Hi Feng,
On 12/03/2014 08:39 AM, Feng Wu wrote:
> This patch adds the kvm-vfio interface for VT-d Posted-Interrrupts.
> When guests updates MSI/MSI-x information for an assigned-device,
update
> QEMU will use KVM_DEV_VFIO_DEVICE_POSTING_IRQ attribute to setup
> IRTE for VT-d PI. This patch implement this IRQ attribute.
s/implement/implements
>
> Signed-off-by: Feng Wu <feng...@intel.com>
> ---
> include/linux/kvm_host.h | 19 ++++++++
> virt/kvm/vfio.c | 103
> ++++++++++++++++++++++++++++++++++++++++++++++
> 2 files changed, 122 insertions(+), 0 deletions(-)
>
> diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
> index 5cd4420..8d06678 100644
> --- a/include/linux/kvm_host.h
> +++ b/include/linux/kvm_host.h
> @@ -1134,6 +1134,25 @@ static inline int kvm_arch_vfio_set_forward(struct
> kvm_fwd_irq *fwd_irq,
> }
> #endif
>
> +#ifdef __KVM_HAVE_ARCH_KVM_VFIO_POSTING
> +/*
> + * kvm_arch_vfio_update_pi_irte - set IRTE for Posted-Interrupts
> + *
> + * @kvm: kvm
> + * @host_irq: host irq of the interrupt
> + * @guest_irq: gsi of the interrupt
> + * returns 0 on success, < 0 on failure
> + */
> +int kvm_arch_vfio_update_pi_irte(struct kvm *kvm, unsigned int host_irq,
> + uint32_t guest_irq);
> +#else
> +static int kvm_arch_vfio_update_pi_irte(struct kvm *kvm, unsigned int
> host_irq,
> + uint32_t guest_irq)
> +{
> + return 0;
> +}
> +#endif
> +
> #ifdef CONFIG_HAVE_KVM_CPU_RELAX_INTERCEPT
>
> static inline void kvm_vcpu_set_in_spin_loop(struct kvm_vcpu *vcpu, bool val)
> diff --git a/virt/kvm/vfio.c b/virt/kvm/vfio.c
> index 6bc7001..5e5515f 100644
> --- a/virt/kvm/vfio.c
> +++ b/virt/kvm/vfio.c
> @@ -446,6 +446,99 @@ out:
> return ret;
> }
>
> +static int kvm_vfio_pci_get_irq_count(struct pci_dev *pdev, int irq_type)
> +{
> + if (irq_type == VFIO_PCI_INTX_IRQ_INDEX) {
> + u8 pin;
> +
> + pci_read_config_byte(pdev, PCI_INTERRUPT_PIN, &pin);
> + if (pin)
> + return 1;
> + } else if (irq_type == VFIO_PCI_MSI_IRQ_INDEX)
> + return pci_msi_vec_count(pdev);
> + else if (irq_type == VFIO_PCI_MSIX_IRQ_INDEX)
> + return pci_msix_vec_count(pdev);
> +
> + return 0;
> +}
for platform case I was asked to move the retrieval of absolute irq
number to the architecture specific part. I don't know if it should
apply to PCI stuff as well? This explains why I need to pass the VFIO
device (or struct device handle) to the arch specific part. Actually we
do the same job, we provide a phys/virt IRQ mapping to KVM, right? So to
me our architecture specific API should look quite similar?
> +
> +static int kvm_vfio_set_pi(struct kvm_device *kdev, int32_t __user *argp)
> +{
> + struct kvm_vfio_dev_irq pi_info;
> + uint32_t *gsi;
> + unsigned long minsz;
> + struct vfio_device *vdev;
> + struct msi_desc *entry;
> + struct device *dev;
> + struct pci_dev *pdev;
> + int i, max, ret;
> +
> + minsz = offsetofend(struct kvm_vfio_dev_irq, count);
> +
> + if (copy_from_user(&pi_info, (void __user *)argp, minsz))
> + return -EFAULT;
> +
> + if (pi_info.argsz < minsz || pi_info.index >= VFIO_PCI_NUM_IRQS)
PCI specific check, same remark as above but I will let Alex further
comment on this and possibly invalidate this commeny ;-)
> + return -EINVAL;
> +
> + vdev = kvm_vfio_get_vfio_device(pi_info.fd);
> + if (IS_ERR(vdev))
> + return PTR_ERR(vdev);
> +
> + dev = kvm_vfio_external_base_device(vdev);
> + if (!dev || !dev_is_pci(dev)) {
> + ret = -EFAULT;
> + goto put_vfio_device;
> + }
> +
> + pdev = to_pci_dev(dev);
> +
> + max = kvm_vfio_pci_get_irq_count(pdev, pi_info.index);
> + if (max <= 0) {
> + ret = -EFAULT;
> + goto put_vfio_device;
> + }
> +
> + if (pi_info.argsz - minsz < pi_info.count * sizeof(int) ||
shouldn' we use the actual datatype?
> + pi_info.start >= max || pi_info.start + pi_info.count > max) {
> + ret = -EINVAL;
> + goto put_vfio_device;
> + }
> +
> + gsi = memdup_user((void __user *)((unsigned long)argp + minsz),
> + pi_info.count * sizeof(int));
same question as above
> + if (IS_ERR(gsi)) {
> + ret = PTR_ERR(gsi);
> + goto put_vfio_device;
> + }
> +
> +#ifdef CONFIG_PCI_MSI
> + for (i = 0; i < pi_info.count; i++) {
> + list_for_each_entry(entry, &pdev->msi_list, list) {
> + if (entry->msi_attrib.entry_nr != pi_info.start+i)
> + continue;
> +
> + ret = kvm_arch_vfio_update_pi_irte(kdev->kvm,
> + entry->irq,
> + gsi[i]);
> + if (ret) {
> + ret = -EFAULT;
why -EFAULT? and not propagation of original error code?
you may have posting set for part of the subindexes and unset for rest.
Isn't it an issue?
Best Regards
Eric
> + goto free_gsi;
> + }
> + }
> + }
> +#endif
> +
> + ret = 0;
> +
> +free_gsi:
> + kfree(gsi);
> +
> +put_vfio_device:
> + kvm_vfio_put_vfio_device(vdev);
> + return ret;
> +}
> +
> static int kvm_vfio_set_device(struct kvm_device *kdev, long attr, u64 arg)
> {
> int32_t __user *argp = (int32_t __user *)(unsigned long)arg;
> @@ -456,6 +549,11 @@ static int kvm_vfio_set_device(struct kvm_device *kdev,
> long attr, u64 arg)
> case KVM_DEV_VFIO_DEVICE_UNFORWARD_IRQ:
> ret = kvm_vfio_control_irq_forward(kdev, attr, argp);
> break;
> +#ifdef __KVM_HAVE_ARCH_KVM_VFIO_POSTING
> + case KVM_DEV_VFIO_DEVICE_POSTING_IRQ:
> + ret = kvm_vfio_set_pi(kdev, argp);
> + break;
> +#endif
> default:
> ret = -ENXIO;
> }
> @@ -511,6 +609,11 @@ static int kvm_vfio_has_attr(struct kvm_device *dev,
> case KVM_DEV_VFIO_DEVICE_UNFORWARD_IRQ:
> return 0;
> #endif
> +#ifdef __KVM_HAVE_ARCH_KVM_VFIO_POSTING
> + case KVM_DEV_VFIO_DEVICE_POSTING_IRQ:
> + return 0;
> +#endif
> +
> }
> break;
> }
>
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