@@ -1752,7 +1752,7 @@ int gdbserver_start(const char *device)
sigaction(SIGINT, &act, NULL);
}
#endif
- chr = qemu_chr_new("gdb", device, NULL);
+ chr = qemu_chr_new_noreplay("gdb", device, NULL);
if (!chr)
return -1;
@@ -86,6 +86,7 @@ struct CharDriverState {
int is_mux;
guint fd_in_tag;
QemuOpts *opts;
+ bool replay;
QTAILQ_ENTRY(CharDriverState) next;
};
@@ -129,6 +130,22 @@ CharDriverState *qemu_chr_new(const char *label, const char *filename,
void (*init)(struct CharDriverState *s));
/**
+ * @qemu_chr_new_noreplay:
+ *
+ * Create a new character backend from a URI.
+ * Character device communications are not written
+ * into the replay log.
+ *
+ * @label the name of the backend
+ * @filename the URI
+ * @init not sure..
+ *
+ * Returns: a new character backend
+ */
+CharDriverState *qemu_chr_new_noreplay(const char *label, const char *filename,
+ void (*init)(struct CharDriverState *s));
+
+/**
* @qemu_chr_delete:
*
* Destroy a character backend and remove it from the list of
@@ -331,6 +348,15 @@ int qemu_chr_be_can_write(CharDriverState *s);
*/
void qemu_chr_be_write(CharDriverState *s, uint8_t *buf, int len);
+/**
+ * @qemu_chr_be_write_impl:
+ *
+ * Implementation of back end writing. Used by replay module.
+ *
+ * @buf a buffer to receive data from the front end
+ * @len the number of bytes to receive from the front end
+ */
+void qemu_chr_be_write_impl(CharDriverState *s, uint8_t *buf, int len);
/**
* @qemu_chr_be_event:
@@ -117,4 +117,16 @@ void replay_input_event(QemuConsole *src, InputEvent *evt);
/*! Adds input sync event to the queue */
void replay_input_sync_event(void);
+/* Character device */
+
+/*! Registers char driver to save it's events */
+void replay_register_char_driver(struct CharDriverState *chr);
+/*! Saves write to char device event to the log */
+void replay_chr_be_write(struct CharDriverState *s, uint8_t *buf, int len);
+
+/* Other data */
+
+/*! Writes or reads integer value to/from replay log. */
+void replay_data_int(int *data);
+
#endif
@@ -37,6 +37,7 @@
#include "io/channel-socket.h"
#include "io/channel-file.h"
#include "io/channel-tls.h"
+#include "sysemu/replay.h"
#include <zlib.h>
@@ -245,6 +246,9 @@ int qemu_chr_fe_write(CharDriverState *s, const uint8_t *buf, int len)
qemu_chr_fe_write_log(s, buf, ret);
}
+ if (s->replay) {
+ replay_data_int(&ret);
+ }
qemu_mutex_unlock(&s->chr_write_lock);
return ret;
}
@@ -318,9 +322,19 @@ int qemu_chr_fe_read_all(CharDriverState *s, uint8_t *buf, int len)
int qemu_chr_fe_ioctl(CharDriverState *s, int cmd, void *arg)
{
- if (!s->chr_ioctl)
- return -ENOTSUP;
- return s->chr_ioctl(s, cmd, arg);
+ int res;
+ if (!s->chr_ioctl) {
+ res = -ENOTSUP;
+ } else {
+ res = s->chr_ioctl(s, cmd, arg);
+ if (s->replay) {
+ fprintf(stderr,
+ "Replay: ioctl is not supported for serial devices yet\n");
+ exit(1);
+ }
+ }
+
+ return res;
}
int qemu_chr_be_can_write(CharDriverState *s)
@@ -330,17 +344,35 @@ int qemu_chr_be_can_write(CharDriverState *s)
return s->chr_can_read(s->handler_opaque);
}
-void qemu_chr_be_write(CharDriverState *s, uint8_t *buf, int len)
+void qemu_chr_be_write_impl(CharDriverState *s, uint8_t *buf, int len)
{
if (s->chr_read) {
s->chr_read(s->handler_opaque, buf, len);
}
}
+void qemu_chr_be_write(CharDriverState *s, uint8_t *buf, int len)
+{
+ if (s->replay) {
+ if (replay_mode == REPLAY_MODE_PLAY) {
+ return;
+ }
+ replay_chr_be_write(s, buf, len);
+ } else {
+ qemu_chr_be_write_impl(s, buf, len);
+ }
+}
+
int qemu_chr_fe_get_msgfd(CharDriverState *s)
{
int fd;
- return (qemu_chr_fe_get_msgfds(s, &fd, 1) == 1) ? fd : -1;
+ int res = (qemu_chr_fe_get_msgfds(s, &fd, 1) == 1) ? fd : -1;
+ if (s->replay) {
+ fprintf(stderr,
+ "Replay: get msgfd is not supported for serial devices yet\n");
+ exit(1);
+ }
+ return res;
}
int qemu_chr_fe_get_msgfds(CharDriverState *s, int *fds, int len)
@@ -3834,7 +3866,8 @@ err:
return NULL;
}
-CharDriverState *qemu_chr_new(const char *label, const char *filename, void (*init)(struct CharDriverState *s))
+CharDriverState *qemu_chr_new_noreplay(const char *label, const char *filename,
+ void (*init)(struct CharDriverState *s))
{
const char *p;
CharDriverState *chr;
@@ -3860,6 +3893,17 @@ CharDriverState *qemu_chr_new(const char *label, const char *filename, void (*in
return chr;
}
+CharDriverState *qemu_chr_new(const char *label, const char *filename, void (*init)(struct CharDriverState *s))
+{
+ CharDriverState *chr;
+ chr = qemu_chr_new_noreplay(label, filename, init);
+ if (chr) {
+ chr->replay = replay_mode != REPLAY_MODE_NONE;
+ replay_register_char_driver(chr);
+ }
+ return chr;
+}
+
void qemu_chr_fe_set_echo(struct CharDriverState *chr, bool echo)
{
if (chr->chr_set_echo) {
@@ -3,3 +3,4 @@ common-obj-y += replay-internal.o
common-obj-y += replay-events.o
common-obj-y += replay-time.o
common-obj-y += replay-input.o
+common-obj-y += replay-char.o
new file mode 100755
@@ -0,0 +1,97 @@
+/*
+ * replay-char.c
+ *
+ * Copyright (c) 2010-2016 Institute for System Programming
+ * of the Russian Academy of Sciences.
+ *
+ * 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 <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "sysemu/replay.h"
+#include "replay-internal.h"
+#include "sysemu/sysemu.h"
+#include "sysemu/char.h"
+
+/* Char drivers that generate qemu_chr_be_write events
+ that should be saved into the log. */
+static CharDriverState **char_drivers;
+static int drivers_count;
+
+/* Char event attributes. */
+typedef struct CharEvent {
+ int id;
+ uint8_t *buf;
+ size_t len;
+} CharEvent;
+
+static int find_char_driver(CharDriverState *chr)
+{
+ int i = 0;
+ for ( ; i < drivers_count ; ++i) {
+ if (char_drivers[i] == chr) {
+ return i;
+ }
+ }
+ return -1;
+}
+
+void replay_register_char_driver(CharDriverState *chr)
+{
+ if (replay_mode == REPLAY_MODE_NONE) {
+ return;
+ }
+ char_drivers = g_realloc(char_drivers,
+ sizeof(*char_drivers) * (drivers_count + 1));
+ char_drivers[drivers_count++] = chr;
+}
+
+void replay_chr_be_write(CharDriverState *s, uint8_t *buf, int len)
+{
+ CharEvent *event = g_malloc0(sizeof(CharEvent));
+
+ event->id = find_char_driver(s);
+ if (event->id < 0) {
+ fprintf(stderr, "Replay: cannot find char driver\n");
+ exit(1);
+ }
+ event->buf = g_malloc(len);
+ memcpy(event->buf, buf, len);
+ event->len = len;
+
+ replay_add_event(REPLAY_ASYNC_EVENT_CHAR, event, NULL, 0);
+}
+
+void replay_event_char_run(void *opaque)
+{
+ CharEvent *event = (CharEvent *)opaque;
+
+ qemu_chr_be_write_impl(char_drivers[event->id], event->buf,
+ (int)event->len);
+
+ g_free(event->buf);
+ g_free(event);
+}
+
+void replay_event_char_save(void *opaque)
+{
+ CharEvent *event = (CharEvent *)opaque;
+
+ replay_put_byte(event->id);
+ replay_put_array(event->buf, event->len);
+}
+
+void *replay_event_char_read(void)
+{
+ CharEvent *event = g_malloc0(sizeof(CharEvent));
+
+ event->id = replay_get_byte();
+ replay_get_array_alloc(&event->buf, &event->len);
+
+ return event;
+}
@@ -48,6 +48,9 @@ static void replay_run_event(Event *event)
case REPLAY_ASYNC_EVENT_INPUT_SYNC:
qemu_input_event_sync_impl();
break;
+ case REPLAY_ASYNC_EVENT_CHAR:
+ replay_event_char_run(event->opaque);
+ break;
default:
error_report("Replay: invalid async event ID (%d) in the queue",
event->event_kind);
@@ -102,9 +105,9 @@ void replay_clear_events(void)
}
/*! Adds specified async event to the queue */
-static void replay_add_event(ReplayAsyncEventKind event_kind,
- void *opaque,
- void *opaque2, uint64_t id)
+void replay_add_event(ReplayAsyncEventKind event_kind,
+ void *opaque,
+ void *opaque2, uint64_t id)
{
assert(event_kind < REPLAY_ASYNC_COUNT);
@@ -168,6 +171,9 @@ static void replay_save_event(Event *event, int checkpoint)
break;
case REPLAY_ASYNC_EVENT_INPUT_SYNC:
break;
+ case REPLAY_ASYNC_EVENT_CHAR:
+ replay_event_char_save(event->opaque);
+ break;
default:
error_report("Unknown ID %d of replay event", read_event_kind);
exit(1);
@@ -221,6 +227,11 @@ static Event *replay_read_event(int checkpoint)
event->event_kind = read_event_kind;
event->opaque = 0;
return event;
+ case REPLAY_ASYNC_EVENT_CHAR:
+ event = g_malloc0(sizeof(Event));
+ event->event_kind = read_event_kind;
+ event->opaque = replay_event_char_read();
+ return event;
default:
error_report("Unknown ID %d of replay event", read_event_kind);
exit(1);
@@ -25,6 +25,8 @@ enum ReplayEvents {
EVENT_ASYNC,
/* for shutdown request */
EVENT_SHUTDOWN,
+ /* for int data */
+ EVENT_DATA_INT,
/* for clock read/writes */
/* some of greater codes are reserved for clocks */
EVENT_CLOCK,
@@ -44,6 +46,7 @@ enum ReplayAsyncEventKind {
REPLAY_ASYNC_EVENT_BH,
REPLAY_ASYNC_EVENT_INPUT,
REPLAY_ASYNC_EVENT_INPUT_SYNC,
+ REPLAY_ASYNC_EVENT_CHAR,
REPLAY_ASYNC_COUNT
};
@@ -125,6 +128,9 @@ bool replay_has_events(void);
void replay_save_events(int checkpoint);
/*! Read events from the file into the input queue */
void replay_read_events(int checkpoint);
+/*! Adds specified async event to the queue */
+void replay_add_event(ReplayAsyncEventKind event_kind, void *opaque,
+ void *opaque2, uint64_t id);
/* Input events */
@@ -137,4 +143,13 @@ void replay_add_input_event(struct InputEvent *event);
/*! Adds input sync event to the queue */
void replay_add_input_sync_event(void);
+/* Character devices */
+
+/*! Called to run char device event. */
+void replay_event_char_run(void *opaque);
+/*! Writes char event to the file. */
+void replay_event_char_save(void *opaque);
+/*! Reads char event from the file. */
+void *replay_event_char_read(void);
+
#endif
@@ -20,7 +20,7 @@
/* Current version of the replay mechanism.
Increase it when file format changes. */
-#define REPLAY_VERSION 0xe02002
+#define REPLAY_VERSION 0xe02003
/* Size of replay log header */
#define HEADER_SIZE (sizeof(uint32_t) + sizeof(uint64_t))
@@ -340,3 +340,26 @@ void replay_add_blocker(Error *reason)
{
replay_blockers = g_slist_prepend(replay_blockers, reason);
}
+
+void replay_data_int(int *data)
+{
+ if (replay_mode == REPLAY_MODE_PLAY) {
+ replay_account_executed_instructions();
+ replay_mutex_lock();
+ if (replay_next_event_is(EVENT_DATA_INT)) {
+ *data = replay_get_dword();
+ replay_finish_event();
+ replay_mutex_unlock();
+ } else {
+ replay_mutex_unlock();
+ error_report("Missing data int event in the replay log");
+ exit(1);
+ }
+ } else if (replay_mode == REPLAY_MODE_RECORD) {
+ replay_save_instructions();
+ replay_mutex_lock();
+ replay_put_event(EVENT_DATA_INT);
+ replay_put_dword(*data);
+ replay_mutex_unlock();
+ }
+}
This patch implements record and replay of character devices. It records chardevs communication in replay mode. Recorded information include data read from backend and counter of bytes written from frontend to backend to preserve frontend internal state. If character device was configured through the command line in record mode, then in replay mode it should be also added to command line. Backend of the character device could be changed in replay mode. Replaying of devices that perform ioctl and get_msgfd operations is not supported. gdbstub which also acts as a backend is not recorded to allow controlling the replaying through gdb. Signed-off-by: Pavel Dovgalyuk <pavel.dovgaluk@ispras.ru> --- gdbstub.c | 2 - include/sysemu/char.h | 26 ++++++++++++ include/sysemu/replay.h | 12 ++++++ qemu-char.c | 56 ++++++++++++++++++++++++--- replay/Makefile.objs | 1 replay/replay-char.c | 97 ++++++++++++++++++++++++++++++++++++++++++++++ replay/replay-events.c | 17 +++++++- replay/replay-internal.h | 15 +++++++ replay/replay.c | 25 +++++++++++- 9 files changed, 240 insertions(+), 11 deletions(-) create mode 100755 replay/replay-char.c