Introduce the vfio-user "proxy": this is the client code responsible for
sending and receiving vfio-user messages across the control socket.
The new files hw/vfio-user/proxy.[ch] contain some basic plumbing for
managing the proxy; initialize the proxy during realization of the
VFIOUserPCIDevice instance.
Originally-by: John Johnson <john.g.john...@oracle.com>
Signed-off-by: Elena Ufimtseva <elena.ufimts...@oracle.com>
Signed-off-by: Jagannathan Raman <jag.ra...@oracle.com>
Signed-off-by: John Levon <john.le...@nutanix.com>
---
hw/vfio-user/proxy.h | 82 +++++++++++++++++
include/hw/vfio/vfio-device.h | 2 +
hw/vfio-user/pci.c | 17 ++++
hw/vfio-user/proxy.c | 165 ++++++++++++++++++++++++++++++++++
hw/vfio-user/meson.build | 1 +
5 files changed, 267 insertions(+)
create mode 100644 hw/vfio-user/proxy.h
create mode 100644 hw/vfio-user/proxy.c
diff --git a/hw/vfio-user/proxy.h b/hw/vfio-user/proxy.h
new file mode 100644
index 0000000000..60fe3e0b6d
--- /dev/null
+++ b/hw/vfio-user/proxy.h
@@ -0,0 +1,82 @@
+#ifndef VFIO_USER_PROXY_H
+#define VFIO_USER_PROXY_H
+
+/*
+ * vfio protocol over a UNIX socket.
+ *
+ * Copyright © 2018, 2021 Oracle and/or its affiliates.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2. See
+ * the COPYING file in the top-level directory.
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include "io/channel.h"
+#include "io/channel-socket.h"
+
+typedef struct {
+ int send_fds;
+ int recv_fds;
+ int *fds;
+} VFIOUserFDs;
+
+enum msg_type {
+ VFIO_MSG_NONE,
+ VFIO_MSG_ASYNC,
+ VFIO_MSG_WAIT,
+ VFIO_MSG_NOWAIT,
+ VFIO_MSG_REQ,
+};
+
+typedef struct VFIOUserMsg {
+ QTAILQ_ENTRY(VFIOUserMsg) next;
+ VFIOUserFDs *fds;
+ uint32_t rsize;
+ uint32_t id;
+ QemuCond cv;
+ bool complete;
+ enum msg_type type;
+} VFIOUserMsg;
+
+
+enum proxy_state {
+ VFIO_PROXY_CONNECTED = 1,
+ VFIO_PROXY_ERROR = 2,
+ VFIO_PROXY_CLOSING = 3,
+ VFIO_PROXY_CLOSED = 4,
+};
+
+typedef QTAILQ_HEAD(VFIOUserMsgQ, VFIOUserMsg) VFIOUserMsgQ;
+
+typedef struct VFIOUserProxy {
+ QLIST_ENTRY(VFIOUserProxy) next;
+ char *sockname;
+ struct QIOChannel *ioc;
+ void (*request)(void *opaque, VFIOUserMsg *msg);
+ void *req_arg;
+ int flags;
+ QemuCond close_cv;
+ AioContext *ctx;
+ QEMUBH *req_bh;
+
+ /*
+ * above only changed when BQL is held
+ * below are protected by per-proxy lock
+ */
+ QemuMutex lock;
+ VFIOUserMsgQ free;
+ VFIOUserMsgQ pending;
+ VFIOUserMsgQ incoming;
+ VFIOUserMsgQ outgoing;
+ VFIOUserMsg *last_nowait;
+ enum proxy_state state;
+} VFIOUserProxy;
+
+/* VFIOProxy flags */
+#define VFIO_PROXY_CLIENT 0x1
+
+VFIOUserProxy *vfio_user_connect_dev(SocketAddress *addr, Error **errp);
+void vfio_user_disconnect(VFIOUserProxy *proxy);
+
+#endif /* VFIO_USER_PROXY_H */
diff --git a/include/hw/vfio/vfio-device.h b/include/hw/vfio/vfio-device.h
index a23ef4ea13..09f1a21bf8 100644
--- a/include/hw/vfio/vfio-device.h
+++ b/include/hw/vfio/vfio-device.h
@@ -46,6 +46,7 @@ typedef struct VFIOMigration VFIOMigration;
typedef struct IOMMUFDBackend IOMMUFDBackend;
typedef struct VFIOIOASHwpt VFIOIOASHwpt;
+typedef struct VFIOUserProxy VFIOUserProxy;
typedef struct VFIODevice {
QLIST_ENTRY(VFIODevice) next;
@@ -86,6 +87,7 @@ typedef struct VFIODevice {
QLIST_ENTRY(VFIODevice) hwpt_next;
struct vfio_region_info **reginfo;
int *region_fds;
+ VFIOUserProxy *proxy;
} VFIODevice;
struct VFIODeviceOps {
diff --git a/hw/vfio-user/pci.c b/hw/vfio-user/pci.c
index 181fe0f02e..f77d0e497d 100644
--- a/hw/vfio-user/pci.c
+++ b/hw/vfio-user/pci.c
@@ -14,6 +14,7 @@
#include "hw/qdev-properties.h"
#include "hw/vfio/pci.h"
+#include "hw/vfio-user/proxy.h"
#define TYPE_VFIO_USER_PCI "vfio-user-pci"
OBJECT_DECLARE_SIMPLE_TYPE(VFIOUserPCIDevice, VFIO_USER_PCI)
@@ -46,6 +47,8 @@ static void vfio_user_pci_realize(PCIDevice *pdev, Error
**errp)
VFIOPCIDevice *vdev = VFIO_PCI_BASE(pdev);
VFIODevice *vbasedev = &vdev->vbasedev;
AddressSpace *as;
+ SocketAddress addr;
+ VFIOUserProxy *proxy;
/*
* TODO: make option parser understand SocketAddress
@@ -58,6 +61,15 @@ static void vfio_user_pci_realize(PCIDevice *pdev, Error
**errp)
return;
}
+ memset(&addr, 0, sizeof(addr));
+ addr.type = SOCKET_ADDRESS_TYPE_UNIX;
+ addr.u.q_unix.path = udev->sock_name;
+ proxy = vfio_user_connect_dev(&addr, errp);
+ if (!proxy) {
+ return;
+ }
+ vbasedev->proxy = proxy;
+
vbasedev->name = g_strdup_printf("VFIO user <%s>", udev->sock_name);
/*
@@ -103,8 +115,13 @@ static void vfio_user_instance_init(Object *obj)
static void vfio_user_instance_finalize(Object *obj)
{
VFIOPCIDevice *vdev = VFIO_PCI_BASE(obj);
+ VFIODevice *vbasedev = &vdev->vbasedev;
vfio_pci_put_device(vdev);
+
+ if (vbasedev->proxy != NULL) {
+ vfio_user_disconnect(vbasedev->proxy);
+ }
}
static const Property vfio_user_pci_dev_properties[] = {
diff --git a/hw/vfio-user/proxy.c b/hw/vfio-user/proxy.c
new file mode 100644
index 0000000000..ac481553ba
--- /dev/null
+++ b/hw/vfio-user/proxy.c
@@ -0,0 +1,165 @@
+/*
+ * vfio protocol over a UNIX socket.
+ *
+ * Copyright © 2018, 2021 Oracle and/or its affiliates.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include "qemu/osdep.h"
+#include <sys/ioctl.h>
+
+#include "hw/vfio/vfio-device.h"
+#include "hw/vfio-user/proxy.h"
+#include "qapi/error.h"
+#include "qemu/error-report.h"
+#include "qemu/lockable.h"
+#include "system/iothread.h"
+
+static IOThread *vfio_user_iothread;
+
+static void vfio_user_shutdown(VFIOUserProxy *proxy);
+
+
+/*
+ * Functions called by main, CPU, or iothread threads
+ */
+
+static void vfio_user_shutdown(VFIOUserProxy *proxy)
+{
+ qio_channel_shutdown(proxy->ioc, QIO_CHANNEL_SHUTDOWN_READ, NULL);
+ qio_channel_set_aio_fd_handler(proxy->ioc, proxy->ctx, NULL,
+ proxy->ctx, NULL, NULL);
+}
+
+/*
+ * Functions only called by iothread
+ */
+
+static void vfio_user_cb(void *opaque)
+{
+ VFIOUserProxy *proxy = opaque;
+
+ QEMU_LOCK_GUARD(&proxy->lock);
+
+ proxy->state = VFIO_PROXY_CLOSED;
+ qemu_cond_signal(&proxy->close_cv);
+}
+
+
+/*
+ * Functions called by main or CPU threads
+ */
+
+static QLIST_HEAD(, VFIOUserProxy) vfio_user_sockets =
+ QLIST_HEAD_INITIALIZER(vfio_user_sockets);
+
+VFIOUserProxy *vfio_user_connect_dev(SocketAddress *addr, Error **errp)
+{
+ VFIOUserProxy *proxy;
+ QIOChannelSocket *sioc;
+ QIOChannel *ioc;
+ char *sockname;
+
+ if (addr->type != SOCKET_ADDRESS_TYPE_UNIX) {
+ error_setg(errp, "vfio_user_connect - bad address family");
+ return NULL;
+ }
+ sockname = addr->u.q_unix.path;
+
+ sioc = qio_channel_socket_new();
+ ioc = QIO_CHANNEL(sioc);
+ if (qio_channel_socket_connect_sync(sioc, addr, errp)) {
+ object_unref(OBJECT(ioc));
+ return NULL;
+ }
+ qio_channel_set_blocking(ioc, false, NULL);
+
+ proxy = g_malloc0(sizeof(VFIOUserProxy));
+ proxy->sockname = g_strdup_printf("unix:%s", sockname);
+ proxy->ioc = ioc;
+ proxy->flags = VFIO_PROXY_CLIENT;
+ proxy->state = VFIO_PROXY_CONNECTED;
+
+ qemu_mutex_init(&proxy->lock);
+ qemu_cond_init(&proxy->close_cv);
+
+ if (vfio_user_iothread == NULL) {
+ vfio_user_iothread = iothread_create("VFIO user", errp);
+ }
+
+ proxy->ctx = iothread_get_aio_context(vfio_user_iothread);
+
+ QTAILQ_INIT(&proxy->outgoing);
+ QTAILQ_INIT(&proxy->incoming);
+ QTAILQ_INIT(&proxy->free);
+ QTAILQ_INIT(&proxy->pending);
+ QLIST_INSERT_HEAD(&vfio_user_sockets, proxy, next);
+
+ return proxy;
+}
+
+void vfio_user_disconnect(VFIOUserProxy *proxy)
+{
+ VFIOUserMsg *r1, *r2;
+
+ qemu_mutex_lock(&proxy->lock);
+
+ /* our side is quitting */
+ if (proxy->state == VFIO_PROXY_CONNECTED) {
+ vfio_user_shutdown(proxy);
+ if (!QTAILQ_EMPTY(&proxy->pending)) {
+ error_printf("vfio_user_disconnect: outstanding requests\n");
+ }
+ }
+ object_unref(OBJECT(proxy->ioc));
+ proxy->ioc = NULL;
+
+ proxy->state = VFIO_PROXY_CLOSING;
+ QTAILQ_FOREACH_SAFE(r1, &proxy->outgoing, next, r2) {
+ qemu_cond_destroy(&r1->cv);
+ QTAILQ_REMOVE(&proxy->outgoing, r1, next);
+ g_free(r1);
+ }
+ QTAILQ_FOREACH_SAFE(r1, &proxy->incoming, next, r2) {
+ qemu_cond_destroy(&r1->cv);
+ QTAILQ_REMOVE(&proxy->incoming, r1, next);
+ g_free(r1);
+ }
+ QTAILQ_FOREACH_SAFE(r1, &proxy->pending, next, r2) {
+ qemu_cond_destroy(&r1->cv);
+ QTAILQ_REMOVE(&proxy->pending, r1, next);
+ g_free(r1);
+ }
+ QTAILQ_FOREACH_SAFE(r1, &proxy->free, next, r2) {
+ qemu_cond_destroy(&r1->cv);
+ QTAILQ_REMOVE(&proxy->free, r1, next);
+ g_free(r1);
+ }
+
+ /*
+ * Make sure the iothread isn't blocking anywhere
+ * with a ref to this proxy by waiting for a BH
+ * handler to run after the proxy fd handlers were
+ * deleted above.
+ */
+ aio_bh_schedule_oneshot(proxy->ctx, vfio_user_cb, proxy);
+ qemu_cond_wait(&proxy->close_cv, &proxy->lock);
+
+ /* we now hold the only ref to proxy */
+ qemu_mutex_unlock(&proxy->lock);
+ qemu_cond_destroy(&proxy->close_cv);
+ qemu_mutex_destroy(&proxy->lock);
+
+ QLIST_REMOVE(proxy, next);
+ if (QLIST_EMPTY(&vfio_user_sockets)) {
+ iothread_destroy(vfio_user_iothread);
+ vfio_user_iothread = NULL;
+ }
+
+ g_free(proxy->sockname);
+ g_free(proxy);
+}
diff --git a/hw/vfio-user/meson.build b/hw/vfio-user/meson.build
index f1fee70c85..695b341547 100644
--- a/hw/vfio-user/meson.build
+++ b/hw/vfio-user/meson.build
@@ -2,6 +2,7 @@ vfio_user_ss = ss.source_set()
vfio_user_ss.add(files(
'container.c',
'pci.c',
+ 'proxy.c',
))
if get_option('vfio_user_client').enabled()
--
2.43.0
