]>
git.proxmox.com Git - mirror_ubuntu-artful-kernel.git/blob - arch/um/kernel/signal.c
2 * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
3 * Licensed under the GPL
6 #include "linux/stddef.h"
8 #include "linux/sched.h"
9 #include "linux/wait.h"
10 #include "linux/kernel.h"
11 #include "linux/smp_lock.h"
12 #include "linux/module.h"
13 #include "linux/slab.h"
14 #include "linux/tty.h"
15 #include "linux/binfmts.h"
16 #include "linux/ptrace.h"
17 #include "asm/signal.h"
18 #include "asm/uaccess.h"
19 #include "asm/unistd.h"
20 #include "user_util.h"
21 #include "asm/ucontext.h"
22 #include "kern_util.h"
23 #include "signal_kern.h"
25 #include "frame_kern.h"
26 #include "sigcontext.h"
29 EXPORT_SYMBOL(block_signals
);
30 EXPORT_SYMBOL(unblock_signals
);
32 #define _S(nr) (1<<((nr)-1))
34 #define _BLOCKABLE (~(_S(SIGKILL) | _S(SIGSTOP)))
37 * OK, we're invoking a handler
39 static int handle_signal(struct pt_regs
*regs
, unsigned long signr
,
40 struct k_sigaction
*ka
, siginfo_t
*info
,
46 /* Always make any pending restarted system calls return -EINTR */
47 current_thread_info()->restart_block
.fn
= do_no_restart_syscall
;
49 /* Did we come from a system call? */
50 if(PT_REGS_SYSCALL_NR(regs
) >= 0){
51 /* If so, check system call restarting.. */
52 switch(PT_REGS_SYSCALL_RET(regs
)){
53 case -ERESTART_RESTARTBLOCK
:
55 PT_REGS_SYSCALL_RET(regs
) = -EINTR
;
59 if (!(ka
->sa
.sa_flags
& SA_RESTART
)) {
60 PT_REGS_SYSCALL_RET(regs
) = -EINTR
;
65 PT_REGS_RESTART_SYSCALL(regs
);
66 PT_REGS_ORIG_SYSCALL(regs
) = PT_REGS_SYSCALL_NR(regs
);
71 sp
= PT_REGS_SP(regs
);
72 if((ka
->sa
.sa_flags
& SA_ONSTACK
) && (sas_ss_flags(sp
) == 0))
73 sp
= current
->sas_ss_sp
+ current
->sas_ss_size
;
75 #ifdef CONFIG_ARCH_HAS_SC_SIGNALS
76 if(!(ka
->sa
.sa_flags
& SA_SIGINFO
))
77 err
= setup_signal_stack_sc(sp
, signr
, ka
, regs
, oldset
);
80 err
= setup_signal_stack_si(sp
, signr
, ka
, regs
, info
, oldset
);
83 spin_lock_irq(¤t
->sighand
->siglock
);
84 current
->blocked
= *oldset
;
86 spin_unlock_irq(¤t
->sighand
->siglock
);
87 force_sigsegv(signr
, current
);
89 spin_lock_irq(¤t
->sighand
->siglock
);
90 sigorsets(¤t
->blocked
, ¤t
->blocked
,
92 if(!(ka
->sa
.sa_flags
& SA_NODEFER
))
93 sigaddset(¤t
->blocked
, signr
);
95 spin_unlock_irq(¤t
->sighand
->siglock
);
101 static int kern_do_signal(struct pt_regs
*regs
)
103 struct k_sigaction ka_copy
;
106 int sig
, handled_sig
= 0;
108 if (test_thread_flag(TIF_RESTORE_SIGMASK
))
109 oldset
= ¤t
->saved_sigmask
;
111 oldset
= ¤t
->blocked
;
113 while((sig
= get_signal_to_deliver(&info
, &ka_copy
, regs
, NULL
)) > 0){
115 /* Whee! Actually deliver the signal. */
116 if(!handle_signal(regs
, sig
, &ka_copy
, &info
, oldset
)){
117 /* a signal was successfully delivered; the saved
118 * sigmask will have been stored in the signal frame,
119 * and will be restored by sigreturn, so we can simply
120 * clear the TIF_RESTORE_SIGMASK flag */
121 if (test_thread_flag(TIF_RESTORE_SIGMASK
))
122 clear_thread_flag(TIF_RESTORE_SIGMASK
);
127 /* Did we come from a system call? */
128 if(!handled_sig
&& (PT_REGS_SYSCALL_NR(regs
) >= 0)){
129 /* Restart the system call - no handlers present */
130 switch(PT_REGS_SYSCALL_RET(regs
)){
131 case -ERESTARTNOHAND
:
133 case -ERESTARTNOINTR
:
134 PT_REGS_ORIG_SYSCALL(regs
) = PT_REGS_SYSCALL_NR(regs
);
135 PT_REGS_RESTART_SYSCALL(regs
);
137 case -ERESTART_RESTARTBLOCK
:
138 PT_REGS_ORIG_SYSCALL(regs
) = __NR_restart_syscall
;
139 PT_REGS_RESTART_SYSCALL(regs
);
144 /* This closes a way to execute a system call on the host. If
145 * you set a breakpoint on a system call instruction and singlestep
146 * from it, the tracing thread used to PTRACE_SINGLESTEP the process
147 * rather than PTRACE_SYSCALL it, allowing the system call to execute
148 * on the host. The tracing thread will check this flag and
149 * PTRACE_SYSCALL if necessary.
151 if(current
->ptrace
& PT_DTRACE
)
152 current
->thread
.singlestep_syscall
=
153 is_syscall(PT_REGS_IP(¤t
->thread
.regs
));
155 /* if there's no signal to deliver, we just put the saved sigmask
157 if (!handled_sig
&& test_thread_flag(TIF_RESTORE_SIGMASK
)) {
158 clear_thread_flag(TIF_RESTORE_SIGMASK
);
159 sigprocmask(SIG_SETMASK
, ¤t
->saved_sigmask
, NULL
);
166 return kern_do_signal(¤t
->thread
.regs
);
170 * Atomically swap in the new signal mask, and wait for a signal.
172 long sys_sigsuspend(int history0
, int history1
, old_sigset_t mask
)
175 spin_lock_irq(¤t
->sighand
->siglock
);
176 current
->saved_sigmask
= current
->blocked
;
177 siginitset(¤t
->blocked
, mask
);
179 spin_unlock_irq(¤t
->sighand
->siglock
);
181 current
->state
= TASK_INTERRUPTIBLE
;
183 set_thread_flag(TIF_RESTORE_SIGMASK
);
184 return -ERESTARTNOHAND
;
187 long sys_sigaltstack(const stack_t __user
*uss
, stack_t __user
*uoss
)
189 return do_sigaltstack(uss
, uoss
, PT_REGS_SP(¤t
->thread
.regs
));