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 
17 struct 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	__user *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	__user *v_regs;
84 	long		vmx_reserve[ELF_NVRREG + ELF_NVRREG + 1 + 32];
85 #endif
86 };
87 
88 #endif /* _ASM_POWERPC_SIGCONTEXT_H */
89