Re: [PATCH v2 11/19] qemu: block: Implement helpers for dealing with bitmaps during block commit

qemuBlockBitmapsHandleCommitStart prepares for disabling the bitmaps in the 'base' of the commit job so that the bitmaps are not dirtied by the commit job. This needs to be done prior to start of the commit job. qemuBlockBitmapsHandleCommitFinish then calculates the necessary merges that agregate all the bitmaps between the commited images and write them into the base bitmap. Signed-off-by: Peter Krempa <pkrempa(a)redhat.com&gt; --- src/qemu/qemu_block.c | 219 ++++++++++++++++++++++++++++++++++++++++++ src/qemu/qemu_block.h | 14 +++ 2 files changed, 233 insertions(+) diff --git a/src/qemu/qemu_block.c b/src/qemu/qemu_block.c index edebbcd0ce..6853c021ca 100644 --- a/src/qemu/qemu_block.c +++ b/src/qemu/qemu_block.c @@ -2962,6 +2962,225 @@ qemuBlockBitmapsHandleBlockcopy(virStorageSourcePtr src, } +/** + * @topsrc: virStorageSource representing 'top' of the job + * @basesrc: virStorageSource representing 'base' of the job + * @blockNamedNodeData: hash table containing data about bitmaps + * @actions: filled with arguments for a 'transaction' command + * @disabledBitmapsBase: filled with a list of bitmap names which must be disabled + * + * Prepares data for correctly hanlding bitmaps during the start of a commit

+ * job. The bitmaps in the 'base' image must be disabled, so that the writes + * done by the blockjob don't dirty the enabled bitmaps. + * + * @actions and @disabledBitmapsBase are untouched if no bitmaps need + * to be disabled. + */ +int +qemuBlockBitmapsHandleCommitStart(virStorageSourcePtr topsrc, + virStorageSourcePtr basesrc, + virHashTablePtr blockNamedNodeData, + virJSONValuePtr *actions, + char ***disabledBitmapsBase) +{

+static int +qemuBlockBitmapsHandleCommitFinishIterate(void *payload, + const void *entryname, + void *opaque) +{ + struct qemuBlockBitmapsHandleCommitData *data = payload; + const char *bitmapname = entryname; + virJSONValuePtr actions = opaque; + + if (data->skip) + return 0; + + if (data->create) { + if (qemuMonitorTransactionBitmapAdd(actions, data->basenode, bitmapname, + data->persistent, !data-> enable,

+/** + * @topsrc: virStorageSource representing 'top' of the job + * @basesrc: virStorageSource representing 'base' of the job + * @blockNamedNodeData: hash table containing data about bitmaps + * @actions: filled with arguments for a 'transaction' command + * @disabledBitmapsBase: bitmap names which were disabled + * + * Calculates the necessary bitmap merges/additions/enablements to properly + * handle commit of images from 'top' into 'base'. The necessary operations + * in form of argumets of the 'transaction' command are filled into 'actions'

+ * if there is anything to do. Otherwise NULL is returned. + */ +int +qemuBlockBitmapsHandleCommitFinish(virStorageSourcePtr topsrc, + virStorageSourcePtr basesrc, + virHashTablePtr blockNamedNodeData, + virJSONValuePtr *actions, + char **disabledBitmapsBase) +{

+++ b/src/qemu/qemu_block.h @@ -229,6 +229,20 @@ qemuBlockBitmapsHandleBlockcopy(virStorageSourcePtr src, bool shallow, virJSONValuePtr *actions); +int +qemuBlockBitmapsHandleCommitStart(virStorageSourcePtr topsrc, + virStorageSourcePtr basesrc, + virHashTablePtr blockNamedNodeData, + virJSONValuePtr *actions, + char ***disabledBitmapsBase); + +int +qemuBlockBitmapsHandleCommitFinish(virStorageSourcePtr topsrc, + virStorageSourcePtr basesrc, + virHashTablePtr blockNamedNodeData, + virJSONValuePtr *actions, + char **disabledBitmapsBase); + int qemuBlockReopenReadWrite(virDomainObjPtr vm, virStorageSourcePtr src,