Re: [PATCH 1/2] kvm: libkvm: support for irq routing

Sheng Yang
2009-01-15T06:17:20Z

On Wednesday 14 January 2009 21:53:10 Avi Kivity wrote:
> Signed-off-by: Avi Kivity <avi@redhat.com>

Do we need a lock for the table?

--
regards
Yang, Sheng

> ---
> libkvm/kvm-common.h | 4 ++
> libkvm/libkvm.c | 107
> +++++++++++++++++++++++++++++++++++++++++++++++++++ libkvm/libkvm.h |
> 62 +++++++++++++++++++++++++++++
> 3 files changed, 173 insertions(+), 0 deletions(-)
>
> diff --git a/libkvm/kvm-common.h b/libkvm/kvm-common.h
> index c5beacc..e09c07c 100644
> --- a/libkvm/kvm-common.h
> +++ b/libkvm/kvm-common.h
> @@ -61,6 +61,10 @@ struct kvm_context {
> int pit_in_kernel;
> /// in-kernel coalesced mmio
> int coalesced_mmio;
> +#ifdef KVM_CAP_IRQ_ROUTING
> + struct kvm_irq_routing *irq_routes;
> + int nr_allocated_irq_routes;
> +#endif
> };
>
> void init_slots(void);
> diff --git a/libkvm/libkvm.c b/libkvm/libkvm.c
> index 0408fdb..1004fa6 100644
> --- a/libkvm/libkvm.c
> +++ b/libkvm/libkvm.c
> @@ -381,6 +381,14 @@ int kvm_create_vm(kvm_context_t kvm)
> {
> int fd = kvm->fd;
>
> +#ifdef KVM_CAP_IRQ_ROUTING
> + kvm->irq_routes = malloc(sizeof(*kvm->irq_routes));
> + if (!kvm->irq_routes)
> + return -ENOMEM;
> + memset(kvm->irq_routes, 0, sizeof(*kvm->irq_routes));
> + kvm->nr_allocated_irq_routes = 0;
> +#endif
> +
> kvm->vcpu_fd[0] = -1;
>
> fd = ioctl(fd, KVM_CREATE_VM, 0);
> @@ -1164,3 +1172,102 @@ int kvm_reinject_control(kvm_context_t kvm, int
> pit_reinject) #endif
> return -ENOSYS;
> }
> +
> +int kvm_has_gsi_routing(kvm_context_t kvm)
> +{
> + int r = 0;
> +
> +#ifdef KVM_CAP_IRQ_ROUTING
> + r = kvm_check_extension(kvm, KVM_CAP_IRQ_ROUTING);
> +#endif
> + return r;
> +}
> +
> +int kvm_get_gsi_count(kvm_context_t kvm)
> +{
> +#ifdef KVM_CAP_IRQ_ROUTING
> + return kvm_check_extension(kvm, KVM_CAP_IRQ_ROUTING);
> +#else
> + return -EINVAL;
> +#endif
> +}
> +
> +int kvm_clear_gsi_routes(kvm_context_t kvm)
> +{
> +#ifdef KVM_CAP_IRQ_ROUTING
> + kvm->irq_routes->nr = 0;
> + return 0;
> +#else
> + return -EINVAL;
> +#endif
> +}
> +
> +int kvm_add_irq_route(kvm_context_t kvm, int gsi, int irqchip, int pin)
> +{
> +#ifdef KVM_CAP_IRQ_ROUTING
> + struct kvm_irq_routing *z;
> + struct kvm_irq_routing_entry *e;
> + int n, size;
> +
> + if (kvm->irq_routes->nr == kvm->nr_allocated_irq_routes) {
> + n = kvm->nr_allocated_irq_routes * 2;
> + if (n < 64)
> + n = 64;
> + size = sizeof(struct kvm_irq_routing);
> + size += n * sizeof(*e);
> + z = realloc(kvm->irq_routes, size);
> + if (!z)
> + return -ENOMEM;
> + kvm->nr_allocated_irq_routes = n;
> + kvm->irq_routes = z;
> + }
> + n = kvm->irq_routes->nr++;
> + e = &kvm->irq_routes->entries[n];
> + memset(e, 0, sizeof(*e));
> + e->gsi = gsi;
> + e->type = KVM_IRQ_ROUTING_IRQCHIP;
> + e->flags = 0;
> + e->u.irqchip.irqchip = irqchip;
> + e->u.irqchip.pin = pin;
> + return 0;
> +#else
> + return -ENOSYS;
> +#endif
> +}
> +
> +int kvm_del_irq_route(kvm_context_t kvm, int gsi, int irqchip, int pin)
> +{
> +#ifdef KVM_CAP_IRQ_ROUTING
> + struct kvm_irq_routing_entry *e, *p;
> + int i;
> +
> + for (i = 0; i < kvm->irq_routes->nr; ++i) {
> + e = &kvm->irq_routes->entries[i];
> + if (e->type == KVM_IRQ_ROUTING_IRQCHIP
> + && e->gsi == gsi
> + && e->u.irqchip.irqchip == irqchip
> + && e->u.irqchip.pin == pin) {
> + p = &kvm->irq_routes->entries[--kvm->irq_routes->nr];
> + *e = *p;
> + return 0;
> + }
> + }
> + return -ESRCH;
> +#else
> + return -ENOSYS;
> +#endif
> +}
> +
> +int kvm_commit_irq_routes(kvm_context_t kvm)
> +{
> +#ifdef KVM_CAP_IRQ_ROUTING
> + int r;
> +
> + kvm->irq_routes->flags = 0;
> + r = ioctl(kvm->vm_fd, KVM_SET_GSI_ROUTING, kvm->irq_routes);
> + if (r == -1)
> + r = -errno;
> +#else
> + return -ENOSYS;
> +#endif
> +}
> diff --git a/libkvm/libkvm.h b/libkvm/libkvm.h
> index ee1ba68..85012ff 100644
> --- a/libkvm/libkvm.h
> +++ b/libkvm/libkvm.h
> @@ -720,4 +720,66 @@ int kvm_assign_irq(kvm_context_t kvm,
> */
> int kvm_destroy_memory_region_works(kvm_context_t kvm);
> #endif
> +
> +
> +/*!
> + * \brief Checks whether the generic irq routing capability is present
> + *
> + * Checks whether kvm can reroute interrupts among the various interrupt
> + * controllers.
> + *
> + * \param kvm Pointer to the current kvm_context
> + */
> +int kvm_has_gsi_routing(kvm_context_t kvm);
> +
> +/*!
> + * \brief Determines the number of gsis that can be routed
> + *
> + * Returns the number of distinct gsis that can be routed by kvm. This is
> + * also the number of distinct routes (if a gsi has two routes, than
> another + * gsi cannot be used...)
> + *
> + * \param kvm Pointer to the current kvm_context
> + */
> +int kvm_get_gsi_count(kvm_context_t kvm);
> +
> +/*!
> + * \brief Clears the temporary irq routing table
> + *
> + * Clears the temporary irq routing table. Nothing is committed to the
> + * running VM.
> + *
> + * \param kvm Pointer to the current kvm_context
> + */
> +int kvm_clear_gsi_routes(kvm_context_t kvm);
> +
> +/*!
> + * \brief Adds an irq route to the temporary irq routing table
> + *
> + * Adds an irq route to the temporary irq routing table. Nothing is
> + * committed to the running VM.
> + *
> + * \param kvm Pointer to the current kvm_context
> + */
> +int kvm_add_irq_route(kvm_context_t kvm, int gsi, int irqchip, int pin);
> +
> +/*!
> + * \brief Removes an irq route from the temporary irq routing table
> + *
> + * Adds an irq route to the temporary irq routing table. Nothing is
> + * committed to the running VM.
> + *
> + * \param kvm Pointer to the current kvm_context
> + */
> +int kvm_del_irq_route(kvm_context_t kvm, int gsi, int irqchip, int pin);
> +
> +/*!
> + * \brief Commit the temporary irq routing table
> + *
> + * Commit the temporary irq routing table to the running VM.
> + *
> + * \param kvm Pointer to the current kvm_context
> + */
> +int kvm_commit_irq_routes(kvm_context_t kvm);
> +
> #endif