--- /dev/null
+/*******************************************************************************
+ *
+ * Intel Ethernet Controller XL710 Family Linux Virtual Function Driver
+ * Copyright(c) 2013 - 2014 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * The full GNU General Public License is included in this distribution in
+ * the file called "COPYING".
+ *
+ * Contact Information:
+ * e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
+ * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
+ *
+ ******************************************************************************/
+
+#include <linux/prefetch.h>
+#include <net/busy_poll.h>
+
+#include "i40evf.h"
+#include "i40e_prototype.h"
+
+static inline __le64 build_ctob(u32 td_cmd, u32 td_offset, unsigned int size,
+ u32 td_tag)
+{
+ return cpu_to_le64(I40E_TX_DESC_DTYPE_DATA |
+ ((u64)td_cmd << I40E_TXD_QW1_CMD_SHIFT) |
+ ((u64)td_offset << I40E_TXD_QW1_OFFSET_SHIFT) |
+ ((u64)size << I40E_TXD_QW1_TX_BUF_SZ_SHIFT) |
+ ((u64)td_tag << I40E_TXD_QW1_L2TAG1_SHIFT));
+}
+
+#define I40E_TXD_CMD (I40E_TX_DESC_CMD_EOP | I40E_TX_DESC_CMD_RS)
+
+/**
+ * i40e_unmap_and_free_tx_resource - Release a Tx buffer
+ * @ring: the ring that owns the buffer
+ * @tx_buffer: the buffer to free
+ **/
+static void i40e_unmap_and_free_tx_resource(struct i40e_ring *ring,
+ struct i40e_tx_buffer *tx_buffer)
+{
+ if (tx_buffer->skb) {
+ if (tx_buffer->tx_flags & I40E_TX_FLAGS_FD_SB)
+ kfree(tx_buffer->raw_buf);
+ else
+ dev_kfree_skb_any(tx_buffer->skb);
+
+ if (dma_unmap_len(tx_buffer, len))
+ dma_unmap_single(ring->dev,
+ dma_unmap_addr(tx_buffer, dma),
+ dma_unmap_len(tx_buffer, len),
+ DMA_TO_DEVICE);
+ } else if (dma_unmap_len(tx_buffer, len)) {
+ dma_unmap_page(ring->dev,
+ dma_unmap_addr(tx_buffer, dma),
+ dma_unmap_len(tx_buffer, len),
+ DMA_TO_DEVICE);
+ }
+ tx_buffer->next_to_watch = NULL;
+ tx_buffer->skb = NULL;
+ dma_unmap_len_set(tx_buffer, len, 0);
+ /* tx_buffer must be completely set up in the transmit path */
+}
+
+/**
+ * i40evf_clean_tx_ring - Free any empty Tx buffers
+ * @tx_ring: ring to be cleaned
+ **/
+void i40evf_clean_tx_ring(struct i40e_ring *tx_ring)
+{
+ unsigned long bi_size;
+ u16 i;
+
+ /* ring already cleared, nothing to do */
+ if (!tx_ring->tx_bi)
+ return;
+
+ /* Free all the Tx ring sk_buffs */
+ for (i = 0; i < tx_ring->count; i++)
+ i40e_unmap_and_free_tx_resource(tx_ring, &tx_ring->tx_bi[i]);
+
+ bi_size = sizeof(struct i40e_tx_buffer) * tx_ring->count;
+ memset(tx_ring->tx_bi, 0, bi_size);
+
+ /* Zero out the descriptor ring */
+ memset(tx_ring->desc, 0, tx_ring->size);
+
+ tx_ring->next_to_use = 0;
+ tx_ring->next_to_clean = 0;
+
+ if (!tx_ring->netdev)
+ return;
+
+ /* cleanup Tx queue statistics */
+ netdev_tx_reset_queue(netdev_get_tx_queue(tx_ring->netdev,
+ tx_ring->queue_index));
+}
+
+/**
+ * i40evf_free_tx_resources - Free Tx resources per queue
+ * @tx_ring: Tx descriptor ring for a specific queue
+ *
+ * Free all transmit software resources
+ **/
+void i40evf_free_tx_resources(struct i40e_ring *tx_ring)
+{
+ i40evf_clean_tx_ring(tx_ring);
+ kfree(tx_ring->tx_bi);
+ tx_ring->tx_bi = NULL;
+
+ if (tx_ring->desc) {
+ dma_free_coherent(tx_ring->dev, tx_ring->size,
+ tx_ring->desc, tx_ring->dma);
+ tx_ring->desc = NULL;
+ }
+}
+
+/**
+ * i40e_get_head - Retrieve head from head writeback
+ * @tx_ring: tx ring to fetch head of
+ *
+ * Returns value of Tx ring head based on value stored
+ * in head write-back location
+ **/
+static inline u32 i40e_get_head(struct i40e_ring *tx_ring)
+{
+ void *head = (struct i40e_tx_desc *)tx_ring->desc + tx_ring->count;
+
+ return le32_to_cpu(*(volatile __le32 *)head);
+}
+
+/**
+ * i40e_get_tx_pending - how many tx descriptors not processed
+ * @tx_ring: the ring of descriptors
+ *
+ * Since there is no access to the ring head register
+ * in XL710, we need to use our local copies
+ **/
+static u32 i40e_get_tx_pending(struct i40e_ring *ring)
+{
+ u32 head, tail;
+
+ head = i40e_get_head(ring);
+ tail = readl(ring->tail);
+
+ if (head != tail)
+ return (head < tail) ?
+ tail - head : (tail + ring->count - head);
+
+ return 0;
+}
+
+/**
+ * i40e_check_tx_hang - Is there a hang in the Tx queue
+ * @tx_ring: the ring of descriptors
+ **/
+static bool i40e_check_tx_hang(struct i40e_ring *tx_ring)
+{
+ u32 tx_done = tx_ring->stats.packets;
+ u32 tx_done_old = tx_ring->tx_stats.tx_done_old;
+ u32 tx_pending = i40e_get_tx_pending(tx_ring);
+ bool ret = false;
+
+ 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. The
+ * ARMED bit is set to indicate a potential hang. The
+ * bit is cleared if a pause frame is received to remove
+ * false hang detection due to PFC or 802.3x frames. By
+ * requiring this to fail twice we avoid races with
+ * PFC 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_done_old == tx_done) && tx_pending) {
+ /* make sure it is true for two checks in a row */
+ ret = test_and_set_bit(__I40E_HANG_CHECK_ARMED,
+ &tx_ring->state);
+ } else if (tx_done_old == tx_done &&
+ (tx_pending < I40E_MIN_DESC_PENDING) && (tx_pending > 0)) {
+ /* update completed stats and disarm the hang check */
+ tx_ring->tx_stats.tx_done_old = tx_done;
+ clear_bit(__I40E_HANG_CHECK_ARMED, &tx_ring->state);
+ }
+
+ return ret;
+}
+
+#define WB_STRIDE 0x3
+
+/**
+ * i40e_clean_tx_irq - Reclaim resources after transmit completes
+ * @tx_ring: tx ring to clean
+ * @budget: how many cleans we're allowed
+ *
+ * Returns true if there's any budget left (e.g. the clean is finished)
+ **/
+static bool i40e_clean_tx_irq(struct i40e_ring *tx_ring, int budget)
+{
+ u16 i = tx_ring->next_to_clean;
+ struct i40e_tx_buffer *tx_buf;
+ struct i40e_tx_desc *tx_head;
+ struct i40e_tx_desc *tx_desc;
+ unsigned int total_packets = 0;
+ unsigned int total_bytes = 0;
+
+ tx_buf = &tx_ring->tx_bi[i];
+ tx_desc = I40E_TX_DESC(tx_ring, i);
+ i -= tx_ring->count;
+
+ tx_head = I40E_TX_DESC(tx_ring, i40e_get_head(tx_ring));
+
+ do {
+ struct i40e_tx_desc *eop_desc = tx_buf->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();
+
+ /* we have caught up to head, no work left to do */
+ if (tx_head == tx_desc)
+ break;
+
+ /* clear next_to_watch to prevent false hangs */
+ tx_buf->next_to_watch = NULL;
+
+ /* update the statistics for this packet */
+ total_bytes += tx_buf->bytecount;
+ total_packets += tx_buf->gso_segs;
+
+ /* free the skb */
+ dev_kfree_skb_any(tx_buf->skb);
+
+ /* unmap skb header data */
+ dma_unmap_single(tx_ring->dev,
+ dma_unmap_addr(tx_buf, dma),
+ dma_unmap_len(tx_buf, len),
+ DMA_TO_DEVICE);
+
+ /* clear tx_buffer data */
+ tx_buf->skb = NULL;
+ dma_unmap_len_set(tx_buf, len, 0);
+
+ /* unmap remaining buffers */
+ while (tx_desc != eop_desc) {
+
+ tx_buf++;
+ tx_desc++;
+ i++;
+ if (unlikely(!i)) {
+ i -= tx_ring->count;
+ tx_buf = tx_ring->tx_bi;
+ tx_desc = I40E_TX_DESC(tx_ring, 0);
+ }
+
+ /* unmap any remaining paged data */
+ if (dma_unmap_len(tx_buf, len)) {
+ dma_unmap_page(tx_ring->dev,
+ dma_unmap_addr(tx_buf, dma),
+ dma_unmap_len(tx_buf, len),
+ DMA_TO_DEVICE);
+ dma_unmap_len_set(tx_buf, len, 0);
+ }
+ }
+
+ /* move us one more past the eop_desc for start of next pkt */
+ tx_buf++;
+ tx_desc++;
+ i++;
+ if (unlikely(!i)) {
+ i -= tx_ring->count;
+ tx_buf = tx_ring->tx_bi;
+ tx_desc = I40E_TX_DESC(tx_ring, 0);
+ }
+
+ 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);
+ tx_ring->q_vector->tx.total_bytes += total_bytes;
+ tx_ring->q_vector->tx.total_packets += total_packets;
+
+ if (budget &&
+ !((i & WB_STRIDE) == WB_STRIDE) &&
+ !test_bit(__I40E_DOWN, &tx_ring->vsi->state) &&
+ (I40E_DESC_UNUSED(tx_ring) != tx_ring->count))
+ tx_ring->arm_wb = true;
+ else
+ tx_ring->arm_wb = false;
+
+ if (check_for_tx_hang(tx_ring) && i40e_check_tx_hang(tx_ring)) {
+ /* schedule immediate reset if we believe we hung */
+ dev_info(tx_ring->dev, "Detected Tx Unit Hang\n"
+ " VSI <%d>\n"
+ " Tx Queue <%d>\n"
+ " next_to_use <%x>\n"
+ " next_to_clean <%x>\n",
+ tx_ring->vsi->seid,
+ tx_ring->queue_index,
+ tx_ring->next_to_use, i);
+ dev_info(tx_ring->dev, "tx_bi[next_to_clean]\n"
+ " time_stamp <%lx>\n"
+ " jiffies <%lx>\n",
+ tx_ring->tx_bi[i].time_stamp, jiffies);
+
+ netif_stop_subqueue(tx_ring->netdev, tx_ring->queue_index);
+
+ dev_info(tx_ring->dev,
+ "tx hang detected on queue %d, resetting adapter\n",
+ tx_ring->queue_index);
+
+ tx_ring->netdev->netdev_ops->ndo_tx_timeout(tx_ring->netdev);
+
+ /* the adapter is about to reset, no point in enabling stuff */
+ return true;
+ }
+
+ netdev_tx_completed_queue(netdev_get_tx_queue(tx_ring->netdev,
+ tx_ring->queue_index),
+ total_packets, total_bytes);
+
+#define TX_WAKE_THRESHOLD (DESC_NEEDED * 2)
+ if (unlikely(total_packets && netif_carrier_ok(tx_ring->netdev) &&
+ (I40E_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(__I40E_DOWN, &tx_ring->vsi->state)) {
+ netif_wake_subqueue(tx_ring->netdev,
+ tx_ring->queue_index);
+ ++tx_ring->tx_stats.restart_queue;
+ }
+ }
+
+ return budget > 0;
+}
+
+/**
+ * i40e_force_wb -Arm hardware to do a wb on noncache aligned descriptors
+ * @vsi: the VSI we care about
+ * @q_vector: the vector on which to force writeback
+ *
+ **/
+static void i40e_force_wb(struct i40e_vsi *vsi, struct i40e_q_vector *q_vector)
+{
+ u32 val = I40E_VFINT_DYN_CTLN_INTENA_MASK |
+ I40E_VFINT_DYN_CTLN1_ITR_INDX_MASK | /* set noitr */
+ I40E_VFINT_DYN_CTLN_SWINT_TRIG_MASK |
+ I40E_VFINT_DYN_CTLN_SW_ITR_INDX_ENA_MASK;
+ /* allow 00 to be written to the index */
+
+ wr32(&vsi->back->hw,
+ I40E_VFINT_DYN_CTLN1(q_vector->v_idx + vsi->base_vector - 1),
+ val);
+}
+
+/**
+ * i40e_set_new_dynamic_itr - Find new ITR level
+ * @rc: structure containing ring performance data
+ *
+ * Stores a new ITR value based on packets and byte counts during
+ * the last interrupt. The advantage of per interrupt computation
+ * is faster updates and more accurate ITR for the current traffic
+ * pattern. Constants in this function were computed based on
+ * theoretical maximum wire speed and thresholds were set based on
+ * testing data as well as attempting to minimize response time
+ * while increasing bulk throughput.
+ **/
+static void i40e_set_new_dynamic_itr(struct i40e_ring_container *rc)
+{
+ enum i40e_latency_range new_latency_range = rc->latency_range;
+ u32 new_itr = rc->itr;
+ int bytes_per_int;
+
+ if (rc->total_packets == 0 || !rc->itr)
+ return;
+
+ /* simple throttlerate management
+ * 0-10MB/s lowest (100000 ints/s)
+ * 10-20MB/s low (20000 ints/s)
+ * 20-1249MB/s bulk (8000 ints/s)
+ */
+ bytes_per_int = rc->total_bytes / rc->itr;
+ switch (rc->itr) {
+ case I40E_LOWEST_LATENCY:
+ if (bytes_per_int > 10)
+ new_latency_range = I40E_LOW_LATENCY;
+ break;
+ case I40E_LOW_LATENCY:
+ if (bytes_per_int > 20)
+ new_latency_range = I40E_BULK_LATENCY;
+ else if (bytes_per_int <= 10)
+ new_latency_range = I40E_LOWEST_LATENCY;
+ break;
+ case I40E_BULK_LATENCY:
+ if (bytes_per_int <= 20)
+ rc->latency_range = I40E_LOW_LATENCY;
+ break;
+ }
+
+ switch (new_latency_range) {
+ case I40E_LOWEST_LATENCY:
+ new_itr = I40E_ITR_100K;
+ break;
+ case I40E_LOW_LATENCY:
+ new_itr = I40E_ITR_20K;
+ break;
+ case I40E_BULK_LATENCY:
+ new_itr = I40E_ITR_8K;
+ break;
+ default:
+ break;
+ }
+
+ if (new_itr != rc->itr) {
+ /* do an exponential smoothing */
+ new_itr = (10 * new_itr * rc->itr) /
+ ((9 * new_itr) + rc->itr);
+ rc->itr = new_itr & I40E_MAX_ITR;
+ }
+
+ rc->total_bytes = 0;
+ rc->total_packets = 0;
+}
+
+/**
+ * i40e_update_dynamic_itr - Adjust ITR based on bytes per int
+ * @q_vector: the vector to adjust
+ **/
+static void i40e_update_dynamic_itr(struct i40e_q_vector *q_vector)
+{
+ u16 vector = q_vector->vsi->base_vector + q_vector->v_idx;
+ struct i40e_hw *hw = &q_vector->vsi->back->hw;
+ u32 reg_addr;
+ u16 old_itr;
+
+ reg_addr = I40E_VFINT_ITRN1(I40E_RX_ITR, vector - 1);
+ old_itr = q_vector->rx.itr;
+ i40e_set_new_dynamic_itr(&q_vector->rx);
+ if (old_itr != q_vector->rx.itr)
+ wr32(hw, reg_addr, q_vector->rx.itr);
+
+ reg_addr = I40E_VFINT_ITRN1(I40E_TX_ITR, vector - 1);
+ old_itr = q_vector->tx.itr;
+ i40e_set_new_dynamic_itr(&q_vector->tx);
+ if (old_itr != q_vector->tx.itr)
+ wr32(hw, reg_addr, q_vector->tx.itr);
+}
+
+/**
+ * i40evf_setup_tx_descriptors - Allocate the Tx descriptors
+ * @tx_ring: the tx ring to set up
+ *
+ * Return 0 on success, negative on error
+ **/
+int i40evf_setup_tx_descriptors(struct i40e_ring *tx_ring)
+{
+ struct device *dev = tx_ring->dev;
+ int bi_size;
+
+ if (!dev)
+ return -ENOMEM;
+
+ bi_size = sizeof(struct i40e_tx_buffer) * tx_ring->count;
+ tx_ring->tx_bi = kzalloc(bi_size, GFP_KERNEL);
+ if (!tx_ring->tx_bi)
+ goto err;
+
+ /* round up to nearest 4K */
+ tx_ring->size = tx_ring->count * sizeof(struct i40e_tx_desc);
+ /* add u32 for head writeback, align after this takes care of
+ * guaranteeing this is at least one cache line in size
+ */
+ tx_ring->size += sizeof(u32);
+ tx_ring->size = ALIGN(tx_ring->size, 4096);
+ tx_ring->desc = dma_alloc_coherent(dev, tx_ring->size,
+ &tx_ring->dma, GFP_KERNEL);
+ if (!tx_ring->desc) {
+ dev_info(dev, "Unable to allocate memory for the Tx descriptor ring, size=%d\n",
+ tx_ring->size);
+ goto err;
+ }
+
+ tx_ring->next_to_use = 0;
+ tx_ring->next_to_clean = 0;
+ return 0;
+
+err:
+ kfree(tx_ring->tx_bi);
+ tx_ring->tx_bi = NULL;
+ return -ENOMEM;
+}
+
+/**
+ * i40evf_clean_rx_ring - Free Rx buffers
+ * @rx_ring: ring to be cleaned
+ **/
+void i40evf_clean_rx_ring(struct i40e_ring *rx_ring)
+{
+ struct device *dev = rx_ring->dev;
+ struct i40e_rx_buffer *rx_bi;
+ unsigned long bi_size;
+ u16 i;
+
+ /* ring already cleared, nothing to do */
+ if (!rx_ring->rx_bi)
+ return;
+
+ if (ring_is_ps_enabled(rx_ring)) {
+ int bufsz = ALIGN(rx_ring->rx_hdr_len, 256) * rx_ring->count;
+
+ rx_bi = &rx_ring->rx_bi[0];
+ if (rx_bi->hdr_buf) {
+ dma_free_coherent(dev,
+ bufsz,
+ rx_bi->hdr_buf,
+ rx_bi->dma);
+ for (i = 0; i < rx_ring->count; i++) {
+ rx_bi = &rx_ring->rx_bi[i];
+ rx_bi->dma = 0;
+ rx_bi->hdr_buf = NULL;
+ }
+ }
+ }
+ /* Free all the Rx ring sk_buffs */
+ for (i = 0; i < rx_ring->count; i++) {
+ rx_bi = &rx_ring->rx_bi[i];
+ if (rx_bi->dma) {
+ dma_unmap_single(dev,
+ rx_bi->dma,
+ rx_ring->rx_buf_len,
+ DMA_FROM_DEVICE);
+ rx_bi->dma = 0;
+ }
+ if (rx_bi->skb) {
+ dev_kfree_skb(rx_bi->skb);
+ rx_bi->skb = NULL;
+ }
+ if (rx_bi->page) {
+ if (rx_bi->page_dma) {
+ dma_unmap_page(dev,
+ rx_bi->page_dma,
+ PAGE_SIZE / 2,
+ DMA_FROM_DEVICE);
+ rx_bi->page_dma = 0;
+ }
+ __free_page(rx_bi->page);
+ rx_bi->page = NULL;
+ rx_bi->page_offset = 0;
+ }
+ }
+
+ bi_size = sizeof(struct i40e_rx_buffer) * rx_ring->count;
+ memset(rx_ring->rx_bi, 0, bi_size);
+
+ /* Zero out the descriptor ring */
+ memset(rx_ring->desc, 0, rx_ring->size);
+
+ rx_ring->next_to_clean = 0;
+ rx_ring->next_to_use = 0;
+}
+
+/**
+ * i40evf_free_rx_resources - Free Rx resources
+ * @rx_ring: ring to clean the resources from
+ *
+ * Free all receive software resources
+ **/
+void i40evf_free_rx_resources(struct i40e_ring *rx_ring)
+{
+ i40evf_clean_rx_ring(rx_ring);
+ kfree(rx_ring->rx_bi);
+ rx_ring->rx_bi = NULL;
+
+ if (rx_ring->desc) {
+ dma_free_coherent(rx_ring->dev, rx_ring->size,
+ rx_ring->desc, rx_ring->dma);
+ rx_ring->desc = NULL;
+ }
+}
+
+/**
+ * i40evf_alloc_rx_headers - allocate rx header buffers
+ * @rx_ring: ring to alloc buffers
+ *
+ * Allocate rx header buffers for the entire ring. As these are static,
+ * this is only called when setting up a new ring.
+ **/
+void i40evf_alloc_rx_headers(struct i40e_ring *rx_ring)
+{
+ struct device *dev = rx_ring->dev;
+ struct i40e_rx_buffer *rx_bi;
+ dma_addr_t dma;
+ void *buffer;
+ int buf_size;
+ int i;
+
+ if (rx_ring->rx_bi[0].hdr_buf)
+ return;
+ /* Make sure the buffers don't cross cache line boundaries. */
+ buf_size = ALIGN(rx_ring->rx_hdr_len, 256);
+ buffer = dma_alloc_coherent(dev, buf_size * rx_ring->count,
+ &dma, GFP_KERNEL);
+ if (!buffer)
+ return;
+ for (i = 0; i < rx_ring->count; i++) {
+ rx_bi = &rx_ring->rx_bi[i];
+ rx_bi->dma = dma + (i * buf_size);
+ rx_bi->hdr_buf = buffer + (i * buf_size);
+ }
+}
+
+/**
+ * i40evf_setup_rx_descriptors - Allocate Rx descriptors
+ * @rx_ring: Rx descriptor ring (for a specific queue) to setup
+ *
+ * Returns 0 on success, negative on failure
+ **/
+int i40evf_setup_rx_descriptors(struct i40e_ring *rx_ring)
+{
+ struct device *dev = rx_ring->dev;
+ int bi_size;
+
+ bi_size = sizeof(struct i40e_rx_buffer) * rx_ring->count;
+ rx_ring->rx_bi = kzalloc(bi_size, GFP_KERNEL);
+ if (!rx_ring->rx_bi)
+ goto err;
+
+ u64_stats_init(&rx_ring->syncp);
+
+ /* Round up to nearest 4K */
+ rx_ring->size = ring_is_16byte_desc_enabled(rx_ring)
+ ? rx_ring->count * sizeof(union i40e_16byte_rx_desc)
+ : rx_ring->count * sizeof(union i40e_32byte_rx_desc);
+ rx_ring->size = ALIGN(rx_ring->size, 4096);
+ rx_ring->desc = dma_alloc_coherent(dev, rx_ring->size,
+ &rx_ring->dma, GFP_KERNEL);
+
+ if (!rx_ring->desc) {
+ dev_info(dev, "Unable to allocate memory for the Rx descriptor ring, size=%d\n",
+ rx_ring->size);
+ goto err;
+ }
+
+ rx_ring->next_to_clean = 0;
+ rx_ring->next_to_use = 0;
+
+ return 0;
+err:
+ kfree(rx_ring->rx_bi);
+ rx_ring->rx_bi = NULL;
+ return -ENOMEM;
+}
+
+/**
+ * i40e_release_rx_desc - Store the new tail and head values
+ * @rx_ring: ring to bump
+ * @val: new head index
+ **/
+static inline void i40e_release_rx_desc(struct i40e_ring *rx_ring, u32 val)
+{
+ rx_ring->next_to_use = val;
+ /* 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();
+ writel(val, rx_ring->tail);
+}
+
+/**
+ * i40evf_alloc_rx_buffers_ps - Replace used receive buffers; packet split
+ * @rx_ring: ring to place buffers on
+ * @cleaned_count: number of buffers to replace
+ **/
+void i40evf_alloc_rx_buffers_ps(struct i40e_ring *rx_ring, u16 cleaned_count)
+{
+ u16 i = rx_ring->next_to_use;
+ union i40e_rx_desc *rx_desc;
+ struct i40e_rx_buffer *bi;
+
+ /* do nothing if no valid netdev defined */
+ if (!rx_ring->netdev || !cleaned_count)
+ return;
+
+ while (cleaned_count--) {
+ rx_desc = I40E_RX_DESC(rx_ring, i);
+ bi = &rx_ring->rx_bi[i];
+
+ if (bi->skb) /* desc is in use */
+ goto no_buffers;
+ if (!bi->page) {
+ bi->page = alloc_page(GFP_ATOMIC);
+ if (!bi->page) {
+ rx_ring->rx_stats.alloc_page_failed++;
+ goto no_buffers;
+ }
+ }
+
+ if (!bi->page_dma) {
+ /* use a half page if we're re-using */
+ bi->page_offset ^= PAGE_SIZE / 2;
+ bi->page_dma = dma_map_page(rx_ring->dev,
+ bi->page,
+ bi->page_offset,
+ PAGE_SIZE / 2,
+ DMA_FROM_DEVICE);
+ if (dma_mapping_error(rx_ring->dev,
+ bi->page_dma)) {
+ rx_ring->rx_stats.alloc_page_failed++;
+ bi->page_dma = 0;
+ goto no_buffers;
+ }
+ }
+
+ dma_sync_single_range_for_device(rx_ring->dev,
+ bi->dma,
+ 0,
+ rx_ring->rx_hdr_len,
+ DMA_FROM_DEVICE);
+ /* Refresh the desc even if buffer_addrs didn't change
+ * because each write-back erases this info.
+ */
+ rx_desc->read.pkt_addr = cpu_to_le64(bi->page_dma);
+ rx_desc->read.hdr_addr = cpu_to_le64(bi->dma);
+ i++;
+ if (i == rx_ring->count)
+ i = 0;
+ }
+
+no_buffers:
+ if (rx_ring->next_to_use != i)
+ i40e_release_rx_desc(rx_ring, i);
+}
+
+/**
+ * i40evf_alloc_rx_buffers_1buf - Replace used receive buffers; single buffer
+ * @rx_ring: ring to place buffers on
+ * @cleaned_count: number of buffers to replace
+ **/
+void i40evf_alloc_rx_buffers_1buf(struct i40e_ring *rx_ring, u16 cleaned_count)
+{
+ u16 i = rx_ring->next_to_use;
+ union i40e_rx_desc *rx_desc;
+ struct i40e_rx_buffer *bi;
+ struct sk_buff *skb;
+
+ /* do nothing if no valid netdev defined */
+ if (!rx_ring->netdev || !cleaned_count)
+ return;
+
+ while (cleaned_count--) {
+ rx_desc = I40E_RX_DESC(rx_ring, i);
+ bi = &rx_ring->rx_bi[i];
+ skb = bi->skb;
+
+ if (!skb) {
+ skb = netdev_alloc_skb_ip_align(rx_ring->netdev,
+ rx_ring->rx_buf_len);
+ if (!skb) {
+ rx_ring->rx_stats.alloc_buff_failed++;
+ goto no_buffers;
+ }
+ /* initialize queue mapping */
+ skb_record_rx_queue(skb, rx_ring->queue_index);
+ bi->skb = skb;
+ }
+
+ if (!bi->dma) {
+ bi->dma = dma_map_single(rx_ring->dev,
+ skb->data,
+ rx_ring->rx_buf_len,
+ DMA_FROM_DEVICE);
+ if (dma_mapping_error(rx_ring->dev, bi->dma)) {
+ rx_ring->rx_stats.alloc_buff_failed++;
+ bi->dma = 0;
+ goto no_buffers;
+ }
+ }
+
+ rx_desc->read.pkt_addr = cpu_to_le64(bi->dma);
+ rx_desc->read.hdr_addr = 0;
+ i++;
+ if (i == rx_ring->count)
+ i = 0;
+ }
+
+no_buffers:
+ if (rx_ring->next_to_use != i)
+ i40e_release_rx_desc(rx_ring, i);
+}
+
+/**
+ * i40e_receive_skb - Send a completed packet up the stack
+ * @rx_ring: rx ring in play
+ * @skb: packet to send up
+ * @vlan_tag: vlan tag for packet
+ **/
+static void i40e_receive_skb(struct i40e_ring *rx_ring,
+ struct sk_buff *skb, u16 vlan_tag)
+{
+ struct i40e_q_vector *q_vector = rx_ring->q_vector;
+ struct i40e_vsi *vsi = rx_ring->vsi;
+ u64 flags = vsi->back->flags;
+
+ if (vlan_tag & VLAN_VID_MASK)
+ __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), vlan_tag);
+
+ if (flags & I40E_FLAG_IN_NETPOLL)
+ netif_rx(skb);
+ else
+ napi_gro_receive(&q_vector->napi, skb);
+}
+
+/**
+ * i40e_rx_checksum - Indicate in skb if hw indicated a good cksum
+ * @vsi: the VSI we care about
+ * @skb: skb currently being received and modified
+ * @rx_status: status value of last descriptor in packet
+ * @rx_error: error value of last descriptor in packet
+ * @rx_ptype: ptype value of last descriptor in packet
+ **/
+static inline void i40e_rx_checksum(struct i40e_vsi *vsi,
+ struct sk_buff *skb,
+ u32 rx_status,
+ u32 rx_error,
+ u16 rx_ptype)
+{
+ struct i40e_rx_ptype_decoded decoded = decode_rx_desc_ptype(rx_ptype);
+ bool ipv4 = false, ipv6 = false;
+ bool ipv4_tunnel, ipv6_tunnel;
+ __wsum rx_udp_csum;
+ struct iphdr *iph;
+ __sum16 csum;
+
+ ipv4_tunnel = (rx_ptype >= I40E_RX_PTYPE_GRENAT4_MAC_PAY3) &&
+ (rx_ptype <= I40E_RX_PTYPE_GRENAT4_MACVLAN_IPV6_ICMP_PAY4);
+ ipv6_tunnel = (rx_ptype >= I40E_RX_PTYPE_GRENAT6_MAC_PAY3) &&
+ (rx_ptype <= I40E_RX_PTYPE_GRENAT6_MACVLAN_IPV6_ICMP_PAY4);
+
+ skb->ip_summed = CHECKSUM_NONE;
+
+ /* Rx csum enabled and ip headers found? */
+ if (!(vsi->netdev->features & NETIF_F_RXCSUM))
+ return;
+
+ /* did the hardware decode the packet and checksum? */
+ if (!(rx_status & (1 << I40E_RX_DESC_STATUS_L3L4P_SHIFT)))
+ return;
+
+ /* both known and outer_ip must be set for the below code to work */
+ if (!(decoded.known && decoded.outer_ip))
+ return;
+
+ if (decoded.outer_ip == I40E_RX_PTYPE_OUTER_IP &&
+ decoded.outer_ip_ver == I40E_RX_PTYPE_OUTER_IPV4)
+ ipv4 = true;
+ else if (decoded.outer_ip == I40E_RX_PTYPE_OUTER_IP &&
+ decoded.outer_ip_ver == I40E_RX_PTYPE_OUTER_IPV6)
+ ipv6 = true;
+
+ if (ipv4 &&
+ (rx_error & ((1 << I40E_RX_DESC_ERROR_IPE_SHIFT) |
+ (1 << I40E_RX_DESC_ERROR_EIPE_SHIFT))))
+ goto checksum_fail;
+
+ /* likely incorrect csum if alternate IP extension headers found */
+ if (ipv6 &&
+ rx_status & (1 << I40E_RX_DESC_STATUS_IPV6EXADD_SHIFT))
+ /* don't increment checksum err here, non-fatal err */
+ return;
+
+ /* there was some L4 error, count error and punt packet to the stack */
+ if (rx_error & (1 << I40E_RX_DESC_ERROR_L4E_SHIFT))
+ goto checksum_fail;
+
+ /* handle packets that were not able to be checksummed due
+ * to arrival speed, in this case the stack can compute
+ * the csum.
+ */
+ if (rx_error & (1 << I40E_RX_DESC_ERROR_PPRS_SHIFT))
+ return;
+
+ /* If VXLAN traffic has an outer UDPv4 checksum we need to check
+ * it in the driver, hardware does not do it for us.
+ * Since L3L4P bit was set we assume a valid IHL value (>=5)
+ * so the total length of IPv4 header is IHL*4 bytes
+ * The UDP_0 bit *may* bet set if the *inner* header is UDP
+ */
+ if (ipv4_tunnel) {
+ skb->transport_header = skb->mac_header +
+ sizeof(struct ethhdr) +
+ (ip_hdr(skb)->ihl * 4);
+
+ /* Add 4 bytes for VLAN tagged packets */
+ skb->transport_header += (skb->protocol == htons(ETH_P_8021Q) ||
+ skb->protocol == htons(ETH_P_8021AD))
+ ? VLAN_HLEN : 0;
+
+ if ((ip_hdr(skb)->protocol == IPPROTO_UDP) &&
+ (udp_hdr(skb)->check != 0)) {
+ rx_udp_csum = udp_csum(skb);
+ iph = ip_hdr(skb);
+ csum = csum_tcpudp_magic(iph->saddr, iph->daddr,
+ (skb->len -
+ skb_transport_offset(skb)),
+ IPPROTO_UDP, rx_udp_csum);
+
+ if (udp_hdr(skb)->check != csum)
+ goto checksum_fail;
+
+ } /* else its GRE and so no outer UDP header */
+ }
+
+ skb->ip_summed = CHECKSUM_UNNECESSARY;
+ skb->csum_level = ipv4_tunnel || ipv6_tunnel;
+
+ return;
+
+checksum_fail:
+ vsi->back->hw_csum_rx_error++;
+}
+
+/**
+ * i40e_rx_hash - returns the hash value from the Rx descriptor
+ * @ring: descriptor ring
+ * @rx_desc: specific descriptor
+ **/
+static inline u32 i40e_rx_hash(struct i40e_ring *ring,
+ union i40e_rx_desc *rx_desc)
+{
+ const __le64 rss_mask =
+ cpu_to_le64((u64)I40E_RX_DESC_FLTSTAT_RSS_HASH <<
+ I40E_RX_DESC_STATUS_FLTSTAT_SHIFT);
+
+ if ((ring->netdev->features & NETIF_F_RXHASH) &&
+ (rx_desc->wb.qword1.status_error_len & rss_mask) == rss_mask)
+ return le32_to_cpu(rx_desc->wb.qword0.hi_dword.rss);
+ else
+ return 0;
+}
+
+/**
+ * i40e_ptype_to_hash - get a hash type
+ * @ptype: the ptype value from the descriptor
+ *
+ * Returns a hash type to be used by skb_set_hash
+ **/
+static inline enum pkt_hash_types i40e_ptype_to_hash(u8 ptype)
+{
+ struct i40e_rx_ptype_decoded decoded = decode_rx_desc_ptype(ptype);
+
+ if (!decoded.known)
+ return PKT_HASH_TYPE_NONE;
+
+ if (decoded.outer_ip == I40E_RX_PTYPE_OUTER_IP &&
+ decoded.payload_layer == I40E_RX_PTYPE_PAYLOAD_LAYER_PAY4)
+ return PKT_HASH_TYPE_L4;
+ else if (decoded.outer_ip == I40E_RX_PTYPE_OUTER_IP &&
+ decoded.payload_layer == I40E_RX_PTYPE_PAYLOAD_LAYER_PAY3)
+ return PKT_HASH_TYPE_L3;
+ else
+ return PKT_HASH_TYPE_L2;
+}
+
+/**
+ * i40e_clean_rx_irq_ps - Reclaim resources after receive; packet split
+ * @rx_ring: rx ring to clean
+ * @budget: how many cleans we're allowed
+ *
+ * Returns true if there's any budget left (e.g. the clean is finished)
+ **/
+static int i40e_clean_rx_irq_ps(struct i40e_ring *rx_ring, int budget)
+{
+ unsigned int total_rx_bytes = 0, total_rx_packets = 0;
+ u16 rx_packet_len, rx_header_len, rx_sph, rx_hbo;
+ u16 cleaned_count = I40E_DESC_UNUSED(rx_ring);
+ const int current_node = numa_node_id();
+ struct i40e_vsi *vsi = rx_ring->vsi;
+ u16 i = rx_ring->next_to_clean;
+ union i40e_rx_desc *rx_desc;
+ u32 rx_error, rx_status;
+ u8 rx_ptype;
+ u64 qword;
+
+ do {
+ struct i40e_rx_buffer *rx_bi;
+ struct sk_buff *skb;
+ u16 vlan_tag;
+ /* return some buffers to hardware, one at a time is too slow */
+ if (cleaned_count >= I40E_RX_BUFFER_WRITE) {
+ i40evf_alloc_rx_buffers_ps(rx_ring, cleaned_count);
+ cleaned_count = 0;
+ }
+
+ i = rx_ring->next_to_clean;
+ rx_desc = I40E_RX_DESC(rx_ring, i);
+ qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
+ rx_status = (qword & I40E_RXD_QW1_STATUS_MASK) >>
+ I40E_RXD_QW1_STATUS_SHIFT;
+
+ if (!(rx_status & (1 << I40E_RX_DESC_STATUS_DD_SHIFT)))
+ break;
+
+ /* This memory barrier is needed to keep us from reading
+ * any other fields out of the rx_desc until we know the
+ * DD bit is set.
+ */
+ dma_rmb();
+ rx_bi = &rx_ring->rx_bi[i];
+ skb = rx_bi->skb;
+ if (likely(!skb)) {
+ skb = netdev_alloc_skb_ip_align(rx_ring->netdev,
+ rx_ring->rx_hdr_len);
+ if (!skb) {
+ rx_ring->rx_stats.alloc_buff_failed++;
+ break;
+ }
+
+ /* initialize queue mapping */
+ skb_record_rx_queue(skb, rx_ring->queue_index);
+ /* we are reusing so sync this buffer for CPU use */
+ dma_sync_single_range_for_cpu(rx_ring->dev,
+ rx_bi->dma,
+ 0,
+ rx_ring->rx_hdr_len,
+ DMA_FROM_DEVICE);
+ }
+ rx_packet_len = (qword & I40E_RXD_QW1_LENGTH_PBUF_MASK) >>
+ I40E_RXD_QW1_LENGTH_PBUF_SHIFT;
+ rx_header_len = (qword & I40E_RXD_QW1_LENGTH_HBUF_MASK) >>
+ I40E_RXD_QW1_LENGTH_HBUF_SHIFT;
+ rx_sph = (qword & I40E_RXD_QW1_LENGTH_SPH_MASK) >>
+ I40E_RXD_QW1_LENGTH_SPH_SHIFT;
+
+ rx_error = (qword & I40E_RXD_QW1_ERROR_MASK) >>
+ I40E_RXD_QW1_ERROR_SHIFT;
+ rx_hbo = rx_error & (1 << I40E_RX_DESC_ERROR_HBO_SHIFT);
+ rx_error &= ~(1 << I40E_RX_DESC_ERROR_HBO_SHIFT);
+
+ rx_ptype = (qword & I40E_RXD_QW1_PTYPE_MASK) >>
+ I40E_RXD_QW1_PTYPE_SHIFT;
+ prefetch(rx_bi->page);
+ rx_bi->skb = NULL;
+ cleaned_count++;
+ if (rx_hbo || rx_sph) {
+ int len;
+ if (rx_hbo)
+ len = I40E_RX_HDR_SIZE;
+ else
+ len = rx_header_len;
+ memcpy(__skb_put(skb, len), rx_bi->hdr_buf, len);
+ } else if (skb->len == 0) {
+ int len;
+
+ len = (rx_packet_len > skb_headlen(skb) ?
+ skb_headlen(skb) : rx_packet_len);
+ memcpy(__skb_put(skb, len),
+ rx_bi->page + rx_bi->page_offset,
+ len);
+ rx_bi->page_offset += len;
+ rx_packet_len -= len;
+ }
+
+ /* Get the rest of the data if this was a header split */
+ if (rx_packet_len) {
+ skb_fill_page_desc(skb, skb_shinfo(skb)->nr_frags,
+ rx_bi->page,
+ rx_bi->page_offset,
+ rx_packet_len);
+
+ skb->len += rx_packet_len;
+ skb->data_len += rx_packet_len;
+ skb->truesize += rx_packet_len;
+
+ if ((page_count(rx_bi->page) == 1) &&
+ (page_to_nid(rx_bi->page) == current_node))
+ get_page(rx_bi->page);
+ else
+ rx_bi->page = NULL;
+
+ dma_unmap_page(rx_ring->dev,
+ rx_bi->page_dma,
+ PAGE_SIZE / 2,
+ DMA_FROM_DEVICE);
+ rx_bi->page_dma = 0;
+ }
+ I40E_RX_INCREMENT(rx_ring, i);
+
+ if (unlikely(
+ !(rx_status & (1 << I40E_RX_DESC_STATUS_EOF_SHIFT)))) {
+ struct i40e_rx_buffer *next_buffer;
+
+ next_buffer = &rx_ring->rx_bi[i];
+ next_buffer->skb = skb;
+ rx_ring->rx_stats.non_eop_descs++;
+ continue;
+ }
+
+ /* ERR_MASK will only have valid bits if EOP set */
+ if (unlikely(rx_error & (1 << I40E_RX_DESC_ERROR_RXE_SHIFT))) {
+ dev_kfree_skb_any(skb);
+ /* TODO: shouldn't we increment a counter indicating the
+ * drop?
+ */
+ continue;
+ }
+
+ skb_set_hash(skb, i40e_rx_hash(rx_ring, rx_desc),
+ i40e_ptype_to_hash(rx_ptype));
+ /* probably a little skewed due to removing CRC */
+ total_rx_bytes += skb->len;
+ total_rx_packets++;
+
+ skb->protocol = eth_type_trans(skb, rx_ring->netdev);
+
+ i40e_rx_checksum(vsi, skb, rx_status, rx_error, rx_ptype);
+
+ vlan_tag = rx_status & (1 << I40E_RX_DESC_STATUS_L2TAG1P_SHIFT)
+ ? le16_to_cpu(rx_desc->wb.qword0.lo_dword.l2tag1)
+ : 0;
+#ifdef I40E_FCOE
+ if (!i40e_fcoe_handle_offload(rx_ring, rx_desc, skb)) {
+ dev_kfree_skb_any(skb);
+ continue;
+ }
+#endif
+ skb_mark_napi_id(skb, &rx_ring->q_vector->napi);
+ i40e_receive_skb(rx_ring, skb, vlan_tag);
+
+ rx_ring->netdev->last_rx = jiffies;
+ rx_desc->wb.qword1.status_error_len = 0;
+
+ } while (likely(total_rx_packets < budget));
+
+ u64_stats_update_begin(&rx_ring->syncp);
+ rx_ring->stats.packets += total_rx_packets;
+ rx_ring->stats.bytes += total_rx_bytes;
+ u64_stats_update_end(&rx_ring->syncp);
+ rx_ring->q_vector->rx.total_packets += total_rx_packets;
+ rx_ring->q_vector->rx.total_bytes += total_rx_bytes;
+
+ return total_rx_packets;
+}
+
+/**
+ * i40e_clean_rx_irq_1buf - Reclaim resources after receive; single buffer
+ * @rx_ring: rx ring to clean
+ * @budget: how many cleans we're allowed
+ *
+ * Returns number of packets cleaned
+ **/
+static int i40e_clean_rx_irq_1buf(struct i40e_ring *rx_ring, int budget)
+{
+ unsigned int total_rx_bytes = 0, total_rx_packets = 0;
+ u16 cleaned_count = I40E_DESC_UNUSED(rx_ring);
+ struct i40e_vsi *vsi = rx_ring->vsi;
+ union i40e_rx_desc *rx_desc;
+ u32 rx_error, rx_status;
+ u16 rx_packet_len;
+ u8 rx_ptype;
+ u64 qword;
+ u16 i;
+
+ do {
+ struct i40e_rx_buffer *rx_bi;
+ struct sk_buff *skb;
+ u16 vlan_tag;
+ /* return some buffers to hardware, one at a time is too slow */
+ if (cleaned_count >= I40E_RX_BUFFER_WRITE) {
+ i40evf_alloc_rx_buffers_1buf(rx_ring, cleaned_count);
+ cleaned_count = 0;
+ }
+
+ i = rx_ring->next_to_clean;
+ rx_desc = I40E_RX_DESC(rx_ring, i);
+ qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
+ rx_status = (qword & I40E_RXD_QW1_STATUS_MASK) >>
+ I40E_RXD_QW1_STATUS_SHIFT;
+
+ if (!(rx_status & (1 << I40E_RX_DESC_STATUS_DD_SHIFT)))
+ break;
+
+ /* This memory barrier is needed to keep us from reading
+ * any other fields out of the rx_desc until we know the
+ * DD bit is set.
+ */
+ dma_rmb();
+
+ rx_bi = &rx_ring->rx_bi[i];
+ skb = rx_bi->skb;
+ prefetch(skb->data);
+
+ rx_packet_len = (qword & I40E_RXD_QW1_LENGTH_PBUF_MASK) >>
+ I40E_RXD_QW1_LENGTH_PBUF_SHIFT;
+
+ rx_error = (qword & I40E_RXD_QW1_ERROR_MASK) >>
+ I40E_RXD_QW1_ERROR_SHIFT;
+ rx_error &= ~(1 << I40E_RX_DESC_ERROR_HBO_SHIFT);
+
+ rx_ptype = (qword & I40E_RXD_QW1_PTYPE_MASK) >>
+ I40E_RXD_QW1_PTYPE_SHIFT;
+ rx_bi->skb = NULL;
+ cleaned_count++;
+
+ /* Get the header and possibly the whole packet
+ * If this is an skb from previous receive dma will be 0
+ */
+ skb_put(skb, rx_packet_len);
+ dma_unmap_single(rx_ring->dev, rx_bi->dma, rx_ring->rx_buf_len,
+ DMA_FROM_DEVICE);
+ rx_bi->dma = 0;
+
+ I40E_RX_INCREMENT(rx_ring, i);
+
+ if (unlikely(
+ !(rx_status & (1 << I40E_RX_DESC_STATUS_EOF_SHIFT)))) {
+ rx_ring->rx_stats.non_eop_descs++;
+ continue;
+ }
+
+ /* ERR_MASK will only have valid bits if EOP set */
+ if (unlikely(rx_error & (1 << I40E_RX_DESC_ERROR_RXE_SHIFT))) {
+ dev_kfree_skb_any(skb);
+ /* TODO: shouldn't we increment a counter indicating the
+ * drop?
+ */
+ continue;
+ }
+
+ skb_set_hash(skb, i40e_rx_hash(rx_ring, rx_desc),
+ i40e_ptype_to_hash(rx_ptype));
+ /* probably a little skewed due to removing CRC */
+ total_rx_bytes += skb->len;
+ total_rx_packets++;
+
+ skb->protocol = eth_type_trans(skb, rx_ring->netdev);
+
+ i40e_rx_checksum(vsi, skb, rx_status, rx_error, rx_ptype);
+
+ vlan_tag = rx_status & (1 << I40E_RX_DESC_STATUS_L2TAG1P_SHIFT)
+ ? le16_to_cpu(rx_desc->wb.qword0.lo_dword.l2tag1)
+ : 0;
+ i40e_receive_skb(rx_ring, skb, vlan_tag);
+
+ rx_ring->netdev->last_rx = jiffies;
+ rx_desc->wb.qword1.status_error_len = 0;
+ } while (likely(total_rx_packets < budget));
+
+ u64_stats_update_begin(&rx_ring->syncp);
+ rx_ring->stats.packets += total_rx_packets;
+ rx_ring->stats.bytes += total_rx_bytes;
+ u64_stats_update_end(&rx_ring->syncp);
+ rx_ring->q_vector->rx.total_packets += total_rx_packets;
+ rx_ring->q_vector->rx.total_bytes += total_rx_bytes;
+
+ return total_rx_packets;
+}
+
+/**
+ * i40evf_napi_poll - NAPI polling Rx/Tx cleanup routine
+ * @napi: napi struct with our devices info in it
+ * @budget: amount of work driver is allowed to do this pass, in packets
+ *
+ * This function will clean all queues associated with a q_vector.
+ *
+ * Returns the amount of work done
+ **/
+int i40evf_napi_poll(struct napi_struct *napi, int budget)
+{
+ struct i40e_q_vector *q_vector =
+ container_of(napi, struct i40e_q_vector, napi);
+ struct i40e_vsi *vsi = q_vector->vsi;
+ struct i40e_ring *ring;
+ bool clean_complete = true;
+ bool arm_wb = false;
+ int budget_per_ring;
+ int cleaned;
+
+ if (test_bit(__I40E_DOWN, &vsi->state)) {
+ napi_complete(napi);
+ return 0;
+ }
+
+ /* Since the actual Tx work is minimal, we can give the Tx a larger
+ * budget and be more aggressive about cleaning up the Tx descriptors.
+ */
+ i40e_for_each_ring(ring, q_vector->tx) {
+ clean_complete &= i40e_clean_tx_irq(ring, vsi->work_limit);
+ arm_wb |= ring->arm_wb;
+ }
+
+ /* We attempt to distribute budget to each Rx queue fairly, but don't
+ * allow the budget to go below 1 because that would exit polling early.
+ */
+ budget_per_ring = max(budget/q_vector->num_ringpairs, 1);
+
+ i40e_for_each_ring(ring, q_vector->rx) {
+ if (ring_is_ps_enabled(ring))
+ cleaned = i40e_clean_rx_irq_ps(ring, budget_per_ring);
+ else
+ cleaned = i40e_clean_rx_irq_1buf(ring, budget_per_ring);
+ /* if we didn't clean as many as budgeted, we must be done */
+ clean_complete &= (budget_per_ring != cleaned);
+ }
+
+ /* If work not completed, return budget and polling will return */
+ if (!clean_complete) {
+ if (arm_wb)
+ i40e_force_wb(vsi, q_vector);
+ return budget;
+ }
+
+ /* Work is done so exit the polling mode and re-enable the interrupt */
+ napi_complete(napi);
+ if (ITR_IS_DYNAMIC(vsi->rx_itr_setting) ||
+ ITR_IS_DYNAMIC(vsi->tx_itr_setting))
+ i40e_update_dynamic_itr(q_vector);
+
+ if (!test_bit(__I40E_DOWN, &vsi->state))
+ i40evf_irq_enable_queues(vsi->back, 1 << q_vector->v_idx);
+
+ return 0;
+}
+
+/**
+ * i40e_tx_prepare_vlan_flags - prepare generic TX VLAN tagging flags for HW
+ * @skb: send buffer
+ * @tx_ring: ring to send buffer on
+ * @flags: the tx flags to be set
+ *
+ * Checks the skb and set up correspondingly several generic transmit flags
+ * related to VLAN tagging for the HW, such as VLAN, DCB, etc.
+ *
+ * Returns error code indicate the frame should be dropped upon error and the
+ * otherwise returns 0 to indicate the flags has been set properly.
+ **/
+static int i40e_tx_prepare_vlan_flags(struct sk_buff *skb,
+ struct i40e_ring *tx_ring,
+ u32 *flags)
+{
+ __be16 protocol = skb->protocol;
+ u32 tx_flags = 0;
+
+ if (protocol == htons(ETH_P_8021Q) &&
+ !(tx_ring->netdev->features & NETIF_F_HW_VLAN_CTAG_TX)) {
+ /* When HW VLAN acceleration is turned off by the user the
+ * stack sets the protocol to 8021q so that the driver
+ * can take any steps required to support the SW only
+ * VLAN handling. In our case the driver doesn't need
+ * to take any further steps so just set the protocol
+ * to the encapsulated ethertype.
+ */
+ skb->protocol = vlan_get_protocol(skb);
+ goto out;
+ }
+
+ /* if we have a HW VLAN tag being added, default to the HW one */
+ if (skb_vlan_tag_present(skb)) {
+ tx_flags |= skb_vlan_tag_get(skb) << I40E_TX_FLAGS_VLAN_SHIFT;
+ tx_flags |= I40E_TX_FLAGS_HW_VLAN;
+ /* else if it is a SW VLAN, check the next protocol and store the tag */
+ } else if (protocol == htons(ETH_P_8021Q)) {
+ struct vlan_hdr *vhdr, _vhdr;
+ vhdr = skb_header_pointer(skb, ETH_HLEN, sizeof(_vhdr), &_vhdr);
+ if (!vhdr)
+ return -EINVAL;
+
+ protocol = vhdr->h_vlan_encapsulated_proto;
+ tx_flags |= ntohs(vhdr->h_vlan_TCI) << I40E_TX_FLAGS_VLAN_SHIFT;
+ tx_flags |= I40E_TX_FLAGS_SW_VLAN;
+ }
+
+out:
+ *flags = tx_flags;
+ return 0;
+}
+
+/**
+ * i40e_tso - set up the tso context descriptor
+ * @tx_ring: ptr to the ring to send
+ * @skb: ptr to the skb we're sending
+ * @tx_flags: the collected send information
+ * @protocol: the send protocol
+ * @hdr_len: ptr to the size of the packet header
+ * @cd_tunneling: ptr to context descriptor bits
+ *
+ * Returns 0 if no TSO can happen, 1 if tso is going, or error
+ **/
+static int i40e_tso(struct i40e_ring *tx_ring, struct sk_buff *skb,
+ u32 tx_flags, __be16 protocol, u8 *hdr_len,
+ u64 *cd_type_cmd_tso_mss, u32 *cd_tunneling)
+{
+ u32 cd_cmd, cd_tso_len, cd_mss;
+ struct ipv6hdr *ipv6h;
+ struct tcphdr *tcph;
+ struct iphdr *iph;
+ u32 l4len;
+ int err;
+
+ if (!skb_is_gso(skb))
+ return 0;
+
+ err = skb_cow_head(skb, 0);
+ if (err < 0)
+ return err;
+
+ iph = skb->encapsulation ? inner_ip_hdr(skb) : ip_hdr(skb);
+ ipv6h = skb->encapsulation ? inner_ipv6_hdr(skb) : ipv6_hdr(skb);
+
+ if (iph->version == 4) {
+ tcph = skb->encapsulation ? inner_tcp_hdr(skb) : tcp_hdr(skb);
+ iph->tot_len = 0;
+ iph->check = 0;
+ tcph->check = ~csum_tcpudp_magic(iph->saddr, iph->daddr,
+ 0, IPPROTO_TCP, 0);
+ } else if (ipv6h->version == 6) {
+ tcph = skb->encapsulation ? inner_tcp_hdr(skb) : tcp_hdr(skb);
+ ipv6h->payload_len = 0;
+ tcph->check = ~csum_ipv6_magic(&ipv6h->saddr, &ipv6h->daddr,
+ 0, IPPROTO_TCP, 0);
+ }
+
+ l4len = skb->encapsulation ? inner_tcp_hdrlen(skb) : tcp_hdrlen(skb);
+ *hdr_len = (skb->encapsulation
+ ? (skb_inner_transport_header(skb) - skb->data)
+ : skb_transport_offset(skb)) + l4len;
+
+ /* find the field values */
+ cd_cmd = I40E_TX_CTX_DESC_TSO;
+ cd_tso_len = skb->len - *hdr_len;
+ cd_mss = skb_shinfo(skb)->gso_size;
+ *cd_type_cmd_tso_mss |= ((u64)cd_cmd << I40E_TXD_CTX_QW1_CMD_SHIFT) |
+ ((u64)cd_tso_len <<
+ I40E_TXD_CTX_QW1_TSO_LEN_SHIFT) |
+ ((u64)cd_mss << I40E_TXD_CTX_QW1_MSS_SHIFT);
+ return 1;
+}
+
+/**
+ * i40e_tx_enable_csum - Enable Tx checksum offloads
+ * @skb: send buffer
+ * @tx_flags: Tx flags currently set
+ * @td_cmd: Tx descriptor command bits to set
+ * @td_offset: Tx descriptor header offsets to set
+ * @cd_tunneling: ptr to context desc bits
+ **/
+static void i40e_tx_enable_csum(struct sk_buff *skb, u32 tx_flags,
+ u32 *td_cmd, u32 *td_offset,
+ struct i40e_ring *tx_ring,
+ u32 *cd_tunneling)
+{
+ struct ipv6hdr *this_ipv6_hdr;
+ unsigned int this_tcp_hdrlen;
+ struct iphdr *this_ip_hdr;
+ u32 network_hdr_len;
+ u8 l4_hdr = 0;
+ u32 l4_tunnel = 0;
+
+ if (skb->encapsulation) {
+ switch (ip_hdr(skb)->protocol) {
+ case IPPROTO_UDP:
+ l4_tunnel = I40E_TXD_CTX_UDP_TUNNELING;
+ break;
+ default:
+ return;
+ }
+ network_hdr_len = skb_inner_network_header_len(skb);
+ this_ip_hdr = inner_ip_hdr(skb);
+ this_ipv6_hdr = inner_ipv6_hdr(skb);
+ this_tcp_hdrlen = inner_tcp_hdrlen(skb);
+
+ if (tx_flags & I40E_TX_FLAGS_IPV4) {
+
+ if (tx_flags & I40E_TX_FLAGS_TSO) {
+ *cd_tunneling |= I40E_TX_CTX_EXT_IP_IPV4;
+ ip_hdr(skb)->check = 0;
+ } else {
+ *cd_tunneling |=
+ I40E_TX_CTX_EXT_IP_IPV4_NO_CSUM;
+ }
+ } else if (tx_flags & I40E_TX_FLAGS_IPV6) {
+ *cd_tunneling |= I40E_TX_CTX_EXT_IP_IPV6;
+ if (tx_flags & I40E_TX_FLAGS_TSO)
+ ip_hdr(skb)->check = 0;
+ }
+
+ /* Now set the ctx descriptor fields */
+ *cd_tunneling |= (skb_network_header_len(skb) >> 2) <<
+ I40E_TXD_CTX_QW0_EXT_IPLEN_SHIFT |
+ l4_tunnel |
+ ((skb_inner_network_offset(skb) -
+ skb_transport_offset(skb)) >> 1) <<
+ I40E_TXD_CTX_QW0_NATLEN_SHIFT;
+ if (this_ip_hdr->version == 6) {
+ tx_flags &= ~I40E_TX_FLAGS_IPV4;
+ tx_flags |= I40E_TX_FLAGS_IPV6;
+ }
+
+
+ } else {
+ network_hdr_len = skb_network_header_len(skb);
+ this_ip_hdr = ip_hdr(skb);
+ this_ipv6_hdr = ipv6_hdr(skb);
+ this_tcp_hdrlen = tcp_hdrlen(skb);
+ }
+
+ /* Enable IP checksum offloads */
+ if (tx_flags & I40E_TX_FLAGS_IPV4) {
+ l4_hdr = this_ip_hdr->protocol;
+ /* the stack computes the IP header already, the only time we
+ * need the hardware to recompute it is in the case of TSO.
+ */
+ if (tx_flags & I40E_TX_FLAGS_TSO) {
+ *td_cmd |= I40E_TX_DESC_CMD_IIPT_IPV4_CSUM;
+ this_ip_hdr->check = 0;
+ } else {
+ *td_cmd |= I40E_TX_DESC_CMD_IIPT_IPV4;
+ }
+ /* Now set the td_offset for IP header length */
+ *td_offset = (network_hdr_len >> 2) <<
+ I40E_TX_DESC_LENGTH_IPLEN_SHIFT;
+ } else if (tx_flags & I40E_TX_FLAGS_IPV6) {
+ l4_hdr = this_ipv6_hdr->nexthdr;
+ *td_cmd |= I40E_TX_DESC_CMD_IIPT_IPV6;
+ /* Now set the td_offset for IP header length */
+ *td_offset = (network_hdr_len >> 2) <<
+ I40E_TX_DESC_LENGTH_IPLEN_SHIFT;
+ }
+ /* words in MACLEN + dwords in IPLEN + dwords in L4Len */
+ *td_offset |= (skb_network_offset(skb) >> 1) <<
+ I40E_TX_DESC_LENGTH_MACLEN_SHIFT;
+
+ /* Enable L4 checksum offloads */
+ switch (l4_hdr) {
+ case IPPROTO_TCP:
+ /* enable checksum offloads */
+ *td_cmd |= I40E_TX_DESC_CMD_L4T_EOFT_TCP;
+ *td_offset |= (this_tcp_hdrlen >> 2) <<
+ I40E_TX_DESC_LENGTH_L4_FC_LEN_SHIFT;
+ break;
+ case IPPROTO_SCTP:
+ /* enable SCTP checksum offload */
+ *td_cmd |= I40E_TX_DESC_CMD_L4T_EOFT_SCTP;
+ *td_offset |= (sizeof(struct sctphdr) >> 2) <<
+ I40E_TX_DESC_LENGTH_L4_FC_LEN_SHIFT;
+ break;
+ case IPPROTO_UDP:
+ /* enable UDP checksum offload */
+ *td_cmd |= I40E_TX_DESC_CMD_L4T_EOFT_UDP;
+ *td_offset |= (sizeof(struct udphdr) >> 2) <<
+ I40E_TX_DESC_LENGTH_L4_FC_LEN_SHIFT;
+ break;
+ default:
+ break;
+ }
+}
+
+/**
+ * i40e_create_tx_ctx Build the Tx context descriptor
+ * @tx_ring: ring to create the descriptor on
+ * @cd_type_cmd_tso_mss: Quad Word 1
+ * @cd_tunneling: Quad Word 0 - bits 0-31
+ * @cd_l2tag2: Quad Word 0 - bits 32-63
+ **/
+static void i40e_create_tx_ctx(struct i40e_ring *tx_ring,
+ const u64 cd_type_cmd_tso_mss,
+ const u32 cd_tunneling, const u32 cd_l2tag2)
+{
+ struct i40e_tx_context_desc *context_desc;
+ int i = tx_ring->next_to_use;
+
+ if ((cd_type_cmd_tso_mss == I40E_TX_DESC_DTYPE_CONTEXT) &&
+ !cd_tunneling && !cd_l2tag2)
+ return;
+
+ /* grab the next descriptor */
+ context_desc = I40E_TX_CTXTDESC(tx_ring, i);
+
+ i++;
+ tx_ring->next_to_use = (i < tx_ring->count) ? i : 0;
+
+ /* cpu_to_le32 and assign to struct fields */
+ context_desc->tunneling_params = cpu_to_le32(cd_tunneling);
+ context_desc->l2tag2 = cpu_to_le16(cd_l2tag2);
+ context_desc->rsvd = cpu_to_le16(0);
+ context_desc->type_cmd_tso_mss = cpu_to_le64(cd_type_cmd_tso_mss);
+}
+
+ /**
+ * i40e_chk_linearize - Check if there are more than 8 fragments per packet
+ * @skb: send buffer
+ * @tx_flags: collected send information
+ *
+ * Note: Our HW can't scatter-gather more than 8 fragments to build
+ * a packet on the wire and so we need to figure out the cases where we
+ * need to linearize the skb.
+ **/
+static bool i40e_chk_linearize(struct sk_buff *skb, u32 tx_flags)
+{
+ struct skb_frag_struct *frag;
+ bool linearize = false;
+ unsigned int size = 0;
+ u16 num_frags;
+ u16 gso_segs;
+
+ num_frags = skb_shinfo(skb)->nr_frags;
+ gso_segs = skb_shinfo(skb)->gso_segs;
+
+ if (tx_flags & (I40E_TX_FLAGS_TSO | I40E_TX_FLAGS_FSO)) {
+ u16 j = 0;
+
+ if (num_frags < (I40E_MAX_BUFFER_TXD))
+ goto linearize_chk_done;
+ /* try the simple math, if we have too many frags per segment */
+ if (DIV_ROUND_UP((num_frags + gso_segs), gso_segs) >
+ I40E_MAX_BUFFER_TXD) {
+ linearize = true;
+ goto linearize_chk_done;
+ }
+ frag = &skb_shinfo(skb)->frags[0];
+ /* we might still have more fragments per segment */
+ do {
+ size += skb_frag_size(frag);
+ frag++; j++;
+ if ((size >= skb_shinfo(skb)->gso_size) &&
+ (j < I40E_MAX_BUFFER_TXD)) {
+ size = (size % skb_shinfo(skb)->gso_size);
+ j = (size) ? 1 : 0;
+ }
+ if (j == I40E_MAX_BUFFER_TXD) {
+ linearize = true;
+ break;
+ }
+ num_frags--;
+ } while (num_frags);
+ } else {
+ if (num_frags >= I40E_MAX_BUFFER_TXD)
+ linearize = true;
+ }
+
+linearize_chk_done:
+ return linearize;
+}
+
+/**
+ * i40e_tx_map - Build the Tx descriptor
+ * @tx_ring: ring to send buffer on
+ * @skb: send buffer
+ * @first: first buffer info buffer to use
+ * @tx_flags: collected send information
+ * @hdr_len: size of the packet header
+ * @td_cmd: the command field in the descriptor
+ * @td_offset: offset for checksum or crc
+ **/
+static void i40e_tx_map(struct i40e_ring *tx_ring, struct sk_buff *skb,
+ struct i40e_tx_buffer *first, u32 tx_flags,
+ const u8 hdr_len, u32 td_cmd, u32 td_offset)
+{
+ unsigned int data_len = skb->data_len;
+ unsigned int size = skb_headlen(skb);
+ struct skb_frag_struct *frag;
+ struct i40e_tx_buffer *tx_bi;
+ struct i40e_tx_desc *tx_desc;
+ u16 i = tx_ring->next_to_use;
+ u32 td_tag = 0;
+ dma_addr_t dma;
+ u16 gso_segs;
+
+ if (tx_flags & I40E_TX_FLAGS_HW_VLAN) {
+ td_cmd |= I40E_TX_DESC_CMD_IL2TAG1;
+ td_tag = (tx_flags & I40E_TX_FLAGS_VLAN_MASK) >>
+ I40E_TX_FLAGS_VLAN_SHIFT;
+ }
+
+ if (tx_flags & (I40E_TX_FLAGS_TSO | I40E_TX_FLAGS_FSO))
+ gso_segs = skb_shinfo(skb)->gso_segs;
+ else
+ gso_segs = 1;
+
+ /* multiply data chunks by size of headers */
+ first->bytecount = skb->len - hdr_len + (gso_segs * hdr_len);
+ first->gso_segs = gso_segs;
+ first->skb = skb;
+ first->tx_flags = tx_flags;
+
+ dma = dma_map_single(tx_ring->dev, skb->data, size, DMA_TO_DEVICE);
+
+ tx_desc = I40E_TX_DESC(tx_ring, i);
+ tx_bi = 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_bi, len, size);
+ dma_unmap_addr_set(tx_bi, dma, dma);
+
+ tx_desc->buffer_addr = cpu_to_le64(dma);
+
+ while (unlikely(size > I40E_MAX_DATA_PER_TXD)) {
+ tx_desc->cmd_type_offset_bsz =
+ build_ctob(td_cmd, td_offset,
+ I40E_MAX_DATA_PER_TXD, td_tag);
+
+ tx_desc++;
+ i++;
+ if (i == tx_ring->count) {
+ tx_desc = I40E_TX_DESC(tx_ring, 0);
+ i = 0;
+ }
+
+ dma += I40E_MAX_DATA_PER_TXD;
+ size -= I40E_MAX_DATA_PER_TXD;
+
+ tx_desc->buffer_addr = cpu_to_le64(dma);
+ }
+
+ if (likely(!data_len))
+ break;
+
+ tx_desc->cmd_type_offset_bsz = build_ctob(td_cmd, td_offset,
+ size, td_tag);
+
+ tx_desc++;
+ i++;
+ if (i == tx_ring->count) {
+ tx_desc = I40E_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_bi = &tx_ring->tx_bi[i];
+ }
+
+ /* Place RS bit on last descriptor of any packet that spans across the
+ * 4th descriptor (WB_STRIDE aka 0x3) in a 64B cacheline.
+ */
+#define WB_STRIDE 0x3
+ if (((i & WB_STRIDE) != WB_STRIDE) &&
+ (first <= &tx_ring->tx_bi[i]) &&
+ (first >= &tx_ring->tx_bi[i & ~WB_STRIDE])) {
+ tx_desc->cmd_type_offset_bsz =
+ build_ctob(td_cmd, td_offset, size, td_tag) |
+ cpu_to_le64((u64)I40E_TX_DESC_CMD_EOP <<
+ I40E_TXD_QW1_CMD_SHIFT);
+ } else {
+ tx_desc->cmd_type_offset_bsz =
+ build_ctob(td_cmd, td_offset, size, td_tag) |
+ cpu_to_le64((u64)I40E_TXD_CMD <<
+ I40E_TXD_QW1_CMD_SHIFT);
+ }
+
+ netdev_tx_sent_queue(netdev_get_tx_queue(tx_ring->netdev,
+ tx_ring->queue_index),
+ first->bytecount);
+
+ /* set the timestamp */
+ first->time_stamp = jiffies;
+
+ /* 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();
+
+ /* set next_to_watch value indicating a packet is present */
+ first->next_to_watch = tx_desc;
+
+ i++;
+ if (i == tx_ring->count)
+ i = 0;
+
+ tx_ring->next_to_use = i;
+
+ /* notify HW of packet */
+ writel(i, tx_ring->tail);
+
+ return;
+
+dma_error:
+ dev_info(tx_ring->dev, "TX DMA map failed\n");
+
+ /* clear dma mappings for failed tx_bi map */
+ for (;;) {
+ tx_bi = &tx_ring->tx_bi[i];
+ i40e_unmap_and_free_tx_resource(tx_ring, tx_bi);
+ if (tx_bi == first)
+ break;
+ if (i == 0)
+ i = tx_ring->count;
+ i--;
+ }
+
+ tx_ring->next_to_use = i;
+}
+
+/**
+ * __i40e_maybe_stop_tx - 2nd level check for tx stop conditions
+ * @tx_ring: the ring to be checked
+ * @size: the size buffer we want to assure is available
+ *
+ * Returns -EBUSY if a stop is needed, else 0
+ **/
+static inline int __i40e_maybe_stop_tx(struct i40e_ring *tx_ring, int size)
+{
+ netif_stop_subqueue(tx_ring->netdev, tx_ring->queue_index);
+ /* Memory barrier before checking head and tail */
+ smp_mb();
+
+ /* Check again in a case another CPU has just made room available. */
+ if (likely(I40E_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;
+}
+
+/**
+ * i40e_maybe_stop_tx - 1st level check for tx stop conditions
+ * @tx_ring: the ring to be checked
+ * @size: the size buffer we want to assure is available
+ *
+ * Returns 0 if stop is not needed
+ **/
+static int i40e_maybe_stop_tx(struct i40e_ring *tx_ring, int size)
+{
+ if (likely(I40E_DESC_UNUSED(tx_ring) >= size))
+ return 0;
+ return __i40e_maybe_stop_tx(tx_ring, size);
+}
+
+/**
+ * i40e_xmit_descriptor_count - calculate number of tx descriptors needed
+ * @skb: send buffer
+ * @tx_ring: ring to send buffer on
+ *
+ * Returns number of data descriptors needed for this skb. Returns 0 to indicate
+ * there is not enough descriptors available in this ring since we need at least
+ * one descriptor.
+ **/
+static int i40e_xmit_descriptor_count(struct sk_buff *skb,
+ struct i40e_ring *tx_ring)
+{
+ unsigned int f;
+ int count = 0;
+
+ /* need: 1 descriptor per page * PAGE_SIZE/I40E_MAX_DATA_PER_TXD,
+ * + 1 desc for skb_head_len/I40E_MAX_DATA_PER_TXD,
+ * + 4 desc gap to avoid the cache line where head is,
+ * + 1 desc for context descriptor,
+ * otherwise try next time
+ */
+ for (f = 0; f < skb_shinfo(skb)->nr_frags; f++)
+ count += TXD_USE_COUNT(skb_shinfo(skb)->frags[f].size);
+
+ count += TXD_USE_COUNT(skb_headlen(skb));
+ if (i40e_maybe_stop_tx(tx_ring, count + 4 + 1)) {
+ tx_ring->tx_stats.tx_busy++;
+ return 0;
+ }
+ return count;
+}
+
+/**
+ * i40e_xmit_frame_ring - Sends buffer on Tx ring
+ * @skb: send buffer
+ * @tx_ring: ring to send buffer on
+ *
+ * Returns NETDEV_TX_OK if sent, else an error code
+ **/
+static netdev_tx_t i40e_xmit_frame_ring(struct sk_buff *skb,
+ struct i40e_ring *tx_ring)
+{
+ u64 cd_type_cmd_tso_mss = I40E_TX_DESC_DTYPE_CONTEXT;
+ u32 cd_tunneling = 0, cd_l2tag2 = 0;
+ struct i40e_tx_buffer *first;
+ u32 td_offset = 0;
+ u32 tx_flags = 0;
+ __be16 protocol;
+ u32 td_cmd = 0;
+ u8 hdr_len = 0;
+ int tso;
+ if (0 == i40e_xmit_descriptor_count(skb, tx_ring))
+ return NETDEV_TX_BUSY;
+
+ /* prepare the xmit flags */
+ if (i40e_tx_prepare_vlan_flags(skb, tx_ring, &tx_flags))
+ goto out_drop;
+
+ /* obtain protocol of skb */
+ protocol = vlan_get_protocol(skb);
+
+ /* record the location of the first descriptor for this packet */
+ first = &tx_ring->tx_bi[tx_ring->next_to_use];
+
+ /* setup IPv4/IPv6 offloads */
+ if (protocol == htons(ETH_P_IP))
+ tx_flags |= I40E_TX_FLAGS_IPV4;
+ else if (protocol == htons(ETH_P_IPV6))
+ tx_flags |= I40E_TX_FLAGS_IPV6;
+
+ tso = i40e_tso(tx_ring, skb, tx_flags, protocol, &hdr_len,
+ &cd_type_cmd_tso_mss, &cd_tunneling);
+
+ if (tso < 0)
+ goto out_drop;
+ else if (tso)
+ tx_flags |= I40E_TX_FLAGS_TSO;
+
+ if (i40e_chk_linearize(skb, tx_flags))
+ if (skb_linearize(skb))
+ goto out_drop;
+
+ skb_tx_timestamp(skb);
+
+ /* always enable CRC insertion offload */
+ td_cmd |= I40E_TX_DESC_CMD_ICRC;
+
+ /* Always offload the checksum, since it's in the data descriptor */
+ if (skb->ip_summed == CHECKSUM_PARTIAL) {
+ tx_flags |= I40E_TX_FLAGS_CSUM;
+
+ i40e_tx_enable_csum(skb, tx_flags, &td_cmd, &td_offset,
+ tx_ring, &cd_tunneling);
+ }
+
+ i40e_create_tx_ctx(tx_ring, cd_type_cmd_tso_mss,
+ cd_tunneling, cd_l2tag2);
+
+ i40e_tx_map(tx_ring, skb, first, tx_flags, hdr_len,
+ td_cmd, td_offset);
+
+ i40e_maybe_stop_tx(tx_ring, DESC_NEEDED);
+
+ return NETDEV_TX_OK;
+
+out_drop:
+ dev_kfree_skb_any(skb);
+ return NETDEV_TX_OK;
+}
+
+/**
+ * i40evf_xmit_frame - Selects the correct VSI and Tx queue to send buffer
+ * @skb: send buffer
+ * @netdev: network interface device structure
+ *
+ * Returns NETDEV_TX_OK if sent, else an error code
+ **/
+netdev_tx_t i40evf_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
+{
+ struct i40evf_adapter *adapter = netdev_priv(netdev);
+ struct i40e_ring *tx_ring = adapter->tx_rings[skb->queue_mapping];
+
+ /* hardware can't handle really short frames, hardware padding works
+ * beyond this point
+ */
+ if (unlikely(skb->len < I40E_MIN_TX_LEN)) {
+ if (skb_pad(skb, I40E_MIN_TX_LEN - skb->len))
+ return NETDEV_TX_OK;
+ skb->len = I40E_MIN_TX_LEN;
+ skb_set_tail_pointer(skb, I40E_MIN_TX_LEN);
+ }
+
+ return i40e_xmit_frame_ring(skb, tx_ring);
+}
Code Review / kvmfornfv.git / blobdiff