The Design and Implementation of the FreeBSD Operating System, Second Edition
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FreeBSD/Linux Kernel Cross Reference
sys/ofed/drivers/infiniband/core/ib_mad_rmpp.c

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    1 /*-
    2  * SPDX-License-Identifier: BSD-2-Clause OR GPL-2.0
    3  *
    4  * Copyright (c) 2005 Intel Inc. All rights reserved.
    5  * Copyright (c) 2005-2006 Voltaire, Inc. All rights reserved.
    6  * Copyright (c) 2014 Intel Corporation.  All rights reserved.
    7  *
    8  * This software is available to you under a choice of one of two
    9  * licenses.  You may choose to be licensed under the terms of the GNU
   10  * General Public License (GPL) Version 2, available from the file
   11  * COPYING in the main directory of this source tree, or the
   12  * OpenIB.org BSD license below:
   13  *
   14  *     Redistribution and use in source and binary forms, with or
   15  *     without modification, are permitted provided that the following
   16  *     conditions are met:
   17  *
   18  *      - Redistributions of source code must retain the above
   19  *        copyright notice, this list of conditions and the following
   20  *        disclaimer.
   21  *
   22  *      - Redistributions in binary form must reproduce the above
   23  *        copyright notice, this list of conditions and the following
   24  *        disclaimer in the documentation and/or other materials
   25  *        provided with the distribution.
   26  *
   27  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
   28  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
   29  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
   30  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
   31  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
   32  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
   33  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
   34  * SOFTWARE.
   35  */
   36 
   37 #include <sys/cdefs.h>
   38 __FBSDID("$FreeBSD$");
   39 
   40 #include <linux/slab.h>
   41 
   42 #include "mad_priv.h"
   43 #include "mad_rmpp.h"
   44 
   45 enum rmpp_state {
   46         RMPP_STATE_ACTIVE,
   47         RMPP_STATE_TIMEOUT,
   48         RMPP_STATE_COMPLETE,
   49         RMPP_STATE_CANCELING
   50 };
   51 
   52 struct mad_rmpp_recv {
   53         struct ib_mad_agent_private *agent;
   54         struct list_head list;
   55         struct delayed_work timeout_work;
   56         struct delayed_work cleanup_work;
   57         struct completion comp;
   58         enum rmpp_state state;
   59         spinlock_t lock;
   60         atomic_t refcount;
   61 
   62         struct ib_ah *ah;
   63         struct ib_mad_recv_wc *rmpp_wc;
   64         struct ib_mad_recv_buf *cur_seg_buf;
   65         int last_ack;
   66         int seg_num;
   67         int newwin;
   68         int repwin;
   69 
   70         __be64 tid;
   71         u32 src_qp;
   72         u16 slid;
   73         u8 mgmt_class;
   74         u8 class_version;
   75         u8 method;
   76         u8 base_version;
   77 };
   78 
   79 static inline void deref_rmpp_recv(struct mad_rmpp_recv *rmpp_recv)
   80 {
   81         if (atomic_dec_and_test(&rmpp_recv->refcount))
   82                 complete(&rmpp_recv->comp);
   83 }
   84 
   85 static void destroy_rmpp_recv(struct mad_rmpp_recv *rmpp_recv)
   86 {
   87         deref_rmpp_recv(rmpp_recv);
   88         wait_for_completion(&rmpp_recv->comp);
   89         ib_destroy_ah(rmpp_recv->ah, RDMA_DESTROY_AH_SLEEPABLE);
   90         kfree(rmpp_recv);
   91 }
   92 
   93 void ib_cancel_rmpp_recvs(struct ib_mad_agent_private *agent)
   94 {
   95         struct mad_rmpp_recv *rmpp_recv, *temp_rmpp_recv;
   96         unsigned long flags;
   97 
   98         spin_lock_irqsave(&agent->lock, flags);
   99         list_for_each_entry(rmpp_recv, &agent->rmpp_list, list) {
  100                 if (rmpp_recv->state != RMPP_STATE_COMPLETE)
  101                         ib_free_recv_mad(rmpp_recv->rmpp_wc);
  102                 rmpp_recv->state = RMPP_STATE_CANCELING;
  103         }
  104         spin_unlock_irqrestore(&agent->lock, flags);
  105 
  106         list_for_each_entry(rmpp_recv, &agent->rmpp_list, list) {
  107                 cancel_delayed_work_sync(&rmpp_recv->timeout_work);
  108                 cancel_delayed_work_sync(&rmpp_recv->cleanup_work);
  109         }
  110 
  111         flush_workqueue(agent->qp_info->port_priv->wq);
  112 
  113         list_for_each_entry_safe(rmpp_recv, temp_rmpp_recv,
  114                                  &agent->rmpp_list, list) {
  115                 list_del(&rmpp_recv->list);
  116                 destroy_rmpp_recv(rmpp_recv);
  117         }
  118 }
  119 
  120 static void format_ack(struct ib_mad_send_buf *msg,
  121                        struct ib_rmpp_mad *data,
  122                        struct mad_rmpp_recv *rmpp_recv)
  123 {
  124         struct ib_rmpp_mad *ack = msg->mad;
  125         unsigned long flags;
  126 
  127         memcpy(ack, &data->mad_hdr, msg->hdr_len);
  128 
  129         ack->mad_hdr.method ^= IB_MGMT_METHOD_RESP;
  130         ack->rmpp_hdr.rmpp_type = IB_MGMT_RMPP_TYPE_ACK;
  131         ib_set_rmpp_flags(&ack->rmpp_hdr, IB_MGMT_RMPP_FLAG_ACTIVE);
  132 
  133         spin_lock_irqsave(&rmpp_recv->lock, flags);
  134         rmpp_recv->last_ack = rmpp_recv->seg_num;
  135         ack->rmpp_hdr.seg_num = cpu_to_be32(rmpp_recv->seg_num);
  136         ack->rmpp_hdr.paylen_newwin = cpu_to_be32(rmpp_recv->newwin);
  137         spin_unlock_irqrestore(&rmpp_recv->lock, flags);
  138 }
  139 
  140 static void ack_recv(struct mad_rmpp_recv *rmpp_recv,
  141                      struct ib_mad_recv_wc *recv_wc)
  142 {
  143         struct ib_mad_send_buf *msg;
  144         int ret, hdr_len;
  145 
  146         hdr_len = ib_get_mad_data_offset(recv_wc->recv_buf.mad->mad_hdr.mgmt_class);
  147         msg = ib_create_send_mad(&rmpp_recv->agent->agent, recv_wc->wc->src_qp,
  148                                  recv_wc->wc->pkey_index, 1, hdr_len,
  149                                  0, GFP_KERNEL,
  150                                  IB_MGMT_BASE_VERSION);
  151         if (IS_ERR(msg))
  152                 return;
  153 
  154         format_ack(msg, (struct ib_rmpp_mad *) recv_wc->recv_buf.mad, rmpp_recv);
  155         msg->ah = rmpp_recv->ah;
  156         ret = ib_post_send_mad(msg, NULL);
  157         if (ret)
  158                 ib_free_send_mad(msg);
  159 }
  160 
  161 static struct ib_mad_send_buf *alloc_response_msg(struct ib_mad_agent *agent,
  162                                                   struct ib_mad_recv_wc *recv_wc)
  163 {
  164         struct ib_mad_send_buf *msg;
  165         struct ib_ah *ah;
  166         int hdr_len;
  167 
  168         ah = ib_create_ah_from_wc(agent->qp->pd, recv_wc->wc,
  169                                   recv_wc->recv_buf.grh, agent->port_num);
  170         if (IS_ERR(ah))
  171                 return (void *) ah;
  172 
  173         hdr_len = ib_get_mad_data_offset(recv_wc->recv_buf.mad->mad_hdr.mgmt_class);
  174         msg = ib_create_send_mad(agent, recv_wc->wc->src_qp,
  175                                  recv_wc->wc->pkey_index, 1,
  176                                  hdr_len, 0, GFP_KERNEL,
  177                                  IB_MGMT_BASE_VERSION);
  178         if (IS_ERR(msg))
  179                 ib_destroy_ah(ah, RDMA_DESTROY_AH_SLEEPABLE);
  180         else {
  181                 msg->ah = ah;
  182                 msg->context[0] = ah;
  183         }
  184 
  185         return msg;
  186 }
  187 
  188 static void ack_ds_ack(struct ib_mad_agent_private *agent,
  189                        struct ib_mad_recv_wc *recv_wc)
  190 {
  191         struct ib_mad_send_buf *msg;
  192         struct ib_rmpp_mad *rmpp_mad;
  193         int ret;
  194 
  195         msg = alloc_response_msg(&agent->agent, recv_wc);
  196         if (IS_ERR(msg))
  197                 return;
  198 
  199         rmpp_mad = msg->mad;
  200         memcpy(rmpp_mad, recv_wc->recv_buf.mad, msg->hdr_len);
  201 
  202         rmpp_mad->mad_hdr.method ^= IB_MGMT_METHOD_RESP;
  203         ib_set_rmpp_flags(&rmpp_mad->rmpp_hdr, IB_MGMT_RMPP_FLAG_ACTIVE);
  204         rmpp_mad->rmpp_hdr.seg_num = 0;
  205         rmpp_mad->rmpp_hdr.paylen_newwin = cpu_to_be32(1);
  206 
  207         ret = ib_post_send_mad(msg, NULL);
  208         if (ret) {
  209                 ib_destroy_ah(msg->ah, RDMA_DESTROY_AH_SLEEPABLE);
  210                 ib_free_send_mad(msg);
  211         }
  212 }
  213 
  214 void ib_rmpp_send_handler(struct ib_mad_send_wc *mad_send_wc)
  215 {
  216         if (mad_send_wc->send_buf->context[0] == mad_send_wc->send_buf->ah)
  217                 ib_destroy_ah(mad_send_wc->send_buf->ah, RDMA_DESTROY_AH_SLEEPABLE);
  218         ib_free_send_mad(mad_send_wc->send_buf);
  219 }
  220 
  221 static void nack_recv(struct ib_mad_agent_private *agent,
  222                       struct ib_mad_recv_wc *recv_wc, u8 rmpp_status)
  223 {
  224         struct ib_mad_send_buf *msg;
  225         struct ib_rmpp_mad *rmpp_mad;
  226         int ret;
  227 
  228         msg = alloc_response_msg(&agent->agent, recv_wc);
  229         if (IS_ERR(msg))
  230                 return;
  231 
  232         rmpp_mad = msg->mad;
  233         memcpy(rmpp_mad, recv_wc->recv_buf.mad, msg->hdr_len);
  234 
  235         rmpp_mad->mad_hdr.method ^= IB_MGMT_METHOD_RESP;
  236         rmpp_mad->rmpp_hdr.rmpp_version = IB_MGMT_RMPP_VERSION;
  237         rmpp_mad->rmpp_hdr.rmpp_type = IB_MGMT_RMPP_TYPE_ABORT;
  238         ib_set_rmpp_flags(&rmpp_mad->rmpp_hdr, IB_MGMT_RMPP_FLAG_ACTIVE);
  239         rmpp_mad->rmpp_hdr.rmpp_status = rmpp_status;
  240         rmpp_mad->rmpp_hdr.seg_num = 0;
  241         rmpp_mad->rmpp_hdr.paylen_newwin = 0;
  242 
  243         ret = ib_post_send_mad(msg, NULL);
  244         if (ret) {
  245                 ib_destroy_ah(msg->ah, RDMA_DESTROY_AH_SLEEPABLE);
  246                 ib_free_send_mad(msg);
  247         }
  248 }
  249 
  250 static void recv_timeout_handler(struct work_struct *work)
  251 {
  252         struct mad_rmpp_recv *rmpp_recv =
  253                 container_of(work, struct mad_rmpp_recv, timeout_work.work);
  254         struct ib_mad_recv_wc *rmpp_wc;
  255         unsigned long flags;
  256 
  257         spin_lock_irqsave(&rmpp_recv->agent->lock, flags);
  258         if (rmpp_recv->state != RMPP_STATE_ACTIVE) {
  259                 spin_unlock_irqrestore(&rmpp_recv->agent->lock, flags);
  260                 return;
  261         }
  262         rmpp_recv->state = RMPP_STATE_TIMEOUT;
  263         list_del(&rmpp_recv->list);
  264         spin_unlock_irqrestore(&rmpp_recv->agent->lock, flags);
  265 
  266         rmpp_wc = rmpp_recv->rmpp_wc;
  267         nack_recv(rmpp_recv->agent, rmpp_wc, IB_MGMT_RMPP_STATUS_T2L);
  268         destroy_rmpp_recv(rmpp_recv);
  269         ib_free_recv_mad(rmpp_wc);
  270 }
  271 
  272 static void recv_cleanup_handler(struct work_struct *work)
  273 {
  274         struct mad_rmpp_recv *rmpp_recv =
  275                 container_of(work, struct mad_rmpp_recv, cleanup_work.work);
  276         unsigned long flags;
  277 
  278         spin_lock_irqsave(&rmpp_recv->agent->lock, flags);
  279         if (rmpp_recv->state == RMPP_STATE_CANCELING) {
  280                 spin_unlock_irqrestore(&rmpp_recv->agent->lock, flags);
  281                 return;
  282         }
  283         list_del(&rmpp_recv->list);
  284         spin_unlock_irqrestore(&rmpp_recv->agent->lock, flags);
  285         destroy_rmpp_recv(rmpp_recv);
  286 }
  287 
  288 static struct mad_rmpp_recv *
  289 create_rmpp_recv(struct ib_mad_agent_private *agent,
  290                  struct ib_mad_recv_wc *mad_recv_wc)
  291 {
  292         struct mad_rmpp_recv *rmpp_recv;
  293         struct ib_mad_hdr *mad_hdr;
  294 
  295         rmpp_recv = kmalloc(sizeof *rmpp_recv, GFP_KERNEL);
  296         if (!rmpp_recv)
  297                 return NULL;
  298 
  299         rmpp_recv->ah = ib_create_ah_from_wc(agent->agent.qp->pd,
  300                                              mad_recv_wc->wc,
  301                                              mad_recv_wc->recv_buf.grh,
  302                                              agent->agent.port_num);
  303         if (IS_ERR(rmpp_recv->ah))
  304                 goto error;
  305 
  306         rmpp_recv->agent = agent;
  307         init_completion(&rmpp_recv->comp);
  308         INIT_DELAYED_WORK(&rmpp_recv->timeout_work, recv_timeout_handler);
  309         INIT_DELAYED_WORK(&rmpp_recv->cleanup_work, recv_cleanup_handler);
  310         spin_lock_init(&rmpp_recv->lock);
  311         rmpp_recv->state = RMPP_STATE_ACTIVE;
  312         atomic_set(&rmpp_recv->refcount, 1);
  313 
  314         rmpp_recv->rmpp_wc = mad_recv_wc;
  315         rmpp_recv->cur_seg_buf = &mad_recv_wc->recv_buf;
  316         rmpp_recv->newwin = 1;
  317         rmpp_recv->seg_num = 1;
  318         rmpp_recv->last_ack = 0;
  319         rmpp_recv->repwin = 1;
  320 
  321         mad_hdr = &mad_recv_wc->recv_buf.mad->mad_hdr;
  322         rmpp_recv->tid = mad_hdr->tid;
  323         rmpp_recv->src_qp = mad_recv_wc->wc->src_qp;
  324         rmpp_recv->slid = mad_recv_wc->wc->slid;
  325         rmpp_recv->mgmt_class = mad_hdr->mgmt_class;
  326         rmpp_recv->class_version = mad_hdr->class_version;
  327         rmpp_recv->method  = mad_hdr->method;
  328         rmpp_recv->base_version  = mad_hdr->base_version;
  329         return rmpp_recv;
  330 
  331 error:  kfree(rmpp_recv);
  332         return NULL;
  333 }
  334 
  335 static struct mad_rmpp_recv *
  336 find_rmpp_recv(struct ib_mad_agent_private *agent,
  337                struct ib_mad_recv_wc *mad_recv_wc)
  338 {
  339         struct mad_rmpp_recv *rmpp_recv;
  340         struct ib_mad_hdr *mad_hdr = &mad_recv_wc->recv_buf.mad->mad_hdr;
  341 
  342         list_for_each_entry(rmpp_recv, &agent->rmpp_list, list) {
  343                 if (rmpp_recv->tid == mad_hdr->tid &&
  344                     rmpp_recv->src_qp == mad_recv_wc->wc->src_qp &&
  345                     rmpp_recv->slid == mad_recv_wc->wc->slid &&
  346                     rmpp_recv->mgmt_class == mad_hdr->mgmt_class &&
  347                     rmpp_recv->class_version == mad_hdr->class_version &&
  348                     rmpp_recv->method == mad_hdr->method)
  349                         return rmpp_recv;
  350         }
  351         return NULL;
  352 }
  353 
  354 static struct mad_rmpp_recv *
  355 acquire_rmpp_recv(struct ib_mad_agent_private *agent,
  356                   struct ib_mad_recv_wc *mad_recv_wc)
  357 {
  358         struct mad_rmpp_recv *rmpp_recv;
  359         unsigned long flags;
  360 
  361         spin_lock_irqsave(&agent->lock, flags);
  362         rmpp_recv = find_rmpp_recv(agent, mad_recv_wc);
  363         if (rmpp_recv)
  364                 atomic_inc(&rmpp_recv->refcount);
  365         spin_unlock_irqrestore(&agent->lock, flags);
  366         return rmpp_recv;
  367 }
  368 
  369 static struct mad_rmpp_recv *
  370 insert_rmpp_recv(struct ib_mad_agent_private *agent,
  371                  struct mad_rmpp_recv *rmpp_recv)
  372 {
  373         struct mad_rmpp_recv *cur_rmpp_recv;
  374 
  375         cur_rmpp_recv = find_rmpp_recv(agent, rmpp_recv->rmpp_wc);
  376         if (!cur_rmpp_recv)
  377                 list_add_tail(&rmpp_recv->list, &agent->rmpp_list);
  378 
  379         return cur_rmpp_recv;
  380 }
  381 
  382 static inline int get_last_flag(struct ib_mad_recv_buf *seg)
  383 {
  384         struct ib_rmpp_mad *rmpp_mad;
  385 
  386         rmpp_mad = (struct ib_rmpp_mad *) seg->mad;
  387         return ib_get_rmpp_flags(&rmpp_mad->rmpp_hdr) & IB_MGMT_RMPP_FLAG_LAST;
  388 }
  389 
  390 static inline int get_seg_num(struct ib_mad_recv_buf *seg)
  391 {
  392         struct ib_rmpp_mad *rmpp_mad;
  393 
  394         rmpp_mad = (struct ib_rmpp_mad *) seg->mad;
  395         return be32_to_cpu(rmpp_mad->rmpp_hdr.seg_num);
  396 }
  397 
  398 static inline struct ib_mad_recv_buf * get_next_seg(struct list_head *rmpp_list,
  399                                                     struct ib_mad_recv_buf *seg)
  400 {
  401         if (seg->list.next == rmpp_list)
  402                 return NULL;
  403 
  404         return container_of(seg->list.next, struct ib_mad_recv_buf, list);
  405 }
  406 
  407 static inline int window_size(struct ib_mad_agent_private *agent)
  408 {
  409         return max(agent->qp_info->recv_queue.max_active >> 3, 1);
  410 }
  411 
  412 static struct ib_mad_recv_buf * find_seg_location(struct list_head *rmpp_list,
  413                                                   int seg_num)
  414 {
  415         struct ib_mad_recv_buf *seg_buf;
  416         int cur_seg_num;
  417 
  418         list_for_each_entry_reverse(seg_buf, rmpp_list, list) {
  419                 cur_seg_num = get_seg_num(seg_buf);
  420                 if (seg_num > cur_seg_num)
  421                         return seg_buf;
  422                 if (seg_num == cur_seg_num)
  423                         break;
  424         }
  425         return NULL;
  426 }
  427 
  428 static void update_seg_num(struct mad_rmpp_recv *rmpp_recv,
  429                            struct ib_mad_recv_buf *new_buf)
  430 {
  431         struct list_head *rmpp_list = &rmpp_recv->rmpp_wc->rmpp_list;
  432 
  433         while (new_buf && (get_seg_num(new_buf) == rmpp_recv->seg_num + 1)) {
  434                 rmpp_recv->cur_seg_buf = new_buf;
  435                 rmpp_recv->seg_num++;
  436                 new_buf = get_next_seg(rmpp_list, new_buf);
  437         }
  438 }
  439 
  440 static inline int get_mad_len(struct mad_rmpp_recv *rmpp_recv)
  441 {
  442         struct ib_rmpp_mad *rmpp_mad;
  443         int hdr_size, data_size, pad;
  444         bool opa = rdma_cap_opa_mad(rmpp_recv->agent->qp_info->port_priv->device,
  445                                     rmpp_recv->agent->qp_info->port_priv->port_num);
  446 
  447         rmpp_mad = (struct ib_rmpp_mad *)rmpp_recv->cur_seg_buf->mad;
  448 
  449         hdr_size = ib_get_mad_data_offset(rmpp_mad->mad_hdr.mgmt_class);
  450         if (opa && rmpp_recv->base_version == OPA_MGMT_BASE_VERSION) {
  451                 data_size = sizeof(struct opa_rmpp_mad) - hdr_size;
  452                 pad = OPA_MGMT_RMPP_DATA - be32_to_cpu(rmpp_mad->rmpp_hdr.paylen_newwin);
  453                 if (pad > OPA_MGMT_RMPP_DATA || pad < 0)
  454                         pad = 0;
  455         } else {
  456                 data_size = sizeof(struct ib_rmpp_mad) - hdr_size;
  457                 pad = IB_MGMT_RMPP_DATA - be32_to_cpu(rmpp_mad->rmpp_hdr.paylen_newwin);
  458                 if (pad > IB_MGMT_RMPP_DATA || pad < 0)
  459                         pad = 0;
  460         }
  461 
  462         return hdr_size + rmpp_recv->seg_num * data_size - pad;
  463 }
  464 
  465 static struct ib_mad_recv_wc * complete_rmpp(struct mad_rmpp_recv *rmpp_recv)
  466 {
  467         struct ib_mad_recv_wc *rmpp_wc;
  468 
  469         ack_recv(rmpp_recv, rmpp_recv->rmpp_wc);
  470         if (rmpp_recv->seg_num > 1)
  471                 cancel_delayed_work(&rmpp_recv->timeout_work);
  472 
  473         rmpp_wc = rmpp_recv->rmpp_wc;
  474         rmpp_wc->mad_len = get_mad_len(rmpp_recv);
  475         /* 10 seconds until we can find the packet lifetime */
  476         queue_delayed_work(rmpp_recv->agent->qp_info->port_priv->wq,
  477                            &rmpp_recv->cleanup_work, msecs_to_jiffies(10000));
  478         return rmpp_wc;
  479 }
  480 
  481 static struct ib_mad_recv_wc *
  482 continue_rmpp(struct ib_mad_agent_private *agent,
  483               struct ib_mad_recv_wc *mad_recv_wc)
  484 {
  485         struct mad_rmpp_recv *rmpp_recv;
  486         struct ib_mad_recv_buf *prev_buf;
  487         struct ib_mad_recv_wc *done_wc;
  488         int seg_num;
  489         unsigned long flags;
  490 
  491         rmpp_recv = acquire_rmpp_recv(agent, mad_recv_wc);
  492         if (!rmpp_recv)
  493                 goto drop1;
  494 
  495         seg_num = get_seg_num(&mad_recv_wc->recv_buf);
  496 
  497         spin_lock_irqsave(&rmpp_recv->lock, flags);
  498         if ((rmpp_recv->state == RMPP_STATE_TIMEOUT) ||
  499             (seg_num > rmpp_recv->newwin))
  500                 goto drop3;
  501 
  502         if ((seg_num <= rmpp_recv->last_ack) ||
  503             (rmpp_recv->state == RMPP_STATE_COMPLETE)) {
  504                 spin_unlock_irqrestore(&rmpp_recv->lock, flags);
  505                 ack_recv(rmpp_recv, mad_recv_wc);
  506                 goto drop2;
  507         }
  508 
  509         prev_buf = find_seg_location(&rmpp_recv->rmpp_wc->rmpp_list, seg_num);
  510         if (!prev_buf)
  511                 goto drop3;
  512 
  513         done_wc = NULL;
  514         list_add(&mad_recv_wc->recv_buf.list, &prev_buf->list);
  515         if (rmpp_recv->cur_seg_buf == prev_buf) {
  516                 update_seg_num(rmpp_recv, &mad_recv_wc->recv_buf);
  517                 if (get_last_flag(rmpp_recv->cur_seg_buf)) {
  518                         rmpp_recv->state = RMPP_STATE_COMPLETE;
  519                         spin_unlock_irqrestore(&rmpp_recv->lock, flags);
  520                         done_wc = complete_rmpp(rmpp_recv);
  521                         goto out;
  522                 } else if (rmpp_recv->seg_num == rmpp_recv->newwin) {
  523                         rmpp_recv->newwin += window_size(agent);
  524                         spin_unlock_irqrestore(&rmpp_recv->lock, flags);
  525                         ack_recv(rmpp_recv, mad_recv_wc);
  526                         goto out;
  527                 }
  528         }
  529         spin_unlock_irqrestore(&rmpp_recv->lock, flags);
  530 out:
  531         deref_rmpp_recv(rmpp_recv);
  532         return done_wc;
  533 
  534 drop3:  spin_unlock_irqrestore(&rmpp_recv->lock, flags);
  535 drop2:  deref_rmpp_recv(rmpp_recv);
  536 drop1:  ib_free_recv_mad(mad_recv_wc);
  537         return NULL;
  538 }
  539 
  540 static struct ib_mad_recv_wc *
  541 start_rmpp(struct ib_mad_agent_private *agent,
  542            struct ib_mad_recv_wc *mad_recv_wc)
  543 {
  544         struct mad_rmpp_recv *rmpp_recv;
  545         unsigned long flags;
  546 
  547         rmpp_recv = create_rmpp_recv(agent, mad_recv_wc);
  548         if (!rmpp_recv) {
  549                 ib_free_recv_mad(mad_recv_wc);
  550                 return NULL;
  551         }
  552 
  553         spin_lock_irqsave(&agent->lock, flags);
  554         if (insert_rmpp_recv(agent, rmpp_recv)) {
  555                 spin_unlock_irqrestore(&agent->lock, flags);
  556                 /* duplicate first MAD */
  557                 destroy_rmpp_recv(rmpp_recv);
  558                 return continue_rmpp(agent, mad_recv_wc);
  559         }
  560         atomic_inc(&rmpp_recv->refcount);
  561 
  562         if (get_last_flag(&mad_recv_wc->recv_buf)) {
  563                 rmpp_recv->state = RMPP_STATE_COMPLETE;
  564                 spin_unlock_irqrestore(&agent->lock, flags);
  565                 complete_rmpp(rmpp_recv);
  566         } else {
  567                 spin_unlock_irqrestore(&agent->lock, flags);
  568                 /* 40 seconds until we can find the packet lifetimes */
  569                 queue_delayed_work(agent->qp_info->port_priv->wq,
  570                                    &rmpp_recv->timeout_work,
  571                                    msecs_to_jiffies(40000));
  572                 rmpp_recv->newwin += window_size(agent);
  573                 ack_recv(rmpp_recv, mad_recv_wc);
  574                 mad_recv_wc = NULL;
  575         }
  576         deref_rmpp_recv(rmpp_recv);
  577         return mad_recv_wc;
  578 }
  579 
  580 static int send_next_seg(struct ib_mad_send_wr_private *mad_send_wr)
  581 {
  582         struct ib_rmpp_mad *rmpp_mad;
  583         int timeout;
  584         u32 paylen = 0;
  585 
  586         rmpp_mad = mad_send_wr->send_buf.mad;
  587         ib_set_rmpp_flags(&rmpp_mad->rmpp_hdr, IB_MGMT_RMPP_FLAG_ACTIVE);
  588         rmpp_mad->rmpp_hdr.seg_num = cpu_to_be32(++mad_send_wr->seg_num);
  589 
  590         if (mad_send_wr->seg_num == 1) {
  591                 rmpp_mad->rmpp_hdr.rmpp_rtime_flags |= IB_MGMT_RMPP_FLAG_FIRST;
  592                 paylen = (mad_send_wr->send_buf.seg_count *
  593                           mad_send_wr->send_buf.seg_rmpp_size) -
  594                           mad_send_wr->pad;
  595         }
  596 
  597         if (mad_send_wr->seg_num == mad_send_wr->send_buf.seg_count) {
  598                 rmpp_mad->rmpp_hdr.rmpp_rtime_flags |= IB_MGMT_RMPP_FLAG_LAST;
  599                 paylen = mad_send_wr->send_buf.seg_rmpp_size - mad_send_wr->pad;
  600         }
  601         rmpp_mad->rmpp_hdr.paylen_newwin = cpu_to_be32(paylen);
  602 
  603         /* 2 seconds for an ACK until we can find the packet lifetime */
  604         timeout = mad_send_wr->send_buf.timeout_ms;
  605         if (!timeout || timeout > 2000)
  606                 mad_send_wr->timeout = msecs_to_jiffies(2000);
  607 
  608         return ib_send_mad(mad_send_wr);
  609 }
  610 
  611 static void abort_send(struct ib_mad_agent_private *agent,
  612                        struct ib_mad_recv_wc *mad_recv_wc, u8 rmpp_status)
  613 {
  614         struct ib_mad_send_wr_private *mad_send_wr;
  615         struct ib_mad_send_wc wc;
  616         unsigned long flags;
  617 
  618         spin_lock_irqsave(&agent->lock, flags);
  619         mad_send_wr = ib_find_send_mad(agent, mad_recv_wc);
  620         if (!mad_send_wr)
  621                 goto out;       /* Unmatched send */
  622 
  623         if ((mad_send_wr->last_ack == mad_send_wr->send_buf.seg_count) ||
  624             (!mad_send_wr->timeout) || (mad_send_wr->status != IB_WC_SUCCESS))
  625                 goto out;       /* Send is already done */
  626 
  627         ib_mark_mad_done(mad_send_wr);
  628         spin_unlock_irqrestore(&agent->lock, flags);
  629 
  630         wc.status = IB_WC_REM_ABORT_ERR;
  631         wc.vendor_err = rmpp_status;
  632         wc.send_buf = &mad_send_wr->send_buf;
  633         ib_mad_complete_send_wr(mad_send_wr, &wc);
  634         return;
  635 out:
  636         spin_unlock_irqrestore(&agent->lock, flags);
  637 }
  638 
  639 static inline void adjust_last_ack(struct ib_mad_send_wr_private *wr,
  640                                    int seg_num)
  641 {
  642         struct list_head *list;
  643 
  644         wr->last_ack = seg_num;
  645         list = &wr->last_ack_seg->list;
  646         list_for_each_entry(wr->last_ack_seg, list, list)
  647                 if (wr->last_ack_seg->num == seg_num)
  648                         break;
  649 }
  650 
  651 static void process_ds_ack(struct ib_mad_agent_private *agent,
  652                            struct ib_mad_recv_wc *mad_recv_wc, int newwin)
  653 {
  654         struct mad_rmpp_recv *rmpp_recv;
  655 
  656         rmpp_recv = find_rmpp_recv(agent, mad_recv_wc);
  657         if (rmpp_recv && rmpp_recv->state == RMPP_STATE_COMPLETE)
  658                 rmpp_recv->repwin = newwin;
  659 }
  660 
  661 static void process_rmpp_ack(struct ib_mad_agent_private *agent,
  662                              struct ib_mad_recv_wc *mad_recv_wc)
  663 {
  664         struct ib_mad_send_wr_private *mad_send_wr;
  665         struct ib_rmpp_mad *rmpp_mad;
  666         unsigned long flags;
  667         int seg_num, newwin, ret;
  668 
  669         rmpp_mad = (struct ib_rmpp_mad *)mad_recv_wc->recv_buf.mad;
  670         if (rmpp_mad->rmpp_hdr.rmpp_status) {
  671                 abort_send(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_BAD_STATUS);
  672                 nack_recv(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_BAD_STATUS);
  673                 return;
  674         }
  675 
  676         seg_num = be32_to_cpu(rmpp_mad->rmpp_hdr.seg_num);
  677         newwin = be32_to_cpu(rmpp_mad->rmpp_hdr.paylen_newwin);
  678         if (newwin < seg_num) {
  679                 abort_send(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_W2S);
  680                 nack_recv(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_W2S);
  681                 return;
  682         }
  683 
  684         spin_lock_irqsave(&agent->lock, flags);
  685         mad_send_wr = ib_find_send_mad(agent, mad_recv_wc);
  686         if (!mad_send_wr) {
  687                 if (!seg_num)
  688                         process_ds_ack(agent, mad_recv_wc, newwin);
  689                 goto out;       /* Unmatched or DS RMPP ACK */
  690         }
  691 
  692         if ((mad_send_wr->last_ack == mad_send_wr->send_buf.seg_count) &&
  693             (mad_send_wr->timeout)) {
  694                 spin_unlock_irqrestore(&agent->lock, flags);
  695                 ack_ds_ack(agent, mad_recv_wc);
  696                 return;         /* Repeated ACK for DS RMPP transaction */
  697         }
  698 
  699         if ((mad_send_wr->last_ack == mad_send_wr->send_buf.seg_count) ||
  700             (!mad_send_wr->timeout) || (mad_send_wr->status != IB_WC_SUCCESS))
  701                 goto out;       /* Send is already done */
  702 
  703         if (seg_num > mad_send_wr->send_buf.seg_count ||
  704             seg_num > mad_send_wr->newwin) {
  705                 spin_unlock_irqrestore(&agent->lock, flags);
  706                 abort_send(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_S2B);
  707                 nack_recv(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_S2B);
  708                 return;
  709         }
  710 
  711         if (newwin < mad_send_wr->newwin || seg_num < mad_send_wr->last_ack)
  712                 goto out;       /* Old ACK */
  713 
  714         if (seg_num > mad_send_wr->last_ack) {
  715                 adjust_last_ack(mad_send_wr, seg_num);
  716                 mad_send_wr->retries_left = mad_send_wr->max_retries;
  717         }
  718         mad_send_wr->newwin = newwin;
  719         if (mad_send_wr->last_ack == mad_send_wr->send_buf.seg_count) {
  720                 /* If no response is expected, the ACK completes the send */
  721                 if (!mad_send_wr->send_buf.timeout_ms) {
  722                         struct ib_mad_send_wc wc;
  723 
  724                         ib_mark_mad_done(mad_send_wr);
  725                         spin_unlock_irqrestore(&agent->lock, flags);
  726 
  727                         wc.status = IB_WC_SUCCESS;
  728                         wc.vendor_err = 0;
  729                         wc.send_buf = &mad_send_wr->send_buf;
  730                         ib_mad_complete_send_wr(mad_send_wr, &wc);
  731                         return;
  732                 }
  733                 if (mad_send_wr->refcount == 1)
  734                         ib_reset_mad_timeout(mad_send_wr,
  735                                              mad_send_wr->send_buf.timeout_ms);
  736                 spin_unlock_irqrestore(&agent->lock, flags);
  737                 ack_ds_ack(agent, mad_recv_wc);
  738                 return;
  739         } else if (mad_send_wr->refcount == 1 &&
  740                    mad_send_wr->seg_num < mad_send_wr->newwin &&
  741                    mad_send_wr->seg_num < mad_send_wr->send_buf.seg_count) {
  742                 /* Send failure will just result in a timeout/retry */
  743                 ret = send_next_seg(mad_send_wr);
  744                 if (ret)
  745                         goto out;
  746 
  747                 mad_send_wr->refcount++;
  748                 list_move_tail(&mad_send_wr->agent_list,
  749                               &mad_send_wr->mad_agent_priv->send_list);
  750         }
  751 out:
  752         spin_unlock_irqrestore(&agent->lock, flags);
  753 }
  754 
  755 static struct ib_mad_recv_wc *
  756 process_rmpp_data(struct ib_mad_agent_private *agent,
  757                   struct ib_mad_recv_wc *mad_recv_wc)
  758 {
  759         struct ib_rmpp_hdr *rmpp_hdr;
  760         u8 rmpp_status;
  761 
  762         rmpp_hdr = &((struct ib_rmpp_mad *)mad_recv_wc->recv_buf.mad)->rmpp_hdr;
  763 
  764         if (rmpp_hdr->rmpp_status) {
  765                 rmpp_status = IB_MGMT_RMPP_STATUS_BAD_STATUS;
  766                 goto bad;
  767         }
  768 
  769         if (rmpp_hdr->seg_num == cpu_to_be32(1)) {
  770                 if (!(ib_get_rmpp_flags(rmpp_hdr) & IB_MGMT_RMPP_FLAG_FIRST)) {
  771                         rmpp_status = IB_MGMT_RMPP_STATUS_BAD_SEG;
  772                         goto bad;
  773                 }
  774                 return start_rmpp(agent, mad_recv_wc);
  775         } else {
  776                 if (ib_get_rmpp_flags(rmpp_hdr) & IB_MGMT_RMPP_FLAG_FIRST) {
  777                         rmpp_status = IB_MGMT_RMPP_STATUS_BAD_SEG;
  778                         goto bad;
  779                 }
  780                 return continue_rmpp(agent, mad_recv_wc);
  781         }
  782 bad:
  783         nack_recv(agent, mad_recv_wc, rmpp_status);
  784         ib_free_recv_mad(mad_recv_wc);
  785         return NULL;
  786 }
  787 
  788 static void process_rmpp_stop(struct ib_mad_agent_private *agent,
  789                               struct ib_mad_recv_wc *mad_recv_wc)
  790 {
  791         struct ib_rmpp_mad *rmpp_mad;
  792 
  793         rmpp_mad = (struct ib_rmpp_mad *)mad_recv_wc->recv_buf.mad;
  794 
  795         if (rmpp_mad->rmpp_hdr.rmpp_status != IB_MGMT_RMPP_STATUS_RESX) {
  796                 abort_send(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_BAD_STATUS);
  797                 nack_recv(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_BAD_STATUS);
  798         } else
  799                 abort_send(agent, mad_recv_wc, rmpp_mad->rmpp_hdr.rmpp_status);
  800 }
  801 
  802 static void process_rmpp_abort(struct ib_mad_agent_private *agent,
  803                                struct ib_mad_recv_wc *mad_recv_wc)
  804 {
  805         struct ib_rmpp_mad *rmpp_mad;
  806 
  807         rmpp_mad = (struct ib_rmpp_mad *)mad_recv_wc->recv_buf.mad;
  808 
  809         if (rmpp_mad->rmpp_hdr.rmpp_status < IB_MGMT_RMPP_STATUS_ABORT_MIN ||
  810             rmpp_mad->rmpp_hdr.rmpp_status > IB_MGMT_RMPP_STATUS_ABORT_MAX) {
  811                 abort_send(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_BAD_STATUS);
  812                 nack_recv(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_BAD_STATUS);
  813         } else
  814                 abort_send(agent, mad_recv_wc, rmpp_mad->rmpp_hdr.rmpp_status);
  815 }
  816 
  817 struct ib_mad_recv_wc *
  818 ib_process_rmpp_recv_wc(struct ib_mad_agent_private *agent,
  819                         struct ib_mad_recv_wc *mad_recv_wc)
  820 {
  821         struct ib_rmpp_mad *rmpp_mad;
  822 
  823         rmpp_mad = (struct ib_rmpp_mad *)mad_recv_wc->recv_buf.mad;
  824         if (!(rmpp_mad->rmpp_hdr.rmpp_rtime_flags & IB_MGMT_RMPP_FLAG_ACTIVE))
  825                 return mad_recv_wc;
  826 
  827         if (rmpp_mad->rmpp_hdr.rmpp_version != IB_MGMT_RMPP_VERSION) {
  828                 abort_send(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_UNV);
  829                 nack_recv(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_UNV);
  830                 goto out;
  831         }
  832 
  833         switch (rmpp_mad->rmpp_hdr.rmpp_type) {
  834         case IB_MGMT_RMPP_TYPE_DATA:
  835                 return process_rmpp_data(agent, mad_recv_wc);
  836         case IB_MGMT_RMPP_TYPE_ACK:
  837                 process_rmpp_ack(agent, mad_recv_wc);
  838                 break;
  839         case IB_MGMT_RMPP_TYPE_STOP:
  840                 process_rmpp_stop(agent, mad_recv_wc);
  841                 break;
  842         case IB_MGMT_RMPP_TYPE_ABORT:
  843                 process_rmpp_abort(agent, mad_recv_wc);
  844                 break;
  845         default:
  846                 abort_send(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_BADT);
  847                 nack_recv(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_BADT);
  848                 break;
  849         }
  850 out:
  851         ib_free_recv_mad(mad_recv_wc);
  852         return NULL;
  853 }
  854 
  855 static int init_newwin(struct ib_mad_send_wr_private *mad_send_wr)
  856 {
  857         struct ib_mad_agent_private *agent = mad_send_wr->mad_agent_priv;
  858         struct ib_mad_hdr *mad_hdr = mad_send_wr->send_buf.mad;
  859         struct mad_rmpp_recv *rmpp_recv;
  860         struct ib_ah_attr ah_attr;
  861         unsigned long flags;
  862         int newwin = 1;
  863 
  864         if (!(mad_hdr->method & IB_MGMT_METHOD_RESP))
  865                 goto out;
  866 
  867         spin_lock_irqsave(&agent->lock, flags);
  868         list_for_each_entry(rmpp_recv, &agent->rmpp_list, list) {
  869                 if (rmpp_recv->tid != mad_hdr->tid ||
  870                     rmpp_recv->mgmt_class != mad_hdr->mgmt_class ||
  871                     rmpp_recv->class_version != mad_hdr->class_version ||
  872                     (rmpp_recv->method & IB_MGMT_METHOD_RESP))
  873                         continue;
  874 
  875                 if (ib_query_ah(mad_send_wr->send_buf.ah, &ah_attr))
  876                         continue;
  877 
  878                 if (rmpp_recv->slid == ah_attr.dlid) {
  879                         newwin = rmpp_recv->repwin;
  880                         break;
  881                 }
  882         }
  883         spin_unlock_irqrestore(&agent->lock, flags);
  884 out:
  885         return newwin;
  886 }
  887 
  888 int ib_send_rmpp_mad(struct ib_mad_send_wr_private *mad_send_wr)
  889 {
  890         struct ib_rmpp_mad *rmpp_mad;
  891         int ret;
  892 
  893         rmpp_mad = mad_send_wr->send_buf.mad;
  894         if (!(ib_get_rmpp_flags(&rmpp_mad->rmpp_hdr) &
  895               IB_MGMT_RMPP_FLAG_ACTIVE))
  896                 return IB_RMPP_RESULT_UNHANDLED;
  897 
  898         if (rmpp_mad->rmpp_hdr.rmpp_type != IB_MGMT_RMPP_TYPE_DATA) {
  899                 mad_send_wr->seg_num = 1;
  900                 return IB_RMPP_RESULT_INTERNAL;
  901         }
  902 
  903         mad_send_wr->newwin = init_newwin(mad_send_wr);
  904 
  905         /* We need to wait for the final ACK even if there isn't a response */
  906         mad_send_wr->refcount += (mad_send_wr->timeout == 0);
  907         ret = send_next_seg(mad_send_wr);
  908         if (!ret)
  909                 return IB_RMPP_RESULT_CONSUMED;
  910         return ret;
  911 }
  912 
  913 int ib_process_rmpp_send_wc(struct ib_mad_send_wr_private *mad_send_wr,
  914                             struct ib_mad_send_wc *mad_send_wc)
  915 {
  916         struct ib_rmpp_mad *rmpp_mad;
  917         int ret;
  918 
  919         rmpp_mad = mad_send_wr->send_buf.mad;
  920         if (!(ib_get_rmpp_flags(&rmpp_mad->rmpp_hdr) &
  921               IB_MGMT_RMPP_FLAG_ACTIVE))
  922                 return IB_RMPP_RESULT_UNHANDLED; /* RMPP not active */
  923 
  924         if (rmpp_mad->rmpp_hdr.rmpp_type != IB_MGMT_RMPP_TYPE_DATA)
  925                 return IB_RMPP_RESULT_INTERNAL;  /* ACK, STOP, or ABORT */
  926 
  927         if (mad_send_wc->status != IB_WC_SUCCESS ||
  928             mad_send_wr->status != IB_WC_SUCCESS)
  929                 return IB_RMPP_RESULT_PROCESSED; /* Canceled or send error */
  930 
  931         if (!mad_send_wr->timeout)
  932                 return IB_RMPP_RESULT_PROCESSED; /* Response received */
  933 
  934         if (mad_send_wr->last_ack == mad_send_wr->send_buf.seg_count) {
  935                 mad_send_wr->timeout =
  936                         msecs_to_jiffies(mad_send_wr->send_buf.timeout_ms);
  937                 return IB_RMPP_RESULT_PROCESSED; /* Send done */
  938         }
  939 
  940         if (mad_send_wr->seg_num == mad_send_wr->newwin ||
  941             mad_send_wr->seg_num == mad_send_wr->send_buf.seg_count)
  942                 return IB_RMPP_RESULT_PROCESSED; /* Wait for ACK */
  943 
  944         ret = send_next_seg(mad_send_wr);
  945         if (ret) {
  946                 mad_send_wc->status = IB_WC_GENERAL_ERR;
  947                 return IB_RMPP_RESULT_PROCESSED;
  948         }
  949         return IB_RMPP_RESULT_CONSUMED;
  950 }
  951 
  952 int ib_retry_rmpp(struct ib_mad_send_wr_private *mad_send_wr)
  953 {
  954         struct ib_rmpp_mad *rmpp_mad;
  955         int ret;
  956 
  957         rmpp_mad = mad_send_wr->send_buf.mad;
  958         if (!(ib_get_rmpp_flags(&rmpp_mad->rmpp_hdr) &
  959               IB_MGMT_RMPP_FLAG_ACTIVE))
  960                 return IB_RMPP_RESULT_UNHANDLED; /* RMPP not active */
  961 
  962         if (mad_send_wr->last_ack == mad_send_wr->send_buf.seg_count)
  963                 return IB_RMPP_RESULT_PROCESSED;
  964 
  965         mad_send_wr->seg_num = mad_send_wr->last_ack;
  966         mad_send_wr->cur_seg = mad_send_wr->last_ack_seg;
  967 
  968         ret = send_next_seg(mad_send_wr);
  969         if (ret)
  970                 return IB_RMPP_RESULT_PROCESSED;
  971 
  972         return IB_RMPP_RESULT_CONSUMED;
  973 }

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