Re: [PATCH 1/3] KVM: Ioctls for init MSI-X entry

Marcelo Tosatti
2009-02-16T23:24:03Z

On Mon, Feb 16, 2009 at 01:49:29PM +0800, Sheng Yang wrote:
> (oops... fix a typo)
>
> Introduce KVM_SET_MSIX_NR and KVM_SET_MSIX_ENTRY two ioctls.
>
> This two ioctls are used by userspace to specific guest device MSI-X entry
> number and correlate MSI-X entry with GSI during the initialization stage.
>
> MSI-X should be well initialzed before enabling.
>
> Don't support change MSI-X entry number for now.
>
> Signed-off-by: Sheng Yang <sheng@linux.intel.com>
> ---
> include/linux/kvm.h | 16 +++++++
> include/linux/kvm_host.h | 3 +
> virt/kvm/kvm_main.c | 103 ++++++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 122 insertions(+), 0 deletions(-)
>
> diff --git a/include/linux/kvm.h b/include/linux/kvm.h
> index 2163b3d..a2dfbe0 100644
> --- a/include/linux/kvm.h
> +++ b/include/linux/kvm.h
> @@ -475,6 +475,8 @@ struct kvm_irq_routing {
> #define KVM_ASSIGN_IRQ _IOR(KVMIO, 0x70, \
> struct kvm_assigned_irq)
> #define KVM_REINJECT_CONTROL _IO(KVMIO, 0x71)
> +#define KVM_SET_MSIX_NR _IOR(KVMIO, 0x72, struct kvm_assigned_msix_nr)
> +#define KVM_SET_MSIX_ENTRY _IOR(KVMIO, 0x73, struct kvm_assigned_msix_entry)
>
> /*
> * ioctls for vcpu fds
> @@ -595,4 +597,18 @@ struct kvm_assigned_irq {
> #define KVM_DEV_IRQ_ASSIGN_MSI_ACTION KVM_DEV_IRQ_ASSIGN_ENABLE_MSI
> #define KVM_DEV_IRQ_ASSIGN_ENABLE_MSI (1 << 0)
>
> +struct kvm_assigned_msix_nr {
> + __u32 assigned_dev_id;
> + __u16 entry_nr;
> + __u16 padding;
> +};
> +
> +#define KVM_MAX_MSIX_PER_DEV 512
> +struct kvm_assigned_msix_entry {
> + __u32 assigned_dev_id;
> + __u32 gsi;
> + __u16 entry; /* The index of entry in the MSI-X table */
> + __u16 padding[3];
> +};
> +
> #endif
> diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
> index 7c7096d..ac4d63c 100644
> --- a/include/linux/kvm_host.h
> +++ b/include/linux/kvm_host.h
> @@ -326,9 +326,12 @@ struct kvm_assigned_dev_kernel {
> int assigned_dev_id;
> int host_busnr;
> int host_devfn;
> + int entries_nr;
> int host_irq;
> bool host_irq_disabled;
> + struct msix_entry *host_msix_entries;
> int guest_irq;
> + struct msix_entry *guest_msix_entries;
> #define KVM_ASSIGNED_DEV_GUEST_INTX (1 << 0)
> #define KVM_ASSIGNED_DEV_GUEST_MSI (1 << 1)
> #define KVM_ASSIGNED_DEV_HOST_INTX (1 << 8)
> diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
> index 266bdaf..bb4aa73 100644
> --- a/virt/kvm/kvm_main.c
> +++ b/virt/kvm/kvm_main.c
> @@ -1593,6 +1593,87 @@ static int kvm_vcpu_ioctl_set_sigmask(struct kvm_vcpu *vcpu, sigset_t *sigset)
> return 0;
> }
>
> +static int kvm_vm_ioctl_set_msix_nr(struct kvm *kvm,
> + struct kvm_assigned_msix_nr *entry_nr)
> +{
> + int r = 0;
> + struct kvm_assigned_dev_kernel *adev;
> +
> + mutex_lock(&kvm->lock);
> +
> + adev = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
> + entry_nr->assigned_dev_id);
> + if (!adev) {
> + r = -EINVAL;
> + goto msix_nr_out;
> + }
> +
> + if (adev->entries_nr == 0) {
> + adev->entries_nr = entry_nr->entry_nr;
> + if (adev->entries_nr == 0 ||

<= 0 ?

> + adev->entries_nr >= KVM_MAX_MSIX_PER_DEV)

Otherwise looks OK, thanks.