blob: b976820402154a49b3792e7f8c07d7c803416358 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * arch/s390/kernel/signal.c
3 *
Heiko Carstens54dfe5dd2006-02-01 03:06:38 -08004 * Copyright (C) IBM Corp. 1999,2006
Linus Torvalds1da177e2005-04-16 15:20:36 -07005 * Author(s): Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com)
6 *
7 * Based on Intel version
8 *
9 * Copyright (C) 1991, 1992 Linus Torvalds
10 *
11 * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson
12 */
13
Linus Torvalds1da177e2005-04-16 15:20:36 -070014#include <linux/sched.h>
15#include <linux/mm.h>
16#include <linux/smp.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070017#include <linux/kernel.h>
18#include <linux/signal.h>
19#include <linux/errno.h>
20#include <linux/wait.h>
21#include <linux/ptrace.h>
22#include <linux/unistd.h>
23#include <linux/stddef.h>
24#include <linux/tty.h>
25#include <linux/personality.h>
26#include <linux/binfmts.h>
27#include <asm/ucontext.h>
28#include <asm/uaccess.h>
29#include <asm/lowcore.h>
Heiko Carstensa8061702008-04-17 07:46:26 +020030#include "entry.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070031
32#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
33
34
35typedef struct
36{
37 __u8 callee_used_stack[__SIGNAL_FRAMESIZE];
38 struct sigcontext sc;
39 _sigregs sregs;
40 int signo;
41 __u8 retcode[S390_SYSCALL_SIZE];
42} sigframe;
43
44typedef struct
45{
46 __u8 callee_used_stack[__SIGNAL_FRAMESIZE];
47 __u8 retcode[S390_SYSCALL_SIZE];
48 struct siginfo info;
49 struct ucontext uc;
50} rt_sigframe;
51
Linus Torvalds1da177e2005-04-16 15:20:36 -070052/*
53 * Atomically swap in the new signal mask, and wait for a signal.
54 */
55asmlinkage int
Heiko Carstens54dfe5dd2006-02-01 03:06:38 -080056sys_sigsuspend(int history0, int history1, old_sigset_t mask)
Linus Torvalds1da177e2005-04-16 15:20:36 -070057{
Linus Torvalds1da177e2005-04-16 15:20:36 -070058 mask &= _BLOCKABLE;
59 spin_lock_irq(&current->sighand->siglock);
Heiko Carstens54dfe5dd2006-02-01 03:06:38 -080060 current->saved_sigmask = current->blocked;
Linus Torvalds1da177e2005-04-16 15:20:36 -070061 siginitset(&current->blocked, mask);
62 recalc_sigpending();
63 spin_unlock_irq(&current->sighand->siglock);
Linus Torvalds1da177e2005-04-16 15:20:36 -070064
Heiko Carstens54dfe5dd2006-02-01 03:06:38 -080065 current->state = TASK_INTERRUPTIBLE;
66 schedule();
67 set_thread_flag(TIF_RESTORE_SIGMASK);
Linus Torvalds1da177e2005-04-16 15:20:36 -070068
Heiko Carstens54dfe5dd2006-02-01 03:06:38 -080069 return -ERESTARTNOHAND;
Linus Torvalds1da177e2005-04-16 15:20:36 -070070}
71
72asmlinkage long
73sys_sigaction(int sig, const struct old_sigaction __user *act,
74 struct old_sigaction __user *oact)
75{
76 struct k_sigaction new_ka, old_ka;
77 int ret;
78
79 if (act) {
80 old_sigset_t mask;
81 if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
82 __get_user(new_ka.sa.sa_handler, &act->sa_handler) ||
Heiko Carstens12bae232006-10-27 12:39:22 +020083 __get_user(new_ka.sa.sa_restorer, &act->sa_restorer) ||
84 __get_user(new_ka.sa.sa_flags, &act->sa_flags) ||
85 __get_user(mask, &act->sa_mask))
Linus Torvalds1da177e2005-04-16 15:20:36 -070086 return -EFAULT;
Linus Torvalds1da177e2005-04-16 15:20:36 -070087 siginitset(&new_ka.sa.sa_mask, mask);
88 }
89
90 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
91
92 if (!ret && oact) {
93 if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
94 __put_user(old_ka.sa.sa_handler, &oact->sa_handler) ||
Heiko Carstens12bae232006-10-27 12:39:22 +020095 __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer) ||
96 __put_user(old_ka.sa.sa_flags, &oact->sa_flags) ||
97 __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask))
Linus Torvalds1da177e2005-04-16 15:20:36 -070098 return -EFAULT;
Linus Torvalds1da177e2005-04-16 15:20:36 -070099 }
100
101 return ret;
102}
103
104asmlinkage long
Martin Schwidefsky03ff9a22007-04-27 16:01:40 +0200105sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700106{
Martin Schwidefsky03ff9a22007-04-27 16:01:40 +0200107 struct pt_regs *regs = task_pt_regs(current);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700108 return do_sigaltstack(uss, uoss, regs->gprs[15]);
109}
110
111
112
113/* Returns non-zero on fault. */
114static int save_sigregs(struct pt_regs *regs, _sigregs __user *sregs)
115{
Gerald Schaefer6837a8c2006-09-20 15:59:39 +0200116 _sigregs user_sregs;
117
Linus Torvalds1da177e2005-04-16 15:20:36 -0700118 save_access_regs(current->thread.acrs);
119
120 /* Copy a 'clean' PSW mask to the user to avoid leaking
121 information about whether PER is currently on. */
Gerald Schaeferc1821c22007-02-05 21:18:17 +0100122 user_sregs.regs.psw.mask = PSW_MASK_MERGE(psw_user_bits, regs->psw.mask);
Martin Schwidefskyb05e3702006-10-04 20:01:58 +0200123 user_sregs.regs.psw.addr = regs->psw.addr;
124 memcpy(&user_sregs.regs.gprs, &regs->gprs, sizeof(sregs->regs.gprs));
Gerald Schaefer6837a8c2006-09-20 15:59:39 +0200125 memcpy(&user_sregs.regs.acrs, current->thread.acrs,
126 sizeof(sregs->regs.acrs));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700127 /*
128 * We have to store the fp registers to current->thread.fp_regs
129 * to merge them with the emulated registers.
130 */
131 save_fp_regs(&current->thread.fp_regs);
Gerald Schaefer6837a8c2006-09-20 15:59:39 +0200132 memcpy(&user_sregs.fpregs, &current->thread.fp_regs,
133 sizeof(s390_fp_regs));
134 return __copy_to_user(sregs, &user_sregs, sizeof(_sigregs));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700135}
136
137/* Returns positive number on error */
138static int restore_sigregs(struct pt_regs *regs, _sigregs __user *sregs)
139{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700140 int err;
Gerald Schaefer6837a8c2006-09-20 15:59:39 +0200141 _sigregs user_sregs;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700142
143 /* Alwys make any pending restarted system call return -EINTR */
144 current_thread_info()->restart_block.fn = do_no_restart_syscall;
145
Gerald Schaefer6837a8c2006-09-20 15:59:39 +0200146 err = __copy_from_user(&user_sregs, sregs, sizeof(_sigregs));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700147 if (err)
148 return err;
Martin Schwidefskyb05e3702006-10-04 20:01:58 +0200149 regs->psw.mask = PSW_MASK_MERGE(regs->psw.mask,
150 user_sregs.regs.psw.mask);
151 regs->psw.addr = PSW_ADDR_AMODE | user_sregs.regs.psw.addr;
152 memcpy(&regs->gprs, &user_sregs.regs.gprs, sizeof(sregs->regs.gprs));
Gerald Schaefer6837a8c2006-09-20 15:59:39 +0200153 memcpy(&current->thread.acrs, &user_sregs.regs.acrs,
154 sizeof(sregs->regs.acrs));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700155 restore_access_regs(current->thread.acrs);
156
Gerald Schaefer6837a8c2006-09-20 15:59:39 +0200157 memcpy(&current->thread.fp_regs, &user_sregs.fpregs,
158 sizeof(s390_fp_regs));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700159 current->thread.fp_regs.fpc &= FPC_VALID_MASK;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700160
161 restore_fp_regs(&current->thread.fp_regs);
162 regs->trap = -1; /* disable syscall checks */
163 return 0;
164}
165
Martin Schwidefsky03ff9a22007-04-27 16:01:40 +0200166asmlinkage long sys_sigreturn(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700167{
Martin Schwidefsky03ff9a22007-04-27 16:01:40 +0200168 struct pt_regs *regs = task_pt_regs(current);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700169 sigframe __user *frame = (sigframe __user *)regs->gprs[15];
170 sigset_t set;
171
172 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
173 goto badframe;
174 if (__copy_from_user(&set.sig, &frame->sc.oldmask, _SIGMASK_COPY_SIZE))
175 goto badframe;
176
177 sigdelsetmask(&set, ~_BLOCKABLE);
178 spin_lock_irq(&current->sighand->siglock);
179 current->blocked = set;
180 recalc_sigpending();
181 spin_unlock_irq(&current->sighand->siglock);
182
183 if (restore_sigregs(regs, &frame->sregs))
184 goto badframe;
185
186 return regs->gprs[2];
187
188badframe:
189 force_sig(SIGSEGV, current);
190 return 0;
191}
192
Martin Schwidefsky03ff9a22007-04-27 16:01:40 +0200193asmlinkage long sys_rt_sigreturn(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700194{
Martin Schwidefsky03ff9a22007-04-27 16:01:40 +0200195 struct pt_regs *regs = task_pt_regs(current);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700196 rt_sigframe __user *frame = (rt_sigframe __user *)regs->gprs[15];
197 sigset_t set;
198
199 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
200 goto badframe;
201 if (__copy_from_user(&set.sig, &frame->uc.uc_sigmask, sizeof(set)))
202 goto badframe;
203
204 sigdelsetmask(&set, ~_BLOCKABLE);
205 spin_lock_irq(&current->sighand->siglock);
206 current->blocked = set;
207 recalc_sigpending();
208 spin_unlock_irq(&current->sighand->siglock);
209
210 if (restore_sigregs(regs, &frame->uc.uc_mcontext))
211 goto badframe;
212
Cedric Le Goater4e3df372006-01-06 00:19:10 -0800213 if (do_sigaltstack(&frame->uc.uc_stack, NULL,
214 regs->gprs[15]) == -EFAULT)
215 goto badframe;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700216 return regs->gprs[2];
217
218badframe:
219 force_sig(SIGSEGV, current);
220 return 0;
221}
222
223/*
224 * Set up a signal frame.
225 */
226
227
228/*
229 * Determine which stack to use..
230 */
231static inline void __user *
232get_sigframe(struct k_sigaction *ka, struct pt_regs * regs, size_t frame_size)
233{
234 unsigned long sp;
235
236 /* Default to using normal stack */
237 sp = regs->gprs[15];
238
Heiko Carstensde553432008-04-17 07:45:57 +0200239 /* Overflow on alternate signal stack gives SIGSEGV. */
240 if (on_sig_stack(sp) && !on_sig_stack((sp - frame_size) & -8UL))
241 return (void __user *) -1UL;
242
Linus Torvalds1da177e2005-04-16 15:20:36 -0700243 /* This is the X/Open sanctioned signal stack switching. */
244 if (ka->sa.sa_flags & SA_ONSTACK) {
245 if (! sas_ss_flags(sp))
246 sp = current->sas_ss_sp + current->sas_ss_size;
247 }
248
249 /* This is the legacy signal stack switching. */
250 else if (!user_mode(regs) &&
251 !(ka->sa.sa_flags & SA_RESTORER) &&
252 ka->sa.sa_restorer) {
253 sp = (unsigned long) ka->sa.sa_restorer;
254 }
255
256 return (void __user *)((sp - frame_size) & -8ul);
257}
258
259static inline int map_signal(int sig)
260{
261 if (current_thread_info()->exec_domain
262 && current_thread_info()->exec_domain->signal_invmap
263 && sig < 32)
264 return current_thread_info()->exec_domain->signal_invmap[sig];
265 else
266 return sig;
267}
268
Heiko Carstens54dfe5dd2006-02-01 03:06:38 -0800269static int setup_frame(int sig, struct k_sigaction *ka,
270 sigset_t *set, struct pt_regs * regs)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700271{
272 sigframe __user *frame;
273
274 frame = get_sigframe(ka, regs, sizeof(sigframe));
275 if (!access_ok(VERIFY_WRITE, frame, sizeof(sigframe)))
276 goto give_sigsegv;
277
Heiko Carstensde553432008-04-17 07:45:57 +0200278 if (frame == (void __user *) -1UL)
279 goto give_sigsegv;
280
Linus Torvalds1da177e2005-04-16 15:20:36 -0700281 if (__copy_to_user(&frame->sc.oldmask, &set->sig, _SIGMASK_COPY_SIZE))
282 goto give_sigsegv;
283
284 if (save_sigregs(regs, &frame->sregs))
285 goto give_sigsegv;
286 if (__put_user(&frame->sregs, &frame->sc.sregs))
287 goto give_sigsegv;
288
289 /* Set up to return from userspace. If provided, use a stub
290 already in userspace. */
291 if (ka->sa.sa_flags & SA_RESTORER) {
292 regs->gprs[14] = (unsigned long)
293 ka->sa.sa_restorer | PSW_ADDR_AMODE;
294 } else {
295 regs->gprs[14] = (unsigned long)
296 frame->retcode | PSW_ADDR_AMODE;
297 if (__put_user(S390_SYSCALL_OPCODE | __NR_sigreturn,
298 (u16 __user *)(frame->retcode)))
299 goto give_sigsegv;
300 }
301
302 /* Set up backchain. */
303 if (__put_user(regs->gprs[15], (addr_t __user *) frame))
304 goto give_sigsegv;
305
306 /* Set up registers for signal handler */
307 regs->gprs[15] = (unsigned long) frame;
308 regs->psw.addr = (unsigned long) ka->sa.sa_handler | PSW_ADDR_AMODE;
309
310 regs->gprs[2] = map_signal(sig);
311 regs->gprs[3] = (unsigned long) &frame->sc;
312
313 /* We forgot to include these in the sigcontext.
314 To avoid breaking binary compatibility, they are passed as args. */
315 regs->gprs[4] = current->thread.trap_no;
316 regs->gprs[5] = current->thread.prot_addr;
317
318 /* Place signal number on stack to allow backtrace from handler. */
319 if (__put_user(regs->gprs[2], (int __user *) &frame->signo))
320 goto give_sigsegv;
Heiko Carstens54dfe5dd2006-02-01 03:06:38 -0800321 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700322
323give_sigsegv:
324 force_sigsegv(sig, current);
Heiko Carstens54dfe5dd2006-02-01 03:06:38 -0800325 return -EFAULT;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700326}
327
Heiko Carstens54dfe5dd2006-02-01 03:06:38 -0800328static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700329 sigset_t *set, struct pt_regs * regs)
330{
331 int err = 0;
332 rt_sigframe __user *frame;
333
334 frame = get_sigframe(ka, regs, sizeof(rt_sigframe));
335 if (!access_ok(VERIFY_WRITE, frame, sizeof(rt_sigframe)))
336 goto give_sigsegv;
337
Heiko Carstensde553432008-04-17 07:45:57 +0200338 if (frame == (void __user *) -1UL)
339 goto give_sigsegv;
340
Linus Torvalds1da177e2005-04-16 15:20:36 -0700341 if (copy_siginfo_to_user(&frame->info, info))
342 goto give_sigsegv;
343
344 /* Create the ucontext. */
345 err |= __put_user(0, &frame->uc.uc_flags);
Al Viroc2814472005-09-29 00:16:02 +0100346 err |= __put_user(NULL, &frame->uc.uc_link);
347 err |= __put_user((void __user *)current->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700348 err |= __put_user(sas_ss_flags(regs->gprs[15]),
349 &frame->uc.uc_stack.ss_flags);
350 err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
351 err |= save_sigregs(regs, &frame->uc.uc_mcontext);
352 err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
353 if (err)
354 goto give_sigsegv;
355
356 /* Set up to return from userspace. If provided, use a stub
357 already in userspace. */
358 if (ka->sa.sa_flags & SA_RESTORER) {
359 regs->gprs[14] = (unsigned long)
360 ka->sa.sa_restorer | PSW_ADDR_AMODE;
361 } else {
362 regs->gprs[14] = (unsigned long)
363 frame->retcode | PSW_ADDR_AMODE;
Heiko Carstensb44df332006-05-01 12:16:15 -0700364 if (__put_user(S390_SYSCALL_OPCODE | __NR_rt_sigreturn,
365 (u16 __user *)(frame->retcode)))
366 goto give_sigsegv;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700367 }
368
369 /* Set up backchain. */
370 if (__put_user(regs->gprs[15], (addr_t __user *) frame))
371 goto give_sigsegv;
372
373 /* Set up registers for signal handler */
374 regs->gprs[15] = (unsigned long) frame;
375 regs->psw.addr = (unsigned long) ka->sa.sa_handler | PSW_ADDR_AMODE;
376
377 regs->gprs[2] = map_signal(sig);
378 regs->gprs[3] = (unsigned long) &frame->info;
379 regs->gprs[4] = (unsigned long) &frame->uc;
Heiko Carstens54dfe5dd2006-02-01 03:06:38 -0800380 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700381
382give_sigsegv:
383 force_sigsegv(sig, current);
Heiko Carstens54dfe5dd2006-02-01 03:06:38 -0800384 return -EFAULT;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700385}
386
387/*
388 * OK, we're invoking a handler
389 */
390
Heiko Carstens54dfe5dd2006-02-01 03:06:38 -0800391static int
Linus Torvalds1da177e2005-04-16 15:20:36 -0700392handle_signal(unsigned long sig, struct k_sigaction *ka,
393 siginfo_t *info, sigset_t *oldset, struct pt_regs * regs)
394{
Heiko Carstens54dfe5dd2006-02-01 03:06:38 -0800395 int ret;
396
Linus Torvalds1da177e2005-04-16 15:20:36 -0700397 /* Set up the stack frame */
398 if (ka->sa.sa_flags & SA_SIGINFO)
Heiko Carstens54dfe5dd2006-02-01 03:06:38 -0800399 ret = setup_rt_frame(sig, ka, info, oldset, regs);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700400 else
Heiko Carstens54dfe5dd2006-02-01 03:06:38 -0800401 ret = setup_frame(sig, ka, oldset, regs);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700402
Heiko Carstens54dfe5dd2006-02-01 03:06:38 -0800403 if (ret == 0) {
404 spin_lock_irq(&current->sighand->siglock);
405 sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
406 if (!(ka->sa.sa_flags & SA_NODEFER))
407 sigaddset(&current->blocked,sig);
408 recalc_sigpending();
409 spin_unlock_irq(&current->sighand->siglock);
410 }
411
412 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700413}
414
415/*
416 * Note that 'init' is a special process: it doesn't get signals it doesn't
417 * want to handle. Thus you cannot kill init even with a SIGKILL even by
418 * mistake.
419 *
420 * Note that we go through the signals twice: once to check the signals that
421 * the kernel can handle, and then we build all the user-level signal handling
422 * stack-frames in one go after that.
423 */
Heiko Carstens54dfe5dd2006-02-01 03:06:38 -0800424void do_signal(struct pt_regs *regs)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700425{
426 unsigned long retval = 0, continue_addr = 0, restart_addr = 0;
427 siginfo_t info;
428 int signr;
429 struct k_sigaction ka;
Heiko Carstens54dfe5dd2006-02-01 03:06:38 -0800430 sigset_t *oldset;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700431
432 /*
433 * We want the common case to go fast, which
434 * is why we may in certain cases get here from
435 * kernel mode. Just return without doing anything
436 * if so.
437 */
438 if (!user_mode(regs))
Heiko Carstens54dfe5dd2006-02-01 03:06:38 -0800439 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700440
Heiko Carstens54dfe5dd2006-02-01 03:06:38 -0800441 if (test_thread_flag(TIF_RESTORE_SIGMASK))
442 oldset = &current->saved_sigmask;
443 else
Linus Torvalds1da177e2005-04-16 15:20:36 -0700444 oldset = &current->blocked;
445
446 /* Are we from a system call? */
447 if (regs->trap == __LC_SVC_OLD_PSW) {
448 continue_addr = regs->psw.addr;
449 restart_addr = continue_addr - regs->ilc;
450 retval = regs->gprs[2];
451
452 /* Prepare for system call restart. We do this here so that a
453 debugger will see the already changed PSW. */
Heiko Carstens54dfe5dd2006-02-01 03:06:38 -0800454 switch (retval) {
455 case -ERESTARTNOHAND:
456 case -ERESTARTSYS:
457 case -ERESTARTNOINTR:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700458 regs->gprs[2] = regs->orig_gpr2;
459 regs->psw.addr = restart_addr;
Heiko Carstens54dfe5dd2006-02-01 03:06:38 -0800460 break;
461 case -ERESTART_RESTARTBLOCK:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700462 regs->gprs[2] = -EINTR;
463 }
Heiko Carstens84270822006-09-20 15:58:54 +0200464 regs->trap = -1; /* Don't deal with this again. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700465 }
466
467 /* Get signal to deliver. When running under ptrace, at this point
468 the debugger may change all our registers ... */
469 signr = get_signal_to_deliver(&info, &ka, regs, NULL);
470
471 /* Depending on the signal settings we may need to revert the
472 decision to restart the system call. */
473 if (signr > 0 && regs->psw.addr == restart_addr) {
474 if (retval == -ERESTARTNOHAND
475 || (retval == -ERESTARTSYS
476 && !(current->sighand->action[signr-1].sa.sa_flags
477 & SA_RESTART))) {
478 regs->gprs[2] = -EINTR;
479 regs->psw.addr = continue_addr;
480 }
481 }
482
483 if (signr > 0) {
484 /* Whee! Actually deliver the signal. */
Roland McGrath0ac30be2008-01-26 14:11:22 +0100485 int ret;
Martin Schwidefsky347a8dc2006-01-06 00:19:28 -0800486#ifdef CONFIG_COMPAT
Linus Torvalds1da177e2005-04-16 15:20:36 -0700487 if (test_thread_flag(TIF_31BIT)) {
Roland McGrath0ac30be2008-01-26 14:11:22 +0100488 ret = handle_signal32(signr, &ka, &info, oldset, regs);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700489 }
Roland McGrath0ac30be2008-01-26 14:11:22 +0100490 else
Linus Torvalds1da177e2005-04-16 15:20:36 -0700491#endif
Roland McGrath0ac30be2008-01-26 14:11:22 +0100492 ret = handle_signal(signr, &ka, &info, oldset, regs);
493 if (!ret) {
Heiko Carstens54dfe5dd2006-02-01 03:06:38 -0800494 /*
495 * A signal was successfully delivered; the saved
496 * sigmask will have been stored in the signal frame,
497 * and will be restored by sigreturn, so we can simply
498 * clear the TIF_RESTORE_SIGMASK flag.
499 */
500 if (test_thread_flag(TIF_RESTORE_SIGMASK))
501 clear_thread_flag(TIF_RESTORE_SIGMASK);
Roland McGrath0ac30be2008-01-26 14:11:22 +0100502
503 /*
504 * If we would have taken a single-step trap
505 * for a normal instruction, act like we took
506 * one for the handler setup.
507 */
508 if (current->thread.per_info.single_step)
509 set_thread_flag(TIF_SINGLE_STEP);
Heiko Carstens54dfe5dd2006-02-01 03:06:38 -0800510 }
511 return;
512 }
513
514 /*
515 * If there's no signal to deliver, we just put the saved sigmask back.
516 */
517 if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
518 clear_thread_flag(TIF_RESTORE_SIGMASK);
519 sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700520 }
521
522 /* Restart a different system call. */
523 if (retval == -ERESTART_RESTARTBLOCK
524 && regs->psw.addr == continue_addr) {
525 regs->gprs[2] = __NR_restart_syscall;
526 set_thread_flag(TIF_RESTART_SVC);
527 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700528}