[PATCH] uml: S390 preparation, peekusr/pokeusr defined by subarch
s390 needs to change some parts of arch/um/kernel/ptrace.c. Thus, the code
regarding PEEKUSER and POKEUSER are shifted to arch/um/sys-<subarch>/ptrace.c.
Also s390 debug registers need to be updated, when singlestepping is switched
on / off. Thus, setting/resetting of singlestepping is centralized in the new
function set_singlestep(), which also inserts the macro
SUBARCH_SET_SINGLESTEP(mode), if defined.
Finally, s390 has the "ieee_instruction_pointer" in its
registers, which also is allowed to be read via
ptrace( PTRACE_PEEKUSER, getpid(), PT_IEEE_IP, 0);
To implement this feature, sys_ptrace inserts the macro
SUBARCH_PTRACE_SPECIAL, if defined.
Signed-off-by: Bodo Stroesser <bstroesser@fujitsu-siemens.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/arch/um/kernel/ptrace.c b/arch/um/kernel/ptrace.c
index 3efa59a..2b75d8d 100644
--- a/arch/um/kernel/ptrace.c
+++ b/arch/um/kernel/ptrace.c
@@ -19,15 +19,30 @@
#include "skas_ptrace.h"
#include "sysdep/ptrace.h"
+static inline void set_singlestepping(struct task_struct *child, int on)
+{
+ if (on)
+ child->ptrace |= PT_DTRACE;
+ else
+ child->ptrace &= ~PT_DTRACE;
+ child->thread.singlestep_syscall = 0;
+
+#ifdef SUBARCH_SET_SINGLESTEPPING
+ SUBARCH_SET_SINGLESTEPPING(child, on)
+#endif
+ }
+
/*
* Called by kernel/ptrace.c when detaching..
*/
void ptrace_disable(struct task_struct *child)
{
- child->ptrace &= ~PT_DTRACE;
- child->thread.singlestep_syscall = 0;
+ set_singlestepping(child,0);
}
+extern int peek_user(struct task_struct * child, long addr, long data);
+extern int poke_user(struct task_struct * child, long addr, long data);
+
long sys_ptrace(long request, long pid, long addr, long data)
{
struct task_struct *child;
@@ -67,6 +82,10 @@
goto out_tsk;
}
+#ifdef SUBACH_PTRACE_SPECIAL
+ SUBARCH_PTRACE_SPECIAL(child,request,addr,data)
+#endif
+
ret = ptrace_check_attach(child, request == PTRACE_KILL);
if (ret < 0)
goto out_tsk;
@@ -87,28 +106,9 @@
}
/* read the word at location addr in the USER area. */
- case PTRACE_PEEKUSR: {
- unsigned long tmp;
-
- ret = -EIO;
- if ((addr & 3) || addr < 0)
- break;
-
- tmp = 0; /* Default return condition */
- if(addr < MAX_REG_OFFSET){
- tmp = getreg(child, addr);
- }
-#if defined(CONFIG_UML_X86) && !defined(CONFIG_64BIT)
- else if((addr >= offsetof(struct user, u_debugreg[0])) &&
- (addr <= offsetof(struct user, u_debugreg[7]))){
- addr -= offsetof(struct user, u_debugreg[0]);
- addr = addr >> 2;
- tmp = child->thread.arch.debugregs[addr];
- }
-#endif
- ret = put_user(tmp, (unsigned long __user *) data);
- break;
- }
+ case PTRACE_PEEKUSR:
+ ret = peek_user(child, addr, data);
+ break;
/* when I and D space are separate, this will have to be fixed. */
case PTRACE_POKETEXT: /* write the word at location addr. */
@@ -121,26 +121,8 @@
break;
case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
- ret = -EIO;
- if ((addr & 3) || addr < 0)
- break;
-
- if (addr < MAX_REG_OFFSET) {
- ret = putreg(child, addr, data);
- break;
- }
-#if defined(CONFIG_UML_X86) && !defined(CONFIG_64BIT)
- else if((addr >= offsetof(struct user, u_debugreg[0])) &&
- (addr <= offsetof(struct user, u_debugreg[7]))){
- addr -= offsetof(struct user, u_debugreg[0]);
- addr = addr >> 2;
- if((addr == 4) || (addr == 5)) break;
- child->thread.arch.debugregs[addr] = data;
- ret = 0;
- }
-#endif
-
- break;
+ ret = poke_user(child, addr, data);
+ break;
case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */
case PTRACE_CONT: { /* restart after signal. */
@@ -148,8 +130,7 @@
if (!valid_signal(data))
break;
- child->ptrace &= ~PT_DTRACE;
- child->thread.singlestep_syscall = 0;
+ set_singlestepping(child, 0);
if (request == PTRACE_SYSCALL) {
set_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
}
@@ -172,8 +153,7 @@
if (child->exit_state == EXIT_ZOMBIE) /* already dead */
break;
- child->ptrace &= ~PT_DTRACE;
- child->thread.singlestep_syscall = 0;
+ set_singlestepping(child, 0);
child->exit_code = SIGKILL;
wake_up_process(child);
break;
@@ -184,8 +164,7 @@
if (!valid_signal(data))
break;
clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
- child->ptrace |= PT_DTRACE;
- child->thread.singlestep_syscall = 0;
+ set_singlestepping(child, 1);
child->exit_code = data;
/* give it a chance to run. */
wake_up_process(child);