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 # define PA_SWAP_PAGE           8
  14 # ifdef CONFIG_X86_PAE
  15 #  define PA_PMD_0              9
  16 #  define VA_PMD_0              10
  17 #  define PA_PMD_1              11
  18 #  define VA_PMD_1              12
  19 #  define PAGES_NR              13
  20 # else
  21 #  define PAGES_NR              9
  22 # endif
  23 #else
  24 # define PA_CONTROL_PAGE        0
  25 # define VA_CONTROL_PAGE        1
  26 # define PA_PGD                 2
  27 # define VA_PGD                 3
  28 # define PA_PUD_0               4
  29 # define VA_PUD_0               5
  30 # define PA_PMD_0               6
  31 # define VA_PMD_0               7
  32 # define PA_PTE_0               8
  33 # define VA_PTE_0               9
  34 # define PA_PUD_1               10
  35 # define VA_PUD_1               11
  36 # define PA_PMD_1               12
  37 # define VA_PMD_1               13
  38 # define PA_PTE_1               14
  39 # define VA_PTE_1               15
  40 # define PA_TABLE_PAGE          16
  41 # define PAGES_NR               17
  42 #endif
  43
  44 #ifndef __ASSEMBLY__
  45
  46 #include <linux/string.h>
  47
  48 #include <asm/page.h>
  49 #include <asm/ptrace.h>
  50
  51 /*
  52  * KEXEC_SOURCE_MEMORY_LIMIT maximum page get_free_page can return.
  53  * I.e. Maximum page that is mapped directly into kernel memory,
  54  * and kmap is not required.
  55  *
  56  * So far x86_64 is limited to 40 physical address bits.
  57  */
  58 #ifdef CONFIG_X86_32
  59 /* Maximum physical address we can use pages from */
  60 # define KEXEC_SOURCE_MEMORY_LIMIT (-1UL)
  61 /* Maximum address we can reach in physical address mode */
  62 # define KEXEC_DESTINATION_MEMORY_LIMIT (-1UL)
  63 /* Maximum address we can use for the control code buffer */
  64 # define KEXEC_CONTROL_MEMORY_LIMIT TASK_SIZE
  65
  66 # define KEXEC_CONTROL_CODE_SIZE        4096
  67
  68 /* The native architecture */
  69 # define KEXEC_ARCH KEXEC_ARCH_386
  70
  71 /* We can also handle crash dumps from 64 bit kernel. */
  72 # define vmcore_elf_check_arch_cross(x) ((x)->e_machine == EM_X86_64)
  73 #else
  74 /* Maximum physical address we can use pages from */
  75 # define KEXEC_SOURCE_MEMORY_LIMIT      (0xFFFFFFFFFFUL)
  76 /* Maximum address we can reach in physical address mode */
  77 # define KEXEC_DESTINATION_MEMORY_LIMIT (0xFFFFFFFFFFUL)
  78 /* Maximum address we can use for the control pages */
  79 # define KEXEC_CONTROL_MEMORY_LIMIT     (0xFFFFFFFFFFUL)
  80
  81 /* Allocate one page for the pdp and the second for the code */
  82 # define KEXEC_CONTROL_CODE_SIZE  (4096UL + 4096UL)
  83
  84 /* The native architecture */
  85 # define KEXEC_ARCH KEXEC_ARCH_X86_64
  86 #endif
  87
  88 /*
  89  * CPU does not save ss and sp on stack if execution is already
  90  * running in kernel mode at the time of NMI occurrence. This code
  91  * fixes it.
  92  */
  93 static inline void crash_fixup_ss_esp(struct pt_regs *newregs,
  94                                       struct pt_regs *oldregs)
  95 {
  96 #ifdef CONFIG_X86_32
  97         newregs->sp = (unsigned long)&(oldregs->sp);
  98         asm volatile("xorl %%eax, %%eax\n\t"
  99                      "movw %%ss, %%ax\n\t"
 100                      :"=a"(newregs->ss));
 101 #endif
 102 }
 103
 104 /*
 105  * This function is responsible for capturing register states if coming
 106  * via panic otherwise just fix up the ss and sp if coming via kernel
 107  * mode exception.
 108  */
 109 static inline void crash_setup_regs(struct pt_regs *newregs,
 110                                     struct pt_regs *oldregs)
 111 {
 112         if (oldregs) {
 113                 memcpy(newregs, oldregs, sizeof(*newregs));
 114                 crash_fixup_ss_esp(newregs, oldregs);
 115         } else {
 116 #ifdef CONFIG_X86_32
 117                 asm volatile("movl %%ebx,%0" : "=m"(newregs->bx));
 118                 asm volatile("movl %%ecx,%0" : "=m"(newregs->cx));
 119                 asm volatile("movl %%edx,%0" : "=m"(newregs->dx));
 120                 asm volatile("movl %%esi,%0" : "=m"(newregs->si));
 121                 asm volatile("movl %%edi,%0" : "=m"(newregs->di));
 122                 asm volatile("movl %%ebp,%0" : "=m"(newregs->bp));
 123                 asm volatile("movl %%eax,%0" : "=m"(newregs->ax));
 124                 asm volatile("movl %%esp,%0" : "=m"(newregs->sp));
 125                 asm volatile("movl %%ss, %%eax;" :"=a"(newregs->ss));
 126                 asm volatile("movl %%cs, %%eax;" :"=a"(newregs->cs));
 127                 asm volatile("movl %%ds, %%eax;" :"=a"(newregs->ds));
 128                 asm volatile("movl %%es, %%eax;" :"=a"(newregs->es));
 129                 asm volatile("pushfl; popl %0" :"=m"(newregs->flags));
 130 #else
 131                 asm volatile("movq %%rbx,%0" : "=m"(newregs->bx));
 132                 asm volatile("movq %%rcx,%0" : "=m"(newregs->cx));
 133                 asm volatile("movq %%rdx,%0" : "=m"(newregs->dx));
 134                 asm volatile("movq %%rsi,%0" : "=m"(newregs->si));
 135                 asm volatile("movq %%rdi,%0" : "=m"(newregs->di));
 136                 asm volatile("movq %%rbp,%0" : "=m"(newregs->bp));
 137                 asm volatile("movq %%rax,%0" : "=m"(newregs->ax));
 138                 asm volatile("movq %%rsp,%0" : "=m"(newregs->sp));
 139                 asm volatile("movq %%r8,%0" : "=m"(newregs->r8));
 140                 asm volatile("movq %%r9,%0" : "=m"(newregs->r9));
 141                 asm volatile("movq %%r10,%0" : "=m"(newregs->r10));
 142                 asm volatile("movq %%r11,%0" : "=m"(newregs->r11));
 143                 asm volatile("movq %%r12,%0" : "=m"(newregs->r12));
 144                 asm volatile("movq %%r13,%0" : "=m"(newregs->r13));
 145                 asm volatile("movq %%r14,%0" : "=m"(newregs->r14));
 146                 asm volatile("movq %%r15,%0" : "=m"(newregs->r15));
 147                 asm volatile("movl %%ss, %%eax;" :"=a"(newregs->ss));
 148                 asm volatile("movl %%cs, %%eax;" :"=a"(newregs->cs));
 149                 asm volatile("pushfq; popq %0" :"=m"(newregs->flags));
 150 #endif
 151                 newregs->ip = (unsigned long)current_text_addr();
 152         }
 153 }
 154
 155 #ifdef CONFIG_X86_32
 156 asmlinkage unsigned long
 157 relocate_kernel(unsigned long indirection_page,
 158                 unsigned long control_page,
 159                 unsigned long start_address,
 160                 unsigned int has_pae,
 161                 unsigned int preserve_context);
 162 #else
 163 NORET_TYPE void
 164 relocate_kernel(unsigned long indirection_page,
 165                 unsigned long page_list,
 166                 unsigned long start_address) ATTRIB_NORET;
 167 #endif
 168
 169 #endif /* __ASSEMBLY__ */
 170
 171 #endif /* _KEXEC_H */