1 /*
2 * Copyright (C) 2003 Broadcom Corporation
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version 2
7 * of the License, or (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
17 */
18 #include <linux/cache.h>
19 #include <linux/sched.h>
20 #include <linux/mm.h>
21 #include <linux/smp.h>
22 #include <linux/kernel.h>
23 #include <linux/signal.h>
24 #include <linux/errno.h>
25 #include <linux/wait.h>
26 #include <linux/ptrace.h>
27 #include <linux/unistd.h>
28 #include <linux/compat.h>
29 #include <linux/bitops.h>
30
31 #include <asm/abi.h>
32 #include <asm/asm.h>
33 #include <asm/cacheflush.h>
34 #include <asm/compat-signal.h>
35 #include <asm/sim.h>
36 #include <linux/uaccess.h>
37 #include <asm/ucontext.h>
38 #include <asm/fpu.h>
39 #include <asm/cpu-features.h>
40 #include <asm/war.h>
41
42 #include "signal-common.h"
43
44 /*
45 * Including <asm/unistd.h> would give use the 64-bit syscall numbers ...
46 */
47 #define __NR_N32_restart_syscall 6214
48
49 extern int setup_sigcontext(struct pt_regs *, struct sigcontext __user *);
50 extern int restore_sigcontext(struct pt_regs *, struct sigcontext __user *);
51
52 struct ucontextn32 {
53 u32 uc_flags;
54 s32 uc_link;
55 compat_stack_t uc_stack;
56 struct sigcontext uc_mcontext;
57 compat_sigset_t uc_sigmask; /* mask last for extensibility */
58 };
59
60 struct rt_sigframe_n32 {
61 u32 rs_ass[4]; /* argument save space for o32 */
62 u32 rs_pad[2]; /* Was: signal trampoline */
63 struct compat_siginfo rs_info;
64 struct ucontextn32 rs_uc;
65 };
66
sysn32_rt_sigreturn(void)67 asmlinkage void sysn32_rt_sigreturn(void)
68 {
69 struct rt_sigframe_n32 __user *frame;
70 struct pt_regs *regs;
71 sigset_t set;
72 int sig;
73
74 regs = current_pt_regs();
75 frame = (struct rt_sigframe_n32 __user *)regs->regs[29];
76 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
77 goto badframe;
78 if (__copy_conv_sigset_from_user(&set, &frame->rs_uc.uc_sigmask))
79 goto badframe;
80
81 set_current_blocked(&set);
82
83 sig = restore_sigcontext(regs, &frame->rs_uc.uc_mcontext);
84 if (sig < 0)
85 goto badframe;
86 else if (sig)
87 force_sig(sig, current);
88
89 if (compat_restore_altstack(&frame->rs_uc.uc_stack))
90 goto badframe;
91
92 /*
93 * Don't let your children do this ...
94 */
95 __asm__ __volatile__(
96 "move\t$29, %0\n\t"
97 "j\tsyscall_exit"
98 : /* no outputs */
99 : "r" (regs));
100 /* Unreached */
101
102 badframe:
103 force_sig(SIGSEGV, current);
104 }
105
setup_rt_frame_n32(void * sig_return,struct ksignal * ksig,struct pt_regs * regs,sigset_t * set)106 static int setup_rt_frame_n32(void *sig_return, struct ksignal *ksig,
107 struct pt_regs *regs, sigset_t *set)
108 {
109 struct rt_sigframe_n32 __user *frame;
110 int err = 0;
111
112 frame = get_sigframe(ksig, regs, sizeof(*frame));
113 if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
114 return -EFAULT;
115
116 /* Create siginfo. */
117 err |= copy_siginfo_to_user32(&frame->rs_info, &ksig->info);
118
119 /* Create the ucontext. */
120 err |= __put_user(0, &frame->rs_uc.uc_flags);
121 err |= __put_user(0, &frame->rs_uc.uc_link);
122 err |= __compat_save_altstack(&frame->rs_uc.uc_stack, regs->regs[29]);
123 err |= setup_sigcontext(regs, &frame->rs_uc.uc_mcontext);
124 err |= __copy_conv_sigset_to_user(&frame->rs_uc.uc_sigmask, set);
125
126 if (err)
127 return -EFAULT;
128
129 /*
130 * Arguments to signal handler:
131 *
132 * a0 = signal number
133 * a1 = 0 (should be cause)
134 * a2 = pointer to ucontext
135 *
136 * $25 and c0_epc point to the signal handler, $29 points to
137 * the struct rt_sigframe.
138 */
139 regs->regs[ 4] = ksig->sig;
140 regs->regs[ 5] = (unsigned long) &frame->rs_info;
141 regs->regs[ 6] = (unsigned long) &frame->rs_uc;
142 regs->regs[29] = (unsigned long) frame;
143 regs->regs[31] = (unsigned long) sig_return;
144 regs->cp0_epc = regs->regs[25] = (unsigned long) ksig->ka.sa.sa_handler;
145
146 DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
147 current->comm, current->pid,
148 frame, regs->cp0_epc, regs->regs[31]);
149
150 return 0;
151 }
152
153 struct mips_abi mips_abi_n32 = {
154 .setup_rt_frame = setup_rt_frame_n32,
155 .restart = __NR_N32_restart_syscall,
156
157 .off_sc_fpregs = offsetof(struct sigcontext, sc_fpregs),
158 .off_sc_fpc_csr = offsetof(struct sigcontext, sc_fpc_csr),
159 .off_sc_used_math = offsetof(struct sigcontext, sc_used_math),
160
161 .vdso = &vdso_image_n32,
162 };
163
