Hi Yi,
On 1/17/23 14:49, Yi Liu wrote:
> This defines KVM_DEV_VFIO_FILE* and make alias with KVM_DEV_VFIO_GROUP*.
> Old userspace uses KVM_DEV_VFIO_GROUP* works as well.
>
> Signed-off-by: Yi Liu <yi.l.liu@xxxxxxxxx>
> ---
> Documentation/virt/kvm/devices/vfio.rst | 32 ++++++++++++-------------
> include/uapi/linux/kvm.h | 23 +++++++++++++-----
> virt/kvm/vfio.c | 18 +++++++-------
> 3 files changed, 42 insertions(+), 31 deletions(-)
>
> diff --git a/Documentation/virt/kvm/devices/vfio.rst b/Documentation/virt/kvm/devices/vfio.rst
> index 2d20dc561069..ac4300ded398 100644
> --- a/Documentation/virt/kvm/devices/vfio.rst
> +++ b/Documentation/virt/kvm/devices/vfio.rst
> @@ -9,23 +9,23 @@ Device types supported:
> - KVM_DEV_TYPE_VFIO
>
> Only one VFIO instance may be created per VM. The created device
> -tracks VFIO groups in use by the VM and features of those groups
> -important to the correctness and acceleration of the VM. As groups
> -are enabled and disabled for use by the VM, KVM should be updated
> -about their presence. When registered with KVM, a reference to the
> -VFIO-group is held by KVM.
> -
> -Groups:
> - KVM_DEV_VFIO_GROUP
> -
> -KVM_DEV_VFIO_GROUP attributes:
> - KVM_DEV_VFIO_GROUP_ADD: Add a VFIO group to VFIO-KVM device tracking
> - kvm_device_attr.addr points to an int32_t file descriptor
> +tracks VFIO files (group or device) in use by the VM and features
> +of those groups/devices important to the correctness and acceleration
> +of the VM. As groups/device are enabled and disabled for use by the
> +VM, KVM should be updated about their presence. When registered with
> +KVM, a reference to the VFIO file is held by KVM.
> +
> +VFIO Files:
> + KVM_DEV_VFIO_FILE
> +
> +KVM_DEV_VFIO_FILE attributes:
> + KVM_DEV_VFIO_FILE_ADD: Add a VFIO file (group/device) to VFIO-KVM device
> + tracking kvm_device_attr.addr points to an int32_t file descriptor
> + for the VFIO file.
> + KVM_DEV_VFIO_FILE_DEL: Remove a VFIO file (group/device) from VFIO-KVM device
> + tracking kvm_device_attr.addr points to an int32_t file descriptor
> for the VFIO group.
> - KVM_DEV_VFIO_GROUP_DEL: Remove a VFIO group from VFIO-KVM device tracking
> - kvm_device_attr.addr points to an int32_t file descriptor
> - for the VFIO group.
> - KVM_DEV_VFIO_GROUP_SET_SPAPR_TCE: attaches a guest visible TCE table
> + KVM_DEV_VFIO_FILE_SET_SPAPR_TCE: attaches a guest visible TCE table
> allocated by sPAPR KVM.
> kvm_device_attr.addr points to a struct::
>
> diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
> index 55155e262646..ad36e144a41d 100644
> --- a/include/uapi/linux/kvm.h
> +++ b/include/uapi/linux/kvm.h
> @@ -1396,15 +1396,26 @@ struct kvm_create_device {
>
> struct kvm_device_attr {
> __u32 flags; /* no flags currently defined */
> - __u32 group; /* device-defined */
> - __u64 attr; /* group-defined */
> + union {
> + __u32 group;
> + __u32 file;
> + }; /* device-defined */
> + __u64 attr; /* VFIO-file-defined or group-defined */
I think there is a confusion here between the 'VFIO group' terminology
and the 'kvm device group' terminology. Commands for kvm devices are
gathered in groups and within groups you have sub-commands called
attributes.
See Documentation/virt/kvm/devices/arm-vgic-v3.rst for instance. So to
me this shall be left unchanged.
> __u64 addr; /* userspace address of attr data */
> };
>
> -#define KVM_DEV_VFIO_GROUP 1
> -#define KVM_DEV_VFIO_GROUP_ADD 1
> -#define KVM_DEV_VFIO_GROUP_DEL 2
> -#define KVM_DEV_VFIO_GROUP_SET_SPAPR_TCE 3
> +#define KVM_DEV_VFIO_FILE 1
> +
> +#define KVM_DEV_VFIO_FILE_ADD 1
> +#define KVM_DEV_VFIO_FILE_DEL 2
> +#define KVM_DEV_VFIO_FILE_SET_SPAPR_TCE 3
> +
> +/* Group aliases are for compile time uapi compatibility */
> +#define KVM_DEV_VFIO_GROUP KVM_DEV_VFIO_FILE
> +
> +#define KVM_DEV_VFIO_GROUP_ADD KVM_DEV_VFIO_FILE_ADD
> +#define KVM_DEV_VFIO_GROUP_DEL KVM_DEV_VFIO_FILE_DEL
> +#define KVM_DEV_VFIO_GROUP_SET_SPAPR_TCE KVM_DEV_VFIO_FILE_SET_SPAPR_TCE
>
> enum kvm_device_type {
> KVM_DEV_TYPE_FSL_MPIC_20 = 1,
> diff --git a/virt/kvm/vfio.c b/virt/kvm/vfio.c
> index 525efe37ab6d..e73ca60af3ae 100644
> --- a/virt/kvm/vfio.c
> +++ b/virt/kvm/vfio.c
> @@ -286,18 +286,18 @@ static int kvm_vfio_set_file(struct kvm_device *dev, long attr,
> int32_t fd;
>
> switch (attr) {
> - case KVM_DEV_VFIO_GROUP_ADD:
> + case KVM_DEV_VFIO_FILE_ADD:
> if (get_user(fd, argp))
> return -EFAULT;
> return kvm_vfio_file_add(dev, fd);
>
> - case KVM_DEV_VFIO_GROUP_DEL:
> + case KVM_DEV_VFIO_FILE_DEL:
> if (get_user(fd, argp))
> return -EFAULT;
> return kvm_vfio_file_del(dev, fd);
>
> #ifdef CONFIG_SPAPR_TCE_IOMMU
> - case KVM_DEV_VFIO_GROUP_SET_SPAPR_TCE:
> + case KVM_DEV_VFIO_FILE_SET_SPAPR_TCE:
> return kvm_vfio_file_set_spapr_tce(dev, arg);
> #endif
> }
> @@ -309,7 +309,7 @@ static int kvm_vfio_set_attr(struct kvm_device *dev,
> struct kvm_device_attr *attr)
> {
> switch (attr->group) {
> - case KVM_DEV_VFIO_GROUP:
> + case KVM_DEV_VFIO_FILE:
> return kvm_vfio_set_file(dev, attr->attr,
> u64_to_user_ptr(attr->addr));
> }
> @@ -320,13 +320,13 @@ static int kvm_vfio_set_attr(struct kvm_device *dev,
> static int kvm_vfio_has_attr(struct kvm_device *dev,
> struct kvm_device_attr *attr)
> {
> - switch (attr->group) {
> - case KVM_DEV_VFIO_GROUP:
> + switch (attr->file) {
> + case KVM_DEV_VFIO_FILE:
> switch (attr->attr) {
> - case KVM_DEV_VFIO_GROUP_ADD:
> - case KVM_DEV_VFIO_GROUP_DEL:
> + case KVM_DEV_VFIO_FILE_ADD:
> + case KVM_DEV_VFIO_FILE_DEL:
> #ifdef CONFIG_SPAPR_TCE_IOMMU
> - case KVM_DEV_VFIO_GROUP_SET_SPAPR_TCE:
> + case KVM_DEV_VFIO_FILE_SET_SPAPR_TCE:
> #endif
> return 0;
> }
Thanks
Eric
