[PATCH v2 4/8] ocfs2: simplify subdirectory registration with register_sysctl()

[Luis Chamberlain]

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.

// pycocci sysctl-subdir-register-sysctl-simplify.cocci PATH

@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,
-       },
-       { }
-};

@initialize:python@
@@

def make_my_fresh_expression(s1, s2):
  return '"' + s1.strip('"') + "/" + s2.strip('"') + '"'

@r3 depends on c1 && c2 && c3@
expression c1.E1;
identifier c1.sysctls;
expression c2.E2;
identifier c2.base;
identifier c3.header;
fresh identifier E3 = script:python(E2, E1) { make_my_fresh_expression(E2, E1) 
};
@@

header =
-register_sysctl_table(base);
+register_sysctl(E3, sysctls);

Generated-by: Coccinelle SmPL
Signed-off-by: Luis Chamberlain <mcg...@kernel.org>
---
 fs/ocfs2/stackglue.c | 25 +------------------------
 1 file changed, 1 insertion(+), 24 deletions(-)

diff --git a/fs/ocfs2/stackglue.c b/fs/ocfs2/stackglue.c
index 16f1bfc407f2..731558a6f27d 100644
--- a/fs/ocfs2/stackglue.c
+++ b/fs/ocfs2/stackglue.c
@@ -672,31 +672,8 @@ 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
-       },
-       { }
-};
-
 static struct ctl_table_header *ocfs2_table_header;
 
-
 /*
  * Initialization
  */
@@ -705,7 +682,7 @@ 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("fs/ocfs2", ocfs2_mod_table);
        if (!ocfs2_table_header) {
                printk(KERN_ERR
                       "ocfs2 stack glue: unable to register sysctl\n");
-- 
2.33.0