LXR linux/arch/arm64/kvm/vgic/vgic-irqfd.c

   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 */
  18static 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 */
  38int 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;
  65out:
  66        return r;
  67}
  68
  69static 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 */
  85int 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 */
 104int kvm_arch_set_irq_inatomic(struct kvm_kernel_irq_routing_entry *e,
 105                              struct kvm *kvm, int irq_source_id, int level,
 106                              bool line_status)
 107{
 108        if (!level)
 109                return -EWOULDBLOCK;
 110
 111        switch (e->type) {
 112        case KVM_IRQ_ROUTING_MSI: {
 113                struct kvm_msi msi;
 114
 115                if (!vgic_has_its(kvm))
 116                        break;
 117
 118                kvm_populate_msi(e, &msi);
 119                return vgic_its_inject_cached_translation(kvm, &msi);
 120        }
 121
 122        case KVM_IRQ_ROUTING_IRQCHIP:
 123                /*
 124                 * Injecting SPIs is always possible in atomic context
 125                 * as long as the damn vgic is initialized.
 126                 */
 127                if (unlikely(!vgic_initialized(kvm)))
 128                        break;
 129                return vgic_irqfd_set_irq(e, kvm, irq_source_id, 1, line_status);
 130        }
 131
 132        return -EWOULDBLOCK;
 133}
 134
 135int kvm_vgic_setup_default_irq_routing(struct kvm *kvm)
 136{
 137        struct kvm_irq_routing_entry *entries;
 138        struct vgic_dist *dist = &kvm->arch.vgic;
 139        u32 nr = dist->nr_spis;
 140        int i, ret;
 141
 142        entries = kcalloc(nr, sizeof(*entries), GFP_KERNEL);
 143        if (!entries)
 144                return -ENOMEM;
 145
 146        for (i = 0; i < nr; i++) {
 147                entries[i].gsi = i;
 148                entries[i].type = KVM_IRQ_ROUTING_IRQCHIP;
 149                entries[i].u.irqchip.irqchip = 0;
 150                entries[i].u.irqchip.pin = i;
 151        }
 152        ret = kvm_set_irq_routing(kvm, entries, nr, 0);
 153        kfree(entries);
 154        return ret;
 155}
 156