tools/perf/trace/beauty/include/uapi/linux/vhost.h

Source file repositories/reference/linux-study-clean/tools/perf/trace/beauty/include/uapi/linux/vhost.h

File Facts

System
Linux kernel
Corpus path
tools/perf/trace/beauty/include/uapi/linux/vhost.h
Extension
.h
Size
11511 bytes
Lines
274
Domain
Support Tooling And Documentation
Bucket
tools
Inferred role
Support Tooling And Documentation: implementation source
Status
source implementation candidate

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

Detected Declarations

Annotated Snippet

#ifndef _LINUX_VHOST_H
#define _LINUX_VHOST_H
/* Userspace interface for in-kernel virtio accelerators. */

/* vhost is used to reduce the number of system calls involved in virtio.
 *
 * Existing virtio net code is used in the guest without modification.
 *
 * This header includes interface used by userspace hypervisor for
 * device configuration.
 */

#include <linux/vhost_types.h>
#include <linux/types.h>
#include <linux/ioctl.h>

#define VHOST_FILE_UNBIND -1

/* ioctls */

#define VHOST_VIRTIO 0xAF

/* Features bitmask for forward compatibility.  Transport bits are used for
 * vhost specific features. */
#define VHOST_GET_FEATURES	_IOR(VHOST_VIRTIO, 0x00, __u64)
#define VHOST_SET_FEATURES	_IOW(VHOST_VIRTIO, 0x00, __u64)

/* Set current process as the (exclusive) owner of this file descriptor.  This
 * must be called before any other vhost command.  Further calls to
 * VHOST_SET_OWNER fail until VHOST_RESET_OWNER is called. */
#define VHOST_SET_OWNER _IO(VHOST_VIRTIO, 0x01)
/* Give up ownership, and reset the device to default values.
 * Allows subsequent call to VHOST_SET_OWNER to succeed. */
#define VHOST_RESET_OWNER _IO(VHOST_VIRTIO, 0x02)

/* Set up/modify memory layout */
#define VHOST_SET_MEM_TABLE	_IOW(VHOST_VIRTIO, 0x03, struct vhost_memory)

/* Write logging setup. */
/* Memory writes can optionally be logged by setting bit at an offset
 * (calculated from the physical address) from specified log base.
 * The bit is set using an atomic 32 bit operation. */
/* Set base address for logging. */
#define VHOST_SET_LOG_BASE _IOW(VHOST_VIRTIO, 0x04, __u64)
/* Specify an eventfd file descriptor to signal on log write. */
#define VHOST_SET_LOG_FD _IOW(VHOST_VIRTIO, 0x07, int)
/* By default, a device gets one vhost_worker that its virtqueues share. This
 * command allows the owner of the device to create an additional vhost_worker
 * for the device. It can later be bound to 1 or more of its virtqueues using
 * the VHOST_ATTACH_VRING_WORKER command.
 *
 * This must be called after VHOST_SET_OWNER and the caller must be the owner
 * of the device. The new thread will inherit caller's cgroups and namespaces,
 * and will share the caller's memory space. The new thread will also be
 * counted against the caller's RLIMIT_NPROC value.
 *
 * The worker's ID used in other commands will be returned in
 * vhost_worker_state.
 */
#define VHOST_NEW_WORKER _IOR(VHOST_VIRTIO, 0x8, struct vhost_worker_state)
/* Free a worker created with VHOST_NEW_WORKER if it's not attached to any
 * virtqueue. If userspace is not able to call this for workers its created,
 * the kernel will free all the device's workers when the device is closed.
 */
#define VHOST_FREE_WORKER _IOW(VHOST_VIRTIO, 0x9, struct vhost_worker_state)

/* Ring setup. */
/* Set number of descriptors in ring. This parameter can not
 * be modified while ring is running (bound to a device). */
#define VHOST_SET_VRING_NUM _IOW(VHOST_VIRTIO, 0x10, struct vhost_vring_state)
/* Set addresses for the ring. */
#define VHOST_SET_VRING_ADDR _IOW(VHOST_VIRTIO, 0x11, struct vhost_vring_addr)
/* Base value where queue looks for available descriptors */
#define VHOST_SET_VRING_BASE _IOW(VHOST_VIRTIO, 0x12, struct vhost_vring_state)
/* Get accessor: reads index, writes value in num */
#define VHOST_GET_VRING_BASE _IOWR(VHOST_VIRTIO, 0x12, struct vhost_vring_state)

/* Set the vring byte order in num. Valid values are VHOST_VRING_LITTLE_ENDIAN
 * or VHOST_VRING_BIG_ENDIAN (other values return -EINVAL).
 * The byte order cannot be changed while the device is active: trying to do so
 * returns -EBUSY.
 * This is a legacy only API that is simply ignored when VIRTIO_F_VERSION_1 is
 * set.
 * Not all kernel configurations support this ioctl, but all configurations that
 * support SET also support GET.
 */
#define VHOST_VRING_LITTLE_ENDIAN 0
#define VHOST_VRING_BIG_ENDIAN 1
#define VHOST_SET_VRING_ENDIAN _IOW(VHOST_VIRTIO, 0x13, struct vhost_vring_state)
#define VHOST_GET_VRING_ENDIAN _IOW(VHOST_VIRTIO, 0x14, struct vhost_vring_state)

Annotation

Implementation Notes