LXR linux/arch/parisc/kernel/signal32.h

   1/* SPDX-License-Identifier: GPL-2.0-or-later */
   2/* 
   3 *    Copyright (C) 2001 Matthew Wilcox <willy at parisc-linux.org>
   4 *    Copyright (C) 2003 Carlos O'Donell <carlos at parisc-linux.org>
   5 */
   6#ifndef _PARISC64_KERNEL_SIGNAL32_H
   7#define _PARISC64_KERNEL_SIGNAL32_H
   8
   9#include <linux/compat.h>
  10
  11/* 32-bit ucontext as seen from an 64-bit kernel */
  12struct compat_ucontext {
  13        compat_uint_t uc_flags;
  14        compat_uptr_t uc_link;
  15        compat_stack_t uc_stack;        /* struct compat_sigaltstack (12 bytes)*/
  16        /* FIXME: Pad out to get uc_mcontext to start at an 8-byte aligned boundary */
  17        compat_uint_t pad[1];
  18        struct compat_sigcontext uc_mcontext;
  19        compat_sigset_t uc_sigmask;     /* mask last for extensibility */
  20};
  21
  22/* ELF32 signal handling */
  23
  24/* In a deft move of uber-hackery, we decide to carry the top half of all
  25 * 64-bit registers in a non-portable, non-ABI, hidden structure.
  26 * Userspace can read the hidden structure if it *wants* but is never
  27 * guaranteed to be in the same place. In fact the uc_sigmask from the
  28 * ucontext_t structure may push the hidden register file downards
  29 */
  30struct compat_regfile {
  31        /* Upper half of all the 64-bit registers that were truncated
  32           on a copy to a 32-bit userspace */
  33        compat_int_t rf_gr[32];
  34        compat_int_t rf_iasq[2];
  35        compat_int_t rf_iaoq[2];
  36        compat_int_t rf_sar;
  37};
  38
  39#define COMPAT_SIGRETURN_TRAMP 3
  40#define COMPAT_SIGRESTARTBLOCK_TRAMP 5
  41#define COMPAT_TRAMP_SIZE (COMPAT_SIGRETURN_TRAMP + \
  42                                COMPAT_SIGRESTARTBLOCK_TRAMP)
  43
  44struct compat_rt_sigframe {
  45        /* XXX: Must match trampoline size in arch/parisc/kernel/signal.c
  46                Secondary to that it must protect the ERESTART_RESTARTBLOCK
  47                trampoline we left on the stack (we were bad and didn't
  48                change sp so we could run really fast.) */
  49        compat_uint_t tramp[COMPAT_TRAMP_SIZE];
  50        compat_siginfo_t info;
  51        struct compat_ucontext uc;
  52        /* Hidden location of truncated registers, *must* be last. */
  53        struct compat_regfile regs;
  54};
  55
  56/*
  57 * The 32-bit ABI wants at least 48 bytes for a function call frame:
  58 * 16 bytes for arg0-arg3, and 32 bytes for magic (the only part of
  59 * which Linux/parisc uses is sp-20 for the saved return pointer...)
  60 * Then, the stack pointer must be rounded to a cache line (64 bytes).
  61 */
  62#define SIGFRAME32              64
  63#define FUNCTIONCALLFRAME32     48
  64#define PARISC_RT_SIGFRAME_SIZE32 (((sizeof(struct compat_rt_sigframe) + FUNCTIONCALLFRAME32) + SIGFRAME32) & -SIGFRAME32)
  65
  66long restore_sigcontext32(struct compat_sigcontext __user *sc, 
  67                struct compat_regfile __user *rf,
  68                struct pt_regs *regs);
  69long setup_sigcontext32(struct compat_sigcontext __user *sc, 
  70                struct compat_regfile __user *rf,
  71                struct pt_regs *regs, int in_syscall);
  72
  73#endif
  74