File snapshot-ioemu-save.patch of Package xen
Index: xen-3.3.1-testing/tools/ioemu-remote/block.h
===================================================================
--- xen-3.3.1-testing.orig/tools/ioemu-remote/block.h
+++ xen-3.3.1-testing/tools/ioemu-remote/block.h
@@ -103,6 +103,7 @@ int qemu_key_check(BlockDriverState *bs,
/* Ensure contents are flushed to disk. */
int bdrv_flush(BlockDriverState *bs);
+int bdrv_flush_all(void);
#define BDRV_TYPE_HD 0
#define BDRV_TYPE_CDROM 1
Index: xen-3.3.1-testing/tools/ioemu-remote/block.c
===================================================================
--- xen-3.3.1-testing.orig/tools/ioemu-remote/block.c
+++ xen-3.3.1-testing/tools/ioemu-remote/block.c
@@ -950,6 +950,21 @@ int bdrv_flush(BlockDriverState *bs)
return ret;
}
+int bdrv_flush_all(void)
+{
+ BlockDriverState *bs;
+ int ret = 0, ret1;
+
+ for (bs = bdrv_first; bs != NULL; bs = bs->next)
+ if (bs->drv && !bdrv_is_read_only(bs) &&
+ (!bdrv_is_removable(bs) || bdrv_is_inserted(bs))) {
+ ret1 = bdrv_flush(bs);
+ if (ret1) ret = ret1;
+ }
+
+ return ret;
+}
+
#ifndef QEMU_IMG
void bdrv_info(void)
{
Index: xen-3.3.1-testing/tools/ioemu-remote/xen-vl-extra.c
===================================================================
--- xen-3.3.1-testing.orig/tools/ioemu-remote/xen-vl-extra.c
+++ xen-3.3.1-testing/tools/ioemu-remote/xen-vl-extra.c
@@ -8,12 +8,18 @@
* there is only one place where this file is included. */
#include "qemu-xen.h"
+#include "block_int.h"
/* forward declarations of things in vl.c */
static int qemu_savevm_state(QEMUFile *f);
static int qemu_loadvm_state(QEMUFile *f);
+static int bdrv_can_snapshot(BlockDriverState *bs);
+static int bdrv_snapshot_find(BlockDriverState *bs, QEMUSnapshotInfo *sn_info,
+ const char *name);
+
+
/* We use simpler state save/load functions for Xen */
void do_savevm(const char *name)
@@ -85,6 +91,86 @@ void do_loadvm(const char *name)
vm_start();
}
+int save_disk_snapshots(const char* name)
+{
+ BlockDriverState *bs;
+ QEMUSnapshotInfo sn, old_sn;
+ struct timeval tv;
+ int saved_vm_running;
+ int can_snapshot;
+ int i;
+ int ret = 0;
+
+ /* Deal with all aio submit */
+ qemu_aio_flush();
+ /* Do fsync at backend fs */
+ ret = bdrv_flush_all();
+ if (ret)
+ fprintf(stderr, "Fsync error[%d] when do snapshot[%s]\n", ret, name);
+
+ saved_vm_running = vm_running;
+ vm_stop(0);
+
+ /* Ensure that all images support snapshots or are read-only */
+ for(i = 0; i < MAX_DRIVES; i++) {
+ bs = drives_table[i].bdrv;
+
+ if (!bs || !bs->drv)
+ continue;
+
+ can_snapshot = bs->drv->bdrv_snapshot_create && bdrv_can_snapshot(bs);
+ if (!bdrv_is_read_only(bs) && !can_snapshot) {
+ fprintf(stderr, "Error: bdrv %s (%s) doesn't support snapshots\n",
+ bdrv_get_device_name(bs), bs->drv->format_name);
+ ret = -ENOTSUP;
+ goto the_end;
+ }
+ }
+
+ /* fill auxiliary fields */
+ memset(&sn, 0, sizeof(sn));
+ gettimeofday(&tv, NULL);
+ sn.date_sec = tv.tv_sec;
+ sn.date_nsec = tv.tv_usec * 1000;
+ sn.vm_clock_nsec = qemu_get_clock(vm_clock);
+ pstrcpy(sn.name, sizeof(sn.name), name);
+
+ for(i = 0; i < MAX_DRIVES; i++) {
+ bs = drives_table[i].bdrv;
+
+ /* No snapshots on read-only images */
+ if (!bs || !bs->drv || bdrv_is_read_only(bs))
+ continue;
+
+ /* Delete old snapshot of the same name */
+ if (bdrv_snapshot_find(bs, &old_sn, name) >= 0) {
+ ret = bdrv_snapshot_delete(bs, old_sn.id_str);
+ if (ret < 0) {
+ fprintf(stderr, "Error while deleting snapshot on '%s'\n",
+ bdrv_get_device_name(bs));
+ }
+ }
+
+ /* Create the snapshot */
+ fprintf(stderr, "Creating snapshot on '%s' (%s)\n",
+ bdrv_get_device_name(bs), bs->drv->format_name);
+ ret = bdrv_snapshot_create(bs, &sn);
+ if (ret < 0) {
+ fprintf(stderr, "Error while creating snapshot on '%s': %d (%s)\n",
+ bdrv_get_device_name(bs), ret, strerror(-ret));
+ goto the_end;
+ }
+ }
+
+ fprintf(stderr, "Created all snapshots\n");
+
+the_end:
+ if (saved_vm_running)
+ vm_start();
+
+ return ret;
+}
+
struct qemu_alarm_timer;
static int unix_start_timer(struct qemu_alarm_timer *t) { return 0; }
static void unix_stop_timer(struct qemu_alarm_timer *t) { }
Index: xen-3.3.1-testing/tools/ioemu-remote/i386-dm/helper2.c
===================================================================
--- xen-3.3.1-testing.orig/tools/ioemu-remote/i386-dm/helper2.c
+++ xen-3.3.1-testing/tools/ioemu-remote/i386-dm/helper2.c
@@ -101,6 +101,9 @@ int send_vcpu = 0;
#define NR_CPUS 32
evtchn_port_t ioreq_local_port[NR_CPUS];
+/** Name of the snapshot which should be saved */
+char* snapshot_name;
+
CPUX86State *cpu_x86_init(const char *cpu_model)
{
CPUX86State *env;
@@ -547,6 +550,7 @@ int main_loop(void)
int evtchn_fd = xce_handle == -1 ? -1 : xc_evtchn_fd(xce_handle);
char *qemu_file;
fd_set fds;
+ int ret;
main_loop_prepare();
@@ -574,11 +578,43 @@ int main_loop(void)
main_loop_wait(1); /* For the select() on events */
/* Save the device state */
- asprintf(&qemu_file, "/var/lib/xen/qemu-save.%d", domid);
- do_savevm(qemu_file);
- free(qemu_file);
+ switch (xen_pause_requested) {
+ case SUSPEND_SAVEVM:
+ asprintf(&qemu_file, "/var/lib/xen/qemu-save.%d", domid);
+ do_savevm(qemu_file);
+ free(qemu_file);
+ xenstore_record_dm_state("paused");
+ break;
+
+ case SUSPEND_SNAPSHOT:
+ if (snapshot_name != NULL) {
+ ret = save_disk_snapshots(snapshot_name);
+ free(snapshot_name);
+ snapshot_name = NULL;
+
+ switch (ret) {
+ case 0:
+ xenstore_record_dm_state("paused");
+ break;
+ case -ENOTSUP:
+ xenstore_record_dm_error("Snapshots not supported on all"
+ " attached read-write disks");
+ break;
+ case -ENOENT:
+ xenstore_record_dm_error("A snapshot with the same name"
+ " already exists");
+ break;
+ default:
+ xenstore_record_dm_error("An error occurred while saving"
+ " the snapshot");
+ break;
+ }
+ } else {
+ xenstore_record_dm_error("No snapshot name given");
+ }
+ break;
+ }
- xenstore_record_dm_state("paused");
/* Wait to be allowed to continue */
while (xen_pause_requested) {
Index: xen-3.3.1-testing/tools/ioemu-remote/qemu-xen.h
===================================================================
--- xen-3.3.1-testing.orig/tools/ioemu-remote/qemu-xen.h
+++ xen-3.3.1-testing/tools/ioemu-remote/qemu-xen.h
@@ -14,6 +14,15 @@ void qemu_invalidate_map_cache(void)
#define mapcache_lock() ((void)0)
#define mapcache_unlock() ((void)0)
+/* Reason for xen_pause_requested */
+enum {
+ SUSPEND_SAVEVM = 1,
+ SUSPEND_SNAPSHOT = 2
+};
+
+/* xen-vl-extra.c */
+int save_disk_snapshots(const char* name);
+
/* helper2.c */
extern long time_offset;
void timeoffset_get(void);
@@ -43,6 +52,7 @@ int xenstore_fd(void);
void xenstore_process_event(void *opaque);
void xenstore_record_dm(char *subpath, char *state);
void xenstore_record_dm_state(char *state);
+void xenstore_record_dm_error(char *errmsg);
void xenstore_check_new_media_present(int timeout);
void xenstore_write_vncport(int vnc_display);
void xenstore_read_vncpasswd(int domid, char *pwbuf, size_t pwbuflen);
Index: xen-3.3.1-testing/tools/ioemu-remote/xenstore.c
===================================================================
--- xen-3.3.1-testing.orig/tools/ioemu-remote/xenstore.c
+++ xen-3.3.1-testing/tools/ioemu-remote/xenstore.c
@@ -24,6 +24,7 @@
#include "exec-all.h"
#include "sysemu.h"
+#include "qemu-xen.h"
#include "hw.h"
#include "pci.h"
@@ -604,6 +605,7 @@ static void xenstore_process_dm_command_
{
char *path = NULL, *command = NULL, *par = NULL;
unsigned int len;
+ extern char* snapshot_name;
if (pasprintf(&path,
"/local/domain/0/device-model/%u/command", domid) == -1) {
@@ -616,7 +618,18 @@ static void xenstore_process_dm_command_
if (!strncmp(command, "save", len)) {
fprintf(logfile, "dm-command: pause and save state\n");
- xen_pause_requested = 1;
+ xen_pause_requested = SUSPEND_SAVEVM;
+ } else if (!strncmp(command, "snapshot", len)) {
+ fprintf(logfile, "dm-command: pause and snapshot disks\n");
+ xen_pause_requested = SUSPEND_SNAPSHOT;
+
+ if (pasprintf(&path,
+ "/local/domain/0/device-model/%u/parameter", domid) == -1) {
+ fprintf(logfile, "out of memory reading dm command parameter\n");
+ goto out;
+ }
+
+ snapshot_name = xs_read(xsh, XBT_NULL, path, &len);
} else if (!strncmp(command, "continue", len)) {
fprintf(logfile, "dm-command: continue after state save\n");
xen_pause_requested = 0;
@@ -680,6 +693,13 @@ void xenstore_record_dm_state(char *stat
xenstore_record_dm("state", state);
}
+void xenstore_record_dm_error(char *errmsg)
+{
+ fprintf(logfile, "%s\n", errmsg);
+ xenstore_record_dm("error", errmsg);
+ xenstore_record_dm_state("error");
+}
+
void xenstore_process_media_change_event(char **vec)
{
char *media_present = NULL;
