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 #include <asm/bootparam.h>
  27
  28 struct kimage;
  29
  30 /*
  31  * KEXEC_SOURCE_MEMORY_LIMIT maximum page get_free_page can return.
  32  * I.e. Maximum page that is mapped directly into kernel memory,
  33  * and kmap is not required.
  34  *
  35  * So far x86_64 is limited to 40 physical address bits.
  36  */
  37 #ifdef CONFIG_X86_32
  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_PAGE_SIZE        4096
  46
  47 /* The native architecture */
  48 # define KEXEC_ARCH KEXEC_ARCH_386
  49
  50 /* We can also handle crash dumps from 64 bit kernel. */
  51 # define vmcore_elf_check_arch_cross(x) ((x)->e_machine == EM_X86_64)
  52 #else
  53 /* Maximum physical address we can use pages from */
  54 # define KEXEC_SOURCE_MEMORY_LIMIT      (MAXMEM-1)
  55 /* Maximum address we can reach in physical address mode */
  56 # define KEXEC_DESTINATION_MEMORY_LIMIT (MAXMEM-1)
  57 /* Maximum address we can use for the control pages */
  58 # define KEXEC_CONTROL_MEMORY_LIMIT     (MAXMEM-1)
  59
  60 /* Allocate one page for the pdp and the second for the code */
  61 # define KEXEC_CONTROL_PAGE_SIZE  (4096UL + 4096UL)
  62
  63 /* The native architecture */
  64 # define KEXEC_ARCH KEXEC_ARCH_X86_64
  65 #endif
  66
  67 /* Memory to backup during crash kdump */
  68 #define KEXEC_BACKUP_SRC_START  (0UL)
  69 #define KEXEC_BACKUP_SRC_END    (640 * 1024UL)  /* 640K */
  70
  71 /*
  72  * CPU does not save ss and sp on stack if execution is already
  73  * running in kernel mode at the time of NMI occurrence. This code
  74  * fixes it.
  75  */
  76 static inline void crash_fixup_ss_esp(struct pt_regs *newregs,
  77                                       struct pt_regs *oldregs)
  78 {
  79 #ifdef CONFIG_X86_32
  80         newregs->sp = (unsigned long)&(oldregs->sp);
  81         asm volatile("xorl %%eax, %%eax\n\t"
  82                      "movw %%ss, %%ax\n\t"
  83                      :"=a"(newregs->ss));
  84 #endif
  85 }
  86
  87 /*
  88  * This function is responsible for capturing register states if coming
  89  * via panic otherwise just fix up the ss and sp if coming via kernel
  90  * mode exception.
  91  */
  92 static inline void crash_setup_regs(struct pt_regs *newregs,
  93                                     struct pt_regs *oldregs)
  94 {
  95         if (oldregs) {
  96                 memcpy(newregs, oldregs, sizeof(*newregs));
  97                 crash_fixup_ss_esp(newregs, oldregs);
  98         } else {
  99 #ifdef CONFIG_X86_32
 100                 asm volatile("movl %%ebx,%0" : "=m"(newregs->bx));
 101                 asm volatile("movl %%ecx,%0" : "=m"(newregs->cx));
 102                 asm volatile("movl %%edx,%0" : "=m"(newregs->dx));
 103                 asm volatile("movl %%esi,%0" : "=m"(newregs->si));
 104                 asm volatile("movl %%edi,%0" : "=m"(newregs->di));
 105                 asm volatile("movl %%ebp,%0" : "=m"(newregs->bp));
 106                 asm volatile("movl %%eax,%0" : "=m"(newregs->ax));
 107                 asm volatile("movl %%esp,%0" : "=m"(newregs->sp));
 108                 asm volatile("movl %%ss, %%eax;" :"=a"(newregs->ss));
 109                 asm volatile("movl %%cs, %%eax;" :"=a"(newregs->cs));
 110                 asm volatile("movl %%ds, %%eax;" :"=a"(newregs->ds));
 111                 asm volatile("movl %%es, %%eax;" :"=a"(newregs->es));
 112                 asm volatile("pushfl; popl %0" :"=m"(newregs->flags));
 113 #else
 114                 asm volatile("movq %%rbx,%0" : "=m"(newregs->bx));
 115                 asm volatile("movq %%rcx,%0" : "=m"(newregs->cx));
 116                 asm volatile("movq %%rdx,%0" : "=m"(newregs->dx));
 117                 asm volatile("movq %%rsi,%0" : "=m"(newregs->si));
 118                 asm volatile("movq %%rdi,%0" : "=m"(newregs->di));
 119                 asm volatile("movq %%rbp,%0" : "=m"(newregs->bp));
 120                 asm volatile("movq %%rax,%0" : "=m"(newregs->ax));
 121                 asm volatile("movq %%rsp,%0" : "=m"(newregs->sp));
 122                 asm volatile("movq %%r8,%0" : "=m"(newregs->r8));
 123                 asm volatile("movq %%r9,%0" : "=m"(newregs->r9));
 124                 asm volatile("movq %%r10,%0" : "=m"(newregs->r10));
 125                 asm volatile("movq %%r11,%0" : "=m"(newregs->r11));
 126                 asm volatile("movq %%r12,%0" : "=m"(newregs->r12));
 127                 asm volatile("movq %%r13,%0" : "=m"(newregs->r13));
 128                 asm volatile("movq %%r14,%0" : "=m"(newregs->r14));
 129                 asm volatile("movq %%r15,%0" : "=m"(newregs->r15));
 130                 asm volatile("movl %%ss, %%eax;" :"=a"(newregs->ss));
 131                 asm volatile("movl %%cs, %%eax;" :"=a"(newregs->cs));
 132                 asm volatile("pushfq; popq %0" :"=m"(newregs->flags));
 133 #endif
 134                 newregs->ip = (unsigned long)current_text_addr();
 135         }
 136 }
 137
 138 #ifdef CONFIG_X86_32
 139 asmlinkage unsigned long
 140 relocate_kernel(unsigned long indirection_page,
 141                 unsigned long control_page,
 142                 unsigned long start_address,
 143                 unsigned int has_pae,
 144                 unsigned int preserve_context);
 145 #else
 146 unsigned long
 147 relocate_kernel(unsigned long indirection_page,
 148                 unsigned long page_list,
 149                 unsigned long start_address,
 150                 unsigned int preserve_context);
 151 #endif
 152
 153 #define ARCH_HAS_KIMAGE_ARCH
 154
 155 #ifdef CONFIG_X86_32
 156 struct kimage_arch {
 157         pgd_t *pgd;
 158 #ifdef CONFIG_X86_PAE
 159         pmd_t *pmd0;
 160         pmd_t *pmd1;
 161 #endif
 162         pte_t *pte0;
 163         pte_t *pte1;
 164 };
 165 #else
 166 struct kimage_arch {
 167         pud_t *pud;
 168         pmd_t *pmd;
 169         pte_t *pte;
 170         /* Details of backup region */
 171         unsigned long backup_src_start;
 172         unsigned long backup_src_sz;
 173
 174         /* Physical address of backup segment */
 175         unsigned long backup_load_addr;
 176
 177         /* Core ELF header buffer */
 178         void *elf_headers;
 179         unsigned long elf_headers_sz;
 180         unsigned long elf_load_addr;
 181 };
 182 #endif /* CONFIG_X86_32 */
 183
 184 #ifdef CONFIG_X86_64
 185 /*
 186  * Number of elements and order of elements in this structure should match
 187  * with the ones in arch/x86/purgatory/entry64.S. If you make a change here
 188  * make an appropriate change in purgatory too.
 189  */
 190 struct kexec_entry64_regs {
 191         uint64_t rax;
 192         uint64_t rcx;
 193         uint64_t rdx;
 194         uint64_t rbx;
 195         uint64_t rsp;
 196         uint64_t rbp;
 197         uint64_t rsi;
 198         uint64_t rdi;
 199         uint64_t r8;
 200         uint64_t r9;
 201         uint64_t r10;
 202         uint64_t r11;
 203         uint64_t r12;
 204         uint64_t r13;
 205         uint64_t r14;
 206         uint64_t r15;
 207         uint64_t rip;
 208 };
 209 #endif
 210
 211 typedef void crash_vmclear_fn(void);
 212 extern crash_vmclear_fn __rcu *crash_vmclear_loaded_vmcss;
 213
 214 #endif /* __ASSEMBLY__ */
 215
 216 #endif /* _ASM_X86_KEXEC_H */