2 * Port on Texas Instruments TMS320C6x architecture
4 * Copyright (C) 2004, 2006, 2009, 2010, 2011 Texas Instruments Incorporated
5 * Author: Aurelien Jacquiot (aurelien.jacquiot@jaluna.com)
7 * Updated for 2.6.34: Mark Salter <msalter@redhat.com>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
14 #include <linux/kernel.h>
15 #include <linux/uaccess.h>
16 #include <linux/syscalls.h>
17 #include <linux/tracehook.h>
19 #include <asm/ucontext.h>
20 #include <asm/cacheflush.h>
23 #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
26 * Do a signal return, undo the signal stack.
29 #define RETCODE_SIZE (9 << 2) /* 9 instructions = 36 bytes */
32 struct siginfo __user *pinfo;
36 unsigned long retcode[RETCODE_SIZE >> 2];
39 static int restore_sigcontext(struct pt_regs *regs,
40 struct sigcontext __user *sc)
44 /* The access_ok check was done by caller, so use __get_user here */
45 #define COPY(x) (err |= __get_user(regs->x, &sc->sc_##x))
47 COPY(sp); COPY(a4); COPY(b4); COPY(a6); COPY(b6); COPY(a8); COPY(b8);
48 COPY(a0); COPY(a1); COPY(a2); COPY(a3); COPY(a5); COPY(a7); COPY(a9);
49 COPY(b0); COPY(b1); COPY(b2); COPY(b3); COPY(b5); COPY(b7); COPY(b9);
51 COPY(a16); COPY(a17); COPY(a18); COPY(a19);
52 COPY(a20); COPY(a21); COPY(a22); COPY(a23);
53 COPY(a24); COPY(a25); COPY(a26); COPY(a27);
54 COPY(a28); COPY(a29); COPY(a30); COPY(a31);
55 COPY(b16); COPY(b17); COPY(b18); COPY(b19);
56 COPY(b20); COPY(b21); COPY(b22); COPY(b23);
57 COPY(b24); COPY(b25); COPY(b26); COPY(b27);
58 COPY(b28); COPY(b29); COPY(b30); COPY(b31);
67 asmlinkage int do_rt_sigreturn(struct pt_regs *regs)
69 struct rt_sigframe __user *frame;
73 * Since we stacked the signal on a dword boundary,
74 * 'sp' should be dword aligned here. If it's
75 * not, then the user is trying to mess with us.
80 frame = (struct rt_sigframe __user *) ((unsigned long) regs->sp + 8);
82 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
84 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
87 sigdelsetmask(&set, ~_BLOCKABLE);
88 set_current_blocked(&set);
90 if (restore_sigcontext(regs, &frame->uc.uc_mcontext))
96 force_sig(SIGSEGV, current);
100 static int setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs,
105 err |= __put_user(mask, &sc->sc_mask);
107 /* The access_ok check was done by caller, so use __put_user here */
108 #define COPY(x) (err |= __put_user(regs->x, &sc->sc_##x))
110 COPY(sp); COPY(a4); COPY(b4); COPY(a6); COPY(b6); COPY(a8); COPY(b8);
111 COPY(a0); COPY(a1); COPY(a2); COPY(a3); COPY(a5); COPY(a7); COPY(a9);
112 COPY(b0); COPY(b1); COPY(b2); COPY(b3); COPY(b5); COPY(b7); COPY(b9);
114 COPY(a16); COPY(a17); COPY(a18); COPY(a19);
115 COPY(a20); COPY(a21); COPY(a22); COPY(a23);
116 COPY(a24); COPY(a25); COPY(a26); COPY(a27);
117 COPY(a28); COPY(a29); COPY(a30); COPY(a31);
118 COPY(b16); COPY(b17); COPY(b18); COPY(b19);
119 COPY(b20); COPY(b21); COPY(b22); COPY(b23);
120 COPY(b24); COPY(b25); COPY(b26); COPY(b27);
121 COPY(b28); COPY(b29); COPY(b30); COPY(b31);
130 static inline void __user *get_sigframe(struct k_sigaction *ka,
131 struct pt_regs *regs,
132 unsigned long framesize)
134 unsigned long sp = regs->sp;
137 * This is the X/Open sanctioned signal stack switching.
139 if ((ka->sa.sa_flags & SA_ONSTACK) && sas_ss_flags(sp) == 0)
140 sp = current->sas_ss_sp + current->sas_ss_size;
143 * No matter what happens, 'sp' must be dword
144 * aligned. Otherwise, nasty things will happen
146 return (void __user *)((sp - framesize) & ~7);
149 static int setup_rt_frame(int signr, struct k_sigaction *ka, siginfo_t *info,
150 sigset_t *set, struct pt_regs *regs)
152 struct rt_sigframe __user *frame;
153 unsigned long __user *retcode;
156 frame = get_sigframe(ka, regs, sizeof(*frame));
158 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
161 err |= __put_user(&frame->info, &frame->pinfo);
162 err |= __put_user(&frame->uc, &frame->puc);
163 err |= copy_siginfo_to_user(&frame->info, info);
165 /* Clear all the bits of the ucontext we don't use. */
166 err |= __clear_user(&frame->uc, offsetof(struct ucontext, uc_mcontext));
168 err |= setup_sigcontext(&frame->uc.uc_mcontext, regs, set->sig[0]);
169 err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
171 /* Set up to return from userspace */
172 retcode = (unsigned long __user *) &frame->retcode;
174 /* The access_ok check was done above, so use __put_user here */
175 #define COPY(x) (err |= __put_user(x, retcode++))
177 COPY(0x0000002AUL | (__NR_rt_sigreturn << 7));
178 /* MVK __NR_rt_sigreturn,B0 */
179 COPY(0x10000000UL); /* SWE */
180 COPY(0x00006000UL); /* NOP 4 */
181 COPY(0x00006000UL); /* NOP 4 */
182 COPY(0x00006000UL); /* NOP 4 */
183 COPY(0x00006000UL); /* NOP 4 */
184 COPY(0x00006000UL); /* NOP 4 */
185 COPY(0x00006000UL); /* NOP 4 */
186 COPY(0x00006000UL); /* NOP 4 */
193 flush_icache_range((unsigned long) &frame->retcode,
194 (unsigned long) &frame->retcode + RETCODE_SIZE);
196 retcode = (unsigned long __user *) &frame->retcode;
198 /* Change user context to branch to signal handler */
199 regs->sp = (unsigned long) frame - 8;
200 regs->b3 = (unsigned long) retcode;
201 regs->pc = (unsigned long) ka->sa.sa_handler;
203 /* Give the signal number to the handler */
207 * For realtime signals we must also set the second and third
208 * arguments for the signal handler.
209 * -- Peter Maydell <pmaydell@chiark.greenend.org.uk> 2000-12-06
211 regs->b4 = (unsigned long)&frame->info;
212 regs->a6 = (unsigned long)&frame->uc;
217 force_sigsegv(signr, current);
222 handle_restart(struct pt_regs *regs, struct k_sigaction *ka, int has_handler)
225 case -ERESTARTNOHAND:
232 if (has_handler && !(ka->sa.sa_flags & SA_RESTART)) {
237 case -ERESTARTNOINTR:
239 regs->a4 = regs->orig_a4;
246 * handle the actual delivery of a signal to userspace
248 static int handle_signal(int sig,
249 siginfo_t *info, struct k_sigaction *ka,
250 sigset_t *oldset, struct pt_regs *regs,
255 /* Are we from a system call? */
257 /* If so, check system call restarting.. */
259 case -ERESTART_RESTARTBLOCK:
260 case -ERESTARTNOHAND:
265 if (!(ka->sa.sa_flags & SA_RESTART)) {
271 case -ERESTARTNOINTR:
272 regs->a4 = regs->orig_a4;
277 /* Set up the stack frame */
278 ret = setup_rt_frame(sig, ka, info, oldset, regs);
280 block_sigmask(ka, sig);
286 * handle a potential signal
288 static void do_signal(struct pt_regs *regs, int syscall)
290 struct k_sigaction ka;
295 /* we want the common case to go fast, which is why we may in certain
296 * cases get here from kernel mode */
297 if (!user_mode(regs))
300 if (test_thread_flag(TIF_RESTORE_SIGMASK))
301 oldset = ¤t->saved_sigmask;
303 oldset = ¤t->blocked;
305 signr = get_signal_to_deliver(&info, &ka, regs, NULL);
307 if (handle_signal(signr, &info, &ka, oldset,
308 regs, syscall) == 0) {
309 /* a signal was successfully delivered; the saved
310 * sigmask will have been stored in the signal frame,
311 * and will be restored by sigreturn, so we can simply
312 * clear the TIF_RESTORE_SIGMASK flag */
313 if (test_thread_flag(TIF_RESTORE_SIGMASK))
314 clear_thread_flag(TIF_RESTORE_SIGMASK);
316 tracehook_signal_handler(signr, &info, &ka, regs, 0);
322 /* did we come from a system call? */
324 /* restart the system call - no handlers present */
326 case -ERESTARTNOHAND:
328 case -ERESTARTNOINTR:
329 regs->a4 = regs->orig_a4;
333 case -ERESTART_RESTARTBLOCK:
334 regs->a4 = regs->orig_a4;
335 regs->b0 = __NR_restart_syscall;
341 /* if there's no signal to deliver, we just put the saved sigmask
343 if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
344 clear_thread_flag(TIF_RESTORE_SIGMASK);
345 sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL);
350 * notification of userspace execution resumption
351 * - triggered by current->work.notify_resume
353 asmlinkage void do_notify_resume(struct pt_regs *regs, u32 thread_info_flags,
356 /* deal with pending signal delivery */
357 if (thread_info_flags & ((1 << TIF_SIGPENDING) |
358 (1 << TIF_RESTORE_SIGMASK)))
359 do_signal(regs, syscall);
361 if (thread_info_flags & (1 << TIF_NOTIFY_RESUME)) {
362 clear_thread_flag(TIF_NOTIFY_RESUME);
363 tracehook_notify_resume(regs);
364 if (current->replacement_session_keyring)
365 key_replace_session_keyring();