lkml.org 
[lkml]   [2007]   [Nov]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 16/27] x86-64 ptrace: use task_pt_regs
Date

This cleans up the 64-bit ptrace code to use task_pt_regs instead of its
own redundant code that does the same thing a different way.

Signed-off-by: Roland McGrath <roland@redhat.com>
---
arch/x86/kernel/ptrace_64.c | 60 ++++++++----------------------------------
1 files changed, 12 insertions(+), 48 deletions(-)
diff --git a/arch/x86/kernel/ptrace_64.c b/arch/x86/kernel/ptrace_64.c
index 85fba7b..8123ecb 100644
--- a/arch/x86/kernel/ptrace_64.c
+++ b/arch/x86/kernel/ptrace_64.c
@@ -43,44 +43,6 @@
#define FLAG_MASK 0x54dd5UL

/*
- * eflags and offset of eflags on child stack..
- */
-#define EFLAGS offsetof(struct pt_regs, eflags)
-#define EFL_OFFSET ((int)(EFLAGS-sizeof(struct pt_regs)))
-
-/*
- * this routine will get a word off of the processes privileged stack.
- * the offset is how far from the base addr as stored in the TSS.
- * this routine assumes that all the privileged stacks are in our
- * data space.
- */
-static inline unsigned long get_stack_long(struct task_struct *task, int offset)
-{
- unsigned char *stack;
-
- stack = (unsigned char *)task->thread.rsp0;
- stack += offset;
- return (*((unsigned long *)stack));
-}
-
-/*
- * this routine will put a word on the processes privileged stack.
- * the offset is how far from the base addr as stored in the TSS.
- * this routine assumes that all the privileged stacks are in our
- * data space.
- */
-static inline long put_stack_long(struct task_struct *task, int offset,
- unsigned long data)
-{
- unsigned char * stack;
-
- stack = (unsigned char *) task->thread.rsp0;
- stack += offset;
- *(unsigned long *) stack = data;
- return 0;
-}
-
-/*
* Called by kernel/ptrace.c when detaching..
*
* Make sure the single step bit is not set.
@@ -90,11 +52,16 @@ void ptrace_disable(struct task_struct *child)
user_disable_single_step(child);
}

+static unsigned long *pt_regs_access(struct pt_regs *regs, unsigned long offset)
+{
+ BUILD_BUG_ON(offsetof(struct pt_regs, r15) != 0);
+ return &regs->r15 + (offset / sizeof(regs->r15));
+}
+
static int putreg(struct task_struct *child,
unsigned long regno, unsigned long value)
{
- unsigned long tmp;
-
+ struct pt_regs *regs = task_pt_regs(child);
switch (regno) {
case offsetof(struct user_regs_struct,fs):
if (value && (value & 3) != 3)
@@ -152,9 +119,7 @@ static int putreg(struct task_struct *child,
clear_tsk_thread_flag(child, TIF_FORCED_TF);
else if (test_tsk_thread_flag(child, TIF_FORCED_TF))
value |= X86_EFLAGS_TF;
- tmp = get_stack_long(child, EFL_OFFSET);
- tmp &= ~FLAG_MASK;
- value |= tmp;
+ value |= regs->eflags & ~FLAG_MASK;
break;
case offsetof(struct user_regs_struct,cs):
if ((value & 3) != 3)
@@ -162,12 +127,13 @@ static int putreg(struct task_struct *child,
value &= 0xffff;
break;
}
- put_stack_long(child, regno - sizeof(struct pt_regs), value);
+ *pt_regs_access(regs, regno) = value;
return 0;
}

static unsigned long getreg(struct task_struct *child, unsigned long regno)
{
+ struct pt_regs *regs = task_pt_regs(child);
unsigned long val;
switch (regno) {
case offsetof(struct user_regs_struct, fs):
@@ -202,16 +168,14 @@ static unsigned long getreg(struct task_struct *child, unsigned long regno)
/*
* If the debugger set TF, hide it from the readout.
*/
- regno = regno - sizeof(struct pt_regs);
- val = get_stack_long(child, regno);
+ val = regs->eflags;
if (test_tsk_thread_flag(child, TIF_IA32))
val &= 0xffffffff;
if (test_tsk_thread_flag(child, TIF_FORCED_TF))
val &= ~X86_EFLAGS_TF;
return val;
default:
- regno = regno - sizeof(struct pt_regs);
- val = get_stack_long(child, regno);
+ val = *pt_regs_access(regs, regno);
if (test_tsk_thread_flag(child, TIF_IA32))
val &= 0xffffffff;
return val;
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
\
 
 \ /
  Last update: 2007-11-25 23:09    [from the cache]
©2003-2014 Jasper Spaans. Advertise on this site