On Tue, 4 Apr 2023 12:01:37 -0700
Brett Creeley <brett.creeley@xxxxxxx> wrote:
> The pds_core driver will supply adminq services, so find the PF
> and register with the DSC services.
>
> Use the following commands to enable a VF:
> echo 1 > /sys/bus/pci/drivers/pds_core/$PF_BDF/sriov_numvfs
>
> Signed-off-by: Brett Creeley <brett.creeley@xxxxxxx>
> Signed-off-by: Shannon Nelson <shannon.nelson@xxxxxxx>
> ---
> drivers/vfio/pci/pds/Makefile | 1 +
> drivers/vfio/pci/pds/cmds.c | 69 +++++++++++++++++++++++++++++++++
> drivers/vfio/pci/pds/cmds.h | 10 +++++
> drivers/vfio/pci/pds/pci_drv.c | 16 +++++++-
> drivers/vfio/pci/pds/pci_drv.h | 9 +++++
> drivers/vfio/pci/pds/vfio_dev.c | 5 +++
> drivers/vfio/pci/pds/vfio_dev.h | 2 +
> include/linux/pds/pds_lm.h | 12 ++++++
> 8 files changed, 123 insertions(+), 1 deletion(-)
> create mode 100644 drivers/vfio/pci/pds/cmds.c
> create mode 100644 drivers/vfio/pci/pds/cmds.h
> create mode 100644 drivers/vfio/pci/pds/pci_drv.h
> create mode 100644 include/linux/pds/pds_lm.h
>
> diff --git a/drivers/vfio/pci/pds/Makefile b/drivers/vfio/pci/pds/Makefile
> index e1a55ae0f079..87581111fa17 100644
> --- a/drivers/vfio/pci/pds/Makefile
> +++ b/drivers/vfio/pci/pds/Makefile
> @@ -4,5 +4,6 @@
> obj-$(CONFIG_PDS_VFIO_PCI) += pds_vfio.o
>
> pds_vfio-y := \
> + cmds.o \
> pci_drv.o \
> vfio_dev.o
> diff --git a/drivers/vfio/pci/pds/cmds.c b/drivers/vfio/pci/pds/cmds.c
> new file mode 100644
> index 000000000000..7807dbb2c72c
> --- /dev/null
> +++ b/drivers/vfio/pci/pds/cmds.c
> @@ -0,0 +1,69 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/* Copyright(c) 2023 Advanced Micro Devices, Inc. */
> +
> +#include <linux/io.h>
> +#include <linux/types.h>
> +
> +#include <linux/pds/pds_common.h>
> +#include <linux/pds/pds_core_if.h>
> +#include <linux/pds/pds_adminq.h>
> +#include <linux/pds/pds_lm.h>
> +
> +#include "vfio_dev.h"
> +#include "cmds.h"
> +
> +int
> +pds_vfio_register_client_cmd(struct pds_vfio_pci_device *pds_vfio)
> +{
> + union pds_core_adminq_comp comp = { 0 };
> + union pds_core_adminq_cmd cmd = { 0 };
> + struct device *dev;
> + int err;
> + u32 id;
> + u16 ci;
> +
> + id = PCI_DEVID(pds_vfio->pdev->bus->number,
> + pci_iov_virtfn_devfn(pds_vfio->pdev, pds_vfio->vf_id));
Does this actually work?
pds_vfio_pci_probe() is presumably called with a VF pdev because it
calls pdsc_get_pf_struct() -> pci_iov_get_pf_drvdata(), which returns
an error if !dev->is_virtfn. pds_vfio_init_device() also stores the
vf_id from pci_iov_vf_id(), which requires that it's called on a VF,
not PF. This same pdev gets stored at pds_vfio->pdev.
OTOH, pci_iov_virtfn_devfn() used here errors if !dev->is_physfn. So I
expect we're calling PCI_DEVID with the second arg as -EINVAL. The
first arg would also be suspicious if pds_vfio->pdev were the PF since
then we'd be making a PCI_DEVID combining the PF bus number and the VF
devfn.
We've also already stored the VF PCI_DEVID at pds_vfio->pci_id, so
creating it again seems entirely unnecessary.
Also, since we never check the return of pdsc_get_pf_struct() I'd guess
we take a segfault referencing off of pds_vfio->pdsc should the driver
bind to something other than expected. Validating the PF drvdata
before anything else seems like a good first stop in
pds_vfio_pci_probe().
It's also a little curious why we're storing the pdev at all in the
pds_vfio_pci_device when it's readily available from the embedded
vfio_pci_core_device. Thanks,
Alex
> +
> + dev = &pds_vfio->pdev->dev;
> + cmd.client_reg.opcode = PDS_AQ_CMD_CLIENT_REG;
> + snprintf(cmd.client_reg.devname, sizeof(cmd.client_reg.devname),
> + "%s.%d-%u", PDS_LM_DEV_NAME,
> + pci_domain_nr(pds_vfio->pdev->bus), id);
> +
> + err = pdsc_adminq_post(pds_vfio->pdsc, &cmd, &comp, false);
> + if (err) {
> + dev_info(dev, "register with DSC failed, status %d: %pe\n",
> + comp.status, ERR_PTR(err));
> + return err;
> + }
> +
> + ci = le16_to_cpu(comp.client_reg.client_id);
> + if (!ci) {
> + dev_err(dev, "%s: device returned null client_id\n", __func__);
> + return -EIO;
> + }
> + pds_vfio->client_id = ci;
> +
> + return 0;
> +}
> +
> +void
> +pds_vfio_unregister_client_cmd(struct pds_vfio_pci_device *pds_vfio)
> +{
> + union pds_core_adminq_comp comp = { 0 };
> + union pds_core_adminq_cmd cmd = { 0 };
> + struct device *dev;
> + int err;
> +
> + dev = &pds_vfio->pdev->dev;
> + cmd.client_unreg.opcode = PDS_AQ_CMD_CLIENT_UNREG;
> + cmd.client_unreg.client_id = cpu_to_le16(pds_vfio->client_id);
> +
> + err = pdsc_adminq_post(pds_vfio->pdsc, &cmd, &comp, false);
> + if (err)
> + dev_info(dev, "unregister from DSC failed, status %d: %pe\n",
> + comp.status, ERR_PTR(err));
> +
> + pds_vfio->client_id = 0;
> +}
> diff --git a/drivers/vfio/pci/pds/cmds.h b/drivers/vfio/pci/pds/cmds.h
> new file mode 100644
> index 000000000000..4c592afccf89
> --- /dev/null
> +++ b/drivers/vfio/pci/pds/cmds.h
> @@ -0,0 +1,10 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/* Copyright(c) 2023 Advanced Micro Devices, Inc. */
> +
> +#ifndef _CMDS_H_
> +#define _CMDS_H_
> +
> +int pds_vfio_register_client_cmd(struct pds_vfio_pci_device *pds_vfio);
> +void pds_vfio_unregister_client_cmd(struct pds_vfio_pci_device *pds_vfio);
> +
> +#endif /* _CMDS_H_ */
> diff --git a/drivers/vfio/pci/pds/pci_drv.c b/drivers/vfio/pci/pds/pci_drv.c
> index 5e554420792e..46537afdee2d 100644
> --- a/drivers/vfio/pci/pds/pci_drv.c
> +++ b/drivers/vfio/pci/pds/pci_drv.c
> @@ -8,9 +8,13 @@
> #include <linux/types.h>
> #include <linux/vfio.h>
>
> +#include <linux/pds/pds_common.h>
> #include <linux/pds/pds_core_if.h>
> +#include <linux/pds/pds_adminq.h>
>
> #include "vfio_dev.h"
> +#include "pci_drv.h"
> +#include "cmds.h"
>
> #define PDS_VFIO_DRV_NAME "pds_vfio"
> #define PDS_VFIO_DRV_DESCRIPTION "AMD/Pensando VFIO Device Driver"
> @@ -30,13 +34,23 @@ pds_vfio_pci_probe(struct pci_dev *pdev,
>
> dev_set_drvdata(&pdev->dev, &pds_vfio->vfio_coredev);
> pds_vfio->pdev = pdev;
> + pds_vfio->pdsc = pdsc_get_pf_struct(pdev);
> +
> + err = pds_vfio_register_client_cmd(pds_vfio);
> + if (err) {
> + dev_err(&pdev->dev, "failed to register as client: %pe\n",
> + ERR_PTR(err));
> + goto out_put_vdev;
> + }
>
> err = vfio_pci_core_register_device(&pds_vfio->vfio_coredev);
> if (err)
> - goto out_put_vdev;
> + goto out_unreg_client;
>
> return 0;
>
> +out_unreg_client:
> + pds_vfio_unregister_client_cmd(pds_vfio);
> out_put_vdev:
> vfio_put_device(&pds_vfio->vfio_coredev.vdev);
> return err;
> diff --git a/drivers/vfio/pci/pds/pci_drv.h b/drivers/vfio/pci/pds/pci_drv.h
> new file mode 100644
> index 000000000000..e79bed12ed14
> --- /dev/null
> +++ b/drivers/vfio/pci/pds/pci_drv.h
> @@ -0,0 +1,9 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/* Copyright(c) 2023 Advanced Micro Devices, Inc. */
> +
> +#ifndef _PCI_DRV_H
> +#define _PCI_DRV_H
> +
> +#include <linux/pci.h>
> +
> +#endif /* _PCI_DRV_H */
> diff --git a/drivers/vfio/pci/pds/vfio_dev.c b/drivers/vfio/pci/pds/vfio_dev.c
> index 0f70efec01e1..056715dea512 100644
> --- a/drivers/vfio/pci/pds/vfio_dev.c
> +++ b/drivers/vfio/pci/pds/vfio_dev.c
> @@ -31,6 +31,11 @@ pds_vfio_init_device(struct vfio_device *vdev)
> pds_vfio->vf_id = pci_iov_vf_id(pdev);
> pds_vfio->pci_id = PCI_DEVID(pdev->bus->number, pdev->devfn);
>
> + dev_dbg(&pdev->dev, "%s: PF %#04x VF %#04x (%d) vf_id %d domain %d pds_vfio %p\n",
> + __func__, pci_dev_id(pdev->physfn),
> + pds_vfio->pci_id, pds_vfio->pci_id, pds_vfio->vf_id,
> + pci_domain_nr(pdev->bus), pds_vfio);
> +
> return 0;
> }
>
> diff --git a/drivers/vfio/pci/pds/vfio_dev.h b/drivers/vfio/pci/pds/vfio_dev.h
> index a66f8069b88c..10557e8dc829 100644
> --- a/drivers/vfio/pci/pds/vfio_dev.h
> +++ b/drivers/vfio/pci/pds/vfio_dev.h
> @@ -10,9 +10,11 @@
> struct pds_vfio_pci_device {
> struct vfio_pci_core_device vfio_coredev;
> struct pci_dev *pdev;
> + void *pdsc;
>
> int vf_id;
> int pci_id;
> + u16 client_id;
> };
>
> const struct vfio_device_ops *pds_vfio_ops_info(void);
> diff --git a/include/linux/pds/pds_lm.h b/include/linux/pds/pds_lm.h
> new file mode 100644
> index 000000000000..2bc2bf79426e
> --- /dev/null
> +++ b/include/linux/pds/pds_lm.h
> @@ -0,0 +1,12 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/* Copyright(c) 2022 Pensando Systems, Inc */
> +
> +#ifndef _PDS_LM_H_
> +#define _PDS_LM_H_
> +
> +#include "pds_common.h"
> +
> +#define PDS_DEV_TYPE_LM_STR "LM"
> +#define PDS_LM_DEV_NAME PDS_CORE_DRV_NAME "." PDS_DEV_TYPE_LM_STR
> +
> +#endif /* _PDS_LM_H_ */
