From b2f56e5574eac0cf9e3dc382bef010298cb1f1e9 Mon Sep 17 00:00:00 2001 From: Luis Chamberlain Date: Thu, 2 Mar 2023 12:28:17 -0800 Subject: 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: John Johansen Signed-off-by: Luis Chamberlain --- fs/proc/proc_sysctl.c | 56 +++++++++++++++++++++++++++++---------------------- 1 file changed, 32 insertions(+), 24 deletions(-) (limited to 'fs/proc/proc_sysctl.c') diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c index 1df0beb50dbe..6b9b2694d430 100644 --- a/fs/proc/proc_sysctl.c +++ b/fs/proc/proc_sysctl.c @@ -1283,6 +1283,35 @@ out: 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); - if (IS_ERR(dir)) - goto fail; - } - + 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; -- cgit