summaryrefslogtreecommitdiffstats
path: root/drivers/isdn/mISDN/hwchannel.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/isdn/mISDN/hwchannel.c')
-rw-r--r--drivers/isdn/mISDN/hwchannel.c162
1 files changed, 144 insertions, 18 deletions
diff --git a/drivers/isdn/mISDN/hwchannel.c b/drivers/isdn/mISDN/hwchannel.c
index c74c363554c..ef34fd40867 100644
--- a/drivers/isdn/mISDN/hwchannel.c
+++ b/drivers/isdn/mISDN/hwchannel.c
@@ -81,10 +81,16 @@ mISDN_initdchannel(struct dchannel *ch, int maxlen, void *phf)
EXPORT_SYMBOL(mISDN_initdchannel);
int
-mISDN_initbchannel(struct bchannel *ch, int maxlen)
+mISDN_initbchannel(struct bchannel *ch, unsigned short maxlen,
+ unsigned short minlen)
{
ch->Flags = 0;
+ ch->minlen = minlen;
+ ch->next_minlen = minlen;
+ ch->init_minlen = minlen;
ch->maxlen = maxlen;
+ ch->next_maxlen = maxlen;
+ ch->init_maxlen = maxlen;
ch->hw = NULL;
ch->rx_skb = NULL;
ch->tx_skb = NULL;
@@ -134,6 +140,14 @@ mISDN_clear_bchannel(struct bchannel *ch)
test_and_clear_bit(FLG_TX_BUSY, &ch->Flags);
test_and_clear_bit(FLG_TX_NEXT, &ch->Flags);
test_and_clear_bit(FLG_ACTIVE, &ch->Flags);
+ test_and_clear_bit(FLG_FILLEMPTY, &ch->Flags);
+ test_and_clear_bit(FLG_TX_EMPTY, &ch->Flags);
+ test_and_clear_bit(FLG_RX_OFF, &ch->Flags);
+ ch->dropcnt = 0;
+ ch->minlen = ch->init_minlen;
+ ch->next_minlen = ch->init_minlen;
+ ch->maxlen = ch->init_maxlen;
+ ch->next_maxlen = ch->init_maxlen;
}
EXPORT_SYMBOL(mISDN_clear_bchannel);
@@ -148,6 +162,51 @@ mISDN_freebchannel(struct bchannel *ch)
}
EXPORT_SYMBOL(mISDN_freebchannel);
+int
+mISDN_ctrl_bchannel(struct bchannel *bch, struct mISDN_ctrl_req *cq)
+{
+ int ret = 0;
+
+ switch (cq->op) {
+ case MISDN_CTRL_GETOP:
+ cq->op = MISDN_CTRL_RX_BUFFER | MISDN_CTRL_FILL_EMPTY |
+ MISDN_CTRL_RX_OFF;
+ break;
+ case MISDN_CTRL_FILL_EMPTY:
+ if (cq->p1) {
+ memset(bch->fill, cq->p2 & 0xff, MISDN_BCH_FILL_SIZE);
+ test_and_set_bit(FLG_FILLEMPTY, &bch->Flags);
+ } else {
+ test_and_clear_bit(FLG_FILLEMPTY, &bch->Flags);
+ }
+ break;
+ case MISDN_CTRL_RX_OFF:
+ /* read back dropped byte count */
+ cq->p2 = bch->dropcnt;
+ if (cq->p1)
+ test_and_set_bit(FLG_RX_OFF, &bch->Flags);
+ else
+ test_and_clear_bit(FLG_RX_OFF, &bch->Flags);
+ bch->dropcnt = 0;
+ break;
+ case MISDN_CTRL_RX_BUFFER:
+ if (cq->p2 > MISDN_CTRL_RX_SIZE_IGNORE)
+ bch->next_maxlen = cq->p2;
+ if (cq->p1 > MISDN_CTRL_RX_SIZE_IGNORE)
+ bch->next_minlen = cq->p1;
+ /* we return the old values */
+ cq->p1 = bch->minlen;
+ cq->p2 = bch->maxlen;
+ break;
+ default:
+ pr_info("mISDN unhandled control %x operation\n", cq->op);
+ ret = -EINVAL;
+ break;
+ }
+ return ret;
+}
+EXPORT_SYMBOL(mISDN_ctrl_bchannel);
+
static inline u_int
get_sapi_tei(u_char *p)
{
@@ -197,24 +256,37 @@ recv_Echannel(struct dchannel *ech, struct dchannel *dch)
EXPORT_SYMBOL(recv_Echannel);
void
-recv_Bchannel(struct bchannel *bch, unsigned int id)
+recv_Bchannel(struct bchannel *bch, unsigned int id, bool force)
{
struct mISDNhead *hh;
- hh = mISDN_HEAD_P(bch->rx_skb);
- hh->prim = PH_DATA_IND;
- hh->id = id;
- if (bch->rcount >= 64) {
- printk(KERN_WARNING "B-channel %p receive queue overflow, "
- "flushing!\n", bch);
- skb_queue_purge(&bch->rqueue);
- bch->rcount = 0;
+ /* if allocation did fail upper functions still may call us */
+ if (unlikely(!bch->rx_skb))
return;
+ if (unlikely(!bch->rx_skb->len)) {
+ /* we have no data to send - this may happen after recovery
+ * from overflow or too small allocation.
+ * We need to free the buffer here */
+ dev_kfree_skb(bch->rx_skb);
+ bch->rx_skb = NULL;
+ } else {
+ if (test_bit(FLG_TRANSPARENT, &bch->Flags) &&
+ (bch->rx_skb->len < bch->minlen) && !force)
+ return;
+ hh = mISDN_HEAD_P(bch->rx_skb);
+ hh->prim = PH_DATA_IND;
+ hh->id = id;
+ if (bch->rcount >= 64) {
+ printk(KERN_WARNING
+ "B%d receive queue overflow - flushing!\n",
+ bch->nr);
+ skb_queue_purge(&bch->rqueue);
+ }
+ bch->rcount++;
+ skb_queue_tail(&bch->rqueue, bch->rx_skb);
+ bch->rx_skb = NULL;
+ schedule_event(bch, FLG_RECVQUEUE);
}
- bch->rcount++;
- skb_queue_tail(&bch->rqueue, bch->rx_skb);
- bch->rx_skb = NULL;
- schedule_event(bch, FLG_RECVQUEUE);
}
EXPORT_SYMBOL(recv_Bchannel);
@@ -272,7 +344,7 @@ get_next_dframe(struct dchannel *dch)
}
EXPORT_SYMBOL(get_next_dframe);
-void
+static void
confirm_Bsend(struct bchannel *bch)
{
struct sk_buff *skb;
@@ -294,7 +366,6 @@ confirm_Bsend(struct bchannel *bch)
skb_queue_tail(&bch->rqueue, skb);
schedule_event(bch, FLG_RECVQUEUE);
}
-EXPORT_SYMBOL(confirm_Bsend);
int
get_next_bframe(struct bchannel *bch)
@@ -305,8 +376,8 @@ get_next_bframe(struct bchannel *bch)
if (bch->tx_skb) {
bch->next_skb = NULL;
test_and_clear_bit(FLG_TX_NEXT, &bch->Flags);
- if (!test_bit(FLG_TRANSPARENT, &bch->Flags))
- confirm_Bsend(bch); /* not for transparent */
+ /* confirm imediately to allow next data */
+ confirm_Bsend(bch);
return 1;
} else {
test_and_clear_bit(FLG_TX_NEXT, &bch->Flags);
@@ -395,7 +466,62 @@ bchannel_senddata(struct bchannel *ch, struct sk_buff *skb)
/* write to fifo */
ch->tx_skb = skb;
ch->tx_idx = 0;
+ confirm_Bsend(ch);
return 1;
}
}
EXPORT_SYMBOL(bchannel_senddata);
+
+/* The function allocates a new receive skb on demand with a size for the
+ * requirements of the current protocol. It returns the tailroom of the
+ * receive skb or an error.
+ */
+int
+bchannel_get_rxbuf(struct bchannel *bch, int reqlen)
+{
+ int len;
+
+ if (bch->rx_skb) {
+ len = skb_tailroom(bch->rx_skb);
+ if (len < reqlen) {
+ pr_warning("B%d no space for %d (only %d) bytes\n",
+ bch->nr, reqlen, len);
+ if (test_bit(FLG_TRANSPARENT, &bch->Flags)) {
+ /* send what we have now and try a new buffer */
+ recv_Bchannel(bch, 0, true);
+ } else {
+ /* on HDLC we have to drop too big frames */
+ return -EMSGSIZE;
+ }
+ } else {
+ return len;
+ }
+ }
+ /* update current min/max length first */
+ if (unlikely(bch->maxlen != bch->next_maxlen))
+ bch->maxlen = bch->next_maxlen;
+ if (unlikely(bch->minlen != bch->next_minlen))
+ bch->minlen = bch->next_minlen;
+ if (unlikely(reqlen > bch->maxlen))
+ return -EMSGSIZE;
+ if (test_bit(FLG_TRANSPARENT, &bch->Flags)) {
+ if (reqlen >= bch->minlen) {
+ len = reqlen;
+ } else {
+ len = 2 * bch->minlen;
+ if (len > bch->maxlen)
+ len = bch->maxlen;
+ }
+ } else {
+ /* with HDLC we do not know the length yet */
+ len = bch->maxlen;
+ }
+ bch->rx_skb = mI_alloc_skb(len, GFP_ATOMIC);
+ if (!bch->rx_skb) {
+ pr_warning("B%d receive no memory for %d bytes\n",
+ bch->nr, len);
+ len = -ENOMEM;
+ }
+ return len;
+}
+EXPORT_SYMBOL(bchannel_get_rxbuf);