Subject: RE: [RFC v2 1/4] hisi-acc-vfio-pci: add new vfio_pci driver for HiSilicon ACC devices



> -----Original Message-----
> From: Alex Williamson [mailto:[email protected]]
> Sent: 02 July 2021 21:29
> To: Shameerali Kolothum Thodi <[email protected]>
> Cc: [email protected]; [email protected];
> [email protected]; [email protected]; [email protected];
> Linuxarm <[email protected]>; liulongfang <[email protected]>;
> Zengtao (B) <[email protected]>; yuzenghui
> <[email protected]>; Jonathan Cameron
> <[email protected]>; Wangzhou (B) <[email protected]>
> Subject: Re: [RFC v2 1/4] hisi-acc-vfio-pci: add new vfio_pci driver for HiSilicon
> ACC devices
>
> On Fri, 2 Jul 2021 10:58:46 +0100
> Shameer Kolothum <[email protected]> wrote:
>
> > Add a vendor-specific vfio_pci driver for HiSilicon ACC devices.
> > This will be extended in follow-up patches to add support for
> > vfio live migration feature.
> >
> > Signed-off-by: Shameer Kolothum
> <[email protected]>
> > ---
> > drivers/vfio/pci/Kconfig | 9 +++
> > drivers/vfio/pci/Makefile | 2 +
> > drivers/vfio/pci/hisi_acc_vfio_pci.c | 100 +++++++++++++++++++++++++++
> > 3 files changed, 111 insertions(+)
> > create mode 100644 drivers/vfio/pci/hisi_acc_vfio_pci.c
> >
> > diff --git a/drivers/vfio/pci/Kconfig b/drivers/vfio/pci/Kconfig
> > index 9cdef46dd299..709807c28153 100644
> > --- a/drivers/vfio/pci/Kconfig
> > +++ b/drivers/vfio/pci/Kconfig
> > @@ -57,3 +57,12 @@ config MLX5_VFIO_PCI
> > framework.
> >
> > If you don't know what to do here, say N.
> > +
> > +config HISI_ACC_VFIO_PCI
> > + tristate "VFIO support for HiSilicon ACC devices"
> > + depends on ARM64 && VFIO_PCI_CORE
> > + help
> > + This provides generic PCI support for HiSilicon devices using the VFIO
> > + framework.
> > +
> > + If you don't know what to do here, say N.
> > diff --git a/drivers/vfio/pci/Makefile b/drivers/vfio/pci/Makefile
> > index a0df9c2a4bd9..d1de3e81921f 100644
> > --- a/drivers/vfio/pci/Makefile
> > +++ b/drivers/vfio/pci/Makefile
> > @@ -3,6 +3,7 @@
> > obj-$(CONFIG_VFIO_PCI_CORE) += vfio-pci-core.o
> > obj-$(CONFIG_VFIO_PCI) += vfio-pci.o
> > obj-$(CONFIG_MLX5_VFIO_PCI) += mlx5-vfio-pci.o
> > +obj-$(CONFIG_HISI_ACC_VFIO_PCI) += hisi-acc-vfio-pci.o
> >
> > vfio-pci-core-y := vfio_pci_core.o vfio_pci_intrs.o vfio_pci_rdwr.o
> vfio_pci_config.o
> > vfio-pci-core-$(CONFIG_S390) += vfio_pci_zdev.o
> > @@ -11,3 +12,4 @@ vfio-pci-y := vfio_pci.o
> > vfio-pci-$(CONFIG_VFIO_PCI_IGD) += vfio_pci_igd.o
> >
> > mlx5-vfio-pci-y := mlx5_vfio_pci.o
> > +hisi-acc-vfio-pci-y := hisi_acc_vfio_pci.o
> > diff --git a/drivers/vfio/pci/hisi_acc_vfio_pci.c
> b/drivers/vfio/pci/hisi_acc_vfio_pci.c
> > new file mode 100644
> > index 000000000000..a9e173098ab5
> > --- /dev/null
> > +++ b/drivers/vfio/pci/hisi_acc_vfio_pci.c
> > @@ -0,0 +1,100 @@
> > +// SPDX-License-Identifier: GPL-2.0-only
> > +/*
> > + * Copyright (c) 2021, HiSilicon Ltd.
> > + */
> > +
> > +#include <linux/device.h>
> > +#include <linux/eventfd.h>
> > +#include <linux/file.h>
> > +#include <linux/interrupt.h>
> > +#include <linux/module.h>
> > +#include <linux/pci.h>
> > +#include <linux/vfio.h>
> > +#include <linux/vfio_pci_core.h>
> > +
> > +static int hisi_acc_vfio_pci_open(struct vfio_device *core_vdev)
> > +{
> > + struct vfio_pci_core_device *vdev =
> > + container_of(core_vdev, struct vfio_pci_core_device, vdev);
> > + int ret;
> > +
> > + lockdep_assert_held(&core_vdev->reflck->lock);
> > +
> > + ret = vfio_pci_core_enable(vdev);
> > + if (ret)
> > + return ret;
> > +
> > + vfio_pci_core_finish_enable(vdev);
> > +
> > + return 0;
> > +}
> > +
> > +static const struct vfio_device_ops hisi_acc_vfio_pci_ops = {
> > + .name = "hisi-acc-vfio-pci",
> > + .open = hisi_acc_vfio_pci_open,
> > + .release = vfio_pci_core_release,
> > + .ioctl = vfio_pci_core_ioctl,
> > + .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,
> > + .reflck_attach = vfio_pci_core_reflck_attach,
> > +};
> > +
> > +static int hisi_acc_vfio_pci_probe(struct pci_dev *pdev, const struct
> pci_device_id *id)
> > +{
> > + struct vfio_pci_core_device *vdev;
> > + int ret;
> > +
> > + vdev = kzalloc(sizeof(*vdev), GFP_KERNEL);
> > + if (!vdev)
> > + return -ENOMEM;
> > +
> > + ret = vfio_pci_core_register_device(vdev, pdev, &hisi_acc_vfio_pci_ops);
> > + if (ret)
> > + goto out_free;
> > +
> > + dev_set_drvdata(&pdev->dev, vdev);
> > +
> > + return 0;
> > +
> > +out_free:
> > + kfree(vdev);
> > + return ret;
> > +}
> > +
> > +static void hisi_acc_vfio_pci_remove(struct pci_dev *pdev)
> > +{
> > + struct vfio_pci_core_device *vdev = dev_get_drvdata(&pdev->dev);
> > +
> > + vfio_pci_core_unregister_device(vdev);
> > + kfree(vdev);
> > +}
> > +
> > +static const struct pci_device_id hisi_acc_vfio_pci_table[] = {
> > + { PCI_DRIVER_OVERRIDE_DEVICE_VFIO(PCI_VENDOR_ID_HUAWEI,
> 0xa256) }, /* SEC VF */
> > + { PCI_DRIVER_OVERRIDE_DEVICE_VFIO(PCI_VENDOR_ID_HUAWEI,
> 0xa259) }, /* HPRE VF */
> > + { PCI_DRIVER_OVERRIDE_DEVICE_VFIO(PCI_VENDOR_ID_HUAWEI,
> 0xa251) }, /* ZIP VF */
> > + { 0, }
> > +};
> > +
> > +MODULE_DEVICE_TABLE(pci, hisi_acc_vfio_pci_table);
> > +
> > +static struct pci_driver hisi_acc_vfio_pci_driver = {
> > + .name = "hisi-acc-vfio-pci",
> > + .id_table = hisi_acc_vfio_pci_table,
> > + .probe = hisi_acc_vfio_pci_probe,
> > + .remove = hisi_acc_vfio_pci_remove,
> > +#ifdef CONFIG_PCI_IOV
> > + .sriov_configure = vfio_pci_core_sriov_configure,
> > +#endif
>
> The device table suggests only VFs are supported by this driver, so it
> really shouldn't need sriov_configure support, right? Thanks,

Right. Only VFs are supported. I will remove this.

Thanks,
Shameer

>
> Alex
>
> > + .err_handler = &vfio_pci_core_err_handlers,
> > +};
> > +
> > +module_pci_driver(hisi_acc_vfio_pci_driver);
> > +
> > +MODULE_LICENSE("GPL v2");
> > +MODULE_AUTHOR("Liu Longfang <[email protected]>");
> > +MODULE_AUTHOR("Shameer Kolothum
> <[email protected]>");
> > +MODULE_DESCRIPTION("HiSilicon VFIO PCI - Generic VFIO PCI driver for
> HiSilicon ACC device family");