linux/drivers/iommu/iommufd/main.c

// SPDX-License-Identifier: GPL-2.0-only
/* Copyright (C) 2021 Intel Corporation
 * Copyright (c) 2021-2022, NVIDIA CORPORATION & AFFILIATES
 *
 * iommufd provides control over the IOMMU HW objects created by IOMMU kernel
 * drivers. IOMMU HW objects revolve around IO page tables that map incoming DMA
 * addresses (IOVA) to CPU addresses.
 */
#define pr_fmt(fmt) …

#include <linux/bug.h>
#include <linux/file.h>
#include <linux/fs.h>
#include <linux/iommufd.h>
#include <linux/miscdevice.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/slab.h>
#include <uapi/linux/iommufd.h>

#include "io_pagetable.h"
#include "iommufd_private.h"
#include "iommufd_test.h"

struct iommufd_object_ops { … };
static const struct iommufd_object_ops iommufd_object_ops[];
static struct miscdevice vfio_misc_dev;

struct iommufd_object *_iommufd_object_alloc(struct iommufd_ctx *ictx,
					     size_t size,
					     enum iommufd_object_type type)
{ … }

/*
 * Allow concurrent access to the object.
 *
 * Once another thread can see the object pointer it can prevent object
 * destruction. Expect for special kernel-only objects there is no in-kernel way
 * to reliably destroy a single object. Thus all APIs that are creating objects
 * must use iommufd_object_abort() to handle their errors and only call
 * iommufd_object_finalize() once object creation cannot fail.
 */
void iommufd_object_finalize(struct iommufd_ctx *ictx,
			     struct iommufd_object *obj)
{ … }

/* Undo _iommufd_object_alloc() if iommufd_object_finalize() was not called */
void iommufd_object_abort(struct iommufd_ctx *ictx, struct iommufd_object *obj)
{ … }

/*
 * Abort an object that has been fully initialized and needs destroy, but has
 * not been finalized.
 */
void iommufd_object_abort_and_destroy(struct iommufd_ctx *ictx,
				      struct iommufd_object *obj)
{ … }

struct iommufd_object *iommufd_get_object(struct iommufd_ctx *ictx, u32 id,
					  enum iommufd_object_type type)
{ … }

static int iommufd_object_dec_wait_shortterm(struct iommufd_ctx *ictx,
					     struct iommufd_object *to_destroy)
{ … }

/*
 * Remove the given object id from the xarray if the only reference to the
 * object is held by the xarray.
 */
int iommufd_object_remove(struct iommufd_ctx *ictx,
			  struct iommufd_object *to_destroy, u32 id,
			  unsigned int flags)
{ … }

static int iommufd_destroy(struct iommufd_ucmd *ucmd)
{ … }

static int iommufd_fops_open(struct inode *inode, struct file *filp)
{ … }

static int iommufd_fops_release(struct inode *inode, struct file *filp)
{ … }

static int iommufd_option(struct iommufd_ucmd *ucmd)
{ … }

ucmd_buffer;

struct iommufd_ioctl_op { … };

#define IOCTL_OP(_ioctl, _fn, _struct, _last) …
static const struct iommufd_ioctl_op iommufd_ioctl_ops[] = …;

static long iommufd_fops_ioctl(struct file *filp, unsigned int cmd,
			       unsigned long arg)
{ … }

static const struct file_operations iommufd_fops = …;

/**
 * iommufd_ctx_get - Get a context reference
 * @ictx: Context to get
 *
 * The caller must already hold a valid reference to ictx.
 */
void iommufd_ctx_get(struct iommufd_ctx *ictx)
{ … }
EXPORT_SYMBOL_NS_GPL(…);

/**
 * iommufd_ctx_from_file - Acquires a reference to the iommufd context
 * @file: File to obtain the reference from
 *
 * Returns a pointer to the iommufd_ctx, otherwise ERR_PTR. The struct file
 * remains owned by the caller and the caller must still do fput. On success
 * the caller is responsible to call iommufd_ctx_put().
 */
struct iommufd_ctx *iommufd_ctx_from_file(struct file *file)
{ … }
EXPORT_SYMBOL_NS_GPL(…);

/**
 * iommufd_ctx_from_fd - Acquires a reference to the iommufd context
 * @fd: File descriptor to obtain the reference from
 *
 * Returns a pointer to the iommufd_ctx, otherwise ERR_PTR. On success
 * the caller is responsible to call iommufd_ctx_put().
 */
struct iommufd_ctx *iommufd_ctx_from_fd(int fd)
{ … }
EXPORT_SYMBOL_NS_GPL(…);

/**
 * iommufd_ctx_put - Put back a reference
 * @ictx: Context to put back
 */
void iommufd_ctx_put(struct iommufd_ctx *ictx)
{ … }
EXPORT_SYMBOL_NS_GPL(…);

static const struct iommufd_object_ops iommufd_object_ops[] = …;

static struct miscdevice iommu_misc_dev = …;


static struct miscdevice vfio_misc_dev = …;

static int __init iommufd_init(void)
{ … }

static void __exit iommufd_exit(void)
{ … }

module_init(…) …;
module_exit(iommufd_exit);

#if IS_ENABLED(CONFIG_IOMMUFD_VFIO_CONTAINER)
MODULE_ALIAS_MISCDEV(VFIO_MINOR);
MODULE_ALIAS("devname:vfio/vfio");
#endif
MODULE_IMPORT_NS(…);
MODULE_IMPORT_NS(…);
MODULE_DESCRIPTION(…) …;
MODULE_LICENSE(…) …;