Re: [PATCH v2 6/8] inotify: simplify subdirectory registration with register_sysctl()

Jan Kara
2021-11-24T09:44:15Z

On Tue 23-11-21 12:24:20, Luis Chamberlain wrote:
> From: Xiaoming Ni <nixiaoming@huawei.com>
>
> 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.
>
> Signed-off-by: Xiaoming Ni <nixiaoming@huawei.com>
> [mcgrof: update commit log to reflect new path we decided to take]
> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>

This looks fishy. You register inotify_table but not fanotify_table and
remove both...

Honza

> ---
> fs/notify/inotify/inotify_user.c | 11 ++++++++++-
> include/linux/inotify.h | 3 ---
> kernel/sysctl.c | 21 ---------------------
> 3 files changed, 10 insertions(+), 25 deletions(-)
>
> diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c
> index 29fca3284bb5..54583f62dc44 100644
> --- 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/inotify.h b/include/linux/inotify.h
> index 6a24905f6e1e..8d20caa1b268 100644
> --- 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 7a90a12b9ea4..6aa67c737e4e 100644
> --- a/kernel/sysctl.c
> +++ b/kernel/sysctl.c
> @@ -125,13 +125,6 @@ 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
>
> /**
> @@ -3099,20 +3092,6 @@ 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",
> --
> 2.33.0
>
--
Jan Kara <jack@suse.com>
SUSE Labs, CR