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authorSrikant Patnaik2015-01-11 12:28:04 +0530
committerSrikant Patnaik2015-01-11 12:28:04 +0530
commit871480933a1c28f8a9fed4c4d34d06c439a7a422 (patch)
tree8718f573808810c2a1e8cb8fb6ac469093ca2784 /arch/x86/kernel/machine_kexec_64.c
parent9d40ac5867b9aefe0722bc1f110b965ff294d30d (diff)
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Moved, renamed, and deleted files
The original directory structure was scattered and unorganized. Changes are basically to make it look like kernel structure.
Diffstat (limited to 'arch/x86/kernel/machine_kexec_64.c')
-rw-r--r--arch/x86/kernel/machine_kexec_64.c356
1 files changed, 356 insertions, 0 deletions
diff --git a/arch/x86/kernel/machine_kexec_64.c b/arch/x86/kernel/machine_kexec_64.c
new file mode 100644
index 00000000..b3ea9db3
--- /dev/null
+++ b/arch/x86/kernel/machine_kexec_64.c
@@ -0,0 +1,356 @@
+/*
+ * handle transition of Linux booting another kernel
+ * Copyright (C) 2002-2005 Eric Biederman <ebiederm@xmission.com>
+ *
+ * This source code is licensed under the GNU General Public License,
+ * Version 2. See the file COPYING for more details.
+ */
+
+#include <linux/mm.h>
+#include <linux/kexec.h>
+#include <linux/string.h>
+#include <linux/gfp.h>
+#include <linux/reboot.h>
+#include <linux/numa.h>
+#include <linux/ftrace.h>
+#include <linux/io.h>
+#include <linux/suspend.h>
+
+#include <asm/pgtable.h>
+#include <asm/tlbflush.h>
+#include <asm/mmu_context.h>
+#include <asm/debugreg.h>
+
+static int init_one_level2_page(struct kimage *image, pgd_t *pgd,
+ unsigned long addr)
+{
+ pud_t *pud;
+ pmd_t *pmd;
+ struct page *page;
+ int result = -ENOMEM;
+
+ addr &= PMD_MASK;
+ pgd += pgd_index(addr);
+ if (!pgd_present(*pgd)) {
+ page = kimage_alloc_control_pages(image, 0);
+ if (!page)
+ goto out;
+ pud = (pud_t *)page_address(page);
+ clear_page(pud);
+ set_pgd(pgd, __pgd(__pa(pud) | _KERNPG_TABLE));
+ }
+ pud = pud_offset(pgd, addr);
+ if (!pud_present(*pud)) {
+ page = kimage_alloc_control_pages(image, 0);
+ if (!page)
+ goto out;
+ pmd = (pmd_t *)page_address(page);
+ clear_page(pmd);
+ set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE));
+ }
+ pmd = pmd_offset(pud, addr);
+ if (!pmd_present(*pmd))
+ set_pmd(pmd, __pmd(addr | __PAGE_KERNEL_LARGE_EXEC));
+ result = 0;
+out:
+ return result;
+}
+
+static void init_level2_page(pmd_t *level2p, unsigned long addr)
+{
+ unsigned long end_addr;
+
+ addr &= PAGE_MASK;
+ end_addr = addr + PUD_SIZE;
+ while (addr < end_addr) {
+ set_pmd(level2p++, __pmd(addr | __PAGE_KERNEL_LARGE_EXEC));
+ addr += PMD_SIZE;
+ }
+}
+
+static int init_level3_page(struct kimage *image, pud_t *level3p,
+ unsigned long addr, unsigned long last_addr)
+{
+ unsigned long end_addr;
+ int result;
+
+ result = 0;
+ addr &= PAGE_MASK;
+ end_addr = addr + PGDIR_SIZE;
+ while ((addr < last_addr) && (addr < end_addr)) {
+ struct page *page;
+ pmd_t *level2p;
+
+ page = kimage_alloc_control_pages(image, 0);
+ if (!page) {
+ result = -ENOMEM;
+ goto out;
+ }
+ level2p = (pmd_t *)page_address(page);
+ init_level2_page(level2p, addr);
+ set_pud(level3p++, __pud(__pa(level2p) | _KERNPG_TABLE));
+ addr += PUD_SIZE;
+ }
+ /* clear the unused entries */
+ while (addr < end_addr) {
+ pud_clear(level3p++);
+ addr += PUD_SIZE;
+ }
+out:
+ return result;
+}
+
+
+static int init_level4_page(struct kimage *image, pgd_t *level4p,
+ unsigned long addr, unsigned long last_addr)
+{
+ unsigned long end_addr;
+ int result;
+
+ result = 0;
+ addr &= PAGE_MASK;
+ end_addr = addr + (PTRS_PER_PGD * PGDIR_SIZE);
+ while ((addr < last_addr) && (addr < end_addr)) {
+ struct page *page;
+ pud_t *level3p;
+
+ page = kimage_alloc_control_pages(image, 0);
+ if (!page) {
+ result = -ENOMEM;
+ goto out;
+ }
+ level3p = (pud_t *)page_address(page);
+ result = init_level3_page(image, level3p, addr, last_addr);
+ if (result)
+ goto out;
+ set_pgd(level4p++, __pgd(__pa(level3p) | _KERNPG_TABLE));
+ addr += PGDIR_SIZE;
+ }
+ /* clear the unused entries */
+ while (addr < end_addr) {
+ pgd_clear(level4p++);
+ addr += PGDIR_SIZE;
+ }
+out:
+ return result;
+}
+
+static void free_transition_pgtable(struct kimage *image)
+{
+ free_page((unsigned long)image->arch.pud);
+ free_page((unsigned long)image->arch.pmd);
+ free_page((unsigned long)image->arch.pte);
+}
+
+static int init_transition_pgtable(struct kimage *image, pgd_t *pgd)
+{
+ pud_t *pud;
+ pmd_t *pmd;
+ pte_t *pte;
+ unsigned long vaddr, paddr;
+ int result = -ENOMEM;
+
+ vaddr = (unsigned long)relocate_kernel;
+ paddr = __pa(page_address(image->control_code_page)+PAGE_SIZE);
+ pgd += pgd_index(vaddr);
+ if (!pgd_present(*pgd)) {
+ pud = (pud_t *)get_zeroed_page(GFP_KERNEL);
+ if (!pud)
+ goto err;
+ image->arch.pud = pud;
+ set_pgd(pgd, __pgd(__pa(pud) | _KERNPG_TABLE));
+ }
+ pud = pud_offset(pgd, vaddr);
+ if (!pud_present(*pud)) {
+ pmd = (pmd_t *)get_zeroed_page(GFP_KERNEL);
+ if (!pmd)
+ goto err;
+ image->arch.pmd = pmd;
+ set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE));
+ }
+ pmd = pmd_offset(pud, vaddr);
+ if (!pmd_present(*pmd)) {
+ pte = (pte_t *)get_zeroed_page(GFP_KERNEL);
+ if (!pte)
+ goto err;
+ image->arch.pte = pte;
+ set_pmd(pmd, __pmd(__pa(pte) | _KERNPG_TABLE));
+ }
+ pte = pte_offset_kernel(pmd, vaddr);
+ set_pte(pte, pfn_pte(paddr >> PAGE_SHIFT, PAGE_KERNEL_EXEC));
+ return 0;
+err:
+ free_transition_pgtable(image);
+ return result;
+}
+
+
+static int init_pgtable(struct kimage *image, unsigned long start_pgtable)
+{
+ pgd_t *level4p;
+ int result;
+ level4p = (pgd_t *)__va(start_pgtable);
+ result = init_level4_page(image, level4p, 0, max_pfn << PAGE_SHIFT);
+ if (result)
+ return result;
+ /*
+ * image->start may be outside 0 ~ max_pfn, for example when
+ * jump back to original kernel from kexeced kernel
+ */
+ result = init_one_level2_page(image, level4p, image->start);
+ if (result)
+ return result;
+ return init_transition_pgtable(image, level4p);
+}
+
+static void set_idt(void *newidt, u16 limit)
+{
+ struct desc_ptr curidt;
+
+ /* x86-64 supports unaliged loads & stores */
+ curidt.size = limit;
+ curidt.address = (unsigned long)newidt;
+
+ __asm__ __volatile__ (
+ "lidtq %0\n"
+ : : "m" (curidt)
+ );
+};
+
+
+static void set_gdt(void *newgdt, u16 limit)
+{
+ struct desc_ptr curgdt;
+
+ /* x86-64 supports unaligned loads & stores */
+ curgdt.size = limit;
+ curgdt.address = (unsigned long)newgdt;
+
+ __asm__ __volatile__ (
+ "lgdtq %0\n"
+ : : "m" (curgdt)
+ );
+};
+
+static void load_segments(void)
+{
+ __asm__ __volatile__ (
+ "\tmovl %0,%%ds\n"
+ "\tmovl %0,%%es\n"
+ "\tmovl %0,%%ss\n"
+ "\tmovl %0,%%fs\n"
+ "\tmovl %0,%%gs\n"
+ : : "a" (__KERNEL_DS) : "memory"
+ );
+}
+
+int machine_kexec_prepare(struct kimage *image)
+{
+ unsigned long start_pgtable;
+ int result;
+
+ /* Calculate the offsets */
+ start_pgtable = page_to_pfn(image->control_code_page) << PAGE_SHIFT;
+
+ /* Setup the identity mapped 64bit page table */
+ result = init_pgtable(image, start_pgtable);
+ if (result)
+ return result;
+
+ return 0;
+}
+
+void machine_kexec_cleanup(struct kimage *image)
+{
+ free_transition_pgtable(image);
+}
+
+/*
+ * Do not allocate memory (or fail in any way) in machine_kexec().
+ * We are past the point of no return, committed to rebooting now.
+ */
+void machine_kexec(struct kimage *image)
+{
+ unsigned long page_list[PAGES_NR];
+ void *control_page;
+ int save_ftrace_enabled;
+
+#ifdef CONFIG_KEXEC_JUMP
+ if (image->preserve_context)
+ save_processor_state();
+#endif
+
+ save_ftrace_enabled = __ftrace_enabled_save();
+
+ /* Interrupts aren't acceptable while we reboot */
+ local_irq_disable();
+ hw_breakpoint_disable();
+
+ if (image->preserve_context) {
+#ifdef CONFIG_X86_IO_APIC
+ /*
+ * We need to put APICs in legacy mode so that we can
+ * get timer interrupts in second kernel. kexec/kdump
+ * paths already have calls to disable_IO_APIC() in
+ * one form or other. kexec jump path also need
+ * one.
+ */
+ disable_IO_APIC();
+#endif
+ }
+
+ control_page = page_address(image->control_code_page) + PAGE_SIZE;
+ memcpy(control_page, relocate_kernel, KEXEC_CONTROL_CODE_MAX_SIZE);
+
+ page_list[PA_CONTROL_PAGE] = virt_to_phys(control_page);
+ page_list[VA_CONTROL_PAGE] = (unsigned long)control_page;
+ page_list[PA_TABLE_PAGE] =
+ (unsigned long)__pa(page_address(image->control_code_page));
+
+ if (image->type == KEXEC_TYPE_DEFAULT)
+ page_list[PA_SWAP_PAGE] = (page_to_pfn(image->swap_page)
+ << PAGE_SHIFT);
+
+ /*
+ * The segment registers are funny things, they have both a
+ * visible and an invisible part. Whenever the visible part is
+ * set to a specific selector, the invisible part is loaded
+ * with from a table in memory. At no other time is the
+ * descriptor table in memory accessed.
+ *
+ * I take advantage of this here by force loading the
+ * segments, before I zap the gdt with an invalid value.
+ */
+ load_segments();
+ /*
+ * The gdt & idt are now invalid.
+ * If you want to load them you must set up your own idt & gdt.
+ */
+ set_gdt(phys_to_virt(0), 0);
+ set_idt(phys_to_virt(0), 0);
+
+ /* now call it */
+ image->start = relocate_kernel((unsigned long)image->head,
+ (unsigned long)page_list,
+ image->start,
+ image->preserve_context);
+
+#ifdef CONFIG_KEXEC_JUMP
+ if (image->preserve_context)
+ restore_processor_state();
+#endif
+
+ __ftrace_enabled_restore(save_ftrace_enabled);
+}
+
+void arch_crash_save_vmcoreinfo(void)
+{
+ VMCOREINFO_SYMBOL(phys_base);
+ VMCOREINFO_SYMBOL(init_level4_pgt);
+
+#ifdef CONFIG_NUMA
+ VMCOREINFO_SYMBOL(node_data);
+ VMCOREINFO_LENGTH(node_data, MAX_NUMNODES);
+#endif
+}
+