patch-2.4.22 linux-2.4.22/arch/mips64/kernel/signal_n32.c

• Lines: 210
• Date: 2003-08-25 04:44:40.000000000 -0700
• Orig file: linux-2.4.21/arch/mips64/kernel/signal_n32.c
• Orig date: 1969-12-31 16:00:00.000000000 -0800

diff -urN linux-2.4.21/arch/mips64/kernel/signal_n32.c linux-2.4.22/arch/mips64/kernel/signal_n32.c
@@ -0,0 +1,209 @@
+/*
+ * Copyright (C) 2003 Broadcom Corporation
+ *
+ * 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, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ */
+
+#include <linux/config.h>
+#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/ptrace.h>
+#include <linux/unistd.h>
+
+#include <asm/asm.h>
+#include <asm/bitops.h>
+#include <asm/pgalloc.h>
+#include <asm/stackframe.h>
+#include <asm/uaccess.h>
+#include <asm/ucontext.h>
+#include <asm/system.h>
+#include <asm/fpu.h>
+
+#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
+
+/* IRIX compatible stack_t  */
+typedef struct sigaltstack32 {
+	s32 ss_sp;
+	__kernel_size_t32 ss_size;
+	int ss_flags;
+} stack32_t;
+
+struct ucontextn32 {
+	u32                 uc_flags;
+	s32                 uc_link;
+	stack32_t           uc_stack;
+	struct sigcontext   uc_mcontext;
+	sigset_t            uc_sigmask;   /* mask last for extensibility */
+};
+
+struct rt_sigframe_n32 {
+	u32 rs_ass[4];			/* argument save space for o32 */
+	u32 rs_code[2];			/* signal trampoline */
+	struct siginfo rs_info;
+	struct ucontextn32 rs_uc;
+};
+
+extern asmlinkage int restore_sigcontext(struct pt_regs *regs, struct sigcontext *sc);
+extern int inline setup_sigcontext(struct pt_regs *regs, struct sigcontext *sc);
+
+asmlinkage void sysn32_rt_sigreturn(abi64_no_regargs, struct pt_regs regs)
+{
+	struct rt_sigframe_n32 *frame;
+	sigset_t set;
+	stack_t st;
+	s32 sp;
+
+	frame = (struct rt_sigframe_n32 *) regs.regs[29];
+	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->sigmask_lock);
+	current->blocked = set;
+	recalc_sigpending(current);
+	spin_unlock_irq(&current->sigmask_lock);
+
+	if (restore_sigcontext(&regs, &frame->rs_uc.uc_mcontext))
+		goto badframe;
+
+	/* The ucontext contains a stack32_t, so we must convert!  */
+	if (__get_user(sp, &frame->rs_uc.uc_stack.ss_sp))
+		goto badframe;
+	st.ss_size = (long) sp;
+	if (__get_user(st.ss_size, &frame->rs_uc.uc_stack.ss_size))
+		goto badframe;
+	if (__get_user(st.ss_flags, &frame->rs_uc.uc_stack.ss_flags))
+		goto badframe;
+
+	/* It is more difficult to avoid calling this function than to
+	   call it and ignore errors.  */
+	do_sigaltstack(&st, NULL, regs.regs[29]);
+
+	/*
+	 * Don't let your children do this ...
+	 */
+	__asm__ __volatile__(
+		"move\t$29, %0\n\t"
+		"j\tret_from_sys_call"
+		:/* no outputs */
+		:"r" (&regs));
+	/* Unreached */
+
+badframe:
+	force_sig(SIGSEGV, current);
+}
+
+/*
+ * Determine which stack to use..
+ */
+static inline void *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[29];
+
+	/*
+ 	 * FPU emulator may have it's own trampoline active just
+ 	 * above the user stack, 16-bytes before the next lowest
+ 	 * 16 byte boundary.  Try to avoid trashing it.
+ 	 */
+ 	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 *)((sp - frame_size) & ALMASK);
+}
+
+void setup_rt_frame_n32(struct k_sigaction * ka,
+	struct pt_regs *regs, int signr, sigset_t *set, siginfo_t *info)
+{
+	struct rt_sigframe_n32 *frame;
+	int err = 0;
+	s32 sp;
+
+	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(0x24020000 + __NR_N32_rt_sigreturn, frame->rs_code + 0);
+	err |= __put_user(0x0000000c                    , frame->rs_code + 1);
+	flush_cache_sigtramp((unsigned long) frame->rs_code);
+
+	/* Create siginfo.  */
+	err |= copy_siginfo_to_user(&frame->rs_info, info);
+
+	/* Create the ucontext.  */
+	err |= __put_user(0, &frame->rs_uc.uc_flags);
+	err |= __put_user(0, &frame->rs_uc.uc_link);
+        sp = (int) (long) current->sas_ss_sp;
+	err |= __put_user(sp,
+	                  &frame->rs_uc.uc_stack.ss_sp);
+	err |= __put_user(sas_ss_flags(regs->regs[29]),
+	                  &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;
+
+	/*
+	 * Arguments to signal handler:
+	 *
+	 *   a0 = signal number
+	 *   a1 = 0 (should be cause)
+	 *   a2 = pointer to ucontext
+	 *
+	 * $25 and c0_epc point to the signal handler, $29 points to
+	 * the struct rt_sigframe.
+	 */
+	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) frame;
+	regs->regs[31] = (unsigned long) frame->rs_code;
+	regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler;
+
+#if DEBUG_SIG
+	printk("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%p\n",
+	       current->comm, current->pid,
+	       frame, regs->cp0_epc, regs->regs[31]);
+#endif
+	return;
+
+give_sigsegv:
+	if (signr == SIGSEGV)
+		ka->sa.sa_handler = SIG_DFL;
+	force_sig(SIGSEGV, current);
+}