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 <asm/uaccess.h>
37 #include <asm/ucontext.h>
38 #include <asm/system.h>
39 #include <asm/fpu.h>
40 #include <asm/cpu-features.h>
41 #include <asm/war.h>
42 #include <asm/vdso.h>
43
44 #include "signal-common.h"
45
46 /*
47 * Including <asm/unistd.h> would give use the 64-bit syscall numbers ...
48 */
49 #define __NR_N32_restart_syscall 6214
50
51 extern int setup_sigcontext(struct pt_regs *, struct sigcontext __user *);
52 extern int restore_sigcontext(struct pt_regs *, struct sigcontext __user *);
53
54
55 /* IRIX compatible stack_t */
56 typedef struct sigaltstack32 {
57 s32 ss_sp;
58 compat_size_t ss_size;
59 int ss_flags;
60 } stack32_t;
61
62 struct ucontextn32 {
63 u32 uc_flags;
64 s32 uc_link;
65 stack32_t uc_stack;
66 struct sigcontext uc_mcontext;
67 compat_sigset_t uc_sigmask; /* mask last for extensibility */
68 };
69
70 struct rt_sigframe_n32 {
71 u32 rs_ass[4]; /* argument save space for o32 */
72 u32 rs_pad[2]; /* Was: signal trampoline */
73 struct compat_siginfo rs_info;
74 struct ucontextn32 rs_uc;
75 };
76
77 extern void sigset_from_compat(sigset_t *set, compat_sigset_t *compat);
78
sysn32_rt_sigsuspend(nabi_no_regargs struct pt_regs regs)79 asmlinkage int sysn32_rt_sigsuspend(nabi_no_regargs struct pt_regs regs)
80 {
81 compat_sigset_t __user *unewset;
82 compat_sigset_t uset;
83 size_t sigsetsize;
84 sigset_t newset;
85
86 /* XXX Don't preclude handling different sized sigset_t's. */
87 sigsetsize = regs.regs[5];
88 if (sigsetsize != sizeof(sigset_t))
89 return -EINVAL;
90
91 unewset = (compat_sigset_t __user *) regs.regs[4];
92 if (copy_from_user(&uset, unewset, sizeof(uset)))
93 return -EFAULT;
94 sigset_from_compat(&newset, &uset);
95 sigdelsetmask(&newset, ~_BLOCKABLE);
96
97 spin_lock_irq(¤t->sighand->siglock);
98 current->saved_sigmask = current->blocked;
99 current->blocked = newset;
100 recalc_sigpending();
101 spin_unlock_irq(¤t->sighand->siglock);
102
103 current->state = TASK_INTERRUPTIBLE;
104 schedule();
105 set_thread_flag(TIF_RESTORE_SIGMASK);
106 return -ERESTARTNOHAND;
107 }
108
sysn32_rt_sigreturn(nabi_no_regargs struct pt_regs regs)109 asmlinkage void sysn32_rt_sigreturn(nabi_no_regargs struct pt_regs regs)
110 {
111 struct rt_sigframe_n32 __user *frame;
112 mm_segment_t old_fs;
113 sigset_t set;
114 stack_t st;
115 s32 sp;
116 int sig;
117
118 frame = (struct rt_sigframe_n32 __user *) regs.regs[29];
119 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
120 goto badframe;
121 if (__copy_conv_sigset_from_user(&set, &frame->rs_uc.uc_sigmask))
122 goto badframe;
123
124 sigdelsetmask(&set, ~_BLOCKABLE);
125 spin_lock_irq(¤t->sighand->siglock);
126 current->blocked = set;
127 recalc_sigpending();
128 spin_unlock_irq(¤t->sighand->siglock);
129
130 sig = restore_sigcontext(®s, &frame->rs_uc.uc_mcontext);
131 if (sig < 0)
132 goto badframe;
133 else if (sig)
134 force_sig(sig, current);
135
136 /* The ucontext contains a stack32_t, so we must convert! */
137 if (__get_user(sp, &frame->rs_uc.uc_stack.ss_sp))
138 goto badframe;
139 st.ss_sp = (void __user *)(long) sp;
140 if (__get_user(st.ss_size, &frame->rs_uc.uc_stack.ss_size))
141 goto badframe;
142 if (__get_user(st.ss_flags, &frame->rs_uc.uc_stack.ss_flags))
143 goto badframe;
144
145 /* It is more difficult to avoid calling this function than to
146 call it and ignore errors. */
147 old_fs = get_fs();
148 set_fs(KERNEL_DS);
149 do_sigaltstack((stack_t __user *)&st, NULL, regs.regs[29]);
150 set_fs(old_fs);
151
152
153 /*
154 * Don't let your children do this ...
155 */
156 __asm__ __volatile__(
157 "move\t$29, %0\n\t"
158 "j\tsyscall_exit"
159 :/* no outputs */
160 :"r" (®s));
161 /* Unreached */
162
163 badframe:
164 force_sig(SIGSEGV, current);
165 }
166
setup_rt_frame_n32(void * sig_return,struct k_sigaction * ka,struct pt_regs * regs,int signr,sigset_t * set,siginfo_t * info)167 static int setup_rt_frame_n32(void *sig_return, struct k_sigaction *ka,
168 struct pt_regs *regs, int signr, sigset_t *set, siginfo_t *info)
169 {
170 struct rt_sigframe_n32 __user *frame;
171 int err = 0;
172 s32 sp;
173
174 frame = get_sigframe(ka, regs, sizeof(*frame));
175 if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
176 goto give_sigsegv;
177
178 /* Create siginfo. */
179 err |= copy_siginfo_to_user32(&frame->rs_info, info);
180
181 /* Create the ucontext. */
182 err |= __put_user(0, &frame->rs_uc.uc_flags);
183 err |= __put_user(0, &frame->rs_uc.uc_link);
184 sp = (int) (long) current->sas_ss_sp;
185 err |= __put_user(sp,
186 &frame->rs_uc.uc_stack.ss_sp);
187 err |= __put_user(sas_ss_flags(regs->regs[29]),
188 &frame->rs_uc.uc_stack.ss_flags);
189 err |= __put_user(current->sas_ss_size,
190 &frame->rs_uc.uc_stack.ss_size);
191 err |= setup_sigcontext(regs, &frame->rs_uc.uc_mcontext);
192 err |= __copy_conv_sigset_to_user(&frame->rs_uc.uc_sigmask, set);
193
194 if (err)
195 goto give_sigsegv;
196
197 /*
198 * Arguments to signal handler:
199 *
200 * a0 = signal number
201 * a1 = 0 (should be cause)
202 * a2 = pointer to ucontext
203 *
204 * $25 and c0_epc point to the signal handler, $29 points to
205 * the struct rt_sigframe.
206 */
207 regs->regs[ 4] = signr;
208 regs->regs[ 5] = (unsigned long) &frame->rs_info;
209 regs->regs[ 6] = (unsigned long) &frame->rs_uc;
210 regs->regs[29] = (unsigned long) frame;
211 regs->regs[31] = (unsigned long) sig_return;
212 regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler;
213
214 DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
215 current->comm, current->pid,
216 frame, regs->cp0_epc, regs->regs[31]);
217
218 return 0;
219
220 give_sigsegv:
221 force_sigsegv(signr, current);
222 return -EFAULT;
223 }
224
225 struct mips_abi mips_abi_n32 = {
226 .setup_rt_frame = setup_rt_frame_n32,
227 .rt_signal_return_offset =
228 offsetof(struct mips_vdso, n32_rt_signal_trampoline),
229 .restart = __NR_N32_restart_syscall
230 };
231