Re: [RFC PATCH v2 vfio 1/7] vfio/pds: Initial support for pds_vfio VFIO driver

liulongfang
2023-01-03T12:12:23Z

On 2022/12/15 7:21, Brett Creeley wrote:
> This is the initial framework for the new pds_vfio device driver. This
> does the very basics of registering the PCI device 1dd8:1006 and
> configuring as a VFIO PCI device.
>
> With this change, the VF device can be bound to the pds_vfio driver on
> the host and presented to the VM as an NVMe VF.
>
> Signed-off-by: Brett Creeley <brett.creeley@amd.com>
> Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
> ---
> drivers/vfio/pci/pds/Makefile | 6 ++
> drivers/vfio/pci/pds/pci_drv.c | 102 ++++++++++++++++++++++++++++++++
> drivers/vfio/pci/pds/vfio_dev.c | 74 +++++++++++++++++++++++
> drivers/vfio/pci/pds/vfio_dev.h | 23 +++++++
> include/linux/pds/pds_core_if.h | 1 +
> 5 files changed, 206 insertions(+)
> create mode 100644 drivers/vfio/pci/pds/Makefile
> create mode 100644 drivers/vfio/pci/pds/pci_drv.c
> create mode 100644 drivers/vfio/pci/pds/vfio_dev.c
> create mode 100644 drivers/vfio/pci/pds/vfio_dev.h
>
> diff --git a/drivers/vfio/pci/pds/Makefile b/drivers/vfio/pci/pds/Makefile
> new file mode 100644
> index 000000000000..dcc8f6beffe2
> --- /dev/null
> +++ b/drivers/vfio/pci/pds/Makefile
> @@ -0,0 +1,6 @@
> +# SPDX-License-Identifier: GPL-2.0
> +obj-$(CONFIG_PDS_VFIO_PCI) += pds_vfio.o
> +
> +pds_vfio-y := \
> + pci_drv.o \
> + vfio_dev.o
> diff --git a/drivers/vfio/pci/pds/pci_drv.c b/drivers/vfio/pci/pds/pci_drv.c
> new file mode 100644
> index 000000000000..09cab0dbb0e9
> --- /dev/null
> +++ b/drivers/vfio/pci/pds/pci_drv.c
> @@ -0,0 +1,102 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/* Copyright(c) 2022 Pensando Systems, Inc */
> +
> +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
> +
> +#include <linux/module.h>
> +#include <linux/pci.h>
> +#include <linux/types.h>
> +#include <linux/vfio.h>
> +
> +#include <linux/pds/pds_core_if.h>
> +
> +#include "vfio_dev.h"
> +
> +#define PDS_VFIO_DRV_NAME "pds_vfio"
> +#define PDS_VFIO_DRV_DESCRIPTION "Pensando VFIO Device Driver"
> +#define PCI_VENDOR_ID_PENSANDO 0x1dd8
> +
> +static int
> +pds_vfio_pci_probe(struct pci_dev *pdev,
> + const struct pci_device_id *id)
> +{
> + struct pds_vfio_pci_device *pds_vfio;
> + int err;
> +
> + pds_vfio = vfio_alloc_device(pds_vfio_pci_device, vfio_coredev.vdev,
> + &pdev->dev, pds_vfio_ops_info());
> + if (IS_ERR(pds_vfio))
> + return PTR_ERR(pds_vfio);
> +
> + dev_set_drvdata(&pdev->dev, &pds_vfio->vfio_coredev);
> + pds_vfio->pdev = pdev;
> +
> + err = vfio_pci_core_register_device(&pds_vfio->vfio_coredev);
> + if (err)
> + goto out_put_vdev;
> +
> + return 0;
> +
> +out_put_vdev:
> + vfio_put_device(&pds_vfio->vfio_coredev.vdev);
> + return err;
> +}
> +
> +static void
> +pds_vfio_pci_remove(struct pci_dev *pdev)
> +{
> + struct pds_vfio_pci_device *pds_vfio = pds_vfio_pci_drvdata(pdev);
> +
> + vfio_pci_core_unregister_device(&pds_vfio->vfio_coredev);
> + vfio_put_device(&pds_vfio->vfio_coredev.vdev);
> +}
> +
> +static const struct pci_device_id
> +pds_vfio_pci_table[] = {
> + {
> + .class = PCI_CLASS_STORAGE_EXPRESS,
> + .class_mask = 0xffffff,
> + .vendor = PCI_VENDOR_ID_PENSANDO,
> + .device = PCI_DEVICE_ID_PENSANDO_NVME_VF,
> + .subvendor = PCI_ANY_ID,
> + .subdevice = PCI_ANY_ID,
> + .override_only = PCI_ID_F_VFIO_DRIVER_OVERRIDE,
> + },
> + { 0, }
> +};
> +MODULE_DEVICE_TABLE(pci, pds_vfio_pci_table);
> +
> +static struct pci_driver
> +pds_vfio_pci_driver = {
> + .name = PDS_VFIO_DRV_NAME,
> + .id_table = pds_vfio_pci_table,
> + .probe = pds_vfio_pci_probe,
> + .remove = pds_vfio_pci_remove,
> + .driver_managed_dma = true,
> +};
> +
> +static void __exit
> +pds_vfio_pci_cleanup(void)
> +{
> + pci_unregister_driver(&pds_vfio_pci_driver);
> +}
> +module_exit(pds_vfio_pci_cleanup);
> +
> +static int __init
> +pds_vfio_pci_init(void)
> +{
> + int err;
> +
> + err = pci_register_driver(&pds_vfio_pci_driver);
> + if (err) {
> + pr_err("pci driver register failed: %pe\n", ERR_PTR(err));
> + return err;
> + }
> +
> + return 0;
> +}
> +module_init(pds_vfio_pci_init);

It would be better to use module_pci_driver(pds_vfio_pci_driver) instead

Thanks,
Longfang.

> +
> +MODULE_DESCRIPTION(PDS_VFIO_DRV_DESCRIPTION);
> +MODULE_AUTHOR("Pensando Systems, Inc");
> +MODULE_LICENSE("GPL");
> diff --git a/drivers/vfio/pci/pds/vfio_dev.c b/drivers/vfio/pci/pds/vfio_dev.c
> new file mode 100644
> index 000000000000..f8f4006c0915
> --- /dev/null
> +++ b/drivers/vfio/pci/pds/vfio_dev.c
> @@ -0,0 +1,74 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/* Copyright(c) 2022 Pensando Systems, Inc */
> +
> +#include <linux/vfio.h>
> +#include <linux/vfio_pci_core.h>
> +
> +#include "vfio_dev.h"
> +
> +struct pds_vfio_pci_device *
> +pds_vfio_pci_drvdata(struct pci_dev *pdev)
> +{
> + struct vfio_pci_core_device *core_device = dev_get_drvdata(&pdev->dev);
> +
> + return container_of(core_device, struct pds_vfio_pci_device,
> + vfio_coredev);
> +}
> +
> +static int
> +pds_vfio_init_device(struct vfio_device *vdev)
> +{
> + struct pds_vfio_pci_device *pds_vfio =
> + container_of(vdev, struct pds_vfio_pci_device,
> + vfio_coredev.vdev);
> + struct pci_dev *pdev = to_pci_dev(vdev->dev);
> + int err;
> +
> + err = vfio_pci_core_init_dev(vdev);
> + if (err)
> + return err;
> +
> + pds_vfio->vf_id = pci_iov_vf_id(pdev);
> + pds_vfio->pci_id = PCI_DEVID(pdev->bus->number, pdev->devfn);
> +
> + return 0;
> +}
> +
> +static int
> +pds_vfio_open_device(struct vfio_device *vdev)
> +{
> + struct pds_vfio_pci_device *pds_vfio =
> + container_of(vdev, struct pds_vfio_pci_device,
> + vfio_coredev.vdev);
> + int err;
> +
> + err = vfio_pci_core_enable(&pds_vfio->vfio_coredev);
> + if (err)
> + return err;
> +
> + vfio_pci_core_finish_enable(&pds_vfio->vfio_coredev);
> +
> + return 0;
> +}
> +
> +static const struct vfio_device_ops
> +pds_vfio_ops = {
> + .name = "pds-vfio",
> + .init = pds_vfio_init_device,
> + .release = vfio_pci_core_release_dev,
> + .open_device = pds_vfio_open_device,
> + .close_device = vfio_pci_core_close_device,
> + .ioctl = vfio_pci_core_ioctl,
> + .device_feature = vfio_pci_core_ioctl_feature,
> + .read = vfio_pci_core_read,
> + .write = vfio_pci_core_write,
> + .mmap = vfio_pci_core_mmap,
> + .request = vfio_pci_core_request,
> + .match = vfio_pci_core_match,
> +};
> +
> +const struct vfio_device_ops *
> +pds_vfio_ops_info(void)
> +{
> + return &pds_vfio_ops;
> +}
> diff --git a/drivers/vfio/pci/pds/vfio_dev.h b/drivers/vfio/pci/pds/vfio_dev.h
> new file mode 100644
> index 000000000000..289479a08dce
> --- /dev/null
> +++ b/drivers/vfio/pci/pds/vfio_dev.h
> @@ -0,0 +1,23 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/* Copyright(c) 2022 Pensando Systems, Inc */
> +
> +#ifndef _VFIO_DEV_H_
> +#define _VFIO_DEV_H_
> +
> +#include <linux/pci.h>
> +#include <linux/vfio_pci_core.h>
> +
> +struct pds_vfio_pci_device {
> + struct vfio_pci_core_device vfio_coredev;
> + struct pci_dev *pdev;
> +
> + int vf_id;
> + int pci_id;
> +};
> +
> +const struct vfio_device_ops *
> +pds_vfio_ops_info(void);
> +struct pds_vfio_pci_device *
> +pds_vfio_pci_drvdata(struct pci_dev *pdev);
> +
> +#endif /* _VFIO_DEV_H_ */
> diff --git a/include/linux/pds/pds_core_if.h b/include/linux/pds/pds_core_if.h
> index 6e92697657e4..4362b94a7666 100644
> --- a/include/linux/pds/pds_core_if.h
> +++ b/include/linux/pds/pds_core_if.h
> @@ -9,6 +9,7 @@
> #define PCI_VENDOR_ID_PENSANDO 0x1dd8
> #define PCI_DEVICE_ID_PENSANDO_CORE_PF 0x100c
> #define PCI_DEVICE_ID_PENSANDO_VDPA_VF 0x100b
> +#define PCI_DEVICE_ID_PENSANDO_NVME_VF 0x1006
>
> #define PDS_CORE_BARS_MAX 4
> #define PDS_CORE_PCI_BAR_DBELL 1
>