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   1 /*
   2  * Copyright (c) 2005-2007 Network Appliance, Inc. All rights reserved.
   3  *
   4  * This software is available to you under a choice of one of two
   5  * licenses.  You may choose to be licensed under the terms of the GNU
   6  * General Public License (GPL) Version 2, available from the file
   7  * COPYING in the main directory of this source tree, or the BSD-type
   8  * license below:
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  *
  14  *      Redistributions of source code must retain the above copyright
  15  *      notice, this list of conditions and the following disclaimer.
  16  *
  17  *      Redistributions in binary form must reproduce the above
  18  *      copyright notice, this list of conditions and the following
  19  *      disclaimer in the documentation and/or other materials provided
  20  *      with the distribution.
  21  *
  22  *      Neither the name of the Network Appliance, Inc. nor the names of
  23  *      its contributors may be used to endorse or promote products
  24  *      derived from this software without specific prior written
  25  *      permission.
  26  *
  27  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  28  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  29  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  30  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  31  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  32  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  33  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  34  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  35  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  36  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  37  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  38  *
  39  * Author: Tom Tucker <tom@opengridcomputing.com>
  40  */
  41
  42 #include <linux/sunrpc/svc_xprt.h>
  43 #include <linux/sunrpc/debug.h>
  44 #include <linux/sunrpc/rpc_rdma.h>
  45 #include <linux/spinlock.h>
  46 #include <rdma/ib_verbs.h>
  47 #include <rdma/rdma_cm.h>
  48 #include <linux/sunrpc/svc_rdma.h>
  49
  50 #define RPCDBG_FACILITY RPCDBG_SVCXPRT
  51
  52 static struct svc_xprt *svc_rdma_create(struct svc_serv *serv,
  53                                         struct sockaddr *sa, int salen,
  54                                         int flags);
  55 static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt);
  56 static void svc_rdma_release_rqst(struct svc_rqst *);
  57 static void dto_tasklet_func(unsigned long data);
  58 static void svc_rdma_detach(struct svc_xprt *xprt);
  59 static void svc_rdma_free(struct svc_xprt *xprt);
  60 static int svc_rdma_has_wspace(struct svc_xprt *xprt);
  61 static void rq_cq_reap(struct svcxprt_rdma *xprt);
  62 static void sq_cq_reap(struct svcxprt_rdma *xprt);
  63
  64 DECLARE_TASKLET(dto_tasklet, dto_tasklet_func, 0UL);
  65 static DEFINE_SPINLOCK(dto_lock);
  66 static LIST_HEAD(dto_xprt_q);
  67
  68 static struct svc_xprt_ops svc_rdma_ops = {
  69         .xpo_create = svc_rdma_create,
  70         .xpo_recvfrom = svc_rdma_recvfrom,
  71         .xpo_sendto = svc_rdma_sendto,
  72         .xpo_release_rqst = svc_rdma_release_rqst,
  73         .xpo_detach = svc_rdma_detach,
  74         .xpo_free = svc_rdma_free,
  75         .xpo_prep_reply_hdr = svc_rdma_prep_reply_hdr,
  76         .xpo_has_wspace = svc_rdma_has_wspace,
  77         .xpo_accept = svc_rdma_accept,
  78 };
  79
  80 struct svc_xprt_class svc_rdma_class = {
  81         .xcl_name = "rdma",
  82         .xcl_owner = THIS_MODULE,
  83         .xcl_ops = &svc_rdma_ops,
  84         .xcl_max_payload = RPCSVC_MAXPAYLOAD_TCP,
  85 };
  86
  87 static int rdma_bump_context_cache(struct svcxprt_rdma *xprt)
  88 {
  89         int target;
  90         int at_least_one = 0;
  91         struct svc_rdma_op_ctxt *ctxt;
  92
  93         target = min(xprt->sc_ctxt_cnt + xprt->sc_ctxt_bump,
  94                      xprt->sc_ctxt_max);
  95
  96         spin_lock_bh(&xprt->sc_ctxt_lock);
  97         while (xprt->sc_ctxt_cnt < target) {
  98                 xprt->sc_ctxt_cnt++;
  99                 spin_unlock_bh(&xprt->sc_ctxt_lock);
 100
 101                 ctxt = kmalloc(sizeof(*ctxt), GFP_KERNEL);
 102
 103                 spin_lock_bh(&xprt->sc_ctxt_lock);
 104                 if (ctxt) {
 105                         at_least_one = 1;
 106                         ctxt->next = xprt->sc_ctxt_head;
 107                         xprt->sc_ctxt_head = ctxt;
 108                 } else {
 109                         /* kmalloc failed...give up for now */
 110                         xprt->sc_ctxt_cnt--;
 111                         break;
 112                 }
 113         }
 114         spin_unlock_bh(&xprt->sc_ctxt_lock);
 115         dprintk("svcrdma: sc_ctxt_max=%d, sc_ctxt_cnt=%d\n",
 116                 xprt->sc_ctxt_max, xprt->sc_ctxt_cnt);
 117         return at_least_one;
 118 }
 119
 120 struct svc_rdma_op_ctxt *svc_rdma_get_context(struct svcxprt_rdma *xprt)
 121 {
 122         struct svc_rdma_op_ctxt *ctxt;
 123
 124         while (1) {
 125                 spin_lock_bh(&xprt->sc_ctxt_lock);
 126                 if (unlikely(xprt->sc_ctxt_head == NULL)) {
 127                         /* Try to bump my cache. */
 128                         spin_unlock_bh(&xprt->sc_ctxt_lock);
 129
 130                         if (rdma_bump_context_cache(xprt))
 131                                 continue;
 132
 133                         printk(KERN_INFO "svcrdma: sleeping waiting for "
 134                                "context memory on xprt=%p\n",
 135                                xprt);
 136                         schedule_timeout_uninterruptible(msecs_to_jiffies(500));
 137                         continue;
 138                 }
 139                 ctxt = xprt->sc_ctxt_head;
 140                 xprt->sc_ctxt_head = ctxt->next;
 141                 spin_unlock_bh(&xprt->sc_ctxt_lock);
 142                 ctxt->xprt = xprt;
 143                 INIT_LIST_HEAD(&ctxt->dto_q);
 144                 ctxt->count = 0;
 145                 break;
 146         }
 147         return ctxt;
 148 }
 149
 150 void svc_rdma_put_context(struct svc_rdma_op_ctxt *ctxt, int free_pages)
 151 {
 152         struct svcxprt_rdma *xprt;
 153         int i;
 154
 155         BUG_ON(!ctxt);
 156         xprt = ctxt->xprt;
 157         if (free_pages)
 158                 for (i = 0; i < ctxt->count; i++)
 159                         put_page(ctxt->pages[i]);
 160
 161         for (i = 0; i < ctxt->count; i++)
 162                 dma_unmap_single(xprt->sc_cm_id->device->dma_device,
 163                                  ctxt->sge[i].addr,
 164                                  ctxt->sge[i].length,
 165                                  ctxt->direction);
 166         spin_lock_bh(&xprt->sc_ctxt_lock);
 167         ctxt->next = xprt->sc_ctxt_head;
 168         xprt->sc_ctxt_head = ctxt;
 169         spin_unlock_bh(&xprt->sc_ctxt_lock);
 170 }
 171
 172 /* ib_cq event handler */
 173 static void cq_event_handler(struct ib_event *event, void *context)
 174 {
 175         struct svc_xprt *xprt = context;
 176         dprintk("svcrdma: received CQ event id=%d, context=%p\n",
 177                 event->event, context);
 178         set_bit(XPT_CLOSE, &xprt->xpt_flags);
 179 }
 180
 181 /* QP event handler */
 182 static void qp_event_handler(struct ib_event *event, void *context)
 183 {
 184         struct svc_xprt *xprt = context;
 185
 186         switch (event->event) {
 187         /* These are considered benign events */
 188         case IB_EVENT_PATH_MIG:
 189         case IB_EVENT_COMM_EST:
 190         case IB_EVENT_SQ_DRAINED:
 191         case IB_EVENT_QP_LAST_WQE_REACHED:
 192                 dprintk("svcrdma: QP event %d received for QP=%p\n",
 193                         event->event, event->element.qp);
 194                 break;
 195         /* These are considered fatal events */
 196         case IB_EVENT_PATH_MIG_ERR:
 197         case IB_EVENT_QP_FATAL:
 198         case IB_EVENT_QP_REQ_ERR:
 199         case IB_EVENT_QP_ACCESS_ERR:
 200         case IB_EVENT_DEVICE_FATAL:
 201         default:
 202                 dprintk("svcrdma: QP ERROR event %d received for QP=%p, "
 203                         "closing transport\n",
 204                         event->event, event->element.qp);
 205                 set_bit(XPT_CLOSE, &xprt->xpt_flags);
 206                 break;
 207         }
 208 }
 209
 210 /*
 211  * Data Transfer Operation Tasklet
 212  *
 213  * Walks a list of transports with I/O pending, removing entries as
 214  * they are added to the server's I/O pending list. Two bits indicate
 215  * if SQ, RQ, or both have I/O pending. The dto_lock is an irqsave
 216  * spinlock that serializes access to the transport list with the RQ
 217  * and SQ interrupt handlers.
 218  */
 219 static void dto_tasklet_func(unsigned long data)
 220 {
 221         struct svcxprt_rdma *xprt;
 222         unsigned long flags;
 223
 224         spin_lock_irqsave(&dto_lock, flags);
 225         while (!list_empty(&dto_xprt_q)) {
 226                 xprt = list_entry(dto_xprt_q.next,
 227                                   struct svcxprt_rdma, sc_dto_q);
 228                 list_del_init(&xprt->sc_dto_q);
 229                 spin_unlock_irqrestore(&dto_lock, flags);
 230
 231                 rq_cq_reap(xprt);
 232                 sq_cq_reap(xprt);
 233
 234                 svc_xprt_put(&xprt->sc_xprt);
 235                 spin_lock_irqsave(&dto_lock, flags);
 236         }
 237         spin_unlock_irqrestore(&dto_lock, flags);
 238 }
 239
 240 /*
 241  * Receive Queue Completion Handler
 242  *
 243  * Since an RQ completion handler is called on interrupt context, we
 244  * need to defer the handling of the I/O to a tasklet
 245  */
 246 static void rq_comp_handler(struct ib_cq *cq, void *cq_context)
 247 {
 248         struct svcxprt_rdma *xprt = cq_context;
 249         unsigned long flags;
 250
 251         /*
 252          * Set the bit regardless of whether or not it's on the list
 253          * because it may be on the list already due to an SQ
 254          * completion.
 255         */
 256         set_bit(RDMAXPRT_RQ_PENDING, &xprt->sc_flags);
 257
 258         /*
 259          * If this transport is not already on the DTO transport queue,
 260          * add it
 261          */
 262         spin_lock_irqsave(&dto_lock, flags);
 263         if (list_empty(&xprt->sc_dto_q)) {
 264                 svc_xprt_get(&xprt->sc_xprt);
 265                 list_add_tail(&xprt->sc_dto_q, &dto_xprt_q);
 266         }
 267         spin_unlock_irqrestore(&dto_lock, flags);
 268
 269         /* Tasklet does all the work to avoid irqsave locks. */
 270         tasklet_schedule(&dto_tasklet);
 271 }
 272
 273 /*
 274  * rq_cq_reap - Process the RQ CQ.
 275  *
 276  * Take all completing WC off the CQE and enqueue the associated DTO
 277  * context on the dto_q for the transport.
 278  */
 279 static void rq_cq_reap(struct svcxprt_rdma *xprt)
 280 {
 281         int ret;
 282         struct ib_wc wc;
 283         struct svc_rdma_op_ctxt *ctxt = NULL;
 284
 285         if (!test_and_clear_bit(RDMAXPRT_RQ_PENDING, &xprt->sc_flags))
 286                 return;
 287
 288         ib_req_notify_cq(xprt->sc_rq_cq, IB_CQ_NEXT_COMP);
 289         atomic_inc(&rdma_stat_rq_poll);
 290
 291         spin_lock_bh(&xprt->sc_rq_dto_lock);
 292         while ((ret = ib_poll_cq(xprt->sc_rq_cq, 1, &wc)) > 0) {
 293                 ctxt = (struct svc_rdma_op_ctxt *)(unsigned long)wc.wr_id;
 294                 ctxt->wc_status = wc.status;
 295                 ctxt->byte_len = wc.byte_len;
 296                 if (wc.status != IB_WC_SUCCESS) {
 297                         /* Close the transport */
 298                         set_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags);
 299                         svc_rdma_put_context(ctxt, 1);
 300                         continue;
 301                 }
 302                 list_add_tail(&ctxt->dto_q, &xprt->sc_rq_dto_q);
 303         }
 304         spin_unlock_bh(&xprt->sc_rq_dto_lock);
 305
 306         if (ctxt)
 307                 atomic_inc(&rdma_stat_rq_prod);
 308
 309         set_bit(XPT_DATA, &xprt->sc_xprt.xpt_flags);
 310         /*
 311          * If data arrived before established event,
 312          * don't enqueue. This defers RPC I/O until the
 313          * RDMA connection is complete.
 314          */
 315         if (!test_bit(RDMAXPRT_CONN_PENDING, &xprt->sc_flags))
 316                 svc_xprt_enqueue(&xprt->sc_xprt);
 317 }
 318
 319 /*
 320  * Send Queue Completion Handler - potentially called on interrupt context.
 321  */
 322 static void sq_cq_reap(struct svcxprt_rdma *xprt)
 323 {
 324         struct svc_rdma_op_ctxt *ctxt = NULL;
 325         struct ib_wc wc;
 326         struct ib_cq *cq = xprt->sc_sq_cq;
 327         int ret;
 328
 329
 330         if (!test_and_clear_bit(RDMAXPRT_SQ_PENDING, &xprt->sc_flags))
 331                 return;
 332
 333         ib_req_notify_cq(xprt->sc_sq_cq, IB_CQ_NEXT_COMP);
 334         atomic_inc(&rdma_stat_sq_poll);
 335         while ((ret = ib_poll_cq(cq, 1, &wc)) > 0) {
 336                 ctxt = (struct svc_rdma_op_ctxt *)(unsigned long)wc.wr_id;
 337                 xprt = ctxt->xprt;
 338
 339                 if (wc.status != IB_WC_SUCCESS)
 340                         /* Close the transport */
 341                         set_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags);
 342
 343                 /* Decrement used SQ WR count */
 344                 atomic_dec(&xprt->sc_sq_count);
 345                 wake_up(&xprt->sc_send_wait);
 346
 347                 switch (ctxt->wr_op) {
 348                 case IB_WR_SEND:
 349                 case IB_WR_RDMA_WRITE:
 350                         svc_rdma_put_context(ctxt, 1);
 351                         break;
 352
 353                 case IB_WR_RDMA_READ:
 354                         if (test_bit(RDMACTXT_F_LAST_CTXT, &ctxt->flags)) {
 355                                 set_bit(XPT_DATA, &xprt->sc_xprt.xpt_flags);
 356                                 set_bit(RDMACTXT_F_READ_DONE, &ctxt->flags);
 357                                 spin_lock_bh(&xprt->sc_read_complete_lock);
 358                                 list_add_tail(&ctxt->dto_q,
 359                                               &xprt->sc_read_complete_q);
 360                                 spin_unlock_bh(&xprt->sc_read_complete_lock);
 361                                 svc_xprt_enqueue(&xprt->sc_xprt);
 362                         }
 363                         break;
 364
 365                 default:
 366                         printk(KERN_ERR "svcrdma: unexpected completion type, "
 367                                "opcode=%d, status=%d\n",
 368                                wc.opcode, wc.status);
 369                         break;
 370                 }
 371         }
 372
 373         if (ctxt)
 374                 atomic_inc(&rdma_stat_sq_prod);
 375 }
 376
 377 static void sq_comp_handler(struct ib_cq *cq, void *cq_context)
 378 {
 379         struct svcxprt_rdma *xprt = cq_context;
 380         unsigned long flags;
 381
 382         /*
 383          * Set the bit regardless of whether or not it's on the list
 384          * because it may be on the list already due to an RQ
 385          * completion.
 386         */
 387         set_bit(RDMAXPRT_SQ_PENDING, &xprt->sc_flags);
 388
 389         /*
 390          * If this transport is not already on the DTO transport queue,
 391          * add it
 392          */
 393         spin_lock_irqsave(&dto_lock, flags);
 394         if (list_empty(&xprt->sc_dto_q)) {
 395                 svc_xprt_get(&xprt->sc_xprt);
 396                 list_add_tail(&xprt->sc_dto_q, &dto_xprt_q);
 397         }
 398         spin_unlock_irqrestore(&dto_lock, flags);
 399
 400         /* Tasklet does all the work to avoid irqsave locks. */
 401         tasklet_schedule(&dto_tasklet);
 402 }
 403
 404 static void create_context_cache(struct svcxprt_rdma *xprt,
 405                                  int ctxt_count, int ctxt_bump, int ctxt_max)
 406 {
 407         struct svc_rdma_op_ctxt *ctxt;
 408         int i;
 409
 410         xprt->sc_ctxt_max = ctxt_max;
 411         xprt->sc_ctxt_bump = ctxt_bump;
 412         xprt->sc_ctxt_cnt = 0;
 413         xprt->sc_ctxt_head = NULL;
 414         for (i = 0; i < ctxt_count; i++) {
 415                 ctxt = kmalloc(sizeof(*ctxt), GFP_KERNEL);
 416                 if (ctxt) {
 417                         ctxt->next = xprt->sc_ctxt_head;
 418                         xprt->sc_ctxt_head = ctxt;
 419                         xprt->sc_ctxt_cnt++;
 420                 }
 421         }
 422 }
 423
 424 static void destroy_context_cache(struct svc_rdma_op_ctxt *ctxt)
 425 {
 426         struct svc_rdma_op_ctxt *next;
 427         if (!ctxt)
 428                 return;
 429
 430         do {
 431                 next = ctxt->next;
 432                 kfree(ctxt);
 433                 ctxt = next;
 434         } while (next);
 435 }
 436
 437 static struct svcxprt_rdma *rdma_create_xprt(struct svc_serv *serv,
 438                                              int listener)
 439 {
 440         struct svcxprt_rdma *cma_xprt = kzalloc(sizeof *cma_xprt, GFP_KERNEL);
 441
 442         if (!cma_xprt)
 443                 return NULL;
 444         svc_xprt_init(&svc_rdma_class, &cma_xprt->sc_xprt, serv);
 445         INIT_LIST_HEAD(&cma_xprt->sc_accept_q);
 446         INIT_LIST_HEAD(&cma_xprt->sc_dto_q);
 447         INIT_LIST_HEAD(&cma_xprt->sc_rq_dto_q);
 448         INIT_LIST_HEAD(&cma_xprt->sc_read_complete_q);
 449         init_waitqueue_head(&cma_xprt->sc_send_wait);
 450
 451         spin_lock_init(&cma_xprt->sc_lock);
 452         spin_lock_init(&cma_xprt->sc_read_complete_lock);
 453         spin_lock_init(&cma_xprt->sc_ctxt_lock);
 454         spin_lock_init(&cma_xprt->sc_rq_dto_lock);
 455
 456         cma_xprt->sc_ord = svcrdma_ord;
 457
 458         cma_xprt->sc_max_req_size = svcrdma_max_req_size;
 459         cma_xprt->sc_max_requests = svcrdma_max_requests;
 460         cma_xprt->sc_sq_depth = svcrdma_max_requests * RPCRDMA_SQ_DEPTH_MULT;
 461         atomic_set(&cma_xprt->sc_sq_count, 0);
 462
 463         if (!listener) {
 464                 int reqs = cma_xprt->sc_max_requests;
 465                 create_context_cache(cma_xprt,
 466                                      reqs << 1, /* starting size */
 467                                      reqs,      /* bump amount */
 468                                      reqs +
 469                                      cma_xprt->sc_sq_depth +
 470                                      RPCRDMA_MAX_THREADS + 1); /* max */
 471                 if (!cma_xprt->sc_ctxt_head) {
 472                         kfree(cma_xprt);
 473                         return NULL;
 474                 }
 475                 clear_bit(XPT_LISTENER, &cma_xprt->sc_xprt.xpt_flags);
 476         } else
 477                 set_bit(XPT_LISTENER, &cma_xprt->sc_xprt.xpt_flags);
 478
 479         return cma_xprt;
 480 }
 481
 482 struct page *svc_rdma_get_page(void)
 483 {
 484         struct page *page;
 485
 486         while ((page = alloc_page(GFP_KERNEL)) == NULL) {
 487                 /* If we can't get memory, wait a bit and try again */
 488                 printk(KERN_INFO "svcrdma: out of memory...retrying in 1000 "
 489                        "jiffies.\n");
 490                 schedule_timeout_uninterruptible(msecs_to_jiffies(1000));
 491         }
 492         return page;
 493 }
 494
 495 int svc_rdma_post_recv(struct svcxprt_rdma *xprt)
 496 {
 497         struct ib_recv_wr recv_wr, *bad_recv_wr;
 498         struct svc_rdma_op_ctxt *ctxt;
 499         struct page *page;
 500         unsigned long pa;
 501         int sge_no;
 502         int buflen;
 503         int ret;
 504
 505         ctxt = svc_rdma_get_context(xprt);
 506         buflen = 0;
 507         ctxt->direction = DMA_FROM_DEVICE;
 508         for (sge_no = 0; buflen < xprt->sc_max_req_size; sge_no++) {
 509                 BUG_ON(sge_no >= xprt->sc_max_sge);
 510                 page = svc_rdma_get_page();
 511                 ctxt->pages[sge_no] = page;
 512                 pa = ib_dma_map_page(xprt->sc_cm_id->device,
 513                                      page, 0, PAGE_SIZE,
 514                                      DMA_FROM_DEVICE);
 515                 ctxt->sge[sge_no].addr = pa;
 516                 ctxt->sge[sge_no].length = PAGE_SIZE;
 517                 ctxt->sge[sge_no].lkey = xprt->sc_phys_mr->lkey;
 518                 buflen += PAGE_SIZE;
 519         }
 520         ctxt->count = sge_no;
 521         recv_wr.next = NULL;
 522         recv_wr.sg_list = &ctxt->sge[0];
 523         recv_wr.num_sge = ctxt->count;
 524         recv_wr.wr_id = (u64)(unsigned long)ctxt;
 525
 526         ret = ib_post_recv(xprt->sc_qp, &recv_wr, &bad_recv_wr);
 527         return ret;
 528 }
 529
 530 /*
 531  * This function handles the CONNECT_REQUEST event on a listening
 532  * endpoint. It is passed the cma_id for the _new_ connection. The context in
 533  * this cma_id is inherited from the listening cma_id and is the svc_xprt
 534  * structure for the listening endpoint.
 535  *
 536  * This function creates a new xprt for the new connection and enqueues it on
 537  * the accept queue for the listent xprt. When the listen thread is kicked, it
 538  * will call the recvfrom method on the listen xprt which will accept the new
 539  * connection.
 540  */
 541 static void handle_connect_req(struct rdma_cm_id *new_cma_id)
 542 {
 543         struct svcxprt_rdma *listen_xprt = new_cma_id->context;
 544         struct svcxprt_rdma *newxprt;
 545
 546         /* Create a new transport */
 547         newxprt = rdma_create_xprt(listen_xprt->sc_xprt.xpt_server, 0);
 548         if (!newxprt) {
 549                 dprintk("svcrdma: failed to create new transport\n");
 550                 return;
 551         }
 552         newxprt->sc_cm_id = new_cma_id;
 553         new_cma_id->context = newxprt;
 554         dprintk("svcrdma: Creating newxprt=%p, cm_id=%p, listenxprt=%p\n",
 555                 newxprt, newxprt->sc_cm_id, listen_xprt);
 556
 557         /*
 558          * Enqueue the new transport on the accept queue of the listening
 559          * transport
 560          */
 561         spin_lock_bh(&listen_xprt->sc_lock);
 562         list_add_tail(&newxprt->sc_accept_q, &listen_xprt->sc_accept_q);
 563         spin_unlock_bh(&listen_xprt->sc_lock);
 564
 565         /*
 566          * Can't use svc_xprt_received here because we are not on a
 567          * rqstp thread
 568         */
 569         set_bit(XPT_CONN, &listen_xprt->sc_xprt.xpt_flags);
 570         svc_xprt_enqueue(&listen_xprt->sc_xprt);
 571 }
 572
 573 /*
 574  * Handles events generated on the listening endpoint. These events will be
 575  * either be incoming connect requests or adapter removal  events.
 576  */
 577 static int rdma_listen_handler(struct rdma_cm_id *cma_id,
 578                                struct rdma_cm_event *event)
 579 {
 580         struct svcxprt_rdma *xprt = cma_id->context;
 581         int ret = 0;
 582
 583         switch (event->event) {
 584         case RDMA_CM_EVENT_CONNECT_REQUEST:
 585                 dprintk("svcrdma: Connect request on cma_id=%p, xprt = %p, "
 586                         "event=%d\n", cma_id, cma_id->context, event->event);
 587                 handle_connect_req(cma_id);
 588                 break;
 589
 590         case RDMA_CM_EVENT_ESTABLISHED:
 591                 /* Accept complete */
 592                 dprintk("svcrdma: Connection completed on LISTEN xprt=%p, "
 593                         "cm_id=%p\n", xprt, cma_id);
 594                 break;
 595
 596         case RDMA_CM_EVENT_DEVICE_REMOVAL:
 597                 dprintk("svcrdma: Device removal xprt=%p, cm_id=%p\n",
 598                         xprt, cma_id);
 599                 if (xprt)
 600                         set_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags);
 601                 break;
 602
 603         default:
 604                 dprintk("svcrdma: Unexpected event on listening endpoint %p, "
 605                         "event=%d\n", cma_id, event->event);
 606                 break;
 607         }
 608
 609         return ret;
 610 }
 611
 612 static int rdma_cma_handler(struct rdma_cm_id *cma_id,
 613                             struct rdma_cm_event *event)
 614 {
 615         struct svc_xprt *xprt = cma_id->context;
 616         struct svcxprt_rdma *rdma =
 617                 container_of(xprt, struct svcxprt_rdma, sc_xprt);
 618         switch (event->event) {
 619         case RDMA_CM_EVENT_ESTABLISHED:
 620                 /* Accept complete */
 621                 svc_xprt_get(xprt);
 622                 dprintk("svcrdma: Connection completed on DTO xprt=%p, "
 623                         "cm_id=%p\n", xprt, cma_id);
 624                 clear_bit(RDMAXPRT_CONN_PENDING, &rdma->sc_flags);
 625                 svc_xprt_enqueue(xprt);
 626                 break;
 627         case RDMA_CM_EVENT_DISCONNECTED:
 628                 dprintk("svcrdma: Disconnect on DTO xprt=%p, cm_id=%p\n",
 629                         xprt, cma_id);
 630                 if (xprt) {
 631                         set_bit(XPT_CLOSE, &xprt->xpt_flags);
 632                         svc_xprt_enqueue(xprt);
 633                 }
 634                 break;
 635         case RDMA_CM_EVENT_DEVICE_REMOVAL:
 636                 dprintk("svcrdma: Device removal cma_id=%p, xprt = %p, "
 637                         "event=%d\n", cma_id, xprt, event->event);
 638                 if (xprt) {
 639                         set_bit(XPT_CLOSE, &xprt->xpt_flags);
 640                         svc_xprt_enqueue(xprt);
 641                 }
 642                 break;
 643         default:
 644                 dprintk("svcrdma: Unexpected event on DTO endpoint %p, "
 645                         "event=%d\n", cma_id, event->event);
 646                 break;
 647         }
 648         return 0;
 649 }
 650
 651 /*
 652  * Create a listening RDMA service endpoint.
 653  */
 654 static struct svc_xprt *svc_rdma_create(struct svc_serv *serv,
 655                                         struct sockaddr *sa, int salen,
 656                                         int flags)
 657 {
 658         struct rdma_cm_id *listen_id;
 659         struct svcxprt_rdma *cma_xprt;
 660         struct svc_xprt *xprt;
 661         int ret;
 662
 663         dprintk("svcrdma: Creating RDMA socket\n");
 664
 665         cma_xprt = rdma_create_xprt(serv, 1);
 666         if (!cma_xprt)
 667                 return ERR_PTR(ENOMEM);
 668         xprt = &cma_xprt->sc_xprt;
 669
 670         listen_id = rdma_create_id(rdma_listen_handler, cma_xprt, RDMA_PS_TCP);
 671         if (IS_ERR(listen_id)) {
 672                 svc_xprt_put(&cma_xprt->sc_xprt);
 673                 dprintk("svcrdma: rdma_create_id failed = %ld\n",
 674                         PTR_ERR(listen_id));
 675                 return (void *)listen_id;
 676         }
 677         ret = rdma_bind_addr(listen_id, sa);
 678         if (ret) {
 679                 rdma_destroy_id(listen_id);
 680                 svc_xprt_put(&cma_xprt->sc_xprt);
 681                 dprintk("svcrdma: rdma_bind_addr failed = %d\n", ret);
 682                 return ERR_PTR(ret);
 683         }
 684         cma_xprt->sc_cm_id = listen_id;
 685
 686         ret = rdma_listen(listen_id, RPCRDMA_LISTEN_BACKLOG);
 687         if (ret) {
 688                 rdma_destroy_id(listen_id);
 689                 svc_xprt_put(&cma_xprt->sc_xprt);
 690                 dprintk("svcrdma: rdma_listen failed = %d\n", ret);
 691                 return ERR_PTR(ret);
 692         }
 693
 694         /*
 695          * We need to use the address from the cm_id in case the
 696          * caller specified 0 for the port number.
 697          */
 698         sa = (struct sockaddr *)&cma_xprt->sc_cm_id->route.addr.src_addr;
 699         svc_xprt_set_local(&cma_xprt->sc_xprt, sa, salen);
 700
 701         return &cma_xprt->sc_xprt;
 702 }
 703
 704 /*
 705  * This is the xpo_recvfrom function for listening endpoints. Its
 706  * purpose is to accept incoming connections. The CMA callback handler
 707  * has already created a new transport and attached it to the new CMA
 708  * ID.
 709  *
 710  * There is a queue of pending connections hung on the listening
 711  * transport. This queue contains the new svc_xprt structure. This
 712  * function takes svc_xprt structures off the accept_q and completes
 713  * the connection.
 714  */
 715 static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt)
 716 {
 717         struct svcxprt_rdma *listen_rdma;
 718         struct svcxprt_rdma *newxprt = NULL;
 719         struct rdma_conn_param conn_param;
 720         struct ib_qp_init_attr qp_attr;
 721         struct ib_device_attr devattr;
 722         struct sockaddr *sa;
 723         int ret;
 724         int i;
 725
 726         listen_rdma = container_of(xprt, struct svcxprt_rdma, sc_xprt);
 727         clear_bit(XPT_CONN, &xprt->xpt_flags);
 728         /* Get the next entry off the accept list */
 729         spin_lock_bh(&listen_rdma->sc_lock);
 730         if (!list_empty(&listen_rdma->sc_accept_q)) {
 731                 newxprt = list_entry(listen_rdma->sc_accept_q.next,
 732                                      struct svcxprt_rdma, sc_accept_q);
 733                 list_del_init(&newxprt->sc_accept_q);
 734         }
 735         if (!list_empty(&listen_rdma->sc_accept_q))
 736                 set_bit(XPT_CONN, &listen_rdma->sc_xprt.xpt_flags);
 737         spin_unlock_bh(&listen_rdma->sc_lock);
 738         if (!newxprt)
 739                 return NULL;
 740
 741         dprintk("svcrdma: newxprt from accept queue = %p, cm_id=%p\n",
 742                 newxprt, newxprt->sc_cm_id);
 743
 744         ret = ib_query_device(newxprt->sc_cm_id->device, &devattr);
 745         if (ret) {
 746                 dprintk("svcrdma: could not query device attributes on "
 747                         "device %p, rc=%d\n", newxprt->sc_cm_id->device, ret);
 748                 goto errout;
 749         }
 750
 751         /* Qualify the transport resource defaults with the
 752          * capabilities of this particular device */
 753         newxprt->sc_max_sge = min((size_t)devattr.max_sge,
 754                                   (size_t)RPCSVC_MAXPAGES);
 755         newxprt->sc_max_requests = min((size_t)devattr.max_qp_wr,
 756                                    (size_t)svcrdma_max_requests);
 757         newxprt->sc_sq_depth = RPCRDMA_SQ_DEPTH_MULT * newxprt->sc_max_requests;
 758
 759         newxprt->sc_ord =  min((size_t)devattr.max_qp_rd_atom,
 760                                (size_t)svcrdma_ord);
 761
 762         newxprt->sc_pd = ib_alloc_pd(newxprt->sc_cm_id->device);
 763         if (IS_ERR(newxprt->sc_pd)) {
 764                 dprintk("svcrdma: error creating PD for connect request\n");
 765                 goto errout;
 766         }
 767         newxprt->sc_sq_cq = ib_create_cq(newxprt->sc_cm_id->device,
 768                                          sq_comp_handler,
 769                                          cq_event_handler,
 770                                          newxprt,
 771                                          newxprt->sc_sq_depth,
 772                                          0);
 773         if (IS_ERR(newxprt->sc_sq_cq)) {
 774                 dprintk("svcrdma: error creating SQ CQ for connect request\n");
 775                 goto errout;
 776         }
 777         newxprt->sc_rq_cq = ib_create_cq(newxprt->sc_cm_id->device,
 778                                          rq_comp_handler,
 779                                          cq_event_handler,
 780                                          newxprt,
 781                                          newxprt->sc_max_requests,
 782                                          0);
 783         if (IS_ERR(newxprt->sc_rq_cq)) {
 784                 dprintk("svcrdma: error creating RQ CQ for connect request\n");
 785                 goto errout;
 786         }
 787
 788         memset(&qp_attr, 0, sizeof qp_attr);
 789         qp_attr.event_handler = qp_event_handler;
 790         qp_attr.qp_context = &newxprt->sc_xprt;
 791         qp_attr.cap.max_send_wr = newxprt->sc_sq_depth;
 792         qp_attr.cap.max_recv_wr = newxprt->sc_max_requests;
 793         qp_attr.cap.max_send_sge = newxprt->sc_max_sge;
 794         qp_attr.cap.max_recv_sge = newxprt->sc_max_sge;
 795         qp_attr.sq_sig_type = IB_SIGNAL_REQ_WR;
 796         qp_attr.qp_type = IB_QPT_RC;
 797         qp_attr.send_cq = newxprt->sc_sq_cq;
 798         qp_attr.recv_cq = newxprt->sc_rq_cq;
 799         dprintk("svcrdma: newxprt->sc_cm_id=%p, newxprt->sc_pd=%p\n"
 800                 "    cm_id->device=%p, sc_pd->device=%p\n"
 801                 "    cap.max_send_wr = %d\n"
 802                 "    cap.max_recv_wr = %d\n"
 803                 "    cap.max_send_sge = %d\n"
 804                 "    cap.max_recv_sge = %d\n",
 805                 newxprt->sc_cm_id, newxprt->sc_pd,
 806                 newxprt->sc_cm_id->device, newxprt->sc_pd->device,
 807                 qp_attr.cap.max_send_wr,
 808                 qp_attr.cap.max_recv_wr,
 809                 qp_attr.cap.max_send_sge,
 810                 qp_attr.cap.max_recv_sge);
 811
 812         ret = rdma_create_qp(newxprt->sc_cm_id, newxprt->sc_pd, &qp_attr);
 813         if (ret) {
 814                 /*
 815                  * XXX: This is a hack. We need a xx_request_qp interface
 816                  * that will adjust the qp_attr's with a best-effort
 817                  * number
 818                  */
 819                 qp_attr.cap.max_send_sge -= 2;
 820                 qp_attr.cap.max_recv_sge -= 2;
 821                 ret = rdma_create_qp(newxprt->sc_cm_id, newxprt->sc_pd,
 822                                      &qp_attr);
 823                 if (ret) {
 824                         dprintk("svcrdma: failed to create QP, ret=%d\n", ret);
 825                         goto errout;
 826                 }
 827                 newxprt->sc_max_sge = qp_attr.cap.max_send_sge;
 828                 newxprt->sc_max_sge = qp_attr.cap.max_recv_sge;
 829                 newxprt->sc_sq_depth = qp_attr.cap.max_send_wr;
 830                 newxprt->sc_max_requests = qp_attr.cap.max_recv_wr;
 831         }
 832         svc_xprt_get(&newxprt->sc_xprt);
 833         newxprt->sc_qp = newxprt->sc_cm_id->qp;
 834
 835         /* Register all of physical memory */
 836         newxprt->sc_phys_mr = ib_get_dma_mr(newxprt->sc_pd,
 837                                             IB_ACCESS_LOCAL_WRITE |
 838                                             IB_ACCESS_REMOTE_WRITE);
 839         if (IS_ERR(newxprt->sc_phys_mr)) {
 840                 dprintk("svcrdma: Failed to create DMA MR ret=%d\n", ret);
 841                 goto errout;
 842         }
 843
 844         /* Post receive buffers */
 845         for (i = 0; i < newxprt->sc_max_requests; i++) {
 846                 ret = svc_rdma_post_recv(newxprt);
 847                 if (ret) {
 848                         dprintk("svcrdma: failure posting receive buffers\n");
 849                         goto errout;
 850                 }
 851         }
 852
 853         /* Swap out the handler */
 854         newxprt->sc_cm_id->event_handler = rdma_cma_handler;
 855
 856         /* Accept Connection */
 857         set_bit(RDMAXPRT_CONN_PENDING, &newxprt->sc_flags);
 858         memset(&conn_param, 0, sizeof conn_param);
 859         conn_param.responder_resources = 0;
 860         conn_param.initiator_depth = newxprt->sc_ord;
 861         ret = rdma_accept(newxprt->sc_cm_id, &conn_param);
 862         if (ret) {
 863                 dprintk("svcrdma: failed to accept new connection, ret=%d\n",
 864                        ret);
 865                 goto errout;
 866         }
 867
 868         dprintk("svcrdma: new connection %p accepted with the following "
 869                 "attributes:\n"
 870                 "    local_ip        : %d.%d.%d.%d\n"
 871                 "    local_port      : %d\n"
 872                 "    remote_ip       : %d.%d.%d.%d\n"
 873                 "    remote_port     : %d\n"
 874                 "    max_sge         : %d\n"
 875                 "    sq_depth        : %d\n"
 876                 "    max_requests    : %d\n"
 877                 "    ord             : %d\n",
 878                 newxprt,
 879                 NIPQUAD(((struct sockaddr_in *)&newxprt->sc_cm_id->
 880                          route.addr.src_addr)->sin_addr.s_addr),
 881                 ntohs(((struct sockaddr_in *)&newxprt->sc_cm_id->
 882                        route.addr.src_addr)->sin_port),
 883                 NIPQUAD(((struct sockaddr_in *)&newxprt->sc_cm_id->
 884                          route.addr.dst_addr)->sin_addr.s_addr),
 885                 ntohs(((struct sockaddr_in *)&newxprt->sc_cm_id->
 886                        route.addr.dst_addr)->sin_port),
 887                 newxprt->sc_max_sge,
 888                 newxprt->sc_sq_depth,
 889                 newxprt->sc_max_requests,
 890                 newxprt->sc_ord);
 891
 892         /* Set the local and remote addresses in the transport */
 893         sa = (struct sockaddr *)&newxprt->sc_cm_id->route.addr.dst_addr;
 894         svc_xprt_set_remote(&newxprt->sc_xprt, sa, svc_addr_len(sa));
 895         sa = (struct sockaddr *)&newxprt->sc_cm_id->route.addr.src_addr;
 896         svc_xprt_set_local(&newxprt->sc_xprt, sa, svc_addr_len(sa));
 897
 898         ib_req_notify_cq(newxprt->sc_sq_cq, IB_CQ_NEXT_COMP);
 899         ib_req_notify_cq(newxprt->sc_rq_cq, IB_CQ_NEXT_COMP);
 900         return &newxprt->sc_xprt;
 901
 902  errout:
 903         dprintk("svcrdma: failure accepting new connection rc=%d.\n", ret);
 904         /* Take a reference in case the DTO handler runs */
 905         svc_xprt_get(&newxprt->sc_xprt);
 906         if (newxprt->sc_qp && !IS_ERR(newxprt->sc_qp)) {
 907                 ib_destroy_qp(newxprt->sc_qp);
 908                 svc_xprt_put(&newxprt->sc_xprt);
 909         }
 910         rdma_destroy_id(newxprt->sc_cm_id);
 911         /* This call to put will destroy the transport */
 912         svc_xprt_put(&newxprt->sc_xprt);
 913         return NULL;
 914 }
 915
 916 static void svc_rdma_release_rqst(struct svc_rqst *rqstp)
 917 {
 918 }
 919
 920 /*
 921  * When connected, an svc_xprt has at least three references:
 922  *
 923  * - A reference held by the QP. We still hold that here because this
 924  *   code deletes the QP and puts the reference.
 925  *
 926  * - A reference held by the cm_id between the ESTABLISHED and
 927  *   DISCONNECTED events. If the remote peer disconnected first, this
 928  *   reference could be gone.
 929  *
 930  * - A reference held by the svc_recv code that called this function
 931  *   as part of close processing.
 932  *
 933  * At a minimum two references should still be held.
 934  */
 935 static void svc_rdma_detach(struct svc_xprt *xprt)
 936 {
 937         struct svcxprt_rdma *rdma =
 938                 container_of(xprt, struct svcxprt_rdma, sc_xprt);
 939         dprintk("svc: svc_rdma_detach(%p)\n", xprt);
 940
 941         /* Disconnect and flush posted WQE */
 942         rdma_disconnect(rdma->sc_cm_id);
 943
 944         /* Destroy the QP if present (not a listener) */
 945         if (rdma->sc_qp && !IS_ERR(rdma->sc_qp)) {
 946                 ib_destroy_qp(rdma->sc_qp);
 947                 svc_xprt_put(xprt);
 948         }
 949
 950         /* Destroy the CM ID */
 951         rdma_destroy_id(rdma->sc_cm_id);
 952 }
 953
 954 static void svc_rdma_free(struct svc_xprt *xprt)
 955 {
 956         struct svcxprt_rdma *rdma = (struct svcxprt_rdma *)xprt;
 957         dprintk("svcrdma: svc_rdma_free(%p)\n", rdma);
 958         /* We should only be called from kref_put */
 959         BUG_ON(atomic_read(&xprt->xpt_ref.refcount) != 0);
 960         if (rdma->sc_sq_cq && !IS_ERR(rdma->sc_sq_cq))
 961                 ib_destroy_cq(rdma->sc_sq_cq);
 962
 963         if (rdma->sc_rq_cq && !IS_ERR(rdma->sc_rq_cq))
 964                 ib_destroy_cq(rdma->sc_rq_cq);
 965
 966         if (rdma->sc_phys_mr && !IS_ERR(rdma->sc_phys_mr))
 967                 ib_dereg_mr(rdma->sc_phys_mr);
 968
 969         if (rdma->sc_pd && !IS_ERR(rdma->sc_pd))
 970                 ib_dealloc_pd(rdma->sc_pd);
 971
 972         destroy_context_cache(rdma->sc_ctxt_head);
 973         kfree(rdma);
 974 }
 975
 976 static int svc_rdma_has_wspace(struct svc_xprt *xprt)
 977 {
 978         struct svcxprt_rdma *rdma =
 979                 container_of(xprt, struct svcxprt_rdma, sc_xprt);
 980
 981         /*
 982          * If there are fewer SQ WR available than required to send a
 983          * simple response, return false.
 984          */
 985         if ((rdma->sc_sq_depth - atomic_read(&rdma->sc_sq_count) < 3))
 986                 return 0;
 987
 988         /*
 989          * ...or there are already waiters on the SQ,
 990          * return false.
 991          */
 992         if (waitqueue_active(&rdma->sc_send_wait))
 993                 return 0;
 994
 995         /* Otherwise return true. */
 996         return 1;
 997 }
 998
 999 int svc_rdma_send(struct svcxprt_rdma *xprt, struct ib_send_wr *wr)
1000 {
1001         struct ib_send_wr *bad_wr;
1002         int ret;
1003
1004         if (test_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags))
1005                 return -ENOTCONN;
1006
1007         BUG_ON(wr->send_flags != IB_SEND_SIGNALED);
1008         BUG_ON(((struct svc_rdma_op_ctxt *)(unsigned long)wr->wr_id)->wr_op !=
1009                 wr->opcode);
1010         /* If the SQ is full, wait until an SQ entry is available */
1011         while (1) {
1012                 spin_lock_bh(&xprt->sc_lock);
1013                 if (xprt->sc_sq_depth == atomic_read(&xprt->sc_sq_count)) {
1014                         spin_unlock_bh(&xprt->sc_lock);
1015                         atomic_inc(&rdma_stat_sq_starve);
1016
1017                         /* See if we can opportunistically reap SQ WR to make room */
1018                         sq_cq_reap(xprt);
1019
1020                         /* Wait until SQ WR available if SQ still full */
1021                         wait_event(xprt->sc_send_wait,
1022                                    atomic_read(&xprt->sc_sq_count) <
1023                                    xprt->sc_sq_depth);
1024                         if (test_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags))
1025                                 return 0;
1026                         continue;
1027                 }
1028                 /* Bumped used SQ WR count and post */
1029                 ret = ib_post_send(xprt->sc_qp, wr, &bad_wr);
1030                 if (!ret)
1031                         atomic_inc(&xprt->sc_sq_count);
1032                 else
1033                         dprintk("svcrdma: failed to post SQ WR rc=%d, "
1034                                "sc_sq_count=%d, sc_sq_depth=%d\n",
1035                                ret, atomic_read(&xprt->sc_sq_count),
1036                                xprt->sc_sq_depth);
1037                 spin_unlock_bh(&xprt->sc_lock);
1038                 break;
1039         }
1040         return ret;
1041 }
1042
1043 int svc_rdma_send_error(struct svcxprt_rdma *xprt, struct rpcrdma_msg *rmsgp,
1044                         enum rpcrdma_errcode err)
1045 {
1046         struct ib_send_wr err_wr;
1047         struct ib_sge sge;
1048         struct page *p;
1049         struct svc_rdma_op_ctxt *ctxt;
1050         u32 *va;
1051         int length;
1052         int ret;
1053
1054         p = svc_rdma_get_page();
1055         va = page_address(p);
1056
1057         /* XDR encode error */
1058         length = svc_rdma_xdr_encode_error(xprt, rmsgp, err, va);
1059
1060         /* Prepare SGE for local address */
1061         sge.addr = ib_dma_map_page(xprt->sc_cm_id->device,
1062                                    p, 0, PAGE_SIZE, DMA_FROM_DEVICE);
1063         sge.lkey = xprt->sc_phys_mr->lkey;
1064         sge.length = length;
1065
1066         ctxt = svc_rdma_get_context(xprt);
1067         ctxt->count = 1;
1068         ctxt->pages[0] = p;
1069
1070         /* Prepare SEND WR */
1071         memset(&err_wr, 0, sizeof err_wr);
1072         ctxt->wr_op = IB_WR_SEND;
1073         err_wr.wr_id = (unsigned long)ctxt;
1074         err_wr.sg_list = &sge;
1075         err_wr.num_sge = 1;
1076         err_wr.opcode = IB_WR_SEND;
1077         err_wr.send_flags = IB_SEND_SIGNALED;
1078
1079         /* Post It */
1080         ret = svc_rdma_send(xprt, &err_wr);
1081         if (ret) {
1082                 dprintk("svcrdma: Error posting send = %d\n", ret);
1083                 svc_rdma_put_context(ctxt, 1);
1084         }
1085
1086         return ret;
1087 }