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
39struct compat_rt_sigframe {
40	unsigned int tramp[2]; /* holds original return address */
41	compat_siginfo_t info;
42	struct compat_ucontext uc;
43	/* Hidden location of truncated registers, *must* be last. */
44	struct compat_regfile regs;
45};
46
47/*
48 * The 32-bit ABI wants at least 48 bytes for a function call frame:
49 * 16 bytes for arg0-arg3, and 32 bytes for magic (the only part of
50 * which Linux/parisc uses is sp-20 for the saved return pointer...)
51 * Then, the stack pointer must be rounded to a cache line (64 bytes).
52 */
53#define SIGFRAME32              64
54#define FUNCTIONCALLFRAME32     48
55#define PARISC_RT_SIGFRAME_SIZE32 (((sizeof(struct compat_rt_sigframe) + FUNCTIONCALLFRAME32) + SIGFRAME32) & -SIGFRAME32)
56
57long restore_sigcontext32(struct compat_sigcontext __user *sc,
58		struct compat_regfile __user *rf,
59		struct pt_regs *regs);
60long setup_sigcontext32(struct compat_sigcontext __user *sc,
61		struct compat_regfile __user *rf,
62		struct pt_regs *regs, int in_syscall);
63
64#endif
65