739 lines
20 KiB
C++
739 lines
20 KiB
C++
#include <kernel/Arch.h>
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#include <kernel/CPUID.h>
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#include <kernel/InterruptController.h>
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#include <kernel/LockGuard.h>
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#include <kernel/Memory/kmalloc.h>
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#include <kernel/Memory/PageTable.h>
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#include <kernel/multiboot2.h>
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extern uint8_t g_kernel_start[];
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extern uint8_t g_kernel_end[];
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extern uint8_t g_kernel_execute_start[];
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extern uint8_t g_kernel_execute_end[];
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extern uint8_t g_userspace_start[];
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extern uint8_t g_userspace_end[];
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namespace Kernel
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{
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static PageTable* s_kernel = nullptr;
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static PageTable* s_current = nullptr;
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static bool s_has_nxe = false;
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static bool s_has_pge = false;
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// PML4 entry for kernel memory
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static paddr_t s_global_pml4e = 0;
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static constexpr inline bool is_canonical(uintptr_t addr)
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{
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constexpr uintptr_t mask = 0xFFFF800000000000;
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addr &= mask;
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return addr == mask || addr == 0;
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}
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static constexpr inline uintptr_t uncanonicalize(uintptr_t addr)
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{
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if (addr & 0x0000800000000000)
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return addr & ~0xFFFF000000000000;
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return addr;
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}
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static constexpr inline uintptr_t canonicalize(uintptr_t addr)
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{
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if (addr & 0x0000800000000000)
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return addr | 0xFFFF000000000000;
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return addr;
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}
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static inline PageTable::flags_t parse_flags(uint64_t entry)
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{
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using Flags = PageTable::Flags;
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PageTable::flags_t result = 0;
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if (s_has_nxe && !(entry & (1ull << 63)))
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result |= Flags::Execute;
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if (entry & Flags::Reserved)
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result |= Flags::Reserved;
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if (entry & Flags::CacheDisable)
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result |= Flags::CacheDisable;
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if (entry & Flags::UserSupervisor)
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result |= Flags::UserSupervisor;
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if (entry & Flags::ReadWrite)
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result |= Flags::ReadWrite;
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if (entry & Flags::Present)
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result |= Flags::Present;
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return result;
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}
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void PageTable::initialize()
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{
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if (CPUID::has_nxe())
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{
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asm volatile(
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"movl $0xC0000080, %ecx;"
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"rdmsr;"
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"orl $0x800, %eax;"
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"wrmsr"
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);
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s_has_nxe = true;
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}
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uint32_t ecx, edx;
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CPUID::get_features(ecx, edx);
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if (edx & CPUID::EDX_PGE)
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{
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asm volatile(
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"movq %cr4, %rax;"
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"orq $0x80, %rax;"
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"movq %rax, %cr4;"
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);
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s_has_pge = true;
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}
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// enable write protect to kernel
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asm volatile(
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"movq %cr0, %rax;"
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"orq $0x10000, %rax;"
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"movq %rax, %cr0;"
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);
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ASSERT(s_kernel == nullptr);
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s_kernel = new PageTable();
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ASSERT(s_kernel);
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s_kernel->initialize_kernel();
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s_kernel->load();
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}
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PageTable& PageTable::kernel()
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{
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ASSERT(s_kernel);
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return *s_kernel;
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}
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PageTable& PageTable::current()
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{
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ASSERT(s_current);
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return *s_current;
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}
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bool PageTable::is_valid_pointer(uintptr_t pointer)
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{
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if (!is_canonical(pointer))
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return false;
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return true;
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}
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static uint64_t* allocate_zeroed_page_aligned_page()
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{
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void* page = kmalloc(PAGE_SIZE, PAGE_SIZE, true);
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ASSERT(page);
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memset(page, 0, PAGE_SIZE);
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return (uint64_t*)page;
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}
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void PageTable::initialize_kernel()
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{
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ASSERT(s_global_pml4e == 0);
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s_global_pml4e = V2P(allocate_zeroed_page_aligned_page());
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m_highest_paging_struct = V2P(allocate_zeroed_page_aligned_page());
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uint64_t* pml4 = (uint64_t*)P2V(m_highest_paging_struct);
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pml4[511] = s_global_pml4e;
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prepare_fast_page();
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// Map (phys_kernel_start -> phys_kernel_end) to (virt_kernel_start -> virt_kernel_end)
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ASSERT((vaddr_t)g_kernel_start % PAGE_SIZE == 0);
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map_range_at(
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V2P(g_kernel_start),
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(vaddr_t)g_kernel_start,
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g_kernel_end - g_kernel_start,
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Flags::ReadWrite | Flags::Present
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);
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// Map executable kernel memory as executable
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map_range_at(
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V2P(g_kernel_execute_start),
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(vaddr_t)g_kernel_execute_start,
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g_kernel_execute_end - g_kernel_execute_start,
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Flags::Execute | Flags::Present
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);
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// Map userspace memory
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map_range_at(
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V2P(g_userspace_start),
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(vaddr_t)g_userspace_start,
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g_userspace_end - g_userspace_start,
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Flags::Execute | Flags::UserSupervisor | Flags::Present
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);
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// Map multiboot memory
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paddr_t multiboot2_data_start = (vaddr_t)g_multiboot2_info & PAGE_ADDR_MASK;
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paddr_t multiboot2_data_end = (vaddr_t)g_multiboot2_info + g_multiboot2_info->total_size;
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size_t multiboot2_needed_pages = BAN::Math::div_round_up<size_t>(multiboot2_data_end - multiboot2_data_start, PAGE_SIZE);
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vaddr_t multiboot2_vaddr = reserve_free_contiguous_pages(multiboot2_needed_pages, KERNEL_OFFSET);
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map_range_at(
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multiboot2_data_start,
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multiboot2_vaddr,
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multiboot2_needed_pages * PAGE_SIZE,
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Flags::ReadWrite | Flags::Present
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);
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g_multiboot2_info = (multiboot2_info_t*)(multiboot2_vaddr + ((vaddr_t)g_multiboot2_info % PAGE_SIZE));
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}
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void PageTable::prepare_fast_page()
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{
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constexpr vaddr_t uc_vaddr = uncanonicalize(fast_page());
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constexpr uint64_t pml4e = (uc_vaddr >> 39) & 0x1FF;
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constexpr uint64_t pdpte = (uc_vaddr >> 30) & 0x1FF;
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constexpr uint64_t pde = (uc_vaddr >> 21) & 0x1FF;
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constexpr uint64_t pte = (uc_vaddr >> 12) & 0x1FF;
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uint64_t* pml4 = (uint64_t*)P2V(m_highest_paging_struct);
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ASSERT(!(pml4[pml4e] & Flags::Present));
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pml4[pml4e] = V2P(allocate_zeroed_page_aligned_page()) | Flags::ReadWrite | Flags::Present;
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uint64_t* pdpt = (uint64_t*)P2V(pml4[pml4e] & PAGE_ADDR_MASK);
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ASSERT(!(pdpt[pdpte] & Flags::Present));
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pdpt[pdpte] = V2P(allocate_zeroed_page_aligned_page()) | Flags::ReadWrite | Flags::Present;
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uint64_t* pd = (uint64_t*)P2V(pdpt[pdpte] & PAGE_ADDR_MASK);
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ASSERT(!(pd[pde] & Flags::Present));
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pd[pde] = V2P(allocate_zeroed_page_aligned_page()) | Flags::ReadWrite | Flags::Present;
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uint64_t* pt = (uint64_t*)P2V(pd[pde] & PAGE_ADDR_MASK);
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ASSERT(!(pt[pte] & Flags::Present));
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pt[pte] = V2P(allocate_zeroed_page_aligned_page());
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}
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void PageTable::map_fast_page(paddr_t paddr)
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{
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ASSERT(s_kernel);
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ASSERT_NEQ(paddr, 0);
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ASSERT(!interrupts_enabled());
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constexpr vaddr_t uc_vaddr = uncanonicalize(fast_page());
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constexpr uint64_t pml4e = (uc_vaddr >> 39) & 0x1FF;
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constexpr uint64_t pdpte = (uc_vaddr >> 30) & 0x1FF;
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constexpr uint64_t pde = (uc_vaddr >> 21) & 0x1FF;
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constexpr uint64_t pte = (uc_vaddr >> 12) & 0x1FF;
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uint64_t* pml4 = (uint64_t*)P2V(s_kernel->m_highest_paging_struct);
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uint64_t* pdpt = (uint64_t*)P2V(pml4[pml4e] & PAGE_ADDR_MASK);
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uint64_t* pd = (uint64_t*)P2V(pdpt[pdpte] & PAGE_ADDR_MASK);
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uint64_t* pt = (uint64_t*)P2V(pd[pde] & PAGE_ADDR_MASK);
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ASSERT(!(pt[pte] & Flags::Present));
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pt[pte] = paddr | Flags::ReadWrite | Flags::Present;
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invalidate(fast_page());
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}
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void PageTable::unmap_fast_page()
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{
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ASSERT(s_kernel);
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ASSERT(!interrupts_enabled());
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constexpr vaddr_t uc_vaddr = uncanonicalize(fast_page());
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constexpr uint64_t pml4e = (uc_vaddr >> 39) & 0x1FF;
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constexpr uint64_t pdpte = (uc_vaddr >> 30) & 0x1FF;
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constexpr uint64_t pde = (uc_vaddr >> 21) & 0x1FF;
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constexpr uint64_t pte = (uc_vaddr >> 12) & 0x1FF;
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uint64_t* pml4 = (uint64_t*)P2V(s_kernel->m_highest_paging_struct);
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uint64_t* pdpt = (uint64_t*)P2V(pml4[pml4e] & PAGE_ADDR_MASK);
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uint64_t* pd = (uint64_t*)P2V(pdpt[pdpte] & PAGE_ADDR_MASK);
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uint64_t* pt = (uint64_t*)P2V(pd[pde] & PAGE_ADDR_MASK);
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ASSERT(pt[pte] & Flags::Present);
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pt[pte] = 0;
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invalidate(fast_page());
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}
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BAN::ErrorOr<PageTable*> PageTable::create_userspace()
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{
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LockGuard _(s_kernel->m_lock);
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PageTable* page_table = new PageTable;
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if (page_table == nullptr)
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return BAN::Error::from_errno(ENOMEM);
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page_table->map_kernel_memory();
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return page_table;
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}
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void PageTable::map_kernel_memory()
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{
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ASSERT(s_kernel);
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ASSERT(s_global_pml4e);
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ASSERT(m_highest_paging_struct == 0);
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m_highest_paging_struct = V2P(allocate_zeroed_page_aligned_page());
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uint64_t* kernel_pml4 = (uint64_t*)P2V(s_kernel->m_highest_paging_struct);
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uint64_t* pml4 = (uint64_t*)P2V(m_highest_paging_struct);
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pml4[511] = kernel_pml4[511];
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}
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PageTable::~PageTable()
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{
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uint64_t* pml4 = (uint64_t*)P2V(m_highest_paging_struct);
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// NOTE: we only loop until 511 since the last one is the kernel memory
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for (uint64_t pml4e = 0; pml4e < 511; pml4e++)
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{
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if (!(pml4[pml4e] & Flags::Present))
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continue;
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uint64_t* pdpt = (uint64_t*)P2V(pml4[pml4e] & PAGE_ADDR_MASK);
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for (uint64_t pdpte = 0; pdpte < 512; pdpte++)
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{
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if (!(pdpt[pdpte] & Flags::Present))
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continue;
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uint64_t* pd = (uint64_t*)P2V(pdpt[pdpte] & PAGE_ADDR_MASK);
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for (uint64_t pde = 0; pde < 512; pde++)
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{
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if (!(pd[pde] & Flags::Present))
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continue;
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kfree((void*)P2V(pd[pde] & PAGE_ADDR_MASK));
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}
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kfree(pd);
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}
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kfree(pdpt);
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}
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kfree(pml4);
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}
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void PageTable::load()
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{
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asm volatile("movq %0, %%cr3" :: "r"(m_highest_paging_struct));
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s_current = this;
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}
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void PageTable::invalidate(vaddr_t vaddr)
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{
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ASSERT(vaddr % PAGE_SIZE == 0);
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asm volatile("invlpg (%0)" :: "r"(vaddr) : "memory");
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}
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void PageTable::unmap_page(vaddr_t vaddr)
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{
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ASSERT(vaddr);
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ASSERT(vaddr != fast_page());
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if (vaddr >= KERNEL_OFFSET)
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ASSERT_GTE(vaddr, (vaddr_t)g_kernel_start);
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if ((vaddr >= KERNEL_OFFSET) != (this == s_kernel))
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Kernel::panic("unmapping {8H}, kernel: {}", vaddr, this == s_kernel);
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ASSERT(is_canonical(vaddr));
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vaddr_t uc_vaddr = uncanonicalize(vaddr);
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ASSERT(vaddr % PAGE_SIZE == 0);
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uint64_t pml4e = (uc_vaddr >> 39) & 0x1FF;
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uint64_t pdpte = (uc_vaddr >> 30) & 0x1FF;
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uint64_t pde = (uc_vaddr >> 21) & 0x1FF;
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uint64_t pte = (uc_vaddr >> 12) & 0x1FF;
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LockGuard _(m_lock);
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if (is_page_free(vaddr))
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{
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dwarnln("unmapping unmapped page {8H}", vaddr);
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return;
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}
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uint64_t* pml4 = (uint64_t*)P2V(m_highest_paging_struct);
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uint64_t* pdpt = (uint64_t*)P2V(pml4[pml4e] & PAGE_ADDR_MASK);
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uint64_t* pd = (uint64_t*)P2V(pdpt[pdpte] & PAGE_ADDR_MASK);
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uint64_t* pt = (uint64_t*)P2V(pd[pde] & PAGE_ADDR_MASK);
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pt[pte] = 0;
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invalidate(vaddr);
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}
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void PageTable::unmap_range(vaddr_t vaddr, size_t size)
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{
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vaddr_t s_page = vaddr / PAGE_SIZE;
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vaddr_t e_page = BAN::Math::div_round_up<vaddr_t>(vaddr + size, PAGE_SIZE);
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LockGuard _(m_lock);
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for (vaddr_t page = s_page; page < e_page; page++)
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unmap_page(page * PAGE_SIZE);
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}
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void PageTable::map_page_at(paddr_t paddr, vaddr_t vaddr, flags_t flags)
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{
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ASSERT(vaddr);
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ASSERT(vaddr != fast_page());
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if (vaddr >= KERNEL_OFFSET)
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ASSERT_GTE(vaddr, (vaddr_t)g_kernel_start);
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if ((vaddr >= KERNEL_OFFSET) != (this == s_kernel))
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Kernel::panic("mapping {8H} to {8H}, kernel: {}", paddr, vaddr, this == s_kernel);
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ASSERT(is_canonical(vaddr));
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vaddr_t uc_vaddr = uncanonicalize(vaddr);
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ASSERT(paddr % PAGE_SIZE == 0);
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ASSERT(vaddr % PAGE_SIZE == 0);
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ASSERT(flags & Flags::Used);
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uint64_t pml4e = (uc_vaddr >> 39) & 0x1FF;
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uint64_t pdpte = (uc_vaddr >> 30) & 0x1FF;
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uint64_t pde = (uc_vaddr >> 21) & 0x1FF;
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uint64_t pte = (uc_vaddr >> 12) & 0x1FF;
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uint64_t extra_flags = 0;
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if (s_has_pge && pml4e == 511) // Map kernel memory as global
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extra_flags |= 1ull << 8;
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if (s_has_nxe && !(flags & Flags::Execute))
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extra_flags |= 1ull << 63;
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if (flags & Flags::Reserved)
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extra_flags |= Flags::Reserved;
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if (flags & Flags::CacheDisable)
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extra_flags |= Flags::CacheDisable;
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// NOTE: we add present here, since it has to be available in higher level structures
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flags_t uwr_flags = (flags & (Flags::UserSupervisor | Flags::ReadWrite)) | Flags::Present;
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LockGuard _(m_lock);
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uint64_t* pml4 = (uint64_t*)P2V(m_highest_paging_struct);
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if ((pml4[pml4e] & uwr_flags) != uwr_flags)
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{
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if (!(pml4[pml4e] & Flags::Present))
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pml4[pml4e] = V2P(allocate_zeroed_page_aligned_page());
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pml4[pml4e] |= uwr_flags;
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}
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uint64_t* pdpt = (uint64_t*)P2V(pml4[pml4e] & PAGE_ADDR_MASK);
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if ((pdpt[pdpte] & uwr_flags) != uwr_flags)
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{
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if (!(pdpt[pdpte] & Flags::Present))
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pdpt[pdpte] = V2P(allocate_zeroed_page_aligned_page());
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pdpt[pdpte] |= uwr_flags;
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}
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uint64_t* pd = (uint64_t*)P2V(pdpt[pdpte] & PAGE_ADDR_MASK);
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if ((pd[pde] & uwr_flags) != uwr_flags)
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{
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if (!(pd[pde] & Flags::Present))
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pd[pde] = V2P(allocate_zeroed_page_aligned_page());
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pd[pde] |= uwr_flags;
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}
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if (!(flags & Flags::Present))
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uwr_flags &= ~Flags::Present;
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uint64_t* pt = (uint64_t*)P2V(pd[pde] & PAGE_ADDR_MASK);
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pt[pte] = paddr | uwr_flags | extra_flags;
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invalidate(vaddr);
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}
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void PageTable::map_range_at(paddr_t paddr, vaddr_t vaddr, size_t size, flags_t flags)
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{
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ASSERT(is_canonical(vaddr));
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ASSERT(vaddr);
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ASSERT(paddr % PAGE_SIZE == 0);
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ASSERT(vaddr % PAGE_SIZE == 0);
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size_t page_count = range_page_count(vaddr, size);
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LockGuard _(m_lock);
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for (size_t page = 0; page < page_count; page++)
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map_page_at(paddr + page * PAGE_SIZE, vaddr + page * PAGE_SIZE, flags);
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}
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uint64_t PageTable::get_page_data(vaddr_t vaddr) const
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{
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ASSERT(is_canonical(vaddr));
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vaddr_t uc_vaddr = uncanonicalize(vaddr);
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ASSERT(vaddr % PAGE_SIZE == 0);
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uint64_t pml4e = (uc_vaddr >> 39) & 0x1FF;
|
|
uint64_t pdpte = (uc_vaddr >> 30) & 0x1FF;
|
|
uint64_t pde = (uc_vaddr >> 21) & 0x1FF;
|
|
uint64_t pte = (uc_vaddr >> 12) & 0x1FF;
|
|
|
|
LockGuard _(m_lock);
|
|
|
|
uint64_t* pml4 = (uint64_t*)P2V(m_highest_paging_struct);
|
|
if (!(pml4[pml4e] & Flags::Present))
|
|
return 0;
|
|
|
|
uint64_t* pdpt = (uint64_t*)P2V(pml4[pml4e] & PAGE_ADDR_MASK);
|
|
if (!(pdpt[pdpte] & Flags::Present))
|
|
return 0;
|
|
|
|
uint64_t* pd = (uint64_t*)P2V(pdpt[pdpte] & PAGE_ADDR_MASK);
|
|
if (!(pd[pde] & Flags::Present))
|
|
return 0;
|
|
|
|
uint64_t* pt = (uint64_t*)P2V(pd[pde] & PAGE_ADDR_MASK);
|
|
if (!(pt[pte] & Flags::Used))
|
|
return 0;
|
|
|
|
return pt[pte];
|
|
}
|
|
|
|
PageTable::flags_t PageTable::get_page_flags(vaddr_t addr) const
|
|
{
|
|
return parse_flags(get_page_data(addr));
|
|
}
|
|
|
|
paddr_t PageTable::physical_address_of(vaddr_t addr) const
|
|
{
|
|
uint64_t page_data = get_page_data(addr);
|
|
return (page_data & PAGE_ADDR_MASK) & ~(1ull << 63);
|
|
}
|
|
|
|
bool PageTable::reserve_page(vaddr_t vaddr, bool only_free)
|
|
{
|
|
LockGuard _(m_lock);
|
|
ASSERT(vaddr % PAGE_SIZE == 0);
|
|
if (only_free && !is_page_free(vaddr))
|
|
return false;
|
|
map_page_at(0, vaddr, Flags::Reserved);
|
|
return true;
|
|
}
|
|
|
|
bool PageTable::reserve_range(vaddr_t vaddr, size_t bytes, bool only_free)
|
|
{
|
|
if (size_t rem = bytes % PAGE_SIZE)
|
|
bytes += PAGE_SIZE - rem;
|
|
ASSERT(vaddr % PAGE_SIZE == 0);
|
|
|
|
LockGuard _(m_lock);
|
|
if (only_free && !is_range_free(vaddr, bytes))
|
|
return false;
|
|
for (size_t offset = 0; offset < bytes; offset += PAGE_SIZE)
|
|
reserve_page(vaddr + offset);
|
|
return true;
|
|
}
|
|
|
|
vaddr_t PageTable::reserve_free_page(vaddr_t first_address, vaddr_t last_address)
|
|
{
|
|
if (first_address >= KERNEL_OFFSET && first_address < (vaddr_t)g_kernel_end)
|
|
first_address = (vaddr_t)g_kernel_end;
|
|
if (size_t rem = first_address % PAGE_SIZE)
|
|
first_address += PAGE_SIZE - rem;
|
|
if (size_t rem = last_address % PAGE_SIZE)
|
|
last_address -= rem;
|
|
|
|
ASSERT(is_canonical(first_address));
|
|
ASSERT(is_canonical(last_address));
|
|
const vaddr_t uc_vaddr_start = uncanonicalize(first_address);
|
|
const vaddr_t uc_vaddr_end = uncanonicalize(last_address);
|
|
|
|
uint16_t pml4e = (uc_vaddr_start >> 39) & 0x1FF;
|
|
uint16_t pdpte = (uc_vaddr_start >> 30) & 0x1FF;
|
|
uint16_t pde = (uc_vaddr_start >> 21) & 0x1FF;
|
|
uint16_t pte = (uc_vaddr_start >> 12) & 0x1FF;
|
|
|
|
const uint16_t e_pml4e = (uc_vaddr_end >> 39) & 0x1FF;
|
|
const uint16_t e_pdpte = (uc_vaddr_end >> 30) & 0x1FF;
|
|
const uint16_t e_pde = (uc_vaddr_end >> 21) & 0x1FF;
|
|
const uint16_t e_pte = (uc_vaddr_end >> 12) & 0x1FF;
|
|
|
|
LockGuard _(m_lock);
|
|
|
|
// Try to find free page that can be mapped without
|
|
// allocations (page table with unused entries)
|
|
uint64_t* pml4 = (uint64_t*)P2V(m_highest_paging_struct);
|
|
for (; pml4e < 512; pml4e++)
|
|
{
|
|
if (pml4e > e_pml4e)
|
|
break;
|
|
if (!(pml4[pml4e] & Flags::Present))
|
|
continue;
|
|
uint64_t* pdpt = (uint64_t*)P2V(pml4[pml4e] & PAGE_ADDR_MASK);
|
|
for (; pdpte < 512; pdpte++)
|
|
{
|
|
if (pml4e == e_pml4e && pdpte > e_pdpte)
|
|
break;
|
|
if (!(pdpt[pdpte] & Flags::Present))
|
|
continue;
|
|
uint64_t* pd = (uint64_t*)P2V(pdpt[pdpte] & PAGE_ADDR_MASK);
|
|
for (; pde < 512; pde++)
|
|
{
|
|
if (pml4e == e_pml4e && pdpte == e_pdpte && pde > e_pde)
|
|
break;
|
|
if (!(pd[pde] & Flags::Present))
|
|
continue;
|
|
uint64_t* pt = (uint64_t*)P2V(pd[pde] & PAGE_ADDR_MASK);
|
|
for (; pte < 512; pte++)
|
|
{
|
|
if (pml4e == e_pml4e && pdpte == e_pdpte && pde == e_pde && pte >= e_pte)
|
|
break;
|
|
if (!(pt[pte] & Flags::Used))
|
|
{
|
|
vaddr_t vaddr = 0;
|
|
vaddr |= (uint64_t)pml4e << 39;
|
|
vaddr |= (uint64_t)pdpte << 30;
|
|
vaddr |= (uint64_t)pde << 21;
|
|
vaddr |= (uint64_t)pte << 12;
|
|
vaddr = canonicalize(vaddr);
|
|
ASSERT(reserve_page(vaddr));
|
|
return vaddr;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// Find any free page
|
|
vaddr_t uc_vaddr = uc_vaddr_start;
|
|
while (uc_vaddr < uc_vaddr_end)
|
|
{
|
|
if (vaddr_t vaddr = canonicalize(uc_vaddr); is_page_free(vaddr))
|
|
{
|
|
ASSERT(reserve_page(vaddr));
|
|
return vaddr;
|
|
}
|
|
uc_vaddr += PAGE_SIZE;
|
|
}
|
|
|
|
ASSERT_NOT_REACHED();
|
|
}
|
|
|
|
vaddr_t PageTable::reserve_free_contiguous_pages(size_t page_count, vaddr_t first_address, vaddr_t last_address)
|
|
{
|
|
if (first_address >= KERNEL_OFFSET && first_address < (vaddr_t)g_kernel_start)
|
|
first_address = (vaddr_t)g_kernel_start;
|
|
if (size_t rem = first_address % PAGE_SIZE)
|
|
first_address += PAGE_SIZE - rem;
|
|
if (size_t rem = last_address % PAGE_SIZE)
|
|
last_address -= rem;
|
|
|
|
ASSERT(is_canonical(first_address));
|
|
ASSERT(is_canonical(last_address));
|
|
|
|
LockGuard _(m_lock);
|
|
|
|
for (vaddr_t vaddr = first_address; vaddr < last_address;)
|
|
{
|
|
bool valid { true };
|
|
for (size_t page = 0; page < page_count; page++)
|
|
{
|
|
if (!is_canonical(vaddr + page * PAGE_SIZE))
|
|
{
|
|
vaddr = canonicalize(uncanonicalize(vaddr) + page * PAGE_SIZE);
|
|
valid = false;
|
|
break;
|
|
}
|
|
if (!is_page_free(vaddr + page * PAGE_SIZE))
|
|
{
|
|
vaddr += (page + 1) * PAGE_SIZE;
|
|
valid = false;
|
|
break;
|
|
}
|
|
}
|
|
if (valid)
|
|
{
|
|
ASSERT(reserve_range(vaddr, page_count * PAGE_SIZE));
|
|
return vaddr;
|
|
}
|
|
}
|
|
|
|
ASSERT_NOT_REACHED();
|
|
}
|
|
|
|
bool PageTable::is_page_free(vaddr_t page) const
|
|
{
|
|
ASSERT(page % PAGE_SIZE == 0);
|
|
return !(get_page_flags(page) & Flags::Used);
|
|
}
|
|
|
|
bool PageTable::is_range_free(vaddr_t vaddr, size_t size) const
|
|
{
|
|
vaddr_t s_page = vaddr / PAGE_SIZE;
|
|
vaddr_t e_page = BAN::Math::div_round_up<vaddr_t>(vaddr + size, PAGE_SIZE);
|
|
|
|
LockGuard _(m_lock);
|
|
for (vaddr_t page = s_page; page < e_page; page++)
|
|
if (!is_page_free(page * PAGE_SIZE))
|
|
return false;
|
|
return true;
|
|
}
|
|
|
|
static void dump_range(vaddr_t start, vaddr_t end, PageTable::flags_t flags)
|
|
{
|
|
if (start == 0)
|
|
return;
|
|
dprintln("{}-{}: {}{}{}{}",
|
|
(void*)canonicalize(start),
|
|
(void*)canonicalize(end - 1),
|
|
flags & PageTable::Flags::Execute ? 'x' : '-',
|
|
flags & PageTable::Flags::UserSupervisor ? 'u' : '-',
|
|
flags & PageTable::Flags::ReadWrite ? 'w' : '-',
|
|
flags & PageTable::Flags::Present ? 'r' : '-'
|
|
);
|
|
}
|
|
|
|
void PageTable::debug_dump()
|
|
{
|
|
LockGuard _(m_lock);
|
|
|
|
flags_t flags = 0;
|
|
vaddr_t start = 0;
|
|
|
|
uint64_t* pml4 = (uint64_t*)P2V(m_highest_paging_struct);
|
|
for (uint64_t pml4e = 0; pml4e < 512; pml4e++)
|
|
{
|
|
if (!(pml4[pml4e] & Flags::Present))
|
|
{
|
|
dump_range(start, (pml4e << 39), flags);
|
|
start = 0;
|
|
continue;
|
|
}
|
|
uint64_t* pdpt = (uint64_t*)P2V(pml4[pml4e] & PAGE_ADDR_MASK);
|
|
for (uint64_t pdpte = 0; pdpte < 512; pdpte++)
|
|
{
|
|
if (!(pdpt[pdpte] & Flags::Present))
|
|
{
|
|
dump_range(start, (pml4e << 39) | (pdpte << 30), flags);
|
|
start = 0;
|
|
continue;
|
|
}
|
|
uint64_t* pd = (uint64_t*)P2V(pdpt[pdpte] & PAGE_ADDR_MASK);
|
|
for (uint64_t pde = 0; pde < 512; pde++)
|
|
{
|
|
if (!(pd[pde] & Flags::Present))
|
|
{
|
|
dump_range(start, (pml4e << 39) | (pdpte << 30) | (pde << 21), flags);
|
|
start = 0;
|
|
continue;
|
|
}
|
|
uint64_t* pt = (uint64_t*)P2V(pd[pde] & PAGE_ADDR_MASK);
|
|
for (uint64_t pte = 0; pte < 512; pte++)
|
|
{
|
|
if (parse_flags(pt[pte]) != flags)
|
|
{
|
|
dump_range(start, (pml4e << 39) | (pdpte << 30) | (pde << 21) | (pte << 12), flags);
|
|
start = 0;
|
|
}
|
|
|
|
if (!(pt[pte] & Flags::Used))
|
|
continue;
|
|
|
|
if (start == 0)
|
|
{
|
|
flags = parse_flags(pt[pte]);
|
|
start = (pml4e << 39) | (pdpte << 30) | (pde << 21) | (pte << 12);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
}
|