diff options
Diffstat (limited to 'drivers/net/ethernet/pensando/ionic/ionic_txrx.c')
| -rw-r--r-- | drivers/net/ethernet/pensando/ionic/ionic_txrx.c | 925 |
1 files changed, 925 insertions, 0 deletions
diff --git a/drivers/net/ethernet/pensando/ionic/ionic_txrx.c b/drivers/net/ethernet/pensando/ionic/ionic_txrx.c new file mode 100644 index 000000000000..ab6663d94f42 --- /dev/null +++ b/drivers/net/ethernet/pensando/ionic/ionic_txrx.c @@ -0,0 +1,925 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright(c) 2017 - 2019 Pensando Systems, Inc */ + +#include <linux/ip.h> +#include <linux/ipv6.h> +#include <linux/if_vlan.h> +#include <net/ip6_checksum.h> + +#include "ionic.h" +#include "ionic_lif.h" +#include "ionic_txrx.h" + +static void ionic_rx_clean(struct ionic_queue *q, struct ionic_desc_info *desc_info, + struct ionic_cq_info *cq_info, void *cb_arg); + +static inline void ionic_txq_post(struct ionic_queue *q, bool ring_dbell, + ionic_desc_cb cb_func, void *cb_arg) +{ + DEBUG_STATS_TXQ_POST(q_to_qcq(q), q->head->desc, ring_dbell); + + ionic_q_post(q, ring_dbell, cb_func, cb_arg); +} + +static inline void ionic_rxq_post(struct ionic_queue *q, bool ring_dbell, + ionic_desc_cb cb_func, void *cb_arg) +{ + ionic_q_post(q, ring_dbell, cb_func, cb_arg); + + DEBUG_STATS_RX_BUFF_CNT(q_to_qcq(q)); +} + +static inline struct netdev_queue *q_to_ndq(struct ionic_queue *q) +{ + return netdev_get_tx_queue(q->lif->netdev, q->index); +} + +static void ionic_rx_recycle(struct ionic_queue *q, struct ionic_desc_info *desc_info, + struct sk_buff *skb) +{ + struct ionic_rxq_desc *old = desc_info->desc; + struct ionic_rxq_desc *new = q->head->desc; + + new->addr = old->addr; + new->len = old->len; + + ionic_rxq_post(q, true, ionic_rx_clean, skb); +} + +static bool ionic_rx_copybreak(struct ionic_queue *q, struct ionic_desc_info *desc_info, + struct ionic_cq_info *cq_info, struct sk_buff **skb) +{ + struct ionic_rxq_comp *comp = cq_info->cq_desc; + struct ionic_rxq_desc *desc = desc_info->desc; + struct net_device *netdev = q->lif->netdev; + struct device *dev = q->lif->ionic->dev; + struct sk_buff *new_skb; + u16 clen, dlen; + + clen = le16_to_cpu(comp->len); + dlen = le16_to_cpu(desc->len); + if (clen > q->lif->rx_copybreak) { + dma_unmap_single(dev, (dma_addr_t)le64_to_cpu(desc->addr), + dlen, DMA_FROM_DEVICE); + return false; + } + + new_skb = netdev_alloc_skb_ip_align(netdev, clen); + if (!new_skb) { + dma_unmap_single(dev, (dma_addr_t)le64_to_cpu(desc->addr), + dlen, DMA_FROM_DEVICE); + return false; + } + + dma_sync_single_for_cpu(dev, (dma_addr_t)le64_to_cpu(desc->addr), + clen, DMA_FROM_DEVICE); + + memcpy(new_skb->data, (*skb)->data, clen); + + ionic_rx_recycle(q, desc_info, *skb); + *skb = new_skb; + + return true; +} + +static void ionic_rx_clean(struct ionic_queue *q, struct ionic_desc_info *desc_info, + struct ionic_cq_info *cq_info, void *cb_arg) +{ + struct ionic_rxq_comp *comp = cq_info->cq_desc; + struct ionic_qcq *qcq = q_to_qcq(q); + struct sk_buff *skb = cb_arg; + struct ionic_rx_stats *stats; + struct net_device *netdev; + + stats = q_to_rx_stats(q); + netdev = q->lif->netdev; + + if (comp->status) { + ionic_rx_recycle(q, desc_info, skb); + return; + } + + if (unlikely(test_bit(IONIC_LIF_QUEUE_RESET, q->lif->state))) { + /* no packet processing while resetting */ + ionic_rx_recycle(q, desc_info, skb); + return; + } + + stats->pkts++; + stats->bytes += le16_to_cpu(comp->len); + + ionic_rx_copybreak(q, desc_info, cq_info, &skb); + + skb_put(skb, le16_to_cpu(comp->len)); + skb->protocol = eth_type_trans(skb, netdev); + + skb_record_rx_queue(skb, q->index); + + if (netdev->features & NETIF_F_RXHASH) { + switch (comp->pkt_type_color & IONIC_RXQ_COMP_PKT_TYPE_MASK) { + case IONIC_PKT_TYPE_IPV4: + case IONIC_PKT_TYPE_IPV6: + skb_set_hash(skb, le32_to_cpu(comp->rss_hash), + PKT_HASH_TYPE_L3); + break; + case IONIC_PKT_TYPE_IPV4_TCP: + case IONIC_PKT_TYPE_IPV6_TCP: + case IONIC_PKT_TYPE_IPV4_UDP: + case IONIC_PKT_TYPE_IPV6_UDP: + skb_set_hash(skb, le32_to_cpu(comp->rss_hash), + PKT_HASH_TYPE_L4); + break; + } + } + + if (netdev->features & NETIF_F_RXCSUM) { + if (comp->csum_flags & IONIC_RXQ_COMP_CSUM_F_CALC) { + skb->ip_summed = CHECKSUM_COMPLETE; + skb->csum = (__wsum)le16_to_cpu(comp->csum); + stats->csum_complete++; + } + } else { + stats->csum_none++; + } + + if ((comp->csum_flags & IONIC_RXQ_COMP_CSUM_F_TCP_BAD) || + (comp->csum_flags & IONIC_RXQ_COMP_CSUM_F_UDP_BAD) || + (comp->csum_flags & IONIC_RXQ_COMP_CSUM_F_IP_BAD)) + stats->csum_error++; + + if (netdev->features & NETIF_F_HW_VLAN_CTAG_RX) { + if (comp->csum_flags & IONIC_RXQ_COMP_CSUM_F_VLAN) + __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), + le16_to_cpu(comp->vlan_tci)); + } + + napi_gro_receive(&qcq->napi, skb); +} + +static bool ionic_rx_service(struct ionic_cq *cq, struct ionic_cq_info *cq_info) +{ + struct ionic_rxq_comp *comp = cq_info->cq_desc; + struct ionic_queue *q = cq->bound_q; + struct ionic_desc_info *desc_info; + + if (!color_match(comp->pkt_type_color, cq->done_color)) + return false; + + /* check for empty queue */ + if (q->tail->index == q->head->index) + return false; + + desc_info = q->tail; + if (desc_info->index != le16_to_cpu(comp->comp_index)) + return false; + + q->tail = desc_info->next; + + /* clean the related q entry, only one per qc completion */ + ionic_rx_clean(q, desc_info, cq_info, desc_info->cb_arg); + + desc_info->cb = NULL; + desc_info->cb_arg = NULL; + + return true; +} + +static u32 ionic_rx_walk_cq(struct ionic_cq *rxcq, u32 limit) +{ + u32 work_done = 0; + + while (ionic_rx_service(rxcq, rxcq->tail)) { + if (rxcq->tail->last) + rxcq->done_color = !rxcq->done_color; + rxcq->tail = rxcq->tail->next; + DEBUG_STATS_CQE_CNT(rxcq); + + if (++work_done >= limit) + break; + } + + return work_done; +} + +void ionic_rx_flush(struct ionic_cq *cq) +{ + struct ionic_dev *idev = &cq->lif->ionic->idev; + u32 work_done; + + work_done = ionic_rx_walk_cq(cq, cq->num_descs); + + if (work_done) + ionic_intr_credits(idev->intr_ctrl, cq->bound_intr->index, + work_done, IONIC_INTR_CRED_RESET_COALESCE); +} + +static struct sk_buff *ionic_rx_skb_alloc(struct ionic_queue *q, unsigned int len, + dma_addr_t *dma_addr) +{ + struct ionic_lif *lif = q->lif; + struct ionic_rx_stats *stats; + struct net_device *netdev; + struct sk_buff *skb; + struct device *dev; + + netdev = lif->netdev; + dev = lif->ionic->dev; + stats = q_to_rx_stats(q); + skb = netdev_alloc_skb_ip_align(netdev, len); + if (!skb) { + net_warn_ratelimited("%s: SKB alloc failed on %s!\n", + netdev->name, q->name); + stats->alloc_err++; + return NULL; + } + + *dma_addr = dma_map_single(dev, skb->data, len, DMA_FROM_DEVICE); + if (dma_mapping_error(dev, *dma_addr)) { + dev_kfree_skb(skb); + net_warn_ratelimited("%s: DMA single map failed on %s!\n", + netdev->name, q->name); + stats->dma_map_err++; + return NULL; + } + + return skb; +} + +#define IONIC_RX_RING_DOORBELL_STRIDE ((1 << 2) - 1) + +void ionic_rx_fill(struct ionic_queue *q) +{ + struct net_device *netdev = q->lif->netdev; + struct ionic_rxq_desc *desc; + struct sk_buff *skb; + dma_addr_t dma_addr; + bool ring_doorbell; + unsigned int len; + unsigned int i; + + len = netdev->mtu + ETH_HLEN; + + for (i = ionic_q_space_avail(q); i; i--) { + skb = ionic_rx_skb_alloc(q, len, &dma_addr); + if (!skb) + return; + + desc = q->head->desc; + desc->addr = cpu_to_le64(dma_addr); + desc->len = cpu_to_le16(len); + desc->opcode = IONIC_RXQ_DESC_OPCODE_SIMPLE; + + ring_doorbell = ((q->head->index + 1) & + IONIC_RX_RING_DOORBELL_STRIDE) == 0; + + ionic_rxq_post(q, ring_doorbell, ionic_rx_clean, skb); + } +} + +static void ionic_rx_fill_cb(void *arg) +{ + ionic_rx_fill(arg); +} + +void ionic_rx_empty(struct ionic_queue *q) +{ + struct device *dev = q->lif->ionic->dev; + struct ionic_desc_info *cur; + struct ionic_rxq_desc *desc; + + for (cur = q->tail; cur != q->head; cur = cur->next) { + desc = cur->desc; + dma_unmap_single(dev, le64_to_cpu(desc->addr), + le16_to_cpu(desc->len), DMA_FROM_DEVICE); + dev_kfree_skb(cur->cb_arg); + cur->cb_arg = NULL; + } +} + +int ionic_rx_napi(struct napi_struct *napi, int budget) +{ + struct ionic_qcq *qcq = napi_to_qcq(napi); + struct ionic_cq *rxcq = napi_to_cq(napi); + unsigned int qi = rxcq->bound_q->index; + struct ionic_dev *idev; + struct ionic_lif *lif; + struct ionic_cq *txcq; + u32 work_done = 0; + u32 flags = 0; + + lif = rxcq->bound_q->lif; + idev = &lif->ionic->idev; + txcq = &lif->txqcqs[qi].qcq->cq; + + ionic_tx_flush(txcq); + + work_done = ionic_rx_walk_cq(rxcq, budget); + + if (work_done) + ionic_rx_fill_cb(rxcq->bound_q); + + if (work_done < budget && napi_complete_done(napi, work_done)) { + flags |= IONIC_INTR_CRED_UNMASK; + DEBUG_STATS_INTR_REARM(rxcq->bound_intr); + } + + if (work_done || flags) { + flags |= IONIC_INTR_CRED_RESET_COALESCE; + ionic_intr_credits(idev->intr_ctrl, rxcq->bound_intr->index, + work_done, flags); + } + + DEBUG_STATS_NAPI_POLL(qcq, work_done); + + return work_done; +} + +static dma_addr_t ionic_tx_map_single(struct ionic_queue *q, void *data, size_t len) +{ + struct ionic_tx_stats *stats = q_to_tx_stats(q); + struct device *dev = q->lif->ionic->dev; + dma_addr_t dma_addr; + + dma_addr = dma_map_single(dev, data, len, DMA_TO_DEVICE); + if (dma_mapping_error(dev, dma_addr)) { + net_warn_ratelimited("%s: DMA single map failed on %s!\n", + q->lif->netdev->name, q->name); + stats->dma_map_err++; + return 0; + } + return dma_addr; +} + +static dma_addr_t ionic_tx_map_frag(struct ionic_queue *q, const skb_frag_t *frag, + size_t offset, size_t len) +{ + struct ionic_tx_stats *stats = q_to_tx_stats(q); + struct device *dev = q->lif->ionic->dev; + dma_addr_t dma_addr; + + dma_addr = skb_frag_dma_map(dev, frag, offset, len, DMA_TO_DEVICE); + if (dma_mapping_error(dev, dma_addr)) { + net_warn_ratelimited("%s: DMA frag map failed on %s!\n", + q->lif->netdev->name, q->name); + stats->dma_map_err++; + } + return dma_addr; +} + +static void ionic_tx_clean(struct ionic_queue *q, struct ionic_desc_info *desc_info, + struct ionic_cq_info *cq_info, void *cb_arg) +{ + struct ionic_txq_sg_desc *sg_desc = desc_info->sg_desc; + struct ionic_txq_sg_elem *elem = sg_desc->elems; + struct ionic_tx_stats *stats = q_to_tx_stats(q); + struct ionic_txq_desc *desc = desc_info->desc; + struct device *dev = q->lif->ionic->dev; + u8 opcode, flags, nsge; + u16 queue_index; + unsigned int i; + u64 addr; + + decode_txq_desc_cmd(le64_to_cpu(desc->cmd), + &opcode, &flags, &nsge, &addr); + + /* use unmap_single only if either this is not TSO, + * or this is first descriptor of a TSO + */ + if (opcode != IONIC_TXQ_DESC_OPCODE_TSO || + flags & IONIC_TXQ_DESC_FLAG_TSO_SOT) + dma_unmap_single(dev, (dma_addr_t)addr, + le16_to_cpu(desc->len), DMA_TO_DEVICE); + else + dma_unmap_page(dev, (dma_addr_t)addr, + le16_to_cpu(desc->len), DMA_TO_DEVICE); + + for (i = 0; i < nsge; i++, elem++) + dma_unmap_page(dev, (dma_addr_t)le64_to_cpu(elem->addr), + le16_to_cpu(elem->len), DMA_TO_DEVICE); + + if (cb_arg) { + struct sk_buff *skb = cb_arg; + u32 len = skb->len; + + queue_index = skb_get_queue_mapping(skb); + if (unlikely(__netif_subqueue_stopped(q->lif->netdev, + queue_index))) { + netif_wake_subqueue(q->lif->netdev, queue_index); + q->wake++; + } + dev_kfree_skb_any(skb); + stats->clean++; + netdev_tx_completed_queue(q_to_ndq(q), 1, len); + } +} + +void ionic_tx_flush(struct ionic_cq *cq) +{ + struct ionic_txq_comp *comp = cq->tail->cq_desc; + struct ionic_dev *idev = &cq->lif->ionic->idev; + struct ionic_queue *q = cq->bound_q; + struct ionic_desc_info *desc_info; + unsigned int work_done = 0; + + /* walk the completed cq entries */ + while (work_done < cq->num_descs && + color_match(comp->color, cq->done_color)) { + + /* clean the related q entries, there could be + * several q entries completed for each cq completion + */ + do { + desc_info = q->tail; + q->tail = desc_info->next; + ionic_tx_clean(q, desc_info, cq->tail, + desc_info->cb_arg); + desc_info->cb = NULL; + desc_info->cb_arg = NULL; + } while (desc_info->index != le16_to_cpu(comp->comp_index)); + + if (cq->tail->last) + cq->done_color = !cq->done_color; + + cq->tail = cq->tail->next; + comp = cq->tail->cq_desc; + DEBUG_STATS_CQE_CNT(cq); + + work_done++; + } + + if (work_done) + ionic_intr_credits(idev->intr_ctrl, cq->bound_intr->index, + work_done, 0); +} + +static int ionic_tx_tcp_inner_pseudo_csum(struct sk_buff *skb) +{ + int err; + + err = skb_cow_head(skb, 0); + if (err) + return err; + + if (skb->protocol == cpu_to_be16(ETH_P_IP)) { + inner_ip_hdr(skb)->check = 0; + inner_tcp_hdr(skb)->check = + ~csum_tcpudp_magic(inner_ip_hdr(skb)->saddr, + inner_ip_hdr(skb)->daddr, + 0, IPPROTO_TCP, 0); + } else if (skb->protocol == cpu_to_be16(ETH_P_IPV6)) { + inner_tcp_hdr(skb)->check = + ~csum_ipv6_magic(&inner_ipv6_hdr(skb)->saddr, + &inner_ipv6_hdr(skb)->daddr, + 0, IPPROTO_TCP, 0); + } + + return 0; +} + +static int ionic_tx_tcp_pseudo_csum(struct sk_buff *skb) +{ + int err; + + err = skb_cow_head(skb, 0); + if (err) + return err; + + if (skb->protocol == cpu_to_be16(ETH_P_IP)) { + ip_hdr(skb)->check = 0; + tcp_hdr(skb)->check = + ~csum_tcpudp_magic(ip_hdr(skb)->saddr, + ip_hdr(skb)->daddr, + 0, IPPROTO_TCP, 0); + } else if (skb->protocol == cpu_to_be16(ETH_P_IPV6)) { + tcp_hdr(skb)->check = + ~csum_ipv6_magic(&ipv6_hdr(skb)->saddr, + &ipv6_hdr(skb)->daddr, + 0, IPPROTO_TCP, 0); + } + + return 0; +} + +static void ionic_tx_tso_post(struct ionic_queue *q, struct ionic_txq_desc *desc, + struct sk_buff *skb, + dma_addr_t addr, u8 nsge, u16 len, + unsigned int hdrlen, unsigned int mss, + bool outer_csum, + u16 vlan_tci, bool has_vlan, + bool start, bool done) +{ + u8 flags = 0; + u64 cmd; + + flags |= has_vlan ? IONIC_TXQ_DESC_FLAG_VLAN : 0; + flags |= outer_csum ? IONIC_TXQ_DESC_FLAG_ENCAP : 0; + flags |= start ? IONIC_TXQ_DESC_FLAG_TSO_SOT : 0; + flags |= done ? IONIC_TXQ_DESC_FLAG_TSO_EOT : 0; + + cmd = encode_txq_desc_cmd(IONIC_TXQ_DESC_OPCODE_TSO, flags, nsge, addr); + desc->cmd = cpu_to_le64(cmd); + desc->len = cpu_to_le16(len); + desc->vlan_tci = cpu_to_le16(vlan_tci); + desc->hdr_len = cpu_to_le16(hdrlen); + desc->mss = cpu_to_le16(mss); + + if (done) { + skb_tx_timestamp(skb); + netdev_tx_sent_queue(q_to_ndq(q), skb->len); + ionic_txq_post(q, !netdev_xmit_more(), ionic_tx_clean, skb); + } else { + ionic_txq_post(q, false, ionic_tx_clean, NULL); + } +} + +static struct ionic_txq_desc *ionic_tx_tso_next(struct ionic_queue *q, + struct ionic_txq_sg_elem **elem) +{ + struct ionic_txq_sg_desc *sg_desc = q->head->sg_desc; + struct ionic_txq_desc *desc = q->head->desc; + + *elem = sg_desc->elems; + return desc; +} + +static int ionic_tx_tso(struct ionic_queue *q, struct sk_buff *skb) +{ + struct ionic_tx_stats *stats = q_to_tx_stats(q); + struct ionic_desc_info *abort = q->head; + struct device *dev = q->lif->ionic->dev; + struct ionic_desc_info *rewind = abort; + struct ionic_txq_sg_elem *elem; + struct ionic_txq_desc *desc; + unsigned int frag_left = 0; + unsigned int offset = 0; + unsigned int len_left; + dma_addr_t desc_addr; + unsigned int hdrlen; + unsigned int nfrags; + unsigned int seglen; + u64 total_bytes = 0; + u64 total_pkts = 0; + unsigned int left; + unsigned int len; + unsigned int mss; + skb_frag_t *frag; + bool start, done; + bool outer_csum; + bool has_vlan; + u16 desc_len; + u8 desc_nsge; + u16 vlan_tci; + bool encap; + int err; + + mss = skb_shinfo(skb)->gso_size; + nfrags = skb_shinfo(skb)->nr_frags; + len_left = skb->len - skb_headlen(skb); + outer_csum = (skb_shinfo(skb)->gso_type & SKB_GSO_GRE_CSUM) || + (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_TUNNEL_CSUM); + has_vlan = !!skb_vlan_tag_present(skb); + vlan_tci = skb_vlan_tag_get(skb); + encap = skb->encapsulation; + + /* Preload inner-most TCP csum field with IP pseudo hdr + * calculated with IP length set to zero. HW will later + * add in length to each TCP segment resulting from the TSO. + */ + + if (encap) + err = ionic_tx_tcp_inner_pseudo_csum(skb); + else + err = ionic_tx_tcp_pseudo_csum(skb); + if (err) + return err; + + if (encap) + hdrlen = skb_inner_transport_header(skb) - skb->data + + inner_tcp_hdrlen(skb); + else + hdrlen = skb_transport_offset(skb) + tcp_hdrlen(skb); + + seglen = hdrlen + mss; + left = skb_headlen(skb); + + desc = ionic_tx_tso_next(q, &elem); + start = true; + + /* Chop skb->data up into desc segments */ + + while (left > 0) { + len = min(seglen, left); + frag_left = seglen - len; + desc_addr = ionic_tx_map_single(q, skb->data + offset, len); + if (dma_mapping_error(dev, desc_addr)) + goto err_out_abort; + desc_len = len; + desc_nsge = 0; + left -= len; + offset += len; + if (nfrags > 0 && frag_left > 0) + continue; + done = (nfrags == 0 && left == 0); + ionic_tx_tso_post(q, desc, skb, + desc_addr, desc_nsge, desc_len, + hdrlen, mss, + outer_csum, + vlan_tci, has_vlan, + start, done); + total_pkts++; + total_bytes += start ? len : len + hdrlen; + desc = ionic_tx_tso_next(q, &elem); + start = false; + seglen = mss; + } + + /* Chop skb frags into desc segments */ + + for (frag = skb_shinfo(skb)->frags; len_left; frag++) { + offset = 0; + left = skb_frag_size(frag); + len_left -= left; + nfrags--; + stats->frags++; + + while (left > 0) { + if (frag_left > 0) { + len = min(frag_left, left); + frag_left -= len; + elem->addr = + cpu_to_le64(ionic_tx_map_frag(q, frag, + offset, len)); + if (dma_mapping_error(dev, elem->addr)) + goto err_out_abort; + elem->len = cpu_to_le16(len); + elem++; + desc_nsge++; + left -= len; + offset += len; + if (nfrags > 0 && frag_left > 0) + continue; + done = (nfrags == 0 && left == 0); + ionic_tx_tso_post(q, desc, skb, desc_addr, + desc_nsge, desc_len, + hdrlen, mss, outer_csum, + vlan_tci, has_vlan, + start, done); + total_pkts++; + total_bytes += start ? len : len + hdrlen; + desc = ionic_tx_tso_next(q, &elem); + start = false; + } else { + len = min(mss, left); + frag_left = mss - len; + desc_addr = ionic_tx_map_frag(q, frag, + offset, len); + if (dma_mapping_error(dev, desc_addr)) + goto err_out_abort; + desc_len = len; + desc_nsge = 0; + left -= len; + offset += len; + if (nfrags > 0 && frag_left > 0) + continue; + done = (nfrags == 0 && left == 0); + ionic_tx_tso_post(q, desc, skb, desc_addr, + desc_nsge, desc_len, + hdrlen, mss, outer_csum, + vlan_tci, has_vlan, + start, done); + total_pkts++; + total_bytes += start ? len : len + hdrlen; + desc = ionic_tx_tso_next(q, &elem); + start = false; + } + } + } + + stats->pkts += total_pkts; + stats->bytes += total_bytes; + stats->tso++; + + return 0; + +err_out_abort: + while (rewind->desc != q->head->desc) { + ionic_tx_clean(q, rewind, NULL, NULL); + rewind = rewind->next; + } + q->head = abort; + + return -ENOMEM; +} + +static int ionic_tx_calc_csum(struct ionic_queue *q, struct sk_buff *skb) +{ + struct ionic_tx_stats *stats = q_to_tx_stats(q); + struct ionic_txq_desc *desc = q->head->desc; + struct device *dev = q->lif->ionic->dev; + dma_addr_t dma_addr; + bool has_vlan; + u8 flags = 0; + bool encap; + u64 cmd; + + has_vlan = !!skb_vlan_tag_present(skb); + encap = skb->encapsulation; + + dma_addr = ionic_tx_map_single(q, skb->data, skb_headlen(skb)); + if (dma_mapping_error(dev, dma_addr)) + return -ENOMEM; + + flags |= has_vlan ? IONIC_TXQ_DESC_FLAG_VLAN : 0; + flags |= encap ? IONIC_TXQ_DESC_FLAG_ENCAP : 0; + + cmd = encode_txq_desc_cmd(IONIC_TXQ_DESC_OPCODE_CSUM_PARTIAL, + flags, skb_shinfo(skb)->nr_frags, dma_addr); + desc->cmd = cpu_to_le64(cmd); + desc->len = cpu_to_le16(skb_headlen(skb)); + desc->vlan_tci = cpu_to_le16(skb_vlan_tag_get(skb)); + desc->csum_start = cpu_to_le16(skb_checksum_start_offset(skb)); + desc->csum_offset = cpu_to_le16(skb->csum_offset); + + if (skb->csum_not_inet) + stats->crc32_csum++; + else + stats->csum++; + + return 0; +} + +static int ionic_tx_calc_no_csum(struct ionic_queue *q, struct sk_buff *skb) +{ + struct ionic_tx_stats *stats = q_to_tx_stats(q); + struct ionic_txq_desc *desc = q->head->desc; + struct device *dev = q->lif->ionic->dev; + dma_addr_t dma_addr; + bool has_vlan; + u8 flags = 0; + bool encap; + u64 cmd; + + has_vlan = !!skb_vlan_tag_present(skb); + encap = skb->encapsulation; + + dma_addr = ionic_tx_map_single(q, skb->data, skb_headlen(skb)); + if (dma_mapping_error(dev, dma_addr)) + return -ENOMEM; + + flags |= has_vlan ? IONIC_TXQ_DESC_FLAG_VLAN : 0; + flags |= encap ? IONIC_TXQ_DESC_FLAG_ENCAP : 0; + + cmd = encode_txq_desc_cmd(IONIC_TXQ_DESC_OPCODE_CSUM_NONE, + flags, skb_shinfo(skb)->nr_frags, dma_addr); + desc->cmd = cpu_to_le64(cmd); + desc->len = cpu_to_le16(skb_headlen(skb)); + desc->vlan_tci = cpu_to_le16(skb_vlan_tag_get(skb)); + + stats->no_csum++; + + return 0; +} + +static int ionic_tx_skb_frags(struct ionic_queue *q, struct sk_buff *skb) +{ + struct ionic_txq_sg_desc *sg_desc = q->head->sg_desc; + unsigned int len_left = skb->len - skb_headlen(skb); + struct ionic_txq_sg_elem *elem = sg_desc->elems; + struct ionic_tx_stats *stats = q_to_tx_stats(q); + struct device *dev = q->lif->ionic->dev; + dma_addr_t dma_addr; + skb_frag_t *frag; + u16 len; + + for (frag = skb_shinfo(skb)->frags; len_left; frag++, elem++) { + len = skb_frag_size(frag); + elem->len = cpu_to_le16(len); + dma_addr = ionic_tx_map_frag(q, frag, 0, len); + if (dma_mapping_error(dev, dma_addr)) + return -ENOMEM; + elem->addr = cpu_to_le64(dma_addr); + len_left -= len; + stats->frags++; + } + + return 0; +} + +static int ionic_tx(struct ionic_queue *q, struct sk_buff *skb) +{ + struct ionic_tx_stats *stats = q_to_tx_stats(q); + int err; + + /* set up the initial descriptor */ + if (skb->ip_summed == CHECKSUM_PARTIAL) + err = ionic_tx_calc_csum(q, skb); + else + err = ionic_tx_calc_no_csum(q, skb); + if (err) + return err; + + /* add frags */ + err = ionic_tx_skb_frags(q, skb); + if (err) + return err; + + skb_tx_timestamp(skb); + stats->pkts++; + stats->bytes += skb->len; + + netdev_tx_sent_queue(q_to_ndq(q), skb->len); + ionic_txq_post(q, !netdev_xmit_more(), ionic_tx_clean, skb); + + return 0; +} + +static int ionic_tx_descs_needed(struct ionic_queue *q, struct sk_buff *skb) +{ + struct ionic_tx_stats *stats = q_to_tx_stats(q); + int err; + + /* If TSO, need roundup(skb->len/mss) descs */ + if (skb_is_gso(skb)) + return (skb->len / skb_shinfo(skb)->gso_size) + 1; + + /* If non-TSO, just need 1 desc and nr_frags sg elems */ + if (skb_shinfo(skb)->nr_frags <= IONIC_TX_MAX_SG_ELEMS) + return 1; + + /* Too many frags, so linearize */ + err = skb_linearize(skb); + if (err) + return err; + + stats->linearize++; + + /* Need 1 desc and zero sg elems */ + return 1; +} + +static int ionic_maybe_stop_tx(struct ionic_queue *q, int ndescs) +{ + int stopped = 0; + + if (unlikely(!ionic_q_has_space(q, ndescs))) { + netif_stop_subqueue(q->lif->netdev, q->index); + q->stop++; + stopped = 1; + + /* Might race with ionic_tx_clean, check again */ + smp_rmb(); + if (ionic_q_has_space(q, ndescs)) { + netif_wake_subqueue(q->lif->netdev, q->index); + stopped = 0; + } + } + + return stopped; +} + +netdev_tx_t ionic_start_xmit(struct sk_buff *skb, struct net_device *netdev) +{ + u16 queue_index = skb_get_queue_mapping(skb); + struct ionic_lif *lif = netdev_priv(netdev); + struct ionic_queue *q; + int ndescs; + int err; + + if (unlikely(!test_bit(IONIC_LIF_UP, lif->state))) { + dev_kfree_skb(skb); + return NETDEV_TX_OK; + } + + if (unlikely(!lif_to_txqcq(lif, queue_index))) + queue_index = 0; + q = lif_to_txq(lif, queue_index); + + ndescs = ionic_tx_descs_needed(q, skb); + if (ndescs < 0) + goto err_out_drop; + + if (unlikely(ionic_maybe_stop_tx(q, ndescs))) + return NETDEV_TX_BUSY; + + if (skb_is_gso(skb)) + err = ionic_tx_tso(q, skb); + else + err = ionic_tx(q, skb); + + if (err) + goto err_out_drop; + + /* Stop the queue if there aren't descriptors for the next packet. + * Since our SG lists per descriptor take care of most of the possible + * fragmentation, we don't need to have many descriptors available. + */ + ionic_maybe_stop_tx(q, 4); + + return NETDEV_TX_OK; + +err_out_drop: + q->stop++; + q->drop++; + dev_kfree_skb(skb); + return NETDEV_TX_OK; +} |