From mboxrd@z Thu Jan 1 00:00:00 1970 From: Luis Chamberlain Date: Fri, 29 May 2020 07:41:07 +0000 Subject: [Ocfs2-devel] [PATCH 12/13] sysctl: add helper to register empty subdir In-Reply-To: <20200529074108.16928-1-mcgrof@kernel.org> References: <20200529074108.16928-1-mcgrof@kernel.org> Message-ID: <20200529074108.16928-13-mcgrof@kernel.org> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: keescook@chromium.org, yzaikin@google.com, nixiaoming@huawei.com, ebiederm@xmission.com, axboe@kernel.dk, clemens@ladisch.de, arnd@arndb.de, gregkh@linuxfoundation.org, jani.nikula@linux.intel.com, joonas.lahtinen@linux.intel.com, rodrigo.vivi@intel.com, airlied@linux.ie, daniel@ffwll.ch, benh@kernel.crashing.org, rdna@fb.com, viro@zeniv.linux.org.uk, mark@fasheh.com, jlbec@evilplan.org, joseph.qi@linux.alibaba.com, vbabka@suse.cz, sfr@canb.auug.org.au, jack@suse.cz, amir73il@gmail.com, rafael@kernel.org, tytso@mit.edu Cc: intel-gfx@lists.freedesktop.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, julia.lawall@lip6.fr, Luis Chamberlain , akpm@linux-foundation.org, linuxppc-dev@lists.ozlabs.org, ocfs2-devel@oss.oracle.com The way to create a subdirectory from the base set of directories is a bit obscure, so provide a helper which makes this clear, and also helps remove boiler plate code required to do this work. Signed-off-by: Luis Chamberlain --- include/linux/sysctl.h | 7 +++++++ kernel/sysctl.c | 16 +++++++++++++--- 2 files changed, 20 insertions(+), 3 deletions(-) diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h index 33a471b56345..89c92390e6de 100644 --- a/include/linux/sysctl.h +++ b/include/linux/sysctl.h @@ -208,6 +208,8 @@ extern void register_sysctl_init(const char *path, struct ctl_table *table, extern struct ctl_table_header *register_sysctl_subdir(const char *base, const char *subdir, struct ctl_table *table); +extern void register_sysctl_empty_subdir(const char *base, const char *subdir); + void do_sysctl_args(void); extern int pwrsw_enabled; @@ -231,6 +233,11 @@ inline struct ctl_table_header *register_sysctl_subdir(const char *base, return NULL; } +static inline void register_sysctl_empty_subdir(const char *base, + const char *subdir) +{ +} + static inline struct ctl_table_header *register_sysctl_paths( const struct ctl_path *path, struct ctl_table *table) { diff --git a/kernel/sysctl.c b/kernel/sysctl.c index f9a35325d5d5..460532cd5ac8 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -3188,13 +3188,17 @@ struct ctl_table_header *register_sysctl_subdir(const char *base, { } }; - if (!table->procname) + if (table != sysctl_mount_point && !table->procname) goto out; hdr = register_sysctl_table(base_table); if (unlikely(!hdr)) { - pr_err("failed when creating subdirectory sysctl %s/%s/%s\n", - base, subdir, table->procname); + if (table != sysctl_mount_point) + pr_err("failed when creating subdirectory sysctl %s/%s/%s\n", + base, subdir, table->procname); + else + pr_err("failed when creating empty subddirectory %s/%s\n", + base, subdir); goto out; } kmemleak_not_leak(hdr); @@ -3202,6 +3206,12 @@ struct ctl_table_header *register_sysctl_subdir(const char *base, return hdr; } EXPORT_SYMBOL_GPL(register_sysctl_subdir); + +void register_sysctl_empty_subdir(const char *base, + const char *subdir) +{ + register_sysctl_subdir(base, subdir, sysctl_mount_point); +} #endif /* CONFIG_SYSCTL */ /* * No sense putting this after each symbol definition, twice, -- 2.26.2