+++ /dev/null
-#include <arch/x86/boot/multiboot.h>
-#include <arch/x86/idt.h>
-#include <lunaix/common.h>
-#include <lunaix/mm/page.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) (ptr_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 #2-8
-// hence the max size of kernel is 8MiB
-#define PG_TABLE_KERNEL 1
-
-// use table #9
-#define PG_TABLE_STACK 8
-
-// Provided by linker (see linker.ld)
-extern u8_t __kernel_start;
-extern u8_t __kernel_end;
-extern u8_t __ktext_start;
-extern u8_t __ktext_end;
-
-extern u8_t __init_hhk_end;
-extern u8_t _k_stack;
-
-void
-_init_page(x86_page_table* ptd)
-{
- ptd->entry[0] = NEW_L1_ENTRY(PG_PREM_RW, (ptd_t*)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。
- x86_page_table* id_pt =
- (x86_page_table*)GET_PG_ADDR(ptd->entry[PG_TABLE_IDENTITY]);
-
- for (u32_t i = 0; i < 256; i++) {
- id_pt->entry[i] = NEW_L2_ENTRY(PG_PREM_RW, (i << PG_SIZE_BITS));
- }
-
- // 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 (u32_t i = 0; i < HHK_PAGE_COUNT; i++) {
- id_pt->entry[256 + i] =
- NEW_L2_ENTRY(PG_PREM_RW, 0x100000 + (i << PG_SIZE_BITS));
- }
-
- // --- 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)
- u32_t kernel_pde_index = L1_INDEX(sym_val(__kernel_start));
- u32_t kernel_pte_index = L2_INDEX(sym_val(__kernel_start));
- u32_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 (u32_t i = 0; i < PG_TABLE_STACK - PG_TABLE_KERNEL; i++) {
- ptd->entry[kernel_pde_index + i] =
- NEW_L1_ENTRY(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) * PG_MAX_ENTRIES) {
- // ERROR: require more pages
- // here should do something else other than head into blocking
- asm("ud2");
- }
-
- // 计算内核.text段的物理地址
- ptr_t kernel_pm = V2P(&__kernel_start);
- ptr_t ktext_start = V2P(&__ktext_start);
- ptr_t ktext_end = V2P(&ktext_end);
-
- // 重映射内核至高半区地址(>=0xC0000000)
- for (u32_t i = 0; i < kernel_pg_counts; i++) {
- ptr_t paddr = kernel_pm + (i << PG_SIZE_BITS);
- u32_t flags = PG_PREM_RW;
-
- if (paddr >= ktext_start && paddr <= ktext_end) {
- flags = PG_PREM_R;
- }
-
- SET_PTE(ptd,
- PG_TABLE_KERNEL,
- kernel_pte_index + i,
- NEW_L2_ENTRY(flags, paddr))
- }
-
- // 最后一个entry用于循环映射
- ptd->entry[PG_MAX_ENTRIES - 1] = NEW_L1_ENTRY(T_SELF_REF_PERM, ptd);
-}
-
-u32_t
-__save_subset(u8_t* destination, u8_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, u8_t* destination)
-{
- u32_t current = 0;
- u8_t* info_b = (u8_t*)info;
- for (; current < sizeof(multiboot_info_t); current++) {
- *(destination + current) = *(info_b + current);
- }
-
- ((multiboot_info_t*)destination)->mmap_addr = (ptr_t)destination + current;
- current += __save_subset(
- destination + current, (u8_t*)info->mmap_addr, info->mmap_length);
-
- if (present(info->flags, MULTIBOOT_INFO_DRIVE_INFO)) {
- ((multiboot_info_t*)destination)->drives_addr =
- (ptr_t)destination + current;
- current += __save_subset(
- destination + current, (u8_t*)info->drives_addr, info->drives_length);
- }
-}
-
-void
-_hhk_init(x86_page_table* ptd, u32_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!
- u8_t* kpg = (u8_t*)ptd;
- for (u32_t i = 0; i < kpg_size; i++) {
- *(kpg + i) = 0;
- }
-
- _init_page(ptd);
-}
\ No newline at end of file