Messages in this thread | | | Subject | Re: [RFC PATCH 2/2] mdev: introduce device specific ops | From | Jason Wang <> | Date | Tue, 17 Sep 2019 18:16:46 +0800 |
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On 2019/9/17 下午4:09, Tian, Kevin wrote: >> From: Jason Wang >> Sent: Thursday, September 12, 2019 5:40 PM >> >> Currently, except for the crate and remove. The rest fields of >> mdev_parent_ops is just designed for vfio-mdev driver and may not help >> for kernel mdev driver. So follow the device id support by previous >> patch, this patch introduces device specific ops which points to >> device specific ops (e.g vfio ops). This allows the future drivers >> like virtio-mdev to implement its own device specific ops. > Can you give an example about what ops might be required to support > kernel mdev driver? I know you posted a link earlier, but putting a small > example here can save time and avoid inconsistent understanding. Then > it will help whether the proposed split makes sense or there is a > possibility of redefining the callbacks to meet the both requirements. > imo those callbacks fulfill some basic requirements when mediating > a device...
I put it in the cover letter.
The link is https://lkml.org/lkml/2019/9/10/135 which abuses the current VFIO based mdev parent ops.
Thanks
>> Signed-off-by: Jason Wang <jasowang@redhat.com> >> --- >> drivers/gpu/drm/i915/gvt/kvmgt.c | 14 +++--- >> drivers/s390/cio/vfio_ccw_ops.c | 14 +++--- >> drivers/s390/crypto/vfio_ap_ops.c | 10 +++-- >> drivers/vfio/mdev/vfio_mdev.c | 30 +++++++------ >> include/linux/mdev.h | 72 ++++++++++++++++++------------- >> samples/vfio-mdev/mbochs.c | 16 ++++--- >> samples/vfio-mdev/mdpy.c | 16 ++++--- >> samples/vfio-mdev/mtty.c | 14 +++--- >> 8 files changed, 113 insertions(+), 73 deletions(-) >> >> diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c >> b/drivers/gpu/drm/i915/gvt/kvmgt.c >> index 19d51a35f019..64823998fd58 100644 >> --- a/drivers/gpu/drm/i915/gvt/kvmgt.c >> +++ b/drivers/gpu/drm/i915/gvt/kvmgt.c >> @@ -1600,20 +1600,22 @@ static const struct attribute_group >> *intel_vgpu_groups[] = { >> NULL, >> }; >> >> -static struct mdev_parent_ops intel_vgpu_ops = { >> - .mdev_attr_groups = intel_vgpu_groups, >> - .create = intel_vgpu_create, >> - .remove = intel_vgpu_remove, >> - >> +static struct vfio_mdev_parent_ops intel_vfio_vgpu_ops = { >> .open = intel_vgpu_open, >> .release = intel_vgpu_release, >> - >> .read = intel_vgpu_read, >> .write = intel_vgpu_write, >> .mmap = intel_vgpu_mmap, >> .ioctl = intel_vgpu_ioctl, >> }; >> >> +static struct mdev_parent_ops intel_vgpu_ops = { >> + .mdev_attr_groups = intel_vgpu_groups, >> + .create = intel_vgpu_create, >> + .remove = intel_vgpu_remove, >> + .device_ops = &intel_vfio_vgpu_ops, >> +}; >> + >> static int kvmgt_host_init(struct device *dev, void *gvt, const void *ops) >> { >> struct attribute **kvm_type_attrs; >> diff --git a/drivers/s390/cio/vfio_ccw_ops.c >> b/drivers/s390/cio/vfio_ccw_ops.c >> index f87d9409e290..96e9f18100ae 100644 >> --- a/drivers/s390/cio/vfio_ccw_ops.c >> +++ b/drivers/s390/cio/vfio_ccw_ops.c >> @@ -564,11 +564,7 @@ static ssize_t vfio_ccw_mdev_ioctl(struct >> mdev_device *mdev, >> } >> } >> >> -static const struct mdev_parent_ops vfio_ccw_mdev_ops = { >> - .owner = THIS_MODULE, >> - .supported_type_groups = mdev_type_groups, >> - .create = vfio_ccw_mdev_create, >> - .remove = vfio_ccw_mdev_remove, >> +static const struct vfio_mdev_parent_ops vfio_mdev_ops = { >> .open = vfio_ccw_mdev_open, >> .release = vfio_ccw_mdev_release, >> .read = vfio_ccw_mdev_read, >> @@ -576,6 +572,14 @@ static const struct mdev_parent_ops >> vfio_ccw_mdev_ops = { >> .ioctl = vfio_ccw_mdev_ioctl, >> }; >> >> +static const struct mdev_parent_ops vfio_ccw_mdev_ops = { >> + .owner = THIS_MODULE, >> + .supported_type_groups = mdev_type_groups, >> + .create = vfio_ccw_mdev_create, >> + .remove = vfio_ccw_mdev_remove, >> + .device_ops = &vfio_mdev_ops, >> +}; >> + >> int vfio_ccw_mdev_reg(struct subchannel *sch) >> { >> return mdev_register_vfio_device(&sch->dev, >> &vfio_ccw_mdev_ops); >> diff --git a/drivers/s390/crypto/vfio_ap_ops.c >> b/drivers/s390/crypto/vfio_ap_ops.c >> index eacbde3c7a97..a48282bff066 100644 >> --- a/drivers/s390/crypto/vfio_ap_ops.c >> +++ b/drivers/s390/crypto/vfio_ap_ops.c >> @@ -1280,15 +1280,19 @@ static ssize_t vfio_ap_mdev_ioctl(struct >> mdev_device *mdev, >> return ret; >> } >> >> +static const struct vfio_mdev_parent_ops vfio_mdev_ops = { >> + .open = vfio_ap_mdev_open, >> + .release = vfio_ap_mdev_release, >> + .ioctl = vfio_ap_mdev_ioctl, >> +}; >> + >> static const struct mdev_parent_ops vfio_ap_matrix_ops = { >> .owner = THIS_MODULE, >> .supported_type_groups = vfio_ap_mdev_type_groups, >> .mdev_attr_groups = vfio_ap_mdev_attr_groups, >> .create = vfio_ap_mdev_create, >> .remove = vfio_ap_mdev_remove, >> - .open = vfio_ap_mdev_open, >> - .release = vfio_ap_mdev_release, >> - .ioctl = vfio_ap_mdev_ioctl, >> + .device_ops = &vfio_mdev_ops, >> }; >> >> int vfio_ap_mdev_register(void) >> diff --git a/drivers/vfio/mdev/vfio_mdev.c >> b/drivers/vfio/mdev/vfio_mdev.c >> index 887c57f10880..1196fbb6c3d2 100644 >> --- a/drivers/vfio/mdev/vfio_mdev.c >> +++ b/drivers/vfio/mdev/vfio_mdev.c >> @@ -25,15 +25,16 @@ static int vfio_mdev_open(void *device_data) >> { >> struct mdev_device *mdev = device_data; >> struct mdev_parent *parent = mdev->parent; >> + const struct vfio_mdev_parent_ops *ops = parent->ops- >>> device_ops; >> int ret; >> >> - if (unlikely(!parent->ops->open)) >> + if (unlikely(!ops->open)) >> return -EINVAL; >> >> if (!try_module_get(THIS_MODULE)) >> return -ENODEV; >> >> - ret = parent->ops->open(mdev); >> + ret = ops->open(mdev); >> if (ret) >> module_put(THIS_MODULE); >> >> @@ -44,9 +45,10 @@ static void vfio_mdev_release(void *device_data) >> { >> struct mdev_device *mdev = device_data; >> struct mdev_parent *parent = mdev->parent; >> + const struct vfio_mdev_parent_ops *ops = parent->ops- >>> device_ops; >> - if (likely(parent->ops->release)) >> - parent->ops->release(mdev); >> + if (likely(ops->release)) >> + ops->release(mdev); >> >> module_put(THIS_MODULE); >> } >> @@ -56,11 +58,12 @@ static long vfio_mdev_unlocked_ioctl(void >> *device_data, >> { >> struct mdev_device *mdev = device_data; >> struct mdev_parent *parent = mdev->parent; >> + const struct vfio_mdev_parent_ops *ops = parent->ops- >>> device_ops; >> - if (unlikely(!parent->ops->ioctl)) >> + if (unlikely(!ops->ioctl)) >> return -EINVAL; >> >> - return parent->ops->ioctl(mdev, cmd, arg); >> + return ops->ioctl(mdev, cmd, arg); >> } >> >> static ssize_t vfio_mdev_read(void *device_data, char __user *buf, >> @@ -68,11 +71,12 @@ static ssize_t vfio_mdev_read(void *device_data, >> char __user *buf, >> { >> struct mdev_device *mdev = device_data; >> struct mdev_parent *parent = mdev->parent; >> + const struct vfio_mdev_parent_ops *ops = parent->ops- >>> device_ops; >> - if (unlikely(!parent->ops->read)) >> + if (unlikely(!ops->read)) >> return -EINVAL; >> >> - return parent->ops->read(mdev, buf, count, ppos); >> + return ops->read(mdev, buf, count, ppos); >> } >> >> static ssize_t vfio_mdev_write(void *device_data, const char __user *buf, >> @@ -80,22 +84,24 @@ static ssize_t vfio_mdev_write(void *device_data, >> const char __user *buf, >> { >> struct mdev_device *mdev = device_data; >> struct mdev_parent *parent = mdev->parent; >> + const struct vfio_mdev_parent_ops *ops = parent->ops- >>> device_ops; >> - if (unlikely(!parent->ops->write)) >> + if (unlikely(!ops->write)) >> return -EINVAL; >> >> - return parent->ops->write(mdev, buf, count, ppos); >> + return ops->write(mdev, buf, count, ppos); >> } >> >> static int vfio_mdev_mmap(void *device_data, struct vm_area_struct >> *vma) >> { >> struct mdev_device *mdev = device_data; >> struct mdev_parent *parent = mdev->parent; >> + const struct vfio_mdev_parent_ops *ops = parent->ops- >>> device_ops; >> - if (unlikely(!parent->ops->mmap)) >> + if (unlikely(!ops->mmap)) >> return -EINVAL; >> >> - return parent->ops->mmap(mdev, vma); >> + return ops->mmap(mdev, vma); >> } >> >> static const struct vfio_device_ops vfio_mdev_dev_ops = { >> diff --git a/include/linux/mdev.h b/include/linux/mdev.h >> index f85045392120..3b8a76bc69cf 100644 >> --- a/include/linux/mdev.h >> +++ b/include/linux/mdev.h >> @@ -27,27 +27,9 @@ int mdev_set_iommu_device(struct device *dev, >> struct device *iommu_device); >> struct device *mdev_get_iommu_device(struct device *dev); >> >> /** >> - * struct mdev_parent_ops - Structure to be registered for each parent >> device to >> - * register the device to mdev module. >> + * struct vfio_mdev_parent_ops - Structure to be registered for each >> + * parent device to register the device to vfio-mdev module. >> * >> - * @owner: The module owner. >> - * @dev_attr_groups: Attributes of the parent device. >> - * @mdev_attr_groups: Attributes of the mediated device. >> - * @supported_type_groups: Attributes to define supported types. It is >> mandatory >> - * to provide supported types. >> - * @create: Called to allocate basic resources in parent device's >> - * driver for a particular mediated device. It is >> - * mandatory to provide create ops. >> - * @kobj: kobject of type for which 'create' is called. >> - * @mdev: mdev_device structure on of mediated >> device >> - * that is being created >> - * Returns integer: success (0) or error (< 0) >> - * @remove: Called to free resources in parent device's driver for >> a >> - * a mediated device. It is mandatory to provide >> 'remove' >> - * ops. >> - * @mdev: mdev_device device structure which is >> being >> - * destroyed >> - * Returns integer: success (0) or error (< 0) >> * @open: Open mediated device. >> * @mdev: mediated device. >> * Returns integer: success (0) or error (< 0) >> @@ -72,6 +54,43 @@ struct device *mdev_get_iommu_device(struct >> device *dev); >> * @mmap: mmap callback >> * @mdev: mediated device structure >> * @vma: vma structure >> + */ >> +struct vfio_mdev_parent_ops { >> + int (*open)(struct mdev_device *mdev); >> + void (*release)(struct mdev_device *mdev); >> + ssize_t (*read)(struct mdev_device *mdev, char __user *buf, >> + size_t count, loff_t *ppos); >> + ssize_t (*write)(struct mdev_device *mdev, const char __user *buf, >> + size_t count, loff_t *ppos); >> + long (*ioctl)(struct mdev_device *mdev, unsigned int cmd, >> + unsigned long arg); >> + int (*mmap)(struct mdev_device *mdev, struct vm_area_struct >> *vma); >> +}; >> + >> +/** >> + * struct mdev_parent_ops - Structure to be registered for each parent >> device to >> + * register the device to mdev module. >> + * >> + * @owner: The module owner. >> + * @dev_attr_groups: Attributes of the parent device. >> + * @mdev_attr_groups: Attributes of the mediated device. >> + * @supported_type_groups: Attributes to define supported types. It is >> mandatory >> + * to provide supported types. >> + * @create: Called to allocate basic resources in parent device's >> + * driver for a particular mediated device. It is >> + * mandatory to provide create ops. >> + * @kobj: kobject of type for which 'create' is called. >> + * @mdev: mdev_device structure on of mediated >> device >> + * that is being created >> + * Returns integer: success (0) or error (< 0) >> + * @remove: Called to free resources in parent device's driver for >> a >> + * a mediated device. It is mandatory to provide >> 'remove' >> + * ops. >> + * @mdev: mdev_device device structure which is >> being >> + * destroyed >> + * Returns integer: success (0) or error (< 0) >> + * @device_ops: Device specific emulation callback. >> + * >> * Parent device that support mediated device should be registered with >> mdev >> * module with mdev_parent_ops structure. >> **/ >> @@ -83,15 +102,7 @@ struct mdev_parent_ops { >> >> int (*create)(struct kobject *kobj, struct mdev_device *mdev); >> int (*remove)(struct mdev_device *mdev); >> - int (*open)(struct mdev_device *mdev); >> - void (*release)(struct mdev_device *mdev); >> - ssize_t (*read)(struct mdev_device *mdev, char __user *buf, >> - size_t count, loff_t *ppos); >> - ssize_t (*write)(struct mdev_device *mdev, const char __user *buf, >> - size_t count, loff_t *ppos); >> - long (*ioctl)(struct mdev_device *mdev, unsigned int cmd, >> - unsigned long arg); >> - int (*mmap)(struct mdev_device *mdev, struct vm_area_struct >> *vma); >> + const void *device_ops; >> }; >> >> /* interface for exporting mdev supported type attributes */ >> @@ -137,7 +148,8 @@ const guid_t *mdev_uuid(struct mdev_device >> *mdev); >> >> extern struct bus_type mdev_bus_type; >> >> -int mdev_register_vfio_device(struct device *dev, const struct >> mdev_parent_ops *ops); >> +int mdev_register_vfio_device(struct device *dev, >> + const struct mdev_parent_ops *ops); >> void mdev_unregister_device(struct device *dev); >> >> int mdev_register_driver(struct mdev_driver *drv, struct module *owner); >> diff --git a/samples/vfio-mdev/mbochs.c b/samples/vfio-mdev/mbochs.c >> index 71a4469be85d..53ceb357f152 100644 >> --- a/samples/vfio-mdev/mbochs.c >> +++ b/samples/vfio-mdev/mbochs.c >> @@ -1418,12 +1418,7 @@ static struct attribute_group >> *mdev_type_groups[] = { >> NULL, >> }; >> >> -static const struct mdev_parent_ops mdev_fops = { >> - .owner = THIS_MODULE, >> - .mdev_attr_groups = mdev_dev_groups, >> - .supported_type_groups = mdev_type_groups, >> - .create = mbochs_create, >> - .remove = mbochs_remove, >> +static const struct vfio_mdev_parent_ops vfio_mdev_ops = { >> .open = mbochs_open, >> .release = mbochs_close, >> .read = mbochs_read, >> @@ -1432,6 +1427,15 @@ static const struct mdev_parent_ops mdev_fops >> = { >> .mmap = mbochs_mmap, >> }; >> >> +static const struct mdev_parent_ops mdev_fops = { >> + .owner = THIS_MODULE, >> + .mdev_attr_groups = mdev_dev_groups, >> + .supported_type_groups = mdev_type_groups, >> + .create = mbochs_create, >> + .remove = mbochs_remove, >> + .device_ops = &vfio_mdev_ops, >> +}; >> + >> static const struct file_operations vd_fops = { >> .owner = THIS_MODULE, >> }; >> diff --git a/samples/vfio-mdev/mdpy.c b/samples/vfio-mdev/mdpy.c >> index d3029dd27d91..4ba285a5768f 100644 >> --- a/samples/vfio-mdev/mdpy.c >> +++ b/samples/vfio-mdev/mdpy.c >> @@ -725,12 +725,7 @@ static struct attribute_group *mdev_type_groups[] >> = { >> NULL, >> }; >> >> -static const struct mdev_parent_ops mdev_fops = { >> - .owner = THIS_MODULE, >> - .mdev_attr_groups = mdev_dev_groups, >> - .supported_type_groups = mdev_type_groups, >> - .create = mdpy_create, >> - .remove = mdpy_remove, >> +static const struct vfio_mdev_parent_ops vfio_mdev_ops = { >> .open = mdpy_open, >> .release = mdpy_close, >> .read = mdpy_read, >> @@ -739,6 +734,15 @@ static const struct mdev_parent_ops mdev_fops = >> { >> .mmap = mdpy_mmap, >> }; >> >> +static const struct mdev_parent_ops mdev_fops = { >> + .owner = THIS_MODULE, >> + .mdev_attr_groups = mdev_dev_groups, >> + .supported_type_groups = mdev_type_groups, >> + .create = mdpy_create, >> + .remove = mdpy_remove, >> + .device_ops = &vfio_mdev_ops, >> +}; >> + >> static const struct file_operations vd_fops = { >> .owner = THIS_MODULE, >> }; >> diff --git a/samples/vfio-mdev/mtty.c b/samples/vfio-mdev/mtty.c >> index 744c88a6b22c..a468904ec626 100644 >> --- a/samples/vfio-mdev/mtty.c >> +++ b/samples/vfio-mdev/mtty.c >> @@ -1410,6 +1410,14 @@ static struct attribute_group >> *mdev_type_groups[] = { >> NULL, >> }; >> >> +static const struct vfio_mdev_parent_ops vfio_mdev_ops = { >> + .open = mtty_open, >> + .release = mtty_close, >> + .read = mtty_read, >> + .write = mtty_write, >> + .ioctl = mtty_ioctl, >> +}; >> + >> static const struct mdev_parent_ops mdev_fops = { >> .owner = THIS_MODULE, >> .dev_attr_groups = mtty_dev_groups, >> @@ -1417,11 +1425,7 @@ static const struct mdev_parent_ops mdev_fops >> = { >> .supported_type_groups = mdev_type_groups, >> .create = mtty_create, >> .remove = mtty_remove, >> - .open = mtty_open, >> - .release = mtty_close, >> - .read = mtty_read, >> - .write = mtty_write, >> - .ioctl = mtty_ioctl, >> + .device_ops = &vfio_mdev_ops, >> }; >> >> static void mtty_device_release(struct device *dev) >> -- >> 2.19.1 >> >> _______________________________________________ >> Virtualization mailing list >> Virtualization@lists.linux-foundation.org >> https://lists.linuxfoundation.org/mailman/listinfo/virtualization
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