From d9b902db3fb71fdcdfbb2aa9cc94a410dee864e5 Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Thu, 18 Oct 2012 16:49:24 +0200 Subject: [PATCH] qmp: add drive-mirror command This adds the monitor commands that start the mirroring job. Signed-off-by: Paolo Bonzini Signed-off-by: Kevin Wolf --- blockdev.c | 124 +++++++++++++++++++++++++++++++++++++++++++++++ hmp-commands.hx | 21 ++++++++ hmp.c | 28 +++++++++++ hmp.h | 1 + qapi-schema.json | 34 +++++++++++++ qmp-commands.hx | 42 ++++++++++++++++ 6 files changed, 250 insertions(+) diff --git a/blockdev.c b/blockdev.c index 248d5f62c0..431c678f8f 100644 --- a/blockdev.c +++ b/blockdev.c @@ -1181,6 +1181,130 @@ void qmp_block_commit(const char *device, drive_get_ref(drive_get_by_blockdev(bs)); } +void qmp_drive_mirror(const char *device, const char *target, + bool has_format, const char *format, + enum MirrorSyncMode sync, + bool has_mode, enum NewImageMode mode, + bool has_speed, int64_t speed, Error **errp) +{ + BlockDriverInfo bdi; + BlockDriverState *bs; + BlockDriverState *source, *target_bs; + BlockDriver *proto_drv; + BlockDriver *drv = NULL; + Error *local_err = NULL; + int flags; + uint64_t size; + int ret; + + if (!has_speed) { + speed = 0; + } + if (!has_mode) { + mode = NEW_IMAGE_MODE_ABSOLUTE_PATHS; + } + + bs = bdrv_find(device); + if (!bs) { + error_set(errp, QERR_DEVICE_NOT_FOUND, device); + return; + } + + if (!bdrv_is_inserted(bs)) { + error_set(errp, QERR_DEVICE_HAS_NO_MEDIUM, device); + return; + } + + if (!has_format) { + format = mode == NEW_IMAGE_MODE_EXISTING ? NULL : bs->drv->format_name; + } + if (format) { + drv = bdrv_find_format(format); + if (!drv) { + error_set(errp, QERR_INVALID_BLOCK_FORMAT, format); + return; + } + } + + if (bdrv_in_use(bs)) { + error_set(errp, QERR_DEVICE_IN_USE, device); + return; + } + + flags = bs->open_flags | BDRV_O_RDWR; + source = bs->backing_hd; + if (!source && sync == MIRROR_SYNC_MODE_TOP) { + sync = MIRROR_SYNC_MODE_FULL; + } + + proto_drv = bdrv_find_protocol(target); + if (!proto_drv) { + error_set(errp, QERR_INVALID_BLOCK_FORMAT, format); + return; + } + + if (sync == MIRROR_SYNC_MODE_FULL && mode != NEW_IMAGE_MODE_EXISTING) { + /* create new image w/o backing file */ + assert(format && drv); + bdrv_get_geometry(bs, &size); + size *= 512; + ret = bdrv_img_create(target, format, + NULL, NULL, NULL, size, flags); + } else { + switch (mode) { + case NEW_IMAGE_MODE_EXISTING: + ret = 0; + break; + case NEW_IMAGE_MODE_ABSOLUTE_PATHS: + /* create new image with backing file */ + ret = bdrv_img_create(target, format, + source->filename, + source->drv->format_name, + NULL, -1, flags); + break; + default: + abort(); + } + } + + if (ret) { + error_set(errp, QERR_OPEN_FILE_FAILED, target); + return; + } + + target_bs = bdrv_new(""); + ret = bdrv_open(target_bs, target, flags | BDRV_O_NO_BACKING, drv); + + if (ret < 0) { + bdrv_delete(target_bs); + error_set(errp, QERR_OPEN_FILE_FAILED, target); + return; + } + + /* We need a backing file if we will copy parts of a cluster. */ + if (bdrv_get_info(target_bs, &bdi) >= 0 && bdi.cluster_size != 0 && + bdi.cluster_size >= BDRV_SECTORS_PER_DIRTY_CHUNK * 512) { + ret = bdrv_open_backing_file(target_bs); + if (ret < 0) { + bdrv_delete(target_bs); + error_set(errp, QERR_OPEN_FILE_FAILED, target); + return; + } + } + + mirror_start(bs, target_bs, speed, sync, block_job_cb, bs, &local_err); + if (local_err != NULL) { + bdrv_delete(target_bs); + error_propagate(errp, local_err); + return; + } + + /* Grab a reference so hotplug does not delete the BlockDriverState from + * underneath us. + */ + drive_get_ref(drive_get_by_blockdev(bs)); +} + static BlockJob *find_block_job(const char *device) { BlockDriverState *bs; diff --git a/hmp-commands.hx b/hmp-commands.hx index fb2f2372c0..f916385c0a 100644 --- a/hmp-commands.hx +++ b/hmp-commands.hx @@ -1001,6 +1001,27 @@ STEXI @item snapshot_blkdev @findex snapshot_blkdev Snapshot device, using snapshot file as target if provided +ETEXI + + { + .name = "drive_mirror", + .args_type = "reuse:-n,full:-f,device:B,target:s,format:s?", + .params = "[-n] [-f] device target [format]", + .help = "initiates live storage\n\t\t\t" + "migration for a device. The device's contents are\n\t\t\t" + "copied to the new image file, including data that\n\t\t\t" + "is written after the command is started.\n\t\t\t" + "The -n flag requests QEMU to reuse the image found\n\t\t\t" + "in new-image-file, instead of recreating it from scratch.\n\t\t\t" + "The -f flag requests QEMU to copy the whole disk,\n\t\t\t" + "so that the result does not need a backing file.\n\t\t\t", + .mhandler.cmd = hmp_drive_mirror, + }, +STEXI +@item drive_mirror +@findex drive_mirror +Start mirroring a block device's writes to a new destination, +using the specified target. ETEXI { diff --git a/hmp.c b/hmp.c index 574517a17f..e53025306a 100644 --- a/hmp.c +++ b/hmp.c @@ -771,6 +771,34 @@ void hmp_block_resize(Monitor *mon, const QDict *qdict) hmp_handle_error(mon, &errp); } +void hmp_drive_mirror(Monitor *mon, const QDict *qdict) +{ + const char *device = qdict_get_str(qdict, "device"); + const char *filename = qdict_get_str(qdict, "target"); + const char *format = qdict_get_try_str(qdict, "format"); + int reuse = qdict_get_try_bool(qdict, "reuse", 0); + int full = qdict_get_try_bool(qdict, "full", 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 { + mode = NEW_IMAGE_MODE_ABSOLUTE_PATHS; + } + + qmp_drive_mirror(device, filename, !!format, format, + full ? MIRROR_SYNC_MODE_FULL : MIRROR_SYNC_MODE_TOP, + true, mode, false, 0, &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 7bdd23c23f..34eb2b36f3 100644 --- a/hmp.h +++ b/hmp.h @@ -51,6 +51,7 @@ void hmp_block_passwd(Monitor *mon, const QDict *qdict); void hmp_balloon(Monitor *mon, const QDict *qdict); void hmp_block_resize(Monitor *mon, const QDict *qdict); void hmp_snapshot_blkdev(Monitor *mon, const QDict *qdict); +void hmp_drive_mirror(Monitor *mon, const QDict *qdict); void hmp_migrate_cancel(Monitor *mon, const QDict *qdict); void hmp_migrate_set_downtime(Monitor *mon, const QDict *qdict); void hmp_migrate_set_speed(Monitor *mon, const QDict *qdict); diff --git a/qapi-schema.json b/qapi-schema.json index 8c4b7c808b..a066cd5ca2 100644 --- a/qapi-schema.json +++ b/qapi-schema.json @@ -1606,6 +1606,40 @@ 'data': { 'device': 'str', '*base': 'str', 'top': 'str', '*speed': 'int' } } +## +# @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 to +# probe if @mode is 'existing', else the format of the source +# +# @mode: #optional whether and how QEMU should create a new image, default is +# 'absolute-paths'. +# +# @speed: #optional the maximum speed, in bytes per second +# +# @sync: what parts of the disk image should be copied to the destination +# (all the disk, only the sectors allocated in the topmost image, or +# only new I/O). +# +# Returns: nothing on success +# If @device is not a valid block device, DeviceNotFound +# +# Since 1.3 +## +{ 'command': 'drive-mirror', + 'data': { 'device': 'str', 'target': 'str', '*format': 'str', + 'sync': 'MirrorSyncMode', '*mode': 'NewImageMode', + '*speed': 'int' } } + +## # @migrate_cancel # # Cancel the current executing migration process. diff --git a/qmp-commands.hx b/qmp-commands.hx index 4f9c711585..614baea784 100644 --- a/qmp-commands.hx +++ b/qmp-commands.hx @@ -933,6 +933,48 @@ Example: "format": "qcow2" } } <- { "return": {} } +EQMP + + { + .name = "drive-mirror", + .args_type = "sync:s,device:B,target:s,speed:i?,mode:s?,format:s?", + .mhandler.cmd_new = qmp_marshal_input_drive_mirror, + }, + +SQMP +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 it does not +exist, a new file will be created. format specifies the format of the +mirror image, default is to probe if mode='existing', else the format +of the source. + +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') +- "speed": maximum speed of the streaming job, in bytes per second + (json-int) +- "sync": what parts of the disk image should be copied to the destination; + possibilities include "full" for all the disk, "top" for only the sectors + allocated in the topmost image, or "none" to only replicate new I/O + (MirrorSyncMode). + + +Example: + +-> { "execute": "drive-mirror", "arguments": { "device": "ide-hd0", + "target": "/some/place/my-image", + "sync": "full", + "format": "qcow2" } } +<- { "return": {} } + EQMP {