+++ /dev/null
-#include <arch/x86/boot/multiboot.h>
-#include <arch/x86/idt.h>
-#include <lunaix/mm/page.h>
-#include <lunaix/constants.h>
-
-#define PT_ADDR(ptd, pt_index) ((ptd_t*)ptd + (pt_index + 1) * 1024)
-#define SET_PDE(ptd, pde_index, pde) *((ptd_t*)ptd + pde_index) = pde;
-#define SET_PTE(ptd, pt_index, pte_index, pte) *(PT_ADDR(ptd, pt_index) + pte_index) = pte;
-#define sym_val(sym) (uintptr_t)(&sym)
-
-#define KERNEL_PAGE_COUNT ((sym_val(__kernel_end) - sym_val(__kernel_start) + 0x1000 - 1) >> 12);
-#define HHK_PAGE_COUNT ((sym_val(__init_hhk_end) - 0x100000 + 0x1000 - 1) >> 12)
-
-// use table #1
-#define PG_TABLE_IDENTITY 0
-
-// use table #2-4
-// hence the max size of kernel is 8MiB
-#define PG_TABLE_KERNEL 1
-
-// use table #5
-#define PG_TABLE_STACK 4
-
-// Provided by linker (see linker.ld)
-extern uint8_t __kernel_start;
-extern uint8_t __kernel_end;
-extern uint8_t __init_hhk_end;
-extern uint8_t _k_stack;
-
-void
-_init_page(ptd_t* ptd) {
- SET_PDE(ptd, 0, PDE(PG_PRESENT, ptd + PG_MAX_ENTRIES))
-
- // 对低1MiB空间进行对等映射（Identity mapping），也包括了我们的VGA，方便内核操作。
- for (uint32_t i = 0; i < 256; i++)
- {
- SET_PTE(ptd, PG_TABLE_IDENTITY, i, PTE(PG_PREM_RW, (i << 12)))
- }
-
- // 对等映射我们的hhk_init，这样一来，当分页与地址转换开启后，我们依然能够照常执行最终的 jmp 指令来跳转至
- // 内核的入口点
- for (uint32_t i = 0; i < HHK_PAGE_COUNT; i++)
- {
- SET_PTE(ptd, PG_TABLE_IDENTITY, 256 + i, PTE(PG_PREM_RW, 0x100000 + (i << 12)))
- }
-
- // --- 将内核重映射至高半区 ---
-
- // 这里是一些计算，主要是计算应当映射进的 页目录 与 页表 的条目索引（Entry Index）
- uint32_t kernel_pde_index = PD_INDEX(sym_val(__kernel_start));
- uint32_t kernel_pte_index = PT_INDEX(sym_val(__kernel_start));
- uint32_t kernel_pg_counts = KERNEL_PAGE_COUNT;
-
- // 将内核所需要的页表注册进页目录
- // 当然，就现在而言，我们的内核只占用不到50个页（每个页表包含1024个页）
- // 这里分配了3个页表（12MiB），未雨绸缪。
- for (uint32_t i = 0; i < PG_TABLE_STACK - PG_TABLE_KERNEL; i++)
- {
- SET_PDE(
- ptd,
- kernel_pde_index + i,
- PDE(PG_PREM_RW, PT_ADDR(ptd, PG_TABLE_KERNEL + i))
- )
- }
-
- // 首先，检查内核的大小是否可以fit进我们这几个表（12MiB）
- if (kernel_pg_counts > (PG_TABLE_STACK - PG_TABLE_KERNEL) * 1024) {
- // ERROR: require more pages
- // here should do something else other than head into blocking
- while (1);
- }
-
- // 计算内核.text段的物理地址
- uintptr_t kernel_pm = V2P(&__kernel_start);
-
- // 重映射内核至高半区地址（>=0xC0000000）
- for (uint32_t i = 0; i < kernel_pg_counts; i++)
- {
- SET_PTE(
- ptd,
- PG_TABLE_KERNEL,
- kernel_pte_index + i,
- PTE(PG_PREM_RW, kernel_pm + (i << 12))
- )
- }
-
- // 最后一个entry用于循环映射
- SET_PDE(
- ptd,
- 1023,
- PDE(T_SELF_REF_PERM, ptd)
- );
-}
-
-uint32_t __save_subset(uint8_t* destination, uint8_t* base, unsigned int size) {
- unsigned int i = 0;
- for (; i < size; i++)
- {
- *(destination + i) = *(base + i);
- }
- return i;
-}
-
-void
-_save_multiboot_info(multiboot_info_t* info, uint8_t* destination) {
- uint32_t current = 0;
- uint8_t* info_b = (uint8_t*) info;
- for (; current < sizeof(multiboot_info_t); current++)
- {
- *(destination + current) = *(info_b + current);
- }
-
- ((multiboot_info_t*) destination)->mmap_addr = (uintptr_t)destination + current;
- current += __save_subset(destination + current, (uint8_t*)info->mmap_addr, info->mmap_length);
-
- if (present(info->flags, MULTIBOOT_INFO_DRIVE_INFO)) {
- ((multiboot_info_t*) destination)->drives_addr = (uintptr_t)destination + current;
- current += __save_subset(destination + current, (uint8_t*)info->drives_addr, info->drives_length);
- }
-}
-
-void
-_hhk_init(ptd_t* ptd, uint32_t kpg_size) {
-
- // 初始化 kpg 全为0
- // P.s. 真没想到GRUB会在这里留下一堆垃圾！ 老子的页表全乱套了！
- uint8_t* kpg = (uint8_t*) ptd;
- for (uint32_t i = 0; i < kpg_size; i++)
- {
- *(kpg + i) = 0;
- }
-
- _init_page(ptd);
-}
\ No newline at end of file
git://scm.lunaixsky.com / lunaix-os.git / blobdiff