MIPS: Declare mips_debugfs_dir in a header

We have many extern declarations of mips_debugfs_dir through arch/mips/
in various C files. Unify them by declaring mips_debugfs_dir in a
header, including it in each affected C file & removing the duplicate
declarations.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-kernel@vger.kernel.org
Cc: Joe Perches <joe@perches.com>
Cc: Jaedon Shin <jaedon.shin@gmail.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: David Daney <david.daney@cavium.com>
Cc: Zubair Lutfullah Kakakhel <Zubair.Kakakhel@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: James Cowgill <James.Cowgill@imgtec.com>
Patchwork: https://patchwork.linux-mips.org/patch/11181/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/include/asm/debug.h

+/*
+ * Copyright (C) 2015 Imagination Technologies
+ *
+ * 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.
+ */
+
+#ifndef __MIPS_ASM_DEBUG_H__
+#define __MIPS_ASM_DEBUG_H__
+
+#include <linux/dcache.h>
+
+/*
+ * mips_debugfs_dir corresponds to the "mips" directory at the top level
+ * of the DebugFS hierarchy. MIPS-specific DebugFS entires should be
+ * placed beneath this directory.
+ */
+extern struct dentry *mips_debugfs_dir;
+
+#endif /* __MIPS_ASM_DEBUG_H__ */

arch/mips/kernel/mips-r2-to-r6-emul.c

@@ -22,6 +22,7 @@
 #include <asm/asm.h>
 #include <asm/branch.h>
 #include <asm/break.h>
+#include <asm/debug.h>
 #include <asm/fpu.h>
 #include <asm/fpu_emulator.h>
 #include <asm/inst.h>
@@ -2363,7 +2364,6 @@ static const struct file_operations mipsr2_clear_fops = {
 
 static int __init mipsr2_init_debugfs(void)
 {
-	extern struct dentry	*mips_debugfs_dir;
 	struct dentry		*mipsr2_emul;
 
 	if (!mips_debugfs_dir)

arch/mips/kernel/segment.c

@@ -10,6 +10,7 @@
 #include <linux/debugfs.h>
 #include <linux/seq_file.h>
 #include <asm/cpu.h>
+#include <asm/debug.h>
 #include <asm/mipsregs.h>
 
 static void build_segment_config(char *str, unsigned int cfg)
@@ -91,7 +92,6 @@ static const struct file_operations segments_fops = {
 
 static int __init segments_info(void)
 {
-	extern struct dentry *mips_debugfs_dir;
 	struct dentry *segments;
 
 	if (cpu_has_segments) {

arch/mips/kernel/setup.c

@@ -33,6 +33,7 @@
 #include <asm/cache.h>
 #include <asm/cdmm.h>
 #include <asm/cpu.h>
+#include <asm/debug.h>
 #include <asm/sections.h>
 #include <asm/setup.h>
 #include <asm/smp-ops.h>

arch/mips/kernel/spinlock_test.c

@@ -5,7 +5,7 @@
 #include <linux/debugfs.h>
 #include <linux/export.h>
 #include <linux/spinlock.h>
-
+#include <asm/debug.h>
 
 static int ss_get(void *data, u64 *val)
 {
@@ -115,8 +115,6 @@ static int multi_get(void *data, u64 *val)
 
 DEFINE_SIMPLE_ATTRIBUTE(fops_multi, multi_get, NULL, "%llu\n");
 
-
-extern struct dentry *mips_debugfs_dir;
 static int __init spinlock_test(void)
 {
 	struct dentry *d;

arch/mips/kernel/unaligned.c

@@ -85,6 +85,7 @@
 #include <asm/branch.h>
 #include <asm/byteorder.h>
 #include <asm/cop2.h>
+#include <asm/debug.h>
 #include <asm/fpu.h>
 #include <asm/fpu_emulator.h>
 #include <asm/inst.h>
@@ -2295,7 +2296,6 @@ asmlinkage void do_ade(struct pt_regs *regs)
 }
 
 #ifdef CONFIG_DEBUG_FS
-extern struct dentry *mips_debugfs_dir;
 static int __init debugfs_unaligned(void)
 {
 	struct dentry *d;

arch/mips/math-emu/me-debugfs.c

@@ -4,6 +4,7 @@
 #include <linux/init.h>
 #include <linux/percpu.h>
 #include <linux/types.h>
+#include <asm/debug.h>
 #include <asm/fpu_emulator.h>
 #include <asm/local.h>
 
@@ -27,7 +28,6 @@ static int fpuemu_stat_get(void *data, u64 *val)
 }
 DEFINE_SIMPLE_ATTRIBUTE(fops_fpuemu_stat, fpuemu_stat_get, NULL, "%llu\n");
 
-extern struct dentry *mips_debugfs_dir;
 static int __init debugfs_fpuemu(void)
 {
 	struct dentry *d, *dir;