MIPS: kprobe: Add support.
This patch is based on previous work by Sony and Himanshu Chauhan.
I have done some cleanup and implemented JProbes and KRETPROBES. The
KRETPROBES part is pretty much copied verbatim from powerpc. A possible
future enhance might be to factor out the common code.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Cc: Himanshu Chauhan <hschauhan@nulltrace.org>
To: linux-mips@linux-mips.org
To: ananth@in.ibm.com,
To: anil.s.keshavamurthy@intel.com
To: davem@davemloft.net
To: masami.hiramatsu.pt@hitachi.com
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/1525/
Patchwork: https://patchwork.linux-mips.org/patch/1530/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/include/asm/break.h b/arch/mips/include/asm/break.h
index 44437ed..9161e68 100644
--- a/arch/mips/include/asm/break.h
+++ b/arch/mips/include/asm/break.h
@@ -30,6 +30,8 @@
#define BRK_BUG 512 /* Used by BUG() */
#define BRK_KDB 513 /* Used in KDB_ENTER() */
#define BRK_MEMU 514 /* Used by FPU emulator */
+#define BRK_KPROBE_BP 515 /* Kprobe break */
+#define BRK_KPROBE_SSTEPBP 516 /* Kprobe single step software implementation */
#define BRK_MULOVF 1023 /* Multiply overflow */
#endif /* __ASM_BREAK_H */
diff --git a/arch/mips/include/asm/kdebug.h b/arch/mips/include/asm/kdebug.h
index 5bf62aa..6a9af5f 100644
--- a/arch/mips/include/asm/kdebug.h
+++ b/arch/mips/include/asm/kdebug.h
@@ -8,6 +8,9 @@
DIE_FP,
DIE_TRAP,
DIE_RI,
+ DIE_PAGE_FAULT,
+ DIE_BREAK,
+ DIE_SSTEPBP
};
#endif /* _ASM_MIPS_KDEBUG_H */
diff --git a/arch/mips/include/asm/kprobes.h b/arch/mips/include/asm/kprobes.h
new file mode 100644
index 0000000..e6ea4d4
--- /dev/null
+++ b/arch/mips/include/asm/kprobes.h
@@ -0,0 +1,92 @@
+/*
+ * Kernel Probes (KProbes)
+ * include/asm-mips/kprobes.h
+ *
+ * Copyright 2006 Sony Corp.
+ * Copyright 2010 Cavium Networks
+ *
+ * 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; version 2 of the License.
+ *
+ * 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
+ */
+
+#ifndef _ASM_KPROBES_H
+#define _ASM_KPROBES_H
+
+#include <linux/ptrace.h>
+#include <linux/types.h>
+
+#include <asm/cacheflush.h>
+#include <asm/kdebug.h>
+#include <asm/inst.h>
+
+#define __ARCH_WANT_KPROBES_INSN_SLOT
+
+struct kprobe;
+struct pt_regs;
+
+typedef union mips_instruction kprobe_opcode_t;
+
+#define MAX_INSN_SIZE 2
+
+#define flush_insn_slot(p) \
+do { \
+ flush_icache_range((unsigned long)p->addr, \
+ (unsigned long)p->addr + \
+ (MAX_INSN_SIZE * sizeof(kprobe_opcode_t))); \
+} while (0)
+
+
+#define kretprobe_blacklist_size 0
+
+void arch_remove_kprobe(struct kprobe *p);
+
+/* Architecture specific copy of original instruction*/
+struct arch_specific_insn {
+ /* copy of the original instruction */
+ kprobe_opcode_t *insn;
+};
+
+struct prev_kprobe {
+ struct kprobe *kp;
+ unsigned long status;
+ unsigned long old_SR;
+ unsigned long saved_SR;
+ unsigned long saved_epc;
+};
+
+#define MAX_JPROBES_STACK_SIZE 128
+#define MAX_JPROBES_STACK_ADDR \
+ (((unsigned long)current_thread_info()) + THREAD_SIZE - 32 - sizeof(struct pt_regs))
+
+#define MIN_JPROBES_STACK_SIZE(ADDR) \
+ ((((ADDR) + MAX_JPROBES_STACK_SIZE) > MAX_JPROBES_STACK_ADDR) \
+ ? MAX_JPROBES_STACK_ADDR - (ADDR) \
+ : MAX_JPROBES_STACK_SIZE)
+
+
+/* per-cpu kprobe control block */
+struct kprobe_ctlblk {
+ unsigned long kprobe_status;
+ unsigned long kprobe_old_SR;
+ unsigned long kprobe_saved_SR;
+ unsigned long kprobe_saved_epc;
+ unsigned long jprobe_saved_sp;
+ struct pt_regs jprobe_saved_regs;
+ u8 jprobes_stack[MAX_JPROBES_STACK_SIZE];
+ struct prev_kprobe prev_kprobe;
+};
+
+extern int kprobe_exceptions_notify(struct notifier_block *self,
+ unsigned long val, void *data);
+
+#endif /* _ASM_KPROBES_H */