Skip to content

Commit

Permalink
---
Browse files Browse the repository at this point in the history
yaml
---
r: 135185
b: refs/heads/master
c: 9c70526
h: refs/heads/master
i:
  135183: 9556e8e
v: v3
  • Loading branch information
Gabriele Paoloni authored and David S. Miller committed Mar 13, 2009
1 parent 01e333d commit cb8cbab
Show file tree
Hide file tree
Showing 5 changed files with 128 additions and 93 deletions.
2 changes: 1 addition & 1 deletion [refs]
Original file line number Diff line number Diff line change
@@ -1,2 +1,2 @@
---
refs/heads/master: a2025b8b1039e5abaa38319b2eaab3b17867479a
refs/heads/master: 9c705260feea6ae329bc6b6d5f6d2ef0227eda0a
3 changes: 3 additions & 0 deletions trunk/drivers/net/ppp_async.c
Original file line number Diff line number Diff line change
Expand Up @@ -157,6 +157,7 @@ ppp_asynctty_open(struct tty_struct *tty)
{
struct asyncppp *ap;
int err;
int speed;

if (tty->ops->write == NULL)
return -EOPNOTSUPP;
Expand Down Expand Up @@ -187,6 +188,8 @@ ppp_asynctty_open(struct tty_struct *tty)
ap->chan.private = ap;
ap->chan.ops = &async_ops;
ap->chan.mtu = PPP_MRU;
speed = tty_get_baud_rate(tty);
ap->chan.speed = speed;
err = ppp_register_channel(&ap->chan);
if (err)
goto out_free;
Expand Down
211 changes: 120 additions & 91 deletions trunk/drivers/net/ppp_generic.c
Original file line number Diff line number Diff line change
Expand Up @@ -167,6 +167,7 @@ struct channel {
u8 avail; /* flag used in multilink stuff */
u8 had_frag; /* >= 1 fragments have been sent */
u32 lastseq; /* MP: last sequence # received */
int speed; /* speed of the corresponding ppp channel*/
#endif /* CONFIG_PPP_MULTILINK */
};

Expand Down Expand Up @@ -1307,138 +1308,181 @@ ppp_push(struct ppp *ppp)
*/
static int ppp_mp_explode(struct ppp *ppp, struct sk_buff *skb)
{
int len, fragsize;
int i, bits, hdrlen, mtu;
int flen;
int navail, nfree;
int nbigger;
int len, totlen;
int i, bits, hdrlen, mtu;
int flen;
int navail, nfree, nzero;
int nbigger;
int totspeed;
int totfree;
unsigned char *p, *q;
struct list_head *list;
struct channel *pch;
struct sk_buff *frag;
struct ppp_channel *chan;

nfree = 0; /* # channels which have no packet already queued */
totspeed = 0; /*total bitrate of the bundle*/
nfree = 0; /* # channels which have no packet already queued */
navail = 0; /* total # of usable channels (not deregistered) */
nzero = 0; /* number of channels with zero speed associated*/
totfree = 0; /*total # of channels available and
*having no queued packets before
*starting the fragmentation*/

hdrlen = (ppp->flags & SC_MP_XSHORTSEQ)? MPHDRLEN_SSN: MPHDRLEN;
i = 0;
list_for_each_entry(pch, &ppp->channels, clist) {
i = 0;
list_for_each_entry(pch, &ppp->channels, clist) {
navail += pch->avail = (pch->chan != NULL);
if (pch->avail) {
pch->speed = pch->chan->speed;
if (pch->avail) {
if (skb_queue_empty(&pch->file.xq) ||
!pch->had_frag) {
pch->avail = 2;
++nfree;
}
if (!pch->had_frag && i < ppp->nxchan)
ppp->nxchan = i;
!pch->had_frag) {
if (pch->speed == 0)
nzero++;
else
totspeed += pch->speed;

pch->avail = 2;
++nfree;
++totfree;
}
if (!pch->had_frag && i < ppp->nxchan)
ppp->nxchan = i;
}
++i;
}

/*
* Don't start sending this packet unless at least half of
* the channels are free. This gives much better TCP
* performance if we have a lot of channels.
* Don't start sending this packet unless at least half of
* the channels are free. This gives much better TCP
* performance if we have a lot of channels.
*/
if (nfree == 0 || nfree < navail / 2)
return 0; /* can't take now, leave it in xmit_pending */
if (nfree == 0 || nfree < navail / 2)
return 0; /* can't take now, leave it in xmit_pending */

/* Do protocol field compression (XXX this should be optional) */
p = skb->data;
len = skb->len;
p = skb->data;
len = skb->len;
if (*p == 0) {
++p;
--len;
}

/*
* Decide on fragment size.
* We create a fragment for each free channel regardless of
* how small they are (i.e. even 0 length) in order to minimize
* the time that it will take to detect when a channel drops
* a fragment.
*/
fragsize = len;
if (nfree > 1)
fragsize = DIV_ROUND_UP(fragsize, nfree);
/* nbigger channels get fragsize bytes, the rest get fragsize-1,
except if nbigger==0, then they all get fragsize. */
nbigger = len % nfree;

/* skip to the channel after the one we last used
and start at that one */
totlen = len;
nbigger = len % nfree;

/* skip to the channel after the one we last used
and start at that one */
list = &ppp->channels;
for (i = 0; i < ppp->nxchan; ++i) {
for (i = 0; i < ppp->nxchan; ++i) {
list = list->next;
if (list == &ppp->channels) {
i = 0;
if (list == &ppp->channels) {
i = 0;
break;
}
}

/* create a fragment for each channel */
/* create a fragment for each channel */
bits = B;
while (nfree > 0 || len > 0) {
while (nfree > 0 && len > 0) {
list = list->next;
if (list == &ppp->channels) {
i = 0;
if (list == &ppp->channels) {
i = 0;
continue;
}
pch = list_entry(list, struct channel, clist);
pch = list_entry(list, struct channel, clist);
++i;
if (!pch->avail)
continue;

/*
* Skip this channel if it has a fragment pending already and
* we haven't given a fragment to all of the free channels.
* Skip this channel if it has a fragment pending already and
* we haven't given a fragment to all of the free channels.
*/
if (pch->avail == 1) {
if (nfree > 0)
if (nfree > 0)
continue;
} else {
--nfree;
pch->avail = 1;
}

/* check the channel's mtu and whether it is still attached. */
spin_lock_bh(&pch->downl);
if (pch->chan == NULL) {
/* can't use this channel, it's being deregistered */
/* can't use this channel, it's being deregistered */
if (pch->speed == 0)
nzero--;
else
totspeed -= pch->speed;

spin_unlock_bh(&pch->downl);
pch->avail = 0;
if (--navail == 0)
totlen = len;
totfree--;
nfree--;
if (--navail == 0)
break;
continue;
}

/*
* Create a fragment for this channel of
* min(max(mtu+2-hdrlen, 4), fragsize, len) bytes.
* If mtu+2-hdrlen < 4, that is a ridiculously small
* MTU, so we use mtu = 2 + hdrlen.
*if the channel speed is not set divide
*the packet evenly among the free channels;
*otherwise divide it according to the speed
*of the channel we are going to transmit on
*/
if (pch->speed == 0) {
flen = totlen/nfree ;
if (nbigger > 0) {
flen++;
nbigger--;
}
} else {
flen = (((totfree - nzero)*(totlen + hdrlen*totfree)) /
((totspeed*totfree)/pch->speed)) - hdrlen;
if (nbigger > 0) {
flen += ((totfree - nzero)*pch->speed)/totspeed;
nbigger -= ((totfree - nzero)*pch->speed)/
totspeed;
}
}
nfree--;

/*
*check if we are on the last channel or
*we exceded the lenght of the data to
*fragment
*/
if ((nfree == 0) || (flen > len))
flen = len;
/*
*it is not worth to tx on slow channels:
*in that case from the resulting flen according to the
*above formula will be equal or less than zero.
*Skip the channel in this case
*/
if (fragsize > len)
fragsize = len;
flen = fragsize;
mtu = pch->chan->mtu + 2 - hdrlen;
if (mtu < 4)
mtu = 4;
if (flen <= 0) {
pch->avail = 2;
spin_unlock_bh(&pch->downl);
continue;
}

mtu = pch->chan->mtu + 2 - hdrlen;
if (mtu < 4)
mtu = 4;
if (flen > mtu)
flen = mtu;
if (flen == len && nfree == 0)
bits |= E;
frag = alloc_skb(flen + hdrlen + (flen == 0), GFP_ATOMIC);
if (flen == len)
bits |= E;
frag = alloc_skb(flen + hdrlen + (flen == 0), GFP_ATOMIC);
if (!frag)
goto noskb;
q = skb_put(frag, flen + hdrlen);
q = skb_put(frag, flen + hdrlen);

/* make the MP header */
/* make the MP header */
q[0] = PPP_MP >> 8;
q[1] = PPP_MP;
if (ppp->flags & SC_MP_XSHORTSEQ) {
q[2] = bits + ((ppp->nxseq >> 8) & 0xf);
q[2] = bits + ((ppp->nxseq >> 8) & 0xf);
q[3] = ppp->nxseq;
} else {
q[2] = bits;
Expand All @@ -1447,43 +1491,28 @@ static int ppp_mp_explode(struct ppp *ppp, struct sk_buff *skb)
q[5] = ppp->nxseq;
}

/*
* Copy the data in.
* Unfortunately there is a bug in older versions of
* the Linux PPP multilink reconstruction code where it
* drops 0-length fragments. Therefore we make sure the
* fragment has at least one byte of data. Any bytes
* we add in this situation will end up as padding on the
* end of the reconstructed packet.
*/
if (flen == 0)
*skb_put(frag, 1) = 0;
else
memcpy(q + hdrlen, p, flen);
memcpy(q + hdrlen, p, flen);

/* try to send it down the channel */
chan = pch->chan;
if (!skb_queue_empty(&pch->file.xq) ||
!chan->ops->start_xmit(chan, frag))
if (!skb_queue_empty(&pch->file.xq) ||
!chan->ops->start_xmit(chan, frag))
skb_queue_tail(&pch->file.xq, frag);
pch->had_frag = 1;
pch->had_frag = 1;
p += flen;
len -= flen;
len -= flen;
++ppp->nxseq;
bits = 0;
spin_unlock_bh(&pch->downl);

if (--nbigger == 0 && fragsize > 0)
--fragsize;
}
ppp->nxchan = i;
ppp->nxchan = i;

return 1;

noskb:
spin_unlock_bh(&pch->downl);
if (ppp->debug & 1)
printk(KERN_ERR "PPP: no memory (fragment)\n");
printk(KERN_ERR "PPP: no memory (fragment)\n");
++ppp->dev->stats.tx_errors;
++ppp->nxseq;
return 1; /* abandon the frame */
Expand Down
3 changes: 3 additions & 0 deletions trunk/drivers/net/ppp_synctty.c
Original file line number Diff line number Diff line change
Expand Up @@ -206,6 +206,7 @@ ppp_sync_open(struct tty_struct *tty)
{
struct syncppp *ap;
int err;
int speed;

if (tty->ops->write == NULL)
return -EOPNOTSUPP;
Expand Down Expand Up @@ -234,6 +235,8 @@ ppp_sync_open(struct tty_struct *tty)
ap->chan.ops = &sync_ops;
ap->chan.mtu = PPP_MRU;
ap->chan.hdrlen = 2; /* for A/C bytes */
speed = tty_get_baud_rate(tty);
ap->chan.speed = speed;
err = ppp_register_channel(&ap->chan);
if (err)
goto out_free;
Expand Down
2 changes: 1 addition & 1 deletion trunk/include/linux/ppp_channel.h
Original file line number Diff line number Diff line change
Expand Up @@ -40,8 +40,8 @@ struct ppp_channel {
int mtu; /* max transmit packet size */
int hdrlen; /* amount of headroom channel needs */
void *ppp; /* opaque to channel */
/* the following are not used at present */
int speed; /* transfer rate (bytes/second) */
/* the following is not used at present */
int latency; /* overhead time in milliseconds */
};

Expand Down

0 comments on commit cb8cbab

Please sign in to comment.