feat: enable and disable flashloans

.gitignore

@@ -18,4 +18,6 @@ coverage
 .coverage_cache
 .coverage_contracts
 coverage.json
-deployments/
+deployments/
+
+.DS_Store

contracts/deployments/ReservesSetupHelper.sol

@@ -21,6 +21,7 @@ contract ReservesSetupHelper is Ownable {
     uint256 supplyCap;
     bool stableBorrowingEnabled;
     bool borrowingEnabled;
+    bool flashLoanEnabled;
   }
 
   /**
@@ -43,6 +44,7 @@ contract ReservesSetupHelper is Ownable {
 
       if (inputParams[i].borrowingEnabled) {
         configurator.setReserveBorrowing(inputParams[i].asset, true);
+        configurator.setReserveFlashLoaning(inputParams[i].asset, inputParams[i].flashLoanEnabled);
 
         configurator.setBorrowCap(inputParams[i].asset, inputParams[i].borrowCap);
         configurator.setReserveStableRateBorrowing(

contracts/interfaces/IPoolConfigurator.sol

@@ -32,6 +32,13 @@ interface IPoolConfigurator {
    **/
   event ReserveBorrowing(address indexed asset, bool enabled);
 
+  /**
+   * @dev Emitted when flashloans are enabled or disabled on a reserve.
+   * @param asset The address of the underlying asset of the reserve
+   * @param enabled True if flashloans are enabled, False if flashloans are disabled
+   */
+  event ReserveFlashLoaning(address indexed asset, bool enabled);
+
   /**
    * @dev Emitted when the collateralization risk parameters for the specified asset are updated.
    * @param asset The address of the underlying asset of the reserve
@@ -310,6 +317,14 @@ interface IPoolConfigurator {
    **/
   function setReserveStableRateBorrowing(address asset, bool enabled) external;
 
+  /**
+   * @notice Configures flashloans on a reserve
+   * @dev Can only be enabled (set to true) if borrowing is enabled
+   * @param asset The address of the underlying asset of the reserve
+   * @param enabled True if flashloans need to be enabled, false to disable falshloans
+   */
+  function setReserveFlashLoaning(address asset, bool enabled) external;
+
   /**
    * @notice Activate or deactivate a reserve
    * @param asset The address of the underlying asset of the reserve

contracts/protocol/libraries/configuration/ReserveConfiguration.sol

@@ -28,6 +28,7 @@ library ReserveConfiguration {
   uint256 internal constant EMODE_CATEGORY_MASK =            0xFFFFFFFFFFFFFFFFFFFF00FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF; // prettier-ignore
   uint256 internal constant UNBACKED_MINT_CAP_MASK =         0xFFFFFFFFFFF000000000FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF; // prettier-ignore
   uint256 internal constant DEBT_CEILING_MASK =              0xF0000000000FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF; // prettier-ignore
+  uint256 internal constant FLASHLOAN_ENABLED_MASK =         0xEFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF; // prettier-ignore
 
   /// @dev For the LTV, the start bit is 0 (up to 15), hence no bitshifting is needed
   uint256 internal constant LIQUIDATION_THRESHOLD_START_BIT_POSITION = 16;
@@ -49,6 +50,7 @@ library ReserveConfiguration {
   uint256 internal constant EMODE_CATEGORY_START_BIT_POSITION = 168;
   uint256 internal constant UNBACKED_MINT_CAP_START_BIT_POSITION = 176;
   uint256 internal constant DEBT_CEILING_START_BIT_POSITION = 212;
+  uint256 internal constant FLASHLOAN_ENABLED_START_BIT_POSITION = 252;
 
   uint256 internal constant MAX_VALID_LTV = 65535;
   uint256 internal constant MAX_VALID_LIQUIDATION_THRESHOLD = 65535;
@@ -547,6 +549,32 @@ library ReserveConfiguration {
     return (self.data & ~EMODE_CATEGORY_MASK) >> EMODE_CATEGORY_START_BIT_POSITION;
   }
 
+  /**
+   * @dev Set whether or not FlashLoaning this asset is enabled
+   * @param self The reserve configuration
+   * @param flashLoanEnabled boolean to indicated if Flashloans should be enabled (1) or disabled (0)
+   */
+  function setFlashLoanEnabled(DataTypes.ReserveConfigurationMap memory self, bool flashLoanEnabled)
+    internal
+    pure
+  {
+    self.data =
+      (self.data & FLASHLOAN_ENABLED_MASK) |
+      (uint256(flashLoanEnabled ? 1 : 0) << FLASHLOAN_ENABLED_START_BIT_POSITION);
+  }
+
+  /**
+   * @dev Get the flashLoanEnabledSetting
+   * @param self The reserve configuration
+   */
+  function getFlashLoanEnabled(DataTypes.ReserveConfigurationMap memory self)
+    internal
+    pure
+    returns (bool)
+  {
+    return (self.data & ~FLASHLOAN_ENABLED_MASK) != 0;
+  }
+
   /**
    * @notice Gets the configuration flags of the reserve
    * @param self The reserve configuration

contracts/protocol/libraries/helpers/Errors.sol

@@ -97,4 +97,5 @@ library Errors {
   string public constant STABLE_BORROWING_ENABLED = '88'; // 'Stable borrowing is enabled'
   string public constant SILOED_BORROWING_VIOLATION = '89'; // 'User is trying to borrow multiple assets including a siloed one'
   string public constant RESERVE_DEBT_NOT_ZERO = '90'; // the total debt of the reserve needs to be 0
+  string public constant FLASHLOAN_DISABLED = '91'; // FlashLoaning for this asset is disabled
 }

contracts/protocol/libraries/logic/ValidationLogic.sol

@@ -472,6 +472,7 @@ library ValidationLogic {
         .configuration;
       require(!configuration.getPaused(), Errors.RESERVE_PAUSED);
       require(configuration.getActive(), Errors.RESERVE_INACTIVE);
+      require(configuration.getFlashLoanEnabled(), Errors.FLASHLOAN_DISABLED);
     }
   }
 

contracts/protocol/pool/PoolConfigurator.sol

@@ -69,7 +69,7 @@ contract PoolConfigurator is VersionedInitializable, IPoolConfigurator {
   uint256 public constant CONFIGURATOR_REVISION = 0x1;
 
   /// @inheritdoc VersionedInitializable
-  function getRevision() internal pure virtual override returns (uint256) {
+  function getRevision() internal virtual override pure returns (uint256) {
     return CONFIGURATOR_REVISION;
   }
 
@@ -191,6 +191,22 @@ contract PoolConfigurator is VersionedInitializable, IPoolConfigurator {
     emit ReserveStableRateBorrowing(asset, enabled);
   }
 
+  /// @inheritdoc IPoolConfigurator
+  function setReserveFlashLoaning(address asset, bool enabled)
+    external
+    override
+    onlyRiskOrPoolAdmins
+  {
+    DataTypes.ReserveConfigurationMap memory currentConfig = _pool.getConfiguration(asset);
+
+    if (enabled) {
+      require(currentConfig.getBorrowingEnabled(), Errors.BORROWING_NOT_ENABLED);
+    }
+    currentConfig.setFlashLoanEnabled(enabled);
+    _pool.setConfiguration(asset, currentConfig);
+    emit ReserveFlashLoaning(asset, enabled);
+  }
+
   /// @inheritdoc IPoolConfigurator
   function setReserveActive(address asset, bool active) external override onlyPoolAdmin {
     if (!active) _checkNoSuppliers(asset);