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, MemoryAllocation, MemoryAllocationSummary, MemoryAllocations,
36    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, verify_default_memory_manager_authority,
48};
49pub use error::{
50    MemoryResolutionError, RuntimeBootstrapError, RuntimeConstructionError, RuntimeDiagnosticError,
51    RuntimeGrowError, RuntimeOpenError, RuntimeStateError,
52};
53pub use layout::MemoryManagerLayoutError;
54pub use policy::GenericAllocationPolicy;
55
56use self::policy::{RuntimeMemoryManagerPolicy, runtime_bootstrap_error_from_bootstrap};
57use crate::{
58    AllocationBootstrap, AllocationLedger, CommittedAllocations, PolicyIdentity,
59    RuntimeBootstrapPolicy, STABLE_CELL_VALUE_OFFSET, StableCellLedgerError,
60    StableCellLedgerRecord, registry::SealedDeclarationSnapshot, slot::MEMORY_MANAGER_LEDGER_ID,
61    stable_cell::decode_stable_cell_ledger_record_from_memory,
62};
63use ic_stable_structures::{
64    Cell, Memory,
65    memory_manager::{MemoryId, MemoryManager},
66};
67
68use std::rc::Rc;
69
70enum RuntimeLifecycle {
71    Unbootstrapped,
72    Bootstrapped {
73        committed_allocations: CommittedAllocations,
74        binding: RuntimeBootstrapBinding,
75    },
76}
77
78struct RuntimeBootstrapBinding {
79    source: SealedDeclarationSnapshot,
80    policy_identity: PolicyIdentity,
81    pool: crate::MemoryAllocationPool,
82}
83
84///
85/// MemoryRuntime
86///
87/// Canonical owner of allocation bootstrap state for one backing memory.
88///
89/// The runtime owns its `MemoryManager`, allocation-ledger persistence, bootstrap
90/// lifecycle, committed allocation capability, opens, and diagnostics. Static
91/// linked-program declarations are supplied separately as one immutable
92/// [`SealedDeclarationSnapshot`].
93///
94/// Each bootstrap attempt fallibly decodes its ledger record from persisted
95/// memory. Capacity-checked writes use `Cell`; diagnostics also read persisted
96/// memory directly.
97///
98/// `M` needs only [`Memory`]. The runtime does not require the backing memory
99/// to be `Send`, `Sync`, `Clone`, or `'static`.
100///
101
102pub struct MemoryRuntime<M: Memory> {
103    memory_manager: MemoryManager<Rc<M>>,
104    // Shared backing, immutable geometry and live accounting belong to growth.
105    // Handles reserve physical capacity; the manager owns bucket metadata.
106    growth: Rc<backing::GrowthState<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            lifecycle: RuntimeLifecycle::Unbootstrapped,
188        })
189    }
190
191    /// Return the immutable bucket configuration bound to this runtime's manager.
192    #[must_use]
193    pub fn memory_manager_config(&self) -> MemoryManagerConfig {
194        // Construction has already validated the nonzero persisted setting.
195        MemoryManagerConfig::from_validated(self.growth.bucket_size_pages)
196    }
197
198    /// Return whether this runtime has published committed allocation authority.
199    #[must_use]
200    pub const fn is_bootstrapped(&self) -> bool {
201        matches!(self.lifecycle, RuntimeLifecycle::Bootstrapped { .. })
202    }
203
204    /// Bootstrap this backing memory from one immutable declaration snapshot.
205    ///
206    /// Recovery, metadata admission, logical resolution, policy evaluation,
207    /// staging, persistence and capability publication are local to this runtime.
208    /// A repeated call is idempotent only when the sealed declaration snapshot,
209    /// canonical host pool and [`RuntimeBootstrapPolicy::runtime_bootstrap_identity`] match the
210    /// successful bootstrap. A mismatch returns a typed error without
211    /// advancing the durable generation or re-evaluating policy.
212    /// Independently sealed snapshots match when their canonical contents are equal.
213    ///
214    /// # Panics
215    ///
216    /// Panics if a private runtime or encoding invariant is broken, or backing
217    /// memory or a policy callback panics.
218    pub fn bootstrap<P: RuntimeBootstrapPolicy>(
219        &mut self,
220        declarations: &SealedDeclarationSnapshot,
221        pool: &crate::MemoryAllocationPool,
222        policy: &P,
223    ) -> Result<&CommittedAllocations, RuntimeBootstrapError<P::Error>> {
224        let policy_identity = policy.runtime_bootstrap_identity()?;
225        match &self.lifecycle {
226            RuntimeLifecycle::Unbootstrapped => {
227                self.bootstrap_unbootstrapped(declarations, pool, policy, policy_identity)?;
228            }
229            RuntimeLifecycle::Bootstrapped { binding, .. } => {
230                binding.validate(declarations, pool, &policy_identity)?;
231            }
232        }
233        match &self.lifecycle {
234            RuntimeLifecycle::Bootstrapped {
235                committed_allocations,
236                ..
237            } => Ok(committed_allocations),
238            RuntimeLifecycle::Unbootstrapped => {
239                unreachable!("successful bootstrap publishes committed allocations")
240            }
241        }
242    }
243
244    fn validate_pool_custody(
245        &self,
246        ledger: &AllocationLedger,
247        pool: &crate::MemoryAllocationPool,
248    ) -> Result<(), super::MemoryResolutionError> {
249        for id in 0..crate::MEMORY_MANAGER_INVALID_ID {
250            if pool.contains(id)
251                && self.memory_size_pages(id) != 0
252                && !ledger
253                    .records()
254                    .iter()
255                    .any(|record| record.slot().id() == id)
256            {
257                return Err(super::MemoryResolutionError::UnmanagedAllocation { id });
258            }
259        }
260        Ok(())
261    }
262
263    fn bootstrap_unbootstrapped<P: RuntimeBootstrapPolicy>(
264        &mut self,
265        declarations: &SealedDeclarationSnapshot,
266        pool: &crate::MemoryAllocationPool,
267        policy: &P,
268        policy_identity: PolicyIdentity,
269    ) -> Result<(), RuntimeBootstrapError<P::Error>> {
270        let memory = self.memory(MEMORY_MANAGER_LEDGER_ID);
271        let mut record = decode_stable_cell_ledger_record_from_memory(&memory)?;
272        let genesis = AllocationLedger::empty_genesis();
273        let recovered = record.store_mut().recover_or_initialize(&genesis)?;
274        self.validate_pool_custody(recovered.ledger(), pool)?;
275        if memory.size() == 0 {
276            // Empty memory decodes to an uninitialized record. Preserve fresh
277            // cell acquisition before admission without persisting genesis.
278            ensure_ledger_cell_capacity(&memory, &record)?;
279            drop(Cell::new(memory.clone(), StableCellLedgerRecord::default()));
280        }
281        let mut admission = BootstrapAdmission::new(recovered.ledger(), declarations, pool);
282        let preparation = policy.prepare_bootstrap(&mut admission);
283        let historical = admission.complete()?;
284        preparation.map_err(RuntimeBootstrapError::AdmissionPolicy)?;
285        let resolved = declarations.resolve(recovered.ledger(), historical, pool)?;
286        let runtime_policy = RuntimeMemoryManagerPolicy {
287            custom_policy: policy,
288        };
289        let commit = AllocationBootstrap::new(record.store_mut())
290            .validate_against(recovered, resolved, &runtime_policy)
291            .map_err(runtime_bootstrap_error_from_bootstrap)?;
292        ensure_ledger_cell_capacity(&memory, &record)?;
293        drop(Cell::new(memory, record));
294        let committed = commit.confirm_persisted().into_application_allocations();
295        self.lifecycle = RuntimeLifecycle::Bootstrapped {
296            committed_allocations: committed,
297            binding: RuntimeBootstrapBinding {
298                source: declarations.clone(),
299                policy_identity,
300                pool: pool.clone(),
301            },
302        };
303        Ok(())
304    }
305
306    /// Borrow this runtime's committed allocation-open capability.
307    pub const fn committed_allocations(&self) -> Result<&CommittedAllocations, RuntimeOpenError> {
308        match &self.lifecycle {
309            RuntimeLifecycle::Unbootstrapped => Err(RuntimeOpenError::NotBootstrapped),
310            RuntimeLifecycle::Bootstrapped {
311                committed_allocations,
312                ..
313            } => Ok(committed_allocations),
314        }
315    }
316
317    /// Open by durable key using only this runtime's persisted current capability.
318    pub fn open_memory(&self, stable_key: &str) -> Result<RuntimeMemory<M>, RuntimeOpenError> {
319        Ok(self.memory(self.memory_id(stable_key)?))
320    }
321
322    /// Resolve an application key's committed ID without opening memory,
323    /// reading history, or changing the host's policy or bucket configuration.
324    pub fn memory_id(&self, stable_key: &str) -> Result<u8, RuntimeOpenError> {
325        crate::key::validate(stable_key)?;
326        if crate::is_ic_memory_stable_key(stable_key) {
327            return Err(RuntimeOpenError::ReservedStableKey {
328                stable_key: stable_key.to_string(),
329            });
330        }
331        let declaration = crate::capability::declaration_for_key(
332            self.committed_allocations()?.declarations(),
333            stable_key,
334        )
335        .ok_or_else(|| RuntimeOpenError::StableKeyNotCommitted(stable_key.to_string()))?;
336        Ok(declaration.slot().id())
337    }
338
339    fn memory(&self, id: u8) -> RuntimeMemory<M> {
340        RuntimeMemory {
341            memory: self.memory_manager.get(MemoryId::new(id)),
342            growth: Rc::clone(&self.growth),
343        }
344    }
345
346    // Size-only observations need no handle carrying runtime growth authority.
347    fn memory_size_pages(&self, id: u8) -> u64 {
348        self.memory_manager.get(MemoryId::new(id)).size()
349    }
350
351    fn ledger_record_from_memory(&self) -> Result<StableCellLedgerRecord, StableCellLedgerError> {
352        // Decoding only reads; the manager handle retains backing lifetime
353        // without carrying the growth owner needed by writable runtime handles.
354        let memory = self
355            .memory_manager
356            .get(MemoryId::new(MEMORY_MANAGER_LEDGER_ID));
357        decode_stable_cell_ledger_record_from_memory(&memory)
358    }
359}
360
361impl RuntimeBootstrapBinding {
362    fn validate<P>(
363        &self,
364        declarations: &SealedDeclarationSnapshot,
365        pool: &crate::MemoryAllocationPool,
366        policy_identity: &PolicyIdentity,
367    ) -> Result<(), RuntimeBootstrapError<P>> {
368        if &self.source != declarations {
369            return Err(RuntimeBootstrapError::DeclarationSnapshotMismatch);
370        }
371        if &self.pool != pool {
372            return Err(RuntimeBootstrapError::AllocationPoolMismatch);
373        }
374        if &self.policy_identity != policy_identity {
375            return Err(RuntimeBootstrapError::PolicyIdentityMismatch {
376                established: self.policy_identity.clone(),
377                requested: policy_identity.clone(),
378            });
379        }
380        Ok(())
381    }
382}
383
384fn ensure_ledger_cell_capacity<M: Memory, P>(
385    memory: &RuntimeMemory<M>,
386    record: &StableCellLedgerRecord,
387) -> Result<(), RuntimeBootstrapError<P>> {
388    let value_size = record.encoded_size();
389    if value_size > crate::constants::MAX_LEDGER_RECORD_BYTES {
390        return Err(RuntimeBootstrapError::StableCellLedgerWriteTooLarge { value_size });
391    }
392    // The record limit is below u32::MAX, including the eight-byte cell header.
393    let required_bytes = STABLE_CELL_VALUE_OFFSET + value_size as u64;
394    let available_bytes = memory.size().saturating_mul(crate::WASM_PAGE_SIZE_BYTES);
395    if required_bytes <= available_bytes {
396        return Ok(());
397    }
398    let grow_by = (required_bytes - available_bytes).div_ceil(crate::WASM_PAGE_SIZE_BYTES);
399    memory.grow(grow_by)?;
400    Ok(())
401}
402
403const fn check_bucket_size(
404    actual: u16,
405    requested: MemoryManagerConfig,
406) -> Result<(), RuntimeConstructionError> {
407    if actual != requested.bucket_size_pages() {
408        return Err(RuntimeConstructionError::BucketSizeMismatch {
409            persisted: actual,
410            requested: requested.bucket_size_pages(),
411        });
412    }
413    Ok(())
414}
ic_memory/runtime/mod.rs

ic_memory/runtime/
mod.rs
