xref: /openbmc/linux/arch/parisc/kernel/signal32.h (revision 217188d9)
1 /*
2  *    Copyright (C) 2001 Matthew Wilcox <willy at parisc-linux.org>
3  *    Copyright (C) 2003 Carlos O'Donell <carlos at parisc-linux.org>
4  *
5  *    This program is free software; you can redistribute it and/or modify
6  *    it under the terms of the GNU General Public License as published by
7  *    the Free Software Foundation; either version 2 of the License, or
8  *    (at your option) any later version.
9  *
10  *    This program is distributed in the hope that it will be useful,
11  *    but WITHOUT ANY WARRANTY; without even the implied warranty of
12  *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  *    GNU General Public License for more details.
14  *
15  *    You should have received a copy of the GNU General Public License
16  *    along with this program; if not, write to the Free Software
17  *    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
18  */
19 #ifndef _PARISC64_KERNEL_SIGNAL32_H
20 #define _PARISC64_KERNEL_SIGNAL32_H
21 
22 #include <linux/compat.h>
23 
24 /* 32-bit ucontext as seen from an 64-bit kernel */
25 struct compat_ucontext {
26         compat_uint_t uc_flags;
27         compat_uptr_t uc_link;
28         compat_stack_t uc_stack;        /* struct compat_sigaltstack (12 bytes)*/
29         /* FIXME: Pad out to get uc_mcontext to start at an 8-byte aligned boundary */
30         compat_uint_t pad[1];
31         struct compat_sigcontext uc_mcontext;
32         compat_sigset_t uc_sigmask;     /* mask last for extensibility */
33 };
34 
35 /* ELF32 signal handling */
36 
37 /* In a deft move of uber-hackery, we decide to carry the top half of all
38  * 64-bit registers in a non-portable, non-ABI, hidden structure.
39  * Userspace can read the hidden structure if it *wants* but is never
40  * guaranteed to be in the same place. In fact the uc_sigmask from the
41  * ucontext_t structure may push the hidden register file downards
42  */
43 struct compat_regfile {
44         /* Upper half of all the 64-bit registers that were truncated
45            on a copy to a 32-bit userspace */
46         compat_int_t rf_gr[32];
47         compat_int_t rf_iasq[2];
48         compat_int_t rf_iaoq[2];
49         compat_int_t rf_sar;
50 };
51 
52 #define COMPAT_SIGRETURN_TRAMP 4
53 #define COMPAT_SIGRESTARTBLOCK_TRAMP 5
54 #define COMPAT_TRAMP_SIZE (COMPAT_SIGRETURN_TRAMP + \
55 				COMPAT_SIGRESTARTBLOCK_TRAMP)
56 
57 struct compat_rt_sigframe {
58         /* XXX: Must match trampoline size in arch/parisc/kernel/signal.c
59                 Secondary to that it must protect the ERESTART_RESTARTBLOCK
60                 trampoline we left on the stack (we were bad and didn't
61                 change sp so we could run really fast.) */
62         compat_uint_t tramp[COMPAT_TRAMP_SIZE];
63         compat_siginfo_t info;
64         struct compat_ucontext uc;
65         /* Hidden location of truncated registers, *must* be last. */
66         struct compat_regfile regs;
67 };
68 
69 /*
70  * The 32-bit ABI wants at least 48 bytes for a function call frame:
71  * 16 bytes for arg0-arg3, and 32 bytes for magic (the only part of
72  * which Linux/parisc uses is sp-20 for the saved return pointer...)
73  * Then, the stack pointer must be rounded to a cache line (64 bytes).
74  */
75 #define SIGFRAME32              64
76 #define FUNCTIONCALLFRAME32     48
77 #define PARISC_RT_SIGFRAME_SIZE32 (((sizeof(struct compat_rt_sigframe) + FUNCTIONCALLFRAME32) + SIGFRAME32) & -SIGFRAME32)
78 
79 long restore_sigcontext32(struct compat_sigcontext __user *sc,
80 		struct compat_regfile __user *rf,
81 		struct pt_regs *regs);
82 long setup_sigcontext32(struct compat_sigcontext __user *sc,
83 		struct compat_regfile __user *rf,
84 		struct pt_regs *regs, int in_syscall);
85 
86 #endif
87