[Qemu-devel] [RFC PATCH V10 5/7] qemu-char: Add qemu_chr_add_handlers_full() for GMaincontext

[Zhang Chen <zhangchen.fnst@cn.fujitsu.com>]

Add qemu_chr_add_handlers_full() API, we can use
this API pass in a GMainContext,make handler run
in the context rather than main_loop.
This comments from Daniel P . Berrange.

Cc: Daniel P . Berrange <berrange@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>

Signed-off-by: Zhang Chen <zhangchen.fnst@cn.fujitsu.com>
Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
---
 include/sysemu/char.h |  11 ++++-
 qemu-char.c           | 117 +++++++++++++++++++++++++++++++-------------------
 2 files changed, 83 insertions(+), 45 deletions(-)

diff --git a/include/sysemu/char.h b/include/sysemu/char.h
index 307fd8f..86888bc 100644
--- a/include/sysemu/char.h
+++ b/include/sysemu/char.h
@@ -65,7 +65,8 @@ struct CharDriverState {
     int (*chr_sync_read)(struct CharDriverState *s,
                          const uint8_t *buf, int len);
     GSource *(*chr_add_watch)(struct CharDriverState *s, GIOCondition cond);
-    void (*chr_update_read_handler)(struct CharDriverState *s);
+    void (*chr_update_read_handler_full)(struct CharDriverState *s,
+                                         GMainContext *context);
     int (*chr_ioctl)(struct CharDriverState *s, int cmd, void *arg);
     int (*get_msgfds)(struct CharDriverState *s, int* fds, int num);
     int (*set_msgfds)(struct CharDriverState *s, int *fds, int num);
@@ -388,6 +389,14 @@ void qemu_chr_add_handlers(CharDriverState *s,
                            IOEventHandler *fd_event,
                            void *opaque);
 
+/* This API can make handler run in the context what you pass to. */
+void qemu_chr_add_handlers_full(CharDriverState *s,
+                                IOCanReadHandler *fd_can_read,
+                                IOReadHandler *fd_read,
+                                IOEventHandler *fd_event,
+                                void *opaque,
+                                GMainContext *context);
+
 void qemu_chr_be_generic_open(CharDriverState *s);
 void qemu_chr_accept_input(CharDriverState *s);
 int qemu_chr_add_client(CharDriverState *s, int fd);
diff --git a/qemu-char.c b/qemu-char.c
index b597ee1..18e7d3c 100644
--- a/qemu-char.c
+++ b/qemu-char.c
@@ -448,11 +448,12 @@ void qemu_chr_fe_printf(CharDriverState *s, const char *fmt, ...)
 
 static void remove_fd_in_watch(CharDriverState *chr);
 
-void qemu_chr_add_handlers(CharDriverState *s,
-                           IOCanReadHandler *fd_can_read,
-                           IOReadHandler *fd_read,
-                           IOEventHandler *fd_event,
-                           void *opaque)
+void qemu_chr_add_handlers_full(CharDriverState *s,
+                                IOCanReadHandler *fd_can_read,
+                                IOReadHandler *fd_read,
+                                IOEventHandler *fd_event,
+                                void *opaque,
+                                GMainContext *context)
 {
     int fe_open;
 
@@ -466,8 +467,9 @@ void qemu_chr_add_handlers(CharDriverState *s,
     s->chr_read = fd_read;
     s->chr_event = fd_event;
     s->handler_opaque = opaque;
-    if (fe_open && s->chr_update_read_handler)
-        s->chr_update_read_handler(s);
+    if (fe_open && s->chr_update_read_handler_full) {
+        s->chr_update_read_handler_full(s, context);
+    }
 
     if (!s->explicit_fe_open) {
         qemu_chr_fe_set_open(s, fe_open);
@@ -480,6 +482,16 @@ void qemu_chr_add_handlers(CharDriverState *s,
     }
 }
 
+void qemu_chr_add_handlers(CharDriverState *s,
+                           IOCanReadHandler *fd_can_read,
+                           IOReadHandler *fd_read,
+                           IOEventHandler *fd_event,
+                           void *opaque)
+{
+    qemu_chr_add_handlers_full(s, fd_can_read, fd_read,
+                               fd_event, opaque, NULL);
+}
+
 static int null_chr_write(CharDriverState *chr, const uint8_t *buf, int len)
 {
     return len;
@@ -717,7 +729,8 @@ static void mux_chr_event(void *opaque, int event)
         mux_chr_send_event(d, i, event);
 }
 
-static void mux_chr_update_read_handler(CharDriverState *chr)
+static void mux_chr_update_read_handler_full(CharDriverState *chr,
+                                             GMainContext *context)
 {
     MuxDriver *d = chr->opaque;
 
@@ -731,8 +744,10 @@ static void mux_chr_update_read_handler(CharDriverState *chr)
     d->chr_event[d->mux_cnt] = chr->chr_event;
     /* Fix up the real driver with mux routines */
     if (d->mux_cnt == 0) {
-        qemu_chr_add_handlers(d->drv, mux_chr_can_read, mux_chr_read,
-                              mux_chr_event, chr);
+        qemu_chr_add_handlers_full(d->drv, mux_chr_can_read,
+                                   mux_chr_read,
+                                   mux_chr_event,
+                                   chr, context);
     }
     if (d->focus != -1) {
         mux_chr_send_event(d, d->focus, CHR_EVENT_MUX_OUT);
@@ -813,7 +828,7 @@ static CharDriverState *qemu_chr_open_mux(const char *id,
     d->drv = drv;
     d->focus = -1;
     chr->chr_write = mux_chr_write;
-    chr->chr_update_read_handler = mux_chr_update_read_handler;
+    chr->chr_update_read_handler_full = mux_chr_update_read_handler_full;
     chr->chr_accept_input = mux_chr_accept_input;
     /* Frontend guest-open / -close notification is not support with muxes */
     chr->chr_set_fe_open = NULL;
@@ -840,6 +855,7 @@ typedef struct IOWatchPoll
     IOCanReadHandler *fd_can_read;
     GSourceFunc fd_read;
     void *opaque;
+    GMainContext *context;
 } IOWatchPoll;
 
 static IOWatchPoll *io_watch_poll_from_source(GSource *source)
@@ -847,7 +863,8 @@ static IOWatchPoll *io_watch_poll_from_source(GSource *source)
     return container_of(source, IOWatchPoll, parent);
 }
 
-static gboolean io_watch_poll_prepare(GSource *source, gint *timeout_)
+static gboolean io_watch_poll_prepare_full(GSource *source,
+                                            gint *timeout_)
 {
     IOWatchPoll *iwp = io_watch_poll_from_source(source);
     bool now_active = iwp->fd_can_read(iwp->opaque) > 0;
@@ -860,7 +877,7 @@ static gboolean io_watch_poll_prepare(GSource *source, gint *timeout_)
         iwp->src = qio_channel_create_watch(
             iwp->ioc, G_IO_IN | G_IO_ERR | G_IO_HUP | G_IO_NVAL);
         g_source_set_callback(iwp->src, iwp->fd_read, iwp->opaque, NULL);
-        g_source_attach(iwp->src, NULL);
+        g_source_attach(iwp->src, iwp->context);
     } else {
         g_source_destroy(iwp->src);
         g_source_unref(iwp->src);
@@ -896,30 +913,33 @@ static void io_watch_poll_finalize(GSource *source)
     assert(iwp->src == NULL);
 }
 
-static GSourceFuncs io_watch_poll_funcs = {
-    .prepare = io_watch_poll_prepare,
+static GSourceFuncs io_watch_poll_funcs_full = {
+    .prepare = io_watch_poll_prepare_full,
     .check = io_watch_poll_check,
     .dispatch = io_watch_poll_dispatch,
     .finalize = io_watch_poll_finalize,
 };
 
 /* Can only be used for read */
-static guint io_add_watch_poll(QIOChannel *ioc,
-                               IOCanReadHandler *fd_can_read,
-                               QIOChannelFunc fd_read,
-                               gpointer user_data)
+static guint io_add_watch_poll_full(QIOChannel *ioc,
+                                    IOCanReadHandler *fd_can_read,
+                                    QIOChannelFunc fd_read,
+                                    gpointer user_data,
+                                    GMainContext *context)
 {
     IOWatchPoll *iwp;
     int tag;
 
-    iwp = (IOWatchPoll *) g_source_new(&io_watch_poll_funcs, sizeof(IOWatchPoll));
+    iwp = (IOWatchPoll *) g_source_new(&io_watch_poll_funcs_full,
+                                       sizeof(IOWatchPoll));
     iwp->fd_can_read = fd_can_read;
     iwp->opaque = user_data;
     iwp->ioc = ioc;
     iwp->fd_read = (GSourceFunc) fd_read;
     iwp->src = NULL;
+    iwp->context = context;
 
-    tag = g_source_attach(&iwp->parent, NULL);
+    tag = g_source_attach(&iwp->parent, context);
     g_source_unref(&iwp->parent);
     return tag;
 }
@@ -1051,15 +1071,17 @@ static GSource *fd_chr_add_watch(CharDriverState *chr, GIOCondition cond)
     return qio_channel_create_watch(s->ioc_out, cond);
 }
 
-static void fd_chr_update_read_handler(CharDriverState *chr)
+static void fd_chr_update_read_handler_full(CharDriverState *chr,
+                                            GMainContext *context)
 {
     FDCharDriver *s = chr->opaque;
 
     remove_fd_in_watch(chr);
     if (s->ioc_in) {
-        chr->fd_in_tag = io_add_watch_poll(s->ioc_in,
-                                           fd_chr_read_poll,
-                                           fd_chr_read, chr);
+        chr->fd_in_tag = io_add_watch_poll_full(s->ioc_in,
+                                                fd_chr_read_poll,
+                                                fd_chr_read, chr,
+                                                context);
     }
 }
 
@@ -1098,7 +1120,7 @@ static CharDriverState *qemu_chr_open_fd(int fd_in, int fd_out,
     chr->opaque = s;
     chr->chr_add_watch = fd_chr_add_watch;
     chr->chr_write = fd_chr_write;
-    chr->chr_update_read_handler = fd_chr_update_read_handler;
+    chr->chr_update_read_handler_full = fd_chr_update_read_handler_full;
     chr->chr_close = fd_chr_close;
 
     return chr;
@@ -1303,7 +1325,8 @@ static void pty_chr_update_read_handler_locked(CharDriverState *chr)
     }
 }
 
-static void pty_chr_update_read_handler(CharDriverState *chr)
+static void pty_chr_update_read_handler_full(CharDriverState *chr,
+                                             GMainContext *context)
 {
     qemu_mutex_lock(&chr->chr_write_lock);
     pty_chr_update_read_handler_locked(chr);
@@ -1405,9 +1428,10 @@ static void pty_chr_state(CharDriverState *chr, int connected)
             s->open_tag = g_idle_add(qemu_chr_be_generic_open_func, chr);
         }
         if (!chr->fd_in_tag) {
-            chr->fd_in_tag = io_add_watch_poll(s->ioc,
-                                               pty_chr_read_poll,
-                                               pty_chr_read, chr);
+            chr->fd_in_tag = io_add_watch_poll_full(s->ioc,
+                                                    pty_chr_read_poll,
+                                                    pty_chr_read,
+                                                    chr, NULL);
         }
     }
 }
@@ -1464,7 +1488,7 @@ static CharDriverState *qemu_chr_open_pty(const char *id,
     s = g_new0(PtyCharDriver, 1);
     chr->opaque = s;
     chr->chr_write = pty_chr_write;
-    chr->chr_update_read_handler = pty_chr_update_read_handler;
+    chr->chr_update_read_handler_full = pty_chr_update_read_handler_full;
     chr->chr_close = pty_chr_close;
     chr->chr_add_watch = pty_chr_add_watch;
     chr->explicit_be_open = true;
@@ -2546,15 +2570,17 @@ static gboolean udp_chr_read(QIOChannel *chan, GIOCondition cond, void *opaque)
     return TRUE;
 }
 
-static void udp_chr_update_read_handler(CharDriverState *chr)
+static void udp_chr_update_read_handler_full(CharDriverState *chr,
+                                             GMainContext *context)
 {
     NetCharDriver *s = chr->opaque;
 
     remove_fd_in_watch(chr);
     if (s->ioc) {
-        chr->fd_in_tag = io_add_watch_poll(s->ioc,
-                                           udp_chr_read_poll,
-                                           udp_chr_read, chr);
+        chr->fd_in_tag = io_add_watch_poll_full(s->ioc,
+                                                udp_chr_read_poll,
+                                                udp_chr_read, chr,
+                                                context);
     }
 }
 
@@ -2588,7 +2614,7 @@ static CharDriverState *qemu_chr_open_udp(QIOChannelSocket *sioc,
     s->bufptr = 0;
     chr->opaque = s;
     chr->chr_write = udp_chr_write;
-    chr->chr_update_read_handler = udp_chr_update_read_handler;
+    chr->chr_update_read_handler_full = udp_chr_update_read_handler_full;
     chr->chr_close = udp_chr_close;
     /* be isn't opened until we get a connection */
     chr->explicit_be_open = true;
@@ -2929,14 +2955,16 @@ static void tcp_chr_connect(void *opaque)
 
     s->connected = 1;
     if (s->ioc) {
-        chr->fd_in_tag = io_add_watch_poll(s->ioc,
-                                           tcp_chr_read_poll,
-                                           tcp_chr_read, chr);
+        chr->fd_in_tag = io_add_watch_poll_full(s->ioc,
+                                                tcp_chr_read_poll,
+                                                tcp_chr_read,
+                                                chr, NULL);
     }
     qemu_chr_be_generic_open(chr);
 }
 
-static void tcp_chr_update_read_handler(CharDriverState *chr)
+static void tcp_chr_update_read_handler_full(CharDriverState *chr,
+                                             GMainContext *context)
 {
     TCPCharDriver *s = chr->opaque;
 
@@ -2946,9 +2974,10 @@ static void tcp_chr_update_read_handler(CharDriverState *chr)
 
     remove_fd_in_watch(chr);
     if (s->ioc) {
-        chr->fd_in_tag = io_add_watch_poll(s->ioc,
-                                           tcp_chr_read_poll,
-                                           tcp_chr_read, chr);
+        chr->fd_in_tag = io_add_watch_poll_full(s->ioc,
+                                                tcp_chr_read_poll,
+                                                tcp_chr_read, chr,
+                                                context);
     }
 }
 
@@ -4409,7 +4438,7 @@ static CharDriverState *qmp_chardev_open_socket(const char *id,
     chr->set_msgfds = tcp_set_msgfds;
     chr->chr_add_client = tcp_chr_add_client;
     chr->chr_add_watch = tcp_chr_add_watch;
-    chr->chr_update_read_handler = tcp_chr_update_read_handler;
+    chr->chr_update_read_handler_full = tcp_chr_update_read_handler_full;
     /* be isn't opened until we get a connection */
     chr->explicit_be_open = true;
 
-- 
2.7.4