include/asm-i386/kexec.h

   1 #ifndef _I386_KEXEC_H
   2 #define _I386_KEXEC_H
   3
   4 #define PA_CONTROL_PAGE  0
   5 #define VA_CONTROL_PAGE  1
   6 #define PA_PGD           2
   7 #define VA_PGD           3
   8 #define PA_PTE_0         4
   9 #define VA_PTE_0         5
  10 #define PA_PTE_1         6
  11 #define VA_PTE_1         7
  12 #ifdef CONFIG_X86_PAE
  13 #define PA_PMD_0         8
  14 #define VA_PMD_0         9
  15 #define PA_PMD_1         10
  16 #define VA_PMD_1         11
  17 #define PAGES_NR         12
  18 #else
  19 #define PAGES_NR         8
  20 #endif
  21
  22 #ifndef __ASSEMBLY__
  23
  24 #include <asm/fixmap.h>
  25 #include <asm/ptrace.h>
  26 #include <asm/string.h>
  27
  28 /*
  29  * KEXEC_SOURCE_MEMORY_LIMIT maximum page get_free_page can return.
  30  * I.e. Maximum page that is mapped directly into kernel memory,
  31  * and kmap is not required.
  32  *
  33  * Someone correct me if FIXADDR_START - PAGEOFFSET is not the correct
  34  * calculation for the amount of memory directly mappable into the
  35  * kernel memory space.
  36  */
  37
  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_CODE_SIZE 4096
  46
  47 /* The native architecture */
  48 #define KEXEC_ARCH KEXEC_ARCH_386
  49
  50 #define MAX_NOTE_BYTES 1024
  51
  52 /* CPU does not save ss and esp on stack if execution is already
  53  * running in kernel mode at the time of NMI occurrence. This code
  54  * fixes it.
  55  */
  56 static inline void crash_fixup_ss_esp(struct pt_regs *newregs,
  57                                         struct pt_regs *oldregs)
  58 {
  59         memcpy(newregs, oldregs, sizeof(*newregs));
  60         newregs->esp = (unsigned long)&(oldregs->esp);
  61         __asm__ __volatile__(
  62                         "xorl %%eax, %%eax\n\t"
  63                         "movw %%ss, %%ax\n\t"
  64                         :"=a"(newregs->xss));
  65 }
  66
  67 /*
  68  * This function is responsible for capturing register states if coming
  69  * via panic otherwise just fix up the ss and esp if coming via kernel
  70  * mode exception.
  71  */
  72 static inline void crash_setup_regs(struct pt_regs *newregs,
  73                                        struct pt_regs *oldregs)
  74 {
  75        if (oldregs)
  76                crash_fixup_ss_esp(newregs, oldregs);
  77        else {
  78                __asm__ __volatile__("movl %%ebx,%0" : "=m"(newregs->ebx));
  79                __asm__ __volatile__("movl %%ecx,%0" : "=m"(newregs->ecx));
  80                __asm__ __volatile__("movl %%edx,%0" : "=m"(newregs->edx));
  81                __asm__ __volatile__("movl %%esi,%0" : "=m"(newregs->esi));
  82                __asm__ __volatile__("movl %%edi,%0" : "=m"(newregs->edi));
  83                __asm__ __volatile__("movl %%ebp,%0" : "=m"(newregs->ebp));
  84                __asm__ __volatile__("movl %%eax,%0" : "=m"(newregs->eax));
  85                __asm__ __volatile__("movl %%esp,%0" : "=m"(newregs->esp));
  86                __asm__ __volatile__("movw %%ss, %%ax;" :"=a"(newregs->xss));
  87                __asm__ __volatile__("movw %%cs, %%ax;" :"=a"(newregs->xcs));
  88                __asm__ __volatile__("movw %%ds, %%ax;" :"=a"(newregs->xds));
  89                __asm__ __volatile__("movw %%es, %%ax;" :"=a"(newregs->xes));
  90                __asm__ __volatile__("pushfl; popl %0" :"=m"(newregs->eflags));
  91
  92                newregs->eip = (unsigned long)current_text_addr();
  93        }
  94 }
  95 asmlinkage NORET_TYPE void
  96 relocate_kernel(unsigned long indirection_page,
  97                 unsigned long control_page,
  98                 unsigned long start_address,
  99                 unsigned int has_pae) ATTRIB_NORET;
 100
 101 #endif /* __ASSEMBLY__ */
 102
 103 #endif /* _I386_KEXEC_H */