/* Copyright (C) 1998, 1999, 2002, 2004, 2005 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
. */
#ifndef _SYS_UCONTEXT_H
#define _SYS_UCONTEXT_H 1
#include
#include
/* We need the signal context definitions even if they are not used
included in . */
#include
#if __WORDSIZE == 32
/* Number of general registers. */
# define NGREG 48
/* Container for all general registers. */
typedef unsigned long gregset_t[NGREG];
/* Container for floating-point registers and status */
typedef struct _libc_fpstate
{
double fpregs[32];
double fpscr;
unsigned int _pad[2];
} fpregset_t;
/* Container for Altivec/VMX registers and status.
Needs to be aligned on a 16-byte boundary. */
typedef struct _libc_vrstate
{
unsigned int vrregs[32][4];
unsigned int vrsave;
unsigned int _pad[2];
unsigned int vscr;
} vrregset_t;
/* Context to describe whole processor state. */
typedef struct
{
gregset_t gregs;
fpregset_t fpregs;
vrregset_t vrregs __attribute__((__aligned__(16)));
} mcontext_t;
#else
/* For 64-bit kernels with Altivec support, a machine context is exactly
* a sigcontext. For older kernel (without Altivec) the sigcontext matches
* the mcontext upto but not including the v_regs field. For kernels that
* don't AT_HWCAP or return AT_HWCAP without PPC_FEATURE_HAS_ALTIVEC the
* v_regs field may not exit and should not be referenced. The v_regd field
* can be refernced safely only after verifying that PPC_FEATURE_HAS_ALTIVEC
* is set in AT_HWCAP. */
/* Number of general registers. */
# define NGREG 48 /* includes r0-r31, nip, msr, lr, etc. */
# define NFPREG 33 /* includes fp0-fp31 &fpscr. */
# define NVRREG 34 /* includes v0-v31, vscr, & vrsave in split vectors */
typedef unsigned long gregset_t[NGREG];
typedef double fpregset_t[NFPREG];
/* Container for Altivec/VMX Vector Status and Control Register. Only 32-bits
but can only be copied to/from a 128-bit vector register. So we allocated
a whole quadword speedup save/restore. */
typedef struct _libc_vscr
{
unsigned int __pad[3];
unsigned int vscr_word;
} vscr_t;
/* Container for Altivec/VMX registers and status.
Must to be aligned on a 16-byte boundary. */
typedef struct _libc_vrstate
{
unsigned int vrregs[32][4];
vscr_t vscr;
unsigned int vrsave;
unsigned int __pad[3];
} vrregset_t __attribute__((__aligned__(16)));
typedef struct {
unsigned long __unused[4];
int signal;
int __pad0;
unsigned long handler;
unsigned long oldmask;
struct pt_regs *regs;
gregset_t gp_regs;
fpregset_t fp_regs;
/*
* To maintain compatibility with current implementations the sigcontext is
* extended by appending a pointer (v_regs) to a quadword type (elf_vrreg_t)
* followed by an unstructured (vmx_reserve) field of 69 doublewords. This
* allows the array of vector registers to be quadword aligned independent of
* the alignment of the containing sigcontext or ucontext. It is the
* responsibility of the code setting the sigcontext to set this pointer to
* either NULL (if this processor does not support the VMX feature) or the
* address of the first quadword within the allocated (vmx_reserve) area.
*
* The pointer (v_regs) of vector type (elf_vrreg_t) is essentually
* an array of 34 quadword entries. The entries with
* indexes 0-31 contain the corresponding vector registers. The entry with
* index 32 contains the vscr as the last word (offset 12) within the
* quadword. This allows the vscr to be stored as either a quadword (since
* it must be copied via a vector register to/from storage) or as a word.
* The entry with index 33 contains the vrsave as the first word (offset 0)
* within the quadword.
*/
vrregset_t *v_regs;
long vmx_reserve[NVRREG+NVRREG+1];
} mcontext_t;
#endif
/* Userlevel context. */
typedef struct ucontext
{
unsigned long int uc_flags;
struct ucontext *uc_link;
stack_t uc_stack;
#if __WORDSIZE == 32
/*
* These fields are set up this way to maximize source and
* binary compatibility with code written for the old
* ucontext_t definition, which didn't include space for the
* registers.
*
* Different versions of the kernel have stored the registers on
* signal delivery at different offsets from the ucontext struct.
* Programs should thus use the uc_mcontext.uc_regs pointer to
* find where the registers are actually stored. The registers
* will be stored within the ucontext_t struct but not necessarily
* at a fixed address. As a side-effect, this lets us achieve
* 16-byte alignment for the register storage space if the
* Altivec registers are to be saved, without requiring 16-byte
* alignment on the whole ucontext_t.
*
* The uc_mcontext.regs field is included for source compatibility
* with programs written against the older ucontext_t definition,
* and its name should therefore not change. The uc_pad field
* is for binary compatibility with programs compiled against the
* old ucontext_t; it ensures that uc_mcontext.regs and uc_sigmask
* are at the same offset as previously.
*/
int uc_pad[7];
union uc_regs_ptr {
struct pt_regs *regs;
mcontext_t *uc_regs;
} uc_mcontext;
sigset_t uc_sigmask;
char uc_reg_space[sizeof(mcontext_t) + 12]; /* last for extensibility */
#else /* 64-bit */
sigset_t uc_sigmask;
mcontext_t uc_mcontext; /* last for extensibility */
#endif
} ucontext_t;
#endif /* sys/ucontext.h */