[PATCH 6/14] h8300: use generic ptrace_resume code

From: Christoph Hellwig
Date: Tue Feb 02 2010 - 14:00:18 EST


Use the generic ptrace_resume code for PTRACE_SYSCALL, PTRACE_CONT,
PTRACE_KILL and PTRACE_SINGLESTEP. This implies defining
arch_has_single_step in <asm/ptrace.h> and implementing the
user_enable_single_step and user_disable_single_step functions, which
also causes the breakpoint information to be cleared on fork, which
could be considered a bug fix.

Also the TIF_SYSCALL_TRACE thread flag is now cleared on PTRACE_KILL
which it previously wasn't which is consistent with all architectures
using the modern ptrace code.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>


Index: linux-2.6/arch/h8300/kernel/ptrace.c
===================================================================
--- linux-2.6.orig/arch/h8300/kernel/ptrace.c 2010-02-02 11:01:22.072254015 +0100
+++ linux-2.6/arch/h8300/kernel/ptrace.c 2010-02-02 11:20:07.256255344 +0100
@@ -34,8 +34,11 @@
/* cpu depend functions */
extern long h8300_get_reg(struct task_struct *task, int regno);
extern int h8300_put_reg(struct task_struct *task, int regno, unsigned long data);
-extern void h8300_disable_trace(struct task_struct *child);
-extern void h8300_enable_trace(struct task_struct *child);
+
+
+void user_disable_single_step(struct task_struct *child)
+{
+}

/*
* does not yet catch signals sent when the child dies.
@@ -44,7 +47,7 @@ extern void h8300_enable_trace(struct ta

void ptrace_disable(struct task_struct *child)
{
- h8300_disable_trace(child);
+ user_disable_single_step(child);
}

long arch_ptrace(struct task_struct *child, long request, long addr, long data)
@@ -107,49 +110,6 @@ long arch_ptrace(struct task_struct *chi
}
ret = -EIO;
break ;
- case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */
- case PTRACE_CONT: { /* restart after signal. */
- ret = -EIO;
- if (!valid_signal(data))
- 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);
- /* make sure the single step bit is not set. */
- h8300_disable_trace(child);
- ret = 0;
- }
-
-/*
- * 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;
- h8300_disable_trace(child);
- wake_up_process(child);
- break;
- }
-
- case PTRACE_SINGLESTEP: { /* set the trap flag. */
- ret = -EIO;
- if (!valid_signal(data))
- break;
- clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
- child->exit_code = data;
- h8300_enable_trace(child);
- wake_up_process(child);
- ret = 0;
- break;
- }

case PTRACE_GETREGS: { /* Get all gp regs from the child. */
int i;
Index: linux-2.6/arch/h8300/platform/h8300h/ptrace_h8300h.c
===================================================================
--- linux-2.6.orig/arch/h8300/platform/h8300h/ptrace_h8300h.c 2010-02-02 11:00:49.957253800 +0100
+++ linux-2.6/arch/h8300/platform/h8300h/ptrace_h8300h.c 2010-02-02 11:19:15.327003827 +0100
@@ -60,7 +60,7 @@ int h8300_put_reg(struct task_struct *ta
}

/* disable singlestep */
-void h8300_disable_trace(struct task_struct *child)
+void user_disable_single_step(struct task_struct *child)
{
if((long)child->thread.breakinfo.addr != -1L) {
*child->thread.breakinfo.addr = child->thread.breakinfo.inst;
@@ -264,7 +264,7 @@ static unsigned short *getnextpc(struct

/* Set breakpoint(s) to simulate a single step from the current PC. */

-void h8300_enable_trace(struct task_struct *child)
+void user_enable_single_step(struct task_struct *child)
{
unsigned short *nextpc;
nextpc = getnextpc(child,(unsigned short *)h8300_get_reg(child, PT_PC));
@@ -276,7 +276,7 @@ void h8300_enable_trace(struct task_stru
asmlinkage void trace_trap(unsigned long bp)
{
if ((unsigned long)current->thread.breakinfo.addr == bp) {
- h8300_disable_trace(current);
+ user_disable_single_step(current);
force_sig(SIGTRAP,current);
} else
force_sig(SIGILL,current);
Index: linux-2.6/arch/h8300/platform/h8s/ptrace_h8s.c
===================================================================
--- linux-2.6.orig/arch/h8300/platform/h8s/ptrace_h8s.c 2010-02-02 11:00:49.968253944 +0100
+++ linux-2.6/arch/h8300/platform/h8s/ptrace_h8s.c 2010-02-02 11:19:15.329011624 +0100
@@ -65,13 +65,13 @@ int h8300_put_reg(struct task_struct *ta
}

/* disable singlestep */
-void h8300_disable_trace(struct task_struct *child)
+void user_disable_single_step(struct task_struct *child)
{
*(unsigned short *)(child->thread.esp0 + h8300_register_offset[PT_EXR]) &= ~EXR_TRACE;
}

/* enable singlestep */
-void h8300_enable_trace(struct task_struct *child)
+void user_enable_single_step(struct task_struct *child)
{
*(unsigned short *)(child->thread.esp0 + h8300_register_offset[PT_EXR]) |= EXR_TRACE;
}
Index: linux-2.6/arch/h8300/include/asm/ptrace.h
===================================================================
--- linux-2.6.orig/arch/h8300/include/asm/ptrace.h 2010-02-02 11:19:24.753253118 +0100
+++ linux-2.6/arch/h8300/include/asm/ptrace.h 2010-02-02 11:19:36.822033076 +0100
@@ -55,6 +55,8 @@ struct pt_regs {
/* Find the stack offset for a register, relative to thread.esp0. */
#define PT_REG(reg) ((long)&((struct pt_regs *)0)->reg)

+#define arch_has_single_step() (1)
+
#define user_mode(regs) (!((regs)->ccr & PS_S))
#define instruction_pointer(regs) ((regs)->pc)
#define profile_pc(regs) instruction_pointer(regs)
--
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