqchip.irqchip >= KVM_NR_IRQCHIPS))
51 			goto out;
52 		break;
53 	case KVM_IRQ_ROUTING_MSI:
54 		e->set = kvm_set_msi;
55 		e->msi.address_lo = ue->u.msi.address_lo;
56 		e->msi.address_hi = ue->u.msi.address_hi;
57 		e->msi.data = ue->u.msi.data;
58 		e->msi.flags = ue->flags;
59 		e->msi.devid = ue->u.msi.devid;
60 		break;
61 	default:
62 		goto out;
63 	}
64 	r = 0;
65 out:
66 	return r;
67 }
68 
69 static void kvm_populate_msi(struct kvm_kernel_irq_routing_entry *e,
70 			     struct kvm_msi *msi)
71 {
72 	msi->address_lo = e->msi.address_lo;
73 	msi->address_hi = e->msi.address_hi;
74 	msi->data = e->msi.data;
75 	msi->flags = e->msi.flags;
76 	msi->devid = e->msi.devid;
77 }
78 /**
79  * kvm_set_msi: inject the MSI corresponding to the
80  * MSI routing entry
81  *
82  * This is the entry point for irqfd MSI injection
83  * and userspace MSI injection.
84  */
85 int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
86 		struct kvm *kvm, int irq_source_id,
87 		int level, bool line_status)
88 {
89 	struct kvm_msi msi;
90 
91 	if (!vgic_has_its(kvm))
92 		return -ENODEV;
93 
94 	if (!level)
95 		return -1;
96 
97 	kvm_populate_msi(e, &msi);
98 	return vgic_its_inject_msi(kvm, &msi);
99 }
100 
101 /**
102  * kvm_arch_set_irq_inatomic: fast-path for irqfd injection
103  *
104  * Currently only direct MSI injection is supported.
105  */
106 int kvm_arch_set_irq_inatomic(struct kvm_kernel_irq_routing_entry *e,
107 			      struct kvm *kvm, int irq_source_id, int level,
108 			      bool line_status)
109 {
110 	if (e->type == KVM_IRQ_ROUTING_MSI && vgic_has_its(kvm) && level) {
111 		struct kvm_msi msi;
112 
113 		kvm_populate_msi(e, &msi);
114 		if (!vgic_its_inject_cached_translation(kvm, &msi))
115 			return 0;
116 	}
117 
118 	return -EWOULDBLOCK;
119 }
120 
121 int kvm_vgic_setup_default_irq_routing(struct kvm *kvm)
122 {
123 	struct kvm_irq_routing_entry *entries;
124 	struct vgic_dist *dist = &kvm->arch.vgic;
125 	u32 nr = dist->nr_spis;
126 	int i, ret;
127 
128 	entries = kcalloc(nr, sizeof(*entries), GFP_KERNEL);
129 	if (!entries)
130 		return -ENOMEM;
131 
132 	for (i = 0; i < nr; i++) {
133 		entries[i].gsi = i;
134 		entries[i].type = KVM_IRQ_ROUTING_IRQCHIP;
135 		entries[i].u.irqchip.irqchip = 0;
136 		entries[i].u.irqchip.pin = i;
137 	}
138 	ret = kvm_set_irq_routing(kvm, entries, nr, 0);
139 	kfree(entries);
140 	return ret;
141 }
142