2022-01-14 23:06:30

by Matthew Rosato

Subject: [PATCH v2 28/30] vfio-pci/zdev: add DTSM to clp group capability

The DTSM, or designation type supported mask, indicates what IOAT formats
are available to the guest. For an interpreted device, userspace will not
know what format(s) the IOAT assist supports, so pass it via the
capability chain. Since the value belongs to the Query PCI Function Group
clp, let's extend the existing capability with a new version.

Signed-off-by: Matthew Rosato <[email protected]>
---
drivers/vfio/pci/vfio_pci_zdev.c | 9 ++++++---
include/uapi/linux/vfio_zdev.h | 3 +++
2 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/drivers/vfio/pci/vfio_pci_zdev.c b/drivers/vfio/pci/vfio_pci_zdev.c
index 2b169d688937..aa2ef9067c7d 100644
--- a/drivers/vfio/pci/vfio_pci_zdev.c
+++ b/drivers/vfio/pci/vfio_pci_zdev.c
@@ -45,19 +45,22 @@ static int zpci_group_cap(struct zpci_dev *zdev, struct vfio_info_cap *caps)
{
struct vfio_device_info_cap_zpci_group cap = {
.header.id = VFIO_DEVICE_INFO_CAP_ZPCI_GROUP,
- .header.version = 1,
+ .header.version = 2,
.dasm = zdev->dma_mask,
.msi_addr = zdev->msi_addr,
.flags = VFIO_DEVICE_INFO_ZPCI_FLAG_REFRESH,
.mui = zdev->fmb_update,
.noi = zdev->max_msi,
.maxstbl = ZPCI_MAX_WRITE_SIZE,
- .version = zdev->version
+ .version = zdev->version,
+ .dtsm = 0
};

/* Some values are different for interpreted devices */
- if (zdev->kzdev && zdev->kzdev->interp)
+ if (zdev->kzdev && zdev->kzdev->interp) {
cap.maxstbl = zdev->maxstbl;
+ cap.dtsm = kvm_s390_pci_get_dtsm(zdev);
+ }

return vfio_info_add_capability(caps, &cap.header, sizeof(cap));
}
diff --git a/include/uapi/linux/vfio_zdev.h b/include/uapi/linux/vfio_zdev.h
index 1a5229b7bb18..b4c2ba8e71f0 100644
--- a/include/uapi/linux/vfio_zdev.h
+++ b/include/uapi/linux/vfio_zdev.h
@@ -47,6 +47,9 @@ struct vfio_device_info_cap_zpci_group {
__u16 noi; /* Maximum number of MSIs */
__u16 maxstbl; /* Maximum Store Block Length */
__u8 version; /* Supported PCI Version */
+ /* End of version 1 */
+ __u8 dtsm; /* Supported IOAT Designations */
+ /* End of version 2 */
};

/**
--
2.27.0

2022-01-21 19:17:17

by Pierre Morel

Subject: Re: [PATCH v2 28/30] vfio-pci/zdev: add DTSM to clp group capability

On 1/14/22 21:31, Matthew Rosato wrote:
> The DTSM, or designation type supported mask, indicates what IOAT formats
> are available to the guest. For an interpreted device, userspace will not
> know what format(s) the IOAT assist supports, so pass it via the
> capability chain. Since the value belongs to the Query PCI Function Group
> clp, let's extend the existing capability with a new version.
>
> Signed-off-by: Matthew Rosato <[email protected]>

Reviewed-by: Pierre Morel <[email protected]>



> ---
> drivers/vfio/pci/vfio_pci_zdev.c | 9 ++++++---
> include/uapi/linux/vfio_zdev.h | 3 +++
> 2 files changed, 9 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/vfio/pci/vfio_pci_zdev.c b/drivers/vfio/pci/vfio_pci_zdev.c
> index 2b169d688937..aa2ef9067c7d 100644
> --- a/drivers/vfio/pci/vfio_pci_zdev.c
> +++ b/drivers/vfio/pci/vfio_pci_zdev.c
> @@ -45,19 +45,22 @@ static int zpci_group_cap(struct zpci_dev *zdev, struct vfio_info_cap *caps)
> {
> struct vfio_device_info_cap_zpci_group cap = {
> .header.id = VFIO_DEVICE_INFO_CAP_ZPCI_GROUP,
> - .header.version = 1,
> + .header.version = 2,
> .dasm = zdev->dma_mask,
> .msi_addr = zdev->msi_addr,
> .flags = VFIO_DEVICE_INFO_ZPCI_FLAG_REFRESH,
> .mui = zdev->fmb_update,
> .noi = zdev->max_msi,
> .maxstbl = ZPCI_MAX_WRITE_SIZE,
> - .version = zdev->version
> + .version = zdev->version,
> + .dtsm = 0
> };
>
> /* Some values are different for interpreted devices */
> - if (zdev->kzdev && zdev->kzdev->interp)
> + if (zdev->kzdev && zdev->kzdev->interp) {
> cap.maxstbl = zdev->maxstbl;
> + cap.dtsm = kvm_s390_pci_get_dtsm(zdev);
> + }
>
> return vfio_info_add_capability(caps, &cap.header, sizeof(cap));
> }
> diff --git a/include/uapi/linux/vfio_zdev.h b/include/uapi/linux/vfio_zdev.h
> index 1a5229b7bb18..b4c2ba8e71f0 100644
> --- a/include/uapi/linux/vfio_zdev.h
> +++ b/include/uapi/linux/vfio_zdev.h
> @@ -47,6 +47,9 @@ struct vfio_device_info_cap_zpci_group {
> __u16 noi; /* Maximum number of MSIs */
> __u16 maxstbl; /* Maximum Store Block Length */
> __u8 version; /* Supported PCI Version */
> + /* End of version 1 */
> + __u8 dtsm; /* Supported IOAT Designations */
> + /* End of version 2 */
> };
>
> /**
>

--
Pierre Morel
IBM Lab Boeblingen