linux_dsm_epyc7002/arch/powerpc/include/asm/kprobes.h
Naveen N. Rao 6cc89bad60 powerpc/kprobes: Invoke handlers directly
Invoke the kprobe handlers directly rather than through notify_die(), to
reduce path taken for handling kprobes. Similar to commit 6f6343f53d
("kprobes/x86: Call exception handlers directly from do_int3/do_debug").

While at it, rename post_kprobe_handler() to kprobe_post_handler() for
more uniform naming.

Reported-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-11-23 22:56:25 +11:00

139 lines
4.3 KiB
C

#ifndef _ASM_POWERPC_KPROBES_H
#define _ASM_POWERPC_KPROBES_H
#ifdef __KERNEL__
/*
* Kernel Probes (KProbes)
*
* 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
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* 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-Nov Modified for PPC64 by Ananth N Mavinakayanahalli
* <ananth@in.ibm.com>
*/
#include <linux/types.h>
#include <linux/ptrace.h>
#include <linux/percpu.h>
#include <asm/probes.h>
#include <asm/code-patching.h>
#ifdef CONFIG_KPROBES
#define __ARCH_WANT_KPROBES_INSN_SLOT
struct pt_regs;
struct kprobe;
typedef ppc_opcode_t kprobe_opcode_t;
#define MAX_INSN_SIZE 1
#ifdef PPC64_ELF_ABI_v2
/* PPC64 ABIv2 needs local entry point */
#define kprobe_lookup_name(name, addr) \
{ \
addr = (kprobe_opcode_t *)kallsyms_lookup_name(name); \
if (addr) \
addr = (kprobe_opcode_t *)ppc_function_entry(addr); \
}
#elif defined(PPC64_ELF_ABI_v1)
/*
* 64bit powerpc ABIv1 uses function descriptors:
* - Check for the dot variant of the symbol first.
* - If that fails, try looking up the symbol provided.
*
* This ensures we always get to the actual symbol and not the descriptor.
* Also handle <module:symbol> format.
*/
#define kprobe_lookup_name(name, addr) \
{ \
char dot_name[MODULE_NAME_LEN + 1 + KSYM_NAME_LEN]; \
char *modsym; \
bool dot_appended = false; \
if ((modsym = strchr(name, ':')) != NULL) { \
modsym++; \
if (*modsym != '\0' && *modsym != '.') { \
/* Convert to <module:.symbol> */ \
strncpy(dot_name, name, modsym - name); \
dot_name[modsym - name] = '.'; \
dot_name[modsym - name + 1] = '\0'; \
strncat(dot_name, modsym, \
sizeof(dot_name) - (modsym - name) - 2);\
dot_appended = true; \
} else { \
dot_name[0] = '\0'; \
strncat(dot_name, name, sizeof(dot_name) - 1); \
} \
} else if (name[0] != '.') { \
dot_name[0] = '.'; \
dot_name[1] = '\0'; \
strncat(dot_name, name, KSYM_NAME_LEN - 2); \
dot_appended = true; \
} else { \
dot_name[0] = '\0'; \
strncat(dot_name, name, KSYM_NAME_LEN - 1); \
} \
addr = (kprobe_opcode_t *)kallsyms_lookup_name(dot_name); \
if (!addr && dot_appended) { \
/* Let's try the original non-dot symbol lookup */ \
addr = (kprobe_opcode_t *)kallsyms_lookup_name(name); \
} \
}
#endif
#define flush_insn_slot(p) do { } while (0)
#define kretprobe_blacklist_size 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;
};
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);
extern int kprobe_handler(struct pt_regs *regs);
extern int kprobe_post_handler(struct pt_regs *regs);
#else
static inline int kprobe_handler(struct pt_regs *regs) { return 0; }
static inline int kprobe_post_handler(struct pt_regs *regs) { return 0; }
#endif /* CONFIG_KPROBES */
#endif /* __KERNEL__ */
#endif /* _ASM_POWERPC_KPROBES_H */