The Design and Implementation of the FreeBSD Operating System, Second Edition
Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)


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FreeBSD/Linux Kernel Cross Reference
sys/dev/sfxge/sfxge_tx.c

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    1 /*-
    2  * Copyright (c) 2010-2016 Solarflare Communications Inc.
    3  * All rights reserved.
    4  *
    5  * This software was developed in part by Philip Paeps under contract for
    6  * Solarflare Communications, Inc.
    7  *
    8  * Redistribution and use in source and binary forms, with or without
    9  * modification, are permitted provided that the following conditions are met:
   10  *
   11  * 1. Redistributions of source code must retain the above copyright notice,
   12  *    this list of conditions and the following disclaimer.
   13  * 2. Redistributions in binary form must reproduce the above copyright notice,
   14  *    this list of conditions and the following disclaimer in the documentation
   15  *    and/or other materials provided with the distribution.
   16  *
   17  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
   18  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
   19  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
   20  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
   21  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
   22  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
   23  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
   24  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
   25  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
   26  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
   27  * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   28  *
   29  * The views and conclusions contained in the software and documentation are
   30  * those of the authors and should not be interpreted as representing official
   31  * policies, either expressed or implied, of the FreeBSD Project.
   32  */
   33 
   34 /* Theory of operation:
   35  *
   36  * Tx queues allocation and mapping
   37  *
   38  * One Tx queue with enabled checksum offload is allocated per Rx channel
   39  * (event queue).  Also 2 Tx queues (one without checksum offload and one
   40  * with IP checksum offload only) are allocated and bound to event queue 0.
   41  * sfxge_txq_type is used as Tx queue label.
   42  *
   43  * So, event queue plus label mapping to Tx queue index is:
   44  *      if event queue index is 0, TxQ-index = TxQ-label * [0..SFXGE_TXQ_NTYPES)
   45  *      else TxQ-index = SFXGE_TXQ_NTYPES + EvQ-index - 1
   46  * See sfxge_get_txq_by_label() sfxge_ev.c
   47  */
   48 
   49 #include <sys/cdefs.h>
   50 __FBSDID("$FreeBSD: releng/11.2/sys/dev/sfxge/sfxge_tx.c 331722 2018-03-29 02:50:57Z eadler $");
   51 
   52 #include "opt_rss.h"
   53 
   54 #include <sys/param.h>
   55 #include <sys/malloc.h>
   56 #include <sys/mbuf.h>
   57 #include <sys/smp.h>
   58 #include <sys/socket.h>
   59 #include <sys/sysctl.h>
   60 #include <sys/syslog.h>
   61 #include <sys/limits.h>
   62 
   63 #include <net/bpf.h>
   64 #include <net/ethernet.h>
   65 #include <net/if.h>
   66 #include <net/if_vlan_var.h>
   67 
   68 #include <netinet/in.h>
   69 #include <netinet/ip.h>
   70 #include <netinet/ip6.h>
   71 #include <netinet/tcp.h>
   72 
   73 #ifdef RSS
   74 #include <net/rss_config.h>
   75 #endif
   76 
   77 #include "common/efx.h"
   78 
   79 #include "sfxge.h"
   80 #include "sfxge_tx.h"
   81 
   82 
   83 #define SFXGE_PARAM_TX_DPL_GET_MAX      SFXGE_PARAM(tx_dpl_get_max)
   84 static int sfxge_tx_dpl_get_max = SFXGE_TX_DPL_GET_PKT_LIMIT_DEFAULT;
   85 TUNABLE_INT(SFXGE_PARAM_TX_DPL_GET_MAX, &sfxge_tx_dpl_get_max);
   86 SYSCTL_INT(_hw_sfxge, OID_AUTO, tx_dpl_get_max, CTLFLAG_RDTUN,
   87            &sfxge_tx_dpl_get_max, 0,
   88            "Maximum number of any packets in deferred packet get-list");
   89 
   90 #define SFXGE_PARAM_TX_DPL_GET_NON_TCP_MAX \
   91         SFXGE_PARAM(tx_dpl_get_non_tcp_max)
   92 static int sfxge_tx_dpl_get_non_tcp_max =
   93         SFXGE_TX_DPL_GET_NON_TCP_PKT_LIMIT_DEFAULT;
   94 TUNABLE_INT(SFXGE_PARAM_TX_DPL_GET_NON_TCP_MAX, &sfxge_tx_dpl_get_non_tcp_max);
   95 SYSCTL_INT(_hw_sfxge, OID_AUTO, tx_dpl_get_non_tcp_max, CTLFLAG_RDTUN,
   96            &sfxge_tx_dpl_get_non_tcp_max, 0,
   97            "Maximum number of non-TCP packets in deferred packet get-list");
   98 
   99 #define SFXGE_PARAM_TX_DPL_PUT_MAX      SFXGE_PARAM(tx_dpl_put_max)
  100 static int sfxge_tx_dpl_put_max = SFXGE_TX_DPL_PUT_PKT_LIMIT_DEFAULT;
  101 TUNABLE_INT(SFXGE_PARAM_TX_DPL_PUT_MAX, &sfxge_tx_dpl_put_max);
  102 SYSCTL_INT(_hw_sfxge, OID_AUTO, tx_dpl_put_max, CTLFLAG_RDTUN,
  103            &sfxge_tx_dpl_put_max, 0,
  104            "Maximum number of any packets in deferred packet put-list");
  105 
  106 #define SFXGE_PARAM_TSO_FW_ASSISTED     SFXGE_PARAM(tso_fw_assisted)
  107 static int sfxge_tso_fw_assisted = (SFXGE_FATSOV1 | SFXGE_FATSOV2);
  108 TUNABLE_INT(SFXGE_PARAM_TSO_FW_ASSISTED, &sfxge_tso_fw_assisted);
  109 SYSCTL_INT(_hw_sfxge, OID_AUTO, tso_fw_assisted, CTLFLAG_RDTUN,
  110            &sfxge_tso_fw_assisted, 0,
  111            "Bitmask of FW-assisted TSO allowed to use if supported by NIC firmware");
  112 
  113 
  114 static const struct {
  115         const char *name;
  116         size_t offset;
  117 } sfxge_tx_stats[] = {
  118 #define SFXGE_TX_STAT(name, member) \
  119         { #name, offsetof(struct sfxge_txq, member) }
  120         SFXGE_TX_STAT(tso_bursts, tso_bursts),
  121         SFXGE_TX_STAT(tso_packets, tso_packets),
  122         SFXGE_TX_STAT(tso_long_headers, tso_long_headers),
  123         SFXGE_TX_STAT(tso_pdrop_too_many, tso_pdrop_too_many),
  124         SFXGE_TX_STAT(tso_pdrop_no_rsrc, tso_pdrop_no_rsrc),
  125         SFXGE_TX_STAT(tx_collapses, collapses),
  126         SFXGE_TX_STAT(tx_drops, drops),
  127         SFXGE_TX_STAT(tx_get_overflow, get_overflow),
  128         SFXGE_TX_STAT(tx_get_non_tcp_overflow, get_non_tcp_overflow),
  129         SFXGE_TX_STAT(tx_put_overflow, put_overflow),
  130         SFXGE_TX_STAT(tx_netdown_drops, netdown_drops),
  131 };
  132 
  133 
  134 /* Forward declarations. */
  135 static void sfxge_tx_qdpl_service(struct sfxge_txq *txq);
  136 static void sfxge_tx_qlist_post(struct sfxge_txq *txq);
  137 static void sfxge_tx_qunblock(struct sfxge_txq *txq);
  138 static int sfxge_tx_queue_tso(struct sfxge_txq *txq, struct mbuf *mbuf,
  139                               const bus_dma_segment_t *dma_seg, int n_dma_seg,
  140                               int vlan_tagged);
  141 
  142 static int
  143 sfxge_tx_maybe_insert_tag(struct sfxge_txq *txq, struct mbuf *mbuf)
  144 {
  145         uint16_t this_tag = ((mbuf->m_flags & M_VLANTAG) ?
  146                              mbuf->m_pkthdr.ether_vtag :
  147                              0);
  148 
  149         if (this_tag == txq->hw_vlan_tci)
  150                 return (0);
  151 
  152         efx_tx_qdesc_vlantci_create(txq->common,
  153                                     bswap16(this_tag),
  154                                     &txq->pend_desc[0]);
  155         txq->n_pend_desc = 1;
  156         txq->hw_vlan_tci = this_tag;
  157         return (1);
  158 }
  159 
  160 static inline void
  161 sfxge_next_stmp(struct sfxge_txq *txq, struct sfxge_tx_mapping **pstmp)
  162 {
  163         KASSERT((*pstmp)->flags == 0, ("stmp flags are not 0"));
  164         if (__predict_false(*pstmp ==
  165                             &txq->stmp[txq->ptr_mask]))
  166                 *pstmp = &txq->stmp[0];
  167         else
  168                 (*pstmp)++;
  169 }
  170 
  171 
  172 void
  173 sfxge_tx_qcomplete(struct sfxge_txq *txq, struct sfxge_evq *evq)
  174 {
  175         unsigned int completed;
  176 
  177         SFXGE_EVQ_LOCK_ASSERT_OWNED(evq);
  178 
  179         completed = txq->completed;
  180         while (completed != txq->pending) {
  181                 struct sfxge_tx_mapping *stmp;
  182                 unsigned int id;
  183 
  184                 id = completed++ & txq->ptr_mask;
  185 
  186                 stmp = &txq->stmp[id];
  187                 if (stmp->flags & TX_BUF_UNMAP) {
  188                         bus_dmamap_unload(txq->packet_dma_tag, stmp->map);
  189                         if (stmp->flags & TX_BUF_MBUF) {
  190                                 struct mbuf *m = stmp->u.mbuf;
  191                                 do
  192                                         m = m_free(m);
  193                                 while (m != NULL);
  194                         } else {
  195                                 free(stmp->u.heap_buf, M_SFXGE);
  196                         }
  197                         stmp->flags = 0;
  198                 }
  199         }
  200         txq->completed = completed;
  201 
  202         /* Check whether we need to unblock the queue. */
  203         mb();
  204         if (txq->blocked) {
  205                 unsigned int level;
  206 
  207                 level = txq->added - txq->completed;
  208                 if (level <= SFXGE_TXQ_UNBLOCK_LEVEL(txq->entries))
  209                         sfxge_tx_qunblock(txq);
  210         }
  211 }
  212 
  213 static unsigned int
  214 sfxge_is_mbuf_non_tcp(struct mbuf *mbuf)
  215 {
  216         /* Absence of TCP checksum flags does not mean that it is non-TCP
  217          * but it should be true if user wants to achieve high throughput.
  218          */
  219         return (!(mbuf->m_pkthdr.csum_flags & (CSUM_IP_TCP | CSUM_IP6_TCP)));
  220 }
  221 
  222 /*
  223  * Reorder the put list and append it to the get list.
  224  */
  225 static void
  226 sfxge_tx_qdpl_swizzle(struct sfxge_txq *txq)
  227 {
  228         struct sfxge_tx_dpl *stdp;
  229         struct mbuf *mbuf, *get_next, **get_tailp;
  230         volatile uintptr_t *putp;
  231         uintptr_t put;
  232         unsigned int count;
  233         unsigned int non_tcp_count;
  234 
  235         SFXGE_TXQ_LOCK_ASSERT_OWNED(txq);
  236 
  237         stdp = &txq->dpl;
  238 
  239         /* Acquire the put list. */
  240         putp = &stdp->std_put;
  241         put = atomic_readandclear_ptr(putp);
  242         mbuf = (void *)put;
  243 
  244         if (mbuf == NULL)
  245                 return;
  246 
  247         /* Reverse the put list. */
  248         get_tailp = &mbuf->m_nextpkt;
  249         get_next = NULL;
  250 
  251         count = 0;
  252         non_tcp_count = 0;
  253         do {
  254                 struct mbuf *put_next;
  255 
  256                 non_tcp_count += sfxge_is_mbuf_non_tcp(mbuf);
  257                 put_next = mbuf->m_nextpkt;
  258                 mbuf->m_nextpkt = get_next;
  259                 get_next = mbuf;
  260                 mbuf = put_next;
  261 
  262                 count++;
  263         } while (mbuf != NULL);
  264 
  265         if (count > stdp->std_put_hiwat)
  266                 stdp->std_put_hiwat = count;
  267 
  268         /* Append the reversed put list to the get list. */
  269         KASSERT(*get_tailp == NULL, ("*get_tailp != NULL"));
  270         *stdp->std_getp = get_next;
  271         stdp->std_getp = get_tailp;
  272         stdp->std_get_count += count;
  273         stdp->std_get_non_tcp_count += non_tcp_count;
  274 }
  275 
  276 static void
  277 sfxge_tx_qreap(struct sfxge_txq *txq)
  278 {
  279         SFXGE_TXQ_LOCK_ASSERT_OWNED(txq);
  280 
  281         txq->reaped = txq->completed;
  282 }
  283 
  284 static void
  285 sfxge_tx_qlist_post(struct sfxge_txq *txq)
  286 {
  287         unsigned int old_added;
  288         unsigned int block_level;
  289         unsigned int level;
  290         int rc;
  291 
  292         SFXGE_TXQ_LOCK_ASSERT_OWNED(txq);
  293 
  294         KASSERT(txq->n_pend_desc != 0, ("txq->n_pend_desc == 0"));
  295         KASSERT(txq->n_pend_desc <= txq->max_pkt_desc,
  296                 ("txq->n_pend_desc too large"));
  297         KASSERT(!txq->blocked, ("txq->blocked"));
  298 
  299         old_added = txq->added;
  300 
  301         /* Post the fragment list. */
  302         rc = efx_tx_qdesc_post(txq->common, txq->pend_desc, txq->n_pend_desc,
  303                           txq->reaped, &txq->added);
  304         KASSERT(rc == 0, ("efx_tx_qdesc_post() failed"));
  305 
  306         /* If efx_tx_qdesc_post() had to refragment, our information about
  307          * buffers to free may be associated with the wrong
  308          * descriptors.
  309          */
  310         KASSERT(txq->added - old_added == txq->n_pend_desc,
  311                 ("efx_tx_qdesc_post() refragmented descriptors"));
  312 
  313         level = txq->added - txq->reaped;
  314         KASSERT(level <= txq->entries, ("overfilled TX queue"));
  315 
  316         /* Clear the fragment list. */
  317         txq->n_pend_desc = 0;
  318 
  319         /*
  320          * Set the block level to ensure there is space to generate a
  321          * large number of descriptors for TSO.
  322          */
  323         block_level = EFX_TXQ_LIMIT(txq->entries) - txq->max_pkt_desc;
  324 
  325         /* Have we reached the block level? */
  326         if (level < block_level)
  327                 return;
  328 
  329         /* Reap, and check again */
  330         sfxge_tx_qreap(txq);
  331         level = txq->added - txq->reaped;
  332         if (level < block_level)
  333                 return;
  334 
  335         txq->blocked = 1;
  336 
  337         /*
  338          * Avoid a race with completion interrupt handling that could leave
  339          * the queue blocked.
  340          */
  341         mb();
  342         sfxge_tx_qreap(txq);
  343         level = txq->added - txq->reaped;
  344         if (level < block_level) {
  345                 mb();
  346                 txq->blocked = 0;
  347         }
  348 }
  349 
  350 static int sfxge_tx_queue_mbuf(struct sfxge_txq *txq, struct mbuf *mbuf)
  351 {
  352         bus_dmamap_t *used_map;
  353         bus_dmamap_t map;
  354         bus_dma_segment_t dma_seg[SFXGE_TX_MAPPING_MAX_SEG];
  355         unsigned int id;
  356         struct sfxge_tx_mapping *stmp;
  357         efx_desc_t *desc;
  358         int n_dma_seg;
  359         int rc;
  360         int i;
  361         int eop;
  362         int vlan_tagged;
  363 
  364         KASSERT(!txq->blocked, ("txq->blocked"));
  365 
  366 #if SFXGE_TX_PARSE_EARLY
  367         /*
  368          * If software TSO is used, we still need to copy packet header,
  369          * even if we have already parsed it early before enqueue.
  370          */
  371         if ((mbuf->m_pkthdr.csum_flags & CSUM_TSO) &&
  372             (txq->tso_fw_assisted == 0))
  373                 prefetch_read_many(mbuf->m_data);
  374 #else
  375         /*
  376          * Prefetch packet header since we need to parse it and extract
  377          * IP ID, TCP sequence number and flags.
  378          */
  379         if (mbuf->m_pkthdr.csum_flags & CSUM_TSO)
  380                 prefetch_read_many(mbuf->m_data);
  381 #endif
  382 
  383         if (__predict_false(txq->init_state != SFXGE_TXQ_STARTED)) {
  384                 rc = EINTR;
  385                 goto reject;
  386         }
  387 
  388         /* Load the packet for DMA. */
  389         id = txq->added & txq->ptr_mask;
  390         stmp = &txq->stmp[id];
  391         rc = bus_dmamap_load_mbuf_sg(txq->packet_dma_tag, stmp->map,
  392                                      mbuf, dma_seg, &n_dma_seg, 0);
  393         if (rc == EFBIG) {
  394                 /* Try again. */
  395                 struct mbuf *new_mbuf = m_collapse(mbuf, M_NOWAIT,
  396                                                    SFXGE_TX_MAPPING_MAX_SEG);
  397                 if (new_mbuf == NULL)
  398                         goto reject;
  399                 ++txq->collapses;
  400                 mbuf = new_mbuf;
  401                 rc = bus_dmamap_load_mbuf_sg(txq->packet_dma_tag,
  402                                              stmp->map, mbuf,
  403                                              dma_seg, &n_dma_seg, 0);
  404         }
  405         if (rc != 0)
  406                 goto reject;
  407 
  408         /* Make the packet visible to the hardware. */
  409         bus_dmamap_sync(txq->packet_dma_tag, stmp->map, BUS_DMASYNC_PREWRITE);
  410 
  411         used_map = &stmp->map;
  412 
  413         vlan_tagged = sfxge_tx_maybe_insert_tag(txq, mbuf);
  414         if (vlan_tagged) {
  415                 sfxge_next_stmp(txq, &stmp);
  416         }
  417         if (mbuf->m_pkthdr.csum_flags & CSUM_TSO) {
  418                 rc = sfxge_tx_queue_tso(txq, mbuf, dma_seg, n_dma_seg, vlan_tagged);
  419                 if (rc < 0)
  420                         goto reject_mapped;
  421                 stmp = &txq->stmp[(rc - 1) & txq->ptr_mask];
  422         } else {
  423                 /* Add the mapping to the fragment list, and set flags
  424                  * for the buffer.
  425                  */
  426 
  427                 i = 0;
  428                 for (;;) {
  429                         desc = &txq->pend_desc[i + vlan_tagged];
  430                         eop = (i == n_dma_seg - 1);
  431                         efx_tx_qdesc_dma_create(txq->common,
  432                                                 dma_seg[i].ds_addr,
  433                                                 dma_seg[i].ds_len,
  434                                                 eop,
  435                                                 desc);
  436                         if (eop)
  437                                 break;
  438                         i++;
  439                         sfxge_next_stmp(txq, &stmp);
  440                 }
  441                 txq->n_pend_desc = n_dma_seg + vlan_tagged;
  442         }
  443 
  444         /*
  445          * If the mapping required more than one descriptor
  446          * then we need to associate the DMA map with the last
  447          * descriptor, not the first.
  448          */
  449         if (used_map != &stmp->map) {
  450                 map = stmp->map;
  451                 stmp->map = *used_map;
  452                 *used_map = map;
  453         }
  454 
  455         stmp->u.mbuf = mbuf;
  456         stmp->flags = TX_BUF_UNMAP | TX_BUF_MBUF;
  457 
  458         /* Post the fragment list. */
  459         sfxge_tx_qlist_post(txq);
  460 
  461         return (0);
  462 
  463 reject_mapped:
  464         bus_dmamap_unload(txq->packet_dma_tag, *used_map);
  465 reject:
  466         /* Drop the packet on the floor. */
  467         m_freem(mbuf);
  468         ++txq->drops;
  469 
  470         return (rc);
  471 }
  472 
  473 /*
  474  * Drain the deferred packet list into the transmit queue.
  475  */
  476 static void
  477 sfxge_tx_qdpl_drain(struct sfxge_txq *txq)
  478 {
  479         struct sfxge_softc *sc;
  480         struct sfxge_tx_dpl *stdp;
  481         struct mbuf *mbuf, *next;
  482         unsigned int count;
  483         unsigned int non_tcp_count;
  484         unsigned int pushed;
  485         int rc;
  486 
  487         SFXGE_TXQ_LOCK_ASSERT_OWNED(txq);
  488 
  489         sc = txq->sc;
  490         stdp = &txq->dpl;
  491         pushed = txq->added;
  492 
  493         if (__predict_true(txq->init_state == SFXGE_TXQ_STARTED)) {
  494                 prefetch_read_many(sc->enp);
  495                 prefetch_read_many(txq->common);
  496         }
  497 
  498         mbuf = stdp->std_get;
  499         count = stdp->std_get_count;
  500         non_tcp_count = stdp->std_get_non_tcp_count;
  501 
  502         if (count > stdp->std_get_hiwat)
  503                 stdp->std_get_hiwat = count;
  504 
  505         while (count != 0) {
  506                 KASSERT(mbuf != NULL, ("mbuf == NULL"));
  507 
  508                 next = mbuf->m_nextpkt;
  509                 mbuf->m_nextpkt = NULL;
  510 
  511                 ETHER_BPF_MTAP(sc->ifnet, mbuf); /* packet capture */
  512 
  513                 if (next != NULL)
  514                         prefetch_read_many(next);
  515 
  516                 rc = sfxge_tx_queue_mbuf(txq, mbuf);
  517                 --count;
  518                 non_tcp_count -= sfxge_is_mbuf_non_tcp(mbuf);
  519                 mbuf = next;
  520                 if (rc != 0)
  521                         continue;
  522 
  523                 if (txq->blocked)
  524                         break;
  525 
  526                 /* Push the fragments to the hardware in batches. */
  527                 if (txq->added - pushed >= SFXGE_TX_BATCH) {
  528                         efx_tx_qpush(txq->common, txq->added, pushed);
  529                         pushed = txq->added;
  530                 }
  531         }
  532 
  533         if (count == 0) {
  534                 KASSERT(mbuf == NULL, ("mbuf != NULL"));
  535                 KASSERT(non_tcp_count == 0,
  536                         ("inconsistent TCP/non-TCP detection"));
  537                 stdp->std_get = NULL;
  538                 stdp->std_get_count = 0;
  539                 stdp->std_get_non_tcp_count = 0;
  540                 stdp->std_getp = &stdp->std_get;
  541         } else {
  542                 stdp->std_get = mbuf;
  543                 stdp->std_get_count = count;
  544                 stdp->std_get_non_tcp_count = non_tcp_count;
  545         }
  546 
  547         if (txq->added != pushed)
  548                 efx_tx_qpush(txq->common, txq->added, pushed);
  549 
  550         KASSERT(txq->blocked || stdp->std_get_count == 0,
  551                 ("queue unblocked but count is non-zero"));
  552 }
  553 
  554 #define SFXGE_TX_QDPL_PENDING(_txq)     ((_txq)->dpl.std_put != 0)
  555 
  556 /*
  557  * Service the deferred packet list.
  558  *
  559  * NOTE: drops the txq mutex!
  560  */
  561 static void
  562 sfxge_tx_qdpl_service(struct sfxge_txq *txq)
  563 {
  564         SFXGE_TXQ_LOCK_ASSERT_OWNED(txq);
  565 
  566         do {
  567                 if (SFXGE_TX_QDPL_PENDING(txq))
  568                         sfxge_tx_qdpl_swizzle(txq);
  569 
  570                 if (!txq->blocked)
  571                         sfxge_tx_qdpl_drain(txq);
  572 
  573                 SFXGE_TXQ_UNLOCK(txq);
  574         } while (SFXGE_TX_QDPL_PENDING(txq) &&
  575                  SFXGE_TXQ_TRYLOCK(txq));
  576 }
  577 
  578 /*
  579  * Put a packet on the deferred packet get-list.
  580  */
  581 static int
  582 sfxge_tx_qdpl_put_locked(struct sfxge_txq *txq, struct mbuf *mbuf)
  583 {
  584         struct sfxge_tx_dpl *stdp;
  585 
  586         stdp = &txq->dpl;
  587 
  588         KASSERT(mbuf->m_nextpkt == NULL, ("mbuf->m_nextpkt != NULL"));
  589 
  590         SFXGE_TXQ_LOCK_ASSERT_OWNED(txq);
  591 
  592         if (stdp->std_get_count >= stdp->std_get_max) {
  593                 txq->get_overflow++;
  594                 return (ENOBUFS);
  595         }
  596         if (sfxge_is_mbuf_non_tcp(mbuf)) {
  597                 if (stdp->std_get_non_tcp_count >=
  598                     stdp->std_get_non_tcp_max) {
  599                         txq->get_non_tcp_overflow++;
  600                         return (ENOBUFS);
  601                 }
  602                 stdp->std_get_non_tcp_count++;
  603         }
  604 
  605         *(stdp->std_getp) = mbuf;
  606         stdp->std_getp = &mbuf->m_nextpkt;
  607         stdp->std_get_count++;
  608 
  609         return (0);
  610 }
  611 
  612 /*
  613  * Put a packet on the deferred packet put-list.
  614  *
  615  * We overload the csum_data field in the mbuf to keep track of this length
  616  * because there is no cheap alternative to avoid races.
  617  */
  618 static int
  619 sfxge_tx_qdpl_put_unlocked(struct sfxge_txq *txq, struct mbuf *mbuf)
  620 {
  621         struct sfxge_tx_dpl *stdp;
  622         volatile uintptr_t *putp;
  623         uintptr_t old;
  624         uintptr_t new;
  625         unsigned int put_count;
  626 
  627         KASSERT(mbuf->m_nextpkt == NULL, ("mbuf->m_nextpkt != NULL"));
  628 
  629         SFXGE_TXQ_LOCK_ASSERT_NOTOWNED(txq);
  630 
  631         stdp = &txq->dpl;
  632         putp = &stdp->std_put;
  633         new = (uintptr_t)mbuf;
  634 
  635         do {
  636                 old = *putp;
  637                 if (old != 0) {
  638                         struct mbuf *mp = (struct mbuf *)old;
  639                         put_count = mp->m_pkthdr.csum_data;
  640                 } else
  641                         put_count = 0;
  642                 if (put_count >= stdp->std_put_max) {
  643                         atomic_add_long(&txq->put_overflow, 1);
  644                         return (ENOBUFS);
  645                 }
  646                 mbuf->m_pkthdr.csum_data = put_count + 1;
  647                 mbuf->m_nextpkt = (void *)old;
  648         } while (atomic_cmpset_ptr(putp, old, new) == 0);
  649 
  650         return (0);
  651 }
  652 
  653 /*
  654  * Called from if_transmit - will try to grab the txq lock and enqueue to the
  655  * put list if it succeeds, otherwise try to push onto the defer list if space.
  656  */
  657 static int
  658 sfxge_tx_packet_add(struct sfxge_txq *txq, struct mbuf *m)
  659 {
  660         int rc;
  661 
  662         if (!SFXGE_LINK_UP(txq->sc)) {
  663                 atomic_add_long(&txq->netdown_drops, 1);
  664                 return (ENETDOWN);
  665         }
  666 
  667         /*
  668          * Try to grab the txq lock.  If we are able to get the lock,
  669          * the packet will be appended to the "get list" of the deferred
  670          * packet list.  Otherwise, it will be pushed on the "put list".
  671          */
  672         if (SFXGE_TXQ_TRYLOCK(txq)) {
  673                 /* First swizzle put-list to get-list to keep order */
  674                 sfxge_tx_qdpl_swizzle(txq);
  675 
  676                 rc = sfxge_tx_qdpl_put_locked(txq, m);
  677 
  678                 /* Try to service the list. */
  679                 sfxge_tx_qdpl_service(txq);
  680                 /* Lock has been dropped. */
  681         } else {
  682                 rc = sfxge_tx_qdpl_put_unlocked(txq, m);
  683 
  684                 /*
  685                  * Try to grab the lock again.
  686                  *
  687                  * If we are able to get the lock, we need to process
  688                  * the deferred packet list.  If we are not able to get
  689                  * the lock, another thread is processing the list.
  690                  */
  691                 if ((rc == 0) && SFXGE_TXQ_TRYLOCK(txq)) {
  692                         sfxge_tx_qdpl_service(txq);
  693                         /* Lock has been dropped. */
  694                 }
  695         }
  696 
  697         SFXGE_TXQ_LOCK_ASSERT_NOTOWNED(txq);
  698 
  699         return (rc);
  700 }
  701 
  702 static void
  703 sfxge_tx_qdpl_flush(struct sfxge_txq *txq)
  704 {
  705         struct sfxge_tx_dpl *stdp = &txq->dpl;
  706         struct mbuf *mbuf, *next;
  707 
  708         SFXGE_TXQ_LOCK(txq);
  709 
  710         sfxge_tx_qdpl_swizzle(txq);
  711         for (mbuf = stdp->std_get; mbuf != NULL; mbuf = next) {
  712                 next = mbuf->m_nextpkt;
  713                 m_freem(mbuf);
  714         }
  715         stdp->std_get = NULL;
  716         stdp->std_get_count = 0;
  717         stdp->std_get_non_tcp_count = 0;
  718         stdp->std_getp = &stdp->std_get;
  719 
  720         SFXGE_TXQ_UNLOCK(txq);
  721 }
  722 
  723 void
  724 sfxge_if_qflush(struct ifnet *ifp)
  725 {
  726         struct sfxge_softc *sc;
  727         unsigned int i;
  728 
  729         sc = ifp->if_softc;
  730 
  731         for (i = 0; i < sc->txq_count; i++)
  732                 sfxge_tx_qdpl_flush(sc->txq[i]);
  733 }
  734 
  735 #if SFXGE_TX_PARSE_EARLY
  736 
  737 /* There is little space for user data in mbuf pkthdr, so we
  738  * use l*hlen fields which are not used by the driver otherwise
  739  * to store header offsets.
  740  * The fields are 8-bit, but it's ok, no header may be longer than 255 bytes.
  741  */
  742 
  743 
  744 #define TSO_MBUF_PROTO(_mbuf)    ((_mbuf)->m_pkthdr.PH_loc.sixteen[0])
  745 /* We abuse l5hlen here because PH_loc can hold only 64 bits of data */
  746 #define TSO_MBUF_FLAGS(_mbuf)    ((_mbuf)->m_pkthdr.l5hlen)
  747 #define TSO_MBUF_PACKETID(_mbuf) ((_mbuf)->m_pkthdr.PH_loc.sixteen[1])
  748 #define TSO_MBUF_SEQNUM(_mbuf)   ((_mbuf)->m_pkthdr.PH_loc.thirtytwo[1])
  749 
  750 static void sfxge_parse_tx_packet(struct mbuf *mbuf)
  751 {
  752         struct ether_header *eh = mtod(mbuf, struct ether_header *);
  753         const struct tcphdr *th;
  754         struct tcphdr th_copy;
  755 
  756         /* Find network protocol and header */
  757         TSO_MBUF_PROTO(mbuf) = eh->ether_type;
  758         if (TSO_MBUF_PROTO(mbuf) == htons(ETHERTYPE_VLAN)) {
  759                 struct ether_vlan_header *veh =
  760                         mtod(mbuf, struct ether_vlan_header *);
  761                 TSO_MBUF_PROTO(mbuf) = veh->evl_proto;
  762                 mbuf->m_pkthdr.l2hlen = sizeof(*veh);
  763         } else {
  764                 mbuf->m_pkthdr.l2hlen = sizeof(*eh);
  765         }
  766 
  767         /* Find TCP header */
  768         if (TSO_MBUF_PROTO(mbuf) == htons(ETHERTYPE_IP)) {
  769                 const struct ip *iph = (const struct ip *)mtodo(mbuf, mbuf->m_pkthdr.l2hlen);
  770 
  771                 KASSERT(iph->ip_p == IPPROTO_TCP,
  772                         ("TSO required on non-TCP packet"));
  773                 mbuf->m_pkthdr.l3hlen = mbuf->m_pkthdr.l2hlen + 4 * iph->ip_hl;
  774                 TSO_MBUF_PACKETID(mbuf) = iph->ip_id;
  775         } else {
  776                 KASSERT(TSO_MBUF_PROTO(mbuf) == htons(ETHERTYPE_IPV6),
  777                         ("TSO required on non-IP packet"));
  778                 KASSERT(((const struct ip6_hdr *)mtodo(mbuf, mbuf->m_pkthdr.l2hlen))->ip6_nxt ==
  779                         IPPROTO_TCP,
  780                         ("TSO required on non-TCP packet"));
  781                 mbuf->m_pkthdr.l3hlen = mbuf->m_pkthdr.l2hlen + sizeof(struct ip6_hdr);
  782                 TSO_MBUF_PACKETID(mbuf) = 0;
  783         }
  784 
  785         KASSERT(mbuf->m_len >= mbuf->m_pkthdr.l3hlen,
  786                 ("network header is fragmented in mbuf"));
  787 
  788         /* We need TCP header including flags (window is the next) */
  789         if (mbuf->m_len < mbuf->m_pkthdr.l3hlen + offsetof(struct tcphdr, th_win)) {
  790                 m_copydata(mbuf, mbuf->m_pkthdr.l3hlen, sizeof(th_copy),
  791                            (caddr_t)&th_copy);
  792                 th = &th_copy;
  793         } else {
  794                 th = (const struct tcphdr *)mtodo(mbuf, mbuf->m_pkthdr.l3hlen);
  795         }
  796 
  797         mbuf->m_pkthdr.l4hlen = mbuf->m_pkthdr.l3hlen + 4 * th->th_off;
  798         TSO_MBUF_SEQNUM(mbuf) = ntohl(th->th_seq);
  799 
  800         /* These flags must not be duplicated */
  801         /*
  802          * RST should not be duplicated as well, but FreeBSD kernel
  803          * generates TSO packets with RST flag. So, do not assert
  804          * its absence.
  805          */
  806         KASSERT(!(th->th_flags & (TH_URG | TH_SYN)),
  807                 ("incompatible TCP flag 0x%x on TSO packet",
  808                  th->th_flags & (TH_URG | TH_SYN)));
  809         TSO_MBUF_FLAGS(mbuf) = th->th_flags;
  810 }
  811 #endif
  812 
  813 /*
  814  * TX start -- called by the stack.
  815  */
  816 int
  817 sfxge_if_transmit(struct ifnet *ifp, struct mbuf *m)
  818 {
  819         struct sfxge_softc *sc;
  820         struct sfxge_txq *txq;
  821         int rc;
  822 
  823         sc = (struct sfxge_softc *)ifp->if_softc;
  824 
  825         /*
  826          * Transmit may be called when interface is up from the kernel
  827          * point of view, but not yet up (in progress) from the driver
  828          * point of view. I.e. link aggregation bring up.
  829          * Transmit may be called when interface is up from the driver
  830          * point of view, but already down from the kernel point of
  831          * view. I.e. Rx when interface shutdown is in progress.
  832          */
  833         KASSERT((ifp->if_flags & IFF_UP) || (sc->if_flags & IFF_UP),
  834                 ("interface not up"));
  835 
  836         /* Pick the desired transmit queue. */
  837         if (m->m_pkthdr.csum_flags &
  838             (CSUM_DELAY_DATA | CSUM_TCP_IPV6 | CSUM_UDP_IPV6 | CSUM_TSO)) {
  839                 int index = 0;
  840 
  841 #ifdef RSS
  842                 uint32_t bucket_id;
  843 
  844                 /*
  845                  * Select a TX queue which matches the corresponding
  846                  * RX queue for the hash in order to assign both
  847                  * TX and RX parts of the flow to the same CPU
  848                  */
  849                 if (rss_m2bucket(m, &bucket_id) == 0)
  850                         index = bucket_id % (sc->txq_count - (SFXGE_TXQ_NTYPES - 1));
  851 #else
  852                 /* check if flowid is set */
  853                 if (M_HASHTYPE_GET(m) != M_HASHTYPE_NONE) {
  854                         uint32_t hash = m->m_pkthdr.flowid;
  855                         uint32_t idx = hash % nitems(sc->rx_indir_table);
  856 
  857                         index = sc->rx_indir_table[idx];
  858                 }
  859 #endif
  860 #if SFXGE_TX_PARSE_EARLY
  861                 if (m->m_pkthdr.csum_flags & CSUM_TSO)
  862                         sfxge_parse_tx_packet(m);
  863 #endif
  864                 txq = sc->txq[SFXGE_TXQ_IP_TCP_UDP_CKSUM + index];
  865         } else if (m->m_pkthdr.csum_flags & CSUM_DELAY_IP) {
  866                 txq = sc->txq[SFXGE_TXQ_IP_CKSUM];
  867         } else {
  868                 txq = sc->txq[SFXGE_TXQ_NON_CKSUM];
  869         }
  870 
  871         rc = sfxge_tx_packet_add(txq, m);
  872         if (rc != 0)
  873                 m_freem(m);
  874 
  875         return (rc);
  876 }
  877 
  878 /*
  879  * Software "TSO".  Not quite as good as doing it in hardware, but
  880  * still faster than segmenting in the stack.
  881  */
  882 
  883 struct sfxge_tso_state {
  884         /* Output position */
  885         unsigned out_len;       /* Remaining length in current segment */
  886         unsigned seqnum;        /* Current sequence number */
  887         unsigned packet_space;  /* Remaining space in current packet */
  888         unsigned segs_space;    /* Remaining number of DMA segments
  889                                    for the packet (FATSOv2 only) */
  890 
  891         /* Input position */
  892         uint64_t dma_addr;      /* DMA address of current position */
  893         unsigned in_len;        /* Remaining length in current mbuf */
  894 
  895         const struct mbuf *mbuf; /* Input mbuf (head of chain) */
  896         u_short protocol;       /* Network protocol (after VLAN decap) */
  897         ssize_t nh_off;         /* Offset of network header */
  898         ssize_t tcph_off;       /* Offset of TCP header */
  899         unsigned header_len;    /* Number of bytes of header */
  900         unsigned seg_size;      /* TCP segment size */
  901         int fw_assisted;        /* Use FW-assisted TSO */
  902         u_short packet_id;      /* IPv4 packet ID from the original packet */
  903         uint8_t tcp_flags;      /* TCP flags */
  904         efx_desc_t header_desc; /* Precomputed header descriptor for
  905                                  * FW-assisted TSO */
  906 };
  907 
  908 #if !SFXGE_TX_PARSE_EARLY
  909 static const struct ip *tso_iph(const struct sfxge_tso_state *tso)
  910 {
  911         KASSERT(tso->protocol == htons(ETHERTYPE_IP),
  912                 ("tso_iph() in non-IPv4 state"));
  913         return (const struct ip *)(tso->mbuf->m_data + tso->nh_off);
  914 }
  915 
  916 static __unused const struct ip6_hdr *tso_ip6h(const struct sfxge_tso_state *tso)
  917 {
  918         KASSERT(tso->protocol == htons(ETHERTYPE_IPV6),
  919                 ("tso_ip6h() in non-IPv6 state"));
  920         return (const struct ip6_hdr *)(tso->mbuf->m_data + tso->nh_off);
  921 }
  922 
  923 static const struct tcphdr *tso_tcph(const struct sfxge_tso_state *tso)
  924 {
  925         return (const struct tcphdr *)(tso->mbuf->m_data + tso->tcph_off);
  926 }
  927 #endif
  928 
  929 
  930 /* Size of preallocated TSO header buffers.  Larger blocks must be
  931  * allocated from the heap.
  932  */
  933 #define TSOH_STD_SIZE   128
  934 
  935 /* At most half the descriptors in the queue at any time will refer to
  936  * a TSO header buffer, since they must always be followed by a
  937  * payload descriptor referring to an mbuf.
  938  */
  939 #define TSOH_COUNT(_txq_entries)        ((_txq_entries) / 2u)
  940 #define TSOH_PER_PAGE   (PAGE_SIZE / TSOH_STD_SIZE)
  941 #define TSOH_PAGE_COUNT(_txq_entries)   \
  942         howmany(TSOH_COUNT(_txq_entries), TSOH_PER_PAGE)
  943 
  944 static int tso_init(struct sfxge_txq *txq)
  945 {
  946         struct sfxge_softc *sc = txq->sc;
  947         unsigned int tsoh_page_count = TSOH_PAGE_COUNT(sc->txq_entries);
  948         int i, rc;
  949 
  950         /* Allocate TSO header buffers */
  951         txq->tsoh_buffer = malloc(tsoh_page_count * sizeof(txq->tsoh_buffer[0]),
  952                                   M_SFXGE, M_WAITOK);
  953 
  954         for (i = 0; i < tsoh_page_count; i++) {
  955                 rc = sfxge_dma_alloc(sc, PAGE_SIZE, &txq->tsoh_buffer[i]);
  956                 if (rc != 0)
  957                         goto fail;
  958         }
  959 
  960         return (0);
  961 
  962 fail:
  963         while (i-- > 0)
  964                 sfxge_dma_free(&txq->tsoh_buffer[i]);
  965         free(txq->tsoh_buffer, M_SFXGE);
  966         txq->tsoh_buffer = NULL;
  967         return (rc);
  968 }
  969 
  970 static void tso_fini(struct sfxge_txq *txq)
  971 {
  972         int i;
  973 
  974         if (txq->tsoh_buffer != NULL) {
  975                 for (i = 0; i < TSOH_PAGE_COUNT(txq->sc->txq_entries); i++)
  976                         sfxge_dma_free(&txq->tsoh_buffer[i]);
  977                 free(txq->tsoh_buffer, M_SFXGE);
  978         }
  979 }
  980 
  981 static void tso_start(struct sfxge_txq *txq, struct sfxge_tso_state *tso,
  982                       const bus_dma_segment_t *hdr_dma_seg,
  983                       struct mbuf *mbuf)
  984 {
  985         const efx_nic_cfg_t *encp = efx_nic_cfg_get(txq->sc->enp);
  986 #if !SFXGE_TX_PARSE_EARLY
  987         struct ether_header *eh = mtod(mbuf, struct ether_header *);
  988         const struct tcphdr *th;
  989         struct tcphdr th_copy;
  990 #endif
  991 
  992         tso->fw_assisted = txq->tso_fw_assisted;
  993         tso->mbuf = mbuf;
  994 
  995         /* Find network protocol and header */
  996 #if !SFXGE_TX_PARSE_EARLY
  997         tso->protocol = eh->ether_type;
  998         if (tso->protocol == htons(ETHERTYPE_VLAN)) {
  999                 struct ether_vlan_header *veh =
 1000                         mtod(mbuf, struct ether_vlan_header *);
 1001                 tso->protocol = veh->evl_proto;
 1002                 tso->nh_off = sizeof(*veh);
 1003         } else {
 1004                 tso->nh_off = sizeof(*eh);
 1005         }
 1006 #else
 1007         tso->protocol = TSO_MBUF_PROTO(mbuf);
 1008         tso->nh_off = mbuf->m_pkthdr.l2hlen;
 1009         tso->tcph_off = mbuf->m_pkthdr.l3hlen;
 1010         tso->packet_id = ntohs(TSO_MBUF_PACKETID(mbuf));
 1011 #endif
 1012 
 1013 #if !SFXGE_TX_PARSE_EARLY
 1014         /* Find TCP header */
 1015         if (tso->protocol == htons(ETHERTYPE_IP)) {
 1016                 KASSERT(tso_iph(tso)->ip_p == IPPROTO_TCP,
 1017                         ("TSO required on non-TCP packet"));
 1018                 tso->tcph_off = tso->nh_off + 4 * tso_iph(tso)->ip_hl;
 1019                 tso->packet_id = ntohs(tso_iph(tso)->ip_id);
 1020         } else {
 1021                 KASSERT(tso->protocol == htons(ETHERTYPE_IPV6),
 1022                         ("TSO required on non-IP packet"));
 1023                 KASSERT(tso_ip6h(tso)->ip6_nxt == IPPROTO_TCP,
 1024                         ("TSO required on non-TCP packet"));
 1025                 tso->tcph_off = tso->nh_off + sizeof(struct ip6_hdr);
 1026                 tso->packet_id = 0;
 1027         }
 1028 #endif
 1029 
 1030 
 1031         if (tso->fw_assisted &&
 1032             __predict_false(tso->tcph_off >
 1033                             encp->enc_tx_tso_tcp_header_offset_limit)) {
 1034                 tso->fw_assisted = 0;
 1035         }
 1036 
 1037 
 1038 #if !SFXGE_TX_PARSE_EARLY
 1039         KASSERT(mbuf->m_len >= tso->tcph_off,
 1040                 ("network header is fragmented in mbuf"));
 1041         /* We need TCP header including flags (window is the next) */
 1042         if (mbuf->m_len < tso->tcph_off + offsetof(struct tcphdr, th_win)) {
 1043                 m_copydata(tso->mbuf, tso->tcph_off, sizeof(th_copy),
 1044                            (caddr_t)&th_copy);
 1045                 th = &th_copy;
 1046         } else {
 1047                 th = tso_tcph(tso);
 1048         }
 1049         tso->header_len = tso->tcph_off + 4 * th->th_off;
 1050 #else
 1051         tso->header_len = mbuf->m_pkthdr.l4hlen;
 1052 #endif
 1053         tso->seg_size = mbuf->m_pkthdr.tso_segsz;
 1054 
 1055 #if !SFXGE_TX_PARSE_EARLY
 1056         tso->seqnum = ntohl(th->th_seq);
 1057 
 1058         /* These flags must not be duplicated */
 1059         /*
 1060          * RST should not be duplicated as well, but FreeBSD kernel
 1061          * generates TSO packets with RST flag. So, do not assert
 1062          * its absence.
 1063          */
 1064         KASSERT(!(th->th_flags & (TH_URG | TH_SYN)),
 1065                 ("incompatible TCP flag 0x%x on TSO packet",
 1066                  th->th_flags & (TH_URG | TH_SYN)));
 1067         tso->tcp_flags = th->th_flags;
 1068 #else
 1069         tso->seqnum = TSO_MBUF_SEQNUM(mbuf);
 1070         tso->tcp_flags = TSO_MBUF_FLAGS(mbuf);
 1071 #endif
 1072 
 1073         tso->out_len = mbuf->m_pkthdr.len - tso->header_len;
 1074 
 1075         if (tso->fw_assisted) {
 1076                 if (hdr_dma_seg->ds_len >= tso->header_len)
 1077                         efx_tx_qdesc_dma_create(txq->common,
 1078                                                 hdr_dma_seg->ds_addr,
 1079                                                 tso->header_len,
 1080                                                 B_FALSE,
 1081                                                 &tso->header_desc);
 1082                 else
 1083                         tso->fw_assisted = 0;
 1084         }
 1085 }
 1086 
 1087 /*
 1088  * tso_fill_packet_with_fragment - form descriptors for the current fragment
 1089  *
 1090  * Form descriptors for the current fragment, until we reach the end
 1091  * of fragment or end-of-packet.  Return 0 on success, 1 if not enough
 1092  * space.
 1093  */
 1094 static void tso_fill_packet_with_fragment(struct sfxge_txq *txq,
 1095                                           struct sfxge_tso_state *tso)
 1096 {
 1097         efx_desc_t *desc;
 1098         int n;
 1099         uint64_t dma_addr = tso->dma_addr;
 1100         boolean_t eop;
 1101 
 1102         if (tso->in_len == 0 || tso->packet_space == 0)
 1103                 return;
 1104 
 1105         KASSERT(tso->in_len > 0, ("TSO input length went negative"));
 1106         KASSERT(tso->packet_space > 0, ("TSO packet space went negative"));
 1107 
 1108         if (tso->fw_assisted & SFXGE_FATSOV2) {
 1109                 n = tso->in_len;
 1110                 tso->out_len -= n;
 1111                 tso->seqnum += n;
 1112                 tso->in_len = 0;
 1113                 if (n < tso->packet_space) {
 1114                         tso->packet_space -= n;
 1115                         tso->segs_space--;
 1116                 } else {
 1117                         tso->packet_space = tso->seg_size -
 1118                             (n - tso->packet_space) % tso->seg_size;
 1119                         tso->segs_space =
 1120                             EFX_TX_FATSOV2_DMA_SEGS_PER_PKT_MAX - 1 -
 1121                             (tso->packet_space != tso->seg_size);
 1122                 }
 1123         } else {
 1124                 n = min(tso->in_len, tso->packet_space);
 1125                 tso->packet_space -= n;
 1126                 tso->out_len -= n;
 1127                 tso->dma_addr += n;
 1128                 tso->in_len -= n;
 1129         }
 1130 
 1131         /*
 1132          * It is OK to use binary OR below to avoid extra branching
 1133          * since all conditions may always be checked.
 1134          */
 1135         eop = (tso->out_len == 0) | (tso->packet_space == 0) |
 1136             (tso->segs_space == 0);
 1137 
 1138         desc = &txq->pend_desc[txq->n_pend_desc++];
 1139         efx_tx_qdesc_dma_create(txq->common, dma_addr, n, eop, desc);
 1140 }
 1141 
 1142 /* Callback from bus_dmamap_load() for long TSO headers. */
 1143 static void tso_map_long_header(void *dma_addr_ret,
 1144                                 bus_dma_segment_t *segs, int nseg,
 1145                                 int error)
 1146 {
 1147         *(uint64_t *)dma_addr_ret = ((__predict_true(error == 0) &&
 1148                                       __predict_true(nseg == 1)) ?
 1149                                      segs->ds_addr : 0);
 1150 }
 1151 
 1152 /*
 1153  * tso_start_new_packet - generate a new header and prepare for the new packet
 1154  *
 1155  * Generate a new header and prepare for the new packet.  Return 0 on
 1156  * success, or an error code if failed to alloc header.
 1157  */
 1158 static int tso_start_new_packet(struct sfxge_txq *txq,
 1159                                 struct sfxge_tso_state *tso,
 1160                                 unsigned int *idp)
 1161 {
 1162         unsigned int id = *idp;
 1163         struct tcphdr *tsoh_th;
 1164         unsigned ip_length;
 1165         caddr_t header;
 1166         uint64_t dma_addr;
 1167         bus_dmamap_t map;
 1168         efx_desc_t *desc;
 1169         int rc;
 1170 
 1171         if (tso->fw_assisted) {
 1172                 if (tso->fw_assisted & SFXGE_FATSOV2) {
 1173                         /* Add 2 FATSOv2 option descriptors */
 1174                         desc = &txq->pend_desc[txq->n_pend_desc];
 1175                         efx_tx_qdesc_tso2_create(txq->common,
 1176                                                  tso->packet_id,
 1177                                                  tso->seqnum,
 1178                                                  tso->seg_size,
 1179                                                  desc,
 1180                                                  EFX_TX_FATSOV2_OPT_NDESCS);
 1181                         desc += EFX_TX_FATSOV2_OPT_NDESCS;
 1182                         txq->n_pend_desc += EFX_TX_FATSOV2_OPT_NDESCS;
 1183                         KASSERT(txq->stmp[id].flags == 0, ("stmp flags are not 0"));
 1184                         id = (id + EFX_TX_FATSOV2_OPT_NDESCS) & txq->ptr_mask;
 1185 
 1186                         tso->segs_space =
 1187                             EFX_TX_FATSOV2_DMA_SEGS_PER_PKT_MAX - 1;
 1188                 } else {
 1189                         uint8_t tcp_flags = tso->tcp_flags;
 1190 
 1191                         if (tso->out_len > tso->seg_size)
 1192                                 tcp_flags &= ~(TH_FIN | TH_PUSH);
 1193 
 1194                         /* Add FATSOv1 option descriptor */
 1195                         desc = &txq->pend_desc[txq->n_pend_desc++];
 1196                         efx_tx_qdesc_tso_create(txq->common,
 1197                                                 tso->packet_id,
 1198                                                 tso->seqnum,
 1199                                                 tcp_flags,
 1200                                                 desc++);
 1201                         KASSERT(txq->stmp[id].flags == 0, ("stmp flags are not 0"));
 1202                         id = (id + 1) & txq->ptr_mask;
 1203 
 1204                         tso->seqnum += tso->seg_size;
 1205                         tso->segs_space = UINT_MAX;
 1206                 }
 1207 
 1208                 /* Header DMA descriptor */
 1209                 *desc = tso->header_desc;
 1210                 txq->n_pend_desc++;
 1211                 KASSERT(txq->stmp[id].flags == 0, ("stmp flags are not 0"));
 1212                 id = (id + 1) & txq->ptr_mask;
 1213         } else {
 1214                 /* Allocate a DMA-mapped header buffer. */
 1215                 if (__predict_true(tso->header_len <= TSOH_STD_SIZE)) {
 1216                         unsigned int page_index = (id / 2) / TSOH_PER_PAGE;
 1217                         unsigned int buf_index = (id / 2) % TSOH_PER_PAGE;
 1218 
 1219                         header = (txq->tsoh_buffer[page_index].esm_base +
 1220                                   buf_index * TSOH_STD_SIZE);
 1221                         dma_addr = (txq->tsoh_buffer[page_index].esm_addr +
 1222                                     buf_index * TSOH_STD_SIZE);
 1223                         map = txq->tsoh_buffer[page_index].esm_map;
 1224 
 1225                         KASSERT(txq->stmp[id].flags == 0,
 1226                                 ("stmp flags are not 0"));
 1227                 } else {
 1228                         struct sfxge_tx_mapping *stmp = &txq->stmp[id];
 1229 
 1230                         /* We cannot use bus_dmamem_alloc() as that may sleep */
 1231                         header = malloc(tso->header_len, M_SFXGE, M_NOWAIT);
 1232                         if (__predict_false(!header))
 1233                                 return (ENOMEM);
 1234                         rc = bus_dmamap_load(txq->packet_dma_tag, stmp->map,
 1235                                              header, tso->header_len,
 1236                                              tso_map_long_header, &dma_addr,
 1237                                              BUS_DMA_NOWAIT);
 1238                         if (__predict_false(dma_addr == 0)) {
 1239                                 if (rc == 0) {
 1240                                         /* Succeeded but got >1 segment */
 1241                                         bus_dmamap_unload(txq->packet_dma_tag,
 1242                                                           stmp->map);
 1243                                         rc = EINVAL;
 1244                                 }
 1245                                 free(header, M_SFXGE);
 1246                                 return (rc);
 1247                         }
 1248                         map = stmp->map;
 1249 
 1250                         txq->tso_long_headers++;
 1251                         stmp->u.heap_buf = header;
 1252                         stmp->flags = TX_BUF_UNMAP;
 1253                 }
 1254 
 1255                 tsoh_th = (struct tcphdr *)(header + tso->tcph_off);
 1256 
 1257                 /* Copy and update the headers. */
 1258                 m_copydata(tso->mbuf, 0, tso->header_len, header);
 1259 
 1260                 tsoh_th->th_seq = htonl(tso->seqnum);
 1261                 tso->seqnum += tso->seg_size;
 1262                 if (tso->out_len > tso->seg_size) {
 1263                         /* This packet will not finish the TSO burst. */
 1264                         ip_length = tso->header_len - tso->nh_off + tso->seg_size;
 1265                         tsoh_th->th_flags &= ~(TH_FIN | TH_PUSH);
 1266                 } else {
 1267                         /* This packet will be the last in the TSO burst. */
 1268                         ip_length = tso->header_len - tso->nh_off + tso->out_len;
 1269                 }
 1270 
 1271                 if (tso->protocol == htons(ETHERTYPE_IP)) {
 1272                         struct ip *tsoh_iph = (struct ip *)(header + tso->nh_off);
 1273                         tsoh_iph->ip_len = htons(ip_length);
 1274                         /* XXX We should increment ip_id, but FreeBSD doesn't
 1275                          * currently allocate extra IDs for multiple segments.
 1276                          */
 1277                 } else {
 1278                         struct ip6_hdr *tsoh_iph =
 1279                                 (struct ip6_hdr *)(header + tso->nh_off);
 1280                         tsoh_iph->ip6_plen = htons(ip_length - sizeof(*tsoh_iph));
 1281                 }
 1282 
 1283                 /* Make the header visible to the hardware. */
 1284                 bus_dmamap_sync(txq->packet_dma_tag, map, BUS_DMASYNC_PREWRITE);
 1285 
 1286                 /* Form a descriptor for this header. */
 1287                 desc = &txq->pend_desc[txq->n_pend_desc++];
 1288                 efx_tx_qdesc_dma_create(txq->common,
 1289                                         dma_addr,
 1290                                         tso->header_len,
 1291                                         0,
 1292                                         desc);
 1293                 id = (id + 1) & txq->ptr_mask;
 1294 
 1295                 tso->segs_space = UINT_MAX;
 1296         }
 1297         tso->packet_space = tso->seg_size;
 1298         txq->tso_packets++;
 1299         *idp = id;
 1300 
 1301         return (0);
 1302 }
 1303 
 1304 static int
 1305 sfxge_tx_queue_tso(struct sfxge_txq *txq, struct mbuf *mbuf,
 1306                    const bus_dma_segment_t *dma_seg, int n_dma_seg,
 1307                    int vlan_tagged)
 1308 {
 1309         struct sfxge_tso_state tso;
 1310         unsigned int id;
 1311         unsigned skipped = 0;
 1312 
 1313         tso_start(txq, &tso, dma_seg, mbuf);
 1314 
 1315         while (dma_seg->ds_len + skipped <= tso.header_len) {
 1316                 skipped += dma_seg->ds_len;
 1317                 --n_dma_seg;
 1318                 KASSERT(n_dma_seg, ("no payload found in TSO packet"));
 1319                 ++dma_seg;
 1320         }
 1321         tso.in_len = dma_seg->ds_len - (tso.header_len - skipped);
 1322         tso.dma_addr = dma_seg->ds_addr + (tso.header_len - skipped);
 1323 
 1324         id = (txq->added + vlan_tagged) & txq->ptr_mask;
 1325         if (__predict_false(tso_start_new_packet(txq, &tso, &id)))
 1326                 return (-1);
 1327 
 1328         while (1) {
 1329                 tso_fill_packet_with_fragment(txq, &tso);
 1330                 /* Exactly one DMA descriptor is added */
 1331                 KASSERT(txq->stmp[id].flags == 0, ("stmp flags are not 0"));
 1332                 id = (id + 1) & txq->ptr_mask;
 1333 
 1334                 /* Move onto the next fragment? */
 1335                 if (tso.in_len == 0) {
 1336                         --n_dma_seg;
 1337                         if (n_dma_seg == 0)
 1338                                 break;
 1339                         ++dma_seg;
 1340                         tso.in_len = dma_seg->ds_len;
 1341                         tso.dma_addr = dma_seg->ds_addr;
 1342                 }
 1343 
 1344                 /* End of packet? */
 1345                 if ((tso.packet_space == 0) | (tso.segs_space == 0)) {
 1346                         unsigned int n_fatso_opt_desc =
 1347                             (tso.fw_assisted & SFXGE_FATSOV2) ?
 1348                             EFX_TX_FATSOV2_OPT_NDESCS :
 1349                             (tso.fw_assisted & SFXGE_FATSOV1) ? 1 : 0;
 1350 
 1351                         /* If the queue is now full due to tiny MSS,
 1352                          * or we can't create another header, discard
 1353                          * the remainder of the input mbuf but do not
 1354                          * roll back the work we have done.
 1355                          */
 1356                         if (txq->n_pend_desc + n_fatso_opt_desc +
 1357                             1 /* header */ + n_dma_seg > txq->max_pkt_desc) {
 1358                                 txq->tso_pdrop_too_many++;
 1359                                 break;
 1360                         }
 1361                         if (__predict_false(tso_start_new_packet(txq, &tso,
 1362                                                                  &id))) {
 1363                                 txq->tso_pdrop_no_rsrc++;
 1364                                 break;
 1365                         }
 1366                 }
 1367         }
 1368 
 1369         txq->tso_bursts++;
 1370         return (id);
 1371 }
 1372 
 1373 static void
 1374 sfxge_tx_qunblock(struct sfxge_txq *txq)
 1375 {
 1376         struct sfxge_softc *sc;
 1377         struct sfxge_evq *evq;
 1378 
 1379         sc = txq->sc;
 1380         evq = sc->evq[txq->evq_index];
 1381 
 1382         SFXGE_EVQ_LOCK_ASSERT_OWNED(evq);
 1383 
 1384         if (__predict_false(txq->init_state != SFXGE_TXQ_STARTED))
 1385                 return;
 1386 
 1387         SFXGE_TXQ_LOCK(txq);
 1388 
 1389         if (txq->blocked) {
 1390                 unsigned int level;
 1391 
 1392                 level = txq->added - txq->completed;
 1393                 if (level <= SFXGE_TXQ_UNBLOCK_LEVEL(txq->entries)) {
 1394                         /* reaped must be in sync with blocked */
 1395                         sfxge_tx_qreap(txq);
 1396                         txq->blocked = 0;
 1397                 }
 1398         }
 1399 
 1400         sfxge_tx_qdpl_service(txq);
 1401         /* note: lock has been dropped */
 1402 }
 1403 
 1404 void
 1405 sfxge_tx_qflush_done(struct sfxge_txq *txq)
 1406 {
 1407 
 1408         txq->flush_state = SFXGE_FLUSH_DONE;
 1409 }
 1410 
 1411 static void
 1412 sfxge_tx_qstop(struct sfxge_softc *sc, unsigned int index)
 1413 {
 1414         struct sfxge_txq *txq;
 1415         struct sfxge_evq *evq;
 1416         unsigned int count;
 1417 
 1418         SFXGE_ADAPTER_LOCK_ASSERT_OWNED(sc);
 1419 
 1420         txq = sc->txq[index];
 1421         evq = sc->evq[txq->evq_index];
 1422 
 1423         SFXGE_EVQ_LOCK(evq);
 1424         SFXGE_TXQ_LOCK(txq);
 1425 
 1426         KASSERT(txq->init_state == SFXGE_TXQ_STARTED,
 1427             ("txq->init_state != SFXGE_TXQ_STARTED"));
 1428 
 1429         txq->init_state = SFXGE_TXQ_INITIALIZED;
 1430 
 1431         if (txq->flush_state != SFXGE_FLUSH_DONE) {
 1432                 txq->flush_state = SFXGE_FLUSH_PENDING;
 1433 
 1434                 SFXGE_EVQ_UNLOCK(evq);
 1435                 SFXGE_TXQ_UNLOCK(txq);
 1436 
 1437                 /* Flush the transmit queue. */
 1438                 if (efx_tx_qflush(txq->common) != 0) {
 1439                         log(LOG_ERR, "%s: Flushing Tx queue %u failed\n",
 1440                             device_get_nameunit(sc->dev), index);
 1441                         txq->flush_state = SFXGE_FLUSH_DONE;
 1442                 } else {
 1443                         count = 0;
 1444                         do {
 1445                                 /* Spin for 100ms. */
 1446                                 DELAY(100000);
 1447                                 if (txq->flush_state != SFXGE_FLUSH_PENDING)
 1448                                         break;
 1449                         } while (++count < 20);
 1450                 }
 1451                 SFXGE_EVQ_LOCK(evq);
 1452                 SFXGE_TXQ_LOCK(txq);
 1453 
 1454                 KASSERT(txq->flush_state != SFXGE_FLUSH_FAILED,
 1455                     ("txq->flush_state == SFXGE_FLUSH_FAILED"));
 1456 
 1457                 if (txq->flush_state != SFXGE_FLUSH_DONE) {
 1458                         /* Flush timeout */
 1459                         log(LOG_ERR, "%s: Cannot flush Tx queue %u\n",
 1460                             device_get_nameunit(sc->dev), index);
 1461                         txq->flush_state = SFXGE_FLUSH_DONE;
 1462                 }
 1463         }
 1464 
 1465         txq->blocked = 0;
 1466         txq->pending = txq->added;
 1467 
 1468         sfxge_tx_qcomplete(txq, evq);
 1469         KASSERT(txq->completed == txq->added,
 1470             ("txq->completed != txq->added"));
 1471 
 1472         sfxge_tx_qreap(txq);
 1473         KASSERT(txq->reaped == txq->completed,
 1474             ("txq->reaped != txq->completed"));
 1475 
 1476         txq->added = 0;
 1477         txq->pending = 0;
 1478         txq->completed = 0;
 1479         txq->reaped = 0;
 1480 
 1481         /* Destroy the common code transmit queue. */
 1482         efx_tx_qdestroy(txq->common);
 1483         txq->common = NULL;
 1484 
 1485         efx_sram_buf_tbl_clear(sc->enp, txq->buf_base_id,
 1486             EFX_TXQ_NBUFS(sc->txq_entries));
 1487 
 1488         SFXGE_EVQ_UNLOCK(evq);
 1489         SFXGE_TXQ_UNLOCK(txq);
 1490 }
 1491 
 1492 /*
 1493  * Estimate maximum number of Tx descriptors required for TSO packet.
 1494  * With minimum MSS and maximum mbuf length we might need more (even
 1495  * than a ring-ful of descriptors), but this should not happen in
 1496  * practice except due to deliberate attack.  In that case we will
 1497  * truncate the output at a packet boundary.
 1498  */
 1499 static unsigned int
 1500 sfxge_tx_max_pkt_desc(const struct sfxge_softc *sc, enum sfxge_txq_type type,
 1501                       unsigned int tso_fw_assisted)
 1502 {
 1503         /* One descriptor for every input fragment */
 1504         unsigned int max_descs = SFXGE_TX_MAPPING_MAX_SEG;
 1505         unsigned int sw_tso_max_descs;
 1506         unsigned int fa_tso_v1_max_descs = 0;
 1507         unsigned int fa_tso_v2_max_descs = 0;
 1508 
 1509         /* VLAN tagging Tx option descriptor may be required */
 1510         if (efx_nic_cfg_get(sc->enp)->enc_hw_tx_insert_vlan_enabled)
 1511                 max_descs++;
 1512 
 1513         if (type == SFXGE_TXQ_IP_TCP_UDP_CKSUM) {
 1514                 /*
 1515                  * Plus header and payload descriptor for each output segment.
 1516                  * Minus one since header fragment is already counted.
 1517                  * Even if FATSO is used, we should be ready to fallback
 1518                  * to do it in the driver.
 1519                  */
 1520                 sw_tso_max_descs = SFXGE_TSO_MAX_SEGS * 2 - 1;
 1521 
 1522                 /* FW assisted TSOv1 requires one more descriptor per segment
 1523                  * in comparison to SW TSO */
 1524                 if (tso_fw_assisted & SFXGE_FATSOV1)
 1525                         fa_tso_v1_max_descs =
 1526                             sw_tso_max_descs + SFXGE_TSO_MAX_SEGS;
 1527 
 1528                 /* FW assisted TSOv2 requires 3 (2 FATSO plus header) extra
 1529                  * descriptors per superframe limited by number of DMA fetches
 1530                  * per packet. The first packet header is already counted.
 1531                  */
 1532                 if (tso_fw_assisted & SFXGE_FATSOV2) {
 1533                         fa_tso_v2_max_descs =
 1534                             howmany(SFXGE_TX_MAPPING_MAX_SEG,
 1535                                     EFX_TX_FATSOV2_DMA_SEGS_PER_PKT_MAX - 1) *
 1536                             (EFX_TX_FATSOV2_OPT_NDESCS + 1) - 1;
 1537                 }
 1538 
 1539                 max_descs += MAX(sw_tso_max_descs,
 1540                                  MAX(fa_tso_v1_max_descs, fa_tso_v2_max_descs));
 1541         }
 1542 
 1543         return (max_descs);
 1544 }
 1545 
 1546 static int
 1547 sfxge_tx_qstart(struct sfxge_softc *sc, unsigned int index)
 1548 {
 1549         struct sfxge_txq *txq;
 1550         efsys_mem_t *esmp;
 1551         uint16_t flags;
 1552         unsigned int tso_fw_assisted;
 1553         struct sfxge_evq *evq;
 1554         unsigned int desc_index;
 1555         int rc;
 1556 
 1557         SFXGE_ADAPTER_LOCK_ASSERT_OWNED(sc);
 1558 
 1559         txq = sc->txq[index];
 1560         esmp = &txq->mem;
 1561         evq = sc->evq[txq->evq_index];
 1562 
 1563         KASSERT(txq->init_state == SFXGE_TXQ_INITIALIZED,
 1564             ("txq->init_state != SFXGE_TXQ_INITIALIZED"));
 1565         KASSERT(evq->init_state == SFXGE_EVQ_STARTED,
 1566             ("evq->init_state != SFXGE_EVQ_STARTED"));
 1567 
 1568         /* Program the buffer table. */
 1569         if ((rc = efx_sram_buf_tbl_set(sc->enp, txq->buf_base_id, esmp,
 1570             EFX_TXQ_NBUFS(sc->txq_entries))) != 0)
 1571                 return (rc);
 1572 
 1573         /* Determine the kind of queue we are creating. */
 1574         tso_fw_assisted = 0;
 1575         switch (txq->type) {
 1576         case SFXGE_TXQ_NON_CKSUM:
 1577                 flags = 0;
 1578                 break;
 1579         case SFXGE_TXQ_IP_CKSUM:
 1580                 flags = EFX_TXQ_CKSUM_IPV4;
 1581                 break;
 1582         case SFXGE_TXQ_IP_TCP_UDP_CKSUM:
 1583                 flags = EFX_TXQ_CKSUM_IPV4 | EFX_TXQ_CKSUM_TCPUDP;
 1584                 tso_fw_assisted = sc->tso_fw_assisted;
 1585                 if (tso_fw_assisted & SFXGE_FATSOV2)
 1586                         flags |= EFX_TXQ_FATSOV2;
 1587                 break;
 1588         default:
 1589                 KASSERT(0, ("Impossible TX queue"));
 1590                 flags = 0;
 1591                 break;
 1592         }
 1593 
 1594         /* Create the common code transmit queue. */
 1595         if ((rc = efx_tx_qcreate(sc->enp, index, txq->type, esmp,
 1596             sc->txq_entries, txq->buf_base_id, flags, evq->common,
 1597             &txq->common, &desc_index)) != 0) {
 1598                 /* Retry if no FATSOv2 resources, otherwise fail */
 1599                 if ((rc != ENOSPC) || (~flags & EFX_TXQ_FATSOV2))
 1600                         goto fail;
 1601 
 1602                 /* Looks like all FATSOv2 contexts are used */
 1603                 flags &= ~EFX_TXQ_FATSOV2;
 1604                 tso_fw_assisted &= ~SFXGE_FATSOV2;
 1605                 if ((rc = efx_tx_qcreate(sc->enp, index, txq->type, esmp,
 1606                     sc->txq_entries, txq->buf_base_id, flags, evq->common,
 1607                     &txq->common, &desc_index)) != 0)
 1608                         goto fail;
 1609         }
 1610 
 1611         /* Initialise queue descriptor indexes */
 1612         txq->added = txq->pending = txq->completed = txq->reaped = desc_index;
 1613 
 1614         SFXGE_TXQ_LOCK(txq);
 1615 
 1616         /* Enable the transmit queue. */
 1617         efx_tx_qenable(txq->common);
 1618 
 1619         txq->init_state = SFXGE_TXQ_STARTED;
 1620         txq->flush_state = SFXGE_FLUSH_REQUIRED;
 1621         txq->tso_fw_assisted = tso_fw_assisted;
 1622 
 1623         txq->max_pkt_desc = sfxge_tx_max_pkt_desc(sc, txq->type,
 1624                                                   tso_fw_assisted);
 1625 
 1626         SFXGE_TXQ_UNLOCK(txq);
 1627 
 1628         return (0);
 1629 
 1630 fail:
 1631         efx_sram_buf_tbl_clear(sc->enp, txq->buf_base_id,
 1632             EFX_TXQ_NBUFS(sc->txq_entries));
 1633         return (rc);
 1634 }
 1635 
 1636 void
 1637 sfxge_tx_stop(struct sfxge_softc *sc)
 1638 {
 1639         int index;
 1640 
 1641         index = sc->txq_count;
 1642         while (--index >= 0)
 1643                 sfxge_tx_qstop(sc, index);
 1644 
 1645         /* Tear down the transmit module */
 1646         efx_tx_fini(sc->enp);
 1647 }
 1648 
 1649 int
 1650 sfxge_tx_start(struct sfxge_softc *sc)
 1651 {
 1652         int index;
 1653         int rc;
 1654 
 1655         /* Initialize the common code transmit module. */
 1656         if ((rc = efx_tx_init(sc->enp)) != 0)
 1657                 return (rc);
 1658 
 1659         for (index = 0; index < sc->txq_count; index++) {
 1660                 if ((rc = sfxge_tx_qstart(sc, index)) != 0)
 1661                         goto fail;
 1662         }
 1663 
 1664         return (0);
 1665 
 1666 fail:
 1667         while (--index >= 0)
 1668                 sfxge_tx_qstop(sc, index);
 1669 
 1670         efx_tx_fini(sc->enp);
 1671 
 1672         return (rc);
 1673 }
 1674 
 1675 static int
 1676 sfxge_txq_stat_init(struct sfxge_txq *txq, struct sysctl_oid *txq_node)
 1677 {
 1678         struct sysctl_ctx_list *ctx = device_get_sysctl_ctx(txq->sc->dev);
 1679         struct sysctl_oid *stat_node;
 1680         unsigned int id;
 1681 
 1682         stat_node = SYSCTL_ADD_NODE(ctx, SYSCTL_CHILDREN(txq_node), OID_AUTO,
 1683                                     "stats", CTLFLAG_RD, NULL,
 1684                                     "Tx queue statistics");
 1685         if (stat_node == NULL)
 1686                 return (ENOMEM);
 1687 
 1688         for (id = 0; id < nitems(sfxge_tx_stats); id++) {
 1689                 SYSCTL_ADD_ULONG(
 1690                     ctx, SYSCTL_CHILDREN(stat_node), OID_AUTO,
 1691                     sfxge_tx_stats[id].name, CTLFLAG_RD | CTLFLAG_STATS,
 1692                     (unsigned long *)((caddr_t)txq + sfxge_tx_stats[id].offset),
 1693                     "");
 1694         }
 1695 
 1696         return (0);
 1697 }
 1698 
 1699 /**
 1700  * Destroy a transmit queue.
 1701  */
 1702 static void
 1703 sfxge_tx_qfini(struct sfxge_softc *sc, unsigned int index)
 1704 {
 1705         struct sfxge_txq *txq;
 1706         unsigned int nmaps;
 1707 
 1708         txq = sc->txq[index];
 1709 
 1710         KASSERT(txq->init_state == SFXGE_TXQ_INITIALIZED,
 1711             ("txq->init_state != SFXGE_TXQ_INITIALIZED"));
 1712 
 1713         if (txq->type == SFXGE_TXQ_IP_TCP_UDP_CKSUM)
 1714                 tso_fini(txq);
 1715 
 1716         /* Free the context arrays. */
 1717         free(txq->pend_desc, M_SFXGE);
 1718         nmaps = sc->txq_entries;
 1719         while (nmaps-- != 0)
 1720                 bus_dmamap_destroy(txq->packet_dma_tag, txq->stmp[nmaps].map);
 1721         free(txq->stmp, M_SFXGE);
 1722 
 1723         /* Release DMA memory mapping. */
 1724         sfxge_dma_free(&txq->mem);
 1725 
 1726         sc->txq[index] = NULL;
 1727 
 1728         SFXGE_TXQ_LOCK_DESTROY(txq);
 1729 
 1730         free(txq, M_SFXGE);
 1731 }
 1732 
 1733 static int
 1734 sfxge_tx_qinit(struct sfxge_softc *sc, unsigned int txq_index,
 1735                enum sfxge_txq_type type, unsigned int evq_index)
 1736 {
 1737         const efx_nic_cfg_t *encp = efx_nic_cfg_get(sc->enp);
 1738         char name[16];
 1739         struct sysctl_ctx_list *ctx = device_get_sysctl_ctx(sc->dev);
 1740         struct sysctl_oid *txq_node;
 1741         struct sfxge_txq *txq;
 1742         struct sfxge_evq *evq;
 1743         struct sfxge_tx_dpl *stdp;
 1744         struct sysctl_oid *dpl_node;
 1745         efsys_mem_t *esmp;
 1746         unsigned int nmaps;
 1747         int rc;
 1748 
 1749         txq = malloc(sizeof(struct sfxge_txq), M_SFXGE, M_ZERO | M_WAITOK);
 1750         txq->sc = sc;
 1751         txq->entries = sc->txq_entries;
 1752         txq->ptr_mask = txq->entries - 1;
 1753 
 1754         sc->txq[txq_index] = txq;
 1755         esmp = &txq->mem;
 1756 
 1757         evq = sc->evq[evq_index];
 1758 
 1759         /* Allocate and zero DMA space for the descriptor ring. */
 1760         if ((rc = sfxge_dma_alloc(sc, EFX_TXQ_SIZE(sc->txq_entries), esmp)) != 0)
 1761                 return (rc);
 1762 
 1763         /* Allocate buffer table entries. */
 1764         sfxge_sram_buf_tbl_alloc(sc, EFX_TXQ_NBUFS(sc->txq_entries),
 1765                                  &txq->buf_base_id);
 1766 
 1767         /* Create a DMA tag for packet mappings. */
 1768         if (bus_dma_tag_create(sc->parent_dma_tag, 1,
 1769             encp->enc_tx_dma_desc_boundary,
 1770             MIN(0x3FFFFFFFFFFFUL, BUS_SPACE_MAXADDR), BUS_SPACE_MAXADDR, NULL,
 1771             NULL, 0x11000, SFXGE_TX_MAPPING_MAX_SEG,
 1772             encp->enc_tx_dma_desc_size_max, 0, NULL, NULL,
 1773             &txq->packet_dma_tag) != 0) {
 1774                 device_printf(sc->dev, "Couldn't allocate txq DMA tag\n");
 1775                 rc = ENOMEM;
 1776                 goto fail;
 1777         }
 1778 
 1779         /* Allocate pending descriptor array for batching writes. */
 1780         txq->pend_desc = malloc(sizeof(efx_desc_t) * sc->txq_entries,
 1781                                 M_SFXGE, M_ZERO | M_WAITOK);
 1782 
 1783         /* Allocate and initialise mbuf DMA mapping array. */
 1784         txq->stmp = malloc(sizeof(struct sfxge_tx_mapping) * sc->txq_entries,
 1785             M_SFXGE, M_ZERO | M_WAITOK);
 1786         for (nmaps = 0; nmaps < sc->txq_entries; nmaps++) {
 1787                 rc = bus_dmamap_create(txq->packet_dma_tag, 0,
 1788                                        &txq->stmp[nmaps].map);
 1789                 if (rc != 0)
 1790                         goto fail2;
 1791         }
 1792 
 1793         snprintf(name, sizeof(name), "%u", txq_index);
 1794         txq_node = SYSCTL_ADD_NODE(ctx, SYSCTL_CHILDREN(sc->txqs_node),
 1795                                    OID_AUTO, name, CTLFLAG_RD, NULL, "");
 1796         if (txq_node == NULL) {
 1797                 rc = ENOMEM;
 1798                 goto fail_txq_node;
 1799         }
 1800 
 1801         if (type == SFXGE_TXQ_IP_TCP_UDP_CKSUM &&
 1802             (rc = tso_init(txq)) != 0)
 1803                 goto fail3;
 1804 
 1805         /* Initialize the deferred packet list. */
 1806         stdp = &txq->dpl;
 1807         stdp->std_put_max = sfxge_tx_dpl_put_max;
 1808         stdp->std_get_max = sfxge_tx_dpl_get_max;
 1809         stdp->std_get_non_tcp_max = sfxge_tx_dpl_get_non_tcp_max;
 1810         stdp->std_getp = &stdp->std_get;
 1811 
 1812         SFXGE_TXQ_LOCK_INIT(txq, device_get_nameunit(sc->dev), txq_index);
 1813 
 1814         dpl_node = SYSCTL_ADD_NODE(ctx, SYSCTL_CHILDREN(txq_node), OID_AUTO,
 1815                                    "dpl", CTLFLAG_RD, NULL,
 1816                                    "Deferred packet list statistics");
 1817         if (dpl_node == NULL) {
 1818                 rc = ENOMEM;
 1819                 goto fail_dpl_node;
 1820         }
 1821 
 1822         SYSCTL_ADD_UINT(ctx, SYSCTL_CHILDREN(dpl_node), OID_AUTO,
 1823                         "get_count", CTLFLAG_RD | CTLFLAG_STATS,
 1824                         &stdp->std_get_count, 0, "");
 1825         SYSCTL_ADD_UINT(ctx, SYSCTL_CHILDREN(dpl_node), OID_AUTO,
 1826                         "get_non_tcp_count", CTLFLAG_RD | CTLFLAG_STATS,
 1827                         &stdp->std_get_non_tcp_count, 0, "");
 1828         SYSCTL_ADD_UINT(ctx, SYSCTL_CHILDREN(dpl_node), OID_AUTO,
 1829                         "get_hiwat", CTLFLAG_RD | CTLFLAG_STATS,
 1830                         &stdp->std_get_hiwat, 0, "");
 1831         SYSCTL_ADD_UINT(ctx, SYSCTL_CHILDREN(dpl_node), OID_AUTO,
 1832                         "put_hiwat", CTLFLAG_RD | CTLFLAG_STATS,
 1833                         &stdp->std_put_hiwat, 0, "");
 1834 
 1835         rc = sfxge_txq_stat_init(txq, txq_node);
 1836         if (rc != 0)
 1837                 goto fail_txq_stat_init;
 1838 
 1839         txq->type = type;
 1840         txq->evq_index = evq_index;
 1841         txq->txq_index = txq_index;
 1842         txq->init_state = SFXGE_TXQ_INITIALIZED;
 1843         txq->hw_vlan_tci = 0;
 1844 
 1845         return (0);
 1846 
 1847 fail_txq_stat_init:
 1848 fail_dpl_node:
 1849 fail3:
 1850 fail_txq_node:
 1851         free(txq->pend_desc, M_SFXGE);
 1852 fail2:
 1853         while (nmaps-- != 0)
 1854                 bus_dmamap_destroy(txq->packet_dma_tag, txq->stmp[nmaps].map);
 1855         free(txq->stmp, M_SFXGE);
 1856         bus_dma_tag_destroy(txq->packet_dma_tag);
 1857 
 1858 fail:
 1859         sfxge_dma_free(esmp);
 1860 
 1861         return (rc);
 1862 }
 1863 
 1864 static int
 1865 sfxge_tx_stat_handler(SYSCTL_HANDLER_ARGS)
 1866 {
 1867         struct sfxge_softc *sc = arg1;
 1868         unsigned int id = arg2;
 1869         unsigned long sum;
 1870         unsigned int index;
 1871 
 1872         /* Sum across all TX queues */
 1873         sum = 0;
 1874         for (index = 0; index < sc->txq_count; index++)
 1875                 sum += *(unsigned long *)((caddr_t)sc->txq[index] +
 1876                                           sfxge_tx_stats[id].offset);
 1877 
 1878         return (SYSCTL_OUT(req, &sum, sizeof(sum)));
 1879 }
 1880 
 1881 static void
 1882 sfxge_tx_stat_init(struct sfxge_softc *sc)
 1883 {
 1884         struct sysctl_ctx_list *ctx = device_get_sysctl_ctx(sc->dev);
 1885         struct sysctl_oid_list *stat_list;
 1886         unsigned int id;
 1887 
 1888         stat_list = SYSCTL_CHILDREN(sc->stats_node);
 1889 
 1890         for (id = 0; id < nitems(sfxge_tx_stats); id++) {
 1891                 SYSCTL_ADD_PROC(
 1892                         ctx, stat_list,
 1893                         OID_AUTO, sfxge_tx_stats[id].name,
 1894                         CTLTYPE_ULONG|CTLFLAG_RD,
 1895                         sc, id, sfxge_tx_stat_handler, "LU",
 1896                         "");
 1897         }
 1898 }
 1899 
 1900 uint64_t
 1901 sfxge_tx_get_drops(struct sfxge_softc *sc)
 1902 {
 1903         unsigned int index;
 1904         uint64_t drops = 0;
 1905         struct sfxge_txq *txq;
 1906 
 1907         /* Sum across all TX queues */
 1908         for (index = 0; index < sc->txq_count; index++) {
 1909                 txq = sc->txq[index];
 1910                 /*
 1911                  * In theory, txq->put_overflow and txq->netdown_drops
 1912                  * should use atomic operation and other should be
 1913                  * obtained under txq lock, but it is just statistics.
 1914                  */
 1915                 drops += txq->drops + txq->get_overflow +
 1916                          txq->get_non_tcp_overflow +
 1917                          txq->put_overflow + txq->netdown_drops +
 1918                          txq->tso_pdrop_too_many + txq->tso_pdrop_no_rsrc;
 1919         }
 1920         return (drops);
 1921 }
 1922 
 1923 void
 1924 sfxge_tx_fini(struct sfxge_softc *sc)
 1925 {
 1926         int index;
 1927 
 1928         index = sc->txq_count;
 1929         while (--index >= 0)
 1930                 sfxge_tx_qfini(sc, index);
 1931 
 1932         sc->txq_count = 0;
 1933 }
 1934 
 1935 
 1936 int
 1937 sfxge_tx_init(struct sfxge_softc *sc)
 1938 {
 1939         const efx_nic_cfg_t *encp = efx_nic_cfg_get(sc->enp);
 1940         struct sfxge_intr *intr;
 1941         int index;
 1942         int rc;
 1943 
 1944         intr = &sc->intr;
 1945 
 1946         KASSERT(intr->state == SFXGE_INTR_INITIALIZED,
 1947             ("intr->state != SFXGE_INTR_INITIALIZED"));
 1948 
 1949         if (sfxge_tx_dpl_get_max <= 0) {
 1950                 log(LOG_ERR, "%s=%d must be greater than 0",
 1951                     SFXGE_PARAM_TX_DPL_GET_MAX, sfxge_tx_dpl_get_max);
 1952                 rc = EINVAL;
 1953                 goto fail_tx_dpl_get_max;
 1954         }
 1955         if (sfxge_tx_dpl_get_non_tcp_max <= 0) {
 1956                 log(LOG_ERR, "%s=%d must be greater than 0",
 1957                     SFXGE_PARAM_TX_DPL_GET_NON_TCP_MAX,
 1958                     sfxge_tx_dpl_get_non_tcp_max);
 1959                 rc = EINVAL;
 1960                 goto fail_tx_dpl_get_non_tcp_max;
 1961         }
 1962         if (sfxge_tx_dpl_put_max < 0) {
 1963                 log(LOG_ERR, "%s=%d must be greater or equal to 0",
 1964                     SFXGE_PARAM_TX_DPL_PUT_MAX, sfxge_tx_dpl_put_max);
 1965                 rc = EINVAL;
 1966                 goto fail_tx_dpl_put_max;
 1967         }
 1968 
 1969         sc->txq_count = SFXGE_TXQ_NTYPES - 1 + sc->intr.n_alloc;
 1970 
 1971         sc->tso_fw_assisted = sfxge_tso_fw_assisted;
 1972         if ((~encp->enc_features & EFX_FEATURE_FW_ASSISTED_TSO) ||
 1973             (!encp->enc_fw_assisted_tso_enabled))
 1974                 sc->tso_fw_assisted &= ~SFXGE_FATSOV1;
 1975         if ((~encp->enc_features & EFX_FEATURE_FW_ASSISTED_TSO_V2) ||
 1976             (!encp->enc_fw_assisted_tso_v2_enabled))
 1977                 sc->tso_fw_assisted &= ~SFXGE_FATSOV2;
 1978 
 1979         sc->txqs_node = SYSCTL_ADD_NODE(
 1980                 device_get_sysctl_ctx(sc->dev),
 1981                 SYSCTL_CHILDREN(device_get_sysctl_tree(sc->dev)),
 1982                 OID_AUTO, "txq", CTLFLAG_RD, NULL, "Tx queues");
 1983         if (sc->txqs_node == NULL) {
 1984                 rc = ENOMEM;
 1985                 goto fail_txq_node;
 1986         }
 1987 
 1988         /* Initialize the transmit queues */
 1989         if ((rc = sfxge_tx_qinit(sc, SFXGE_TXQ_NON_CKSUM,
 1990             SFXGE_TXQ_NON_CKSUM, 0)) != 0)
 1991                 goto fail;
 1992 
 1993         if ((rc = sfxge_tx_qinit(sc, SFXGE_TXQ_IP_CKSUM,
 1994             SFXGE_TXQ_IP_CKSUM, 0)) != 0)
 1995                 goto fail2;
 1996 
 1997         for (index = 0;
 1998              index < sc->txq_count - SFXGE_TXQ_NTYPES + 1;
 1999              index++) {
 2000                 if ((rc = sfxge_tx_qinit(sc, SFXGE_TXQ_NTYPES - 1 + index,
 2001                     SFXGE_TXQ_IP_TCP_UDP_CKSUM, index)) != 0)
 2002                         goto fail3;
 2003         }
 2004 
 2005         sfxge_tx_stat_init(sc);
 2006 
 2007         return (0);
 2008 
 2009 fail3:
 2010         while (--index >= 0)
 2011                 sfxge_tx_qfini(sc, SFXGE_TXQ_IP_TCP_UDP_CKSUM + index);
 2012 
 2013         sfxge_tx_qfini(sc, SFXGE_TXQ_IP_CKSUM);
 2014 
 2015 fail2:
 2016         sfxge_tx_qfini(sc, SFXGE_TXQ_NON_CKSUM);
 2017 
 2018 fail:
 2019 fail_txq_node:
 2020         sc->txq_count = 0;
 2021 fail_tx_dpl_put_max:
 2022 fail_tx_dpl_get_non_tcp_max:
 2023 fail_tx_dpl_get_max:
 2024         return (rc);
 2025 }

Cache object: ef8629c591deb6270023e409cdeb974b


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