sigcontext.h

Go to the documentation of this file.

#ifndef _ASM_IA64_SIGCONTEXT_H
#define _ASM_IA64_SIGCONTEXT_H

/*
 * Copyright (C) 1998, 1999, 2001 Hewlett-Packard Co
 * Copyright (C) 1998, 1999, 2001 David Mosberger-Tang <[email protected]>
 */

#include <asm/fpu.h>

#define IA64_SC_FLAG_ONSTACK_BIT        0   /* is handler running on signal stack? */
#define IA64_SC_FLAG_IN_SYSCALL_BIT     1   /* did signal interrupt a syscall? */
#define IA64_SC_FLAG_FPH_VALID_BIT      2   /* is state in f[32]-f[127] valid? */

#define IA64_SC_FLAG_ONSTACK        (1 << IA64_SC_FLAG_ONSTACK_BIT)
#define IA64_SC_FLAG_IN_SYSCALL     (1 << IA64_SC_FLAG_IN_SYSCALL_BIT)
#define IA64_SC_FLAG_FPH_VALID      (1 << IA64_SC_FLAG_FPH_VALID_BIT)

# ifndef __ASSEMBLY__

/*
 * Note on handling of register backing store: sc_ar_bsp contains the address that would
 * be found in ar.bsp after executing a "cover" instruction the context in which the
 * signal was raised.  If signal delivery required switching to an alternate signal stack
 * (sc_rbs_base is not NULL), the "dirty" partition (as it would exist after executing the
 * imaginary "cover" instruction) is backed by the *alternate* signal stack, not the
 * original one.  In this case, sc_rbs_base contains the base address of the new register
 * backing store.  The number of registers in the dirty partition can be calculated as:
 *
 *   ndirty = ia64_rse_num_regs(sc_rbs_base, sc_rbs_base + (sc_loadrs >> 16))
 *
 */

struct sigcontext {
    unsigned long       sc_flags;   /* see manifest constants above */
    unsigned long       sc_nat;     /* bit i == 1 iff scratch reg gr[i] is a NaT */
    stack_t         sc_stack;   /* previously active stack */

    unsigned long       sc_ip;      /* instruction pointer */
    unsigned long       sc_cfm;     /* current frame marker */
    unsigned long       sc_um;      /* user mask bits */
    unsigned long       sc_ar_rsc;  /* register stack configuration register */
    unsigned long       sc_ar_bsp;  /* backing store pointer */
    unsigned long       sc_ar_rnat; /* RSE NaT collection register */
    unsigned long       sc_ar_ccv;  /* compare and exchange compare value register */
    unsigned long       sc_ar_unat; /* ar.unat of interrupted context */
    unsigned long       sc_ar_fpsr; /* floating-point status register */
    unsigned long       sc_ar_pfs;  /* previous function state */
    unsigned long       sc_ar_lc;   /* loop count register */
    unsigned long       sc_pr;      /* predicate registers */
    unsigned long       sc_br[8];   /* branch registers */
    /* Note: sc_gr[0] is used as the "uc_link" member of ucontext_t */
    unsigned long       sc_gr[32];  /* general registers (static partition) */
    struct ia64_fpreg   sc_fr[128]; /* floating-point registers */

    unsigned long       sc_rbs_base;    /* NULL or new base of sighandler's rbs */
    unsigned long       sc_loadrs;  /* see description above */

    unsigned long       sc_ar25;    /* cmp8xchg16 uses this */
    unsigned long       sc_ar26;    /* rsvd for scratch use */
    unsigned long       sc_rsvd[12];    /* reserved for future use */
    /*
     * The mask must come last so we can increase _NSIG_WORDS
     * without breaking binary compatibility.
     */
    sigset_t        sc_mask;    /* signal mask to restore after handler returns */
};

# endif /* __ASSEMBLY__ */
#endif /* _ASM_IA64_SIGCONTEXT_H */