diff options
| -rw-r--r-- | drivers/dahdi/wctc4xxp/base.c | 80 |
1 files changed, 49 insertions, 31 deletions
diff --git a/drivers/dahdi/wctc4xxp/base.c b/drivers/dahdi/wctc4xxp/base.c index 1f250be..03eda38 100644 --- a/drivers/dahdi/wctc4xxp/base.c +++ b/drivers/dahdi/wctc4xxp/base.c @@ -1,7 +1,7 @@ /* * Wildcard TC400B Driver * - * Copyright (C) 2006-2009, Digium, Inc. + * Copyright (C) 2006-2010, Digium, Inc. * * All rights reserved. * @@ -2038,6 +2038,8 @@ wctc4xxp_read(struct file *file, char __user *frame, size_t count, loff_t *ppos) struct tcb *cmd; struct rtp_packet *packet; ssize_t payload_bytes; + ssize_t returned_bytes = 0; + unsigned long flags; BUG_ON(!dtc); BUG_ON(!cpvt); @@ -2050,48 +2052,64 @@ wctc4xxp_read(struct file *file, char __user *frame, size_t count, loff_t *ppos) cmd = get_ready_cmd(dtc); if (!cmd) { - if (file->f_flags & O_NONBLOCK) { + if (file->f_flags & O_NONBLOCK) return -EAGAIN; - } else { - ret = wait_event_interruptible(dtc->ready, + ret = wait_event_interruptible(dtc->ready, dahdi_tc_is_data_waiting(dtc)); - if (-ERESTARTSYS == ret) { - /* Signal interrupted the wait */ - return -EINTR; - } else { - /* List went not empty. */ - cmd = get_ready_cmd(dtc); - } - } + if (-ERESTARTSYS == ret) + return -EINTR; + /* List went not empty. */ + cmd = get_ready_cmd(dtc); } - BUG_ON(!cmd); - packet = cmd->data; + do { + BUG_ON(!cmd); + packet = cmd->data; + + payload_bytes = be16_to_cpu(packet->udphdr.len) - + sizeof(struct rtphdr) - + sizeof(struct udphdr); + + if (count < (payload_bytes + returned_bytes)) { + if (returned_bytes) { + /* If we have already returned at least one + * packets worth of data, we'll add this next + * packet to the head of the receive queue so + * it will be picked up next time. */ + spin_lock_irqsave(&cpvt->lock, flags); + list_add(&cmd->node, &cpvt->rx_queue); + dahdi_tc_set_data_waiting(dtc); + spin_unlock_irqrestore(&cpvt->lock, flags); + return returned_bytes; + } + + if (printk_ratelimit()) { + DTE_PRINTK(ERR, + "Cannot copy %zd bytes into %zd byte user " \ + "buffer.\n", payload_bytes, count); + } + free_cmd(cmd); + return -EFBIG; + } - payload_bytes = be16_to_cpu(packet->udphdr.len) - - sizeof(struct rtphdr) - sizeof(struct udphdr); + atomic_inc(&cpvt->stats.packets_received); - if (count < payload_bytes) { - if (printk_ratelimit()) { - DTE_PRINTK(ERR, - "Cannot copy %zd bytes into %zd byte user " \ - "buffer.\n", payload_bytes, count); + ret = copy_to_user(&frame[returned_bytes], + &packet->payload[0], payload_bytes); + if (unlikely(ret)) { + DTE_PRINTK(ERR, "Failed to copy data in %s\n", + __func__); + free_cmd(cmd); + return -EFAULT; } - free_cmd(cmd); - return -EFBIG; - } - atomic_inc(&cpvt->stats.packets_received); + returned_bytes += payload_bytes; - if (unlikely(copy_to_user(frame, &packet->payload[0], payload_bytes))) { - DTE_PRINTK(ERR, "Failed to copy data in %s\n", __func__); free_cmd(cmd); - return -EFAULT; - } - free_cmd(cmd); + } while ((cmd = get_ready_cmd(dtc))); - return payload_bytes; + return returned_bytes; } /* Called with a frame in the srcfmt to be transcoded into the dstfmt. */ |