fs: move pipe sysctls to is own file

The 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 pipe sysctls to its own file.

Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>

3 files changed, 70 insertions, 54 deletions

diff --git a/fs/pipe.c b/fs/pipe.c
index 6d4342bad9f15..ec757d30c7960 100644
--- a/fs/pipe.c
+++ b/fs/pipe.c
@@ -25,6 +25,7 @@
 #include <linux/fcntl.h>
 #include <linux/memcontrol.h>
 #include <linux/watch_queue.h>
+#include <linux/sysctl.h>
 
 #include <linux/uaccess.h>
 #include <asm/ioctls.h>
@@ -1428,6 +1429,60 @@ static struct file_system_type pipe_fs_type = {
 	.kill_sb	= kill_anon_super,
 };
 
+#ifdef CONFIG_SYSCTL
+static int do_proc_dopipe_max_size_conv(unsigned long *lvalp,
+					unsigned int *valp,
+					int write, void *data)
+{
+	if (write) {
+		unsigned int val;
+
+		val = round_pipe_size(*lvalp);
+		if (val == 0)
+			return -EINVAL;
+
+		*valp = val;
+	} else {
+		unsigned int val = *valp;
+		*lvalp = (unsigned long) val;
+	}
+
+	return 0;
+}
+
+static int proc_dopipe_max_size(struct ctl_table *table, int write,
+				void *buffer, size_t *lenp, loff_t *ppos)
+{
+	return do_proc_douintvec(table, write, buffer, lenp, ppos,
+				 do_proc_dopipe_max_size_conv, NULL);
+}
+
+static struct ctl_table fs_pipe_sysctls[] = {
+	{
+		.procname	= "pipe-max-size",
+		.data		= &pipe_max_size,
+		.maxlen		= sizeof(pipe_max_size),
+		.mode		= 0644,
+		.proc_handler	= proc_dopipe_max_size,
+	},
+	{
+		.procname	= "pipe-user-pages-hard",
+		.data		= &pipe_user_pages_hard,
+		.maxlen		= sizeof(pipe_user_pages_hard),
+		.mode		= 0644,
+		.proc_handler	= proc_doulongvec_minmax,
+	},
+	{
+		.procname	= "pipe-user-pages-soft",
+		.data		= &pipe_user_pages_soft,
+		.maxlen		= sizeof(pipe_user_pages_soft),
+		.mode		= 0644,
+		.proc_handler	= proc_doulongvec_minmax,
+	},
+	{ }
+};
+#endif
+
 static int __init init_pipe_fs(void)
 {
 	int err = register_filesystem(&pipe_fs_type);
@@ -1439,6 +1494,9 @@ static int __init init_pipe_fs(void)
 			unregister_filesystem(&pipe_fs_type);
 		}
 	}
+#ifdef CONFIG_SYSCTL
+	register_sysctl_init("fs", fs_pipe_sysctls, "pipe_sysctls");
+#endif
 	return err;
 }
 
diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h
index 43bb8e1cb42a6..b7af577086eee 100644
--- a/include/linux/sysctl.h
+++ b/include/linux/sysctl.h
@@ -219,6 +219,12 @@ extern void __register_sysctl_init(const char *path, struct ctl_table *table,
 				 const char *table_name);
 #define register_sysctl_init(path, table) __register_sysctl_init(path, table, #table)
 void do_sysctl_args(void);
+int do_proc_douintvec(struct ctl_table *table, int write,
+		      void *buffer, size_t *lenp, loff_t *ppos,
+		      int (*conv)(unsigned long *lvalp,
+				  unsigned int *valp,
+				  int write, void *data),
+		      void *data);
 
 extern int pwrsw_enabled;
 extern int unaligned_enabled;
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 5d6efc3406639..d6586b3bcc3a6 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -760,12 +760,12 @@ static int __do_proc_douintvec(void *tbl_data, struct ctl_table *table,
 	return do_proc_douintvec_r(i, buffer, lenp, ppos, conv, data);
 }
 
-static int do_proc_douintvec(struct ctl_table *table, int write,
-			     void *buffer, size_t *lenp, loff_t *ppos,
-			     int (*conv)(unsigned long *lvalp,
-					 unsigned int *valp,
-					 int write, void *data),
-			     void *data)
+int do_proc_douintvec(struct ctl_table *table, int write,
+		      void *buffer, size_t *lenp, loff_t *ppos,
+		      int (*conv)(unsigned long *lvalp,
+				  unsigned int *valp,
+				  int write, void *data),
+		      void *data)
 {
 	return __do_proc_douintvec(table->data, table, write,
 				   buffer, lenp, ppos, conv, data);
@@ -1089,33 +1089,6 @@ int proc_dou8vec_minmax(struct ctl_table *table, int write,
 }
 EXPORT_SYMBOL_GPL(proc_dou8vec_minmax);
 
-static int do_proc_dopipe_max_size_conv(unsigned long *lvalp,
-					unsigned int *valp,
-					int write, void *data)
-{
-	if (write) {
-		unsigned int val;
-
-		val = round_pipe_size(*lvalp);
-		if (val == 0)
-			return -EINVAL;
-
-		*valp = val;
-	} else {
-		unsigned int val = *valp;
-		*lvalp = (unsigned long) val;
-	}
-
-	return 0;
-}
-
-static int proc_dopipe_max_size(struct ctl_table *table, int write,
-				void *buffer, size_t *lenp, loff_t *ppos)
-{
-	return do_proc_douintvec(table, write, buffer, lenp, ppos,
-				 do_proc_dopipe_max_size_conv, NULL);
-}
-
 #ifdef CONFIG_MAGIC_SYSRQ
 static int sysrq_sysctl_handler(struct ctl_table *table, int write,
 				void *buffer, size_t *lenp, loff_t *ppos)
@@ -2840,27 +2813,6 @@ static struct ctl_table vm_table[] = {
 
 static struct ctl_table fs_table[] = {
 	{
-		.procname	= "pipe-max-size",
-		.data		= &pipe_max_size,
-		.maxlen		= sizeof(pipe_max_size),
-		.mode		= 0644,
-		.proc_handler	= proc_dopipe_max_size,
-	},
-	{
-		.procname	= "pipe-user-pages-hard",
-		.data		= &pipe_user_pages_hard,
-		.maxlen		= sizeof(pipe_user_pages_hard),
-		.mode		= 0644,
-		.proc_handler	= proc_doulongvec_minmax,
-	},
-	{
-		.procname	= "pipe-user-pages-soft",
-		.data		= &pipe_user_pages_soft,
-		.maxlen		= sizeof(pipe_user_pages_soft),
-		.mode		= 0644,
-		.proc_handler	= proc_doulongvec_minmax,
-	},
-	{
 		.procname	= "mount-max",
 		.data		= &sysctl_mount_max,
 		.maxlen		= sizeof(unsigned int),