Subject: [PATCH 06/13] ocfs2: use new sysctl subdir helper register_sysctl_subdir()

From: Luis Chamberlain <[email-masked]>
Date: Fri, 29 May 2020 07:41:01 +0000

This simplifies the code considerably. The following coccinelle
SmPL grammar rule was used to transform this code.

// pycocci sysctl-subdir.cocci fs/ocfs2/stackglue.c

@c1@
expression E1;
identifier subdir, sysctls;
@@

static struct ctl_table subdir[] = {
	{
		.procname = E1,
		.maxlen = 0,
		.mode = 0555,
		.child = sysctls,
	},
	{ }
};

@c2@
identifier c1.subdir;

expression E2;
identifier base;
@@

static struct ctl_table base[] = {
	{
		.procname = E2,
		.maxlen = 0,
		.mode = 0555,
		.child = subdir,
	},
	{ }
};

@c3@
identifier c2.base;
identifier header;
@@

header = register_sysctl_table(base);

@r1 depends on c1 && c2 && c3@
expression c1.E1;
identifier c1.subdir, c1.sysctls;
@@

-static struct ctl_table subdir[] = {
-	{
-		.procname = E1,
-		.maxlen = 0,
-		.mode = 0555,
-		.child = sysctls,
-	},
-	{ }
-};

@r2 depends on c1 && c2 && c3@
identifier c1.subdir;

expression c2.E2;
identifier c2.base;
@@
-static struct ctl_table base[] = {
-	{
-		.procname = E2,
-		.maxlen = 0,
-		.mode = 0555,
-		.child = subdir,
-	},
-	{ }
-};

@r3 depends on c1 && c2 && c3@
expression c1.E1;
identifier c1.sysctls;
expression c2.E2;
identifier c2.base;
identifier c3.header;
@@

header =
-register_sysctl_table(base);
+register_sysctl_subdir(E2, E1, sysctls);

Generated-by: Coccinelle SmPL

Signed-off-by: Luis Chamberlain <[email-masked]>
---
 fs/ocfs2/stackglue.c | 27 ++++-----------------------
 1 file changed, 4 insertions(+), 23 deletions(-)

diff --git a/fs/ocfs2/stackglue.c b/fs/ocfs2/stackglue.c
index a191094694c6..addafced7f59 100644
--- a/fs/ocfs2/stackglue.c
+++ b/fs/ocfs2/stackglue.c
@@ -677,28 +677,8 @@ static struct ctl_table ocfs2_mod_table[] = {
 	},
 	{ }
 };
-
-static struct ctl_table ocfs2_kern_table[] = {
-	{
-		.procname	= "ocfs2",
-		.data		= NULL,
-		.maxlen		= 0,
-		.mode		= 0555,
-		.child		= ocfs2_mod_table
-	},
-	{ }
-};
-
-static struct ctl_table ocfs2_root_table[] = {
-	{
-		.procname	= "fs",
-		.data		= NULL,
-		.maxlen		= 0,
-		.mode		= 0555,
-		.child		= ocfs2_kern_table
-	},
-	{ }
-};
+	.data		= NULL,
+	.data		= NULL,
 
 static struct ctl_table_header *ocfs2_table_header;
 
@@ -711,7 +691,8 @@ static int __init ocfs2_stack_glue_init(void)
 {
 	strcpy(cluster_stack_name, OCFS2_STACK_PLUGIN_O2CB);
 
-	ocfs2_table_header = register_sysctl_table(ocfs2_root_table);
+	ocfs2_table_header = register_sysctl_subdir("fs", "ocfs2",
+						    ocfs2_mod_table);
 	if (!ocfs2_table_header) {
 		printk(KERN_ERR
 		       "ocfs2 stack glue: unable to register sysctl\n");
-- 
2.26.2