diff options
Diffstat (limited to 'drivers/isdn/i4l/isdn_ppp.c')
| -rw-r--r-- | drivers/isdn/i4l/isdn_ppp.c | 352 |
1 files changed, 189 insertions, 163 deletions
diff --git a/drivers/isdn/i4l/isdn_ppp.c b/drivers/isdn/i4l/isdn_ppp.c index 127cfdad68e..77c280ef2eb 100644 --- a/drivers/isdn/i4l/isdn_ppp.c +++ b/drivers/isdn/i4l/isdn_ppp.c @@ -1533,8 +1533,10 @@ static int isdn_ppp_mp_bundle_array_init(void) int sz = ISDN_MAX_CHANNELS*sizeof(ippp_bundle); if( (isdn_ppp_bundle_arr = kzalloc(sz, GFP_KERNEL)) == NULL ) return -ENOMEM; - for( i = 0; i < ISDN_MAX_CHANNELS; i++ ) + for (i = 0; i < ISDN_MAX_CHANNELS; i++) { spin_lock_init(&isdn_ppp_bundle_arr[i].lock); + skb_queue_head_init(&isdn_ppp_bundle_arr[i].frags); + } return 0; } @@ -1567,7 +1569,7 @@ static int isdn_ppp_mp_init( isdn_net_local * lp, ippp_bundle * add_to ) if ((lp->netdev->pb = isdn_ppp_mp_bundle_alloc()) == NULL) return -ENOMEM; lp->next = lp->last = lp; /* nobody else in a queue */ - lp->netdev->pb->frags = NULL; + skb_queue_head_init(&lp->netdev->pb->frags); lp->netdev->pb->frames = 0; lp->netdev->pb->seq = UINT_MAX; } @@ -1579,28 +1581,29 @@ static int isdn_ppp_mp_init( isdn_net_local * lp, ippp_bundle * add_to ) static u32 isdn_ppp_mp_get_seq( int short_seq, struct sk_buff * skb, u32 last_seq ); -static struct sk_buff * isdn_ppp_mp_discard( ippp_bundle * mp, - struct sk_buff * from, struct sk_buff * to ); -static void isdn_ppp_mp_reassembly( isdn_net_dev * net_dev, isdn_net_local * lp, - struct sk_buff * from, struct sk_buff * to ); -static void isdn_ppp_mp_free_skb( ippp_bundle * mp, struct sk_buff * skb ); +static void isdn_ppp_mp_discard(ippp_bundle *mp, struct sk_buff *from, + struct sk_buff *to); +static void isdn_ppp_mp_reassembly(isdn_net_dev *net_dev, isdn_net_local *lp, + struct sk_buff *from, struct sk_buff *to, + u32 lastseq); +static void isdn_ppp_mp_free_skb(ippp_bundle *mp, struct sk_buff *skb); static void isdn_ppp_mp_print_recv_pkt( int slot, struct sk_buff * skb ); static void isdn_ppp_mp_receive(isdn_net_dev * net_dev, isdn_net_local * lp, - struct sk_buff *skb) + struct sk_buff *skb) { - struct ippp_struct *is; - isdn_net_local * lpq; - ippp_bundle * mp; - isdn_mppp_stats * stats; - struct sk_buff * newfrag, * frag, * start, *nextf; + struct sk_buff *newfrag, *frag, *start, *nextf; u32 newseq, minseq, thisseq; + isdn_mppp_stats *stats; + struct ippp_struct *is; unsigned long flags; + isdn_net_local *lpq; + ippp_bundle *mp; int slot; spin_lock_irqsave(&net_dev->pb->lock, flags); - mp = net_dev->pb; - stats = &mp->stats; + mp = net_dev->pb; + stats = &mp->stats; slot = lp->ppp_slot; if (slot < 0 || slot >= ISDN_MAX_CHANNELS) { printk(KERN_ERR "%s: lp->ppp_slot(%d)\n", @@ -1611,20 +1614,19 @@ static void isdn_ppp_mp_receive(isdn_net_dev * net_dev, isdn_net_local * lp, return; } is = ippp_table[slot]; - if( ++mp->frames > stats->max_queue_len ) + if (++mp->frames > stats->max_queue_len) stats->max_queue_len = mp->frames; - + if (is->debug & 0x8) isdn_ppp_mp_print_recv_pkt(lp->ppp_slot, skb); - newseq = isdn_ppp_mp_get_seq(is->mpppcfg & SC_IN_SHORT_SEQ, - skb, is->last_link_seqno); - + newseq = isdn_ppp_mp_get_seq(is->mpppcfg & SC_IN_SHORT_SEQ, + skb, is->last_link_seqno); /* if this packet seq # is less than last already processed one, * toss it right away, but check for sequence start case first */ - if( mp->seq > MP_LONGSEQ_MAX && (newseq & MP_LONGSEQ_MAXBIT) ) { + if (mp->seq > MP_LONGSEQ_MAX && (newseq & MP_LONGSEQ_MAXBIT)) { mp->seq = newseq; /* the first packet: required for * rfc1990 non-compliant clients -- * prevents constant packet toss */ @@ -1634,7 +1636,7 @@ static void isdn_ppp_mp_receive(isdn_net_dev * net_dev, isdn_net_local * lp, spin_unlock_irqrestore(&mp->lock, flags); return; } - + /* find the minimum received sequence number over all links */ is->last_link_seqno = minseq = newseq; for (lpq = net_dev->queue;;) { @@ -1655,22 +1657,31 @@ static void isdn_ppp_mp_receive(isdn_net_dev * net_dev, isdn_net_local * lp, * packets */ newfrag = skb; - /* if this new fragment is before the first one, then enqueue it now. */ - if ((frag = mp->frags) == NULL || MP_LT(newseq, MP_SEQ(frag))) { - newfrag->next = frag; - mp->frags = frag = newfrag; - newfrag = NULL; - } + /* Insert new fragment into the proper sequence slot. */ + skb_queue_walk(&mp->frags, frag) { + if (MP_SEQ(frag) == newseq) { + isdn_ppp_mp_free_skb(mp, newfrag); + newfrag = NULL; + break; + } + if (MP_LT(newseq, MP_SEQ(frag))) { + __skb_queue_before(&mp->frags, frag, newfrag); + newfrag = NULL; + break; + } + } + if (newfrag) + __skb_queue_tail(&mp->frags, newfrag); - start = MP_FLAGS(frag) & MP_BEGIN_FRAG && - MP_SEQ(frag) == mp->seq ? frag : NULL; + frag = skb_peek(&mp->frags); + start = ((MP_FLAGS(frag) & MP_BEGIN_FRAG) && + (MP_SEQ(frag) == mp->seq)) ? frag : NULL; + if (!start) + goto check_overflow; - /* - * main fragment traversing loop + /* main fragment traversing loop * * try to accomplish several tasks: - * - insert new fragment into the proper sequence slot (once that's done - * newfrag will be set to NULL) * - reassemble any complete fragment sequence (non-null 'start' * indicates there is a continguous sequence present) * - discard any incomplete sequences that are below minseq -- due @@ -1679,71 +1690,46 @@ static void isdn_ppp_mp_receive(isdn_net_dev * net_dev, isdn_net_local * lp, * come to complete such sequence and it should be discarded * * loop completes when we accomplished the following tasks: - * - new fragment is inserted in the proper sequence ('newfrag' is - * set to NULL) * - we hit a gap in the sequence, so no reassembly/processing is * possible ('start' would be set to NULL) * * algorithm for this code is derived from code in the book * 'PPP Design And Debugging' by James Carlson (Addison-Wesley) */ - while (start != NULL || newfrag != NULL) { - - thisseq = MP_SEQ(frag); - nextf = frag->next; - - /* drop any duplicate fragments */ - if (newfrag != NULL && thisseq == newseq) { - isdn_ppp_mp_free_skb(mp, newfrag); - newfrag = NULL; - } - - /* insert new fragment before next element if possible. */ - if (newfrag != NULL && (nextf == NULL || - MP_LT(newseq, MP_SEQ(nextf)))) { - newfrag->next = nextf; - frag->next = nextf = newfrag; - newfrag = NULL; - } - - if (start != NULL) { - /* check for misplaced start */ - if (start != frag && (MP_FLAGS(frag) & MP_BEGIN_FRAG)) { - printk(KERN_WARNING"isdn_mppp(seq %d): new " - "BEGIN flag with no prior END", thisseq); - stats->seqerrs++; - stats->frame_drops++; - start = isdn_ppp_mp_discard(mp, start,frag); - nextf = frag->next; - } - } else if (MP_LE(thisseq, minseq)) { - if (MP_FLAGS(frag) & MP_BEGIN_FRAG) + skb_queue_walk_safe(&mp->frags, frag, nextf) { + thisseq = MP_SEQ(frag); + + /* check for misplaced start */ + if (start != frag && (MP_FLAGS(frag) & MP_BEGIN_FRAG)) { + printk(KERN_WARNING"isdn_mppp(seq %d): new " + "BEGIN flag with no prior END", thisseq); + stats->seqerrs++; + stats->frame_drops++; + isdn_ppp_mp_discard(mp, start, frag); + start = frag; + } else if (MP_LE(thisseq, minseq)) { + if (MP_FLAGS(frag) & MP_BEGIN_FRAG) start = frag; - else { + else { if (MP_FLAGS(frag) & MP_END_FRAG) - stats->frame_drops++; - if( mp->frags == frag ) - mp->frags = nextf; + stats->frame_drops++; + __skb_unlink(skb, &mp->frags); isdn_ppp_mp_free_skb(mp, frag); - frag = nextf; continue; - } + } } - - /* if start is non-null and we have end fragment, then - * we have full reassembly sequence -- reassemble - * and process packet now + + /* if we have end fragment, then we have full reassembly + * sequence -- reassemble and process packet now */ - if (start != NULL && (MP_FLAGS(frag) & MP_END_FRAG)) { - minseq = mp->seq = (thisseq+1) & MP_LONGSEQ_MASK; - /* Reassemble the packet then dispatch it */ - isdn_ppp_mp_reassembly(net_dev, lp, start, nextf); - - start = NULL; - frag = NULL; + if (MP_FLAGS(frag) & MP_END_FRAG) { + minseq = mp->seq = (thisseq+1) & MP_LONGSEQ_MASK; + /* Reassemble the packet then dispatch it */ + isdn_ppp_mp_reassembly(net_dev, lp, start, frag, thisseq); - mp->frags = nextf; - } + start = NULL; + frag = NULL; + } /* check if need to update start pointer: if we just * reassembled the packet and sequence is contiguous @@ -1754,26 +1740,25 @@ static void isdn_ppp_mp_receive(isdn_net_dev * net_dev, isdn_net_local * lp, * below low watermark and set start to the next frag or * clear start ptr. */ - if (nextf != NULL && + if (nextf != (struct sk_buff *)&mp->frags && ((thisseq+1) & MP_LONGSEQ_MASK) == MP_SEQ(nextf)) { - /* if we just reassembled and the next one is here, - * then start another reassembly. */ - - if (frag == NULL) { + /* if we just reassembled and the next one is here, + * then start another reassembly. + */ + if (frag == NULL) { if (MP_FLAGS(nextf) & MP_BEGIN_FRAG) - start = nextf; - else - { - printk(KERN_WARNING"isdn_mppp(seq %d):" - " END flag with no following " - "BEGIN", thisseq); + start = nextf; + else { + printk(KERN_WARNING"isdn_mppp(seq %d):" + " END flag with no following " + "BEGIN", thisseq); stats->seqerrs++; } } - - } else { - if ( nextf != NULL && frag != NULL && - MP_LT(thisseq, minseq)) { + } else { + if (nextf != (struct sk_buff *)&mp->frags && + frag != NULL && + MP_LT(thisseq, minseq)) { /* we've got a break in the sequence * and we not at the end yet * and we did not just reassembled @@ -1782,41 +1767,39 @@ static void isdn_ppp_mp_receive(isdn_net_dev * net_dev, isdn_net_local * lp, * discard all the frames below low watermark * and start over */ stats->frame_drops++; - mp->frags = isdn_ppp_mp_discard(mp,start,nextf); + isdn_ppp_mp_discard(mp, start, nextf); } /* break in the sequence, no reassembly */ - start = NULL; - } - - frag = nextf; - } /* while -- main loop */ - - if (mp->frags == NULL) - mp->frags = frag; - + start = NULL; + } + if (!start) + break; + } + +check_overflow: /* rather straighforward way to deal with (not very) possible - * queue overflow */ + * queue overflow + */ if (mp->frames > MP_MAX_QUEUE_LEN) { stats->overflows++; - while (mp->frames > MP_MAX_QUEUE_LEN) { - frag = mp->frags->next; - isdn_ppp_mp_free_skb(mp, mp->frags); - mp->frags = frag; + skb_queue_walk_safe(&mp->frags, frag, nextf) { + if (mp->frames <= MP_MAX_QUEUE_LEN) + break; + __skb_unlink(frag, &mp->frags); + isdn_ppp_mp_free_skb(mp, frag); } } spin_unlock_irqrestore(&mp->lock, flags); } -static void isdn_ppp_mp_cleanup( isdn_net_local * lp ) +static void isdn_ppp_mp_cleanup(isdn_net_local *lp) { - struct sk_buff * frag = lp->netdev->pb->frags; - struct sk_buff * nextfrag; - while( frag ) { - nextfrag = frag->next; - isdn_ppp_mp_free_skb(lp->netdev->pb, frag); - frag = nextfrag; - } - lp->netdev->pb->frags = NULL; + struct sk_buff *skb, *tmp; + + skb_queue_walk_safe(&lp->netdev->pb->frags, skb, tmp) { + __skb_unlink(skb, &lp->netdev->pb->frags); + isdn_ppp_mp_free_skb(lp->netdev->pb, skb); + } } static u32 isdn_ppp_mp_get_seq( int short_seq, @@ -1853,72 +1836,115 @@ static u32 isdn_ppp_mp_get_seq( int short_seq, return seq; } -struct sk_buff * isdn_ppp_mp_discard( ippp_bundle * mp, - struct sk_buff * from, struct sk_buff * to ) +static void isdn_ppp_mp_discard(ippp_bundle *mp, struct sk_buff *from, + struct sk_buff *to) { - if( from ) - while (from != to) { - struct sk_buff * next = from->next; - isdn_ppp_mp_free_skb(mp, from); - from = next; + if (from) { + struct sk_buff *skb, *tmp; + int freeing = 0; + + skb_queue_walk_safe(&mp->frags, skb, tmp) { + if (skb == to) + break; + if (skb == from) + freeing = 1; + if (!freeing) + continue; + __skb_unlink(skb, &mp->frags); + isdn_ppp_mp_free_skb(mp, skb); } - return from; + } } -void isdn_ppp_mp_reassembly( isdn_net_dev * net_dev, isdn_net_local * lp, - struct sk_buff * from, struct sk_buff * to ) +static unsigned int calc_tot_len(struct sk_buff_head *queue, + struct sk_buff *from, struct sk_buff *to) { - ippp_bundle * mp = net_dev->pb; - int proto; - struct sk_buff * skb; + unsigned int tot_len = 0; + struct sk_buff *skb; + int found_start = 0; + + skb_queue_walk(queue, skb) { + if (skb == from) + found_start = 1; + if (!found_start) + continue; + tot_len += skb->len - MP_HEADER_LEN; + if (skb == to) + break; + } + return tot_len; +} + +/* Reassemble packet using fragments in the reassembly queue from + * 'from' until 'to', inclusive. + */ +static void isdn_ppp_mp_reassembly(isdn_net_dev *net_dev, isdn_net_local *lp, + struct sk_buff *from, struct sk_buff *to, + u32 lastseq) +{ + ippp_bundle *mp = net_dev->pb; unsigned int tot_len; + struct sk_buff *skb; + int proto; if (lp->ppp_slot < 0 || lp->ppp_slot >= ISDN_MAX_CHANNELS) { printk(KERN_ERR "%s: lp->ppp_slot(%d) out of range\n", __func__, lp->ppp_slot); return; } - if( MP_FLAGS(from) == (MP_BEGIN_FRAG | MP_END_FRAG) ) { - if( ippp_table[lp->ppp_slot]->debug & 0x40 ) + + tot_len = calc_tot_len(&mp->frags, from, to); + + if (MP_FLAGS(from) == (MP_BEGIN_FRAG | MP_END_FRAG)) { + if (ippp_table[lp->ppp_slot]->debug & 0x40) printk(KERN_DEBUG "isdn_mppp: reassembly: frame %d, " - "len %d\n", MP_SEQ(from), from->len ); + "len %d\n", MP_SEQ(from), from->len); skb = from; skb_pull(skb, MP_HEADER_LEN); + __skb_unlink(skb, &mp->frags); mp->frames--; } else { - struct sk_buff * frag; - int n; + struct sk_buff *walk, *tmp; + int found_start = 0; - for(tot_len=n=0, frag=from; frag != to; frag=frag->next, n++) - tot_len += frag->len - MP_HEADER_LEN; - - if( ippp_table[lp->ppp_slot]->debug & 0x40 ) + if (ippp_table[lp->ppp_slot]->debug & 0x40) printk(KERN_DEBUG"isdn_mppp: reassembling frames %d " - "to %d, len %d\n", MP_SEQ(from), - (MP_SEQ(from)+n-1) & MP_LONGSEQ_MASK, tot_len ); - if( (skb = dev_alloc_skb(tot_len)) == NULL ) { + "to %d, len %d\n", MP_SEQ(from), lastseq, + tot_len); + + skb = dev_alloc_skb(tot_len); + if (!skb) printk(KERN_ERR "isdn_mppp: cannot allocate sk buff " - "of size %d\n", tot_len); - isdn_ppp_mp_discard(mp, from, to); - return; - } + "of size %d\n", tot_len); + + found_start = 0; + skb_queue_walk_safe(&mp->frags, walk, tmp) { + if (walk == from) + found_start = 1; + if (!found_start) + continue; - while( from != to ) { - unsigned int len = from->len - MP_HEADER_LEN; + if (skb) { + unsigned int len = walk->len - MP_HEADER_LEN; + skb_copy_from_linear_data_offset(walk, MP_HEADER_LEN, + skb_put(skb, len), + len); + } + __skb_unlink(walk, &mp->frags); + isdn_ppp_mp_free_skb(mp, walk); - skb_copy_from_linear_data_offset(from, MP_HEADER_LEN, - skb_put(skb,len), - len); - frag = from->next; - isdn_ppp_mp_free_skb(mp, from); - from = frag; + 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--; |