Commit b2f56e55 authored by Luis Chamberlain's avatar Luis Chamberlain
Browse files

proc_sysctl: move helper which creates required subdirectories 



Move the code which creates the subdirectories for a ctl table
into a helper routine so to make it easier to review. Document
the goal.

This creates no functional changes.

Reviewed-by: default avatarJohn Johansen <john.johansen@canonical.com>
Signed-off-by: default avatarLuis Chamberlain <mcgrof@kernel.org>
parent 67ff3228

fs/proc/proc_sysctl.c

+32 −24
Original line number Diff line number Diff line
@@ -1283,6 +1283,35 @@ static int insert_links(struct ctl_table_header *head) 
	return err;

}



/* Find the directory for the ctl_table. If one is not found create it. */

static struct ctl_dir *sysctl_mkdir_p(struct ctl_dir *dir, const char *path)

{

	const char *name, *nextname;



	for (name = path; name; name = nextname) {

		int namelen;

		nextname = strchr(name, '/');

		if (nextname) {

			namelen = nextname - name;

			nextname++;

		} else {

			namelen = strlen(name);

		}

		if (namelen == 0)

			continue;



		/*

		 * namelen ensures if name is "foo/bar/yay" only foo is

		 * registered first. We traverse as if using mkdir -p and

		 * return a ctl_dir for the last directory entry.

		 */

		dir = get_subdir(dir, name, namelen);

		if (IS_ERR(dir))

			break;

	}

	return dir;

}



/**

 * __register_sysctl_table - register a leaf sysctl table

 * @set: Sysctl tree to register on
@@ -1334,7 +1363,6 @@ struct ctl_table_header *__register_sysctl_table( 
{

	struct ctl_table_root *root = set->dir.header.root;

	struct ctl_table_header *header;

	const char *name, *nextname;

	struct ctl_dir *dir;

	struct ctl_table *entry;

	struct ctl_node *node;
@@ -1359,29 +1387,9 @@ struct ctl_table_header *__register_sysctl_table( 
	dir->header.nreg++;

	spin_unlock(&sysctl_lock);



	/* Find the directory for the ctl_table */

	for (name = path; name; name = nextname) {

		int namelen;

		nextname = strchr(name, '/');

		if (nextname) {

			namelen = nextname - name;

			nextname++;

		} else {

			namelen = strlen(name);

		}

		if (namelen == 0)

			continue;



		/*

		 * namelen ensures if name is "foo/bar/yay" only foo is

		 * registered first. We traverse as if using mkdir -p and

		 * return a ctl_dir for the last directory entry.

		 */

		dir = get_subdir(dir, name, namelen);

	dir = sysctl_mkdir_p(dir, path);

	if (IS_ERR(dir))

		goto fail;

	}



	spin_lock(&sysctl_lock);

	if (insert_header(dir, header))

		goto fail_put_dir_locked;