[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>
diff --git a/fs/nfsd/export.c b/fs/nfsd/export.c
index 417ec02..ac09977 100644
--- a/fs/nfsd/export.c
+++ b/fs/nfsd/export.c
@@ -242,7 +242,7 @@
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 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 @@
*/
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 c119ce7..2fe2087 100644
--- a/include/linux/sunrpc/svcauth.h
+++ b/include/linux/sunrpc/svcauth.h
@@ -45,9 +45,10 @@
* 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 @@
*
* 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 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 @@
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 23632d8..6b073c2 100644
--- a/net/sunrpc/auth_gss/svcauth_gss.c
+++ b/net/sunrpc/auth_gss/svcauth_gss.c
@@ -645,6 +645,8 @@
return auth_domain_find(name);
}
+static struct auth_ops svcauthops_gss;
+
int
svcauth_gss_register_pseudoflavor(u32 pseudoflavor, char * name)
{
@@ -655,20 +657,18 @@
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 9f73732..4040119 100644
--- a/net/sunrpc/sunrpc_syms.c
+++ b/net/sunrpc/sunrpc_syms.c
@@ -142,6 +142,7 @@
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 @@
#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 @@
{
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 dda4f0c..5b28c61 100644
--- a/net/sunrpc/svcauth.c
+++ b/net/sunrpc/svcauth.c
@@ -106,112 +106,56 @@
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.
- * If it finds the name does exist, but isn't AUTH_UNIX,
- * it will complain.
+ * '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.
*/
-/*
- * Auth auth_domain cache is somewhat different to other caches,
- * largely because the entries are possibly of different types:
- * each auth flavour has it's own type.
- * One consequence of this that DefineCacheLookup cannot
- * allocate a new structure as it cannot know the size.
- * Notice that the "INIT" code fragment is quite different
- * from other caches. When auth_domain_lookup might be
- * creating a new domain, the new domain is passed in
- * complete and it is used as-is rather than being copied into
- * another structure.
- */
#define DN_HASHBITS 6
#define DN_HASHMAX (1<<DN_HASHBITS)
#define DN_HASHMASK (DN_HASHMAX-1)
-static struct cache_head *auth_domain_table[DN_HASHMAX];
-
-static void auth_domain_drop(struct cache_head *item, struct cache_detail *cd)
-{
- struct auth_domain *dom = container_of(item, struct auth_domain, h);
- if (cache_put(item,cd))
- authtab[dom->flavour]->domain_release(dom);
-}
-
-
-struct cache_detail auth_domain_cache = {
- .owner = THIS_MODULE,
- .hash_size = DN_HASHMAX,
- .hash_table = auth_domain_table,
- .name = "auth.domain",
- .cache_put = auth_domain_drop,
-};
+static struct hlist_head auth_domain_table[DN_HASHMAX];
+static spinlock_t auth_domain_lock = SPIN_LOCK_UNLOCKED;
void auth_domain_put(struct auth_domain *dom)
{
- auth_domain_drop(&dom->h, &auth_domain_cache);
-}
-
-static inline int auth_domain_hash(struct auth_domain *item)
-{
- return hash_str(item->name, DN_HASHBITS);
-}
-static inline int auth_domain_match(struct auth_domain *tmp, struct auth_domain *item)
-{
- return strcmp(tmp->name, item->name) == 0;
+ if (atomic_dec_and_lock(&dom->ref.refcount, &auth_domain_lock)) {
+ hlist_del(&dom->hash);
+ dom->flavour->domain_release(dom);
+ }
}
struct auth_domain *
-auth_domain_lookup(struct auth_domain *item, int set)
+auth_domain_lookup(char *name, struct auth_domain *new)
{
- struct auth_domain *tmp = NULL;
- struct cache_head **hp, **head;
- head = &auth_domain_cache.hash_table[auth_domain_hash(item)];
+ struct auth_domain *hp;
+ struct hlist_head *head;
+ struct hlist_node *np;
- if (set)
- write_lock(&auth_domain_cache.hash_lock);
- else
- read_lock(&auth_domain_cache.hash_lock);
- for (hp=head; *hp != NULL; hp = &tmp->h.next) {
- tmp = container_of(*hp, struct auth_domain, h);
- if (!auth_domain_match(tmp, item))
- continue;
- if (!set) {
- cache_get(&tmp->h);
- goto out_noset;
+ head = &auth_domain_table[hash_str(name, DN_HASHBITS)];
+
+ spin_lock(&auth_domain_lock);
+
+ hlist_for_each_entry(hp, np, head, hash) {
+ if (strcmp(hp->name, name)==0) {
+ kref_get(&hp->ref);
+ spin_unlock(&auth_domain_lock);
+ return hp;
}
- *hp = tmp->h.next;
- tmp->h.next = NULL;
- auth_domain_drop(&tmp->h, &auth_domain_cache);
- goto out_set;
}
- /* Didn't find anything */
- if (!set)
- goto out_nada;
- auth_domain_cache.entries++;
-out_set:
- item->h.next = *head;
- *head = &item->h;
- cache_get(&item->h);
- write_unlock(&auth_domain_cache.hash_lock);
- cache_fresh(&auth_domain_cache, &item->h, item->h.expiry_time);
- cache_get(&item->h);
- return item;
-out_nada:
- tmp = NULL;
-out_noset:
- read_unlock(&auth_domain_cache.hash_lock);
- return tmp;
+ if (new) {
+ hlist_add_head(&new->hash, head);
+ kref_get(&new->ref);
+ }
+ spin_unlock(&auth_domain_lock);
+ return new;
}
struct auth_domain *auth_domain_find(char *name)
{
- struct auth_domain *rv, ad;
-
- ad.name = name;
- rv = auth_domain_lookup(&ad, 0);
- return rv;
+ return auth_domain_lookup(name, NULL);
}
diff --git a/net/sunrpc/svcauth_unix.c b/net/sunrpc/svcauth_unix.c
index 3e6c694..17e8b2a 100644
--- a/net/sunrpc/svcauth_unix.c
+++ b/net/sunrpc/svcauth_unix.c
@@ -27,41 +27,35 @@
/* other stuff later */
};
+extern struct auth_ops svcauth_unix;
+
struct auth_domain *unix_domain_find(char *name)
{
- struct auth_domain *rv, ud;
- struct unix_domain *new;
+ struct auth_domain *rv;
+ struct unix_domain *new = NULL;
- ud.name = name;
-
- rv = auth_domain_lookup(&ud, 0);
+ rv = auth_domain_lookup(name, NULL);
+ while(1) {
+ if (rv != &new->h) {
+ if (new) auth_domain_put(&new->h);
+ return rv;
+ }
+ if (rv && rv->flavour != &svcauth_unix) {
+ auth_domain_put(rv);
+ return NULL;
+ }
+ if (rv)
+ return rv;
- foundit:
- if (rv && rv->flavour != RPC_AUTH_UNIX) {
- auth_domain_put(rv);
- return NULL;
+ new = kmalloc(sizeof(*new), GFP_KERNEL);
+ if (new == NULL)
+ return NULL;
+ kref_init(&new->h.ref);
+ new->h.name = kstrdup(name, GFP_KERNEL);
+ new->h.flavour = &svcauth_unix;
+ new->addr_changes = 0;
+ rv = auth_domain_lookup(name, &new->h);
}
- if (rv)
- return rv;
-
- new = kmalloc(sizeof(*new), GFP_KERNEL);
- if (new == NULL)
- return NULL;
- cache_init(&new->h.h);
- new->h.name = kstrdup(name, GFP_KERNEL);
- new->h.flavour = RPC_AUTH_UNIX;
- new->addr_changes = 0;
- new->h.h.expiry_time = NEVER;
-
- rv = auth_domain_lookup(&new->h, 2);
- if (rv == &new->h) {
- if (atomic_dec_and_test(&new->h.h.refcnt)) BUG();
- } else {
- auth_domain_put(&new->h);
- goto foundit;
- }
-
- return rv;
}
static void svcauth_unix_domain_release(struct auth_domain *dom)
@@ -130,7 +124,7 @@
}
static inline void ip_map_update(struct ip_map *new, struct ip_map *item)
{
- cache_get(&item->m_client->h.h);
+ kref_get(&item->m_client->h.ref);
new->m_client = item->m_client;
new->m_add_change = item->m_add_change;
}
@@ -272,7 +266,7 @@
struct unix_domain *udom;
struct ip_map ip, *ipmp;
- if (dom->flavour != RPC_AUTH_UNIX)
+ if (dom->flavour != &svcauth_unix)
return -EINVAL;
udom = container_of(dom, struct unix_domain, h);
strcpy(ip.m_class, "nfsd");
@@ -295,7 +289,7 @@
{
struct unix_domain *udom;
- if (dom->flavour != RPC_AUTH_UNIX)
+ if (dom->flavour != &svcauth_unix)
return -EINVAL;
udom = container_of(dom, struct unix_domain, h);
udom->addr_changes++;
@@ -323,7 +317,7 @@
rv = NULL;
} else {
rv = &ipm->m_client->h;
- cache_get(&rv->h);
+ kref_get(&rv->ref);
}
ip_map_put(&ipm->h, &ip_map_cache);
return rv;
@@ -332,7 +326,6 @@
void svcauth_unix_purge(void)
{
cache_purge(&ip_map_cache);
- cache_purge(&auth_domain_cache);
}
static int
@@ -361,7 +354,7 @@
return SVC_DENIED;
case 0:
rqstp->rq_client = &ipm->m_client->h;
- cache_get(&rqstp->rq_client->h);
+ kref_get(&rqstp->rq_client->ref);
ip_map_put(&ipm->h, &ip_map_cache);
break;
}