The Wednesday 29 Jan 2014 à 13:07:37 (+0800), Fam Zheng wrote :
> Similar to drive-backup, but this command uses a device id as target
> instead of creating/opening an image file.
>
> Also add blocker on target bs, since the target is also a named device
> now.
>
> Add check and report error for bs == target which became possible but is
> an illegal case with introduction of blockdev-backup.
>
> Signed-off-by: Fam Zheng <f...@redhat.com>
> ---
> block/backup.c | 26 ++++++++++++++++++++++++++
> blockdev.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++
> qapi-schema.json | 49 +++++++++++++++++++++++++++++++++++++++++++++++++
> qmp-commands.hx | 44 ++++++++++++++++++++++++++++++++++++++++++++
> 4 files changed, 166 insertions(+)
>
> diff --git a/block/backup.c b/block/backup.c
> index 15a2e55..ea46340 100644
> --- a/block/backup.c
> +++ b/block/backup.c
> @@ -344,6 +344,7 @@ static void coroutine_fn backup_run(void *opaque)
> hbitmap_free(job->bitmap);
>
> bdrv_iostatus_disable(target);
> + bdrv_op_unblock_all(target, job->common.blocker);
> bdrv_unref(target);
>
> block_job_completed(&job->common, ret);
> @@ -362,6 +363,11 @@ void backup_start(BlockDriverState *bs, BlockDriverState
> *target,
> assert(target);
> assert(cb);
>
> + if (bs == target) {
> + error_setg(errp, "Source and target cannot be the same");
> + return;
> + }
> +
> if ((on_source_error == BLOCKDEV_ON_ERROR_STOP ||
> on_source_error == BLOCKDEV_ON_ERROR_ENOSPC) &&
> !bdrv_iostatus_is_enabled(bs)) {
> @@ -369,6 +375,24 @@ void backup_start(BlockDriverState *bs, BlockDriverState
> *target,
> return;
> }
>
> + if (!bdrv_is_inserted(bs)) {
> + error_set(errp, QERR_DEVICE_HAS_NO_MEDIUM, bs->device_name);
> + return;
> + }
> +
> + if (!bdrv_is_inserted(target)) {
> + error_set(errp, QERR_DEVICE_HAS_NO_MEDIUM, target->device_name);
> + return;
> + }
> +
> + if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_BACKUP_SOURCE, errp)) {
> + return;
> + }
> +
> + if (bdrv_op_is_blocked(target, BLOCK_OP_TYPE_BACKUP_TARGET, errp)) {
> + return;
> + }
> +
> len = bdrv_getlength(bs);
> if (len < 0) {
> error_setg_errno(errp, -len, "unable to get length for '%s'",
> @@ -382,6 +406,8 @@ void backup_start(BlockDriverState *bs, BlockDriverState
> *target,
> return;
> }
>
> + bdrv_op_block_all(target, job->common.blocker);
> +
> job->on_source_error = on_source_error;
> job->on_target_error = on_target_error;
> job->target = target;
> diff --git a/blockdev.c b/blockdev.c
> index ffaa6a9..b346cc1 100644
> --- a/blockdev.c
> +++ b/blockdev.c
> @@ -1940,6 +1940,8 @@ void qmp_drive_backup(const char *device, const char
> *target,
> return;
> }
>
> + /* Although backup_run has this check too, we need to use bs->drv below,
> so
> + * do an early check redundantly. */
> if (!bdrv_is_inserted(bs)) {
> error_set(errp, QERR_DEVICE_HAS_NO_MEDIUM, device);
> return;
> @@ -1956,6 +1958,7 @@ void qmp_drive_backup(const char *device, const char
> *target,
> }
> }
>
> + /* Early check to avoid creating target */
> if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_BACKUP_SOURCE, errp)) {
> return;
> }
> @@ -2019,6 +2022,50 @@ BlockDeviceInfoList *qmp_query_named_block_nodes(Error
> **errp)
> return bdrv_named_nodes_list();
> }
>
> +void qmp_blockdev_backup(const char *device, const char *target,
> + enum MirrorSyncMode sync,
> + bool has_speed, int64_t speed,
> + bool has_on_source_error,
> + BlockdevOnError on_source_error,
> + bool has_on_target_error,
> + BlockdevOnError on_target_error,
> + Error **errp)
> +{
> + BlockDriverState *bs;
> + BlockDriverState *target_bs;
> + Error *local_err = NULL;
> +
> + if (!has_speed) {
> + speed = 0;
> + }
> + if (!has_on_source_error) {
> + on_source_error = BLOCKDEV_ON_ERROR_REPORT;
> + }
> + if (!has_on_target_error) {
> + on_target_error = BLOCKDEV_ON_ERROR_REPORT;
> + }
> +
> + bs = bdrv_find(device);
This and the qmp prototype should be upgraded to the new device and node-name
alternative and make use of bdrv_lookup_bs().
> + if (!bs) {
> + error_set(errp, QERR_DEVICE_NOT_FOUND, device);
> + return;
> + }
> +
> + target_bs = bdrv_find(target);
> + if (!target_bs) {
> + error_set(errp, QERR_DEVICE_NOT_FOUND, target);
> + return;
> + }
> +
> + bdrv_ref(target_bs);
> + backup_start(bs, target_bs, speed, sync, on_source_error,
> on_target_error,
> + block_job_cb, bs, &local_err);
> + if (local_err != NULL) {
> + bdrv_unref(target_bs);
> + error_propagate(errp, local_err);
> + }
> +}
> +
> #define DEFAULT_MIRROR_BUF_SIZE (10 << 20)
>
> void qmp_drive_mirror(const char *device, const char *target,
> diff --git a/qapi-schema.json b/qapi-schema.json
> index 05ced9d..a92e1be 100644
> --- a/qapi-schema.json
> +++ b/qapi-schema.json
> @@ -1840,6 +1840,40 @@
> '*on-target-error': 'BlockdevOnError' } }
>
> ##
> +# @BlockdevBackup
> +#
> +# @device: the name of the device which should be copied.
> +#
> +# @target: the name of the backup target device.
> +#
> +# @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).
> +#
> +# @speed: #optional the maximum speed, in bytes per second.
> +#
> +# @on-source-error: #optional the action to take on an error on the source,
> +# default 'report'. 'stop' and 'enospc' can only be used
> +# if the block device supports io-status (see BlockInfo).
> +#
> +# @on-target-error: #optional the action to take on an error on the target,
> +# default 'report' (no limitations, since this applies to
> +# a different block device than @device).
> +#
> +# Note that @on-source-error and @on-target-error only affect background I/O.
> +# If an error occurs during a guest write request, the device's rerror/werror
> +# actions will be used.
> +#
> +# Since: 2.0
> +##
> +{ 'type': 'BlockdevBackup',
> + 'data': { 'device': 'str', 'target': 'str',
'*device': 'str', '*node-name': str,
I don't know if it's necessary for target.
> + 'sync': 'MirrorSyncMode',
> + '*speed': 'int',
> + '*on-source-error': 'BlockdevOnError',
> + '*on-target-error': 'BlockdevOnError' } }
> +
> +##
> # @Abort
> #
> # This action can be used to test transaction failure.
> @@ -2048,6 +2082,21 @@
> { 'command': 'query-named-block-nodes', 'returns': [ 'BlockDeviceInfo' ] }
>
> ##
> +# @blockdev-backup
> +#
> +# Block device version for drive-backup command. Use existing device as
> target
> +# of backup.
> +#
> +# For the arguments, see the documentation of BlockdevBackup.
> +#
> +# Returns: Nothing on success.
> +# If @device or @target is not a valid block device, DeviceNotFound.
> +#
> +# Since 2.0
> +##
> +{ 'command': 'blockdev-backup', 'data': 'BlockdevBackup' }
> +
> +##
> # @drive-mirror
> #
> # Start mirroring a block device's writes to a new destination.
> diff --git a/qmp-commands.hx b/qmp-commands.hx
> index cce6b81..c3ee46a 100644
> --- a/qmp-commands.hx
> +++ b/qmp-commands.hx
> @@ -1054,6 +1054,50 @@ Example:
> "sync": "full",
> "target": "backup.img" } }
> <- { "return": {} }
> +
> +EQMP
> +
> + {
> + .name = "blockdev-backup",
> + .args_type = "sync:s,device:B,target:B,speed:i?,"
> + "on-source-error:s?,on-target-error:s?",
> + .mhandler.cmd_new = qmp_marshal_input_blockdev_backup,
> + },
> +
> +SQMP
> +blockdev-backup
> +------------
> +
> +The device version of drive-backup: this command takes a existing named
> device
> +as backup target.
> +
> +Arguments:
> +
> +- "device": the name of the device which should be copied.
> + (json-string)
> +- "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.
> + (json-string)
> +- "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).
> +- "speed": the maximum speed, in bytes per second (json-int, optional)
> +- "on-source-error": the action to take on an error on the source, default
> + 'report'. 'stop' and 'enospc' can only be used
> + if the block device supports io-status.
> + (BlockdevOnError, optional)
> +- "on-target-error": the action to take on an error on the target, default
> + 'report' (no limitations, since this applies to
> + a different block device than device).
> + (BlockdevOnError, optional)
> +
> +Example:
> +-> { "execute": "blockdev-backup", "arguments": { "device": "src-id",
> + "target": "tgt-id" } }
> +<- { "return": {} }
> +
> EQMP
>
> {
> --
> 1.8.5.3
>
>
