@@ -123,15 +123,38 @@ DEFINE_SPINLOCK(unix_table_lock);
EXPORT_SYMBOL_GPL(unix_table_lock);
static atomic_long_t unix_nr_socks;
+/* SMP locking strategy:
+ * hash table is protected with spinlock unix_table_lock
+ * each socket state is protected by separate spin lock.
+ */
-static struct hlist_head *unix_sockets_unbound(void *addr)
+static unsigned int unix_unbound_hash(struct sock *sk)
{
- unsigned long hash = (unsigned long)addr;
+ unsigned long hash = (unsigned long)sk;
hash ^= hash >> 16;
hash ^= hash >> 8;
- hash %= UNIX_HASH_SIZE;
- return &unix_socket_table[UNIX_HASH_SIZE + hash];
+ hash ^= sk->sk_type;
+
+ return UNIX_HASH_SIZE + (hash & (UNIX_HASH_SIZE - 1));
+}
+
+static unsigned int unix_bsd_hash(struct inode *i)
+{
+ return i->i_ino & (UNIX_HASH_SIZE - 1);
+}
+
+static unsigned int unix_abstract_hash(struct sockaddr_un *sunaddr,
+ int addr_len, int type)
+{
+ __wsum csum = csum_partial(sunaddr, addr_len, 0);
+ unsigned int hash;
+
+ hash = (__force unsigned int)csum_fold(csum);
+ hash ^= hash >> 8;
+ hash ^= type;
+
+ return hash & (UNIX_HASH_SIZE - 1);
}
#ifdef CONFIG_SECURITY_NETWORK
@@ -162,20 +185,6 @@ static inline bool unix_secdata_eq(struct scm_cookie *scm, struct sk_buff *skb)
}
#endif /* CONFIG_SECURITY_NETWORK */
-/*
- * SMP locking strategy:
- * hash table is protected with spinlock unix_table_lock
- * each socket state is protected by separate spin lock.
- */
-
-static inline unsigned int unix_hash_fold(__wsum n)
-{
- unsigned int hash = (__force unsigned int)csum_fold(n);
-
- hash ^= hash>>8;
- return hash&(UNIX_HASH_SIZE-1);
-}
-
#define unix_peer(sk) (unix_sk(sk)->peer)
static inline int unix_our_peer(struct sock *sk, struct sock *osk)
@@ -334,11 +343,11 @@ static inline struct sock *unix_find_socket_byname(struct net *net,
static struct sock *unix_find_socket_byinode(struct inode *i)
{
+ unsigned int hash = unix_bsd_hash(i);
struct sock *s;
spin_lock(&unix_table_lock);
- sk_for_each(s,
- &unix_socket_table[i->i_ino & (UNIX_HASH_SIZE - 1)]) {
+ sk_for_each(s, &unix_socket_table[hash]) {
struct dentry *dentry = unix_sk(s)->path.dentry;
if (dentry && d_backing_inode(dentry) == i) {
@@ -899,7 +908,7 @@ static struct sock *unix_create1(struct net *net, struct socket *sock, int kern,
init_waitqueue_head(&u->peer_wait);
init_waitqueue_func_entry(&u->peer_wake, unix_dgram_peer_wake_relay);
memset(&u->scm_stat, 0, sizeof(struct scm_stat));
- unix_insert_socket(unix_sockets_unbound(sk), sk);
+ unix_insert_socket(&unix_socket_table[unix_unbound_hash(sk)], sk);
sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
@@ -1010,11 +1019,11 @@ static struct sock *unix_find_abstract(struct net *net,
struct sockaddr_un *sunaddr,
int addr_len, int type)
{
- unsigned int hash = unix_hash_fold(csum_partial(sunaddr, addr_len, 0));
+ unsigned int hash = unix_abstract_hash(sunaddr, addr_len, type);
struct dentry *dentry;
struct sock *sk;
- sk = unix_find_socket_byname(net, sunaddr, addr_len, type ^ hash);
+ sk = unix_find_socket_byname(net, sunaddr, addr_len, hash);
if (!sk)
return ERR_PTR(-ECONNREFUSED);
@@ -1066,8 +1075,7 @@ static int unix_autobind(struct sock *sk)
retry:
addr->len = sprintf(addr->name->sun_path + 1, "%05x", ordernum) +
offsetof(struct sockaddr_un, sun_path) + 1;
- addr->hash = unix_hash_fold(csum_partial(addr->name, addr->len, 0));
- addr->hash ^= sk->sk_type;
+ addr->hash = unix_abstract_hash(addr->name, addr->len, sk->sk_type);
spin_lock(&unix_table_lock);
ordernum = (ordernum+1)&0xFFFFF;
@@ -1144,7 +1152,7 @@ static int unix_bind_bsd(struct sock *sk, struct sockaddr_un *sunaddr,
goto out_unlock;
addr->hash = UNIX_HASH_SIZE;
- hash = d_backing_inode(dentry)->i_ino & (UNIX_HASH_SIZE - 1);
+ hash = unix_bsd_hash(d_backing_inode(dentry));
spin_lock(&unix_table_lock);
u->path.mnt = mntget(parent.mnt);
u->path.dentry = dget(dentry);
@@ -1187,9 +1195,7 @@ static int unix_bind_abstract(struct sock *sk, struct sockaddr_un *sunaddr,
goto out_mutex;
}
- addr->hash = unix_hash_fold(csum_partial(addr->name, addr->len, 0));
- addr->hash ^= sk->sk_type;
-
+ addr->hash = unix_abstract_hash(addr->name, addr->len, sk->sk_type);
spin_lock(&unix_table_lock);
if (__unix_find_socket_byname(sock_net(sk), addr->name, addr->len,
This patch adds three helper functions that calculate hashes for unbound sockets and bound sockets with BSD/abstract addresses. Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp> --- net/unix/af_unix.c | 64 +++++++++++++++++++++++++--------------------- 1 file changed, 35 insertions(+), 29 deletions(-)