fs: move inode sysctls to its own file

Patch series "sysctl: 4th set of kernel/sysctl cleanups".

This is slimming down the fs uses of kernel/sysctl.c to the point that
the next step is to just get rid of the fs base directory for it and
move that elsehwere, so that next patch series starts dealing with that
to demo how we can end up cleaning up a full base directory from
kernel/sysctl.c, one at a time.

This patch (of 9):

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 the inode sysctls to its own file.  Since we are no longer using
this outside of fs/ remove the extern declaration of its respective proc
helper.

We use early_initcall() as it is the earliest we can use.

[arnd@arndb.de: avoid unused-variable warning]
Link: https://lkml.kernel.org/r/20211203190123.874239-1-arnd@kernel.org
Link: https://lkml.kernel.org/r/20211129205548.605569-1-mcgrof@kernel.org
Link: https://lkml.kernel.org/r/20211129205548.605569-2-mcgrof@kernel.org
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Kees Cook <keescook@chromium.org>
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Xiaoming Ni <nixiaoming@huawei.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Stephen Kitt <steve@sk2.org>
Cc: Lukas Middendorf <kernel@tuxforce.de>
Cc: Antti Palosaari <crope@iki.fi>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/fs/inode.c b/fs/inode.c
index 980e7b7a546077af6a79639889d85b0bcf95fc27..63324df6fa273426765c37e14f83ff2ecc93e1b8 100644 (file)
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -67,11 +67,6 @@ const struct address_space_operations empty_aops = {
 };
 EXPORT_SYMBOL(empty_aops);
 
-/*
- * Statistics gathering..
- */
-struct inodes_stat_t inodes_stat;
-
 static DEFINE_PER_CPU(unsigned long, nr_inodes);
 static DEFINE_PER_CPU(unsigned long, nr_unused);
 
@@ -106,13 +101,43 @@ long get_nr_dirty_inodes(void)
  * Handle nr_inode sysctl
  */
 #ifdef CONFIG_SYSCTL
-int proc_nr_inodes(struct ctl_table *table, int write,
-                  void *buffer, size_t *lenp, loff_t *ppos)
+/*
+ * Statistics gathering..
+ */
+static struct inodes_stat_t inodes_stat;
+
+static int proc_nr_inodes(struct ctl_table *table, int write, void *buffer,
+                         size_t *lenp, loff_t *ppos)
 {
        inodes_stat.nr_inodes = get_nr_inodes();
        inodes_stat.nr_unused = get_nr_inodes_unused();
        return proc_doulongvec_minmax(table, write, buffer, lenp, ppos);
 }
+
+static struct ctl_table inodes_sysctls[] = {
+       {
+               .procname       = "inode-nr",
+               .data           = &inodes_stat,
+               .maxlen         = 2*sizeof(long),
+               .mode           = 0444,
+               .proc_handler   = proc_nr_inodes,
+       },
+       {
+               .procname       = "inode-state",
+               .data           = &inodes_stat,
+               .maxlen         = 7*sizeof(long),
+               .mode           = 0444,
+               .proc_handler   = proc_nr_inodes,
+       },
+       { }
+};
+
+static int __init init_fs_inode_sysctls(void)
+{
+       register_sysctl_init("fs", inodes_sysctls);
+       return 0;
+}
+early_initcall(init_fs_inode_sysctls);
 #endif
 
 static int no_open(struct inode *inode, struct file *file)

diff --git a/include/linux/fs.h b/include/linux/fs.h
index c8510da6cc6dc88821b1265d9bb00357579a3dd1..044de67c8167280e999b07c8258be019d3599844 100644 (file)
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -82,7 +82,6 @@ extern void __init files_maxfiles_init(void);
 extern struct files_stat_struct files_stat;
 extern unsigned long get_max_files(void);
 extern unsigned int sysctl_nr_open;
-extern struct inodes_stat_t inodes_stat;
 extern int leases_enable, lease_break_time;
 extern int sysctl_protected_symlinks;
 extern int sysctl_protected_hardlinks;
@@ -3537,8 +3536,6 @@ int proc_nr_files(struct ctl_table *table, int write,
                  void *buffer, size_t *lenp, loff_t *ppos);
 int proc_nr_dentry(struct ctl_table *table, int write,
                  void *buffer, size_t *lenp, loff_t *ppos);
-int proc_nr_inodes(struct ctl_table *table, int write,
-                  void *buffer, size_t *lenp, loff_t *ppos);
 int __init list_bdev_fs_names(char *buf, size_t size);
 
 #define __FMODE_EXEC           ((__force int) FMODE_EXEC)

diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 1b8a1cb8aac993bc64fea4b60fe4fa5b02e30d15..402c9d3246bfb50b72985a639a7ffd824cc192f4 100644 (file)
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -2901,20 +2901,6 @@ static struct ctl_table vm_table[] = {
 };
 
 static struct ctl_table fs_table[] = {
-       {
-               .procname       = "inode-nr",
-               .data           = &inodes_stat,
-               .maxlen         = 2*sizeof(long),
-               .mode           = 0444,
-               .proc_handler   = proc_nr_inodes,
-       },
-       {
-               .procname       = "inode-state",
-               .data           = &inodes_stat,
-               .maxlen         = 7*sizeof(long),
-               .mode           = 0444,
-               .proc_handler   = proc_nr_inodes,
-       },
        {
                .procname       = "file-nr",
                .data           = &files_stat,