On Wed, Sep 25, 2019 at 08:45:21PM +0800, Jason Wang wrote: > > On 2019/9/25 下午5:09, Tian, Kevin wrote: > > > From: Jason Wang [mailto:jasowang@xxxxxxxxxx] > > > Sent: Tuesday, September 24, 2019 9:54 PM > > > > > > This patch implements basic support for mdev driver that supports > > > virtio transport for kernel virtio driver. > > > > > > Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx> > > > --- > > > include/linux/mdev.h | 2 + > > > include/linux/virtio_mdev.h | 145 > > > ++++++++++++++++++++++++++++++++++++ > > > 2 files changed, 147 insertions(+) > > > create mode 100644 include/linux/virtio_mdev.h > > > > > > diff --git a/include/linux/mdev.h b/include/linux/mdev.h > > > index 3414307311f1..73ac27b3b868 100644 > > > --- a/include/linux/mdev.h > > > +++ b/include/linux/mdev.h > > > @@ -126,6 +126,8 @@ struct mdev_device *mdev_from_dev(struct device > > > *dev); > > > > > > enum { > > > MDEV_ID_VFIO = 1, > > > + MDEV_ID_VIRTIO = 2, > > > + MDEV_ID_VHOST = 3, > > > /* New entries must be added here */ > > > }; > > > > > > diff --git a/include/linux/virtio_mdev.h b/include/linux/virtio_mdev.h > > > new file mode 100644 > > > index 000000000000..d1a40a739266 > > > --- /dev/null > > > +++ b/include/linux/virtio_mdev.h > > > @@ -0,0 +1,145 @@ > > > +/* SPDX-License-Identifier: GPL-2.0-only */ > > > +/* > > > + * Virtio mediated device driver > > > + * > > > + * Copyright 2019, Red Hat Corp. > > > + * Author: Jason Wang <jasowang@xxxxxxxxxx> > > > + */ > > > +#ifndef _LINUX_VIRTIO_MDEV_H > > > +#define _LINUX_VIRTIO_MDEV_H > > > + > > > +#include <linux/interrupt.h> > > > +#include <linux/mdev.h> > > > +#include <uapi/linux/vhost.h> > > > + > > > +#define VIRTIO_MDEV_DEVICE_API_STRING "virtio-mdev" > > > +#define VIRTIO_MDEV_VERSION 0x1 > > Just be curious. is this version identical to virtio spec version that below > > callbacks are created for, or just irrelevant? > > > It could be a hint but basically it's a way for userspace driver > compatibility. For kernel we don't need this. > > > > > > > + > > > +struct virtio_mdev_callback { > > > + irqreturn_t (*callback)(void *data); > > > + void *private; > > > +}; > > > + > > > +/** > > > + * struct vfio_mdev_device_ops - Structure to be registered for each > > > + * mdev device to register the device to virtio-mdev module. > > > + * > > > + * @set_vq_address: Set the address of virtqueue > > > + * @mdev: mediated device > > > + * @idx: virtqueue index > > > + * @desc_area: address of desc area > > > + * @driver_area: address of driver area > > > + * @device_area: address of device area > > > + * Returns integer: success (0) or error (< 0) > > > + * @set_vq_num: Set the size of virtqueue > > > + * @mdev: mediated device > > > + * @idx: virtqueue index > > > + * @num: the size of virtqueue > > > + * @kick_vq: Kick the virtqueue > > > + * @mdev: mediated device > > > + * @idx: virtqueue index > > > + * @set_vq_cb: Set the interrut calback function for > > > + * a virtqueue > > > + * @mdev: mediated device > > > + * @idx: virtqueue index > > > + * @cb: virtio-mdev interrupt callback > > > structure > > > + * @set_vq_ready: Set ready status for a virtqueue > > > + * @mdev: mediated device > > > + * @idx: virtqueue index > > > + * @ready: ready (true) not ready(false) > > > + * @get_vq_ready: Get ready status for a virtqueue > > > + * @mdev: mediated device > > > + * @idx: virtqueue index > > > + * Returns boolean: ready (true) or not (false) > > > + * @set_vq_state: Set the state for a virtqueue > > > + * @mdev: mediated device > > > + * @idx: virtqueue index > > > + * @state: virtqueue state (last_avail_idx) > > > + * Returns integer: success (0) or error (< 0) > > > + * @get_vq_state: Get the state for a virtqueue > > > + * @mdev: mediated device > > > + * @idx: virtqueue index > > > + * Returns virtqueue state (last_avail_idx) > > > + * @get_vq_align: Get the virtqueue align requirement > > > + * for the device > > > + * @mdev: mediated device > > > + * Returns virtqueue algin requirement > > > + * @get_features: Get virtio features supported by the device > > > + * @mdev: mediated device > > > + * Returns the features support by the > > > + * device > > > + * @get_features: Set virtio features supported by the driver > > > + * @mdev: mediated device > > > + * @features: feature support by the driver > > > + * Returns integer: success (0) or error (< 0) > > > + * @set_config_cb: Set the config interrupt callback > > > + * @mdev: mediated device > > > + * @cb: virtio-mdev interrupt callback > > > structure > > > + * @get_device_id: Get virtio device id > > > + * @mdev: mediated device > > > + * Returns u32: virtio device id > > > + * @get_vendor_id: Get virtio vendor id > > > + * @mdev: mediated device > > > + * Returns u32: virtio vendor id > > > + * @get_status: Get the device status > > > + * @mdev: mediated device > > > + * Returns u8: virtio device status > > > + * @set_status: Set the device status > > > + * @mdev: mediated device > > > + * @status: virtio device status > > > + * @get_config: Read from device specific confiugration > > > space > > configuration (and similar typos downward) > > > Let me fix. > > > > > > > + * @mdev: mediated device > > > + * @offset: offset from the beginning of > > > + * configuration space > > > + * @buf: buffer used to read to > > > + * @len: the length to read from > > > + * configration space > > > + * @set_config: Write to device specific confiugration space > > > + * @mdev: mediated device > > > + * @offset: offset from the beginning of > > > + * configuration space > > > + * @buf: buffer used to write from > > > + * @len: the length to write to > > > + * configration space > > > + * @get_version: Get the version of virtio mdev device > > > + * @mdev: mediated device > > > + * Returns integer: version of the device > > > + * @get_generation: Get device generaton > > > + * @mdev: mediated device > > > + * Returns u32: device generation > > > + */ > > > +struct virtio_mdev_device_ops { > > > + /* Virtqueue ops */ > > > + int (*set_vq_address)(struct mdev_device *mdev, > > > + u16 idx, u64 desc_area, u64 driver_area, > > > + u64 device_area); > > > + void (*set_vq_num)(struct mdev_device *mdev, u16 idx, u32 num); > > > + void (*kick_vq)(struct mdev_device *mdev, u16 idx); > > > + void (*set_vq_cb)(struct mdev_device *mdev, u16 idx, > > > + struct virtio_mdev_callback *cb); > > > + void (*set_vq_ready)(struct mdev_device *mdev, u16 idx, bool > > > ready); > > > + bool (*get_vq_ready)(struct mdev_device *mdev, u16 idx); > > > + int (*set_vq_state)(struct mdev_device *mdev, u16 idx, u64 state); > > > + u64 (*get_vq_state)(struct mdev_device *mdev, u16 idx); > > > + > > > + /* Device ops */ > > > + u16 (*get_vq_align)(struct mdev_device *mdev); > > > + u64 (*get_features)(struct mdev_device *mdev); > > > + int (*set_features)(struct mdev_device *mdev, u64 features); > > > + void (*set_config_cb)(struct mdev_device *mdev, > > > + struct virtio_mdev_callback *cb); > > > + u16 (*get_queue_max)(struct mdev_device *mdev); > > > + u32 (*get_device_id)(struct mdev_device *mdev); > > > + u32 (*get_vendor_id)(struct mdev_device *mdev); > > > + u8 (*get_status)(struct mdev_device *mdev); > > > + void (*set_status)(struct mdev_device *mdev, u8 status); > > > + void (*get_config)(struct mdev_device *mdev, unsigned int offset, > > > + void *buf, unsigned int len); > > > + void (*set_config)(struct mdev_device *mdev, unsigned int offset, > > > + const void *buf, unsigned int len); > > > + int (*get_version)(struct mdev_device *mdev); > > > + u32 (*get_generation)(struct mdev_device *mdev); > > > +}; > > I'm not sure how stable above ops are. > > > It's the kernel internal API, so there's no strict requirement for this. We > will export a version value for userspace for compatibility. Given it's tied to virtio we probably want kernel+userspace feature bits? > > > Does it make sense if defining > > just two callbacks here, e.g. vq_ctrl and device_ctrl, and then let the > > vendor driver to handle specific ops in each category (similar to how > > ioctl works)? > > > My understanding is that it introduce another indirection, you still need to > differ from different command, and it's less flexible than direct callback. > > What's the value of doing this? > > Thanks > > > > > > Thanks > > Kevin > > _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
