inotify: simplify subdirectory registration with register_sysctl()

There is no need to user boiler plate code to specify a set of base
directories we're going to stuff sysctls under.  Simplify this by using
register_sysctl() and specifying the directory path directly.

Move inotify_user sysctl to inotify_user.c while at it to remove clutter
from kernel/sysctl.c.

[mcgrof@kernel.org: remember to register fanotify_table]
Link: https://lkml.kernel.org/r/YZ5A6iWLb0h3N3RC@bombadil.infradead.org
[mcgrof@kernel.org: update commit log to reflect new path we decided to take]

Link: https://lkml.kernel.org/r/20211123202422.819032-7-mcgrof@kernel.org
Signed-off-by: Xiaoming Ni <nixiaoming@huawei.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Amir Goldstein <amir73il@gmail.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Antti Palosaari <crope@iki.fi>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Benjamin LaHaise <bcrl@kvack.org>
Cc: Clemens Ladisch <clemens@ladisch.de>
Cc: David Airlie <airlied@linux.ie>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Julia Lawall <julia.lawall@inria.fr>
Cc: Kees Cook <keescook@chromium.org>
Cc: Lukas Middendorf <kernel@tuxforce.de>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Phillip Potter <phil@philpotter.co.uk>
Cc: Qing Wang <wangqing@vivo.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Sebastian Reichel <sre@kernel.org>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Stephen Kitt <steve@sk2.org>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Cc: James E.J. Bottomley <jejb@linux.ibm.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: John Ogness <john.ogness@linutronix.de>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
index 73a3e939c9216004b496ae4936e69c3166865818..73b1615f9d962d9adf56b061c5d37c08e4ad155d 100644 (file)
--- a/fs/notify/fanotify/fanotify_user.c
+++ b/fs/notify/fanotify/fanotify_user.c
@@ -59,7 +59,7 @@ static int fanotify_max_queued_events __read_mostly;
 static long ft_zero = 0;
 static long ft_int_max = INT_MAX;
 
-struct ctl_table fanotify_table[] = {
+static struct ctl_table fanotify_table[] = {
        {
                .procname       = "max_user_groups",
                .data   = &init_user_ns.ucount_max[UCOUNT_FANOTIFY_GROUPS],
@@ -88,6 +88,13 @@ struct ctl_table fanotify_table[] = {
        },
        { }
 };
+
+static void __init fanotify_sysctls_init(void)
+{
+       register_sysctl("fs/fanotify", fanotify_table);
+}
+#else
+#define fanotify_sysctls_init() do { } while (0)
 #endif /* CONFIG_SYSCTL */
 
 /*
@@ -1743,6 +1750,7 @@ static int __init fanotify_user_setup(void)
        init_user_ns.ucount_max[UCOUNT_FANOTIFY_GROUPS] =
                                        FANOTIFY_DEFAULT_MAX_GROUPS;
        init_user_ns.ucount_max[UCOUNT_FANOTIFY_MARKS] = max_marks;
+       fanotify_sysctls_init();
 
        return 0;
 }

diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c
index 29fca3284bb5c83c25a669b213dfa3da870631ed..54583f62dc4403b37ec7a073ae61a16ce055733e 100644 (file)
--- a/fs/notify/inotify/inotify_user.c
+++ b/fs/notify/inotify/inotify_user.c
@@ -58,7 +58,7 @@ struct kmem_cache *inotify_inode_mark_cachep __read_mostly;
 static long it_zero = 0;
 static long it_int_max = INT_MAX;
 
-struct ctl_table inotify_table[] = {
+static struct ctl_table inotify_table[] = {
        {
                .procname       = "max_user_instances",
                .data           = &init_user_ns.ucount_max[UCOUNT_INOTIFY_INSTANCES],
@@ -87,6 +87,14 @@ struct ctl_table inotify_table[] = {
        },
        { }
 };
+
+static void __init inotify_sysctls_init(void)
+{
+       register_sysctl("fs/inotify", inotify_table);
+}
+
+#else
+#define inotify_sysctls_init() do { } while (0)
 #endif /* CONFIG_SYSCTL */
 
 static inline __u32 inotify_arg_to_mask(struct inode *inode, u32 arg)
@@ -849,6 +857,7 @@ static int __init inotify_user_setup(void)
        inotify_max_queued_events = 16384;
        init_user_ns.ucount_max[UCOUNT_INOTIFY_INSTANCES] = 128;
        init_user_ns.ucount_max[UCOUNT_INOTIFY_WATCHES] = watches_max;
+       inotify_sysctls_init();
 
        return 0;
 }

diff --git a/include/linux/fanotify.h b/include/linux/fanotify.h
index 3afdf339d53c937c3e864b2448731803f90a51f2..419cadcd7ff55d1a2a108ca00ee5a2c326aa740c 100644 (file)
--- a/include/linux/fanotify.h
+++ b/include/linux/fanotify.h
@@ -5,8 +5,6 @@
 #include <linux/sysctl.h>
 #include <uapi/linux/fanotify.h>
 
-extern struct ctl_table fanotify_table[]; /* for sysctl */
-
 #define FAN_GROUP_FLAG(group, flag) \
        ((group)->fanotify_data.flags & (flag))
 

diff --git a/include/linux/inotify.h b/include/linux/inotify.h
index 6a24905f6e1e2964ecea4487e3140913d4bccc57..8d20caa1b2687b76ac3399ae1006f90d3026dbe3 100644 (file)
--- a/include/linux/inotify.h
+++ b/include/linux/inotify.h
@@ -7,11 +7,8 @@
 #ifndef _LINUX_INOTIFY_H
 #define _LINUX_INOTIFY_H
 
-#include <linux/sysctl.h>
 #include <uapi/linux/inotify.h>
 
-extern struct ctl_table inotify_table[]; /* for sysctl */
-
 #define ALL_INOTIFY_BITS (IN_ACCESS | IN_MODIFY | IN_ATTRIB | IN_CLOSE_WRITE | \
                          IN_CLOSE_NOWRITE | IN_OPEN | IN_MOVED_FROM | \
                          IN_MOVED_TO | IN_CREATE | IN_DELETE | \

diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index fb37825cd3cd6318c3edc793bcbd7d6c7f8bdd0b..2ee0e76888d8a11600500fa1966ab7360dc12468 100644 (file)
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -126,13 +126,6 @@ static const int maxolduid = 65535;
 static const int ngroups_max = NGROUPS_MAX;
 static const int cap_last_cap = CAP_LAST_CAP;
 
-#ifdef CONFIG_INOTIFY_USER
-#include <linux/inotify.h>
-#endif
-#ifdef CONFIG_FANOTIFY
-#include <linux/fanotify.h>
-#endif
-
 #ifdef CONFIG_PROC_SYSCTL
 
 /**
@@ -3100,20 +3093,6 @@ static struct ctl_table fs_table[] = {
                .proc_handler   = proc_dointvec,
        },
 #endif
-#ifdef CONFIG_INOTIFY_USER
-       {
-               .procname       = "inotify",
-               .mode           = 0555,
-               .child          = inotify_table,
-       },
-#endif
-#ifdef CONFIG_FANOTIFY
-       {
-               .procname       = "fanotify",
-               .mode           = 0555,
-               .child          = fanotify_table,
-       },
-#endif
 #ifdef CONFIG_EPOLL
        {
                .procname       = "epoll",