| 358 | }; |
| 359 | |
| 360 | void walk_xarray(const Engine& eng, const Offsets& o, |
| 361 | VAddr entry, u64 base_index, |
| 362 | std::vector<CachedPage>& out, int depth, std::size_t& budget) |
| 363 | { |
| 364 | if (entry == 0 || depth > 16) return; |
| 365 | // Total-node budget: a depth cap alone doesn't stop a CRAFTED xarray whose |
| 366 | // node slots form a cycle / DAG — with 64-way fanout that re-visits a few |
| 367 | // nodes ~64^depth times (effective hang). The budget bounds total visits. |
| 368 | if (budget == 0) return; |
| 369 | --budget; |
| 370 | if (xa_is_value(entry)) return; // not a pointer entry |
| 371 | |
| 372 | if (!xa_is_internal(entry)) { |
| 373 | // Leaf — folio*. |
| 374 | // For leaves at the root of a small tree, base_index is the slot |
| 375 | // index from the parent. Caller does base_index assembly. |
| 376 | out.push_back({ base_index, entry }); |
| 377 | return; |
| 378 | } |
| 379 | |
| 380 | VAddr node_va = xa_to_node(entry); |
| 381 | u8 shift = 0; |
| 382 | if (!kva_read_pod(eng, node_va + o.xn_shift, shift)) return; |
| 383 | |
| 384 | constexpr u64 kSlots = 64; |
| 385 | std::vector<VAddr> slots(kSlots, 0); |
| 386 | if (!kva_read(eng, node_va + o.xn_slots, slots.data(), |
| 387 | kSlots * sizeof(VAddr))) return; |
| 388 | |
| 389 | for (u64 i = 0; i < kSlots; ++i) { |
| 390 | if (slots[i] == 0) continue; |
| 391 | u64 child_base = base_index | (i << shift); |
| 392 | walk_xarray(eng, o, slots[i], child_base, out, depth + 1, budget); |
| 393 | } |
| 394 | } |
| 395 | |
| 396 | std::vector<CachedPage> |
| 397 | collect_cached_pages(const Engine& eng, const Offsets& o, VAddr inode_va) |
no test coverage detected