From: Marc-André Lureau <marcandre.lur...@redhat.com>
Add a library to help implementing vhost-user backend (or slave).
Dealing with vhost-user as an application developper isn't so easy: you
have all the trouble with any protocol: validation, unix ancillary data,
shared memory, eventfd, logging, and on top of that you need to deal
with virtio queues, if possible efficiently.
qemu test has a nice vhost-user testing application vhost-user-bridge,
which implements most of vhost-user, and virtio.c which implements
virtqueues manipulation. Based on these two, I tried to make a simple
library, reusable for tests or development of new vhost-user scenarios.
Signed-off-by: Marc-André Lureau <marcandre.lur...@redhat.com>
---
Makefile | 1 +
Makefile.objs | 1 +
contrib/libvhost-user/Makefile.objs | 1 +
contrib/libvhost-user/libvhost-user.c | 1429 +++++++++++++++++++++++++++++++++
contrib/libvhost-user/libvhost-user.h | 270 +++++++
5 files changed, 1702 insertions(+)
create mode 100644 contrib/libvhost-user/Makefile.objs
create mode 100644 contrib/libvhost-user/libvhost-user.c
create mode 100644 contrib/libvhost-user/libvhost-user.h
diff --git a/Makefile b/Makefile
index b8563db..251217c 100644
--- a/Makefile
+++ b/Makefile
@@ -151,6 +151,7 @@ dummy := $(call unnest-vars,, \
qga-obj-y \
ivshmem-client-obj-y \
ivshmem-server-obj-y \
+ libvhost-user-obj-y \
qga-vss-dll-obj-y \
block-obj-y \
block-obj-m \
diff --git a/Makefile.objs b/Makefile.objs
index da49b71..5812da7 100644
--- a/Makefile.objs
+++ b/Makefile.objs
@@ -115,3 +115,4 @@ qga-vss-dll-obj-y = qga/
# contrib
ivshmem-client-obj-y = contrib/ivshmem-client/
ivshmem-server-obj-y = contrib/ivshmem-server/
+libvhost-user-obj-y = contrib/libvhost-user/
diff --git a/contrib/libvhost-user/Makefile.objs
b/contrib/libvhost-user/Makefile.objs
new file mode 100644
index 0000000..cef1ad6
--- /dev/null
+++ b/contrib/libvhost-user/Makefile.objs
@@ -0,0 +1 @@
+libvhost-user-obj-y = libvhost-user.o
diff --git a/contrib/libvhost-user/libvhost-user.c
b/contrib/libvhost-user/libvhost-user.c
new file mode 100644
index 0000000..a5b1557
--- /dev/null
+++ b/contrib/libvhost-user/libvhost-user.c
@@ -0,0 +1,1429 @@
+/*
+ * Vhost User library
+ *
+ * Copyright IBM, Corp. 2007
+ * Copyright (c) 2016 Red Hat, Inc.
+ *
+ * Authors:
+ * Anthony Liguori <aligu...@us.ibm.com>
+ * Marc-André Lureau <mlur...@redhat.com>
+ * Victor Kaplansky <vict...@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.
+ */
+
+#include <qemu/osdep.h>
+#include <sys/eventfd.h>
+#include <linux/vhost.h>
+
+#include "qemu/atomic.h"
+
+#include "libvhost-user.h"
+
+#define VHOST_USER_HDR_SIZE offsetof(VhostUserMsg, payload.u64)
+
+/* 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 const char *
+vu_request_to_string(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_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_INPUT_GET_CONFIG),
+ 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;
+ int unused __attribute__ ((unused));
+ va_list ap;
+
+ va_start(ap, msg);
+ unused = vasprintf(&buf, msg, ap);
+ va_end(ap);
+
+ dev->panic(dev, buf);
+ free(buf);
+}
+
+/* Translate guest physical address to our virtual address. */
+void *
+vu_gpa_to_va(VuDev *dev, uint64_t guest_addr)
+{
+ int i;
+
+ /* 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))) {
+ 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]);
+ }
+}
+
+static bool
+vu_message_read(VuDev *dev, int conn_fd, VhostUserMsg *vmsg)
+{
+ char control[CMSG_SPACE(VHOST_MEMORY_MAX_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;
+
+ /* 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;
+
+ do {
+ rc = write(conn_fd, p, VHOST_USER_HDR_SIZE);
+ } while (rc < 0 && (errno == EINTR || errno == EAGAIN));
+
+ 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;
+}
+
+/* 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);
+ atomic_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 += VHOST_LOG_PAGE;
+ }
+
+ 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 =
+ 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);
+
+ 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)
+{
+ int i;
+
+ for (i = 0; i < VHOST_MAX_NR_VIRTQUEUE; 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 (!(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
+vu_set_mem_table_exec(VuDev *dev, VhostUserMsg *vmsg)
+{
+ int i;
+ VhostUserMemory *memory = &vmsg->payload.memory;
+ dev->nregions = memory->nregions;
+
+ DPRINT("Nregions: %d\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]);
+ }
+
+ 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);
+ if (rc == MAP_FAILED) {
+ perror("log mmap error");
+ }
+ dev->log_table = rc;
+ dev->log_size = log_mmap_size;
+
+ vmsg->size = sizeof(vmsg->payload.u64);
+
+ 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: %d\n", index);
+ DPRINT("State.num: %d\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 *vra = &vmsg->payload.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%016llx\n", vra->desc_user_addr);
+ DPRINT(" used_user_addr: 0x%016llx\n", vra->used_user_addr);
+ DPRINT(" avail_user_addr: 0x%016llx\n", vra->avail_user_addr);
+ DPRINT(" log_guest_addr: 0x%016llx\n", vra->log_guest_addr);
+
+ vq->vring.flags = vra->flags;
+ vq->vring.desc = qva_to_va(dev, vra->desc_user_addr);
+ vq->vring.used = qva_to_va(dev, vra->used_user_addr);
+ vq->vring.avail = qva_to_va(dev, vra->avail_user_addr);
+ vq->vring.log_guest_addr = vra->log_guest_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);
+
+ if (!(vq->vring.desc && vq->vring.used && vq->vring.avail)) {
+ vu_panic(dev, "Invalid vring_addr message");
+ return false;
+ }
+
+ 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: %d\n", index);
+ DPRINT("State.num: %d\n", num);
+ 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: %d\n", index);
+ vmsg->payload.state.num = dev->vq[index].last_avail_idx;
+ vmsg->size = sizeof(vmsg->payload.state);
+
+ if (dev->iface->queue_set_started) {
+ dev->vq[index].started = false;
+ 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;
+
+ if (index >= VHOST_MAX_NR_VIRTQUEUE) {
+ vmsg_close_fds(vmsg);
+ vu_panic(dev, "Invalid queue index: %u", index);
+ return false;
+ }
+
+ if (vmsg->payload.u64 & VHOST_USER_VRING_NOFD_MASK ||
+ vmsg->fd_num != 1) {
+ vmsg_close_fds(vmsg);
+ vu_panic(dev, "Invalid fds in request: %d", vmsg->request);
+ return false;
+ }
+
+ return true;
+}
+
+static bool
+vu_set_vring_kick_exec(VuDev *dev, VhostUserMsg *vmsg)
+{
+ int index = vmsg->payload.u64 & VHOST_USER_VRING_IDX_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;
+ }
+
+ if (!(vmsg->payload.u64 & VHOST_USER_VRING_NOFD_MASK)) {
+ dev->vq[index].kick_fd = vmsg->fds[0];
+ DPRINT("Got kick_fd: %d for vq: %d\n", vmsg->fds[0], index);
+ }
+
+ if (dev->iface->queue_set_started) {
+ dev->vq[index].started = true;
+ dev->iface->queue_set_started(dev, index, true);
+ }
+
+ if (dev->vq[index].kick_fd != -1 && dev->vq[index].handler) {
+ dev->add_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);
+ }
+
+ 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->add_watch(dev, vq->kick_fd, VU_WATCH_IN,
+ vu_kick_cb, (void *)(long)qidx);
+ } else {
+ dev->remove_watch(dev, vq->kick_fd);
+ }
+ }
+}
+
+static bool
+vu_set_vring_call_exec(VuDev *dev, VhostUserMsg *vmsg)
+{
+ int index = vmsg->payload.u64 & VHOST_USER_VRING_IDX_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;
+ }
+
+ if (!(vmsg->payload.u64 & VHOST_USER_VRING_NOFD_MASK)) {
+ dev->vq[index].call_fd = vmsg->fds[0];
+ }
+
+ DPRINT("Got call_fd: %d for vq: %d\n", vmsg->fds[0], index);
+
+ return false;
+}
+
+static bool
+vu_set_vring_err_exec(VuDev *dev, VhostUserMsg *vmsg)
+{
+ int index = vmsg->payload.u64 & VHOST_USER_VRING_IDX_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;
+ }
+
+ if (!(vmsg->payload.u64 & VHOST_USER_VRING_NOFD_MASK)) {
+ dev->vq[index].err_fd = vmsg->fds[0];
+ }
+
+ return false;
+}
+
+static bool
+vu_get_protocol_features_exec(VuDev *dev, VhostUserMsg *vmsg)
+{
+ uint64_t features = 1ULL << VHOST_USER_PROTOCOL_F_LOG_SHMFD;
+
+ if (dev->iface->get_protocol_features) {
+ features |= dev->iface->get_protocol_features(dev);
+ }
+
+ vmsg->payload.u64 = features;
+ vmsg->size = sizeof(vmsg->payload.u64);
+
+ 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 (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)
+{
+ DPRINT("Function %s() not implemented yet.\n", __func__);
+ return false;
+}
+
+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: %d\n", index);
+ DPRINT("State.enable: %d\n", enable);
+
+ if (index >= VHOST_MAX_NR_VIRTQUEUE) {
+ vu_panic(dev, "Invalid vring_enable index: %u", index);
+ return false;
+ }
+
+ dev->vq[index].enable = enable;
+ 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: %d\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);
+ 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 success = false;
+
+ if (!vu_message_read(dev, dev->sock, &vmsg)) {
+ goto end;
+ }
+
+ reply_requested = vu_process_message(dev, &vmsg);
+ if (!reply_requested) {
+ success = true;
+ goto end;
+ }
+
+ if (!vu_message_write(dev, dev->sock, &vmsg)) {
+ goto end;
+ }
+
+ success = true;
+
+end:
+ g_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 < VHOST_MAX_NR_VIRTQUEUE; i++) {
+ VuVirtq *vq = &dev->vq[i];
+
+ if (vq->call_fd != -1) {
+ close(vq->call_fd);
+ vq->call_fd = -1;
+ }
+
+ if (vq->kick_fd != -1) {
+ close(vq->kick_fd);
+ vq->kick_fd = -1;
+ }
+
+ if (vq->err_fd != -1) {
+ close(vq->err_fd);
+ vq->err_fd = -1;
+ }
+ }
+
+
+ vu_close_log(dev);
+
+ if (dev->sock != -1) {
+ close(dev->sock);
+ }
+}
+
+void
+vu_init(VuDev *dev,
+ int socket,
+ vu_panic_cb panic,
+ vu_add_watch_cb add_watch,
+ vu_remove_watch_cb remove_watch,
+ const VuDevIface *iface)
+{
+ int i;
+
+ assert(socket >= 0);
+ assert(add_watch);
+ assert(remove_watch);
+ assert(iface);
+ assert(panic);
+
+ memset(dev, 0, sizeof(*dev));
+
+ dev->sock = socket;
+ dev->panic = panic;
+ dev->add_watch = add_watch;
+ dev->remove_watch = remove_watch;
+ dev->iface = iface;
+ dev->log_call_fd = -1;
+ for (i = 0; i < VHOST_MAX_NR_VIRTQUEUE; i++) {
+ dev->vq[i] = (VuVirtq) {
+ .call_fd = -1, .kick_fd = -1, .err_fd = -1,
+ .notification = true,
+ };
+ }
+}
+
+VuVirtq *
+vu_get_queue(VuDev *dev, int qidx)
+{
+ return &dev->vq[qidx];
+}
+
+bool
+vu_queue_enabled(VuDev *dev, VuVirtq *vq)
+{
+ return vq->enable;
+}
+
+static inline uint16_t
+vring_avail_flags(VuVirtq *vq)
+{
+ return vq->vring.avail->flags;
+}
+
+static inline uint16_t
+vring_avail_idx(VuVirtq *vq)
+{
+ vq->shadow_avail_idx = vq->vring.avail->idx;
+
+ return vq->shadow_avail_idx;
+}
+
+static inline uint16_t
+vring_avail_ring(VuVirtq *vq, int i)
+{
+ return 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 0;
+ }
+ 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 unsigned int
+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 0;
+ }
+
+ return head;
+}
+
+static unsigned
+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 (!(desc[i].flags & VRING_DESC_F_NEXT)) {
+ return max;
+ }
+
+ /* Check they're not leading us off end of descriptors. */
+ next = 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 0;
+ }
+
+ return next;
+}
+
+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;
+
+ idx = vq->last_avail_idx;
+
+ total_bufs = in_total = out_total = 0;
+ while (virtqueue_num_heads(dev, vq, idx)) {
+ unsigned int max, num_bufs, indirect = 0;
+ struct vring_desc *desc;
+ int i;
+
+ max = vq->vring.num;
+ num_bufs = total_bufs;
+ i = virtqueue_get_head(dev, vq, idx++);
+ desc = vq->vring.desc;
+
+ if (desc[i].flags & VRING_DESC_F_INDIRECT) {
+ if (desc[i].len % sizeof(struct vring_desc)) {
+ vu_panic(dev, "Invalid size for indirect buffer table");
+ }
+
+ /* If we've got too many, that implies a descriptor loop. */
+ if (num_bufs >= max) {
+ vu_panic(dev, "Looped descriptor");
+ }
+
+ /* loop over the indirect descriptor table */
+ indirect = 1;
+ max = desc[i].len / sizeof(struct vring_desc);
+ desc = vu_gpa_to_va(dev, desc[i].addr);
+ 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");
+ }
+
+ if (desc[i].flags & VRING_DESC_F_WRITE) {
+ in_total += desc[i].len;
+ } else {
+ out_total += desc[i].len;
+ }
+ if (in_total >= max_in_bytes && out_total >= max_out_bytes) {
+ goto done;
+ }
+ } while ((i = virtqueue_read_next_desc(dev, desc, i, max)) != max);
+
+ if (!indirect) {
+ total_bufs = num_bufs;
+ } else {
+ total_bufs++;
+ }
+ }
+done:
+ if (in_bytes) {
+ *in_bytes = in_total;
+ }
+ if (out_bytes) {
+ *out_bytes = out_total;
+ }
+}
+
+int
+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. */
+int
+vu_queue_empty(VuDev *dev, VuVirtq *vq)
+{
+ if (vq->shadow_avail_idx != vq->last_avail_idx) {
+ return 0;
+ }
+
+ return vring_avail_idx(vq) == vq->last_avail_idx;
+}
+
+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 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);
+}
+
+void
+vu_queue_notify(VuDev *dev, VuVirtq *vq)
+{
+ if (!vring_notify(dev, vq)) {
+ DPRINT("skipped notify...\n");
+ return;
+ }
+
+ if (eventfd_write(vq->call_fd, 1) < 0) {
+ vu_panic(dev, "Error writing eventfd: %s", strerror(errno));
+ }
+}
+
+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 |= 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 &= ~mask;
+}
+
+static inline void
+vring_set_avail_event(VuVirtq *vq, uint16_t val)
+{
+ if (!vq->notification) {
+ return;
+ }
+
+ *((uint16_t *) &vq->vring.used->ring[vq->vring.num]) = 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 void
+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);
+
+ iov[num_sg].iov_base = vu_gpa_to_va(dev, pa);
+ iov[num_sg].iov_len = sz;
+ num_sg++;
+
+ *p_num_sg = num_sg;
+}
+
+/* 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))
+
+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;
+}
+
+void *
+vu_queue_pop(VuDev *dev, VuVirtq *vq, size_t sz)
+{
+ unsigned int i, head, max;
+ VuVirtqElement *elem;
+ unsigned out_num, in_num;
+ struct iovec iov[VIRTQUEUE_MAX_SIZE];
+ struct vring_desc *desc;
+
+ if (vu_queue_empty(dev, vq)) {
+ return NULL;
+ }
+ /* Needed after virtio_queue_empty(), see comment in
+ * virtqueue_num_heads(). */
+ smp_rmb();
+
+ /* When we start there are none of either input nor output. */
+ out_num = in_num = 0;
+
+ max = vq->vring.num;
+
+ i = head = virtqueue_get_head(dev, vq, vq->last_avail_idx++);
+ if (vu_has_feature(dev, VIRTIO_RING_F_EVENT_IDX)) {
+ vring_set_avail_event(vq, vq->last_avail_idx);
+ }
+
+ desc = vq->vring.desc;
+ if (desc[i].flags & VRING_DESC_F_INDIRECT) {
+ if (desc[i].len % sizeof(struct vring_desc)) {
+ vu_panic(dev, "Invalid size for indirect buffer table");
+ }
+
+ /* loop over the indirect descriptor table */
+ max = desc[i].len / sizeof(struct vring_desc);
+ desc = vu_gpa_to_va(dev, desc[i].addr);
+ i = 0;
+ }
+
+ /* Collect all the descriptors */
+ do {
+ if (desc[i].flags & VRING_DESC_F_WRITE) {
+ virtqueue_map_desc(dev, &in_num, iov + out_num,
+ VIRTQUEUE_MAX_SIZE - out_num, true,
+ desc[i].addr, desc[i].len);
+ } else {
+ if (in_num) {
+ vu_panic(dev, "Incorrect order for descriptors");
+ }
+ virtqueue_map_desc(dev, &out_num, iov,
+ VIRTQUEUE_MAX_SIZE, false,
+ desc[i].addr, desc[i].len);
+ }
+
+ /* If we've got too many, that implies a descriptor loop. */
+ if ((in_num + out_num) > max) {
+ vu_panic(dev, "Looped descriptor");
+ }
+ } while ((i = virtqueue_read_next_desc(dev, desc, i, max)) != max);
+
+ /* Now copy what we have collected and mapped */
+ elem = virtqueue_alloc_element(sz, out_num, in_num);
+ elem->index = head;
+ 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];
+ }
+
+ vq->inuse++;
+
+ return elem;
+}
+
+void
+vu_queue_discard(VuDev *dev, VuVirtq *vq)
+{
+ vq->last_avail_idx--;
+}
+
+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;
+ unsigned num_bufs = 0;
+
+ max = vq->vring.num;
+ i = elem->index;
+
+ if (desc[i].flags & VRING_DESC_F_INDIRECT) {
+ if (desc[i].len % sizeof(struct vring_desc)) {
+ vu_panic(dev, "Invalid size for indirect buffer table");
+ }
+
+ /* loop over the indirect descriptor table */
+ max = desc[i].len / sizeof(struct vring_desc);
+ desc = vu_gpa_to_va(dev, desc[i].addr);
+ i = 0;
+ }
+
+ do {
+ if (++num_bufs > max) {
+ vu_panic(dev, "Looped descriptor");
+ return;
+ }
+
+ if (desc[i].flags & VRING_DESC_F_WRITE) {
+ min = MIN(desc[i].len, len);
+ vu_log_write(dev, desc[i].addr, min);
+ len -= min;
+ }
+
+ } while (len > 0 &&
+ (i = virtqueue_read_next_desc(dev, desc, i, max)) != max);
+}
+
+void
+vu_queue_fill(VuDev *dev, VuVirtq *vq,
+ const VuVirtqElement *elem,
+ unsigned int len, unsigned int idx)
+{
+ struct vring_used_elem uelem;
+
+ vu_log_queue_fill(dev, vq, elem, len);
+
+ idx = (idx + vq->used_idx) % vq->vring.num;
+
+ uelem.id = elem->index;
+ uelem.len = 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 = 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;
+ /* 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_flush(dev, vq, 1);
+}
diff --git a/contrib/libvhost-user/libvhost-user.h
b/contrib/libvhost-user/libvhost-user.h
new file mode 100644
index 0000000..9733b1a
--- /dev/null
+++ b/contrib/libvhost-user/libvhost-user.h
@@ -0,0 +1,270 @@
+/*
+ * Vhost User library
+ *
+ * Copyright (c) 2016 Red Hat, Inc.
+ *
+ * Authors:
+ * Victor Kaplansky <vict...@redhat.com>
+ * Marc-André Lureau <mlur...@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 <linux/vhost.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 VHOST_MAX_NR_VIRTQUEUE 8
+#define VIRTQUEUE_MAX_SIZE 1024
+
+#define VHOST_MEMORY_MAX_NREGIONS 8
+
+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_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_INPUT_GET_CONFIG = 20,
+ VHOST_USER_MAX
+} VhostUserRequest;
+
+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_MAX_NREGIONS];
+} VhostUserMemory;
+
+typedef struct VhostUserLog {
+ uint64_t mmap_size;
+ uint64_t mmap_offset;
+} VhostUserLog;
+
+#if defined(_WIN32)
+# define VU_PACKED __attribute__((gcc_struct, packed))
+#else
+# define VU_PACKED __attribute__((packed))
+#endif
+
+typedef struct VhostUserMsg {
+ VhostUserRequest request;
+
+#define VHOST_USER_VERSION_MASK (0x3)
+#define VHOST_USER_REPLY_MASK (0x1 << 2)
+ 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;
+ VhostUserLog log;
+ } payload;
+
+ int fds[VHOST_MEMORY_MAX_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 void (*vu_queue_set_started_cb) (VuDev *dev, int qidx, bool started);
+
+typedef struct VuDevIface {
+ vu_get_features_cb get_features;
+ vu_set_features_cb set_features;
+ vu_get_features_cb get_protocol_features;
+ vu_set_features_cb set_protocol_features;
+ vu_process_msg_cb process_msg;
+ vu_queue_set_started_cb queue_set_started;
+} 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 VuVirtq {
+ VuRing vring;
+
+ /* 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;
+} VuVirtq;
+
+enum VuWatchCondtion {
+ VU_WATCH_IN = 1 << 0,
+ VU_WATCH_OUT = 1 << 1,
+ VU_WATCH_PRI = 1 << 2,
+ VU_WATCH_ERR = 1 << 3,
+ VU_WATCH_HUP = 1 << 4,
+};
+
+typedef void (*vu_panic_cb) (VuDev *dev, const char *err);
+typedef void (*vu_watch_cb) (VuDev *dev, int condition, void *data);
+typedef void (*vu_add_watch_cb) (VuDev *dev, int fd, int condition,
+ vu_watch_cb cb, void *data);
+typedef void (*vu_remove_watch_cb) (VuDev *dev, int fd);
+
+struct VuDev {
+ int sock;
+ uint32_t nregions;
+ VuDevRegion regions[VHOST_MEMORY_MAX_NREGIONS];
+ VuVirtq vq[VHOST_MAX_NR_VIRTQUEUE];
+ int log_call_fd;
+ uint64_t log_size;
+ uint8_t *log_table;
+ uint64_t features;
+ uint64_t protocol_features;
+
+ vu_add_watch_cb add_watch;
+ vu_remove_watch_cb remove_watch;
+ vu_panic_cb panic;
+ const VuDevIface *iface;
+};
+
+typedef struct VuVirtqElement {
+ unsigned int index;
+ unsigned int out_num;
+ unsigned int in_num;
+ struct iovec *in_sg;
+ struct iovec *out_sg;
+} VuVirtqElement;
+
+void vu_init(VuDev *dev,
+ int socket,
+ vu_panic_cb panic,
+ vu_add_watch_cb add_watch,
+ vu_remove_watch_cb remove_watch,
+ const VuDevIface *iface);
+
+void vu_deinit(VuDev *dev);
+
+bool vu_dispatch(VuDev *dev);
+
+void *vu_gpa_to_va(VuDev *dev, uint64_t guest_addr);
+
+VuVirtq *vu_get_queue(VuDev *dev, int qidx);
+
+void vu_set_queue_handler(VuDev *dev, VuVirtq *vq,
+ vu_queue_handler_cb handler);
+
+void vu_queue_set_notification(VuDev *dev, VuVirtq *vq, int enable);
+
+bool vu_queue_enabled(VuDev *dev, VuVirtq *vq);
+
+int vu_queue_empty(VuDev *dev, VuVirtq *vq);
+
+void vu_queue_notify(VuDev *dev, VuVirtq *vq);
+
+void *vu_queue_pop(VuDev *dev, VuVirtq *vq, size_t sz);
+void vu_queue_discard(VuDev *dev, VuVirtq *vq);
+
+void vu_queue_fill(VuDev *dev, VuVirtq *vq,
+ const VuVirtqElement *elem,
+ unsigned int len, unsigned int idx);
+
+void vu_queue_push(VuDev *dev, VuVirtq *vq,
+ const VuVirtqElement *elem, unsigned int len);
+
+void vu_queue_flush(VuDev *dev, VuVirtq *vq, unsigned int count);
+
+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);
+
+int vu_queue_avail_bytes(VuDev *dev, VuVirtq *vq, unsigned int in_bytes,
+ unsigned int out_bytes);
+
+#endif /* LIBVHOST_USER_H */
--
2.7.4
