NFC: Socket linked list
Simplify the LLCP sockets structure by putting all the connected ones
into a single linked list.
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
diff --git a/net/nfc/llcp/llcp.c b/net/nfc/llcp/llcp.c
index 0f6dd3a..262aa82 100644
--- a/net/nfc/llcp/llcp.c
+++ b/net/nfc/llcp/llcp.c
@@ -31,45 +31,41 @@
static struct list_head llcp_devices;
+void nfc_llcp_sock_link(struct llcp_sock_list *l, struct sock *sk)
+{
+ write_lock(&l->lock);
+ sk_add_node(sk, &l->head);
+ write_unlock(&l->lock);
+}
+
+void nfc_llcp_sock_unlink(struct llcp_sock_list *l, struct sock *sk)
+{
+ write_lock(&l->lock);
+ sk_del_node_init(sk);
+ write_unlock(&l->lock);
+}
+
static void nfc_llcp_socket_release(struct nfc_llcp_local *local)
{
- struct nfc_llcp_sock *parent, *s, *n;
- struct sock *sk, *parent_sk;
- int i;
+ struct sock *sk;
+ struct hlist_node *node, *tmp;
+ struct nfc_llcp_sock *llcp_sock;
- mutex_lock(&local->socket_lock);
+ write_lock(&local->sockets.lock);
- for (i = 0; i < LLCP_MAX_SAP; i++) {
- parent = local->sockets[i];
- if (parent == NULL)
- continue;
+ sk_for_each_safe(sk, node, tmp, &local->sockets.head) {
+ llcp_sock = nfc_llcp_sock(sk);
- /* Release all child sockets */
- list_for_each_entry_safe(s, n, &parent->list, list) {
- list_del_init(&s->list);
- sk = &s->sk;
+ lock_sock(sk);
- lock_sock(sk);
+ if (sk->sk_state == LLCP_CONNECTED)
+ nfc_put_device(llcp_sock->dev);
- if (sk->sk_state == LLCP_CONNECTED)
- nfc_put_device(s->dev);
-
- sk->sk_state = LLCP_CLOSED;
-
- release_sock(sk);
-
- sock_orphan(sk);
- }
-
- parent_sk = &parent->sk;
-
- lock_sock(parent_sk);
-
- if (parent_sk->sk_state == LLCP_LISTEN) {
+ if (sk->sk_state == LLCP_LISTEN) {
struct nfc_llcp_sock *lsk, *n;
struct sock *accept_sk;
- list_for_each_entry_safe(lsk, n, &parent->accept_queue,
+ list_for_each_entry_safe(lsk, n, &llcp_sock->accept_queue,
accept_queue) {
accept_sk = &lsk->sk;
lock_sock(accept_sk);
@@ -84,17 +80,16 @@
}
}
- if (parent_sk->sk_state == LLCP_CONNECTED)
- nfc_put_device(parent->dev);
+ sk->sk_state = LLCP_CLOSED;
- parent_sk->sk_state = LLCP_CLOSED;
+ release_sock(sk);
- release_sock(parent_sk);
+ sock_orphan(sk);
- sock_orphan(parent_sk);
+ sk_del_node_init(sk);
}
- mutex_unlock(&local->socket_lock);
+ write_unlock(&local->sockets.lock);
}
struct nfc_llcp_local *nfc_llcp_local_get(struct nfc_llcp_local *local)
@@ -122,6 +117,11 @@
int nfc_llcp_local_put(struct nfc_llcp_local *local)
{
+ WARN_ON(local == NULL);
+
+ if (local == NULL)
+ return 0;
+
return kref_put(&local->ref, local_release);
}
@@ -465,46 +465,107 @@
sock->recv_ack_n = (sock->recv_n - 1) % 16;
}
+static struct nfc_llcp_sock *nfc_llcp_connecting_sock_get(struct nfc_llcp_local *local,
+ u8 ssap)
+{
+ struct sock *sk;
+ struct nfc_llcp_sock *llcp_sock;
+ struct hlist_node *node;
+
+ read_lock(&local->connecting_sockets.lock);
+
+ sk_for_each(sk, node, &local->connecting_sockets.head) {
+ llcp_sock = nfc_llcp_sock(sk);
+
+ if (llcp_sock->ssap == ssap)
+ goto out;
+ }
+
+ llcp_sock = NULL;
+
+out:
+ read_unlock(&local->connecting_sockets.lock);
+
+ sock_hold(&llcp_sock->sk);
+
+ return llcp_sock;
+}
+
static struct nfc_llcp_sock *nfc_llcp_sock_get(struct nfc_llcp_local *local,
u8 ssap, u8 dsap)
{
- struct nfc_llcp_sock *sock, *llcp_sock, *n;
+ struct sock *sk;
+ struct hlist_node *node;
+ struct nfc_llcp_sock *llcp_sock;
pr_debug("ssap dsap %d %d\n", ssap, dsap);
if (ssap == 0 && dsap == 0)
return NULL;
- mutex_lock(&local->socket_lock);
- sock = local->sockets[ssap];
- if (sock == NULL) {
- mutex_unlock(&local->socket_lock);
+ read_lock(&local->sockets.lock);
+
+ llcp_sock = NULL;
+
+ sk_for_each(sk, node, &local->sockets.head) {
+ llcp_sock = nfc_llcp_sock(sk);
+
+ if (llcp_sock->ssap == ssap &&
+ llcp_sock->dsap == dsap)
+ break;
+ }
+
+ read_unlock(&local->sockets.lock);
+
+ if (llcp_sock == NULL)
return NULL;
+
+ sock_hold(&llcp_sock->sk);
+
+ return llcp_sock;
+}
+
+static struct nfc_llcp_sock *nfc_llcp_sock_get_sn(struct nfc_llcp_local *local,
+ u8 *sn, size_t sn_len)
+{
+ struct sock *sk;
+ struct hlist_node *node;
+ struct nfc_llcp_sock *llcp_sock;
+
+ pr_debug("sn %zd\n", sn_len);
+
+ if (sn == NULL || sn_len == 0)
+ return NULL;
+
+ read_lock(&local->sockets.lock);
+
+ llcp_sock = NULL;
+
+ sk_for_each(sk, node, &local->sockets.head) {
+ llcp_sock = nfc_llcp_sock(sk);
+
+ if (llcp_sock->sk.sk_state != LLCP_LISTEN)
+ continue;
+
+ if (llcp_sock->service_name == NULL ||
+ llcp_sock->service_name_len == 0)
+ continue;
+
+ if (llcp_sock->service_name_len != sn_len)
+ continue;
+
+ if (memcmp(sn, llcp_sock->service_name, sn_len) == 0)
+ break;
}
- pr_debug("root dsap %d (%d)\n", sock->dsap, dsap);
+ read_unlock(&local->sockets.lock);
- if (sock->dsap == dsap) {
- sock_hold(&sock->sk);
- mutex_unlock(&local->socket_lock);
- return sock;
- }
+ if (llcp_sock == NULL)
+ return NULL;
- list_for_each_entry_safe(llcp_sock, n, &sock->list, list) {
- pr_debug("llcp_sock %p sk %p dsap %d\n", llcp_sock,
- &llcp_sock->sk, llcp_sock->dsap);
- if (llcp_sock->dsap == dsap) {
- sock_hold(&llcp_sock->sk);
- mutex_unlock(&local->socket_lock);
- return llcp_sock;
- }
- }
+ sock_hold(&llcp_sock->sk);
- pr_err("Could not find socket for %d %d\n", ssap, dsap);
-
- mutex_unlock(&local->socket_lock);
-
- return NULL;
+ return llcp_sock;
}
static void nfc_llcp_sock_put(struct nfc_llcp_sock *sock)
@@ -540,7 +601,7 @@
{
struct sock *new_sk, *parent;
struct nfc_llcp_sock *sock, *new_sock;
- u8 dsap, ssap, bound_sap, reason;
+ u8 dsap, ssap, reason;
dsap = nfc_llcp_dsap(skb);
ssap = nfc_llcp_ssap(skb);
@@ -551,24 +612,11 @@
skb->len - LLCP_HEADER_SIZE);
if (dsap != LLCP_SAP_SDP) {
- bound_sap = dsap;
-
- mutex_lock(&local->socket_lock);
- sock = local->sockets[dsap];
- if (sock == NULL) {
- mutex_unlock(&local->socket_lock);
+ sock = nfc_llcp_sock_get(local, dsap, LLCP_SAP_SDP);
+ if (sock == NULL || sock->sk.sk_state != LLCP_LISTEN) {
reason = LLCP_DM_NOBOUND;
goto fail;
}
-
- sock_hold(&sock->sk);
- mutex_unlock(&local->socket_lock);
-
- lock_sock(&sock->sk);
-
- if (sock->dsap == LLCP_SAP_SDP &&
- sock->sk.sk_state == LLCP_LISTEN)
- goto enqueue;
} else {
u8 *sn;
size_t sn_len;
@@ -581,40 +629,15 @@
pr_debug("Service name length %zu\n", sn_len);
- mutex_lock(&local->socket_lock);
- for (bound_sap = 0; bound_sap < LLCP_LOCAL_SAP_OFFSET;
- bound_sap++) {
- sock = local->sockets[bound_sap];
- if (sock == NULL)
- continue;
-
- if (sock->service_name == NULL ||
- sock->service_name_len == 0)
- continue;
-
- if (sock->service_name_len != sn_len)
- continue;
-
- if (sock->dsap == LLCP_SAP_SDP &&
- sock->sk.sk_state == LLCP_LISTEN &&
- !memcmp(sn, sock->service_name, sn_len)) {
- pr_debug("Found service name at SAP %d\n",
- bound_sap);
- sock_hold(&sock->sk);
- mutex_unlock(&local->socket_lock);
-
- lock_sock(&sock->sk);
-
- goto enqueue;
- }
+ sock = nfc_llcp_sock_get_sn(local, sn, sn_len);
+ if (sock == NULL) {
+ reason = LLCP_DM_NOBOUND;
+ goto fail;
}
- mutex_unlock(&local->socket_lock);
}
- reason = LLCP_DM_NOBOUND;
- goto fail;
+ lock_sock(&sock->sk);
-enqueue:
parent = &sock->sk;
if (sk_acceptq_is_full(parent)) {
@@ -636,13 +659,13 @@
new_sock->dev = local->dev;
new_sock->local = nfc_llcp_local_get(local);
new_sock->nfc_protocol = sock->nfc_protocol;
- new_sock->ssap = bound_sap;
+ new_sock->ssap = sock->ssap;
new_sock->dsap = ssap;
new_sock->parent = parent;
pr_debug("new sock %p sk %p\n", new_sock, &new_sock->sk);
- list_add_tail(&new_sock->list, &sock->list);
+ nfc_llcp_sock_link(&local->sockets, new_sk);
nfc_llcp_accept_enqueue(&sock->sk, new_sk);
@@ -813,11 +836,7 @@
dsap = nfc_llcp_dsap(skb);
ssap = nfc_llcp_ssap(skb);
- llcp_sock = nfc_llcp_sock_get(local, dsap, ssap);
-
- if (llcp_sock == NULL)
- llcp_sock = nfc_llcp_sock_get(local, dsap, LLCP_SAP_SDP);
-
+ llcp_sock = nfc_llcp_connecting_sock_get(local, dsap);
if (llcp_sock == NULL) {
pr_err("Invalid CC\n");
nfc_llcp_send_dm(local, dsap, ssap, LLCP_DM_NOCONN);
@@ -825,9 +844,13 @@
return;
}
- llcp_sock->dsap = ssap;
sk = &llcp_sock->sk;
+ /* Unlink from connecting and link to the client array */
+ nfc_llcp_sock_unlink(&local->connecting_sockets, sk);
+ nfc_llcp_sock_link(&local->sockets, sk);
+ llcp_sock->dsap = ssap;
+
nfc_llcp_parse_tlv(local, &skb->data[LLCP_HEADER_SIZE],
skb->len - LLCP_HEADER_SIZE);
@@ -967,7 +990,6 @@
INIT_LIST_HEAD(&local->list);
kref_init(&local->ref);
mutex_init(&local->sdp_lock);
- mutex_init(&local->socket_lock);
init_timer(&local->link_timer);
local->link_timer.data = (unsigned long) local;
local->link_timer.function = nfc_llcp_symm_timer;
@@ -1007,6 +1029,9 @@
goto err_rx_wq;
}
+ local->sockets.lock = __RW_LOCK_UNLOCKED(local->sockets.lock);
+ local->connecting_sockets.lock = __RW_LOCK_UNLOCKED(local->connecting_sockets.lock);
+
nfc_llcp_build_gb(local);
local->remote_miu = LLCP_DEFAULT_MIU;