From: Mukesh Rathor <[email protected]> Add ioctl support for creating MSHV devices for a paritition. At present only VFIO device types are supported, but more could be added. At a high level, a partition ioctl to create device verifies it is of type VFIO and does some setup for bridge code in mshv_vfio.c. Adapted from KVM device ioctls.
Credits: Original author: Wei Liu <[email protected]> NB: Slightly modified from the original version. Signed-off-by: Mukesh Rathor <[email protected]> --- drivers/hv/mshv_root_main.c | 126 ++++++++++++++++++++++++++++++++++++ 1 file changed, 126 insertions(+) diff --git a/drivers/hv/mshv_root_main.c b/drivers/hv/mshv_root_main.c index 83c7bad269a0..27313419828d 100644 --- a/drivers/hv/mshv_root_main.c +++ b/drivers/hv/mshv_root_main.c @@ -1551,6 +1551,129 @@ mshv_partition_ioctl_initialize(struct mshv_partition *partition) return ret; } +static long mshv_device_attr_ioctl(struct mshv_device *mshv_dev, int cmd, + ulong uarg) +{ + struct mshv_device_attr attr; + const struct mshv_device_ops *devops = mshv_dev->device_ops; + + if (copy_from_user(&attr, (void __user *)uarg, sizeof(attr))) + return -EFAULT; + + switch (cmd) { + case MSHV_SET_DEVICE_ATTR: + if (devops->device_set_attr) + return devops->device_set_attr(mshv_dev, &attr); + break; + case MSHV_HAS_DEVICE_ATTR: + if (devops->device_has_attr) + return devops->device_has_attr(mshv_dev, &attr); + break; + } + + return -EPERM; +} + +static long mshv_device_fop_ioctl(struct file *filp, unsigned int cmd, + ulong uarg) +{ + struct mshv_device *mshv_dev = filp->private_data; + + switch (cmd) { + case MSHV_SET_DEVICE_ATTR: + case MSHV_HAS_DEVICE_ATTR: + return mshv_device_attr_ioctl(mshv_dev, cmd, uarg); + } + + return -ENOTTY; +} + +static int mshv_device_fop_release(struct inode *inode, struct file *filp) +{ + struct mshv_device *mshv_dev = filp->private_data; + struct mshv_partition *partition = mshv_dev->device_pt; + + if (mshv_dev->device_ops->device_release) { + mutex_lock(&partition->pt_mutex); + hlist_del(&mshv_dev->device_ptnode); + mshv_dev->device_ops->device_release(mshv_dev); + mutex_unlock(&partition->pt_mutex); + } + + mshv_partition_put(partition); + return 0; +} + +static const struct file_operations mshv_device_fops = { + .owner = THIS_MODULE, + .unlocked_ioctl = mshv_device_fop_ioctl, + .release = mshv_device_fop_release, +}; + +long mshv_partition_ioctl_create_device(struct mshv_partition *partition, + void __user *uarg) +{ + long rc; + struct mshv_create_device devargk; + struct mshv_device *mshv_dev; + const struct mshv_device_ops *vfio_ops; + int type; + + if (copy_from_user(&devargk, uarg, sizeof(devargk))) { + rc = -EFAULT; + goto out; + } + + /* At present, only VFIO is supported */ + if (devargk.type != MSHV_DEV_TYPE_VFIO) { + rc = -ENODEV; + goto out; + } + + if (devargk.flags & MSHV_CREATE_DEVICE_TEST) { + rc = 0; + goto out; + } + + mshv_dev = kzalloc(sizeof(*mshv_dev), GFP_KERNEL_ACCOUNT); + if (mshv_dev == NULL) { + rc = -ENOMEM; + goto out; + } + + vfio_ops = &mshv_vfio_device_ops; + mshv_dev->device_ops = vfio_ops; + mshv_dev->device_pt = partition; + + rc = vfio_ops->device_create(mshv_dev, type); + if (rc < 0) { + kfree(mshv_dev); + goto out; + } + + hlist_add_head(&mshv_dev->device_ptnode, &partition->pt_devices); + + mshv_partition_get(partition); + rc = anon_inode_getfd(vfio_ops->device_name, &mshv_device_fops, + mshv_dev, O_RDWR | O_CLOEXEC); + if (rc < 0) { + mshv_partition_put(partition); + hlist_del(&mshv_dev->device_ptnode); + vfio_ops->device_release(mshv_dev); + goto out; + } + + devargk.fd = rc; + rc = 0; + + if (copy_to_user(uarg, &devargk, sizeof(devargk))) { + rc = -EFAULT; + goto out; + } +out: + return rc; +} + static long mshv_partition_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg) { @@ -1587,6 +1710,9 @@ mshv_partition_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg) case MSHV_ROOT_HVCALL: ret = mshv_ioctl_passthru_hvcall(partition, true, uarg); break; + case MSHV_CREATE_DEVICE: + ret = mshv_partition_ioctl_create_device(partition, uarg); + break; default: ret = -ENOTTY; } -- 2.51.2.vfs.0.1
