[POWERPC] kprobes: Eliminate sstep exception if instruction can be emulated

[safe/jmp/linux-2.6] / include / asm-powerpc / kprobes.h

diff --git a/include/asm-powerpc/kprobes.h b/include/asm-powerpc/kprobes.h
index d9129d2..f850ca7 100644 (file)
--- a/include/asm-powerpc/kprobes.h
+++ b/include/asm-powerpc/kprobes.h
@@ -1,8 +1,8 @@
-#ifndef _ASM_KPROBES_H
-#define _ASM_KPROBES_H
+#ifndef _ASM_POWERPC_KPROBES_H
+#define _ASM_POWERPC_KPROBES_H
+#ifdef __KERNEL__
 /*
  *  Kernel Probes (KProbes)
- *  include/asm-ppc64/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
@@ -28,8 +28,12 @@
  */
 #include <linux/types.h>
 #include <linux/ptrace.h>
+#include <linux/percpu.h>
+
+#define  __ARCH_WANT_KPROBES_INSN_SLOT
 
 struct pt_regs;
+struct kprobe;
 
 typedef unsigned int kprobe_opcode_t;
 #define BREAKPOINT_INSTRUCTION 0x7fe00008      /* trap */
@@ -40,28 +44,71 @@ typedef unsigned int kprobe_opcode_t;
 #define IS_TDI(instr)          (((instr) & 0xfc000000) == 0x08000000)
 #define IS_TWI(instr)          (((instr) & 0xfc000000) == 0x0c000000)
 
-#define JPROBE_ENTRY(pentry)   (kprobe_opcode_t *)((func_descr_t *)pentry)
+#ifdef CONFIG_PPC64
+/*
+ * 64bit powerpc uses function descriptors.
+ * Handle cases where:
+ *             - User passes a <.symbol> or <module:.symbol>
+ *             - User passes a <symbol> or <module:symbol>
+ *             - User passes a non-existant symbol, kallsyms_lookup_name
+ *               returns 0. Don't deref the NULL pointer in that case
+ */
+#define kprobe_lookup_name(name, addr)                                 \
+{                                                                      \
+       addr = (kprobe_opcode_t *)kallsyms_lookup_name(name);           \
+       if (addr) {                                                     \
+               char *colon;                                            \
+               if ((colon = strchr(name, ':')) != NULL) {              \
+                       colon++;                                        \
+                       if (*colon != '\0' && *colon != '.')            \
+                               addr = *(kprobe_opcode_t **)addr;       \
+               } else if (name[0] != '.')                              \
+                       addr = *(kprobe_opcode_t **)addr;               \
+       }                                                               \
+}
 
+#define JPROBE_ENTRY(pentry)   (kprobe_opcode_t *)((func_descr_t *)pentry)
 #define is_trap(instr) (IS_TW(instr) || IS_TD(instr) || \
                        IS_TWI(instr) || IS_TDI(instr))
+#else
+/* Use stock kprobe_lookup_name since ppc32 doesn't use function descriptors */
+#define JPROBE_ENTRY(pentry)   (kprobe_opcode_t *)(pentry)
+#define is_trap(instr) (IS_TW(instr) || IS_TWI(instr))
+#endif
 
 #define ARCH_SUPPORTS_KRETPROBES
+#define  ARCH_INACTIVE_KPROBE_COUNT 1
+#define flush_insn_slot(p)     do { } while (0)
+
 void kretprobe_trampoline(void);
+extern void arch_remove_kprobe(struct kprobe *p);
 
 /* Architecture specific copy of original instruction */
 struct arch_specific_insn {
        /* copy of original instruction */
        kprobe_opcode_t *insn;
+       /*
+        * Set in kprobes code, initially to 0. If the instruction can be
+        * eumulated, this is set to 1, if not, to -1.
+        */
+       int boostable;
+};
+
+struct prev_kprobe {
+       struct kprobe *kp;
+       unsigned long status;
+       unsigned long saved_msr;
+};
+
+/* per-cpu kprobe control block */
+struct kprobe_ctlblk {
+       unsigned long kprobe_status;
+       unsigned long kprobe_saved_msr;
+       struct pt_regs jprobe_saved_regs;
+       struct prev_kprobe prev_kprobe;
 };
 
-#ifdef CONFIG_KPROBES
 extern int kprobe_exceptions_notify(struct notifier_block *self,
-                                   unsigned long val, void *data);
-#else                          /* !CONFIG_KPROBES */
-static inline int kprobe_exceptions_notify(struct notifier_block *self,
-                                          unsigned long val, void *data)
-{
-       return 0;
-}
-#endif
-#endif                         /* _ASM_KPROBES_H */
+                                       unsigned long val, void *data);
+#endif /* __KERNEL__ */
+#endif /* _ASM_POWERPC_KPROBES_H */