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]);