@@ -138,6 +138,9 @@ static bool blk_root_can_set_aio_ctx(BdrvChild *child, AioContext *ctx,
GSList **ignore, Error **errp);
static void blk_root_set_aio_ctx(BdrvChild *child, AioContext *ctx,
GSList **ignore);
+static bool blk_root_change_aio_ctx(BdrvChild *child, AioContext *ctx,
+ GHashTable *visited, Transaction *tran,
+ Error **errp);
static char *blk_root_get_parent_desc(BdrvChild *child)
{
@@ -336,6 +339,7 @@ static const BdrvChildClass child_root = {
.can_set_aio_ctx = blk_root_can_set_aio_ctx,
.set_aio_ctx = blk_root_set_aio_ctx,
+ .change_aio_ctx = blk_root_change_aio_ctx,
.get_parent_aio_context = blk_root_get_parent_aio_context,
};
@@ -2208,6 +2212,54 @@ int blk_set_aio_context(BlockBackend *blk, AioContext *new_context,
return blk_do_set_aio_context(blk, new_context, true, errp);
}
+typedef struct BdrvStateBlkRootContext {
+ AioContext *new_ctx;
+ BlockBackend *blk;
+} BdrvStateBlkRootContext;
+
+static void blk_root_set_aio_ctx_commit(void *opaque)
+{
+ BdrvStateBlkRootContext *s = opaque;
+ BlockBackend *blk = s->blk;
+
+ blk_do_set_aio_context(blk, s->new_ctx, false, &error_abort);
+}
+
+static TransactionActionDrv set_blk_root_context = {
+ .commit = blk_root_set_aio_ctx_commit,
+ .clean = g_free,
+};
+
+static bool blk_root_change_aio_ctx(BdrvChild *child, AioContext *ctx,
+ GHashTable *visited, Transaction *tran,
+ Error **errp)
+{
+ BlockBackend *blk = child->opaque;
+ BdrvStateBlkRootContext *s;
+
+ if (!blk->allow_aio_context_change) {
+ /*
+ * Manually created BlockBackends (those with a name) that are not
+ * attached to anything can change their AioContext without updating
+ * their user; return an error for others.
+ */
+ if (!blk->name || blk->dev) {
+ /* TODO Add BB name/QOM path */
+ error_setg(errp, "Cannot change iothread of active block backend");
+ return false;
+ }
+ }
+
+ s = g_new(BdrvStateBlkRootContext, 1);
+ *s = (BdrvStateBlkRootContext) {
+ .new_ctx = ctx,
+ .blk = blk,
+ };
+
+ tran_add(tran, &set_blk_root_context, s);
+ return true;
+}
+
static bool blk_root_can_set_aio_ctx(BdrvChild *child, AioContext *ctx,
GSList **ignore, Error **errp)
{
blk_root_change_aio_ctx() is very similar to blk_root_can_set_aio_ctx(), but implements a new transaction so that if all check pass, the new transaction's .commit will take care of changing the BlockBackend AioContext. blk_root_set_aio_ctx_commit() is the same as blk_root_set_aio_ctx(). Note: bdrv_child_try_change_aio_context() is not called by anyone at this point. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> --- block/block-backend.c | 52 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 52 insertions(+)