diff options
Diffstat (limited to 'drivers/isdn/mISDN/hwchannel.c')
-rw-r--r-- | drivers/isdn/mISDN/hwchannel.c | 162 |
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); |