/**
@brief copy UDL data in an skb to a circular TXQ
Enqueues a frame in @b @@skb to the @b @@dev TXQ if there is enough space in the
TXQ, then releases @b @@skb.
@param mld the pointer to a mem_link_device instance
@param dev the pointer to a mem_ipc_device instance
@param skb the pointer to an sk_buff instance
@retval "> 0" the size of the frame written in the TXQ
@retval "< 0" an error code (-EBUSY, -ENOSPC, or -EIO)
*/
static inline int udl_write(struct mem_link_device *mld,
struct mem_ipc_device *dev, struct sk_buff *skb)
{
unsigned int count = skb->len;
char *src = skb->data;
char *dst = get_txq_buff(dev);
unsigned int qsize = get_txq_buff_size(dev);
unsigned int in = get_txq_head(dev);
unsigned int out = get_txq_tail(dev);
int space;
space = check_udl_space(mld, dev, qsize, in, out, count);
if (unlikely(space < 0))
return space;
barrier();
circ_write(dst, src, qsize, in, count);
barrier();
set_txq_head(dev, circ_new_ptr(qsize, in, count));
/* Commit the item before incrementing the head */
smp_mb();
return count;
}
/**
@brief copy data in an skb to a circular TXQ
Enqueues a frame in @b @@skb to the @b @@dev TXQ if there is enough space in the
TXQ, then releases @b @@skb.
@param mld the pointer to a mem_link_device instance
@param dev the pointer to a mem_ipc_device instance
@param skb the pointer to an sk_buff instance
@retval "> 0" the size of the frame written in the TXQ
@retval "< 0" an error code (-EBUSY, -ENOSPC, or -EIO)
*/
static int txq_write(struct mem_link_device *mld, struct mem_ipc_device *dev,
struct sk_buff *skb)
{
char *src = skb->data;
unsigned int count = skb->len;
char *dst = get_txq_buff(dev);
unsigned int qsize = get_txq_buff_size(dev);
unsigned int in = get_txq_head(dev);
unsigned int out = get_txq_tail(dev);
int space;
space = check_txq_space(mld, dev, qsize, in, out, count);
if (unlikely(space < 0))
return space;
#ifdef DEBUG_MODEM_IF_LINK_TX
/* Record the time-stamp */
getnstimeofday(&skbpriv(skb)->ts);
#endif
circ_write(dst, src, qsize, in, count);
set_txq_head(dev, circ_new_ptr(qsize, in, count));
/* Commit the item before incrementing the head */
smp_mb();
#ifdef DEBUG_MODEM_IF_LINK_TX
if (likely(src))
log_ipc_pkt(sipc5_get_ch_id(src), LINK, TX, skb, true, true);
#endif
dev_kfree_skb_any(skb);
return count;
}