diff options
| -rw-r--r-- | arch/i386/kernel/machine_kexec.c | 117 | ||||
| -rw-r--r-- | arch/i386/kernel/relocate_kernel.S | 162 | ||||
| -rw-r--r-- | include/asm-i386/kexec.h | 27 |
3 files changed, 201 insertions, 105 deletions
diff --git a/arch/i386/kernel/machine_kexec.c b/arch/i386/kernel/machine_kexec.c index 66c3dc99a65..91966bafb3d 100644 --- a/arch/i386/kernel/machine_kexec.c +++ b/arch/i386/kernel/machine_kexec.c @@ -21,70 +21,13 @@ #include <asm/system.h> #define PAGE_ALIGNED __attribute__ ((__aligned__(PAGE_SIZE))) - -#define L0_ATTR (_PAGE_PRESENT | _PAGE_RW | _PAGE_ACCESSED | _PAGE_DIRTY) -#define L1_ATTR (_PAGE_PRESENT | _PAGE_RW | _PAGE_ACCESSED | _PAGE_DIRTY) -#define L2_ATTR (_PAGE_PRESENT) - -#define LEVEL0_SIZE (1UL << 12UL) - -#ifndef CONFIG_X86_PAE -#define LEVEL1_SIZE (1UL << 22UL) -static u32 pgtable_level1[1024] PAGE_ALIGNED; - -static void identity_map_page(unsigned long address) -{ - unsigned long level1_index, level2_index; - u32 *pgtable_level2; - - /* Find the current page table */ - pgtable_level2 = __va(read_cr3()); - - /* Find the indexes of the physical address to identity map */ - level1_index = (address % LEVEL1_SIZE)/LEVEL0_SIZE; - level2_index = address / LEVEL1_SIZE; - - /* Identity map the page table entry */ - pgtable_level1[level1_index] = address | L0_ATTR; - pgtable_level2[level2_index] = __pa(pgtable_level1) | L1_ATTR; - - /* Flush the tlb so the new mapping takes effect. - * Global tlb entries are not flushed but that is not an issue. - */ - load_cr3(pgtable_level2); -} - -#else -#define LEVEL1_SIZE (1UL << 21UL) -#define LEVEL2_SIZE (1UL << 30UL) -static u64 pgtable_level1[512] PAGE_ALIGNED; -static u64 pgtable_level2[512] PAGE_ALIGNED; - -static void identity_map_page(unsigned long address) -{ - unsigned long level1_index, level2_index, level3_index; - u64 *pgtable_level3; - - /* Find the current page table */ - pgtable_level3 = __va(read_cr3()); - - /* Find the indexes of the physical address to identity map */ - level1_index = (address % LEVEL1_SIZE)/LEVEL0_SIZE; - level2_index = (address % LEVEL2_SIZE)/LEVEL1_SIZE; - level3_index = address / LEVEL2_SIZE; - - /* Identity map the page table entry */ - pgtable_level1[level1_index] = address | L0_ATTR; - pgtable_level2[level2_index] = __pa(pgtable_level1) | L1_ATTR; - set_64bit(&pgtable_level3[level3_index], - __pa(pgtable_level2) | L2_ATTR); - - /* Flush the tlb so the new mapping takes effect. - * Global tlb entries are not flushed but that is not an issue. - */ - load_cr3(pgtable_level3); -} +static u32 kexec_pgd[1024] PAGE_ALIGNED; +#ifdef CONFIG_X86_PAE +static u32 kexec_pmd0[1024] PAGE_ALIGNED; +static u32 kexec_pmd1[1024] PAGE_ALIGNED; #endif +static u32 kexec_pte0[1024] PAGE_ALIGNED; +static u32 kexec_pte1[1024] PAGE_ALIGNED; static void set_idt(void *newidt, __u16 limit) { @@ -128,16 +71,6 @@ static void load_segments(void) #undef __STR } -typedef asmlinkage NORET_TYPE void (*relocate_new_kernel_t)( - unsigned long indirection_page, - unsigned long reboot_code_buffer, - unsigned long start_address, - unsigned int has_pae) ATTRIB_NORET; - -extern const unsigned char relocate_new_kernel[]; -extern void relocate_new_kernel_end(void); -extern const unsigned int relocate_new_kernel_size; - /* * A architecture hook called to validate the * proposed image and prepare the control pages @@ -170,25 +103,29 @@ void machine_kexec_cleanup(struct kimage *image) */ NORET_TYPE void machine_kexec(struct kimage *image) { - unsigned long page_list; - unsigned long reboot_code_buffer; - - relocate_new_kernel_t rnk; + unsigned long page_list[PAGES_NR]; + void *control_page; /* Interrupts aren't acceptable while we reboot */ local_irq_disable(); - /* Compute some offsets */ - reboot_code_buffer = page_to_pfn(image->control_code_page) - << PAGE_SHIFT; - page_list = image->head; - - /* Set up an identity mapping for the reboot_code_buffer */ - identity_map_page(reboot_code_buffer); - - /* copy it out */ - memcpy((void *)reboot_code_buffer, relocate_new_kernel, - relocate_new_kernel_size); + control_page = page_address(image->control_code_page); + memcpy(control_page, relocate_kernel, PAGE_SIZE); + + page_list[PA_CONTROL_PAGE] = __pa(control_page); + page_list[VA_CONTROL_PAGE] = (unsigned long)relocate_kernel; + page_list[PA_PGD] = __pa(kexec_pgd); + page_list[VA_PGD] = (unsigned long)kexec_pgd; +#ifdef CONFIG_X86_PAE + page_list[PA_PMD_0] = __pa(kexec_pmd0); + page_list[VA_PMD_0] = (unsigned long)kexec_pmd0; + page_list[PA_PMD_1] = __pa(kexec_pmd1); + page_list[VA_PMD_1] = (unsigned long)kexec_pmd1; +#endif + page_list[PA_PTE_0] = __pa(kexec_pte0); + page_list[VA_PTE_0] = (unsigned long)kexec_pte0; + page_list[PA_PTE_1] = __pa(kexec_pte1); + page_list[VA_PTE_1] = (unsigned long)kexec_pte1; /* The segment registers are funny things, they have both a * visible and an invisible part. Whenever the visible part is @@ -207,8 +144,8 @@ NORET_TYPE void machine_kexec(struct kimage *image) set_idt(phys_to_virt(0),0); /* now call it */ - rnk = (relocate_new_kernel_t) reboot_code_buffer; - (*rnk)(page_list, reboot_code_buffer, image->start, cpu_has_pae); + relocate_kernel((unsigned long)image->head, (unsigned long)page_list, + image->start, cpu_has_pae); } /* crashkernel=size@addr specifies the location to reserve for diff --git a/arch/i386/kernel/relocate_kernel.S b/arch/i386/kernel/relocate_kernel.S index d312616effa..f151d6fae46 100644 --- a/arch/i386/kernel/relocate_kernel.S +++ b/arch/i386/kernel/relocate_kernel.S @@ -7,16 +7,138 @@ */ #include <linux/linkage.h> +#include <asm/page.h> +#include <asm/kexec.h> + +/* + * Must be relocatable PIC code callable as a C function + */ + +#define PTR(x) (x << 2) +#define PAGE_ALIGNED (1 << PAGE_SHIFT) +#define PAGE_ATTR 0x63 /* _PAGE_PRESENT|_PAGE_RW|_PAGE_ACCESSED|_PAGE_DIRTY */ +#define PAE_PGD_ATTR 0x01 /* _PAGE_PRESENT */ + + .text + .align PAGE_ALIGNED + .globl relocate_kernel +relocate_kernel: + movl 8(%esp), %ebp /* list of pages */ + +#ifdef CONFIG_X86_PAE + /* map the control page at its virtual address */ + + movl PTR(VA_PGD)(%ebp), %edi + movl PTR(VA_CONTROL_PAGE)(%ebp), %eax + andl $0xc0000000, %eax + shrl $27, %eax + addl %edi, %eax + + movl PTR(PA_PMD_0)(%ebp), %edx + orl $PAE_PGD_ATTR, %edx + movl %edx, (%eax) + + movl PTR(VA_PMD_0)(%ebp), %edi + movl PTR(VA_CONTROL_PAGE)(%ebp), %eax + andl $0x3fe00000, %eax + shrl $18, %eax + addl %edi, %eax + + movl PTR(PA_PTE_0)(%ebp), %edx + orl $PAGE_ATTR, %edx + movl %edx, (%eax) + + movl PTR(VA_PTE_0)(%ebp), %edi + movl PTR(VA_CONTROL_PAGE)(%ebp), %eax + andl $0x001ff000, %eax + shrl $9, %eax + addl %edi, %eax + + movl PTR(PA_CONTROL_PAGE)(%ebp), %edx + orl $PAGE_ATTR, %edx + movl %edx, (%eax) + + /* identity map the control page at its physical address */ + + movl PTR(VA_PGD)(%ebp), %edi + movl PTR(PA_CONTROL_PAGE)(%ebp), %eax + andl $0xc0000000, %eax + shrl $27, %eax + addl %edi, %eax + + movl PTR(PA_PMD_1)(%ebp), %edx + orl $PAE_PGD_ATTR, %edx + movl %edx, (%eax) + + movl PTR(VA_PMD_1)(%ebp), %edi + movl PTR(PA_CONTROL_PAGE)(%ebp), %eax + andl $0x3fe00000, %eax + shrl $18, %eax + addl %edi, %eax + + movl PTR(PA_PTE_1)(%ebp), %edx + orl $PAGE_ATTR, %edx + movl %edx, (%eax) + + movl PTR(VA_PTE_1)(%ebp), %edi + movl PTR(PA_CONTROL_PAGE)(%ebp), %eax + andl $0x001ff000, %eax + shrl $9, %eax + addl %edi, %eax + + movl PTR(PA_CONTROL_PAGE)(%ebp), %edx + orl $PAGE_ATTR, %edx + movl %edx, (%eax) +#else + /* map the control page at its virtual address */ + + movl PTR(VA_PGD)(%ebp), %edi + movl PTR(VA_CONTROL_PAGE)(%ebp), %eax + andl $0xffc00000, %eax + shrl $20, %eax + addl %edi, %eax + + movl PTR(PA_PTE_0)(%ebp), %edx + orl $PAGE_ATTR, %edx + movl %edx, (%eax) + + movl PTR(VA_PTE_0)(%ebp), %edi + movl PTR(VA_CONTROL_PAGE)(%ebp), %eax + andl $0x003ff000, %eax + shrl $10, %eax + addl %edi, %eax + + movl PTR(PA_CONTROL_PAGE)(%ebp), %edx + orl $PAGE_ATTR, %edx + movl %edx, (%eax) + + /* identity map the control page at its physical address */ + + movl PTR(VA_PGD)(%ebp), %edi + movl PTR(PA_CONTROL_PAGE)(%ebp), %eax + andl $0xffc00000, %eax + shrl $20, %eax + addl %edi, %eax + + movl PTR(PA_PTE_1)(%ebp), %edx + orl $PAGE_ATTR, %edx + movl %edx, (%eax) + + movl PTR(VA_PTE_1)(%ebp), %edi + movl PTR(PA_CONTROL_PAGE)(%ebp), %eax + andl $0x003ff000, %eax + shrl $10, %eax + addl %edi, %eax + + movl PTR(PA_CONTROL_PAGE)(%ebp), %edx + orl $PAGE_ATTR, %edx + movl %edx, (%eax) +#endif - /* - * Must be relocatable PIC code callable as a C function, that once - * it starts can not use the previous processes stack. - */ - .globl relocate_new_kernel relocate_new_kernel: /* read the arguments and say goodbye to the stack */ movl 4(%esp), %ebx /* page_list */ - movl 8(%esp), %ebp /* reboot_code_buffer */ + movl 8(%esp), %ebp /* list of pages */ movl 12(%esp), %edx /* start address */ movl 16(%esp), %ecx /* cpu_has_pae */ @@ -24,11 +146,26 @@ relocate_new_kernel: pushl $0 popfl - /* set a new stack at the bottom of our page... */ - lea 4096(%ebp), %esp + /* get physical address of control page now */ + /* this is impossible after page table switch */ + movl PTR(PA_CONTROL_PAGE)(%ebp), %edi - /* store the parameters back on the stack */ - pushl %edx /* store the start address */ + /* switch to new set of page tables */ + movl PTR(PA_PGD)(%ebp), %eax + movl %eax, %cr3 + + /* setup a new stack at the end of the physical control page */ + lea 4096(%edi), %esp + + /* jump to identity mapped page */ + movl %edi, %eax + addl $(identity_mapped - relocate_kernel), %eax + pushl %eax + ret + +identity_mapped: + /* store the start address on the stack */ + pushl %edx /* Set cr0 to a known state: * 31 0 == Paging disabled @@ -113,8 +250,3 @@ relocate_new_kernel: xorl %edi, %edi xorl %ebp, %ebp ret -relocate_new_kernel_end: - - .globl relocate_new_kernel_size -relocate_new_kernel_size: - .long relocate_new_kernel_end - relocate_new_kernel diff --git a/include/asm-i386/kexec.h b/include/asm-i386/kexec.h index 53f0e06672d..4dfc9f5ed03 100644 --- a/include/asm-i386/kexec.h +++ b/include/asm-i386/kexec.h @@ -1,6 +1,26 @@ #ifndef _I386_KEXEC_H #define _I386_KEXEC_H +#define PA_CONTROL_PAGE 0 +#define VA_CONTROL_PAGE 1 +#define PA_PGD 2 +#define VA_PGD 3 +#define PA_PTE_0 4 +#define VA_PTE_0 5 +#define PA_PTE_1 6 +#define VA_PTE_1 7 +#ifdef CONFIG_X86_PAE +#define PA_PMD_0 8 +#define VA_PMD_0 9 +#define PA_PMD_1 10 +#define VA_PMD_1 11 +#define PAGES_NR 12 +#else +#define PAGES_NR 8 +#endif + +#ifndef __ASSEMBLY__ + #include <asm/fixmap.h> #include <asm/ptrace.h> #include <asm/string.h> @@ -72,5 +92,12 @@ static inline void crash_setup_regs(struct pt_regs *newregs, newregs->eip = (unsigned long)current_text_addr(); } } +asmlinkage NORET_TYPE void +relocate_kernel(unsigned long indirection_page, + unsigned long control_page, + unsigned long start_address, + unsigned int has_pae) ATTRIB_NORET; + +#endif /* __ASSEMBLY__ */ #endif /* _I386_KEXEC_H */ |