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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/sh/kernel/ptrace.c
downloadlinux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz
Linux-2.6.12-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!
Diffstat (limited to 'arch/sh/kernel/ptrace.c')
-rw-r--r--arch/sh/kernel/ptrace.c320
1 files changed, 320 insertions, 0 deletions
diff --git a/arch/sh/kernel/ptrace.c b/arch/sh/kernel/ptrace.c
new file mode 100644
index 000000000000..1b0dfb4d8ea4
--- /dev/null
+++ b/arch/sh/kernel/ptrace.c
@@ -0,0 +1,320 @@
+/*
+ * linux/arch/sh/kernel/ptrace.c
+ *
+ * Original x86 implementation:
+ *	By Ross Biro 1/23/92
+ *	edited by Linus Torvalds
+ *
+ * SuperH version:   Copyright (C) 1999, 2000  Kaz Kojima & Niibe Yutaka
+ *
+ */
+
+#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/slab.h>
+#include <linux/security.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>
+
+/*
+ * does not yet catch signals sent when the child dies.
+ * in exit.c or in signal.c.
+ */
+
+/*
+ * This routine will get a word off of the process kernel stack.
+ */
+static inline int get_stack_long(struct task_struct *task, int offset)
+{
+	unsigned char *stack;
+
+	stack = (unsigned char *)
+		task->thread_info + THREAD_SIZE	- sizeof(struct pt_regs)
+#ifdef CONFIG_SH_DSP
+		- sizeof(struct pt_dspregs)
+#endif
+		- sizeof(unsigned long);
+	stack += offset;
+	return (*((int *)stack));
+}
+
+/*
+ * 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 char *stack;
+
+	stack = (unsigned char *)
+		task->thread_info + THREAD_SIZE - sizeof(struct pt_regs)
+#ifdef CONFIG_SH_DSP
+		- sizeof(struct pt_dspregs)
+#endif
+		- sizeof(unsigned long);
+	stack += offset;
+	*(unsigned long *) stack = data;
+	return 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.. */
+}
+
+asmlinkage int sys_ptrace(long request, long pid, long addr, long data)
+{
+	struct task_struct *child;
+	struct user * dummy = NULL;
+	int ret;
+
+	lock_kernel();
+	ret = -EPERM;
+	if (request == PTRACE_TRACEME) {
+		/* are we already being traced? */
+		if (current->ptrace & PT_PTRACED)
+			goto out;
+		ret = security_ptrace(current->parent, current);
+		if (ret)
+			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_tsk;
+
+	if (request == PTRACE_ATTACH) {
+		ret = ptrace_attach(child);
+		goto out_tsk;
+	}
+
+	ret = ptrace_check_attach(child, request == PTRACE_KILL);
+	if (ret < 0)
+		goto out_tsk;
+
+	switch (request) {
+	/* when I and D space are separate, these will need to be fixed. */
+	case PTRACE_PEEKTEXT: /* read word at location addr. */ 
+	case PTRACE_PEEKDATA: {
+		unsigned long tmp;
+		int copied;
+
+		copied = access_process_vm(child, addr, &tmp, sizeof(tmp), 0);
+		ret = -EIO;
+		if (copied != sizeof(tmp))
+			break;
+		ret = put_user(tmp,(unsigned long *) data);
+		break;
+	}
+
+	/* read the word at location addr in the USER area. */
+	case PTRACE_PEEKUSR: {
+		unsigned long tmp;
+
+		ret = -EIO;
+		if ((addr & 3) || addr < 0 || 
+		    addr > sizeof(struct user) - 3)
+			break;
+
+		if (addr < sizeof(struct pt_regs))
+			tmp = get_stack_long(child, addr);
+		else if (addr >= (long) &dummy->fpu &&
+			 addr < (long) &dummy->u_fpvalid) {
+			if (!tsk_used_math(child)) {
+				if (addr == (long)&dummy->fpu.fpscr)
+					tmp = FPSCR_INIT;
+				else
+					tmp = 0;
+			} else
+				tmp = ((long *)&child->thread.fpu)
+					[(addr - (long)&dummy->fpu) >> 2];
+		} else if (addr == (long) &dummy->u_fpvalid)
+			tmp = !!tsk_used_math(child);
+		else
+			tmp = 0;
+		ret = put_user(tmp, (unsigned long *)data);
+		break;
+	}
+
+	/* when I and D space are separate, this will have to be fixed. */
+	case PTRACE_POKETEXT: /* write the word at location addr. */
+	case PTRACE_POKEDATA:
+		ret = 0;
+		if (access_process_vm(child, addr, &data, sizeof(data), 1) == sizeof(data))
+			break;
+		ret = -EIO;
+		break;
+
+	case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
+		ret = -EIO;
+		if ((addr & 3) || addr < 0 || 
+		    addr > sizeof(struct user) - 3)
+			break;
+
+		if (addr < sizeof(struct pt_regs))
+			ret = put_stack_long(child, addr, data);
+		else if (addr >= (long) &dummy->fpu &&
+			 addr < (long) &dummy->u_fpvalid) {
+			set_stopped_child_used_math(child);
+			((long *)&child->thread.fpu)
+				[(addr - (long)&dummy->fpu) >> 2] = data;
+			ret = 0;
+		} else if (addr == (long) &dummy->u_fpvalid) {
+			conditional_stopped_child_used_math(data, child);
+			ret = 0;
+		}
+		break;
+
+	case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */
+	case PTRACE_CONT: { /* restart after signal. */
+		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;
+		if (child->exit_state == EXIT_ZOMBIE)	/* already dead */
+			break;
+		child->exit_code = SIGKILL;
+		wake_up_process(child);
+		break;
+	}
+
+	case PTRACE_SINGLESTEP: {  /* set the trap flag. */
+		long pc;
+		struct pt_regs *dummy = NULL;
+
+		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;
+		}
+
+		pc = get_stack_long(child, (long)&dummy->pc);
+
+		/* Next scheduling will set up UBC */
+		if (child->thread.ubc_pc == 0)
+			ubc_usercnt += 1;
+		child->thread.ubc_pc = pc;
+
+		child->exit_code = data;
+		/* give it a chance to run. */
+		wake_up_process(child);
+		ret = 0;
+		break;
+	}
+
+	case PTRACE_DETACH: /* detach a process that was attached. */
+		ret = ptrace_detach(child, data);
+		break;
+
+#ifdef CONFIG_SH_DSP
+	case PTRACE_GETDSPREGS: {
+		unsigned long dp;
+
+		ret = -EIO;
+		dp = ((unsigned long) child) + THREAD_SIZE -
+			 sizeof(struct pt_dspregs);
+		if (*((int *) (dp - 4)) == SR_FD) {
+			copy_to_user(addr, (void *) dp,
+				sizeof(struct pt_dspregs));
+			ret = 0;
+		}
+		break;
+	}
+
+	case PTRACE_SETDSPREGS: {
+		unsigned long dp;
+		int i;
+
+		ret = -EIO;
+		dp = ((unsigned long) child) + THREAD_SIZE -
+			 sizeof(struct pt_dspregs);
+		if (*((int *) (dp - 4)) == SR_FD) {
+			copy_from_user((void *) dp, addr,
+				sizeof(struct pt_dspregs));
+			ret = 0;
+		}
+		break;
+	}
+#endif
+	default:
+		ret = ptrace_request(child, request, addr, data);
+		break;
+	}
+out_tsk:
+	put_task_struct(child);
+out:
+	unlock_kernel();
+	return ret;
+}
+
+asmlinkage void do_syscall_trace(void)
+{
+	struct task_struct *tsk = current;
+
+	if (!test_thread_flag(TIF_SYSCALL_TRACE))
+		return;
+	if (!(tsk->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 (tsk->exit_code) {
+		send_sig(tsk->exit_code, tsk, 1);
+		tsk->exit_code = 0;
+	}
+}