2 * Common signal handling code for both 32 and 64 bits
4 * Copyright (c) 2007 Benjamin Herrenschmidt, IBM Coproration
5 * Extracted from signal_32.c and signal_64.c
7 * This file is subject to the terms and conditions of the GNU General
8 * Public License. See the file README.legal in the main directory of
9 * this archive for more details.
12 #include <linux/ptrace.h>
13 #include <linux/signal.h>
14 #include <asm/uaccess.h>
15 #include <asm/unistd.h>
19 /* Log an error when sending an unhandled signal to a process. Controlled
20 * through debug.exception-trace sysctl.
23 int show_unhandled_signals
= 0;
26 * Allocate space for the signal frame
28 void __user
* get_sigframe(struct k_sigaction
*ka
, struct pt_regs
*regs
,
31 unsigned long oldsp
, newsp
;
33 /* Default to using normal stack */
36 /* Check for alt stack */
37 if ((ka
->sa
.sa_flags
& SA_ONSTACK
) &&
38 current
->sas_ss_size
&& !on_sig_stack(oldsp
))
39 oldsp
= (current
->sas_ss_sp
+ current
->sas_ss_size
);
41 /* Get aligned frame */
42 newsp
= (oldsp
- frame_size
) & ~0xFUL
;
45 if (!access_ok(VERIFY_WRITE
, (void __user
*)newsp
, oldsp
- newsp
))
48 return (void __user
*)newsp
;
53 * Restore the user process's signal mask
55 void restore_sigmask(sigset_t
*set
)
57 sigdelsetmask(set
, ~_BLOCKABLE
);
58 spin_lock_irq(¤t
->sighand
->siglock
);
59 current
->blocked
= *set
;
61 spin_unlock_irq(¤t
->sighand
->siglock
);
64 static void check_syscall_restart(struct pt_regs
*regs
, struct k_sigaction
*ka
,
67 unsigned long ret
= regs
->gpr
[3];
71 if (TRAP(regs
) != 0x0C00)
74 /* error signalled ? */
75 if (!(regs
->ccr
& 0x10000000))
79 case ERESTART_RESTARTBLOCK
:
81 /* ERESTARTNOHAND means that the syscall should only be
82 * restarted if there was no handler for the signal, and since
83 * we only get here if there is a handler, we dont restart.
85 restart
= !has_handler
;
88 /* ERESTARTSYS means to restart the syscall if there is no
89 * handler or the handler was registered with SA_RESTART
91 restart
= !has_handler
|| (ka
->sa
.sa_flags
& SA_RESTART
) != 0;
94 /* ERESTARTNOINTR means that the syscall should be
95 * called again after the signal handler returns.
102 if (ret
== ERESTART_RESTARTBLOCK
)
103 regs
->gpr
[0] = __NR_restart_syscall
;
105 regs
->gpr
[3] = regs
->orig_gpr3
;
109 regs
->result
= -EINTR
;
110 regs
->gpr
[3] = EINTR
;
111 regs
->ccr
|= 0x10000000;
115 int do_signal(sigset_t
*oldset
, struct pt_regs
*regs
)
119 struct k_sigaction ka
;
121 int is32
= is_32bit_task();
123 if (current_thread_info()->local_flags
& _TLF_RESTORE_SIGMASK
)
124 oldset
= ¤t
->saved_sigmask
;
126 oldset
= ¤t
->blocked
;
128 signr
= get_signal_to_deliver(&info
, &ka
, regs
, NULL
);
130 /* Is there any syscall restart business here ? */
131 check_syscall_restart(regs
, &ka
, signr
> 0);
134 struct thread_info
*ti
= current_thread_info();
135 /* No signal to deliver -- put the saved sigmask back */
136 if (ti
->local_flags
& _TLF_RESTORE_SIGMASK
) {
137 ti
->local_flags
&= ~_TLF_RESTORE_SIGMASK
;
138 sigprocmask(SIG_SETMASK
, ¤t
->saved_sigmask
, NULL
);
140 return 0; /* no signals delivered */
144 * Reenable the DABR before delivering the signal to
145 * user space. The DABR will have been cleared if it
146 * triggered inside the kernel.
148 if (current
->thread
.dabr
) {
149 set_dabr(current
->thread
.dabr
);
150 #if defined(CONFIG_BOOKE)
151 mtspr(SPRN_DBCR0
, current
->thread
.dbcr0
);
156 if (ka
.sa
.sa_flags
& SA_SIGINFO
)
157 ret
= handle_rt_signal32(signr
, &ka
, &info
, oldset
,
160 ret
= handle_signal32(signr
, &ka
, &info
, oldset
,
163 ret
= handle_rt_signal64(signr
, &ka
, &info
, oldset
, regs
);
167 spin_lock_irq(¤t
->sighand
->siglock
);
168 sigorsets(¤t
->blocked
, ¤t
->blocked
,
170 if (!(ka
.sa
.sa_flags
& SA_NODEFER
))
171 sigaddset(¤t
->blocked
, signr
);
173 spin_unlock_irq(¤t
->sighand
->siglock
);
176 * A signal was successfully delivered; the saved sigmask is in
177 * its frame, and we can clear the TLF_RESTORE_SIGMASK flag.
179 current_thread_info()->local_flags
&= ~_TLF_RESTORE_SIGMASK
;
185 long sys_sigaltstack(const stack_t __user
*uss
, stack_t __user
*uoss
,
186 unsigned long r5
, unsigned long r6
, unsigned long r7
,
187 unsigned long r8
, struct pt_regs
*regs
)
189 return do_sigaltstack(uss
, uoss
, regs
->gpr
[1]);