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![Dave Jones](/assets/img/avatar_default.png)
Since the x86 merge, lots of files that referenced their own filenames are no longer correct. Rather than keep them up to date, just delete them, as they add no real value. Additionally: - fix up comment formatting in scx200_32.c - Remove a credit from myself in setup_64.c from a time when we had no SCM - remove longwinded history from tsc_32.c which can be figured out from git. Signed-off-by: Dave Jones <davej@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
259 lines
6.5 KiB
C
259 lines
6.5 KiB
C
/*
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* handle transition of Linux booting another kernel
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* Copyright (C) 2002-2005 Eric Biederman <ebiederm@xmission.com>
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*
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* This source code is licensed under the GNU General Public License,
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* Version 2. See the file COPYING for more details.
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*/
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#include <linux/mm.h>
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#include <linux/kexec.h>
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#include <linux/string.h>
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#include <linux/reboot.h>
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#include <asm/pgtable.h>
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#include <asm/tlbflush.h>
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#include <asm/mmu_context.h>
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#include <asm/io.h>
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#define PAGE_ALIGNED __attribute__ ((__aligned__(PAGE_SIZE)))
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static u64 kexec_pgd[512] PAGE_ALIGNED;
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static u64 kexec_pud0[512] PAGE_ALIGNED;
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static u64 kexec_pmd0[512] PAGE_ALIGNED;
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static u64 kexec_pte0[512] PAGE_ALIGNED;
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static u64 kexec_pud1[512] PAGE_ALIGNED;
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static u64 kexec_pmd1[512] PAGE_ALIGNED;
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static u64 kexec_pte1[512] PAGE_ALIGNED;
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static void init_level2_page(pmd_t *level2p, unsigned long addr)
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{
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unsigned long end_addr;
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addr &= PAGE_MASK;
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end_addr = addr + PUD_SIZE;
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while (addr < end_addr) {
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set_pmd(level2p++, __pmd(addr | __PAGE_KERNEL_LARGE_EXEC));
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addr += PMD_SIZE;
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}
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}
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static int init_level3_page(struct kimage *image, pud_t *level3p,
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unsigned long addr, unsigned long last_addr)
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{
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unsigned long end_addr;
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int result;
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result = 0;
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addr &= PAGE_MASK;
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end_addr = addr + PGDIR_SIZE;
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while ((addr < last_addr) && (addr < end_addr)) {
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struct page *page;
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pmd_t *level2p;
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page = kimage_alloc_control_pages(image, 0);
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if (!page) {
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result = -ENOMEM;
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goto out;
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}
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level2p = (pmd_t *)page_address(page);
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init_level2_page(level2p, addr);
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set_pud(level3p++, __pud(__pa(level2p) | _KERNPG_TABLE));
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addr += PUD_SIZE;
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}
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/* clear the unused entries */
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while (addr < end_addr) {
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pud_clear(level3p++);
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addr += PUD_SIZE;
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}
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out:
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return result;
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}
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static int init_level4_page(struct kimage *image, pgd_t *level4p,
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unsigned long addr, unsigned long last_addr)
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{
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unsigned long end_addr;
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int result;
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result = 0;
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addr &= PAGE_MASK;
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end_addr = addr + (PTRS_PER_PGD * PGDIR_SIZE);
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while ((addr < last_addr) && (addr < end_addr)) {
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struct page *page;
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pud_t *level3p;
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page = kimage_alloc_control_pages(image, 0);
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if (!page) {
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result = -ENOMEM;
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goto out;
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}
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level3p = (pud_t *)page_address(page);
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result = init_level3_page(image, level3p, addr, last_addr);
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if (result) {
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goto out;
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}
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set_pgd(level4p++, __pgd(__pa(level3p) | _KERNPG_TABLE));
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addr += PGDIR_SIZE;
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}
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/* clear the unused entries */
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while (addr < end_addr) {
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pgd_clear(level4p++);
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addr += PGDIR_SIZE;
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}
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out:
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return result;
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}
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static int init_pgtable(struct kimage *image, unsigned long start_pgtable)
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{
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pgd_t *level4p;
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level4p = (pgd_t *)__va(start_pgtable);
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return init_level4_page(image, level4p, 0, end_pfn << PAGE_SHIFT);
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}
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static void set_idt(void *newidt, u16 limit)
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{
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struct desc_ptr curidt;
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/* x86-64 supports unaliged loads & stores */
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curidt.size = limit;
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curidt.address = (unsigned long)newidt;
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__asm__ __volatile__ (
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"lidtq %0\n"
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: : "m" (curidt)
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);
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};
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static void set_gdt(void *newgdt, u16 limit)
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{
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struct desc_ptr curgdt;
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/* x86-64 supports unaligned loads & stores */
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curgdt.size = limit;
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curgdt.address = (unsigned long)newgdt;
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__asm__ __volatile__ (
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"lgdtq %0\n"
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: : "m" (curgdt)
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);
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};
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static void load_segments(void)
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{
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__asm__ __volatile__ (
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"\tmovl %0,%%ds\n"
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"\tmovl %0,%%es\n"
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"\tmovl %0,%%ss\n"
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"\tmovl %0,%%fs\n"
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"\tmovl %0,%%gs\n"
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: : "a" (__KERNEL_DS) : "memory"
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);
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}
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int machine_kexec_prepare(struct kimage *image)
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{
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unsigned long start_pgtable;
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int result;
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/* Calculate the offsets */
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start_pgtable = page_to_pfn(image->control_code_page) << PAGE_SHIFT;
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/* Setup the identity mapped 64bit page table */
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result = init_pgtable(image, start_pgtable);
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if (result)
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return result;
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return 0;
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}
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void machine_kexec_cleanup(struct kimage *image)
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{
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return;
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}
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/*
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* Do not allocate memory (or fail in any way) in machine_kexec().
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* We are past the point of no return, committed to rebooting now.
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*/
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NORET_TYPE void machine_kexec(struct kimage *image)
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{
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unsigned long page_list[PAGES_NR];
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void *control_page;
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/* Interrupts aren't acceptable while we reboot */
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local_irq_disable();
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control_page = page_address(image->control_code_page) + PAGE_SIZE;
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memcpy(control_page, relocate_kernel, PAGE_SIZE);
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page_list[PA_CONTROL_PAGE] = virt_to_phys(control_page);
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page_list[VA_CONTROL_PAGE] = (unsigned long)relocate_kernel;
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page_list[PA_PGD] = virt_to_phys(&kexec_pgd);
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page_list[VA_PGD] = (unsigned long)kexec_pgd;
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page_list[PA_PUD_0] = virt_to_phys(&kexec_pud0);
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page_list[VA_PUD_0] = (unsigned long)kexec_pud0;
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page_list[PA_PMD_0] = virt_to_phys(&kexec_pmd0);
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page_list[VA_PMD_0] = (unsigned long)kexec_pmd0;
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page_list[PA_PTE_0] = virt_to_phys(&kexec_pte0);
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page_list[VA_PTE_0] = (unsigned long)kexec_pte0;
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page_list[PA_PUD_1] = virt_to_phys(&kexec_pud1);
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page_list[VA_PUD_1] = (unsigned long)kexec_pud1;
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page_list[PA_PMD_1] = virt_to_phys(&kexec_pmd1);
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page_list[VA_PMD_1] = (unsigned long)kexec_pmd1;
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page_list[PA_PTE_1] = virt_to_phys(&kexec_pte1);
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page_list[VA_PTE_1] = (unsigned long)kexec_pte1;
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page_list[PA_TABLE_PAGE] =
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(unsigned long)__pa(page_address(image->control_code_page));
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/* The segment registers are funny things, they have both a
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* visible and an invisible part. Whenever the visible part is
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* set to a specific selector, the invisible part is loaded
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* with from a table in memory. At no other time is the
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* descriptor table in memory accessed.
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*
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* I take advantage of this here by force loading the
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* segments, before I zap the gdt with an invalid value.
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*/
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load_segments();
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/* The gdt & idt are now invalid.
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* If you want to load them you must set up your own idt & gdt.
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*/
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set_gdt(phys_to_virt(0),0);
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set_idt(phys_to_virt(0),0);
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/* now call it */
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relocate_kernel((unsigned long)image->head, (unsigned long)page_list,
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image->start);
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}
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/* crashkernel=size@addr specifies the location to reserve for
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* a crash kernel. By reserving this memory we guarantee
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* that linux never set's it up as a DMA target.
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* Useful for holding code to do something appropriate
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* after a kernel panic.
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*/
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static int __init setup_crashkernel(char *arg)
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{
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unsigned long size, base;
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char *p;
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if (!arg)
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return -EINVAL;
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size = memparse(arg, &p);
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if (arg == p)
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return -EINVAL;
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if (*p == '@') {
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base = memparse(p+1, &p);
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/* FIXME: Do I want a sanity check to validate the
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* memory range? Yes you do, but it's too early for
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* e820 -AK */
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crashk_res.start = base;
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crashk_res.end = base + size - 1;
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}
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return 0;
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}
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early_param("crashkernel", setup_crashkernel);
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