]>
Commit | Line | Data |
---|---|---|
cd5b61d6 RK |
1 | /* |
2 | * Signal support for Hexagon processor | |
3 | * | |
7c6a5df4 | 4 | * Copyright (c) 2010-2012, The Linux Foundation. All rights reserved. |
cd5b61d6 RK |
5 | * |
6 | * This program is free software; you can redistribute it and/or modify | |
7 | * it under the terms of the GNU General Public License version 2 and | |
8 | * only version 2 as published by the Free Software Foundation. | |
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., 51 Franklin Street, Fifth Floor, Boston, MA | |
18 | * 02110-1301, USA. | |
19 | */ | |
20 | ||
21 | #include <linux/linkage.h> | |
22 | #include <linux/syscalls.h> | |
cd5b61d6 | 23 | #include <linux/tracehook.h> |
68db0cf1 IM |
24 | #include <linux/sched/task_stack.h> |
25 | ||
cd5b61d6 RK |
26 | #include <asm/registers.h> |
27 | #include <asm/thread_info.h> | |
28 | #include <asm/unistd.h> | |
7c0f6ba6 | 29 | #include <linux/uaccess.h> |
cd5b61d6 RK |
30 | #include <asm/ucontext.h> |
31 | #include <asm/cacheflush.h> | |
32 | #include <asm/signal.h> | |
33 | #include <asm/vdso.h> | |
34 | ||
cd5b61d6 RK |
35 | struct rt_sigframe { |
36 | unsigned long tramp[2]; | |
37 | struct siginfo info; | |
38 | struct ucontext uc; | |
39 | }; | |
40 | ||
8bc77aa4 | 41 | static void __user *get_sigframe(struct ksignal *ksig, struct pt_regs *regs, |
cd5b61d6 RK |
42 | size_t frame_size) |
43 | { | |
8bc77aa4 | 44 | unsigned long sp = sigsp(regs->r29, ksig); |
cd5b61d6 RK |
45 | |
46 | return (void __user *)((sp - frame_size) & ~(sizeof(long long) - 1)); | |
47 | } | |
48 | ||
49 | static int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc) | |
50 | { | |
51 | unsigned long tmp; | |
52 | int err = 0; | |
53 | ||
54 | err |= copy_to_user(&sc->sc_regs.r0, ®s->r00, | |
55 | 32*sizeof(unsigned long)); | |
56 | ||
57 | err |= __put_user(regs->sa0, &sc->sc_regs.sa0); | |
58 | err |= __put_user(regs->lc0, &sc->sc_regs.lc0); | |
59 | err |= __put_user(regs->sa1, &sc->sc_regs.sa1); | |
60 | err |= __put_user(regs->lc1, &sc->sc_regs.lc1); | |
61 | err |= __put_user(regs->m0, &sc->sc_regs.m0); | |
62 | err |= __put_user(regs->m1, &sc->sc_regs.m1); | |
63 | err |= __put_user(regs->usr, &sc->sc_regs.usr); | |
64 | err |= __put_user(regs->preds, &sc->sc_regs.p3_0); | |
65 | err |= __put_user(regs->gp, &sc->sc_regs.gp); | |
66 | err |= __put_user(regs->ugp, &sc->sc_regs.ugp); | |
60c4ba99 RK |
67 | #if CONFIG_HEXAGON_ARCH_VERSION >= 4 |
68 | err |= __put_user(regs->cs0, &sc->sc_regs.cs0); | |
69 | err |= __put_user(regs->cs1, &sc->sc_regs.cs1); | |
70 | #endif | |
cd5b61d6 RK |
71 | tmp = pt_elr(regs); err |= __put_user(tmp, &sc->sc_regs.pc); |
72 | tmp = pt_cause(regs); err |= __put_user(tmp, &sc->sc_regs.cause); | |
73 | tmp = pt_badva(regs); err |= __put_user(tmp, &sc->sc_regs.badva); | |
74 | ||
75 | return err; | |
76 | } | |
77 | ||
78 | static int restore_sigcontext(struct pt_regs *regs, | |
79 | struct sigcontext __user *sc) | |
80 | { | |
81 | unsigned long tmp; | |
82 | int err = 0; | |
83 | ||
84 | err |= copy_from_user(®s->r00, &sc->sc_regs.r0, | |
85 | 32 * sizeof(unsigned long)); | |
86 | ||
87 | err |= __get_user(regs->sa0, &sc->sc_regs.sa0); | |
88 | err |= __get_user(regs->lc0, &sc->sc_regs.lc0); | |
89 | err |= __get_user(regs->sa1, &sc->sc_regs.sa1); | |
90 | err |= __get_user(regs->lc1, &sc->sc_regs.lc1); | |
91 | err |= __get_user(regs->m0, &sc->sc_regs.m0); | |
92 | err |= __get_user(regs->m1, &sc->sc_regs.m1); | |
93 | err |= __get_user(regs->usr, &sc->sc_regs.usr); | |
94 | err |= __get_user(regs->preds, &sc->sc_regs.p3_0); | |
95 | err |= __get_user(regs->gp, &sc->sc_regs.gp); | |
96 | err |= __get_user(regs->ugp, &sc->sc_regs.ugp); | |
60c4ba99 RK |
97 | #if CONFIG_HEXAGON_ARCH_VERSION >= 4 |
98 | err |= __get_user(regs->cs0, &sc->sc_regs.cs0); | |
99 | err |= __get_user(regs->cs1, &sc->sc_regs.cs1); | |
100 | #endif | |
cd5b61d6 RK |
101 | err |= __get_user(tmp, &sc->sc_regs.pc); pt_set_elr(regs, tmp); |
102 | ||
103 | return err; | |
104 | } | |
105 | ||
106 | /* | |
107 | * Setup signal stack frame with siginfo structure | |
108 | */ | |
ac443624 RW |
109 | static int setup_rt_frame(struct ksignal *ksig, sigset_t *set, |
110 | struct pt_regs *regs) | |
cd5b61d6 RK |
111 | { |
112 | int err = 0; | |
113 | struct rt_sigframe __user *frame; | |
114 | struct hexagon_vdso *vdso = current->mm->context.vdso; | |
115 | ||
8bc77aa4 | 116 | frame = get_sigframe(ksig, regs, sizeof(struct rt_sigframe)); |
cd5b61d6 RK |
117 | |
118 | if (!access_ok(VERIFY_WRITE, frame, sizeof(struct rt_sigframe))) | |
ac443624 | 119 | return -EFAULT; |
cd5b61d6 | 120 | |
ac443624 RW |
121 | if (copy_siginfo_to_user(&frame->info, &ksig->info)) |
122 | return -EFAULT; | |
cd5b61d6 RK |
123 | |
124 | /* The on-stack signal trampoline is no longer executed; | |
125 | * however, the libgcc signal frame unwinding code checks for | |
126 | * the presence of these two numeric magic values. | |
127 | */ | |
128 | err |= __put_user(0x7800d166, &frame->tramp[0]); | |
129 | err |= __put_user(0x5400c004, &frame->tramp[1]); | |
130 | err |= setup_sigcontext(regs, &frame->uc.uc_mcontext); | |
131 | err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); | |
da36f98a | 132 | err |= __save_altstack(&frame->uc.uc_stack, user_stack_pointer(regs)); |
cd5b61d6 | 133 | if (err) |
ac443624 | 134 | return -EFAULT; |
cd5b61d6 RK |
135 | |
136 | /* Load r0/r1 pair with signumber/siginfo pointer... */ | |
137 | regs->r0100 = ((unsigned long long)((unsigned long)&frame->info) << 32) | |
ac443624 | 138 | | (unsigned long long)ksig->sig; |
cd5b61d6 RK |
139 | regs->r02 = (unsigned long) &frame->uc; |
140 | regs->r31 = (unsigned long) vdso->rt_signal_trampoline; | |
141 | pt_psp(regs) = (unsigned long) frame; | |
ac443624 | 142 | pt_set_elr(regs, (unsigned long)ksig->ka.sa.sa_handler); |
cd5b61d6 RK |
143 | |
144 | return 0; | |
cd5b61d6 RK |
145 | } |
146 | ||
147 | /* | |
148 | * Setup invocation of signal handler | |
149 | */ | |
ac443624 | 150 | static void handle_signal(struct ksignal *ksig, struct pt_regs *regs) |
cd5b61d6 | 151 | { |
ac443624 RW |
152 | int ret; |
153 | ||
cd5b61d6 RK |
154 | /* |
155 | * If we're handling a signal that aborted a system call, | |
156 | * set up the error return value before adding the signal | |
157 | * frame to the stack. | |
158 | */ | |
159 | ||
160 | if (regs->syscall_nr >= 0) { | |
161 | switch (regs->r00) { | |
162 | case -ERESTART_RESTARTBLOCK: | |
163 | case -ERESTARTNOHAND: | |
164 | regs->r00 = -EINTR; | |
165 | break; | |
166 | case -ERESTARTSYS: | |
ac443624 | 167 | if (!(ksig->ka.sa.sa_flags & SA_RESTART)) { |
cd5b61d6 RK |
168 | regs->r00 = -EINTR; |
169 | break; | |
170 | } | |
171 | /* Fall through */ | |
172 | case -ERESTARTNOINTR: | |
173 | regs->r06 = regs->syscall_nr; | |
174 | pt_set_elr(regs, pt_elr(regs) - 4); | |
175 | regs->r00 = regs->restart_r0; | |
176 | break; | |
177 | default: | |
178 | break; | |
179 | } | |
180 | } | |
181 | ||
182 | /* | |
183 | * Set up the stack frame; not doing the SA_SIGINFO thing. We | |
184 | * only set up the rt_frame flavor. | |
185 | */ | |
cd5b61d6 | 186 | /* If there was an error on setup, no signal was delivered. */ |
ac443624 | 187 | ret = setup_rt_frame(ksig, sigmask_to_save(), regs); |
cd5b61d6 | 188 | |
ac443624 | 189 | signal_setup_done(ret, ksig, test_thread_flag(TIF_SINGLESTEP)); |
cd5b61d6 RK |
190 | } |
191 | ||
192 | /* | |
193 | * Called from return-from-event code. | |
194 | */ | |
a11e67c2 | 195 | void do_signal(struct pt_regs *regs) |
cd5b61d6 | 196 | { |
ac443624 | 197 | struct ksignal ksig; |
cd5b61d6 RK |
198 | |
199 | if (!user_mode(regs)) | |
200 | return; | |
201 | ||
ac443624 RW |
202 | if (get_signal(&ksig)) { |
203 | handle_signal(&ksig, regs); | |
cd5b61d6 RK |
204 | return; |
205 | } | |
206 | ||
cd5b61d6 | 207 | /* |
a11e67c2 | 208 | * No (more) signals; if we came from a system call, handle the restart. |
cd5b61d6 | 209 | */ |
a11e67c2 | 210 | |
cd5b61d6 RK |
211 | if (regs->syscall_nr >= 0) { |
212 | switch (regs->r00) { | |
213 | case -ERESTARTNOHAND: | |
214 | case -ERESTARTSYS: | |
215 | case -ERESTARTNOINTR: | |
216 | regs->r06 = regs->syscall_nr; | |
217 | break; | |
218 | case -ERESTART_RESTARTBLOCK: | |
219 | regs->r06 = __NR_restart_syscall; | |
220 | break; | |
221 | default: | |
222 | goto no_restart; | |
223 | } | |
224 | pt_set_elr(regs, pt_elr(regs) - 4); | |
225 | regs->r00 = regs->restart_r0; | |
226 | } | |
227 | ||
228 | no_restart: | |
229 | /* If there's no signal to deliver, put the saved sigmask back */ | |
51a7b448 | 230 | restore_saved_sigmask(); |
cd5b61d6 RK |
231 | } |
232 | ||
cd5b61d6 RK |
233 | /* |
234 | * Architecture-specific wrappers for signal-related system calls | |
235 | */ | |
cd5b61d6 RK |
236 | |
237 | asmlinkage int sys_rt_sigreturn(void) | |
238 | { | |
99521855 | 239 | struct pt_regs *regs = current_pt_regs(); |
cd5b61d6 RK |
240 | struct rt_sigframe __user *frame; |
241 | sigset_t blocked; | |
242 | ||
ef9b122f | 243 | /* Always make any pending restarted system calls return -EINTR */ |
f56141e3 | 244 | current->restart_block.fn = do_no_restart_syscall; |
ef9b122f | 245 | |
cd5b61d6 RK |
246 | frame = (struct rt_sigframe __user *)pt_psp(regs); |
247 | if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) | |
248 | goto badframe; | |
249 | if (__copy_from_user(&blocked, &frame->uc.uc_sigmask, sizeof(blocked))) | |
250 | goto badframe; | |
251 | ||
43aca324 | 252 | set_current_blocked(&blocked); |
cd5b61d6 RK |
253 | |
254 | if (restore_sigcontext(regs, &frame->uc.uc_mcontext)) | |
255 | goto badframe; | |
256 | ||
257 | /* Restore the user's stack as well */ | |
258 | pt_psp(regs) = regs->r29; | |
259 | ||
a11e67c2 | 260 | regs->syscall_nr = -1; |
cd5b61d6 | 261 | |
1e974c21 | 262 | if (restore_altstack(&frame->uc.uc_stack)) |
cd5b61d6 RK |
263 | goto badframe; |
264 | ||
a11e67c2 | 265 | return regs->r00; |
cd5b61d6 RK |
266 | |
267 | badframe: | |
268 | force_sig(SIGSEGV, current); | |
269 | return 0; | |
270 | } |