Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 829 insertions, 0 deletions

diff --git a/arch/m32r/kernel/ptrace.c b/arch/m32r/kernel/ptrace.c
new file mode 100644
index 00000000000..8b40f362dd6
--- /dev/null
+++ b/arch/m32r/kernel/ptrace.c
@@ -0,0 +1,829 @@
+/*
+ * linux/arch/m32r/kernel/ptrace.c
+ *
+ * Copyright (C) 2002  Hirokazu Takata, Takeo Takahashi
+ * Copyright (C) 2004  Hirokazu Takata, Kei Sakamoto
+ *
+ * Original x86 implementation:
+ *	By Ross Biro 1/23/92
+ *	edited by Linus Torvalds
+ *
+ * Some code taken from sh version:
+ *   Copyright (C) 1999, 2000  Kaz Kojima & Niibe Yutaka
+ * Some code taken from arm version:
+ *   Copyright (C) 2000 Russell King
+ */
+
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/smp_lock.h>
+#include <linux/errno.h>
+#include <linux/ptrace.h>
+#include <linux/user.h>
+#include <linux/string.h>
+
+#include <asm/cacheflush.h>
+#include <asm/io.h>
+#include <asm/uaccess.h>
+#include <asm/pgtable.h>
+#include <asm/system.h>
+#include <asm/processor.h>
+#include <asm/mmu_context.h>
+
+/*
+ * Get the address of the live pt_regs for the specified task.
+ * These are saved onto the top kernel stack when the process
+ * is not running.
+ *
+ * Note: if a user thread is execve'd from kernel space, the
+ * kernel stack will not be empty on entry to the kernel, so
+ * ptracing these tasks will fail.
+ */
+static inline struct pt_regs *
+get_user_regs(struct task_struct *task)
+{
+        return (struct pt_regs *)
+                ((unsigned long)task->thread_info + THREAD_SIZE
+                 - sizeof(struct pt_regs));
+}
+
+/*
+ * This routine will get a word off of the process kernel stack.
+ */
+static inline unsigned long int
+get_stack_long(struct task_struct *task, int offset)
+{
+	unsigned long *stack;
+
+	stack = (unsigned long *)get_user_regs(task);
+
+	return stack[offset];
+}
+
+/*
+ * This routine will put a word on the process kernel stack.
+ */
+static inline int
+put_stack_long(struct task_struct *task, int offset, unsigned long data)
+{
+	unsigned long *stack;
+
+	stack = (unsigned long *)get_user_regs(task);
+	stack[offset] = data;
+
+	return 0;
+}
+
+static int reg_offset[] = {
+	PT_R0, PT_R1, PT_R2, PT_R3, PT_R4, PT_R5, PT_R6, PT_R7,
+	PT_R8, PT_R9, PT_R10, PT_R11, PT_R12, PT_FP, PT_LR, PT_SPU,
+};
+
+/*
+ * Read the word at offset "off" into the "struct user".  We
+ * actually access the pt_regs stored on the kernel stack.
+ */
+static int ptrace_read_user(struct task_struct *tsk, unsigned long off,
+			    unsigned long __user *data)
+{
+	unsigned long tmp;
+#ifndef NO_FPU
+	struct user * dummy = NULL;
+#endif
+
+	if ((off & 3) || (off < 0) || (off > sizeof(struct user) - 3))
+		return -EIO;
+
+	off >>= 2;
+	switch (off) {
+	case PT_EVB:
+		__asm__ __volatile__ (
+			"mvfc	%0, cr5 \n\t"
+	 		: "=r" (tmp)
+		);
+		break;
+	case PT_CBR: {
+			unsigned long psw;
+			psw = get_stack_long(tsk, PT_PSW);
+			tmp = ((psw >> 8) & 1);
+		}
+		break;
+	case PT_PSW: {
+			unsigned long psw, bbpsw;
+			psw = get_stack_long(tsk, PT_PSW);
+			bbpsw = get_stack_long(tsk, PT_BBPSW);
+			tmp = ((psw >> 8) & 0xff) | ((bbpsw & 0xff) << 8);
+		}
+		break;
+	case PT_PC:
+		tmp = get_stack_long(tsk, PT_BPC);
+		break;
+	case PT_BPC:
+		off = PT_BBPC;
+		/* fall through */
+	default:
+		if (off < (sizeof(struct pt_regs) >> 2))
+			tmp = get_stack_long(tsk, off);
+#ifndef NO_FPU
+		else if (off >= (long)(&dummy->fpu >> 2) &&
+			 off < (long)(&dummy->u_fpvalid >> 2)) {
+			if (!tsk_used_math(tsk)) {
+				if (off == (long)(&dummy->fpu.fpscr >> 2))
+					tmp = FPSCR_INIT;
+				else
+					tmp = 0;
+			} else
+				tmp = ((long *)(&tsk->thread.fpu >> 2))
+					[off - (long)&dummy->fpu];
+		} else if (off == (long)(&dummy->u_fpvalid >> 2))
+			tmp = !!tsk_used_math(tsk);
+#endif /* not NO_FPU */
+		else
+			tmp = 0;
+	}
+
+	return put_user(tmp, data);
+}
+
+static int ptrace_write_user(struct task_struct *tsk, unsigned long off,
+			     unsigned long data)
+{
+	int ret = -EIO;
+#ifndef NO_FPU
+	struct user * dummy = NULL;
+#endif
+
+	if ((off & 3) || off < 0 ||
+	    off > sizeof(struct user) - 3)
+		return -EIO;
+
+	off >>= 2;
+	switch (off) {
+	case PT_EVB:
+	case PT_BPC:
+	case PT_SPI:
+		/* We don't allow to modify evb. */
+		ret = 0;
+		break;
+	case PT_PSW:
+	case PT_CBR: {
+			/* We allow to modify only cbr in psw */
+			unsigned long psw;
+			psw = get_stack_long(tsk, PT_PSW);
+			psw = (psw & ~0x100) | ((data & 1) << 8);
+			ret = put_stack_long(tsk, PT_PSW, psw);
+		}
+		break;
+	case PT_PC:
+		off = PT_BPC;
+		data &= ~1;
+		/* fall through */
+	default:
+		if (off < (sizeof(struct pt_regs) >> 2))
+			ret = put_stack_long(tsk, off, data);
+#ifndef NO_FPU
+		else if (off >= (long)(&dummy->fpu >> 2) &&
+			 off < (long)(&dummy->u_fpvalid >> 2)) {
+			set_stopped_child_used_math(tsk);
+			((long *)&tsk->thread.fpu)
+				[off - (long)&dummy->fpu] = data;
+			ret = 0;
+		} else if (off == (long)(&dummy->u_fpvalid >> 2)) {
+			conditional_stopped_child_used_math(data, tsk);
+			ret = 0;
+		}
+#endif /* not NO_FPU */
+		break;
+	}
+
+	return ret;
+}
+
+/*
+ * Get all user integer registers.
+ */
+static int ptrace_getregs(struct task_struct *tsk, void __user *uregs)
+{
+	struct pt_regs *regs = get_user_regs(tsk);
+
+	return copy_to_user(uregs, regs, sizeof(struct pt_regs)) ? -EFAULT : 0;
+}
+
+/*
+ * Set all user integer registers.
+ */
+static int ptrace_setregs(struct task_struct *tsk, void __user *uregs)
+{
+	struct pt_regs newregs;
+	int ret;
+
+	ret = -EFAULT;
+	if (copy_from_user(&newregs, uregs, sizeof(struct pt_regs)) == 0) {
+		struct pt_regs *regs = get_user_regs(tsk);
+		*regs = newregs;
+		ret = 0;
+	}
+
+	return ret;
+}
+
+
+static inline int
+check_condition_bit(struct task_struct *child)
+{
+	return (int)((get_stack_long(child, PT_PSW) >> 8) & 1);
+}
+
+static int
+check_condition_src(unsigned long op, unsigned long regno1,
+		    unsigned long regno2, struct task_struct *child)
+{
+	unsigned long reg1, reg2;
+
+	reg2 = get_stack_long(child, reg_offset[regno2]);
+
+	switch (op) {
+	case 0x0: /* BEQ */
+		reg1 = get_stack_long(child, reg_offset[regno1]);
+		return reg1 == reg2;
+	case 0x1: /* BNE */
+		reg1 = get_stack_long(child, reg_offset[regno1]);
+		return reg1 != reg2;
+	case 0x8: /* BEQZ */
+		return reg2 == 0;
+	case 0x9: /* BNEZ */
+		return reg2 != 0;
+	case 0xa: /* BLTZ */
+		return (int)reg2 < 0;
+	case 0xb: /* BGEZ */
+		return (int)reg2 >= 0;
+	case 0xc: /* BLEZ */
+		return (int)reg2 <= 0;
+	case 0xd: /* BGTZ */
+		return (int)reg2 > 0;
+	default:
+		/* never reached */
+		return 0;
+	}
+}
+
+static void
+compute_next_pc_for_16bit_insn(unsigned long insn, unsigned long pc,
+			       unsigned long *next_pc,
+			       struct task_struct *child)
+{
+	unsigned long op, op2, op3;
+	unsigned long disp;
+	unsigned long regno;
+	int parallel = 0;
+
+	if (insn & 0x00008000)
+		parallel = 1;
+	if (pc & 3)
+		insn &= 0x7fff;	/* right slot */
+	else
+		insn >>= 16;	/* left slot */
+
+	op = (insn >> 12) & 0xf;
+	op2 = (insn >> 8) & 0xf;
+	op3 = (insn >> 4) & 0xf;
+
+	if (op == 0x7) {
+		switch (op2) {
+		case 0xd: /* BNC */
+		case 0x9: /* BNCL */
+			if (!check_condition_bit(child)) {
+				disp = (long)(insn << 24) >> 22;
+				*next_pc = (pc & ~0x3) + disp;
+				return;
+			}
+			break;
+		case 0x8: /* BCL */
+		case 0xc: /* BC */
+			if (check_condition_bit(child)) {
+				disp = (long)(insn << 24) >> 22;
+				*next_pc = (pc & ~0x3) + disp;
+				return;
+			}
+			break;
+		case 0xe: /* BL */
+		case 0xf: /* BRA */
+			disp = (long)(insn << 24) >> 22;
+			*next_pc = (pc & ~0x3) + disp;
+			return;
+			break;
+		}
+	} else if (op == 0x1) {
+		switch (op2) {
+		case 0x0:
+			if (op3 == 0xf) { /* TRAP */
+#if 1
+				/* pass through */
+#else
+ 				/* kernel space is not allowed as next_pc */
+				unsigned long evb;
+				unsigned long trapno;
+				trapno = insn & 0xf;
+				__asm__ __volatile__ (
+					"mvfc %0, cr5\n"
+		 			:"=r"(evb)
+		 			:
+				);
+				*next_pc = evb + (trapno << 2);
+				return;
+#endif
+			} else if (op3 == 0xd) { /* RTE */
+				*next_pc = get_stack_long(child, PT_BPC);
+				return;
+			}
+			break;
+		case 0xc: /* JC */
+			if (op3 == 0xc && check_condition_bit(child)) {
+				regno = insn & 0xf;
+				*next_pc = get_stack_long(child,
+							  reg_offset[regno]);
+				return;
+			}
+			break;
+		case 0xd: /* JNC */
+			if (op3 == 0xc && !check_condition_bit(child)) {
+				regno = insn & 0xf;
+				*next_pc = get_stack_long(child,
+							  reg_offset[regno]);
+				return;
+			}
+			break;
+		case 0xe: /* JL */
+		case 0xf: /* JMP */
+			if (op3 == 0xc) { /* JMP */
+				regno = insn & 0xf;
+				*next_pc = get_stack_long(child,
+							  reg_offset[regno]);
+				return;
+			}
+			break;
+		}
+	}
+	if (parallel)
+		*next_pc = pc + 4;
+	else
+		*next_pc = pc + 2;
+}
+
+static void
+compute_next_pc_for_32bit_insn(unsigned long insn, unsigned long pc,
+			       unsigned long *next_pc,
+			       struct task_struct *child)
+{
+	unsigned long op;
+	unsigned long op2;
+	unsigned long disp;
+	unsigned long regno1, regno2;
+
+	op = (insn >> 28) & 0xf;
+	if (op == 0xf) { 	/* branch 24-bit relative */
+		op2 = (insn >> 24) & 0xf;
+		switch (op2) {
+		case 0xd:	/* BNC */
+		case 0x9:	/* BNCL */
+			if (!check_condition_bit(child)) {
+				disp = (long)(insn << 8) >> 6;
+				*next_pc = (pc & ~0x3) + disp;
+				return;
+			}
+			break;
+		case 0x8:	/* BCL */
+		case 0xc:	/* BC */
+			if (check_condition_bit(child)) {
+				disp = (long)(insn << 8) >> 6;
+				*next_pc = (pc & ~0x3) + disp;
+				return;
+			}
+			break;
+		case 0xe:	/* BL */
+		case 0xf:	/* BRA */
+			disp = (long)(insn << 8) >> 6;
+			*next_pc = (pc & ~0x3) + disp;
+			return;
+		}
+	} else if (op == 0xb) { /* branch 16-bit relative */
+		op2 = (insn >> 20) & 0xf;
+		switch (op2) {
+		case 0x0: /* BEQ */
+		case 0x1: /* BNE */
+		case 0x8: /* BEQZ */
+		case 0x9: /* BNEZ */
+		case 0xa: /* BLTZ */
+		case 0xb: /* BGEZ */
+		case 0xc: /* BLEZ */
+		case 0xd: /* BGTZ */
+			regno1 = ((insn >> 24) & 0xf);
+			regno2 = ((insn >> 16) & 0xf);
+			if (check_condition_src(op2, regno1, regno2, child)) {
+				disp = (long)(insn << 16) >> 14;
+				*next_pc = (pc & ~0x3) + disp;
+				return;
+			}
+			break;
+		}
+	}
+	*next_pc = pc + 4;
+}
+
+static inline void
+compute_next_pc(unsigned long insn, unsigned long pc,
+		unsigned long *next_pc, struct task_struct *child)
+{
+	if (insn & 0x80000000)
+		compute_next_pc_for_32bit_insn(insn, pc, next_pc, child);
+	else
+		compute_next_pc_for_16bit_insn(insn, pc, next_pc, child);
+}
+
+static int
+register_debug_trap(struct task_struct *child, unsigned long next_pc,
+	unsigned long next_insn, unsigned long *code)
+{
+	struct debug_trap *p = &child->thread.debug_trap;
+	unsigned long addr = next_pc & ~3;
+
+	if (p->nr_trap == MAX_TRAPS) {
+		printk("kernel BUG at %s %d: p->nr_trap = %d\n",
+					__FILE__, __LINE__, p->nr_trap);
+		return -1;
+	}
+	p->addr[p->nr_trap] = addr;
+	p->insn[p->nr_trap] = next_insn;
+	p->nr_trap++;
+	if (next_pc & 3) {
+		*code = (next_insn & 0xffff0000) | 0x10f1;
+		/* xxx --> TRAP1 */
+	} else {
+		if ((next_insn & 0x80000000) || (next_insn & 0x8000)) {
+			*code = 0x10f17000;
+			/* TRAP1 --> NOP */
+		} else {
+			*code = (next_insn & 0xffff) | 0x10f10000;
+			/* TRAP1 --> xxx */
+		}
+	}
+	return 0;
+}
+
+static int
+unregister_debug_trap(struct task_struct *child, unsigned long addr,
+		      unsigned long *code)
+{
+	struct debug_trap *p = &child->thread.debug_trap;
+        int i;
+
+	/* Search debug trap entry. */
+	for (i = 0; i < p->nr_trap; i++) {
+		if (p->addr[i] == addr)
+			break;
+	}
+	if (i >= p->nr_trap) {
+		/* The trap may be requested from debugger.
+		 * ptrace should do nothing in this case.
+		 */
+		return 0;
+	}
+
+	/* Recover orignal instruction code. */
+	*code = p->insn[i];
+
+	/* Shift debug trap entries. */
+	while (i < p->nr_trap - 1) {
+		p->insn[i] = p->insn[i + 1];
+		p->addr[i] = p->addr[i + 1];
+		i++;
+	}
+	p->nr_trap--;
+	return 1;
+}
+
+static void
+unregister_all_debug_traps(struct task_struct *child)
+{
+	struct debug_trap *p = &child->thread.debug_trap;
+	int i;
+
+	for (i = 0; i < p->nr_trap; i++)
+		access_process_vm(child, p->addr[i], &p->insn[i], sizeof(p->insn[i]), 1);
+	p->nr_trap = 0;
+}
+
+static inline void
+invalidate_cache(void)
+{
+#if defined(CONFIG_CHIP_M32700) || defined(CONFIG_CHIP_OPSP)
+
+	_flush_cache_copyback_all();
+
+#else	/* ! CONFIG_CHIP_M32700 */
+
+	/* Invalidate cache */
+	__asm__ __volatile__ (
+                "ldi    r0, #-1					\n\t"
+                "ldi    r1, #0					\n\t"
+                "stb    r1, @r0		; cache off		\n\t"
+                ";						\n\t"
+                "ldi    r0, #-2					\n\t"
+                "ldi    r1, #1					\n\t"
+                "stb    r1, @r0		; cache invalidate	\n\t"
+                ".fillinsn					\n"
+                "0:						\n\t"
+                "ldb    r1, @r0		; invalidate check	\n\t"
+                "bnez   r1, 0b					\n\t"
+                ";						\n\t"
+                "ldi    r0, #-1					\n\t"
+                "ldi    r1, #1					\n\t"
+                "stb    r1, @r0		; cache on		\n\t"
+		: : : "r0", "r1", "memory"
+	);
+	/* FIXME: copying-back d-cache and invalidating i-cache are needed.
+	 */
+#endif	/* CONFIG_CHIP_M32700 */
+}
+
+/* Embed a debug trap (TRAP1) code */
+static int
+embed_debug_trap(struct task_struct *child, unsigned long next_pc)
+{
+	unsigned long next_insn, code;
+	unsigned long addr = next_pc & ~3;
+
+	if (access_process_vm(child, addr, &next_insn, sizeof(next_insn), 0)
+	    != sizeof(next_insn)) {
+		return -1; /* error */
+	}
+
+	/* Set a trap code. */
+	if (register_debug_trap(child, next_pc, next_insn, &code)) {
+		return -1; /* error */
+	}
+	if (access_process_vm(child, addr, &code, sizeof(code), 1)
+	    != sizeof(code)) {
+		return -1; /* error */
+	}
+	return 0; /* success */
+}
+
+void
+withdraw_debug_trap(struct pt_regs *regs)
+{
+	unsigned long addr;
+	unsigned long code;
+
+ 	addr = (regs->bpc - 2) & ~3;
+	regs->bpc -= 2;
+	if (unregister_debug_trap(current, addr, &code)) {
+	    access_process_vm(current, addr, &code, sizeof(code), 1);
+	    invalidate_cache();
+	}
+}
+
+static void
+init_debug_traps(struct task_struct *child)
+{
+	struct debug_trap *p = &child->thread.debug_trap;
+	int i;
+	p->nr_trap = 0;
+	for (i = 0; i < MAX_TRAPS; i++) {
+		p->addr[i] = 0;
+		p->insn[i] = 0;
+	}
+}
+
+
+/*
+ * Called by kernel/ptrace.c when detaching..
+ *
+ * Make sure single step bits etc are not set.
+ */
+void ptrace_disable(struct task_struct *child)
+{
+	/* nothing to do.. */
+}
+
+static int
+do_ptrace(long request, struct task_struct *child, long addr, long data)
+{
+	unsigned long tmp;
+	int ret;
+
+	switch (request) {
+	/*
+	 * read word at location "addr" in the child process.
+	 */
+	case PTRACE_PEEKTEXT:
+	case PTRACE_PEEKDATA:
+		ret = access_process_vm(child, addr, &tmp, sizeof(tmp), 0);
+		if (ret == sizeof(tmp))
+			ret = put_user(tmp,(unsigned long __user *) data);
+		else
+			ret = -EIO;
+		break;
+
+	/*
+	 * read the word at location addr in the USER area.
+	 */
+	case PTRACE_PEEKUSR:
+		ret = ptrace_read_user(child, addr,
+				       (unsigned long __user *)data);
+		break;
+
+	/*
+	 * write the word at location addr.
+	 */
+	case PTRACE_POKETEXT:
+	case PTRACE_POKEDATA:
+		ret = access_process_vm(child, addr, &data, sizeof(data), 1);
+		if (ret == sizeof(data)) {
+			ret = 0;
+			if (request == PTRACE_POKETEXT) {
+				invalidate_cache();
+			}
+		} else {
+			ret = -EIO;
+		}
+		break;
+
+	/*
+	 * write the word at location addr in the USER area.
+	 */
+	case PTRACE_POKEUSR:
+		ret = ptrace_write_user(child, addr, data);
+		break;
+
+	/*
+	 * continue/restart and stop at next (return from) syscall
+	 */
+	case PTRACE_SYSCALL:
+	case PTRACE_CONT:
+		ret = -EIO;
+		if ((unsigned long) data > _NSIG)
+			break;
+		if (request == PTRACE_SYSCALL)
+			set_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
+		else
+			clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
+		child->exit_code = data;
+		wake_up_process(child);
+		ret = 0;
+		break;
+
+	/*
+	 * make the child exit.  Best I can do is send it a sigkill.
+	 * perhaps it should be put in the status that it wants to
+	 * exit.
+	 */
+	case PTRACE_KILL: {
+		ret = 0;
+		unregister_all_debug_traps(child);
+		invalidate_cache();
+		if (child->exit_state == EXIT_ZOMBIE)	/* already dead */
+			break;
+		child->exit_code = SIGKILL;
+		wake_up_process(child);
+		break;
+	}
+
+	/*
+	 * execute single instruction.
+	 */
+	case PTRACE_SINGLESTEP: {
+		unsigned long next_pc;
+		unsigned long pc, insn;
+
+		ret = -EIO;
+		if ((unsigned long) data > _NSIG)
+			break;
+		clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
+		if ((child->ptrace & PT_DTRACE) == 0) {
+			/* Spurious delayed TF traps may occur */
+			child->ptrace |= PT_DTRACE;
+		}
+
+		/* Compute next pc.  */
+		pc = get_stack_long(child, PT_BPC);
+
+		if (access_process_vm(child, pc&~3, &insn, sizeof(insn), 0)
+		    != sizeof(insn))
+			break;
+
+		compute_next_pc(insn, pc, &next_pc, child);
+		if (next_pc & 0x80000000)
+			break;
+
+		if (embed_debug_trap(child, next_pc))
+			break;
+
+		invalidate_cache();
+		child->exit_code = data;
+
+		/* give it a chance to run. */
+		wake_up_process(child);
+		ret = 0;
+		break;
+	}
+
+	/*
+	 * detach a process that was attached.
+	 */
+	case PTRACE_DETACH:
+		ret = 0;
+		ret = ptrace_detach(child, data);
+		break;
+
+	case PTRACE_GETREGS:
+		ret = ptrace_getregs(child, (void __user *)data);
+		break;
+
+	case PTRACE_SETREGS:
+		ret = ptrace_setregs(child, (void __user *)data);
+		break;
+
+	default:
+		ret = ptrace_request(child, request, addr, data);
+		break;
+	}
+
+	return ret;
+}
+
+asmlinkage int sys_ptrace(long request, long pid, long addr, long data)
+{
+	struct task_struct *child;
+	int ret;
+
+	lock_kernel();
+	ret = -EPERM;
+	if (request == PTRACE_TRACEME) {
+		/* are we already being traced? */
+		if (current->ptrace & PT_PTRACED)
+			goto out;
+		/* set the ptrace bit in the process flags. */
+		current->ptrace |= PT_PTRACED;
+		ret = 0;
+		goto out;
+	}
+	ret = -ESRCH;
+	read_lock(&tasklist_lock);
+	child = find_task_by_pid(pid);
+	if (child)
+		get_task_struct(child);
+	read_unlock(&tasklist_lock);
+	if (!child)
+		goto out;
+
+	ret = -EPERM;
+	if (pid == 1)		/* you may not mess with init */
+		goto out;
+
+	if (request == PTRACE_ATTACH) {
+		ret = ptrace_attach(child);
+		if (ret == 0)
+			init_debug_traps(child);
+		goto out_tsk;
+	}
+
+	ret = ptrace_check_attach(child, request == PTRACE_KILL);
+	if (ret == 0)
+		ret = do_ptrace(request, child, addr, data);
+
+out_tsk:
+	put_task_struct(child);
+out:
+	unlock_kernel();
+
+	return ret;
+}
+
+/* notification of system call entry/exit
+ * - triggered by current->work.syscall_trace
+ */
+void do_syscall_trace(void)
+{
+	if (!test_thread_flag(TIF_SYSCALL_TRACE))
+		return;
+	if (!(current->ptrace & PT_PTRACED))
+		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;
+	}
+}