diff options
Diffstat (limited to 'src/common/page_table.cpp')
-rw-r--r-- | src/common/page_table.cpp | 58 |
1 files changed, 56 insertions, 2 deletions
diff --git a/src/common/page_table.cpp b/src/common/page_table.cpp index 9fffd816f..75897eeae 100644 --- a/src/common/page_table.cpp +++ b/src/common/page_table.cpp @@ -10,11 +10,65 @@ PageTable::PageTable() = default; PageTable::~PageTable() noexcept = default; -void PageTable::Resize(size_t address_space_width_in_bits, size_t page_size_in_bits) { - const size_t num_page_table_entries{1ULL << (address_space_width_in_bits - page_size_in_bits)}; +bool PageTable::BeginTraversal(TraversalEntry* out_entry, TraversalContext* out_context, + u64 address) const { + // Setup invalid defaults. + out_entry->phys_addr = 0; + out_entry->block_size = page_size; + out_context->next_page = 0; + + // Validate that we can read the actual entry. + const auto page = address / page_size; + if (page >= backing_addr.size()) { + return false; + } + + // Validate that the entry is mapped. + const auto phys_addr = backing_addr[page]; + if (phys_addr == 0) { + return false; + } + + // Populate the results. + out_entry->phys_addr = phys_addr + address; + out_context->next_page = page + 1; + out_context->next_offset = address + page_size; + + return true; +} + +bool PageTable::ContinueTraversal(TraversalEntry* out_entry, TraversalContext* context) const { + // Setup invalid defaults. + out_entry->phys_addr = 0; + out_entry->block_size = page_size; + + // Validate that we can read the actual entry. + const auto page = context->next_page; + if (page >= backing_addr.size()) { + return false; + } + + // Validate that the entry is mapped. + const auto phys_addr = backing_addr[page]; + if (phys_addr == 0) { + return false; + } + + // Populate the results. + out_entry->phys_addr = phys_addr + context->next_offset; + context->next_page = page + 1; + context->next_offset += page_size; + + return true; +} + +void PageTable::Resize(std::size_t address_space_width_in_bits, std::size_t page_size_in_bits) { + const std::size_t num_page_table_entries{1ULL + << (address_space_width_in_bits - page_size_in_bits)}; pointers.resize(num_page_table_entries); backing_addr.resize(num_page_table_entries); current_address_space_width_in_bits = address_space_width_in_bits; + page_size = 1ULL << page_size_in_bits; } } // namespace Common |