[POWERPC] ptrace cleanups

The powerpc ptrace code has some weirdness, like a ptrace-common.h file that
is actually ppc64 only and some of the 32 bits code ifdef'ed inside ptrace.c.

There are also separate implementations for things like get/set_vrregs for
32 and 64 bits which is totally unnecessary.

This patch cleans that up a bit by having a ptrace-common.h which contains
really common code (and makes a lot more code common), and ptrace-ppc32.h and
ptrace-ppc64.h files that contain the few remaining different bits.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

5 files changed, 197 insertions, 242 deletions

diff --git a/arch/powerpc/kernel/ptrace-common.h b/arch/powerpc/kernel/ptrace-common.h
index 8797ae737a7b..f0746eca8f44 100644
--- a/arch/powerpc/kernel/ptrace-common.h
+++ b/arch/powerpc/kernel/ptrace-common.h
@@ -1,5 +1,6 @@
 /*
  *    Copyright (c) 2002 Stephen Rothwell, IBM Coproration
+ *    Copyright (c) 2007 Benjamin Herrenschmidt, IBM Coproration
  *    Extracted from ptrace.c and ptrace32.c
  *
  * This file is subject to the terms and conditions of the GNU General
@@ -7,15 +8,8 @@
  * this archive for more details.
  */
 
-#ifndef _PPC64_PTRACE_COMMON_H
-#define _PPC64_PTRACE_COMMON_H
-
-#include <asm/system.h>
-
-/*
- * Set of msr bits that gdb can change on behalf of a process.
- */
-#define MSR_DEBUGCHANGE (MSR_FE0 | MSR_SE | MSR_BE | MSR_FE1)
+#ifndef _POWERPC_PTRACE_COMMON_H
+#define _POWERPC_PTRACE_COMMON_H
 
 /*
  * Get contents of register REGNO in task TASK.
@@ -24,18 +18,18 @@ static inline unsigned long get_reg(struct task_struct *task, int regno)
 {
         unsigned long tmp = 0;
 
-        /*
-         * Put the correct FP bits in, they might be wrong as a result
-         * of our lazy FP restore.
-         */
+        if (task->thread.regs == NULL)
+                return -EIO;
+
         if (regno == PT_MSR) {
                 tmp = ((unsigned long *)task->thread.regs)[PT_MSR];
-                tmp |= task->thread.fpexc_mode;
-        } else if (regno < (sizeof(struct pt_regs) / sizeof(unsigned long))) {
-                tmp = ((unsigned long *)task->thread.regs)[regno];
+                return PT_MUNGE_MSR(tmp, task);
         }
 
-        return tmp;
+        if (regno < (sizeof(struct pt_regs) / sizeof(unsigned long)))
+                return ((unsigned long *)task->thread.regs)[regno];
+
+        return -EIO;
 }
 
 /*
@@ -44,7 +38,10 @@ static inline unsigned long get_reg(struct task_struct *task, int regno)
 static inline int put_reg(struct task_struct *task, int regno,
                           unsigned long data)
 {
-        if (regno < PT_SOFTE) {
+        if (task->thread.regs == NULL)
+                return -EIO;
+
+        if (regno <= PT_MAX_PUT_REG) {
                 if (regno == PT_MSR)
                         data = (data & MSR_DEBUGCHANGE)
                                 | (task->thread.regs->msr & ~MSR_DEBUGCHANGE);
@@ -54,21 +51,6 @@ static inline int put_reg(struct task_struct *task, int regno,
         return -EIO;
 }
 
-static inline void set_single_step(struct task_struct *task)
-{
-        struct pt_regs *regs = task->thread.regs;
-        if (regs != NULL)
-                regs->msr |= MSR_SE;
-        set_tsk_thread_flag(task, TIF_SINGLESTEP);
-}
-
-static inline void clear_single_step(struct task_struct *task)
-{
-        struct pt_regs *regs = task->thread.regs;
-        if (regs != NULL)
-                regs->msr &= ~MSR_SE;
-        clear_tsk_thread_flag(task, TIF_SINGLESTEP);
-}
 
 #ifdef CONFIG_ALTIVEC
 /*
@@ -137,25 +119,36 @@ static inline int set_vrregs(struct task_struct *task,
 
         return 0;
 }
-#endif
+#endif /* CONFIG_ALTIVEC */
 
-static inline int ptrace_set_debugreg(struct task_struct *task,
-                                      unsigned long addr, unsigned long data)
+static inline void set_single_step(struct task_struct *task)
 {
-        /* We only support one DABR and no IABRS at the moment */
-        if (addr > 0)
-                return -EINVAL;
+        struct pt_regs *regs = task->thread.regs;
 
-        /* The bottom 3 bits are flags */
-        if ((data & ~0x7UL) >= TASK_SIZE)
-                return -EIO;
+        if (regs != NULL) {
+#if defined(CONFIG_40x) || defined(CONFIG_BOOKE)
+                task->thread.dbcr0 = DBCR0_IDM | DBCR0_IC;
+                regs->msr |= MSR_DE;
+#else
+                regs->msr |= MSR_SE;
+#endif
+        }
+        set_tsk_thread_flag(task, TIF_SINGLESTEP);
+}
 
-        /* Ensure translation is on */
-        if (data && !(data & DABR_TRANSLATION))
-                return -EIO;
+static inline void clear_single_step(struct task_struct *task)
+{
+        struct pt_regs *regs = task->thread.regs;
 
-        task->thread.dabr = data;
-        return 0;
+        if (regs != NULL) {
+#if defined(CONFIG_40x) || defined(CONFIG_BOOKE)
+                task->thread.dbcr0 = 0;
+                regs->msr &= ~MSR_DE;
+#else
+                regs->msr &= ~MSR_SE;
+#endif
+        }
+        clear_tsk_thread_flag(task, TIF_SINGLESTEP);
 }
 
-#endif /* _PPC64_PTRACE_COMMON_H */
+#endif /* _POWERPC_PTRACE_COMMON_H */
diff --git a/arch/powerpc/kernel/ptrace-ppc32.h b/arch/powerpc/kernel/ptrace-ppc32.h
new file mode 100644
index 000000000000..24d7a2f680af
--- /dev/null
+++ b/arch/powerpc/kernel/ptrace-ppc32.h
@@ -0,0 +1,100 @@
+/*
+ *    Copyright (c) 2007 Benjamin Herrenschmidt, IBM Coproration
+ *    Extracted from ptrace.c and ptrace32.c
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License.  See the file README.legal in the main directory of
+ * this archive for more details.
+ */
+
+#ifndef _POWERPC_PTRACE_PPC32_H
+#define _POWERPC_PTRACE_PPC32_H
+
+/*
+ * Set of msr bits that gdb can change on behalf of a process.
+ */
+#if defined(CONFIG_40x) || defined(CONFIG_BOOKE)
+#define MSR_DEBUGCHANGE 0
+#else
+#define MSR_DEBUGCHANGE (MSR_SE | MSR_BE)
+#endif
+
+/*
+ * Max register writeable via put_reg
+ */
+#define PT_MAX_PUT_REG  PT_MQ
+
+/*
+ * Munging of MSR on return from get_regs
+ *
+ * Nothing to do on ppc32
+ */
+#define PT_MUNGE_MSR(msr, task) (msr)
+
+
+#ifdef CONFIG_SPE
+
+/*
+ * For get_evrregs/set_evrregs functions 'data' has the following layout:
+ *
+ * struct {
+ *   u32 evr[32];
+ *   u64 acc;
+ *   u32 spefscr;
+ * }
+ */
+
+/*
+ * Get contents of SPE register state in task TASK.
+ */
+static inline int get_evrregs(unsigned long *data, struct task_struct *task)
+{
+        int i;
+
+        if (!access_ok(VERIFY_WRITE, data, 35 * sizeof(unsigned long)))
+                return -EFAULT;
+
+        /* copy SPEFSCR */
+        if (__put_user(task->thread.spefscr, &data[34]))
+                return -EFAULT;
+
+        /* copy SPE registers EVR[0] .. EVR[31] */
+        for (i = 0; i < 32; i++, data++)
+                if (__put_user(task->thread.evr[i], data))
+                        return -EFAULT;
+
+        /* copy ACC */
+        if (__put_user64(task->thread.acc, (unsigned long long *)data))
+                return -EFAULT;
+
+        return 0;
+}
+
+/*
+ * Write contents of SPE register state into task TASK.
+ */
+static inline int set_evrregs(struct task_struct *task, unsigned long *data)
+{
+        int i;
+
+        if (!access_ok(VERIFY_READ, data, 35 * sizeof(unsigned long)))
+                return -EFAULT;
+
+        /* copy SPEFSCR */
+        if (__get_user(task->thread.spefscr, &data[34]))
+                return -EFAULT;
+
+        /* copy SPE registers EVR[0] .. EVR[31] */
+        for (i = 0; i < 32; i++, data++)
+                if (__get_user(task->thread.evr[i], data))
+                        return -EFAULT;
+        /* copy ACC */
+        if (__get_user64(task->thread.acc, (unsigned long long*)data))
+                return -EFAULT;
+
+        return 0;
+}
+#endif /* CONFIG_SPE */
+
+
+#endif /* _POWERPC_PTRACE_PPC32_H */
diff --git a/arch/powerpc/kernel/ptrace-ppc64.h b/arch/powerpc/kernel/ptrace-ppc64.h
new file mode 100644
index 000000000000..e450ce01392b
--- /dev/null
+++ b/arch/powerpc/kernel/ptrace-ppc64.h
@@ -0,0 +1,51 @@
+/*
+ *    Copyright (c) 2002 Stephen Rothwell, IBM Coproration
+ *    Extracted from ptrace.c and ptrace32.c
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License.  See the file README.legal in the main directory of
+ * this archive for more details.
+ */
+
+#ifndef _POWERPC_PTRACE_PPC64_H
+#define _POWERPC_PTRACE_PPC64_H
+
+/*
+ * Set of msr bits that gdb can change on behalf of a process.
+ */
+#define MSR_DEBUGCHANGE (MSR_FE0 | MSR_SE | MSR_BE | MSR_FE1)
+
+/*
+ * Max register writeable via put_reg
+ */
+#define PT_MAX_PUT_REG  PT_CCR
+
+/*
+ * Munging of MSR on return from get_regs
+ *
+ * Put the correct FP bits in, they might be wrong as a result
+ * of our lazy FP restore.
+ */
+
+#define PT_MUNGE_MSR(msr, task) ({ (msr) | (task)->thread.fpexc_mode; })
+
+static inline int ptrace_set_debugreg(struct task_struct *task,
+                                      unsigned long addr, unsigned long data)
+{
+        /* We only support one DABR and no IABRS at the moment */
+        if (addr > 0)
+                return -EINVAL;
+
+        /* The bottom 3 bits are flags */
+        if ((data & ~0x7UL) >= TASK_SIZE)
+                return -EIO;
+
+        /* Ensure translation is on */
+        if (data && !(data & DABR_TRANSLATION))
+                return -EIO;
+
+        task->thread.dabr = data;
+        return 0;
+}
+
+#endif /* _POWERPC_PTRACE_PPC64_H */
diff --git a/arch/powerpc/kernel/ptrace.c b/arch/powerpc/kernel/ptrace.c
index 36db6f5cb54c..da53b0d4114b 100644
--- a/arch/powerpc/kernel/ptrace.c
+++ b/arch/powerpc/kernel/ptrace.c
@@ -36,208 +36,18 @@
 #include <asm/system.h>
 
 #ifdef CONFIG_PPC64
-#include "ptrace-common.h"
-#endif
-
-#ifdef CONFIG_PPC32
-/*
- * Set of msr bits that gdb can change on behalf of a process.
- */
-#if defined(CONFIG_40x) || defined(CONFIG_BOOKE)
-#define MSR_DEBUGCHANGE 0
+#include "ptrace-ppc64.h"
 #else
-#define MSR_DEBUGCHANGE (MSR_SE | MSR_BE)
+#include "ptrace-ppc32.h"
 #endif
-#endif /* CONFIG_PPC32 */
+
+#include "ptrace-common.h"
 
 /*
  * does not yet catch signals sent when the child dies.
  * in exit.c or in signal.c.
  */
 
-#ifdef CONFIG_PPC32
-/*
- * Get contents of register REGNO in task TASK.
- */
-static inline unsigned long get_reg(struct task_struct *task, int regno)
-{
-        if (regno < sizeof(struct pt_regs) / sizeof(unsigned long)
-            && task->thread.regs != NULL)
-                return ((unsigned long *)task->thread.regs)[regno];
-        return (0);
-}
-
-/*
- * Write contents of register REGNO in task TASK.
- */
-static inline int put_reg(struct task_struct *task, int regno,
-                          unsigned long data)
-{
-        if (regno <= PT_MQ && task->thread.regs != NULL) {
-                if (regno == PT_MSR)
-                        data = (data & MSR_DEBUGCHANGE)
-                                | (task->thread.regs->msr & ~MSR_DEBUGCHANGE);
-                ((unsigned long *)task->thread.regs)[regno] = data;
-                return 0;
-        }
-        return -EIO;
-}
-
-#ifdef CONFIG_ALTIVEC
-/*
- * Get contents of AltiVec register state in task TASK
- */
-static inline int get_vrregs(unsigned long __user *data, struct task_struct *task)
-{
-        int i, j;
-
-        if (!access_ok(VERIFY_WRITE, data, 133 * sizeof(unsigned long)))
-                return -EFAULT;
-
-        /* copy AltiVec registers VR[0] .. VR[31] */
-        for (i = 0; i < 32; i++)
-                for (j = 0; j < 4; j++, data++)
-                        if (__put_user(task->thread.vr[i].u[j], data))
-                                return -EFAULT;
-
-        /* copy VSCR */
-        for (i = 0; i < 4; i++, data++)
-                if (__put_user(task->thread.vscr.u[i], data))
-                        return -EFAULT;
-
-        /* copy VRSAVE */
-        if (__put_user(task->thread.vrsave, data))
-                return -EFAULT;
-
-        return 0;
-}
-
-/*
- * Write contents of AltiVec register state into task TASK.
- */
-static inline int set_vrregs(struct task_struct *task, unsigned long __user *data)
-{
-        int i, j;
-
-        if (!access_ok(VERIFY_READ, data, 133 * sizeof(unsigned long)))
-                return -EFAULT;
-
-        /* copy AltiVec registers VR[0] .. VR[31] */
-        for (i = 0; i < 32; i++)
-                for (j = 0; j < 4; j++, data++)
-                        if (__get_user(task->thread.vr[i].u[j], data))
-                                return -EFAULT;
-
-        /* copy VSCR */
-        for (i = 0; i < 4; i++, data++)
-                if (__get_user(task->thread.vscr.u[i], data))
-                        return -EFAULT;
-
-        /* copy VRSAVE */
-        if (__get_user(task->thread.vrsave, data))
-                return -EFAULT;
-
-        return 0;
-}
-#endif
-
-#ifdef CONFIG_SPE
-
-/*
- * For get_evrregs/set_evrregs functions 'data' has the following layout:
- *
- * struct {
- *   u32 evr[32];
- *   u64 acc;
- *   u32 spefscr;
- * }
- */
-
-/*
- * Get contents of SPE register state in task TASK.
- */
-static inline int get_evrregs(unsigned long *data, struct task_struct *task)
-{
-        int i;
-
-        if (!access_ok(VERIFY_WRITE, data, 35 * sizeof(unsigned long)))
-                return -EFAULT;
-
-        /* copy SPEFSCR */
-        if (__put_user(task->thread.spefscr, &data[34]))
-                return -EFAULT;
-
-        /* copy SPE registers EVR[0] .. EVR[31] */
-        for (i = 0; i < 32; i++, data++)
-                if (__put_user(task->thread.evr[i], data))
-                        return -EFAULT;
-
-        /* copy ACC */
-        if (__put_user64(task->thread.acc, (unsigned long long *)data))
-                return -EFAULT;
-
-        return 0;
-}
-
-/*
- * Write contents of SPE register state into task TASK.
- */
-static inline int set_evrregs(struct task_struct *task, unsigned long *data)
-{
-        int i;
-
-        if (!access_ok(VERIFY_READ, data, 35 * sizeof(unsigned long)))
-                return -EFAULT;
-
-        /* copy SPEFSCR */
-        if (__get_user(task->thread.spefscr, &data[34]))
-                return -EFAULT;
-
-        /* copy SPE registers EVR[0] .. EVR[31] */
-        for (i = 0; i < 32; i++, data++)
-                if (__get_user(task->thread.evr[i], data))
-                        return -EFAULT;
-        /* copy ACC */
-        if (__get_user64(task->thread.acc, (unsigned long long*)data))
-                return -EFAULT;
-
-        return 0;
-}
-#endif /* CONFIG_SPE */
-
-static inline void
-set_single_step(struct task_struct *task)
-{
-        struct pt_regs *regs = task->thread.regs;
-
-        if (regs != NULL) {
-#if defined(CONFIG_40x) || defined(CONFIG_BOOKE)
-                task->thread.dbcr0 = DBCR0_IDM | DBCR0_IC;
-                regs->msr |= MSR_DE;
-#else
-                regs->msr |= MSR_SE;
-#endif
-        }
-        set_tsk_thread_flag(task, TIF_SINGLESTEP);
-}
-
-static inline void
-clear_single_step(struct task_struct *task)
-{
-        struct pt_regs *regs = task->thread.regs;
-
-        if (regs != NULL) {
-#if defined(CONFIG_40x) || defined(CONFIG_BOOKE)
-                task->thread.dbcr0 = 0;
-                regs->msr &= ~MSR_DE;
-#else
-                regs->msr &= ~MSR_SE;
-#endif
-        }
-        clear_tsk_thread_flag(task, TIF_SINGLESTEP);
-}
-#endif /* CONFIG_PPC32 */
-
 /*
  * Called by kernel/ptrace.c when detaching..
  *
diff --git a/arch/powerpc/kernel/ptrace32.c b/arch/powerpc/kernel/ptrace32.c
index 9b9a230349bc..1bf1f450e1ab 100644
--- a/arch/powerpc/kernel/ptrace32.c
+++ b/arch/powerpc/kernel/ptrace32.c
@@ -33,6 +33,7 @@
 #include <asm/pgtable.h>
 #include <asm/system.h>
 
+#include "ptrace-ppc64.h"
 #include "ptrace-common.h"
 
 /*