1 files changed, 426 insertions, 0 deletions

diff --git a/kernel/arch/frv/kernel/signal.c b/kernel/arch/frv/kernel/signal.c
new file mode 100644
index 000000000..82d5e914d
--- /dev/null
+++ b/kernel/arch/frv/kernel/signal.c
@@ -0,0 +1,426 @@
+/* signal.c: FRV specific bits of signal handling
+ *
+ * Copyright (C) 2003-5 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ * - Derived from arch/m68k/kernel/signal.c
+ *
+ * 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; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/kernel.h>
+#include <linux/signal.h>
+#include <linux/errno.h>
+#include <linux/wait.h>
+#include <linux/ptrace.h>
+#include <linux/unistd.h>
+#include <linux/personality.h>
+#include <linux/tracehook.h>
+#include <asm/ucontext.h>
+#include <asm/uaccess.h>
+#include <asm/cacheflush.h>
+
+#define DEBUG_SIG 0
+
+struct fdpic_func_descriptor {
+	unsigned long	text;
+	unsigned long	GOT;
+};
+
+/*
+ * Do a signal return; undo the signal stack.
+ */
+
+struct sigframe
+{
+	__sigrestore_t pretcode;
+	int sig;
+	struct sigcontext sc;
+	unsigned long extramask[_NSIG_WORDS-1];
+	uint32_t retcode[2];
+};
+
+struct rt_sigframe
+{
+	__sigrestore_t pretcode;
+	int sig;
+	struct siginfo __user *pinfo;
+	void __user *puc;
+	struct siginfo info;
+	struct ucontext uc;
+	uint32_t retcode[2];
+};
+
+static int restore_sigcontext(struct sigcontext __user *sc, int *_gr8)
+{
+	struct user_context *user = current->thread.user;
+	unsigned long tbr, psr;
+
+	/* Always make any pending restarted system calls return -EINTR */
+	current->restart_block.fn = do_no_restart_syscall;
+
+	tbr = user->i.tbr;
+	psr = user->i.psr;
+	if (copy_from_user(user, &sc->sc_context, sizeof(sc->sc_context)))
+		goto badframe;
+	user->i.tbr = tbr;
+	user->i.psr = psr;
+
+	restore_user_regs(user);
+
+	user->i.syscallno = -1;		/* disable syscall checks */
+
+	*_gr8 = user->i.gr[8];
+	return 0;
+
+ badframe:
+	return 1;
+}
+
+asmlinkage int sys_sigreturn(void)
+{
+	struct sigframe __user *frame = (struct sigframe __user *) __frame->sp;
+	sigset_t set;
+	int gr8;
+
+	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
+		goto badframe;
+	if (__get_user(set.sig[0], &frame->sc.sc_oldmask))
+		goto badframe;
+
+	if (_NSIG_WORDS > 1 &&
+	    __copy_from_user(&set.sig[1], &frame->extramask, sizeof(frame->extramask)))
+		goto badframe;
+
+	set_current_blocked(&set);
+
+	if (restore_sigcontext(&frame->sc, &gr8))
+		goto badframe;
+	return gr8;
+
+ badframe:
+	force_sig(SIGSEGV, current);
+	return 0;
+}
+
+asmlinkage int sys_rt_sigreturn(void)
+{
+	struct rt_sigframe __user *frame = (struct rt_sigframe __user *) __frame->sp;
+	sigset_t set;
+	int gr8;
+
+	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
+		goto badframe;
+	if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
+		goto badframe;
+
+	set_current_blocked(&set);
+
+	if (restore_sigcontext(&frame->uc.uc_mcontext, &gr8))
+		goto badframe;
+
+	if (restore_altstack(&frame->uc.uc_stack))
+		goto badframe;
+
+	return gr8;
+
+badframe:
+	force_sig(SIGSEGV, current);
+	return 0;
+}
+
+/*
+ * Set up a signal frame
+ */
+static int setup_sigcontext(struct sigcontext __user *sc, unsigned long mask)
+{
+	save_user_regs(current->thread.user);
+
+	if (copy_to_user(&sc->sc_context, current->thread.user, sizeof(sc->sc_context)) != 0)
+		goto badframe;
+
+	/* non-iBCS2 extensions.. */
+	if (__put_user(mask, &sc->sc_oldmask) < 0)
+		goto badframe;
+
+	return 0;
+
+ badframe:
+	return 1;
+}
+
+/*****************************************************************************/
+/*
+ * Determine which stack to use..
+ */
+static inline void __user *get_sigframe(struct ksignal *ksig,
+					size_t frame_size)
+{
+	unsigned long sp = sigsp(__frame->sp, ksig);
+
+	return (void __user *) ((sp - frame_size) & ~7UL);
+
+} /* end get_sigframe() */
+
+/*****************************************************************************/
+/*
+ *
+ */
+static int setup_frame(struct ksignal *ksig, sigset_t *set)
+{
+	struct sigframe __user *frame;
+	int sig = ksig->sig;
+
+	frame = get_sigframe(ksig, sizeof(*frame));
+
+	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
+		return -EFAULT;
+
+	if (__put_user(sig, &frame->sig) < 0)
+		return -EFAULT;
+
+	if (setup_sigcontext(&frame->sc, set->sig[0]))
+		return -EFAULT;
+
+	if (_NSIG_WORDS > 1) {
+		if (__copy_to_user(frame->extramask, &set->sig[1],
+				   sizeof(frame->extramask)))
+			return -EFAULT;
+	}
+
+	/* Set up to return from userspace.  If provided, use a stub
+	 * already in userspace.  */
+	if (ksig->ka.sa.sa_flags & SA_RESTORER) {
+		if (__put_user(ksig->ka.sa.sa_restorer, &frame->pretcode) < 0)
+			return -EFAULT;
+	}
+	else {
+		/* Set up the following code on the stack:
+		 *	setlos	#__NR_sigreturn,gr7
+		 *	tira	gr0,0
+		 */
+		if (__put_user((__sigrestore_t)frame->retcode, &frame->pretcode) ||
+		    __put_user(0x8efc0000|__NR_sigreturn, &frame->retcode[0]) ||
+		    __put_user(0xc0700000, &frame->retcode[1]))
+			return -EFAULT;
+
+		flush_icache_range((unsigned long) frame->retcode,
+				   (unsigned long) (frame->retcode + 2));
+	}
+
+	/* Set up registers for the signal handler */
+	if (current->personality & FDPIC_FUNCPTRS) {
+		struct fdpic_func_descriptor __user *funcptr =
+			(struct fdpic_func_descriptor __user *) ksig->ka.sa.sa_handler;
+		struct fdpic_func_descriptor desc;
+		if (copy_from_user(&desc, funcptr, sizeof(desc)))
+			return -EFAULT;
+		__frame->pc = desc.text;
+		__frame->gr15 = desc.GOT;
+	} else {
+		__frame->pc   = (unsigned long) ksig->ka.sa.sa_handler;
+		__frame->gr15 = 0;
+	}
+
+	__frame->sp   = (unsigned long) frame;
+	__frame->lr   = (unsigned long) &frame->retcode;
+	__frame->gr8  = sig;
+
+#if DEBUG_SIG
+	printk("SIG deliver %d (%s:%d): sp=%p pc=%lx ra=%p\n",
+	       sig, current->comm, current->pid, frame, __frame->pc,
+	       frame->pretcode);
+#endif
+
+	return 0;
+} /* end setup_frame() */
+
+/*****************************************************************************/
+/*
+ *
+ */
+static int setup_rt_frame(struct ksignal *ksig, sigset_t *set)
+{
+	struct rt_sigframe __user *frame;
+	int sig = ksig->sig;
+
+	frame = get_sigframe(ksig, sizeof(*frame));
+
+	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
+		return -EFAULT;
+
+	if (__put_user(sig,		&frame->sig) ||
+	    __put_user(&frame->info,	&frame->pinfo) ||
+	    __put_user(&frame->uc,	&frame->puc))
+		return -EFAULT;
+
+	if (copy_siginfo_to_user(&frame->info, &ksig->info))
+		return -EFAULT;
+
+	/* Create the ucontext.  */
+	if (__put_user(0, &frame->uc.uc_flags) ||
+	    __put_user(NULL, &frame->uc.uc_link) ||
+	    __save_altstack(&frame->uc.uc_stack, __frame->sp))
+		return -EFAULT;
+
+	if (setup_sigcontext(&frame->uc.uc_mcontext, set->sig[0]))
+		return -EFAULT;
+
+	if (__copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)))
+		return -EFAULT;
+
+	/* Set up to return from userspace.  If provided, use a stub
+	 * already in userspace.  */
+	if (ksig->ka.sa.sa_flags & SA_RESTORER) {
+		if (__put_user(ksig->ka.sa.sa_restorer, &frame->pretcode))
+			return -EFAULT;
+	}
+	else {
+		/* Set up the following code on the stack:
+		 *	setlos	#__NR_sigreturn,gr7
+		 *	tira	gr0,0
+		 */
+		if (__put_user((__sigrestore_t)frame->retcode, &frame->pretcode) ||
+		    __put_user(0x8efc0000|__NR_rt_sigreturn, &frame->retcode[0]) ||
+		    __put_user(0xc0700000, &frame->retcode[1]))
+			return -EFAULT;
+
+		flush_icache_range((unsigned long) frame->retcode,
+				   (unsigned long) (frame->retcode + 2));
+	}
+
+	/* Set up registers for signal handler */
+	if (current->personality & FDPIC_FUNCPTRS) {
+		struct fdpic_func_descriptor __user *funcptr =
+			(struct fdpic_func_descriptor __user *) ksig->ka.sa.sa_handler;
+		struct fdpic_func_descriptor desc;
+		if (copy_from_user(&desc, funcptr, sizeof(desc)))
+			return -EFAULT;
+		__frame->pc = desc.text;
+		__frame->gr15 = desc.GOT;
+	} else {
+		__frame->pc   = (unsigned long) ksig->ka.sa.sa_handler;
+		__frame->gr15 = 0;
+	}
+
+	__frame->sp  = (unsigned long) frame;
+	__frame->lr  = (unsigned long) &frame->retcode;
+	__frame->gr8 = sig;
+	__frame->gr9 = (unsigned long) &frame->info;
+
+#if DEBUG_SIG
+	printk("SIG deliver %d (%s:%d): sp=%p pc=%lx ra=%p\n",
+	       sig, current->comm, current->pid, frame, __frame->pc,
+	       frame->pretcode);
+#endif
+	return 0;
+
+} /* end setup_rt_frame() */
+
+/*****************************************************************************/
+/*
+ * OK, we're invoking a handler
+ */
+static void handle_signal(struct ksignal *ksig)
+{
+	sigset_t *oldset = sigmask_to_save();
+	int ret;
+
+	/* Are we from a system call? */
+	if (__frame->syscallno != -1) {
+		/* If so, check system call restarting.. */
+		switch (__frame->gr8) {
+		case -ERESTART_RESTARTBLOCK:
+		case -ERESTARTNOHAND:
+			__frame->gr8 = -EINTR;
+			break;
+
+		case -ERESTARTSYS:
+			if (!(ksig->ka.sa.sa_flags & SA_RESTART)) {
+				__frame->gr8 = -EINTR;
+				break;
+			}
+
+			/* fallthrough */
+		case -ERESTARTNOINTR:
+			__frame->gr8 = __frame->orig_gr8;
+			__frame->pc -= 4;
+		}
+		__frame->syscallno = -1;
+	}
+
+	/* Set up the stack frame */
+	if (ksig->ka.sa.sa_flags & SA_SIGINFO)
+		ret = setup_rt_frame(ksig, oldset);
+	else
+		ret = setup_frame(ksig, oldset);
+
+	signal_setup_done(ret, ksig, test_thread_flag(TIF_SINGLESTEP));
+} /* end handle_signal() */
+
+/*****************************************************************************/
+/*
+ * 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.
+ */
+static void do_signal(void)
+{
+	struct ksignal ksig;
+
+	if (get_signal(&ksig)) {
+		handle_signal(&ksig);
+		return;
+	}
+
+	/* Did we come from a system call? */
+	if (__frame->syscallno != -1) {
+		/* Restart the system call - no handlers present */
+		switch (__frame->gr8) {
+		case -ERESTARTNOHAND:
+		case -ERESTARTSYS:
+		case -ERESTARTNOINTR:
+			__frame->gr8 = __frame->orig_gr8;
+			__frame->pc -= 4;
+			break;
+
+		case -ERESTART_RESTARTBLOCK:
+			__frame->gr7 = __NR_restart_syscall;
+			__frame->pc -= 4;
+			break;
+		}
+		__frame->syscallno = -1;
+	}
+
+	/* if there's no signal to deliver, we just put the saved sigmask
+	 * back */
+	restore_saved_sigmask();
+} /* end do_signal() */
+
+/*****************************************************************************/
+/*
+ * notification of userspace execution resumption
+ * - triggered by the TIF_WORK_MASK flags
+ */
+asmlinkage void do_notify_resume(__u32 thread_info_flags)
+{
+	/* pending single-step? */
+	if (thread_info_flags & _TIF_SINGLESTEP)
+		clear_thread_flag(TIF_SINGLESTEP);
+
+	/* deal with pending signal delivery */
+	if (thread_info_flags & _TIF_SIGPENDING)
+		do_signal();
+
+	/* deal with notification on about to resume userspace execution */
+	if (thread_info_flags & _TIF_NOTIFY_RESUME) {
+		clear_thread_flag(TIF_NOTIFY_RESUME);
+		tracehook_notify_resume(__frame);
+	}
+
+} /* end do_notify_resume() */