linux-loongson/include/uapi/linux/vhost.h
Linus Torvalds 821c9e515d virtio, vhost: features, fixes
vhost can now support legacy threading
 	if enabled in Kconfig
 vsock memory allocation strategies for
 	large buffers have been improved,
 	reducing pressure on kmalloc
 vhost now supports the in-order feature
 	guest bits missed the merge window
 
 fixes, cleanups all over the place
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull virtio updates from Michael Tsirkin:

 - vhost can now support legacy threading if enabled in Kconfig

 - vsock memory allocation strategies for large buffers have been
   improved, reducing pressure on kmalloc

 - vhost now supports the in-order feature. guest bits missed the merge
   window.

 - fixes, cleanups all over the place

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (30 commits)
  vsock/virtio: Allocate nonlinear SKBs for handling large transmit buffers
  vsock/virtio: Rename virtio_vsock_skb_rx_put()
  vhost/vsock: Allocate nonlinear SKBs for handling large receive buffers
  vsock/virtio: Move SKB allocation lower-bound check to callers
  vsock/virtio: Rename virtio_vsock_alloc_skb()
  vsock/virtio: Resize receive buffers so that each SKB fits in a 4K page
  vsock/virtio: Move length check to callers of virtio_vsock_skb_rx_put()
  vsock/virtio: Validate length in packet header before skb_put()
  vhost/vsock: Avoid allocating arbitrarily-sized SKBs
  vhost_net: basic in_order support
  vhost: basic in order support
  vhost: fail early when __vhost_add_used() fails
  vhost: Reintroduce kthread API and add mode selection
  vdpa: Fix IDR memory leak in VDUSE module exit
  vdpa/mlx5: Fix release of uninitialized resources on error path
  vhost-scsi: Fix check for inline_sg_cnt exceeding preallocated limit
  virtio: virtio_dma_buf: fix missing parameter documentation
  vhost: Fix typos
  vhost: vringh: Remove unused functions
  vhost: vringh: Remove unused iotlb functions
  ...
2025-08-01 14:17:48 -07:00

274 lines
11 KiB
C

/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
#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)
/* Attach a vhost_worker created with VHOST_NEW_WORKER to one of the device's
* virtqueues.
*
* This will replace the virtqueue's existing worker. If the replaced worker
* is no longer attached to any virtqueues, it can be freed with
* VHOST_FREE_WORKER.
*/
#define VHOST_ATTACH_VRING_WORKER _IOW(VHOST_VIRTIO, 0x15, \
struct vhost_vring_worker)
/* Return the vring worker's ID */
#define VHOST_GET_VRING_WORKER _IOWR(VHOST_VIRTIO, 0x16, \
struct vhost_vring_worker)
/* The following ioctls use eventfd file descriptors to signal and poll
* for events. */
/* Set eventfd to poll for added buffers */
#define VHOST_SET_VRING_KICK _IOW(VHOST_VIRTIO, 0x20, struct vhost_vring_file)
/* Set eventfd to signal when buffers have beed used */
#define VHOST_SET_VRING_CALL _IOW(VHOST_VIRTIO, 0x21, struct vhost_vring_file)
/* Set eventfd to signal an error */
#define VHOST_SET_VRING_ERR _IOW(VHOST_VIRTIO, 0x22, struct vhost_vring_file)
/* Set busy loop timeout (in us) */
#define VHOST_SET_VRING_BUSYLOOP_TIMEOUT _IOW(VHOST_VIRTIO, 0x23, \
struct vhost_vring_state)
/* Get busy loop timeout (in us) */
#define VHOST_GET_VRING_BUSYLOOP_TIMEOUT _IOW(VHOST_VIRTIO, 0x24, \
struct vhost_vring_state)
/* Set or get vhost backend capability */
#define VHOST_SET_BACKEND_FEATURES _IOW(VHOST_VIRTIO, 0x25, __u64)
#define VHOST_GET_BACKEND_FEATURES _IOR(VHOST_VIRTIO, 0x26, __u64)
/* VHOST_NET specific defines */
/* Attach virtio net ring to a raw socket, or tap device.
* The socket must be already bound to an ethernet device, this device will be
* used for transmit. Pass fd -1 to unbind from the socket and the transmit
* device. This can be used to stop the ring (e.g. for migration). */
#define VHOST_NET_SET_BACKEND _IOW(VHOST_VIRTIO, 0x30, struct vhost_vring_file)
/* VHOST_SCSI specific defines */
#define VHOST_SCSI_SET_ENDPOINT _IOW(VHOST_VIRTIO, 0x40, struct vhost_scsi_target)
#define VHOST_SCSI_CLEAR_ENDPOINT _IOW(VHOST_VIRTIO, 0x41, struct vhost_scsi_target)
/* Changing this breaks userspace. */
#define VHOST_SCSI_GET_ABI_VERSION _IOW(VHOST_VIRTIO, 0x42, int)
/* Set and get the events missed flag */
#define VHOST_SCSI_SET_EVENTS_MISSED _IOW(VHOST_VIRTIO, 0x43, __u32)
#define VHOST_SCSI_GET_EVENTS_MISSED _IOW(VHOST_VIRTIO, 0x44, __u32)
/* VHOST_VSOCK specific defines */
#define VHOST_VSOCK_SET_GUEST_CID _IOW(VHOST_VIRTIO, 0x60, __u64)
#define VHOST_VSOCK_SET_RUNNING _IOW(VHOST_VIRTIO, 0x61, int)
/* VHOST_VDPA specific defines */
/* Get the device id. The device ids follow the same definition of
* the device id defined in virtio-spec.
*/
#define VHOST_VDPA_GET_DEVICE_ID _IOR(VHOST_VIRTIO, 0x70, __u32)
/* Get and set the status. The status bits follow the same definition
* of the device status defined in virtio-spec.
*/
#define VHOST_VDPA_GET_STATUS _IOR(VHOST_VIRTIO, 0x71, __u8)
#define VHOST_VDPA_SET_STATUS _IOW(VHOST_VIRTIO, 0x72, __u8)
/* Get and set the device config. The device config follows the same
* definition of the device config defined in virtio-spec.
*/
#define VHOST_VDPA_GET_CONFIG _IOR(VHOST_VIRTIO, 0x73, \
struct vhost_vdpa_config)
#define VHOST_VDPA_SET_CONFIG _IOW(VHOST_VIRTIO, 0x74, \
struct vhost_vdpa_config)
/* Enable/disable the ring. */
#define VHOST_VDPA_SET_VRING_ENABLE _IOW(VHOST_VIRTIO, 0x75, \
struct vhost_vring_state)
/* Get the max ring size. */
#define VHOST_VDPA_GET_VRING_NUM _IOR(VHOST_VIRTIO, 0x76, __u16)
/* Set event fd for config interrupt*/
#define VHOST_VDPA_SET_CONFIG_CALL _IOW(VHOST_VIRTIO, 0x77, int)
/* Get the valid iova range */
#define VHOST_VDPA_GET_IOVA_RANGE _IOR(VHOST_VIRTIO, 0x78, \
struct vhost_vdpa_iova_range)
/* Get the config size */
#define VHOST_VDPA_GET_CONFIG_SIZE _IOR(VHOST_VIRTIO, 0x79, __u32)
/* Get the number of address spaces. */
#define VHOST_VDPA_GET_AS_NUM _IOR(VHOST_VIRTIO, 0x7A, unsigned int)
/* Get the group for a virtqueue: read index, write group in num,
* The virtqueue index is stored in the index field of
* vhost_vring_state. The group for this specific virtqueue is
* returned via num field of vhost_vring_state.
*/
#define VHOST_VDPA_GET_VRING_GROUP _IOWR(VHOST_VIRTIO, 0x7B, \
struct vhost_vring_state)
/* Set the ASID for a virtqueue group. The group index is stored in
* the index field of vhost_vring_state, the ASID associated with this
* group is stored at num field of vhost_vring_state.
*/
#define VHOST_VDPA_SET_GROUP_ASID _IOW(VHOST_VIRTIO, 0x7C, \
struct vhost_vring_state)
/* Suspend a device so it does not process virtqueue requests anymore
*
* After the return of ioctl the device must preserve all the necessary state
* (the virtqueue vring base plus the possible device specific states) that is
* required for restoring in the future. The device must not change its
* configuration after that point.
*/
#define VHOST_VDPA_SUSPEND _IO(VHOST_VIRTIO, 0x7D)
/* Resume a device so it can resume processing virtqueue requests
*
* After the return of this ioctl the device will have restored all the
* necessary states and it is fully operational to continue processing the
* virtqueue descriptors.
*/
#define VHOST_VDPA_RESUME _IO(VHOST_VIRTIO, 0x7E)
/* Get the group for the descriptor table including driver & device areas
* of a virtqueue: read index, write group in num.
* The virtqueue index is stored in the index field of vhost_vring_state.
* The group ID of the descriptor table for this specific virtqueue
* is returned via num field of vhost_vring_state.
*/
#define VHOST_VDPA_GET_VRING_DESC_GROUP _IOWR(VHOST_VIRTIO, 0x7F, \
struct vhost_vring_state)
/* Get the count of all virtqueues */
#define VHOST_VDPA_GET_VQS_COUNT _IOR(VHOST_VIRTIO, 0x80, __u32)
/* Get the number of virtqueue groups. */
#define VHOST_VDPA_GET_GROUP_NUM _IOR(VHOST_VIRTIO, 0x81, __u32)
/* Get the queue size of a specific virtqueue.
* userspace set the vring index in vhost_vring_state.index
* kernel set the queue size in vhost_vring_state.num
*/
#define VHOST_VDPA_GET_VRING_SIZE _IOWR(VHOST_VIRTIO, 0x82, \
struct vhost_vring_state)
/* Extended features manipulation */
#define VHOST_GET_FEATURES_ARRAY _IOR(VHOST_VIRTIO, 0x83, \
struct vhost_features_array)
#define VHOST_SET_FEATURES_ARRAY _IOW(VHOST_VIRTIO, 0x83, \
struct vhost_features_array)
/* fork_owner values for vhost */
#define VHOST_FORK_OWNER_KTHREAD 0
#define VHOST_FORK_OWNER_TASK 1
/**
* VHOST_SET_FORK_FROM_OWNER - Set the fork_owner flag for the vhost device,
* This ioctl must called before VHOST_SET_OWNER.
* Only available when CONFIG_VHOST_ENABLE_FORK_OWNER_CONTROL=y
*
* @param fork_owner: An 8-bit value that determines the vhost thread mode
*
* When fork_owner is set to VHOST_FORK_OWNER_TASK(default value):
* - Vhost will create vhost worker as tasks forked from the owner,
* inheriting all of the owner's attributes.
*
* When fork_owner is set to VHOST_FORK_OWNER_KTHREAD:
* - Vhost will create vhost workers as kernel threads.
*/
#define VHOST_SET_FORK_FROM_OWNER _IOW(VHOST_VIRTIO, 0x83, __u8)
/**
* VHOST_GET_FORK_OWNER - Get the current fork_owner flag for the vhost device.
* Only available when CONFIG_VHOST_ENABLE_FORK_OWNER_CONTROL=y
*
* @return: An 8-bit value indicating the current thread mode.
*/
#define VHOST_GET_FORK_FROM_OWNER _IOR(VHOST_VIRTIO, 0x84, __u8)
#endif