On 2015-03-04 at 23:15, John Snow wrote:
This adds two qmp commands to transactions.
block-dirty-bitmap-add allows you to create a bitmap simultaneously
alongside a new full backup to accomplish a clean synchronization
point.
block-dirty-bitmap-clear allows you to reset a bitmap back to as-if
it were new, which can also be used alongside a full backup to
accomplish a clean synchronization point.
Signed-off-by: Fam Zheng <f...@redhat.com>
Signed-off-by: John Snow <js...@redhat.com>
---
blockdev.c | 101 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
qapi-schema.json | 6 +++-
2 files changed, 106 insertions(+), 1 deletion(-)
diff --git a/blockdev.c b/blockdev.c
index e0671be..5120af1 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -1664,6 +1664,96 @@ static void blockdev_backup_clean(BlkTransactionState
*common)
}
}
+typedef struct BlockDirtyBitmapState {
+ BlkTransactionState common;
+ BdrvDirtyBitmap *bitmap;
+ BlockDriverState *bs;
+ AioContext *aio_context;
+ bool prepared;
+} BlockDirtyBitmapState;
+
+static void block_dirty_bitmap_add_prepare(BlkTransactionState *common,
+ Error **errp)
+{
+ Error *local_err = NULL;
+ BlockDirtyBitmapAdd *action;
+ BlockDirtyBitmapState *state = DO_UPCAST(BlockDirtyBitmapState,
+ common, common);
+
+ action = common->action->block_dirty_bitmap_add;
+ /* AIO context taken within qmp_block_dirty_bitmap_add */
+ qmp_block_dirty_bitmap_add(action->node, action->name,
+ action->has_granularity, action->granularity,
+ &local_err);
+
+ if (!local_err) {
+ state->prepared = true;
+ } else {
+ error_propagate(errp, local_err);
+ }
+}
+
+static void block_dirty_bitmap_add_abort(BlkTransactionState *common)
+{
+ BlockDirtyBitmapAdd *action;
+ BlockDirtyBitmapState *state = DO_UPCAST(BlockDirtyBitmapState,
Indentation is still off.
+ common, common);
+
+ action = common->action->block_dirty_bitmap_add;
+ /* Should not be able to fail: IF the bitmap was added via .prepare(),
+ * then the node reference and bitmap name must have been valid.
+ */
+ if (state->prepared) {
+ qmp_block_dirty_bitmap_remove(action->node, action->name,
&error_abort);
+ }
+}
+
+static void block_dirty_bitmap_clear_prepare(BlkTransactionState *common,
+ Error **errp)
+{
+ BlockDirtyBitmapState *state = DO_UPCAST(BlockDirtyBitmapState,
+ common, common);
+ BlockDirtyBitmap *action;
+
+ action = common->action->block_dirty_bitmap_clear;
+ state->bitmap = block_dirty_bitmap_lookup(action->node,
+ action->name,
+ &state->bs,
+ errp);
This will need fix-up for v3 (and following, probably) of your
transactionless series (&state->aio_context as the fourth parameter).
+ if (!state->bitmap) {
+ return;
+ }
+
+ if (bdrv_dirty_bitmap_frozen(state->bitmap)) {
+ error_setg(errp, "Cannot modify a frozen bitmap");
+ return;
+ } else if (!bdrv_dirty_bitmap_enabled(state->bitmap)) {
+ error_setg(errp, "Cannot clear a disabled bitmap");
+ return;
+ }
+
+ /* AioContext is released in .clean() */
+ state->aio_context = bdrv_get_aio_context(state->bs);
+ aio_context_acquire(state->aio_context);
And this will probably need to be dropped for v4 of said series.
Other than that, looks good.
Max
+}
+
+static void block_dirty_bitmap_clear_commit(BlkTransactionState *common)
+{
+ BlockDirtyBitmapState *state = DO_UPCAST(BlockDirtyBitmapState,
+ common, common);
+ bdrv_clear_dirty_bitmap(state->bitmap);
+}
+
+static void block_dirty_bitmap_clear_clean(BlkTransactionState *common)
+{
+ BlockDirtyBitmapState *state = DO_UPCAST(BlockDirtyBitmapState,
+ common, common);
+
+ if (state->aio_context) {
+ aio_context_release(state->aio_context);
+ }
+}
+
static void abort_prepare(BlkTransactionState *common, Error **errp)
{
error_setg(errp, "Transaction aborted using Abort action");
@@ -1704,6 +1794,17 @@ static const BdrvActionOps actions[] = {
.abort = internal_snapshot_abort,
.clean = internal_snapshot_clean,
},
+ [TRANSACTION_ACTION_KIND_BLOCK_DIRTY_BITMAP_ADD] = {
+ .instance_size = sizeof(BlockDirtyBitmapState),
+ .prepare = block_dirty_bitmap_add_prepare,
+ .abort = block_dirty_bitmap_add_abort,
+ },
+ [TRANSACTION_ACTION_KIND_BLOCK_DIRTY_BITMAP_CLEAR] = {
+ .instance_size = sizeof(BlockDirtyBitmapState),
+ .prepare = block_dirty_bitmap_clear_prepare,
+ .commit = block_dirty_bitmap_clear_commit,
+ .clean = block_dirty_bitmap_clear_clean,
+ }
};
/*
diff --git a/qapi-schema.json b/qapi-schema.json
index e16f8eb..12c61f3 100644
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -1332,6 +1332,8 @@
# abort since 1.6
# blockdev-snapshot-internal-sync since 1.7
# blockdev-backup since 2.3
+# block-dirty-bitmap-add since 2.3
+# block-dirty-bitmap-clear since 2.3
##
{ 'union': 'TransactionAction',
'data': {
@@ -1339,7 +1341,9 @@
'drive-backup': 'DriveBackup',
'blockdev-backup': 'BlockdevBackup',
'abort': 'Abort',
- 'blockdev-snapshot-internal-sync': 'BlockdevSnapshotInternal'
+ 'blockdev-snapshot-internal-sync': 'BlockdevSnapshotInternal',
+ 'block-dirty-bitmap-add': 'BlockDirtyBitmapAdd',
+ 'block-dirty-bitmap-clear': 'BlockDirtyBitmap'
} }
##
