lkml.org 
[lkml]   [2022]   [Jan]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH v2 26/30] vfio-pci/zdev: wire up zPCI adapter interrupt forwarding support
    Date
    Introduce support for VFIO_DEVICE_FEATURE_ZPCI_AIF, which is a new
    VFIO_DEVICE_FEATURE ioctl. This interface is used to indicate that an
    s390x vfio-pci device wishes to enable/disable zPCI adapter interrupt
    forwarding, which allows underlying firmware to deliver interrupts
    directly to the associated kvm guest.

    Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
    ---
    arch/s390/include/asm/kvm_pci.h | 2 +
    drivers/vfio/pci/vfio_pci_core.c | 2 +
    drivers/vfio/pci/vfio_pci_zdev.c | 98 +++++++++++++++++++++++++++++++-
    include/linux/vfio_pci_core.h | 10 ++++
    include/uapi/linux/vfio.h | 7 +++
    include/uapi/linux/vfio_zdev.h | 20 +++++++
    6 files changed, 138 insertions(+), 1 deletion(-)

    diff --git a/arch/s390/include/asm/kvm_pci.h b/arch/s390/include/asm/kvm_pci.h
    index dc00c3f27a00..dbab349a4a75 100644
    --- a/arch/s390/include/asm/kvm_pci.h
    +++ b/arch/s390/include/asm/kvm_pci.h
    @@ -36,6 +36,8 @@ struct kvm_zdev {
    struct zpci_fib fib;
    struct notifier_block nb;
    bool interp;
    + bool aif;
    + bool fhost;
    };

    int kvm_s390_pci_dev_open(struct zpci_dev *zdev);
    diff --git a/drivers/vfio/pci/vfio_pci_core.c b/drivers/vfio/pci/vfio_pci_core.c
    index 2b2d64a2190c..01658de660bd 100644
    --- a/drivers/vfio/pci/vfio_pci_core.c
    +++ b/drivers/vfio/pci/vfio_pci_core.c
    @@ -1174,6 +1174,8 @@ long vfio_pci_core_ioctl(struct vfio_device *core_vdev, unsigned int cmd,
    return 0;
    case VFIO_DEVICE_FEATURE_ZPCI_INTERP:
    return vfio_pci_zdev_feat_interp(vdev, feature, arg);
    + case VFIO_DEVICE_FEATURE_ZPCI_AIF:
    + return vfio_pci_zdev_feat_aif(vdev, feature, arg);
    default:
    return -ENOTTY;
    }
    diff --git a/drivers/vfio/pci/vfio_pci_zdev.c b/drivers/vfio/pci/vfio_pci_zdev.c
    index 4339f48b98bc..891cfa016d63 100644
    --- a/drivers/vfio/pci/vfio_pci_zdev.c
    +++ b/drivers/vfio/pci/vfio_pci_zdev.c
    @@ -13,6 +13,7 @@
    #include <linux/vfio_zdev.h>
    #include <asm/pci_clp.h>
    #include <asm/pci_io.h>
    +#include <asm/pci_insn.h>
    #include <asm/kvm_pci.h>

    #include <linux/vfio_pci_core.h>
    @@ -208,6 +209,99 @@ int vfio_pci_zdev_feat_interp(struct vfio_pci_core_device *vdev,
    return rc;
    }

    +int vfio_pci_zdev_feat_aif(struct vfio_pci_core_device *vdev,
    + struct vfio_device_feature feature,
    + unsigned long arg)
    +{
    + struct zpci_dev *zdev = to_zpci(vdev->pdev);
    + struct vfio_device_zpci_aif *data;
    + struct vfio_device_feature *feat;
    + unsigned long minsz;
    + int size, rc = 0;
    +
    + if (!zdev || !zdev->kzdev)
    + return -EINVAL;
    +
    + /* If PROBE specified, return probe results immediately */
    + if (feature.flags & VFIO_DEVICE_FEATURE_PROBE)
    + return kvm_s390_pci_aif_probe(zdev);
    +
    + /* GET and SET are mutually exclusive */
    + if ((feature.flags & VFIO_DEVICE_FEATURE_GET) &&
    + (feature.flags & VFIO_DEVICE_FEATURE_SET))
    + return -EINVAL;
    +
    + size = sizeof(*feat) + sizeof(*data);
    + feat = kzalloc(size, GFP_KERNEL);
    + if (!feat)
    + return -ENOMEM;
    +
    + data = (struct vfio_device_zpci_aif *)&feat->data;
    + minsz = offsetofend(struct vfio_device_feature, flags);
    +
    + if (feature.argsz < minsz + sizeof(*data))
    + return -EINVAL;
    +
    + /* Get the rest of the payload for GET/SET */
    + rc = copy_from_user(data, (void __user *)(arg + minsz),
    + sizeof(*data));
    + if (rc)
    + rc = -EINVAL;
    +
    + if (feature.flags & VFIO_DEVICE_FEATURE_GET) {
    + if (zdev->kzdev->aif)
    + data->flags = VFIO_DEVICE_ZPCI_FLAG_AIF_FLOAT;
    + if (zdev->kzdev->fhost)
    + data->flags |= VFIO_DEVICE_ZPCI_FLAG_AIF_HOST;
    +
    + if (copy_to_user((void __user *)arg, feat, size))
    + rc = -EFAULT;
    + } else if (feature.flags & VFIO_DEVICE_FEATURE_SET) {
    + if (data->flags & VFIO_DEVICE_ZPCI_FLAG_AIF_FLOAT) {
    + /* create a guest fib */
    + struct zpci_fib fib;
    +
    + fib.fmt0.aibv = data->ibv;
    + fib.fmt0.isc = data->isc;
    + fib.fmt0.noi = data->noi;
    + if (data->sb != 0) {
    + fib.fmt0.aisb = data->sb;
    + fib.fmt0.aisbo = data->sbo;
    + fib.fmt0.sum = 1;
    + } else {
    + fib.fmt0.aisb = 0;
    + fib.fmt0.aisbo = 0;
    + fib.fmt0.sum = 0;
    + }
    + if (data->flags & VFIO_DEVICE_ZPCI_FLAG_AIF_HOST) {
    + rc = kvm_s390_pci_aif_enable(zdev, &fib, false);
    + if (!rc) {
    + zdev->kzdev->aif = true;
    + zdev->kzdev->fhost = true;
    + }
    + } else {
    + rc = kvm_s390_pci_aif_enable(zdev, &fib, true);
    + if (!rc)
    + zdev->kzdev->aif = true;
    + }
    + } else if (data->flags == 0) {
    + rc = kvm_s390_pci_aif_disable(zdev);
    + if (!rc) {
    + zdev->kzdev->aif = false;
    + zdev->kzdev->fhost = false;
    + }
    + } else {
    + rc = -EINVAL;
    + }
    + } else {
    + /* Neither GET nor SET were specified */
    + rc = -EINVAL;
    + }
    +
    + kfree(feat);
    + return rc;
    +}
    +
    static int vfio_pci_zdev_group_notifier(struct notifier_block *nb,
    unsigned long action, void *data)
    {
    @@ -255,8 +349,10 @@ void vfio_pci_zdev_release(struct vfio_pci_core_device *vdev)
    * If the device was using interpretation, don't trust that userspace
    * did the appropriate cleanup
    */
    - if (zdev->gd != 0)
    + if (zdev->gd != 0) {
    + kvm_s390_pci_aif_disable(zdev);
    kvm_s390_pci_interp_disable(zdev);
    + }

    kvm_s390_pci_dev_release(zdev);
    }
    diff --git a/include/linux/vfio_pci_core.h b/include/linux/vfio_pci_core.h
    index 0db2b1051931..7ec5e82e7933 100644
    --- a/include/linux/vfio_pci_core.h
    +++ b/include/linux/vfio_pci_core.h
    @@ -201,6 +201,9 @@ extern int vfio_pci_info_zdev_add_caps(struct vfio_pci_core_device *vdev,
    int vfio_pci_zdev_feat_interp(struct vfio_pci_core_device *vdev,
    struct vfio_device_feature feature,
    unsigned long arg);
    +int vfio_pci_zdev_feat_aif(struct vfio_pci_core_device *vdev,
    + struct vfio_device_feature feature,
    + unsigned long arg);
    void vfio_pci_zdev_open(struct vfio_pci_core_device *vdev);
    void vfio_pci_zdev_release(struct vfio_pci_core_device *vdev);
    #else
    @@ -217,6 +220,13 @@ static inline int vfio_pci_zdev_feat_interp(struct vfio_pci_core_device *vdev,
    return -ENOTTY;
    }

    +static inline int vfio_pci_zdev_feat_aif(struct vfio_pci_core_device *vdev,
    + struct vfio_device_feature feature,
    + unsigned long arg)
    +{
    + return -ENOTTY;
    +}
    +
    static inline void vfio_pci_zdev_open(struct vfio_pci_core_device *vdev)
    {
    }
    diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h
    index b9a75485b8e7..fe3bfd99bf50 100644
    --- a/include/uapi/linux/vfio.h
    +++ b/include/uapi/linux/vfio.h
    @@ -1009,6 +1009,13 @@ struct vfio_device_feature {
    */
    #define VFIO_DEVICE_FEATURE_ZPCI_INTERP (1)

    +/*
    + * Provide support for enbaling adapter interruption forwarding for zPCI
    + * devices. This feature is only valid for s390x PCI devices. Data provided
    + * when setting and getting this feature is further described in vfio_zdev.h
    + */
    +#define VFIO_DEVICE_FEATURE_ZPCI_AIF (2)
    +
    /* -------- API for Type1 VFIO IOMMU -------- */

    /**
    diff --git a/include/uapi/linux/vfio_zdev.h b/include/uapi/linux/vfio_zdev.h
    index 575f0410dc66..c574e23f9385 100644
    --- a/include/uapi/linux/vfio_zdev.h
    +++ b/include/uapi/linux/vfio_zdev.h
    @@ -90,4 +90,24 @@ struct vfio_device_zpci_interp {
    __u32 fh; /* Host device function handle */
    };

    +/**
    + * VFIO_DEVICE_FEATURE_ZPCI_AIF
    + *
    + * This feature is used for enabling forwarding of adapter interrupts directly
    + * from firmware to the guest. When setting this feature, the flags indicate
    + * whether to enable/disable the feature and the structure defined below is
    + * used to setup the forwarding structures. When getting this feature, only
    + * the flags are used to indicate the current state.
    + */
    +struct vfio_device_zpci_aif {
    + __u64 flags;
    +#define VFIO_DEVICE_ZPCI_FLAG_AIF_FLOAT 1
    +#define VFIO_DEVICE_ZPCI_FLAG_AIF_HOST 2
    + __u64 ibv; /* Address of guest interrupt bit vector */
    + __u64 sb; /* Address of guest summary bit */
    + __u32 noi; /* Number of interrupts */
    + __u8 isc; /* Guest interrupt subclass */
    + __u8 sbo; /* Offset of guest summary bit vector */
    +};
    +
    #endif
    --
    2.27.0
    \
     
     \ /
      Last update: 2022-01-14 21:34    [W:4.188 / U:0.132 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site