From: Samuel Ortiz <sameo@linux.intel.com>
To: "John W. Linville" <linville@tuxdriver.com>
Cc: Lauro Ramos Venancio <lauro.venancio@openbossa.org>,
Aloisio Almeida Jr <aloisio.almeida@openbossa.org>,
Ilan Elias <ilane@ti.com>,
linux-wireless@vger.kernel.org, linux-nfc@lists.01.org,
Samuel Ortiz <sameo@linux.intel.com>
Subject: [PATCH 25/33] NFC: LLCP late binding
Date: Fri, 6 Jul 2012 22:09:45 +0200 [thread overview]
Message-ID: <1341605393-32056-26-git-send-email-sameo@linux.intel.com> (raw)
In-Reply-To: <1341605393-32056-1-git-send-email-sameo@linux.intel.com>
With the LLCP 16 local SAPs we can potentially quickly run out of source
SAPs for non well known services.
With the so called late binding we will reserve an SAP only when we actually
get a client connection for a local service. The SAP will be released once
the last client is gone, leaving it available to other services.
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
---
net/nfc/llcp/llcp.c | 241 +++++++++++++++++++++++++++++++++++----------------
net/nfc/llcp/llcp.h | 2 +
2 files changed, 166 insertions(+), 77 deletions(-)
diff --git a/net/nfc/llcp/llcp.c b/net/nfc/llcp/llcp.c
index 9ab17ec..6094a20 100644
--- a/net/nfc/llcp/llcp.c
+++ b/net/nfc/llcp/llcp.c
@@ -131,6 +131,44 @@ int nfc_llcp_local_put(struct nfc_llcp_local *local)
return kref_put(&local->ref, local_release);
}
+static struct nfc_llcp_sock *nfc_llcp_sock_get(struct nfc_llcp_local *local,
+ u8 ssap, u8 dsap)
+{
+ 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;
+
+ 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 void nfc_llcp_sock_put(struct nfc_llcp_sock *sock)
+{
+ sock_put(&sock->sk);
+}
+
static void nfc_llcp_timeout_work(struct work_struct *work)
{
struct nfc_llcp_local *local = container_of(work, struct nfc_llcp_local,
@@ -191,6 +229,51 @@ static int nfc_llcp_wks_sap(char *service_name, size_t service_name_len)
return -EINVAL;
}
+static
+struct nfc_llcp_sock *nfc_llcp_sock_from_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, *tmp_sock;
+
+ pr_debug("sn %zd %p\n", sn_len, sn);
+
+ if (sn == NULL || sn_len == 0)
+ return NULL;
+
+ read_lock(&local->sockets.lock);
+
+ llcp_sock = NULL;
+
+ sk_for_each(sk, node, &local->sockets.head) {
+ tmp_sock = nfc_llcp_sock(sk);
+
+ pr_debug("llcp sock %p\n", tmp_sock);
+
+ if (tmp_sock->sk.sk_state != LLCP_LISTEN)
+ continue;
+
+ if (tmp_sock->service_name == NULL ||
+ tmp_sock->service_name_len == 0)
+ continue;
+
+ if (tmp_sock->service_name_len != sn_len)
+ continue;
+
+ if (memcmp(sn, tmp_sock->service_name, sn_len) == 0) {
+ llcp_sock = tmp_sock;
+ break;
+ }
+ }
+
+ read_unlock(&local->sockets.lock);
+
+ pr_debug("Found llcp sock %p\n", llcp_sock);
+
+ return llcp_sock;
+}
+
u8 nfc_llcp_get_sdp_ssap(struct nfc_llcp_local *local,
struct nfc_llcp_sock *sock)
{
@@ -217,22 +300,19 @@ u8 nfc_llcp_get_sdp_ssap(struct nfc_llcp_local *local,
}
/*
- * This is not a well known service,
- * we should try to find a local SDP free spot
+ * Check if there already is a non WKS socket bound
+ * to this service name.
*/
- ssap = find_first_zero_bit(&local->local_sdp, LLCP_SDP_NUM_SAP);
- if (ssap == LLCP_SDP_NUM_SAP) {
+ if (nfc_llcp_sock_from_sn(local, sock->service_name,
+ sock->service_name_len) != NULL) {
mutex_unlock(&local->sdp_lock);
return LLCP_SAP_MAX;
}
- pr_debug("SDP ssap %d\n", LLCP_WKS_NUM_SAP + ssap);
-
- set_bit(ssap, &local->local_sdp);
mutex_unlock(&local->sdp_lock);
- return LLCP_WKS_NUM_SAP + ssap;
+ return LLCP_SDP_UNBOUND;
} else if (sock->ssap != 0 && sock->ssap < LLCP_WKS_NUM_SAP) {
if (!test_bit(sock->ssap, &local->local_wks)) {
@@ -276,8 +356,34 @@ void nfc_llcp_put_ssap(struct nfc_llcp_local *local, u8 ssap)
local_ssap = ssap;
sdp = &local->local_wks;
} else if (ssap < LLCP_LOCAL_NUM_SAP) {
+ atomic_t *client_cnt;
+
local_ssap = ssap - LLCP_WKS_NUM_SAP;
sdp = &local->local_sdp;
+ client_cnt = &local->local_sdp_cnt[local_ssap];
+
+ pr_debug("%d clients\n", atomic_read(client_cnt));
+
+ mutex_lock(&local->sdp_lock);
+
+ if (atomic_dec_and_test(client_cnt)) {
+ struct nfc_llcp_sock *l_sock;
+
+ pr_debug("No more clients for SAP %d\n", ssap);
+
+ clear_bit(local_ssap, sdp);
+
+ /* Find the listening sock and set it back to UNBOUND */
+ l_sock = nfc_llcp_sock_get(local, ssap, LLCP_SAP_SDP);
+ if (l_sock) {
+ l_sock->ssap = LLCP_SDP_UNBOUND;
+ nfc_llcp_sock_put(l_sock);
+ }
+ }
+
+ mutex_unlock(&local->sdp_lock);
+
+ return;
} else if (ssap < LLCP_MAX_SAP) {
local_ssap = ssap - LLCP_LOCAL_NUM_SAP;
sdp = &local->local_sap;
@@ -292,6 +398,28 @@ void nfc_llcp_put_ssap(struct nfc_llcp_local *local, u8 ssap)
mutex_unlock(&local->sdp_lock);
}
+static u8 nfc_llcp_reserve_sdp_ssap(struct nfc_llcp_local *local)
+{
+ u8 ssap;
+
+ mutex_lock(&local->sdp_lock);
+
+ ssap = find_first_zero_bit(&local->local_sdp, LLCP_SDP_NUM_SAP);
+ if (ssap == LLCP_SDP_NUM_SAP) {
+ mutex_unlock(&local->sdp_lock);
+
+ return LLCP_SAP_MAX;
+ }
+
+ pr_debug("SDP ssap %d\n", LLCP_WKS_NUM_SAP + ssap);
+
+ set_bit(ssap, &local->local_sdp);
+
+ mutex_unlock(&local->sdp_lock);
+
+ return LLCP_WKS_NUM_SAP + ssap;
+}
+
static int nfc_llcp_build_gb(struct nfc_llcp_local *local)
{
u8 *gb_cur, *version_tlv, version, version_length;
@@ -493,74 +621,12 @@ out:
return llcp_sock;
}
-static struct nfc_llcp_sock *nfc_llcp_sock_get(struct nfc_llcp_local *local,
- u8 ssap, u8 dsap)
-{
- 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;
-
- 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;
- }
-
- read_unlock(&local->sockets.lock);
+ llcp_sock = nfc_llcp_sock_from_sn(local, sn, sn_len);
if (llcp_sock == NULL)
return NULL;
@@ -570,11 +636,6 @@ static struct nfc_llcp_sock *nfc_llcp_sock_get_sn(struct nfc_llcp_local *local,
return llcp_sock;
}
-static void nfc_llcp_sock_put(struct nfc_llcp_sock *sock)
-{
- sock_put(&sock->sk);
-}
-
static u8 *nfc_llcp_connect_sn(struct sk_buff *skb, size_t *sn_len)
{
u8 *tlv = &skb->data[2], type, length;
@@ -646,6 +707,21 @@ static void nfc_llcp_recv_connect(struct nfc_llcp_local *local,
goto fail;
}
+ if (sock->ssap == LLCP_SDP_UNBOUND) {
+ u8 ssap = nfc_llcp_reserve_sdp_ssap(local);
+
+ pr_debug("First client, reserving %d\n", ssap);
+
+ if (ssap == LLCP_SAP_MAX) {
+ reason = LLCP_DM_REJ;
+ release_sock(&sock->sk);
+ sock_put(&sock->sk);
+ goto fail;
+ }
+
+ sock->ssap = ssap;
+ }
+
new_sk = nfc_llcp_sock_alloc(NULL, parent->sk_type, GFP_ATOMIC);
if (new_sk == NULL) {
reason = LLCP_DM_REJ;
@@ -659,10 +735,21 @@ static void nfc_llcp_recv_connect(struct nfc_llcp_local *local,
new_sock->local = nfc_llcp_local_get(local);
new_sock->miu = local->remote_miu;
new_sock->nfc_protocol = sock->nfc_protocol;
- new_sock->ssap = sock->ssap;
new_sock->dsap = ssap;
new_sock->target_idx = local->target_idx;
new_sock->parent = parent;
+ new_sock->ssap = sock->ssap;
+ if (sock->ssap < LLCP_LOCAL_NUM_SAP && sock->ssap >= LLCP_WKS_NUM_SAP) {
+ atomic_t *client_count;
+
+ pr_debug("reserved_ssap %d for %p\n", sock->ssap, new_sock);
+
+ client_count =
+ &local->local_sdp_cnt[sock->ssap - LLCP_WKS_NUM_SAP];
+
+ atomic_inc(client_count);
+ new_sock->reserved_ssap = sock->ssap;
+ }
nfc_llcp_parse_connection_tlv(new_sock, &skb->data[LLCP_HEADER_SIZE],
skb->len - LLCP_HEADER_SIZE);
diff --git a/net/nfc/llcp/llcp.h b/net/nfc/llcp/llcp.h
index 374cc47..83b8bba 100644
--- a/net/nfc/llcp/llcp.h
+++ b/net/nfc/llcp/llcp.h
@@ -37,6 +37,7 @@ enum llcp_state {
#define LLCP_LOCAL_NUM_SAP 32
#define LLCP_LOCAL_SAP_OFFSET (LLCP_WKS_NUM_SAP + LLCP_SDP_NUM_SAP)
#define LLCP_MAX_SAP (LLCP_WKS_NUM_SAP + LLCP_SDP_NUM_SAP + LLCP_LOCAL_NUM_SAP)
+#define LLCP_SDP_UNBOUND (LLCP_MAX_SAP + 1)
struct nfc_llcp_sock;
@@ -69,6 +70,7 @@ struct nfc_llcp_local {
unsigned long local_wks; /* Well known services */
unsigned long local_sdp; /* Local services */
unsigned long local_sap; /* Local SAPs, not available for discovery */
+ atomic_t local_sdp_cnt[LLCP_SDP_NUM_SAP];
/* local */
u8 gb[NFC_MAX_GT_LEN];
--
1.7.10
next prev parent reply other threads:[~2012-07-06 20:00 UTC|newest]
Thread overview: 34+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-07-06 20:09 [PATCH 00/33] NFC updates for 3.6 Samuel Ortiz
2012-07-06 20:09 ` [PATCH 01/33] NFC: Prepare asynchronous error management for driver and shdlc Samuel Ortiz
2012-07-06 20:09 ` [PATCH 02/33] NFC: Removed addressed shdlc TODOs Samuel Ortiz
2012-07-06 20:09 ` [PATCH 03/33] NFC: Handle SHDLC RSET frames from an SHDLC connected chip Samuel Ortiz
2012-07-06 20:09 ` [PATCH 04/33] NFC: Remove an impossible HCI error case Samuel Ortiz
2012-07-06 20:09 ` [PATCH 05/33] NFC: Implement HCP reaggregation allocation " Samuel Ortiz
2012-07-06 20:09 ` [PATCH 06/33] NFC: Changed HCI cmd execution completion result to std linux errno Samuel Ortiz
2012-07-06 20:09 ` [PATCH 07/33] NFC: Driver failure API Samuel Ortiz
2012-07-06 20:09 ` [PATCH 08/33] NFC: Factorize HCI cmd completion Samuel Ortiz
2012-07-06 20:09 ` [PATCH 09/33] NFC: Implement HCI driver or internal error management Samuel Ortiz
2012-07-06 20:09 ` [PATCH 10/33] NFC: Core must test the device polling state inside the device lock Samuel Ortiz
2012-07-06 20:09 ` [PATCH 11/33] NFC: nfc_targets_found() should accept zero target found Samuel Ortiz
2012-07-06 20:09 ` [PATCH 12/33] NFC: nfc_driver_failure() implementation Samuel Ortiz
2012-07-06 20:09 ` [PATCH 13/33] NFC: Error management documentation Samuel Ortiz
2012-07-06 20:09 ` [PATCH 14/33] NFC: update PN544 HCI driver state when opened/closed Samuel Ortiz
2012-07-06 20:09 ` [PATCH 15/33] NFC: Allow HCI driver to pre-open pipes to some gates Samuel Ortiz
2012-07-06 20:09 ` [PATCH 16/33] NFC: Add modules alias for NFC sockets Samuel Ortiz
2012-07-06 20:09 ` [PATCH 17/33] NFC: Add netlink module alias for NFC Samuel Ortiz
2012-07-06 20:09 ` [PATCH 18/33] NFC: Update LLCP socket target index when getting a connection Samuel Ortiz
2012-07-06 20:09 ` [PATCH 19/33] NFC: Fix LLCP getname socket op Samuel Ortiz
2012-07-06 20:09 ` [PATCH 20/33] NFC: Build LLCP general bytes upon request Samuel Ortiz
2012-07-06 20:09 ` [PATCH 21/33] NFC: Close listening LLCP sockets when the device is gone Samuel Ortiz
2012-07-06 20:09 ` [PATCH 22/33] NFC: Release LLCP SAP when the owner is released Samuel Ortiz
2012-07-06 20:09 ` [PATCH 23/33] NFC: Forbid LLCP service name reusing Samuel Ortiz
2012-07-06 20:09 ` [PATCH 24/33] NFC: Forbid SSAP binding to a not well known LLCP service Samuel Ortiz
2012-07-06 20:09 ` Samuel Ortiz [this message]
2012-07-06 20:09 ` [PATCH 26/33] NFC: Handle LLCP Disconnected Mode frames Samuel Ortiz
2012-07-06 20:09 ` [PATCH 27/33] NFC: Remove warning from nfc_llcp_local_put Samuel Ortiz
2012-07-06 20:09 ` [PATCH 28/33] NFC: Do not return EBUSY when stopping a poll that's already stopped Samuel Ortiz
2012-07-06 20:09 ` [PATCH 29/33] NFC: Dereference LLCP bind socket address after checking for it to be NULL Samuel Ortiz
2012-07-06 20:09 ` [PATCH 30/33] NFC: Add initial Sony RC-S360 support to pn533 Samuel Ortiz
2012-07-06 20:09 ` [PATCH 31/33] NFC: Use communicate thru only for PaSoRi when trying to read Felica tags Samuel Ortiz
2012-07-06 20:09 ` [PATCH 32/33] NFC: Add ISO 14443 type B protocol Samuel Ortiz
2012-07-06 20:09 ` [PATCH 33/33] NFC: Check for llcp_sock and its device from llcp_sock_getname Samuel Ortiz
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