configuration: backport async backing parameters from the feature branch (#6961)

* Backport async backing params primitive

* migration follow-up

* link pr

* parameters -> params

* rustfmt::skip block ident

polkadot/runtime/parachains/src/configuration.rs

@@ -23,7 +23,10 @@ use frame_support::{pallet_prelude::*, weights::constants::WEIGHT_REF_TIME_PER_M
 use frame_system::pallet_prelude::*;
 use parity_scale_codec::{Decode, Encode};
 use polkadot_parachain::primitives::{MAX_HORIZONTAL_MESSAGE_NUM, MAX_UPWARD_MESSAGE_NUM};
-use primitives::{Balance, SessionIndex, MAX_CODE_SIZE, MAX_HEAD_DATA_SIZE, MAX_POV_SIZE};
+use primitives::{
+	vstaging::AsyncBackingParams, Balance, SessionIndex, MAX_CODE_SIZE, MAX_HEAD_DATA_SIZE,
+	MAX_POV_SIZE,
+};
 use sp_runtime::traits::Zero;
 use sp_std::prelude::*;
 
@@ -118,6 +121,8 @@ pub struct HostConfiguration<BlockNumber> {
 	 * The parameters that are not essential, but still may be of interest for parachains.
 	 */
 
+	/// Asynchronous backing parameters.
+	pub async_backing_params: AsyncBackingParams,
 	/// The maximum POV block size, in bytes.
 	pub max_pov_size: u32,
 	/// The maximum size of a message that can be put in a downward message queue.
@@ -243,6 +248,10 @@ pub struct HostConfiguration<BlockNumber> {
 impl<BlockNumber: Default + From<u32>> Default for HostConfiguration<BlockNumber> {
 	fn default() -> Self {
 		Self {
+			async_backing_params: AsyncBackingParams {
+				max_candidate_depth: 0,
+				allowed_ancestry_len: 0,
+			},
 			group_rotation_frequency: 1u32.into(),
 			chain_availability_period: 1u32.into(),
 			thread_availability_period: 1u32.into(),
@@ -1138,6 +1147,22 @@ pub mod pallet {
 			BypassConsistencyCheck::<T>::put(new);
 			Ok(())
 		}
+
+		/// Set the asynchronous backing parameters.
+		#[pallet::call_index(45)]
+		#[pallet::weight((
+			T::WeightInfo::set_config_with_option_u32(), // The same size in bytes.
+			DispatchClass::Operational,
+		))]
+		pub fn set_async_backing_params(
+			origin: OriginFor<T>,
+			new: AsyncBackingParams,
+		) -> DispatchResult {
+			ensure_root(origin)?;
+			Self::schedule_config_update(|config| {
+				config.async_backing_params = new;
+			})
+		}
 	}
 
 	#[pallet::hooks]