master
 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
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	struct pt_regs	*regs;
26#ifdef __powerpc64__
27	elf_gregset_t	gp_regs;
28	elf_fpregset_t	fp_regs;
29/*
30 * To maintain compatibility with current implementations the sigcontext is
31 * extended by appending a pointer (v_regs) to a quadword type (elf_vrreg_t)
32 * followed by an unstructured (vmx_reserve) field of 101 doublewords. This
33 * allows the array of vector registers to be quadword aligned independent of
34 * the alignment of the containing sigcontext or ucontext. It is the
35 * responsibility of the code setting the sigcontext to set this pointer to
36 * either NULL (if this processor does not support the VMX feature) or the
37 * address of the first quadword within the allocated (vmx_reserve) area.
38 *
39 * The pointer (v_regs) of vector type (elf_vrreg_t) is type compatible with
40 * an array of 34 quadword entries (elf_vrregset_t).  The entries with
41 * indexes 0-31 contain the corresponding vector registers.  The entry with
42 * index 32 contains the vscr as the last word (offset 12) within the
43 * quadword.  This allows the vscr to be stored as either a quadword (since
44 * it must be copied via a vector register to/from storage) or as a word.
45 * The entry with index 33 contains the vrsave as the first word (offset 0)
46 * within the quadword.
47 *
48 * Part of the VSX data is stored here also by extending vmx_restore
49 * by an additional 32 double words.  Architecturally the layout of
50 * the VSR registers and how they overlap on top of the legacy FPR and
51 * VR registers is shown below:
52 *
53 *                    VSR doubleword 0               VSR doubleword 1
54 *           ----------------------------------------------------------------
55 *   VSR[0]  |             FPR[0]            |                              |
56 *           ----------------------------------------------------------------
57 *   VSR[1]  |             FPR[1]            |                              |
58 *           ----------------------------------------------------------------
59 *           |              ...              |                              |
60 *           |              ...              |                              |
61 *           ----------------------------------------------------------------
62 *   VSR[30] |             FPR[30]           |                              |
63 *           ----------------------------------------------------------------
64 *   VSR[31] |             FPR[31]           |                              |
65 *           ----------------------------------------------------------------
66 *   VSR[32] |                             VR[0]                            |
67 *           ----------------------------------------------------------------
68 *   VSR[33] |                             VR[1]                            |
69 *           ----------------------------------------------------------------
70 *           |                              ...                             |
71 *           |                              ...                             |
72 *           ----------------------------------------------------------------
73 *   VSR[62] |                             VR[30]                           |
74 *           ----------------------------------------------------------------
75 *   VSR[63] |                             VR[31]                           |
76 *           ----------------------------------------------------------------
77 *
78 * FPR/VSR 0-31 doubleword 0 is stored in fp_regs, and VMX/VSR 32-63
79 * is stored at the start of vmx_reserve.  vmx_reserve is extended for
80 * backwards compatility to store VSR 0-31 doubleword 1 after the VMX
81 * registers and vscr/vrsave.
82 */
83	elf_vrreg_t	*v_regs;
84	long		vmx_reserve[ELF_NVRREG + ELF_NVRREG + 1 + 32];
85#endif
86};
87
88#endif /* _ASM_POWERPC_SIGCONTEXT_H */