dnotify: move dnotify sysctl to dnotify.c

The kernel/sysctl.c is a kitchen sink where everyone leaves their dirty
dishes, this makes it very difficult to maintain.

To help with this maintenance let's start by moving sysctls to places
where they actually belong.  The proc sysctl maintainers do not want to
know what sysctl knobs you wish to add for your own piece of code, we
just care about the core logic.

So move dnotify sysctls to dnotify.c and use the new
register_sysctl_init() to register the sysctl interface.

[[email protected]: adjust the commit log to justify the move]

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Xiaoming Ni <[email protected]>
Signed-off-by: Luis Chamberlain <[email protected]>
Acked-by: Jan Kara <[email protected]>
Cc: Al Viro <[email protected]>
Cc: Amir Goldstein <[email protected]>
Cc: Andy Shevchenko <[email protected]>
Cc: Benjamin LaHaise <[email protected]>
Cc: "Eric W. Biederman" <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Iurii Zaikin <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Paul Turner <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Petr Mladek <[email protected]>
Cc: Qing Wang <[email protected]>
Cc: Sebastian Reichel <[email protected]>
Cc: Sergey Senozhatsky <[email protected]>
Cc: Stephen Kitt <[email protected]>
Cc: Tetsuo Handa <[email protected]>
Cc: Antti Palosaari <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Benjamin Herrenschmidt <[email protected]>
Cc: Clemens Ladisch <[email protected]>
Cc: David Airlie <[email protected]>
Cc: Jani Nikula <[email protected]>
Cc: Joel Becker <[email protected]>
Cc: Joonas Lahtinen <[email protected]>
Cc: Joseph Qi <[email protected]>
Cc: Julia Lawall <[email protected]>
Cc: Lukas Middendorf <[email protected]>
Cc: Mark Fasheh <[email protected]>
Cc: Phillip Potter <[email protected]>
Cc: Rodrigo Vivi <[email protected]>
Cc: Douglas Gilbert <[email protected]>
Cc: James E.J. Bottomley <[email protected]>
Cc: Jani Nikula <[email protected]>
Cc: John Ogness <[email protected]>
Cc: Martin K. Petersen <[email protected]>
Cc: "Rafael J. Wysocki" <[email protected]>
Cc: Steven Rostedt (VMware) <[email protected]>
Cc: Suren Baghdasaryan <[email protected]>
Cc: "Theodore Ts'o" <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

3 files changed, 20 insertions, 12 deletions

diff --git a/fs/notify/dnotify/dnotify.c b/fs/notify/dnotify/dnotify.c
index d5ebebb034ff..829dd4a61b66 100644
--- a/fs/notify/dnotify/dnotify.c
+++ b/fs/notify/dnotify/dnotify.c
@@ -19,7 +19,25 @@
 #include <linux/fdtable.h>
 #include <linux/fsnotify_backend.h>
 
-int dir_notify_enable __read_mostly = 1;
+static int dir_notify_enable __read_mostly = 1;
+#ifdef CONFIG_SYSCTL
+static struct ctl_table dnotify_sysctls[] = {
+	{
+		.procname	= "dir-notify-enable",
+		.data		= &dir_notify_enable,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec,
+	},
+	{}
+};
+static void __init dnotify_sysctl_init(void)
+{
+	register_sysctl_init("fs", dnotify_sysctls);
+}
+#else
+#define dnotify_sysctl_init() do { } while (0)
+#endif
 
 static struct kmem_cache *dnotify_struct_cache __read_mostly;
 static struct kmem_cache *dnotify_mark_cache __read_mostly;
@@ -386,6 +404,7 @@ static int __init dnotify_init(void)
 	dnotify_group = fsnotify_alloc_group(&dnotify_fsnotify_ops);
 	if (IS_ERR(dnotify_group))
 		panic("unable to allocate fsnotify group for dnotify\n");
+	dnotify_sysctl_init();
 	return 0;
 }
 
diff --git a/include/linux/dnotify.h b/include/linux/dnotify.h
index b87c3b85a166..b1d26f9f1c9f 100644
--- a/include/linux/dnotify.h
+++ b/include/linux/dnotify.h
@@ -29,7 +29,6 @@ struct dnotify_struct {
 			    FS_CREATE | FS_RENAME |\
 			    FS_MOVED_FROM | FS_MOVED_TO)
 
-extern int dir_notify_enable;
 extern void dnotify_flush(struct file *, fl_owner_t);
 extern int fcntl_dirnotify(int, struct file *, unsigned long);
 
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 822555a0ec76..fb37825cd3cd 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -49,7 +49,6 @@
 #include <linux/times.h>
 #include <linux/limits.h>
 #include <linux/dcache.h>
-#include <linux/dnotify.h>
 #include <linux/syscalls.h>
 #include <linux/vmstat.h>
 #include <linux/nfs_fs.h>
@@ -3091,15 +3090,6 @@ static struct ctl_table fs_table[] = {
 		.proc_handler	= proc_dointvec,
 	},
 #endif
-#ifdef CONFIG_DNOTIFY
-	{
-		.procname	= "dir-notify-enable",
-		.data		= &dir_notify_enable,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
-	},
-#endif
 #ifdef CONFIG_MMU
 #ifdef CONFIG_FILE_LOCKING
 	{