lustre/ptlrpc/niobuf.c

   1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2  * vim:expandtab:shiftwidth=8:tabstop=8:
   3  *
   4  *  Copyright (c) 2002, 2003 Cluster File Systems, Inc.
   5  *
   6  *   This file is part of Lustre, http://www.lustre.org.
   7  *
   8  *   Lustre is free software; you can redistribute it and/or
   9  *   modify it under the terms of version 2 of the GNU General Public
  10  *   License as published by the Free Software Foundation.
  11  *
  12  *   Lustre is distributed in the hope that it will be useful,
  13  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *   GNU General Public License for more details.
  16  *
  17  *   You should have received a copy of the GNU General Public License
  18  *   along with Lustre; if not, write to the Free Software
  19  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20  *
  21  */
  22
  23 #define DEBUG_SUBSYSTEM S_RPC
  24 #ifndef __KERNEL__
  25 #include <liblustre.h>
  26 #include <portals/lib-types.h>
  27 #endif
  28 #include <linux/obd_support.h>
  29 #include <linux/lustre_net.h>
  30 #include <linux/lustre_lib.h>
  31 #include <linux/obd.h>
  32 #include "ptlrpc_internal.h"
  33
  34 static int ptl_send_buf (ptl_handle_md_t *mdh, void *base, int len,
  35                          ptl_ack_req_t ack, struct ptlrpc_cb_id *cbid,
  36                          struct ptlrpc_connection *conn, int portal, __u64 xid)
  37 {
  38         ptl_process_id_t remote_id;
  39         int              rc;
  40         int              rc2;
  41         ptl_md_t         md;
  42         char str[PTL_NALFMT_SIZE];
  43         ENTRY;
  44
  45         LASSERT (portal != 0);
  46         LASSERT (conn != NULL);
  47         CDEBUG (D_INFO, "conn=%p ni %s nid "LPX64" (%s) on %s\n",
  48                 conn, conn->c_peer.peer_ni->pni_name,
  49                 conn->c_peer.peer_nid,
  50                 portals_nid2str(conn->c_peer.peer_ni->pni_number,
  51                                 conn->c_peer.peer_nid, str),
  52                 conn->c_peer.peer_ni->pni_name);
  53
  54         remote_id.nid = conn->c_peer.peer_nid,
  55         remote_id.pid = 0;
  56
  57         md.start     = base;
  58         md.length    = len;
  59         md.threshold = (ack == PTL_ACK_REQ) ? 2 : 1;
  60         md.options   = PTLRPC_MD_OPTIONS;
  61         md.user_ptr  = cbid;
  62         md.eventq    = conn->c_peer.peer_ni->pni_eq_h;
  63
  64         if (ack == PTL_ACK_REQ &&
  65             OBD_FAIL_CHECK(OBD_FAIL_PTLRPC_ACK | OBD_FAIL_ONCE)) {
  66                 /* don't ask for the ack to simulate failing client */
  67                 ack = PTL_NOACK_REQ;
  68                 obd_fail_loc |= OBD_FAIL_ONCE | OBD_FAILED;
  69         }
  70
  71         rc = PtlMDBind (conn->c_peer.peer_ni->pni_ni_h, md,
  72                         PTL_UNLINK, mdh);
  73         if (rc != PTL_OK) {
  74                 CERROR ("PtlMDBind failed: %d\n", rc);
  75                 LASSERT (rc == PTL_NO_SPACE);
  76                 RETURN (-ENOMEM);
  77         }
  78
  79         CDEBUG(D_NET, "Sending %d bytes to portal %d, xid "LPD64"\n",
  80                len, portal, xid);
  81
  82         rc2 = PtlPut (*mdh, ack, remote_id, portal, 0, xid, 0, 0);
  83         if (rc != PTL_OK) {
  84                 /* We're going to get an UNLINK event when I unlink below,
  85                  * which will complete just like any other failed send, so
  86                  * I fall through and return success here! */
  87                 CERROR("PtlPut("LPU64", %d, "LPD64") failed: %d\n",
  88                        remote_id.nid, portal, xid, rc);
  89                 rc2 = PtlMDUnlink(*mdh);
  90                 LASSERT (rc2 == PTL_OK);
  91         }
  92
  93         RETURN (0);
  94 }
  95
  96 static void ptlrpc_fill_md(ptl_md_t *md, struct ptlrpc_bulk_desc *desc)
  97 {
  98         LASSERT(ptl_md_max_iovs() == 0  ||
  99                 (desc->bd_iov_count <= ptl_md_max_iovs()));
 100
 101         if (ptl_requires_iov() || desc->bd_iov_count > 0) {
 102                 md->options |= PTLRPC_PTL_MD_IOV;
 103                 md->start = &desc->bd_iov[0];
 104                 md->niov = desc->bd_iov_count;
 105         } else {
 106                 md->start = ptl_iov_base(&desc->bd_iov[0]);
 107         }
 108 }
 109
 110 int ptlrpc_start_bulk_transfer (struct ptlrpc_bulk_desc *desc)
 111 {
 112         int                 rc;
 113         int                 rc2;
 114         struct ptlrpc_peer *peer;
 115         ptl_process_id_t    remote_id;
 116         ptl_md_t            md;
 117         __u64               xid;
 118         ENTRY;
 119
 120         if (OBD_FAIL_CHECK_ONCE(OBD_FAIL_PTLRPC_BULK_PUT_NET))
 121                 RETURN(0);
 122
 123         /* NB no locking required until desc is on the network */
 124         LASSERT (!desc->bd_network_rw);
 125         LASSERT (desc->bd_type == BULK_PUT_SOURCE ||
 126                  desc->bd_type == BULK_GET_SINK);
 127         desc->bd_success = 0;
 128         peer = &desc->bd_export->exp_connection->c_peer;
 129
 130         md.length = desc->bd_nob;
 131         md.eventq = peer->peer_ni->pni_eq_h;
 132         md.threshold = 2; /* SENT and ACK/REPLY */
 133         md.options = PTLRPC_MD_OPTIONS;
 134
 135         ptlrpc_fill_md(&md, desc);
 136         md.user_ptr = &desc->bd_cbid;
 137         LASSERT (desc->bd_cbid.cbid_fn == server_bulk_callback);
 138         LASSERT (desc->bd_cbid.cbid_arg == desc);
 139
 140         /* NB total length may be 0 for a read past EOF, so we send a 0
 141          * length bulk, since the client expects a bulk event. */
 142
 143         rc = PtlMDBind(peer->peer_ni->pni_ni_h, md,
 144                        PTL_UNLINK, &desc->bd_md_h);
 145         if (rc != PTL_OK) {
 146                 CERROR("PtlMDBind failed: %d\n", rc);
 147                 LASSERT (rc == PTL_NO_SPACE);
 148                 RETURN(-ENOMEM);
 149         }
 150
 151         /* Client's bulk and reply matchbits are the same */
 152         xid = desc->bd_req->rq_xid;
 153         remote_id.nid = peer->peer_nid;
 154         remote_id.pid = 0;
 155
 156         CDEBUG(D_NET, "Transferring %u pages %u bytes via portal %d on %s "
 157                "nid "LPX64" pid %d xid "LPX64"\n",
 158                md.niov, md.length, desc->bd_portal, peer->peer_ni->pni_name,
 159                remote_id.nid, remote_id.pid, xid);
 160
 161         /* Network is about to get at the memory */
 162         desc->bd_network_rw = 1;
 163
 164         if (desc->bd_type == BULK_PUT_SOURCE)
 165                 rc = PtlPut (desc->bd_md_h, PTL_ACK_REQ, remote_id,
 166                              desc->bd_portal, 0, xid, 0, 0);
 167         else
 168                 rc = PtlGet (desc->bd_md_h, remote_id,
 169                              desc->bd_portal, 0, xid, 0);
 170
 171         if (rc != PTL_OK) {
 172                 /* Can't send, so we unlink the MD bound above.  The UNLINK
 173                  * event this creates will signal completion with failure,
 174                  * so we return SUCCESS here! */
 175                 CERROR("Transfer("LPU64", %d, "LPX64") failed: %d\n",
 176                        remote_id.nid, desc->bd_portal, xid, rc);
 177                 rc2 = PtlMDUnlink(desc->bd_md_h);
 178                 LASSERT (rc2 == PTL_OK);
 179         }
 180
 181         RETURN(0);
 182 }
 183
 184 void ptlrpc_abort_bulk (struct ptlrpc_bulk_desc *desc)
 185 {
 186         /* Server side bulk abort. Idempotent. Not thread-safe (i.e. only
 187          * serialises with completion callback) */
 188         struct l_wait_info lwi;
 189         int                rc;
 190
 191         LASSERT (!in_interrupt ());             /* might sleep */
 192
 193         if (!ptlrpc_bulk_active(desc))          /* completed or */
 194                 return;                         /* never started */
 195
 196         /* The unlink ensures the callback happens ASAP and is the last
 197          * one.  If it fails, it must be because completion just
 198          * happened. */
 199
 200         rc = PtlMDUnlink (desc->bd_md_h);
 201         if (rc == PTL_MD_INVALID) {
 202                 LASSERT(!ptlrpc_bulk_active(desc));
 203                 return;
 204         }
 205
 206         LASSERT (rc == PTL_OK);
 207
 208         for (;;) {
 209                 /* Network access will complete in finite time but the HUGE
 210                  * timeout lets us CWARN for visibility of sluggish NALs */
 211                 lwi = LWI_TIMEOUT (300 * HZ, NULL, NULL);
 212                 rc = l_wait_event(desc->bd_waitq,
 213                                   !ptlrpc_bulk_active(desc), &lwi);
 214                 if (rc == 0)
 215                         return;
 216
 217                 LASSERT(rc == -ETIMEDOUT);
 218                 CWARN("Unexpectedly long timeout: desc %p\n", desc);
 219         }
 220 }
 221
 222 int ptlrpc_register_bulk (struct ptlrpc_request *req)
 223 {
 224         struct ptlrpc_bulk_desc *desc = req->rq_bulk;
 225         struct ptlrpc_peer *peer;
 226         int rc;
 227         int rc2;
 228         ptl_process_id_t source_id;
 229         ptl_handle_me_t  me_h;
 230         ptl_md_t         md;
 231         ENTRY;
 232
 233         if (OBD_FAIL_CHECK_ONCE(OBD_FAIL_PTLRPC_BULK_GET_NET))
 234                 RETURN(0);
 235
 236         /* NB no locking required until desc is on the network */
 237         LASSERT (desc->bd_nob > 0);
 238         LASSERT (!desc->bd_network_rw);
 239         LASSERT (desc->bd_iov_count <= PTLRPC_MAX_BRW_PAGES);
 240         LASSERT (desc->bd_req != NULL);
 241         LASSERT (desc->bd_type == BULK_PUT_SINK ||
 242                  desc->bd_type == BULK_GET_SOURCE);
 243
 244         desc->bd_success = 0;
 245
 246         peer = &desc->bd_import->imp_connection->c_peer;
 247
 248         md.length = desc->bd_nob;
 249         md.eventq = peer->peer_ni->pni_eq_h;
 250         md.threshold = 1;                       /* PUT or GET */
 251         md.options = PTLRPC_MD_OPTIONS |
 252                      ((desc->bd_type == BULK_GET_SOURCE) ?
 253                       PTL_MD_OP_GET : PTL_MD_OP_PUT);
 254         ptlrpc_fill_md(&md, desc);
 255         md.user_ptr = &desc->bd_cbid;
 256         LASSERT (desc->bd_cbid.cbid_fn == client_bulk_callback);
 257         LASSERT (desc->bd_cbid.cbid_arg == desc);
 258
 259         /* XXX Registering the same xid on retried bulk makes my head
 260          * explode trying to understand how the original request's bulk
 261          * might interfere with the retried request -eeb */
 262         LASSERT (!desc->bd_registered || req->rq_xid != desc->bd_last_xid);
 263         desc->bd_registered = 1;
 264         desc->bd_last_xid = req->rq_xid;
 265
 266         source_id.nid = desc->bd_import->imp_connection->c_peer.peer_nid;
 267         source_id.pid = PTL_PID_ANY;
 268
 269         rc = PtlMEAttach(peer->peer_ni->pni_ni_h,
 270                          desc->bd_portal, source_id, req->rq_xid, 0,
 271                          PTL_UNLINK, PTL_INS_AFTER, &me_h);
 272         if (rc != PTL_OK) {
 273                 CERROR("PtlMEAttach failed: %d\n", rc);
 274                 LASSERT (rc == PTL_NO_SPACE);
 275                 RETURN (-ENOMEM);
 276         }
 277
 278         /* About to let the network at it... */
 279         desc->bd_network_rw = 1;
 280         rc = PtlMDAttach(me_h, md, PTL_UNLINK, &desc->bd_md_h);
 281         if (rc != PTL_OK) {
 282                 CERROR("PtlMDAttach failed: %d\n", rc);
 283                 LASSERT (rc == PTL_NO_SPACE);
 284                 desc->bd_network_rw = 0;
 285                 rc2 = PtlMEUnlink (me_h);
 286                 LASSERT (rc2 == PTL_OK);
 287                 RETURN (-ENOMEM);
 288         }
 289
 290         CDEBUG(D_NET, "Setup bulk %s buffers: %u pages %u bytes, xid "LPX64", "
 291                "portal %u on %s\n",
 292                desc->bd_type == BULK_GET_SOURCE ? "get-source" : "put-sink",
 293                md.niov, md.length,
 294                req->rq_xid, desc->bd_portal, peer->peer_ni->pni_name);
 295         RETURN(0);
 296 }
 297
 298 void ptlrpc_unregister_bulk (struct ptlrpc_request *req)
 299 {
 300         /* Disconnect a bulk desc from the network. Idempotent. Not
 301          * thread-safe (i.e. only interlocks with completion callback). */
 302         struct ptlrpc_bulk_desc *desc = req->rq_bulk;
 303         wait_queue_head_t       *wq;
 304         struct l_wait_info       lwi;
 305         int                      rc;
 306
 307         LASSERT (!in_interrupt ());             /* might sleep */
 308
 309         if (!ptlrpc_bulk_active(desc))          /* completed or */
 310                 return;                         /* never registered */
 311
 312         LASSERT (desc->bd_req == req);          /* bd_req NULL until registered */
 313
 314         /* the unlink ensures the callback happens ASAP and is the last
 315          * one.  If it fails, it must be because completion just
 316          * happened. */
 317
 318         rc = PtlMDUnlink (desc->bd_md_h);
 319         if (rc == PTL_MD_INVALID) {
 320                 LASSERT(!ptlrpc_bulk_active(desc));
 321                 return;
 322         }
 323
 324         LASSERT (rc == PTL_OK);
 325
 326         if (desc->bd_req->rq_set != NULL)
 327                 wq = &req->rq_set->set_waitq;
 328         else
 329                 wq = &req->rq_reply_waitq;
 330
 331         for (;;) {
 332                 /* Network access will complete in finite time but the HUGE
 333                  * timeout lets us CWARN for visibility of sluggish NALs */
 334                 lwi = LWI_TIMEOUT (300 * HZ, NULL, NULL);
 335                 rc = l_wait_event(*wq, !ptlrpc_bulk_active(desc), &lwi);
 336                 if (rc == 0)
 337                         return;
 338
 339                 LASSERT (rc == -ETIMEDOUT);
 340                 CWARN("Unexpectedly long timeout: desc %p\n", desc);
 341         }
 342 }
 343
 344 int ptlrpc_send_reply (struct ptlrpc_request *req, int may_be_difficult)
 345 {
 346         struct ptlrpc_service     *svc = req->rq_rqbd->rqbd_srv_ni->sni_service;
 347         struct ptlrpc_reply_state *rs = req->rq_reply_state;
 348         struct ptlrpc_connection  *conn;
 349         int                        rc;
 350
 351         /* We must already have a reply buffer (only ptlrpc_error() may be
 352          * called without one).  We must also have a request buffer which
 353          * is either the actual (swabbed) incoming request, or a saved copy
 354          * if this is a req saved in target_queue_final_reply(). */
 355         LASSERT (req->rq_reqmsg != NULL);
 356         LASSERT (rs != NULL);
 357         LASSERT (req->rq_repmsg != NULL);
 358         LASSERT (may_be_difficult || !rs->rs_difficult);
 359         LASSERT (req->rq_repmsg == &rs->rs_msg);
 360         LASSERT (rs->rs_cb_id.cbid_fn == reply_out_callback);
 361         LASSERT (rs->rs_cb_id.cbid_arg == rs);
 362
 363         LASSERT (req->rq_repmsg != NULL);
 364         if (req->rq_type != PTL_RPC_MSG_ERR)
 365                 req->rq_type = PTL_RPC_MSG_REPLY;
 366
 367         req->rq_repmsg->type   = req->rq_type;
 368         req->rq_repmsg->status = req->rq_status;
 369         req->rq_repmsg->opc    = req->rq_reqmsg->opc;
 370
 371         if (req->rq_export == NULL)
 372                 conn = ptlrpc_get_connection(&req->rq_peer, NULL);
 373         else
 374                 conn = ptlrpc_connection_addref(req->rq_export->exp_connection);
 375
 376         atomic_inc (&svc->srv_outstanding_replies);
 377
 378         rc = ptl_send_buf (&rs->rs_md_h, req->rq_repmsg, req->rq_replen,
 379                            rs->rs_difficult ? PTL_ACK_REQ : PTL_NOACK_REQ,
 380                            &rs->rs_cb_id, conn,
 381                            svc->srv_rep_portal, req->rq_xid);
 382         if (rc != 0) {
 383                 atomic_dec (&svc->srv_outstanding_replies);
 384
 385                 if (!rs->rs_difficult) {
 386                         /* Callers other than target_send_reply() expect me
 387                          * to clean up on a comms error */
 388                         lustre_free_reply_state (rs);
 389                         req->rq_reply_state = NULL;
 390                         req->rq_repmsg = NULL;
 391                 }
 392         }
 393         ptlrpc_put_connection(conn);
 394         return rc;
 395 }
 396
 397 int ptlrpc_reply (struct ptlrpc_request *req)
 398 {
 399         return (ptlrpc_send_reply (req, 0));
 400 }
 401
 402 int ptlrpc_error(struct ptlrpc_request *req)
 403 {
 404         int rc;
 405         ENTRY;
 406
 407         if (!req->rq_repmsg) {
 408                 rc = lustre_pack_reply(req, 0, NULL, NULL);
 409                 if (rc)
 410                         RETURN(rc);
 411         }
 412
 413         req->rq_type = PTL_RPC_MSG_ERR;
 414
 415         rc = ptlrpc_send_reply (req, 0);
 416         RETURN(rc);
 417 }
 418
 419 int ptl_send_rpc(struct ptlrpc_request *request)
 420 {
 421         int rc;
 422         int rc2;
 423         struct ptlrpc_connection *connection;
 424         unsigned long flags;
 425         ptl_process_id_t source_id;
 426         ptl_handle_me_t  reply_me_h;
 427         ptl_md_t         reply_md;
 428         ENTRY;
 429
 430         LASSERT (request->rq_type == PTL_RPC_MSG_REQUEST);
 431
 432         /* If this is a re-transmit, we're required to have disengaged
 433          * cleanly from the previous attempt */
 434         LASSERT (!request->rq_receiving_reply);
 435
 436         connection = request->rq_import->imp_connection;
 437
 438         if (request->rq_bulk != NULL) {
 439                 rc = ptlrpc_register_bulk (request);
 440                 if (rc != 0)
 441                         RETURN(rc);
 442         }
 443
 444         request->rq_reqmsg->handle = request->rq_import->imp_remote_handle;
 445         request->rq_reqmsg->type = PTL_RPC_MSG_REQUEST;
 446         request->rq_reqmsg->conn_cnt = request->rq_import->imp_conn_cnt;
 447
 448         source_id.nid = connection->c_peer.peer_nid;
 449         source_id.pid = PTL_PID_ANY;
 450
 451         LASSERT (request->rq_replen != 0);
 452         if (request->rq_repmsg == NULL)
 453                 OBD_ALLOC(request->rq_repmsg, request->rq_replen);
 454         if (request->rq_repmsg == NULL)
 455                 GOTO(cleanup_bulk, rc = -ENOMEM);
 456
 457         rc = PtlMEAttach(connection->c_peer.peer_ni->pni_ni_h,
 458                          request->rq_reply_portal, /* XXX FIXME bug 249 */
 459                          source_id, request->rq_xid, 0, PTL_UNLINK,
 460                          PTL_INS_AFTER, &reply_me_h);
 461         if (rc != PTL_OK) {
 462                 CERROR("PtlMEAttach failed: %d\n", rc);
 463                 LASSERT (rc == PTL_NO_SPACE);
 464                 GOTO(cleanup_repmsg, rc = -ENOMEM);
 465         }
 466
 467         spin_lock_irqsave (&request->rq_lock, flags);
 468         /* If the MD attach succeeds, there _will_ be a reply_in callback */
 469         request->rq_receiving_reply = 1;
 470         /* Clear any flags that may be present from previous sends. */
 471         request->rq_replied = 0;
 472         request->rq_err = 0;
 473         request->rq_timedout = 0;
 474         request->rq_resend = 0;
 475         request->rq_restart = 0;
 476         spin_unlock_irqrestore (&request->rq_lock, flags);
 477
 478         reply_md.start     = request->rq_repmsg;
 479         reply_md.length    = request->rq_replen;
 480         reply_md.threshold = 1;
 481         reply_md.options   = PTLRPC_MD_OPTIONS | PTL_MD_OP_PUT;
 482         reply_md.user_ptr  = &request->rq_reply_cbid;
 483         reply_md.eventq    = connection->c_peer.peer_ni->pni_eq_h;
 484
 485         rc = PtlMDAttach(reply_me_h, reply_md, PTL_UNLINK,
 486                          &request->rq_reply_md_h);
 487         if (rc != PTL_OK) {
 488                 CERROR("PtlMDAttach failed: %d\n", rc);
 489                 LASSERT (rc == PTL_NO_SPACE);
 490                 GOTO(cleanup_me, rc -ENOMEM);
 491         }
 492
 493         CDEBUG(D_NET, "Setup reply buffer: %u bytes, xid "LPU64
 494                ", portal %u on %s\n",
 495                request->rq_replen, request->rq_xid,
 496                request->rq_reply_portal,
 497                connection->c_peer.peer_ni->pni_name);
 498
 499         ptlrpc_request_addref(request);        /* +1 ref for the SENT callback */
 500
 501         request->rq_sent = LTIME_S(CURRENT_TIME);
 502         ptlrpc_pinger_sending_on_import(request->rq_import);
 503         rc = ptl_send_buf(&request->rq_req_md_h,
 504                           request->rq_reqmsg, request->rq_reqlen,
 505                           PTL_NOACK_REQ, &request->rq_req_cbid,
 506                           connection,
 507                           request->rq_request_portal,
 508                           request->rq_xid);
 509         if (rc == 0) {
 510                 ptlrpc_lprocfs_rpc_sent(request);
 511                 RETURN(rc);
 512         }
 513
 514         ptlrpc_req_finished (request);          /* drop callback ref */
 515
 516  cleanup_me:
 517         /* MEUnlink is safe; the PUT didn't even get off the ground, and
 518          * nobody apart from the PUT's target has the right nid+XID to
 519          * access the reply buffer. */
 520         rc2 = PtlMEUnlink(reply_me_h);
 521         LASSERT (rc2 == PTL_OK);
 522         /* UNLINKED callback called synchronously */
 523         LASSERT (!request->rq_receiving_reply);
 524
 525  cleanup_repmsg:
 526         OBD_FREE(request->rq_repmsg, request->rq_replen);
 527         request->rq_repmsg = NULL;
 528
 529  cleanup_bulk:
 530         if (request->rq_bulk != NULL)
 531                 ptlrpc_unregister_bulk(request);
 532
 533         return rc;
 534 }
 535
 536 int ptlrpc_register_rqbd (struct ptlrpc_request_buffer_desc *rqbd)
 537 {
 538         struct ptlrpc_srv_ni    *srv_ni = rqbd->rqbd_srv_ni;
 539         struct ptlrpc_service   *service = srv_ni->sni_service;
 540         static ptl_process_id_t  match_id = {PTL_NID_ANY, PTL_PID_ANY};
 541         int                      rc;
 542         ptl_md_t                 md;
 543         ptl_handle_me_t          me_h;
 544
 545         CDEBUG(D_NET, "PtlMEAttach: portal %d on %s\n",
 546                service->srv_req_portal, srv_ni->sni_ni->pni_name);
 547
 548         if (OBD_FAIL_CHECK_ONCE(OBD_FAIL_PTLRPC_RQBD))
 549                 return (-ENOMEM);
 550
 551         rc = PtlMEAttach(srv_ni->sni_ni->pni_ni_h, service->srv_req_portal,
 552                          match_id, 0, ~0, PTL_UNLINK, PTL_INS_AFTER, &me_h);
 553         if (rc != PTL_OK) {
 554                 CERROR("PtlMEAttach failed: %d\n", rc);
 555                 return (-ENOMEM);
 556         }
 557
 558         LASSERT(rqbd->rqbd_refcount == 0);
 559         rqbd->rqbd_refcount = 1;
 560
 561         md.start     = rqbd->rqbd_buffer;
 562         md.length    = service->srv_buf_size;
 563         md.max_size  = service->srv_max_req_size;
 564         md.threshold = PTL_MD_THRESH_INF;
 565         md.options   = PTLRPC_MD_OPTIONS | PTL_MD_OP_PUT | PTL_MD_MAX_SIZE;
 566         md.user_ptr  = &rqbd->rqbd_cbid;
 567         md.eventq    = srv_ni->sni_ni->pni_eq_h;
 568
 569         rc = PtlMDAttach(me_h, md, PTL_UNLINK, &rqbd->rqbd_md_h);
 570         if (rc == PTL_OK)
 571                 return (0);
 572
 573         CERROR("PtlMDAttach failed: %d; \n", rc);
 574         LASSERT (rc == PTL_NO_SPACE);
 575         rc = PtlMEUnlink (me_h);
 576         LASSERT (rc == PTL_OK);
 577         rqbd->rqbd_refcount = 0;
 578
 579         return (-ENOMEM);
 580 }