Message-Id: <1251268435.3204.2.camel@ad3ser01>
Date:	Wed, 26 Aug 2009 14:33:55 +0800
From:	Chen Liqin <liqin.chen@...plusct.com>
To:	linux-arch@...r.kernel.org, linux-kernel@...r.kernel.org
Cc:	Arnd Bergmann <arnd@...db.de>, torvalds@...ux-foundation.org
Subject: Subject: [PATCH 27/33] score: create kernel/ files ptrace.c
	signal.c

>>From 0ba2890dbe62d88e267316c6fec5738f7fbc2b18 Mon Sep 17 00:00:00 2001
From: Chen Liqin <liqin.chen@...plusct.com>
Date: Wed, 26 Aug 2009 10:05:09 +0800
Subject: [PATCH 27/33] score: create kernel/ files ptrace.c signal.c


Signed-off-by: Chen Liqin <liqin.chen@...plusct.com>
---
 arch/score/kernel/ptrace.c |  382 ++++++++++++++++++++++++++++++++++++++++++++
 arch/score/kernel/signal.c |  361 +++++++++++++++++++++++++++++++++++++++++
 2 files changed, 743 insertions(+), 0 deletions(-)
 create mode 100644 arch/score/kernel/ptrace.c
 create mode 100644 arch/score/kernel/signal.c

diff --git a/arch/score/kernel/ptrace.c b/arch/score/kernel/ptrace.c
new file mode 100644
index 0000000..174c642
--- /dev/null
+++ b/arch/score/kernel/ptrace.c
@@ -0,0 +1,382 @@
+/*
+ * arch/score/kernel/ptrace.c
+ *
+ * Score Processor version.
+ *
+ * Copyright (C) 2009 Sunplus Core Technology Co., Ltd.
+ *  Chen Liqin <liqin.chen@...plusct.com>
+ *  Lennox Wu <lennox.wu@...plusct.com>
+ *
+ * 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/elf.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/ptrace.h>
+#include <linux/regset.h>
+
+#include <asm/uaccess.h>
+
+/*
+ * retrieve the contents of SCORE userspace general registers
+ */
+static int genregs_get(struct task_struct *target,
+		       const struct user_regset *regset,
+		       unsigned int pos, unsigned int count,
+		       void *kbuf, void __user *ubuf)
+{
+	const struct pt_regs *regs = task_pt_regs(target);
+	int ret;
+
+	/* skip 9 * sizeof(unsigned long) not use for pt_regs */
+	ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
+					0, offsetof(struct pt_regs, regs));
+
+	/* r0 - r31, cel, ceh, sr0, sr1, sr2, epc, ema, psr, ecr, condition */
+	ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
+				  regs->regs,
+				  offsetof(struct pt_regs, regs),
+				  offsetof(struct pt_regs, cp0_condition));
+
+	if (!ret)
+		ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
+						sizeof(struct pt_regs), -1);
+
+	return ret;
+}
+
+/*
+ * update the contents of the SCORE userspace general registers
+ */
+static int genregs_set(struct task_struct *target,
+		       const struct user_regset *regset,
+		       unsigned int pos, unsigned int count,
+		       const void *kbuf, const void __user *ubuf)
+{
+	struct pt_regs *regs = task_pt_regs(target);
+	int ret;
+
+	/* skip 9 * sizeof(unsigned long) */
+	ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
+					0, offsetof(struct pt_regs, regs));
+
+	/* r0 - r31, cel, ceh, sr0, sr1, sr2, epc, ema, psr, ecr, condition */
+	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+				  regs->regs,
+				  offsetof(struct pt_regs, regs),
+				  offsetof(struct pt_regs, cp0_condition));
+
+	if (!ret)
+		ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
+						sizeof(struct pt_regs), -1);
+
+	return ret;
+}
+
+/*
+ * Define the register sets available on the score7 under Linux
+ */
+enum score7_regset {
+	REGSET_GENERAL,
+};
+
+static const struct user_regset score7_regsets[] = {
+	[REGSET_GENERAL] = {
+		.core_note_type	= NT_PRSTATUS,
+		.n		= ELF_NGREG,
+		.size		= sizeof(long),
+		.align		= sizeof(long),
+		.get		= genregs_get,
+		.set		= genregs_set,
+	},
+};
+
+static const struct user_regset_view user_score_native_view = {
+	.name		= "score7",
+	.e_machine	= EM_SCORE7,
+	.regsets	= score7_regsets,
+	.n		= ARRAY_SIZE(score7_regsets),
+};
+
+const struct user_regset_view *task_user_regset_view(struct task_struct *task)
+{
+	return &user_score_native_view;
+}
+
+static int is_16bitinsn(unsigned long insn)
+{
+	if ((insn & INSN32_MASK) == INSN32_MASK)
+		return 0;
+	else
+		return 1;
+}
+
+int
+read_tsk_long(struct task_struct *child,
+		unsigned long addr, unsigned long *res)
+{
+	int copied;
+
+	copied = access_process_vm(child, addr, res, sizeof(*res), 0);
+
+	return copied != sizeof(*res) ? -EIO : 0;
+}
+
+int
+read_tsk_short(struct task_struct *child,
+		unsigned long addr, unsigned short *res)
+{
+	int copied;
+
+	copied = access_process_vm(child, addr, res, sizeof(*res), 0);
+
+	return copied != sizeof(*res) ? -EIO : 0;
+}
+
+static int
+write_tsk_short(struct task_struct *child,
+		unsigned long addr, unsigned short val)
+{
+	int copied;
+
+	copied = access_process_vm(child, addr, &val, sizeof(val), 1);
+
+	return copied != sizeof(val) ? -EIO : 0;
+}
+
+static int
+write_tsk_long(struct task_struct *child,
+		unsigned long addr, unsigned long val)
+{
+	int copied;
+
+	copied = access_process_vm(child, addr, &val, sizeof(val), 1);
+
+	return copied != sizeof(val) ? -EIO : 0;
+}
+
+void user_enable_single_step(struct task_struct *child)
+{
+	/* far_epc is the target of branch */
+	unsigned int epc, far_epc = 0;
+	unsigned long epc_insn, far_epc_insn;
+	int ninsn_type;			/* next insn type 0=16b, 1=32b */
+	unsigned int tmp, tmp2;
+	struct pt_regs *regs = task_pt_regs(child);
+	child->thread.single_step = 1;
+	child->thread.ss_nextcnt = 1;
+	epc = regs->cp0_epc;
+
+	read_tsk_long(child, epc, &epc_insn);
+
+	if (is_16bitinsn(epc_insn)) {
+		if ((epc_insn & J16M) == J16) {
+			tmp = epc_insn & 0xFFE;
+			epc = (epc & 0xFFFFF000) | tmp;
+		} else if ((epc_insn & B16M) == B16) {
+			child->thread.ss_nextcnt = 2;
+			tmp = (epc_insn & 0xFF) << 1;
+			tmp = tmp << 23;
+			tmp = (unsigned int)((int) tmp >> 23);
+			far_epc = epc + tmp;
+			epc += 2;
+		} else if ((epc_insn & BR16M) == BR16) {
+			child->thread.ss_nextcnt = 2;
+			tmp = (epc_insn >> 4) & 0xF;
+			far_epc = regs->regs[tmp];
+			epc += 2;
+		} else
+			epc += 2;
+	} else {
+		if ((epc_insn & J32M) == J32) {
+			tmp = epc_insn & 0x03FFFFFE;
+			tmp2 = tmp & 0x7FFF;
+			tmp = (((tmp >> 16) & 0x3FF) << 15) | tmp2;
+			epc = (epc & 0xFFC00000) | tmp;
+		} else if ((epc_insn & B32M) == B32) {
+			child->thread.ss_nextcnt = 2;
+			tmp = epc_insn & 0x03FFFFFE;	/* discard LK bit */
+			tmp2 = tmp & 0x3FF;
+			tmp = (((tmp >> 16) & 0x3FF) << 10) | tmp2; /* 20bit */
+			tmp = tmp << 12;
+			tmp = (unsigned int)((int) tmp >> 12);
+			far_epc = epc + tmp;
+			epc += 4;
+		} else if ((epc_insn & BR32M) == BR32) {
+			child->thread.ss_nextcnt = 2;
+			tmp = (epc_insn >> 16) & 0x1F;
+			far_epc = regs->regs[tmp];
+			epc += 4;
+		} else
+			epc += 4;
+	}
+
+	if (child->thread.ss_nextcnt == 1) {
+		read_tsk_long(child, epc, &epc_insn);
+
+		if (is_16bitinsn(epc_insn)) {
+			write_tsk_short(child, epc, SINGLESTEP16_INSN);
+			ninsn_type = 0;
+		} else {
+			write_tsk_long(child, epc, SINGLESTEP32_INSN);
+			ninsn_type = 1;
+		}
+
+		if (ninsn_type == 0) {  /* 16bits */
+			child->thread.insn1_type = 0;
+			child->thread.addr1 = epc;
+			 /* the insn may have 32bit data */
+			child->thread.insn1 = (short)epc_insn;
+		} else {
+			child->thread.insn1_type = 1;
+			child->thread.addr1 = epc;
+			child->thread.insn1 = epc_insn;
+		}
+	} else {
+		/* branch! have two target child->thread.ss_nextcnt=2 */
+		read_tsk_long(child, epc, &epc_insn);
+		read_tsk_long(child, far_epc, &far_epc_insn);
+		if (is_16bitinsn(epc_insn)) {
+			write_tsk_short(child, epc, SINGLESTEP16_INSN);
+			ninsn_type = 0;
+		} else {
+			write_tsk_long(child, epc, SINGLESTEP32_INSN);
+			ninsn_type = 1;
+		}
+
+		if (ninsn_type == 0) {  /* 16bits */
+			child->thread.insn1_type = 0;
+			child->thread.addr1 = epc;
+			 /* the insn may have 32bit data */
+			child->thread.insn1 = (short)epc_insn;
+		} else {
+			child->thread.insn1_type = 1;
+			child->thread.addr1 = epc;
+			child->thread.insn1 = epc_insn;
+		}
+
+		if (is_16bitinsn(far_epc_insn)) {
+			write_tsk_short(child, far_epc, SINGLESTEP16_INSN);
+			ninsn_type = 0;
+		} else {
+			write_tsk_long(child, far_epc, SINGLESTEP32_INSN);
+			ninsn_type = 1;
+		}
+
+		if (ninsn_type == 0) {  /* 16bits */
+			child->thread.insn2_type = 0;
+			child->thread.addr2 = far_epc;
+			 /* the insn may have 32bit data */
+			child->thread.insn2 = (short)far_epc_insn;
+		} else {
+			child->thread.insn2_type = 1;
+			child->thread.addr2 = far_epc;
+			child->thread.insn2 = far_epc_insn;
+		}
+	}
+}
+
+void user_disable_single_step(struct task_struct *child)
+{
+	if (child->thread.insn1_type == 0)
+		write_tsk_short(child, child->thread.addr1,
+				child->thread.insn1);
+
+	if (child->thread.insn1_type == 1)
+		write_tsk_long(child, child->thread.addr1,
+				child->thread.insn1);
+
+	if (child->thread.ss_nextcnt == 2) {	/* branch */
+		if (child->thread.insn1_type == 0)
+			write_tsk_short(child, child->thread.addr1,
+					child->thread.insn1);
+		if (child->thread.insn1_type == 1)
+			write_tsk_long(child, child->thread.addr1,
+					child->thread.insn1);
+		if (child->thread.insn2_type == 0)
+			write_tsk_short(child, child->thread.addr2,
+					child->thread.insn2);
+		if (child->thread.insn2_type == 1)
+			write_tsk_long(child, child->thread.addr2,
+					child->thread.insn2);
+	}
+
+	child->thread.single_step = 0;
+	child->thread.ss_nextcnt = 0;
+}
+
+void ptrace_disable(struct task_struct *child)
+{
+	user_disable_single_step(child);
+}
+
+long
+arch_ptrace(struct task_struct *child, long request, long addr, long data)
+{
+	int ret;
+	unsigned long __user *datap = (void __user *)data;
+
+	switch (request) {
+	case PTRACE_GETREGS:
+		ret = copy_regset_to_user(child, &user_score_native_view,
+						REGSET_GENERAL,
+						0, sizeof(struct pt_regs),
+						(void __user *)datap);
+		break;
+
+	case PTRACE_SETREGS:
+		ret = copy_regset_from_user(child, &user_score_native_view,
+						REGSET_GENERAL,
+						0, sizeof(struct pt_regs),
+						(const void __user *)datap);
+		break;
+
+	default:
+		ret = ptrace_request(child, request, addr, data);
+		break;
+	}
+
+	return ret;
+}
+
+/*
+ * Notification of system call entry/exit
+ * - triggered by current->work.syscall_trace
+ */
+asmlinkage void do_syscall_trace(struct pt_regs *regs, int entryexit)
+{
+	if (!(current->ptrace & PT_PTRACED))
+		return;
+
+	if (!test_thread_flag(TIF_SYSCALL_TRACE))
+		return;
+
+	/* The 0x80 provides a way for the tracing parent to distinguish
+	   between a syscall stop and SIGTRAP delivery. */
+	ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD) ?
+			0x80 : 0));
+
+	/*
+	 * this isn't the same as continuing with a signal, but it will do
+	 * for normal use.  strace only continues with a signal if the
+	 * stopping signal is not SIGTRAP.  -brl
+	 */
+	if (current->exit_code) {
+		send_sig(current->exit_code, current, 1);
+		current->exit_code = 0;
+	}
+}
diff --git a/arch/score/kernel/signal.c b/arch/score/kernel/signal.c
new file mode 100644
index 0000000..950f87c
--- /dev/null
+++ b/arch/score/kernel/signal.c
@@ -0,0 +1,361 @@
+/*
+ * arch/score/kernel/signal.c
+ *
+ * Score Processor version.
+ *
+ * Copyright (C) 2009 Sunplus Core Technology Co., Ltd.
+ *  Chen Liqin <liqin.chen@...plusct.com>
+ *  Lennox Wu <lennox.wu@...plusct.com>
+ *
+ * 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/errno.h>
+#include <linux/signal.h>
+#include <linux/unistd.h>
+#include <linux/uaccess.h>
+
+#include <asm/syscalls.h>
+#include <asm/ucontext.h>
+
+#include <asm/cacheflush.h>
+
+#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
+
+struct rt_sigframe {
+	u32 rs_ass[4];		/* argument save space */
+	u32 rs_code[2];		/* signal trampoline */
+	struct siginfo rs_info;
+	struct ucontext rs_uc;
+};
+
+static int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
+{
+	int err = 0;
+	unsigned long reg;
+
+	reg = regs->cp0_epc; err |= __put_user(reg, &sc->sc_pc);
+	err |= __put_user(regs->cp0_psr, &sc->sc_psr);
+	err |= __put_user(regs->cp0_condition, &sc->sc_condition);
+
+
+#define save_gp_reg(i) {				\
+	reg = regs->regs[i];				\
+	err |= __put_user(reg, &sc->sc_regs[i]);	\
+} while (0)
+	save_gp_reg(0); save_gp_reg(1); save_gp_reg(2);
+	save_gp_reg(3); save_gp_reg(4); save_gp_reg(5);
+	save_gp_reg(6);	save_gp_reg(7); save_gp_reg(8);
+	save_gp_reg(9); save_gp_reg(10); save_gp_reg(11);
+	save_gp_reg(12); save_gp_reg(13); save_gp_reg(14);
+	save_gp_reg(15); save_gp_reg(16); save_gp_reg(17);
+	save_gp_reg(18); save_gp_reg(19); save_gp_reg(20);
+	save_gp_reg(21); save_gp_reg(22); save_gp_reg(23);
+	save_gp_reg(24); save_gp_reg(25); save_gp_reg(26);
+	save_gp_reg(27); save_gp_reg(28); save_gp_reg(29);
+#undef save_gp_reg
+
+	reg = regs->ceh; err |= __put_user(reg, &sc->sc_mdceh);
+	reg = regs->cel; err |= __put_user(reg, &sc->sc_mdcel);
+	err |= __put_user(regs->cp0_ecr, &sc->sc_ecr);
+	err |= __put_user(regs->cp0_ema, &sc->sc_ema);
+
+	return err;
+}
+
+static int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
+{
+	int err = 0;
+	u32 reg;
+
+	err |= __get_user(regs->cp0_epc, &sc->sc_pc);
+	err |= __get_user(regs->cp0_condition, &sc->sc_condition);
+
+	err |= __get_user(reg, &sc->sc_mdceh);
+	regs->ceh = (int) reg;
+	err |= __get_user(reg, &sc->sc_mdcel);
+	regs->cel = (int) reg;
+
+	err |= __get_user(reg, &sc->sc_psr);
+	regs->cp0_psr = (int) reg;
+	err |= __get_user(reg, &sc->sc_ecr);
+	regs->cp0_ecr = (int) reg;
+	err |= __get_user(reg, &sc->sc_ema);
+	regs->cp0_ema = (int) reg;
+
+#define restore_gp_reg(i) do {				\
+	err |= __get_user(reg, &sc->sc_regs[i]);	\
+	regs->regs[i] = reg;				\
+} while (0)
+	restore_gp_reg(0); restore_gp_reg(1); restore_gp_reg(2);
+	restore_gp_reg(3); restore_gp_reg(4); restore_gp_reg(5);
+	restore_gp_reg(6); restore_gp_reg(7); restore_gp_reg(8);
+	restore_gp_reg(9); restore_gp_reg(10); restore_gp_reg(11);
+	restore_gp_reg(12); restore_gp_reg(13); restore_gp_reg(14);
+	restore_gp_reg(15); restore_gp_reg(16); restore_gp_reg(17);
+	restore_gp_reg(18); restore_gp_reg(19);	restore_gp_reg(20);
+	restore_gp_reg(21); restore_gp_reg(22); restore_gp_reg(23);
+	restore_gp_reg(24); restore_gp_reg(25); restore_gp_reg(26);
+	restore_gp_reg(27); restore_gp_reg(28); restore_gp_reg(29);
+#undef restore_gp_reg
+
+	return err;
+}
+
+/*
+ * Determine which stack to use..
+ */
+static 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->regs[0];
+	sp -= 32;
+
+	/* This is the X/Open sanctioned signal stack switching.  */
+	if ((ka->sa.sa_flags & SA_ONSTACK) && (!on_sig_stack(sp)))
+		sp = current->sas_ss_sp + current->sas_ss_size;
+
+	return (void __user*)((sp - frame_size) & ~7);
+}
+
+asmlinkage long
+score_sigaltstack(struct pt_regs *regs)
+{
+	const stack_t __user *uss = (const stack_t __user *) regs->regs[4];
+	stack_t __user *uoss = (stack_t __user *) regs->regs[5];
+	unsigned long usp = regs->regs[0];
+
+	return do_sigaltstack(uss, uoss, usp);
+}
+
+asmlinkage long
+score_rt_sigreturn(struct pt_regs *regs)
+{
+	struct rt_sigframe __user *frame;
+	sigset_t set;
+	stack_t st;
+	int sig;
+
+	frame = (struct rt_sigframe __user *) regs->regs[0];
+	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
+		goto badframe;
+	if (__copy_from_user(&set, &frame->rs_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);
+
+	sig = restore_sigcontext(regs, &frame->rs_uc.uc_mcontext);
+	if (sig < 0)
+		goto badframe;
+	else if (sig)
+		force_sig(sig, current);
+
+	if (__copy_from_user(&st, &frame->rs_uc.uc_stack, sizeof(st)))
+		goto badframe;
+
+	/* It is more difficult to avoid calling this function than to
+	   call it and ignore errors.  */
+	do_sigaltstack((stack_t __user *)&st, NULL, regs->regs[0]);
+
+	__asm__ __volatile__(
+		"mv\tr0, %0\n\t"
+		"la\tr8, syscall_exit\n\t"
+		"br\tr8\n\t"
+		: : "r" (regs) : "r8");
+
+badframe:
+	force_sig(SIGSEGV, current);
+
+	return 0;
+}
+
+static int setup_rt_frame(struct k_sigaction *ka, struct pt_regs *regs,
+		int signr, sigset_t *set, siginfo_t *info)
+{
+	struct rt_sigframe __user *frame;
+	int err = 0;
+
+	frame = get_sigframe(ka, regs, sizeof(*frame));
+	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
+		goto give_sigsegv;
+
+	/*
+	 * Set up the return code ...
+	 *
+	 *         li      v0, __NR_rt_sigreturn
+	 *         syscall
+	 */
+	err |= __put_user(0x87788000 + __NR_rt_sigreturn*2,
+			frame->rs_code + 0);
+	err |= __put_user(0x80008002, frame->rs_code + 1);
+	flush_cache_sigtramp((unsigned long) frame->rs_code);
+
+	err |= copy_siginfo_to_user(&frame->rs_info, info);
+	err |= __put_user(0, &frame->rs_uc.uc_flags);
+	err |= __put_user(NULL, &frame->rs_uc.uc_link);
+	err |= __put_user((void __user *)current->sas_ss_sp,
+				&frame->rs_uc.uc_stack.ss_sp);
+	err |= __put_user(sas_ss_flags(regs->regs[0]),
+				&frame->rs_uc.uc_stack.ss_flags);
+	err |= __put_user(current->sas_ss_size,
+				&frame->rs_uc.uc_stack.ss_size);
+	err |= setup_sigcontext(regs, &frame->rs_uc.uc_mcontext);
+	err |= __copy_to_user(&frame->rs_uc.uc_sigmask, set, sizeof(*set));
+
+	if (err)
+		goto give_sigsegv;
+
+	regs->regs[0] = (unsigned long) frame;
+	regs->regs[3] = (unsigned long) frame->rs_code;
+	regs->regs[4] = signr;
+	regs->regs[5] = (unsigned long) &frame->rs_info;
+	regs->regs[6] = (unsigned long) &frame->rs_uc;
+	regs->regs[29] = (unsigned long) ka->sa.sa_handler;
+	regs->cp0_epc = (unsigned long) ka->sa.sa_handler;
+
+	return 0;
+
+give_sigsegv:
+	if (signr == SIGSEGV)
+		ka->sa.sa_handler = SIG_DFL;
+	force_sig(SIGSEGV, current);
+	return -EFAULT;
+}
+
+static int handle_signal(unsigned long sig, siginfo_t *info,
+	struct k_sigaction *ka, sigset_t *oldset, struct pt_regs *regs)
+{
+	int ret;
+
+	if (regs->is_syscall) {
+		switch (regs->regs[4]) {
+		case ERESTART_RESTARTBLOCK:
+		case ERESTARTNOHAND:
+			regs->regs[4] = EINTR;
+			break;
+		case ERESTARTSYS:
+			if (!(ka->sa.sa_flags & SA_RESTART)) {
+				regs->regs[4] = EINTR;
+				break;
+			}
+		case ERESTARTNOINTR:
+			regs->regs[4] = regs->orig_r4;
+			regs->regs[7] = regs->orig_r7;
+			regs->cp0_epc -= 8;
+		}
+
+		regs->is_syscall = 0;
+	}
+
+	/*
+	 * Set up the stack frame
+	 */
+	ret = setup_rt_frame(ka, regs, sig, oldset, info);
+
+	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;
+}
+
+static void do_signal(struct pt_regs *regs)
+{
+	struct k_sigaction ka;
+	sigset_t *oldset;
+	siginfo_t info;
+	int signr;
+
+	/*
+	 * We want the common case to go fast, which is why we may in certain
+	 * cases get here from kernel mode. Just return without doing anything
+	 * if so.
+	 */
+	if (!user_mode(regs))
+		return;
+
+	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) {
+		/* 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;
+	}
+
+	if (regs->is_syscall) {
+		if (regs->regs[4] == ERESTARTNOHAND ||
+		    regs->regs[4] == ERESTARTSYS ||
+		    regs->regs[4] == ERESTARTNOINTR) {
+			regs->regs[4] = regs->orig_r4;
+			regs->regs[7] = regs->orig_r7;
+			regs->cp0_epc -= 8;
+		}
+
+		if (regs->regs[4] == ERESTART_RESTARTBLOCK) {
+			regs->regs[27] = __NR_restart_syscall;
+			regs->regs[4] = regs->orig_r4;
+			regs->regs[7] = regs->orig_r7;
+			regs->cp0_epc -= 8;
+		}
+
+		regs->is_syscall = 0;	/* Don't deal with this again.  */
+	}
+
+	/*
+	 * 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);
+	}
+}
+
+/*
+ * notification of userspace execution resumption
+ * - triggered by the TIF_WORK_MASK flags
+ */
+asmlinkage void do_notify_resume(struct pt_regs *regs, void *unused,
+				__u32 thread_info_flags)
+{
+	/* deal with pending signal delivery */
+	if (thread_info_flags & (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK))
+		do_signal(regs);
+}
-- 
1.6.2



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