1/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
2#ifndef _ASM_POWERPC_SIGCONTEXT_H
3#define _ASM_POWERPC_SIGCONTEXT_H
4
5/*
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 */
11#include <linux/compiler.h>
12#include <asm/ptrace.h>
13#ifdef __powerpc64__
14#include <asm/elf.h>
15#endif
16
17struct sigcontext {
18	unsigned long	_unused[4];
19	int		signal;
20#ifdef __powerpc64__
21	int		_pad0;
22#endif
23	unsigned long	handler;
24	unsigned long	oldmask;
25#ifdef __KERNEL__
26	struct user_pt_regs __user *regs;
27#else
28	struct pt_regs	*regs;
29#endif
30#ifdef __powerpc64__
31	elf_gregset_t	gp_regs;
32	elf_fpregset_t	fp_regs;
33/*
34 * To maintain compatibility with current implementations the sigcontext is
35 * extended by appending a pointer (v_regs) to a quadword type (elf_vrreg_t)
36 * followed by an unstructured (vmx_reserve) field of 101 doublewords. This
37 * allows the array of vector registers to be quadword aligned independent of
38 * the alignment of the containing sigcontext or ucontext. It is the
39 * responsibility of the code setting the sigcontext to set this pointer to
40 * either NULL (if this processor does not support the VMX feature) or the
41 * address of the first quadword within the allocated (vmx_reserve) area.
42 *
43 * The pointer (v_regs) of vector type (elf_vrreg_t) is type compatible with
44 * an array of 34 quadword entries (elf_vrregset_t).  The entries with
45 * indexes 0-31 contain the corresponding vector registers.  The entry with
46 * index 32 contains the vscr as the last word (offset 12) within the
47 * quadword.  This allows the vscr to be stored as either a quadword (since
48 * it must be copied via a vector register to/from storage) or as a word.
49 * The entry with index 33 contains the vrsave as the first word (offset 0)
50 * within the quadword.
51 *
52 * Part of the VSX data is stored here also by extending vmx_restore
53 * by an additional 32 double words.  Architecturally the layout of
54 * the VSR registers and how they overlap on top of the legacy FPR and
55 * VR registers is shown below:
56 *
57 *                    VSR doubleword 0               VSR doubleword 1
58 *           ----------------------------------------------------------------
59 *   VSR[0]  |             FPR[0]            |                              |
60 *           ----------------------------------------------------------------
61 *   VSR[1]  |             FPR[1]            |                              |
62 *           ----------------------------------------------------------------
63 *           |              ...              |                              |
64 *           |              ...              |                              |
65 *           ----------------------------------------------------------------
66 *   VSR[30] |             FPR[30]           |                              |
67 *           ----------------------------------------------------------------
68 *   VSR[31] |             FPR[31]           |                              |
69 *           ----------------------------------------------------------------
70 *   VSR[32] |                             VR[0]                            |
71 *           ----------------------------------------------------------------
72 *   VSR[33] |                             VR[1]                            |
73 *           ----------------------------------------------------------------
74 *           |                              ...                             |
75 *           |                              ...                             |
76 *           ----------------------------------------------------------------
77 *   VSR[62] |                             VR[30]                           |
78 *           ----------------------------------------------------------------
79 *   VSR[63] |                             VR[31]                           |
80 *           ----------------------------------------------------------------
81 *
82 * FPR/VSR 0-31 doubleword 0 is stored in fp_regs, and VMX/VSR 32-63
83 * is stored at the start of vmx_reserve.  vmx_reserve is extended for
84 * backwards compatility to store VSR 0-31 doubleword 1 after the VMX
85 * registers and vscr/vrsave.
86 */
87	elf_vrreg_t	__user *v_regs;
88	long		vmx_reserve[ELF_NVRREG + ELF_NVRREG + 1 + 32];
89#endif
90};
91
92#endif /* _ASM_POWERPC_SIGCONTEXT_H */
93