1 files changed, 938 insertions, 0 deletions

diff --git a/drivers/net/ethernet/intel/fm10k/fm10k_main.c b/drivers/net/ethernet/intel/fm10k/fm10k_main.c
index bf84c263df0e..f7220d841336 100644
--- a/drivers/net/ethernet/intel/fm10k/fm10k_main.c
+++ b/drivers/net/ethernet/intel/fm10k/fm10k_main.c
@@ -24,6 +24,7 @@
 #include <net/ip.h>
 #include <net/tcp.h>
 #include <linux/if_macvlan.h>
+#include <linux/prefetch.h>
 
 #include "fm10k.h"
 
@@ -67,6 +68,921 @@ static void __exit fm10k_exit_module(void)
 }
 module_exit(fm10k_exit_module);
 
+static bool fm10k_alloc_mapped_page(struct fm10k_ring *rx_ring,
+				    struct fm10k_rx_buffer *bi)
+{
+	struct page *page = bi->page;
+	dma_addr_t dma;
+
+	/* Only page will be NULL if buffer was consumed */
+	if (likely(page))
+		return true;
+
+	/* alloc new page for storage */
+	page = alloc_page(GFP_ATOMIC | __GFP_COLD);
+	if (unlikely(!page)) {
+		rx_ring->rx_stats.alloc_failed++;
+		return false;
+	}
+
+	/* map page for use */
+	dma = dma_map_page(rx_ring->dev, page, 0, PAGE_SIZE, DMA_FROM_DEVICE);
+
+	/* if mapping failed free memory back to system since
+	 * there isn't much point in holding memory we can't use
+	 */
+	if (dma_mapping_error(rx_ring->dev, dma)) {
+		__free_page(page);
+		bi->page = NULL;
+
+		rx_ring->rx_stats.alloc_failed++;
+		return false;
+	}
+
+	bi->dma = dma;
+	bi->page = page;
+	bi->page_offset = 0;
+
+	return true;
+}
+
+/**
+ * fm10k_alloc_rx_buffers - Replace used receive buffers
+ * @rx_ring: ring to place buffers on
+ * @cleaned_count: number of buffers to replace
+ **/
+void fm10k_alloc_rx_buffers(struct fm10k_ring *rx_ring, u16 cleaned_count)
+{
+	union fm10k_rx_desc *rx_desc;
+	struct fm10k_rx_buffer *bi;
+	u16 i = rx_ring->next_to_use;
+
+	/* nothing to do */
+	if (!cleaned_count)
+		return;
+
+	rx_desc = FM10K_RX_DESC(rx_ring, i);
+	bi = &rx_ring->rx_buffer[i];
+	i -= rx_ring->count;
+
+	do {
+		if (!fm10k_alloc_mapped_page(rx_ring, bi))
+			break;
+
+		/* Refresh the desc even if buffer_addrs didn't change
+		 * because each write-back erases this info.
+		 */
+		rx_desc->q.pkt_addr = cpu_to_le64(bi->dma + bi->page_offset);
+
+		rx_desc++;
+		bi++;
+		i++;
+		if (unlikely(!i)) {
+			rx_desc = FM10K_RX_DESC(rx_ring, 0);
+			bi = rx_ring->rx_buffer;
+			i -= rx_ring->count;
+		}
+
+		/* clear the hdr_addr for the next_to_use descriptor */
+		rx_desc->q.hdr_addr = 0;
+
+		cleaned_count--;
+	} while (cleaned_count);
+
+	i += rx_ring->count;
+
+	if (rx_ring->next_to_use != i) {
+		/* record the next descriptor to use */
+		rx_ring->next_to_use = i;
+
+		/* update next to alloc since we have filled the ring */
+		rx_ring->next_to_alloc = i;
+
+		/* Force memory writes to complete before letting h/w
+		 * know there are new descriptors to fetch.  (Only
+		 * applicable for weak-ordered memory model archs,
+		 * such as IA-64).
+		 */
+		wmb();
+
+		/* notify hardware of new descriptors */
+		writel(i, rx_ring->tail);
+	}
+}
+
+/**
+ * fm10k_reuse_rx_page - page flip buffer and store it back on the ring
+ * @rx_ring: rx descriptor ring to store buffers on
+ * @old_buff: donor buffer to have page reused
+ *
+ * Synchronizes page for reuse by the interface
+ **/
+static void fm10k_reuse_rx_page(struct fm10k_ring *rx_ring,
+				struct fm10k_rx_buffer *old_buff)
+{
+	struct fm10k_rx_buffer *new_buff;
+	u16 nta = rx_ring->next_to_alloc;
+
+	new_buff = &rx_ring->rx_buffer[nta];
+
+	/* update, and store next to alloc */
+	nta++;
+	rx_ring->next_to_alloc = (nta < rx_ring->count) ? nta : 0;
+
+	/* transfer page from old buffer to new buffer */
+	memcpy(new_buff, old_buff, sizeof(struct fm10k_rx_buffer));
+
+	/* sync the buffer for use by the device */
+	dma_sync_single_range_for_device(rx_ring->dev, old_buff->dma,
+					 old_buff->page_offset,
+					 FM10K_RX_BUFSZ,
+					 DMA_FROM_DEVICE);
+}
+
+static bool fm10k_can_reuse_rx_page(struct fm10k_rx_buffer *rx_buffer,
+				    struct page *page,
+				    unsigned int truesize)
+{
+	/* avoid re-using remote pages */
+	if (unlikely(page_to_nid(page) != numa_mem_id()))
+		return false;
+
+#if (PAGE_SIZE < 8192)
+	/* if we are only owner of page we can reuse it */
+	if (unlikely(page_count(page) != 1))
+		return false;
+
+	/* flip page offset to other buffer */
+	rx_buffer->page_offset ^= FM10K_RX_BUFSZ;
+
+	/* since we are the only owner of the page and we need to
+	 * increment it, just set the value to 2 in order to avoid
+	 * an unnecessary locked operation
+	 */
+	atomic_set(&page->_count, 2);
+#else
+	/* move offset up to the next cache line */
+	rx_buffer->page_offset += truesize;
+
+	if (rx_buffer->page_offset > (PAGE_SIZE - FM10K_RX_BUFSZ))
+		return false;
+
+	/* bump ref count on page before it is given to the stack */
+	get_page(page);
+#endif
+
+	return true;
+}
+
+/**
+ * fm10k_add_rx_frag - Add contents of Rx buffer to sk_buff
+ * @rx_ring: rx descriptor ring to transact packets on
+ * @rx_buffer: buffer containing page to add
+ * @rx_desc: descriptor containing length of buffer written by hardware
+ * @skb: sk_buff to place the data into
+ *
+ * This function will add the data contained in rx_buffer->page to the skb.
+ * This is done either through a direct copy if the data in the buffer is
+ * less than the skb header size, otherwise it will just attach the page as
+ * a frag to the skb.
+ *
+ * The function will then update the page offset if necessary and return
+ * true if the buffer can be reused by the interface.
+ **/
+static bool fm10k_add_rx_frag(struct fm10k_ring *rx_ring,
+			      struct fm10k_rx_buffer *rx_buffer,
+			      union fm10k_rx_desc *rx_desc,
+			      struct sk_buff *skb)
+{
+	struct page *page = rx_buffer->page;
+	unsigned int size = le16_to_cpu(rx_desc->w.length);
+#if (PAGE_SIZE < 8192)
+	unsigned int truesize = FM10K_RX_BUFSZ;
+#else
+	unsigned int truesize = ALIGN(size, L1_CACHE_BYTES);
+#endif
+
+	if ((size <= FM10K_RX_HDR_LEN) && !skb_is_nonlinear(skb)) {
+		unsigned char *va = page_address(page) + rx_buffer->page_offset;
+
+		memcpy(__skb_put(skb, size), va, ALIGN(size, sizeof(long)));
+
+		/* we can reuse buffer as-is, just make sure it is local */
+		if (likely(page_to_nid(page) == numa_mem_id()))
+			return true;
+
+		/* this page cannot be reused so discard it */
+		put_page(page);
+		return false;
+	}
+
+	skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page,
+			rx_buffer->page_offset, size, truesize);
+
+	return fm10k_can_reuse_rx_page(rx_buffer, page, truesize);
+}
+
+static struct sk_buff *fm10k_fetch_rx_buffer(struct fm10k_ring *rx_ring,
+					     union fm10k_rx_desc *rx_desc,
+					     struct sk_buff *skb)
+{
+	struct fm10k_rx_buffer *rx_buffer;
+	struct page *page;
+
+	rx_buffer = &rx_ring->rx_buffer[rx_ring->next_to_clean];
+
+	page = rx_buffer->page;
+	prefetchw(page);
+
+	if (likely(!skb)) {
+		void *page_addr = page_address(page) +
+				  rx_buffer->page_offset;
+
+		/* prefetch first cache line of first page */
+		prefetch(page_addr);
+#if L1_CACHE_BYTES < 128
+		prefetch(page_addr + L1_CACHE_BYTES);
+#endif
+
+		/* allocate a skb to store the frags */
+		skb = netdev_alloc_skb_ip_align(rx_ring->netdev,
+						FM10K_RX_HDR_LEN);
+		if (unlikely(!skb)) {
+			rx_ring->rx_stats.alloc_failed++;
+			return NULL;
+		}
+
+		/* we will be copying header into skb->data in
+		 * pskb_may_pull so it is in our interest to prefetch
+		 * it now to avoid a possible cache miss
+		 */
+		prefetchw(skb->data);
+	}
+
+	/* we are reusing so sync this buffer for CPU use */
+	dma_sync_single_range_for_cpu(rx_ring->dev,
+				      rx_buffer->dma,
+				      rx_buffer->page_offset,
+				      FM10K_RX_BUFSZ,
+				      DMA_FROM_DEVICE);
+
+	/* pull page into skb */
+	if (fm10k_add_rx_frag(rx_ring, rx_buffer, rx_desc, skb)) {
+		/* hand second half of page back to the ring */
+		fm10k_reuse_rx_page(rx_ring, rx_buffer);
+	} else {
+		/* we are not reusing the buffer so unmap it */
+		dma_unmap_page(rx_ring->dev, rx_buffer->dma,
+			       PAGE_SIZE, DMA_FROM_DEVICE);
+	}
+
+	/* clear contents of rx_buffer */
+	rx_buffer->page = NULL;
+
+	return skb;
+}
+
+/**
+ * fm10k_process_skb_fields - Populate skb header fields from Rx descriptor
+ * @rx_ring: rx descriptor ring packet is being transacted on
+ * @rx_desc: pointer to the EOP Rx descriptor
+ * @skb: pointer to current skb being populated
+ *
+ * This function checks the ring, descriptor, and packet information in
+ * order to populate the hash, checksum, VLAN, timestamp, protocol, and
+ * other fields within the skb.
+ **/
+static unsigned int fm10k_process_skb_fields(struct fm10k_ring *rx_ring,
+					     union fm10k_rx_desc *rx_desc,
+					     struct sk_buff *skb)
+{
+	unsigned int len = skb->len;
+
+	FM10K_CB(skb)->fi.w.vlan = rx_desc->w.vlan;
+
+	skb_record_rx_queue(skb, rx_ring->queue_index);
+
+	FM10K_CB(skb)->fi.d.glort = rx_desc->d.glort;
+
+	if (rx_desc->w.vlan) {
+		u16 vid = le16_to_cpu(rx_desc->w.vlan);
+
+		if (vid != rx_ring->vid)
+			__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), vid);
+	}
+
+	skb->protocol = eth_type_trans(skb, rx_ring->netdev);
+
+	return len;
+}
+
+/**
+ * fm10k_is_non_eop - process handling of non-EOP buffers
+ * @rx_ring: Rx ring being processed
+ * @rx_desc: Rx descriptor for current buffer
+ *
+ * This function updates next to clean.  If the buffer is an EOP buffer
+ * this function exits returning false, otherwise it will place the
+ * sk_buff in the next buffer to be chained and return true indicating
+ * that this is in fact a non-EOP buffer.
+ **/
+static bool fm10k_is_non_eop(struct fm10k_ring *rx_ring,
+			     union fm10k_rx_desc *rx_desc)
+{
+	u32 ntc = rx_ring->next_to_clean + 1;
+
+	/* fetch, update, and store next to clean */
+	ntc = (ntc < rx_ring->count) ? ntc : 0;
+	rx_ring->next_to_clean = ntc;
+
+	prefetch(FM10K_RX_DESC(rx_ring, ntc));
+
+	if (likely(fm10k_test_staterr(rx_desc, FM10K_RXD_STATUS_EOP)))
+		return false;
+
+	return true;
+}
+
+/**
+ * fm10k_pull_tail - fm10k specific version of skb_pull_tail
+ * @rx_ring: rx descriptor ring packet is being transacted on
+ * @rx_desc: pointer to the EOP Rx descriptor
+ * @skb: pointer to current skb being adjusted
+ *
+ * This function is an fm10k specific version of __pskb_pull_tail.  The
+ * main difference between this version and the original function is that
+ * this function can make several assumptions about the state of things
+ * that allow for significant optimizations versus the standard function.
+ * As a result we can do things like drop a frag and maintain an accurate
+ * truesize for the skb.
+ */
+static void fm10k_pull_tail(struct fm10k_ring *rx_ring,
+			    union fm10k_rx_desc *rx_desc,
+			    struct sk_buff *skb)
+{
+	struct skb_frag_struct *frag = &skb_shinfo(skb)->frags[0];
+	unsigned char *va;
+	unsigned int pull_len;
+
+	/* it is valid to use page_address instead of kmap since we are
+	 * working with pages allocated out of the lomem pool per
+	 * alloc_page(GFP_ATOMIC)
+	 */
+	va = skb_frag_address(frag);
+
+	/* we need the header to contain the greater of either ETH_HLEN or
+	 * 60 bytes if the skb->len is less than 60 for skb_pad.
+	 */
+	pull_len = eth_get_headlen(va, FM10K_RX_HDR_LEN);
+
+	/* align pull length to size of long to optimize memcpy performance */
+	skb_copy_to_linear_data(skb, va, ALIGN(pull_len, sizeof(long)));
+
+	/* update all of the pointers */
+	skb_frag_size_sub(frag, pull_len);
+	frag->page_offset += pull_len;
+	skb->data_len -= pull_len;
+	skb->tail += pull_len;
+}
+
+/**
+ * fm10k_cleanup_headers - Correct corrupted or empty headers
+ * @rx_ring: rx descriptor ring packet is being transacted on
+ * @rx_desc: pointer to the EOP Rx descriptor
+ * @skb: pointer to current skb being fixed
+ *
+ * Address the case where we are pulling data in on pages only
+ * and as such no data is present in the skb header.
+ *
+ * In addition if skb is not at least 60 bytes we need to pad it so that
+ * it is large enough to qualify as a valid Ethernet frame.
+ *
+ * Returns true if an error was encountered and skb was freed.
+ **/
+static bool fm10k_cleanup_headers(struct fm10k_ring *rx_ring,
+				  union fm10k_rx_desc *rx_desc,
+				  struct sk_buff *skb)
+{
+	if (unlikely((fm10k_test_staterr(rx_desc,
+					 FM10K_RXD_STATUS_RXE)))) {
+		dev_kfree_skb_any(skb);
+		rx_ring->rx_stats.errors++;
+		return true;
+	}
+
+	/* place header in linear portion of buffer */
+	if (skb_is_nonlinear(skb))
+		fm10k_pull_tail(rx_ring, rx_desc, skb);
+
+	/* if skb_pad returns an error the skb was freed */
+	if (unlikely(skb->len < 60)) {
+		int pad_len = 60 - skb->len;
+
+		if (skb_pad(skb, pad_len))
+			return true;
+		__skb_put(skb, pad_len);
+	}
+
+	return false;
+}
+
+/**
+ * fm10k_receive_skb - helper function to handle rx indications
+ * @q_vector: structure containing interrupt and ring information
+ * @skb: packet to send up
+ **/
+static void fm10k_receive_skb(struct fm10k_q_vector *q_vector,
+			      struct sk_buff *skb)
+{
+	napi_gro_receive(&q_vector->napi, skb);
+}
+
+static bool fm10k_clean_rx_irq(struct fm10k_q_vector *q_vector,
+			       struct fm10k_ring *rx_ring,
+			       int budget)
+{
+	struct sk_buff *skb = rx_ring->skb;
+	unsigned int total_bytes = 0, total_packets = 0;
+	u16 cleaned_count = fm10k_desc_unused(rx_ring);
+
+	do {
+		union fm10k_rx_desc *rx_desc;
+
+		/* return some buffers to hardware, one at a time is too slow */
+		if (cleaned_count >= FM10K_RX_BUFFER_WRITE) {
+			fm10k_alloc_rx_buffers(rx_ring, cleaned_count);
+			cleaned_count = 0;
+		}
+
+		rx_desc = FM10K_RX_DESC(rx_ring, rx_ring->next_to_clean);
+
+		if (!fm10k_test_staterr(rx_desc, FM10K_RXD_STATUS_DD))
+			break;
+
+		/* This memory barrier is needed to keep us from reading
+		 * any other fields out of the rx_desc until we know the
+		 * RXD_STATUS_DD bit is set
+		 */
+		rmb();
+
+		/* retrieve a buffer from the ring */
+		skb = fm10k_fetch_rx_buffer(rx_ring, rx_desc, skb);
+
+		/* exit if we failed to retrieve a buffer */
+		if (!skb)
+			break;
+
+		cleaned_count++;
+
+		/* fetch next buffer in frame if non-eop */
+		if (fm10k_is_non_eop(rx_ring, rx_desc))
+			continue;
+
+		/* verify the packet layout is correct */
+		if (fm10k_cleanup_headers(rx_ring, rx_desc, skb)) {
+			skb = NULL;
+			continue;
+		}
+
+		/* populate checksum, timestamp, VLAN, and protocol */
+		total_bytes += fm10k_process_skb_fields(rx_ring, rx_desc, skb);
+
+		fm10k_receive_skb(q_vector, skb);
+
+		/* reset skb pointer */
+		skb = NULL;
+
+		/* update budget accounting */
+		total_packets++;
+	} while (likely(total_packets < budget));
+
+	/* place incomplete frames back on ring for completion */
+	rx_ring->skb = skb;
+
+	u64_stats_update_begin(&rx_ring->syncp);
+	rx_ring->stats.packets += total_packets;
+	rx_ring->stats.bytes += total_bytes;
+	u64_stats_update_end(&rx_ring->syncp);
+	q_vector->rx.total_packets += total_packets;
+	q_vector->rx.total_bytes += total_bytes;
+
+	return total_packets < budget;
+}
+
+static bool fm10k_tx_desc_push(struct fm10k_ring *tx_ring,
+			       struct fm10k_tx_desc *tx_desc, u16 i,
+			       dma_addr_t dma, unsigned int size, u8 desc_flags)
+{
+	/* set RS and INT for last frame in a cache line */
+	if ((++i & (FM10K_TXD_WB_FIFO_SIZE - 1)) == 0)
+		desc_flags |= FM10K_TXD_FLAG_RS | FM10K_TXD_FLAG_INT;
+
+	/* record values to descriptor */
+	tx_desc->buffer_addr = cpu_to_le64(dma);
+	tx_desc->flags = desc_flags;
+	tx_desc->buflen = cpu_to_le16(size);
+
+	/* return true if we just wrapped the ring */
+	return i == tx_ring->count;
+}
+
+static void fm10k_tx_map(struct fm10k_ring *tx_ring,
+			 struct fm10k_tx_buffer *first)
+{
+	struct sk_buff *skb = first->skb;
+	struct fm10k_tx_buffer *tx_buffer;
+	struct fm10k_tx_desc *tx_desc;
+	struct skb_frag_struct *frag;
+	unsigned char *data;
+	dma_addr_t dma;
+	unsigned int data_len, size;
+	u16 i = tx_ring->next_to_use;
+	u8 flags = 0;
+
+	tx_desc = FM10K_TX_DESC(tx_ring, i);
+
+	/* add HW VLAN tag */
+	if (vlan_tx_tag_present(skb))
+		tx_desc->vlan = cpu_to_le16(vlan_tx_tag_get(skb));
+	else
+		tx_desc->vlan = 0;
+
+	size = skb_headlen(skb);
+	data = skb->data;
+
+	dma = dma_map_single(tx_ring->dev, data, size, DMA_TO_DEVICE);
+
+	data_len = skb->data_len;
+	tx_buffer = first;
+
+	for (frag = &skb_shinfo(skb)->frags[0];; frag++) {
+		if (dma_mapping_error(tx_ring->dev, dma))
+			goto dma_error;
+
+		/* record length, and DMA address */
+		dma_unmap_len_set(tx_buffer, len, size);
+		dma_unmap_addr_set(tx_buffer, dma, dma);
+
+		while (unlikely(size > FM10K_MAX_DATA_PER_TXD)) {
+			if (fm10k_tx_desc_push(tx_ring, tx_desc++, i++, dma,
+					       FM10K_MAX_DATA_PER_TXD, flags)) {
+				tx_desc = FM10K_TX_DESC(tx_ring, 0);
+				i = 0;
+			}
+
+			dma += FM10K_MAX_DATA_PER_TXD;
+			size -= FM10K_MAX_DATA_PER_TXD;
+		}
+
+		if (likely(!data_len))
+			break;
+
+		if (fm10k_tx_desc_push(tx_ring, tx_desc++, i++,
+				       dma, size, flags)) {
+			tx_desc = FM10K_TX_DESC(tx_ring, 0);
+			i = 0;
+		}
+
+		size = skb_frag_size(frag);
+		data_len -= size;
+
+		dma = skb_frag_dma_map(tx_ring->dev, frag, 0, size,
+				       DMA_TO_DEVICE);
+
+		tx_buffer = &tx_ring->tx_buffer[i];
+	}
+
+	/* write last descriptor with LAST bit set */
+	flags |= FM10K_TXD_FLAG_LAST;
+
+	if (fm10k_tx_desc_push(tx_ring, tx_desc, i++, dma, size, flags))
+		i = 0;
+
+	/* record bytecount for BQL */
+	netdev_tx_sent_queue(txring_txq(tx_ring), first->bytecount);
+
+	/* record SW timestamp if HW timestamp is not available */
+	skb_tx_timestamp(first->skb);
+
+	/* Force memory writes to complete before letting h/w know there
+	 * are new descriptors to fetch.  (Only applicable for weak-ordered
+	 * memory model archs, such as IA-64).
+	 *
+	 * We also need this memory barrier to make certain all of the
+	 * status bits have been updated before next_to_watch is written.
+	 */
+	wmb();
+
+	/* set next_to_watch value indicating a packet is present */
+	first->next_to_watch = tx_desc;
+
+	tx_ring->next_to_use = i;
+
+	/* notify HW of packet */
+	writel(i, tx_ring->tail);
+
+	/* we need this if more than one processor can write to our tail
+	 * at a time, it synchronizes IO on IA64/Altix systems
+	 */
+	mmiowb();
+
+	return;
+dma_error:
+	dev_err(tx_ring->dev, "TX DMA map failed\n");
+
+	/* clear dma mappings for failed tx_buffer map */
+	for (;;) {
+		tx_buffer = &tx_ring->tx_buffer[i];
+		fm10k_unmap_and_free_tx_resource(tx_ring, tx_buffer);
+		if (tx_buffer == first)
+			break;
+		if (i == 0)
+			i = tx_ring->count;
+		i--;
+	}
+
+	tx_ring->next_to_use = i;
+}
+
+static int __fm10k_maybe_stop_tx(struct fm10k_ring *tx_ring, u16 size)
+{
+	netif_stop_subqueue(tx_ring->netdev, tx_ring->queue_index);
+
+	smp_mb();
+
+	/* We need to check again in a case another CPU has just
+	 * made room available. */
+	if (likely(fm10k_desc_unused(tx_ring) < size))
+		return -EBUSY;
+
+	/* A reprieve! - use start_queue because it doesn't call schedule */
+	netif_start_subqueue(tx_ring->netdev, tx_ring->queue_index);
+	++tx_ring->tx_stats.restart_queue;
+	return 0;
+}
+
+static inline int fm10k_maybe_stop_tx(struct fm10k_ring *tx_ring, u16 size)
+{
+	if (likely(fm10k_desc_unused(tx_ring) >= size))
+		return 0;
+	return __fm10k_maybe_stop_tx(tx_ring, size);
+}
+
+netdev_tx_t fm10k_xmit_frame_ring(struct sk_buff *skb,
+				  struct fm10k_ring *tx_ring)
+{
+	struct fm10k_tx_buffer *first;
+	u32 tx_flags = 0;
+#if PAGE_SIZE > FM10K_MAX_DATA_PER_TXD
+	unsigned short f;
+#endif
+	u16 count = TXD_USE_COUNT(skb_headlen(skb));
+
+	/* need: 1 descriptor per page * PAGE_SIZE/FM10K_MAX_DATA_PER_TXD,
+	 *       + 1 desc for skb_headlen/FM10K_MAX_DATA_PER_TXD,
+	 *       + 2 desc gap to keep tail from touching head
+	 * otherwise try next time
+	 */
+#if PAGE_SIZE > FM10K_MAX_DATA_PER_TXD
+	for (f = 0; f < skb_shinfo(skb)->nr_frags; f++)
+		count += TXD_USE_COUNT(skb_shinfo(skb)->frags[f].size);
+#else
+	count += skb_shinfo(skb)->nr_frags;
+#endif
+	if (fm10k_maybe_stop_tx(tx_ring, count + 3)) {
+		tx_ring->tx_stats.tx_busy++;
+		return NETDEV_TX_BUSY;
+	}
+
+	/* record the location of the first descriptor for this packet */
+	first = &tx_ring->tx_buffer[tx_ring->next_to_use];
+	first->skb = skb;
+	first->bytecount = max_t(unsigned int, skb->len, ETH_ZLEN);
+	first->gso_segs = 1;
+
+	/* record initial flags and protocol */
+	first->tx_flags = tx_flags;
+
+	fm10k_tx_map(tx_ring, first);
+
+	fm10k_maybe_stop_tx(tx_ring, DESC_NEEDED);
+
+	return NETDEV_TX_OK;
+}
+
+static u64 fm10k_get_tx_completed(struct fm10k_ring *ring)
+{
+	return ring->stats.packets;
+}
+
+static u64 fm10k_get_tx_pending(struct fm10k_ring *ring)
+{
+	/* use SW head and tail until we have real hardware */
+	u32 head = ring->next_to_clean;
+	u32 tail = ring->next_to_use;
+
+	return ((head <= tail) ? tail : tail + ring->count) - head;
+}
+
+bool fm10k_check_tx_hang(struct fm10k_ring *tx_ring)
+{
+	u32 tx_done = fm10k_get_tx_completed(tx_ring);
+	u32 tx_done_old = tx_ring->tx_stats.tx_done_old;
+	u32 tx_pending = fm10k_get_tx_pending(tx_ring);
+
+	clear_check_for_tx_hang(tx_ring);
+
+	/* Check for a hung queue, but be thorough. This verifies
+	 * that a transmit has been completed since the previous
+	 * check AND there is at least one packet pending. By
+	 * requiring this to fail twice we avoid races with
+	 * clearing the ARMED bit and conditions where we
+	 * run the check_tx_hang logic with a transmit completion
+	 * pending but without time to complete it yet.
+	 */
+	if (!tx_pending || (tx_done_old != tx_done)) {
+		/* update completed stats and continue */
+		tx_ring->tx_stats.tx_done_old = tx_done;
+		/* reset the countdown */
+		clear_bit(__FM10K_HANG_CHECK_ARMED, &tx_ring->state);
+
+		return false;
+	}
+
+	/* make sure it is true for two checks in a row */
+	return test_and_set_bit(__FM10K_HANG_CHECK_ARMED, &tx_ring->state);
+}
+
+/**
+ * fm10k_tx_timeout_reset - initiate reset due to Tx timeout
+ * @interface: driver private struct
+ **/
+void fm10k_tx_timeout_reset(struct fm10k_intfc *interface)
+{
+	/* Do the reset outside of interrupt context */
+	if (!test_bit(__FM10K_DOWN, &interface->state)) {
+		netdev_err(interface->netdev, "Reset interface\n");
+		interface->tx_timeout_count++;
+		interface->flags |= FM10K_FLAG_RESET_REQUESTED;
+		fm10k_service_event_schedule(interface);
+	}
+}
+
+/**
+ * fm10k_clean_tx_irq - Reclaim resources after transmit completes
+ * @q_vector: structure containing interrupt and ring information
+ * @tx_ring: tx ring to clean
+ **/
+static bool fm10k_clean_tx_irq(struct fm10k_q_vector *q_vector,
+			       struct fm10k_ring *tx_ring)
+{
+	struct fm10k_intfc *interface = q_vector->interface;
+	struct fm10k_tx_buffer *tx_buffer;
+	struct fm10k_tx_desc *tx_desc;
+	unsigned int total_bytes = 0, total_packets = 0;
+	unsigned int budget = q_vector->tx.work_limit;
+	unsigned int i = tx_ring->next_to_clean;
+
+	if (test_bit(__FM10K_DOWN, &interface->state))
+		return true;
+
+	tx_buffer = &tx_ring->tx_buffer[i];
+	tx_desc = FM10K_TX_DESC(tx_ring, i);
+	i -= tx_ring->count;
+
+	do {
+		struct fm10k_tx_desc *eop_desc = tx_buffer->next_to_watch;
+
+		/* if next_to_watch is not set then there is no work pending */
+		if (!eop_desc)
+			break;
+
+		/* prevent any other reads prior to eop_desc */
+		read_barrier_depends();
+
+		/* if DD is not set pending work has not been completed */
+		if (!(eop_desc->flags & FM10K_TXD_FLAG_DONE))
+			break;
+
+		/* clear next_to_watch to prevent false hangs */
+		tx_buffer->next_to_watch = NULL;
+
+		/* update the statistics for this packet */
+		total_bytes += tx_buffer->bytecount;
+		total_packets += tx_buffer->gso_segs;
+
+		/* free the skb */
+		dev_consume_skb_any(tx_buffer->skb);
+
+		/* unmap skb header data */
+		dma_unmap_single(tx_ring->dev,
+				 dma_unmap_addr(tx_buffer, dma),
+				 dma_unmap_len(tx_buffer, len),
+				 DMA_TO_DEVICE);
+
+		/* clear tx_buffer data */
+		tx_buffer->skb = NULL;
+		dma_unmap_len_set(tx_buffer, len, 0);
+
+		/* unmap remaining buffers */
+		while (tx_desc != eop_desc) {
+			tx_buffer++;
+			tx_desc++;
+			i++;
+			if (unlikely(!i)) {
+				i -= tx_ring->count;
+				tx_buffer = tx_ring->tx_buffer;
+				tx_desc = FM10K_TX_DESC(tx_ring, 0);
+			}
+
+			/* unmap any remaining paged data */
+			if (dma_unmap_len(tx_buffer, len)) {
+				dma_unmap_page(tx_ring->dev,
+					       dma_unmap_addr(tx_buffer, dma),
+					       dma_unmap_len(tx_buffer, len),
+					       DMA_TO_DEVICE);
+				dma_unmap_len_set(tx_buffer, len, 0);
+			}
+		}
+
+		/* move us one more past the eop_desc for start of next pkt */
+		tx_buffer++;
+		tx_desc++;
+		i++;
+		if (unlikely(!i)) {
+			i -= tx_ring->count;
+			tx_buffer = tx_ring->tx_buffer;
+			tx_desc = FM10K_TX_DESC(tx_ring, 0);
+		}
+
+		/* issue prefetch for next Tx descriptor */
+		prefetch(tx_desc);
+
+		/* update budget accounting */
+		budget--;
+	} while (likely(budget));
+
+	i += tx_ring->count;
+	tx_ring->next_to_clean = i;
+	u64_stats_update_begin(&tx_ring->syncp);
+	tx_ring->stats.bytes += total_bytes;
+	tx_ring->stats.packets += total_packets;
+	u64_stats_update_end(&tx_ring->syncp);
+	q_vector->tx.total_bytes += total_bytes;
+	q_vector->tx.total_packets += total_packets;
+
+	if (check_for_tx_hang(tx_ring) && fm10k_check_tx_hang(tx_ring)) {
+		/* schedule immediate reset if we believe we hung */
+		struct fm10k_hw *hw = &interface->hw;
+
+		netif_err(interface, drv, tx_ring->netdev,
+			  "Detected Tx Unit Hang\n"
+			  "  Tx Queue             <%d>\n"
+			  "  TDH, TDT             <%x>, <%x>\n"
+			  "  next_to_use          <%x>\n"
+			  "  next_to_clean        <%x>\n",
+			  tx_ring->queue_index,
+			  fm10k_read_reg(hw, FM10K_TDH(tx_ring->reg_idx)),
+			  fm10k_read_reg(hw, FM10K_TDT(tx_ring->reg_idx)),
+			  tx_ring->next_to_use, i);
+
+		netif_stop_subqueue(tx_ring->netdev,
+				    tx_ring->queue_index);
+
+		netif_info(interface, probe, tx_ring->netdev,
+			   "tx hang %d detected on queue %d, resetting interface\n",
+			   interface->tx_timeout_count + 1,
+			   tx_ring->queue_index);
+
+		fm10k_tx_timeout_reset(interface);
+
+		/* the netdev is about to reset, no point in enabling stuff */
+		return true;
+	}
+
+	/* notify netdev of completed buffers */
+	netdev_tx_completed_queue(txring_txq(tx_ring),
+				  total_packets, total_bytes);
+
+#define TX_WAKE_THRESHOLD min_t(u16, FM10K_MIN_TXD - 1, DESC_NEEDED * 2)
+	if (unlikely(total_packets && netif_carrier_ok(tx_ring->netdev) &&
+		     (fm10k_desc_unused(tx_ring) >= TX_WAKE_THRESHOLD))) {
+		/* Make sure that anybody stopping the queue after this
+		 * sees the new next_to_clean.
+		 */
+		smp_mb();
+		if (__netif_subqueue_stopped(tx_ring->netdev,
+					     tx_ring->queue_index) &&
+		    !test_bit(__FM10K_DOWN, &interface->state)) {
+			netif_wake_subqueue(tx_ring->netdev,
+					    tx_ring->queue_index);
+			++tx_ring->tx_stats.restart_queue;
+		}
+	}
+
+	return !!budget;
+}
+
 /**
  * fm10k_update_itr - update the dynamic ITR value based on packet size
  *
@@ -137,6 +1053,28 @@ static int fm10k_poll(struct napi_struct *napi, int budget)
 {
 	struct fm10k_q_vector *q_vector =
 			       container_of(napi, struct fm10k_q_vector, napi);
+	struct fm10k_ring *ring;
+	int per_ring_budget;
+	bool clean_complete = true;
+
+	fm10k_for_each_ring(ring, q_vector->tx)
+		clean_complete &= fm10k_clean_tx_irq(q_vector, ring);
+
+	/* attempt to distribute budget to each queue fairly, but don't
+	 * allow the budget to go below 1 because we'll exit polling
+	 */
+	if (q_vector->rx.count > 1)
+		per_ring_budget = max(budget/q_vector->rx.count, 1);
+	else
+		per_ring_budget = budget;
+
+	fm10k_for_each_ring(ring, q_vector->rx)
+		clean_complete &= fm10k_clean_rx_irq(q_vector, ring,
+						     per_ring_budget);
+
+	/* If all work not completed, return budget and keep polling */
+	if (!clean_complete)
+		return budget;
 
 	/* all work done, exit the polling mode */
 	napi_complete(napi);