| /********************************************************************* |
| * |
| * 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 pi_minor_info_t pi_minor_call_table[] = { |
| { NULL, 0 }, /* 0x00 */ |
| { irttp_param_max_sdu_size, PV_INTEGER | PV_BIG_ENDIAN } /* 0x01 */ |
| }; |
| static 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 */ |