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author | Srikant Patnaik | 2015-01-11 12:28:04 +0530 |
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committer | Srikant Patnaik | 2015-01-11 12:28:04 +0530 |
commit | 871480933a1c28f8a9fed4c4d34d06c439a7a422 (patch) | |
tree | 8718f573808810c2a1e8cb8fb6ac469093ca2784 /arch/x86/kernel/machine_kexec_64.c | |
parent | 9d40ac5867b9aefe0722bc1f110b965ff294d30d (diff) | |
download | FOSSEE-netbook-kernel-source-871480933a1c28f8a9fed4c4d34d06c439a7a422.tar.gz FOSSEE-netbook-kernel-source-871480933a1c28f8a9fed4c4d34d06c439a7a422.tar.bz2 FOSSEE-netbook-kernel-source-871480933a1c28f8a9fed4c4d34d06c439a7a422.zip |
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.c | 356 |
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 +} + |