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>
20 * Allocate space for the signal frame
22 void __user
* get_sigframe(struct k_sigaction
*ka
, struct pt_regs
*regs
,
25 unsigned long oldsp
, newsp
;
27 /* Default to using normal stack */
30 /* Check for alt stack */
31 if ((ka
->sa
.sa_flags
& SA_ONSTACK
) &&
32 current
->sas_ss_size
&& !on_sig_stack(oldsp
))
33 oldsp
= (current
->sas_ss_sp
+ current
->sas_ss_size
);
35 /* Get aligned frame */
36 newsp
= (oldsp
- frame_size
) & ~0xFUL
;
39 if (!access_ok(VERIFY_WRITE
, (void __user
*)newsp
, oldsp
- newsp
))
42 return (void __user
*)newsp
;
47 * Restore the user process's signal mask
49 void restore_sigmask(sigset_t
*set
)
51 sigdelsetmask(set
, ~_BLOCKABLE
);
52 spin_lock_irq(¤t
->sighand
->siglock
);
53 current
->blocked
= *set
;
55 spin_unlock_irq(¤t
->sighand
->siglock
);
58 static void check_syscall_restart(struct pt_regs
*regs
, struct k_sigaction
*ka
,
61 unsigned long ret
= regs
->gpr
[3];
65 if (TRAP(regs
) != 0x0C00)
68 /* error signalled ? */
69 if (!(regs
->ccr
& 0x10000000))
73 case ERESTART_RESTARTBLOCK
:
75 /* ERESTARTNOHAND means that the syscall should only be
76 * restarted if there was no handler for the signal, and since
77 * we only get here if there is a handler, we dont restart.
79 restart
= !has_handler
;
82 /* ERESTARTSYS means to restart the syscall if there is no
83 * handler or the handler was registered with SA_RESTART
85 restart
= !has_handler
|| (ka
->sa
.sa_flags
& SA_RESTART
) != 0;
88 /* ERESTARTNOINTR means that the syscall should be
89 * called again after the signal handler returns.
96 if (ret
== ERESTART_RESTARTBLOCK
)
97 regs
->gpr
[0] = __NR_restart_syscall
;
99 regs
->gpr
[3] = regs
->orig_gpr3
;
103 regs
->result
= -EINTR
;
104 regs
->gpr
[3] = EINTR
;
105 regs
->ccr
|= 0x10000000;
109 int do_signal(sigset_t
*oldset
, struct pt_regs
*regs
)
113 struct k_sigaction ka
;
115 int is32
= is_32bit_task();
117 if (test_thread_flag(TIF_RESTORE_SIGMASK
))
118 oldset
= ¤t
->saved_sigmask
;
120 oldset
= ¤t
->blocked
;
122 signr
= get_signal_to_deliver(&info
, &ka
, regs
, NULL
);
124 /* Is there any syscall restart business here ? */
125 check_syscall_restart(regs
, &ka
, signr
> 0);
128 /* No signal to deliver -- put the saved sigmask back */
129 if (test_thread_flag(TIF_RESTORE_SIGMASK
)) {
130 clear_thread_flag(TIF_RESTORE_SIGMASK
);
131 sigprocmask(SIG_SETMASK
, ¤t
->saved_sigmask
, NULL
);
133 return 0; /* no signals delivered */
137 * Reenable the DABR before delivering the signal to
138 * user space. The DABR will have been cleared if it
139 * triggered inside the kernel.
141 if (current
->thread
.dabr
)
142 set_dabr(current
->thread
.dabr
);
145 if (ka
.sa
.sa_flags
& SA_SIGINFO
)
146 ret
= handle_rt_signal32(signr
, &ka
, &info
, oldset
,
149 ret
= handle_signal32(signr
, &ka
, &info
, oldset
,
152 ret
= handle_rt_signal64(signr
, &ka
, &info
, oldset
, regs
);
156 spin_lock_irq(¤t
->sighand
->siglock
);
157 sigorsets(¤t
->blocked
, ¤t
->blocked
,
159 if (!(ka
.sa
.sa_flags
& SA_NODEFER
))
160 sigaddset(¤t
->blocked
, signr
);
162 spin_unlock_irq(¤t
->sighand
->siglock
);
165 * A signal was successfully delivered; the saved sigmask is in
166 * its frame, and we can clear the TIF_RESTORE_SIGMASK flag.
168 if (test_thread_flag(TIF_RESTORE_SIGMASK
))
169 clear_thread_flag(TIF_RESTORE_SIGMASK
);
175 long sys_sigaltstack(const stack_t __user
*uss
, stack_t __user
*uoss
,
176 unsigned long r5
, unsigned long r6
, unsigned long r7
,
177 unsigned long r8
, struct pt_regs
*regs
)
179 return do_sigaltstack(uss
, uoss
, regs
->gpr
[1]);