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
  27 /*
  28  * KEXEC_SOURCE_MEMORY_LIMIT maximum page get_free_page can return.
  29  * I.e. Maximum page that is mapped directly into kernel memory,
  30  * and kmap is not required.
  31  *
  32  * So far x86_64 is limited to 40 physical address bits.
  33  */
  34 #ifdef CONFIG_X86_32
  35 /* Maximum physical address we can use pages from */
  36 # define KEXEC_SOURCE_MEMORY_LIMIT (-1UL)
  37 /* Maximum address we can reach in physical address mode */
  38 # define KEXEC_DESTINATION_MEMORY_LIMIT (-1UL)
  39 /* Maximum address we can use for the control code buffer */
  40 # define KEXEC_CONTROL_MEMORY_LIMIT TASK_SIZE
  41
  42 # define KEXEC_CONTROL_PAGE_SIZE        4096
  43
  44 /* The native architecture */
  45 # define KEXEC_ARCH KEXEC_ARCH_386
  46
  47 /* We can also handle crash dumps from 64 bit kernel. */
  48 # define vmcore_elf_check_arch_cross(x) ((x)->e_machine == EM_X86_64)
  49 #else
  50 /* Maximum physical address we can use pages from */
  51 # define KEXEC_SOURCE_MEMORY_LIMIT      (MAXMEM-1)
  52 /* Maximum address we can reach in physical address mode */
  53 # define KEXEC_DESTINATION_MEMORY_LIMIT (MAXMEM-1)
  54 /* Maximum address we can use for the control pages */
  55 # define KEXEC_CONTROL_MEMORY_LIMIT     (MAXMEM-1)
  56
  57 /* Allocate one page for the pdp and the second for the code */
  58 # define KEXEC_CONTROL_PAGE_SIZE  (4096UL + 4096UL)
  59
  60 /* The native architecture */
  61 # define KEXEC_ARCH KEXEC_ARCH_X86_64
  62 #endif
  63
  64 /*
  65  * CPU does not save ss and sp on stack if execution is already
  66  * running in kernel mode at the time of NMI occurrence. This code
  67  * fixes it.
  68  */
  69 static inline void crash_fixup_ss_esp(struct pt_regs *newregs,
  70                                       struct pt_regs *oldregs)
  71 {
  72 #ifdef CONFIG_X86_32
  73         newregs->sp = (unsigned long)&(oldregs->sp);
  74         asm volatile("xorl %%eax, %%eax\n\t"
  75                      "movw %%ss, %%ax\n\t"
  76                      :"=a"(newregs->ss));
  77 #endif
  78 }
  79
  80 /*
  81  * This function is responsible for capturing register states if coming
  82  * via panic otherwise just fix up the ss and sp if coming via kernel
  83  * mode exception.
  84  */
  85 static inline void crash_setup_regs(struct pt_regs *newregs,
  86                                     struct pt_regs *oldregs)
  87 {
  88         if (oldregs) {
  89                 memcpy(newregs, oldregs, sizeof(*newregs));
  90                 crash_fixup_ss_esp(newregs, oldregs);
  91         } else {
  92 #ifdef CONFIG_X86_32
  93                 asm volatile("movl %%ebx,%0" : "=m"(newregs->bx));
  94                 asm volatile("movl %%ecx,%0" : "=m"(newregs->cx));
  95                 asm volatile("movl %%edx,%0" : "=m"(newregs->dx));
  96                 asm volatile("movl %%esi,%0" : "=m"(newregs->si));
  97                 asm volatile("movl %%edi,%0" : "=m"(newregs->di));
  98                 asm volatile("movl %%ebp,%0" : "=m"(newregs->bp));
  99                 asm volatile("movl %%eax,%0" : "=m"(newregs->ax));
 100                 asm volatile("movl %%esp,%0" : "=m"(newregs->sp));
 101                 asm volatile("movl %%ss, %%eax;" :"=a"(newregs->ss));
 102                 asm volatile("movl %%cs, %%eax;" :"=a"(newregs->cs));
 103                 asm volatile("movl %%ds, %%eax;" :"=a"(newregs->ds));
 104                 asm volatile("movl %%es, %%eax;" :"=a"(newregs->es));
 105                 asm volatile("pushfl; popl %0" :"=m"(newregs->flags));
 106 #else
 107                 asm volatile("movq %%rbx,%0" : "=m"(newregs->bx));
 108                 asm volatile("movq %%rcx,%0" : "=m"(newregs->cx));
 109                 asm volatile("movq %%rdx,%0" : "=m"(newregs->dx));
 110                 asm volatile("movq %%rsi,%0" : "=m"(newregs->si));
 111                 asm volatile("movq %%rdi,%0" : "=m"(newregs->di));
 112                 asm volatile("movq %%rbp,%0" : "=m"(newregs->bp));
 113                 asm volatile("movq %%rax,%0" : "=m"(newregs->ax));
 114                 asm volatile("movq %%rsp,%0" : "=m"(newregs->sp));
 115                 asm volatile("movq %%r8,%0" : "=m"(newregs->r8));
 116                 asm volatile("movq %%r9,%0" : "=m"(newregs->r9));
 117                 asm volatile("movq %%r10,%0" : "=m"(newregs->r10));
 118                 asm volatile("movq %%r11,%0" : "=m"(newregs->r11));
 119                 asm volatile("movq %%r12,%0" : "=m"(newregs->r12));
 120                 asm volatile("movq %%r13,%0" : "=m"(newregs->r13));
 121                 asm volatile("movq %%r14,%0" : "=m"(newregs->r14));
 122                 asm volatile("movq %%r15,%0" : "=m"(newregs->r15));
 123                 asm volatile("movl %%ss, %%eax;" :"=a"(newregs->ss));
 124                 asm volatile("movl %%cs, %%eax;" :"=a"(newregs->cs));
 125                 asm volatile("pushfq; popq %0" :"=m"(newregs->flags));
 126 #endif
 127                 newregs->ip = (unsigned long)current_text_addr();
 128         }
 129 }
 130
 131 #ifdef CONFIG_X86_32
 132 asmlinkage unsigned long
 133 relocate_kernel(unsigned long indirection_page,
 134                 unsigned long control_page,
 135                 unsigned long start_address,
 136                 unsigned int has_pae,
 137                 unsigned int preserve_context);
 138 #else
 139 unsigned long
 140 relocate_kernel(unsigned long indirection_page,
 141                 unsigned long page_list,
 142                 unsigned long start_address,
 143                 unsigned int preserve_context);
 144 #endif
 145
 146 #define ARCH_HAS_KIMAGE_ARCH
 147
 148 #ifdef CONFIG_X86_32
 149 struct kimage_arch {
 150         pgd_t *pgd;
 151 #ifdef CONFIG_X86_PAE
 152         pmd_t *pmd0;
 153         pmd_t *pmd1;
 154 #endif
 155         pte_t *pte0;
 156         pte_t *pte1;
 157 };
 158 #else
 159 struct kimage_arch {
 160         pud_t *pud;
 161         pmd_t *pmd;
 162         pte_t *pte;
 163 };
 164 #endif
 165
 166 typedef void crash_vmclear_fn(void);
 167 extern crash_vmclear_fn __rcu *crash_vmclear_loaded_vmcss;
 168
 169 #endif /* __ASSEMBLY__ */
 170
 171 #endif /* _ASM_X86_KEXEC_H */