From 0b07947750205e5329b4805072834a86df1b72ed Mon Sep 17 00:00:00 2001
From: Federico Simoncelli <fsimonce@redhat.com>
Date: Fri, 23 Mar 2012 12:12:47 -0300
Subject: [RHEL6 qemu-kvm PATCH 2/9] qapi: Convert blockdev_snapshot_sync
RH-Author: Federico Simoncelli <fsimonce@redhat.com>
Message-id: <1332504778-17403-3-git-send-email-fsimonce@redhat.com>
Patchwork-id: 38951
O-Subject: [RHEL6.3 qemu-kvm PATCH v6 02/13] qapi: Convert blockdev_snapshot_sync
Bugzilla: 802284
RH-Acked-by: Jeffrey Cody <jcody@redhat.com>
RH-Acked-by: Kevin Wolf <kwolf@redhat.com>
RH-Acked-by: Laszlo Ersek <lersek@redhat.com>
From: Luiz Capitulino <lcapitulino@redhat.com>
Unfortunately, this conversion required an additional change.
In the old QMP command, the 'snapshot-file' argument is specified as
optional. The idea is to take the snapshot internally if 'snapshot-file'
is not passed. However, internal snapshots are not supported yet so
the command returns a MissingParamater error if 'snapshot-file' is not
passed. Which makes the argument actually required and will cause
compatibility breakage if we change that in the future.
To fix this the QAPI converted blockdev_snapshot_sync command makes the
'snapshot-file' argument required. Again, in practice it's actually required,
so this is not incompatible.
If we do implement internal snapshots someday, we'll need a new argument
for it.
Note that this discussion doesn't affect HMP.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
BZ: 802284
(cherry picked from 6106e2492fe0080ad85d4862dec9c3bebc57b2f0)
RHEL6 notes: hmp.c and hmp.h were added taking bits from 48a32be (qapi:
convert query-name) and 0cfd6a9 (qapi: Convert memsave).
Both patches had several dependencies and it wasn't
possible to backport them completely.
Signed-off-by: Federico Simoncelli <fsimonce@redhat.com>
---
Makefile.objs | 1 +
blockdev.c | 54 +++++++++++++++++++-----------------------------------
hmp.c | 44 ++++++++++++++++++++++++++++++++++++++++++++
hmp.h | 25 +++++++++++++++++++++++++
monitor.c | 1 +
qapi-schema.json | 29 +++++++++++++++++++++++++++++
qemu-monitor.hx | 6 +++---
7 files changed, 122 insertions(+), 38 deletions(-)
create mode 100644 hmp.c
create mode 100644 hmp.h
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
---
Makefile.objs | 1 +
blockdev.c | 54 +++++++++++++++++++-----------------------------------
hmp.c | 44 ++++++++++++++++++++++++++++++++++++++++++++
hmp.h | 25 +++++++++++++++++++++++++
monitor.c | 1 +
qapi-schema.json | 29 +++++++++++++++++++++++++++++
qemu-monitor.hx | 6 +++---
7 files changed, 122 insertions(+), 38 deletions(-)
create mode 100644 hmp.c
create mode 100644 hmp.h
diff --git a/Makefile.objs b/Makefile.objs
index d21d747..4d35939 100644
--- a/Makefile.objs
+++ b/Makefile.objs
@@ -204,6 +204,7 @@ endif
qapi-obj-y = $(addprefix qapi/, $(qapi-nested-y))
common-obj-y += $(qapi-obj-y) $(qapi-generated-y)
+common-obj-y += hmp.o
######################################################################
# guest agent
diff --git a/blockdev.c b/blockdev.c
index 12ef6f5..130c23e 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -631,33 +631,24 @@ void do_commit(Monitor *mon, const QDict *qdict)
}
#ifdef CONFIG_LIVE_SNAPSHOTS
-int do_snapshot_blkdev(Monitor *mon, const QDict *qdict, QObject **ret_data)
+void qmp_blockdev_snapshot_sync(const char *device, const char *snapshot_file,
+ bool has_format, const char *format,
+ Error **errp)
{
- const char *device = qdict_get_str(qdict, "device");
- const char *filename = qdict_get_try_str(qdict, "snapshot-file");
- const char *format = qdict_get_try_str(qdict, "format");
BlockDriverState *bs;
BlockDriver *drv, *old_drv, *proto_drv;
int ret = 0;
int flags;
char old_filename[1024];
- if (!filename) {
- qerror_report(QERR_MISSING_PARAMETER, "snapshot-file");
- ret = -1;
- goto out;
- }
-
bs = bdrv_find(device);
if (!bs) {
- qerror_report(QERR_DEVICE_NOT_FOUND, device);
- ret = -1;
- goto out;
+ error_set(errp, QERR_DEVICE_NOT_FOUND, device);
+ return;
}
if (bdrv_in_use(bs)) {
- qerror_report(QERR_DEVICE_IN_USE, device);
- ret = -1;
- goto out;
+ error_set(errp, QERR_DEVICE_IN_USE, device);
+ return;
}
pstrcpy(old_filename, sizeof(old_filename), bs->filename);
@@ -665,35 +656,34 @@ int do_snapshot_blkdev(Monitor *mon, const QDict *qdict, QObject **ret_data)
old_drv = bs->drv;
flags = bs->open_flags;
- if (!format) {
+ if (!has_format) {
format = "qcow2";
}
drv = bdrv_find_format(format);
if (!drv) {
- qerror_report(QERR_INVALID_BLOCK_FORMAT, format);
- ret = -1;
- goto out;
+ error_set(errp, QERR_INVALID_BLOCK_FORMAT, format);
+ return;
}
- proto_drv = bdrv_find_protocol(filename);
+ proto_drv = bdrv_find_protocol(snapshot_file);
if (!proto_drv) {
- qerror_report(QERR_INVALID_BLOCK_FORMAT, format);
- ret = -1;
- goto out;
+ error_set(errp, QERR_INVALID_BLOCK_FORMAT, format);
+ return;
}
- ret = bdrv_img_create(filename, format, bs->filename,
+ ret = bdrv_img_create(snapshot_file, format, bs->filename,
bs->drv->format_name, NULL, -1, flags);
if (ret) {
- goto out;
+ error_set(errp, QERR_UNDEFINED_ERROR);
+ return;
}
bdrv_drain_all();
bdrv_flush(bs);
bdrv_close(bs);
- ret = bdrv_open(bs, filename, flags, drv);
+ ret = bdrv_open(bs, snapshot_file, flags, drv);
/*
* If reopening the image file we just created fails, fall back
* and try to re-open the original image. If that fails too, we
@@ -702,17 +692,11 @@ int do_snapshot_blkdev(Monitor *mon, const QDict *qdict, QObject **ret_data)
if (ret != 0) {
ret = bdrv_open(bs, old_filename, flags, old_drv);
if (ret != 0) {
- qerror_report(QERR_OPEN_FILE_FAILED, old_filename);
+ error_set(errp, QERR_OPEN_FILE_FAILED, old_filename);
} else {
- qerror_report(QERR_OPEN_FILE_FAILED, filename);
+ error_set(errp, QERR_OPEN_FILE_FAILED, snapshot_file);
}
}
-out:
- if (ret) {
- ret = -1;
- }
-
- return ret;
}
#endif
diff --git a/hmp.c b/hmp.c
new file mode 100644
index 0000000..dccd5ff
--- /dev/null
+++ b/hmp.c
@@ -0,0 +1,44 @@
+/*
+ * Human Monitor Interface
+ *
+ * Copyright IBM, Corp. 2011
+ *
+ * Authors:
+ * Anthony Liguori <aliguori@us.ibm.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2. See
+ * the COPYING file in the top-level directory.
+ *
+ */
+
+#include "hmp.h"
+#include "qmp-commands.h"
+
+#ifdef CONFIG_LIVE_SNAPSHOTS
+static void hmp_handle_error(Monitor *mon, Error **errp)
+{
+ if (error_is_set(errp)) {
+ monitor_printf(mon, "%s\n", error_get_pretty(*errp));
+ error_free(*errp);
+ }
+}
+
+void hmp_snapshot_blkdev(Monitor *mon, const QDict *qdict)
+{
+ const char *device = qdict_get_str(qdict, "device");
+ const char *filename = qdict_get_try_str(qdict, "snapshot-file");
+ const char *format = qdict_get_try_str(qdict, "format");
+ Error *errp = NULL;
+
+ if (!filename) {
+ /* In the future, if 'snapshot-file' is not specified, the snapshot
+ will be taken internally. Today it's actually required. */
+ error_set(&errp, QERR_MISSING_PARAMETER, "snapshot-file");
+ hmp_handle_error(mon, &errp);
+ return;
+ }
+
+ qmp_blockdev_snapshot_sync(device, filename, !!format, format, &errp);
+ hmp_handle_error(mon, &errp);
+}
+#endif
diff --git a/hmp.h b/hmp.h
new file mode 100644
index 0000000..3f5643b
--- /dev/null
+++ b/hmp.h
@@ -0,0 +1,25 @@
+/*
+ * Human Monitor Interface
+ *
+ * Copyright IBM, Corp. 2011
+ *
+ * Authors:
+ * Anthony Liguori <aliguori@us.ibm.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2. See
+ * the COPYING file in the top-level directory.
+ *
+ */
+
+#ifndef HMP_H
+#define HMP_H
+
+#include "qemu-common.h"
+
+#ifdef CONFIG_LIVE_SNAPSHOTS
+#include "rhev-qapi-types.h"
+
+void hmp_snapshot_blkdev(Monitor *mon, const QDict *qdict);
+#endif
+
+#endif
diff --git a/monitor.c b/monitor.c
index e73dce7..f81698c 100644
--- a/monitor.c
+++ b/monitor.c
@@ -63,6 +63,7 @@
#include "qemu-kvm.h"
#include "ui/qemu-spice.h"
#include "qmp-commands.h"
+#include "hmp.h"
//#define DEBUG
//#define DEBUG_COMPLETION
diff --git a/qapi-schema.json b/qapi-schema.json
index 5fb482a..59edf0e 100644
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -40,4 +40,33 @@
##
{ 'command': 'blockdev-group-snapshot-sync',
'data': { 'devlist': [ 'SnapshotDev' ] } }
+
+##
+# @blockdev-snapshot-sync
+#
+# Generates a synchronous snapshot of a block device.
+#
+# @device: the name of the device to generate the snapshot from.
+#
+# @snapshot-file: the target of the new image. If the file exists, or if it
+# is a device, the snapshot will be created in the existing
+# file/device. If does not exist, a new file will be created.
+#
+# @format: #optional the format of the snapshot image, default is 'qcow2'.
+#
+# Returns: nothing on success
+# If @device is not a valid block device, DeviceNotFound
+# If @snapshot-file can't be opened, OpenFileFailed
+# If @format is invalid, InvalidBlockFormat
+#
+# Notes: One of the last steps taken by this command is to close the current
+# image being used by @device and open the @snapshot-file one. If that
+# fails, the command will try to reopen the original image file. If
+# that also fails OpenFileFailed will be returned and the guest may get
+# unexpected errors.
+#
+# Since 0.14.0
+##
+{ 'command': 'blockdev-snapshot-sync',
+ 'data': { 'device': 'str', 'snapshot-file': 'str', '*format': 'str' } }
#endif
diff --git a/qemu-monitor.hx b/qemu-monitor.hx
index fa9f552..ac032ec 100644
--- a/qemu-monitor.hx
+++ b/qemu-monitor.hx
@@ -1253,7 +1253,7 @@ EQMP
"If format is specified, the snapshot file will\n\t\t\t"
"be created in that format. Otherwise the\n\t\t\t"
"snapshot will be internal! (currently unsupported)",
- .mhandler.cmd_new = do_snapshot_blkdev,
+ .mhandler.cmd = hmp_snapshot_blkdev,
},
#endif
@@ -1527,10 +1527,10 @@ EQMP
#ifdef CONFIG_LIVE_SNAPSHOTS
{
.name = "blockdev-snapshot-sync",
- .args_type = "device:B,snapshot-file:s?,format:s?",
+ .args_type = "device:B,snapshot-file:s,format:s?",
.params = "device [new-image-file] [format]",
.user_print = monitor_user_noop,
- .mhandler.cmd_new = do_snapshot_blkdev,
+ .mhandler.cmd_new = qmp_marshal_input_blockdev_snapshot_sync,
},
#endif
--
1.7.3.2