/******************************************************************************* * * 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 . * * The full GNU General Public License is included in this distribution in * the file called "COPYING". * * Contact Information: * e1000-devel Mailing List * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497 * ******************************************************************************/ #include #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) { 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_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_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); } /* 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); /* 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; /* 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 extension 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_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 - 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; u8 rx_ptype; u64 qword; 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_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; 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 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; 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 == 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->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]; } /* 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 = 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); }