diff options
| -rw-r--r-- | drivers/net/ethernet/intel/i40evf/i40e_txrx.c | 1573 |
1 files changed, 1573 insertions, 0 deletions
diff --git a/drivers/net/ethernet/intel/i40evf/i40e_txrx.c b/drivers/net/ethernet/intel/i40evf/i40e_txrx.c new file mode 100644 index 000000000000..8f2b3b2a2a90 --- /dev/null +++ b/drivers/net/ethernet/intel/i40evf/i40e_txrx.c @@ -0,0 +1,1573 @@ +/******************************************************************************* + * + * Intel Ethernet Controller XL710 Family Linux Virtual Function Driver + * Copyright(c) 2013 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. + * + * 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 "i40evf.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) { + 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_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 ntu = ((ring->next_to_clean <= ring->next_to_use) + ? ring->next_to_use + : ring->next_to_use + ring->count); + return ntu - ring->next_to_clean; +} + +/** + * 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_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_ring->tx_stats.tx_done_old == tx_ring->stats.packets) && + 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 { + /* update completed stats and disarm the hang check */ + tx_ring->tx_stats.tx_done_old = tx_ring->stats.packets; + clear_bit(__I40E_HANG_CHECK_ARMED, &tx_ring->state); + } + + return ret; +} + +/** + * 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_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; + + 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(); + + /* if the descriptor isn't done, no work yet to do */ + if (!(eop_desc->cmd_type_offset_bsz & + cpu_to_le64(I40E_TX_DESC_DTYPE_DESC_DONE))) + 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); + } + + /* 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 (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_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); + 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; + + /* 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_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; + + /* 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 - 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(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; + } + } + + if (ring_is_ps_enabled(rx_ring)) { + 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; + } + } + + /* 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); + } else { + 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) +{ + bool ipv4_tunnel, ipv6_tunnel; + __wsum rx_udp_csum; + __sum16 csum; + struct iphdr *iph; + + 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->encapsulation = ipv4_tunnel || ipv6_tunnel; + skb->ip_summed = CHECKSUM_NONE; + + /* Rx csum enabled and ip headers found? */ + if (!(vsi->netdev->features & NETIF_F_RXCSUM && + rx_status & (1 << I40E_RX_DESC_STATUS_L3L4P_SHIFT))) + return; + + /* likely incorrect csum if alternate IP extention headers found */ + if (rx_status & (1 << I40E_RX_DESC_STATUS_IPV6EXADD_SHIFT)) + return; + + /* IP or L4 or outmost IP checksum error */ + if (rx_error & ((1 << I40E_RX_DESC_ERROR_IPE_SHIFT) | + (1 << I40E_RX_DESC_ERROR_L4E_SHIFT) | + (1 << I40E_RX_DESC_ERROR_EIPE_SHIFT))) { + vsi->back->hw_csum_rx_error++; + return; + } + + if (ipv4_tunnel && + !(rx_status & (1 << I40E_RX_DESC_STATUS_UDP_0_SHIFT))) { + /* 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 + */ + 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; + + 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) { + vsi->back->hw_csum_rx_error++; + return; + } + } + + skb->ip_summed = CHECKSUM_UNNECESSARY; +} + +/** + * 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_clean_rx_irq - Reclaim resources after receive completes + * @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(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; + u64 qword; + u16 rx_ptype; + + 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; + + while (rx_status & (1 << I40E_RX_DESC_STATUS_DD_SHIFT)) { + union i40e_rx_desc *next_rxd; + struct i40e_rx_buffer *rx_bi; + struct sk_buff *skb; + u16 vlan_tag; + 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_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; + rx_bi->skb = NULL; + + /* This memory barrier is needed to keep us from reading + * any other fields out of the rx_desc until we know the + * STATUS_DD bit is set + */ + rmb(); + + /* Get the header and possibly the whole packet + * If this is an skb from previous receive dma will be 0 + */ + if (rx_bi->dma) { + u16 len; + + if (rx_hbo) + len = I40E_RX_HDR_SIZE; + else if (rx_sph) + len = rx_header_len; + else if (rx_packet_len) + len = rx_packet_len; /* 1buf/no split found */ + else + len = rx_header_len; /* split always mode */ + + skb_put(skb, len); + dma_unmap_single(rx_ring->dev, + rx_bi->dma, + rx_ring->rx_buf_len, + DMA_FROM_DEVICE); + rx_bi->dma = 0; + } + + /* Get the rest of the data if this was a header split */ + if (ring_is_ps_enabled(rx_ring) && 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_NEXT_DESC_PREFETCH(rx_ring, i, next_rxd); + + if (unlikely( + !(rx_status & (1 << I40E_RX_DESC_STATUS_EOF_SHIFT)))) { + struct i40e_rx_buffer *next_buffer; + + next_buffer = &rx_ring->rx_bi[i]; + + if (ring_is_ps_enabled(rx_ring)) { + rx_bi->skb = next_buffer->skb; + rx_bi->dma = next_buffer->dma; + next_buffer->skb = skb; + next_buffer->dma = 0; + } + rx_ring->rx_stats.non_eop_descs++; + goto next_desc; + } + + /* 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); + goto next_desc; + } + + skb->rxhash = i40e_rx_hash(rx_ring, rx_desc); + /* 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; + budget--; +next_desc: + rx_desc->wb.qword1.status_error_len = 0; + if (!budget) + break; + + cleaned_count++; + /* return some buffers to hardware, one at a time is too slow */ + if (cleaned_count >= I40E_RX_BUFFER_WRITE) { + i40evf_alloc_rx_buffers(rx_ring, cleaned_count); + cleaned_count = 0; + } + + /* use prefetched values */ + rx_desc = next_rxd; + qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len); + rx_status = (qword & I40E_RXD_QW1_STATUS_MASK) >> + I40E_RXD_QW1_STATUS_SHIFT; + } + + rx_ring->next_to_clean = i; + 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; + + if (cleaned_count) + i40evf_alloc_rx_buffers(rx_ring, cleaned_count); + + return budget > 0; +} + +/** + * 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; + int budget_per_ring; + + 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); + + /* 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) + clean_complete &= i40e_clean_rx_irq(ring, budget_per_ring); + + /* If work not completed, return budget and polling will return */ + if (!clean_complete) + 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 we have a HW VLAN tag being added, default to the HW one */ + if (vlan_tx_tag_present(skb)) { + tx_flags |= vlan_tx_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; + } + + *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 tcphdr *tcph; + struct iphdr *iph; + u32 l4len; + int err; + struct ipv6hdr *ipv6h; + + if (!skb_is_gso(skb)) + return 0; + + if (skb_header_cloned(skb)) { + err = pskb_expand_head(skb, 0, 0, GFP_ATOMIC); + if (err) + return err; + } + + if (protocol == htons(ETH_P_IP)) { + iph = skb->encapsulation ? inner_ip_hdr(skb) : ip_hdr(skb); + 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 (skb_is_gso_v6(skb)) { + + ipv6h = skb->encapsulation ? inner_ipv6_hdr(skb) + : ipv6_hdr(skb); + 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; + + if (skb->encapsulation) { + 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) { + if (tx_flags & I40E_TX_FLAGS_TSO) { + *cd_tunneling |= I40E_TX_CTX_EXT_IP_IPV6; + ip_hdr(skb)->check = 0; + } else { + *cd_tunneling |= + I40E_TX_CTX_EXT_IP_IPV4_NO_CSUM; + } + } + + /* Now set the ctx descriptor fields */ + *cd_tunneling |= (skb_network_header_len(skb) >> 2) << + I40E_TXD_CTX_QW0_EXT_IPLEN_SHIFT | + I40E_TXD_CTX_UDP_TUNNELING | + ((skb_inner_network_offset(skb) - + skb_transport_offset(skb)) >> 1) << + I40E_TXD_CTX_QW0_NATLEN_SHIFT; + + } 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 && !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->type_cmd_tso_mss = cpu_to_le64(cd_type_cmd_tso_mss); +} + +/** + * 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]; + } + + 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) +{ +#if PAGE_SIZE > I40E_MAX_DATA_PER_TXD + unsigned int f; +#endif + 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, + * + 2 desc gap to keep tail from touching head, + * + 1 desc for context descriptor, + * otherwise try next time + */ +#if PAGE_SIZE > I40E_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 + count += TXD_USE_COUNT(skb_headlen(skb)); + if (i40e_maybe_stop_tx(tx_ring, count + 3)) { + 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 = skb->protocol; + + /* 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; + + 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); +} |