[PATCH] beginning of sysctl cleanup - ctl_table_set

New object: set of sysctls [currently - root and per-net-ns].
Contains: pointer to parent set, list of tables and "should I see this set?"
method (->is_seen(set)).
Current lists of tables are subsumed by that; net-ns contains such a beast.
->lookup() for ctl_table_root returns pointer to ctl_table_set instead of
that to ->list of that ctl_table_set.

[folded compile fixes by rdd for configs without sysctl]

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 10 insertions, 12 deletions

diff --git a/net/sysctl_net.c b/net/sysctl_net.c
index 63ada437fc2f..cefbc367d8be 100644
--- a/net/sysctl_net.c
+++ b/net/sysctl_net.c
@@ -29,10 +29,15 @@
 #include <linux/if_tr.h>
 #endif
 
-static struct list_head *
+static struct ctl_table_set *
 net_ctl_header_lookup(struct ctl_table_root *root, struct nsproxy *namespaces)
 {
-        return &namespaces->net_ns->sysctl_table_headers;
+        return &namespaces->net_ns->sysctls;
+}
+
+static int is_seen(struct ctl_table_set *set)
+{
+        return &current->nsproxy->net_ns->sysctls == set;
 }
 
 /* Return standard mode bits for table entry. */
@@ -53,13 +58,6 @@ static struct ctl_table_root net_sysctl_root = {
         .permissions = net_ctl_permissions,
 };
 
-static LIST_HEAD(net_sysctl_ro_tables);
-static struct list_head *net_ctl_ro_header_lookup(struct ctl_table_root *root,
-                struct nsproxy *namespaces)
-{
-        return &net_sysctl_ro_tables;
-}
-
 static int net_ctl_ro_header_perms(struct ctl_table_root *root,
                 struct nsproxy *namespaces, struct ctl_table *table)
 {
@@ -70,19 +68,18 @@ static int net_ctl_ro_header_perms(struct ctl_table_root *root,
 }
 
 static struct ctl_table_root net_sysctl_ro_root = {
-        .lookup = net_ctl_ro_header_lookup,
         .permissions = net_ctl_ro_header_perms,
 };
 
 static int sysctl_net_init(struct net *net)
 {
-        INIT_LIST_HEAD(&net->sysctl_table_headers);
+        setup_sysctl_set(&net->sysctls, NULL, is_seen);
         return 0;
 }
 
 static void sysctl_net_exit(struct net *net)
 {
-        WARN_ON(!list_empty(&net->sysctl_table_headers));
+        WARN_ON(!list_empty(&net->sysctls.list));
         return;
 }
 
@@ -98,6 +95,7 @@ static __init int sysctl_init(void)
         if (ret)
                 goto out;
         register_sysctl_root(&net_sysctl_root);
+        setup_sysctl_set(&net_sysctl_ro_root.default_set, NULL, NULL);
         register_sysctl_root(&net_sysctl_ro_root);
 out:
         return ret;