@@ -53,6 +53,7 @@
/scsi/qemu-pr-helper
/vscclient
/vhost-user-scsi
+/vhost-user-blk
/fsdev/virtfs-proxy-helper
*.tmp
*.[1-9]
@@ -318,6 +318,7 @@ dummy := $(call unnest-vars,, \
ivshmem-server-obj-y \
libvhost-user-obj-y \
vhost-user-scsi-obj-y \
+ vhost-user-blk-obj-y \
qga-vss-dll-obj-y \
block-obj-y \
block-obj-m \
@@ -534,6 +535,8 @@ ivshmem-server$(EXESUF): $(ivshmem-server-obj-y) $(COMMON_LDADDS)
endif
vhost-user-scsi$(EXESUF): $(vhost-user-scsi-obj-y) libvhost-user.a
$(call LINK, $^)
+vhost-user-blk$(EXESUF): $(vhost-user-blk-obj-y) libvhost-user.a
+ $(call LINK, $^)
module_block.h: $(SRC_PATH)/scripts/modules/module_block.py config-host.mak
$(call quiet-command,$(PYTHON) $< $@ \
@@ -115,6 +115,7 @@ libvhost-user-obj-y = contrib/libvhost-user/
vhost-user-scsi.o-cflags := $(LIBISCSI_CFLAGS)
vhost-user-scsi.o-libs := $(LIBISCSI_LIBS)
vhost-user-scsi-obj-y = contrib/vhost-user-scsi/
+vhost-user-blk-obj-y = contrib/vhost-user-blk/
######################################################################
trace-events-subdirs =
new file mode 100644
@@ -0,0 +1 @@
+vhost-user-blk-obj-y = vhost-user-blk.o
new file mode 100644
@@ -0,0 +1,492 @@
+/*
+ * vhost-user-blk sample application
+ *
+ * Copyright IBM, Corp. 2007
+ * Copyright (c) 2016 Nutanix Inc. All rights reserved.
+ * Copyright (c) 2017 Intel Corporation. All rights reserved.
+ *
+ * Author:
+ * Anthony Liguori <aliguori@us.ibm.com>
+ * Felipe Franciosi <felipe@nutanix.com>
+ * Changpeng Liu <changpeng.liu@intel.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 only.
+ * See the COPYING file in the top-level directory.
+ */
+
+#include "qemu/osdep.h"
+#include "standard-headers/linux/virtio_blk.h"
+#include "contrib/libvhost-user/libvhost-user-glib.h"
+#include "contrib/libvhost-user/libvhost-user.h"
+
+#include <glib.h>
+
+struct virtio_blk_inhdr {
+ unsigned char status;
+};
+
+/* vhost user block device */
+typedef struct VubDev {
+ VugDev parent;
+ int blk_fd;
+ struct virtio_blk_config blkcfg;
+ char *blk_name;
+ GMainLoop *loop;
+} VubDev;
+
+typedef struct VubReq {
+ VuVirtqElement *elem;
+ int64_t sector_num;
+ size_t size;
+ struct virtio_blk_inhdr *in;
+ struct virtio_blk_outhdr *out;
+ VubDev *vdev_blk;
+ struct VuVirtq *vq;
+} VubReq;
+
+/** refer util/iov.c **/
+static size_t vub_iov_size(const struct iovec *iov,
+ const unsigned int iov_cnt)
+{
+ size_t len;
+ unsigned int i;
+
+ len = 0;
+ for (i = 0; i < iov_cnt; i++) {
+ len += iov[i].iov_len;
+ }
+ return len;
+}
+
+static void vub_panic_cb(VuDev *vu_dev, const char *buf)
+{
+ VugDev *gdev;
+ VubDev *vdev_blk;
+
+ assert(vu_dev);
+
+ gdev = container_of(vu_dev, VugDev, parent);
+ vdev_blk = container_of(gdev, VubDev, parent);
+ if (buf) {
+ g_warning("vu_panic: %s", buf);
+ }
+
+ g_main_loop_quit(vdev_blk->loop);
+}
+
+static void vub_req_complete(VubReq *req)
+{
+ VugDev *gdev = &req->vdev_blk->parent;
+ VuDev *vu_dev = &gdev->parent;
+
+ /* IO size with 1 extra status byte */
+ vu_queue_push(vu_dev, req->vq, req->elem,
+ req->size + 1);
+ vu_queue_notify(vu_dev, req->vq);
+
+ if (req->elem) {
+ free(req->elem);
+ }
+ g_free(req);
+}
+
+static int vub_open(const char *file_name)
+{
+ int fd;
+
+ fd = open(file_name, O_RDWR | O_DIRECT);
+ if (fd < 0) {
+ fprintf(stderr, "Cannot open file %s, %s\n", file_name,
+ strerror(errno));
+ return -1;
+ }
+
+ return fd;
+}
+
+static void vub_close(int fd)
+{
+ if (fd >= 0) {
+ close(fd);
+ }
+}
+
+static ssize_t
+vub_readv(VubReq *req, struct iovec *iov, uint32_t iovcnt)
+{
+ VubDev *vdev_blk = req->vdev_blk;
+ ssize_t rc;
+
+ if (!iovcnt) {
+ fprintf(stderr, "Invalid Read IOV count\n");
+ return -1;
+ }
+
+ req->size = vub_iov_size(iov, iovcnt);
+ rc = preadv(vdev_blk->blk_fd, iov, iovcnt, req->sector_num * 512);
+ if (rc < 0) {
+ fprintf(stderr, "Block %s, Sector %"PRIu64", Size %lu Read Failed\n",
+ vdev_blk->blk_name, req->sector_num, req->size);
+ return -1;
+ }
+
+ return rc;
+}
+
+static ssize_t
+vub_writev(VubReq *req, struct iovec *iov, uint32_t iovcnt)
+{
+ VubDev *vdev_blk = req->vdev_blk;
+ ssize_t rc;
+
+ if (!iovcnt) {
+ fprintf(stderr, "Invalid Write IOV count\n");
+ return -1;
+ }
+
+ req->size = vub_iov_size(iov, iovcnt);
+ rc = pwritev(vdev_blk->blk_fd, iov, iovcnt, req->sector_num * 512);
+ if (rc < 0) {
+ fprintf(stderr, "Block %s, Sector %"PRIu64", Size %lu Write Failed\n",
+ vdev_blk->blk_name, req->sector_num, req->size);
+ return -1;
+ }
+
+ return rc;
+}
+
+static void
+vub_flush(VubReq *req)
+{
+ VubDev *vdev_blk = req->vdev_blk;
+
+ if (vdev_blk->blk_fd) {
+ fsync(vdev_blk->blk_fd);
+ }
+}
+
+
+static int vub_virtio_process_req(VubDev *vdev_blk,
+ VuVirtq *vq)
+{
+ VugDev *gdev = &vdev_blk->parent;
+ VuDev *vu_dev = &gdev->parent;
+ VuVirtqElement *elem;
+ uint32_t type;
+ unsigned in_num;
+ unsigned out_num;
+ VubReq *req;
+
+ elem = vu_queue_pop(vu_dev, vq, sizeof(VuVirtqElement));
+ if (!elem) {
+ return -1;
+ }
+
+ /* refer to hw/block/virtio_blk.c */
+ if (elem->out_num < 1 || elem->in_num < 1) {
+ fprintf(stderr, "virtio-blk request missing headers\n");
+ free(elem);
+ return -1;
+ }
+
+ req = g_new0(VubReq, 1);
+ req->vdev_blk = vdev_blk;
+ req->vq = vq;
+ req->elem = elem;
+
+ in_num = elem->in_num;
+ out_num = elem->out_num;
+
+ /* don't support VIRTIO_F_ANY_LAYOUT and virtio 1.0 only */
+ if (elem->out_sg[0].iov_len < sizeof(struct virtio_blk_outhdr)) {
+ fprintf(stderr, "Invalid outhdr size\n");
+ goto err;
+ }
+ req->out = (struct virtio_blk_outhdr *)elem->out_sg[0].iov_base;
+ out_num--;
+
+ if (elem->in_sg[in_num - 1].iov_len < sizeof(struct virtio_blk_inhdr)) {
+ fprintf(stderr, "Invalid inhdr size\n");
+ goto err;
+ }
+ req->in = (struct virtio_blk_inhdr *)elem->in_sg[in_num - 1].iov_base;
+ in_num--;
+
+ type = le32toh(req->out->type);
+ switch (type & ~(VIRTIO_BLK_T_OUT | VIRTIO_BLK_T_BARRIER)) {
+ case VIRTIO_BLK_T_IN: {
+ ssize_t ret = 0;
+ bool is_write = type & VIRTIO_BLK_T_OUT;
+ req->sector_num = le64toh(req->out->sector);
+ if (is_write) {
+ ret = vub_writev(req, &elem->out_sg[1], out_num);
+ } else {
+ ret = vub_readv(req, &elem->in_sg[0], in_num);
+ }
+ if (ret >= 0) {
+ req->in->status = VIRTIO_BLK_S_OK;
+ } else {
+ req->in->status = VIRTIO_BLK_S_IOERR;
+ }
+ vub_req_complete(req);
+ break;
+ }
+ case VIRTIO_BLK_T_FLUSH: {
+ vub_flush(req);
+ req->in->status = VIRTIO_BLK_S_OK;
+ vub_req_complete(req);
+ break;
+ }
+ case VIRTIO_BLK_T_GET_ID: {
+ size_t size = MIN(vub_iov_size(&elem->in_sg[0], in_num),
+ VIRTIO_BLK_ID_BYTES);
+ snprintf(elem->in_sg[0].iov_base, size, "%s", "vhost_user_blk");
+ req->in->status = VIRTIO_BLK_S_OK;
+ req->size = elem->in_sg[0].iov_len;
+ vub_req_complete(req);
+ break;
+ }
+ default: {
+ req->in->status = VIRTIO_BLK_S_UNSUPP;
+ vub_req_complete(req);
+ break;
+ }
+ }
+
+ return 0;
+
+err:
+ free(elem);
+ g_free(req);
+ return -1;
+}
+
+static void vub_process_vq(VuDev *vu_dev, int idx)
+{
+ VugDev *gdev;
+ VubDev *vdev_blk;
+ VuVirtq *vq;
+ int ret;
+
+ if ((idx < 0) || (idx >= VHOST_MAX_NR_VIRTQUEUE)) {
+ fprintf(stderr, "VQ Index out of range: %d\n", idx);
+ vub_panic_cb(vu_dev, NULL);
+ return;
+ }
+
+ gdev = container_of(vu_dev, VugDev, parent);
+ vdev_blk = container_of(gdev, VubDev, parent);
+ assert(vdev_blk);
+
+ vq = vu_get_queue(vu_dev, idx);
+ assert(vq);
+
+ while (1) {
+ ret = vub_virtio_process_req(vdev_blk, vq);
+ if (ret) {
+ break;
+ }
+ }
+}
+
+static void vub_queue_set_started(VuDev *vu_dev, int idx, bool started)
+{
+ VuVirtq *vq;
+
+ assert(vu_dev);
+
+ if ((idx < 0) || (idx >= VHOST_MAX_NR_VIRTQUEUE)) {
+ fprintf(stderr, "VQ Index out of range: %d\n", idx);
+ vub_panic_cb(vu_dev, NULL);
+ return;
+ }
+
+ vq = vu_get_queue(vu_dev, idx);
+ vu_set_queue_handler(vu_dev, vq, started ? vub_process_vq : NULL);
+}
+
+static uint64_t
+vub_get_features(VuDev *dev)
+{
+ return 1ull << VIRTIO_BLK_F_SIZE_MAX |
+ 1ull << VIRTIO_BLK_F_SEG_MAX |
+ 1ull << VIRTIO_BLK_F_TOPOLOGY |
+ 1ull << VIRTIO_BLK_F_BLK_SIZE |
+ 1ull << VIRTIO_F_VERSION_1 |
+ 1ull << VHOST_USER_F_PROTOCOL_FEATURES;
+}
+
+static int
+vub_get_config(VuDev *vu_dev, uint8_t *config, size_t len)
+{
+ VugDev *gdev;
+ VubDev *vdev_blk;
+
+ if (len != sizeof(struct virtio_blk_config)) {
+ return -1;
+ }
+ gdev = container_of(vu_dev, VugDev, parent);
+ vdev_blk = container_of(gdev, VubDev, parent);
+ memcpy(config, &vdev_blk->blkcfg, len);
+
+ return 0;
+}
+
+static const VuDevIface vub_iface = {
+ .get_features = vub_get_features,
+ .queue_set_started = vub_queue_set_started,
+ .get_config = vub_get_config,
+};
+
+static int unix_sock_new(char *unix_fn)
+{
+ int sock;
+ struct sockaddr_un un;
+ size_t len;
+
+ assert(unix_fn);
+
+ sock = socket(AF_UNIX, SOCK_STREAM, 0);
+ if (sock <= 0) {
+ perror("socket");
+ return -1;
+ }
+
+ un.sun_family = AF_UNIX;
+ (void)snprintf(un.sun_path, sizeof(un.sun_path), "%s", unix_fn);
+ len = sizeof(un.sun_family) + strlen(un.sun_path);
+
+ (void)unlink(unix_fn);
+ if (bind(sock, (struct sockaddr *)&un, len) < 0) {
+ perror("bind");
+ goto fail;
+ }
+
+ if (listen(sock, 1) < 0) {
+ perror("listen");
+ goto fail;
+ }
+
+ return sock;
+
+fail:
+ (void)close(sock);
+
+ return -1;
+}
+
+static void vub_deinit(struct VubDev *vdev_blk)
+{
+ if (!vdev_blk) {
+ return;
+ }
+
+ if (vdev_blk->blk_fd) {
+ vub_close(vdev_blk->blk_fd);
+ }
+}
+
+static void
+vub_initialize_config(int fd, struct virtio_blk_config *config)
+{
+ off64_t capacity;
+
+ capacity = lseek64(fd, 0, SEEK_END);
+ config->capacity = capacity >> 9;
+ config->blk_size = 512;
+ config->size_max = 65536;
+ config->seg_max = 128 - 2;
+ config->min_io_size = 1;
+ config->opt_io_size = 1;
+ config->num_queues = 1;
+}
+
+static int
+vub_new_block(VubDev *vdev_blk, char *blk_file)
+{
+ vdev_blk->blk_fd = vub_open(blk_file);
+ if (vdev_blk->blk_fd < 0) {
+ fprintf(stderr, "Error to open block device %s\n", blk_file);
+ return -1;
+ }
+ vdev_blk->blk_name = blk_file;
+
+ /* fill virtio_blk_config with block parameters */
+ vub_initialize_config(vdev_blk->blk_fd, &vdev_blk->blkcfg);
+
+ return 0;
+}
+
+int main(int argc, char **argv)
+{
+ int opt;
+ char *unix_socket = NULL;
+ char *blk_file = NULL;
+ int lsock = -1, csock = -1, rc;
+ VubDev *vdev_blk = NULL;
+
+ while ((opt = getopt(argc, argv, "b:h:s:")) != -1) {
+ switch (opt) {
+ case 'b':
+ blk_file = g_strdup(optarg);
+ break;
+ case 's':
+ unix_socket = g_strdup(optarg);
+ break;
+ case 'h':
+ default:
+ printf("Usage: %s [-b block device or file, -s UNIX domain socket]"
+ " | [ -h ]\n", argv[0]);
+ return -1;
+ }
+ }
+
+ if (!unix_socket || !blk_file) {
+ printf("Usage: %s [-b block device or file, -s UNIX domain socket] |"
+ " [ -h ]\n", argv[0]);
+ return -1;
+ }
+
+ lsock = unix_sock_new(unix_socket);
+ if (lsock < 0) {
+ goto err;
+ }
+
+ csock = accept(lsock, (void *)0, (void *)0);
+ if (csock < 0) {
+ fprintf(stderr, "Accept error %s\n", strerror(errno));
+ goto err;
+ }
+
+ vdev_blk = g_new0(VubDev, 1);
+ vdev_blk->loop = g_main_loop_new(NULL, FALSE);
+
+ rc = vub_new_block(vdev_blk, blk_file);
+ if (rc) {
+ goto err;
+ }
+
+ vug_init(&vdev_blk->parent, csock, vub_panic_cb, &vub_iface);
+
+ g_main_loop_run(vdev_blk->loop);
+
+ vug_deinit(&vdev_blk->parent);
+
+err:
+ if (vdev_blk) {
+ g_main_loop_unref(vdev_blk->loop);
+ vub_deinit(vdev_blk);
+ g_free(vdev_blk);
+ }
+ if (csock >= 0) {
+ close(csock);
+ }
+ if (lsock >= 0) {
+ close(lsock);
+ }
+ g_free(unix_socket);
+ g_free(blk_file);
+
+ return 0;
+}
+
This commit introcudes a vhost-user-blk backend device, it uses UNIX domain socket to communicate with Qemu. The vhost-user-blk sample application should be used with Qemu vhost-user-blk-pci device. To use it, complie with: make vhost-user-blk and start like this: vhost-user-blk -b /dev/sdb -s /path/vhost.socket Signed-off-by: Changpeng Liu <changpeng.liu@intel.com> --- .gitignore | 1 + Makefile | 3 + Makefile.objs | 1 + contrib/vhost-user-blk/Makefile.objs | 1 + contrib/vhost-user-blk/vhost-user-blk.c | 492 ++++++++++++++++++++++++++++++++ 5 files changed, 498 insertions(+) create mode 100644 contrib/vhost-user-blk/Makefile.objs create mode 100644 contrib/vhost-user-blk/vhost-user-blk.c