Commit 9eefba80 authored by Yi Liu's avatar Yi Liu Committed by Jason Gunthorpe
Browse files

vfio: Move vfio group specific code into group.c 

This prepares for compiling out vfio group after vfio device cdev is
added. No vfio_group decode code should be in vfio_main.c, and neither
device->group reference should be in vfio_main.c.

No functional change is intended.

Link: https://lore.kernel.org/r/20221201145535.589687-11-yi.l.liu@intel.com


Reviewed-by: default avatarKevin Tian <kevin.tian@intel.com>
Reviewed-by: default avatarJason Gunthorpe <jgg@nvidia.com>
Reviewed-by: default avatarAlex Williamson <alex.williamson@redhat.com>
Tested-by: default avatarYu He <yu.he@intel.com>
Tested-by: default avatarLixiao Yang <lixiao.yang@intel.com>
Signed-off-by: default avatarYi Liu <yi.l.liu@intel.com>
Signed-off-by: default avatarJason Gunthorpe <jgg@nvidia.com>
parent 8da7a0e7

drivers/vfio/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -4,6 +4,7 @@ vfio_virqfd-y := virqfd.o 
obj-$(CONFIG_VFIO) += vfio.o



vfio-y += vfio_main.o \

	  group.o \

	  iova_bitmap.o

vfio-$(CONFIG_IOMMUFD) += iommufd.o

vfio-$(CONFIG_VFIO_CONTAINER) += container.o

drivers/vfio/group.c

0 → 100644
+877 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0-only

/*

 * VFIO core

 *

 * Copyright (C) 2012 Red Hat, Inc.  All rights reserved.

 *     Author: Alex Williamson <alex.williamson@redhat.com>

 *

 * Derived from original vfio:

 * Copyright 2010 Cisco Systems, Inc.  All rights reserved.

 * Author: Tom Lyon, pugs@cisco.com

 */



#include <linux/vfio.h>

#include <linux/iommufd.h>

#include <linux/anon_inodes.h>

#include "vfio.h"



static struct vfio {

	struct class			*class;

	struct list_head		group_list;

	struct mutex			group_lock; /* locks group_list */

	struct ida			group_ida;

	dev_t				group_devt;

} vfio;



static struct vfio_device *vfio_device_get_from_name(struct vfio_group *group,

						     char *buf)

{

	struct vfio_device *it, *device = ERR_PTR(-ENODEV);



	mutex_lock(&group->device_lock);

	list_for_each_entry(it, &group->device_list, group_next) {

		int ret;



		if (it->ops->match) {

			ret = it->ops->match(it, buf);

			if (ret < 0) {

				device = ERR_PTR(ret);

				break;

			}

		} else {

			ret = !strcmp(dev_name(it->dev), buf);

		}



		if (ret && vfio_device_try_get_registration(it)) {

			device = it;

			break;

		}

	}

	mutex_unlock(&group->device_lock);



	return device;

}



/*

 * VFIO Group fd, /dev/vfio/$GROUP

 */

static bool vfio_group_has_iommu(struct vfio_group *group)

{

	lockdep_assert_held(&group->group_lock);

	/*

	 * There can only be users if there is a container, and if there is a

	 * container there must be users.

	 */

	WARN_ON(!group->container != !group->container_users);



	return group->container || group->iommufd;

}



/*

 * VFIO_GROUP_UNSET_CONTAINER should fail if there are other users or

 * if there was no container to unset.  Since the ioctl is called on

 * the group, we know that still exists, therefore the only valid

 * transition here is 1->0.

 */

static int vfio_group_ioctl_unset_container(struct vfio_group *group)

{

	int ret = 0;



	mutex_lock(&group->group_lock);

	if (!vfio_group_has_iommu(group)) {

		ret = -EINVAL;

		goto out_unlock;

	}

	if (group->container) {

		if (group->container_users != 1) {

			ret = -EBUSY;

			goto out_unlock;

		}

		vfio_group_detach_container(group);

	}

	if (group->iommufd) {

		iommufd_ctx_put(group->iommufd);

		group->iommufd = NULL;

	}



out_unlock:

	mutex_unlock(&group->group_lock);

	return ret;

}



static int vfio_group_ioctl_set_container(struct vfio_group *group,

					  int __user *arg)

{

	struct vfio_container *container;

	struct iommufd_ctx *iommufd;

	struct fd f;

	int ret;

	int fd;



	if (get_user(fd, arg))

		return -EFAULT;



	f = fdget(fd);

	if (!f.file)

		return -EBADF;



	mutex_lock(&group->group_lock);

	if (vfio_group_has_iommu(group)) {

		ret = -EINVAL;

		goto out_unlock;

	}

	if (!group->iommu_group) {

		ret = -ENODEV;

		goto out_unlock;

	}



	container = vfio_container_from_file(f.file);

	if (container) {

		ret = vfio_container_attach_group(container, group);

		goto out_unlock;

	}



	iommufd = iommufd_ctx_from_file(f.file);

	if (!IS_ERR(iommufd)) {

		u32 ioas_id;



		ret = iommufd_vfio_compat_ioas_id(iommufd, &ioas_id);

		if (ret) {

			iommufd_ctx_put(group->iommufd);

			goto out_unlock;

		}



		group->iommufd = iommufd;

		goto out_unlock;

	}



	/* The FD passed is not recognized. */

	ret = -EBADFD;



out_unlock:

	mutex_unlock(&group->group_lock);

	fdput(f);

	return ret;

}



static int vfio_device_group_open(struct vfio_device *device)

{

	int ret;



	mutex_lock(&device->group->group_lock);

	if (!vfio_group_has_iommu(device->group)) {

		ret = -EINVAL;

		goto out_unlock;

	}



	/*

	 * Here we pass the KVM pointer with the group under the lock.  If the

	 * device driver will use it, it must obtain a reference and release it

	 * during close_device.

	 */

	ret = vfio_device_open(device, device->group->iommufd,

			       device->group->kvm);



out_unlock:

	mutex_unlock(&device->group->group_lock);

	return ret;

}



void vfio_device_group_close(struct vfio_device *device)

{

	mutex_lock(&device->group->group_lock);

	vfio_device_close(device, device->group->iommufd);

	mutex_unlock(&device->group->group_lock);

}



static struct file *vfio_device_open_file(struct vfio_device *device)

{

	struct file *filep;

	int ret;



	ret = vfio_device_group_open(device);

	if (ret)

		goto err_out;



	/*

	 * We can't use anon_inode_getfd() because we need to modify

	 * the f_mode flags directly to allow more than just ioctls

	 */

	filep = anon_inode_getfile("[vfio-device]", &vfio_device_fops,

				   device, O_RDWR);

	if (IS_ERR(filep)) {

		ret = PTR_ERR(filep);

		goto err_close_device;

	}



	/*

	 * TODO: add an anon_inode interface to do this.

	 * Appears to be missing by lack of need rather than

	 * explicitly prevented.  Now there's need.

	 */

	filep->f_mode |= (FMODE_PREAD | FMODE_PWRITE);



	if (device->group->type == VFIO_NO_IOMMU)

		dev_warn(device->dev, "vfio-noiommu device opened by user "

			 "(%s:%d)\n", current->comm, task_pid_nr(current));

	/*

	 * On success the ref of device is moved to the file and

	 * put in vfio_device_fops_release()

	 */

	return filep;



err_close_device:

	vfio_device_group_close(device);

err_out:

	return ERR_PTR(ret);

}



static int vfio_group_ioctl_get_device_fd(struct vfio_group *group,

					  char __user *arg)

{

	struct vfio_device *device;

	struct file *filep;

	char *buf;

	int fdno;

	int ret;



	buf = strndup_user(arg, PAGE_SIZE);

	if (IS_ERR(buf))

		return PTR_ERR(buf);



	device = vfio_device_get_from_name(group, buf);

	kfree(buf);

	if (IS_ERR(device))

		return PTR_ERR(device);



	fdno = get_unused_fd_flags(O_CLOEXEC);

	if (fdno < 0) {

		ret = fdno;

		goto err_put_device;

	}



	filep = vfio_device_open_file(device);

	if (IS_ERR(filep)) {

		ret = PTR_ERR(filep);

		goto err_put_fdno;

	}



	fd_install(fdno, filep);

	return fdno;



err_put_fdno:

	put_unused_fd(fdno);

err_put_device:

	vfio_device_put_registration(device);

	return ret;

}



static int vfio_group_ioctl_get_status(struct vfio_group *group,

				       struct vfio_group_status __user *arg)

{

	unsigned long minsz = offsetofend(struct vfio_group_status, flags);

	struct vfio_group_status status;



	if (copy_from_user(&status, arg, minsz))

		return -EFAULT;



	if (status.argsz < minsz)

		return -EINVAL;



	status.flags = 0;



	mutex_lock(&group->group_lock);

	if (!group->iommu_group) {

		mutex_unlock(&group->group_lock);

		return -ENODEV;

	}



	/*

	 * With the container FD the iommu_group_claim_dma_owner() is done

	 * during SET_CONTAINER but for IOMMFD this is done during

	 * VFIO_GROUP_GET_DEVICE_FD. Meaning that with iommufd

	 * VFIO_GROUP_FLAGS_VIABLE could be set but GET_DEVICE_FD will fail due

	 * to viability.

	 */

	if (vfio_group_has_iommu(group))

		status.flags |= VFIO_GROUP_FLAGS_CONTAINER_SET |

				VFIO_GROUP_FLAGS_VIABLE;

	else if (!iommu_group_dma_owner_claimed(group->iommu_group))

		status.flags |= VFIO_GROUP_FLAGS_VIABLE;

	mutex_unlock(&group->group_lock);



	if (copy_to_user(arg, &status, minsz))

		return -EFAULT;

	return 0;

}



static long vfio_group_fops_unl_ioctl(struct file *filep,

				      unsigned int cmd, unsigned long arg)

{

	struct vfio_group *group = filep->private_data;

	void __user *uarg = (void __user *)arg;



	switch (cmd) {

	case VFIO_GROUP_GET_DEVICE_FD:

		return vfio_group_ioctl_get_device_fd(group, uarg);

	case VFIO_GROUP_GET_STATUS:

		return vfio_group_ioctl_get_status(group, uarg);

	case VFIO_GROUP_SET_CONTAINER:

		return vfio_group_ioctl_set_container(group, uarg);

	case VFIO_GROUP_UNSET_CONTAINER:

		return vfio_group_ioctl_unset_container(group);

	default:

		return -ENOTTY;

	}

}



static int vfio_group_fops_open(struct inode *inode, struct file *filep)

{

	struct vfio_group *group =

		container_of(inode->i_cdev, struct vfio_group, cdev);

	int ret;



	mutex_lock(&group->group_lock);



	/*

	 * drivers can be zero if this races with vfio_device_remove_group(), it

	 * will be stable at 0 under the group rwsem

	 */

	if (refcount_read(&group->drivers) == 0) {

		ret = -ENODEV;

		goto out_unlock;

	}



	if (group->type == VFIO_NO_IOMMU && !capable(CAP_SYS_RAWIO)) {

		ret = -EPERM;

		goto out_unlock;

	}



	/*

	 * Do we need multiple instances of the group open?  Seems not.

	 */

	if (group->opened_file) {

		ret = -EBUSY;

		goto out_unlock;

	}

	group->opened_file = filep;

	filep->private_data = group;

	ret = 0;

out_unlock:

	mutex_unlock(&group->group_lock);

	return ret;

}



static int vfio_group_fops_release(struct inode *inode, struct file *filep)

{

	struct vfio_group *group = filep->private_data;



	filep->private_data = NULL;



	mutex_lock(&group->group_lock);

	/*

	 * Device FDs hold a group file reference, therefore the group release

	 * is only called when there are no open devices.

	 */

	WARN_ON(group->notifier.head);

	if (group->container)

		vfio_group_detach_container(group);

	if (group->iommufd) {

		iommufd_ctx_put(group->iommufd);

		group->iommufd = NULL;

	}

	group->opened_file = NULL;

	mutex_unlock(&group->group_lock);

	return 0;

}



static const struct file_operations vfio_group_fops = {

	.owner		= THIS_MODULE,

	.unlocked_ioctl	= vfio_group_fops_unl_ioctl,

	.compat_ioctl	= compat_ptr_ioctl,

	.open		= vfio_group_fops_open,

	.release	= vfio_group_fops_release,

};



/*

 * Group objects - create, release, get, put, search

 */

static struct vfio_group *

vfio_group_find_from_iommu(struct iommu_group *iommu_group)

{

	struct vfio_group *group;



	lockdep_assert_held(&vfio.group_lock);



	/*

	 * group->iommu_group from the vfio.group_list cannot be NULL

	 * under the vfio.group_lock.

	 */

	list_for_each_entry(group, &vfio.group_list, vfio_next) {

		if (group->iommu_group == iommu_group)

			return group;

	}

	return NULL;

}



static void vfio_group_release(struct device *dev)

{

	struct vfio_group *group = container_of(dev, struct vfio_group, dev);



	mutex_destroy(&group->device_lock);

	mutex_destroy(&group->group_lock);

	WARN_ON(group->iommu_group);

	ida_free(&vfio.group_ida, MINOR(group->dev.devt));

	kfree(group);

}



static struct vfio_group *vfio_group_alloc(struct iommu_group *iommu_group,

					   enum vfio_group_type type)

{

	struct vfio_group *group;

	int minor;



	group = kzalloc(sizeof(*group), GFP_KERNEL);

	if (!group)

		return ERR_PTR(-ENOMEM);



	minor = ida_alloc_max(&vfio.group_ida, MINORMASK, GFP_KERNEL);

	if (minor < 0) {

		kfree(group);

		return ERR_PTR(minor);

	}



	device_initialize(&group->dev);

	group->dev.devt = MKDEV(MAJOR(vfio.group_devt), minor);

	group->dev.class = vfio.class;

	group->dev.release = vfio_group_release;

	cdev_init(&group->cdev, &vfio_group_fops);

	group->cdev.owner = THIS_MODULE;



	refcount_set(&group->drivers, 1);

	mutex_init(&group->group_lock);

	INIT_LIST_HEAD(&group->device_list);

	mutex_init(&group->device_lock);

	group->iommu_group = iommu_group;

	/* put in vfio_group_release() */

	iommu_group_ref_get(iommu_group);

	group->type = type;

	BLOCKING_INIT_NOTIFIER_HEAD(&group->notifier);



	return group;

}



static struct vfio_group *vfio_create_group(struct iommu_group *iommu_group,

		enum vfio_group_type type)

{

	struct vfio_group *group;

	struct vfio_group *ret;

	int err;



	lockdep_assert_held(&vfio.group_lock);



	group = vfio_group_alloc(iommu_group, type);

	if (IS_ERR(group))

		return group;



	err = dev_set_name(&group->dev, "%s%d",

			   group->type == VFIO_NO_IOMMU ? "noiommu-" : "",

			   iommu_group_id(iommu_group));

	if (err) {

		ret = ERR_PTR(err);

		goto err_put;

	}



	err = cdev_device_add(&group->cdev, &group->dev);

	if (err) {

		ret = ERR_PTR(err);

		goto err_put;

	}



	list_add(&group->vfio_next, &vfio.group_list);



	return group;



err_put:

	put_device(&group->dev);

	return ret;

}



static struct vfio_group *vfio_noiommu_group_alloc(struct device *dev,

		enum vfio_group_type type)

{

	struct iommu_group *iommu_group;

	struct vfio_group *group;

	int ret;



	iommu_group = iommu_group_alloc();

	if (IS_ERR(iommu_group))

		return ERR_CAST(iommu_group);



	ret = iommu_group_set_name(iommu_group, "vfio-noiommu");

	if (ret)

		goto out_put_group;

	ret = iommu_group_add_device(iommu_group, dev);

	if (ret)

		goto out_put_group;



	mutex_lock(&vfio.group_lock);

	group = vfio_create_group(iommu_group, type);

	mutex_unlock(&vfio.group_lock);

	if (IS_ERR(group)) {

		ret = PTR_ERR(group);

		goto out_remove_device;

	}

	iommu_group_put(iommu_group);

	return group;



out_remove_device:

	iommu_group_remove_device(dev);

out_put_group:

	iommu_group_put(iommu_group);

	return ERR_PTR(ret);

}



static bool vfio_group_has_device(struct vfio_group *group, struct device *dev)

{

	struct vfio_device *device;



	mutex_lock(&group->device_lock);

	list_for_each_entry(device, &group->device_list, group_next) {

		if (device->dev == dev) {

			mutex_unlock(&group->device_lock);

			return true;

		}

	}

	mutex_unlock(&group->device_lock);

	return false;

}



static struct vfio_group *vfio_group_find_or_alloc(struct device *dev)

{

	struct iommu_group *iommu_group;

	struct vfio_group *group;



	iommu_group = iommu_group_get(dev);

	if (!iommu_group && vfio_noiommu) {

		/*

		 * With noiommu enabled, create an IOMMU group for devices that

		 * don't already have one, implying no IOMMU hardware/driver

		 * exists.  Taint the kernel because we're about to give a DMA

		 * capable device to a user without IOMMU protection.

		 */

		group = vfio_noiommu_group_alloc(dev, VFIO_NO_IOMMU);

		if (!IS_ERR(group)) {

			add_taint(TAINT_USER, LOCKDEP_STILL_OK);

			dev_warn(dev, "Adding kernel taint for vfio-noiommu group on device\n");

		}

		return group;

	}



	if (!iommu_group)

		return ERR_PTR(-EINVAL);



	/*

	 * VFIO always sets IOMMU_CACHE because we offer no way for userspace to

	 * restore cache coherency. It has to be checked here because it is only

	 * valid for cases where we are using iommu groups.

	 */

	if (!device_iommu_capable(dev, IOMMU_CAP_CACHE_COHERENCY)) {

		iommu_group_put(iommu_group);

		return ERR_PTR(-EINVAL);

	}



	mutex_lock(&vfio.group_lock);

	group = vfio_group_find_from_iommu(iommu_group);

	if (group) {

		if (WARN_ON(vfio_group_has_device(group, dev)))

			group = ERR_PTR(-EINVAL);

		else

			refcount_inc(&group->drivers);

	} else {

		group = vfio_create_group(iommu_group, VFIO_IOMMU);

	}

	mutex_unlock(&vfio.group_lock);



	/* The vfio_group holds a reference to the iommu_group */

	iommu_group_put(iommu_group);

	return group;

}



int vfio_device_set_group(struct vfio_device *device,

			  enum vfio_group_type type)

{

	struct vfio_group *group;



	if (type == VFIO_IOMMU)

		group = vfio_group_find_or_alloc(device->dev);

	else

		group = vfio_noiommu_group_alloc(device->dev, type);



	if (IS_ERR(group))

		return PTR_ERR(group);



	/* Our reference on group is moved to the device */

	device->group = group;

	return 0;

}



void vfio_device_remove_group(struct vfio_device *device)

{

	struct vfio_group *group = device->group;

	struct iommu_group *iommu_group;



	if (group->type == VFIO_NO_IOMMU || group->type == VFIO_EMULATED_IOMMU)

		iommu_group_remove_device(device->dev);



	/* Pairs with vfio_create_group() / vfio_group_get_from_iommu() */

	if (!refcount_dec_and_mutex_lock(&group->drivers, &vfio.group_lock))

		return;

	list_del(&group->vfio_next);



	/*

	 * We could concurrently probe another driver in the group that might

	 * race vfio_device_remove_group() with vfio_get_group(), so we have to

	 * ensure that the sysfs is all cleaned up under lock otherwise the

	 * cdev_device_add() will fail due to the name aready existing.

	 */

	cdev_device_del(&group->cdev, &group->dev);



	mutex_lock(&group->group_lock);

	/*

	 * These data structures all have paired operations that can only be

	 * undone when the caller holds a live reference on the device. Since

	 * all pairs must be undone these WARN_ON's indicate some caller did not

	 * properly hold the group reference.

	 */

	WARN_ON(!list_empty(&group->device_list));

	WARN_ON(group->notifier.head);



	/*

	 * Revoke all users of group->iommu_group. At this point we know there

	 * are no devices active because we are unplugging the last one. Setting

	 * iommu_group to NULL blocks all new users.

	 */

	if (group->container)

		vfio_group_detach_container(group);

	iommu_group = group->iommu_group;

	group->iommu_group = NULL;

	mutex_unlock(&group->group_lock);

	mutex_unlock(&vfio.group_lock);



	iommu_group_put(iommu_group);

	put_device(&group->dev);

}



void vfio_device_group_register(struct vfio_device *device)

{

	mutex_lock(&device->group->device_lock);

	list_add(&device->group_next, &device->group->device_list);

	mutex_unlock(&device->group->device_lock);

}



void vfio_device_group_unregister(struct vfio_device *device)

{

	mutex_lock(&device->group->device_lock);

	list_del(&device->group_next);

	mutex_unlock(&device->group->device_lock);

}



int vfio_device_group_use_iommu(struct vfio_device *device)

{

	struct vfio_group *group = device->group;

	int ret = 0;



	lockdep_assert_held(&group->group_lock);



	if (WARN_ON(!group->container))

		return -EINVAL;



	ret = vfio_group_use_container(group);

	if (ret)

		return ret;

	vfio_device_container_register(device);

	return 0;

}



void vfio_device_group_unuse_iommu(struct vfio_device *device)

{

	struct vfio_group *group = device->group;



	lockdep_assert_held(&group->group_lock);



	if (WARN_ON(!group->container))

		return;



	vfio_device_container_unregister(device);

	vfio_group_unuse_container(group);

}



bool vfio_device_has_container(struct vfio_device *device)

{

	return device->group->container;

}



/**

 * vfio_file_iommu_group - Return the struct iommu_group for the vfio group file

 * @file: VFIO group file

 *

 * The returned iommu_group is valid as long as a ref is held on the file. This

 * returns a reference on the group. This function is deprecated, only the SPAPR

 * path in kvm should call it.

 */

struct iommu_group *vfio_file_iommu_group(struct file *file)

{

	struct vfio_group *group = file->private_data;

	struct iommu_group *iommu_group = NULL;



	if (!IS_ENABLED(CONFIG_SPAPR_TCE_IOMMU))

		return NULL;



	if (!vfio_file_is_group(file))

		return NULL;



	mutex_lock(&group->group_lock);

	if (group->iommu_group) {

		iommu_group = group->iommu_group;

		iommu_group_ref_get(iommu_group);

	}

	mutex_unlock(&group->group_lock);

	return iommu_group;

}

EXPORT_SYMBOL_GPL(vfio_file_iommu_group);



/**

 * vfio_file_is_group - True if the file is usable with VFIO aPIS

 * @file: VFIO group file

 */

bool vfio_file_is_group(struct file *file)

{

	return file->f_op == &vfio_group_fops;

}

EXPORT_SYMBOL_GPL(vfio_file_is_group);



/**

 * vfio_file_enforced_coherent - True if the DMA associated with the VFIO file

 *        is always CPU cache coherent

 * @file: VFIO group file

 *

 * Enforced coherency means that the IOMMU ignores things like the PCIe no-snoop

 * bit in DMA transactions. A return of false indicates that the user has

 * rights to access additional instructions such as wbinvd on x86.

 */

bool vfio_file_enforced_coherent(struct file *file)

{

	struct vfio_group *group = file->private_data;

	struct vfio_device *device;

	bool ret = true;



	if (!vfio_file_is_group(file))

		return true;



	/*

	 * If the device does not have IOMMU_CAP_ENFORCE_CACHE_COHERENCY then

	 * any domain later attached to it will also not support it. If the cap

	 * is set then the iommu_domain eventually attached to the device/group

	 * must use a domain with enforce_cache_coherency().

	 */

	mutex_lock(&group->device_lock);

	list_for_each_entry(device, &group->device_list, group_next) {

		if (!device_iommu_capable(device->dev,

					  IOMMU_CAP_ENFORCE_CACHE_COHERENCY)) {

			ret = false;

			break;

		}

	}

	mutex_unlock(&group->device_lock);

	return ret;

}

EXPORT_SYMBOL_GPL(vfio_file_enforced_coherent);



/**

 * vfio_file_set_kvm - Link a kvm with VFIO drivers

 * @file: VFIO group file

 * @kvm: KVM to link

 *

 * When a VFIO device is first opened the KVM will be available in

 * device->kvm if one was associated with the group.

 */

void vfio_file_set_kvm(struct file *file, struct kvm *kvm)

{

	struct vfio_group *group = file->private_data;



	if (!vfio_file_is_group(file))

		return;



	mutex_lock(&group->group_lock);

	group->kvm = kvm;

	mutex_unlock(&group->group_lock);

}

EXPORT_SYMBOL_GPL(vfio_file_set_kvm);



/**

 * vfio_file_has_dev - True if the VFIO file is a handle for device

 * @file: VFIO file to check

 * @device: Device that must be part of the file

 *

 * Returns true if given file has permission to manipulate the given device.

 */

bool vfio_file_has_dev(struct file *file, struct vfio_device *device)

{

	struct vfio_group *group = file->private_data;



	if (!vfio_file_is_group(file))

		return false;



	return group == device->group;

}

EXPORT_SYMBOL_GPL(vfio_file_has_dev);



static char *vfio_devnode(struct device *dev, umode_t *mode)

{

	return kasprintf(GFP_KERNEL, "vfio/%s", dev_name(dev));

}



int __init vfio_group_init(void)

{

	int ret;



	ida_init(&vfio.group_ida);

	mutex_init(&vfio.group_lock);

	INIT_LIST_HEAD(&vfio.group_list);



	ret = vfio_container_init();

	if (ret)

		return ret;



	/* /dev/vfio/$GROUP */

	vfio.class = class_create(THIS_MODULE, "vfio");

	if (IS_ERR(vfio.class)) {

		ret = PTR_ERR(vfio.class);

		goto err_group_class;

	}



	vfio.class->devnode = vfio_devnode;



	ret = alloc_chrdev_region(&vfio.group_devt, 0, MINORMASK + 1, "vfio");

	if (ret)

		goto err_alloc_chrdev;

	return 0;



err_alloc_chrdev:

	class_destroy(vfio.class);

	vfio.class = NULL;

err_group_class:

	vfio_container_cleanup();

	return ret;

}



void vfio_group_cleanup(void)

{

	WARN_ON(!list_empty(&vfio.group_list));

	ida_destroy(&vfio.group_ida);

	unregister_chrdev_region(vfio.group_devt, MINORMASK + 1);

	class_destroy(vfio.class);

	vfio.class = NULL;

	vfio_container_cleanup();

}

drivers/vfio/vfio.h

+22 −0
Original line number Diff line number Diff line
@@ -6,6 +6,7 @@ 
#ifndef __VFIO_VFIO_H__

#define __VFIO_VFIO_H__



#include <linux/file.h>

#include <linux/device.h>

#include <linux/cdev.h>

#include <linux/module.h>
@@ -15,6 +16,15 @@ struct iommu_group; 
struct vfio_device;

struct vfio_container;



void vfio_device_put_registration(struct vfio_device *device);

bool vfio_device_try_get_registration(struct vfio_device *device);

int vfio_device_open(struct vfio_device *device,

		     struct iommufd_ctx *iommufd, struct kvm *kvm);

void vfio_device_close(struct vfio_device *device,

		       struct iommufd_ctx *iommufd);



extern const struct file_operations vfio_device_fops;



enum vfio_group_type {

	/*

	 * Physical device with IOMMU backing.
@@ -66,6 +76,18 @@ struct vfio_group { 
	struct iommufd_ctx		*iommufd;

};



int vfio_device_set_group(struct vfio_device *device,

			  enum vfio_group_type type);

void vfio_device_remove_group(struct vfio_device *device);

void vfio_device_group_register(struct vfio_device *device);

void vfio_device_group_unregister(struct vfio_device *device);

int vfio_device_group_use_iommu(struct vfio_device *device);

void vfio_device_group_unuse_iommu(struct vfio_device *device);

void vfio_device_group_close(struct vfio_device *device);

bool vfio_device_has_container(struct vfio_device *device);

int __init vfio_group_init(void);

void vfio_group_cleanup(void);



#if IS_ENABLED(CONFIG_VFIO_CONTAINER)

/* events for the backend driver notify callback */

enum vfio_iommu_notify_type {

drivers/vfio/vfio_main.c

+7 −870

File changed.

Preview size limit exceeded, changes collapsed.