vgic-irqfd.c

Go to the documentation of this file.

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2015, 2016 ARM Ltd.
 */
 
#include <linux/kvm.h>
#include <linux/kvm_host.h>
#include <trace/events/kvm.h>
#include <kvm/arm_vgic.h>
#include "vgic.h"
 
/**
 * vgic_irqfd_set_irq: inject the IRQ corresponding to the
 * irqchip routing entry
 *
 * This is the entry point for irqfd IRQ injection
 */
static int vgic_irqfd_set_irq(struct kvm_kernel_irq_routing_entry *e,
            struct kvm *kvm, int irq_source_id,
            int level, bool line_status)
{
    unsigned int spi_id = e->irqchip.pin + VGIC_NR_PRIVATE_IRQS;
 
    if (!vgic_valid_spi(kvm, spi_id))
        return -EINVAL;
    return kvm_vgic_inject_irq(kvm, NULL, spi_id, level, NULL);
}
 
/**
 * kvm_set_routing_entry: populate a kvm routing entry
 * from a user routing entry
 *
 * @kvm: the VM this entry is applied to
 * @e: kvm kernel routing entry handle
 * @ue: user api routing entry handle
 * return 0 on success, -EINVAL on errors.
 */
int kvm_set_routing_entry(struct kvm *kvm,
              struct kvm_kernel_irq_routing_entry *e,
              const struct kvm_irq_routing_entry *ue)
{
    int r = -EINVAL;
 
    switch (ue->type) {
    case KVM_IRQ_ROUTING_IRQCHIP:
        e->set = vgic_irqfd_set_irq;
        e->irqchip.irqchip = ue->u.irqchip.irqchip;
        e->irqchip.pin = ue->u.irqchip.pin;
        if ((e->irqchip.pin >= KVM_IRQCHIP_NUM_PINS) ||
            (e->irqchip.irqchip >= KVM_NR_IRQCHIPS))
            goto out;
        break;
    case KVM_IRQ_ROUTING_MSI:
        e->set = kvm_set_msi;
        e->msi.address_lo = ue->u.msi.address_lo;
        e->msi.address_hi = ue->u.msi.address_hi;
        e->msi.data = ue->u.msi.data;
        e->msi.flags = ue->flags;
        e->msi.devid = ue->u.msi.devid;
        break;
    default:
        goto out;
    }
    r = 0;
out:
    return r;
}
 
static void kvm_populate_msi(struct kvm_kernel_irq_routing_entry *e,
                 struct kvm_msi *msi)
{
    msi->address_lo = e->msi.address_lo;
    msi->address_hi = e->msi.address_hi;
    msi->data = e->msi.data;
    msi->flags = e->msi.flags;
    msi->devid = e->msi.devid;
}
/**
 * kvm_set_msi: inject the MSI corresponding to the
 * MSI routing entry
 *
 * This is the entry point for irqfd MSI injection
 * and userspace MSI injection.
 */
int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
        struct kvm *kvm, int irq_source_id,
        int level, bool line_status)
{
    struct kvm_msi msi;
 
    if (!vgic_has_its(kvm))
        return -ENODEV;
 
    if (!level)
        return -1;
 
    kvm_populate_msi(e, &msi);
    return vgic_its_inject_msi(kvm, &msi);
}
 
/**
 * kvm_arch_set_irq_inatomic: fast-path for irqfd injection
 */
int kvm_arch_set_irq_inatomic(struct kvm_kernel_irq_routing_entry *e,
                  struct kvm *kvm, int irq_source_id, int level,
                  bool line_status)
{
    if (!level)
        return -EWOULDBLOCK;
 
    switch (e->type) {
    case KVM_IRQ_ROUTING_MSI: {
        struct kvm_msi msi;
 
        if (!vgic_has_its(kvm))
            break;
 
        kvm_populate_msi(e, &msi);
        return vgic_its_inject_cached_translation(kvm, &msi);
    }
 
    case KVM_IRQ_ROUTING_IRQCHIP:
        /*
         * Injecting SPIs is always possible in atomic context
         * as long as the damn vgic is initialized.
         */
        if (unlikely(!vgic_initialized(kvm)))
            break;
        return vgic_irqfd_set_irq(e, kvm, irq_source_id, 1, line_status);
    }
 
    return -EWOULDBLOCK;
}
 
int kvm_vgic_setup_default_irq_routing(struct kvm *kvm)
{
    struct kvm_irq_routing_entry *entries;
    struct vgic_dist *dist = &kvm->arch.vgic;
    u32 nr = dist->nr_spis;
    int i, ret;
 
    entries = kcalloc(nr, sizeof(*entries), GFP_KERNEL_ACCOUNT);
    if (!entries)
        return -ENOMEM;
 
    for (i = 0; i < nr; i++) {
        entries[i].gsi = i;
        entries[i].type = KVM_IRQ_ROUTING_IRQCHIP;
        entries[i].u.irqchip.irqchip = 0;
        entries[i].u.irqchip.pin = i;
    }
    ret = kvm_set_irq_routing(kvm, entries, nr, 0);
    kfree(entries);
    return ret;
}