Commit 6366ad33 authored by Alexander Duyck's avatar Alexander Duyck Committed by David S. Miller
Browse files

igb: remove use of skb_dma_map from driver 



This change removes skb_dma_map/unmap calls from the igb driver due to the
fact that the call is incompatible with iommu enabled kernels.  In order to
prevent warnings about using the wrong unmap call I have added a
mapped_as_page value to the buffer_info structure to track if the mapped
region is a page or a buffer.

Signed-off-by: default avatarAlexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: default avatarJeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent e5a43549

drivers/net/igb/igb.h

+3 −2
Original line number Diff line number Diff line
@@ -137,12 +137,13 @@ struct igb_buffer { 
			unsigned long time_stamp;

			u16 length;

			u16 next_to_watch;

			u16 mapped_as_page;

		};

		/* RX */

		struct {

			struct page *page;

			u64 page_dma;

			unsigned int page_offset;

			dma_addr_t page_dma;

			u16 page_offset;

		};

	};

};

drivers/net/igb/igb_main.c

+53 −16
Original line number Diff line number Diff line
@@ -2654,16 +2654,27 @@ static void igb_free_all_tx_resources(struct igb_adapter *adapter) 
void igb_unmap_and_free_tx_resource(struct igb_ring *tx_ring,

				    struct igb_buffer *buffer_info)

{

	if (buffer_info->dma) {

		if (buffer_info->mapped_as_page)

			pci_unmap_page(tx_ring->pdev,

					buffer_info->dma,

					buffer_info->length,

					PCI_DMA_TODEVICE);

		else

			pci_unmap_single(tx_ring->pdev,

					buffer_info->dma,

					buffer_info->length,

					PCI_DMA_TODEVICE);

		buffer_info->dma = 0;

	}

	if (buffer_info->skb) {

		skb_dma_unmap(&tx_ring->pdev->dev,

		              buffer_info->skb,

		              DMA_TO_DEVICE);

		dev_kfree_skb_any(buffer_info->skb);

		buffer_info->skb = NULL;

	}

	buffer_info->time_stamp = 0;

	/* buffer_info must be completely set up in the transmit path */

	buffer_info->length = 0;

	buffer_info->next_to_watch = 0;

	buffer_info->mapped_as_page = false;

}



/**
@@ -3561,24 +3572,19 @@ static inline int igb_tx_map_adv(struct igb_ring *tx_ring, struct sk_buff *skb, 
	unsigned int len = skb_headlen(skb);

	unsigned int count = 0, i;

	unsigned int f;

	dma_addr_t *map;



	i = tx_ring->next_to_use;



	if (skb_dma_map(&pdev->dev, skb, DMA_TO_DEVICE)) {

		dev_err(&pdev->dev, "TX DMA map failed\n");

		return 0;

	}



	map = skb_shinfo(skb)->dma_maps;



	buffer_info = &tx_ring->buffer_info[i];

	BUG_ON(len >= IGB_MAX_DATA_PER_TXD);

	buffer_info->length = len;

	/* set time_stamp *before* dma to help avoid a possible race */

	buffer_info->time_stamp = jiffies;

	buffer_info->next_to_watch = i;

	buffer_info->dma = skb_shinfo(skb)->dma_head;

	buffer_info->dma = pci_map_single(pdev, skb->data, len,

					  PCI_DMA_TODEVICE);

	if (pci_dma_mapping_error(pdev, buffer_info->dma))

		goto dma_error;



	for (f = 0; f < skb_shinfo(skb)->nr_frags; f++) {

		struct skb_frag_struct *frag;
@@ -3595,7 +3601,15 @@ static inline int igb_tx_map_adv(struct igb_ring *tx_ring, struct sk_buff *skb, 
		buffer_info->length = len;

		buffer_info->time_stamp = jiffies;

		buffer_info->next_to_watch = i;

		buffer_info->dma = map[count];

		buffer_info->mapped_as_page = true;

		buffer_info->dma = pci_map_page(pdev,

						frag->page,

						frag->page_offset,

						len,

						PCI_DMA_TODEVICE);

		if (pci_dma_mapping_error(pdev, buffer_info->dma))

			goto dma_error;



		count++;

	}
@@ -3603,6 +3617,29 @@ static inline int igb_tx_map_adv(struct igb_ring *tx_ring, struct sk_buff *skb, 
	tx_ring->buffer_info[first].next_to_watch = i;



	return ++count;



dma_error:

	dev_err(&pdev->dev, "TX DMA map failed\n");



	/* clear timestamp and dma mappings for failed buffer_info mapping */

	buffer_info->dma = 0;

	buffer_info->time_stamp = 0;

	buffer_info->length = 0;

	buffer_info->next_to_watch = 0;

	buffer_info->mapped_as_page = false;

	count--;



	/* clear timestamp and dma mappings for remaining portion of packet */

	while (count >= 0) {

		count--;

		i--;

		if (i < 0)

			i += tx_ring->count;

		buffer_info = &tx_ring->buffer_info[i];

		igb_unmap_and_free_tx_resource(tx_ring, buffer_info);

	}



	return 0;

}



static inline void igb_tx_queue_adv(struct igb_ring *tx_ring,
@@ -3755,7 +3792,7 @@ netdev_tx_t igb_xmit_frame_ring_adv(struct sk_buff *skb, 
	 * has occured and we need to rewind the descriptor queue

	 */

	count = igb_tx_map_adv(tx_ring, skb, first);

	if (count <= 0) {

	if (!count) {

		dev_kfree_skb_any(skb);

		tx_ring->buffer_info[first].time_stamp = 0;

		tx_ring->next_to_use = first;