/* SPDX-License-Identifier: BSD-3-Clause
* Copyright(c) 2010-2017 Intel Corporation
*/
#ifndef _RTE_VHOST_H_
#define _RTE_VHOST_H_
/**
* @file
* Interface to vhost-user
*/
#include <stdbool.h>
#include <stdint.h>
#include <sys/eventfd.h>
#include <rte_memory.h>
#include <rte_mempool.h>
#ifdef __cplusplus
extern "C" {
#endif
#ifndef __cplusplus
/* These are not C++-aware. */
#include <linux/vhost.h>
#include <linux/virtio_ring.h>
#include <linux/virtio_net.h>
#endif
#define RTE_VHOST_USER_CLIENT (1ULL << 0)
#define RTE_VHOST_USER_NO_RECONNECT (1ULL << 1)
#define RTE_VHOST_USER_RESERVED_1 (1ULL << 2)
#define RTE_VHOST_USER_IOMMU_SUPPORT (1ULL << 3)
#define RTE_VHOST_USER_POSTCOPY_SUPPORT (1ULL << 4)
/* support mbuf with external buffer attached */
#define RTE_VHOST_USER_EXTBUF_SUPPORT (1ULL << 5)
/* support only linear buffers (no chained mbufs) */
#define RTE_VHOST_USER_LINEARBUF_SUPPORT (1ULL << 6)
#define RTE_VHOST_USER_ASYNC_COPY (1ULL << 7)
#define RTE_VHOST_USER_NET_COMPLIANT_OL_FLAGS (1ULL << 8)
/* Features. */
#ifndef VIRTIO_NET_F_GUEST_ANNOUNCE
#define VIRTIO_NET_F_GUEST_ANNOUNCE 21
#endif
#ifndef VIRTIO_NET_F_MQ
#define VIRTIO_NET_F_MQ 22
#endif
#ifndef VIRTIO_NET_F_MTU
#define VIRTIO_NET_F_MTU 3
#endif
#ifndef VIRTIO_F_ANY_LAYOUT
#define VIRTIO_F_ANY_LAYOUT 27
#endif
/** Protocol features. */
#ifndef VHOST_USER_PROTOCOL_F_MQ
#define VHOST_USER_PROTOCOL_F_MQ 0
#endif
#ifndef VHOST_USER_PROTOCOL_F_LOG_SHMFD
#define VHOST_USER_PROTOCOL_F_LOG_SHMFD 1
#endif
#ifndef VHOST_USER_PROTOCOL_F_RARP
#define VHOST_USER_PROTOCOL_F_RARP 2
#endif
#ifndef VHOST_USER_PROTOCOL_F_REPLY_ACK
#define VHOST_USER_PROTOCOL_F_REPLY_ACK 3
#endif
#ifndef VHOST_USER_PROTOCOL_F_NET_MTU
#define VHOST_USER_PROTOCOL_F_NET_MTU 4
#endif
#ifndef VHOST_USER_PROTOCOL_F_SLAVE_REQ
#define VHOST_USER_PROTOCOL_F_SLAVE_REQ 5
#endif
#ifndef VHOST_USER_PROTOCOL_F_CRYPTO_SESSION
#define VHOST_USER_PROTOCOL_F_CRYPTO_SESSION 7
#endif
#ifndef VHOST_USER_PROTOCOL_F_PAGEFAULT
#define VHOST_USER_PROTOCOL_F_PAGEFAULT 8
#endif
#ifndef VHOST_USER_PROTOCOL_F_CONFIG
#define VHOST_USER_PROTOCOL_F_CONFIG 9
#endif
#ifndef VHOST_USER_PROTOCOL_F_SLAVE_SEND_FD
#define VHOST_USER_PROTOCOL_F_SLAVE_SEND_FD 10
#endif
#ifndef VHOST_USER_PROTOCOL_F_HOST_NOTIFIER
#define VHOST_USER_PROTOCOL_F_HOST_NOTIFIER 11
#endif
#ifndef VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD
#define VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD 12
#endif
#ifndef VHOST_USER_PROTOCOL_F_STATUS
#define VHOST_USER_PROTOCOL_F_STATUS 16
#endif
/** Indicate whether protocol features negotiation is supported. */
#ifndef VHOST_USER_F_PROTOCOL_FEATURES
#define VHOST_USER_F_PROTOCOL_FEATURES 30
#endif
struct rte_vdpa_device;
/**
* Information relating to memory regions including offsets to
* addresses in QEMUs memory file.
*/
struct rte_vhost_mem_region {
uint64_t guest_phys_addr;
uint64_t guest_user_addr;
uint64_t host_user_addr;
uint64_t size;
void *mmap_addr;
uint64_t mmap_size;
int fd;
};
/**
* Memory structure includes region and mapping information.
*/
struct rte_vhost_memory {
uint32_t nregions;
struct rte_vhost_mem_region regions[];
};
struct rte_vhost_inflight_desc_split {
uint8_t inflight;
uint8_t padding[5];
uint16_t next;
uint64_t counter;
};
struct rte_vhost_inflight_info_split {
uint64_t features;
uint16_t version;
uint16_t desc_num;
uint16_t last_inflight_io;
uint16_t used_idx;
struct rte_vhost_inflight_desc_split desc[0];
};
struct rte_vhost_inflight_desc_packed {
uint8_t inflight;
uint8_t padding;
uint16_t next;
uint16_t last;
uint16_t num;
uint64_t counter;
uint16_t id;
uint16_t flags;
uint32_t len;
uint64_t addr;
};
struct rte_vhost_inflight_info_packed {
uint64_t features;
uint16_t version;
uint16_t desc_num;
uint16_t free_head;
uint16_t old_free_head;
uint16_t used_idx;
uint16_t old_used_idx;
uint8_t used_wrap_counter;
uint8_t old_used_wrap_counter;
uint8_t padding[7];
struct rte_vhost_inflight_desc_packed desc[0];
};
struct rte_vhost_resubmit_desc {
uint16_t index;
uint64_t counter;
};
struct rte_vhost_resubmit_info {
struct rte_vhost_resubmit_desc *resubmit_list;
uint16_t resubmit_num;
};
struct rte_vhost_ring_inflight {
union {
struct rte_vhost_inflight_info_split *inflight_split;
struct rte_vhost_inflight_info_packed *inflight_packed;
};
struct rte_vhost_resubmit_info *resubmit_inflight;
};
struct rte_vhost_vring {
union {
struct vring_desc *desc;
struct vring_packed_desc *desc_packed;
};
union {
struct vring_avail *avail;
struct vring_packed_desc_event *driver_event;
};
union {
struct vring_used *used;
struct vring_packed_desc_event *device_event;
};
uint64_t log_guest_addr;
/** Deprecated, use rte_vhost_vring_call() instead. */
int callfd;
int kickfd;
uint16_t size;
};
/**
* Possible results of the vhost user message handling callbacks
*/
enum rte_vhost_msg_result {
/* Message handling failed */
RTE_VHOST_MSG_RESULT_ERR = -1,
/* Message handling successful */
RTE_VHOST_MSG_RESULT_OK = 0,
/* Message handling successful and reply prepared */
RTE_VHOST_MSG_RESULT_REPLY = 1,
/* Message not handled */
RTE_VHOST_MSG_RESULT_NOT_HANDLED,
};
/**
* Function prototype for the vhost backend to handle specific vhost user
* messages.
*
* @param vid
* vhost device id
* @param msg
* Message pointer.
* @return
* RTE_VHOST_MSG_RESULT_OK on success,
* RTE_VHOST_MSG_RESULT_REPLY on success with reply,
* RTE_VHOST_MSG_RESULT_ERR on failure,
* RTE_VHOST_MSG_RESULT_NOT_HANDLED if message was not handled.
*/
typedef enum rte_vhost_msg_result (*rte_vhost_msg_handle)(int vid, void *msg);
/**
* Optional vhost user message handlers.
*/
struct rte_vhost_user_extern_ops {
/* Called prior to the master message handling. */
rte_vhost_msg_handle pre_msg_handle;
/* Called after the master message handling. */
rte_vhost_msg_handle post_msg_handle;
};
/**
* Device and vring operations.
*/
struct rte_vhost_device_ops {
int (*new_device)(int vid); /**< Add device. */
void (*destroy_device)(int vid); /**< Remove device. */
int (*vring_state_changed)(int vid, uint16_t queue_id, int enable); /**< triggered when a vring is enabled or disabled */
/**
* Features could be changed after the feature negotiation.
* For example, VHOST_F_LOG_ALL will be set/cleared at the
* start/end of live migration, respectively. This callback
* is used to inform the application on such change.
*/
int (*features_changed)(int vid, uint64_t features);
int (*new_connection)(int vid);
void (*destroy_connection)(int vid);
/**
* This callback gets called each time a guest gets notified
* about waiting packets. This is the interrupt handling through
* the eventfd_write(callfd), which can be used for counting these
* "slow" syscalls.
*/
void (*guest_notified)(int vid);
void *reserved[1]; /**< Reserved for future extension */
};
/**
* Power monitor condition.
*/
struct rte_vhost_power_monitor_cond {
/**< Address to monitor for changes */
volatile void *addr;
/**< If the `mask` is non-zero, location pointed
* to by `addr` will be read and masked, then
* compared with this value.
*/
uint64_t val;
/**< 64-bit mask to extract value read from `addr` */
uint64_t mask;
/**< Data size (in bytes) that will be read from the
* monitored memory location (`addr`).
*/
uint8_t size;
/**< If 1, and masked value that read from 'addr' equals
* 'val', the driver should skip core sleep. If 0, and
* masked value that read from 'addr' does not equal 'val',
* the driver should skip core sleep.
*/
uint8_t match;
};
/**
* Convert guest physical address to host virtual address
*
* This function is deprecated because unsafe.
* New rte_vhost_va_from_guest_pa() should be used instead to ensure
* guest physical ranges are fully and contiguously mapped into
* process virtual address space.
*
* @param mem
* the guest memory regions
* @param gpa
* the guest physical address for querying
* @return
* the host virtual address on success, 0 on failure
*/
__rte_deprecated
static __rte_always_inline uint64_t
rte_vhost_gpa_to_vva(struct rte_vhost_memory *mem, uint64_t gpa)
{
struct rte_vhost_mem_region *reg;
uint32_t i;
for (i = 0; i < mem->nregions; i++) {
reg = &mem->regions[i];
if (gpa >= reg->guest_phys_addr &&
gpa < reg->guest_phys_addr + reg->size) {
return gpa - reg->guest_phys_addr +
reg->host_user_addr;
}
}
return 0;
}
/**
* Convert guest physical address to host virtual address safely
*
* This variant of rte_vhost_gpa_to_vva() takes care all the
* requested length is mapped and contiguous in process address
* space.
*
* @param mem
* the guest memory regions
* @param gpa
* the guest physical address for querying
* @param len
* the size of the requested area to map, updated with actual size mapped
* @return
* the host virtual address on success, 0 on failure
*/
static __rte_always_inline uint64_t
rte_vhost_va_from_guest_pa(struct rte_vhost_memory *mem,
uint64_t gpa, uint64_t *len)
{
struct rte_vhost_mem_region *r;
uint32_t i;
for (i = 0; i < mem->nregions; i++) {
r = &mem->regions[i];
if (gpa >= r->guest_phys_addr &&
gpa < r->guest_phys_addr + r->size) {
if (unlikely(*len > r->guest_phys_addr + r->size - gpa))
*len = r->guest_phys_addr + r->size - gpa;
return gpa - r->guest_phys_addr +
r->host_user_addr;
}
}
*len = 0;
return 0;
}
#define RTE_VHOST_NEED_LOG(features) ((features) & (1ULL << VHOST_F_LOG_ALL))
/**
* Log the memory write start with given address.
*
* This function only need be invoked when the live migration starts.
* Therefore, we won't need call it at all in the most of time. For
* making the performance impact be minimum, it's suggested to do a
* check before calling it:
*
* if (unlikely(RTE_VHOST_NEED_LOG(features)))
* rte_vhost_log_write(vid, addr, len);
*
* @param vid
* vhost device ID
* @param addr
* the starting address for write (in guest physical address space)
* @param len
* the length to write
*/
void rte_vhost_log_write(int vid, uint64_t addr, uint64_t len);
/**
* Log the used ring update start at given offset.
*
* Same as rte_vhost_log_write, it's suggested to do a check before
* calling it:
*
* if (unlikely(RTE_VHOST_NEED_LOG(features)))
* rte_vhost_log_used_vring(vid, vring_idx, offset, len);
*
* @param vid
* vhost device ID
* @param vring_idx
* the vring index
* @param offset
* the offset inside the used ring
* @param len
* the length to write
*/
void rte_vhost_log_used_vring(int vid, uint16_t vring_idx,
uint64_t offset, uint64_t len);
int rte_vhost_enable_guest_notification(int vid, uint16_t queue_id, int enable);
/**
* Register vhost driver. path could be different for multiple
* instance support.
*/
int rte_vhost_driver_register(const char *path, uint64_t flags);
/* Unregister vhost driver. This is only meaningful to vhost user. */
int rte_vhost_driver_unregister(const char *path);
/**
* Set the vdpa device id, enforce single connection per socket
*
* @param path
* The vhost-user socket file path
* @param dev
* vDPA device pointer
* @return
* 0 on success, -1 on failure
*/
int
rte_vhost_driver_attach_vdpa_device(const char *path,
struct rte_vdpa_device *dev);
/**
* Unset the vdpa device id
*
* @param path
* The vhost-user socket file path
* @return
* 0 on success, -1 on failure
*/
int
rte_vhost_driver_detach_vdpa_device(const char *path);
/**
* Get the device id
*
* @param path
* The vhost-user socket file path
* @return
* vDPA device pointer, NULL on failure
*/
struct rte_vdpa_device *
rte_vhost_driver_get_vdpa_device(const char *path);
/**
* Set the feature bits the vhost-user driver supports.
*
* @param path
* The vhost-user socket file path
* @param features
* Supported features
* @return
* 0 on success, -1 on failure
*/
int rte_vhost_driver_set_features(const char *path, uint64_t features);
/**
* Enable vhost-user driver features.
*
* Note that
* - the param features should be a subset of the feature bits provided
* by rte_vhost_driver_set_features().
* - it must be invoked before vhost-user negotiation starts.
*
* @param path
* The vhost-user socket file path
* @param features
* Features to enable
* @return
* 0 on success, -1 on failure
*/
int rte_vhost_driver_enable_features(const char *path, uint64_t features);
/**
* Disable vhost-user driver features.
*
* The two notes at rte_vhost_driver_enable_features() also apply here.
*
* @param path
* The vhost-user socket file path
* @param features
* Features to disable
* @return
* 0 on success, -1 on failure
*/
int rte_vhost_driver_disable_features(const char *path, uint64_t features);
/**
* Get the feature bits before feature negotiation.
*
* @param path
* The vhost-user socket file path
* @param features
* A pointer to store the queried feature bits
* @return
* 0 on success, -1 on failure
*/
int rte_vhost_driver_get_features(const char *path, uint64_t *features);
/**
* Set the protocol feature bits before feature negotiation.
*
* @param path
* The vhost-user socket file path
* @param protocol_features
* Supported protocol features
* @return
* 0 on success, -1 on failure
*/
int
rte_vhost_driver_set_protocol_features(const char *path,
uint64_t protocol_features);
/**
* Get the protocol feature bits before feature negotiation.
*
* @param path
* The vhost-user socket file path
* @param protocol_features
* A pointer to store the queried protocol feature bits
* @return
* 0 on success, -1 on failure
*/
int
rte_vhost_driver_get_protocol_features(const char *path,
uint64_t *protocol_features);
/**
* Get the queue number bits before feature negotiation.
*
* @param path
* The vhost-user socket file path
* @param queue_num
* A pointer to store the queried queue number bits
* @return
* 0 on success, -1 on failure
*/
int
rte_vhost_driver_get_queue_num(const char *path, uint32_t *queue_num);
/**
* Get the feature bits after negotiation
*
* @param vid
* Vhost device ID
* @param features
* A pointer to store the queried feature bits
* @return
* 0 on success, -1 on failure
*/
int rte_vhost_get_negotiated_features(int vid, uint64_t *features);
/**
* Get the protocol feature bits after negotiation
*
* @param vid
* Vhost device ID
* @param protocol_features
* A pointer to store the queried protocol feature bits
* @return
* 0 on success, -1 on failure
*/
__rte_experimental
int
rte_vhost_get_negotiated_protocol_features(int vid,
uint64_t *protocol_features);
/* Register callbacks. */
int rte_vhost_driver_callback_register(const char *path,
struct rte_vhost_device_ops const * const ops);
/**
*
* Start the vhost-user driver.
*
* This function triggers the vhost-user negotiation.
*
* @param path
* The vhost-user socket file path
* @return
* 0 on success, -1 on failure
*/
int rte_vhost_driver_start(const char *path);
/**
* Get the MTU value of the device if set in QEMU.
*
* @param vid
* virtio-net device ID
* @param mtu
* The variable to store the MTU value
*
* @return
* 0: success
* -EAGAIN: device not yet started
* -ENOTSUP: device does not support MTU feature
*/
int rte_vhost_get_mtu(int vid, uint16_t *mtu);
/**
* Get the numa node from which the virtio net device's memory
* is allocated.
*
* @param vid
* vhost device ID
*
* @return
* The numa node, -1 on failure
*/
int rte_vhost_get_numa_node(int vid);
/**
* @deprecated
* Get the number of queues the device supports.
*
* Note this function is deprecated, as it returns a queue pair number,
* which is vhost specific. Instead, rte_vhost_get_vring_num should
* be used.
*
* @param vid
* vhost device ID
*
* @return
* The number of queues, 0 on failure
*/
__rte_deprecated
uint32_t rte_vhost_get_queue_num(int vid);
/**
* Get the number of vrings the device supports.
*
* @param vid
* vhost device ID
*
* @return
* The number of vrings, 0 on failure
*/
uint16_t rte_vhost_get_vring_num(int vid);
/**
* Get the virtio net device's ifname, which is the vhost-user socket
* file path.
*
* @param vid
* vhost device ID
* @param buf
* The buffer to stored the queried ifname
* @param len
* The length of buf
*
* @return
* 0 on success, -1 on failure
*/
int rte_vhost_get_ifname(int vid, char *buf, size_t len);
/**
* Get how many avail entries are left in the queue
*
* @param vid
* vhost device ID
* @param queue_id
* virtio queue index
*
* @return
* num of avail entries left
*/
uint16_t rte_vhost_avail_entries(int vid, uint16_t queue_id);
struct rte_mbuf;
struct rte_mempool;
/**
* This function adds buffers to the virtio devices RX virtqueue. Buffers can
* be received from the physical port or from another virtual device. A packet
* count is returned to indicate the number of packets that were successfully
* added to the RX queue.
* @param vid
* vhost device ID
* @param queue_id
* virtio queue index in mq case
* @param pkts
* array to contain packets to be enqueued
* @param count
* packets num to be enqueued
* @return
* num of packets enqueued
*/
uint16_t rte_vhost_enqueue_burst(int vid, uint16_t queue_id,
struct rte_mbuf **pkts, uint16_t count);
/**
* This function gets guest buffers from the virtio device TX virtqueue,
* construct host mbufs, copies guest buffer content to host mbufs and
* store them in pkts to be processed.
* @param vid
* vhost device ID
* @param queue_id
* virtio queue index in mq case
* @param mbuf_pool
* mbuf_pool where host mbuf is allocated.
* @param pkts
* array to contain packets to be dequeued
* @param count
* packets num to be dequeued
* @return
* num of packets dequeued
*/
uint16_t rte_vhost_dequeue_burst(int vid, uint16_t queue_id,
struct rte_mempool *mbuf_pool, struct rte_mbuf **pkts, uint16_t count);
/**
* Get guest mem table: a list of memory regions.
*
* An rte_vhost_vhost_memory object will be allocated internally, to hold the
* guest memory regions. Application should free it at destroy_device()
* callback.
*
* @param vid
* vhost device ID
* @param mem
* To store the returned mem regions
* @return
* 0 on success, -1 on failure
*/
int rte_vhost_get_mem_table(int vid, struct rte_vhost_memory **mem);
/**
* Get guest vring info, including the vring address, vring size, etc.
*
* @param vid
* vhost device ID
* @param vring_idx
* vring index
* @param vring
* the structure to hold the requested vring info
* @return
* 0 on success, -1 on failure
*/
int rte_vhost_get_vhost_vring(int vid, uint16_t vring_idx,
struct rte_vhost_vring *vring);
/**
* Get guest inflight vring info, including inflight ring and resubmit list.
*
* @param vid
* vhost device ID
* @param vring_idx
* vring index
* @param vring
* the structure to hold the requested inflight vring info
* @return
* 0 on success, -1 on failure
*/
int
rte_vhost_get_vhost_ring_inflight(int vid, uint16_t vring_idx,
struct rte_vhost_ring_inflight *vring);
/**
* Set split inflight descriptor.
*
* This function save descriptors that has been consumed in available
* ring
*
* @param vid
* vhost device ID
* @param vring_idx
* vring index
* @param idx
* inflight entry index
* @return
* 0 on success, -1 on failure
*/
int
rte_vhost_set_inflight_desc_split(int vid, uint16_t vring_idx,
uint16_t idx);
/**
* Set packed inflight descriptor and get corresponding inflight entry
*
* This function save descriptors that has been consumed
*
* @param vid
* vhost device ID
* @param vring_idx
* vring index
* @param head
* head of descriptors
* @param last
* last of descriptors
* @param inflight_entry
* corresponding inflight entry
* @return
* 0 on success, -1 on failure
*/
int
rte_vhost_set_inflight_desc_packed(int vid, uint16_t vring_idx,
uint16_t head, uint16_t last, uint16_t *inflight_entry);
/**
* Save the head of list that the last batch of used descriptors.
*
* @param vid
* vhost device ID
* @param vring_idx
* vring index
* @param idx
* descriptor entry index
* @return
* 0 on success, -1 on failure
*/
int
rte_vhost_set_last_inflight_io_split(int vid,
uint16_t vring_idx, uint16_t idx);
/**
* Update the inflight free_head, used_idx and used_wrap_counter.
*
* This function will update status first before updating descriptors
* to used
*
* @param vid
* vhost device ID
* @param vring_idx
* vring index
* @param head
* head of descriptors
* @return
* 0 on success, -1 on failure
*/
int
rte_vhost_set_last_inflight_io_packed(int vid,
uint16_t vring_idx, uint16_t head);
/**
* Clear the split inflight status.
*
* @param vid
* vhost device ID
* @param vring_idx
* vring index
* @param last_used_idx
* last used idx of used ring
* @param idx
* inflight entry index
* @return
* 0 on success, -1 on failure
*/
int
rte_vhost_clr_inflight_desc_split(int vid, uint16_t vring_idx,
uint16_t last_used_idx, uint16_t idx);
/**
* Clear the packed inflight status.
*
* @param vid
* vhost device ID
* @param vring_idx
* vring index
* @param head
* inflight entry index
* @return
* 0 on success, -1 on failure
*/
int
rte_vhost_clr_inflight_desc_packed(int vid, uint16_t vring_idx,
uint16_t head);
/**
* Notify the guest that used descriptors have been added to the vring. This
* function acts as a memory barrier.
*
* @param vid
* vhost device ID
* @param vring_idx
* vring index
* @return
* 0 on success, -1 on failure
*/
int rte_vhost_vring_call(int vid, uint16_t vring_idx);
/**
* Get vhost RX queue avail count.
*
* @param vid
* vhost device ID
* @param qid
* virtio queue index in mq case
* @return
* num of desc available
*/
uint32_t rte_vhost_rx_queue_count(int vid, uint16_t qid);
/**
* Get power monitor address of the vhost device
*
* @param vid
* vhost device ID
* @param queue_id
* vhost queue ID
* @param pmc
* power monitor condition
* @return
* 0 on success, -1 on failure
*/
__rte_experimental
int
rte_vhost_get_monitor_addr(int vid, uint16_t queue_id,
struct rte_vhost_power_monitor_cond *pmc);
/**
* Get log base and log size of the vhost device
*
* @param vid
* vhost device ID
* @param log_base
* vhost log base
* @param log_size
* vhost log size
* @return
* 0 on success, -1 on failure
*/
int
rte_vhost_get_log_base(int vid, uint64_t *log_base, uint64_t *log_size);
/**
* Get last_avail/used_idx of the vhost virtqueue
*
* @param vid
* vhost device ID
* @param queue_id
* vhost queue index
* @param last_avail_idx
* vhost last_avail_idx to get
* @param last_used_idx
* vhost last_used_idx to get
* @return
* 0 on success, -1 on failure
*/
int
rte_vhost_get_vring_base(int vid, uint16_t queue_id,
uint16_t *last_avail_idx, uint16_t *last_used_idx);
/**
* Get last_avail/last_used of the vhost virtqueue
*
* This function is designed for the reconnection and it's specific for
* the packed ring as we can get the two parameters from the inflight
* queueregion
*
* @param vid
* vhost device ID
* @param queue_id
* vhost queue index
* @param last_avail_idx
* vhost last_avail_idx to get
* @param last_used_idx
* vhost last_used_idx to get
* @return
* 0 on success, -1 on failure
*/
int
rte_vhost_get_vring_base_from_inflight(int vid,
uint16_t queue_id, uint16_t *last_avail_idx, uint16_t *last_used_idx);
/**
* Set last_avail/used_idx of the vhost virtqueue
*
* @param vid
* vhost device ID
* @param queue_id
* vhost queue index
* @param last_avail_idx
* last_avail_idx to set
* @param last_used_idx
* last_used_idx to set
* @return
* 0 on success, -1 on failure
*/
int
rte_vhost_set_vring_base(int vid, uint16_t queue_id,
uint16_t last_avail_idx, uint16_t last_used_idx);
/**
* Register external message handling callbacks
*
* @param vid
* vhost device ID
* @param ops
* virtio external callbacks to register
* @param ctx
* additional context passed to the callbacks
* @return
* 0 on success, -1 on failure
*/
int
rte_vhost_extern_callback_register(int vid,
struct rte_vhost_user_extern_ops const * const ops, void *ctx);
/**
* Get vdpa device id for vhost device.
*
* @param vid
* vhost device id
* @return
* vDPA device pointer on success, NULL on failure
*/
struct rte_vdpa_device *
rte_vhost_get_vdpa_device(int vid);
/**
* Notify the guest that should get virtio configuration space from backend.
*
* @param vid
* vhost device ID
* @param need_reply
* wait for the master response the status of this operation
* @return
* 0 on success, < 0 on failure
*/
__rte_experimental
int
rte_vhost_slave_config_change(int vid, bool need_reply);
#ifdef __cplusplus
}
#endif
#endif /* _RTE_VHOST_H_ */