Make screendump asynchronous to provide correct screendumps. HMP doesn't have async support, so it has to remain synchronous and potentially incorrect to avoid potential races.
Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1230527 Signed-off-by: Marc-André Lureau <marcandre.lur...@redhat.com> --- qapi/ui.json | 3 +- include/ui/console.h | 3 ++ hmp.c | 2 +- ui/console.c | 99 ++++++++++++++++++++++++++++++++++++++++---- 4 files changed, 96 insertions(+), 11 deletions(-) diff --git a/qapi/ui.json b/qapi/ui.json index 5d01ad4304..4d2c326fb9 100644 --- a/qapi/ui.json +++ b/qapi/ui.json @@ -96,7 +96,8 @@ # ## { 'command': 'screendump', - 'data': {'filename': 'str', '*device': 'str', '*head': 'int'} } + 'data': {'filename': 'str', '*device': 'str', '*head': 'int'}, + 'async': true } ## # == Spice diff --git a/include/ui/console.h b/include/ui/console.h index fc21621656..0c02190963 100644 --- a/include/ui/console.h +++ b/include/ui/console.h @@ -74,6 +74,9 @@ struct MouseTransformInfo { }; void hmp_mouse_set(Monitor *mon, const QDict *qdict); +void hmp_screendump_sync(const char *filename, + bool has_device, const char *device, + bool has_head, int64_t head, Error **errp); /* keysym is a unicode code except for special keys (see QEMU_KEY_xxx constants) */ diff --git a/hmp.c b/hmp.c index 679467d85a..da9008fe63 100644 --- a/hmp.c +++ b/hmp.c @@ -2144,7 +2144,7 @@ void hmp_screendump(Monitor *mon, const QDict *qdict) int64_t head = qdict_get_try_int(qdict, "head", 0); Error *err = NULL; - qmp_screendump(filename, id != NULL, id, id != NULL, head, &err); + hmp_screendump_sync(filename, id != NULL, id, id != NULL, head, &err); hmp_handle_error(mon, &err); } diff --git a/ui/console.c b/ui/console.c index 29234605a7..da51861191 100644 --- a/ui/console.c +++ b/ui/console.c @@ -32,6 +32,7 @@ #include "chardev/char-fe.h" #include "trace.h" #include "exec/memory.h" +#include "monitor/monitor.h" #define DEFAULT_BACKSCROLL 512 #define CONSOLE_CURSOR_PERIOD 500 @@ -116,6 +117,12 @@ typedef enum { TEXT_CONSOLE_FIXED_SIZE } console_type_t; +struct qmp_screendump { + gchar *filename; + QmpReturn *ret; + QLIST_ENTRY(qmp_screendump) link; +}; + struct QemuConsole { Object parent; @@ -165,6 +172,8 @@ struct QemuConsole { QEMUFIFO out_fifo; uint8_t out_fifo_buf[16]; QEMUTimer *kbd_timer; + + QLIST_HEAD(, qmp_screendump) qmp_screendumps; }; struct DisplayState { @@ -190,6 +199,8 @@ static void dpy_refresh(DisplayState *s); static DisplayState *get_alloc_displaystate(void); static void text_console_update_cursor_timer(void); static void text_console_update_cursor(void *opaque); +static void ppm_save(const char *filename, DisplaySurface *ds, + Error **errp); static void gui_update(void *opaque) { @@ -256,8 +267,42 @@ static void gui_setup_refresh(DisplayState *ds) ds->have_text = have_text; } +static void qmp_screendump_finish(QemuConsole *con, const char *filename, + QmpReturn *ret) +{ + Error *err = NULL; + DisplaySurface *surface; + Monitor *prev_mon = cur_mon; + + if (qmp_return_is_cancelled(ret)) { + return; + } + + cur_mon = qmp_return_get_monitor(ret); + surface = qemu_console_surface(con); + + /* FIXME: async save with coroutine? it would have to copy or lock + * the surface. */ + ppm_save(filename, surface, &err); + + if (err) { + qmp_return_error(ret, err); + } else { + qmp_screendump_return(ret); + } + cur_mon = prev_mon; +} + void graphic_hw_update_done(QemuConsole *con) { + struct qmp_screendump *dump, *next; + + QLIST_FOREACH_SAFE(dump, &con->qmp_screendumps, link, next) { + qmp_screendump_finish(con, dump->filename, dump->ret); + g_free(dump->filename); + QLIST_REMOVE(dump, link); + g_free(dump); + } } bool graphic_hw_update(QemuConsole *con) @@ -358,35 +403,70 @@ write_err: goto out; } -void qmp_screendump(const char *filename, bool has_device, const char *device, - bool has_head, int64_t head, Error **errp) + +static QemuConsole *get_console(bool has_device, const char *device, + bool has_head, int64_t head, Error **errp) { - QemuConsole *con; - DisplaySurface *surface; + QemuConsole *con = NULL; if (has_device) { con = qemu_console_lookup_by_device_name(device, has_head ? head : 0, errp); - if (!con) { - return; - } } else { if (has_head) { error_setg(errp, "'head' must be specified together with 'device'"); - return; + return NULL; } con = qemu_console_lookup_by_index(0); if (!con) { error_setg(errp, "There is no console to take a screendump from"); - return; } } + return con; +} + +void hmp_screendump_sync(const char *filename, + bool has_device, const char *device, + bool has_head, int64_t head, Error **errp) +{ + DisplaySurface *surface; + QemuConsole *con = get_console(has_device, device, has_head, head, errp); + + if (!con) { + return; + } + /* This may not complete the drawing with Spice, you may have + * glitches or outdated dumps, use qmp instead! */ graphic_hw_update(con); surface = qemu_console_surface(con); ppm_save(filename, surface, errp); } +void qmp_screendump(const char *filename, + bool has_device, const char *device, + bool has_head, int64_t head, + QmpReturn *qret) +{ + Error *err = NULL; + bool async; + QemuConsole *con = get_console(has_device, device, has_head, head, &err); + + if (!con) { + qmp_return_error(qret, err); + return; + } + async = graphic_hw_update(con); + if (async) { + struct qmp_screendump *dump = g_new(struct qmp_screendump, 1); + dump->filename = g_strdup(filename); + dump->ret = qret; + QLIST_INSERT_HEAD(&con->qmp_screendumps, dump, link); + } else { + qmp_screendump_finish(con, filename, qret); + } +} + void graphic_hw_text_update(QemuConsole *con, console_ch_t *chardata) { if (!con) { @@ -1280,6 +1360,7 @@ static QemuConsole *new_console(DisplayState *ds, console_type_t console_type, obj = object_new(TYPE_QEMU_CONSOLE); s = QEMU_CONSOLE(obj); s->head = head; + QLIST_INIT(&s->qmp_screendumps); object_property_add_link(obj, "device", TYPE_DEVICE, (Object **)&s->device, object_property_allow_set_link, -- 2.17.0.rc1.1.g4c4f2b46a3