From f76e4c7f16c7ab966a792310b6630d3e240688b3 Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Sat, 19 Nov 2011 10:22:44 +0100 Subject: [PATCH] spice-qemu-char: Generate chardev open/close events Define a state callback and make that generate chardev open/close events when called by the spice-server. Notes: 1) For all but the newest spice-server versions (which have a fix for this) the code ignores these events for a spicevmc with a subtype of vdagent, this subtype specific knowledge is undesirable, but unavoidable for now, see: http://lists.freedesktop.org/archives/spice-devel/2011-July/004837.html 2) This code deliberately sends the events immediately rather then from a bh. This is done this way because: a) There is no need to do it from a bh; and b) Doing it from a bh actually causes issues because the spice-server may send data immediately after the open and when the open runs from a bh, then qemu_chr_be_can_write will return 0 for the first write which the spice-server does not expect, when this happens the spice-server will never retry the write causing communication to stall. Signed-off-by: Hans de Goede Signed-off-by: Anthony Liguori --- spice-qemu-char.c | 36 +++++++++++++++++++++++++++++++++++- 1 file changed, 35 insertions(+), 1 deletion(-) diff --git a/spice-qemu-char.c b/spice-qemu-char.c index ac522022cc..7e8eaa9fd8 100644 --- a/spice-qemu-char.c +++ b/spice-qemu-char.c @@ -69,11 +69,40 @@ static int vmc_read(SpiceCharDeviceInstance *sin, uint8_t *buf, int len) return bytes; } +static void vmc_state(SpiceCharDeviceInstance *sin, int connected) +{ + SpiceCharDriver *scd = container_of(sin, SpiceCharDriver, sin); + +#if SPICE_SERVER_VERSION < 0x000901 + /* + * spice-server calls the state callback for the agent channel when the + * spice client connects / disconnects. Given that not the client but + * the server is doing the parsing of the messages this is wrong as the + * server is still listening. Worse, this causes the parser in the server + * to go out of sync, so we ignore state calls for subtype vdagent + * spicevmc chardevs. For the full story see: + * http://lists.freedesktop.org/archives/spice-devel/2011-July/004837.html + */ + if (strcmp(sin->subtype, "vdagent") == 0) { + return; + } +#endif + + if ((scd->chr->opened && connected) || + (!scd->chr->opened && !connected)) { + return; + } + + qemu_chr_be_event(scd->chr, + connected ? CHR_EVENT_OPENED : CHR_EVENT_CLOSED); +} + static SpiceCharDeviceInterface vmc_interface = { .base.type = SPICE_INTERFACE_CHAR_DEVICE, .base.description = "spice virtual channel char device", .base.major_version = SPICE_INTERFACE_CHAR_DEVICE_MAJOR, .base.minor_version = SPICE_INTERFACE_CHAR_DEVICE_MINOR, + .state = vmc_state, .write = vmc_write, .read = vmc_read, }; @@ -197,7 +226,12 @@ int qemu_chr_open_spice(QemuOpts *opts, CharDriverState **_chr) chr->chr_guest_open = spice_chr_guest_open; chr->chr_guest_close = spice_chr_guest_close; - qemu_chr_generic_open(chr); +#if SPICE_SERVER_VERSION < 0x000901 + /* See comment in vmc_state() */ + if (strcmp(subtype, "vdagent") == 0) { + qemu_chr_generic_open(chr); + } +#endif *_chr = chr; return 0;