diff --git a/block.c b/block.c index 106238d0b7..9ecadf002f 100644 --- a/block.c +++ b/block.c @@ -5766,3 +5766,28 @@ bool bdrv_is_first_non_filter(BlockDriverState *candidate) return false; } + +BlockDriverState *check_to_replace_node(const char *node_name, Error **errp) +{ + BlockDriverState *to_replace_bs = bdrv_find_node(node_name); + if (!to_replace_bs) { + error_setg(errp, "Node name '%s' not found", node_name); + return NULL; + } + + if (bdrv_op_is_blocked(to_replace_bs, BLOCK_OP_TYPE_REPLACE, errp)) { + return NULL; + } + + /* We don't want arbitrary node of the BDS chain to be replaced only the top + * most non filter in order to prevent data corruption. + * Another benefit is that this tests exclude backing files which are + * blocked by the backing blockers. + */ + if (!bdrv_is_first_non_filter(to_replace_bs)) { + error_setg(errp, "Only top most non filter can be replaced"); + return NULL; + } + + return to_replace_bs; +} diff --git a/block/mirror.c b/block/mirror.c index 7c9f898089..6c3ee7041c 100644 --- a/block/mirror.c +++ b/block/mirror.c @@ -32,6 +32,12 @@ typedef struct MirrorBlockJob { RateLimit limit; BlockDriverState *target; BlockDriverState *base; + /* The name of the graph node to replace */ + char *replaces; + /* The BDS to replace */ + BlockDriverState *to_replace; + /* Used to block operations on the drive-mirror-replace target */ + Error *replace_blocker; bool is_none_mode; BlockdevOnError on_source_error, on_target_error; bool synced; @@ -500,10 +506,14 @@ immediate_exit: bdrv_release_dirty_bitmap(bs, s->dirty_bitmap); bdrv_iostatus_disable(s->target); if (s->should_complete && ret == 0) { - if (bdrv_get_flags(s->target) != bdrv_get_flags(s->common.bs)) { - bdrv_reopen(s->target, bdrv_get_flags(s->common.bs), NULL); + BlockDriverState *to_replace = s->common.bs; + if (s->to_replace) { + to_replace = s->to_replace; } - bdrv_swap(s->target, s->common.bs); + if (bdrv_get_flags(s->target) != bdrv_get_flags(to_replace)) { + bdrv_reopen(s->target, bdrv_get_flags(to_replace), NULL); + } + bdrv_swap(s->target, to_replace); if (s->common.driver->job_type == BLOCK_JOB_TYPE_COMMIT) { /* drop the bs loop chain formed by the swap: break the loop then * trigger the unref from the top one */ @@ -512,6 +522,12 @@ immediate_exit: bdrv_unref(p); } } + if (s->to_replace) { + bdrv_op_unblock_all(s->to_replace, s->replace_blocker); + error_free(s->replace_blocker); + bdrv_unref(s->to_replace); + } + g_free(s->replaces); bdrv_unref(s->target); block_job_completed(&s->common, ret); } @@ -550,6 +566,20 @@ static void mirror_complete(BlockJob *job, Error **errp) return; } + /* check the target bs is not blocked and block all operations on it */ + if (s->replaces) { + s->to_replace = check_to_replace_node(s->replaces, &local_err); + if (!s->to_replace) { + error_propagate(errp, local_err); + return; + } + + error_setg(&s->replace_blocker, + "block device is in use by block-job-complete"); + bdrv_op_block_all(s->to_replace, s->replace_blocker); + bdrv_ref(s->to_replace); + } + s->should_complete = true; block_job_resume(job); } @@ -572,14 +602,15 @@ static const BlockJobDriver commit_active_job_driver = { }; static void mirror_start_job(BlockDriverState *bs, BlockDriverState *target, - int64_t speed, int64_t granularity, - int64_t buf_size, - BlockdevOnError on_source_error, - BlockdevOnError on_target_error, - BlockDriverCompletionFunc *cb, - void *opaque, Error **errp, - const BlockJobDriver *driver, - bool is_none_mode, BlockDriverState *base) + const char *replaces, + int64_t speed, int64_t granularity, + int64_t buf_size, + BlockdevOnError on_source_error, + BlockdevOnError on_target_error, + BlockDriverCompletionFunc *cb, + void *opaque, Error **errp, + const BlockJobDriver *driver, + bool is_none_mode, BlockDriverState *base) { MirrorBlockJob *s; @@ -610,6 +641,7 @@ static void mirror_start_job(BlockDriverState *bs, BlockDriverState *target, return; } + s->replaces = g_strdup(replaces); s->on_source_error = on_source_error; s->on_target_error = on_target_error; s->target = target; @@ -631,6 +663,7 @@ static void mirror_start_job(BlockDriverState *bs, BlockDriverState *target, } void mirror_start(BlockDriverState *bs, BlockDriverState *target, + const char *replaces, int64_t speed, int64_t granularity, int64_t buf_size, MirrorSyncMode mode, BlockdevOnError on_source_error, BlockdevOnError on_target_error, @@ -642,7 +675,8 @@ void mirror_start(BlockDriverState *bs, BlockDriverState *target, is_none_mode = mode == MIRROR_SYNC_MODE_NONE; base = mode == MIRROR_SYNC_MODE_TOP ? bs->backing_hd : NULL; - mirror_start_job(bs, target, speed, granularity, buf_size, + mirror_start_job(bs, target, replaces, + speed, granularity, buf_size, on_source_error, on_target_error, cb, opaque, errp, &mirror_job_driver, is_none_mode, base); } @@ -690,7 +724,7 @@ void commit_active_start(BlockDriverState *bs, BlockDriverState *base, } bdrv_ref(base); - mirror_start_job(bs, base, speed, 0, 0, + mirror_start_job(bs, base, NULL, speed, 0, 0, on_error, on_error, cb, opaque, &local_err, &commit_active_job_driver, false, base); if (local_err) { diff --git a/blockdev.c b/blockdev.c index 943301226d..69b7c2a8c5 100644 --- a/blockdev.c +++ b/blockdev.c @@ -2100,6 +2100,7 @@ BlockDeviceInfoList *qmp_query_named_block_nodes(Error **errp) void qmp_drive_mirror(const char *device, const char *target, bool has_format, const char *format, bool has_node_name, const char *node_name, + bool has_replaces, const char *replaces, enum MirrorSyncMode sync, bool has_mode, enum NewImageMode mode, bool has_speed, int64_t speed, @@ -2187,6 +2188,29 @@ void qmp_drive_mirror(const char *device, const char *target, return; } + if (has_replaces) { + BlockDriverState *to_replace_bs; + + if (!has_node_name) { + error_setg(errp, "a node-name must be provided when replacing a" + " named node of the graph"); + return; + } + + to_replace_bs = check_to_replace_node(replaces, &local_err); + + if (!to_replace_bs) { + error_propagate(errp, local_err); + return; + } + + if (size != bdrv_getlength(to_replace_bs)) { + error_setg(errp, "cannot replace image with a mirror image of " + "different size"); + return; + } + } + if ((sync == MIRROR_SYNC_MODE_FULL || !source) && mode != NEW_IMAGE_MODE_EXISTING) { @@ -2231,7 +2255,12 @@ void qmp_drive_mirror(const char *device, const char *target, return; } - mirror_start(bs, target_bs, speed, granularity, buf_size, sync, + /* pass the node name to replace to mirror start since it's loose coupling + * and will allow to check whether the node still exist at mirror completion + */ + mirror_start(bs, target_bs, + has_replaces ? replaces : NULL, + speed, granularity, buf_size, sync, on_source_error, on_target_error, block_job_cb, bs, &local_err); if (local_err != NULL) { diff --git a/hmp.c b/hmp.c index 73acc3283c..6429e6b447 100644 --- a/hmp.c +++ b/hmp.c @@ -933,7 +933,7 @@ void hmp_drive_mirror(Monitor *mon, const QDict *qdict) } qmp_drive_mirror(device, filename, !!format, format, - false, NULL, + false, NULL, false, NULL, full ? MIRROR_SYNC_MODE_FULL : MIRROR_SYNC_MODE_TOP, true, mode, false, 0, false, 0, false, 0, false, 0, false, 0, &err); diff --git a/include/block/block.h b/include/block/block.h index d0baf4fb83..b53833d1d6 100644 --- a/include/block/block.h +++ b/include/block/block.h @@ -175,6 +175,7 @@ typedef enum BlockOpType { BLOCK_OP_TYPE_MIRROR, BLOCK_OP_TYPE_RESIZE, BLOCK_OP_TYPE_STREAM, + BLOCK_OP_TYPE_REPLACE, BLOCK_OP_TYPE_MAX, } BlockOpType; @@ -314,6 +315,9 @@ bool bdrv_recurse_is_first_non_filter(BlockDriverState *bs, BlockDriverState *candidate); bool bdrv_is_first_non_filter(BlockDriverState *candidate); +/* check if a named node can be replaced when doing drive-mirror */ +BlockDriverState *check_to_replace_node(const char *node_name, Error **errp); + /* async block I/O */ typedef void BlockDriverDirtyHandler(BlockDriverState *bs, int64_t sector, int sector_num); diff --git a/include/block/block_int.h b/include/block/block_int.h index 135c5dc0e9..53e77cf11e 100644 --- a/include/block/block_int.h +++ b/include/block/block_int.h @@ -489,6 +489,8 @@ void commit_active_start(BlockDriverState *bs, BlockDriverState *base, * mirror_start: * @bs: Block device to operate on. * @target: Block device to write to. + * @replaces: Block graph node name to replace once the mirror is done. Can + * only be used when full mirroring is selected. * @speed: The maximum speed, in bytes per second, or 0 for unlimited. * @granularity: The chosen granularity for the dirty bitmap. * @buf_size: The amount of data that can be in flight at one time. @@ -505,6 +507,7 @@ void commit_active_start(BlockDriverState *bs, BlockDriverState *base, * @bs will be switched to read from @target. */ void mirror_start(BlockDriverState *bs, BlockDriverState *target, + const char *replaces, int64_t speed, int64_t granularity, int64_t buf_size, MirrorSyncMode mode, BlockdevOnError on_source_error, BlockdevOnError on_target_error, diff --git a/qapi/block-core.json b/qapi/block-core.json index ff7224f647..406ce03951 100644 --- a/qapi/block-core.json +++ b/qapi/block-core.json @@ -768,6 +768,10 @@ # @node-name: #optional the new block driver state node name in the graph # (Since 2.1) # +# @replaces: #optional with sync=full graph node name to be replaced by the new +# image when a whole image copy is done. This can be used to repair +# broken Quorum files. (Since 2.1) +# # @mode: #optional whether and how QEMU should create a new image, default is # 'absolute-paths'. # @@ -800,7 +804,7 @@ ## { 'command': 'drive-mirror', 'data': { 'device': 'str', 'target': 'str', '*format': 'str', - '*node-name': 'str', + '*node-name': 'str', '*replaces': 'str', 'sync': 'MirrorSyncMode', '*mode': 'NewImageMode', '*speed': 'int', '*granularity': 'uint32', '*buf-size': 'int', '*on-source-error': 'BlockdevOnError', diff --git a/qmp-commands.hx b/qmp-commands.hx index 5254938878..d342b8a067 100644 --- a/qmp-commands.hx +++ b/qmp-commands.hx @@ -1293,7 +1293,7 @@ EQMP { .name = "drive-mirror", .args_type = "sync:s,device:B,target:s,speed:i?,mode:s?,format:s?," - "node-name:s?," + "node-name:s?,replaces:s?," "on-source-error:s?,on-target-error:s?," "granularity:i?,buf-size:i?", .mhandler.cmd_new = qmp_marshal_input_drive_mirror, @@ -1317,6 +1317,8 @@ Arguments: - "format": format of new image (json-string, optional) - "node-name": the name of the new block driver state in the node graph (json-string, optional) +- "replaces": the block driver node name to replace when finished + (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