From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Date: Mon, 27 Jan 2020 19:00:57 +0000
Subject: [PATCH] virtiofsd: Start wiring up vhost-user
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Listen on our unix socket for the connection from QEMU, when we get it
initialise vhost-user and dive into our own loop variant (currently
dummy).
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
(cherry picked from commit f6f3573c6f271af5ded63ce28589a113f7205c72)
---
tools/virtiofsd/fuse_i.h | 4 ++
tools/virtiofsd/fuse_lowlevel.c | 5 ++
tools/virtiofsd/fuse_lowlevel.h | 7 +++
tools/virtiofsd/fuse_virtio.c | 87 +++++++++++++++++++++++++++++++-
tools/virtiofsd/fuse_virtio.h | 2 +
tools/virtiofsd/passthrough_ll.c | 7 +--
6 files changed, 106 insertions(+), 6 deletions(-)
diff --git a/tools/virtiofsd/fuse_i.h b/tools/virtiofsd/fuse_i.h
index 82d6ac7115..ec04449069 100644
--- a/tools/virtiofsd/fuse_i.h
+++ b/tools/virtiofsd/fuse_i.h
@@ -13,6 +13,8 @@
#include "fuse.h"
#include "fuse_lowlevel.h"
+struct fv_VuDev;
+
struct fuse_req {
struct fuse_session *se;
uint64_t unique;
@@ -65,6 +67,8 @@ struct fuse_session {
size_t bufsize;
int error;
char *vu_socket_path;
+ int vu_socketfd;
+ struct fv_VuDev *virtio_dev;
};
struct fuse_chan {
diff --git a/tools/virtiofsd/fuse_lowlevel.c b/tools/virtiofsd/fuse_lowlevel.c
index 5df124e64b..af09fa2b94 100644
--- a/tools/virtiofsd/fuse_lowlevel.c
+++ b/tools/virtiofsd/fuse_lowlevel.c
@@ -2242,6 +2242,11 @@ void fuse_session_unmount(struct fuse_session *se)
{
}
+int fuse_lowlevel_is_virtio(struct fuse_session *se)
+{
+ return se->vu_socket_path != NULL;
+}
+
#ifdef linux
int fuse_req_getgroups(fuse_req_t req, int size, gid_t list[])
{
diff --git a/tools/virtiofsd/fuse_lowlevel.h b/tools/virtiofsd/fuse_lowlevel.h
index 2fa225d40b..f6b34700af 100644
--- a/tools/virtiofsd/fuse_lowlevel.h
+++ b/tools/virtiofsd/fuse_lowlevel.h
@@ -1755,6 +1755,13 @@ void fuse_req_interrupt_func(fuse_req_t req, fuse_interrupt_func_t func,
*/
int fuse_req_interrupted(fuse_req_t req);
+/**
+ * Check if the session is connected via virtio
+ *
+ * @param se session object
+ * @return 1 if the session is a virtio session
+ */
+int fuse_lowlevel_is_virtio(struct fuse_session *se);
/*
* Inquiry functions
diff --git a/tools/virtiofsd/fuse_virtio.c b/tools/virtiofsd/fuse_virtio.c
index cbef6ffdda..2ae3c764dd 100644
--- a/tools/virtiofsd/fuse_virtio.c
+++ b/tools/virtiofsd/fuse_virtio.c
@@ -19,18 +19,78 @@
#include <stdint.h>
#include <stdio.h>
+#include <stdlib.h>
#include <string.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <sys/un.h>
#include <unistd.h>
+#include "contrib/libvhost-user/libvhost-user.h"
+
+/*
+ * We pass the dev element into libvhost-user
+ * and then use it to get back to the outer
+ * container for other data.
+ */
+struct fv_VuDev {
+ VuDev dev;
+ struct fuse_session *se;
+};
+
/* From spec */
struct virtio_fs_config {
char tag[36];
uint32_t num_queues;
};
+/*
+ * Callback from libvhost-user if there's a new fd we're supposed to listen
+ * to, typically a queue kick?
+ */
+static void fv_set_watch(VuDev *dev, int fd, int condition, vu_watch_cb cb,
+ void *data)
+{
+ fuse_log(FUSE_LOG_WARNING, "%s: TODO! fd=%d\n", __func__, fd);
+}
+
+/*
+ * Callback from libvhost-user if we're no longer supposed to listen on an fd
+ */
+static void fv_remove_watch(VuDev *dev, int fd)
+{
+ fuse_log(FUSE_LOG_WARNING, "%s: TODO! fd=%d\n", __func__, fd);
+}
+
+/* Callback from libvhost-user to panic */
+static void fv_panic(VuDev *dev, const char *err)
+{
+ fuse_log(FUSE_LOG_ERR, "%s: libvhost-user: %s\n", __func__, err);
+ /* TODO: Allow reconnects?? */
+ exit(EXIT_FAILURE);
+}
+
+static bool fv_queue_order(VuDev *dev, int qidx)
+{
+ return false;
+}
+
+static const VuDevIface fv_iface = {
+ /* TODO: Add other callbacks */
+ .queue_is_processed_in_order = fv_queue_order,
+};
+
+int virtio_loop(struct fuse_session *se)
+{
+ fuse_log(FUSE_LOG_INFO, "%s: Entry\n", __func__);
+
+ while (1) {
+ /* TODO: Add stuffing */
+ }
+
+ fuse_log(FUSE_LOG_INFO, "%s: Exit\n", __func__);
+}
+
int virtio_session_mount(struct fuse_session *se)
{
struct sockaddr_un un;
@@ -75,5 +135,30 @@ int virtio_session_mount(struct fuse_session *se)
return -1;
}
- return -1;
+ fuse_log(FUSE_LOG_INFO, "%s: Waiting for vhost-user socket connection...\n",
+ __func__);
+ int data_sock = accept(listen_sock, NULL, NULL);
+ if (data_sock == -1) {
+ fuse_log(FUSE_LOG_ERR, "vhost socket accept: %m\n");
+ close(listen_sock);
+ return -1;
+ }
+ close(listen_sock);
+ fuse_log(FUSE_LOG_INFO, "%s: Received vhost-user socket connection\n",
+ __func__);
+
+ /* TODO: Some cleanup/deallocation! */
+ se->virtio_dev = calloc(sizeof(struct fv_VuDev), 1);
+ if (!se->virtio_dev) {
+ fuse_log(FUSE_LOG_ERR, "%s: virtio_dev calloc failed\n", __func__);
+ close(data_sock);
+ return -1;
+ }
+
+ se->vu_socketfd = data_sock;
+ se->virtio_dev->se = se;
+ vu_init(&se->virtio_dev->dev, 2, se->vu_socketfd, fv_panic, fv_set_watch,
+ fv_remove_watch, &fv_iface);
+
+ return 0;
}
diff --git a/tools/virtiofsd/fuse_virtio.h b/tools/virtiofsd/fuse_virtio.h
index 8f2edb69ca..23026d6e4c 100644
--- a/tools/virtiofsd/fuse_virtio.h
+++ b/tools/virtiofsd/fuse_virtio.h
@@ -20,4 +20,6 @@ struct fuse_session;
int virtio_session_mount(struct fuse_session *se);
+int virtio_loop(struct fuse_session *se);
+
#endif
diff --git a/tools/virtiofsd/passthrough_ll.c b/tools/virtiofsd/passthrough_ll.c
index fc9b264d56..037c5d7b26 100644
--- a/tools/virtiofsd/passthrough_ll.c
+++ b/tools/virtiofsd/passthrough_ll.c
@@ -36,6 +36,7 @@
*/
#include "qemu/osdep.h"
+#include "fuse_virtio.h"
#include "fuse_lowlevel.h"
#include <assert.h>
#include <dirent.h>
@@ -1395,11 +1396,7 @@ int main(int argc, char *argv[])
fuse_daemonize(opts.foreground);
/* Block until ctrl+c or fusermount -u */
- if (opts.singlethread) {
- ret = fuse_session_loop(se);
- } else {
- ret = fuse_session_loop_mt(se, opts.clone_fd);
- }
+ ret = virtio_loop(se);
fuse_session_unmount(se);
err_out3: