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Diffstat (limited to '')
| -rw-r--r-- | drivers/infiniband/hw/hfi1/vnic_sdma.c | 324 |
1 files changed, 324 insertions, 0 deletions
diff --git a/drivers/infiniband/hw/hfi1/vnic_sdma.c b/drivers/infiniband/hw/hfi1/vnic_sdma.c new file mode 100644 index 000000000..ab8bcdf10 --- /dev/null +++ b/drivers/infiniband/hw/hfi1/vnic_sdma.c @@ -0,0 +1,324 @@ +/* + * Copyright(c) 2017 - 2018 Intel Corporation. + * + * This file is provided under a dual BSD/GPLv2 license. When using or + * redistributing this file, you may do so under either license. + * + * GPL LICENSE SUMMARY + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of version 2 of the GNU General Public License as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that 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. + * + * BSD LICENSE + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * - Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * - Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * - Neither the name of Intel Corporation nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + */ + +/* + * This file contains HFI1 support for VNIC SDMA functionality + */ + +#include "sdma.h" +#include "vnic.h" + +#define HFI1_VNIC_SDMA_Q_ACTIVE BIT(0) +#define HFI1_VNIC_SDMA_Q_DEFERRED BIT(1) + +#define HFI1_VNIC_TXREQ_NAME_LEN 32 +#define HFI1_VNIC_SDMA_DESC_WTRMRK 64 + +/* + * struct vnic_txreq - VNIC transmit descriptor + * @txreq: sdma transmit request + * @sdma: vnic sdma pointer + * @skb: skb to send + * @pad: pad buffer + * @plen: pad length + * @pbc_val: pbc value + */ +struct vnic_txreq { + struct sdma_txreq txreq; + struct hfi1_vnic_sdma *sdma; + + struct sk_buff *skb; + unsigned char pad[HFI1_VNIC_MAX_PAD]; + u16 plen; + __le64 pbc_val; +}; + +static void vnic_sdma_complete(struct sdma_txreq *txreq, + int status) +{ + struct vnic_txreq *tx = container_of(txreq, struct vnic_txreq, txreq); + struct hfi1_vnic_sdma *vnic_sdma = tx->sdma; + + sdma_txclean(vnic_sdma->dd, txreq); + dev_kfree_skb_any(tx->skb); + kmem_cache_free(vnic_sdma->dd->vnic.txreq_cache, tx); +} + +static noinline int build_vnic_ulp_payload(struct sdma_engine *sde, + struct vnic_txreq *tx) +{ + int i, ret = 0; + + ret = sdma_txadd_kvaddr( + sde->dd, + &tx->txreq, + tx->skb->data, + skb_headlen(tx->skb)); + if (unlikely(ret)) + goto bail_txadd; + + for (i = 0; i < skb_shinfo(tx->skb)->nr_frags; i++) { + skb_frag_t *frag = &skb_shinfo(tx->skb)->frags[i]; + + /* combine physically continuous fragments later? */ + ret = sdma_txadd_page(sde->dd, + &tx->txreq, + skb_frag_page(frag), + skb_frag_off(frag), + skb_frag_size(frag), + NULL, NULL, NULL); + if (unlikely(ret)) + goto bail_txadd; + } + + if (tx->plen) + ret = sdma_txadd_kvaddr(sde->dd, &tx->txreq, + tx->pad + HFI1_VNIC_MAX_PAD - tx->plen, + tx->plen); + +bail_txadd: + return ret; +} + +static int build_vnic_tx_desc(struct sdma_engine *sde, + struct vnic_txreq *tx, + u64 pbc) +{ + int ret = 0; + u16 hdrbytes = 2 << 2; /* PBC */ + + ret = sdma_txinit_ahg( + &tx->txreq, + 0, + hdrbytes + tx->skb->len + tx->plen, + 0, + 0, + NULL, + 0, + vnic_sdma_complete); + if (unlikely(ret)) + goto bail_txadd; + + /* add pbc */ + tx->pbc_val = cpu_to_le64(pbc); + ret = sdma_txadd_kvaddr( + sde->dd, + &tx->txreq, + &tx->pbc_val, + hdrbytes); + if (unlikely(ret)) + goto bail_txadd; + + /* add the ulp payload */ + ret = build_vnic_ulp_payload(sde, tx); +bail_txadd: + return ret; +} + +/* setup the last plen bypes of pad */ +static inline void hfi1_vnic_update_pad(unsigned char *pad, u8 plen) +{ + pad[HFI1_VNIC_MAX_PAD - 1] = plen - OPA_VNIC_ICRC_TAIL_LEN; +} + +int hfi1_vnic_send_dma(struct hfi1_devdata *dd, u8 q_idx, + struct hfi1_vnic_vport_info *vinfo, + struct sk_buff *skb, u64 pbc, u8 plen) +{ + struct hfi1_vnic_sdma *vnic_sdma = &vinfo->sdma[q_idx]; + struct sdma_engine *sde = vnic_sdma->sde; + struct vnic_txreq *tx; + int ret = -ECOMM; + + if (unlikely(READ_ONCE(vnic_sdma->state) != HFI1_VNIC_SDMA_Q_ACTIVE)) + goto tx_err; + + if (unlikely(!sde || !sdma_running(sde))) + goto tx_err; + + tx = kmem_cache_alloc(dd->vnic.txreq_cache, GFP_ATOMIC); + if (unlikely(!tx)) { + ret = -ENOMEM; + goto tx_err; + } + + tx->sdma = vnic_sdma; + tx->skb = skb; + hfi1_vnic_update_pad(tx->pad, plen); + tx->plen = plen; + ret = build_vnic_tx_desc(sde, tx, pbc); + if (unlikely(ret)) + goto free_desc; + + ret = sdma_send_txreq(sde, iowait_get_ib_work(&vnic_sdma->wait), + &tx->txreq, vnic_sdma->pkts_sent); + /* When -ECOMM, sdma callback will be called with ABORT status */ + if (unlikely(ret && unlikely(ret != -ECOMM))) + goto free_desc; + + if (!ret) { + vnic_sdma->pkts_sent = true; + iowait_starve_clear(vnic_sdma->pkts_sent, &vnic_sdma->wait); + } + return ret; + +free_desc: + sdma_txclean(dd, &tx->txreq); + kmem_cache_free(dd->vnic.txreq_cache, tx); +tx_err: + if (ret != -EBUSY) + dev_kfree_skb_any(skb); + else + vnic_sdma->pkts_sent = false; + return ret; +} + +/* + * hfi1_vnic_sdma_sleep - vnic sdma sleep function + * + * This function gets called from sdma_send_txreq() when there are not enough + * sdma descriptors available to send the packet. It adds Tx queue's wait + * structure to sdma engine's dmawait list to be woken up when descriptors + * become available. + */ +static int hfi1_vnic_sdma_sleep(struct sdma_engine *sde, + struct iowait_work *wait, + struct sdma_txreq *txreq, + uint seq, + bool pkts_sent) +{ + struct hfi1_vnic_sdma *vnic_sdma = + container_of(wait->iow, struct hfi1_vnic_sdma, wait); + + write_seqlock(&sde->waitlock); + if (sdma_progress(sde, seq, txreq)) { + write_sequnlock(&sde->waitlock); + return -EAGAIN; + } + + vnic_sdma->state = HFI1_VNIC_SDMA_Q_DEFERRED; + if (list_empty(&vnic_sdma->wait.list)) { + iowait_get_priority(wait->iow); + iowait_queue(pkts_sent, wait->iow, &sde->dmawait); + } + write_sequnlock(&sde->waitlock); + return -EBUSY; +} + +/* + * hfi1_vnic_sdma_wakeup - vnic sdma wakeup function + * + * This function gets called when SDMA descriptors becomes available and Tx + * queue's wait structure was previously added to sdma engine's dmawait list. + * It notifies the upper driver about Tx queue wakeup. + */ +static void hfi1_vnic_sdma_wakeup(struct iowait *wait, int reason) +{ + struct hfi1_vnic_sdma *vnic_sdma = + container_of(wait, struct hfi1_vnic_sdma, wait); + struct hfi1_vnic_vport_info *vinfo = vnic_sdma->vinfo; + + vnic_sdma->state = HFI1_VNIC_SDMA_Q_ACTIVE; + if (__netif_subqueue_stopped(vinfo->netdev, vnic_sdma->q_idx)) + netif_wake_subqueue(vinfo->netdev, vnic_sdma->q_idx); +}; + +inline bool hfi1_vnic_sdma_write_avail(struct hfi1_vnic_vport_info *vinfo, + u8 q_idx) +{ + struct hfi1_vnic_sdma *vnic_sdma = &vinfo->sdma[q_idx]; + + return (READ_ONCE(vnic_sdma->state) == HFI1_VNIC_SDMA_Q_ACTIVE); +} + +void hfi1_vnic_sdma_init(struct hfi1_vnic_vport_info *vinfo) +{ + int i; + + for (i = 0; i < vinfo->num_tx_q; i++) { + struct hfi1_vnic_sdma *vnic_sdma = &vinfo->sdma[i]; + + iowait_init(&vnic_sdma->wait, 0, NULL, NULL, + hfi1_vnic_sdma_sleep, + hfi1_vnic_sdma_wakeup, NULL, NULL); + vnic_sdma->sde = &vinfo->dd->per_sdma[i]; + vnic_sdma->dd = vinfo->dd; + vnic_sdma->vinfo = vinfo; + vnic_sdma->q_idx = i; + vnic_sdma->state = HFI1_VNIC_SDMA_Q_ACTIVE; + + /* Add a free descriptor watermark for wakeups */ + if (vnic_sdma->sde->descq_cnt > HFI1_VNIC_SDMA_DESC_WTRMRK) { + struct iowait_work *work; + + INIT_LIST_HEAD(&vnic_sdma->stx.list); + vnic_sdma->stx.num_desc = HFI1_VNIC_SDMA_DESC_WTRMRK; + work = iowait_get_ib_work(&vnic_sdma->wait); + list_add_tail(&vnic_sdma->stx.list, &work->tx_head); + } + } +} + +int hfi1_vnic_txreq_init(struct hfi1_devdata *dd) +{ + char buf[HFI1_VNIC_TXREQ_NAME_LEN]; + + snprintf(buf, sizeof(buf), "hfi1_%u_vnic_txreq_cache", dd->unit); + dd->vnic.txreq_cache = kmem_cache_create(buf, + sizeof(struct vnic_txreq), + 0, SLAB_HWCACHE_ALIGN, + NULL); + if (!dd->vnic.txreq_cache) + return -ENOMEM; + return 0; +} + +void hfi1_vnic_txreq_deinit(struct hfi1_devdata *dd) +{ + kmem_cache_destroy(dd->vnic.txreq_cache); + dd->vnic.txreq_cache = NULL; +} |