https://github.com/torvalds/linux
Tip revision: 44c026a73be8038f03dbdeef028b642880cf1511 authored by Linus Torvalds on 21 May 2023, 21:05:48 UTC
Linux 6.4-rc3
Linux 6.4-rc3
Tip revision: 44c026a
vfio.h
/* SPDX-License-Identifier: GPL-2.0-only */
/*
* VFIO API definition
*
* Copyright (C) 2012 Red Hat, Inc. All rights reserved.
* Author: Alex Williamson <alex.williamson@redhat.com>
*/
#ifndef VFIO_H
#define VFIO_H
#include <linux/iommu.h>
#include <linux/mm.h>
#include <linux/workqueue.h>
#include <linux/poll.h>
#include <uapi/linux/vfio.h>
#include <linux/iova_bitmap.h>
struct kvm;
struct iommufd_ctx;
struct iommufd_device;
struct iommufd_access;
/*
* VFIO devices can be placed in a set, this allows all devices to share this
* structure and the VFIO core will provide a lock that is held around
* open_device()/close_device() for all devices in the set.
*/
struct vfio_device_set {
void *set_id;
struct mutex lock;
struct list_head device_list;
unsigned int device_count;
};
struct vfio_device {
struct device *dev;
const struct vfio_device_ops *ops;
/*
* mig_ops/log_ops is a static property of the vfio_device which must
* be set prior to registering the vfio_device.
*/
const struct vfio_migration_ops *mig_ops;
const struct vfio_log_ops *log_ops;
struct vfio_group *group;
struct vfio_device_set *dev_set;
struct list_head dev_set_list;
unsigned int migration_flags;
struct kvm *kvm;
/* Members below here are private, not for driver use */
unsigned int index;
struct device device; /* device.kref covers object life circle */
refcount_t refcount; /* user count on registered device*/
unsigned int open_count;
struct completion comp;
struct list_head group_next;
struct list_head iommu_entry;
struct iommufd_access *iommufd_access;
void (*put_kvm)(struct kvm *kvm);
#if IS_ENABLED(CONFIG_IOMMUFD)
struct iommufd_device *iommufd_device;
bool iommufd_attached;
#endif
};
/**
* struct vfio_device_ops - VFIO bus driver device callbacks
*
* @name: Name of the device driver.
* @init: initialize private fields in device structure
* @release: Reclaim private fields in device structure
* @bind_iommufd: Called when binding the device to an iommufd
* @unbind_iommufd: Opposite of bind_iommufd
* @attach_ioas: Called when attaching device to an IOAS/HWPT managed by the
* bound iommufd. Undo in unbind_iommufd.
* @open_device: Called when the first file descriptor is opened for this device
* @close_device: Opposite of open_device
* @read: Perform read(2) on device file descriptor
* @write: Perform write(2) on device file descriptor
* @ioctl: Perform ioctl(2) on device file descriptor, supporting VFIO_DEVICE_*
* operations documented below
* @mmap: Perform mmap(2) on a region of the device file descriptor
* @request: Request for the bus driver to release the device
* @match: Optional device name match callback (return: 0 for no-match, >0 for
* match, -errno for abort (ex. match with insufficient or incorrect
* additional args)
* @dma_unmap: Called when userspace unmaps IOVA from the container
* this device is attached to.
* @device_feature: Optional, fill in the VFIO_DEVICE_FEATURE ioctl
*/
struct vfio_device_ops {
char *name;
int (*init)(struct vfio_device *vdev);
void (*release)(struct vfio_device *vdev);
int (*bind_iommufd)(struct vfio_device *vdev,
struct iommufd_ctx *ictx, u32 *out_device_id);
void (*unbind_iommufd)(struct vfio_device *vdev);
int (*attach_ioas)(struct vfio_device *vdev, u32 *pt_id);
int (*open_device)(struct vfio_device *vdev);
void (*close_device)(struct vfio_device *vdev);
ssize_t (*read)(struct vfio_device *vdev, char __user *buf,
size_t count, loff_t *ppos);
ssize_t (*write)(struct vfio_device *vdev, const char __user *buf,
size_t count, loff_t *size);
long (*ioctl)(struct vfio_device *vdev, unsigned int cmd,
unsigned long arg);
int (*mmap)(struct vfio_device *vdev, struct vm_area_struct *vma);
void (*request)(struct vfio_device *vdev, unsigned int count);
int (*match)(struct vfio_device *vdev, char *buf);
void (*dma_unmap)(struct vfio_device *vdev, u64 iova, u64 length);
int (*device_feature)(struct vfio_device *device, u32 flags,
void __user *arg, size_t argsz);
};
#if IS_ENABLED(CONFIG_IOMMUFD)
int vfio_iommufd_physical_bind(struct vfio_device *vdev,
struct iommufd_ctx *ictx, u32 *out_device_id);
void vfio_iommufd_physical_unbind(struct vfio_device *vdev);
int vfio_iommufd_physical_attach_ioas(struct vfio_device *vdev, u32 *pt_id);
int vfio_iommufd_emulated_bind(struct vfio_device *vdev,
struct iommufd_ctx *ictx, u32 *out_device_id);
void vfio_iommufd_emulated_unbind(struct vfio_device *vdev);
int vfio_iommufd_emulated_attach_ioas(struct vfio_device *vdev, u32 *pt_id);
#else
#define vfio_iommufd_physical_bind \
((int (*)(struct vfio_device *vdev, struct iommufd_ctx *ictx, \
u32 *out_device_id)) NULL)
#define vfio_iommufd_physical_unbind \
((void (*)(struct vfio_device *vdev)) NULL)
#define vfio_iommufd_physical_attach_ioas \
((int (*)(struct vfio_device *vdev, u32 *pt_id)) NULL)
#define vfio_iommufd_emulated_bind \
((int (*)(struct vfio_device *vdev, struct iommufd_ctx *ictx, \
u32 *out_device_id)) NULL)
#define vfio_iommufd_emulated_unbind \
((void (*)(struct vfio_device *vdev)) NULL)
#define vfio_iommufd_emulated_attach_ioas \
((int (*)(struct vfio_device *vdev, u32 *pt_id)) NULL)
#endif
/**
* struct vfio_migration_ops - VFIO bus device driver migration callbacks
*
* @migration_set_state: Optional callback to change the migration state for
* devices that support migration. It's mandatory for
* VFIO_DEVICE_FEATURE_MIGRATION migration support.
* The returned FD is used for data transfer according to the FSM
* definition. The driver is responsible to ensure that FD reaches end
* of stream or error whenever the migration FSM leaves a data transfer
* state or before close_device() returns.
* @migration_get_state: Optional callback to get the migration state for
* devices that support migration. It's mandatory for
* VFIO_DEVICE_FEATURE_MIGRATION migration support.
* @migration_get_data_size: Optional callback to get the estimated data
* length that will be required to complete stop copy. It's mandatory for
* VFIO_DEVICE_FEATURE_MIGRATION migration support.
*/
struct vfio_migration_ops {
struct file *(*migration_set_state)(
struct vfio_device *device,
enum vfio_device_mig_state new_state);
int (*migration_get_state)(struct vfio_device *device,
enum vfio_device_mig_state *curr_state);
int (*migration_get_data_size)(struct vfio_device *device,
unsigned long *stop_copy_length);
};
/**
* struct vfio_log_ops - VFIO bus device driver logging callbacks
*
* @log_start: Optional callback to ask the device start DMA logging.
* @log_stop: Optional callback to ask the device stop DMA logging.
* @log_read_and_clear: Optional callback to ask the device read
* and clear the dirty DMAs in some given range.
*
* The vfio core implementation of the DEVICE_FEATURE_DMA_LOGGING_ set
* of features does not track logging state relative to the device,
* therefore the device implementation of vfio_log_ops must handle
* arbitrary user requests. This includes rejecting subsequent calls
* to log_start without an intervening log_stop, as well as graceful
* handling of log_stop and log_read_and_clear from invalid states.
*/
struct vfio_log_ops {
int (*log_start)(struct vfio_device *device,
struct rb_root_cached *ranges, u32 nnodes, u64 *page_size);
int (*log_stop)(struct vfio_device *device);
int (*log_read_and_clear)(struct vfio_device *device,
unsigned long iova, unsigned long length,
struct iova_bitmap *dirty);
};
/**
* vfio_check_feature - Validate user input for the VFIO_DEVICE_FEATURE ioctl
* @flags: Arg from the device_feature op
* @argsz: Arg from the device_feature op
* @supported_ops: Combination of VFIO_DEVICE_FEATURE_GET and SET the driver
* supports
* @minsz: Minimum data size the driver accepts
*
* For use in a driver's device_feature op. Checks that the inputs to the
* VFIO_DEVICE_FEATURE ioctl are correct for the driver's feature. Returns 1 if
* the driver should execute the get or set, otherwise the relevant
* value should be returned.
*/
static inline int vfio_check_feature(u32 flags, size_t argsz, u32 supported_ops,
size_t minsz)
{
if ((flags & (VFIO_DEVICE_FEATURE_GET | VFIO_DEVICE_FEATURE_SET)) &
~supported_ops)
return -EINVAL;
if (flags & VFIO_DEVICE_FEATURE_PROBE)
return 0;
/* Without PROBE one of GET or SET must be requested */
if (!(flags & (VFIO_DEVICE_FEATURE_GET | VFIO_DEVICE_FEATURE_SET)))
return -EINVAL;
if (argsz < minsz)
return -EINVAL;
return 1;
}
struct vfio_device *_vfio_alloc_device(size_t size, struct device *dev,
const struct vfio_device_ops *ops);
#define vfio_alloc_device(dev_struct, member, dev, ops) \
container_of(_vfio_alloc_device(sizeof(struct dev_struct) + \
BUILD_BUG_ON_ZERO(offsetof( \
struct dev_struct, member)), \
dev, ops), \
struct dev_struct, member)
static inline void vfio_put_device(struct vfio_device *device)
{
put_device(&device->device);
}
int vfio_register_group_dev(struct vfio_device *device);
int vfio_register_emulated_iommu_dev(struct vfio_device *device);
void vfio_unregister_group_dev(struct vfio_device *device);
int vfio_assign_device_set(struct vfio_device *device, void *set_id);
unsigned int vfio_device_set_open_count(struct vfio_device_set *dev_set);
int vfio_mig_get_next_state(struct vfio_device *device,
enum vfio_device_mig_state cur_fsm,
enum vfio_device_mig_state new_fsm,
enum vfio_device_mig_state *next_fsm);
/*
* External user API
*/
struct iommu_group *vfio_file_iommu_group(struct file *file);
bool vfio_file_is_group(struct file *file);
bool vfio_file_enforced_coherent(struct file *file);
void vfio_file_set_kvm(struct file *file, struct kvm *kvm);
bool vfio_file_has_dev(struct file *file, struct vfio_device *device);
#define VFIO_PIN_PAGES_MAX_ENTRIES (PAGE_SIZE/sizeof(unsigned long))
int vfio_pin_pages(struct vfio_device *device, dma_addr_t iova,
int npage, int prot, struct page **pages);
void vfio_unpin_pages(struct vfio_device *device, dma_addr_t iova, int npage);
int vfio_dma_rw(struct vfio_device *device, dma_addr_t iova,
void *data, size_t len, bool write);
/*
* Sub-module helpers
*/
struct vfio_info_cap {
struct vfio_info_cap_header *buf;
size_t size;
};
struct vfio_info_cap_header *vfio_info_cap_add(struct vfio_info_cap *caps,
size_t size, u16 id,
u16 version);
void vfio_info_cap_shift(struct vfio_info_cap *caps, size_t offset);
int vfio_info_add_capability(struct vfio_info_cap *caps,
struct vfio_info_cap_header *cap, size_t size);
int vfio_set_irqs_validate_and_prepare(struct vfio_irq_set *hdr,
int num_irqs, int max_irq_type,
size_t *data_size);
/*
* IRQfd - generic
*/
struct virqfd {
void *opaque;
struct eventfd_ctx *eventfd;
int (*handler)(void *, void *);
void (*thread)(void *, void *);
void *data;
struct work_struct inject;
wait_queue_entry_t wait;
poll_table pt;
struct work_struct shutdown;
struct virqfd **pvirqfd;
};
int vfio_virqfd_enable(void *opaque, int (*handler)(void *, void *),
void (*thread)(void *, void *), void *data,
struct virqfd **pvirqfd, int fd);
void vfio_virqfd_disable(struct virqfd **pvirqfd);
#endif /* VFIO_H */