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-rw-r--r--arch/powerpc/kernel/signal.c180
1 files changed, 180 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/signal.c b/arch/powerpc/kernel/signal.c
new file mode 100644
index 000000000000..c434d6c4e4e6
--- /dev/null
+++ b/arch/powerpc/kernel/signal.c
@@ -0,0 +1,180 @@
+/*
+ * Common signal handling code for both 32 and 64 bits
+ *
+ * Copyright (c) 2007 Benjamin Herrenschmidt, IBM Coproration
+ * Extracted from signal_32.c and signal_64.c
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License. See the file README.legal in the main directory of
+ * this archive for more details.
+ */
+
+#include <linux/ptrace.h>
+#include <linux/signal.h>
+#include <asm/uaccess.h>
+#include <asm/unistd.h>
+
+#include "signal.h"
+
+/*
+ * Allocate space for the signal frame
+ */
+void __user * get_sigframe(struct k_sigaction *ka, struct pt_regs *regs,
+ size_t frame_size)
+{
+ unsigned long oldsp, newsp;
+
+ /* Default to using normal stack */
+ oldsp = regs->gpr[1];
+
+ /* Check for alt stack */
+ if ((ka->sa.sa_flags & SA_ONSTACK) &&
+ current->sas_ss_size && !on_sig_stack(oldsp))
+ oldsp = (current->sas_ss_sp + current->sas_ss_size);
+
+ /* Get aligned frame */
+ newsp = (oldsp - frame_size) & ~0xFUL;
+
+ /* Check access */
+ if (!access_ok(VERIFY_WRITE, (void __user *)newsp, oldsp - newsp))
+ return NULL;
+
+ return (void __user *)newsp;
+}
+
+
+/*
+ * Restore the user process's signal mask
+ */
+void restore_sigmask(sigset_t *set)
+{
+ sigdelsetmask(set, ~_BLOCKABLE);
+ spin_lock_irq(&current->sighand->siglock);
+ current->blocked = *set;
+ recalc_sigpending();
+ spin_unlock_irq(&current->sighand->siglock);
+}
+
+static void check_syscall_restart(struct pt_regs *regs, struct k_sigaction *ka,
+ int has_handler)
+{
+ unsigned long ret = regs->gpr[3];
+ int restart = 1;
+
+ /* syscall ? */
+ if (TRAP(regs) != 0x0C00)
+ return;
+
+ /* error signalled ? */
+ if (!(regs->ccr & 0x10000000))
+ return;
+
+ switch (ret) {
+ case ERESTART_RESTARTBLOCK:
+ case ERESTARTNOHAND:
+ /* ERESTARTNOHAND means that the syscall should only be
+ * restarted if there was no handler for the signal, and since
+ * we only get here if there is a handler, we dont restart.
+ */
+ restart = !has_handler;
+ break;
+ case ERESTARTSYS:
+ /* ERESTARTSYS means to restart the syscall if there is no
+ * handler or the handler was registered with SA_RESTART
+ */
+ restart = !has_handler || (ka->sa.sa_flags & SA_RESTART) != 0;
+ break;
+ case ERESTARTNOINTR:
+ /* ERESTARTNOINTR means that the syscall should be
+ * called again after the signal handler returns.
+ */
+ break;
+ default:
+ return;
+ }
+ if (restart) {
+ if (ret == ERESTART_RESTARTBLOCK)
+ regs->gpr[0] = __NR_restart_syscall;
+ else
+ regs->gpr[3] = regs->orig_gpr3;
+ regs->nip -= 4;
+ regs->result = 0;
+ } else {
+ regs->result = -EINTR;
+ regs->gpr[3] = EINTR;
+ regs->ccr |= 0x10000000;
+ }
+}
+
+int do_signal(sigset_t *oldset, struct pt_regs *regs)
+{
+ siginfo_t info;
+ int signr;
+ struct k_sigaction ka;
+ int ret;
+ int is32 = is_32bit_task();
+
+ if (test_thread_flag(TIF_RESTORE_SIGMASK))
+ oldset = &current->saved_sigmask;
+ else if (!oldset)
+ oldset = &current->blocked;
+
+ signr = get_signal_to_deliver(&info, &ka, regs, NULL);
+
+ /* Is there any syscall restart business here ? */
+ check_syscall_restart(regs, &ka, signr > 0);
+
+ if (signr <= 0) {
+ /* No signal to deliver -- put the saved sigmask back */
+ if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
+ clear_thread_flag(TIF_RESTORE_SIGMASK);
+ sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
+ }
+ return 0; /* no signals delivered */
+ }
+
+ /*
+ * Reenable the DABR before delivering the signal to
+ * user space. The DABR will have been cleared if it
+ * triggered inside the kernel.
+ */
+ if (current->thread.dabr)
+ set_dabr(current->thread.dabr);
+
+ if (is32) {
+ if (ka.sa.sa_flags & SA_SIGINFO)
+ ret = handle_rt_signal32(signr, &ka, &info, oldset,
+ regs);
+ else
+ ret = handle_signal32(signr, &ka, &info, oldset,
+ regs);
+ } else {
+ ret = handle_rt_signal64(signr, &ka, &info, oldset, regs);
+ }
+
+ if (ret) {
+ spin_lock_irq(&current->sighand->siglock);
+ sigorsets(&current->blocked, &current->blocked,
+ &ka.sa.sa_mask);
+ if (!(ka.sa.sa_flags & SA_NODEFER))
+ sigaddset(&current->blocked, signr);
+ recalc_sigpending();
+ spin_unlock_irq(&current->sighand->siglock);
+
+ /*
+ * A signal was successfully delivered; the saved sigmask is in
+ * its frame, and we can clear the TIF_RESTORE_SIGMASK flag.
+ */
+ if (test_thread_flag(TIF_RESTORE_SIGMASK))
+ clear_thread_flag(TIF_RESTORE_SIGMASK);
+ }
+
+ return ret;
+}
+
+long sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss,
+ unsigned long r5, unsigned long r6, unsigned long r7,
+ unsigned long r8, struct pt_regs *regs)
+{
+ return do_sigaltstack(uss, uoss, regs->gpr[1]);
+}