中断现场保存数据结构

/*
 * This struct defines the way the registers are stored on the stack during an
 * exception. Note that sizeof(struct pt_regs) has to be a multiple of 16 (for
 * stack alignment). struct user_pt_regs must form a prefix of struct pt_regs.
 */
struct pt_regs {
    union {
        struct user_pt_regs user_regs;
        struct {
            u64 regs[31];
            u64 sp;
            u64 pc;
            u64 pstate;
        };
    };
    u64 orig_x0;
#ifdef __AARCH64EB__
    u32 unused2;
    s32 syscallno;
#else
    s32 syscallno;
    u32 unused2;
#endif
    u64 sdei_ttbr1;
    /* Only valid when ARM64_HAS_IRQ_PRIO_MASKING is enabled. */
    u64 pmr_save;
    u64 stackframe[2];

    /* Only valid for some EL1 exceptions. */
    u64 lockdep_hardirqs;
    u64 exit_rcu;
};

#endif
  BLANK();
  DEFINE(S_X0,			offsetof(struct pt_regs, regs[0]));
  DEFINE(S_X2,			offsetof(struct pt_regs, regs[2]));
  DEFINE(S_X4,			offsetof(struct pt_regs, regs[4]));
  DEFINE(S_X6,			offsetof(struct pt_regs, regs[6]));
  DEFINE(S_X8,			offsetof(struct pt_regs, regs[8]));
  DEFINE(S_X10,			offsetof(struct pt_regs, regs[10]));
  DEFINE(S_X12,			offsetof(struct pt_regs, regs[12]));
  DEFINE(S_X14,			offsetof(struct pt_regs, regs[14]));
  DEFINE(S_X16,			offsetof(struct pt_regs, regs[16]));
  DEFINE(S_X18,			offsetof(struct pt_regs, regs[18]));
  DEFINE(S_X20,			offsetof(struct pt_regs, regs[20]));
  DEFINE(S_X22,			offsetof(struct pt_regs, regs[22]));
  DEFINE(S_X24,			offsetof(struct pt_regs, regs[24]));
  DEFINE(S_X26,			offsetof(struct pt_regs, regs[26]));
  DEFINE(S_X28,			offsetof(struct pt_regs, regs[28]));
  DEFINE(S_FP,			offsetof(struct pt_regs, regs[29]));
  DEFINE(S_LR,			offsetof(struct pt_regs, regs[30]));
  DEFINE(S_SP,			offsetof(struct pt_regs, sp));
  DEFINE(S_PSTATE,		offsetof(struct pt_regs, pstate));
  DEFINE(S_PC,			offsetof(struct pt_regs, pc));
  DEFINE(S_SYSCALLNO,		offsetof(struct pt_regs, syscallno));
  DEFINE(S_SDEI_TTBR1,		offsetof(struct pt_regs, sdei_ttbr1));
  DEFINE(S_PMR_SAVE,		offsetof(struct pt_regs, pmr_save));
  DEFINE(S_STACKFRAME,		offsetof(struct pt_regs, stackframe));
  DEFINE(PT_REGS_SIZE,		sizeof(struct pt_regs));
  BLANK();
#ifdef CONFIG_COMPAT