include/asm-x86/kexec.h

   1 #ifndef _KEXEC_H
   2 #define _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 VA_PGD                 3
   9 # define PA_PTE_0               4
  10 # define VA_PTE_0               5
  11 # define PA_PTE_1               6
  12 # define VA_PTE_1               7
  13 # ifdef CONFIG_X86_PAE
  14 #  define PA_PMD_0              8
  15 #  define VA_PMD_0              9
  16 #  define PA_PMD_1              10
  17 #  define VA_PMD_1              11
  18 #  define PAGES_NR              12
  19 # else
  20 #  define PAGES_NR              8
  21 # endif
  22 #else
  23 # define PA_CONTROL_PAGE        0
  24 # define VA_CONTROL_PAGE        1
  25 # define PA_PGD                 2
  26 # define VA_PGD                 3
  27 # define PA_PUD_0               4
  28 # define VA_PUD_0               5
  29 # define PA_PMD_0               6
  30 # define VA_PMD_0               7
  31 # define PA_PTE_0               8
  32 # define VA_PTE_0               9
  33 # define PA_PUD_1               10
  34 # define VA_PUD_1               11
  35 # define PA_PMD_1               12
  36 # define VA_PMD_1               13
  37 # define PA_PTE_1               14
  38 # define VA_PTE_1               15
  39 # define PA_TABLE_PAGE          16
  40 # define PAGES_NR               17
  41 #endif
  42
  43 #ifndef __ASSEMBLY__
  44
  45 #include <linux/string.h>
  46
  47 #include <asm/page.h>
  48 #include <asm/ptrace.h>
  49
  50 /*
  51  * KEXEC_SOURCE_MEMORY_LIMIT maximum page get_free_page can return.
  52  * I.e. Maximum page that is mapped directly into kernel memory,
  53  * and kmap is not required.
  54  *
  55  * So far x86_64 is limited to 40 physical address bits.
  56  */
  57 #ifdef CONFIG_X86_32
  58 /* Maximum physical address we can use pages from */
  59 # define KEXEC_SOURCE_MEMORY_LIMIT (-1UL)
  60 /* Maximum address we can reach in physical address mode */
  61 # define KEXEC_DESTINATION_MEMORY_LIMIT (-1UL)
  62 /* Maximum address we can use for the control code buffer */
  63 # define KEXEC_CONTROL_MEMORY_LIMIT TASK_SIZE
  64
  65 # define KEXEC_CONTROL_CODE_SIZE        4096
  66
  67 /* The native architecture */
  68 # define KEXEC_ARCH KEXEC_ARCH_386
  69
  70 /* We can also handle crash dumps from 64 bit kernel. */
  71 # define vmcore_elf_check_arch_cross(x) ((x)->e_machine == EM_X86_64)
  72 #else
  73 /* Maximum physical address we can use pages from */
  74 # define KEXEC_SOURCE_MEMORY_LIMIT      (0xFFFFFFFFFFUL)
  75 /* Maximum address we can reach in physical address mode */
  76 # define KEXEC_DESTINATION_MEMORY_LIMIT (0xFFFFFFFFFFUL)
  77 /* Maximum address we can use for the control pages */
  78 # define KEXEC_CONTROL_MEMORY_LIMIT     (0xFFFFFFFFFFUL)
  79
  80 /* Allocate one page for the pdp and the second for the code */
  81 # define KEXEC_CONTROL_CODE_SIZE  (4096UL + 4096UL)
  82
  83 /* The native architecture */
  84 # define KEXEC_ARCH KEXEC_ARCH_X86_64
  85 #endif
  86
  87 /*
  88  * CPU does not save ss and sp on stack if execution is already
  89  * running in kernel mode at the time of NMI occurrence. This code
  90  * fixes it.
  91  */
  92 static inline void crash_fixup_ss_esp(struct pt_regs *newregs,
  93                                       struct pt_regs *oldregs)
  94 {
  95 #ifdef CONFIG_X86_32
  96         newregs->sp = (unsigned long)&(oldregs->sp);
  97         asm volatile("xorl %%eax, %%eax\n\t"
  98                      "movw %%ss, %%ax\n\t"
  99                      :"=a"(newregs->ss));
 100 #endif
 101 }
 102
 103 /*
 104  * This function is responsible for capturing register states if coming
 105  * via panic otherwise just fix up the ss and sp if coming via kernel
 106  * mode exception.
 107  */
 108 static inline void crash_setup_regs(struct pt_regs *newregs,
 109                                     struct pt_regs *oldregs)
 110 {
 111         if (oldregs) {
 112                 memcpy(newregs, oldregs, sizeof(*newregs));
 113                 crash_fixup_ss_esp(newregs, oldregs);
 114         } else {
 115 #ifdef CONFIG_X86_32
 116                 asm volatile("movl %%ebx,%0" : "=m"(newregs->bx));
 117                 asm volatile("movl %%ecx,%0" : "=m"(newregs->cx));
 118                 asm volatile("movl %%edx,%0" : "=m"(newregs->dx));
 119                 asm volatile("movl %%esi,%0" : "=m"(newregs->si));
 120                 asm volatile("movl %%edi,%0" : "=m"(newregs->di));
 121                 asm volatile("movl %%ebp,%0" : "=m"(newregs->bp));
 122                 asm volatile("movl %%eax,%0" : "=m"(newregs->ax));
 123                 asm volatile("movl %%esp,%0" : "=m"(newregs->sp));
 124                 asm volatile("movl %%ss, %%eax;" :"=a"(newregs->ss));
 125                 asm volatile("movl %%cs, %%eax;" :"=a"(newregs->cs));
 126                 asm volatile("movl %%ds, %%eax;" :"=a"(newregs->ds));
 127                 asm volatile("movl %%es, %%eax;" :"=a"(newregs->es));
 128                 asm volatile("pushfl; popl %0" :"=m"(newregs->flags));
 129 #else
 130                 asm volatile("movq %%rbx,%0" : "=m"(newregs->bx));
 131                 asm volatile("movq %%rcx,%0" : "=m"(newregs->cx));
 132                 asm volatile("movq %%rdx,%0" : "=m"(newregs->dx));
 133                 asm volatile("movq %%rsi,%0" : "=m"(newregs->si));
 134                 asm volatile("movq %%rdi,%0" : "=m"(newregs->di));
 135                 asm volatile("movq %%rbp,%0" : "=m"(newregs->bp));
 136                 asm volatile("movq %%rax,%0" : "=m"(newregs->ax));
 137                 asm volatile("movq %%rsp,%0" : "=m"(newregs->sp));
 138                 asm volatile("movq %%r8,%0" : "=m"(newregs->r8));
 139                 asm volatile("movq %%r9,%0" : "=m"(newregs->r9));
 140                 asm volatile("movq %%r10,%0" : "=m"(newregs->r10));
 141                 asm volatile("movq %%r11,%0" : "=m"(newregs->r11));
 142                 asm volatile("movq %%r12,%0" : "=m"(newregs->r12));
 143                 asm volatile("movq %%r13,%0" : "=m"(newregs->r13));
 144                 asm volatile("movq %%r14,%0" : "=m"(newregs->r14));
 145                 asm volatile("movq %%r15,%0" : "=m"(newregs->r15));
 146                 asm volatile("movl %%ss, %%eax;" :"=a"(newregs->ss));
 147                 asm volatile("movl %%cs, %%eax;" :"=a"(newregs->cs));
 148                 asm volatile("pushfq; popq %0" :"=m"(newregs->flags));
 149 #endif
 150                 newregs->ip = (unsigned long)current_text_addr();
 151         }
 152 }
 153
 154 #ifdef CONFIG_X86_32
 155 asmlinkage NORET_TYPE void
 156 relocate_kernel(unsigned long indirection_page,
 157                 unsigned long control_page,
 158                 unsigned long start_address,
 159                 unsigned int has_pae) ATTRIB_NORET;
 160 #else
 161 NORET_TYPE void
 162 relocate_kernel(unsigned long indirection_page,
 163                 unsigned long page_list,
 164                 unsigned long start_address) ATTRIB_NORET;
 165 #endif
 166
 167 #endif /* __ASSEMBLY__ */
 168
 169 #endif /* _KEXEC_H */