x86: prepare kprobes code for x86 unification

This patch cleanup kprobes code on x86 for unification.
This patch is based on Arjan's previous work.

- Remove spurious whitespace changes
- Add harmless includes
- Make the 32/64 files more identical
 - Generalize structure fields' and local variable name.
 - Wrap accessing to stack address by macros.
 - Modify bitmap making macro.
 - Merge fixup code into is_riprel() and change its name to fix_riprel().
 - Set MAX_INSN_SIZE to 16 on both arch.
 - Use u32 for bitmaps on both architectures.
 - Clarify some comments.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Jim Keniston <jkenisto@us.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

arch/x86/mm/fault_32.c

@@ -25,7 +25,6 @@
 #include <linux/kprobes.h>
 #include <linux/uaccess.h>
 #include <linux/kdebug.h>
-#include <linux/kprobes.h>
 
 #include <asm/system.h>
 #include <asm/desc.h>

arch/x86/mm/fault_64.c

@@ -25,7 +25,6 @@
 #include <linux/kprobes.h>
 #include <linux/uaccess.h>
 #include <linux/kdebug.h>
-#include <linux/kprobes.h>
 
 #include <asm/system.h>
 #include <asm/pgalloc.h>

include/asm-x86/kprobes_32.h

@@ -2,7 +2,6 @@
 #define _ASM_KPROBES_H
 /*
  *  Kernel Probes (KProbes)
- *  include/asm-i386/kprobes.h
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -23,14 +22,17 @@
  * 2002-Oct	Created by Vamsi Krishna S <vamsi_krishna@in.ibm.com> Kernel
  *		Probes initial implementation ( includes suggestions from
  *		Rusty Russell).
+ * 2004-Oct	Prasanna S Panchamukhi <prasanna@in.ibm.com> and Jim Keniston
+ *		kenistoj@us.ibm.com adopted from i386.
  */
 #include <linux/types.h>
 #include <linux/ptrace.h>
+#include <linux/percpu.h>
 
 #define  __ARCH_WANT_KPROBES_INSN_SLOT
 
-struct kprobe;
 struct pt_regs;
+struct kprobe;
 
 typedef u8 kprobe_opcode_t;
 #define BREAKPOINT_INSTRUCTION	0xcc
@@ -38,9 +40,11 @@ typedef u8 kprobe_opcode_t;
 #define MAX_INSN_SIZE 16
 #define MAX_STACK_SIZE 64
 #define MIN_STACK_SIZE(ADDR) (((MAX_STACK_SIZE) < \
-	(((unsigned long)current_thread_info()) + THREAD_SIZE - (ADDR))) \
+	(((unsigned long)current_thread_info()) + THREAD_SIZE \
+	 - (unsigned long)(ADDR))) \
 	? (MAX_STACK_SIZE) \
-	: (((unsigned long)current_thread_info()) + THREAD_SIZE - (ADDR)))
+	: (((unsigned long)current_thread_info()) + THREAD_SIZE \
+	   - (unsigned long)(ADDR)))
 
 #define ARCH_SUPPORTS_KRETPROBES
 #define flush_insn_slot(p)	do { } while (0)
@@ -55,8 +59,12 @@ struct arch_specific_insn {
 	/* copy of the original instruction */
 	kprobe_opcode_t *insn;
 	/*
-	 * If this flag is not 0, this kprobe can be boost when its
-	 * post_handler and break_handler is not set.
+	 * boostable = -1: This instruction type is not boostable.
+	 * boostable = 0: This instruction type is boostable.
+	 * boostable = 1: This instruction has been boosted: we have
+	 * added a relative jump after the instruction copy in insn,
+	 * so no single-step and fixup are needed (unless there's
+	 * a post_handler or break_handler).
 	 */
 	int boostable;
 };
@@ -64,16 +72,16 @@ struct arch_specific_insn {
 struct prev_kprobe {
 	struct kprobe *kp;
 	unsigned long status;
-	unsigned long old_eflags;
-	unsigned long saved_eflags;
+	unsigned long old_flags;
+	unsigned long saved_flags;
 };
 
 /* per-cpu kprobe control block */
 struct kprobe_ctlblk {
 	unsigned long kprobe_status;
-	unsigned long kprobe_old_eflags;
-	unsigned long kprobe_saved_eflags;
-	unsigned long *jprobe_saved_esp;
+	unsigned long kprobe_old_flags;
+	unsigned long kprobe_saved_flags;
+	unsigned long *jprobe_saved_sp;
 	struct pt_regs jprobe_saved_regs;
 	kprobe_opcode_t jprobes_stack[MAX_STACK_SIZE];
 	struct prev_kprobe prev_kprobe;
@@ -88,7 +96,7 @@ static inline void restore_interrupts(struct pt_regs *regs)
 		local_irq_enable();
 }
 
+extern int kprobe_fault_handler(struct pt_regs *regs, int trapnr);
 extern int kprobe_exceptions_notify(struct notifier_block *self,
 				    unsigned long val, void *data);
-extern int kprobe_fault_handler(struct pt_regs *regs, int trapnr);
 #endif				/* _ASM_KPROBES_H */

include/asm-x86/kprobes_64.h

@@ -2,7 +2,6 @@
 #define _ASM_KPROBES_H
 /*
  *  Kernel Probes (KProbes)
- *  include/asm-x86_64/kprobes.h
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -20,6 +19,9 @@
  *
  * Copyright (C) IBM Corporation, 2002, 2004
  *
+ * 2002-Oct	Created by Vamsi Krishna S <vamsi_krishna@in.ibm.com> Kernel
+ *		Probes initial implementation ( includes suggestions from
+ *		Rusty Russell).
  * 2004-Oct	Prasanna S Panchamukhi <prasanna@in.ibm.com> and Jim Keniston
  *		kenistoj@us.ibm.com adopted from i386.
  */
@@ -35,19 +37,22 @@ struct kprobe;
 typedef u8 kprobe_opcode_t;
 #define BREAKPOINT_INSTRUCTION	0xcc
 #define RELATIVEJUMP_INSTRUCTION 0xe9
-#define MAX_INSN_SIZE 15
+#define MAX_INSN_SIZE 16
 #define MAX_STACK_SIZE 64
 #define MIN_STACK_SIZE(ADDR) (((MAX_STACK_SIZE) < \
-	(((unsigned long)current_thread_info()) + THREAD_SIZE - (ADDR))) \
+	(((unsigned long)current_thread_info()) + THREAD_SIZE \
+	 - (unsigned long)(ADDR))) \
 	? (MAX_STACK_SIZE) \
-	: (((unsigned long)current_thread_info()) + THREAD_SIZE - (ADDR)))
+	: (((unsigned long)current_thread_info()) + THREAD_SIZE \
+	   - (unsigned long)(ADDR)))
 
 #define ARCH_SUPPORTS_KRETPROBES
+#define flush_insn_slot(p)	do { } while (0)
+
 extern const int kretprobe_blacklist_size;
 
+void arch_remove_kprobe(struct kprobe *p);
 void kretprobe_trampoline(void);
-extern void arch_remove_kprobe(struct kprobe *p);
-#define flush_insn_slot(p)	do { } while (0)
 
 /* Architecture specific copy of original instruction*/
 struct arch_specific_insn {
@@ -67,16 +72,16 @@ struct arch_specific_insn {
 struct prev_kprobe {
 	struct kprobe *kp;
 	unsigned long status;
-	unsigned long old_rflags;
-	unsigned long saved_rflags;
+	unsigned long old_flags;
+	unsigned long saved_flags;
 };
 
 /* per-cpu kprobe control block */
 struct kprobe_ctlblk {
 	unsigned long kprobe_status;
-	unsigned long kprobe_old_rflags;
-	unsigned long kprobe_saved_rflags;
-	unsigned long *jprobe_saved_rsp;
+	unsigned long kprobe_old_flags;
+	unsigned long kprobe_saved_flags;
+	unsigned long *jprobe_saved_sp;
 	struct pt_regs jprobe_saved_regs;
 	kprobe_opcode_t jprobes_stack[MAX_STACK_SIZE];
 	struct prev_kprobe prev_kprobe;
@@ -91,10 +96,7 @@ static inline void restore_interrupts(struct pt_regs *regs)
 		local_irq_enable();
 }
 
-extern int post_kprobe_handler(struct pt_regs *regs);
 extern int kprobe_fault_handler(struct pt_regs *regs, int trapnr);
-extern int kprobe_handler(struct pt_regs *regs);
-
 extern int kprobe_exceptions_notify(struct notifier_block *self,
 				    unsigned long val, void *data);
 #endif				/* _ASM_KPROBES_H */