Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / net / irda / irlap_frame.c
diff --git a/kernel/net/irda/irlap_frame.c b/kernel/net/irda/irlap_frame.c
new file mode 100644 (file)
index 0000000..b936b12
--- /dev/null
@@ -0,0 +1,1411 @@
+/*********************************************************************
+ *
+ * Filename:      irlap_frame.c
+ * Version:       1.0
+ * Description:   Build and transmit IrLAP frames
+ * Status:        Stable
+ * Author:        Dag Brattli <dagb@cs.uit.no>
+ * Created at:    Tue Aug 19 10:27:26 1997
+ * Modified at:   Wed Jan  5 08:59:04 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/if.h>
+#include <linux/if_ether.h>
+#include <linux/netdevice.h>
+#include <linux/irda.h>
+#include <linux/slab.h>
+
+#include <net/pkt_sched.h>
+#include <net/sock.h>
+
+#include <asm/byteorder.h>
+
+#include <net/irda/irda.h>
+#include <net/irda/irda_device.h>
+#include <net/irda/irlap.h>
+#include <net/irda/wrapper.h>
+#include <net/irda/timer.h>
+#include <net/irda/irlap_frame.h>
+#include <net/irda/qos.h>
+
+static void irlap_send_i_frame(struct irlap_cb *self, struct sk_buff *skb,
+                              int command);
+
+/*
+ * Function irlap_insert_info (self, skb)
+ *
+ *    Insert minimum turnaround time and speed information into the skb. We
+ *    need to do this since it's per packet relevant information. Safe to
+ *    have this function inlined since it's only called from one place
+ */
+static inline void irlap_insert_info(struct irlap_cb *self,
+                                    struct sk_buff *skb)
+{
+       struct irda_skb_cb *cb = (struct irda_skb_cb *) skb->cb;
+
+       /*
+        * Insert MTT (min. turn time) and speed into skb, so that the
+        * device driver knows which settings to use
+        */
+       cb->magic = LAP_MAGIC;
+       cb->mtt = self->mtt_required;
+       cb->next_speed = self->speed;
+
+       /* Reset */
+       self->mtt_required = 0;
+
+       /*
+        * Delay equals negotiated BOFs count, plus the number of BOFs to
+        * force the negotiated minimum turnaround time
+        */
+       cb->xbofs = self->bofs_count;
+       cb->next_xbofs = self->next_bofs;
+       cb->xbofs_delay = self->xbofs_delay;
+
+       /* Reset XBOF's delay (used only for getting min turn time) */
+       self->xbofs_delay = 0;
+       /* Put the correct xbofs value for the next packet */
+       self->bofs_count = self->next_bofs;
+}
+
+/*
+ * Function irlap_queue_xmit (self, skb)
+ *
+ *    A little wrapper for dev_queue_xmit, so we can insert some common
+ *    code into it.
+ */
+void irlap_queue_xmit(struct irlap_cb *self, struct sk_buff *skb)
+{
+       /* Some common init stuff */
+       skb->dev = self->netdev;
+       skb_reset_mac_header(skb);
+       skb_reset_network_header(skb);
+       skb_reset_transport_header(skb);
+       skb->protocol = htons(ETH_P_IRDA);
+       skb->priority = TC_PRIO_BESTEFFORT;
+
+       irlap_insert_info(self, skb);
+
+       if (unlikely(self->mode & IRDA_MODE_MONITOR)) {
+               pr_debug("%s(): %s is in monitor mode\n", __func__,
+                        self->netdev->name);
+               dev_kfree_skb(skb);
+               return;
+       }
+
+       dev_queue_xmit(skb);
+}
+
+/*
+ * Function irlap_send_snrm_cmd (void)
+ *
+ *    Transmits a connect SNRM command frame
+ */
+void irlap_send_snrm_frame(struct irlap_cb *self, struct qos_info *qos)
+{
+       struct sk_buff *tx_skb;
+       struct snrm_frame *frame;
+       int ret;
+
+       IRDA_ASSERT(self != NULL, return;);
+       IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
+
+       /* Allocate frame */
+       tx_skb = alloc_skb(sizeof(struct snrm_frame) +
+                          IRLAP_NEGOCIATION_PARAMS_LEN,
+                          GFP_ATOMIC);
+       if (!tx_skb)
+               return;
+
+       frame = (struct snrm_frame *) skb_put(tx_skb, 2);
+
+       /* Insert connection address field */
+       if (qos)
+               frame->caddr = CMD_FRAME | CBROADCAST;
+       else
+               frame->caddr = CMD_FRAME | self->caddr;
+
+       /* Insert control field */
+       frame->control = SNRM_CMD | PF_BIT;
+
+       /*
+        *  If we are establishing a connection then insert QoS parameters
+        */
+       if (qos) {
+               skb_put(tx_skb, 9); /* 25 left */
+               frame->saddr = cpu_to_le32(self->saddr);
+               frame->daddr = cpu_to_le32(self->daddr);
+
+               frame->ncaddr = self->caddr;
+
+               ret = irlap_insert_qos_negotiation_params(self, tx_skb);
+               if (ret < 0) {
+                       dev_kfree_skb(tx_skb);
+                       return;
+               }
+       }
+       irlap_queue_xmit(self, tx_skb);
+}
+
+/*
+ * Function irlap_recv_snrm_cmd (skb, info)
+ *
+ *    Received SNRM (Set Normal Response Mode) command frame
+ *
+ */
+static void irlap_recv_snrm_cmd(struct irlap_cb *self, struct sk_buff *skb,
+                               struct irlap_info *info)
+{
+       struct snrm_frame *frame;
+
+       if (pskb_may_pull(skb,sizeof(struct snrm_frame))) {
+               frame = (struct snrm_frame *) skb->data;
+
+               /* Copy the new connection address ignoring the C/R bit */
+               info->caddr = frame->ncaddr & 0xFE;
+
+               /* Check if the new connection address is valid */
+               if ((info->caddr == 0x00) || (info->caddr == 0xfe)) {
+                       pr_debug("%s(), invalid connection address!\n",
+                                __func__);
+                       return;
+               }
+
+               /* Copy peer device address */
+               info->daddr = le32_to_cpu(frame->saddr);
+               info->saddr = le32_to_cpu(frame->daddr);
+
+               /* Only accept if addressed directly to us */
+               if (info->saddr != self->saddr) {
+                       pr_debug("%s(), not addressed to us!\n",
+                                __func__);
+                       return;
+               }
+               irlap_do_event(self, RECV_SNRM_CMD, skb, info);
+       } else {
+               /* Signal that this SNRM frame does not contain and I-field */
+               irlap_do_event(self, RECV_SNRM_CMD, skb, NULL);
+       }
+}
+
+/*
+ * Function irlap_send_ua_response_frame (qos)
+ *
+ *    Send UA (Unnumbered Acknowledgement) frame
+ *
+ */
+void irlap_send_ua_response_frame(struct irlap_cb *self, struct qos_info *qos)
+{
+       struct sk_buff *tx_skb;
+       struct ua_frame *frame;
+       int ret;
+
+       pr_debug("%s() <%ld>\n", __func__, jiffies);
+
+       IRDA_ASSERT(self != NULL, return;);
+       IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
+
+       /* Allocate frame */
+       tx_skb = alloc_skb(sizeof(struct ua_frame) +
+                          IRLAP_NEGOCIATION_PARAMS_LEN,
+                          GFP_ATOMIC);
+       if (!tx_skb)
+               return;
+
+       frame = (struct ua_frame *) skb_put(tx_skb, 10);
+
+       /* Build UA response */
+       frame->caddr = self->caddr;
+       frame->control = UA_RSP | PF_BIT;
+
+       frame->saddr = cpu_to_le32(self->saddr);
+       frame->daddr = cpu_to_le32(self->daddr);
+
+       /* Should we send QoS negotiation parameters? */
+       if (qos) {
+               ret = irlap_insert_qos_negotiation_params(self, tx_skb);
+               if (ret < 0) {
+                       dev_kfree_skb(tx_skb);
+                       return;
+               }
+       }
+
+       irlap_queue_xmit(self, tx_skb);
+}
+
+
+/*
+ * Function irlap_send_dm_frame (void)
+ *
+ *    Send disconnected mode (DM) frame
+ *
+ */
+void irlap_send_dm_frame( struct irlap_cb *self)
+{
+       struct sk_buff *tx_skb = NULL;
+       struct dm_frame *frame;
+
+       IRDA_ASSERT(self != NULL, return;);
+       IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
+
+       tx_skb = alloc_skb(sizeof(struct dm_frame), GFP_ATOMIC);
+       if (!tx_skb)
+               return;
+
+       frame = (struct dm_frame *)skb_put(tx_skb, 2);
+
+       if (self->state == LAP_NDM)
+               frame->caddr = CBROADCAST;
+       else
+               frame->caddr = self->caddr;
+
+       frame->control = DM_RSP | PF_BIT;
+
+       irlap_queue_xmit(self, tx_skb);
+}
+
+/*
+ * Function irlap_send_disc_frame (void)
+ *
+ *    Send disconnect (DISC) frame
+ *
+ */
+void irlap_send_disc_frame(struct irlap_cb *self)
+{
+       struct sk_buff *tx_skb = NULL;
+       struct disc_frame *frame;
+
+       IRDA_ASSERT(self != NULL, return;);
+       IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
+
+       tx_skb = alloc_skb(sizeof(struct disc_frame), GFP_ATOMIC);
+       if (!tx_skb)
+               return;
+
+       frame = (struct disc_frame *)skb_put(tx_skb, 2);
+
+       frame->caddr = self->caddr | CMD_FRAME;
+       frame->control = DISC_CMD | PF_BIT;
+
+       irlap_queue_xmit(self, tx_skb);
+}
+
+/*
+ * Function irlap_send_discovery_xid_frame (S, s, command)
+ *
+ *    Build and transmit a XID (eXchange station IDentifier) discovery
+ *    frame.
+ */
+void irlap_send_discovery_xid_frame(struct irlap_cb *self, int S, __u8 s,
+                                   __u8 command, discovery_t *discovery)
+{
+       struct sk_buff *tx_skb = NULL;
+       struct xid_frame *frame;
+       __u32 bcast = BROADCAST;
+       __u8 *info;
+
+       pr_debug("%s(), s=%d, S=%d, command=%d\n", __func__,
+                s, S, command);
+
+       IRDA_ASSERT(self != NULL, return;);
+       IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
+       IRDA_ASSERT(discovery != NULL, return;);
+
+       tx_skb = alloc_skb(sizeof(struct xid_frame) + IRLAP_DISCOVERY_INFO_LEN,
+                          GFP_ATOMIC);
+       if (!tx_skb)
+               return;
+
+       skb_put(tx_skb, 14);
+       frame = (struct xid_frame *) tx_skb->data;
+
+       if (command) {
+               frame->caddr = CBROADCAST | CMD_FRAME;
+               frame->control =  XID_CMD | PF_BIT;
+       } else {
+               frame->caddr = CBROADCAST;
+               frame->control =  XID_RSP | PF_BIT;
+       }
+       frame->ident = XID_FORMAT;
+
+       frame->saddr = cpu_to_le32(self->saddr);
+
+       if (command)
+               frame->daddr = cpu_to_le32(bcast);
+       else
+               frame->daddr = cpu_to_le32(discovery->data.daddr);
+
+       switch (S) {
+       case 1:
+               frame->flags = 0x00;
+               break;
+       case 6:
+               frame->flags = 0x01;
+               break;
+       case 8:
+               frame->flags = 0x02;
+               break;
+       case 16:
+               frame->flags = 0x03;
+               break;
+       default:
+               frame->flags = 0x02;
+               break;
+       }
+
+       frame->slotnr = s;
+       frame->version = 0x00;
+
+       /*
+        *  Provide info for final slot only in commands, and for all
+        *  responses. Send the second byte of the hint only if the
+        *  EXTENSION bit is set in the first byte.
+        */
+       if (!command || (frame->slotnr == 0xff)) {
+               int len;
+
+               if (discovery->data.hints[0] & HINT_EXTENSION) {
+                       info = skb_put(tx_skb, 2);
+                       info[0] = discovery->data.hints[0];
+                       info[1] = discovery->data.hints[1];
+               } else {
+                       info = skb_put(tx_skb, 1);
+                       info[0] = discovery->data.hints[0];
+               }
+               info = skb_put(tx_skb, 1);
+               info[0] = discovery->data.charset;
+
+               len = IRDA_MIN(discovery->name_len, skb_tailroom(tx_skb));
+               info = skb_put(tx_skb, len);
+               memcpy(info, discovery->data.info, len);
+       }
+       irlap_queue_xmit(self, tx_skb);
+}
+
+/*
+ * Function irlap_recv_discovery_xid_rsp (skb, info)
+ *
+ *    Received a XID discovery response
+ *
+ */
+static void irlap_recv_discovery_xid_rsp(struct irlap_cb *self,
+                                        struct sk_buff *skb,
+                                        struct irlap_info *info)
+{
+       struct xid_frame *xid;
+       discovery_t *discovery = NULL;
+       __u8 *discovery_info;
+       char *text;
+
+       IRDA_ASSERT(self != NULL, return;);
+       IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
+
+       if (!pskb_may_pull(skb, sizeof(struct xid_frame))) {
+               net_err_ratelimited("%s: frame too short!\n", __func__);
+               return;
+       }
+
+       xid = (struct xid_frame *) skb->data;
+
+       info->daddr = le32_to_cpu(xid->saddr);
+       info->saddr = le32_to_cpu(xid->daddr);
+
+       /* Make sure frame is addressed to us */
+       if ((info->saddr != self->saddr) && (info->saddr != BROADCAST)) {
+               pr_debug("%s(), frame is not addressed to us!\n",
+                        __func__);
+               return;
+       }
+
+       if ((discovery = kzalloc(sizeof(discovery_t), GFP_ATOMIC)) == NULL) {
+               net_warn_ratelimited("%s: kmalloc failed!\n", __func__);
+               return;
+       }
+
+       discovery->data.daddr = info->daddr;
+       discovery->data.saddr = self->saddr;
+       discovery->timestamp = jiffies;
+
+       pr_debug("%s(), daddr=%08x\n", __func__,
+                discovery->data.daddr);
+
+       discovery_info = skb_pull(skb, sizeof(struct xid_frame));
+
+       /* Get info returned from peer */
+       discovery->data.hints[0] = discovery_info[0];
+       if (discovery_info[0] & HINT_EXTENSION) {
+               pr_debug("EXTENSION\n");
+               discovery->data.hints[1] = discovery_info[1];
+               discovery->data.charset = discovery_info[2];
+               text = (char *) &discovery_info[3];
+       } else {
+               discovery->data.hints[1] = 0;
+               discovery->data.charset = discovery_info[1];
+               text = (char *) &discovery_info[2];
+       }
+       /*
+        *  Terminate info string, should be safe since this is where the
+        *  FCS bytes resides.
+        */
+       skb->data[skb->len] = '\0';
+       strncpy(discovery->data.info, text, NICKNAME_MAX_LEN);
+       discovery->name_len = strlen(discovery->data.info);
+
+       info->discovery = discovery;
+
+       irlap_do_event(self, RECV_DISCOVERY_XID_RSP, skb, info);
+}
+
+/*
+ * Function irlap_recv_discovery_xid_cmd (skb, info)
+ *
+ *    Received a XID discovery command
+ *
+ */
+static void irlap_recv_discovery_xid_cmd(struct irlap_cb *self,
+                                        struct sk_buff *skb,
+                                        struct irlap_info *info)
+{
+       struct xid_frame *xid;
+       discovery_t *discovery = NULL;
+       __u8 *discovery_info;
+       char *text;
+
+       if (!pskb_may_pull(skb, sizeof(struct xid_frame))) {
+               net_err_ratelimited("%s: frame too short!\n", __func__);
+               return;
+       }
+
+       xid = (struct xid_frame *) skb->data;
+
+       info->daddr = le32_to_cpu(xid->saddr);
+       info->saddr = le32_to_cpu(xid->daddr);
+
+       /* Make sure frame is addressed to us */
+       if ((info->saddr != self->saddr) && (info->saddr != BROADCAST)) {
+               pr_debug("%s(), frame is not addressed to us!\n",
+                        __func__);
+               return;
+       }
+
+       switch (xid->flags & 0x03) {
+       case 0x00:
+               info->S = 1;
+               break;
+       case 0x01:
+               info->S = 6;
+               break;
+       case 0x02:
+               info->S = 8;
+               break;
+       case 0x03:
+               info->S = 16;
+               break;
+       default:
+               /* Error!! */
+               return;
+       }
+       info->s = xid->slotnr;
+
+       discovery_info = skb_pull(skb, sizeof(struct xid_frame));
+
+       /*
+        *  Check if last frame
+        */
+       if (info->s == 0xff) {
+               /* Check if things are sane at this point... */
+               if((discovery_info == NULL) ||
+                  !pskb_may_pull(skb, 3)) {
+                       net_err_ratelimited("%s: discovery frame too short!\n",
+                                           __func__);
+                       return;
+               }
+
+               /*
+                *  We now have some discovery info to deliver!
+                */
+               discovery = kzalloc(sizeof(discovery_t), GFP_ATOMIC);
+               if (!discovery)
+                       return;
+
+               discovery->data.daddr = info->daddr;
+               discovery->data.saddr = self->saddr;
+               discovery->timestamp = jiffies;
+
+               discovery->data.hints[0] = discovery_info[0];
+               if (discovery_info[0] & HINT_EXTENSION) {
+                       discovery->data.hints[1] = discovery_info[1];
+                       discovery->data.charset = discovery_info[2];
+                       text = (char *) &discovery_info[3];
+               } else {
+                       discovery->data.hints[1] = 0;
+                       discovery->data.charset = discovery_info[1];
+                       text = (char *) &discovery_info[2];
+               }
+               /*
+                *  Terminate string, should be safe since this is where the
+                *  FCS bytes resides.
+                */
+               skb->data[skb->len] = '\0';
+               strncpy(discovery->data.info, text, NICKNAME_MAX_LEN);
+               discovery->name_len = strlen(discovery->data.info);
+
+               info->discovery = discovery;
+       } else
+               info->discovery = NULL;
+
+       irlap_do_event(self, RECV_DISCOVERY_XID_CMD, skb, info);
+}
+
+/*
+ * Function irlap_send_rr_frame (self, command)
+ *
+ *    Build and transmit RR (Receive Ready) frame. Notice that it is currently
+ *    only possible to send RR frames with the poll bit set.
+ */
+void irlap_send_rr_frame(struct irlap_cb *self, int command)
+{
+       struct sk_buff *tx_skb;
+       struct rr_frame *frame;
+
+       tx_skb = alloc_skb(sizeof(struct rr_frame), GFP_ATOMIC);
+       if (!tx_skb)
+               return;
+
+       frame = (struct rr_frame *)skb_put(tx_skb, 2);
+
+       frame->caddr = self->caddr;
+       frame->caddr |= (command) ? CMD_FRAME : 0;
+
+       frame->control = RR | PF_BIT | (self->vr << 5);
+
+       irlap_queue_xmit(self, tx_skb);
+}
+
+/*
+ * Function irlap_send_rd_frame (self)
+ *
+ *    Request disconnect. Used by a secondary station to request the
+ *    disconnection of the link.
+ */
+void irlap_send_rd_frame(struct irlap_cb *self)
+{
+       struct sk_buff *tx_skb;
+       struct rd_frame *frame;
+
+       tx_skb = alloc_skb(sizeof(struct rd_frame), GFP_ATOMIC);
+       if (!tx_skb)
+               return;
+
+       frame = (struct rd_frame *)skb_put(tx_skb, 2);
+
+       frame->caddr = self->caddr;
+       frame->control = RD_RSP | PF_BIT;
+
+       irlap_queue_xmit(self, tx_skb);
+}
+
+/*
+ * Function irlap_recv_rr_frame (skb, info)
+ *
+ *    Received RR (Receive Ready) frame from peer station, no harm in
+ *    making it inline since its called only from one single place
+ *    (irlap_driver_rcv).
+ */
+static inline void irlap_recv_rr_frame(struct irlap_cb *self,
+                                      struct sk_buff *skb,
+                                      struct irlap_info *info, int command)
+{
+       info->nr = skb->data[1] >> 5;
+
+       /* Check if this is a command or a response frame */
+       if (command)
+               irlap_do_event(self, RECV_RR_CMD, skb, info);
+       else
+               irlap_do_event(self, RECV_RR_RSP, skb, info);
+}
+
+/*
+ * Function irlap_recv_rnr_frame (self, skb, info)
+ *
+ *    Received RNR (Receive Not Ready) frame from peer station
+ *
+ */
+static void irlap_recv_rnr_frame(struct irlap_cb *self, struct sk_buff *skb,
+                                struct irlap_info *info, int command)
+{
+       info->nr = skb->data[1] >> 5;
+
+       pr_debug("%s(), nr=%d, %ld\n", __func__, info->nr, jiffies);
+
+       if (command)
+               irlap_do_event(self, RECV_RNR_CMD, skb, info);
+       else
+               irlap_do_event(self, RECV_RNR_RSP, skb, info);
+}
+
+static void irlap_recv_rej_frame(struct irlap_cb *self, struct sk_buff *skb,
+                                struct irlap_info *info, int command)
+{
+       info->nr = skb->data[1] >> 5;
+
+       /* Check if this is a command or a response frame */
+       if (command)
+               irlap_do_event(self, RECV_REJ_CMD, skb, info);
+       else
+               irlap_do_event(self, RECV_REJ_RSP, skb, info);
+}
+
+static void irlap_recv_srej_frame(struct irlap_cb *self, struct sk_buff *skb,
+                                 struct irlap_info *info, int command)
+{
+       info->nr = skb->data[1] >> 5;
+
+       /* Check if this is a command or a response frame */
+       if (command)
+               irlap_do_event(self, RECV_SREJ_CMD, skb, info);
+       else
+               irlap_do_event(self, RECV_SREJ_RSP, skb, info);
+}
+
+static void irlap_recv_disc_frame(struct irlap_cb *self, struct sk_buff *skb,
+                                 struct irlap_info *info, int command)
+{
+       /* Check if this is a command or a response frame */
+       if (command)
+               irlap_do_event(self, RECV_DISC_CMD, skb, info);
+       else
+               irlap_do_event(self, RECV_RD_RSP, skb, info);
+}
+
+/*
+ * Function irlap_recv_ua_frame (skb, frame)
+ *
+ *    Received UA (Unnumbered Acknowledgement) frame
+ *
+ */
+static inline void irlap_recv_ua_frame(struct irlap_cb *self,
+                                      struct sk_buff *skb,
+                                      struct irlap_info *info)
+{
+       irlap_do_event(self, RECV_UA_RSP, skb, info);
+}
+
+/*
+ * Function irlap_send_data_primary(self, skb)
+ *
+ *    Send I-frames as the primary station but without the poll bit set
+ *
+ */
+void irlap_send_data_primary(struct irlap_cb *self, struct sk_buff *skb)
+{
+       struct sk_buff *tx_skb;
+
+       if (skb->data[1] == I_FRAME) {
+
+               /*
+                *  Insert frame sequence number (Vs) in control field before
+                *  inserting into transmit window queue.
+                */
+               skb->data[1] = I_FRAME | (self->vs << 1);
+
+               /*
+                *  Insert frame in store, in case of retransmissions
+                *  Increase skb reference count, see irlap_do_event()
+                */
+               skb_get(skb);
+               skb_queue_tail(&self->wx_list, skb);
+
+               /* Copy buffer */
+               tx_skb = skb_clone(skb, GFP_ATOMIC);
+               if (tx_skb == NULL) {
+                       return;
+               }
+
+               self->vs = (self->vs + 1) % 8;
+               self->ack_required = FALSE;
+               self->window -= 1;
+
+               irlap_send_i_frame( self, tx_skb, CMD_FRAME);
+       } else {
+               pr_debug("%s(), sending unreliable frame\n", __func__);
+               irlap_send_ui_frame(self, skb_get(skb), self->caddr, CMD_FRAME);
+               self->window -= 1;
+       }
+}
+/*
+ * Function irlap_send_data_primary_poll (self, skb)
+ *
+ *    Send I(nformation) frame as primary with poll bit set
+ */
+void irlap_send_data_primary_poll(struct irlap_cb *self, struct sk_buff *skb)
+{
+       struct sk_buff *tx_skb;
+       int transmission_time;
+
+       /* Stop P timer */
+       del_timer(&self->poll_timer);
+
+       /* Is this reliable or unreliable data? */
+       if (skb->data[1] == I_FRAME) {
+
+               /*
+                *  Insert frame sequence number (Vs) in control field before
+                *  inserting into transmit window queue.
+                */
+               skb->data[1] = I_FRAME | (self->vs << 1);
+
+               /*
+                *  Insert frame in store, in case of retransmissions
+                *  Increase skb reference count, see irlap_do_event()
+                */
+               skb_get(skb);
+               skb_queue_tail(&self->wx_list, skb);
+
+               /* Copy buffer */
+               tx_skb = skb_clone(skb, GFP_ATOMIC);
+               if (tx_skb == NULL) {
+                       return;
+               }
+
+               /*
+                *  Set poll bit if necessary. We do this to the copied
+                *  skb, since retransmitted need to set or clear the poll
+                *  bit depending on when they are sent.
+                */
+               tx_skb->data[1] |= PF_BIT;
+
+               self->vs = (self->vs + 1) % 8;
+               self->ack_required = FALSE;
+
+               irlap_next_state(self, LAP_NRM_P);
+               irlap_send_i_frame(self, tx_skb, CMD_FRAME);
+       } else {
+               pr_debug("%s(), sending unreliable frame\n", __func__);
+
+               if (self->ack_required) {
+                       irlap_send_ui_frame(self, skb_get(skb), self->caddr, CMD_FRAME);
+                       irlap_next_state(self, LAP_NRM_P);
+                       irlap_send_rr_frame(self, CMD_FRAME);
+                       self->ack_required = FALSE;
+               } else {
+                       skb->data[1] |= PF_BIT;
+                       irlap_next_state(self, LAP_NRM_P);
+                       irlap_send_ui_frame(self, skb_get(skb), self->caddr, CMD_FRAME);
+               }
+       }
+
+       /* How much time we took for transmission of all frames.
+        * We don't know, so let assume we used the full window. Jean II */
+       transmission_time = self->final_timeout;
+
+       /* Reset parameter so that we can fill next window */
+       self->window = self->window_size;
+
+#ifdef CONFIG_IRDA_DYNAMIC_WINDOW
+       /* Remove what we have not used. Just do a prorata of the
+        * bytes left in window to window capacity.
+        * See max_line_capacities[][] in qos.c for details. Jean II */
+       transmission_time -= (self->final_timeout * self->bytes_left
+                             / self->line_capacity);
+       pr_debug("%s() adjusting transmission_time : ft=%d, bl=%d, lc=%d -> tt=%d\n",
+                __func__, self->final_timeout, self->bytes_left,
+                self->line_capacity, transmission_time);
+
+       /* We are allowed to transmit a maximum number of bytes again. */
+       self->bytes_left = self->line_capacity;
+#endif /* CONFIG_IRDA_DYNAMIC_WINDOW */
+
+       /*
+        * The network layer has a intermediate buffer between IrLAP
+        * and the IrDA driver which can contain 8 frames. So, even
+        * though IrLAP is currently sending the *last* frame of the
+        * tx-window, the driver most likely has only just started
+        * sending the *first* frame of the same tx-window.
+        * I.e. we are always at the very beginning of or Tx window.
+        * Now, we are supposed to set the final timer from the end
+        * of our tx-window to let the other peer reply. So, we need
+        * to add extra time to compensate for the fact that we
+        * are really at the start of tx-window, otherwise the final timer
+        * might expire before he can answer...
+        * Jean II
+        */
+       irlap_start_final_timer(self, self->final_timeout + transmission_time);
+
+       /*
+        * The clever amongst you might ask why we do this adjustement
+        * only here, and not in all the other cases in irlap_event.c.
+        * In all those other case, we only send a very short management
+        * frame (few bytes), so the adjustement would be lost in the
+        * noise...
+        * The exception of course is irlap_resend_rejected_frame().
+        * Jean II */
+}
+
+/*
+ * Function irlap_send_data_secondary_final (self, skb)
+ *
+ *    Send I(nformation) frame as secondary with final bit set
+ *
+ */
+void irlap_send_data_secondary_final(struct irlap_cb *self,
+                                    struct sk_buff *skb)
+{
+       struct sk_buff *tx_skb = NULL;
+
+       IRDA_ASSERT(self != NULL, return;);
+       IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
+       IRDA_ASSERT(skb != NULL, return;);
+
+       /* Is this reliable or unreliable data? */
+       if (skb->data[1] == I_FRAME) {
+
+               /*
+                *  Insert frame sequence number (Vs) in control field before
+                *  inserting into transmit window queue.
+                */
+               skb->data[1] = I_FRAME | (self->vs << 1);
+
+               /*
+                *  Insert frame in store, in case of retransmissions
+                *  Increase skb reference count, see irlap_do_event()
+                */
+               skb_get(skb);
+               skb_queue_tail(&self->wx_list, skb);
+
+               tx_skb = skb_clone(skb, GFP_ATOMIC);
+               if (tx_skb == NULL) {
+                       return;
+               }
+
+               tx_skb->data[1] |= PF_BIT;
+
+               self->vs = (self->vs + 1) % 8;
+               self->ack_required = FALSE;
+
+               irlap_send_i_frame(self, tx_skb, RSP_FRAME);
+       } else {
+               if (self->ack_required) {
+                       irlap_send_ui_frame(self, skb_get(skb), self->caddr, RSP_FRAME);
+                       irlap_send_rr_frame(self, RSP_FRAME);
+                       self->ack_required = FALSE;
+               } else {
+                       skb->data[1] |= PF_BIT;
+                       irlap_send_ui_frame(self, skb_get(skb), self->caddr, RSP_FRAME);
+               }
+       }
+
+       self->window = self->window_size;
+#ifdef CONFIG_IRDA_DYNAMIC_WINDOW
+       /* We are allowed to transmit a maximum number of bytes again. */
+       self->bytes_left = self->line_capacity;
+#endif /* CONFIG_IRDA_DYNAMIC_WINDOW */
+
+       irlap_start_wd_timer(self, self->wd_timeout);
+}
+
+/*
+ * Function irlap_send_data_secondary (self, skb)
+ *
+ *    Send I(nformation) frame as secondary without final bit set
+ *
+ */
+void irlap_send_data_secondary(struct irlap_cb *self, struct sk_buff *skb)
+{
+       struct sk_buff *tx_skb = NULL;
+
+       /* Is this reliable or unreliable data? */
+       if (skb->data[1] == I_FRAME) {
+
+               /*
+                *  Insert frame sequence number (Vs) in control field before
+                *  inserting into transmit window queue.
+                */
+               skb->data[1] = I_FRAME | (self->vs << 1);
+
+               /*
+                *  Insert frame in store, in case of retransmissions
+                *  Increase skb reference count, see irlap_do_event()
+                */
+               skb_get(skb);
+               skb_queue_tail(&self->wx_list, skb);
+
+               tx_skb = skb_clone(skb, GFP_ATOMIC);
+               if (tx_skb == NULL) {
+                       return;
+               }
+
+               self->vs = (self->vs + 1) % 8;
+               self->ack_required = FALSE;
+               self->window -= 1;
+
+               irlap_send_i_frame(self, tx_skb, RSP_FRAME);
+       } else {
+               irlap_send_ui_frame(self, skb_get(skb), self->caddr, RSP_FRAME);
+               self->window -= 1;
+       }
+}
+
+/*
+ * Function irlap_resend_rejected_frames (nr)
+ *
+ *    Resend frames which has not been acknowledged. Should be safe to
+ *    traverse the list without locking it since this function will only be
+ *    called from interrupt context (BH)
+ */
+void irlap_resend_rejected_frames(struct irlap_cb *self, int command)
+{
+       struct sk_buff *tx_skb;
+       struct sk_buff *skb;
+
+       IRDA_ASSERT(self != NULL, return;);
+       IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
+
+       /*  Resend unacknowledged frame(s) */
+       skb_queue_walk(&self->wx_list, skb) {
+               irlap_wait_min_turn_around(self, &self->qos_tx);
+
+               /* We copy the skb to be retransmitted since we will have to
+                * modify it. Cloning will confuse packet sniffers
+                */
+               /* tx_skb = skb_clone( skb, GFP_ATOMIC); */
+               tx_skb = skb_copy(skb, GFP_ATOMIC);
+               if (!tx_skb) {
+                       pr_debug("%s(), unable to copy\n", __func__);
+                       return;
+               }
+
+               /* Clear old Nr field + poll bit */
+               tx_skb->data[1] &= 0x0f;
+
+               /*
+                *  Set poll bit on the last frame retransmitted
+                */
+               if (skb_queue_is_last(&self->wx_list, skb))
+                       tx_skb->data[1] |= PF_BIT; /* Set p/f bit */
+               else
+                       tx_skb->data[1] &= ~PF_BIT; /* Clear p/f bit */
+
+               irlap_send_i_frame(self, tx_skb, command);
+       }
+#if 0 /* Not yet */
+       /*
+        *  We can now fill the window with additional data frames
+        */
+       while (!skb_queue_empty(&self->txq)) {
+
+               pr_debug("%s(), sending additional frames!\n", __func__);
+               if (self->window > 0) {
+                       skb = skb_dequeue( &self->txq);
+                       IRDA_ASSERT(skb != NULL, return;);
+
+                       /*
+                        *  If send window > 1 then send frame with pf
+                        *  bit cleared
+                        */
+                       if ((self->window > 1) &&
+                           !skb_queue_empty(&self->txq)) {
+                               irlap_send_data_primary(self, skb);
+                       } else {
+                               irlap_send_data_primary_poll(self, skb);
+                       }
+                       kfree_skb(skb);
+               }
+       }
+#endif
+}
+
+void irlap_resend_rejected_frame(struct irlap_cb *self, int command)
+{
+       struct sk_buff *tx_skb;
+       struct sk_buff *skb;
+
+       IRDA_ASSERT(self != NULL, return;);
+       IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
+
+       /*  Resend unacknowledged frame(s) */
+       skb = skb_peek(&self->wx_list);
+       if (skb != NULL) {
+               irlap_wait_min_turn_around(self, &self->qos_tx);
+
+               /* We copy the skb to be retransmitted since we will have to
+                * modify it. Cloning will confuse packet sniffers
+                */
+               /* tx_skb = skb_clone( skb, GFP_ATOMIC); */
+               tx_skb = skb_copy(skb, GFP_ATOMIC);
+               if (!tx_skb) {
+                       pr_debug("%s(), unable to copy\n", __func__);
+                       return;
+               }
+
+               /* Clear old Nr field + poll bit */
+               tx_skb->data[1] &= 0x0f;
+
+               /*  Set poll/final bit */
+               tx_skb->data[1] |= PF_BIT; /* Set p/f bit */
+
+               irlap_send_i_frame(self, tx_skb, command);
+       }
+}
+
+/*
+ * Function irlap_send_ui_frame (self, skb, command)
+ *
+ *    Contruct and transmit an Unnumbered Information (UI) frame
+ *
+ */
+void irlap_send_ui_frame(struct irlap_cb *self, struct sk_buff *skb,
+                        __u8 caddr, int command)
+{
+       IRDA_ASSERT(self != NULL, return;);
+       IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
+       IRDA_ASSERT(skb != NULL, return;);
+
+       /* Insert connection address */
+       skb->data[0] = caddr | ((command) ? CMD_FRAME : 0);
+
+       irlap_queue_xmit(self, skb);
+}
+
+/*
+ * Function irlap_send_i_frame (skb)
+ *
+ *    Contruct and transmit Information (I) frame
+ */
+static void irlap_send_i_frame(struct irlap_cb *self, struct sk_buff *skb,
+                              int command)
+{
+       /* Insert connection address */
+       skb->data[0] = self->caddr;
+       skb->data[0] |= (command) ? CMD_FRAME : 0;
+
+       /* Insert next to receive (Vr) */
+       skb->data[1] |= (self->vr << 5);  /* insert nr */
+
+       irlap_queue_xmit(self, skb);
+}
+
+/*
+ * Function irlap_recv_i_frame (skb, frame)
+ *
+ *    Receive and parse an I (Information) frame, no harm in making it inline
+ *    since it's called only from one single place (irlap_driver_rcv).
+ */
+static inline void irlap_recv_i_frame(struct irlap_cb *self,
+                                     struct sk_buff *skb,
+                                     struct irlap_info *info, int command)
+{
+       info->nr = skb->data[1] >> 5;          /* Next to receive */
+       info->pf = skb->data[1] & PF_BIT;      /* Final bit */
+       info->ns = (skb->data[1] >> 1) & 0x07; /* Next to send */
+
+       /* Check if this is a command or a response frame */
+       if (command)
+               irlap_do_event(self, RECV_I_CMD, skb, info);
+       else
+               irlap_do_event(self, RECV_I_RSP, skb, info);
+}
+
+/*
+ * Function irlap_recv_ui_frame (self, skb, info)
+ *
+ *    Receive and parse an Unnumbered Information (UI) frame
+ *
+ */
+static void irlap_recv_ui_frame(struct irlap_cb *self, struct sk_buff *skb,
+                               struct irlap_info *info)
+{
+       info->pf = skb->data[1] & PF_BIT;      /* Final bit */
+
+       irlap_do_event(self, RECV_UI_FRAME, skb, info);
+}
+
+/*
+ * Function irlap_recv_frmr_frame (skb, frame)
+ *
+ *    Received Frame Reject response.
+ *
+ */
+static void irlap_recv_frmr_frame(struct irlap_cb *self, struct sk_buff *skb,
+                                 struct irlap_info *info)
+{
+       __u8 *frame;
+       int w, x, y, z;
+
+       IRDA_ASSERT(self != NULL, return;);
+       IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
+       IRDA_ASSERT(skb != NULL, return;);
+       IRDA_ASSERT(info != NULL, return;);
+
+       if (!pskb_may_pull(skb, 4)) {
+               net_err_ratelimited("%s: frame too short!\n", __func__);
+               return;
+       }
+
+       frame = skb->data;
+
+       info->nr = frame[2] >> 5;          /* Next to receive */
+       info->pf = frame[2] & PF_BIT;      /* Final bit */
+       info->ns = (frame[2] >> 1) & 0x07; /* Next to send */
+
+       w = frame[3] & 0x01;
+       x = frame[3] & 0x02;
+       y = frame[3] & 0x04;
+       z = frame[3] & 0x08;
+
+       if (w) {
+               pr_debug("Rejected control field is undefined or not implemented\n");
+       }
+       if (x) {
+               pr_debug("Rejected control field was invalid because it contained a non permitted I field\n");
+       }
+       if (y) {
+               pr_debug("Received I field exceeded the maximum negotiated for the existing connection or exceeded the maximum this station supports if no connection exists\n");
+       }
+       if (z) {
+               pr_debug("Rejected control field control field contained an invalid Nr count\n");
+       }
+       irlap_do_event(self, RECV_FRMR_RSP, skb, info);
+}
+
+/*
+ * Function irlap_send_test_frame (self, daddr)
+ *
+ *    Send a test frame response
+ *
+ */
+void irlap_send_test_frame(struct irlap_cb *self, __u8 caddr, __u32 daddr,
+                          struct sk_buff *cmd)
+{
+       struct sk_buff *tx_skb;
+       struct test_frame *frame;
+       __u8 *info;
+
+       tx_skb = alloc_skb(cmd->len + sizeof(struct test_frame), GFP_ATOMIC);
+       if (!tx_skb)
+               return;
+
+       /* Broadcast frames must include saddr and daddr fields */
+       if (caddr == CBROADCAST) {
+               frame = (struct test_frame *)
+                       skb_put(tx_skb, sizeof(struct test_frame));
+
+               /* Insert the swapped addresses */
+               frame->saddr = cpu_to_le32(self->saddr);
+               frame->daddr = cpu_to_le32(daddr);
+       } else
+               frame = (struct test_frame *) skb_put(tx_skb, LAP_ADDR_HEADER + LAP_CTRL_HEADER);
+
+       frame->caddr = caddr;
+       frame->control = TEST_RSP | PF_BIT;
+
+       /* Copy info */
+       info = skb_put(tx_skb, cmd->len);
+       memcpy(info, cmd->data, cmd->len);
+
+       /* Return to sender */
+       irlap_wait_min_turn_around(self, &self->qos_tx);
+       irlap_queue_xmit(self, tx_skb);
+}
+
+/*
+ * Function irlap_recv_test_frame (self, skb)
+ *
+ *    Receive a test frame
+ *
+ */
+static void irlap_recv_test_frame(struct irlap_cb *self, struct sk_buff *skb,
+                                 struct irlap_info *info, int command)
+{
+       struct test_frame *frame;
+
+       if (!pskb_may_pull(skb, sizeof(*frame))) {
+               net_err_ratelimited("%s: frame too short!\n", __func__);
+               return;
+       }
+       frame = (struct test_frame *) skb->data;
+
+       /* Broadcast frames must carry saddr and daddr fields */
+       if (info->caddr == CBROADCAST) {
+               if (skb->len < sizeof(struct test_frame)) {
+                       pr_debug("%s() test frame too short!\n",
+                                __func__);
+                       return;
+               }
+
+               /* Read and swap addresses */
+               info->daddr = le32_to_cpu(frame->saddr);
+               info->saddr = le32_to_cpu(frame->daddr);
+
+               /* Make sure frame is addressed to us */
+               if ((info->saddr != self->saddr) &&
+                   (info->saddr != BROADCAST)) {
+                       return;
+               }
+       }
+
+       if (command)
+               irlap_do_event(self, RECV_TEST_CMD, skb, info);
+       else
+               irlap_do_event(self, RECV_TEST_RSP, skb, info);
+}
+
+/*
+ * Function irlap_driver_rcv (skb, netdev, ptype)
+ *
+ *    Called when a frame is received. Dispatches the right receive function
+ *    for processing of the frame.
+ *
+ * Note on skb management :
+ * After calling the higher layers of the IrDA stack, we always
+ * kfree() the skb, which drop the reference count (and potentially
+ * destroy it).
+ * If a higher layer of the stack want to keep the skb around (to put
+ * in a queue or pass it to the higher layer), it will need to use
+ * skb_get() to keep a reference on it. This is usually done at the
+ * LMP level in irlmp.c.
+ * Jean II
+ */
+int irlap_driver_rcv(struct sk_buff *skb, struct net_device *dev,
+                    struct packet_type *ptype, struct net_device *orig_dev)
+{
+       struct irlap_info info;
+       struct irlap_cb *self;
+       int command;
+       __u8 control;
+       int ret = -1;
+
+       if (!net_eq(dev_net(dev), &init_net))
+               goto out;
+
+       /* FIXME: should we get our own field? */
+       self = (struct irlap_cb *) dev->atalk_ptr;
+
+       /* If the net device is down, then IrLAP is gone! */
+       if (!self || self->magic != LAP_MAGIC)
+               goto err;
+
+       /* We are no longer an "old" protocol, so we need to handle
+        * share and non linear skbs. This should never happen, so
+        * we don't need to be clever about it. Jean II */
+       if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL) {
+               net_err_ratelimited("%s: can't clone shared skb!\n", __func__);
+               goto err;
+       }
+
+       /* Check if frame is large enough for parsing */
+       if (!pskb_may_pull(skb, 2)) {
+               net_err_ratelimited("%s: frame too short!\n", __func__);
+               goto err;
+       }
+
+       command    = skb->data[0] & CMD_FRAME;
+       info.caddr = skb->data[0] & CBROADCAST;
+
+       info.pf      = skb->data[1] &  PF_BIT;
+       info.control = skb->data[1] & ~PF_BIT; /* Mask away poll/final bit */
+
+       control = info.control;
+
+       /*  First we check if this frame has a valid connection address */
+       if ((info.caddr != self->caddr) && (info.caddr != CBROADCAST)) {
+               pr_debug("%s(), wrong connection address!\n",
+                        __func__);
+               goto out;
+       }
+       /*
+        *  Optimize for the common case and check if the frame is an
+        *  I(nformation) frame. Only I-frames have bit 0 set to 0
+        */
+       if (~control & 0x01) {
+               irlap_recv_i_frame(self, skb, &info, command);
+               goto out;
+       }
+       /*
+        *  We now check is the frame is an S(upervisory) frame. Only
+        *  S-frames have bit 0 set to 1 and bit 1 set to 0
+        */
+       if (~control & 0x02) {
+               /*
+                *  Received S(upervisory) frame, check which frame type it is
+                *  only the first nibble is of interest
+                */
+               switch (control & 0x0f) {
+               case RR:
+                       irlap_recv_rr_frame(self, skb, &info, command);
+                       break;
+               case RNR:
+                       irlap_recv_rnr_frame(self, skb, &info, command);
+                       break;
+               case REJ:
+                       irlap_recv_rej_frame(self, skb, &info, command);
+                       break;
+               case SREJ:
+                       irlap_recv_srej_frame(self, skb, &info, command);
+                       break;
+               default:
+                       net_warn_ratelimited("%s: Unknown S-frame %02x received!\n",
+                                            __func__, info.control);
+                       break;
+               }
+               goto out;
+       }
+       /*
+        *  This must be a C(ontrol) frame
+        */
+       switch (control) {
+       case XID_RSP:
+               irlap_recv_discovery_xid_rsp(self, skb, &info);
+               break;
+       case XID_CMD:
+               irlap_recv_discovery_xid_cmd(self, skb, &info);
+               break;
+       case SNRM_CMD:
+               irlap_recv_snrm_cmd(self, skb, &info);
+               break;
+       case DM_RSP:
+               irlap_do_event(self, RECV_DM_RSP, skb, &info);
+               break;
+       case DISC_CMD: /* And RD_RSP since they have the same value */
+               irlap_recv_disc_frame(self, skb, &info, command);
+               break;
+       case TEST_CMD:
+               irlap_recv_test_frame(self, skb, &info, command);
+               break;
+       case UA_RSP:
+               irlap_recv_ua_frame(self, skb, &info);
+               break;
+       case FRMR_RSP:
+               irlap_recv_frmr_frame(self, skb, &info);
+               break;
+       case UI_FRAME:
+               irlap_recv_ui_frame(self, skb, &info);
+               break;
+       default:
+               net_warn_ratelimited("%s: Unknown frame %02x received!\n",
+                                    __func__, info.control);
+               break;
+       }
+out:
+       ret = 0;
+err:
+       /* Always drop our reference on the skb */
+       dev_kfree_skb(skb);
+       return ret;
+}