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-rw-r--r--subprojects/libvhost-user/libvhost-user-glib.c176
-rw-r--r--subprojects/libvhost-user/libvhost-user-glib.h36
-rw-r--r--subprojects/libvhost-user/libvhost-user.c2883
-rw-r--r--subprojects/libvhost-user/libvhost-user.h690
-rw-r--r--subprojects/libvhost-user/meson.build20
5 files changed, 3805 insertions, 0 deletions
diff --git a/subprojects/libvhost-user/libvhost-user-glib.c b/subprojects/libvhost-user/libvhost-user-glib.c
new file mode 100644
index 0000000000..efc9d814e3
--- /dev/null
+++ b/subprojects/libvhost-user/libvhost-user-glib.c
@@ -0,0 +1,176 @@
+/*
+ * Vhost User library
+ *
+ * Copyright (c) 2016 Nutanix Inc. All rights reserved.
+ * Copyright (c) 2017 Red Hat, Inc.
+ *
+ * Authors:
+ * Marc-André Lureau <mlureau@redhat.com>
+ * Felipe Franciosi <felipe@nutanix.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.
+ */
+
+#include "libvhost-user-glib.h"
+
+#ifndef container_of
+#define container_of(ptr, type, member) \
+ __extension__({ \
+ void *__mptr = (void *)(ptr); \
+ ((type *)(__mptr - offsetof(type, member))); \
+ })
+#endif
+
+/* glib event loop integration for libvhost-user and misc callbacks */
+
+G_STATIC_ASSERT((int)G_IO_IN == (int)VU_WATCH_IN);
+G_STATIC_ASSERT((int)G_IO_OUT == (int)VU_WATCH_OUT);
+G_STATIC_ASSERT((int)G_IO_PRI == (int)VU_WATCH_PRI);
+G_STATIC_ASSERT((int)G_IO_ERR == (int)VU_WATCH_ERR);
+G_STATIC_ASSERT((int)G_IO_HUP == (int)VU_WATCH_HUP);
+
+typedef struct VugSrc {
+ GSource parent;
+ VuDev *dev;
+ GPollFD gfd;
+} VugSrc;
+
+static gboolean
+vug_src_prepare(GSource *gsrc, gint *timeout)
+{
+ g_assert(timeout);
+
+ *timeout = -1;
+ return FALSE;
+}
+
+static gboolean
+vug_src_check(GSource *gsrc)
+{
+ VugSrc *src = (VugSrc *)gsrc;
+
+ g_assert(src);
+
+ return src->gfd.revents & src->gfd.events;
+}
+
+static gboolean
+vug_src_dispatch(GSource *gsrc, GSourceFunc cb, gpointer data)
+{
+ VugSrc *src = (VugSrc *)gsrc;
+
+ g_assert(src);
+
+ ((vu_watch_cb)cb)(src->dev, src->gfd.revents, data);
+
+ return G_SOURCE_CONTINUE;
+}
+
+static GSourceFuncs vug_src_funcs = {
+ vug_src_prepare,
+ vug_src_check,
+ vug_src_dispatch,
+ NULL
+};
+
+GSource *
+vug_source_new(VugDev *gdev, int fd, GIOCondition cond,
+ vu_watch_cb vu_cb, gpointer data)
+{
+ VuDev *dev = &gdev->parent;
+ GSource *gsrc;
+ VugSrc *src;
+ guint id;
+
+ g_assert(gdev);
+ g_assert(fd >= 0);
+ g_assert(vu_cb);
+
+ gsrc = g_source_new(&vug_src_funcs, sizeof(VugSrc));
+ g_source_set_callback(gsrc, (GSourceFunc)vu_cb, data, NULL);
+ src = (VugSrc *)gsrc;
+ src->dev = dev;
+ src->gfd.fd = fd;
+ src->gfd.events = cond;
+
+ g_source_add_poll(gsrc, &src->gfd);
+ id = g_source_attach(gsrc, g_main_context_get_thread_default());
+ g_assert(id);
+
+ return gsrc;
+}
+
+static void
+set_watch(VuDev *vu_dev, int fd, int vu_evt, vu_watch_cb cb, void *pvt)
+{
+ GSource *src;
+ VugDev *dev;
+
+ g_assert(vu_dev);
+ g_assert(fd >= 0);
+ g_assert(cb);
+
+ dev = container_of(vu_dev, VugDev, parent);
+ src = vug_source_new(dev, fd, vu_evt, cb, pvt);
+ g_hash_table_replace(dev->fdmap, GINT_TO_POINTER(fd), src);
+}
+
+static void
+remove_watch(VuDev *vu_dev, int fd)
+{
+ VugDev *dev;
+
+ g_assert(vu_dev);
+ g_assert(fd >= 0);
+
+ dev = container_of(vu_dev, VugDev, parent);
+ g_hash_table_remove(dev->fdmap, GINT_TO_POINTER(fd));
+}
+
+
+static void vug_watch(VuDev *dev, int condition, void *data)
+{
+ if (!vu_dispatch(dev) != 0) {
+ dev->panic(dev, "Error processing vhost message");
+ }
+}
+
+void vug_source_destroy(GSource *src)
+{
+ if (!src) {
+ return;
+ }
+
+ g_source_destroy(src);
+ g_source_unref(src);
+}
+
+bool
+vug_init(VugDev *dev, uint16_t max_queues, int socket,
+ vu_panic_cb panic, const VuDevIface *iface)
+{
+ g_assert(dev);
+ g_assert(iface);
+
+ if (!vu_init(&dev->parent, max_queues, socket, panic, NULL, set_watch,
+ remove_watch, iface)) {
+ return false;
+ }
+
+ dev->fdmap = g_hash_table_new_full(NULL, NULL, NULL,
+ (GDestroyNotify) vug_source_destroy);
+
+ dev->src = vug_source_new(dev, socket, G_IO_IN, vug_watch, NULL);
+
+ return true;
+}
+
+void
+vug_deinit(VugDev *dev)
+{
+ g_assert(dev);
+
+ g_hash_table_unref(dev->fdmap);
+ vug_source_destroy(dev->src);
+}
diff --git a/subprojects/libvhost-user/libvhost-user-glib.h b/subprojects/libvhost-user/libvhost-user-glib.h
new file mode 100644
index 0000000000..1a79a4916e
--- /dev/null
+++ b/subprojects/libvhost-user/libvhost-user-glib.h
@@ -0,0 +1,36 @@
+/*
+ * Vhost User library
+ *
+ * Copyright (c) 2016 Nutanix Inc. All rights reserved.
+ * Copyright (c) 2017 Red Hat, Inc.
+ *
+ * Authors:
+ * Marc-André Lureau <mlureau@redhat.com>
+ * Felipe Franciosi <felipe@nutanix.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.
+ */
+
+#ifndef LIBVHOST_USER_GLIB_H
+#define LIBVHOST_USER_GLIB_H
+
+#include <glib.h>
+#include "libvhost-user.h"
+
+typedef struct VugDev {
+ VuDev parent;
+
+ GHashTable *fdmap; /* fd -> gsource */
+ GSource *src;
+} VugDev;
+
+bool vug_init(VugDev *dev, uint16_t max_queues, int socket,
+ vu_panic_cb panic, const VuDevIface *iface);
+void vug_deinit(VugDev *dev);
+
+GSource *vug_source_new(VugDev *dev, int fd, GIOCondition cond,
+ vu_watch_cb vu_cb, gpointer data);
+void vug_source_destroy(GSource *src);
+
+#endif /* LIBVHOST_USER_GLIB_H */
diff --git a/subprojects/libvhost-user/libvhost-user.c b/subprojects/libvhost-user/libvhost-user.c
new file mode 100644
index 0000000000..fab7ca17ee
--- /dev/null
+++ b/subprojects/libvhost-user/libvhost-user.c
@@ -0,0 +1,2883 @@
+/*
+ * 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);
+}
diff --git a/subprojects/libvhost-user/libvhost-user.h b/subprojects/libvhost-user/libvhost-user.h
new file mode 100644
index 0000000000..7d47f1364a
--- /dev/null
+++ b/subprojects/libvhost-user/libvhost-user.h
@@ -0,0 +1,690 @@
+/*
+ * Vhost User library
+ *
+ * Copyright (c) 2016 Red Hat, Inc.
+ *
+ * Authors:
+ * Victor Kaplansky <victork@redhat.com>
+ * Marc-André Lureau <mlureau@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.
+ */
+
+#ifndef LIBVHOST_USER_H
+#define LIBVHOST_USER_H
+
+#include <stdint.h>
+#include <stdbool.h>
+#include <stddef.h>
+#include <sys/poll.h>
+#include <linux/vhost.h>
+#include <pthread.h>
+#include "standard-headers/linux/virtio_ring.h"
+
+/* Based on qemu/hw/virtio/vhost-user.c */
+#define VHOST_USER_F_PROTOCOL_FEATURES 30
+#define VHOST_LOG_PAGE 4096
+
+#define VIRTQUEUE_MAX_SIZE 1024
+
+#define VHOST_MEMORY_BASELINE_NREGIONS 8
+
+/*
+ * Set a reasonable maximum number of ram slots, which will be supported by
+ * any architecture.
+ */
+#define VHOST_USER_MAX_RAM_SLOTS 32
+
+#define VHOST_USER_HDR_SIZE offsetof(VhostUserMsg, payload.u64)
+
+typedef enum VhostSetConfigType {
+ VHOST_SET_CONFIG_TYPE_MASTER = 0,
+ VHOST_SET_CONFIG_TYPE_MIGRATION = 1,
+} VhostSetConfigType;
+
+/*
+ * Maximum size of virtio device config space
+ */
+#define VHOST_USER_MAX_CONFIG_SIZE 256
+
+enum VhostUserProtocolFeature {
+ VHOST_USER_PROTOCOL_F_MQ = 0,
+ VHOST_USER_PROTOCOL_F_LOG_SHMFD = 1,
+ VHOST_USER_PROTOCOL_F_RARP = 2,
+ VHOST_USER_PROTOCOL_F_REPLY_ACK = 3,
+ VHOST_USER_PROTOCOL_F_NET_MTU = 4,
+ VHOST_USER_PROTOCOL_F_SLAVE_REQ = 5,
+ VHOST_USER_PROTOCOL_F_CROSS_ENDIAN = 6,
+ VHOST_USER_PROTOCOL_F_CRYPTO_SESSION = 7,
+ VHOST_USER_PROTOCOL_F_PAGEFAULT = 8,
+ VHOST_USER_PROTOCOL_F_CONFIG = 9,
+ VHOST_USER_PROTOCOL_F_SLAVE_SEND_FD = 10,
+ VHOST_USER_PROTOCOL_F_HOST_NOTIFIER = 11,
+ VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD = 12,
+ VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS = 14,
+ VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS = 15,
+
+ VHOST_USER_PROTOCOL_F_MAX
+};
+
+#define VHOST_USER_PROTOCOL_FEATURE_MASK ((1 << VHOST_USER_PROTOCOL_F_MAX) - 1)
+
+typedef enum VhostUserRequest {
+ VHOST_USER_NONE = 0,
+ VHOST_USER_GET_FEATURES = 1,
+ VHOST_USER_SET_FEATURES = 2,
+ VHOST_USER_SET_OWNER = 3,
+ VHOST_USER_RESET_OWNER = 4,
+ VHOST_USER_SET_MEM_TABLE = 5,
+ VHOST_USER_SET_LOG_BASE = 6,
+ VHOST_USER_SET_LOG_FD = 7,
+ VHOST_USER_SET_VRING_NUM = 8,
+ VHOST_USER_SET_VRING_ADDR = 9,
+ VHOST_USER_SET_VRING_BASE = 10,
+ VHOST_USER_GET_VRING_BASE = 11,
+ VHOST_USER_SET_VRING_KICK = 12,
+ VHOST_USER_SET_VRING_CALL = 13,
+ VHOST_USER_SET_VRING_ERR = 14,
+ VHOST_USER_GET_PROTOCOL_FEATURES = 15,
+ VHOST_USER_SET_PROTOCOL_FEATURES = 16,
+ VHOST_USER_GET_QUEUE_NUM = 17,
+ VHOST_USER_SET_VRING_ENABLE = 18,
+ VHOST_USER_SEND_RARP = 19,
+ VHOST_USER_NET_SET_MTU = 20,
+ VHOST_USER_SET_SLAVE_REQ_FD = 21,
+ VHOST_USER_IOTLB_MSG = 22,
+ VHOST_USER_SET_VRING_ENDIAN = 23,
+ VHOST_USER_GET_CONFIG = 24,
+ VHOST_USER_SET_CONFIG = 25,
+ VHOST_USER_CREATE_CRYPTO_SESSION = 26,
+ VHOST_USER_CLOSE_CRYPTO_SESSION = 27,
+ VHOST_USER_POSTCOPY_ADVISE = 28,
+ VHOST_USER_POSTCOPY_LISTEN = 29,
+ VHOST_USER_POSTCOPY_END = 30,
+ VHOST_USER_GET_INFLIGHT_FD = 31,
+ VHOST_USER_SET_INFLIGHT_FD = 32,
+ VHOST_USER_GPU_SET_SOCKET = 33,
+ VHOST_USER_VRING_KICK = 35,
+ VHOST_USER_GET_MAX_MEM_SLOTS = 36,
+ VHOST_USER_ADD_MEM_REG = 37,
+ VHOST_USER_REM_MEM_REG = 38,
+ VHOST_USER_MAX
+} VhostUserRequest;
+
+typedef enum VhostUserSlaveRequest {
+ VHOST_USER_SLAVE_NONE = 0,
+ VHOST_USER_SLAVE_IOTLB_MSG = 1,
+ VHOST_USER_SLAVE_CONFIG_CHANGE_MSG = 2,
+ VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG = 3,
+ VHOST_USER_SLAVE_VRING_CALL = 4,
+ VHOST_USER_SLAVE_VRING_ERR = 5,
+ VHOST_USER_SLAVE_MAX
+} VhostUserSlaveRequest;
+
+typedef struct VhostUserMemoryRegion {
+ uint64_t guest_phys_addr;
+ uint64_t memory_size;
+ uint64_t userspace_addr;
+ uint64_t mmap_offset;
+} VhostUserMemoryRegion;
+
+typedef struct VhostUserMemory {
+ uint32_t nregions;
+ uint32_t padding;
+ VhostUserMemoryRegion regions[VHOST_MEMORY_BASELINE_NREGIONS];
+} VhostUserMemory;
+
+typedef struct VhostUserMemRegMsg {
+ uint64_t padding;
+ VhostUserMemoryRegion region;
+} VhostUserMemRegMsg;
+
+typedef struct VhostUserLog {
+ uint64_t mmap_size;
+ uint64_t mmap_offset;
+} VhostUserLog;
+
+typedef struct VhostUserConfig {
+ uint32_t offset;
+ uint32_t size;
+ uint32_t flags;
+ uint8_t region[VHOST_USER_MAX_CONFIG_SIZE];
+} VhostUserConfig;
+
+static VhostUserConfig c __attribute__ ((unused));
+#define VHOST_USER_CONFIG_HDR_SIZE (sizeof(c.offset) \
+ + sizeof(c.size) \
+ + sizeof(c.flags))
+
+typedef struct VhostUserVringArea {
+ uint64_t u64;
+ uint64_t size;
+ uint64_t offset;
+} VhostUserVringArea;
+
+typedef struct VhostUserInflight {
+ uint64_t mmap_size;
+ uint64_t mmap_offset;
+ uint16_t num_queues;
+ uint16_t queue_size;
+} VhostUserInflight;
+
+#if defined(_WIN32) && (defined(__x86_64__) || defined(__i386__))
+# define VU_PACKED __attribute__((gcc_struct, packed))
+#else
+# define VU_PACKED __attribute__((packed))
+#endif
+
+typedef struct VhostUserMsg {
+ int request;
+
+#define VHOST_USER_VERSION_MASK (0x3)
+#define VHOST_USER_REPLY_MASK (0x1 << 2)
+#define VHOST_USER_NEED_REPLY_MASK (0x1 << 3)
+ uint32_t flags;
+ uint32_t size; /* the following payload size */
+
+ union {
+#define VHOST_USER_VRING_IDX_MASK (0xff)
+#define VHOST_USER_VRING_NOFD_MASK (0x1 << 8)
+ uint64_t u64;
+ struct vhost_vring_state state;
+ struct vhost_vring_addr addr;
+ VhostUserMemory memory;
+ VhostUserMemRegMsg memreg;
+ VhostUserLog log;
+ VhostUserConfig config;
+ VhostUserVringArea area;
+ VhostUserInflight inflight;
+ } payload;
+
+ int fds[VHOST_MEMORY_BASELINE_NREGIONS];
+ int fd_num;
+ uint8_t *data;
+} VU_PACKED VhostUserMsg;
+
+typedef struct VuDevRegion {
+ /* Guest Physical address. */
+ uint64_t gpa;
+ /* Memory region size. */
+ uint64_t size;
+ /* QEMU virtual address (userspace). */
+ uint64_t qva;
+ /* Starting offset in our mmaped space. */
+ uint64_t mmap_offset;
+ /* Start address of mmaped space. */
+ uint64_t mmap_addr;
+} VuDevRegion;
+
+typedef struct VuDev VuDev;
+
+typedef uint64_t (*vu_get_features_cb) (VuDev *dev);
+typedef void (*vu_set_features_cb) (VuDev *dev, uint64_t features);
+typedef int (*vu_process_msg_cb) (VuDev *dev, VhostUserMsg *vmsg,
+ int *do_reply);
+typedef bool (*vu_read_msg_cb) (VuDev *dev, int sock, VhostUserMsg *vmsg);
+typedef void (*vu_queue_set_started_cb) (VuDev *dev, int qidx, bool started);
+typedef bool (*vu_queue_is_processed_in_order_cb) (VuDev *dev, int qidx);
+typedef int (*vu_get_config_cb) (VuDev *dev, uint8_t *config, uint32_t len);
+typedef int (*vu_set_config_cb) (VuDev *dev, const uint8_t *data,
+ uint32_t offset, uint32_t size,
+ uint32_t flags);
+
+typedef struct VuDevIface {
+ /* called by VHOST_USER_GET_FEATURES to get the features bitmask */
+ vu_get_features_cb get_features;
+ /* enable vhost implementation features */
+ vu_set_features_cb set_features;
+ /* get the protocol feature bitmask from the underlying vhost
+ * implementation */
+ vu_get_features_cb get_protocol_features;
+ /* enable protocol features in the underlying vhost implementation. */
+ vu_set_features_cb set_protocol_features;
+ /* process_msg is called for each vhost-user message received */
+ /* skip libvhost-user processing if return value != 0 */
+ vu_process_msg_cb process_msg;
+ /* tells when queues can be processed */
+ vu_queue_set_started_cb queue_set_started;
+ /*
+ * If the queue is processed in order, in which case it will be
+ * resumed to vring.used->idx. This can help to support resuming
+ * on unmanaged exit/crash.
+ */
+ vu_queue_is_processed_in_order_cb queue_is_processed_in_order;
+ /* get the config space of the device */
+ vu_get_config_cb get_config;
+ /* set the config space of the device */
+ vu_set_config_cb set_config;
+} VuDevIface;
+
+typedef void (*vu_queue_handler_cb) (VuDev *dev, int qidx);
+
+typedef struct VuRing {
+ unsigned int num;
+ struct vring_desc *desc;
+ struct vring_avail *avail;
+ struct vring_used *used;
+ uint64_t log_guest_addr;
+ uint32_t flags;
+} VuRing;
+
+typedef struct VuDescStateSplit {
+ /* Indicate whether this descriptor is inflight or not.
+ * Only available for head-descriptor. */
+ uint8_t inflight;
+
+ /* Padding */
+ uint8_t padding[5];
+
+ /* Maintain a list for the last batch of used descriptors.
+ * Only available when batching is used for submitting */
+ uint16_t next;
+
+ /* Used to preserve the order of fetching available descriptors.
+ * Only available for head-descriptor. */
+ uint64_t counter;
+} VuDescStateSplit;
+
+typedef struct VuVirtqInflight {
+ /* The feature flags of this region. Now it's initialized to 0. */
+ uint64_t features;
+
+ /* The version of this region. It's 1 currently.
+ * Zero value indicates a vm reset happened. */
+ uint16_t version;
+
+ /* The size of VuDescStateSplit array. It's equal to the virtqueue
+ * size. Slave could get it from queue size field of VhostUserInflight. */
+ uint16_t desc_num;
+
+ /* The head of list that track the last batch of used descriptors. */
+ uint16_t last_batch_head;
+
+ /* Storing the idx value of used ring */
+ uint16_t used_idx;
+
+ /* Used to track the state of each descriptor in descriptor table */
+ VuDescStateSplit desc[];
+} VuVirtqInflight;
+
+typedef struct VuVirtqInflightDesc {
+ uint16_t index;
+ uint64_t counter;
+} VuVirtqInflightDesc;
+
+typedef struct VuVirtq {
+ VuRing vring;
+
+ VuVirtqInflight *inflight;
+
+ VuVirtqInflightDesc *resubmit_list;
+
+ uint16_t resubmit_num;
+
+ uint64_t counter;
+
+ /* Next head to pop */
+ uint16_t last_avail_idx;
+
+ /* Last avail_idx read from VQ. */
+ uint16_t shadow_avail_idx;
+
+ uint16_t used_idx;
+
+ /* Last used index value we have signalled on */
+ uint16_t signalled_used;
+
+ /* Last used index value we have signalled on */
+ bool signalled_used_valid;
+
+ /* Notification enabled? */
+ bool notification;
+
+ int inuse;
+
+ vu_queue_handler_cb handler;
+
+ int call_fd;
+ int kick_fd;
+ int err_fd;
+ unsigned int enable;
+ bool started;
+
+ /* Guest addresses of our ring */
+ struct vhost_vring_addr vra;
+} VuVirtq;
+
+enum VuWatchCondtion {
+ VU_WATCH_IN = POLLIN,
+ VU_WATCH_OUT = POLLOUT,
+ VU_WATCH_PRI = POLLPRI,
+ VU_WATCH_ERR = POLLERR,
+ VU_WATCH_HUP = POLLHUP,
+};
+
+typedef void (*vu_panic_cb) (VuDev *dev, const char *err);
+typedef void (*vu_watch_cb) (VuDev *dev, int condition, void *data);
+typedef void (*vu_set_watch_cb) (VuDev *dev, int fd, int condition,
+ vu_watch_cb cb, void *data);
+typedef void (*vu_remove_watch_cb) (VuDev *dev, int fd);
+
+typedef struct VuDevInflightInfo {
+ int fd;
+ void *addr;
+ uint64_t size;
+} VuDevInflightInfo;
+
+struct VuDev {
+ int sock;
+ uint32_t nregions;
+ VuDevRegion regions[VHOST_USER_MAX_RAM_SLOTS];
+ VuVirtq *vq;
+ VuDevInflightInfo inflight_info;
+ int log_call_fd;
+ /* Must be held while using slave_fd */
+ pthread_mutex_t slave_mutex;
+ int slave_fd;
+ uint64_t log_size;
+ uint8_t *log_table;
+ uint64_t features;
+ uint64_t protocol_features;
+ bool broken;
+ uint16_t max_queues;
+
+ /*
+ * @read_msg: custom method to read vhost-user message
+ *
+ * Read data from vhost_user socket fd and fill up
+ * the passed VhostUserMsg *vmsg struct.
+ *
+ * If reading fails, it should close the received set of file
+ * descriptors as socket message's auxiliary data.
+ *
+ * For the details, please refer to vu_message_read in libvhost-user.c
+ * which will be used by default if not custom method is provided when
+ * calling vu_init
+ *
+ * Returns: true if vhost-user message successfully received,
+ * otherwise return false.
+ *
+ */
+ vu_read_msg_cb read_msg;
+
+ /*
+ * @set_watch: add or update the given fd to the watch set,
+ * call cb when condition is met.
+ */
+ vu_set_watch_cb set_watch;
+
+ /* @remove_watch: remove the given fd from the watch set */
+ vu_remove_watch_cb remove_watch;
+
+ /*
+ * @panic: encountered an unrecoverable error, you may try to re-initialize
+ */
+ vu_panic_cb panic;
+ const VuDevIface *iface;
+
+ /* Postcopy data */
+ int postcopy_ufd;
+ bool postcopy_listening;
+};
+
+typedef struct VuVirtqElement {
+ unsigned int index;
+ unsigned int out_num;
+ unsigned int in_num;
+ struct iovec *in_sg;
+ struct iovec *out_sg;
+} VuVirtqElement;
+
+/**
+ * vu_init:
+ * @dev: a VuDev context
+ * @max_queues: maximum number of virtqueues
+ * @socket: the socket connected to vhost-user master
+ * @panic: a panic callback
+ * @set_watch: a set_watch callback
+ * @remove_watch: a remove_watch callback
+ * @iface: a VuDevIface structure with vhost-user device callbacks
+ *
+ * Initializes a VuDev vhost-user context.
+ *
+ * Returns: true on success, false on failure.
+ **/
+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);
+
+
+/**
+ * vu_deinit:
+ * @dev: a VuDev context
+ *
+ * Cleans up the VuDev context
+ */
+void vu_deinit(VuDev *dev);
+
+/**
+ * vu_dispatch:
+ * @dev: a VuDev context
+ *
+ * Process one vhost-user message.
+ *
+ * Returns: TRUE on success, FALSE on failure.
+ */
+bool vu_dispatch(VuDev *dev);
+
+/**
+ * vu_gpa_to_va:
+ * @dev: a VuDev context
+ * @plen: guest memory size
+ * @guest_addr: guest address
+ *
+ * Translate a guest address to a pointer. Returns NULL on failure.
+ */
+void *vu_gpa_to_va(VuDev *dev, uint64_t *plen, uint64_t guest_addr);
+
+/**
+ * vu_get_queue:
+ * @dev: a VuDev context
+ * @qidx: queue index
+ *
+ * Returns the queue number @qidx.
+ */
+VuVirtq *vu_get_queue(VuDev *dev, int qidx);
+
+/**
+ * vu_set_queue_handler:
+ * @dev: a VuDev context
+ * @vq: a VuVirtq queue
+ * @handler: the queue handler callback
+ *
+ * Set the queue handler. This function may be called several times
+ * for the same queue. If called with NULL @handler, the handler is
+ * removed.
+ */
+void vu_set_queue_handler(VuDev *dev, VuVirtq *vq,
+ vu_queue_handler_cb handler);
+
+/**
+ * vu_set_queue_host_notifier:
+ * @dev: a VuDev context
+ * @vq: a VuVirtq queue
+ * @fd: a file descriptor
+ * @size: host page size
+ * @offset: notifier offset in @fd file
+ *
+ * Set queue's host notifier. This function may be called several
+ * times for the same queue. If called with -1 @fd, the notifier
+ * is removed.
+ */
+bool vu_set_queue_host_notifier(VuDev *dev, VuVirtq *vq, int fd,
+ int size, int offset);
+
+/**
+ * vu_queue_set_notification:
+ * @dev: a VuDev context
+ * @vq: a VuVirtq queue
+ * @enable: state
+ *
+ * Set whether the queue notifies (via event index or interrupt)
+ */
+void vu_queue_set_notification(VuDev *dev, VuVirtq *vq, int enable);
+
+/**
+ * vu_queue_enabled:
+ * @dev: a VuDev context
+ * @vq: a VuVirtq queue
+ *
+ * Returns: whether the queue is enabled.
+ */
+bool vu_queue_enabled(VuDev *dev, VuVirtq *vq);
+
+/**
+ * vu_queue_started:
+ * @dev: a VuDev context
+ * @vq: a VuVirtq queue
+ *
+ * Returns: whether the queue is started.
+ */
+bool vu_queue_started(const VuDev *dev, const VuVirtq *vq);
+
+/**
+ * vu_queue_empty:
+ * @dev: a VuDev context
+ * @vq: a VuVirtq queue
+ *
+ * Returns: true if the queue is empty or not ready.
+ */
+bool vu_queue_empty(VuDev *dev, VuVirtq *vq);
+
+/**
+ * vu_queue_notify:
+ * @dev: a VuDev context
+ * @vq: a VuVirtq queue
+ *
+ * Request to notify the queue via callfd (skipped if unnecessary)
+ */
+void vu_queue_notify(VuDev *dev, VuVirtq *vq);
+
+/**
+ * vu_queue_notify_sync:
+ * @dev: a VuDev context
+ * @vq: a VuVirtq queue
+ *
+ * Request to notify the queue via callfd (skipped if unnecessary)
+ * or sync message if possible.
+ */
+void vu_queue_notify_sync(VuDev *dev, VuVirtq *vq);
+
+/**
+ * vu_queue_pop:
+ * @dev: a VuDev context
+ * @vq: a VuVirtq queue
+ * @sz: the size of struct to return (must be >= VuVirtqElement)
+ *
+ * Returns: a VuVirtqElement filled from the queue or NULL. The
+ * returned element must be free()-d by the caller.
+ */
+void *vu_queue_pop(VuDev *dev, VuVirtq *vq, size_t sz);
+
+
+/**
+ * vu_queue_unpop:
+ * @dev: a VuDev context
+ * @vq: a VuVirtq queue
+ * @elem: The #VuVirtqElement
+ * @len: number of bytes written
+ *
+ * Pretend the most recent element wasn't popped from the virtqueue. The next
+ * call to vu_queue_pop() will refetch the element.
+ */
+void vu_queue_unpop(VuDev *dev, VuVirtq *vq, VuVirtqElement *elem,
+ size_t len);
+
+/**
+ * vu_queue_rewind:
+ * @dev: a VuDev context
+ * @vq: a VuVirtq queue
+ * @num: number of elements to push back
+ *
+ * Pretend that elements weren't popped from the virtqueue. The next
+ * virtqueue_pop() will refetch the oldest element.
+ *
+ * Returns: true on success, false if @num is greater than the number of in use
+ * elements.
+ */
+bool vu_queue_rewind(VuDev *dev, VuVirtq *vq, unsigned int num);
+
+/**
+ * vu_queue_fill:
+ * @dev: a VuDev context
+ * @vq: a VuVirtq queue
+ * @elem: a VuVirtqElement
+ * @len: length in bytes to write
+ * @idx: optional offset for the used ring index (0 in general)
+ *
+ * Fill the used ring with @elem element.
+ */
+void vu_queue_fill(VuDev *dev, VuVirtq *vq,
+ const VuVirtqElement *elem,
+ unsigned int len, unsigned int idx);
+
+/**
+ * vu_queue_push:
+ * @dev: a VuDev context
+ * @vq: a VuVirtq queue
+ * @elem: a VuVirtqElement
+ * @len: length in bytes to write
+ *
+ * Helper that combines vu_queue_fill() with a vu_queue_flush().
+ */
+void vu_queue_push(VuDev *dev, VuVirtq *vq,
+ const VuVirtqElement *elem, unsigned int len);
+
+/**
+ * vu_queue_flush:
+ * @dev: a VuDev context
+ * @vq: a VuVirtq queue
+ * @num: number of elements to flush
+ *
+ * Mark the last number of elements as done (used.idx is updated by
+ * num elements).
+*/
+void vu_queue_flush(VuDev *dev, VuVirtq *vq, unsigned int num);
+
+/**
+ * vu_queue_get_avail_bytes:
+ * @dev: a VuDev context
+ * @vq: a VuVirtq queue
+ * @in_bytes: in bytes
+ * @out_bytes: out bytes
+ * @max_in_bytes: stop counting after max_in_bytes
+ * @max_out_bytes: stop counting after max_out_bytes
+ *
+ * Count the number of available bytes, up to max_in_bytes/max_out_bytes.
+ */
+void vu_queue_get_avail_bytes(VuDev *vdev, VuVirtq *vq, unsigned int *in_bytes,
+ unsigned int *out_bytes,
+ unsigned max_in_bytes, unsigned max_out_bytes);
+
+/**
+ * vu_queue_avail_bytes:
+ * @dev: a VuDev context
+ * @vq: a VuVirtq queue
+ * @in_bytes: expected in bytes
+ * @out_bytes: expected out bytes
+ *
+ * Returns: true if in_bytes <= in_total && out_bytes <= out_total
+ */
+bool vu_queue_avail_bytes(VuDev *dev, VuVirtq *vq, unsigned int in_bytes,
+ unsigned int out_bytes);
+
+#endif /* LIBVHOST_USER_H */
diff --git a/subprojects/libvhost-user/meson.build b/subprojects/libvhost-user/meson.build
new file mode 100644
index 0000000000..f9ecc534cf
--- /dev/null
+++ b/subprojects/libvhost-user/meson.build
@@ -0,0 +1,20 @@
+project('libvhost-user', 'c',
+ license: 'GPL-2.0-or-later',
+ default_options: ['c_std=gnu99'])
+
+glib = dependency('glib-2.0')
+inc = include_directories('../../include', '../../linux-headers')
+
+vhost_user = static_library('vhost-user',
+ files('libvhost-user.c'),
+ include_directories: inc,
+ c_args: '-D_GNU_SOURCE')
+
+vhost_user_glib = static_library('vhost-user-glib',
+ files('libvhost-user-glib.c'),
+ include_directories: inc,
+ link_with: vhost_user,
+ dependencies: glib)
+
+vhost_user_dep = declare_dependency(link_with: vhost_user_glib,
+ include_directories: include_directories('.'))