rhashtable: Add parent argument to mutex_is_held

Currently mutex_is_held can only test locks in the that are global
since it takes no arguments.  This prevents rhashtable from being
used in places where locks are lock, e.g., per-namespace locks.

This patch adds a parent field to mutex_is_held and rhashtable_params
so that local locks can be used (and tested).

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/linux/rhashtable.h

@@ -66,7 +66,8 @@ struct rhashtable_params {
 	bool			(*shrink_decision)(const struct rhashtable *ht,
 						   size_t new_size);
 #ifdef CONFIG_PROVE_LOCKING
-	int			(*mutex_is_held)(void);
+	int			(*mutex_is_held)(void *parent);
+	void			*parent;
 #endif
 };
 

lib/rhashtable.c

@@ -32,7 +32,7 @@
 #ifdef CONFIG_PROVE_LOCKING
 int lockdep_rht_mutex_is_held(const struct rhashtable *ht)
 {
-	return ht->p.mutex_is_held();
+	return ht->p.mutex_is_held(ht->p.parent);
 }
 EXPORT_SYMBOL_GPL(lockdep_rht_mutex_is_held);
 #endif
@@ -618,7 +618,7 @@ EXPORT_SYMBOL_GPL(rhashtable_destroy);
 #define TEST_NEXPANDS	4
 
 #ifdef CONFIG_PROVE_LOCKING
-static int test_mutex_is_held(void)
+static int test_mutex_is_held(void *parent)
 {
 	return 1;
 }

net/netfilter/nft_hash.c

@@ -154,7 +154,7 @@ static unsigned int nft_hash_privsize(const struct nlattr * const nla[])
 }
 
 #ifdef CONFIG_PROVE_LOCKING
-static int lockdep_nfnl_lock_is_held(void)
+static int lockdep_nfnl_lock_is_held(void *parent)
 {
 	return lockdep_nfnl_is_held(NFNL_SUBSYS_NFTABLES);
 }

net/netlink/af_netlink.c

@@ -115,7 +115,7 @@ DEFINE_MUTEX(nl_sk_hash_lock);
 EXPORT_SYMBOL_GPL(nl_sk_hash_lock);
 
 #ifdef CONFIG_PROVE_LOCKING
-static int lockdep_nl_sk_hash_is_held(void)
+static int lockdep_nl_sk_hash_is_held(void *parent)
 {
 	if (debug_locks)
 		return lockdep_is_held(&nl_sk_hash_lock) || lockdep_is_held(&nl_table_lock);