+++ /dev/null
-/*********************************************************************
- *
- * 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 */
projects / linux-2.6-block.git / blobdiff