xref: /openbmc/linux/arch/parisc/kernel/signal32.h (revision c819e2cf)
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 int copy_siginfo_to_user32 (compat_siginfo_t __user *to, const siginfo_t *from);
38 int copy_siginfo_from_user32 (siginfo_t *to, compat_siginfo_t __user *from);
39 
40 /* In a deft move of uber-hackery, we decide to carry the top half of all
41  * 64-bit registers in a non-portable, non-ABI, hidden structure.
42  * Userspace can read the hidden structure if it *wants* but is never
43  * guaranteed to be in the same place. In fact the uc_sigmask from the
44  * ucontext_t structure may push the hidden register file downards
45  */
46 struct compat_regfile {
47         /* Upper half of all the 64-bit registers that were truncated
48            on a copy to a 32-bit userspace */
49         compat_int_t rf_gr[32];
50         compat_int_t rf_iasq[2];
51         compat_int_t rf_iaoq[2];
52         compat_int_t rf_sar;
53 };
54 
55 #define COMPAT_SIGRETURN_TRAMP 4
56 #define COMPAT_SIGRESTARTBLOCK_TRAMP 5
57 #define COMPAT_TRAMP_SIZE (COMPAT_SIGRETURN_TRAMP + \
58 				COMPAT_SIGRESTARTBLOCK_TRAMP)
59 
60 struct compat_rt_sigframe {
61         /* XXX: Must match trampoline size in arch/parisc/kernel/signal.c
62                 Secondary to that it must protect the ERESTART_RESTARTBLOCK
63                 trampoline we left on the stack (we were bad and didn't
64                 change sp so we could run really fast.) */
65         compat_uint_t tramp[COMPAT_TRAMP_SIZE];
66         compat_siginfo_t info;
67         struct compat_ucontext uc;
68         /* Hidden location of truncated registers, *must* be last. */
69         struct compat_regfile regs;
70 };
71 
72 /*
73  * The 32-bit ABI wants at least 48 bytes for a function call frame:
74  * 16 bytes for arg0-arg3, and 32 bytes for magic (the only part of
75  * which Linux/parisc uses is sp-20 for the saved return pointer...)
76  * Then, the stack pointer must be rounded to a cache line (64 bytes).
77  */
78 #define SIGFRAME32              64
79 #define FUNCTIONCALLFRAME32     48
80 #define PARISC_RT_SIGFRAME_SIZE32 (((sizeof(struct compat_rt_sigframe) + FUNCTIONCALLFRAME32) + SIGFRAME32) & -SIGFRAME32)
81 
82 void sigset_32to64(sigset_t *s64, compat_sigset_t *s32);
83 void sigset_64to32(compat_sigset_t *s32, sigset_t *s64);
84 long restore_sigcontext32(struct compat_sigcontext __user *sc,
85 		struct compat_regfile __user *rf,
86 		struct pt_regs *regs);
87 long setup_sigcontext32(struct compat_sigcontext __user *sc,
88 		struct compat_regfile __user *rf,
89 		struct pt_regs *regs, int in_syscall);
90 
91 #endif
92