File-copy from v4.4.100
This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Please refer to that tree for all history prior to this point.
Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/net/irda/irttp.c b/net/irda/irttp.c
new file mode 100644
index 0000000..b6ab41d
--- /dev/null
+++ b/net/irda/irttp.c
@@ -0,0 +1,1891 @@
+/*********************************************************************
+ *
+ * Filename: irttp.c
+ * Version: 1.2
+ * Description: Tiny Transport Protocol (TTP) implementation
+ * Status: Stable
+ * Author: Dag Brattli <dagb@cs.uit.no>
+ * Created at: Sun Aug 31 20:14:31 1997
+ * Modified at: Wed Jan 5 11:31:27 2000
+ * Modified by: Dag Brattli <dagb@cs.uit.no>
+ *
+ * Copyright (c) 1998-2000 Dag Brattli <dagb@cs.uit.no>,
+ * All Rights Reserved.
+ * Copyright (c) 2000-2003 Jean Tourrilhes <jt@hpl.hp.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * Neither Dag Brattli nor University of Tromsø admit liability nor
+ * provide warranty for any of this software. This material is
+ * provided "AS-IS" and at no charge.
+ *
+ ********************************************************************/
+
+#include <linux/skbuff.h>
+#include <linux/init.h>
+#include <linux/fs.h>
+#include <linux/seq_file.h>
+#include <linux/slab.h>
+#include <linux/export.h>
+
+#include <asm/byteorder.h>
+#include <asm/unaligned.h>
+
+#include <net/irda/irda.h>
+#include <net/irda/irlap.h>
+#include <net/irda/irlmp.h>
+#include <net/irda/parameters.h>
+#include <net/irda/irttp.h>
+
+static struct irttp_cb *irttp;
+
+static void __irttp_close_tsap(struct tsap_cb *self);
+
+static int irttp_data_indication(void *instance, void *sap,
+ struct sk_buff *skb);
+static int irttp_udata_indication(void *instance, void *sap,
+ struct sk_buff *skb);
+static void irttp_disconnect_indication(void *instance, void *sap,
+ LM_REASON reason, struct sk_buff *);
+static void irttp_connect_indication(void *instance, void *sap,
+ struct qos_info *qos, __u32 max_sdu_size,
+ __u8 header_size, struct sk_buff *skb);
+static void irttp_connect_confirm(void *instance, void *sap,
+ struct qos_info *qos, __u32 max_sdu_size,
+ __u8 header_size, struct sk_buff *skb);
+static void irttp_run_tx_queue(struct tsap_cb *self);
+static void irttp_run_rx_queue(struct tsap_cb *self);
+
+static void irttp_flush_queues(struct tsap_cb *self);
+static void irttp_fragment_skb(struct tsap_cb *self, struct sk_buff *skb);
+static struct sk_buff *irttp_reassemble_skb(struct tsap_cb *self);
+static void irttp_todo_expired(unsigned long data);
+static int irttp_param_max_sdu_size(void *instance, irda_param_t *param,
+ int get);
+
+static void irttp_flow_indication(void *instance, void *sap, LOCAL_FLOW flow);
+static void irttp_status_indication(void *instance,
+ LINK_STATUS link, LOCK_STATUS lock);
+
+/* Information for parsing parameters in IrTTP */
+static const pi_minor_info_t pi_minor_call_table[] = {
+ { NULL, 0 }, /* 0x00 */
+ { irttp_param_max_sdu_size, PV_INTEGER | PV_BIG_ENDIAN } /* 0x01 */
+};
+static const pi_major_info_t pi_major_call_table[] = {
+ { pi_minor_call_table, 2 }
+};
+static pi_param_info_t param_info = { pi_major_call_table, 1, 0x0f, 4 };
+
+/************************ GLOBAL PROCEDURES ************************/
+
+/*
+ * Function irttp_init (void)
+ *
+ * Initialize the IrTTP layer. Called by module initialization code
+ *
+ */
+int __init irttp_init(void)
+{
+ irttp = kzalloc(sizeof(struct irttp_cb), GFP_KERNEL);
+ if (irttp == NULL)
+ return -ENOMEM;
+
+ irttp->magic = TTP_MAGIC;
+
+ irttp->tsaps = hashbin_new(HB_LOCK);
+ if (!irttp->tsaps) {
+ net_err_ratelimited("%s: can't allocate IrTTP hashbin!\n",
+ __func__);
+ kfree(irttp);
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+/*
+ * Function irttp_cleanup (void)
+ *
+ * Called by module destruction/cleanup code
+ *
+ */
+void irttp_cleanup(void)
+{
+ /* Check for main structure */
+ IRDA_ASSERT(irttp->magic == TTP_MAGIC, return;);
+
+ /*
+ * Delete hashbin and close all TSAP instances in it
+ */
+ hashbin_delete(irttp->tsaps, (FREE_FUNC) __irttp_close_tsap);
+
+ irttp->magic = 0;
+
+ /* De-allocate main structure */
+ kfree(irttp);
+
+ irttp = NULL;
+}
+
+/*************************** SUBROUTINES ***************************/
+
+/*
+ * Function irttp_start_todo_timer (self, timeout)
+ *
+ * Start todo timer.
+ *
+ * Made it more effient and unsensitive to race conditions - Jean II
+ */
+static inline void irttp_start_todo_timer(struct tsap_cb *self, int timeout)
+{
+ /* Set new value for timer */
+ mod_timer(&self->todo_timer, jiffies + timeout);
+}
+
+/*
+ * Function irttp_todo_expired (data)
+ *
+ * Todo timer has expired!
+ *
+ * One of the restriction of the timer is that it is run only on the timer
+ * interrupt which run every 10ms. This mean that even if you set the timer
+ * with a delay of 0, it may take up to 10ms before it's run.
+ * So, to minimise latency and keep cache fresh, we try to avoid using
+ * it as much as possible.
+ * Note : we can't use tasklets, because they can't be asynchronously
+ * killed (need user context), and we can't guarantee that here...
+ * Jean II
+ */
+static void irttp_todo_expired(unsigned long data)
+{
+ struct tsap_cb *self = (struct tsap_cb *) data;
+
+ /* Check that we still exist */
+ if (!self || self->magic != TTP_TSAP_MAGIC)
+ return;
+
+ pr_debug("%s(instance=%p)\n", __func__, self);
+
+ /* Try to make some progress, especially on Tx side - Jean II */
+ irttp_run_rx_queue(self);
+ irttp_run_tx_queue(self);
+
+ /* Check if time for disconnect */
+ if (test_bit(0, &self->disconnect_pend)) {
+ /* Check if it's possible to disconnect yet */
+ if (skb_queue_empty(&self->tx_queue)) {
+ /* Make sure disconnect is not pending anymore */
+ clear_bit(0, &self->disconnect_pend); /* FALSE */
+
+ /* Note : self->disconnect_skb may be NULL */
+ irttp_disconnect_request(self, self->disconnect_skb,
+ P_NORMAL);
+ self->disconnect_skb = NULL;
+ } else {
+ /* Try again later */
+ irttp_start_todo_timer(self, HZ/10);
+
+ /* No reason to try and close now */
+ return;
+ }
+ }
+
+ /* Check if it's closing time */
+ if (self->close_pend)
+ /* Finish cleanup */
+ irttp_close_tsap(self);
+}
+
+/*
+ * Function irttp_flush_queues (self)
+ *
+ * Flushes (removes all frames) in transitt-buffer (tx_list)
+ */
+static void irttp_flush_queues(struct tsap_cb *self)
+{
+ struct sk_buff *skb;
+
+ IRDA_ASSERT(self != NULL, return;);
+ IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
+
+ /* Deallocate frames waiting to be sent */
+ while ((skb = skb_dequeue(&self->tx_queue)) != NULL)
+ dev_kfree_skb(skb);
+
+ /* Deallocate received frames */
+ while ((skb = skb_dequeue(&self->rx_queue)) != NULL)
+ dev_kfree_skb(skb);
+
+ /* Deallocate received fragments */
+ while ((skb = skb_dequeue(&self->rx_fragments)) != NULL)
+ dev_kfree_skb(skb);
+}
+
+/*
+ * Function irttp_reassemble (self)
+ *
+ * Makes a new (continuous) skb of all the fragments in the fragment
+ * queue
+ *
+ */
+static struct sk_buff *irttp_reassemble_skb(struct tsap_cb *self)
+{
+ struct sk_buff *skb, *frag;
+ int n = 0; /* Fragment index */
+
+ IRDA_ASSERT(self != NULL, return NULL;);
+ IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return NULL;);
+
+ pr_debug("%s(), self->rx_sdu_size=%d\n", __func__,
+ self->rx_sdu_size);
+
+ skb = dev_alloc_skb(TTP_HEADER + self->rx_sdu_size);
+ if (!skb)
+ return NULL;
+
+ /*
+ * Need to reserve space for TTP header in case this skb needs to
+ * be requeued in case delivery failes
+ */
+ skb_reserve(skb, TTP_HEADER);
+ skb_put(skb, self->rx_sdu_size);
+
+ /*
+ * Copy all fragments to a new buffer
+ */
+ while ((frag = skb_dequeue(&self->rx_fragments)) != NULL) {
+ skb_copy_to_linear_data_offset(skb, n, frag->data, frag->len);
+ n += frag->len;
+
+ dev_kfree_skb(frag);
+ }
+
+ pr_debug("%s(), frame len=%d, rx_sdu_size=%d, rx_max_sdu_size=%d\n",
+ __func__, n, self->rx_sdu_size, self->rx_max_sdu_size);
+ /* Note : irttp_run_rx_queue() calculate self->rx_sdu_size
+ * by summing the size of all fragments, so we should always
+ * have n == self->rx_sdu_size, except in cases where we
+ * droped the last fragment (when self->rx_sdu_size exceed
+ * self->rx_max_sdu_size), where n < self->rx_sdu_size.
+ * Jean II */
+ IRDA_ASSERT(n <= self->rx_sdu_size, n = self->rx_sdu_size;);
+
+ /* Set the new length */
+ skb_trim(skb, n);
+
+ self->rx_sdu_size = 0;
+
+ return skb;
+}
+
+/*
+ * Function irttp_fragment_skb (skb)
+ *
+ * Fragments a frame and queues all the fragments for transmission
+ *
+ */
+static inline void irttp_fragment_skb(struct tsap_cb *self,
+ struct sk_buff *skb)
+{
+ struct sk_buff *frag;
+ __u8 *frame;
+
+ IRDA_ASSERT(self != NULL, return;);
+ IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
+ IRDA_ASSERT(skb != NULL, return;);
+
+ /*
+ * Split frame into a number of segments
+ */
+ while (skb->len > self->max_seg_size) {
+ pr_debug("%s(), fragmenting ...\n", __func__);
+
+ /* Make new segment */
+ frag = alloc_skb(self->max_seg_size+self->max_header_size,
+ GFP_ATOMIC);
+ if (!frag)
+ return;
+
+ skb_reserve(frag, self->max_header_size);
+
+ /* Copy data from the original skb into this fragment. */
+ skb_copy_from_linear_data(skb, skb_put(frag, self->max_seg_size),
+ self->max_seg_size);
+
+ /* Insert TTP header, with the more bit set */
+ frame = skb_push(frag, TTP_HEADER);
+ frame[0] = TTP_MORE;
+
+ /* Hide the copied data from the original skb */
+ skb_pull(skb, self->max_seg_size);
+
+ /* Queue fragment */
+ skb_queue_tail(&self->tx_queue, frag);
+ }
+ /* Queue what is left of the original skb */
+ pr_debug("%s(), queuing last segment\n", __func__);
+
+ frame = skb_push(skb, TTP_HEADER);
+ frame[0] = 0x00; /* Clear more bit */
+
+ /* Queue fragment */
+ skb_queue_tail(&self->tx_queue, skb);
+}
+
+/*
+ * Function irttp_param_max_sdu_size (self, param)
+ *
+ * Handle the MaxSduSize parameter in the connect frames, this function
+ * will be called both when this parameter needs to be inserted into, and
+ * extracted from the connect frames
+ */
+static int irttp_param_max_sdu_size(void *instance, irda_param_t *param,
+ int get)
+{
+ struct tsap_cb *self;
+
+ self = instance;
+
+ IRDA_ASSERT(self != NULL, return -1;);
+ IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;);
+
+ if (get)
+ param->pv.i = self->tx_max_sdu_size;
+ else
+ self->tx_max_sdu_size = param->pv.i;
+
+ pr_debug("%s(), MaxSduSize=%d\n", __func__, param->pv.i);
+
+ return 0;
+}
+
+/*************************** CLIENT CALLS ***************************/
+/************************** LMP CALLBACKS **************************/
+/* Everything is happily mixed up. Waiting for next clean up - Jean II */
+
+/*
+ * Initialization, that has to be done on new tsap
+ * instance allocation and on duplication
+ */
+static void irttp_init_tsap(struct tsap_cb *tsap)
+{
+ spin_lock_init(&tsap->lock);
+ init_timer(&tsap->todo_timer);
+
+ skb_queue_head_init(&tsap->rx_queue);
+ skb_queue_head_init(&tsap->tx_queue);
+ skb_queue_head_init(&tsap->rx_fragments);
+}
+
+/*
+ * Function irttp_open_tsap (stsap, notify)
+ *
+ * Create TSAP connection endpoint,
+ */
+struct tsap_cb *irttp_open_tsap(__u8 stsap_sel, int credit, notify_t *notify)
+{
+ struct tsap_cb *self;
+ struct lsap_cb *lsap;
+ notify_t ttp_notify;
+
+ IRDA_ASSERT(irttp->magic == TTP_MAGIC, return NULL;);
+
+ /* The IrLMP spec (IrLMP 1.1 p10) says that we have the right to
+ * use only 0x01-0x6F. Of course, we can use LSAP_ANY as well.
+ * JeanII */
+ if ((stsap_sel != LSAP_ANY) &&
+ ((stsap_sel < 0x01) || (stsap_sel >= 0x70))) {
+ pr_debug("%s(), invalid tsap!\n", __func__);
+ return NULL;
+ }
+
+ self = kzalloc(sizeof(struct tsap_cb), GFP_ATOMIC);
+ if (self == NULL)
+ return NULL;
+
+ /* Initialize internal objects */
+ irttp_init_tsap(self);
+
+ /* Initialise todo timer */
+ self->todo_timer.data = (unsigned long) self;
+ self->todo_timer.function = &irttp_todo_expired;
+
+ /* Initialize callbacks for IrLMP to use */
+ irda_notify_init(&ttp_notify);
+ ttp_notify.connect_confirm = irttp_connect_confirm;
+ ttp_notify.connect_indication = irttp_connect_indication;
+ ttp_notify.disconnect_indication = irttp_disconnect_indication;
+ ttp_notify.data_indication = irttp_data_indication;
+ ttp_notify.udata_indication = irttp_udata_indication;
+ ttp_notify.flow_indication = irttp_flow_indication;
+ if (notify->status_indication != NULL)
+ ttp_notify.status_indication = irttp_status_indication;
+ ttp_notify.instance = self;
+ strncpy(ttp_notify.name, notify->name, NOTIFY_MAX_NAME);
+
+ self->magic = TTP_TSAP_MAGIC;
+ self->connected = FALSE;
+
+ /*
+ * Create LSAP at IrLMP layer
+ */
+ lsap = irlmp_open_lsap(stsap_sel, &ttp_notify, 0);
+ if (lsap == NULL) {
+ pr_debug("%s: unable to allocate LSAP!!\n", __func__);
+ __irttp_close_tsap(self);
+ return NULL;
+ }
+
+ /*
+ * If user specified LSAP_ANY as source TSAP selector, then IrLMP
+ * will replace it with whatever source selector which is free, so
+ * the stsap_sel we have might not be valid anymore
+ */
+ self->stsap_sel = lsap->slsap_sel;
+ pr_debug("%s(), stsap_sel=%02x\n", __func__, self->stsap_sel);
+
+ self->notify = *notify;
+ self->lsap = lsap;
+
+ hashbin_insert(irttp->tsaps, (irda_queue_t *) self, (long) self, NULL);
+
+ if (credit > TTP_RX_MAX_CREDIT)
+ self->initial_credit = TTP_RX_MAX_CREDIT;
+ else
+ self->initial_credit = credit;
+
+ return self;
+}
+EXPORT_SYMBOL(irttp_open_tsap);
+
+/*
+ * Function irttp_close (handle)
+ *
+ * Remove an instance of a TSAP. This function should only deal with the
+ * deallocation of the TSAP, and resetting of the TSAPs values;
+ *
+ */
+static void __irttp_close_tsap(struct tsap_cb *self)
+{
+ /* First make sure we're connected. */
+ IRDA_ASSERT(self != NULL, return;);
+ IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
+
+ irttp_flush_queues(self);
+
+ del_timer(&self->todo_timer);
+
+ /* This one won't be cleaned up if we are disconnect_pend + close_pend
+ * and we receive a disconnect_indication */
+ if (self->disconnect_skb)
+ dev_kfree_skb(self->disconnect_skb);
+
+ self->connected = FALSE;
+ self->magic = ~TTP_TSAP_MAGIC;
+
+ kfree(self);
+}
+
+/*
+ * Function irttp_close (self)
+ *
+ * Remove TSAP from list of all TSAPs and then deallocate all resources
+ * associated with this TSAP
+ *
+ * Note : because we *free* the tsap structure, it is the responsibility
+ * of the caller to make sure we are called only once and to deal with
+ * possible race conditions. - Jean II
+ */
+int irttp_close_tsap(struct tsap_cb *self)
+{
+ struct tsap_cb *tsap;
+
+ IRDA_ASSERT(self != NULL, return -1;);
+ IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;);
+
+ /* Make sure tsap has been disconnected */
+ if (self->connected) {
+ /* Check if disconnect is not pending */
+ if (!test_bit(0, &self->disconnect_pend)) {
+ net_warn_ratelimited("%s: TSAP still connected!\n",
+ __func__);
+ irttp_disconnect_request(self, NULL, P_NORMAL);
+ }
+ self->close_pend = TRUE;
+ irttp_start_todo_timer(self, HZ/10);
+
+ return 0; /* Will be back! */
+ }
+
+ tsap = hashbin_remove(irttp->tsaps, (long) self, NULL);
+
+ IRDA_ASSERT(tsap == self, return -1;);
+
+ /* Close corresponding LSAP */
+ if (self->lsap) {
+ irlmp_close_lsap(self->lsap);
+ self->lsap = NULL;
+ }
+
+ __irttp_close_tsap(self);
+
+ return 0;
+}
+EXPORT_SYMBOL(irttp_close_tsap);
+
+/*
+ * Function irttp_udata_request (self, skb)
+ *
+ * Send unreliable data on this TSAP
+ *
+ */
+int irttp_udata_request(struct tsap_cb *self, struct sk_buff *skb)
+{
+ int ret;
+
+ IRDA_ASSERT(self != NULL, return -1;);
+ IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;);
+ IRDA_ASSERT(skb != NULL, return -1;);
+
+ /* Take shortcut on zero byte packets */
+ if (skb->len == 0) {
+ ret = 0;
+ goto err;
+ }
+
+ /* Check that nothing bad happens */
+ if (!self->connected) {
+ net_warn_ratelimited("%s(), Not connected\n", __func__);
+ ret = -ENOTCONN;
+ goto err;
+ }
+
+ if (skb->len > self->max_seg_size) {
+ net_err_ratelimited("%s(), UData is too large for IrLAP!\n",
+ __func__);
+ ret = -EMSGSIZE;
+ goto err;
+ }
+
+ irlmp_udata_request(self->lsap, skb);
+ self->stats.tx_packets++;
+
+ return 0;
+
+err:
+ dev_kfree_skb(skb);
+ return ret;
+}
+EXPORT_SYMBOL(irttp_udata_request);
+
+
+/*
+ * Function irttp_data_request (handle, skb)
+ *
+ * Queue frame for transmission. If SAR is enabled, fragement the frame
+ * and queue the fragments for transmission
+ */
+int irttp_data_request(struct tsap_cb *self, struct sk_buff *skb)
+{
+ __u8 *frame;
+ int ret;
+
+ IRDA_ASSERT(self != NULL, return -1;);
+ IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;);
+ IRDA_ASSERT(skb != NULL, return -1;);
+
+ pr_debug("%s() : queue len = %d\n", __func__,
+ skb_queue_len(&self->tx_queue));
+
+ /* Take shortcut on zero byte packets */
+ if (skb->len == 0) {
+ ret = 0;
+ goto err;
+ }
+
+ /* Check that nothing bad happens */
+ if (!self->connected) {
+ net_warn_ratelimited("%s: Not connected\n", __func__);
+ ret = -ENOTCONN;
+ goto err;
+ }
+
+ /*
+ * Check if SAR is disabled, and the frame is larger than what fits
+ * inside an IrLAP frame
+ */
+ if ((self->tx_max_sdu_size == 0) && (skb->len > self->max_seg_size)) {
+ net_err_ratelimited("%s: SAR disabled, and data is too large for IrLAP!\n",
+ __func__);
+ ret = -EMSGSIZE;
+ goto err;
+ }
+
+ /*
+ * Check if SAR is enabled, and the frame is larger than the
+ * TxMaxSduSize
+ */
+ if ((self->tx_max_sdu_size != 0) &&
+ (self->tx_max_sdu_size != TTP_SAR_UNBOUND) &&
+ (skb->len > self->tx_max_sdu_size)) {
+ net_err_ratelimited("%s: SAR enabled, but data is larger than TxMaxSduSize!\n",
+ __func__);
+ ret = -EMSGSIZE;
+ goto err;
+ }
+ /*
+ * Check if transmit queue is full
+ */
+ if (skb_queue_len(&self->tx_queue) >= TTP_TX_MAX_QUEUE) {
+ /*
+ * Give it a chance to empty itself
+ */
+ irttp_run_tx_queue(self);
+
+ /* Drop packet. This error code should trigger the caller
+ * to resend the data in the client code - Jean II */
+ ret = -ENOBUFS;
+ goto err;
+ }
+
+ /* Queue frame, or queue frame segments */
+ if ((self->tx_max_sdu_size == 0) || (skb->len < self->max_seg_size)) {
+ /* Queue frame */
+ IRDA_ASSERT(skb_headroom(skb) >= TTP_HEADER, return -1;);
+ frame = skb_push(skb, TTP_HEADER);
+ frame[0] = 0x00; /* Clear more bit */
+
+ skb_queue_tail(&self->tx_queue, skb);
+ } else {
+ /*
+ * Fragment the frame, this function will also queue the
+ * fragments, we don't care about the fact the transmit
+ * queue may be overfilled by all the segments for a little
+ * while
+ */
+ irttp_fragment_skb(self, skb);
+ }
+
+ /* Check if we can accept more data from client */
+ if ((!self->tx_sdu_busy) &&
+ (skb_queue_len(&self->tx_queue) > TTP_TX_HIGH_THRESHOLD)) {
+ /* Tx queue filling up, so stop client. */
+ if (self->notify.flow_indication) {
+ self->notify.flow_indication(self->notify.instance,
+ self, FLOW_STOP);
+ }
+ /* self->tx_sdu_busy is the state of the client.
+ * Update state after notifying client to avoid
+ * race condition with irttp_flow_indication().
+ * If the queue empty itself after our test but before
+ * we set the flag, we will fix ourselves below in
+ * irttp_run_tx_queue().
+ * Jean II */
+ self->tx_sdu_busy = TRUE;
+ }
+
+ /* Try to make some progress */
+ irttp_run_tx_queue(self);
+
+ return 0;
+
+err:
+ dev_kfree_skb(skb);
+ return ret;
+}
+EXPORT_SYMBOL(irttp_data_request);
+
+/*
+ * Function irttp_run_tx_queue (self)
+ *
+ * Transmit packets queued for transmission (if possible)
+ *
+ */
+static void irttp_run_tx_queue(struct tsap_cb *self)
+{
+ struct sk_buff *skb;
+ unsigned long flags;
+ int n;
+
+ pr_debug("%s() : send_credit = %d, queue_len = %d\n",
+ __func__,
+ self->send_credit, skb_queue_len(&self->tx_queue));
+
+ /* Get exclusive access to the tx queue, otherwise don't touch it */
+ if (irda_lock(&self->tx_queue_lock) == FALSE)
+ return;
+
+ /* Try to send out frames as long as we have credits
+ * and as long as LAP is not full. If LAP is full, it will
+ * poll us through irttp_flow_indication() - Jean II */
+ while ((self->send_credit > 0) &&
+ (!irlmp_lap_tx_queue_full(self->lsap)) &&
+ (skb = skb_dequeue(&self->tx_queue))) {
+ /*
+ * Since we can transmit and receive frames concurrently,
+ * the code below is a critical region and we must assure that
+ * nobody messes with the credits while we update them.
+ */
+ spin_lock_irqsave(&self->lock, flags);
+
+ n = self->avail_credit;
+ self->avail_credit = 0;
+
+ /* Only room for 127 credits in frame */
+ if (n > 127) {
+ self->avail_credit = n-127;
+ n = 127;
+ }
+ self->remote_credit += n;
+ self->send_credit--;
+
+ spin_unlock_irqrestore(&self->lock, flags);
+
+ /*
+ * More bit must be set by the data_request() or fragment()
+ * functions
+ */
+ skb->data[0] |= (n & 0x7f);
+
+ /* Detach from socket.
+ * The current skb has a reference to the socket that sent
+ * it (skb->sk). When we pass it to IrLMP, the skb will be
+ * stored in in IrLAP (self->wx_list). When we are within
+ * IrLAP, we lose the notion of socket, so we should not
+ * have a reference to a socket. So, we drop it here.
+ *
+ * Why does it matter ?
+ * When the skb is freed (kfree_skb), if it is associated
+ * with a socket, it release buffer space on the socket
+ * (through sock_wfree() and sock_def_write_space()).
+ * If the socket no longer exist, we may crash. Hard.
+ * When we close a socket, we make sure that associated packets
+ * in IrTTP are freed. However, we have no way to cancel
+ * the packet that we have passed to IrLAP. So, if a packet
+ * remains in IrLAP (retry on the link or else) after we
+ * close the socket, we are dead !
+ * Jean II */
+ if (skb->sk != NULL) {
+ /* IrSOCK application, IrOBEX, ... */
+ skb_orphan(skb);
+ }
+ /* IrCOMM over IrTTP, IrLAN, ... */
+
+ /* Pass the skb to IrLMP - done */
+ irlmp_data_request(self->lsap, skb);
+ self->stats.tx_packets++;
+ }
+
+ /* Check if we can accept more frames from client.
+ * We don't want to wait until the todo timer to do that, and we
+ * can't use tasklets (grr...), so we are obliged to give control
+ * to client. That's ok, this test will be true not too often
+ * (max once per LAP window) and we are called from places
+ * where we can spend a bit of time doing stuff. - Jean II */
+ if ((self->tx_sdu_busy) &&
+ (skb_queue_len(&self->tx_queue) < TTP_TX_LOW_THRESHOLD) &&
+ (!self->close_pend)) {
+ if (self->notify.flow_indication)
+ self->notify.flow_indication(self->notify.instance,
+ self, FLOW_START);
+
+ /* self->tx_sdu_busy is the state of the client.
+ * We don't really have a race here, but it's always safer
+ * to update our state after the client - Jean II */
+ self->tx_sdu_busy = FALSE;
+ }
+
+ /* Reset lock */
+ self->tx_queue_lock = 0;
+}
+
+/*
+ * Function irttp_give_credit (self)
+ *
+ * Send a dataless flowdata TTP-PDU and give available credit to peer
+ * TSAP
+ */
+static inline void irttp_give_credit(struct tsap_cb *self)
+{
+ struct sk_buff *tx_skb = NULL;
+ unsigned long flags;
+ int n;
+
+ IRDA_ASSERT(self != NULL, return;);
+ IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
+
+ pr_debug("%s() send=%d,avail=%d,remote=%d\n",
+ __func__,
+ self->send_credit, self->avail_credit, self->remote_credit);
+
+ /* Give credit to peer */
+ tx_skb = alloc_skb(TTP_MAX_HEADER, GFP_ATOMIC);
+ if (!tx_skb)
+ return;
+
+ /* Reserve space for LMP, and LAP header */
+ skb_reserve(tx_skb, LMP_MAX_HEADER);
+
+ /*
+ * Since we can transmit and receive frames concurrently,
+ * the code below is a critical region and we must assure that
+ * nobody messes with the credits while we update them.
+ */
+ spin_lock_irqsave(&self->lock, flags);
+
+ n = self->avail_credit;
+ self->avail_credit = 0;
+
+ /* Only space for 127 credits in frame */
+ if (n > 127) {
+ self->avail_credit = n - 127;
+ n = 127;
+ }
+ self->remote_credit += n;
+
+ spin_unlock_irqrestore(&self->lock, flags);
+
+ skb_put(tx_skb, 1);
+ tx_skb->data[0] = (__u8) (n & 0x7f);
+
+ irlmp_data_request(self->lsap, tx_skb);
+ self->stats.tx_packets++;
+}
+
+/*
+ * Function irttp_udata_indication (instance, sap, skb)
+ *
+ * Received some unit-data (unreliable)
+ *
+ */
+static int irttp_udata_indication(void *instance, void *sap,
+ struct sk_buff *skb)
+{
+ struct tsap_cb *self;
+ int err;
+
+ self = instance;
+
+ IRDA_ASSERT(self != NULL, return -1;);
+ IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;);
+ IRDA_ASSERT(skb != NULL, return -1;);
+
+ self->stats.rx_packets++;
+
+ /* Just pass data to layer above */
+ if (self->notify.udata_indication) {
+ err = self->notify.udata_indication(self->notify.instance,
+ self, skb);
+ /* Same comment as in irttp_do_data_indication() */
+ if (!err)
+ return 0;
+ }
+ /* Either no handler, or handler returns an error */
+ dev_kfree_skb(skb);
+
+ return 0;
+}
+
+/*
+ * Function irttp_data_indication (instance, sap, skb)
+ *
+ * Receive segment from IrLMP.
+ *
+ */
+static int irttp_data_indication(void *instance, void *sap,
+ struct sk_buff *skb)
+{
+ struct tsap_cb *self;
+ unsigned long flags;
+ int n;
+
+ self = instance;
+
+ n = skb->data[0] & 0x7f; /* Extract the credits */
+
+ self->stats.rx_packets++;
+
+ /* Deal with inbound credit
+ * Since we can transmit and receive frames concurrently,
+ * the code below is a critical region and we must assure that
+ * nobody messes with the credits while we update them.
+ */
+ spin_lock_irqsave(&self->lock, flags);
+ self->send_credit += n;
+ if (skb->len > 1)
+ self->remote_credit--;
+ spin_unlock_irqrestore(&self->lock, flags);
+
+ /*
+ * Data or dataless packet? Dataless frames contains only the
+ * TTP_HEADER.
+ */
+ if (skb->len > 1) {
+ /*
+ * We don't remove the TTP header, since we must preserve the
+ * more bit, so the defragment routing knows what to do
+ */
+ skb_queue_tail(&self->rx_queue, skb);
+ } else {
+ /* Dataless flowdata TTP-PDU */
+ dev_kfree_skb(skb);
+ }
+
+
+ /* Push data to the higher layer.
+ * We do it synchronously because running the todo timer for each
+ * receive packet would be too much overhead and latency.
+ * By passing control to the higher layer, we run the risk that
+ * it may take time or grab a lock. Most often, the higher layer
+ * will only put packet in a queue.
+ * Anyway, packets are only dripping through the IrDA, so we can
+ * have time before the next packet.
+ * Further, we are run from NET_BH, so the worse that can happen is
+ * us missing the optimal time to send back the PF bit in LAP.
+ * Jean II */
+ irttp_run_rx_queue(self);
+
+ /* We now give credits to peer in irttp_run_rx_queue().
+ * We need to send credit *NOW*, otherwise we are going
+ * to miss the next Tx window. The todo timer may take
+ * a while before it's run... - Jean II */
+
+ /*
+ * If the peer device has given us some credits and we didn't have
+ * anyone from before, then we need to shedule the tx queue.
+ * We need to do that because our Tx have stopped (so we may not
+ * get any LAP flow indication) and the user may be stopped as
+ * well. - Jean II
+ */
+ if (self->send_credit == n) {
+ /* Restart pushing stuff to LAP */
+ irttp_run_tx_queue(self);
+ /* Note : we don't want to schedule the todo timer
+ * because it has horrible latency. No tasklets
+ * because the tasklet API is broken. - Jean II */
+ }
+
+ return 0;
+}
+
+/*
+ * Function irttp_status_indication (self, reason)
+ *
+ * Status_indication, just pass to the higher layer...
+ *
+ */
+static void irttp_status_indication(void *instance,
+ LINK_STATUS link, LOCK_STATUS lock)
+{
+ struct tsap_cb *self;
+
+ self = instance;
+
+ IRDA_ASSERT(self != NULL, return;);
+ IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
+
+ /* Check if client has already closed the TSAP and gone away */
+ if (self->close_pend)
+ return;
+
+ /*
+ * Inform service user if he has requested it
+ */
+ if (self->notify.status_indication != NULL)
+ self->notify.status_indication(self->notify.instance,
+ link, lock);
+ else
+ pr_debug("%s(), no handler\n", __func__);
+}
+
+/*
+ * Function irttp_flow_indication (self, reason)
+ *
+ * Flow_indication : IrLAP tells us to send more data.
+ *
+ */
+static void irttp_flow_indication(void *instance, void *sap, LOCAL_FLOW flow)
+{
+ struct tsap_cb *self;
+
+ self = instance;
+
+ IRDA_ASSERT(self != NULL, return;);
+ IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
+
+ pr_debug("%s(instance=%p)\n", __func__, self);
+
+ /* We are "polled" directly from LAP, and the LAP want to fill
+ * its Tx window. We want to do our best to send it data, so that
+ * we maximise the window. On the other hand, we want to limit the
+ * amount of work here so that LAP doesn't hang forever waiting
+ * for packets. - Jean II */
+
+ /* Try to send some packets. Currently, LAP calls us every time
+ * there is one free slot, so we will send only one packet.
+ * This allow the scheduler to do its round robin - Jean II */
+ irttp_run_tx_queue(self);
+
+ /* Note regarding the interraction with higher layer.
+ * irttp_run_tx_queue() may call the client when its queue
+ * start to empty, via notify.flow_indication(). Initially.
+ * I wanted this to happen in a tasklet, to avoid client
+ * grabbing the CPU, but we can't use tasklets safely. And timer
+ * is definitely too slow.
+ * This will happen only once per LAP window, and usually at
+ * the third packet (unless window is smaller). LAP is still
+ * doing mtt and sending first packet so it's sort of OK
+ * to do that. Jean II */
+
+ /* If we need to send disconnect. try to do it now */
+ if (self->disconnect_pend)
+ irttp_start_todo_timer(self, 0);
+}
+
+/*
+ * Function irttp_flow_request (self, command)
+ *
+ * This function could be used by the upper layers to tell IrTTP to stop
+ * delivering frames if the receive queues are starting to get full, or
+ * to tell IrTTP to start delivering frames again.
+ */
+void irttp_flow_request(struct tsap_cb *self, LOCAL_FLOW flow)
+{
+ IRDA_ASSERT(self != NULL, return;);
+ IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
+
+ switch (flow) {
+ case FLOW_STOP:
+ pr_debug("%s(), flow stop\n", __func__);
+ self->rx_sdu_busy = TRUE;
+ break;
+ case FLOW_START:
+ pr_debug("%s(), flow start\n", __func__);
+ self->rx_sdu_busy = FALSE;
+
+ /* Client say he can accept more data, try to free our
+ * queues ASAP - Jean II */
+ irttp_run_rx_queue(self);
+
+ break;
+ default:
+ pr_debug("%s(), Unknown flow command!\n", __func__);
+ }
+}
+EXPORT_SYMBOL(irttp_flow_request);
+
+/*
+ * Function irttp_connect_request (self, dtsap_sel, daddr, qos)
+ *
+ * Try to connect to remote destination TSAP selector
+ *
+ */
+int irttp_connect_request(struct tsap_cb *self, __u8 dtsap_sel,
+ __u32 saddr, __u32 daddr,
+ struct qos_info *qos, __u32 max_sdu_size,
+ struct sk_buff *userdata)
+{
+ struct sk_buff *tx_skb;
+ __u8 *frame;
+ __u8 n;
+
+ pr_debug("%s(), max_sdu_size=%d\n", __func__, max_sdu_size);
+
+ IRDA_ASSERT(self != NULL, return -EBADR;);
+ IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -EBADR;);
+
+ if (self->connected) {
+ if (userdata)
+ dev_kfree_skb(userdata);
+ return -EISCONN;
+ }
+
+ /* Any userdata supplied? */
+ if (userdata == NULL) {
+ tx_skb = alloc_skb(TTP_MAX_HEADER + TTP_SAR_HEADER,
+ GFP_ATOMIC);
+ if (!tx_skb)
+ return -ENOMEM;
+
+ /* Reserve space for MUX_CONTROL and LAP header */
+ skb_reserve(tx_skb, TTP_MAX_HEADER + TTP_SAR_HEADER);
+ } else {
+ tx_skb = userdata;
+ /*
+ * Check that the client has reserved enough space for
+ * headers
+ */
+ IRDA_ASSERT(skb_headroom(userdata) >= TTP_MAX_HEADER,
+ { dev_kfree_skb(userdata); return -1; });
+ }
+
+ /* Initialize connection parameters */
+ self->connected = FALSE;
+ self->avail_credit = 0;
+ self->rx_max_sdu_size = max_sdu_size;
+ self->rx_sdu_size = 0;
+ self->rx_sdu_busy = FALSE;
+ self->dtsap_sel = dtsap_sel;
+
+ n = self->initial_credit;
+
+ self->remote_credit = 0;
+ self->send_credit = 0;
+
+ /*
+ * Give away max 127 credits for now
+ */
+ if (n > 127) {
+ self->avail_credit = n - 127;
+ n = 127;
+ }
+
+ self->remote_credit = n;
+
+ /* SAR enabled? */
+ if (max_sdu_size > 0) {
+ IRDA_ASSERT(skb_headroom(tx_skb) >= (TTP_MAX_HEADER + TTP_SAR_HEADER),
+ { dev_kfree_skb(tx_skb); return -1; });
+
+ /* Insert SAR parameters */
+ frame = skb_push(tx_skb, TTP_HEADER + TTP_SAR_HEADER);
+
+ frame[0] = TTP_PARAMETERS | n;
+ frame[1] = 0x04; /* Length */
+ frame[2] = 0x01; /* MaxSduSize */
+ frame[3] = 0x02; /* Value length */
+
+ put_unaligned(cpu_to_be16((__u16) max_sdu_size),
+ (__be16 *)(frame+4));
+ } else {
+ /* Insert plain TTP header */
+ frame = skb_push(tx_skb, TTP_HEADER);
+
+ /* Insert initial credit in frame */
+ frame[0] = n & 0x7f;
+ }
+
+ /* Connect with IrLMP. No QoS parameters for now */
+ return irlmp_connect_request(self->lsap, dtsap_sel, saddr, daddr, qos,
+ tx_skb);
+}
+EXPORT_SYMBOL(irttp_connect_request);
+
+/*
+ * Function irttp_connect_confirm (handle, qos, skb)
+ *
+ * Service user confirms TSAP connection with peer.
+ *
+ */
+static void irttp_connect_confirm(void *instance, void *sap,
+ struct qos_info *qos, __u32 max_seg_size,
+ __u8 max_header_size, struct sk_buff *skb)
+{
+ struct tsap_cb *self;
+ int parameters;
+ int ret;
+ __u8 plen;
+ __u8 n;
+
+ self = instance;
+
+ IRDA_ASSERT(self != NULL, return;);
+ IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
+ IRDA_ASSERT(skb != NULL, return;);
+
+ self->max_seg_size = max_seg_size - TTP_HEADER;
+ self->max_header_size = max_header_size + TTP_HEADER;
+
+ /*
+ * Check if we have got some QoS parameters back! This should be the
+ * negotiated QoS for the link.
+ */
+ if (qos) {
+ pr_debug("IrTTP, Negotiated BAUD_RATE: %02x\n",
+ qos->baud_rate.bits);
+ pr_debug("IrTTP, Negotiated BAUD_RATE: %d bps.\n",
+ qos->baud_rate.value);
+ }
+
+ n = skb->data[0] & 0x7f;
+
+ pr_debug("%s(), Initial send_credit=%d\n", __func__, n);
+
+ self->send_credit = n;
+ self->tx_max_sdu_size = 0;
+ self->connected = TRUE;
+
+ parameters = skb->data[0] & 0x80;
+
+ IRDA_ASSERT(skb->len >= TTP_HEADER, return;);
+ skb_pull(skb, TTP_HEADER);
+
+ if (parameters) {
+ plen = skb->data[0];
+
+ ret = irda_param_extract_all(self, skb->data+1,
+ IRDA_MIN(skb->len-1, plen),
+ ¶m_info);
+
+ /* Any errors in the parameter list? */
+ if (ret < 0) {
+ net_warn_ratelimited("%s: error extracting parameters\n",
+ __func__);
+ dev_kfree_skb(skb);
+
+ /* Do not accept this connection attempt */
+ return;
+ }
+ /* Remove parameters */
+ skb_pull(skb, IRDA_MIN(skb->len, plen+1));
+ }
+
+ pr_debug("%s() send=%d,avail=%d,remote=%d\n", __func__,
+ self->send_credit, self->avail_credit, self->remote_credit);
+
+ pr_debug("%s(), MaxSduSize=%d\n", __func__,
+ self->tx_max_sdu_size);
+
+ if (self->notify.connect_confirm) {
+ self->notify.connect_confirm(self->notify.instance, self, qos,
+ self->tx_max_sdu_size,
+ self->max_header_size, skb);
+ } else
+ dev_kfree_skb(skb);
+}
+
+/*
+ * Function irttp_connect_indication (handle, skb)
+ *
+ * Some other device is connecting to this TSAP
+ *
+ */
+static void irttp_connect_indication(void *instance, void *sap,
+ struct qos_info *qos, __u32 max_seg_size, __u8 max_header_size,
+ struct sk_buff *skb)
+{
+ struct tsap_cb *self;
+ struct lsap_cb *lsap;
+ int parameters;
+ int ret;
+ __u8 plen;
+ __u8 n;
+
+ self = instance;
+
+ IRDA_ASSERT(self != NULL, return;);
+ IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
+ IRDA_ASSERT(skb != NULL, return;);
+
+ lsap = sap;
+
+ self->max_seg_size = max_seg_size - TTP_HEADER;
+ self->max_header_size = max_header_size+TTP_HEADER;
+
+ pr_debug("%s(), TSAP sel=%02x\n", __func__, self->stsap_sel);
+
+ /* Need to update dtsap_sel if its equal to LSAP_ANY */
+ self->dtsap_sel = lsap->dlsap_sel;
+
+ n = skb->data[0] & 0x7f;
+
+ self->send_credit = n;
+ self->tx_max_sdu_size = 0;
+
+ parameters = skb->data[0] & 0x80;
+
+ IRDA_ASSERT(skb->len >= TTP_HEADER, return;);
+ skb_pull(skb, TTP_HEADER);
+
+ if (parameters) {
+ plen = skb->data[0];
+
+ ret = irda_param_extract_all(self, skb->data+1,
+ IRDA_MIN(skb->len-1, plen),
+ ¶m_info);
+
+ /* Any errors in the parameter list? */
+ if (ret < 0) {
+ net_warn_ratelimited("%s: error extracting parameters\n",
+ __func__);
+ dev_kfree_skb(skb);
+
+ /* Do not accept this connection attempt */
+ return;
+ }
+
+ /* Remove parameters */
+ skb_pull(skb, IRDA_MIN(skb->len, plen+1));
+ }
+
+ if (self->notify.connect_indication) {
+ self->notify.connect_indication(self->notify.instance, self,
+ qos, self->tx_max_sdu_size,
+ self->max_header_size, skb);
+ } else
+ dev_kfree_skb(skb);
+}
+
+/*
+ * Function irttp_connect_response (handle, userdata)
+ *
+ * Service user is accepting the connection, just pass it down to
+ * IrLMP!
+ *
+ */
+int irttp_connect_response(struct tsap_cb *self, __u32 max_sdu_size,
+ struct sk_buff *userdata)
+{
+ struct sk_buff *tx_skb;
+ __u8 *frame;
+ int ret;
+ __u8 n;
+
+ IRDA_ASSERT(self != NULL, return -1;);
+ IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;);
+
+ pr_debug("%s(), Source TSAP selector=%02x\n", __func__,
+ self->stsap_sel);
+
+ /* Any userdata supplied? */
+ if (userdata == NULL) {
+ tx_skb = alloc_skb(TTP_MAX_HEADER + TTP_SAR_HEADER,
+ GFP_ATOMIC);
+ if (!tx_skb)
+ return -ENOMEM;
+
+ /* Reserve space for MUX_CONTROL and LAP header */
+ skb_reserve(tx_skb, TTP_MAX_HEADER + TTP_SAR_HEADER);
+ } else {
+ tx_skb = userdata;
+ /*
+ * Check that the client has reserved enough space for
+ * headers
+ */
+ IRDA_ASSERT(skb_headroom(userdata) >= TTP_MAX_HEADER,
+ { dev_kfree_skb(userdata); return -1; });
+ }
+
+ self->avail_credit = 0;
+ self->remote_credit = 0;
+ self->rx_max_sdu_size = max_sdu_size;
+ self->rx_sdu_size = 0;
+ self->rx_sdu_busy = FALSE;
+
+ n = self->initial_credit;
+
+ /* Frame has only space for max 127 credits (7 bits) */
+ if (n > 127) {
+ self->avail_credit = n - 127;
+ n = 127;
+ }
+
+ self->remote_credit = n;
+ self->connected = TRUE;
+
+ /* SAR enabled? */
+ if (max_sdu_size > 0) {
+ IRDA_ASSERT(skb_headroom(tx_skb) >= (TTP_MAX_HEADER + TTP_SAR_HEADER),
+ { dev_kfree_skb(tx_skb); return -1; });
+
+ /* Insert TTP header with SAR parameters */
+ frame = skb_push(tx_skb, TTP_HEADER + TTP_SAR_HEADER);
+
+ frame[0] = TTP_PARAMETERS | n;
+ frame[1] = 0x04; /* Length */
+
+ /* irda_param_insert(self, IRTTP_MAX_SDU_SIZE, frame+1, */
+/* TTP_SAR_HEADER, ¶m_info) */
+
+ frame[2] = 0x01; /* MaxSduSize */
+ frame[3] = 0x02; /* Value length */
+
+ put_unaligned(cpu_to_be16((__u16) max_sdu_size),
+ (__be16 *)(frame+4));
+ } else {
+ /* Insert TTP header */
+ frame = skb_push(tx_skb, TTP_HEADER);
+
+ frame[0] = n & 0x7f;
+ }
+
+ ret = irlmp_connect_response(self->lsap, tx_skb);
+
+ return ret;
+}
+EXPORT_SYMBOL(irttp_connect_response);
+
+/*
+ * Function irttp_dup (self, instance)
+ *
+ * Duplicate TSAP, can be used by servers to confirm a connection on a
+ * new TSAP so it can keep listening on the old one.
+ */
+struct tsap_cb *irttp_dup(struct tsap_cb *orig, void *instance)
+{
+ struct tsap_cb *new;
+ unsigned long flags;
+
+ /* Protect our access to the old tsap instance */
+ spin_lock_irqsave(&irttp->tsaps->hb_spinlock, flags);
+
+ /* Find the old instance */
+ if (!hashbin_find(irttp->tsaps, (long) orig, NULL)) {
+ pr_debug("%s(), unable to find TSAP\n", __func__);
+ spin_unlock_irqrestore(&irttp->tsaps->hb_spinlock, flags);
+ return NULL;
+ }
+
+ /* Allocate a new instance */
+ new = kmemdup(orig, sizeof(struct tsap_cb), GFP_ATOMIC);
+ if (!new) {
+ pr_debug("%s(), unable to kmalloc\n", __func__);
+ spin_unlock_irqrestore(&irttp->tsaps->hb_spinlock, flags);
+ return NULL;
+ }
+ spin_lock_init(&new->lock);
+
+ /* We don't need the old instance any more */
+ spin_unlock_irqrestore(&irttp->tsaps->hb_spinlock, flags);
+
+ /* Try to dup the LSAP (may fail if we were too slow) */
+ new->lsap = irlmp_dup(orig->lsap, new);
+ if (!new->lsap) {
+ pr_debug("%s(), dup failed!\n", __func__);
+ kfree(new);
+ return NULL;
+ }
+
+ /* Not everything should be copied */
+ new->notify.instance = instance;
+
+ /* Initialize internal objects */
+ irttp_init_tsap(new);
+
+ /* This is locked */
+ hashbin_insert(irttp->tsaps, (irda_queue_t *) new, (long) new, NULL);
+
+ return new;
+}
+EXPORT_SYMBOL(irttp_dup);
+
+/*
+ * Function irttp_disconnect_request (self)
+ *
+ * Close this connection please! If priority is high, the queued data
+ * segments, if any, will be deallocated first
+ *
+ */
+int irttp_disconnect_request(struct tsap_cb *self, struct sk_buff *userdata,
+ int priority)
+{
+ int ret;
+
+ IRDA_ASSERT(self != NULL, return -1;);
+ IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;);
+
+ /* Already disconnected? */
+ if (!self->connected) {
+ pr_debug("%s(), already disconnected!\n", __func__);
+ if (userdata)
+ dev_kfree_skb(userdata);
+ return -1;
+ }
+
+ /* Disconnect already pending ?
+ * We need to use an atomic operation to prevent reentry. This
+ * function may be called from various context, like user, timer
+ * for following a disconnect_indication() (i.e. net_bh).
+ * Jean II */
+ if (test_and_set_bit(0, &self->disconnect_pend)) {
+ pr_debug("%s(), disconnect already pending\n",
+ __func__);
+ if (userdata)
+ dev_kfree_skb(userdata);
+
+ /* Try to make some progress */
+ irttp_run_tx_queue(self);
+ return -1;
+ }
+
+ /*
+ * Check if there is still data segments in the transmit queue
+ */
+ if (!skb_queue_empty(&self->tx_queue)) {
+ if (priority == P_HIGH) {
+ /*
+ * No need to send the queued data, if we are
+ * disconnecting right now since the data will
+ * not have any usable connection to be sent on
+ */
+ pr_debug("%s(): High priority!!()\n", __func__);
+ irttp_flush_queues(self);
+ } else if (priority == P_NORMAL) {
+ /*
+ * Must delay disconnect until after all data segments
+ * have been sent and the tx_queue is empty
+ */
+ /* We'll reuse this one later for the disconnect */
+ self->disconnect_skb = userdata; /* May be NULL */
+
+ irttp_run_tx_queue(self);
+
+ irttp_start_todo_timer(self, HZ/10);
+ return -1;
+ }
+ }
+ /* Note : we don't need to check if self->rx_queue is full and the
+ * state of self->rx_sdu_busy because the disconnect response will
+ * be sent at the LMP level (so even if the peer has its Tx queue
+ * full of data). - Jean II */
+
+ pr_debug("%s(), Disconnecting ...\n", __func__);
+ self->connected = FALSE;
+
+ if (!userdata) {
+ struct sk_buff *tx_skb;
+ tx_skb = alloc_skb(LMP_MAX_HEADER, GFP_ATOMIC);
+ if (!tx_skb)
+ return -ENOMEM;
+
+ /*
+ * Reserve space for MUX and LAP header
+ */
+ skb_reserve(tx_skb, LMP_MAX_HEADER);
+
+ userdata = tx_skb;
+ }
+ ret = irlmp_disconnect_request(self->lsap, userdata);
+
+ /* The disconnect is no longer pending */
+ clear_bit(0, &self->disconnect_pend); /* FALSE */
+
+ return ret;
+}
+EXPORT_SYMBOL(irttp_disconnect_request);
+
+/*
+ * Function irttp_disconnect_indication (self, reason)
+ *
+ * Disconnect indication, TSAP disconnected by peer?
+ *
+ */
+static void irttp_disconnect_indication(void *instance, void *sap,
+ LM_REASON reason, struct sk_buff *skb)
+{
+ struct tsap_cb *self;
+
+ self = instance;
+
+ IRDA_ASSERT(self != NULL, return;);
+ IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
+
+ /* Prevent higher layer to send more data */
+ self->connected = FALSE;
+
+ /* Check if client has already tried to close the TSAP */
+ if (self->close_pend) {
+ /* In this case, the higher layer is probably gone. Don't
+ * bother it and clean up the remains - Jean II */
+ if (skb)
+ dev_kfree_skb(skb);
+ irttp_close_tsap(self);
+ return;
+ }
+
+ /* If we are here, we assume that is the higher layer is still
+ * waiting for the disconnect notification and able to process it,
+ * even if he tried to disconnect. Otherwise, it would have already
+ * attempted to close the tsap and self->close_pend would be TRUE.
+ * Jean II */
+
+ /* No need to notify the client if has already tried to disconnect */
+ if (self->notify.disconnect_indication)
+ self->notify.disconnect_indication(self->notify.instance, self,
+ reason, skb);
+ else
+ if (skb)
+ dev_kfree_skb(skb);
+}
+
+/*
+ * Function irttp_do_data_indication (self, skb)
+ *
+ * Try to deliver reassembled skb to layer above, and requeue it if that
+ * for some reason should fail. We mark rx sdu as busy to apply back
+ * pressure is necessary.
+ */
+static void irttp_do_data_indication(struct tsap_cb *self, struct sk_buff *skb)
+{
+ int err;
+
+ /* Check if client has already closed the TSAP and gone away */
+ if (self->close_pend) {
+ dev_kfree_skb(skb);
+ return;
+ }
+
+ err = self->notify.data_indication(self->notify.instance, self, skb);
+
+ /* Usually the layer above will notify that it's input queue is
+ * starting to get filled by using the flow request, but this may
+ * be difficult, so it can instead just refuse to eat it and just
+ * give an error back
+ */
+ if (err) {
+ pr_debug("%s() requeueing skb!\n", __func__);
+
+ /* Make sure we take a break */
+ self->rx_sdu_busy = TRUE;
+
+ /* Need to push the header in again */
+ skb_push(skb, TTP_HEADER);
+ skb->data[0] = 0x00; /* Make sure MORE bit is cleared */
+
+ /* Put skb back on queue */
+ skb_queue_head(&self->rx_queue, skb);
+ }
+}
+
+/*
+ * Function irttp_run_rx_queue (self)
+ *
+ * Check if we have any frames to be transmitted, or if we have any
+ * available credit to give away.
+ */
+static void irttp_run_rx_queue(struct tsap_cb *self)
+{
+ struct sk_buff *skb;
+ int more = 0;
+
+ pr_debug("%s() send=%d,avail=%d,remote=%d\n", __func__,
+ self->send_credit, self->avail_credit, self->remote_credit);
+
+ /* Get exclusive access to the rx queue, otherwise don't touch it */
+ if (irda_lock(&self->rx_queue_lock) == FALSE)
+ return;
+
+ /*
+ * Reassemble all frames in receive queue and deliver them
+ */
+ while (!self->rx_sdu_busy && (skb = skb_dequeue(&self->rx_queue))) {
+ /* This bit will tell us if it's the last fragment or not */
+ more = skb->data[0] & 0x80;
+
+ /* Remove TTP header */
+ skb_pull(skb, TTP_HEADER);
+
+ /* Add the length of the remaining data */
+ self->rx_sdu_size += skb->len;
+
+ /*
+ * If SAR is disabled, or user has requested no reassembly
+ * of received fragments then we just deliver them
+ * immediately. This can be requested by clients that
+ * implements byte streams without any message boundaries
+ */
+ if (self->rx_max_sdu_size == TTP_SAR_DISABLE) {
+ irttp_do_data_indication(self, skb);
+ self->rx_sdu_size = 0;
+
+ continue;
+ }
+
+ /* Check if this is a fragment, and not the last fragment */
+ if (more) {
+ /*
+ * Queue the fragment if we still are within the
+ * limits of the maximum size of the rx_sdu
+ */
+ if (self->rx_sdu_size <= self->rx_max_sdu_size) {
+ pr_debug("%s(), queueing frag\n",
+ __func__);
+ skb_queue_tail(&self->rx_fragments, skb);
+ } else {
+ /* Free the part of the SDU that is too big */
+ dev_kfree_skb(skb);
+ }
+ continue;
+ }
+ /*
+ * This is the last fragment, so time to reassemble!
+ */
+ if ((self->rx_sdu_size <= self->rx_max_sdu_size) ||
+ (self->rx_max_sdu_size == TTP_SAR_UNBOUND)) {
+ /*
+ * A little optimizing. Only queue the fragment if
+ * there are other fragments. Since if this is the
+ * last and only fragment, there is no need to
+ * reassemble :-)
+ */
+ if (!skb_queue_empty(&self->rx_fragments)) {
+ skb_queue_tail(&self->rx_fragments,
+ skb);
+
+ skb = irttp_reassemble_skb(self);
+ }
+
+ /* Now we can deliver the reassembled skb */
+ irttp_do_data_indication(self, skb);
+ } else {
+ pr_debug("%s(), Truncated frame\n", __func__);
+
+ /* Free the part of the SDU that is too big */
+ dev_kfree_skb(skb);
+
+ /* Deliver only the valid but truncated part of SDU */
+ skb = irttp_reassemble_skb(self);
+
+ irttp_do_data_indication(self, skb);
+ }
+ self->rx_sdu_size = 0;
+ }
+
+ /*
+ * It's not trivial to keep track of how many credits are available
+ * by incrementing at each packet, because delivery may fail
+ * (irttp_do_data_indication() may requeue the frame) and because
+ * we need to take care of fragmentation.
+ * We want the other side to send up to initial_credit packets.
+ * We have some frames in our queues, and we have already allowed it
+ * to send remote_credit.
+ * No need to spinlock, write is atomic and self correcting...
+ * Jean II
+ */
+ self->avail_credit = (self->initial_credit -
+ (self->remote_credit +
+ skb_queue_len(&self->rx_queue) +
+ skb_queue_len(&self->rx_fragments)));
+
+ /* Do we have too much credits to send to peer ? */
+ if ((self->remote_credit <= TTP_RX_MIN_CREDIT) &&
+ (self->avail_credit > 0)) {
+ /* Send explicit credit frame */
+ irttp_give_credit(self);
+ /* Note : do *NOT* check if tx_queue is non-empty, that
+ * will produce deadlocks. I repeat : send a credit frame
+ * even if we have something to send in our Tx queue.
+ * If we have credits, it means that our Tx queue is blocked.
+ *
+ * Let's suppose the peer can't keep up with our Tx. He will
+ * flow control us by not sending us any credits, and we
+ * will stop Tx and start accumulating credits here.
+ * Up to the point where the peer will stop its Tx queue,
+ * for lack of credits.
+ * Let's assume the peer application is single threaded.
+ * It will block on Tx and never consume any Rx buffer.
+ * Deadlock. Guaranteed. - Jean II
+ */
+ }
+
+ /* Reset lock */
+ self->rx_queue_lock = 0;
+}
+
+#ifdef CONFIG_PROC_FS
+struct irttp_iter_state {
+ int id;
+};
+
+static void *irttp_seq_start(struct seq_file *seq, loff_t *pos)
+{
+ struct irttp_iter_state *iter = seq->private;
+ struct tsap_cb *self;
+
+ /* Protect our access to the tsap list */
+ spin_lock_irq(&irttp->tsaps->hb_spinlock);
+ iter->id = 0;
+
+ for (self = (struct tsap_cb *) hashbin_get_first(irttp->tsaps);
+ self != NULL;
+ self = (struct tsap_cb *) hashbin_get_next(irttp->tsaps)) {
+ if (iter->id == *pos)
+ break;
+ ++iter->id;
+ }
+
+ return self;
+}
+
+static void *irttp_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+ struct irttp_iter_state *iter = seq->private;
+
+ ++*pos;
+ ++iter->id;
+ return (void *) hashbin_get_next(irttp->tsaps);
+}
+
+static void irttp_seq_stop(struct seq_file *seq, void *v)
+{
+ spin_unlock_irq(&irttp->tsaps->hb_spinlock);
+}
+
+static int irttp_seq_show(struct seq_file *seq, void *v)
+{
+ const struct irttp_iter_state *iter = seq->private;
+ const struct tsap_cb *self = v;
+
+ seq_printf(seq, "TSAP %d, ", iter->id);
+ seq_printf(seq, "stsap_sel: %02x, ",
+ self->stsap_sel);
+ seq_printf(seq, "dtsap_sel: %02x\n",
+ self->dtsap_sel);
+ seq_printf(seq, " connected: %s, ",
+ self->connected ? "TRUE" : "FALSE");
+ seq_printf(seq, "avail credit: %d, ",
+ self->avail_credit);
+ seq_printf(seq, "remote credit: %d, ",
+ self->remote_credit);
+ seq_printf(seq, "send credit: %d\n",
+ self->send_credit);
+ seq_printf(seq, " tx packets: %lu, ",
+ self->stats.tx_packets);
+ seq_printf(seq, "rx packets: %lu, ",
+ self->stats.rx_packets);
+ seq_printf(seq, "tx_queue len: %u ",
+ skb_queue_len(&self->tx_queue));
+ seq_printf(seq, "rx_queue len: %u\n",
+ skb_queue_len(&self->rx_queue));
+ seq_printf(seq, " tx_sdu_busy: %s, ",
+ self->tx_sdu_busy ? "TRUE" : "FALSE");
+ seq_printf(seq, "rx_sdu_busy: %s\n",
+ self->rx_sdu_busy ? "TRUE" : "FALSE");
+ seq_printf(seq, " max_seg_size: %u, ",
+ self->max_seg_size);
+ seq_printf(seq, "tx_max_sdu_size: %u, ",
+ self->tx_max_sdu_size);
+ seq_printf(seq, "rx_max_sdu_size: %u\n",
+ self->rx_max_sdu_size);
+
+ seq_printf(seq, " Used by (%s)\n\n",
+ self->notify.name);
+ return 0;
+}
+
+static const struct seq_operations irttp_seq_ops = {
+ .start = irttp_seq_start,
+ .next = irttp_seq_next,
+ .stop = irttp_seq_stop,
+ .show = irttp_seq_show,
+};
+
+static int irttp_seq_open(struct inode *inode, struct file *file)
+{
+ return seq_open_private(file, &irttp_seq_ops,
+ sizeof(struct irttp_iter_state));
+}
+
+const struct file_operations irttp_seq_fops = {
+ .owner = THIS_MODULE,
+ .open = irttp_seq_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release_private,
+};
+
+#endif /* PROC_FS */