libvhost-user: make it a meson subproject

By making libvhost-user a subproject, check it builds
standalone (without the global QEMU cflags etc).

Note that the library still relies on QEMU include/qemu/atomic.h and
linux_headers/.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20201125100640.366523-6-marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

1 files changed, 0 insertions, 2883 deletions

diff --git a/contrib/libvhost-user/libvhost-user.c b/contrib/libvhost-user/libvhost-user.c
deleted file mode 100644
index fab7ca17ee..0000000000
--- a/contrib/libvhost-user/libvhost-user.c
+++ /dev/null
@@ -1,2883 +0,0 @@
-/*
- * Vhost User library
- *
- * Copyright IBM, Corp. 2007
- * Copyright (c) 2016 Red Hat, Inc.
- *
- * Authors:
- *  Anthony Liguori <aliguori@us.ibm.com>
- *  Marc-André Lureau <mlureau@redhat.com>
- *  Victor Kaplansky <victork@redhat.com>
- *
- * This work is licensed under the terms of the GNU GPL, version 2 or
- * later.  See the COPYING file in the top-level directory.
- */
-
-/* this code avoids GLib dependency */
-#include <stdlib.h>
-#include <stdio.h>
-#include <unistd.h>
-#include <stdarg.h>
-#include <errno.h>
-#include <string.h>
-#include <assert.h>
-#include <inttypes.h>
-#include <sys/types.h>
-#include <sys/socket.h>
-#include <sys/eventfd.h>
-#include <sys/mman.h>
-#include <endian.h>
-
-#if defined(__linux__)
-#include <sys/syscall.h>
-#include <fcntl.h>
-#include <sys/ioctl.h>
-#include <linux/vhost.h>
-
-#ifdef __NR_userfaultfd
-#include <linux/userfaultfd.h>
-#endif
-
-#endif
-
-#include "qemu/atomic.h"
-
-#include "libvhost-user.h"
-
-/* usually provided by GLib */
-#ifndef MIN
-#define MIN(x, y) ({                            \
-            typeof(x) _min1 = (x);              \
-            typeof(y) _min2 = (y);              \
-            (void) (&_min1 == &_min2);          \
-            _min1 < _min2 ? _min1 : _min2; })
-#endif
-
-/* Round number down to multiple */
-#define ALIGN_DOWN(n, m) ((n) / (m) * (m))
-
-/* Round number up to multiple */
-#define ALIGN_UP(n, m) ALIGN_DOWN((n) + (m) - 1, (m))
-
-#ifndef unlikely
-#define unlikely(x)   __builtin_expect(!!(x), 0)
-#endif
-
-/* Align each region to cache line size in inflight buffer */
-#define INFLIGHT_ALIGNMENT 64
-
-/* The version of inflight buffer */
-#define INFLIGHT_VERSION 1
-
-/* The version of the protocol we support */
-#define VHOST_USER_VERSION 1
-#define LIBVHOST_USER_DEBUG 0
-
-#define DPRINT(...)                             \
-    do {                                        \
-        if (LIBVHOST_USER_DEBUG) {              \
-            fprintf(stderr, __VA_ARGS__);        \
-        }                                       \
-    } while (0)
-
-static inline
-bool has_feature(uint64_t features, unsigned int fbit)
-{
-    assert(fbit < 64);
-    return !!(features & (1ULL << fbit));
-}
-
-static inline
-bool vu_has_feature(VuDev *dev,
-                    unsigned int fbit)
-{
-    return has_feature(dev->features, fbit);
-}
-
-static inline bool vu_has_protocol_feature(VuDev *dev, unsigned int fbit)
-{
-    return has_feature(dev->protocol_features, fbit);
-}
-
-static const char *
-vu_request_to_string(unsigned int req)
-{
-#define REQ(req) [req] = #req
-    static const char *vu_request_str[] = {
-        REQ(VHOST_USER_NONE),
-        REQ(VHOST_USER_GET_FEATURES),
-        REQ(VHOST_USER_SET_FEATURES),
-        REQ(VHOST_USER_SET_OWNER),
-        REQ(VHOST_USER_RESET_OWNER),
-        REQ(VHOST_USER_SET_MEM_TABLE),
-        REQ(VHOST_USER_SET_LOG_BASE),
-        REQ(VHOST_USER_SET_LOG_FD),
-        REQ(VHOST_USER_SET_VRING_NUM),
-        REQ(VHOST_USER_SET_VRING_ADDR),
-        REQ(VHOST_USER_SET_VRING_BASE),
-        REQ(VHOST_USER_GET_VRING_BASE),
-        REQ(VHOST_USER_SET_VRING_KICK),
-        REQ(VHOST_USER_SET_VRING_CALL),
-        REQ(VHOST_USER_SET_VRING_ERR),
-        REQ(VHOST_USER_GET_PROTOCOL_FEATURES),
-        REQ(VHOST_USER_SET_PROTOCOL_FEATURES),
-        REQ(VHOST_USER_GET_QUEUE_NUM),
-        REQ(VHOST_USER_SET_VRING_ENABLE),
-        REQ(VHOST_USER_SEND_RARP),
-        REQ(VHOST_USER_NET_SET_MTU),
-        REQ(VHOST_USER_SET_SLAVE_REQ_FD),
-        REQ(VHOST_USER_IOTLB_MSG),
-        REQ(VHOST_USER_SET_VRING_ENDIAN),
-        REQ(VHOST_USER_GET_CONFIG),
-        REQ(VHOST_USER_SET_CONFIG),
-        REQ(VHOST_USER_POSTCOPY_ADVISE),
-        REQ(VHOST_USER_POSTCOPY_LISTEN),
-        REQ(VHOST_USER_POSTCOPY_END),
-        REQ(VHOST_USER_GET_INFLIGHT_FD),
-        REQ(VHOST_USER_SET_INFLIGHT_FD),
-        REQ(VHOST_USER_GPU_SET_SOCKET),
-        REQ(VHOST_USER_VRING_KICK),
-        REQ(VHOST_USER_GET_MAX_MEM_SLOTS),
-        REQ(VHOST_USER_ADD_MEM_REG),
-        REQ(VHOST_USER_REM_MEM_REG),
-        REQ(VHOST_USER_MAX),
-    };
-#undef REQ
-
-    if (req < VHOST_USER_MAX) {
-        return vu_request_str[req];
-    } else {
-        return "unknown";
-    }
-}
-
-static void
-vu_panic(VuDev *dev, const char *msg, ...)
-{
-    char *buf = NULL;
-    va_list ap;
-
-    va_start(ap, msg);
-    if (vasprintf(&buf, msg, ap) < 0) {
-        buf = NULL;
-    }
-    va_end(ap);
-
-    dev->broken = true;
-    dev->panic(dev, buf);
-    free(buf);
-
-    /*
-     * FIXME:
-     * find a way to call virtio_error, or perhaps close the connection?
-     */
-}
-
-/* Translate guest physical address to our virtual address.  */
-void *
-vu_gpa_to_va(VuDev *dev, uint64_t *plen, uint64_t guest_addr)
-{
-    int i;
-
-    if (*plen == 0) {
-        return NULL;
-    }
-
-    /* Find matching memory region.  */
-    for (i = 0; i < dev->nregions; i++) {
-        VuDevRegion *r = &dev->regions[i];
-
-        if ((guest_addr >= r->gpa) && (guest_addr < (r->gpa + r->size))) {
-            if ((guest_addr + *plen) > (r->gpa + r->size)) {
-                *plen = r->gpa + r->size - guest_addr;
-            }
-            return (void *)(uintptr_t)
-                guest_addr - r->gpa + r->mmap_addr + r->mmap_offset;
-        }
-    }
-
-    return NULL;
-}
-
-/* Translate qemu virtual address to our virtual address.  */
-static void *
-qva_to_va(VuDev *dev, uint64_t qemu_addr)
-{
-    int i;
-
-    /* Find matching memory region.  */
-    for (i = 0; i < dev->nregions; i++) {
-        VuDevRegion *r = &dev->regions[i];
-
-        if ((qemu_addr >= r->qva) && (qemu_addr < (r->qva + r->size))) {
-            return (void *)(uintptr_t)
-                qemu_addr - r->qva + r->mmap_addr + r->mmap_offset;
-        }
-    }
-
-    return NULL;
-}
-
-static void
-vmsg_close_fds(VhostUserMsg *vmsg)
-{
-    int i;
-
-    for (i = 0; i < vmsg->fd_num; i++) {
-        close(vmsg->fds[i]);
-    }
-}
-
-/* Set reply payload.u64 and clear request flags and fd_num */
-static void vmsg_set_reply_u64(VhostUserMsg *vmsg, uint64_t val)
-{
-    vmsg->flags = 0; /* defaults will be set by vu_send_reply() */
-    vmsg->size = sizeof(vmsg->payload.u64);
-    vmsg->payload.u64 = val;
-    vmsg->fd_num = 0;
-}
-
-/* A test to see if we have userfault available */
-static bool
-have_userfault(void)
-{
-#if defined(__linux__) && defined(__NR_userfaultfd) &&\
-        defined(UFFD_FEATURE_MISSING_SHMEM) &&\
-        defined(UFFD_FEATURE_MISSING_HUGETLBFS)
-    /* Now test the kernel we're running on really has the features */
-    int ufd = syscall(__NR_userfaultfd, O_CLOEXEC | O_NONBLOCK);
-    struct uffdio_api api_struct;
-    if (ufd < 0) {
-        return false;
-    }
-
-    api_struct.api = UFFD_API;
-    api_struct.features = UFFD_FEATURE_MISSING_SHMEM |
-                          UFFD_FEATURE_MISSING_HUGETLBFS;
-    if (ioctl(ufd, UFFDIO_API, &api_struct)) {
-        close(ufd);
-        return false;
-    }
-    close(ufd);
-    return true;
-
-#else
-    return false;
-#endif
-}
-
-static bool
-vu_message_read_default(VuDev *dev, int conn_fd, VhostUserMsg *vmsg)
-{
-    char control[CMSG_SPACE(VHOST_MEMORY_BASELINE_NREGIONS * sizeof(int))] = {};
-    struct iovec iov = {
-        .iov_base = (char *)vmsg,
-        .iov_len = VHOST_USER_HDR_SIZE,
-    };
-    struct msghdr msg = {
-        .msg_iov = &iov,
-        .msg_iovlen = 1,
-        .msg_control = control,
-        .msg_controllen = sizeof(control),
-    };
-    size_t fd_size;
-    struct cmsghdr *cmsg;
-    int rc;
-
-    do {
-        rc = recvmsg(conn_fd, &msg, 0);
-    } while (rc < 0 && (errno == EINTR || errno == EAGAIN));
-
-    if (rc < 0) {
-        vu_panic(dev, "Error while recvmsg: %s", strerror(errno));
-        return false;
-    }
-
-    vmsg->fd_num = 0;
-    for (cmsg = CMSG_FIRSTHDR(&msg);
-         cmsg != NULL;
-         cmsg = CMSG_NXTHDR(&msg, cmsg))
-    {
-        if (cmsg->cmsg_level == SOL_SOCKET && cmsg->cmsg_type == SCM_RIGHTS) {
-            fd_size = cmsg->cmsg_len - CMSG_LEN(0);
-            vmsg->fd_num = fd_size / sizeof(int);
-            memcpy(vmsg->fds, CMSG_DATA(cmsg), fd_size);
-            break;
-        }
-    }
-
-    if (vmsg->size > sizeof(vmsg->payload)) {
-        vu_panic(dev,
-                 "Error: too big message request: %d, size: vmsg->size: %u, "
-                 "while sizeof(vmsg->payload) = %zu\n",
-                 vmsg->request, vmsg->size, sizeof(vmsg->payload));
-        goto fail;
-    }
-
-    if (vmsg->size) {
-        do {
-            rc = read(conn_fd, &vmsg->payload, vmsg->size);
-        } while (rc < 0 && (errno == EINTR || errno == EAGAIN));
-
-        if (rc <= 0) {
-            vu_panic(dev, "Error while reading: %s", strerror(errno));
-            goto fail;
-        }
-
-        assert(rc == vmsg->size);
-    }
-
-    return true;
-
-fail:
-    vmsg_close_fds(vmsg);
-
-    return false;
-}
-
-static bool
-vu_message_write(VuDev *dev, int conn_fd, VhostUserMsg *vmsg)
-{
-    int rc;
-    uint8_t *p = (uint8_t *)vmsg;
-    char control[CMSG_SPACE(VHOST_MEMORY_BASELINE_NREGIONS * sizeof(int))] = {};
-    struct iovec iov = {
-        .iov_base = (char *)vmsg,
-        .iov_len = VHOST_USER_HDR_SIZE,
-    };
-    struct msghdr msg = {
-        .msg_iov = &iov,
-        .msg_iovlen = 1,
-        .msg_control = control,
-    };
-    struct cmsghdr *cmsg;
-
-    memset(control, 0, sizeof(control));
-    assert(vmsg->fd_num <= VHOST_MEMORY_BASELINE_NREGIONS);
-    if (vmsg->fd_num > 0) {
-        size_t fdsize = vmsg->fd_num * sizeof(int);
-        msg.msg_controllen = CMSG_SPACE(fdsize);
-        cmsg = CMSG_FIRSTHDR(&msg);
-        cmsg->cmsg_len = CMSG_LEN(fdsize);
-        cmsg->cmsg_level = SOL_SOCKET;
-        cmsg->cmsg_type = SCM_RIGHTS;
-        memcpy(CMSG_DATA(cmsg), vmsg->fds, fdsize);
-    } else {
-        msg.msg_controllen = 0;
-    }
-
-    do {
-        rc = sendmsg(conn_fd, &msg, 0);
-    } while (rc < 0 && (errno == EINTR || errno == EAGAIN));
-
-    if (vmsg->size) {
-        do {
-            if (vmsg->data) {
-                rc = write(conn_fd, vmsg->data, vmsg->size);
-            } else {
-                rc = write(conn_fd, p + VHOST_USER_HDR_SIZE, vmsg->size);
-            }
-        } while (rc < 0 && (errno == EINTR || errno == EAGAIN));
-    }
-
-    if (rc <= 0) {
-        vu_panic(dev, "Error while writing: %s", strerror(errno));
-        return false;
-    }
-
-    return true;
-}
-
-static bool
-vu_send_reply(VuDev *dev, int conn_fd, VhostUserMsg *vmsg)
-{
-    /* Set the version in the flags when sending the reply */
-    vmsg->flags &= ~VHOST_USER_VERSION_MASK;
-    vmsg->flags |= VHOST_USER_VERSION;
-    vmsg->flags |= VHOST_USER_REPLY_MASK;
-
-    return vu_message_write(dev, conn_fd, vmsg);
-}
-
-/*
- * Processes a reply on the slave channel.
- * Entered with slave_mutex held and releases it before exit.
- * Returns true on success.
- */
-static bool
-vu_process_message_reply(VuDev *dev, const VhostUserMsg *vmsg)
-{
-    VhostUserMsg msg_reply;
-    bool result = false;
-
-    if ((vmsg->flags & VHOST_USER_NEED_REPLY_MASK) == 0) {
-        result = true;
-        goto out;
-    }
-
-    if (!vu_message_read_default(dev, dev->slave_fd, &msg_reply)) {
-        goto out;
-    }
-
-    if (msg_reply.request != vmsg->request) {
-        DPRINT("Received unexpected msg type. Expected %d received %d",
-               vmsg->request, msg_reply.request);
-        goto out;
-    }
-
-    result = msg_reply.payload.u64 == 0;
-
-out:
-    pthread_mutex_unlock(&dev->slave_mutex);
-    return result;
-}
-
-/* Kick the log_call_fd if required. */
-static void
-vu_log_kick(VuDev *dev)
-{
-    if (dev->log_call_fd != -1) {
-        DPRINT("Kicking the QEMU's log...\n");
-        if (eventfd_write(dev->log_call_fd, 1) < 0) {
-            vu_panic(dev, "Error writing eventfd: %s", strerror(errno));
-        }
-    }
-}
-
-static void
-vu_log_page(uint8_t *log_table, uint64_t page)
-{
-    DPRINT("Logged dirty guest page: %"PRId64"\n", page);
-    qatomic_or(&log_table[page / 8], 1 << (page % 8));
-}
-
-static void
-vu_log_write(VuDev *dev, uint64_t address, uint64_t length)
-{
-    uint64_t page;
-
-    if (!(dev->features & (1ULL << VHOST_F_LOG_ALL)) ||
-        !dev->log_table || !length) {
-        return;
-    }
-
-    assert(dev->log_size > ((address + length - 1) / VHOST_LOG_PAGE / 8));
-
-    page = address / VHOST_LOG_PAGE;
-    while (page * VHOST_LOG_PAGE < address + length) {
-        vu_log_page(dev->log_table, page);
-        page += 1;
-    }
-
-    vu_log_kick(dev);
-}
-
-static void
-vu_kick_cb(VuDev *dev, int condition, void *data)
-{
-    int index = (intptr_t)data;
-    VuVirtq *vq = &dev->vq[index];
-    int sock = vq->kick_fd;
-    eventfd_t kick_data;
-    ssize_t rc;
-
-    rc = eventfd_read(sock, &kick_data);
-    if (rc == -1) {
-        vu_panic(dev, "kick eventfd_read(): %s", strerror(errno));
-        dev->remove_watch(dev, dev->vq[index].kick_fd);
-    } else {
-        DPRINT("Got kick_data: %016"PRIx64" handler:%p idx:%d\n",
-               kick_data, vq->handler, index);
-        if (vq->handler) {
-            vq->handler(dev, index);
-        }
-    }
-}
-
-static bool
-vu_get_features_exec(VuDev *dev, VhostUserMsg *vmsg)
-{
-    vmsg->payload.u64 =
-        /*
-         * The following VIRTIO feature bits are supported by our virtqueue
-         * implementation:
-         */
-        1ULL << VIRTIO_F_NOTIFY_ON_EMPTY |
-        1ULL << VIRTIO_RING_F_INDIRECT_DESC |
-        1ULL << VIRTIO_RING_F_EVENT_IDX |
-        1ULL << VIRTIO_F_VERSION_1 |
-
-        /* vhost-user feature bits */
-        1ULL << VHOST_F_LOG_ALL |
-        1ULL << VHOST_USER_F_PROTOCOL_FEATURES;
-
-    if (dev->iface->get_features) {
-        vmsg->payload.u64 |= dev->iface->get_features(dev);
-    }
-
-    vmsg->size = sizeof(vmsg->payload.u64);
-    vmsg->fd_num = 0;
-
-    DPRINT("Sending back to guest u64: 0x%016"PRIx64"\n", vmsg->payload.u64);
-
-    return true;
-}
-
-static void
-vu_set_enable_all_rings(VuDev *dev, bool enabled)
-{
-    uint16_t i;
-
-    for (i = 0; i < dev->max_queues; i++) {
-        dev->vq[i].enable = enabled;
-    }
-}
-
-static bool
-vu_set_features_exec(VuDev *dev, VhostUserMsg *vmsg)
-{
-    DPRINT("u64: 0x%016"PRIx64"\n", vmsg->payload.u64);
-
-    dev->features = vmsg->payload.u64;
-    if (!vu_has_feature(dev, VIRTIO_F_VERSION_1)) {
-        /*
-         * We only support devices conforming to VIRTIO 1.0 or
-         * later
-         */
-        vu_panic(dev, "virtio legacy devices aren't supported by libvhost-user");
-        return false;
-    }
-
-    if (!(dev->features & VHOST_USER_F_PROTOCOL_FEATURES)) {
-        vu_set_enable_all_rings(dev, true);
-    }
-
-    if (dev->iface->set_features) {
-        dev->iface->set_features(dev, dev->features);
-    }
-
-    return false;
-}
-
-static bool
-vu_set_owner_exec(VuDev *dev, VhostUserMsg *vmsg)
-{
-    return false;
-}
-
-static void
-vu_close_log(VuDev *dev)
-{
-    if (dev->log_table) {
-        if (munmap(dev->log_table, dev->log_size) != 0) {
-            perror("close log munmap() error");
-        }
-
-        dev->log_table = NULL;
-    }
-    if (dev->log_call_fd != -1) {
-        close(dev->log_call_fd);
-        dev->log_call_fd = -1;
-    }
-}
-
-static bool
-vu_reset_device_exec(VuDev *dev, VhostUserMsg *vmsg)
-{
-    vu_set_enable_all_rings(dev, false);
-
-    return false;
-}
-
-static bool
-map_ring(VuDev *dev, VuVirtq *vq)
-{
-    vq->vring.desc = qva_to_va(dev, vq->vra.desc_user_addr);
-    vq->vring.used = qva_to_va(dev, vq->vra.used_user_addr);
-    vq->vring.avail = qva_to_va(dev, vq->vra.avail_user_addr);
-
-    DPRINT("Setting virtq addresses:\n");
-    DPRINT("    vring_desc  at %p\n", vq->vring.desc);
-    DPRINT("    vring_used  at %p\n", vq->vring.used);
-    DPRINT("    vring_avail at %p\n", vq->vring.avail);
-
-    return !(vq->vring.desc && vq->vring.used && vq->vring.avail);
-}
-
-static bool
-generate_faults(VuDev *dev) {
-    int i;
-    for (i = 0; i < dev->nregions; i++) {
-        VuDevRegion *dev_region = &dev->regions[i];
-        int ret;
-#ifdef UFFDIO_REGISTER
-        /*
-         * We should already have an open ufd. Mark each memory
-         * range as ufd.
-         * Discard any mapping we have here; note I can't use MADV_REMOVE
-         * or fallocate to make the hole since I don't want to lose
-         * data that's already arrived in the shared process.
-         * TODO: How to do hugepage
-         */
-        ret = madvise((void *)(uintptr_t)dev_region->mmap_addr,
-                      dev_region->size + dev_region->mmap_offset,
-                      MADV_DONTNEED);
-        if (ret) {
-            fprintf(stderr,
-                    "%s: Failed to madvise(DONTNEED) region %d: %s\n",
-                    __func__, i, strerror(errno));
-        }
-        /*
-         * Turn off transparent hugepages so we dont get lose wakeups
-         * in neighbouring pages.
-         * TODO: Turn this backon later.
-         */
-        ret = madvise((void *)(uintptr_t)dev_region->mmap_addr,
-                      dev_region->size + dev_region->mmap_offset,
-                      MADV_NOHUGEPAGE);
-        if (ret) {
-            /*
-             * Note: This can happen legally on kernels that are configured
-             * without madvise'able hugepages
-             */
-            fprintf(stderr,
-                    "%s: Failed to madvise(NOHUGEPAGE) region %d: %s\n",
-                    __func__, i, strerror(errno));
-        }
-        struct uffdio_register reg_struct;
-        reg_struct.range.start = (uintptr_t)dev_region->mmap_addr;
-        reg_struct.range.len = dev_region->size + dev_region->mmap_offset;
-        reg_struct.mode = UFFDIO_REGISTER_MODE_MISSING;
-
-        if (ioctl(dev->postcopy_ufd, UFFDIO_REGISTER, &reg_struct)) {
-            vu_panic(dev, "%s: Failed to userfault region %d "
-                          "@%p + size:%zx offset: %zx: (ufd=%d)%s\n",
-                     __func__, i,
-                     dev_region->mmap_addr,
-                     dev_region->size, dev_region->mmap_offset,
-                     dev->postcopy_ufd, strerror(errno));
-            return false;
-        }
-        if (!(reg_struct.ioctls & ((__u64)1 << _UFFDIO_COPY))) {
-            vu_panic(dev, "%s Region (%d) doesn't support COPY",
-                     __func__, i);
-            return false;
-        }
-        DPRINT("%s: region %d: Registered userfault for %"
-               PRIx64 " + %" PRIx64 "\n", __func__, i,
-               (uint64_t)reg_struct.range.start,
-               (uint64_t)reg_struct.range.len);
-        /* Now it's registered we can let the client at it */
-        if (mprotect((void *)(uintptr_t)dev_region->mmap_addr,
-                     dev_region->size + dev_region->mmap_offset,
-                     PROT_READ | PROT_WRITE)) {
-            vu_panic(dev, "failed to mprotect region %d for postcopy (%s)",
-                     i, strerror(errno));
-            return false;
-        }
-        /* TODO: Stash 'zero' support flags somewhere */
-#endif
-    }
-
-    return true;
-}
-
-static bool
-vu_add_mem_reg(VuDev *dev, VhostUserMsg *vmsg) {
-    int i;
-    bool track_ramblocks = dev->postcopy_listening;
-    VhostUserMemoryRegion m = vmsg->payload.memreg.region, *msg_region = &m;
-    VuDevRegion *dev_region = &dev->regions[dev->nregions];
-    void *mmap_addr;
-
-    /*
-     * If we are in postcopy mode and we receive a u64 payload with a 0 value
-     * we know all the postcopy client bases have been received, and we
-     * should start generating faults.
-     */
-    if (track_ramblocks &&
-        vmsg->size == sizeof(vmsg->payload.u64) &&
-        vmsg->payload.u64 == 0) {
-        (void)generate_faults(dev);
-        return false;
-    }
-
-    DPRINT("Adding region: %u\n", dev->nregions);
-    DPRINT("    guest_phys_addr: 0x%016"PRIx64"\n",
-           msg_region->guest_phys_addr);
-    DPRINT("    memory_size:     0x%016"PRIx64"\n",
-           msg_region->memory_size);
-    DPRINT("    userspace_addr   0x%016"PRIx64"\n",
-           msg_region->userspace_addr);
-    DPRINT("    mmap_offset      0x%016"PRIx64"\n",
-           msg_region->mmap_offset);
-
-    dev_region->gpa = msg_region->guest_phys_addr;
-    dev_region->size = msg_region->memory_size;
-    dev_region->qva = msg_region->userspace_addr;
-    dev_region->mmap_offset = msg_region->mmap_offset;
-
-    /*
-     * We don't use offset argument of mmap() since the
-     * mapped address has to be page aligned, and we use huge
-     * pages.
-     */
-    if (track_ramblocks) {
-        /*
-         * In postcopy we're using PROT_NONE here to catch anyone
-         * accessing it before we userfault.
-         */
-        mmap_addr = mmap(0, dev_region->size + dev_region->mmap_offset,
-                         PROT_NONE, MAP_SHARED,
-                         vmsg->fds[0], 0);
-    } else {
-        mmap_addr = mmap(0, dev_region->size + dev_region->mmap_offset,
-                         PROT_READ | PROT_WRITE, MAP_SHARED, vmsg->fds[0],
-                         0);
-    }
-
-    if (mmap_addr == MAP_FAILED) {
-        vu_panic(dev, "region mmap error: %s", strerror(errno));
-    } else {
-        dev_region->mmap_addr = (uint64_t)(uintptr_t)mmap_addr;
-        DPRINT("    mmap_addr:       0x%016"PRIx64"\n",
-               dev_region->mmap_addr);
-    }
-
-    close(vmsg->fds[0]);
-
-    if (track_ramblocks) {
-        /*
-         * Return the address to QEMU so that it can translate the ufd
-         * fault addresses back.
-         */
-        msg_region->userspace_addr = (uintptr_t)(mmap_addr +
-                                                 dev_region->mmap_offset);
-
-        /* Send the message back to qemu with the addresses filled in. */
-        vmsg->fd_num = 0;
-        if (!vu_send_reply(dev, dev->sock, vmsg)) {
-            vu_panic(dev, "failed to respond to add-mem-region for postcopy");
-            return false;
-        }
-
-        DPRINT("Successfully added new region in postcopy\n");
-        dev->nregions++;
-        return false;
-
-    } else {
-        for (i = 0; i < dev->max_queues; i++) {
-            if (dev->vq[i].vring.desc) {
-                if (map_ring(dev, &dev->vq[i])) {
-                    vu_panic(dev, "remapping queue %d for new memory region",
-                             i);
-                }
-            }
-        }
-
-        DPRINT("Successfully added new region\n");
-        dev->nregions++;
-        vmsg_set_reply_u64(vmsg, 0);
-        return true;
-    }
-}
-
-static inline bool reg_equal(VuDevRegion *vudev_reg,
-                             VhostUserMemoryRegion *msg_reg)
-{
-    if (vudev_reg->gpa == msg_reg->guest_phys_addr &&
-        vudev_reg->qva == msg_reg->userspace_addr &&
-        vudev_reg->size == msg_reg->memory_size) {
-        return true;
-    }
-
-    return false;
-}
-
-static bool
-vu_rem_mem_reg(VuDev *dev, VhostUserMsg *vmsg) {
-    int i, j;
-    bool found = false;
-    VuDevRegion shadow_regions[VHOST_USER_MAX_RAM_SLOTS] = {};
-    VhostUserMemoryRegion m = vmsg->payload.memreg.region, *msg_region = &m;
-
-    DPRINT("Removing region:\n");
-    DPRINT("    guest_phys_addr: 0x%016"PRIx64"\n",
-           msg_region->guest_phys_addr);
-    DPRINT("    memory_size:     0x%016"PRIx64"\n",
-           msg_region->memory_size);
-    DPRINT("    userspace_addr   0x%016"PRIx64"\n",
-           msg_region->userspace_addr);
-    DPRINT("    mmap_offset      0x%016"PRIx64"\n",
-           msg_region->mmap_offset);
-
-    for (i = 0, j = 0; i < dev->nregions; i++) {
-        if (!reg_equal(&dev->regions[i], msg_region)) {
-            shadow_regions[j].gpa = dev->regions[i].gpa;
-            shadow_regions[j].size = dev->regions[i].size;
-            shadow_regions[j].qva = dev->regions[i].qva;
-            shadow_regions[j].mmap_offset = dev->regions[i].mmap_offset;
-            j++;
-        } else {
-            found = true;
-            VuDevRegion *r = &dev->regions[i];
-            void *m = (void *) (uintptr_t) r->mmap_addr;
-
-            if (m) {
-                munmap(m, r->size + r->mmap_offset);
-            }
-        }
-    }
-
-    if (found) {
-        memcpy(dev->regions, shadow_regions,
-               sizeof(VuDevRegion) * VHOST_USER_MAX_RAM_SLOTS);
-        DPRINT("Successfully removed a region\n");
-        dev->nregions--;
-        vmsg_set_reply_u64(vmsg, 0);
-    } else {
-        vu_panic(dev, "Specified region not found\n");
-    }
-
-    return true;
-}
-
-static bool
-vu_set_mem_table_exec_postcopy(VuDev *dev, VhostUserMsg *vmsg)
-{
-    int i;
-    VhostUserMemory m = vmsg->payload.memory, *memory = &m;
-    dev->nregions = memory->nregions;
-
-    DPRINT("Nregions: %u\n", memory->nregions);
-    for (i = 0; i < dev->nregions; i++) {
-        void *mmap_addr;
-        VhostUserMemoryRegion *msg_region = &memory->regions[i];
-        VuDevRegion *dev_region = &dev->regions[i];
-
-        DPRINT("Region %d\n", i);
-        DPRINT("    guest_phys_addr: 0x%016"PRIx64"\n",
-               msg_region->guest_phys_addr);
-        DPRINT("    memory_size:     0x%016"PRIx64"\n",
-               msg_region->memory_size);
-        DPRINT("    userspace_addr   0x%016"PRIx64"\n",
-               msg_region->userspace_addr);
-        DPRINT("    mmap_offset      0x%016"PRIx64"\n",
-               msg_region->mmap_offset);
-
-        dev_region->gpa = msg_region->guest_phys_addr;
-        dev_region->size = msg_region->memory_size;
-        dev_region->qva = msg_region->userspace_addr;
-        dev_region->mmap_offset = msg_region->mmap_offset;
-
-        /* We don't use offset argument of mmap() since the
-         * mapped address has to be page aligned, and we use huge
-         * pages.
-         * In postcopy we're using PROT_NONE here to catch anyone
-         * accessing it before we userfault
-         */
-        mmap_addr = mmap(0, dev_region->size + dev_region->mmap_offset,
-                         PROT_NONE, MAP_SHARED,
-                         vmsg->fds[i], 0);
-
-        if (mmap_addr == MAP_FAILED) {
-            vu_panic(dev, "region mmap error: %s", strerror(errno));
-        } else {
-            dev_region->mmap_addr = (uint64_t)(uintptr_t)mmap_addr;
-            DPRINT("    mmap_addr:       0x%016"PRIx64"\n",
-                   dev_region->mmap_addr);
-        }
-
-        /* Return the address to QEMU so that it can translate the ufd
-         * fault addresses back.
-         */
-        msg_region->userspace_addr = (uintptr_t)(mmap_addr +
-                                                 dev_region->mmap_offset);
-        close(vmsg->fds[i]);
-    }
-
-    /* Send the message back to qemu with the addresses filled in */
-    vmsg->fd_num = 0;
-    if (!vu_send_reply(dev, dev->sock, vmsg)) {
-        vu_panic(dev, "failed to respond to set-mem-table for postcopy");
-        return false;
-    }
-
-    /* Wait for QEMU to confirm that it's registered the handler for the
-     * faults.
-     */
-    if (!dev->read_msg(dev, dev->sock, vmsg) ||
-        vmsg->size != sizeof(vmsg->payload.u64) ||
-        vmsg->payload.u64 != 0) {
-        vu_panic(dev, "failed to receive valid ack for postcopy set-mem-table");
-        return false;
-    }
-
-    /* OK, now we can go and register the memory and generate faults */
-    (void)generate_faults(dev);
-
-    return false;
-}
-
-static bool
-vu_set_mem_table_exec(VuDev *dev, VhostUserMsg *vmsg)
-{
-    int i;
-    VhostUserMemory m = vmsg->payload.memory, *memory = &m;
-
-    for (i = 0; i < dev->nregions; i++) {
-        VuDevRegion *r = &dev->regions[i];
-        void *m = (void *) (uintptr_t) r->mmap_addr;
-
-        if (m) {
-            munmap(m, r->size + r->mmap_offset);
-        }
-    }
-    dev->nregions = memory->nregions;
-
-    if (dev->postcopy_listening) {
-        return vu_set_mem_table_exec_postcopy(dev, vmsg);
-    }
-
-    DPRINT("Nregions: %u\n", memory->nregions);
-    for (i = 0; i < dev->nregions; i++) {
-        void *mmap_addr;
-        VhostUserMemoryRegion *msg_region = &memory->regions[i];
-        VuDevRegion *dev_region = &dev->regions[i];
-
-        DPRINT("Region %d\n", i);
-        DPRINT("    guest_phys_addr: 0x%016"PRIx64"\n",
-               msg_region->guest_phys_addr);
-        DPRINT("    memory_size:     0x%016"PRIx64"\n",
-               msg_region->memory_size);
-        DPRINT("    userspace_addr   0x%016"PRIx64"\n",
-               msg_region->userspace_addr);
-        DPRINT("    mmap_offset      0x%016"PRIx64"\n",
-               msg_region->mmap_offset);
-
-        dev_region->gpa = msg_region->guest_phys_addr;
-        dev_region->size = msg_region->memory_size;
-        dev_region->qva = msg_region->userspace_addr;
-        dev_region->mmap_offset = msg_region->mmap_offset;
-
-        /* We don't use offset argument of mmap() since the
-         * mapped address has to be page aligned, and we use huge
-         * pages.  */
-        mmap_addr = mmap(0, dev_region->size + dev_region->mmap_offset,
-                         PROT_READ | PROT_WRITE, MAP_SHARED,
-                         vmsg->fds[i], 0);
-
-        if (mmap_addr == MAP_FAILED) {
-            vu_panic(dev, "region mmap error: %s", strerror(errno));
-        } else {
-            dev_region->mmap_addr = (uint64_t)(uintptr_t)mmap_addr;
-            DPRINT("    mmap_addr:       0x%016"PRIx64"\n",
-                   dev_region->mmap_addr);
-        }
-
-        close(vmsg->fds[i]);
-    }
-
-    for (i = 0; i < dev->max_queues; i++) {
-        if (dev->vq[i].vring.desc) {
-            if (map_ring(dev, &dev->vq[i])) {
-                vu_panic(dev, "remapping queue %d during setmemtable", i);
-            }
-        }
-    }
-
-    return false;
-}
-
-static bool
-vu_set_log_base_exec(VuDev *dev, VhostUserMsg *vmsg)
-{
-    int fd;
-    uint64_t log_mmap_size, log_mmap_offset;
-    void *rc;
-
-    if (vmsg->fd_num != 1 ||
-        vmsg->size != sizeof(vmsg->payload.log)) {
-        vu_panic(dev, "Invalid log_base message");
-        return true;
-    }
-
-    fd = vmsg->fds[0];
-    log_mmap_offset = vmsg->payload.log.mmap_offset;
-    log_mmap_size = vmsg->payload.log.mmap_size;
-    DPRINT("Log mmap_offset: %"PRId64"\n", log_mmap_offset);
-    DPRINT("Log mmap_size:   %"PRId64"\n", log_mmap_size);
-
-    rc = mmap(0, log_mmap_size, PROT_READ | PROT_WRITE, MAP_SHARED, fd,
-              log_mmap_offset);
-    close(fd);
-    if (rc == MAP_FAILED) {
-        perror("log mmap error");
-    }
-
-    if (dev->log_table) {
-        munmap(dev->log_table, dev->log_size);
-    }
-    dev->log_table = rc;
-    dev->log_size = log_mmap_size;
-
-    vmsg->size = sizeof(vmsg->payload.u64);
-    vmsg->fd_num = 0;
-
-    return true;
-}
-
-static bool
-vu_set_log_fd_exec(VuDev *dev, VhostUserMsg *vmsg)
-{
-    if (vmsg->fd_num != 1) {
-        vu_panic(dev, "Invalid log_fd message");
-        return false;
-    }
-
-    if (dev->log_call_fd != -1) {
-        close(dev->log_call_fd);
-    }
-    dev->log_call_fd = vmsg->fds[0];
-    DPRINT("Got log_call_fd: %d\n", vmsg->fds[0]);
-
-    return false;
-}
-
-static bool
-vu_set_vring_num_exec(VuDev *dev, VhostUserMsg *vmsg)
-{
-    unsigned int index = vmsg->payload.state.index;
-    unsigned int num = vmsg->payload.state.num;
-
-    DPRINT("State.index: %u\n", index);
-    DPRINT("State.num:   %u\n", num);
-    dev->vq[index].vring.num = num;
-
-    return false;
-}
-
-static bool
-vu_set_vring_addr_exec(VuDev *dev, VhostUserMsg *vmsg)
-{
-    struct vhost_vring_addr addr = vmsg->payload.addr, *vra = &addr;
-    unsigned int index = vra->index;
-    VuVirtq *vq = &dev->vq[index];
-
-    DPRINT("vhost_vring_addr:\n");
-    DPRINT("    index:  %d\n", vra->index);
-    DPRINT("    flags:  %d\n", vra->flags);
-    DPRINT("    desc_user_addr:   0x%016" PRIx64 "\n", vra->desc_user_addr);
-    DPRINT("    used_user_addr:   0x%016" PRIx64 "\n", vra->used_user_addr);
-    DPRINT("    avail_user_addr:  0x%016" PRIx64 "\n", vra->avail_user_addr);
-    DPRINT("    log_guest_addr:   0x%016" PRIx64 "\n", vra->log_guest_addr);
-
-    vq->vra = *vra;
-    vq->vring.flags = vra->flags;
-    vq->vring.log_guest_addr = vra->log_guest_addr;
-
-
-    if (map_ring(dev, vq)) {
-        vu_panic(dev, "Invalid vring_addr message");
-        return false;
-    }
-
-    vq->used_idx = le16toh(vq->vring.used->idx);
-
-    if (vq->last_avail_idx != vq->used_idx) {
-        bool resume = dev->iface->queue_is_processed_in_order &&
-            dev->iface->queue_is_processed_in_order(dev, index);
-
-        DPRINT("Last avail index != used index: %u != %u%s\n",
-               vq->last_avail_idx, vq->used_idx,
-               resume ? ", resuming" : "");
-
-        if (resume) {
-            vq->shadow_avail_idx = vq->last_avail_idx = vq->used_idx;
-        }
-    }
-
-    return false;
-}
-
-static bool
-vu_set_vring_base_exec(VuDev *dev, VhostUserMsg *vmsg)
-{
-    unsigned int index = vmsg->payload.state.index;
-    unsigned int num = vmsg->payload.state.num;
-
-    DPRINT("State.index: %u\n", index);
-    DPRINT("State.num:   %u\n", num);
-    dev->vq[index].shadow_avail_idx = dev->vq[index].last_avail_idx = num;
-
-    return false;
-}
-
-static bool
-vu_get_vring_base_exec(VuDev *dev, VhostUserMsg *vmsg)
-{
-    unsigned int index = vmsg->payload.state.index;
-
-    DPRINT("State.index: %u\n", index);
-    vmsg->payload.state.num = dev->vq[index].last_avail_idx;
-    vmsg->size = sizeof(vmsg->payload.state);
-
-    dev->vq[index].started = false;
-    if (dev->iface->queue_set_started) {
-        dev->iface->queue_set_started(dev, index, false);
-    }
-
-    if (dev->vq[index].call_fd != -1) {
-        close(dev->vq[index].call_fd);
-        dev->vq[index].call_fd = -1;
-    }
-    if (dev->vq[index].kick_fd != -1) {
-        dev->remove_watch(dev, dev->vq[index].kick_fd);
-        close(dev->vq[index].kick_fd);
-        dev->vq[index].kick_fd = -1;
-    }
-
-    return true;
-}
-
-static bool
-vu_check_queue_msg_file(VuDev *dev, VhostUserMsg *vmsg)
-{
-    int index = vmsg->payload.u64 & VHOST_USER_VRING_IDX_MASK;
-    bool nofd = vmsg->payload.u64 & VHOST_USER_VRING_NOFD_MASK;
-
-    if (index >= dev->max_queues) {
-        vmsg_close_fds(vmsg);
-        vu_panic(dev, "Invalid queue index: %u", index);
-        return false;
-    }
-
-    if (nofd) {
-        vmsg_close_fds(vmsg);
-        return true;
-    }
-
-    if (vmsg->fd_num != 1) {
-        vmsg_close_fds(vmsg);
-        vu_panic(dev, "Invalid fds in request: %d", vmsg->request);
-        return false;
-    }
-
-    return true;
-}
-
-static int
-inflight_desc_compare(const void *a, const void *b)
-{
-    VuVirtqInflightDesc *desc0 = (VuVirtqInflightDesc *)a,
-                        *desc1 = (VuVirtqInflightDesc *)b;
-
-    if (desc1->counter > desc0->counter &&
-        (desc1->counter - desc0->counter) < VIRTQUEUE_MAX_SIZE * 2) {
-        return 1;
-    }
-
-    return -1;
-}
-
-static int
-vu_check_queue_inflights(VuDev *dev, VuVirtq *vq)
-{
-    int i = 0;
-
-    if (!vu_has_protocol_feature(dev, VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD)) {
-        return 0;
-    }
-
-    if (unlikely(!vq->inflight)) {
-        return -1;
-    }
-
-    if (unlikely(!vq->inflight->version)) {
-        /* initialize the buffer */
-        vq->inflight->version = INFLIGHT_VERSION;
-        return 0;
-    }
-
-    vq->used_idx = le16toh(vq->vring.used->idx);
-    vq->resubmit_num = 0;
-    vq->resubmit_list = NULL;
-    vq->counter = 0;
-
-    if (unlikely(vq->inflight->used_idx != vq->used_idx)) {
-        vq->inflight->desc[vq->inflight->last_batch_head].inflight = 0;
-
-        barrier();
-
-        vq->inflight->used_idx = vq->used_idx;
-    }
-
-    for (i = 0; i < vq->inflight->desc_num; i++) {
-        if (vq->inflight->desc[i].inflight == 1) {
-            vq->inuse++;
-        }
-    }
-
-    vq->shadow_avail_idx = vq->last_avail_idx = vq->inuse + vq->used_idx;
-
-    if (vq->inuse) {
-        vq->resubmit_list = calloc(vq->inuse, sizeof(VuVirtqInflightDesc));
-        if (!vq->resubmit_list) {
-            return -1;
-        }
-
-        for (i = 0; i < vq->inflight->desc_num; i++) {
-            if (vq->inflight->desc[i].inflight) {
-                vq->resubmit_list[vq->resubmit_num].index = i;
-                vq->resubmit_list[vq->resubmit_num].counter =
-                                        vq->inflight->desc[i].counter;
-                vq->resubmit_num++;
-            }
-        }
-
-        if (vq->resubmit_num > 1) {
-            qsort(vq->resubmit_list, vq->resubmit_num,
-                  sizeof(VuVirtqInflightDesc), inflight_desc_compare);
-        }
-        vq->counter = vq->resubmit_list[0].counter + 1;
-    }
-
-    /* in case of I/O hang after reconnecting */
-    if (eventfd_write(vq->kick_fd, 1)) {
-        return -1;
-    }
-
-    return 0;
-}
-
-static bool
-vu_set_vring_kick_exec(VuDev *dev, VhostUserMsg *vmsg)
-{
-    int index = vmsg->payload.u64 & VHOST_USER_VRING_IDX_MASK;
-    bool nofd = vmsg->payload.u64 & VHOST_USER_VRING_NOFD_MASK;
-
-    DPRINT("u64: 0x%016"PRIx64"\n", vmsg->payload.u64);
-
-    if (!vu_check_queue_msg_file(dev, vmsg)) {
-        return false;
-    }
-
-    if (dev->vq[index].kick_fd != -1) {
-        dev->remove_watch(dev, dev->vq[index].kick_fd);
-        close(dev->vq[index].kick_fd);
-        dev->vq[index].kick_fd = -1;
-    }
-
-    dev->vq[index].kick_fd = nofd ? -1 : vmsg->fds[0];
-    DPRINT("Got kick_fd: %d for vq: %d\n", dev->vq[index].kick_fd, index);
-
-    dev->vq[index].started = true;
-    if (dev->iface->queue_set_started) {
-        dev->iface->queue_set_started(dev, index, true);
-    }
-
-    if (dev->vq[index].kick_fd != -1 && dev->vq[index].handler) {
-        dev->set_watch(dev, dev->vq[index].kick_fd, VU_WATCH_IN,
-                       vu_kick_cb, (void *)(long)index);
-
-        DPRINT("Waiting for kicks on fd: %d for vq: %d\n",
-               dev->vq[index].kick_fd, index);
-    }
-
-    if (vu_check_queue_inflights(dev, &dev->vq[index])) {
-        vu_panic(dev, "Failed to check inflights for vq: %d\n", index);
-    }
-
-    return false;
-}
-
-void vu_set_queue_handler(VuDev *dev, VuVirtq *vq,
-                          vu_queue_handler_cb handler)
-{
-    int qidx = vq - dev->vq;
-
-    vq->handler = handler;
-    if (vq->kick_fd >= 0) {
-        if (handler) {
-            dev->set_watch(dev, vq->kick_fd, VU_WATCH_IN,
-                           vu_kick_cb, (void *)(long)qidx);
-        } else {
-            dev->remove_watch(dev, vq->kick_fd);
-        }
-    }
-}
-
-bool vu_set_queue_host_notifier(VuDev *dev, VuVirtq *vq, int fd,
-                                int size, int offset)
-{
-    int qidx = vq - dev->vq;
-    int fd_num = 0;
-    VhostUserMsg vmsg = {
-        .request = VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG,
-        .flags = VHOST_USER_VERSION | VHOST_USER_NEED_REPLY_MASK,
-        .size = sizeof(vmsg.payload.area),
-        .payload.area = {
-            .u64 = qidx & VHOST_USER_VRING_IDX_MASK,
-            .size = size,
-            .offset = offset,
-        },
-    };
-
-    if (fd == -1) {
-        vmsg.payload.area.u64 |= VHOST_USER_VRING_NOFD_MASK;
-    } else {
-        vmsg.fds[fd_num++] = fd;
-    }
-
-    vmsg.fd_num = fd_num;
-
-    if (!vu_has_protocol_feature(dev, VHOST_USER_PROTOCOL_F_SLAVE_SEND_FD)) {
-        return false;
-    }
-
-    pthread_mutex_lock(&dev->slave_mutex);
-    if (!vu_message_write(dev, dev->slave_fd, &vmsg)) {
-        pthread_mutex_unlock(&dev->slave_mutex);
-        return false;
-    }
-
-    /* Also unlocks the slave_mutex */
-    return vu_process_message_reply(dev, &vmsg);
-}
-
-static bool
-vu_set_vring_call_exec(VuDev *dev, VhostUserMsg *vmsg)
-{
-    int index = vmsg->payload.u64 & VHOST_USER_VRING_IDX_MASK;
-    bool nofd = vmsg->payload.u64 & VHOST_USER_VRING_NOFD_MASK;
-
-    DPRINT("u64: 0x%016"PRIx64"\n", vmsg->payload.u64);
-
-    if (!vu_check_queue_msg_file(dev, vmsg)) {
-        return false;
-    }
-
-    if (dev->vq[index].call_fd != -1) {
-        close(dev->vq[index].call_fd);
-        dev->vq[index].call_fd = -1;
-    }
-
-    dev->vq[index].call_fd = nofd ? -1 : vmsg->fds[0];
-
-    /* in case of I/O hang after reconnecting */
-    if (dev->vq[index].call_fd != -1 && eventfd_write(vmsg->fds[0], 1)) {
-        return -1;
-    }
-
-    DPRINT("Got call_fd: %d for vq: %d\n", dev->vq[index].call_fd, index);
-
-    return false;
-}
-
-static bool
-vu_set_vring_err_exec(VuDev *dev, VhostUserMsg *vmsg)
-{
-    int index = vmsg->payload.u64 & VHOST_USER_VRING_IDX_MASK;
-    bool nofd = vmsg->payload.u64 & VHOST_USER_VRING_NOFD_MASK;
-
-    DPRINT("u64: 0x%016"PRIx64"\n", vmsg->payload.u64);
-
-    if (!vu_check_queue_msg_file(dev, vmsg)) {
-        return false;
-    }
-
-    if (dev->vq[index].err_fd != -1) {
-        close(dev->vq[index].err_fd);
-        dev->vq[index].err_fd = -1;
-    }
-
-    dev->vq[index].err_fd = nofd ? -1 : vmsg->fds[0];
-
-    return false;
-}
-
-static bool
-vu_get_protocol_features_exec(VuDev *dev, VhostUserMsg *vmsg)
-{
-    /*
-     * Note that we support, but intentionally do not set,
-     * VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS. This means that
-     * a device implementation can return it in its callback
-     * (get_protocol_features) if it wants to use this for
-     * simulation, but it is otherwise not desirable (if even
-     * implemented by the master.)
-     */
-    uint64_t features = 1ULL << VHOST_USER_PROTOCOL_F_MQ |
-                        1ULL << VHOST_USER_PROTOCOL_F_LOG_SHMFD |
-                        1ULL << VHOST_USER_PROTOCOL_F_SLAVE_REQ |
-                        1ULL << VHOST_USER_PROTOCOL_F_HOST_NOTIFIER |
-                        1ULL << VHOST_USER_PROTOCOL_F_SLAVE_SEND_FD |
-                        1ULL << VHOST_USER_PROTOCOL_F_REPLY_ACK |
-                        1ULL << VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS;
-
-    if (have_userfault()) {
-        features |= 1ULL << VHOST_USER_PROTOCOL_F_PAGEFAULT;
-    }
-
-    if (dev->iface->get_config && dev->iface->set_config) {
-        features |= 1ULL << VHOST_USER_PROTOCOL_F_CONFIG;
-    }
-
-    if (dev->iface->get_protocol_features) {
-        features |= dev->iface->get_protocol_features(dev);
-    }
-
-    vmsg_set_reply_u64(vmsg, features);
-    return true;
-}
-
-static bool
-vu_set_protocol_features_exec(VuDev *dev, VhostUserMsg *vmsg)
-{
-    uint64_t features = vmsg->payload.u64;
-
-    DPRINT("u64: 0x%016"PRIx64"\n", features);
-
-    dev->protocol_features = vmsg->payload.u64;
-
-    if (vu_has_protocol_feature(dev,
-                                VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS) &&
-        (!vu_has_protocol_feature(dev, VHOST_USER_PROTOCOL_F_SLAVE_REQ) ||
-         !vu_has_protocol_feature(dev, VHOST_USER_PROTOCOL_F_REPLY_ACK))) {
-        /*
-         * The use case for using messages for kick/call is simulation, to make
-         * the kick and call synchronous. To actually get that behaviour, both
-         * of the other features are required.
-         * Theoretically, one could use only kick messages, or do them without
-         * having F_REPLY_ACK, but too many (possibly pending) messages on the
-         * socket will eventually cause the master to hang, to avoid this in
-         * scenarios where not desired enforce that the settings are in a way
-         * that actually enables the simulation case.
-         */
-        vu_panic(dev,
-                 "F_IN_BAND_NOTIFICATIONS requires F_SLAVE_REQ && F_REPLY_ACK");
-        return false;
-    }
-
-    if (dev->iface->set_protocol_features) {
-        dev->iface->set_protocol_features(dev, features);
-    }
-
-    return false;
-}
-
-static bool
-vu_get_queue_num_exec(VuDev *dev, VhostUserMsg *vmsg)
-{
-    vmsg_set_reply_u64(vmsg, dev->max_queues);
-    return true;
-}
-
-static bool
-vu_set_vring_enable_exec(VuDev *dev, VhostUserMsg *vmsg)
-{
-    unsigned int index = vmsg->payload.state.index;
-    unsigned int enable = vmsg->payload.state.num;
-
-    DPRINT("State.index: %u\n", index);
-    DPRINT("State.enable:   %u\n", enable);
-
-    if (index >= dev->max_queues) {
-        vu_panic(dev, "Invalid vring_enable index: %u", index);
-        return false;
-    }
-
-    dev->vq[index].enable = enable;
-    return false;
-}
-
-static bool
-vu_set_slave_req_fd(VuDev *dev, VhostUserMsg *vmsg)
-{
-    if (vmsg->fd_num != 1) {
-        vu_panic(dev, "Invalid slave_req_fd message (%d fd's)", vmsg->fd_num);
-        return false;
-    }
-
-    if (dev->slave_fd != -1) {
-        close(dev->slave_fd);
-    }
-    dev->slave_fd = vmsg->fds[0];
-    DPRINT("Got slave_fd: %d\n", vmsg->fds[0]);
-
-    return false;
-}
-
-static bool
-vu_get_config(VuDev *dev, VhostUserMsg *vmsg)
-{
-    int ret = -1;
-
-    if (dev->iface->get_config) {
-        ret = dev->iface->get_config(dev, vmsg->payload.config.region,
-                                     vmsg->payload.config.size);
-    }
-
-    if (ret) {
-        /* resize to zero to indicate an error to master */
-        vmsg->size = 0;
-    }
-
-    return true;
-}
-
-static bool
-vu_set_config(VuDev *dev, VhostUserMsg *vmsg)
-{
-    int ret = -1;
-
-    if (dev->iface->set_config) {
-        ret = dev->iface->set_config(dev, vmsg->payload.config.region,
-                                     vmsg->payload.config.offset,
-                                     vmsg->payload.config.size,
-                                     vmsg->payload.config.flags);
-        if (ret) {
-            vu_panic(dev, "Set virtio configuration space failed");
-        }
-    }
-
-    return false;
-}
-
-static bool
-vu_set_postcopy_advise(VuDev *dev, VhostUserMsg *vmsg)
-{
-    dev->postcopy_ufd = -1;
-#ifdef UFFDIO_API
-    struct uffdio_api api_struct;
-
-    dev->postcopy_ufd = syscall(__NR_userfaultfd, O_CLOEXEC | O_NONBLOCK);
-    vmsg->size = 0;
-#endif
-
-    if (dev->postcopy_ufd == -1) {
-        vu_panic(dev, "Userfaultfd not available: %s", strerror(errno));
-        goto out;
-    }
-
-#ifdef UFFDIO_API
-    api_struct.api = UFFD_API;
-    api_struct.features = 0;
-    if (ioctl(dev->postcopy_ufd, UFFDIO_API, &api_struct)) {
-        vu_panic(dev, "Failed UFFDIO_API: %s", strerror(errno));
-        close(dev->postcopy_ufd);
-        dev->postcopy_ufd = -1;
-        goto out;
-    }
-    /* TODO: Stash feature flags somewhere */
-#endif
-
-out:
-    /* Return a ufd to the QEMU */
-    vmsg->fd_num = 1;
-    vmsg->fds[0] = dev->postcopy_ufd;
-    return true; /* = send a reply */
-}
-
-static bool
-vu_set_postcopy_listen(VuDev *dev, VhostUserMsg *vmsg)
-{
-    if (dev->nregions) {
-        vu_panic(dev, "Regions already registered at postcopy-listen");
-        vmsg_set_reply_u64(vmsg, -1);
-        return true;
-    }
-    dev->postcopy_listening = true;
-
-    vmsg_set_reply_u64(vmsg, 0);
-    return true;
-}
-
-static bool
-vu_set_postcopy_end(VuDev *dev, VhostUserMsg *vmsg)
-{
-    DPRINT("%s: Entry\n", __func__);
-    dev->postcopy_listening = false;
-    if (dev->postcopy_ufd > 0) {
-        close(dev->postcopy_ufd);
-        dev->postcopy_ufd = -1;
-        DPRINT("%s: Done close\n", __func__);
-    }
-
-    vmsg_set_reply_u64(vmsg, 0);
-    DPRINT("%s: exit\n", __func__);
-    return true;
-}
-
-static inline uint64_t
-vu_inflight_queue_size(uint16_t queue_size)
-{
-    return ALIGN_UP(sizeof(VuDescStateSplit) * queue_size +
-           sizeof(uint16_t), INFLIGHT_ALIGNMENT);
-}
-
-#ifdef MFD_ALLOW_SEALING
-static void *
-memfd_alloc(const char *name, size_t size, unsigned int flags, int *fd)
-{
-    void *ptr;
-    int ret;
-
-    *fd = memfd_create(name, MFD_ALLOW_SEALING);
-    if (*fd < 0) {
-        return NULL;
-    }
-
-    ret = ftruncate(*fd, size);
-    if (ret < 0) {
-        close(*fd);
-        return NULL;
-    }
-
-    ret = fcntl(*fd, F_ADD_SEALS, flags);
-    if (ret < 0) {
-        close(*fd);
-        return NULL;
-    }
-
-    ptr = mmap(0, size, PROT_READ | PROT_WRITE, MAP_SHARED, *fd, 0);
-    if (ptr == MAP_FAILED) {
-        close(*fd);
-        return NULL;
-    }
-
-    return ptr;
-}
-#endif
-
-static bool
-vu_get_inflight_fd(VuDev *dev, VhostUserMsg *vmsg)
-{
-    int fd = -1;
-    void *addr = NULL;
-    uint64_t mmap_size;
-    uint16_t num_queues, queue_size;
-
-    if (vmsg->size != sizeof(vmsg->payload.inflight)) {
-        vu_panic(dev, "Invalid get_inflight_fd message:%d", vmsg->size);
-        vmsg->payload.inflight.mmap_size = 0;
-        return true;
-    }
-
-    num_queues = vmsg->payload.inflight.num_queues;
-    queue_size = vmsg->payload.inflight.queue_size;
-
-    DPRINT("set_inflight_fd num_queues: %"PRId16"\n", num_queues);
-    DPRINT("set_inflight_fd queue_size: %"PRId16"\n", queue_size);
-
-    mmap_size = vu_inflight_queue_size(queue_size) * num_queues;
-
-#ifdef MFD_ALLOW_SEALING
-    addr = memfd_alloc("vhost-inflight", mmap_size,
-                       F_SEAL_GROW | F_SEAL_SHRINK | F_SEAL_SEAL,
-                       &fd);
-#else
-    vu_panic(dev, "Not implemented: memfd support is missing");
-#endif
-
-    if (!addr) {
-        vu_panic(dev, "Failed to alloc vhost inflight area");
-        vmsg->payload.inflight.mmap_size = 0;
-        return true;
-    }
-
-    memset(addr, 0, mmap_size);
-
-    dev->inflight_info.addr = addr;
-    dev->inflight_info.size = vmsg->payload.inflight.mmap_size = mmap_size;
-    dev->inflight_info.fd = vmsg->fds[0] = fd;
-    vmsg->fd_num = 1;
-    vmsg->payload.inflight.mmap_offset = 0;
-
-    DPRINT("send inflight mmap_size: %"PRId64"\n",
-           vmsg->payload.inflight.mmap_size);
-    DPRINT("send inflight mmap offset: %"PRId64"\n",
-           vmsg->payload.inflight.mmap_offset);
-
-    return true;
-}
-
-static bool
-vu_set_inflight_fd(VuDev *dev, VhostUserMsg *vmsg)
-{
-    int fd, i;
-    uint64_t mmap_size, mmap_offset;
-    uint16_t num_queues, queue_size;
-    void *rc;
-
-    if (vmsg->fd_num != 1 ||
-        vmsg->size != sizeof(vmsg->payload.inflight)) {
-        vu_panic(dev, "Invalid set_inflight_fd message size:%d fds:%d",
-                 vmsg->size, vmsg->fd_num);
-        return false;
-    }
-
-    fd = vmsg->fds[0];
-    mmap_size = vmsg->payload.inflight.mmap_size;
-    mmap_offset = vmsg->payload.inflight.mmap_offset;
-    num_queues = vmsg->payload.inflight.num_queues;
-    queue_size = vmsg->payload.inflight.queue_size;
-
-    DPRINT("set_inflight_fd mmap_size: %"PRId64"\n", mmap_size);
-    DPRINT("set_inflight_fd mmap_offset: %"PRId64"\n", mmap_offset);
-    DPRINT("set_inflight_fd num_queues: %"PRId16"\n", num_queues);
-    DPRINT("set_inflight_fd queue_size: %"PRId16"\n", queue_size);
-
-    rc = mmap(0, mmap_size, PROT_READ | PROT_WRITE, MAP_SHARED,
-              fd, mmap_offset);
-
-    if (rc == MAP_FAILED) {
-        vu_panic(dev, "set_inflight_fd mmap error: %s", strerror(errno));
-        return false;
-    }
-
-    if (dev->inflight_info.fd) {
-        close(dev->inflight_info.fd);
-    }
-
-    if (dev->inflight_info.addr) {
-        munmap(dev->inflight_info.addr, dev->inflight_info.size);
-    }
-
-    dev->inflight_info.fd = fd;
-    dev->inflight_info.addr = rc;
-    dev->inflight_info.size = mmap_size;
-
-    for (i = 0; i < num_queues; i++) {
-        dev->vq[i].inflight = (VuVirtqInflight *)rc;
-        dev->vq[i].inflight->desc_num = queue_size;
-        rc = (void *)((char *)rc + vu_inflight_queue_size(queue_size));
-    }
-
-    return false;
-}
-
-static bool
-vu_handle_vring_kick(VuDev *dev, VhostUserMsg *vmsg)
-{
-    unsigned int index = vmsg->payload.state.index;
-
-    if (index >= dev->max_queues) {
-        vu_panic(dev, "Invalid queue index: %u", index);
-        return false;
-    }
-
-    DPRINT("Got kick message: handler:%p idx:%u\n",
-           dev->vq[index].handler, index);
-
-    if (!dev->vq[index].started) {
-        dev->vq[index].started = true;
-
-        if (dev->iface->queue_set_started) {
-            dev->iface->queue_set_started(dev, index, true);
-        }
-    }
-
-    if (dev->vq[index].handler) {
-        dev->vq[index].handler(dev, index);
-    }
-
-    return false;
-}
-
-static bool vu_handle_get_max_memslots(VuDev *dev, VhostUserMsg *vmsg)
-{
-    vmsg->flags = VHOST_USER_REPLY_MASK | VHOST_USER_VERSION;
-    vmsg->size  = sizeof(vmsg->payload.u64);
-    vmsg->payload.u64 = VHOST_USER_MAX_RAM_SLOTS;
-    vmsg->fd_num = 0;
-
-    if (!vu_message_write(dev, dev->sock, vmsg)) {
-        vu_panic(dev, "Failed to send max ram slots: %s\n", strerror(errno));
-    }
-
-    DPRINT("u64: 0x%016"PRIx64"\n", (uint64_t) VHOST_USER_MAX_RAM_SLOTS);
-
-    return false;
-}
-
-static bool
-vu_process_message(VuDev *dev, VhostUserMsg *vmsg)
-{
-    int do_reply = 0;
-
-    /* Print out generic part of the request. */
-    DPRINT("================ Vhost user message ================\n");
-    DPRINT("Request: %s (%d)\n", vu_request_to_string(vmsg->request),
-           vmsg->request);
-    DPRINT("Flags:   0x%x\n", vmsg->flags);
-    DPRINT("Size:    %u\n", vmsg->size);
-
-    if (vmsg->fd_num) {
-        int i;
-        DPRINT("Fds:");
-        for (i = 0; i < vmsg->fd_num; i++) {
-            DPRINT(" %d", vmsg->fds[i]);
-        }
-        DPRINT("\n");
-    }
-
-    if (dev->iface->process_msg &&
-        dev->iface->process_msg(dev, vmsg, &do_reply)) {
-        return do_reply;
-    }
-
-    switch (vmsg->request) {
-    case VHOST_USER_GET_FEATURES:
-        return vu_get_features_exec(dev, vmsg);
-    case VHOST_USER_SET_FEATURES:
-        return vu_set_features_exec(dev, vmsg);
-    case VHOST_USER_GET_PROTOCOL_FEATURES:
-        return vu_get_protocol_features_exec(dev, vmsg);
-    case VHOST_USER_SET_PROTOCOL_FEATURES:
-        return vu_set_protocol_features_exec(dev, vmsg);
-    case VHOST_USER_SET_OWNER:
-        return vu_set_owner_exec(dev, vmsg);
-    case VHOST_USER_RESET_OWNER:
-        return vu_reset_device_exec(dev, vmsg);
-    case VHOST_USER_SET_MEM_TABLE:
-        return vu_set_mem_table_exec(dev, vmsg);
-    case VHOST_USER_SET_LOG_BASE:
-        return vu_set_log_base_exec(dev, vmsg);
-    case VHOST_USER_SET_LOG_FD:
-        return vu_set_log_fd_exec(dev, vmsg);
-    case VHOST_USER_SET_VRING_NUM:
-        return vu_set_vring_num_exec(dev, vmsg);
-    case VHOST_USER_SET_VRING_ADDR:
-        return vu_set_vring_addr_exec(dev, vmsg);
-    case VHOST_USER_SET_VRING_BASE:
-        return vu_set_vring_base_exec(dev, vmsg);
-    case VHOST_USER_GET_VRING_BASE:
-        return vu_get_vring_base_exec(dev, vmsg);
-    case VHOST_USER_SET_VRING_KICK:
-        return vu_set_vring_kick_exec(dev, vmsg);
-    case VHOST_USER_SET_VRING_CALL:
-        return vu_set_vring_call_exec(dev, vmsg);
-    case VHOST_USER_SET_VRING_ERR:
-        return vu_set_vring_err_exec(dev, vmsg);
-    case VHOST_USER_GET_QUEUE_NUM:
-        return vu_get_queue_num_exec(dev, vmsg);
-    case VHOST_USER_SET_VRING_ENABLE:
-        return vu_set_vring_enable_exec(dev, vmsg);
-    case VHOST_USER_SET_SLAVE_REQ_FD:
-        return vu_set_slave_req_fd(dev, vmsg);
-    case VHOST_USER_GET_CONFIG:
-        return vu_get_config(dev, vmsg);
-    case VHOST_USER_SET_CONFIG:
-        return vu_set_config(dev, vmsg);
-    case VHOST_USER_NONE:
-        /* if you need processing before exit, override iface->process_msg */
-        exit(0);
-    case VHOST_USER_POSTCOPY_ADVISE:
-        return vu_set_postcopy_advise(dev, vmsg);
-    case VHOST_USER_POSTCOPY_LISTEN:
-        return vu_set_postcopy_listen(dev, vmsg);
-    case VHOST_USER_POSTCOPY_END:
-        return vu_set_postcopy_end(dev, vmsg);
-    case VHOST_USER_GET_INFLIGHT_FD:
-        return vu_get_inflight_fd(dev, vmsg);
-    case VHOST_USER_SET_INFLIGHT_FD:
-        return vu_set_inflight_fd(dev, vmsg);
-    case VHOST_USER_VRING_KICK:
-        return vu_handle_vring_kick(dev, vmsg);
-    case VHOST_USER_GET_MAX_MEM_SLOTS:
-        return vu_handle_get_max_memslots(dev, vmsg);
-    case VHOST_USER_ADD_MEM_REG:
-        return vu_add_mem_reg(dev, vmsg);
-    case VHOST_USER_REM_MEM_REG:
-        return vu_rem_mem_reg(dev, vmsg);
-    default:
-        vmsg_close_fds(vmsg);
-        vu_panic(dev, "Unhandled request: %d", vmsg->request);
-    }
-
-    return false;
-}
-
-bool
-vu_dispatch(VuDev *dev)
-{
-    VhostUserMsg vmsg = { 0, };
-    int reply_requested;
-    bool need_reply, success = false;
-
-    if (!dev->read_msg(dev, dev->sock, &vmsg)) {
-        goto end;
-    }
-
-    need_reply = vmsg.flags & VHOST_USER_NEED_REPLY_MASK;
-
-    reply_requested = vu_process_message(dev, &vmsg);
-    if (!reply_requested && need_reply) {
-        vmsg_set_reply_u64(&vmsg, 0);
-        reply_requested = 1;
-    }
-
-    if (!reply_requested) {
-        success = true;
-        goto end;
-    }
-
-    if (!vu_send_reply(dev, dev->sock, &vmsg)) {
-        goto end;
-    }
-
-    success = true;
-
-end:
-    free(vmsg.data);
-    return success;
-}
-
-void
-vu_deinit(VuDev *dev)
-{
-    int i;
-
-    for (i = 0; i < dev->nregions; i++) {
-        VuDevRegion *r = &dev->regions[i];
-        void *m = (void *) (uintptr_t) r->mmap_addr;
-        if (m != MAP_FAILED) {
-            munmap(m, r->size + r->mmap_offset);
-        }
-    }
-    dev->nregions = 0;
-
-    for (i = 0; i < dev->max_queues; i++) {
-        VuVirtq *vq = &dev->vq[i];
-
-        if (vq->call_fd != -1) {
-            close(vq->call_fd);
-            vq->call_fd = -1;
-        }
-
-        if (vq->kick_fd != -1) {
-            dev->remove_watch(dev, vq->kick_fd);
-            close(vq->kick_fd);
-            vq->kick_fd = -1;
-        }
-
-        if (vq->err_fd != -1) {
-            close(vq->err_fd);
-            vq->err_fd = -1;
-        }
-
-        if (vq->resubmit_list) {
-            free(vq->resubmit_list);
-            vq->resubmit_list = NULL;
-        }
-
-        vq->inflight = NULL;
-    }
-
-    if (dev->inflight_info.addr) {
-        munmap(dev->inflight_info.addr, dev->inflight_info.size);
-        dev->inflight_info.addr = NULL;
-    }
-
-    if (dev->inflight_info.fd > 0) {
-        close(dev->inflight_info.fd);
-        dev->inflight_info.fd = -1;
-    }
-
-    vu_close_log(dev);
-    if (dev->slave_fd != -1) {
-        close(dev->slave_fd);
-        dev->slave_fd = -1;
-    }
-    pthread_mutex_destroy(&dev->slave_mutex);
-
-    if (dev->sock != -1) {
-        close(dev->sock);
-    }
-
-    free(dev->vq);
-    dev->vq = NULL;
-}
-
-bool
-vu_init(VuDev *dev,
-        uint16_t max_queues,
-        int socket,
-        vu_panic_cb panic,
-        vu_read_msg_cb read_msg,
-        vu_set_watch_cb set_watch,
-        vu_remove_watch_cb remove_watch,
-        const VuDevIface *iface)
-{
-    uint16_t i;
-
-    assert(max_queues > 0);
-    assert(socket >= 0);
-    assert(set_watch);
-    assert(remove_watch);
-    assert(iface);
-    assert(panic);
-
-    memset(dev, 0, sizeof(*dev));
-
-    dev->sock = socket;
-    dev->panic = panic;
-    dev->read_msg = read_msg ? read_msg : vu_message_read_default;
-    dev->set_watch = set_watch;
-    dev->remove_watch = remove_watch;
-    dev->iface = iface;
-    dev->log_call_fd = -1;
-    pthread_mutex_init(&dev->slave_mutex, NULL);
-    dev->slave_fd = -1;
-    dev->max_queues = max_queues;
-
-    dev->vq = malloc(max_queues * sizeof(dev->vq[0]));
-    if (!dev->vq) {
-        DPRINT("%s: failed to malloc virtqueues\n", __func__);
-        return false;
-    }
-
-    for (i = 0; i < max_queues; i++) {
-        dev->vq[i] = (VuVirtq) {
-            .call_fd = -1, .kick_fd = -1, .err_fd = -1,
-            .notification = true,
-        };
-    }
-
-    return true;
-}
-
-VuVirtq *
-vu_get_queue(VuDev *dev, int qidx)
-{
-    assert(qidx < dev->max_queues);
-    return &dev->vq[qidx];
-}
-
-bool
-vu_queue_enabled(VuDev *dev, VuVirtq *vq)
-{
-    return vq->enable;
-}
-
-bool
-vu_queue_started(const VuDev *dev, const VuVirtq *vq)
-{
-    return vq->started;
-}
-
-static inline uint16_t
-vring_avail_flags(VuVirtq *vq)
-{
-    return le16toh(vq->vring.avail->flags);
-}
-
-static inline uint16_t
-vring_avail_idx(VuVirtq *vq)
-{
-    vq->shadow_avail_idx = le16toh(vq->vring.avail->idx);
-
-    return vq->shadow_avail_idx;
-}
-
-static inline uint16_t
-vring_avail_ring(VuVirtq *vq, int i)
-{
-    return le16toh(vq->vring.avail->ring[i]);
-}
-
-static inline uint16_t
-vring_get_used_event(VuVirtq *vq)
-{
-    return vring_avail_ring(vq, vq->vring.num);
-}
-
-static int
-virtqueue_num_heads(VuDev *dev, VuVirtq *vq, unsigned int idx)
-{
-    uint16_t num_heads = vring_avail_idx(vq) - idx;
-
-    /* Check it isn't doing very strange things with descriptor numbers. */
-    if (num_heads > vq->vring.num) {
-        vu_panic(dev, "Guest moved used index from %u to %u",
-                 idx, vq->shadow_avail_idx);
-        return -1;
-    }
-    if (num_heads) {
-        /* On success, callers read a descriptor at vq->last_avail_idx.
-         * Make sure descriptor read does not bypass avail index read. */
-        smp_rmb();
-    }
-
-    return num_heads;
-}
-
-static bool
-virtqueue_get_head(VuDev *dev, VuVirtq *vq,
-                   unsigned int idx, unsigned int *head)
-{
-    /* Grab the next descriptor number they're advertising, and increment
-     * the index we've seen. */
-    *head = vring_avail_ring(vq, idx % vq->vring.num);
-
-    /* If their number is silly, that's a fatal mistake. */
-    if (*head >= vq->vring.num) {
-        vu_panic(dev, "Guest says index %u is available", *head);
-        return false;
-    }
-
-    return true;
-}
-
-static int
-virtqueue_read_indirect_desc(VuDev *dev, struct vring_desc *desc,
-                             uint64_t addr, size_t len)
-{
-    struct vring_desc *ori_desc;
-    uint64_t read_len;
-
-    if (len > (VIRTQUEUE_MAX_SIZE * sizeof(struct vring_desc))) {
-        return -1;
-    }
-
-    if (len == 0) {
-        return -1;
-    }
-
-    while (len) {
-        read_len = len;
-        ori_desc = vu_gpa_to_va(dev, &read_len, addr);
-        if (!ori_desc) {
-            return -1;
-        }
-
-        memcpy(desc, ori_desc, read_len);
-        len -= read_len;
-        addr += read_len;
-        desc += read_len;
-    }
-
-    return 0;
-}
-
-enum {
-    VIRTQUEUE_READ_DESC_ERROR = -1,
-    VIRTQUEUE_READ_DESC_DONE = 0,   /* end of chain */
-    VIRTQUEUE_READ_DESC_MORE = 1,   /* more buffers in chain */
-};
-
-static int
-virtqueue_read_next_desc(VuDev *dev, struct vring_desc *desc,
-                         int i, unsigned int max, unsigned int *next)
-{
-    /* If this descriptor says it doesn't chain, we're done. */
-    if (!(le16toh(desc[i].flags) & VRING_DESC_F_NEXT)) {
-        return VIRTQUEUE_READ_DESC_DONE;
-    }
-
-    /* Check they're not leading us off end of descriptors. */
-    *next = le16toh(desc[i].next);
-    /* Make sure compiler knows to grab that: we don't want it changing! */
-    smp_wmb();
-
-    if (*next >= max) {
-        vu_panic(dev, "Desc next is %u", *next);
-        return VIRTQUEUE_READ_DESC_ERROR;
-    }
-
-    return VIRTQUEUE_READ_DESC_MORE;
-}
-
-void
-vu_queue_get_avail_bytes(VuDev *dev, VuVirtq *vq, unsigned int *in_bytes,
-                         unsigned int *out_bytes,
-                         unsigned max_in_bytes, unsigned max_out_bytes)
-{
-    unsigned int idx;
-    unsigned int total_bufs, in_total, out_total;
-    int rc;
-
-    idx = vq->last_avail_idx;
-
-    total_bufs = in_total = out_total = 0;
-    if (unlikely(dev->broken) ||
-        unlikely(!vq->vring.avail)) {
-        goto done;
-    }
-
-    while ((rc = virtqueue_num_heads(dev, vq, idx)) > 0) {
-        unsigned int max, desc_len, num_bufs, indirect = 0;
-        uint64_t desc_addr, read_len;
-        struct vring_desc *desc;
-        struct vring_desc desc_buf[VIRTQUEUE_MAX_SIZE];
-        unsigned int i;
-
-        max = vq->vring.num;
-        num_bufs = total_bufs;
-        if (!virtqueue_get_head(dev, vq, idx++, &i)) {
-            goto err;
-        }
-        desc = vq->vring.desc;
-
-        if (le16toh(desc[i].flags) & VRING_DESC_F_INDIRECT) {
-            if (le32toh(desc[i].len) % sizeof(struct vring_desc)) {
-                vu_panic(dev, "Invalid size for indirect buffer table");
-                goto err;
-            }
-
-            /* If we've got too many, that implies a descriptor loop. */
-            if (num_bufs >= max) {
-                vu_panic(dev, "Looped descriptor");
-                goto err;
-            }
-
-            /* loop over the indirect descriptor table */
-            indirect = 1;
-            desc_addr = le64toh(desc[i].addr);
-            desc_len = le32toh(desc[i].len);
-            max = desc_len / sizeof(struct vring_desc);
-            read_len = desc_len;
-            desc = vu_gpa_to_va(dev, &read_len, desc_addr);
-            if (unlikely(desc && read_len != desc_len)) {
-                /* Failed to use zero copy */
-                desc = NULL;
-                if (!virtqueue_read_indirect_desc(dev, desc_buf,
-                                                  desc_addr,
-                                                  desc_len)) {
-                    desc = desc_buf;
-                }
-            }
-            if (!desc) {
-                vu_panic(dev, "Invalid indirect buffer table");
-                goto err;
-            }
-            num_bufs = i = 0;
-        }
-
-        do {
-            /* If we've got too many, that implies a descriptor loop. */
-            if (++num_bufs > max) {
-                vu_panic(dev, "Looped descriptor");
-                goto err;
-            }
-
-            if (le16toh(desc[i].flags) & VRING_DESC_F_WRITE) {
-                in_total += le32toh(desc[i].len);
-            } else {
-                out_total += le32toh(desc[i].len);
-            }
-            if (in_total >= max_in_bytes && out_total >= max_out_bytes) {
-                goto done;
-            }
-            rc = virtqueue_read_next_desc(dev, desc, i, max, &i);
-        } while (rc == VIRTQUEUE_READ_DESC_MORE);
-
-        if (rc == VIRTQUEUE_READ_DESC_ERROR) {
-            goto err;
-        }
-
-        if (!indirect) {
-            total_bufs = num_bufs;
-        } else {
-            total_bufs++;
-        }
-    }
-    if (rc < 0) {
-        goto err;
-    }
-done:
-    if (in_bytes) {
-        *in_bytes = in_total;
-    }
-    if (out_bytes) {
-        *out_bytes = out_total;
-    }
-    return;
-
-err:
-    in_total = out_total = 0;
-    goto done;
-}
-
-bool
-vu_queue_avail_bytes(VuDev *dev, VuVirtq *vq, unsigned int in_bytes,
-                     unsigned int out_bytes)
-{
-    unsigned int in_total, out_total;
-
-    vu_queue_get_avail_bytes(dev, vq, &in_total, &out_total,
-                             in_bytes, out_bytes);
-
-    return in_bytes <= in_total && out_bytes <= out_total;
-}
-
-/* Fetch avail_idx from VQ memory only when we really need to know if
- * guest has added some buffers. */
-bool
-vu_queue_empty(VuDev *dev, VuVirtq *vq)
-{
-    if (unlikely(dev->broken) ||
-        unlikely(!vq->vring.avail)) {
-        return true;
-    }
-
-    if (vq->shadow_avail_idx != vq->last_avail_idx) {
-        return false;
-    }
-
-    return vring_avail_idx(vq) == vq->last_avail_idx;
-}
-
-static bool
-vring_notify(VuDev *dev, VuVirtq *vq)
-{
-    uint16_t old, new;
-    bool v;
-
-    /* We need to expose used array entries before checking used event. */
-    smp_mb();
-
-    /* Always notify when queue is empty (when feature acknowledge) */
-    if (vu_has_feature(dev, VIRTIO_F_NOTIFY_ON_EMPTY) &&
-        !vq->inuse && vu_queue_empty(dev, vq)) {
-        return true;
-    }
-
-    if (!vu_has_feature(dev, VIRTIO_RING_F_EVENT_IDX)) {
-        return !(vring_avail_flags(vq) & VRING_AVAIL_F_NO_INTERRUPT);
-    }
-
-    v = vq->signalled_used_valid;
-    vq->signalled_used_valid = true;
-    old = vq->signalled_used;
-    new = vq->signalled_used = vq->used_idx;
-    return !v || vring_need_event(vring_get_used_event(vq), new, old);
-}
-
-static void _vu_queue_notify(VuDev *dev, VuVirtq *vq, bool sync)
-{
-    if (unlikely(dev->broken) ||
-        unlikely(!vq->vring.avail)) {
-        return;
-    }
-
-    if (!vring_notify(dev, vq)) {
-        DPRINT("skipped notify...\n");
-        return;
-    }
-
-    if (vq->call_fd < 0 &&
-        vu_has_protocol_feature(dev,
-                                VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS) &&
-        vu_has_protocol_feature(dev, VHOST_USER_PROTOCOL_F_SLAVE_REQ)) {
-        VhostUserMsg vmsg = {
-            .request = VHOST_USER_SLAVE_VRING_CALL,
-            .flags = VHOST_USER_VERSION,
-            .size = sizeof(vmsg.payload.state),
-            .payload.state = {
-                .index = vq - dev->vq,
-            },
-        };
-        bool ack = sync &&
-                   vu_has_protocol_feature(dev,
-                                           VHOST_USER_PROTOCOL_F_REPLY_ACK);
-
-        if (ack) {
-            vmsg.flags |= VHOST_USER_NEED_REPLY_MASK;
-        }
-
-        vu_message_write(dev, dev->slave_fd, &vmsg);
-        if (ack) {
-            vu_message_read_default(dev, dev->slave_fd, &vmsg);
-        }
-        return;
-    }
-
-    if (eventfd_write(vq->call_fd, 1) < 0) {
-        vu_panic(dev, "Error writing eventfd: %s", strerror(errno));
-    }
-}
-
-void vu_queue_notify(VuDev *dev, VuVirtq *vq)
-{
-    _vu_queue_notify(dev, vq, false);
-}
-
-void vu_queue_notify_sync(VuDev *dev, VuVirtq *vq)
-{
-    _vu_queue_notify(dev, vq, true);
-}
-
-static inline void
-vring_used_flags_set_bit(VuVirtq *vq, int mask)
-{
-    uint16_t *flags;
-
-    flags = (uint16_t *)((char*)vq->vring.used +
-                         offsetof(struct vring_used, flags));
-    *flags = htole16(le16toh(*flags) | mask);
-}
-
-static inline void
-vring_used_flags_unset_bit(VuVirtq *vq, int mask)
-{
-    uint16_t *flags;
-
-    flags = (uint16_t *)((char*)vq->vring.used +
-                         offsetof(struct vring_used, flags));
-    *flags = htole16(le16toh(*flags) & ~mask);
-}
-
-static inline void
-vring_set_avail_event(VuVirtq *vq, uint16_t val)
-{
-    uint16_t *avail;
-
-    if (!vq->notification) {
-        return;
-    }
-
-    avail = (uint16_t *)&vq->vring.used->ring[vq->vring.num];
-    *avail = htole16(val);
-}
-
-void
-vu_queue_set_notification(VuDev *dev, VuVirtq *vq, int enable)
-{
-    vq->notification = enable;
-    if (vu_has_feature(dev, VIRTIO_RING_F_EVENT_IDX)) {
-        vring_set_avail_event(vq, vring_avail_idx(vq));
-    } else if (enable) {
-        vring_used_flags_unset_bit(vq, VRING_USED_F_NO_NOTIFY);
-    } else {
-        vring_used_flags_set_bit(vq, VRING_USED_F_NO_NOTIFY);
-    }
-    if (enable) {
-        /* Expose avail event/used flags before caller checks the avail idx. */
-        smp_mb();
-    }
-}
-
-static bool
-virtqueue_map_desc(VuDev *dev,
-                   unsigned int *p_num_sg, struct iovec *iov,
-                   unsigned int max_num_sg, bool is_write,
-                   uint64_t pa, size_t sz)
-{
-    unsigned num_sg = *p_num_sg;
-
-    assert(num_sg <= max_num_sg);
-
-    if (!sz) {
-        vu_panic(dev, "virtio: zero sized buffers are not allowed");
-        return false;
-    }
-
-    while (sz) {
-        uint64_t len = sz;
-
-        if (num_sg == max_num_sg) {
-            vu_panic(dev, "virtio: too many descriptors in indirect table");
-            return false;
-        }
-
-        iov[num_sg].iov_base = vu_gpa_to_va(dev, &len, pa);
-        if (iov[num_sg].iov_base == NULL) {
-            vu_panic(dev, "virtio: invalid address for buffers");
-            return false;
-        }
-        iov[num_sg].iov_len = len;
-        num_sg++;
-        sz -= len;
-        pa += len;
-    }
-
-    *p_num_sg = num_sg;
-    return true;
-}
-
-static void *
-virtqueue_alloc_element(size_t sz,
-                                     unsigned out_num, unsigned in_num)
-{
-    VuVirtqElement *elem;
-    size_t in_sg_ofs = ALIGN_UP(sz, __alignof__(elem->in_sg[0]));
-    size_t out_sg_ofs = in_sg_ofs + in_num * sizeof(elem->in_sg[0]);
-    size_t out_sg_end = out_sg_ofs + out_num * sizeof(elem->out_sg[0]);
-
-    assert(sz >= sizeof(VuVirtqElement));
-    elem = malloc(out_sg_end);
-    elem->out_num = out_num;
-    elem->in_num = in_num;
-    elem->in_sg = (void *)elem + in_sg_ofs;
-    elem->out_sg = (void *)elem + out_sg_ofs;
-    return elem;
-}
-
-static void *
-vu_queue_map_desc(VuDev *dev, VuVirtq *vq, unsigned int idx, size_t sz)
-{
-    struct vring_desc *desc = vq->vring.desc;
-    uint64_t desc_addr, read_len;
-    unsigned int desc_len;
-    unsigned int max = vq->vring.num;
-    unsigned int i = idx;
-    VuVirtqElement *elem;
-    unsigned int out_num = 0, in_num = 0;
-    struct iovec iov[VIRTQUEUE_MAX_SIZE];
-    struct vring_desc desc_buf[VIRTQUEUE_MAX_SIZE];
-    int rc;
-
-    if (le16toh(desc[i].flags) & VRING_DESC_F_INDIRECT) {
-        if (le32toh(desc[i].len) % sizeof(struct vring_desc)) {
-            vu_panic(dev, "Invalid size for indirect buffer table");
-            return NULL;
-        }
-
-        /* loop over the indirect descriptor table */
-        desc_addr = le64toh(desc[i].addr);
-        desc_len = le32toh(desc[i].len);
-        max = desc_len / sizeof(struct vring_desc);
-        read_len = desc_len;
-        desc = vu_gpa_to_va(dev, &read_len, desc_addr);
-        if (unlikely(desc && read_len != desc_len)) {
-            /* Failed to use zero copy */
-            desc = NULL;
-            if (!virtqueue_read_indirect_desc(dev, desc_buf,
-                                              desc_addr,
-                                              desc_len)) {
-                desc = desc_buf;
-            }
-        }
-        if (!desc) {
-            vu_panic(dev, "Invalid indirect buffer table");
-            return NULL;
-        }
-        i = 0;
-    }
-
-    /* Collect all the descriptors */
-    do {
-        if (le16toh(desc[i].flags) & VRING_DESC_F_WRITE) {
-            if (!virtqueue_map_desc(dev, &in_num, iov + out_num,
-                               VIRTQUEUE_MAX_SIZE - out_num, true,
-                               le64toh(desc[i].addr),
-                               le32toh(desc[i].len))) {
-                return NULL;
-            }
-        } else {
-            if (in_num) {
-                vu_panic(dev, "Incorrect order for descriptors");
-                return NULL;
-            }
-            if (!virtqueue_map_desc(dev, &out_num, iov,
-                               VIRTQUEUE_MAX_SIZE, false,
-                               le64toh(desc[i].addr),
-                               le32toh(desc[i].len))) {
-                return NULL;
-            }
-        }
-
-        /* If we've got too many, that implies a descriptor loop. */
-        if ((in_num + out_num) > max) {
-            vu_panic(dev, "Looped descriptor");
-            return NULL;
-        }
-        rc = virtqueue_read_next_desc(dev, desc, i, max, &i);
-    } while (rc == VIRTQUEUE_READ_DESC_MORE);
-
-    if (rc == VIRTQUEUE_READ_DESC_ERROR) {
-        vu_panic(dev, "read descriptor error");
-        return NULL;
-    }
-
-    /* Now copy what we have collected and mapped */
-    elem = virtqueue_alloc_element(sz, out_num, in_num);
-    elem->index = idx;
-    for (i = 0; i < out_num; i++) {
-        elem->out_sg[i] = iov[i];
-    }
-    for (i = 0; i < in_num; i++) {
-        elem->in_sg[i] = iov[out_num + i];
-    }
-
-    return elem;
-}
-
-static int
-vu_queue_inflight_get(VuDev *dev, VuVirtq *vq, int desc_idx)
-{
-    if (!vu_has_protocol_feature(dev, VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD)) {
-        return 0;
-    }
-
-    if (unlikely(!vq->inflight)) {
-        return -1;
-    }
-
-    vq->inflight->desc[desc_idx].counter = vq->counter++;
-    vq->inflight->desc[desc_idx].inflight = 1;
-
-    return 0;
-}
-
-static int
-vu_queue_inflight_pre_put(VuDev *dev, VuVirtq *vq, int desc_idx)
-{
-    if (!vu_has_protocol_feature(dev, VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD)) {
-        return 0;
-    }
-
-    if (unlikely(!vq->inflight)) {
-        return -1;
-    }
-
-    vq->inflight->last_batch_head = desc_idx;
-
-    return 0;
-}
-
-static int
-vu_queue_inflight_post_put(VuDev *dev, VuVirtq *vq, int desc_idx)
-{
-    if (!vu_has_protocol_feature(dev, VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD)) {
-        return 0;
-    }
-
-    if (unlikely(!vq->inflight)) {
-        return -1;
-    }
-
-    barrier();
-
-    vq->inflight->desc[desc_idx].inflight = 0;
-
-    barrier();
-
-    vq->inflight->used_idx = vq->used_idx;
-
-    return 0;
-}
-
-void *
-vu_queue_pop(VuDev *dev, VuVirtq *vq, size_t sz)
-{
-    int i;
-    unsigned int head;
-    VuVirtqElement *elem;
-
-    if (unlikely(dev->broken) ||
-        unlikely(!vq->vring.avail)) {
-        return NULL;
-    }
-
-    if (unlikely(vq->resubmit_list && vq->resubmit_num > 0)) {
-        i = (--vq->resubmit_num);
-        elem = vu_queue_map_desc(dev, vq, vq->resubmit_list[i].index, sz);
-
-        if (!vq->resubmit_num) {
-            free(vq->resubmit_list);
-            vq->resubmit_list = NULL;
-        }
-
-        return elem;
-    }
-
-    if (vu_queue_empty(dev, vq)) {
-        return NULL;
-    }
-    /*
-     * Needed after virtio_queue_empty(), see comment in
-     * virtqueue_num_heads().
-     */
-    smp_rmb();
-
-    if (vq->inuse >= vq->vring.num) {
-        vu_panic(dev, "Virtqueue size exceeded");
-        return NULL;
-    }
-
-    if (!virtqueue_get_head(dev, vq, vq->last_avail_idx++, &head)) {
-        return NULL;
-    }
-
-    if (vu_has_feature(dev, VIRTIO_RING_F_EVENT_IDX)) {
-        vring_set_avail_event(vq, vq->last_avail_idx);
-    }
-
-    elem = vu_queue_map_desc(dev, vq, head, sz);
-
-    if (!elem) {
-        return NULL;
-    }
-
-    vq->inuse++;
-
-    vu_queue_inflight_get(dev, vq, head);
-
-    return elem;
-}
-
-static void
-vu_queue_detach_element(VuDev *dev, VuVirtq *vq, VuVirtqElement *elem,
-                        size_t len)
-{
-    vq->inuse--;
-    /* unmap, when DMA support is added */
-}
-
-void
-vu_queue_unpop(VuDev *dev, VuVirtq *vq, VuVirtqElement *elem,
-               size_t len)
-{
-    vq->last_avail_idx--;
-    vu_queue_detach_element(dev, vq, elem, len);
-}
-
-bool
-vu_queue_rewind(VuDev *dev, VuVirtq *vq, unsigned int num)
-{
-    if (num > vq->inuse) {
-        return false;
-    }
-    vq->last_avail_idx -= num;
-    vq->inuse -= num;
-    return true;
-}
-
-static inline
-void vring_used_write(VuDev *dev, VuVirtq *vq,
-                      struct vring_used_elem *uelem, int i)
-{
-    struct vring_used *used = vq->vring.used;
-
-    used->ring[i] = *uelem;
-    vu_log_write(dev, vq->vring.log_guest_addr +
-                 offsetof(struct vring_used, ring[i]),
-                 sizeof(used->ring[i]));
-}
-
-
-static void
-vu_log_queue_fill(VuDev *dev, VuVirtq *vq,
-                  const VuVirtqElement *elem,
-                  unsigned int len)
-{
-    struct vring_desc *desc = vq->vring.desc;
-    unsigned int i, max, min, desc_len;
-    uint64_t desc_addr, read_len;
-    struct vring_desc desc_buf[VIRTQUEUE_MAX_SIZE];
-    unsigned num_bufs = 0;
-
-    max = vq->vring.num;
-    i = elem->index;
-
-    if (le16toh(desc[i].flags) & VRING_DESC_F_INDIRECT) {
-        if (le32toh(desc[i].len) % sizeof(struct vring_desc)) {
-            vu_panic(dev, "Invalid size for indirect buffer table");
-            return;
-        }
-
-        /* loop over the indirect descriptor table */
-        desc_addr = le64toh(desc[i].addr);
-        desc_len = le32toh(desc[i].len);
-        max = desc_len / sizeof(struct vring_desc);
-        read_len = desc_len;
-        desc = vu_gpa_to_va(dev, &read_len, desc_addr);
-        if (unlikely(desc && read_len != desc_len)) {
-            /* Failed to use zero copy */
-            desc = NULL;
-            if (!virtqueue_read_indirect_desc(dev, desc_buf,
-                                              desc_addr,
-                                              desc_len)) {
-                desc = desc_buf;
-            }
-        }
-        if (!desc) {
-            vu_panic(dev, "Invalid indirect buffer table");
-            return;
-        }
-        i = 0;
-    }
-
-    do {
-        if (++num_bufs > max) {
-            vu_panic(dev, "Looped descriptor");
-            return;
-        }
-
-        if (le16toh(desc[i].flags) & VRING_DESC_F_WRITE) {
-            min = MIN(le32toh(desc[i].len), len);
-            vu_log_write(dev, le64toh(desc[i].addr), min);
-            len -= min;
-        }
-
-    } while (len > 0 &&
-             (virtqueue_read_next_desc(dev, desc, i, max, &i)
-              == VIRTQUEUE_READ_DESC_MORE));
-}
-
-void
-vu_queue_fill(VuDev *dev, VuVirtq *vq,
-              const VuVirtqElement *elem,
-              unsigned int len, unsigned int idx)
-{
-    struct vring_used_elem uelem;
-
-    if (unlikely(dev->broken) ||
-        unlikely(!vq->vring.avail)) {
-        return;
-    }
-
-    vu_log_queue_fill(dev, vq, elem, len);
-
-    idx = (idx + vq->used_idx) % vq->vring.num;
-
-    uelem.id = htole32(elem->index);
-    uelem.len = htole32(len);
-    vring_used_write(dev, vq, &uelem, idx);
-}
-
-static inline
-void vring_used_idx_set(VuDev *dev, VuVirtq *vq, uint16_t val)
-{
-    vq->vring.used->idx = htole16(val);
-    vu_log_write(dev,
-                 vq->vring.log_guest_addr + offsetof(struct vring_used, idx),
-                 sizeof(vq->vring.used->idx));
-
-    vq->used_idx = val;
-}
-
-void
-vu_queue_flush(VuDev *dev, VuVirtq *vq, unsigned int count)
-{
-    uint16_t old, new;
-
-    if (unlikely(dev->broken) ||
-        unlikely(!vq->vring.avail)) {
-        return;
-    }
-
-    /* Make sure buffer is written before we update index. */
-    smp_wmb();
-
-    old = vq->used_idx;
-    new = old + count;
-    vring_used_idx_set(dev, vq, new);
-    vq->inuse -= count;
-    if (unlikely((int16_t)(new - vq->signalled_used) < (uint16_t)(new - old))) {
-        vq->signalled_used_valid = false;
-    }
-}
-
-void
-vu_queue_push(VuDev *dev, VuVirtq *vq,
-              const VuVirtqElement *elem, unsigned int len)
-{
-    vu_queue_fill(dev, vq, elem, len, 0);
-    vu_queue_inflight_pre_put(dev, vq, elem->index);
-    vu_queue_flush(dev, vq, 1);
-    vu_queue_inflight_post_put(dev, vq, elem->index);
-}