ic_memory/runtime/
mod.rs

1mod admission;
2#[cfg(test)]
3mod admission_tests;
4mod adoption;
5#[cfg(test)]
6mod adoption_tests;
7mod allocations;
8mod backing;
9mod config;
10mod default;
11mod diagnostics;
12mod error;
13mod layout;
14mod policy;
15
16#[cfg(test)]
17mod allocation_tests;
18#[cfg(test)]
19mod growth_tests;
20#[cfg(test)]
21#[expect(
22    unsafe_code,
23    reason = "exercise raw reads with valid uninitialized destinations"
24)]
25mod read_tests;
26#[cfg(test)]
27mod request_tests;
28#[cfg(test)]
29mod tests;
30
31pub use admission::{BootstrapAdmission, BootstrapAdmissionError, RecoveredAllocationMetadata};
32pub use adoption::RuntimeAdoptionError;
33
34pub use allocations::{
35    AllocationBinding, AllocationRangeClaim, MemoryAllocation, MemoryAllocationSummary,
36    MemoryAllocations, MemoryBindingSummary,
37};
38pub use backing::RuntimeMemory;
39pub use config::MemoryManagerConfig;
40pub use default::{
41    bootstrap_default_memory_manager, bootstrap_default_memory_manager_with_config,
42    bootstrap_default_memory_manager_with_policy, committed_allocations,
43    default_memory_manager_commit_recovery_diagnostic, default_memory_manager_diagnostic_export,
44    default_memory_manager_doctor_report, default_memory_manager_doctor_report_with_policy,
45    default_memory_manager_memory_allocation_summary, default_memory_manager_memory_allocations,
46    default_memory_manager_memory_id, is_default_memory_manager_bootstrapped,
47    open_default_memory_manager_memory, open_default_memory_manager_memory_by_key,
48    verify_default_memory_manager_authority,
49};
50pub use error::{
51    MemoryResolutionError, RuntimeBootstrapError, RuntimeConstructionError, RuntimeDiagnosticError,
52    RuntimeGrowError, RuntimeOpenError, RuntimePolicyError, RuntimeStateError,
53};
54pub use layout::MemoryManagerLayoutError;
55pub use policy::GenericRangePolicy;
56
57use self::policy::{RuntimeMemoryManagerPolicy, runtime_bootstrap_error_from_bootstrap};
58use crate::{
59    AllocationBootstrap, AllocationLedger, CommittedAllocations, PolicyIdentity,
60    RuntimeBootstrapPolicy, STABLE_CELL_VALUE_OFFSET, StableCellLedgerError,
61    StableCellLedgerRecord, StableKey, registry::SealedDeclarationSnapshot,
62    slot::MEMORY_MANAGER_LEDGER_ID, stable_cell::decode_stable_cell_ledger_record_from_memory,
63};
64use ic_stable_structures::{
65    Cell, Memory,
66    memory_manager::{MemoryId, MemoryManager},
67};
68
69use std::rc::Rc;
70
71type LedgerCell<M> = Cell<StableCellLedgerRecord, RuntimeMemory<M>>;
72
73enum RuntimeLifecycle {
74    Unbootstrapped,
75    Bootstrapped {
76        committed_allocations: CommittedAllocations,
77        binding: RuntimeBootstrapBinding,
78    },
79}
80
81struct RuntimeBootstrapBinding {
82    source: SealedDeclarationSnapshot,
83    declarations: SealedDeclarationSnapshot,
84    policy_identity: PolicyIdentity,
85}
86
87///
88/// MemoryRuntime
89///
90/// Canonical owner of allocation bootstrap state for one backing memory.
91///
92/// The runtime owns its `MemoryManager`, allocation-ledger cell, bootstrap
93/// lifecycle, committed allocation capability, opens, and diagnostics. Static
94/// linked-program declarations are supplied separately as one immutable
95/// [`SealedDeclarationSnapshot`].
96///
97/// `M` needs only [`Memory`]. The runtime does not require the backing memory
98/// to be `Send`, `Sync`, `Clone`, or `'static`.
99///
100
101pub struct MemoryRuntime<M: Memory> {
102    memory_manager: MemoryManager<Rc<M>>,
103    // Shared backing, immutable geometry and live accounting belong to growth.
104    // Handles reserve physical capacity; the manager owns bucket metadata.
105    growth: Rc<backing::GrowthState<M>>,
106    ledger_cell: Option<LedgerCell<M>>,
107    lifecycle: RuntimeLifecycle,
108}
109
110impl<M: Memory> MemoryRuntime<M> {
111    /// Construct an unbootstrapped runtime without overwriting foreign memory.
112    ///
113    /// Empty backing memory is initialized as an
114    /// `ic_stable_structures::MemoryManager`. Nonempty memory must pass bounded
115    /// validation of the current manager header, bucket table, and extents; otherwise
116    /// construction returns a typed error before the manager can
117    /// write its header or allocation table. A pre-grown blank memory is
118    /// nonempty and is therefore rejected rather than assumed disposable.
119    ///
120    /// # Errors
121    ///
122    /// Returns [`RuntimeConstructionError::ForeignMemory`] for nonempty memory
123    /// without `MemoryManager` magic, or
124    /// [`RuntimeConstructionError::UnsupportedMemoryManagerVersion`] when the
125    /// magic is recognized but the layout version is not current. Invalid
126    /// metadata returns [`RuntimeConstructionError::Layout`]. Refused fresh
127    /// metadata growth returns [`RuntimeConstructionError::Growth`] without
128    /// writes, allowing the same backing memory to be retried. Reopening honors
129    /// the actual persisted bucket size; only fresh memory uses 128 pages.
130    pub fn new(memory: M) -> Result<Self, RuntimeConstructionError> {
131        Self::construct(memory, None)
132    }
133
134    /// Construct with an explicit immutable bucket policy. Existing memory must
135    /// match exactly; mismatches fail before manager initialization or writes.
136    ///
137    /// # Errors
138    ///
139    /// Returns the construction errors described by [`Self::new`], or
140    /// [`RuntimeConstructionError::BucketSizeMismatch`] when existing geometry
141    /// differs from `config`.
142    pub fn new_with_config(
143        memory: M,
144        config: MemoryManagerConfig,
145    ) -> Result<Self, RuntimeConstructionError> {
146        Self::construct(memory, Some(config))
147    }
148
149    fn construct(
150        memory: M,
151        requested: Option<MemoryManagerConfig>,
152    ) -> Result<Self, RuntimeConstructionError> {
153        if cfg!(target_endian = "big") {
154            return Err(MemoryManagerLayoutError::UnsupportedByteOrder.into());
155        }
156        let (bucket_size_pages, allocated_buckets) = if memory.size() == 0 {
157            // Reserve the metadata page before the dependency writes its header.
158            // This fresh allocation is owned here; caller-supplied nonempty
159            // memory still passes the layout checks below before any writes.
160            if memory.grow(1) == -1 {
161                return Err(RuntimeGrowError::BackingRefused {
162                    additional_pages: 1,
163                }
164                .into());
165            }
166            (requested.unwrap_or_default().bucket_size_pages(), 0)
167        } else {
168            let measured = layout::read(&memory)?;
169            let actual = measured.bucket_pages;
170            if let Some(config) = requested {
171                check_bucket_size(actual, config)?;
172            }
173            (actual, measured.allocated_buckets)
174        };
175        let backing = Rc::new(memory);
176        let growth = Rc::new(backing::GrowthState {
177            backing: Rc::clone(&backing),
178            bucket_size_pages,
179            allocated_buckets: std::cell::RefCell::new(allocated_buckets),
180        });
181        Ok(Self {
182            memory_manager: MemoryManager::init_with_bucket_size(
183                Rc::clone(&backing),
184                bucket_size_pages,
185            ),
186            growth,
187            ledger_cell: None,
188            lifecycle: RuntimeLifecycle::Unbootstrapped,
189        })
190    }
191
192    /// Return the immutable bucket configuration bound to this runtime's manager.
193    #[must_use]
194    pub fn memory_manager_config(&self) -> MemoryManagerConfig {
195        // Construction has already validated the nonzero persisted setting.
196        MemoryManagerConfig::from_validated(self.growth.bucket_size_pages)
197    }
198
199    /// Return whether this runtime has published committed allocation authority.
200    #[must_use]
201    pub const fn is_bootstrapped(&self) -> bool {
202        matches!(self.lifecycle, RuntimeLifecycle::Bootstrapped { .. })
203    }
204
205    /// Bootstrap this backing memory from one immutable declaration snapshot.
206    ///
207    /// Recovery, metadata admission, logical resolution, policy evaluation,
208    /// staging, persistence and capability publication are local to this runtime.
209    /// A repeated call is idempotent only when the sealed declaration snapshot and
210    /// [`RuntimeBootstrapPolicy::runtime_bootstrap_identity`] match the
211    /// successful bootstrap. A mismatch returns a typed error without
212    /// advancing the durable generation or re-evaluating policy.
213    /// Independently sealed snapshots match when their canonical contents are equal.
214    ///
215    /// # Panics
216    ///
217    /// Panics if a private runtime or encoding invariant is broken, or backing
218    /// memory or a policy callback panics.
219    pub fn bootstrap<P: RuntimeBootstrapPolicy>(
220        &mut self,
221        declarations: &SealedDeclarationSnapshot,
222        policy: &P,
223    ) -> Result<&CommittedAllocations, RuntimeBootstrapError<P::Error>> {
224        let policy_identity = policy.runtime_bootstrap_identity()?;
225        let already_bootstrapped = match &self.lifecycle {
226            RuntimeLifecycle::Unbootstrapped => false,
227            RuntimeLifecycle::Bootstrapped { binding, .. } => {
228                binding.validate(declarations, &policy_identity)?;
229                true
230            }
231        };
232        if !already_bootstrapped {
233            self.bootstrap_unbootstrapped(declarations, policy, policy_identity)?;
234        }
235        match &self.lifecycle {
236            RuntimeLifecycle::Bootstrapped {
237                committed_allocations,
238                ..
239            } => Ok(committed_allocations),
240            RuntimeLifecycle::Unbootstrapped => {
241                unreachable!("successful bootstrap publishes committed allocations")
242            }
243        }
244    }
245
246    fn bootstrap_unbootstrapped<P: RuntimeBootstrapPolicy>(
247        &mut self,
248        declarations: &SealedDeclarationSnapshot,
249        policy: &P,
250        policy_identity: PolicyIdentity,
251    ) -> Result<(), RuntimeBootstrapError<P::Error>> {
252        self.initialize_ledger_cell()?;
253        let mut record = self
254            .ledger_cell
255            .as_ref()
256            .expect("successful ledger initialization establishes the cell")
257            .get()
258            .clone();
259        let genesis = AllocationLedger::empty_genesis();
260        let recovered = record.store_mut().recover_or_initialize(&genesis)?;
261        let mut admission = BootstrapAdmission::new(recovered.ledger(), declarations);
262        let preparation = policy.prepare_bootstrap(&mut admission);
263        let historical = admission.complete()?;
264        preparation.map_err(RuntimeBootstrapError::AdmissionPolicy)?;
265        let resolved = declarations.resolve(recovered.ledger(), historical)?;
266        let runtime_policy = RuntimeMemoryManagerPolicy {
267            declarations: &resolved,
268            custom_policy: policy,
269        };
270        let commit = AllocationBootstrap::new(record.store_mut())
271            .validate_against(
272                recovered,
273                resolved.allocation_snapshot().clone(),
274                &runtime_policy,
275                None,
276            )
277            .map_err(runtime_bootstrap_error_from_bootstrap)?;
278        self.persist_ledger_record(record)?;
279        let committed = commit.confirm_persisted().into_application_allocations();
280        self.lifecycle = RuntimeLifecycle::Bootstrapped {
281            committed_allocations: committed,
282            binding: RuntimeBootstrapBinding {
283                source: declarations.clone(),
284                declarations: resolved,
285                policy_identity,
286            },
287        };
288        Ok(())
289    }
290
291    /// Borrow this runtime's committed allocation-open capability.
292    pub const fn committed_allocations(&self) -> Result<&CommittedAllocations, RuntimeOpenError> {
293        match &self.lifecycle {
294            RuntimeLifecycle::Unbootstrapped => Err(RuntimeOpenError::NotBootstrapped),
295            RuntimeLifecycle::Bootstrapped {
296                committed_allocations,
297                ..
298            } => Ok(committed_allocations),
299        }
300    }
301
302    /// Open by durable key using only this runtime's persisted current capability.
303    pub fn open_memory_by_key(
304        &self,
305        stable_key: &str,
306    ) -> Result<RuntimeMemory<M>, RuntimeOpenError> {
307        Ok(self.memory(self.memory_id(stable_key)?))
308    }
309
310    /// Open this runtime's committed memory by stable key and expected ID.
311    pub fn open_memory(
312        &self,
313        stable_key: &str,
314        expected_id: u8,
315    ) -> Result<RuntimeMemory<M>, RuntimeOpenError> {
316        let committed_id = self.memory_id(stable_key)?;
317        if committed_id != expected_id {
318            return Err(RuntimeOpenError::MemoryIdMismatch {
319                stable_key: stable_key.to_string(),
320                committed_id,
321                requested_id: expected_id,
322            });
323        }
324        Ok(self.memory(committed_id))
325    }
326
327    /// Resolve an application key's committed ID without opening memory,
328    /// reading history, or changing the host's policy or bucket configuration.
329    ///
330    /// # Panics
331    ///
332    /// Panics only if an internal committed-allocation invariant is broken.
333    pub fn memory_id(&self, stable_key: &str) -> Result<u8, RuntimeOpenError> {
334        let key = StableKey::parse(stable_key)?;
335        if crate::is_ic_memory_stable_key(key.as_str()) {
336            return Err(RuntimeOpenError::ReservedStableKey {
337                stable_key: stable_key.to_string(),
338            });
339        }
340        let slot = self
341            .committed_allocations()?
342            .slot_for(&key)
343            .ok_or_else(|| RuntimeOpenError::StableKeyNotCommitted(stable_key.to_string()))?;
344        Ok(slot.memory_manager_id().expect("committed allocation slot"))
345    }
346
347    fn initialize_ledger_cell<P>(&mut self) -> Result<(), RuntimeBootstrapError<P>> {
348        if self.ledger_cell.is_some() {
349            return Ok(());
350        }
351        let memory = self.memory(MEMORY_MANAGER_LEDGER_ID);
352        crate::validate_stable_cell_ledger_memory(&memory)?;
353        ensure_ledger_cell_capacity(&memory, &StableCellLedgerRecord::default())?;
354        self.ledger_cell = Some(Cell::init(memory, StableCellLedgerRecord::default()));
355        Ok(())
356    }
357
358    fn persist_ledger_record<P>(
359        &mut self,
360        record: StableCellLedgerRecord,
361    ) -> Result<(), RuntimeBootstrapError<P>> {
362        let memory = self.memory(MEMORY_MANAGER_LEDGER_ID);
363        ensure_ledger_cell_capacity(&memory, &record)?;
364        let cell = self
365            .ledger_cell
366            .as_mut()
367            .expect("ledger persistence follows successful initialization");
368        let _previous = cell.set(record);
369        Ok(())
370    }
371
372    fn memory(&self, id: u8) -> RuntimeMemory<M> {
373        RuntimeMemory {
374            memory: self.memory_manager.get(MemoryId::new(id)),
375            growth: Rc::clone(&self.growth),
376        }
377    }
378
379    fn ledger_record_from_memory(&self) -> Result<StableCellLedgerRecord, StableCellLedgerError> {
380        decode_stable_cell_ledger_record_from_memory(&self.memory(MEMORY_MANAGER_LEDGER_ID))
381    }
382}
383
384impl RuntimeBootstrapBinding {
385    fn validate<P>(
386        &self,
387        declarations: &SealedDeclarationSnapshot,
388        policy_identity: &PolicyIdentity,
389    ) -> Result<(), RuntimeBootstrapError<P>> {
390        if &self.source != declarations {
391            return Err(RuntimeBootstrapError::DeclarationSnapshotMismatch);
392        }
393        if &self.policy_identity != policy_identity {
394            return Err(RuntimeBootstrapError::PolicyIdentityMismatch {
395                established: self.policy_identity.clone(),
396                requested: policy_identity.clone(),
397            });
398        }
399        Ok(())
400    }
401}
402
403fn ensure_ledger_cell_capacity<M: Memory, P>(
404    memory: &RuntimeMemory<M>,
405    record: &StableCellLedgerRecord,
406) -> Result<(), RuntimeBootstrapError<P>> {
407    let value_size = record.encoded_size();
408    if value_size > crate::constants::MAX_LEDGER_RECORD_BYTES {
409        return Err(RuntimeBootstrapError::StableCellLedgerWriteTooLarge { value_size });
410    }
411    // The record limit is below u32::MAX, including the eight-byte cell header.
412    let required_bytes = STABLE_CELL_VALUE_OFFSET + value_size as u64;
413    let available_bytes = memory.size().saturating_mul(crate::WASM_PAGE_SIZE_BYTES);
414    if required_bytes <= available_bytes {
415        return Ok(());
416    }
417    let grow_by = (required_bytes - available_bytes).div_ceil(crate::WASM_PAGE_SIZE_BYTES);
418    memory.grow(grow_by)?;
419    Ok(())
420}
421
422const fn check_bucket_size(
423    actual: u16,
424    requested: MemoryManagerConfig,
425) -> Result<(), RuntimeConstructionError> {
426    if actual != requested.bucket_size_pages() {
427        return Err(RuntimeConstructionError::BucketSizeMismatch {
428            persisted: actual,
429            requested: requested.bucket_size_pages(),
430        });
431    }
432    Ok(())
433}
ic_memory/runtime/mod.rs

ic_memory/runtime/
mod.rs
