On Thu, 23 May 2019 14:25:26 +0200
Pierre Morel <pmorel@xxxxxxxxxxxxx> wrote:
> We define a new configuration entry for VFIO/PCI, VFIO_PCI_ZDEV
>
> When the VFIO_PCI_ZDEV feature is configured we initialize
> a new device region, VFIO_REGION_SUBTYPE_ZDEV_CLP, to hold
> the information from the ZPCI device the userland needs to
> give to a guest driving the zPCI function.
>
> Signed-off-by: Pierre Morel <pmorel@xxxxxxxxxxxxx>
> ---
> drivers/vfio/pci/Kconfig | 7 ++++
> drivers/vfio/pci/Makefile | 1 +
> drivers/vfio/pci/vfio_pci.c | 9 ++++
> drivers/vfio/pci/vfio_pci_private.h | 10 +++++
> drivers/vfio/pci/vfio_pci_zdev.c | 83 +++++++++++++++++++++++++++++++++++++
> 5 files changed, 110 insertions(+)
> create mode 100644 drivers/vfio/pci/vfio_pci_zdev.c
>
> diff --git a/drivers/vfio/pci/Kconfig b/drivers/vfio/pci/Kconfig
> index d0f8e4f..9c1181c 100644
> --- a/drivers/vfio/pci/Kconfig
> +++ b/drivers/vfio/pci/Kconfig
> @@ -44,3 +44,10 @@ config VFIO_PCI_NVLINK2
> depends on VFIO_PCI && PPC_POWERNV
> help
> VFIO PCI support for P9 Witherspoon machine with NVIDIA V100 GPUs
> +
> +config VFIO_PCI_ZDEV
> + tristate "VFIO PCI Generic for ZPCI devices"
Shouldn't this be 'bool'?
> + depends on VFIO_PCI && S390
> + default y
> + help
> + VFIO PCI support for S390 Z-PCI devices
> diff --git a/drivers/vfio/pci/Makefile b/drivers/vfio/pci/Makefile
> index 9662c06..fd53819 100644
> --- a/drivers/vfio/pci/Makefile
> +++ b/drivers/vfio/pci/Makefile
> @@ -2,5 +2,6 @@
> vfio-pci-y := vfio_pci.o vfio_pci_intrs.o vfio_pci_rdwr.o vfio_pci_config.o
> vfio-pci-$(CONFIG_VFIO_PCI_IGD) += vfio_pci_igd.o
> vfio-pci-$(CONFIG_VFIO_PCI_NVLINK2) += vfio_pci_nvlink2.o
> +vfio-pci-$(CONFIG_VFIO_PCI_ZDEV) += vfio_pci_zdev.o
>
> obj-$(CONFIG_VFIO_PCI) += vfio-pci.o
> diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c
> index 3fa20e9..b6087d6 100644
> --- a/drivers/vfio/pci/vfio_pci.c
> +++ b/drivers/vfio/pci/vfio_pci.c
> @@ -362,6 +362,15 @@ static int vfio_pci_enable(struct vfio_pci_device *vdev)
> }
> }
>
> + if (IS_ENABLED(CONFIG_VFIO_PCI_ZDEV)) {
> + ret = vfio_pci_zdev_init(vdev);
> + if (ret) {
> + dev_warn(&vdev->pdev->dev,
> + "Failed to setup ZDEV regions\n");
> + goto disable_exit;
> + }
> + }
> +
> vfio_pci_probe_mmaps(vdev);
>
> return 0;
> diff --git a/drivers/vfio/pci/vfio_pci_private.h b/drivers/vfio/pci/vfio_pci_private.h
> index 1812cf2..db73cdf 100644
> --- a/drivers/vfio/pci/vfio_pci_private.h
> +++ b/drivers/vfio/pci/vfio_pci_private.h
> @@ -189,4 +189,14 @@ static inline int vfio_pci_ibm_npu2_init(struct vfio_pci_device *vdev)
> return -ENODEV;
> }
> #endif
> +
> +#ifdef(IS_ENABLED_VFIO_PCI_ZDEV)
I thought this might be some clever new macro, but is it just a typo?
Seems it should just be
#ifdef CONFIG_VFIO_PCI_ZDEV
> +extern int vfio_pci_zdev_init(struct vfio_pci_device *vdev);
> +#else
> +static inline int vfio_pci_zdev_init(struct vfio_pci_device *vdev)
> +{
> + return -ENODEV;
> +}
> +#endif
> +
> #endif /* VFIO_PCI_PRIVATE_H */
> diff --git a/drivers/vfio/pci/vfio_pci_zdev.c b/drivers/vfio/pci/vfio_pci_zdev.c
> new file mode 100644
> index 0000000..230a4e4
> --- /dev/null
> +++ b/drivers/vfio/pci/vfio_pci_zdev.c
> @@ -0,0 +1,83 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * VFIO ZPCI devices support
> + *
> + * Copyright (C) IBM Corp. 2019. All rights reserved.
> + * Author: Pierre Morel <pmorel@xxxxxxxxxxxxx>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + */
> +#include <linux/io.h>
> +#include <linux/pci.h>
> +#include <linux/uaccess.h>
> +#include <linux/vfio.h>
> +#include <linux/vfio_zdev.h>
> +
> +#include "vfio_pci_private.h"
> +
> +static size_t vfio_pci_zdev_rw(struct vfio_pci_device *vdev,
> + char __user *buf, size_t count, loff_t *ppos,
> + bool iswrite)
> +{
> + struct vfio_region_zpci_info *region;
> + struct zpci_dev *zdev;
> + unsigned int index = VFIO_PCI_OFFSET_TO_INDEX(*ppos);
> +
> + if (!vdev->pdev->bus)
> + return -ENODEV;
> +
> + zdev = vdev->pdev->bus->sysdata;
> + if (!zdev)
> + return -ENODEV;
> +
> + if ((*ppos & VFIO_PCI_OFFSET_MASK) || (count != sizeof(*region)))
> + return -EINVAL;
Why? This sort of restriction would need to be documented in the ABI.
> +
> + region = vdev->region[index - VFIO_PCI_NUM_REGIONS].data;
> + region->dasm = zdev->dma_mask;
> + region->start_dma = zdev->start_dma;
> + region->end_dma = zdev->end_dma;
> + region->msi_addr = zdev->msi_addr;
> + region->flags = VFIO_PCI_ZDEV_FLAGS_REFRESH;
> + region->gid = zdev->pfgid;
> + region->mui = zdev->fmb_update;
> + region->noi = zdev->max_msi;
> + memcpy(region->util_str, zdev->util_str, CLP_UTIL_STR_LEN);
Does anything here change? Why not do this in the init function?
> + if (copy_to_user(buf, region, count))
> + return -EFAULT;
It's really not that difficult to make this support arbitrary reads.
> +
> + return count;
> +}
> +
> +static void vfio_pci_zdev_release(struct vfio_pci_device *vdev,
> + struct vfio_pci_region *region)
> +{
> + kfree(region->data);
> +}
> +
> +static const struct vfio_pci_regops vfio_pci_zdev_regops = {
> + .rw = vfio_pci_zdev_rw,
> + .release = vfio_pci_zdev_release,
> +};
> +
> +int vfio_pci_zdev_init(struct vfio_pci_device *vdev)
> +{
> + struct vfio_region_zpci_info *region;
> + int ret;
> +
> + region = kmalloc(sizeof(*region), GFP_KERNEL);
> + if (!region)
> + return -ENOMEM;
> +
> + ret = vfio_pci_register_dev_region(vdev,
> + PCI_VENDOR_ID_IBM | VFIO_REGION_TYPE_PCI_VENDOR_TYPE,
The uapi should specify 0x1014 as the vendor ID to eliminate any
confusion.
> + VFIO_REGION_SUBTYPE_ZDEV_CLP,
> + &vfio_pci_zdev_regops, sizeof(*region),
'sizeof(*region) + CLP_UTIL_STR_LEN' if suggestion in previous patch is
used.
> + VFIO_REGION_INFO_FLAG_READ, region);
This FLAG_READ only tells the user what is supported, it's up to your
.rw callback to reject iswrite.
> +
> + return ret;
> +}
