Commit bd28df26 authored by Aleksandr Mishin's avatar Aleksandr Mishin Committed by Andrew Lunn
Browse files

octeon_ep: Implement helper for iterating packets in Rx queue 



The common code with some packet and index manipulations is extracted and
moved to newly implemented helper to make the code more readable and avoid
duplication. This is a preparation for skb allocation failure handling.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Suggested-by: default avatarSimon Horman <horms@kernel.org>
Suggested-by: default avatarPaolo Abeni <pabeni@redhat.com>
Signed-off-by: default avatarAleksandr Mishin <amishin@t-argos.ru>
Reviewed-by: default avatarJacob Keller <jacob.e.keller@intel.com>
Signed-off-by: default avatarAndrew Lunn <andrew@lunn.ch>
parent 4ab3e498

drivers/net/ethernet/marvell/octeon_ep/octep_rx.c

+32 −23
Original line number Diff line number Diff line
@@ -336,6 +336,30 @@ static int octep_oq_check_hw_for_pkts(struct octep_device *oct, 
	return new_pkts;

}



/**

 * octep_oq_next_pkt() - Move to the next packet in Rx queue.

 *

 * @oq: Octeon Rx queue data structure.

 * @buff_info: Current packet buffer info.

 * @read_idx: Current packet index in the ring.

 * @desc_used: Current packet descriptor number.

 *

 * Free the resources associated with a packet.

 * Increment packet index in the ring and packet descriptor number.

 */

static void octep_oq_next_pkt(struct octep_oq *oq,

			      struct octep_rx_buffer *buff_info,

			      u32 *read_idx, u32 *desc_used)

{

	dma_unmap_page(oq->dev, oq->desc_ring[*read_idx].buffer_ptr,

		       PAGE_SIZE, DMA_FROM_DEVICE);

	buff_info->page = NULL;

	(*read_idx)++;

	(*desc_used)++;

	if (*read_idx == oq->max_count)

		*read_idx = 0;

}



/**

 * __octep_oq_process_rx() - Process hardware Rx queue and push to stack.

 *
@@ -367,10 +391,7 @@ static int __octep_oq_process_rx(struct octep_device *oct, 
	desc_used = 0;

	for (pkt = 0; pkt < pkts_to_process; pkt++) {

		buff_info = (struct octep_rx_buffer *)&oq->buff_info[read_idx];

		dma_unmap_page(oq->dev, oq->desc_ring[read_idx].buffer_ptr,

			       PAGE_SIZE, DMA_FROM_DEVICE);

		resp_hw = page_address(buff_info->page);

		buff_info->page = NULL;



		/* Swap the length field that is in Big-Endian to CPU */

		buff_info->len = be64_to_cpu(resp_hw->length);
@@ -394,36 +415,27 @@ static int __octep_oq_process_rx(struct octep_device *oct, 
			data_offset = OCTEP_OQ_RESP_HW_SIZE;

			rx_ol_flags = 0;

		}

		rx_bytes += buff_info->len;



		if (buff_info->len <= oq->max_single_buffer_size) {

		octep_oq_next_pkt(oq, buff_info, &read_idx, &desc_used);



		skb = build_skb((void *)resp_hw, PAGE_SIZE);

		skb_reserve(skb, data_offset);



		rx_bytes += buff_info->len;



		if (buff_info->len <= oq->max_single_buffer_size) {

			skb_put(skb, buff_info->len);

			read_idx++;

			desc_used++;

			if (read_idx == oq->max_count)

				read_idx = 0;

		} else {

			struct skb_shared_info *shinfo;

			u16 data_len;



			skb = build_skb((void *)resp_hw, PAGE_SIZE);

			skb_reserve(skb, data_offset);

			/* Head fragment includes response header(s);

			 * subsequent fragments contains only data.

			 */

			skb_put(skb, oq->max_single_buffer_size);

			read_idx++;

			desc_used++;

			if (read_idx == oq->max_count)

				read_idx = 0;



			shinfo = skb_shinfo(skb);

			data_len = buff_info->len - oq->max_single_buffer_size;

			while (data_len) {

				dma_unmap_page(oq->dev, oq->desc_ring[read_idx].buffer_ptr,

					       PAGE_SIZE, DMA_FROM_DEVICE);

				buff_info = (struct octep_rx_buffer *)

					    &oq->buff_info[read_idx];

				if (data_len < oq->buffer_size) {
@@ -438,11 +450,8 @@ static int __octep_oq_process_rx(struct octep_device *oct, 
						buff_info->page, 0,

						buff_info->len,

						buff_info->len);

				buff_info->page = NULL;

				read_idx++;

				desc_used++;

				if (read_idx == oq->max_count)

					read_idx = 0;



				octep_oq_next_pkt(oq, buff_info, &read_idx, &desc_used);

			}

		}