Commit 238a0f7c authored by Brett Creeley's avatar Brett Creeley Committed by David S. Miller
Browse files

ionic: Cleanups in the Tx hotpath code 



Buffer DMA mapping happens in ionic_tx_map_skb() and this function is
called from ionic_tx() and ionic_tx_tso(). If ionic_tx_map_skb()
succeeds, but a failure is encountered later in ionic_tx() or
ionic_tx_tso() we aren't unmapping the buffers. This can be fixed in
ionic_tx() by changing functions it calls to return void because they
always return 0. For ionic_tx_tso(), there's an actual possibility that
we leave the buffers mapped, so fix this by introducing the helper
function ionic_tx_desc_unmap_bufs(). This function is also re-used
in ionic_tx_clean().

Fixes: 0f3154e6 ("ionic: Add Tx and Rx handling")
Signed-off-by: default avatarBrett Creeley <brett@pensando.io>
Signed-off-by: default avatarShannon Nelson <snelson@pensando.io>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 584fb767

drivers/net/ethernet/pensando/ionic/ionic_txrx.c

+34 −32
Original line number Diff line number Diff line
@@ -669,28 +669,38 @@ static int ionic_tx_map_skb(struct ionic_queue *q, struct sk_buff *skb, 
	return -EIO;

}



static void ionic_tx_clean(struct ionic_queue *q,

			   struct ionic_desc_info *desc_info,

			   struct ionic_cq_info *cq_info,

			   void *cb_arg)

static void ionic_tx_desc_unmap_bufs(struct ionic_queue *q,

				     struct ionic_desc_info *desc_info)

{

	struct ionic_buf_info *buf_info = desc_info->bufs;

	struct ionic_tx_stats *stats = q_to_tx_stats(q);

	struct ionic_qcq *qcq = q_to_qcq(q);

	struct sk_buff *skb = cb_arg;

	struct device *dev = q->dev;

	unsigned int i;

	u16 qi;



	if (desc_info->nbufs) {

	if (!desc_info->nbufs)

		return;



	dma_unmap_single(dev, (dma_addr_t)buf_info->dma_addr,

			 buf_info->len, DMA_TO_DEVICE);

	buf_info++;

	for (i = 1; i < desc_info->nbufs; i++, buf_info++)

		dma_unmap_page(dev, (dma_addr_t)buf_info->dma_addr,

			       buf_info->len, DMA_TO_DEVICE);



	desc_info->nbufs = 0;

}



static void ionic_tx_clean(struct ionic_queue *q,

			   struct ionic_desc_info *desc_info,

			   struct ionic_cq_info *cq_info,

			   void *cb_arg)

{

	struct ionic_tx_stats *stats = q_to_tx_stats(q);

	struct ionic_qcq *qcq = q_to_qcq(q);

	struct sk_buff *skb = cb_arg;

	u16 qi;



	ionic_tx_desc_unmap_bufs(q, desc_info);



	if (!skb)

		return;
@@ -931,8 +941,11 @@ static int ionic_tx_tso(struct ionic_queue *q, struct sk_buff *skb) 
		err = ionic_tx_tcp_inner_pseudo_csum(skb);

	else

		err = ionic_tx_tcp_pseudo_csum(skb);

	if (err)

	if (err) {

		/* clean up mapping from ionic_tx_map_skb */

		ionic_tx_desc_unmap_bufs(q, desc_info);

		return err;

	}



	if (encap)

		hdrlen = skb_inner_transport_header(skb) - skb->data +
@@ -1003,7 +1016,7 @@ static int ionic_tx_tso(struct ionic_queue *q, struct sk_buff *skb) 
	return 0;

}



static int ionic_tx_calc_csum(struct ionic_queue *q, struct sk_buff *skb,

static void ionic_tx_calc_csum(struct ionic_queue *q, struct sk_buff *skb,

			       struct ionic_desc_info *desc_info)

{

	struct ionic_txq_desc *desc = desc_info->txq_desc;
@@ -1038,11 +1051,9 @@ static int ionic_tx_calc_csum(struct ionic_queue *q, struct sk_buff *skb, 
		stats->crc32_csum++;

	else

		stats->csum++;



	return 0;

}



static int ionic_tx_calc_no_csum(struct ionic_queue *q, struct sk_buff *skb,

static void ionic_tx_calc_no_csum(struct ionic_queue *q, struct sk_buff *skb,

				  struct ionic_desc_info *desc_info)

{

	struct ionic_txq_desc *desc = desc_info->txq_desc;
@@ -1074,11 +1085,9 @@ static int ionic_tx_calc_no_csum(struct ionic_queue *q, struct sk_buff *skb, 
	desc->csum_offset = 0;



	stats->csum_none++;



	return 0;

}



static int ionic_tx_skb_frags(struct ionic_queue *q, struct sk_buff *skb,

static void ionic_tx_skb_frags(struct ionic_queue *q, struct sk_buff *skb,

			       struct ionic_desc_info *desc_info)

{

	struct ionic_txq_sg_desc *sg_desc = desc_info->txq_sg_desc;
@@ -1093,31 +1102,24 @@ static int ionic_tx_skb_frags(struct ionic_queue *q, struct sk_buff *skb, 
	}



	stats->frags += skb_shinfo(skb)->nr_frags;



	return 0;

}



static int ionic_tx(struct ionic_queue *q, struct sk_buff *skb)

{

	struct ionic_desc_info *desc_info = &q->info[q->head_idx];

	struct ionic_tx_stats *stats = q_to_tx_stats(q);

	int err;



	if (unlikely(ionic_tx_map_skb(q, skb, desc_info)))

		return -EIO;



	/* set up the initial descriptor */

	if (skb->ip_summed == CHECKSUM_PARTIAL)

		err = ionic_tx_calc_csum(q, skb, desc_info);

		ionic_tx_calc_csum(q, skb, desc_info);

	else

		err = ionic_tx_calc_no_csum(q, skb, desc_info);

	if (err)

		return err;

		ionic_tx_calc_no_csum(q, skb, desc_info);



	/* add frags */

	err = ionic_tx_skb_frags(q, skb, desc_info);

	if (err)

		return err;

	ionic_tx_skb_frags(q, skb, desc_info);



	skb_tx_timestamp(skb);

	stats->pkts++;