Merge branch 'linux-2.6'

1 files changed, 356 insertions, 0 deletions

diff --git a/arch/blackfin/kernel/signal.c b/arch/blackfin/kernel/signal.c
new file mode 100644
index 00000000000..316e65c3439
--- /dev/null
+++ b/arch/blackfin/kernel/signal.c
@@ -0,0 +1,356 @@
+/*
+ * File:         arch/blackfin/kernel/signal.c
+ * Based on:
+ * Author:
+ *
+ * Created:
+ * Description:
+ *
+ * Modified:
+ *               Copyright 2004-2006 Analog Devices Inc.
+ *
+ * Bugs:         Enter bugs at http://blackfin.uclinux.org/
+ *
+ * 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.
+ *
+ * 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.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see the file COPYING, or write
+ * to the Free Software Foundation, Inc.,
+ * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#include <linux/signal.h>
+#include <linux/syscalls.h>
+#include <linux/ptrace.h>
+#include <linux/tty.h>
+#include <linux/personality.h>
+#include <linux/binfmts.h>
+#include <linux/freezer.h>
+
+#include <asm/uaccess.h>
+#include <asm/cacheflush.h>
+#include <asm/ucontext.h>
+
+#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
+
+struct fdpic_func_descriptor {
+	unsigned long	text;
+	unsigned long	GOT;
+};
+
+struct rt_sigframe {
+	int sig;
+	struct siginfo *pinfo;
+	void *puc;
+	char retcode[8];
+	struct siginfo info;
+	struct ucontext uc;
+};
+
+asmlinkage int sys_sigaltstack(const stack_t * uss, stack_t * uoss)
+{
+	return do_sigaltstack(uss, uoss, rdusp());
+}
+
+static inline int
+rt_restore_sigcontext(struct pt_regs *regs, struct sigcontext *sc, int *pr0)
+{
+	unsigned long usp = 0;
+	int err = 0;
+
+#define RESTORE(x) err |= __get_user(regs->x, &sc->sc_##x)
+
+	/* restore passed registers */
+	RESTORE(r0); RESTORE(r1); RESTORE(r2); RESTORE(r3);
+	RESTORE(r4); RESTORE(r5); RESTORE(r6); RESTORE(r7);
+	RESTORE(p0); RESTORE(p1); RESTORE(p2); RESTORE(p3);
+	RESTORE(p4); RESTORE(p5);
+	err |= __get_user(usp, &sc->sc_usp);
+	wrusp(usp);
+	RESTORE(a0w); RESTORE(a1w);
+	RESTORE(a0x); RESTORE(a1x);
+	RESTORE(astat);
+	RESTORE(rets);
+	RESTORE(pc);
+	RESTORE(retx);
+	RESTORE(fp);
+	RESTORE(i0); RESTORE(i1); RESTORE(i2); RESTORE(i3);
+	RESTORE(m0); RESTORE(m1); RESTORE(m2); RESTORE(m3);
+	RESTORE(l0); RESTORE(l1); RESTORE(l2); RESTORE(l3);
+	RESTORE(b0); RESTORE(b1); RESTORE(b2); RESTORE(b3);
+	RESTORE(lc0); RESTORE(lc1);
+	RESTORE(lt0); RESTORE(lt1);
+	RESTORE(lb0); RESTORE(lb1);
+	RESTORE(seqstat);
+
+	regs->orig_p0 = -1;	/* disable syscall checks */
+
+	*pr0 = regs->r0;
+	return err;
+}
+
+asmlinkage int do_rt_sigreturn(unsigned long __unused)
+{
+	struct pt_regs *regs = (struct pt_regs *)__unused;
+	unsigned long usp = rdusp();
+	struct rt_sigframe *frame = (struct rt_sigframe *)(usp);
+	sigset_t set;
+	int 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 (rt_restore_sigcontext(regs, &frame->uc.uc_mcontext, &r0))
+		goto badframe;
+
+	if (do_sigaltstack(&frame->uc.uc_stack, NULL, regs->usp) == -EFAULT)
+		goto badframe;
+
+	return r0;
+
+      badframe:
+	force_sig(SIGSEGV, current);
+	return 0;
+}
+
+static inline int rt_setup_sigcontext(struct sigcontext *sc, struct pt_regs *regs)
+{
+	int err = 0;
+
+#define SETUP(x) err |= __put_user(regs->x, &sc->sc_##x)
+
+	SETUP(r0); SETUP(r1); SETUP(r2); SETUP(r3);
+	SETUP(r4); SETUP(r5); SETUP(r6); SETUP(r7);
+	SETUP(p0); SETUP(p1); SETUP(p2); SETUP(p3);
+	SETUP(p4); SETUP(p5);
+	err |= __put_user(rdusp(), &sc->sc_usp);
+	SETUP(a0w); SETUP(a1w);
+	SETUP(a0x); SETUP(a1x);
+	SETUP(astat);
+	SETUP(rets);
+	SETUP(pc);
+	SETUP(retx);
+	SETUP(fp);
+	SETUP(i0); SETUP(i1); SETUP(i2); SETUP(i3);
+	SETUP(m0); SETUP(m1); SETUP(m2); SETUP(m3);
+	SETUP(l0); SETUP(l1); SETUP(l2); SETUP(l3);
+	SETUP(b0); SETUP(b1); SETUP(b2); SETUP(b3);
+	SETUP(lc0); SETUP(lc1);
+	SETUP(lt0); SETUP(lt1);
+	SETUP(lb0); SETUP(lb1);
+	SETUP(seqstat);
+
+	return err;
+}
+
+static inline void push_cache(unsigned long vaddr, unsigned int len)
+{
+	flush_icache_range(vaddr, vaddr + len);
+}
+
+static inline void *get_sigframe(struct k_sigaction *ka, struct pt_regs *regs,
+				 size_t frame_size)
+{
+	unsigned long usp;
+
+	/* Default to using normal stack.  */
+	usp = rdusp();
+
+	/* This is the X/Open sanctioned signal stack switching.  */
+	if (ka->sa.sa_flags & SA_ONSTACK) {
+		if (!on_sig_stack(usp))
+			usp = current->sas_ss_sp + current->sas_ss_size;
+	}
+	return (void *)((usp - frame_size) & -8UL);
+}
+
+static int
+setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t * info,
+	       sigset_t * set, struct pt_regs *regs)
+{
+	struct rt_sigframe *frame;
+	int err = 0;
+
+	frame = get_sigframe(ka, regs, sizeof(*frame));
+
+	err |= __put_user((current_thread_info()->exec_domain
+			   && current_thread_info()->exec_domain->signal_invmap
+			   && sig < 32
+			   ? current_thread_info()->exec_domain->
+			   signal_invmap[sig] : sig), &frame->sig);
+
+	err |= __put_user(&frame->info, &frame->pinfo);
+	err |= __put_user(&frame->uc, &frame->puc);
+	err |= copy_siginfo_to_user(&frame->info, info);
+
+	/* Create the ucontext.  */
+	err |= __put_user(0, &frame->uc.uc_flags);
+	err |= __put_user(0, &frame->uc.uc_link);
+	err |=
+	    __put_user((void *)current->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
+	err |= __put_user(sas_ss_flags(rdusp()), &frame->uc.uc_stack.ss_flags);
+	err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
+	err |= rt_setup_sigcontext(&frame->uc.uc_mcontext, regs);
+	err |= copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
+
+	/* Set up to return from userspace.  */
+	err |= __put_user(0x28, &(frame->retcode[0]));
+	err |= __put_user(0xe1, &(frame->retcode[1]));
+	err |= __put_user(0xad, &(frame->retcode[2]));
+	err |= __put_user(0x00, &(frame->retcode[3]));
+	err |= __put_user(0xa0, &(frame->retcode[4]));
+	err |= __put_user(0x00, &(frame->retcode[5]));
+
+	if (err)
+		goto give_sigsegv;
+
+	push_cache((unsigned long)&frame->retcode, sizeof(frame->retcode));
+
+	/* Set up registers for signal handler */
+	wrusp((unsigned long)frame);
+	if (get_personality & FDPIC_FUNCPTRS) {
+		struct fdpic_func_descriptor __user *funcptr =
+			(struct fdpic_func_descriptor *) ka->sa.sa_handler;
+		__get_user(regs->pc, &funcptr->text);
+		__get_user(regs->p3, &funcptr->GOT);
+	} else
+		regs->pc = (unsigned long)ka->sa.sa_handler;
+	regs->rets = (unsigned long)(frame->retcode);
+
+	regs->r0 = frame->sig;
+	regs->r1 = (unsigned long)(&frame->info);
+	regs->r2 = (unsigned long)(&frame->uc);
+
+	return 0;
+
+      give_sigsegv:
+	if (sig == SIGSEGV)
+		ka->sa.sa_handler = SIG_DFL;
+	force_sig(SIGSEGV, current);
+	return -EFAULT;
+}
+
+static inline void
+handle_restart(struct pt_regs *regs, struct k_sigaction *ka, int has_handler)
+{
+	switch (regs->r0) {
+	case -ERESTARTNOHAND:
+		if (!has_handler)
+			goto do_restart;
+		regs->r0 = -EINTR;
+		break;
+
+	case -ERESTARTSYS:
+		if (has_handler && !(ka->sa.sa_flags & SA_RESTART)) {
+			regs->r0 = -EINTR;
+			break;
+		}
+		/* fallthrough */
+	case -ERESTARTNOINTR:
+	      do_restart:
+		regs->p0 = regs->orig_p0;
+		regs->r0 = regs->orig_r0;
+		regs->pc -= 2;
+		break;
+	}
+}
+
+/*
+ * OK, we're invoking a handler
+ */
+static int
+handle_signal(int sig, siginfo_t *info, struct k_sigaction *ka,
+	      sigset_t *oldset, struct pt_regs *regs)
+{
+	int ret;
+
+	/* are we from a system call? to see pt_regs->orig_p0 */
+	if (regs->orig_p0 >= 0)
+		/* If so, check system call restarting.. */
+		handle_restart(regs, ka, 1);
+
+	/* set up the stack frame */
+	ret = setup_rt_frame(sig, ka, info, oldset, regs);
+
+	if (ret == 0) {
+		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.
+ *
+ * Note that we go through the signals twice: once to check the signals
+ * that the kernel can handle, and then we build all the user-level signal
+ * handling stack-frames in one go after that.
+ */
+asmlinkage void do_signal(struct pt_regs *regs)
+{
+	siginfo_t info;
+	int signr;
+	struct k_sigaction ka;
+	sigset_t *oldset;
+
+	current->thread.esp0 = (unsigned long)regs;
+
+	if (try_to_freeze())
+		goto no_signal;
+
+	if (test_thread_flag(TIF_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 TIF_RESTORE_SIGMASK flag */
+			if (test_thread_flag(TIF_RESTORE_SIGMASK))
+				clear_thread_flag(TIF_RESTORE_SIGMASK);
+		}
+
+		return;
+	}
+
+no_signal:
+	/* Did we come from a system call? */
+	if (regs->orig_p0 >= 0)
+		/* Restart the system call - no handlers present */
+		handle_restart(regs, NULL, 0);
+
+	/* if there's no signal to deliver, we just 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);
+	}
+}