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