| /* |
| * prepare to run common code |
| * |
| * Copyright (C) 2000 Andrea Arcangeli <andrea@suse.de> SuSE |
| */ |
| |
| #include <linux/init.h> |
| #include <linux/linkage.h> |
| #include <linux/types.h> |
| #include <linux/kernel.h> |
| #include <linux/string.h> |
| #include <linux/percpu.h> |
| #include <linux/start_kernel.h> |
| #include <linux/io.h> |
| #include <linux/memblock.h> |
| |
| #include <asm/processor.h> |
| #include <asm/proto.h> |
| #include <asm/smp.h> |
| #include <asm/setup.h> |
| #include <asm/desc.h> |
| #include <asm/pgtable.h> |
| #include <asm/tlbflush.h> |
| #include <asm/sections.h> |
| #include <asm/kdebug.h> |
| #include <asm/e820.h> |
| #include <asm/bios_ebda.h> |
| #include <asm/bootparam_utils.h> |
| #include <asm/microcode.h> |
| #include <asm/kasan.h> |
| |
| /* |
| * Manage page tables very early on. |
| */ |
| extern pgd_t early_level4_pgt[PTRS_PER_PGD]; |
| extern pmd_t early_dynamic_pgts[EARLY_DYNAMIC_PAGE_TABLES][PTRS_PER_PMD]; |
| static unsigned int __initdata next_early_pgt = 2; |
| pmdval_t early_pmd_flags = __PAGE_KERNEL_LARGE & ~(_PAGE_GLOBAL | _PAGE_NX); |
| |
| /* Wipe all early page tables except for the kernel symbol map */ |
| static void __init reset_early_page_tables(void) |
| { |
| unsigned long i; |
| |
| for (i = 0; i < PTRS_PER_PGD-1; i++) |
| early_level4_pgt[i].pgd = 0; |
| |
| next_early_pgt = 0; |
| |
| write_cr3(__pa_nodebug(early_level4_pgt)); |
| } |
| |
| /* Create a new PMD entry */ |
| int __init early_make_pgtable(unsigned long address) |
| { |
| unsigned long physaddr = address - __PAGE_OFFSET; |
| unsigned long i; |
| pgdval_t pgd, *pgd_p; |
| pudval_t pud, *pud_p; |
| pmdval_t pmd, *pmd_p; |
| |
| /* Invalid address or early pgt is done ? */ |
| if (physaddr >= MAXMEM || read_cr3() != __pa_nodebug(early_level4_pgt)) |
| return -1; |
| |
| again: |
| pgd_p = &early_level4_pgt[pgd_index(address)].pgd; |
| pgd = *pgd_p; |
| |
| /* |
| * The use of __START_KERNEL_map rather than __PAGE_OFFSET here is |
| * critical -- __PAGE_OFFSET would point us back into the dynamic |
| * range and we might end up looping forever... |
| */ |
| if (pgd) |
| pud_p = (pudval_t *)((pgd & PTE_PFN_MASK) + __START_KERNEL_map - phys_base); |
| else { |
| if (next_early_pgt >= EARLY_DYNAMIC_PAGE_TABLES) { |
| reset_early_page_tables(); |
| goto again; |
| } |
| |
| pud_p = (pudval_t *)early_dynamic_pgts[next_early_pgt++]; |
| for (i = 0; i < PTRS_PER_PUD; i++) |
| pud_p[i] = 0; |
| *pgd_p = (pgdval_t)pud_p - __START_KERNEL_map + phys_base + _KERNPG_TABLE; |
| } |
| pud_p += pud_index(address); |
| pud = *pud_p; |
| |
| if (pud) |
| pmd_p = (pmdval_t *)((pud & PTE_PFN_MASK) + __START_KERNEL_map - phys_base); |
| else { |
| if (next_early_pgt >= EARLY_DYNAMIC_PAGE_TABLES) { |
| reset_early_page_tables(); |
| goto again; |
| } |
| |
| pmd_p = (pmdval_t *)early_dynamic_pgts[next_early_pgt++]; |
| for (i = 0; i < PTRS_PER_PMD; i++) |
| pmd_p[i] = 0; |
| *pud_p = (pudval_t)pmd_p - __START_KERNEL_map + phys_base + _KERNPG_TABLE; |
| } |
| pmd = (physaddr & PMD_MASK) + early_pmd_flags; |
| pmd_p[pmd_index(address)] = pmd; |
| |
| return 0; |
| } |
| |
| /* Don't add a printk in there. printk relies on the PDA which is not initialized |
| yet. */ |
| static void __init clear_bss(void) |
| { |
| memset(__bss_start, 0, |
| (unsigned long) __bss_stop - (unsigned long) __bss_start); |
| } |
| |
| static unsigned long get_cmd_line_ptr(void) |
| { |
| unsigned long cmd_line_ptr = boot_params.hdr.cmd_line_ptr; |
| |
| cmd_line_ptr |= (u64)boot_params.ext_cmd_line_ptr << 32; |
| |
| return cmd_line_ptr; |
| } |
| |
| static void __init copy_bootdata(char *real_mode_data) |
| { |
| char * command_line; |
| unsigned long cmd_line_ptr; |
| |
| memcpy(&boot_params, real_mode_data, sizeof boot_params); |
| sanitize_boot_params(&boot_params); |
| cmd_line_ptr = get_cmd_line_ptr(); |
| if (cmd_line_ptr) { |
| command_line = __va(cmd_line_ptr); |
| memcpy(boot_command_line, command_line, COMMAND_LINE_SIZE); |
| } |
| } |
| |
| asmlinkage __visible void __init x86_64_start_kernel(char * real_mode_data) |
| { |
| int i; |
| |
| /* |
| * Build-time sanity checks on the kernel image and module |
| * area mappings. (these are purely build-time and produce no code) |
| */ |
| BUILD_BUG_ON(MODULES_VADDR < __START_KERNEL_map); |
| BUILD_BUG_ON(MODULES_VADDR - __START_KERNEL_map < KERNEL_IMAGE_SIZE); |
| BUILD_BUG_ON(MODULES_LEN + KERNEL_IMAGE_SIZE > 2*PUD_SIZE); |
| BUILD_BUG_ON((__START_KERNEL_map & ~PMD_MASK) != 0); |
| BUILD_BUG_ON((MODULES_VADDR & ~PMD_MASK) != 0); |
| BUILD_BUG_ON(!(MODULES_VADDR > __START_KERNEL)); |
| BUILD_BUG_ON(!(((MODULES_END - 1) & PGDIR_MASK) == |
| (__START_KERNEL & PGDIR_MASK))); |
| BUILD_BUG_ON(__fix_to_virt(__end_of_fixed_addresses) <= MODULES_END); |
| |
| /* Kill off the identity-map trampoline */ |
| reset_early_page_tables(); |
| |
| kasan_map_early_shadow(early_level4_pgt); |
| |
| /* clear bss before set_intr_gate with early_idt_handler */ |
| clear_bss(); |
| |
| for (i = 0; i < NUM_EXCEPTION_VECTORS; i++) |
| set_intr_gate(i, early_idt_handlers[i]); |
| load_idt((const struct desc_ptr *)&idt_descr); |
| |
| copy_bootdata(__va(real_mode_data)); |
| |
| /* |
| * Load microcode early on BSP. |
| */ |
| load_ucode_bsp(); |
| |
| if (console_loglevel >= CONSOLE_LOGLEVEL_DEBUG) |
| early_printk("Kernel alive\n"); |
| |
| clear_page(init_level4_pgt); |
| /* set init_level4_pgt kernel high mapping*/ |
| init_level4_pgt[511] = early_level4_pgt[511]; |
| |
| kasan_map_early_shadow(init_level4_pgt); |
| |
| x86_64_start_reservations(real_mode_data); |
| } |
| |
| void __init x86_64_start_reservations(char *real_mode_data) |
| { |
| /* version is always not zero if it is copied */ |
| if (!boot_params.hdr.version) |
| copy_bootdata(__va(real_mode_data)); |
| |
| reserve_ebda_region(); |
| |
| start_kernel(); |
| } |