From: "Dr. David Alan Gilbert" <dgilb...@redhat.com>
The virtio-fs virtio device provides shared file system access using
the FUSE protocol carried ovew virtio.
The actual file server is implemented in an external vhost-user-fs device
backend process.
Signed-off-by: Stefan Hajnoczi <stefa...@redhat.com>
Signed-off-by: Sebastien Boeuf <sebastien.bo...@intel.com>
Signed-off-by: Dr. David Alan Gilbert <dgilb...@redhat.com>
---
configure | 13 +
hw/virtio/Makefile.objs | 1 +
hw/virtio/vhost-user-fs.c | 297 ++++++++++++++++++++
include/hw/virtio/vhost-user-fs.h | 45 +++
include/standard-headers/linux/virtio_fs.h | 41 +++
include/standard-headers/linux/virtio_ids.h | 1 +
6 files changed, 398 insertions(+)
create mode 100644 hw/virtio/vhost-user-fs.c
create mode 100644 include/hw/virtio/vhost-user-fs.h
create mode 100644 include/standard-headers/linux/virtio_fs.h
diff --git a/configure b/configure
index 0173db5d9f..d77996dd24 100755
--- a/configure
+++ b/configure
@@ -382,6 +382,7 @@ vhost_crypto=""
vhost_scsi=""
vhost_vsock=""
vhost_user=""
+vhost_user_fs=""
kvm="no"
hax="no"
hvf="no"
@@ -1316,6 +1317,10 @@ for opt do
;;
--enable-vhost-vsock) vhost_vsock="yes"
;;
+ --disable-vhost-user-fs) vhost_user_fs="no"
+ ;;
+ --enable-vhost-user-fs) vhost_user_fs="yes"
+ ;;
--disable-opengl) opengl="no"
;;
--enable-opengl) opengl="yes"
@@ -2269,6 +2274,10 @@ test "$vhost_crypto" = "" && vhost_crypto=$vhost_user
if test "$vhost_crypto" = "yes" && test "$vhost_user" = "no"; then
error_exit "--enable-vhost-crypto requires --enable-vhost-user"
fi
+test "$vhost_user_fs" = "" && vhost_user_fs=$vhost_user
+if test "$vhost_user_fs" = "yes" && test "$vhost_user" = "no"; then
+ error_exit "--enable-vhost-user-fs requires --enable-vhost-user"
+fi
# OR the vhost-kernel and vhost-user values for simplicity
if test "$vhost_net" = ""; then
@@ -6422,6 +6431,7 @@ echo "vhost-crypto support $vhost_crypto"
echo "vhost-scsi support $vhost_scsi"
echo "vhost-vsock support $vhost_vsock"
echo "vhost-user support $vhost_user"
+echo "vhost-user-fs support $vhost_user_fs"
echo "Trace backends $trace_backends"
if have_backend "simple"; then
echo "Trace output file $trace_file-<pid>"
@@ -6918,6 +6928,9 @@ fi
if test "$vhost_user" = "yes" ; then
echo "CONFIG_VHOST_USER=y" >> $config_host_mak
fi
+if test "$vhost_user_fs" = "yes" ; then
+ echo "CONFIG_VHOST_USER_FS=y" >> $config_host_mak
+fi
if test "$blobs" = "yes" ; then
echo "INSTALL_BLOBS=yes" >> $config_host_mak
fi
diff --git a/hw/virtio/Makefile.objs b/hw/virtio/Makefile.objs
index 964ce78607..47ffbf22c4 100644
--- a/hw/virtio/Makefile.objs
+++ b/hw/virtio/Makefile.objs
@@ -11,6 +11,7 @@ common-obj-$(CONFIG_VIRTIO_PCI) += virtio-pci.o
common-obj-$(CONFIG_VIRTIO_MMIO) += virtio-mmio.o
obj-$(CONFIG_VIRTIO_BALLOON) += virtio-balloon.o
obj-$(CONFIG_VIRTIO_CRYPTO) += virtio-crypto.o
+obj-$(CONFIG_VHOST_USER_FS) += vhost-user-fs.o
obj-$(call land,$(CONFIG_VIRTIO_CRYPTO),$(CONFIG_VIRTIO_PCI)) +=
virtio-crypto-pci.o
obj-$(CONFIG_VIRTIO_PMEM) += virtio-pmem.o
common-obj-$(call land,$(CONFIG_VIRTIO_PMEM),$(CONFIG_VIRTIO_PCI)) +=
virtio-pmem-pci.o
diff --git a/hw/virtio/vhost-user-fs.c b/hw/virtio/vhost-user-fs.c
new file mode 100644
index 0000000000..72e270d869
--- /dev/null
+++ b/hw/virtio/vhost-user-fs.c
@@ -0,0 +1,297 @@
+/*
+ * Vhost-user filesystem virtio device
+ *
+ * Copyright 2018 Red Hat, Inc.
+ *
+ * Authors:
+ * Stefan Hajnoczi <stefa...@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or
+ * (at your option) any later version. See the COPYING file in the
+ * top-level directory.
+ */
+
+#include "qemu/osdep.h"
+#include <sys/ioctl.h>
+#include "standard-headers/linux/virtio_fs.h"
+#include "qapi/error.h"
+#include "hw/qdev-properties.h"
+#include "hw/virtio/virtio-bus.h"
+#include "hw/virtio/virtio-access.h"
+#include "qemu/error-report.h"
+#include "hw/virtio/vhost-user-fs.h"
+#include "monitor/monitor.h"
+
+static void vuf_get_config(VirtIODevice *vdev, uint8_t *config)
+{
+ VHostUserFS *fs = VHOST_USER_FS(vdev);
+ struct virtio_fs_config fscfg = {};
+
+ memcpy((char *)fscfg.tag, fs->conf.tag,
+ MIN(strlen(fs->conf.tag) + 1, sizeof(fscfg.tag)));
+
+ virtio_stl_p(vdev, &fscfg.num_request_queues, fs->conf.num_request_queues);
+
+ memcpy(config, &fscfg, sizeof(fscfg));
+}
+
+static void vuf_start(VirtIODevice *vdev)
+{
+ VHostUserFS *fs = VHOST_USER_FS(vdev);
+ BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
+ VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
+ int ret;
+ int i;
+
+ if (!k->set_guest_notifiers) {
+ error_report("binding does not support guest notifiers");
+ return;
+ }
+
+ ret = vhost_dev_enable_notifiers(&fs->vhost_dev, vdev);
+ if (ret < 0) {
+ error_report("Error enabling host notifiers: %d", -ret);
+ return;
+ }
+
+ ret = k->set_guest_notifiers(qbus->parent, fs->vhost_dev.nvqs, true);
+ if (ret < 0) {
+ error_report("Error binding guest notifier: %d", -ret);
+ goto err_host_notifiers;
+ }
+
+ fs->vhost_dev.acked_features = vdev->guest_features;
+ ret = vhost_dev_start(&fs->vhost_dev, vdev);
+ if (ret < 0) {
+ error_report("Error starting vhost: %d", -ret);
+ goto err_guest_notifiers;
+ }
+
+ /*
+ * guest_notifier_mask/pending not used yet, so just unmask
+ * everything here. virtio-pci will do the right thing by
+ * enabling/disabling irqfd.
+ */
+ for (i = 0; i < fs->vhost_dev.nvqs; i++) {
+ vhost_virtqueue_mask(&fs->vhost_dev, vdev, i, false);
+ }
+
+ return;
+
+err_guest_notifiers:
+ k->set_guest_notifiers(qbus->parent, fs->vhost_dev.nvqs, false);
+err_host_notifiers:
+ vhost_dev_disable_notifiers(&fs->vhost_dev, vdev);
+}
+
+static void vuf_stop(VirtIODevice *vdev)
+{
+ VHostUserFS *fs = VHOST_USER_FS(vdev);
+ BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
+ VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
+ int ret;
+
+ if (!k->set_guest_notifiers) {
+ return;
+ }
+
+ vhost_dev_stop(&fs->vhost_dev, vdev);
+
+ ret = k->set_guest_notifiers(qbus->parent, fs->vhost_dev.nvqs, false);
+ if (ret < 0) {
+ error_report("vhost guest notifier cleanup failed: %d", ret);
+ return;
+ }
+
+ vhost_dev_disable_notifiers(&fs->vhost_dev, vdev);
+}
+
+static void vuf_set_status(VirtIODevice *vdev, uint8_t status)
+{
+ VHostUserFS *fs = VHOST_USER_FS(vdev);
+ bool should_start = status & VIRTIO_CONFIG_S_DRIVER_OK;
+
+ if (!vdev->vm_running) {
+ should_start = false;
+ }
+
+ if (fs->vhost_dev.started == should_start) {
+ return;
+ }
+
+ if (should_start) {
+ vuf_start(vdev);
+ } else {
+ vuf_stop(vdev);
+ }
+}
+
+static uint64_t vuf_get_features(VirtIODevice *vdev,
+ uint64_t requested_features,
+ Error **errp)
+{
+ /* No feature bits used yet */
+ return requested_features;
+}
+
+static void vuf_handle_output(VirtIODevice *vdev, VirtQueue *vq)
+{
+ /* Do nothing */
+ g_assert_not_reached();
+}
+
+static void vuf_guest_notifier_mask(VirtIODevice *vdev, int idx,
+ bool mask)
+{
+ VHostUserFS *fs = VHOST_USER_FS(vdev);
+
+ vhost_virtqueue_mask(&fs->vhost_dev, vdev, idx, mask);
+}
+
+static bool vuf_guest_notifier_pending(VirtIODevice *vdev, int idx)
+{
+ VHostUserFS *fs = VHOST_USER_FS(vdev);
+
+ return vhost_virtqueue_pending(&fs->vhost_dev, idx);
+}
+
+static void vuf_device_realize(DeviceState *dev, Error **errp)
+{
+ VirtIODevice *vdev = VIRTIO_DEVICE(dev);
+ VHostUserFS *fs = VHOST_USER_FS(dev);
+ unsigned int i;
+ size_t len;
+ int ret;
+
+ if (!fs->conf.chardev.chr) {
+ error_setg(errp, "missing chardev");
+ return;
+ }
+
+ if (!fs->conf.tag) {
+ error_setg(errp, "missing tag property");
+ return;
+ }
+ len = strlen(fs->conf.tag);
+ if (len == 0) {
+ error_setg(errp, "tag property cannot be empty");
+ return;
+ }
+ if (len > sizeof_field(struct virtio_fs_config, tag)) {
+ error_setg(errp, "tag property must be %zu bytes or less",
+ sizeof_field(struct virtio_fs_config, tag));
+ return;
+ }
+
+ if (fs->conf.num_request_queues == 0) {
+ error_setg(errp, "num-request-queues property must be larger than 0");
+ return;
+ }
+
+ if (!is_power_of_2(fs->conf.queue_size)) {
+ error_setg(errp, "queue-size property must be a power of 2");
+ return;
+ }
+
+ if (fs->conf.queue_size > VIRTQUEUE_MAX_SIZE) {
+ error_setg(errp, "queue-size property must be %u or smaller",
+ VIRTQUEUE_MAX_SIZE);
+ return;
+ }
+
+ if (!vhost_user_init(&fs->vhost_user, &fs->conf.chardev, errp)) {
+ return;
+ }
+
+ virtio_init(vdev, "vhost-user-fs", VIRTIO_ID_FS,
+ sizeof(struct virtio_fs_config));
+
+ /* Hiprio queue */
+ virtio_add_queue(vdev, fs->conf.queue_size, vuf_handle_output);
+
+ /* Request queues */
+ for (i = 0; i < fs->conf.num_request_queues; i++) {
+ virtio_add_queue(vdev, fs->conf.queue_size, vuf_handle_output);
+ }
+
+ /* 1 high prio queue, plus the number configured */
+ fs->vhost_dev.nvqs = 1 + fs->conf.num_request_queues;
+ fs->vhost_dev.vqs = g_new0(struct vhost_virtqueue, fs->vhost_dev.nvqs);
+ ret = vhost_dev_init(&fs->vhost_dev, &fs->vhost_user,
+ VHOST_BACKEND_TYPE_USER, 0);
+ if (ret < 0) {
+ error_setg_errno(errp, -ret, "vhost_dev_init failed");
+ goto err_virtio;
+ }
+
+ return;
+
+err_virtio:
+ vhost_user_cleanup(&fs->vhost_user);
+ virtio_cleanup(vdev);
+ g_free(fs->vhost_dev.vqs);
+ return;
+}
+
+static void vuf_device_unrealize(DeviceState *dev, Error **errp)
+{
+ VirtIODevice *vdev = VIRTIO_DEVICE(dev);
+ VHostUserFS *fs = VHOST_USER_FS(dev);
+
+ /* This will stop vhost backend if appropriate. */
+ vuf_set_status(vdev, 0);
+
+ vhost_dev_cleanup(&fs->vhost_dev);
+
+ vhost_user_cleanup(&fs->vhost_user);
+
+ virtio_cleanup(vdev);
+ g_free(fs->vhost_dev.vqs);
+ fs->vhost_dev.vqs = NULL;
+}
+
+static const VMStateDescription vuf_vmstate = {
+ .name = "vhost-user-fs",
+ .unmigratable = 1,
+};
+
+static Property vuf_properties[] = {
+ DEFINE_PROP_CHR("chardev", VHostUserFS, conf.chardev),
+ DEFINE_PROP_STRING("tag", VHostUserFS, conf.tag),
+ DEFINE_PROP_UINT16("num-request-queues", VHostUserFS,
+ conf.num_request_queues, 1),
+ DEFINE_PROP_UINT16("queue-size", VHostUserFS, conf.queue_size, 128),
+ DEFINE_PROP_STRING("vhostfd", VHostUserFS, conf.vhostfd),
+ DEFINE_PROP_END_OF_LIST(),
+};
+
+static void vuf_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+ VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
+
+ dc->props = vuf_properties;
+ dc->vmsd = &vuf_vmstate;
+ set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
+ vdc->realize = vuf_device_realize;
+ vdc->unrealize = vuf_device_unrealize;
+ vdc->get_features = vuf_get_features;
+ vdc->get_config = vuf_get_config;
+ vdc->set_status = vuf_set_status;
+ vdc->guest_notifier_mask = vuf_guest_notifier_mask;
+ vdc->guest_notifier_pending = vuf_guest_notifier_pending;
+}
+
+static const TypeInfo vuf_info = {
+ .name = TYPE_VHOST_USER_FS,
+ .parent = TYPE_VIRTIO_DEVICE,
+ .instance_size = sizeof(VHostUserFS),
+ .class_init = vuf_class_init,
+};
+
+static void vuf_register_types(void)
+{
+ type_register_static(&vuf_info);
+}
+
+type_init(vuf_register_types)
diff --git a/include/hw/virtio/vhost-user-fs.h
b/include/hw/virtio/vhost-user-fs.h
new file mode 100644
index 0000000000..7f1c8742b1
--- /dev/null
+++ b/include/hw/virtio/vhost-user-fs.h
@@ -0,0 +1,45 @@
+/*
+ * Vhost-user filesystem virtio device
+ *
+ * Copyright 2018 Red Hat, Inc.
+ *
+ * Authors:
+ * Stefan Hajnoczi <stefa...@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or
+ * (at your option) any later version. See the COPYING file in the
+ * top-level directory.
+ */
+
+#ifndef _QEMU_VHOST_USER_FS_H
+#define _QEMU_VHOST_USER_FS_H
+
+#include "hw/virtio/virtio.h"
+#include "hw/virtio/vhost.h"
+#include "hw/virtio/vhost-user.h"
+#include "chardev/char-fe.h"
+
+#define TYPE_VHOST_USER_FS "x-vhost-user-fs-device"
+#define VHOST_USER_FS(obj) \
+ OBJECT_CHECK(VHostUserFS, (obj), TYPE_VHOST_USER_FS)
+
+typedef struct {
+ CharBackend chardev;
+ char *tag;
+ uint16_t num_request_queues;
+ uint16_t queue_size;
+ char *vhostfd;
+} VHostUserFSConf;
+
+typedef struct {
+ /*< private >*/
+ VirtIODevice parent;
+ VHostUserFSConf conf;
+ struct vhost_virtqueue *vhost_vqs;
+ struct vhost_dev vhost_dev;
+ VhostUserState vhost_user;
+
+ /*< public >*/
+} VHostUserFS;
+
+#endif /* _QEMU_VHOST_USER_FS_H */
diff --git a/include/standard-headers/linux/virtio_fs.h
b/include/standard-headers/linux/virtio_fs.h
new file mode 100644
index 0000000000..00bd7a6fa7
--- /dev/null
+++ b/include/standard-headers/linux/virtio_fs.h
@@ -0,0 +1,41 @@
+#ifndef _LINUX_VIRTIO_FS_H
+#define _LINUX_VIRTIO_FS_H
+/* This header is BSD licensed so anyone can use the definitions to implement
+ * compatible drivers/servers.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of IBM nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS
IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL IBM OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE. */
+#include "standard-headers/linux/types.h"
+#include "standard-headers/linux/virtio_ids.h"
+#include "standard-headers/linux/virtio_config.h"
+#include "standard-headers/linux/virtio_types.h"
+
+struct virtio_fs_config {
+ /* Filesystem name (UTF-8, not NUL-terminated, padded with NULs) */
+ uint8_t tag[36];
+
+ /* Number of request queues */
+ uint32_t num_request_queues;
+} QEMU_PACKED;
+
+#endif /* _LINUX_VIRTIO_FS_H */
diff --git a/include/standard-headers/linux/virtio_ids.h
b/include/standard-headers/linux/virtio_ids.h
index 32b2f94d1f..73fc004807 100644
--- a/include/standard-headers/linux/virtio_ids.h
+++ b/include/standard-headers/linux/virtio_ids.h
@@ -43,6 +43,7 @@
#define VIRTIO_ID_INPUT 18 /* virtio input */
#define VIRTIO_ID_VSOCK 19 /* virtio vsock transport */
#define VIRTIO_ID_CRYPTO 20 /* virtio crypto */
+#define VIRTIO_ID_FS 26 /* virtio filesystem */
#define VIRTIO_ID_PMEM 27 /* virtio pmem */
#endif /* _LINUX_VIRTIO_IDS_H */
--
2.21.0
