Syscall: GetEpochStake

program-runtime/src/invoke_context.rs

@@ -169,6 +169,7 @@ pub struct InvokeContext<'a> {
     pub programs_loaded_for_tx_batch: &'a ProgramCacheForTxBatch,
     pub programs_modified_by_tx: &'a mut ProgramCacheForTxBatch,
     pub feature_set: Arc<FeatureSet>,
+    pub get_epoch_stake_callback: &'a dyn Fn(&'a Pubkey) -> u64,
     pub timings: ExecuteDetailsTimings,
     pub blockhash: Hash,
     pub lamports_per_signature: u64,
@@ -186,6 +187,7 @@ impl<'a> InvokeContext<'a> {
         programs_loaded_for_tx_batch: &'a ProgramCacheForTxBatch,
         programs_modified_by_tx: &'a mut ProgramCacheForTxBatch,
         feature_set: Arc<FeatureSet>,
+        get_epoch_stake_callback: &'a dyn Fn(&'a Pubkey) -> u64,
         blockhash: Hash,
         lamports_per_signature: u64,
     ) -> Self {
@@ -199,6 +201,7 @@ impl<'a> InvokeContext<'a> {
             programs_loaded_for_tx_batch,
             programs_modified_by_tx,
             feature_set,
+            get_epoch_stake_callback,
             timings: ExecuteDetailsTimings::default(),
             blockhash,
             lamports_per_signature,
@@ -685,6 +688,7 @@ macro_rules! with_mock_invoke_context {
             &programs_loaded_for_tx_batch,
             &mut programs_modified_by_tx,
             Arc::new(FeatureSet::all_enabled()),
+            &|_| 0,
             Hash::default(),
             0,
         );

programs/bpf_loader/src/syscalls/mod.rs

@@ -38,8 +38,9 @@ use {
             disable_deploy_of_alloc_free_syscall, disable_fees_sysvar,
             enable_alt_bn128_compression_syscall, enable_alt_bn128_syscall,
             enable_big_mod_exp_syscall, enable_partitioned_epoch_reward, enable_poseidon_syscall,
-            error_on_syscall_bpf_function_hash_collisions, last_restart_slot_sysvar,
-            reject_callx_r10, remaining_compute_units_syscall_enabled, switch_to_new_elf_parser,
+            enable_syscall_get_epoch_stake, error_on_syscall_bpf_function_hash_collisions,
+            last_restart_slot_sysvar, reject_callx_r10, remaining_compute_units_syscall_enabled,
+            switch_to_new_elf_parser,
         },
         hash::{Hash, Hasher},
         instruction::{AccountMeta, InstructionError, ProcessedSiblingInstruction},
@@ -278,6 +279,8 @@ pub fn create_program_runtime_environment_v1<'a>(
     let enable_poseidon_syscall = feature_set.is_active(&enable_poseidon_syscall::id());
     let remaining_compute_units_syscall_enabled =
         feature_set.is_active(&remaining_compute_units_syscall_enabled::id());
+    let enable_syscall_get_epoch_stake =
+        feature_set.is_active(&enable_syscall_get_epoch_stake::id());
     // !!! ATTENTION !!!
     // When adding new features for RBPF here,
     // also add them to `Bank::apply_builtin_program_feature_transitions()`.
@@ -464,6 +467,14 @@ pub fn create_program_runtime_environment_v1<'a>(
         SyscallAltBn128Compression::vm,
     )?;
 
+    // Get Epoch Stake
+    register_feature_gated_function!(
+        result,
+        enable_syscall_get_epoch_stake,
+        *b"sol_syscall_get_epoch_stake",
+        SyscallGetEpochStake::vm,
+    )?;
+
     // Log data
     result.register_function_hashed(*b"sol_log_data", SyscallLogData::vm)?;
 
@@ -1997,6 +2008,37 @@ declare_builtin_function!(
     }
 );
 
+declare_builtin_function!(
+    // Get Epoch Stake Syscall
+    SyscallGetEpochStake,
+    fn rust(
+        invoke_context: &mut InvokeContext,
+        var_addr: u64,
+        vote_address: u64,
+        _arg3: u64,
+        _arg4: u64,
+        _arg5: u64,
+        memory_mapping: &mut MemoryMapping,
+    ) -> Result<u64, Error> {
+        let compute_budget = invoke_context.get_compute_budget();
+        let div_by_cpi = |n: u64| -> u64 {
+            n.checked_div(compute_budget.cpi_bytes_per_unit)
+                .unwrap_or(u64::MAX)
+        };
+        consume_compute_meter(invoke_context, div_by_cpi(32).saturating_add(div_by_cpi(8)))?;
+
+        let check_aligned = invoke_context.get_check_aligned();
+
+        let vote_address = translate_type::<Pubkey>(memory_mapping, vote_address, check_aligned)?;
+
+        let var = translate_type_mut::<u64>(memory_mapping, var_addr, check_aligned)?;
+
+        *var = (invoke_context.get_epoch_stake_callback)(vote_address);
+
+        Ok(0)
+    }
+);
+
 #[cfg(test)]
 #[allow(clippy::arithmetic_side_effects)]
 #[allow(clippy::indexing_slicing)]

runtime/src/bank.rs

@@ -6804,6 +6804,10 @@ impl TransactionProcessingCallback for Bank {
         self.feature_set.clone()
     }
 
+    fn get_epoch_stake(&self, vote_address: &Pubkey) -> u64 {
+        self.epoch_vote_account_stake(vote_address)
+    }
+
     fn get_program_match_criteria(&self, program: &Pubkey) -> ProgramCacheMatchCriteria {
         if self.check_program_modification_slot {
             self.program_modification_slot(program)

runtime/src/bank/builtins/core_bpf_migration/mod.rs

@@ -180,6 +180,7 @@ impl Bank {
                 &programs_loaded,
                 &mut programs_modified,
                 self.feature_set.clone(),
+                &|_| 0,
                 Hash::default(),
                 0,
             );

sdk/program/src/epoch_stake.rs

@@ -0,0 +1,21 @@
+use crate::{program_error::ProgramError, pubkey::Pubkey};
+
+/// Get the current epoch stake for a given vote account.
+/// Returns `0` for any provided pubkey that isn't a vote account.
+pub fn get_epoch_stake(vote_address: &Pubkey) -> Result<u64, ProgramError> {
+    let mut var = 0u64;
+    let var_addr = &mut var as *mut _ as *mut u8;
+
+    let vote_address = vote_address as *const _ as *const u8;
+
+    #[cfg(target_os = "solana")]
+    let result = unsafe { crate::syscalls::sol_syscall_get_epoch_stake(var_addr, vote_address) };
+
+    #[cfg(not(target_os = "solana"))]
+    let result = crate::program_stubs::sol_syscall_get_epoch_stake(var_addr, vote_address);
+
+    match result {
+        crate::entrypoint::SUCCESS => Ok(var),
+        e => Err(e.into()),
+    }
+}

sdk/program/src/lib.rs

@@ -491,6 +491,7 @@ pub mod entrypoint;
 pub mod entrypoint_deprecated;
 pub mod epoch_rewards;
 pub mod epoch_schedule;
+pub mod epoch_stake;
 pub mod feature;
 pub mod fee_calculator;
 pub mod hash;

sdk/program/src/program_stubs.rs

@@ -61,6 +61,9 @@ pub trait SyscallStubs: Sync + Send {
     fn sol_get_last_restart_slot(&self, _var_addr: *mut u8) -> u64 {
         UNSUPPORTED_SYSVAR
     }
+    fn sol_syscall_get_epoch_stake(&self, _var_addr: *mut u8, _vote_address: *const u8) -> u64 {
+        UNSUPPORTED_SYSVAR
+    }
     /// # Safety
     unsafe fn sol_memcpy(&self, dst: *mut u8, src: *const u8, n: usize) {
         // cannot be overlapping
@@ -171,6 +174,13 @@ pub(crate) fn sol_get_last_restart_slot(var_addr: *mut u8) -> u64 {
         .sol_get_last_restart_slot(var_addr)
 }
 
+pub(crate) fn sol_syscall_get_epoch_stake(var_addr: *mut u8, vote_address: *const u8) -> u64 {
+    SYSCALL_STUBS
+        .read()
+        .unwrap()
+        .sol_syscall_get_epoch_stake(var_addr, vote_address)
+}
+
 pub(crate) fn sol_memcpy(dst: *mut u8, src: *const u8, n: usize) {
     unsafe {
         SYSCALL_STUBS.read().unwrap().sol_memcpy(dst, src, n);

sdk/program/src/syscalls/definitions.rs

@@ -72,6 +72,7 @@ define_syscall!(fn sol_get_epoch_rewards_sysvar(addr: *mut u8) -> u64);
 define_syscall!(fn sol_poseidon(parameters: u64, endianness: u64, vals: *const u8, val_len: u64, hash_result: *mut u8) -> u64);
 define_syscall!(fn sol_remaining_compute_units() -> u64);
 define_syscall!(fn sol_alt_bn128_compression(op: u64, input: *const u8, input_size: u64, result: *mut u8) -> u64);
+define_syscall!(fn sol_syscall_get_epoch_stake(addr: *mut u8, vote_address: *const u8) -> u64);
 
 #[cfg(target_feature = "static-syscalls")]
 pub const fn sys_hash(name: &str) -> usize {

sdk/src/feature_set.rs

@@ -801,6 +801,10 @@ pub mod abort_on_invalid_curve {
     solana_sdk::declare_id!("FuS3FPfJDKSNot99ECLXtp3rueq36hMNStJkPJwWodLh");
 }
 
+pub mod enable_syscall_get_epoch_stake {
+    solana_sdk::declare_id!("7mScTYkJXsbdrcwTQRs7oeCSXoJm4WjzBsRyf8bCU3Np");
+}
+
 lazy_static! {
     /// Map of feature identifiers to user-visible description
     pub static ref FEATURE_NAMES: HashMap<Pubkey, &'static str> = [
@@ -995,7 +999,8 @@ lazy_static! {
         (enable_tower_sync_ix::id(), "Enable tower sync vote instruction"),
         (chained_merkle_conflict_duplicate_proofs::id(), "generate duplicate proofs for chained merkle root conflicts"),
         (reward_full_priority_fee::id(), "Reward full priority fee to validators #34731"),
-        (abort_on_invalid_curve::id(), "Abort when elliptic curve syscalls invoked on invalid curve id SIMD-0137")
+        (abort_on_invalid_curve::id(), "Abort when elliptic curve syscalls invoked on invalid curve id SIMD-0137"),
+        (enable_syscall_get_epoch_stake::id(), "Enable syscall: sol_get_epoch_stake #884")
         /*************** ADD NEW FEATURES HERE ***************/
     ]
     .iter()

svm/src/account_loader.rs

@@ -499,6 +499,7 @@ mod tests {
         accounts_map: HashMap<Pubkey, AccountSharedData>,
         rent_collector: RentCollector,
         feature_set: Arc<FeatureSet>,
+        epoch_stake: u64,
     }
 
     impl TransactionProcessingCallback for TestCallbacks {
@@ -521,6 +522,10 @@ mod tests {
         fn get_feature_set(&self) -> Arc<FeatureSet> {
             self.feature_set.clone()
         }
+
+        fn get_epoch_stake(&self, _vote_address: &Pubkey) -> u64 {
+            self.epoch_stake
+        }
     }
 
     fn load_accounts_with_fee_and_rent(
@@ -542,6 +547,7 @@ mod tests {
             accounts_map,
             rent_collector: rent_collector.clone(),
             feature_set: Arc::new(feature_set.clone()),
+            epoch_stake: 0,
         };
         load_accounts(
             &callbacks,
@@ -1030,6 +1036,7 @@ mod tests {
             accounts_map,
             rent_collector: RentCollector::default(),
             feature_set: Arc::new(FeatureSet::all_enabled()),
+            epoch_stake: 0,
         };
         load_accounts(
             &callbacks,

svm/src/message_processor.rs

@@ -280,6 +280,7 @@ mod tests {
             &programs_loaded_for_tx_batch,
             &mut programs_modified_by_tx,
             Arc::new(FeatureSet::all_enabled()),
+            &|_| 0,
             Hash::default(),
             0,
         );
@@ -331,6 +332,7 @@ mod tests {
             &programs_loaded_for_tx_batch,
             &mut programs_modified_by_tx,
             Arc::new(FeatureSet::all_enabled()),
+            &|_| 0,
             Hash::default(),
             0,
         );
@@ -372,6 +374,7 @@ mod tests {
             &programs_loaded_for_tx_batch,
             &mut programs_modified_by_tx,
             Arc::new(FeatureSet::all_enabled()),
+            &|_| 0,
             Hash::default(),
             0,
         );
@@ -504,6 +507,7 @@ mod tests {
             &programs_loaded_for_tx_batch,
             &mut programs_modified_by_tx,
             Arc::new(FeatureSet::all_enabled()),
+            &|_| 0,
             Hash::default(),
             0,
         );
@@ -540,6 +544,7 @@ mod tests {
             &programs_loaded_for_tx_batch,
             &mut programs_modified_by_tx,
             Arc::new(FeatureSet::all_enabled()),
+            &|_| 0,
             Hash::default(),
             0,
         );
@@ -573,6 +578,7 @@ mod tests {
             &programs_loaded_for_tx_batch,
             &mut programs_modified_by_tx,
             Arc::new(FeatureSet::all_enabled()),
+            &|_| 0,
             Hash::default(),
             0,
         );
@@ -667,6 +673,7 @@ mod tests {
             &programs_loaded_for_tx_batch,
             &mut programs_modified_by_tx,
             Arc::new(FeatureSet::all_enabled()),
+            &|_| 0,
             Hash::default(),
             0,
         );

svm/src/program_loader.rs

@@ -270,6 +270,7 @@ mod tests {
     pub struct MockBankCallback {
         rent_collector: RentCollector,
         feature_set: Arc<FeatureSet>,
+        epoch_stake: u64,
         pub account_shared_data: RefCell<HashMap<Pubkey, AccountSharedData>>,
     }
 
@@ -302,6 +303,10 @@ mod tests {
             self.feature_set.clone()
         }
 
+        fn get_epoch_stake(&self, _vote_address: &Pubkey) -> u64 {
+            self.epoch_stake
+        }
+
         fn add_builtin_account(&self, name: &str, program_id: &Pubkey) {
             let mut account_data = AccountSharedData::default();
             account_data.set_data(name.as_bytes().to_vec());

svm/src/transaction_processing_callback.rs

@@ -19,6 +19,8 @@ pub trait TransactionProcessingCallback {
 
     fn get_feature_set(&self) -> Arc<FeatureSet>;
 
+    fn get_epoch_stake(&self, vote_address: &Pubkey) -> u64;
+
     fn get_program_match_criteria(&self, _program: &Pubkey) -> ProgramCacheMatchCriteria {
         ProgramCacheMatchCriteria::NoCriteria
     }

svm/src/transaction_processor.rs

@@ -531,6 +531,7 @@ impl<FG: ForkGraph> TransactionBatchProcessor<FG> {
             programs_loaded_for_tx_batch.latest_root_epoch,
         );
         let sysvar_cache = &self.sysvar_cache.read().unwrap();
+        let epoch_stake_callback = |pubkey| callback.get_epoch_stake(pubkey);
 
         let mut invoke_context = InvokeContext::new(
             &mut transaction_context,
@@ -540,6 +541,7 @@ impl<FG: ForkGraph> TransactionBatchProcessor<FG> {
             programs_loaded_for_tx_batch,
             &mut programs_modified_by_tx,
             callback.get_feature_set(),
+            &epoch_stake_callback,
             blockhash,
             lamports_per_signature,
         );
@@ -783,6 +785,7 @@ mod tests {
     pub struct MockBankCallback {
         rent_collector: RentCollector,
         feature_set: Arc<FeatureSet>,
+        epoch_stake: u64,
         pub account_shared_data: RefCell<HashMap<Pubkey, AccountSharedData>>,
     }
 
@@ -815,6 +818,10 @@ mod tests {
             self.feature_set.clone()
         }
 
+        fn get_epoch_stake(&self, _vote_address: &Pubkey) -> u64 {
+            self.epoch_stake
+        }
+
         fn add_builtin_account(&self, name: &str, program_id: &Pubkey) {
             let mut account_data = AccountSharedData::default();
             account_data.set_data(name.as_bytes().to_vec());

svm/tests/mock_bank.rs

@@ -15,6 +15,7 @@ use {
 pub struct MockBankCallback {
     rent_collector: RentCollector,
     feature_set: Arc<FeatureSet>,
+    epoch_stake: u64,
     pub account_shared_data: RefCell<HashMap<Pubkey, AccountSharedData>>,
 }
 
@@ -48,6 +49,10 @@ impl TransactionProcessingCallback for MockBankCallback {
         self.feature_set.clone()
     }
 
+    fn get_epoch_stake(&self, _vote_address: &Pubkey) -> u64 {
+        self.epoch_stake
+    }
+
     fn add_builtin_account(&self, name: &str, program_id: &Pubkey) {
         let account_data = native_loader::create_loadable_account_with_fields(name, (5000, 0));