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 #ifdef CONFIG_X86_32
  45 # define KEXEC_CONTROL_CODE_MAX_SIZE    2048
  46 #endif
  47
  48 #ifndef __ASSEMBLY__
  49
  50 #include <linux/string.h>
  51
  52 #include <asm/page.h>
  53 #include <asm/ptrace.h>
  54
  55 /*
  56  * KEXEC_SOURCE_MEMORY_LIMIT maximum page get_free_page can return.
  57  * I.e. Maximum page that is mapped directly into kernel memory,
  58  * and kmap is not required.
  59  *
  60  * So far x86_64 is limited to 40 physical address bits.
  61  */
  62 #ifdef CONFIG_X86_32
  63 /* Maximum physical address we can use pages from */
  64 # define KEXEC_SOURCE_MEMORY_LIMIT (-1UL)
  65 /* Maximum address we can reach in physical address mode */
  66 # define KEXEC_DESTINATION_MEMORY_LIMIT (-1UL)
  67 /* Maximum address we can use for the control code buffer */
  68 # define KEXEC_CONTROL_MEMORY_LIMIT TASK_SIZE
  69
  70 # define KEXEC_CONTROL_PAGE_SIZE        4096
  71
  72 /* The native architecture */
  73 # define KEXEC_ARCH KEXEC_ARCH_386
  74
  75 /* We can also handle crash dumps from 64 bit kernel. */
  76 # define vmcore_elf_check_arch_cross(x) ((x)->e_machine == EM_X86_64)
  77 #else
  78 /* Maximum physical address we can use pages from */
  79 # define KEXEC_SOURCE_MEMORY_LIMIT      (0xFFFFFFFFFFUL)
  80 /* Maximum address we can reach in physical address mode */
  81 # define KEXEC_DESTINATION_MEMORY_LIMIT (0xFFFFFFFFFFUL)
  82 /* Maximum address we can use for the control pages */
  83 # define KEXEC_CONTROL_MEMORY_LIMIT     (0xFFFFFFFFFFUL)
  84
  85 /* Allocate one page for the pdp and the second for the code */
  86 # define KEXEC_CONTROL_PAGE_SIZE  (4096UL + 4096UL)
  87
  88 /* The native architecture */
  89 # define KEXEC_ARCH KEXEC_ARCH_X86_64
  90 #endif
  91
  92 /*
  93  * CPU does not save ss and sp on stack if execution is already
  94  * running in kernel mode at the time of NMI occurrence. This code
  95  * fixes it.
  96  */
  97 static inline void crash_fixup_ss_esp(struct pt_regs *newregs,
  98                                       struct pt_regs *oldregs)
  99 {
 100 #ifdef CONFIG_X86_32
 101         newregs->sp = (unsigned long)&(oldregs->sp);
 102         asm volatile("xorl %%eax, %%eax\n\t"
 103                      "movw %%ss, %%ax\n\t"
 104                      :"=a"(newregs->ss));
 105 #endif
 106 }
 107
 108 /*
 109  * This function is responsible for capturing register states if coming
 110  * via panic otherwise just fix up the ss and sp if coming via kernel
 111  * mode exception.
 112  */
 113 static inline void crash_setup_regs(struct pt_regs *newregs,
 114                                     struct pt_regs *oldregs)
 115 {
 116         if (oldregs) {
 117                 memcpy(newregs, oldregs, sizeof(*newregs));
 118                 crash_fixup_ss_esp(newregs, oldregs);
 119         } else {
 120 #ifdef CONFIG_X86_32
 121                 asm volatile("movl %%ebx,%0" : "=m"(newregs->bx));
 122                 asm volatile("movl %%ecx,%0" : "=m"(newregs->cx));
 123                 asm volatile("movl %%edx,%0" : "=m"(newregs->dx));
 124                 asm volatile("movl %%esi,%0" : "=m"(newregs->si));
 125                 asm volatile("movl %%edi,%0" : "=m"(newregs->di));
 126                 asm volatile("movl %%ebp,%0" : "=m"(newregs->bp));
 127                 asm volatile("movl %%eax,%0" : "=m"(newregs->ax));
 128                 asm volatile("movl %%esp,%0" : "=m"(newregs->sp));
 129                 asm volatile("movl %%ss, %%eax;" :"=a"(newregs->ss));
 130                 asm volatile("movl %%cs, %%eax;" :"=a"(newregs->cs));
 131                 asm volatile("movl %%ds, %%eax;" :"=a"(newregs->ds));
 132                 asm volatile("movl %%es, %%eax;" :"=a"(newregs->es));
 133                 asm volatile("pushfl; popl %0" :"=m"(newregs->flags));
 134 #else
 135                 asm volatile("movq %%rbx,%0" : "=m"(newregs->bx));
 136                 asm volatile("movq %%rcx,%0" : "=m"(newregs->cx));
 137                 asm volatile("movq %%rdx,%0" : "=m"(newregs->dx));
 138                 asm volatile("movq %%rsi,%0" : "=m"(newregs->si));
 139                 asm volatile("movq %%rdi,%0" : "=m"(newregs->di));
 140                 asm volatile("movq %%rbp,%0" : "=m"(newregs->bp));
 141                 asm volatile("movq %%rax,%0" : "=m"(newregs->ax));
 142                 asm volatile("movq %%rsp,%0" : "=m"(newregs->sp));
 143                 asm volatile("movq %%r8,%0" : "=m"(newregs->r8));
 144                 asm volatile("movq %%r9,%0" : "=m"(newregs->r9));
 145                 asm volatile("movq %%r10,%0" : "=m"(newregs->r10));
 146                 asm volatile("movq %%r11,%0" : "=m"(newregs->r11));
 147                 asm volatile("movq %%r12,%0" : "=m"(newregs->r12));
 148                 asm volatile("movq %%r13,%0" : "=m"(newregs->r13));
 149                 asm volatile("movq %%r14,%0" : "=m"(newregs->r14));
 150                 asm volatile("movq %%r15,%0" : "=m"(newregs->r15));
 151                 asm volatile("movl %%ss, %%eax;" :"=a"(newregs->ss));
 152                 asm volatile("movl %%cs, %%eax;" :"=a"(newregs->cs));
 153                 asm volatile("pushfq; popq %0" :"=m"(newregs->flags));
 154 #endif
 155                 newregs->ip = (unsigned long)current_text_addr();
 156         }
 157 }
 158
 159 #ifdef CONFIG_X86_32
 160 asmlinkage unsigned long
 161 relocate_kernel(unsigned long indirection_page,
 162                 unsigned long control_page,
 163                 unsigned long start_address,
 164                 unsigned int has_pae,
 165                 unsigned int preserve_context);
 166 #else
 167 NORET_TYPE void
 168 relocate_kernel(unsigned long indirection_page,
 169                 unsigned long page_list,
 170                 unsigned long start_address) ATTRIB_NORET;
 171 #endif
 172
 173 #endif /* __ASSEMBLY__ */
 174
 175 #endif /* _KEXEC_H */