qemu/contrib/libvhost-user/libvhost-user-glib.c
Coiby Xu 049f55502a libvhost-user: Allow vu_message_read to be replaced
Allow vu_message_read to be replaced by one which will make use of the
QIOChannel functions. Thus reading vhost-user message won't stall the
guest. For slave channel, we still use the default vu_message_read.

Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Coiby Xu <coiby.xu@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20200918080912.321299-2-coiby.xu@gmail.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-10-23 13:42:16 +01:00

171 lines
3.5 KiB
C

/*
* Vhost User library
*
* Copyright (c) 2016 Nutanix Inc. All rights reserved.
* Copyright (c) 2017 Red Hat, Inc.
*
* Authors:
* Marc-André Lureau <mlureau@redhat.com>
* Felipe Franciosi <felipe@nutanix.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 "libvhost-user-glib.h"
/* glib event loop integration for libvhost-user and misc callbacks */
G_STATIC_ASSERT((int)G_IO_IN == (int)VU_WATCH_IN);
G_STATIC_ASSERT((int)G_IO_OUT == (int)VU_WATCH_OUT);
G_STATIC_ASSERT((int)G_IO_PRI == (int)VU_WATCH_PRI);
G_STATIC_ASSERT((int)G_IO_ERR == (int)VU_WATCH_ERR);
G_STATIC_ASSERT((int)G_IO_HUP == (int)VU_WATCH_HUP);
typedef struct VugSrc {
GSource parent;
VuDev *dev;
GPollFD gfd;
} VugSrc;
static gboolean
vug_src_prepare(GSource *gsrc, gint *timeout)
{
g_assert(timeout);
*timeout = -1;
return FALSE;
}
static gboolean
vug_src_check(GSource *gsrc)
{
VugSrc *src = (VugSrc *)gsrc;
g_assert(src);
return src->gfd.revents & src->gfd.events;
}
static gboolean
vug_src_dispatch(GSource *gsrc, GSourceFunc cb, gpointer data)
{
VugSrc *src = (VugSrc *)gsrc;
g_assert(src);
((vu_watch_cb)cb)(src->dev, src->gfd.revents, data);
return G_SOURCE_CONTINUE;
}
static GSourceFuncs vug_src_funcs = {
vug_src_prepare,
vug_src_check,
vug_src_dispatch,
NULL
};
GSource *
vug_source_new(VugDev *gdev, int fd, GIOCondition cond,
vu_watch_cb vu_cb, gpointer data)
{
VuDev *dev = &gdev->parent;
GSource *gsrc;
VugSrc *src;
guint id;
g_assert(gdev);
g_assert(fd >= 0);
g_assert(vu_cb);
gsrc = g_source_new(&vug_src_funcs, sizeof(VugSrc));
g_source_set_callback(gsrc, (GSourceFunc)vu_cb, data, NULL);
src = (VugSrc *)gsrc;
src->dev = dev;
src->gfd.fd = fd;
src->gfd.events = cond;
g_source_add_poll(gsrc, &src->gfd);
id = g_source_attach(gsrc, g_main_context_get_thread_default());
g_assert(id);
return gsrc;
}
static void
set_watch(VuDev *vu_dev, int fd, int vu_evt, vu_watch_cb cb, void *pvt)
{
GSource *src;
VugDev *dev;
g_assert(vu_dev);
g_assert(fd >= 0);
g_assert(cb);
dev = container_of(vu_dev, VugDev, parent);
src = vug_source_new(dev, fd, vu_evt, cb, pvt);
g_hash_table_replace(dev->fdmap, GINT_TO_POINTER(fd), src);
}
static void
remove_watch(VuDev *vu_dev, int fd)
{
VugDev *dev;
g_assert(vu_dev);
g_assert(fd >= 0);
dev = container_of(vu_dev, VugDev, parent);
g_hash_table_remove(dev->fdmap, GINT_TO_POINTER(fd));
}
static void vug_watch(VuDev *dev, int condition, void *data)
{
if (!vu_dispatch(dev) != 0) {
dev->panic(dev, "Error processing vhost message");
}
}
void vug_source_destroy(GSource *src)
{
if (!src) {
return;
}
g_source_destroy(src);
g_source_unref(src);
}
bool
vug_init(VugDev *dev, uint16_t max_queues, int socket,
vu_panic_cb panic, const VuDevIface *iface)
{
g_assert(dev);
g_assert(iface);
if (!vu_init(&dev->parent, max_queues, socket, panic, NULL, set_watch,
remove_watch, iface)) {
return false;
}
dev->fdmap = g_hash_table_new_full(NULL, NULL, NULL,
(GDestroyNotify) vug_source_destroy);
dev->src = vug_source_new(dev, socket, G_IO_IN, vug_watch, NULL);
return true;
}
void
vug_deinit(VugDev *dev)
{
g_assert(dev);
g_hash_table_unref(dev->fdmap);
vug_source_destroy(dev->src);
}