diff options
| -rw-r--r-- | Makefile.objs | 1 | ||||
| -rw-r--r-- | qapi/block-core.json | 13 | ||||
| -rw-r--r-- | replication.c | 107 | ||||
| -rw-r--r-- | replication.h | 174 |
4 files changed, 295 insertions, 0 deletions
diff --git a/Makefile.objs b/Makefile.objs index 6d5ddcfd3e..7301544cdd 100644 --- a/Makefile.objs +++ b/Makefile.objs @@ -15,6 +15,7 @@ block-obj-$(CONFIG_POSIX) += aio-posix.o block-obj-$(CONFIG_WIN32) += aio-win32.o block-obj-y += block/ block-obj-y += qemu-io-cmds.o +block-obj-$(CONFIG_REPLICATION) += replication.o block-obj-m = block/ diff --git a/qapi/block-core.json b/qapi/block-core.json index 31f9990754..4755c759fd 100644 --- a/qapi/block-core.json +++ b/qapi/block-core.json @@ -2163,6 +2163,19 @@ '*debug-level': 'int' } } ## +# @ReplicationMode +# +# An enumeration of replication modes. +# +# @primary: Primary mode, the vm's state will be sent to secondary QEMU. +# +# @secondary: Secondary mode, receive the vm's state from primary QEMU. +# +# Since: 2.8 +## +{ 'enum' : 'ReplicationMode', 'data' : [ 'primary', 'secondary' ] } + +## # @BlockdevOptions # # Options for creating a block device. Many options are available for all diff --git a/replication.c b/replication.c new file mode 100644 index 0000000000..be3a42f9c9 --- /dev/null +++ b/replication.c @@ -0,0 +1,107 @@ +/* + * Replication filter + * + * Copyright (c) 2016 HUAWEI TECHNOLOGIES CO., LTD. + * Copyright (c) 2016 Intel Corporation + * Copyright (c) 2016 FUJITSU LIMITED + * + * Author: + * Changlong Xie <xiecl.fnst@cn.fujitsu.com> + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + */ + +#include "qemu/osdep.h" +#include "qapi/error.h" +#include "replication.h" + +static QLIST_HEAD(, ReplicationState) replication_states; + +ReplicationState *replication_new(void *opaque, ReplicationOps *ops) +{ + ReplicationState *rs; + + assert(ops != NULL); + rs = g_new0(ReplicationState, 1); + rs->opaque = opaque; + rs->ops = ops; + QLIST_INSERT_HEAD(&replication_states, rs, node); + + return rs; +} + +void replication_remove(ReplicationState *rs) +{ + if (rs) { + QLIST_REMOVE(rs, node); + g_free(rs); + } +} + +/* + * The caller of the function MUST make sure vm stopped + */ +void replication_start_all(ReplicationMode mode, Error **errp) +{ + ReplicationState *rs, *next; + Error *local_err = NULL; + + QLIST_FOREACH_SAFE(rs, &replication_states, node, next) { + if (rs->ops && rs->ops->start) { + rs->ops->start(rs, mode, &local_err); + } + if (local_err) { + error_propagate(errp, local_err); + return; + } + } +} + +void replication_do_checkpoint_all(Error **errp) +{ + ReplicationState *rs, *next; + Error *local_err = NULL; + + QLIST_FOREACH_SAFE(rs, &replication_states, node, next) { + if (rs->ops && rs->ops->checkpoint) { + rs->ops->checkpoint(rs, &local_err); + } + if (local_err) { + error_propagate(errp, local_err); + return; + } + } +} + +void replication_get_error_all(Error **errp) +{ + ReplicationState *rs, *next; + Error *local_err = NULL; + + QLIST_FOREACH_SAFE(rs, &replication_states, node, next) { + if (rs->ops && rs->ops->get_error) { + rs->ops->get_error(rs, &local_err); + } + if (local_err) { + error_propagate(errp, local_err); + return; + } + } +} + +void replication_stop_all(bool failover, Error **errp) +{ + ReplicationState *rs, *next; + Error *local_err = NULL; + + QLIST_FOREACH_SAFE(rs, &replication_states, node, next) { + if (rs->ops && rs->ops->stop) { + rs->ops->stop(rs, failover, &local_err); + } + if (local_err) { + error_propagate(errp, local_err); + return; + } + } +} diff --git a/replication.h b/replication.h new file mode 100644 index 0000000000..ece6ca6133 --- /dev/null +++ b/replication.h @@ -0,0 +1,174 @@ +/* + * Replication filter + * + * Copyright (c) 2016 HUAWEI TECHNOLOGIES CO., LTD. + * Copyright (c) 2016 Intel Corporation + * Copyright (c) 2016 FUJITSU LIMITED + * + * Author: + * Changlong Xie <xiecl.fnst@cn.fujitsu.com> + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + */ + +#ifndef REPLICATION_H +#define REPLICATION_H + +#include "qemu/queue.h" + +typedef struct ReplicationOps ReplicationOps; +typedef struct ReplicationState ReplicationState; + +/** + * SECTION:replication.h + * @title:Base Replication System + * @short_description: interfaces for handling replication + * + * The Replication Model provides a framework for handling Replication + * + * <example> + * <title>How to use replication interfaces</title> + * <programlisting> + * #include "replication.h" + * + * typedef struct BDRVReplicationState { + * ReplicationState *rs; + * } BDRVReplicationState; + * + * static void replication_start(ReplicationState *rs, ReplicationMode mode, + * Error **errp); + * static void replication_do_checkpoint(ReplicationState *rs, Error **errp); + * static void replication_get_error(ReplicationState *rs, Error **errp); + * static void replication_stop(ReplicationState *rs, bool failover, + * Error **errp); + * + * static ReplicationOps replication_ops = { + * .start = replication_start, + * .checkpoint = replication_do_checkpoint, + * .get_error = replication_get_error, + * .stop = replication_stop, + * } + * + * static int replication_open(BlockDriverState *bs, QDict *options, + * int flags, Error **errp) + * { + * BDRVReplicationState *s = bs->opaque; + * s->rs = replication_new(bs, &replication_ops); + * return 0; + * } + * + * static void replication_close(BlockDriverState *bs) + * { + * BDRVReplicationState *s = bs->opaque; + * replication_remove(s->rs); + * } + * + * BlockDriver bdrv_replication = { + * .format_name = "replication", + * .protocol_name = "replication", + * .instance_size = sizeof(BDRVReplicationState), + * + * .bdrv_open = replication_open, + * .bdrv_close = replication_close, + * }; + * + * static void bdrv_replication_init(void) + * { + * bdrv_register(&bdrv_replication); + * } + * + * block_init(bdrv_replication_init); + * </programlisting> + * </example> + * + * We create an example about how to use replication interfaces in above. + * Then in migration, we can use replication_(start/stop/do_checkpoint/ + * get_error)_all to handle all replication operations. + */ + +/** + * ReplicationState: + * @opaque: opaque pointer value passed to this ReplicationState + * @ops: replication operation of this ReplicationState + * @node: node that we will insert into @replication_states QLIST + */ +struct ReplicationState { + void *opaque; + ReplicationOps *ops; + QLIST_ENTRY(ReplicationState) node; +}; + +/** + * ReplicationOps: + * @start: callback to start replication + * @stop: callback to stop replication + * @checkpoint: callback to do checkpoint + * @get_error: callback to check if error occurred during replication + */ +struct ReplicationOps { + void (*start)(ReplicationState *rs, ReplicationMode mode, Error **errp); + void (*stop)(ReplicationState *rs, bool failover, Error **errp); + void (*checkpoint)(ReplicationState *rs, Error **errp); + void (*get_error)(ReplicationState *rs, Error **errp); +}; + +/** + * replication_new: + * @opaque: opaque pointer value passed to ReplicationState + * @ops: replication operation of the new relevant ReplicationState + * + * Called to create a new ReplicationState instance, and then insert it + * into @replication_states QLIST + * + * Returns: the new ReplicationState instance + */ +ReplicationState *replication_new(void *opaque, ReplicationOps *ops); + +/** + * replication_remove: + * @rs: the ReplicationState instance to remove + * + * Called to remove a ReplicationState instance, and then delete it from + * @replication_states QLIST + */ +void replication_remove(ReplicationState *rs); + +/** + * replication_start_all: + * @mode: replication mode that could be "primary" or "secondary" + * @errp: returns an error if this function fails + * + * Start replication, called in migration/checkpoint thread + * + * Note: the caller of the function MUST make sure vm stopped + */ +void replication_start_all(ReplicationMode mode, Error **errp); + +/** + * replication_do_checkpoint_all: + * @errp: returns an error if this function fails + * + * This interface is called after all VM state is transferred to Secondary QEMU + */ +void replication_do_checkpoint_all(Error **errp); + +/** + * replication_get_error_all: + * @errp: returns an error if this function fails + * + * This interface is called to check if error occurred during replication + */ +void replication_get_error_all(Error **errp); + +/** + * replication_stop_all: + * @failover: boolean value that indicates if we need do failover or not + * @errp: returns an error if this function fails + * + * It is called on failover. The vm should be stopped before calling it, if you + * use this API to shutdown the guest, or other things except failover + */ +void replication_stop_all(bool failover, Error **errp); + +#endif /* REPLICATION_H */ |