LXR linux/arch/x86/include/asm/kexec.h

   1#ifndef _ASM_X86_KEXEC_H
   2#define _ASM_X86_KEXEC_H
   3
   4#ifdef CONFIG_X86_32
   5# define PA_CONTROL_PAGE        0
   6# define VA_CONTROL_PAGE        1
   7# define PA_PGD                 2
   8# define PA_SWAP_PAGE           3
   9# define PAGES_NR               4
  10#else
  11# define PA_CONTROL_PAGE        0
  12# define VA_CONTROL_PAGE        1
  13# define PA_TABLE_PAGE          2
  14# define PA_SWAP_PAGE           3
  15# define PAGES_NR               4
  16#endif
  17
  18# define KEXEC_CONTROL_CODE_MAX_SIZE    2048
  19
  20#ifndef __ASSEMBLY__
  21
  22#include <linux/string.h>
  23
  24#include <asm/page.h>
  25#include <asm/ptrace.h>
  26#include <asm/bootparam.h>
  27
  28struct kimage;
  29
  30/*
  31 * KEXEC_SOURCE_MEMORY_LIMIT maximum page get_free_page can return.
  32 * I.e. Maximum page that is mapped directly into kernel memory,
  33 * and kmap is not required.
  34 *
  35 * So far x86_64 is limited to 40 physical address bits.
  36 */
  37#ifdef CONFIG_X86_32
  38/* Maximum physical address we can use pages from */
  39# define KEXEC_SOURCE_MEMORY_LIMIT (-1UL)
  40/* Maximum address we can reach in physical address mode */
  41# define KEXEC_DESTINATION_MEMORY_LIMIT (-1UL)
  42/* Maximum address we can use for the control code buffer */
  43# define KEXEC_CONTROL_MEMORY_LIMIT TASK_SIZE
  44
  45# define KEXEC_CONTROL_PAGE_SIZE        4096
  46
  47/* The native architecture */
  48# define KEXEC_ARCH KEXEC_ARCH_386
  49
  50/* We can also handle crash dumps from 64 bit kernel. */
  51# define vmcore_elf_check_arch_cross(x) ((x)->e_machine == EM_X86_64)
  52#else
  53/* Maximum physical address we can use pages from */
  54# define KEXEC_SOURCE_MEMORY_LIMIT      (MAXMEM-1)
  55/* Maximum address we can reach in physical address mode */
  56# define KEXEC_DESTINATION_MEMORY_LIMIT (MAXMEM-1)
  57/* Maximum address we can use for the control pages */
  58# define KEXEC_CONTROL_MEMORY_LIMIT     (MAXMEM-1)
  59
  60/* Allocate one page for the pdp and the second for the code */
  61# define KEXEC_CONTROL_PAGE_SIZE  (4096UL + 4096UL)
  62
  63/* The native architecture */
  64# define KEXEC_ARCH KEXEC_ARCH_X86_64
  65#endif
  66
  67/* Memory to backup during crash kdump */
  68#define KEXEC_BACKUP_SRC_START  (0UL)
  69#define KEXEC_BACKUP_SRC_END    (640 * 1024UL)  /* 640K */
  70
  71/*
  72 * CPU does not save ss and sp on stack if execution is already
  73 * running in kernel mode at the time of NMI occurrence. This code
  74 * fixes it.
  75 */
  76static inline void crash_fixup_ss_esp(struct pt_regs *newregs,
  77                                      struct pt_regs *oldregs)
  78{
  79#ifdef CONFIG_X86_32
  80        newregs->sp = (unsigned long)&(oldregs->sp);
  81        asm volatile("xorl %%eax, %%eax\n\t"
  82                     "movw %%ss, %%ax\n\t"
  83                     :"=a"(newregs->ss));
  84#endif
  85}
  86
  87/*
  88 * This function is responsible for capturing register states if coming
  89 * via panic otherwise just fix up the ss and sp if coming via kernel
  90 * mode exception.
  91 */
  92static inline void crash_setup_regs(struct pt_regs *newregs,
  93                                    struct pt_regs *oldregs)
  94{
  95        if (oldregs) {
  96                memcpy(newregs, oldregs, sizeof(*newregs));
  97                crash_fixup_ss_esp(newregs, oldregs);
  98        } else {
  99#ifdef CONFIG_X86_32
 100                asm volatile("movl %%ebx,%0" : "=m"(newregs->bx));
 101                asm volatile("movl %%ecx,%0" : "=m"(newregs->cx));
 102                asm volatile("movl %%edx,%0" : "=m"(newregs->dx));
 103                asm volatile("movl %%esi,%0" : "=m"(newregs->si));
 104                asm volatile("movl %%edi,%0" : "=m"(newregs->di));
 105                asm volatile("movl %%ebp,%0" : "=m"(newregs->bp));
 106                asm volatile("movl %%eax,%0" : "=m"(newregs->ax));
 107                asm volatile("movl %%esp,%0" : "=m"(newregs->sp));
 108                asm volatile("movl %%ss, %%eax;" :"=a"(newregs->ss));
 109                asm volatile("movl %%cs, %%eax;" :"=a"(newregs->cs));
 110                asm volatile("movl %%ds, %%eax;" :"=a"(newregs->ds));
 111                asm volatile("movl %%es, %%eax;" :"=a"(newregs->es));
 112                asm volatile("pushfl; popl %0" :"=m"(newregs->flags));
 113#else
 114                asm volatile("movq %%rbx,%0" : "=m"(newregs->bx));
 115                asm volatile("movq %%rcx,%0" : "=m"(newregs->cx));
 116                asm volatile("movq %%rdx,%0" : "=m"(newregs->dx));
 117                asm volatile("movq %%rsi,%0" : "=m"(newregs->si));
 118                asm volatile("movq %%rdi,%0" : "=m"(newregs->di));
 119                asm volatile("movq %%rbp,%0" : "=m"(newregs->bp));
 120                asm volatile("movq %%rax,%0" : "=m"(newregs->ax));
 121                asm volatile("movq %%rsp,%0" : "=m"(newregs->sp));
 122                asm volatile("movq %%r8,%0" : "=m"(newregs->r8));
 123                asm volatile("movq %%r9,%0" : "=m"(newregs->r9));
 124                asm volatile("movq %%r10,%0" : "=m"(newregs->r10));
 125                asm volatile("movq %%r11,%0" : "=m"(newregs->r11));
 126                asm volatile("movq %%r12,%0" : "=m"(newregs->r12));
 127                asm volatile("movq %%r13,%0" : "=m"(newregs->r13));
 128                asm volatile("movq %%r14,%0" : "=m"(newregs->r14));
 129                asm volatile("movq %%r15,%0" : "=m"(newregs->r15));
 130                asm volatile("movl %%ss, %%eax;" :"=a"(newregs->ss));
 131                asm volatile("movl %%cs, %%eax;" :"=a"(newregs->cs));
 132                asm volatile("pushfq; popq %0" :"=m"(newregs->flags));
 133#endif
 134                newregs->ip = (unsigned long)current_text_addr();
 135        }
 136}
 137
 138#ifdef CONFIG_X86_32
 139asmlinkage unsigned long
 140relocate_kernel(unsigned long indirection_page,
 141                unsigned long control_page,
 142                unsigned long start_address,
 143                unsigned int has_pae,
 144                unsigned int preserve_context);
 145#else
 146unsigned long
 147relocate_kernel(unsigned long indirection_page,
 148                unsigned long page_list,
 149                unsigned long start_address,
 150                unsigned int preserve_context);
 151#endif
 152
 153#define ARCH_HAS_KIMAGE_ARCH
 154
 155#ifdef CONFIG_X86_32
 156struct kimage_arch {
 157        pgd_t *pgd;
 158#ifdef CONFIG_X86_PAE
 159        pmd_t *pmd0;
 160        pmd_t *pmd1;
 161#endif
 162        pte_t *pte0;
 163        pte_t *pte1;
 164};
 165#else
 166struct kimage_arch {
 167        pud_t *pud;
 168        pmd_t *pmd;
 169        pte_t *pte;
 170        /* Details of backup region */
 171        unsigned long backup_src_start;
 172        unsigned long backup_src_sz;
 173
 174        /* Physical address of backup segment */
 175        unsigned long backup_load_addr;
 176
 177        /* Core ELF header buffer */
 178        void *elf_headers;
 179        unsigned long elf_headers_sz;
 180        unsigned long elf_load_addr;
 181};
 182#endif /* CONFIG_X86_32 */
 183
 184#ifdef CONFIG_X86_64
 185/*
 186 * Number of elements and order of elements in this structure should match
 187 * with the ones in arch/x86/purgatory/entry64.S. If you make a change here
 188 * make an appropriate change in purgatory too.
 189 */
 190struct kexec_entry64_regs {
 191        uint64_t rax;
 192        uint64_t rcx;
 193        uint64_t rdx;
 194        uint64_t rbx;
 195        uint64_t rsp;
 196        uint64_t rbp;
 197        uint64_t rsi;
 198        uint64_t rdi;
 199        uint64_t r8;
 200        uint64_t r9;
 201        uint64_t r10;
 202        uint64_t r11;
 203        uint64_t r12;
 204        uint64_t r13;
 205        uint64_t r14;
 206        uint64_t r15;
 207        uint64_t rip;
 208};
 209#endif
 210
 211typedef void crash_vmclear_fn(void);
 212extern crash_vmclear_fn __rcu *crash_vmclear_loaded_vmcss;
 213
 214#endif /* __ASSEMBLY__ */
 215
 216#endif /* _ASM_X86_KEXEC_H */
 217