diff options
Diffstat (limited to 'Kernel/MemoryManager.cpp')
| -rw-r--r-- | Kernel/MemoryManager.cpp | 32 |
1 files changed, 31 insertions, 1 deletions
diff --git a/Kernel/MemoryManager.cpp b/Kernel/MemoryManager.cpp index e3416bcb22..a81b6767c3 100644 --- a/Kernel/MemoryManager.cpp +++ b/Kernel/MemoryManager.cpp @@ -224,6 +224,24 @@ Region* MemoryManager::region_from_laddr(Process& process, LinearAddress laddr) return nullptr; } +bool MemoryManager::zero_page(PageDirectory& page_directory, Region& region, unsigned page_index_in_region) +{ + ASSERT_INTERRUPTS_DISABLED(); + auto& vmo = region.vmo(); + auto physical_page = allocate_physical_page(); + byte* dest_ptr = quickmap_page(*physical_page); + memset(dest_ptr, 0, PAGE_SIZE); +#ifdef PAGE_FAULT_DEBUG + dbgprintf(" >> ZERO P%x\n", physical_page->paddr().get()); +#endif + unquickmap_page(); + region.cow_map.set(page_index_in_region, false); + vmo.physical_pages()[page_index_in_region] = move(physical_page); + unquickmap_page(); + remap_region_page(&page_directory, region, page_index_in_region, true); + return true; +} + bool MemoryManager::copy_on_write(Process& process, Region& region, unsigned page_index_in_region) { ASSERT_INTERRUPTS_DISABLED(); @@ -325,7 +343,9 @@ PageFaultResponse MemoryManager::handle_page_fault(const PageFault& fault) page_in_from_vnode(*current->m_page_directory, *region, page_index_in_region); return PageFaultResponse::Continue; } else { - kprintf("NP(error) fault in Region{%p}[%u]\n", region, page_index_in_region); + dbgprintf("NP(zero) fault in Region{%p}[%u]\n", region, page_index_in_region); + zero_page(*current->m_page_directory, *region, page_index_in_region); + return PageFaultResponse::Continue; } } else if (fault.is_protection_violation()) { if (region->cow_map.get(page_index_in_region)) { @@ -761,3 +781,13 @@ inline bool PageDirectory::is_active() const { return ¤t->page_directory() == this; } + +size_t Region::committed() const +{ + size_t bytes = 0; + for (size_t i = 0; i < page_count(); ++i) { + if (m_vmo->physical_pages()[first_page_index() + i]) + bytes += PAGE_SIZE; + } + return bytes; +} |