From df38914e5fad2f4f3e17b6a79b99ff77c123a000 Mon Sep 17 00:00:00 2001 From: Federico Simoncelli Date: Fri, 23 Mar 2012 12:12:57 -0300 Subject: [RHEL6 qemu-kvm PATCH 4/5] add drive-mirror command and HMP equivalent RH-Author: Federico Simoncelli Message-id: <1332504778-17403-13-git-send-email-fsimonce@redhat.com> Patchwork-id: 38955 O-Subject: [RHEL6.3 qemu-kvm PATCH v6 12/13] add drive-mirror command and HMP equivalent Bugzilla: 802284 RH-Acked-by: Kevin Wolf RH-Acked-by: Paolo Bonzini RH-Acked-by: Jeffrey Cody From: Paolo Bonzini Since QMP transactions are supposed to take (pseudo) QMP commands, add a standalone drive-mirror command. The corresponding HMP command does not provide atomic snapshot+mirror, but it can still be used together with image streaming. Signed-off-by: Paolo Bonzini Signed-off-by: Federico Simoncelli BZ: 802284 Based on an patch posted upstream: http://lists.gnu.org/archive/html/qemu-devel/2012-03/msg00902.html Deviations from upstream: - drive-mirror commands renamed with a downstream prefix --- blockdev.c | 15 +++++++++++++++ hmp.c | 28 ++++++++++++++++++++++++++++ hmp.h | 1 + qapi-schema.json | 27 +++++++++++++++++++++++++++ qemu-monitor.hx | 35 +++++++++++++++++++++++++++++++++++ 5 files changed, 106 insertions(+), 0 deletions(-) Signed-off-by: Eduardo Habkost --- blockdev.c | 15 +++++++++++++++ hmp.c | 28 ++++++++++++++++++++++++++++ hmp.h | 1 + qapi-schema.json | 27 +++++++++++++++++++++++++++ qemu-monitor.hx | 35 +++++++++++++++++++++++++++++++++++ 5 files changed, 106 insertions(+), 0 deletions(-) diff --git a/blockdev.c b/blockdev.c index bdbb5a1..b96d846 100644 --- a/blockdev.c +++ b/blockdev.c @@ -662,6 +662,21 @@ void qmp_blockdev_snapshot_sync(const char *device, const char *snapshot_file, #endif #ifdef CONFIG_LIVE_SNAPSHOTS +void qmp___com_redhat_drive_mirror(const char *device, const char *target, + bool has_format, const char *format, + bool has_mode, enum NewImageMode mode, Error **errp) +{ + BlockdevMirror mirror = { + .device = (char *) device, + .target = (char *) target, + .has_format = has_format, + .format = (char *) format, + .has_mode = has_mode, + .mode = mode, + }; + blockdev_do_action(BLOCKDEV_ACTION_KIND___COM_REDHAT_DRIVE_MIRROR, &mirror, errp); +} + /* New and old BlockDriverState structs for group snapshots */ typedef struct BlkTransactionStates { BlockDriverState *old_bs; diff --git a/hmp.c b/hmp.c index 7391a9a..812e364 100644 --- a/hmp.c +++ b/hmp.c @@ -23,6 +23,34 @@ static void hmp_handle_error(Monitor *mon, Error **errp) } } +void hmp_drive_mirror(Monitor *mon, const QDict *qdict) +{ + const char *device = qdict_get_str(qdict, "device"); + const char *filename = qdict_get_try_str(qdict, "target"); + const char *format = qdict_get_try_str(qdict, "format"); + int reuse = qdict_get_try_bool(qdict, "reuse", 0); + int no_backing = qdict_get_try_bool(qdict, "no-backing", 0); + enum NewImageMode mode; + Error *errp = NULL; + + if (!filename) { + error_set(&errp, QERR_MISSING_PARAMETER, "target"); + hmp_handle_error(mon, &errp); + return; + } + + if (reuse) { + mode = NEW_IMAGE_MODE_EXISTING; + } else if (no_backing) { + mode = NEW_IMAGE_MODE_NO_BACKING_FILE; + } else { + mode = NEW_IMAGE_MODE_ABSOLUTE_PATHS; + } + + qmp___com_redhat_drive_mirror(device, filename, !!format, format, true, mode, &errp); + hmp_handle_error(mon, &errp); +} + void hmp_snapshot_blkdev(Monitor *mon, const QDict *qdict) { const char *device = qdict_get_str(qdict, "device"); diff --git a/hmp.h b/hmp.h index 3f5643b..7c4cae4 100644 --- a/hmp.h +++ b/hmp.h @@ -20,6 +20,7 @@ #include "rhev-qapi-types.h" void hmp_snapshot_blkdev(Monitor *mon, const QDict *qdict); +void hmp_drive_mirror(Monitor *mon, const QDict *qdict); #endif #endif diff --git a/qapi-schema.json b/qapi-schema.json index 24f6b99..0a50b0d 100644 --- a/qapi-schema.json +++ b/qapi-schema.json @@ -119,4 +119,31 @@ { 'command': 'blockdev-snapshot-sync', 'data': { 'device': 'str', 'snapshot-file': 'str', '*format': 'str', '*mode': 'NewImageMode'} } + +## +# @__com.redhat_drive-mirror +# +# Start mirroring a block device's writes to a new destination. +# +# @device: the name of the device whose writes should be mirrored. +# +# @target: the target of the new image. If the file exists, or if it +# is a device, the existing file/device will be used as the new +# destination. If it does not exist, a new file will be created. +# +# @format: #optional the format of the new destination, default is 'qcow2'. +# +# @mode: #optional whether and how QEMU should create a new image, default is +# 'absolute-paths'. +# +# Returns: nothing on success +# If @device is not a valid block device, DeviceNotFound +# If @target can't be opened, OpenFileFailed +# If @format is invalid, InvalidBlockFormat +# +# Since 1.1 +## +{ 'command': '__com.redhat_drive-mirror', + 'data': { 'device': 'str', 'target': 'str', '*format': 'str', + '*mode': 'NewImageMode'} } #endif diff --git a/qemu-monitor.hx b/qemu-monitor.hx index b492bce..4c5b9c3 100644 --- a/qemu-monitor.hx +++ b/qemu-monitor.hx @@ -1589,6 +1589,41 @@ Example: EQMP +#ifdef CONFIG_LIVE_SNAPSHOTS + { + .name = "__com.redhat_drive-mirror", + .args_type = "device:B,snapshot-file:s,mode:s?,format:s?", + .mhandler.cmd_new = qmp_marshal_input___com_redhat_drive_mirror, + }, +#endif + +SQMP +__com.redhat_drive-mirror +------------------------- + +Start mirroring a block device's writes to a new destination. target +specifies the target of the new image. If the file exists, or if it is +a device, it will be used as the new destination for writes. If does not +exist, a new file will be created. format specifies the format of the +mirror image, default is qcow2. + +Arguments: + +- "device": device name to operate on (json-string) +- "target": name of new image file (json-string) +- "format": format of new image (json-string, optional) +- "mode": how an image file should be created into the target + file/device (NewImageMode, optional, default 'absolute-paths') + +Example: + +-> { "execute": "__com.redhat_drive-mirror", "arguments": { "device": "ide-hd0", + "target": "/some/place/my-image", + "format": "qcow2" } } +<- { "return": {} } + +EQMP + { .name = "balloon", .args_type = "value:M", -- 1.7.3.2