knfsd: allow cache_register to return error on failure

Newer server features such as nfsv4 and gss depend on proc to work, so a
failure to initialize the proc files they need should be treated as
fatal.

Thanks to Andrew Morton for style fix and compile fix in case where
CONFIG_NFSD_V4 is undefined.

Cc: Andrew Morton <akpm@linux-foundation.org>
Acked-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

2 files changed, 36 insertions, 11 deletions

diff --git a/net/sunrpc/auth_gss/svcauth_gss.c b/net/sunrpc/auth_gss/svcauth_gss.c
index d329a12500aa..aa790bb4f7a1 100644
--- a/net/sunrpc/auth_gss/svcauth_gss.c
+++ b/net/sunrpc/auth_gss/svcauth_gss.c
@@ -1386,10 +1386,19 @@ int
 gss_svc_init(void)
 {
         int rv = svc_auth_register(RPC_AUTH_GSS, &svcauthops_gss);
-        if (rv == 0) {
-                cache_register(&rsc_cache);
-                cache_register(&rsi_cache);
-        }
+        if (rv)
+                return rv;
+        rv = cache_register(&rsc_cache);
+        if (rv)
+                goto out1;
+        rv = cache_register(&rsi_cache);
+        if (rv)
+                goto out2;
+        return 0;
+out2:
+        cache_unregister(&rsc_cache);
+out1:
+        svc_auth_unregister(RPC_AUTH_GSS);
         return rv;
 }
 
diff --git a/net/sunrpc/cache.c b/net/sunrpc/cache.c
index f41a7cc4cf62..50b1a8b441fe 100644
--- a/net/sunrpc/cache.c
+++ b/net/sunrpc/cache.c
@@ -304,20 +304,21 @@ static void remove_cache_proc_entries(struct cache_detail *cd)
         remove_proc_entry(cd->name, proc_net_rpc);
 }
 
-static void create_cache_proc_entries(struct cache_detail *cd)
+#ifdef CONFIG_PROC_FS
+static int create_cache_proc_entries(struct cache_detail *cd)
 {
         struct proc_dir_entry *p;
 
         cd->proc_ent = proc_mkdir(cd->name, proc_net_rpc);
         if (cd->proc_ent == NULL)
-                return;
+                goto out_nomem;
         cd->proc_ent->owner = cd->owner;
         cd->channel_ent = cd->content_ent = NULL;
 
         p = create_proc_entry("flush", S_IFREG|S_IRUSR|S_IWUSR, cd->proc_ent);
         cd->flush_ent = p;
         if (p == NULL)
-                return;
+                goto out_nomem;
         p->proc_fops = &cache_flush_operations;
         p->owner = cd->owner;
         p->data = cd;
@@ -327,7 +328,7 @@ static void create_cache_proc_entries(struct cache_detail *cd)
                                       cd->proc_ent);
                 cd->channel_ent = p;
                 if (p == NULL)
-                        return;
+                        goto out_nomem;
                 p->proc_fops = &cache_file_operations;
                 p->owner = cd->owner;
                 p->data = cd;
@@ -337,16 +338,30 @@ static void create_cache_proc_entries(struct cache_detail *cd)
                                       cd->proc_ent);
                 cd->content_ent = p;
                 if (p == NULL)
-                        return;
+                        goto out_nomem;
                 p->proc_fops = &content_file_operations;
                 p->owner = cd->owner;
                 p->data = cd;
         }
+        return 0;
+out_nomem:
+        remove_cache_proc_entries(cd);
+        return -ENOMEM;
 }
+#else /* CONFIG_PROC_FS */
+static int create_cache_proc_entries(struct cache_detail *cd)
+{
+        return 0;
+}
+#endif
 
-void cache_register(struct cache_detail *cd)
+int cache_register(struct cache_detail *cd)
 {
-        create_cache_proc_entries(cd);
+        int ret;
+
+        ret = create_cache_proc_entries(cd);
+        if (ret)
+                return ret;
         rwlock_init(&cd->hash_lock);
         INIT_LIST_HEAD(&cd->queue);
         spin_lock(&cache_list_lock);
@@ -360,6 +375,7 @@ void cache_register(struct cache_detail *cd)
 
         /* start the cleaning process */
         schedule_delayed_work(&cache_cleaner, 0);
+        return 0;
 }
 
 void cache_unregister(struct cache_detail *cd)