From: Xiaoming Ni <nixiaoming@xxxxxxxxxx> Subject: 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@xxxxxxxxxx: remember to register fanotify_table] Link: https://lkml.kernel.org/r/YZ5A6iWLb0h3N3RC@xxxxxxxxxxxxxxxxxxxxxx [mcgrof@xxxxxxxxxx: update commit log to reflect new path we decided to take] Link: https://lkml.kernel.org/r/20211123202422.819032-7-mcgrof@xxxxxxxxxx Signed-off-by: Xiaoming Ni <nixiaoming@xxxxxxxxxx> Signed-off-by: Luis Chamberlain <mcgrof@xxxxxxxxxx> Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx> Cc: Amir Goldstein <amir73il@xxxxxxxxx> Cc: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> Cc: Antti Palosaari <crope@xxxxxx> Cc: Arnd Bergmann <arnd@xxxxxxxx> Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> Cc: Benjamin LaHaise <bcrl@xxxxxxxxx> Cc: Clemens Ladisch <clemens@xxxxxxxxxx> Cc: David Airlie <airlied@xxxxxxxx> Cc: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Cc: Iurii Zaikin <yzaikin@xxxxxxxxxx> Cc: Jani Nikula <jani.nikula@xxxxxxxxxxxxxxx> Cc: Jan Kara <jack@xxxxxxx> Cc: Joel Becker <jlbec@xxxxxxxxxxxx> Cc: Joonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx> Cc: Joseph Qi <joseph.qi@xxxxxxxxxxxxxxxxx> Cc: Julia Lawall <julia.lawall@xxxxxxxx> Cc: Kees Cook <keescook@xxxxxxxxxxxx> Cc: Lukas Middendorf <kernel@xxxxxxxxxxx> Cc: Mark Fasheh <mark@xxxxxxxxxx> Cc: Paul Turner <pjt@xxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Petr Mladek <pmladek@xxxxxxxx> Cc: Phillip Potter <phil@xxxxxxxxxxxxxxxx> Cc: Qing Wang <wangqing@xxxxxxxx> Cc: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx> Cc: Sebastian Reichel <sre@xxxxxxxxxx> Cc: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx> Cc: Stephen Kitt <steve@xxxxxxx> Cc: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx> Cc: Douglas Gilbert <dgilbert@xxxxxxxxxxxx> Cc: James E.J. Bottomley <jejb@xxxxxxxxxxxxx> Cc: Jani Nikula <jani.nikula@xxxxxxxxx> Cc: John Ogness <john.ogness@xxxxxxxxxxxxx> Cc: Martin K. Petersen <martin.petersen@xxxxxxxxxx> Cc: "Rafael J. Wysocki" <rafael@xxxxxxxxxx> Cc: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx> Cc: Suren Baghdasaryan <surenb@xxxxxxxxxx> Cc: "Theodore Ts'o" <tytso@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- fs/notify/fanotify/fanotify_user.c | 10 +++++++++- fs/notify/inotify/inotify_user.c | 11 ++++++++++- include/linux/fanotify.h | 2 -- include/linux/inotify.h | 3 --- kernel/sysctl.c | 21 --------------------- 5 files changed, 19 insertions(+), 28 deletions(-) --- a/fs/notify/fanotify/fanotify_user.c~inotify-simplify-subdirectory-registration-with-register_sysctl +++ a/fs/notify/fanotify/fanotify_user.c @@ -59,7 +59,7 @@ static int fanotify_max_queued_events __ 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(vo 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; } --- a/fs/notify/inotify/inotify_user.c~inotify-simplify-subdirectory-registration-with-register_sysctl +++ a/fs/notify/inotify/inotify_user.c @@ -58,7 +58,7 @@ struct kmem_cache *inotify_inode_mark_ca 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(voi 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; } --- a/include/linux/fanotify.h~inotify-simplify-subdirectory-registration-with-register_sysctl +++ a/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)) --- a/include/linux/inotify.h~inotify-simplify-subdirectory-registration-with-register_sysctl +++ a/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 | \ --- a/kernel/sysctl.c~inotify-simplify-subdirectory-registration-with-register_sysctl +++ a/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", _
