// SPDX-License-Identifier: GPL-2.0-only/* * Copyright (c) 2023 Intel Corporation. */#include <linux/vfio.h>#include <linux/iommufd.h> #include "vfio.h" static dev_t device_devt; void vfio_init_device_cdev(struct vfio_device *device){	device->device.devt = MKDEV(MAJOR(device_devt), device->index);	cdev_init(&device->cdev, &vfio_device_fops);	device->cdev.owner = THIS_MODULE;} /* * device access via the fd opened by this function is blocked until * .open_device() is called successfully during BIND_IOMMUFD. */int vfio_device_fops_cdev_open(struct inode *inode, struct file *filep){	struct vfio_device *device = container_of(inode->i_cdev,						  struct vfio_device, cdev);	struct vfio_device_file *df;	int ret; 	/* Paired with the put in vfio_device_fops_release() */	if (!vfio_device_try_get_registration(device))		return -ENODEV; 	df = vfio_allocate_device_file(device);	if (IS_ERR(df)) {		ret = PTR_ERR(df);		goto err_put_registration;	} 	filep->private_data = df; 	/*	 * Use the pseudo fs inode on the device to link all mmaps	 * to the same address space, allowing us to unmap all vmas	 * associated to this device using unmap_mapping_range().	 */	filep->f_mapping = device->inode->i_mapping; 	return 0; err_put_registration:	vfio_device_put_registration(device);	return ret;} static void vfio_df_get_kvm_safe(struct vfio_device_file *df){	spin_lock(&df->kvm_ref_lock);	vfio_device_get_kvm_safe(df->device, df->kvm);	spin_unlock(&df->kvm_ref_lock);} long vfio_df_ioctl_bind_iommufd(struct vfio_device_file *df,				struct vfio_device_bind_iommufd __user *arg){	struct vfio_device *device = df->device;	struct vfio_device_bind_iommufd bind;	unsigned long minsz;	int ret; 	static_assert(__same_type(arg->out_devid, df->devid)); 	minsz = offsetofend(struct vfio_device_bind_iommufd, out_devid); 	if (copy_from_user(&bind, arg, minsz))		return -EFAULT; 	if (bind.argsz < minsz || bind.flags || bind.iommufd < 0)		return -EINVAL; 	/* BIND_IOMMUFD only allowed for cdev fds */	if (df->group)		return -EINVAL; 	ret = vfio_device_block_group(device);	if (ret)		return ret; 	mutex_lock(&device->dev_set->lock);	/* one device cannot be bound twice */	if (df->access_granted) {		ret = -EINVAL;		goto out_unlock;	} 	df->iommufd = iommufd_ctx_from_fd(bind.iommufd);	if (IS_ERR(df->iommufd)) {		ret = PTR_ERR(df->iommufd);		df->iommufd = NULL;		goto out_unlock;	} 	/*	 * Before the device open, get the KVM pointer currently	 * associated with the device file (if there is) and obtain	 * a reference.  This reference is held until device closed.	 * Save the pointer in the device for use by drivers.	 */	vfio_df_get_kvm_safe(df); 	ret = vfio_df_open(df);	if (ret)		goto out_put_kvm; 	ret = copy_to_user(&arg->out_devid, &df->devid,			   sizeof(df->devid)) ? -EFAULT : 0;	if (ret)		goto out_close_device; 	device->cdev_opened = true;	/*	 * Paired with smp_load_acquire() in vfio_device_fops::ioctl/	 * read/write/mmap	 */	smp_store_release(&df->access_granted, true);	mutex_unlock(&device->dev_set->lock);	return 0; out_close_device:	vfio_df_close(df);out_put_kvm:	vfio_device_put_kvm(device);	iommufd_ctx_put(df->iommufd);	df->iommufd = NULL;out_unlock:	mutex_unlock(&device->dev_set->lock);	vfio_device_unblock_group(device);	return ret;} void vfio_df_unbind_iommufd(struct vfio_device_file *df){	struct vfio_device *device = df->device; 	/*	 * In the time of close, there is no contention with another one	 * changing this flag.  So read df->access_granted without lock	 * and no smp_load_acquire() is ok.	 */	if (!df->access_granted)		return; 	mutex_lock(&device->dev_set->lock);	vfio_df_close(df);	vfio_device_put_kvm(device);	iommufd_ctx_put(df->iommufd);	device->cdev_opened = false;	mutex_unlock(&device->dev_set->lock);	vfio_device_unblock_group(device);} int vfio_df_ioctl_attach_pt(struct vfio_device_file *df,			    struct vfio_device_attach_iommufd_pt __user *arg){	struct vfio_device *device = df->device;	struct vfio_device_attach_iommufd_pt attach;	unsigned long minsz;	int ret; 	minsz = offsetofend(struct vfio_device_attach_iommufd_pt, pt_id); 	if (copy_from_user(&attach, arg, minsz))		return -EFAULT; 	if (attach.argsz < minsz || attach.flags)		return -EINVAL; 	mutex_lock(&device->dev_set->lock);	ret = device->ops->attach_ioas(device, &attach.pt_id);	if (ret)		goto out_unlock; 	if (copy_to_user(&arg->pt_id, &attach.pt_id, sizeof(attach.pt_id))) {		ret = -EFAULT;		goto out_detach;	}	mutex_unlock(&device->dev_set->lock); 	return 0; out_detach:	device->ops->detach_ioas(device);out_unlock:	mutex_unlock(&device->dev_set->lock);	return ret;} int vfio_df_ioctl_detach_pt(struct vfio_device_file *df,			    struct vfio_device_detach_iommufd_pt __user *arg){	struct vfio_device *device = df->device;	struct vfio_device_detach_iommufd_pt detach;	unsigned long minsz; 	minsz = offsetofend(struct vfio_device_detach_iommufd_pt, flags); 	if (copy_from_user(&detach, arg, minsz))		return -EFAULT; 	if (detach.argsz < minsz || detach.flags)		return -EINVAL; 	mutex_lock(&device->dev_set->lock);	device->ops->detach_ioas(device);	mutex_unlock(&device->dev_set->lock); 	return 0;} static char *vfio_device_devnode(const struct device *dev, umode_t *mode){	return kasprintf(GFP_KERNEL, "vfio/devices/%s", dev_name(dev));} int vfio_cdev_init(struct class *device_class){	device_class->devnode = vfio_device_devnode;	return alloc_chrdev_region(&device_devt, 0,				   MINORMASK + 1, "vfio-dev");} void vfio_cdev_cleanup(void){	unregister_chrdev_region(device_devt, MINORMASK + 1);}