[PATCH] knfsd: Change the store of auth_domains to not be a 'cache'

The 'auth_domain's are simply handles on internal data structures.  They do
not cache information from user-space, and forcing them into the mold of a
'cache' misrepresents their true nature and causes confusion.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

6 files changed, 81 insertions, 145 deletions

diff --git a/fs/nfsd/export.c b/fs/nfsd/export.c
index 417ec02df44f..ac0997731fce 100644
--- a/fs/nfsd/export.c
+++ b/fs/nfsd/export.c
@@ -242,7 +242,7 @@ static inline int svc_expkey_match (struct svc_expkey *a, struct svc_expkey *b)
 
 static inline void svc_expkey_init(struct svc_expkey *new, struct svc_expkey *item)
 {
-        cache_get(&item->ek_client->h);
+        kref_get(&item->ek_client->ref);
         new->ek_client = item->ek_client;
         new->ek_fsidtype = item->ek_fsidtype;
         new->ek_fsid[0] = item->ek_fsid[0];
@@ -474,7 +474,7 @@ static inline int svc_export_match(struct svc_export *a, struct svc_export *b)
 }
 static inline void svc_export_init(struct svc_export *new, struct svc_export *item)
 {
-        cache_get(&item->ex_client->h);
+        kref_get(&item->ex_client->ref);
         new->ex_client = item->ex_client;
         new->ex_dentry = dget(item->ex_dentry);
         new->ex_mnt = mntget(item->ex_mnt);
@@ -1129,7 +1129,6 @@ exp_delclient(struct nfsctl_client *ncp)
          */
         if (dom) {
                 err = auth_unix_forget_old(dom);
-                dom->h.expiry_time = get_seconds();
                 auth_domain_put(dom);
         }
 
diff --git a/include/linux/sunrpc/svcauth.h b/include/linux/sunrpc/svcauth.h
index c119ce7cbd22..2fe2087edd66 100644
--- a/include/linux/sunrpc/svcauth.h
+++ b/include/linux/sunrpc/svcauth.h
@@ -45,9 +45,10 @@ struct svc_rqst;		/* forward decl */
  * of ip addresses to the given client.
  */
 struct auth_domain {
-        struct  cache_head      h;
+        struct kref             ref;
+        struct hlist_node       hash;
         char                    *name;
-        int                     flavour;
+        struct auth_ops         *flavour;
 };
 
 /*
@@ -86,6 +87,9 @@ struct auth_domain {
  *
  * domain_release()
  *   This call releases a domain.
+ * set_client()
+ *   Givens a pending request (struct svc_rqst), finds and assigns
+ *   an appropriate 'auth_domain' as the client.
  */
 struct auth_ops {
         char *  name;
@@ -117,7 +121,7 @@ extern void	svc_auth_unregister(rpc_authflavor_t flavor);
 extern struct auth_domain *unix_domain_find(char *name);
 extern void auth_domain_put(struct auth_domain *item);
 extern int auth_unix_add_addr(struct in_addr addr, struct auth_domain *dom);
-extern struct auth_domain *auth_domain_lookup(struct auth_domain *item, int set);
+extern struct auth_domain *auth_domain_lookup(char *name, struct auth_domain *new);
 extern struct auth_domain *auth_domain_find(char *name);
 extern struct auth_domain *auth_unix_lookup(struct in_addr addr);
 extern int auth_unix_forget_old(struct auth_domain *dom);
@@ -160,8 +164,6 @@ static inline unsigned long hash_mem(char *buf, int length, int bits)
         return hash >> (BITS_PER_LONG - bits);
 }
 
-extern struct cache_detail auth_domain_cache, ip_map_cache;
-
 #endif /* __KERNEL__ */
 
 #endif /* _LINUX_SUNRPC_SVCAUTH_H_ */
diff --git a/net/sunrpc/auth_gss/svcauth_gss.c b/net/sunrpc/auth_gss/svcauth_gss.c
index 23632d84d8d7..6b073c2e6930 100644
--- a/net/sunrpc/auth_gss/svcauth_gss.c
+++ b/net/sunrpc/auth_gss/svcauth_gss.c
@@ -645,6 +645,8 @@ find_gss_auth_domain(struct gss_ctx *ctx, u32 svc)
         return auth_domain_find(name);
 }
 
+static struct auth_ops svcauthops_gss;
+
 int
 svcauth_gss_register_pseudoflavor(u32 pseudoflavor, char * name)
 {
@@ -655,20 +657,18 @@ svcauth_gss_register_pseudoflavor(u32 pseudoflavor, char * name)
         new = kmalloc(sizeof(*new), GFP_KERNEL);
         if (!new)
                 goto out;
-        cache_init(&new->h.h);
+        kref_init(&new->h.ref);
         new->h.name = kmalloc(strlen(name) + 1, GFP_KERNEL);
         if (!new->h.name)
                 goto out_free_dom;
         strcpy(new->h.name, name);
-        new->h.flavour = RPC_AUTH_GSS;
+        new->h.flavour = &svcauthops_gss;
         new->pseudoflavor = pseudoflavor;
-        new->h.h.expiry_time = NEVER;
 
-        test = auth_domain_lookup(&new->h, 1);
-        if (test == &new->h) {
-                BUG_ON(atomic_dec_and_test(&new->h.h.refcnt));
-        } else { /* XXX Duplicate registration? */
+        test = auth_domain_lookup(name, &new->h);
+        if (test != &new->h) { /* XXX Duplicate registration? */
                 auth_domain_put(&new->h);
+                /* dangling ref-count... */
                 goto out;
         }
         return 0;
diff --git a/net/sunrpc/sunrpc_syms.c b/net/sunrpc/sunrpc_syms.c
index 9f7373203592..40401196e7de 100644
--- a/net/sunrpc/sunrpc_syms.c
+++ b/net/sunrpc/sunrpc_syms.c
@@ -142,6 +142,7 @@ EXPORT_SYMBOL(nlm_debug);
 
 extern int register_rpc_pipefs(void);
 extern void unregister_rpc_pipefs(void);
+extern struct cache_detail ip_map_cache;
 
 static int __init
 init_sunrpc(void)
@@ -158,7 +159,6 @@ init_sunrpc(void)
 #ifdef CONFIG_PROC_FS
         rpc_proc_init();
 #endif
-        cache_register(&auth_domain_cache);
         cache_register(&ip_map_cache);
 out:
         return err;
@@ -169,8 +169,6 @@ cleanup_sunrpc(void)
 {
         unregister_rpc_pipefs();
         rpc_destroy_mempool();
-        if (cache_unregister(&auth_domain_cache))
-                printk(KERN_ERR "sunrpc: failed to unregister auth_domain cache\n");
         if (cache_unregister(&ip_map_cache))
                 printk(KERN_ERR "sunrpc: failed to unregister ip_map cache\n");
 #ifdef RPC_DEBUG
diff --git a/net/sunrpc/svcauth.c b/net/sunrpc/svcauth.c
index dda4f0c63511..5b28c6176806 100644
--- a/net/sunrpc/svcauth.c
+++ b/net/sunrpc/svcauth.c
@@ -106,112 +106,56 @@ svc_auth_unregister(rpc_authflavor_t flavor)
 EXPORT_SYMBOL(svc_auth_unregister);
 
 /**************************************************
- * cache for domain name to auth_domain
- * Entries are only added by flavours which will normally
- * have a structure that 'inherits' from auth_domain.
- * e.g. when an IP -> domainname is given to  auth_unix,
- * and the domain name doesn't exist, it will create a
- * auth_unix_domain and add it to this hash table.
+ * 'auth_domains' are stored in a hash table indexed by name.
+ * When the last reference to an 'auth_domain' is dropped,
+ * the object is unhashed and freed.
+ * If auth_domain_lookup fails to find an entry, it will return
+ * it's second argument 'new'.  If this is non-null, it will
+ * have been atomically linked into the table.