From 844579603889ef1ab1fdbf2223579d6842e62bfe Mon Sep 17 00:00:00 2001 From: Samuel Ortiz Date: Wed, 30 May 2012 17:48:29 +0200 Subject: [PATCH] NFC: Requeue lost LLCP frames When receiving an I or RR frame telling us that some of the pending queues were not received, we should requeue them before the currently pending ones. Signed-off-by: Samuel Ortiz --- net/nfc/llcp/llcp.c | 86 +++++++++++++++++++++++++++++---------------- 1 file changed, 55 insertions(+), 31 deletions(-) diff --git a/net/nfc/llcp/llcp.c b/net/nfc/llcp/llcp.c index b694313c2be5..0fc60da6a0a1 100644 --- a/net/nfc/llcp/llcp.c +++ b/net/nfc/llcp/llcp.c @@ -411,28 +411,6 @@ int nfc_llcp_set_remote_gb(struct nfc_dev *dev, u8 *gb, u8 gb_len) local->remote_gb_len - 3); } -static void nfc_llcp_tx_work(struct work_struct *work) -{ - struct nfc_llcp_local *local = container_of(work, struct nfc_llcp_local, - tx_work); - struct sk_buff *skb; - - skb = skb_dequeue(&local->tx_queue); - if (skb != NULL) { - pr_debug("Sending pending skb\n"); - print_hex_dump(KERN_DEBUG, "LLCP Tx: ", DUMP_PREFIX_OFFSET, - 16, 1, skb->data, skb->len, true); - - nfc_data_exchange(local->dev, local->target_idx, - skb, nfc_llcp_recv, local); - } else { - nfc_llcp_send_symm(local->dev); - } - - mod_timer(&local->link_timer, - jiffies + msecs_to_jiffies(local->remote_lto)); -} - static u8 nfc_llcp_dsap(struct sk_buff *pdu) { return (pdu->data[0] & 0xfc) >> 2; @@ -465,6 +443,45 @@ static void nfc_llcp_set_nrns(struct nfc_llcp_sock *sock, struct sk_buff *pdu) sock->recv_ack_n = (sock->recv_n - 1) % 16; } +static void nfc_llcp_tx_work(struct work_struct *work) +{ + struct nfc_llcp_local *local = container_of(work, struct nfc_llcp_local, + tx_work); + struct sk_buff *skb; + struct sock *sk; + struct nfc_llcp_sock *llcp_sock; + + skb = skb_dequeue(&local->tx_queue); + if (skb != NULL) { + sk = skb->sk; + llcp_sock = nfc_llcp_sock(sk); + if (llcp_sock != NULL) { + int ret; + + pr_debug("Sending pending skb\n"); + print_hex_dump(KERN_DEBUG, "LLCP Tx: ", + DUMP_PREFIX_OFFSET, 16, 1, + skb->data, skb->len, true); + + ret = nfc_data_exchange(local->dev, local->target_idx, + skb, nfc_llcp_recv, local); + + if (!ret && nfc_llcp_ptype(skb) == LLCP_PDU_I) { + skb = skb_get(skb); + skb_queue_tail(&llcp_sock->tx_pending_queue, + skb); + } + } else { + nfc_llcp_send_symm(local->dev); + } + } else { + nfc_llcp_send_symm(local->dev); + } + + mod_timer(&local->link_timer, + jiffies + msecs_to_jiffies(2 * local->remote_lto)); +} + static struct nfc_llcp_sock *nfc_llcp_connecting_sock_get(struct nfc_llcp_local *local, u8 ssap) { @@ -705,7 +722,7 @@ int nfc_llcp_queue_i_frames(struct nfc_llcp_sock *sock) /* Try to queue some I frames for transmission */ while (sock->remote_ready && skb_queue_len(&sock->tx_pending_queue) < sock->rw) { - struct sk_buff *pdu, *pending_pdu; + struct sk_buff *pdu; pdu = skb_dequeue(&sock->tx_queue); if (pdu == NULL) @@ -714,10 +731,7 @@ int nfc_llcp_queue_i_frames(struct nfc_llcp_sock *sock) /* Update N(S)/N(R) */ nfc_llcp_set_nrns(sock, pdu); - pending_pdu = skb_clone(pdu, GFP_KERNEL); - skb_queue_tail(&local->tx_queue, pdu); - skb_queue_tail(&sock->tx_pending_queue, pending_pdu); nr_frames++; } @@ -774,11 +788,21 @@ static void nfc_llcp_recv_hdlc(struct nfc_llcp_local *local, llcp_sock->send_ack_n = nr; - skb_queue_walk_safe(&llcp_sock->tx_pending_queue, s, tmp) - if (nfc_llcp_ns(s) <= nr) { - skb_unlink(s, &llcp_sock->tx_pending_queue); - kfree_skb(s); - } + /* Remove and free all skbs until ns == nr */ + skb_queue_walk_safe(&llcp_sock->tx_pending_queue, s, tmp) { + skb_unlink(s, &llcp_sock->tx_pending_queue); + kfree_skb(s); + + if (nfc_llcp_ns(s) == nr) + break; + } + + /* Re-queue the remaining skbs for transmission */ + skb_queue_reverse_walk_safe(&llcp_sock->tx_pending_queue, + s, tmp) { + skb_unlink(s, &llcp_sock->tx_pending_queue); + skb_queue_head(&local->tx_queue, s); + } } if (ptype == LLCP_PDU_RR)