Merge branch 'linus' into release

Conflicts:
	drivers/acpi/debug.c

Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 358 insertions, 0 deletions

diff --git a/arch/tile/kernel/signal.c b/arch/tile/kernel/signal.c
new file mode 100644
index 00000000000..45b66a3c991
--- /dev/null
+++ b/arch/tile/kernel/signal.c
@@ -0,0 +1,358 @@
+/*
+ * Copyright (C) 1991, 1992  Linus Torvalds
+ * Copyright 2010 Tilera Corporation. All Rights Reserved.
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful, but
+ *   WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ *   NON INFRINGEMENT.  See the GNU General Public License for
+ *   more details.
+ */
+
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/smp_lock.h>
+#include <linux/kernel.h>
+#include <linux/signal.h>
+#include <linux/errno.h>
+#include <linux/wait.h>
+#include <linux/unistd.h>
+#include <linux/stddef.h>
+#include <linux/personality.h>
+#include <linux/suspend.h>
+#include <linux/ptrace.h>
+#include <linux/elf.h>
+#include <linux/compat.h>
+#include <linux/syscalls.h>
+#include <linux/uaccess.h>
+#include <asm/processor.h>
+#include <asm/ucontext.h>
+#include <asm/sigframe.h>
+#include <asm/syscalls.h>
+#include <arch/interrupts.h>
+
+#define DEBUG_SIG 0
+
+#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
+
+
+long _sys_sigaltstack(const stack_t __user *uss,
+		      stack_t __user *uoss, struct pt_regs *regs)
+{
+	return do_sigaltstack(uss, uoss, regs->sp);
+}
+
+
+/*
+ * Do a signal return; undo the signal stack.
+ */
+
+int restore_sigcontext(struct pt_regs *regs,
+		       struct sigcontext __user *sc, long *pr0)
+{
+	int err = 0;
+	int i;
+
+	/* Always make any pending restarted system calls return -EINTR */
+	current_thread_info()->restart_block.fn = do_no_restart_syscall;
+
+	for (i = 0; i < sizeof(struct pt_regs)/sizeof(long); ++i)
+		err |= __get_user(((long *)regs)[i],
+				  &((long __user *)(&sc->regs))[i]);
+
+	regs->faultnum = INT_SWINT_1_SIGRETURN;
+
+	err |= __get_user(*pr0, &sc->regs.regs[0]);
+	return err;
+}
+
+/* sigreturn() returns long since it restores r0 in the interrupted code. */
+long _sys_rt_sigreturn(struct pt_regs *regs)
+{
+	struct rt_sigframe __user *frame =
+		(struct rt_sigframe __user *)(regs->sp);
+	sigset_t set;
+	long r0;
+
+	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
+		goto badframe;
+	if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
+		goto badframe;
+
+	sigdelsetmask(&set, ~_BLOCKABLE);
+	spin_lock_irq(&current->sighand->siglock);
+	current->blocked = set;
+	recalc_sigpending();
+	spin_unlock_irq(&current->sighand->siglock);
+
+	if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &r0))
+		goto badframe;
+
+	if (do_sigaltstack(&frame->uc.uc_stack, NULL, regs->sp) == -EFAULT)
+		goto badframe;
+
+	return r0;
+
+badframe:
+	force_sig(SIGSEGV, current);
+	return 0;
+}
+
+/*
+ * Set up a signal frame.
+ */
+
+int setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs)
+{
+	int i, err = 0;
+
+	for (i = 0; i < sizeof(struct pt_regs)/sizeof(long); ++i)
+		err |= __put_user(((long *)regs)[i],
+				  &((long __user *)(&sc->regs))[i]);
+
+	return err;
+}
+
+/*
+ * Determine which stack to use..
+ */
+static inline void __user *get_sigframe(struct k_sigaction *ka,
+					struct pt_regs *regs,
+					size_t frame_size)
+{
+	unsigned long sp;
+
+	/* Default to using normal stack */
+	sp = regs->sp;
+
+	/*
+	 * If we are on the alternate signal stack and would overflow
+	 * it, don't.  Return an always-bogus address instead so we
+	 * will die with SIGSEGV.
+	 */
+	if (on_sig_stack(sp) && !likely(on_sig_stack(sp - frame_size)))
+		return (void __user __force *)-1UL;
+
+	/* This is the X/Open sanctioned signal stack switching.  */
+	if (ka->sa.sa_flags & SA_ONSTACK) {
+		if (sas_ss_flags(sp) == 0)
+			sp = current->sas_ss_sp + current->sas_ss_size;
+	}
+
+	sp -= frame_size;
+	/*
+	 * Align the stack pointer according to the TILE ABI,
+	 * i.e. so that on function entry (sp & 15) == 0.
+	 */
+	sp &= -16UL;
+	return (void __user *) sp;
+}
+
+static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
+			   sigset_t *set, struct pt_regs *regs)
+{
+	unsigned long restorer;
+	struct rt_sigframe __user *frame;
+	int err = 0;
+	int usig;
+
+	frame = get_sigframe(ka, regs, sizeof(*frame));
+
+	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
+		goto give_sigsegv;
+
+	usig = current_thread_info()->exec_domain
+		&& current_thread_info()->exec_domain->signal_invmap
+		&& sig < 32
+		? current_thread_info()->exec_domain->signal_invmap[sig]
+		: sig;
+
+	/* Always write at least the signal number for the stack backtracer. */
+	if (ka->sa.sa_flags & SA_SIGINFO) {
+		/* At sigreturn time, restore the callee-save registers too. */
+		err |= copy_siginfo_to_user(&frame->info, info);
+		regs->flags |= PT_FLAGS_RESTORE_REGS;
+	} else {
+		err |= __put_user(info->si_signo, &frame->info.si_signo);
+	}
+
+	/* Create the ucontext.  */
+	err |= __clear_user(&frame->save_area, sizeof(frame->save_area));
+	err |= __put_user(0, &frame->uc.uc_flags);
+	err |= __put_user(NULL, &frame->uc.uc_link);
+	err |= __put_user((void __user *)(current->sas_ss_sp),
+			  &frame->uc.uc_stack.ss_sp);
+	err |= __put_user(sas_ss_flags(regs->sp),
+			  &frame->uc.uc_stack.ss_flags);
+	err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
+	err |= setup_sigcontext(&frame->uc.uc_mcontext, regs);
+	err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
+	if (err)
+		goto give_sigsegv;
+
+	restorer = VDSO_BASE;
+	if (ka->sa.sa_flags & SA_RESTORER)
+		restorer = (unsigned long) ka->sa.sa_restorer;
+
+	/*
+	 * Set up registers for signal handler.
+	 * Registers that we don't modify keep the value they had from
+	 * user-space at the time we took the signal.
+	 */
+	regs->pc = (unsigned long) ka->sa.sa_handler;
+	regs->ex1 = PL_ICS_EX1(USER_PL, 1); /* set crit sec in handler */
+	regs->sp = (unsigned long) frame;
+	regs->lr = restorer;
+	regs->regs[0] = (unsigned long) usig;
+
+	if (ka->sa.sa_flags & SA_SIGINFO) {
+		/* Need extra arguments, so mark to restore caller-saves. */
+		regs->regs[1] = (unsigned long) &frame->info;
+		regs->regs[2] = (unsigned long) &frame->uc;
+		regs->flags |= PT_FLAGS_CALLER_SAVES;
+	}
+
+	/*
+	 * Notify any tracer that was single-stepping it.
+	 * The tracer may want to single-step inside the
+	 * handler too.
+	 */
+	if (test_thread_flag(TIF_SINGLESTEP))
+		ptrace_notify(SIGTRAP);
+
+	return 0;
+
+give_sigsegv:
+	force_sigsegv(sig, current);
+	return -EFAULT;
+}
+
+/*
+ * OK, we're invoking a handler
+ */
+
+static int handle_signal(unsigned long sig, siginfo_t *info,
+			 struct k_sigaction *ka, sigset_t *oldset,
+			 struct pt_regs *regs)
+{
+	int ret;
+
+
+	/* Are we from a system call? */
+	if (regs->faultnum == INT_SWINT_1) {
+		/* If so, check system call restarting.. */
+		switch (regs->regs[0]) {
+		case -ERESTART_RESTARTBLOCK:
+		case -ERESTARTNOHAND:
+			regs->regs[0] = -EINTR;
+			break;
+
+		case -ERESTARTSYS:
+			if (!(ka->sa.sa_flags & SA_RESTART)) {
+				regs->regs[0] = -EINTR;
+				break;
+			}
+			/* fallthrough */
+		case -ERESTARTNOINTR:
+			/* Reload caller-saves to restore r0..r5 and r10. */
+			regs->flags |= PT_FLAGS_CALLER_SAVES;
+			regs->regs[0] = regs->orig_r0;
+			regs->pc -= 8;
+		}
+	}
+
+	/* Set up the stack frame */
+#ifdef CONFIG_COMPAT
+	if (is_compat_task())
+		ret = compat_setup_rt_frame(sig, ka, info, oldset, regs);
+	else
+#endif
+		ret = setup_rt_frame(sig, ka, info, oldset, regs);
+	if (ret == 0) {
+		/* This code is only called from system calls or from
+		 * the work_pending path in the return-to-user code, and
+		 * either way we can re-enable interrupts unconditionally.
+		 */
+		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, sig);
+		recalc_sigpending();
+		spin_unlock_irq(&current->sighand->siglock);
+	}
+
+	return ret;
+}
+
+/*
+ * Note that 'init' is a special process: it doesn't get signals it doesn't
+ * want to handle. Thus you cannot kill init even with a SIGKILL even by
+ * mistake.
+ */
+void do_signal(struct pt_regs *regs)
+{
+	siginfo_t info;
+	int signr;
+	struct k_sigaction ka;
+	sigset_t *oldset;
+
+	/*
+	 * i386 will check if we're coming from kernel mode and bail out
+	 * here.  In my experience this just turns weird crashes into
+	 * weird spin-hangs.  But if we find a case where this seems
+	 * helpful, we can reinstate the check on "!user_mode(regs)".
+	 */
+
+	if (current_thread_info()->status & TS_RESTORE_SIGMASK)
+		oldset = &current->saved_sigmask;
+	else
+		oldset = &current->blocked;
+
+	signr = get_signal_to_deliver(&info, &ka, regs, NULL);
+	if (signr > 0) {
+		/* Whee! Actually deliver the signal.  */
+		if (handle_signal(signr, &info, &ka, oldset, regs) == 0) {
+			/*
+			 * A signal was successfully delivered; the saved
+			 * sigmask will have been stored in the signal frame,
+			 * and will be restored by sigreturn, so we can simply
+			 * clear the TS_RESTORE_SIGMASK flag.
+			 */
+			current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
+		}
+
+		return;
+	}
+
+	/* Did we come from a system call? */
+	if (regs->faultnum == INT_SWINT_1) {
+		/* Restart the system call - no handlers present */
+		switch (regs->regs[0]) {
+		case -ERESTARTNOHAND:
+		case -ERESTARTSYS:
+		case -ERESTARTNOINTR:
+			regs->flags |= PT_FLAGS_CALLER_SAVES;
+			regs->regs[0] = regs->orig_r0;
+			regs->pc -= 8;
+			break;
+
+		case -ERESTART_RESTARTBLOCK:
+			regs->flags |= PT_FLAGS_CALLER_SAVES;
+			regs->regs[TREG_SYSCALL_NR] = __NR_restart_syscall;
+			regs->pc -= 8;
+			break;
+		}
+	}
+
+	/* If there's no signal to deliver, just put the saved sigmask back. */
+	if (current_thread_info()->status & TS_RESTORE_SIGMASK) {
+		current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
+		sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
+	}
+}