isdn: isdn_ppp: Use SKB list facilities instead of home-grown implementation.
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
David S. Miller
parent
8fc5387cb8
commit
38783e6713
@ -1533,8 +1533,10 @@ static int isdn_ppp_mp_bundle_array_init(void)
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int sz = ISDN_MAX_CHANNELS*sizeof(ippp_bundle);
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if( (isdn_ppp_bundle_arr = kzalloc(sz, GFP_KERNEL)) == NULL )
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return -ENOMEM;
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for( i = 0; i < ISDN_MAX_CHANNELS; i++ )
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for (i = 0; i < ISDN_MAX_CHANNELS; i++) {
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spin_lock_init(&isdn_ppp_bundle_arr[i].lock);
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skb_queue_head_init(&isdn_ppp_bundle_arr[i].frags);
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}
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return 0;
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}
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@ -1567,7 +1569,7 @@ static int isdn_ppp_mp_init( isdn_net_local * lp, ippp_bundle * add_to )
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if ((lp->netdev->pb = isdn_ppp_mp_bundle_alloc()) == NULL)
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return -ENOMEM;
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lp->next = lp->last = lp; /* nobody else in a queue */
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lp->netdev->pb->frags = NULL;
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skb_queue_head_init(&lp->netdev->pb->frags);
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lp->netdev->pb->frames = 0;
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lp->netdev->pb->seq = UINT_MAX;
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}
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@ -1579,23 +1581,24 @@ static int isdn_ppp_mp_init( isdn_net_local * lp, ippp_bundle * add_to )
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static u32 isdn_ppp_mp_get_seq( int short_seq,
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struct sk_buff * skb, u32 last_seq );
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static struct sk_buff * isdn_ppp_mp_discard( ippp_bundle * mp,
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struct sk_buff * from, struct sk_buff * to );
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static void isdn_ppp_mp_reassembly( isdn_net_dev * net_dev, isdn_net_local * lp,
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struct sk_buff * from, struct sk_buff * to );
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static void isdn_ppp_mp_free_skb( ippp_bundle * mp, struct sk_buff * skb );
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static void isdn_ppp_mp_discard(ippp_bundle *mp, struct sk_buff *from,
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struct sk_buff *to);
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static void isdn_ppp_mp_reassembly(isdn_net_dev *net_dev, isdn_net_local *lp,
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struct sk_buff *from, struct sk_buff *to,
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u32 lastseq);
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static void isdn_ppp_mp_free_skb(ippp_bundle *mp, struct sk_buff *skb);
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static void isdn_ppp_mp_print_recv_pkt( int slot, struct sk_buff * skb );
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static void isdn_ppp_mp_receive(isdn_net_dev * net_dev, isdn_net_local * lp,
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struct sk_buff *skb)
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{
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struct ippp_struct *is;
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isdn_net_local * lpq;
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ippp_bundle * mp;
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isdn_mppp_stats * stats;
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struct sk_buff * newfrag, * frag, * start, *nextf;
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struct sk_buff *newfrag, *frag, *start, *nextf;
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u32 newseq, minseq, thisseq;
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isdn_mppp_stats *stats;
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struct ippp_struct *is;
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unsigned long flags;
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isdn_net_local *lpq;
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ippp_bundle *mp;
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int slot;
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spin_lock_irqsave(&net_dev->pb->lock, flags);
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@ -1611,7 +1614,7 @@ static void isdn_ppp_mp_receive(isdn_net_dev * net_dev, isdn_net_local * lp,
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return;
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}
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is = ippp_table[slot];
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if( ++mp->frames > stats->max_queue_len )
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if (++mp->frames > stats->max_queue_len)
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stats->max_queue_len = mp->frames;
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if (is->debug & 0x8)
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@ -1620,11 +1623,10 @@ static void isdn_ppp_mp_receive(isdn_net_dev * net_dev, isdn_net_local * lp,
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newseq = isdn_ppp_mp_get_seq(is->mpppcfg & SC_IN_SHORT_SEQ,
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skb, is->last_link_seqno);
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/* if this packet seq # is less than last already processed one,
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* toss it right away, but check for sequence start case first
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*/
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if( mp->seq > MP_LONGSEQ_MAX && (newseq & MP_LONGSEQ_MAXBIT) ) {
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if (mp->seq > MP_LONGSEQ_MAX && (newseq & MP_LONGSEQ_MAXBIT)) {
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mp->seq = newseq; /* the first packet: required for
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* rfc1990 non-compliant clients --
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* prevents constant packet toss */
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@ -1655,22 +1657,31 @@ static void isdn_ppp_mp_receive(isdn_net_dev * net_dev, isdn_net_local * lp,
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* packets */
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newfrag = skb;
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/* if this new fragment is before the first one, then enqueue it now. */
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if ((frag = mp->frags) == NULL || MP_LT(newseq, MP_SEQ(frag))) {
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newfrag->next = frag;
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mp->frags = frag = newfrag;
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/* Insert new fragment into the proper sequence slot. */
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skb_queue_walk(&mp->frags, frag) {
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if (MP_SEQ(frag) == newseq) {
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isdn_ppp_mp_free_skb(mp, newfrag);
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newfrag = NULL;
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break;
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}
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if (MP_LT(newseq, MP_SEQ(frag))) {
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__skb_queue_before(&mp->frags, frag, newfrag);
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newfrag = NULL;
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break;
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}
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}
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if (newfrag)
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__skb_queue_tail(&mp->frags, newfrag);
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start = MP_FLAGS(frag) & MP_BEGIN_FRAG &&
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MP_SEQ(frag) == mp->seq ? frag : NULL;
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frag = skb_peek(&mp->frags);
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start = ((MP_FLAGS(frag) & MP_BEGIN_FRAG) &&
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(MP_SEQ(frag) == mp->seq)) ? frag : NULL;
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if (!start)
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goto check_overflow;
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/*
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* main fragment traversing loop
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/* main fragment traversing loop
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*
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* try to accomplish several tasks:
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* - insert new fragment into the proper sequence slot (once that's done
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* newfrag will be set to NULL)
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* - reassemble any complete fragment sequence (non-null 'start'
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* indicates there is a continguous sequence present)
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* - discard any incomplete sequences that are below minseq -- due
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@ -1679,70 +1690,45 @@ static void isdn_ppp_mp_receive(isdn_net_dev * net_dev, isdn_net_local * lp,
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* come to complete such sequence and it should be discarded
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*
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* loop completes when we accomplished the following tasks:
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* - new fragment is inserted in the proper sequence ('newfrag' is
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* set to NULL)
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* - we hit a gap in the sequence, so no reassembly/processing is
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* possible ('start' would be set to NULL)
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*
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* algorithm for this code is derived from code in the book
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* 'PPP Design And Debugging' by James Carlson (Addison-Wesley)
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*/
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while (start != NULL || newfrag != NULL) {
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skb_queue_walk_safe(&mp->frags, frag, nextf) {
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thisseq = MP_SEQ(frag);
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nextf = frag->next;
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/* drop any duplicate fragments */
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if (newfrag != NULL && thisseq == newseq) {
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isdn_ppp_mp_free_skb(mp, newfrag);
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newfrag = NULL;
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}
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/* insert new fragment before next element if possible. */
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if (newfrag != NULL && (nextf == NULL ||
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MP_LT(newseq, MP_SEQ(nextf)))) {
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newfrag->next = nextf;
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frag->next = nextf = newfrag;
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newfrag = NULL;
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}
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if (start != NULL) {
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/* check for misplaced start */
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if (start != frag && (MP_FLAGS(frag) & MP_BEGIN_FRAG)) {
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printk(KERN_WARNING"isdn_mppp(seq %d): new "
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"BEGIN flag with no prior END", thisseq);
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stats->seqerrs++;
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stats->frame_drops++;
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start = isdn_ppp_mp_discard(mp, start,frag);
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nextf = frag->next;
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}
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isdn_ppp_mp_discard(mp, start, frag);
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start = frag;
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} else if (MP_LE(thisseq, minseq)) {
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if (MP_FLAGS(frag) & MP_BEGIN_FRAG)
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start = frag;
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else {
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if (MP_FLAGS(frag) & MP_END_FRAG)
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stats->frame_drops++;
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if( mp->frags == frag )
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mp->frags = nextf;
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__skb_unlink(skb, &mp->frags);
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isdn_ppp_mp_free_skb(mp, frag);
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frag = nextf;
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continue;
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}
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}
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/* if start is non-null and we have end fragment, then
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* we have full reassembly sequence -- reassemble
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* and process packet now
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/* if we have end fragment, then we have full reassembly
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* sequence -- reassemble and process packet now
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*/
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if (start != NULL && (MP_FLAGS(frag) & MP_END_FRAG)) {
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if (MP_FLAGS(frag) & MP_END_FRAG) {
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minseq = mp->seq = (thisseq+1) & MP_LONGSEQ_MASK;
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/* Reassemble the packet then dispatch it */
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isdn_ppp_mp_reassembly(net_dev, lp, start, nextf);
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isdn_ppp_mp_reassembly(net_dev, lp, start, frag, thisseq);
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start = NULL;
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frag = NULL;
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mp->frags = nextf;
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}
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/* check if need to update start pointer: if we just
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@ -1754,25 +1740,24 @@ static void isdn_ppp_mp_receive(isdn_net_dev * net_dev, isdn_net_local * lp,
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* below low watermark and set start to the next frag or
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* clear start ptr.
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*/
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if (nextf != NULL &&
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if (nextf != (struct sk_buff *)&mp->frags &&
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((thisseq+1) & MP_LONGSEQ_MASK) == MP_SEQ(nextf)) {
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/* if we just reassembled and the next one is here,
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* then start another reassembly. */
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* then start another reassembly.
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*/
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if (frag == NULL) {
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if (MP_FLAGS(nextf) & MP_BEGIN_FRAG)
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start = nextf;
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else
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{
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else {
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printk(KERN_WARNING"isdn_mppp(seq %d):"
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" END flag with no following "
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"BEGIN", thisseq);
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stats->seqerrs++;
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}
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}
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} else {
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if ( nextf != NULL && frag != NULL &&
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if (nextf != (struct sk_buff *)&mp->frags &&
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frag != NULL &&
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MP_LT(thisseq, minseq)) {
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/* we've got a break in the sequence
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* and we not at the end yet
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@ -1782,41 +1767,39 @@ static void isdn_ppp_mp_receive(isdn_net_dev * net_dev, isdn_net_local * lp,
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* discard all the frames below low watermark
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* and start over */
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stats->frame_drops++;
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mp->frags = isdn_ppp_mp_discard(mp,start,nextf);
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isdn_ppp_mp_discard(mp, start, nextf);
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}
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/* break in the sequence, no reassembly */
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start = NULL;
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}
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if (!start)
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break;
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}
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frag = nextf;
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} /* while -- main loop */
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if (mp->frags == NULL)
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mp->frags = frag;
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check_overflow:
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/* rather straighforward way to deal with (not very) possible
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* queue overflow */
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* queue overflow
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*/
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if (mp->frames > MP_MAX_QUEUE_LEN) {
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stats->overflows++;
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while (mp->frames > MP_MAX_QUEUE_LEN) {
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frag = mp->frags->next;
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isdn_ppp_mp_free_skb(mp, mp->frags);
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mp->frags = frag;
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skb_queue_walk_safe(&mp->frags, frag, nextf) {
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if (mp->frames <= MP_MAX_QUEUE_LEN)
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break;
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__skb_unlink(frag, &mp->frags);
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isdn_ppp_mp_free_skb(mp, frag);
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}
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}
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spin_unlock_irqrestore(&mp->lock, flags);
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}
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static void isdn_ppp_mp_cleanup( isdn_net_local * lp )
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static void isdn_ppp_mp_cleanup(isdn_net_local *lp)
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{
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struct sk_buff * frag = lp->netdev->pb->frags;
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struct sk_buff * nextfrag;
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while( frag ) {
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nextfrag = frag->next;
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isdn_ppp_mp_free_skb(lp->netdev->pb, frag);
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frag = nextfrag;
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struct sk_buff *skb, *tmp;
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skb_queue_walk_safe(&lp->netdev->pb->frags, skb, tmp) {
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__skb_unlink(skb, &lp->netdev->pb->frags);
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isdn_ppp_mp_free_skb(lp->netdev->pb, skb);
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}
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lp->netdev->pb->frags = NULL;
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}
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static u32 isdn_ppp_mp_get_seq( int short_seq,
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@ -1853,72 +1836,115 @@ static u32 isdn_ppp_mp_get_seq( int short_seq,
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return seq;
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}
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struct sk_buff * isdn_ppp_mp_discard( ippp_bundle * mp,
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struct sk_buff * from, struct sk_buff * to )
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static void isdn_ppp_mp_discard(ippp_bundle *mp, struct sk_buff *from,
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struct sk_buff *to)
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{
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if( from )
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while (from != to) {
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struct sk_buff * next = from->next;
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isdn_ppp_mp_free_skb(mp, from);
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from = next;
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if (from) {
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struct sk_buff *skb, *tmp;
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int freeing = 0;
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skb_queue_walk_safe(&mp->frags, skb, tmp) {
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if (skb == to)
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break;
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if (skb == from)
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freeing = 1;
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if (!freeing)
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continue;
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__skb_unlink(skb, &mp->frags);
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isdn_ppp_mp_free_skb(mp, skb);
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}
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}
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return from;
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}
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void isdn_ppp_mp_reassembly( isdn_net_dev * net_dev, isdn_net_local * lp,
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struct sk_buff * from, struct sk_buff * to )
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static unsigned int calc_tot_len(struct sk_buff_head *queue,
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struct sk_buff *from, struct sk_buff *to)
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{
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ippp_bundle * mp = net_dev->pb;
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int proto;
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struct sk_buff * skb;
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unsigned int tot_len = 0;
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struct sk_buff *skb;
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int found_start = 0;
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skb_queue_walk(queue, skb) {
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if (skb == from)
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found_start = 1;
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if (!found_start)
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continue;
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tot_len += skb->len - MP_HEADER_LEN;
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if (skb == to)
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break;
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}
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return tot_len;
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}
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/* Reassemble packet using fragments in the reassembly queue from
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* 'from' until 'to', inclusive.
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*/
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static void isdn_ppp_mp_reassembly(isdn_net_dev *net_dev, isdn_net_local *lp,
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struct sk_buff *from, struct sk_buff *to,
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u32 lastseq)
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{
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ippp_bundle *mp = net_dev->pb;
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unsigned int tot_len;
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struct sk_buff *skb;
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int proto;
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if (lp->ppp_slot < 0 || lp->ppp_slot >= ISDN_MAX_CHANNELS) {
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printk(KERN_ERR "%s: lp->ppp_slot(%d) out of range\n",
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__func__, lp->ppp_slot);
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return;
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}
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if( MP_FLAGS(from) == (MP_BEGIN_FRAG | MP_END_FRAG) ) {
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if( ippp_table[lp->ppp_slot]->debug & 0x40 )
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tot_len = calc_tot_len(&mp->frags, from, to);
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if (MP_FLAGS(from) == (MP_BEGIN_FRAG | MP_END_FRAG)) {
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if (ippp_table[lp->ppp_slot]->debug & 0x40)
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printk(KERN_DEBUG "isdn_mppp: reassembly: frame %d, "
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"len %d\n", MP_SEQ(from), from->len );
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"len %d\n", MP_SEQ(from), from->len);
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skb = from;
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skb_pull(skb, MP_HEADER_LEN);
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__skb_unlink(skb, &mp->frags);
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mp->frames--;
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} else {
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struct sk_buff * frag;
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int n;
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struct sk_buff *walk, *tmp;
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int found_start = 0;
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for(tot_len=n=0, frag=from; frag != to; frag=frag->next, n++)
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tot_len += frag->len - MP_HEADER_LEN;
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if( ippp_table[lp->ppp_slot]->debug & 0x40 )
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if (ippp_table[lp->ppp_slot]->debug & 0x40)
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printk(KERN_DEBUG"isdn_mppp: reassembling frames %d "
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"to %d, len %d\n", MP_SEQ(from),
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(MP_SEQ(from)+n-1) & MP_LONGSEQ_MASK, tot_len );
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if( (skb = dev_alloc_skb(tot_len)) == NULL ) {
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"to %d, len %d\n", MP_SEQ(from), lastseq,
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tot_len);
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skb = dev_alloc_skb(tot_len);
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if (!skb)
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printk(KERN_ERR "isdn_mppp: cannot allocate sk buff "
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"of size %d\n", tot_len);
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isdn_ppp_mp_discard(mp, from, to);
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return;
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}
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while( from != to ) {
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unsigned int len = from->len - MP_HEADER_LEN;
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found_start = 0;
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skb_queue_walk_safe(&mp->frags, walk, tmp) {
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if (walk == from)
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found_start = 1;
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if (!found_start)
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continue;
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skb_copy_from_linear_data_offset(from, MP_HEADER_LEN,
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skb_put(skb,len),
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if (skb) {
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unsigned int len = walk->len - MP_HEADER_LEN;
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skb_copy_from_linear_data_offset(walk, MP_HEADER_LEN,
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skb_put(skb, len),
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len);
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frag = from->next;
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isdn_ppp_mp_free_skb(mp, from);
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from = frag;
|
||||
}
|
||||
__skb_unlink(walk, &mp->frags);
|
||||
isdn_ppp_mp_free_skb(mp, walk);
|
||||
|
||||
if (walk == to)
|
||||
break;
|
||||
}
|
||||
}
|
||||
if (!skb)
|
||||
return;
|
||||
|
||||
proto = isdn_ppp_strip_proto(skb);
|
||||
isdn_ppp_push_higher(net_dev, lp, skb, proto);
|
||||
}
|
||||
|
||||
static void isdn_ppp_mp_free_skb(ippp_bundle * mp, struct sk_buff * skb)
|
||||
static void isdn_ppp_mp_free_skb(ippp_bundle *mp, struct sk_buff *skb)
|
||||
{
|
||||
dev_kfree_skb(skb);
|
||||
mp->frames--;
|
||||
|
||||
@ -157,7 +157,7 @@ typedef struct {
|
||||
|
||||
typedef struct {
|
||||
int mp_mrru; /* unused */
|
||||
struct sk_buff * frags; /* fragments sl list -- use skb->next */
|
||||
struct sk_buff_head frags; /* fragments sl list */
|
||||
long frames; /* number of frames in the frame list */
|
||||
unsigned int seq; /* last processed packet seq #: any packets
|
||||
* with smaller seq # will be dropped
|
||||
|
||||
Loading…
Reference in New Issue
Block a user