2010-02-16 00:30:32

by Mike Frysinger

Subject: [PATCH] ptrace: unify FDPIC implementations

The Blackfin/FRV/SuperH guys all have the same exact FDPIC ptrace code in
their arch handlers (since they were probably copied & pasted). Since
these ptrace interfaces are an arch independent aspect of the FDPIC code,
unify them in the common ptrace code so new FDPIC ports don't need to copy
and paste this fundamental stuff yet again.

Signed-off-by: Mike Frysinger <[email protected]>
Acked-by: Roland McGrath <[email protected]>
Acked-by: David Howells <[email protected]>
Acked-by: Paul Mundt <[email protected]>
---
Andrew: could you pick this up ? everyone concerned has acked it ...

arch/blackfin/kernel/ptrace.c | 33 ++++++++-------------------------
arch/frv/kernel/ptrace.c | 20 --------------------
arch/sh/kernel/ptrace_32.c | 23 -----------------------
kernel/ptrace.c | 20 ++++++++++++++++++++
4 files changed, 28 insertions(+), 68 deletions(-)

diff --git a/arch/blackfin/kernel/ptrace.c b/arch/blackfin/kernel/ptrace.c
index 65567dc..0ae2f1e 100644
--- a/arch/blackfin/kernel/ptrace.c
+++ b/arch/blackfin/kernel/ptrace.c
@@ -261,11 +261,15 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
} else if (addr == (sizeof(struct pt_regs) + 8)) {
/* PT_DATA_ADDR */
tmp = child->mm->start_data;
-#ifdef CONFIG_BINFMT_ELF_FDPIC
+#ifdef CONFIG_BINFMT_ELF_FDPIC /* backwards compat */
} else if (addr == (sizeof(struct pt_regs) + 12)) {
- goto case_PTRACE_GETFDPIC_EXEC;
+ request = PTRACE_GETFDPIC;
+ addr = PTRACE_GETFDPIC_EXEC;
+ goto case_default;
} else if (addr == (sizeof(struct pt_regs) + 16)) {
- goto case_PTRACE_GETFDPIC_INTERP;
+ request = PTRACE_GETFDPIC;
+ addr = PTRACE_GETFDPIC_INTERP;
+ goto case_default;
#endif
} else {
tmp = get_reg(child, addr);
@@ -274,28 +278,6 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
break;
}

-#ifdef CONFIG_BINFMT_ELF_FDPIC
- case PTRACE_GETFDPIC: {
- unsigned long tmp = 0;
-
- switch (addr) {
- case_PTRACE_GETFDPIC_EXEC:
- case PTRACE_GETFDPIC_EXEC:
- tmp = child->mm->context.exec_fdpic_loadmap;
- break;
- case_PTRACE_GETFDPIC_INTERP:
- case PTRACE_GETFDPIC_INTERP:
- tmp = child->mm->context.interp_fdpic_loadmap;
- break;
- default:
- break;
- }
-
- ret = put_user(tmp, datap);
- break;
- }
-#endif
-
/* when I and D space are separate, this will have to be fixed. */
case PTRACE_POKEDATA:
pr_debug("ptrace: PTRACE_PEEKDATA\n");
@@ -409,6 +391,7 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
ret = 0;
break;

+ case_default:
default:
ret = ptrace_request(child, request, addr, data);
break;
diff --git a/arch/frv/kernel/ptrace.c b/arch/frv/kernel/ptrace.c
index 60eeed3..fac0289 100644
--- a/arch/frv/kernel/ptrace.c
+++ b/arch/frv/kernel/ptrace.c
@@ -344,26 +344,6 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
0, sizeof(child->thread.user->f),
(const void __user *)data);

- case PTRACE_GETFDPIC:
- tmp = 0;
- switch (addr) {
- case PTRACE_GETFDPIC_EXEC:
- tmp = child->mm->context.exec_fdpic_loadmap;
- break;
- case PTRACE_GETFDPIC_INTERP:
- tmp = child->mm->context.interp_fdpic_loadmap;
- break;
- default:
- break;
- }
-
- ret = 0;
- if (put_user(tmp, (unsigned long *) data)) {
- ret = -EFAULT;
- break;
- }
- break;
-
default:
ret = ptrace_request(child, request, addr, data);
break;
diff --git a/arch/sh/kernel/ptrace_32.c b/arch/sh/kernel/ptrace_32.c
index 9be35f3..ab8123b 100644
--- a/arch/sh/kernel/ptrace_32.c
+++ b/arch/sh/kernel/ptrace_32.c
@@ -405,29 +405,6 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
0, sizeof(struct pt_dspregs),
(const void __user *)data);
#endif
-#ifdef CONFIG_BINFMT_ELF_FDPIC
- case PTRACE_GETFDPIC: {
- unsigned long tmp = 0;
-
- switch (addr) {
- case PTRACE_GETFDPIC_EXEC:
- tmp = child->mm->context.exec_fdpic_loadmap;
- break;
- case PTRACE_GETFDPIC_INTERP:
- tmp = child->mm->context.interp_fdpic_loadmap;
- break;
- default:
- break;
- }
-
- ret = 0;
- if (put_user(tmp, datap)) {
- ret = -EFAULT;
- break;
- }
- break;
- }
-#endif
default:
ret = ptrace_request(child, request, addr, data);
break;
diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index 23bd09c..60fe465 100644
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -554,6 +554,26 @@ int ptrace_request(struct task_struct *child, long request,
ret = ptrace_detach(child, data);
break;

+#ifdef CONFIG_BINFMT_ELF_FDPIC
+ case PTRACE_GETFDPIC: {
+ unsigned long tmp = 0;
+
+ switch (addr) {
+ case PTRACE_GETFDPIC_EXEC:
+ tmp = child->mm->context.exec_fdpic_loadmap;
+ break;
+ case PTRACE_GETFDPIC_INTERP:
+ tmp = child->mm->context.interp_fdpic_loadmap;
+ break;
+ default:
+ break;
+ }
+
+ ret = put_user(tmp, (unsigned long __user *) data);
+ break;
+ }
+#endif
+
#ifdef PTRACE_SINGLESTEP
case PTRACE_SINGLESTEP:
#endif
--
1.7.0

2010-02-16 01:10:56

by Paul Mundt

Subject: Re: [PATCH] ptrace: unify FDPIC implementations

On Mon, Feb 15, 2010 at 07:30:29PM -0500, Mike Frysinger wrote:
> The Blackfin/FRV/SuperH guys all have the same exact FDPIC ptrace code in
> their arch handlers (since they were probably copied & pasted). Since
> these ptrace interfaces are an arch independent aspect of the FDPIC code,
> unify them in the common ptrace code so new FDPIC ports don't need to copy
> and paste this fundamental stuff yet again.
>
> Signed-off-by: Mike Frysinger <[email protected]>
> Acked-by: Roland McGrath <[email protected]>
> Acked-by: David Howells <[email protected]>
> Acked-by: Paul Mundt <[email protected]>

Just to follow up on this, this code obviously expects consistent entries
in mm_context_t. Presently include/asm-generic/mmu.h is aimed at nommu,
so it would probably be worthwhile stubbing in the FDPIC loadmap entries
there to make things easier for future ports.

2010-02-16 08:12:31

by Mike Frysinger

Subject: Re: [PATCH] ptrace: unify FDPIC implementations

On Mon, Feb 15, 2010 at 20:10, Paul Mundt wrote:
> On Mon, Feb 15, 2010 at 07:30:29PM -0500, Mike Frysinger wrote:
>> The Blackfin/FRV/SuperH guys all have the same exact FDPIC ptrace code in
>> their arch handlers (since they were probably copied & pasted).  Since
>> these ptrace interfaces are an arch independent aspect of the FDPIC code,
>> unify them in the common ptrace code so new FDPIC ports don't need to copy
>> and paste this fundamental stuff yet again.
>>
>> Signed-off-by: Mike Frysinger <[email protected]>
>> Acked-by: Roland McGrath <[email protected]>
>> Acked-by: David Howells <[email protected]>
>> Acked-by: Paul Mundt <[email protected]>
>
> Just to follow up on this, this code obviously expects consistent entries
> in mm_context_t. Presently include/asm-generic/mmu.h is aimed at nommu,
> so it would probably be worthwhile stubbing in the FDPIC loadmap entries
> there to make things easier for future ports.

probably be a good idea. for FDPIC in general, the header also needs
"stack_start".
-mike