LXR linux/arch/powerpc/include/asm/kprobes.h

   1#ifndef _ASM_POWERPC_KPROBES_H
   2#define _ASM_POWERPC_KPROBES_H
   3#ifdef __KERNEL__
   4/*
   5 *  Kernel Probes (KProbes)
   6 *
   7 * This program is free software; you can redistribute it and/or modify
   8 * it under the terms of the GNU General Public License as published by
   9 * the Free Software Foundation; either version 2 of the License, or
  10 * (at your option) any later version.
  11 *
  12 * This program is distributed in the hope that it will be useful,
  13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 * GNU General Public License for more details.
  16 *
  17 * You should have received a copy of the GNU General Public License
  18 * along with this program; if not, write to the Free Software
  19 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  20 *
  21 * Copyright (C) IBM Corporation, 2002, 2004
  22 *
  23 * 2002-Oct     Created by Vamsi Krishna S <vamsi_krishna@in.ibm.com> Kernel
  24 *              Probes initial implementation ( includes suggestions from
  25 *              Rusty Russell).
  26 * 2004-Nov     Modified for PPC64 by Ananth N Mavinakayanahalli
  27 *              <ananth@in.ibm.com>
  28 */
  29#include <linux/types.h>
  30#include <linux/ptrace.h>
  31#include <linux/percpu.h>
  32#include <asm/probes.h>
  33#include <asm/code-patching.h>
  34
  35#define  __ARCH_WANT_KPROBES_INSN_SLOT
  36
  37struct pt_regs;
  38struct kprobe;
  39
  40typedef ppc_opcode_t kprobe_opcode_t;
  41#define MAX_INSN_SIZE 1
  42
  43#ifdef PPC64_ELF_ABI_v2
  44/* PPC64 ABIv2 needs local entry point */
  45#define kprobe_lookup_name(name, addr)                                  \
  46{                                                                       \
  47        addr = (kprobe_opcode_t *)kallsyms_lookup_name(name);           \
  48        if (addr)                                                       \
  49                addr = (kprobe_opcode_t *)ppc_function_entry(addr);     \
  50}
  51#elif defined(PPC64_ELF_ABI_v1)
  52/*
  53 * 64bit powerpc ABIv1 uses function descriptors:
  54 * - Check for the dot variant of the symbol first.
  55 * - If that fails, try looking up the symbol provided.
  56 *
  57 * This ensures we always get to the actual symbol and not the descriptor.
  58 * Also handle <module:symbol> format.
  59 */
  60#define kprobe_lookup_name(name, addr)                                  \
  61{                                                                       \
  62        char dot_name[MODULE_NAME_LEN + 1 + KSYM_NAME_LEN];             \
  63        char *modsym;                                                   \
  64        bool dot_appended = false;                                      \
  65        if ((modsym = strchr(name, ':')) != NULL) {                     \
  66                modsym++;                                               \
  67                if (*modsym != '\0' && *modsym != '.') {                \
  68                        /* Convert to <module:.symbol> */               \
  69                        strncpy(dot_name, name, modsym - name);         \
  70                        dot_name[modsym - name] = '.';                  \
  71                        dot_name[modsym - name + 1] = '\0';             \
  72                        strncat(dot_name, modsym,                       \
  73                                sizeof(dot_name) - (modsym - name) - 2);\
  74                        dot_appended = true;                            \
  75                } else {                                                \
  76                        dot_name[0] = '\0';                             \
  77                        strncat(dot_name, name, sizeof(dot_name) - 1);  \
  78                }                                                       \
  79        } else if (name[0] != '.') {                                    \
  80                dot_name[0] = '.';                                      \
  81                dot_name[1] = '\0';                                     \
  82                strncat(dot_name, name, KSYM_NAME_LEN - 2);             \
  83                dot_appended = true;                                    \
  84        } else {                                                        \
  85                dot_name[0] = '\0';                                     \
  86                strncat(dot_name, name, KSYM_NAME_LEN - 1);             \
  87        }                                                               \
  88        addr = (kprobe_opcode_t *)kallsyms_lookup_name(dot_name);       \
  89        if (!addr && dot_appended) {                                    \
  90                /* Let's try the original non-dot symbol lookup */      \
  91                addr = (kprobe_opcode_t *)kallsyms_lookup_name(name);   \
  92        }                                                               \
  93}
  94#endif
  95
  96#define flush_insn_slot(p)      do { } while (0)
  97#define kretprobe_blacklist_size 0
  98
  99void kretprobe_trampoline(void);
 100extern void arch_remove_kprobe(struct kprobe *p);
 101
 102/* Architecture specific copy of original instruction */
 103struct arch_specific_insn {
 104        /* copy of original instruction */
 105        kprobe_opcode_t *insn;
 106        /*
 107         * Set in kprobes code, initially to 0. If the instruction can be
 108         * eumulated, this is set to 1, if not, to -1.
 109         */
 110        int boostable;
 111};
 112
 113struct prev_kprobe {
 114        struct kprobe *kp;
 115        unsigned long status;
 116        unsigned long saved_msr;
 117};
 118
 119/* per-cpu kprobe control block */
 120struct kprobe_ctlblk {
 121        unsigned long kprobe_status;
 122        unsigned long kprobe_saved_msr;
 123        struct pt_regs jprobe_saved_regs;
 124        struct prev_kprobe prev_kprobe;
 125};
 126
 127extern int kprobe_exceptions_notify(struct notifier_block *self,
 128                                        unsigned long val, void *data);
 129extern int kprobe_fault_handler(struct pt_regs *regs, int trapnr);
 130#endif /* __KERNEL__ */
 131#endif  /* _ASM_POWERPC_KPROBES_H */
 132