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