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         int              rc;
  38         int              rc2;
  39         ptl_md_t         md;
  40         char str[PTL_NALFMT_SIZE];
  41         ENTRY;
  42
  43         LASSERT (portal != 0);
  44         LASSERT (conn != NULL);
  45         CDEBUG (D_INFO, "conn=%p ni %s id %s on %s\n",
  46                 conn, conn->c_peer.peer_ni->pni_name,
  47                 ptlrpc_id2str(&conn->c_peer, str),
  48                 conn->c_peer.peer_ni->pni_name);
  49         md.start     = base;
  50         md.length    = len;
  51         md.threshold = (ack == PTL_ACK_REQ) ? 2 : 1;
  52         md.options   = PTLRPC_MD_OPTIONS;
  53         md.user_ptr  = cbid;
  54         md.eventq    = conn->c_peer.peer_ni->pni_eq_h;
  55
  56         if (ack == PTL_ACK_REQ &&
  57             OBD_FAIL_CHECK(OBD_FAIL_PTLRPC_ACK | OBD_FAIL_ONCE)) {
  58                 /* don't ask for the ack to simulate failing client */
  59                 ack = PTL_NOACK_REQ;
  60                 obd_fail_loc |= OBD_FAIL_ONCE | OBD_FAILED;
  61         }
  62
  63         rc = PtlMDBind (conn->c_peer.peer_ni->pni_ni_h, md,
  64                         PTL_UNLINK, mdh);
  65         if (rc != PTL_OK) {
  66                 CERROR ("PtlMDBind failed: %d\n", rc);
  67                 LASSERT (rc == PTL_NO_SPACE);
  68                 RETURN (-ENOMEM);
  69         }
  70
  71         CDEBUG(D_NET, "Sending %d bytes to portal %d, xid "LPD64"\n",
  72                len, portal, xid);
  73
  74         rc = PtlPut (*mdh, ack, conn->c_peer.peer_id, portal, 0, xid, 0, 0);
  75         if (rc != PTL_OK) {
  76                 /* We're going to get an UNLINK event when I unlink below,
  77                  * which will complete just like any other failed send, so
  78                  * I fall through and return success here! */
  79                 CERROR("PtlPut(%s, %d, "LPD64") failed: %d\n",
  80                        ptlrpc_id2str(&conn->c_peer, str),
  81                        portal, xid, rc);
  82                 rc2 = PtlMDUnlink(*mdh);
  83                 LASSERT (rc2 == PTL_OK);
  84         }
  85
  86         RETURN (0);
  87 }
  88
  89 int ptlrpc_start_bulk_transfer (struct ptlrpc_bulk_desc *desc)
  90 {
  91         int                 rc;
  92         int                 rc2;
  93         struct ptlrpc_peer *peer;
  94         ptl_md_t            md;
  95         __u64               xid;
  96         char                str[PTL_NALFMT_SIZE];
  97         ENTRY;
  98
  99         if (OBD_FAIL_CHECK_ONCE(OBD_FAIL_PTLRPC_BULK_PUT_NET))
 100                 RETURN(0);
 101
 102         /* NB no locking required until desc is on the network */
 103         LASSERT (!desc->bd_network_rw);
 104         LASSERT (desc->bd_type == BULK_PUT_SOURCE ||
 105                  desc->bd_type == BULK_GET_SINK);
 106         desc->bd_success = 0;
 107         peer = &desc->bd_export->exp_connection->c_peer;
 108
 109         md.user_ptr = &desc->bd_cbid;
 110         md.eventq = peer->peer_ni->pni_eq_h;
 111         md.threshold = 2; /* SENT and ACK/REPLY */
 112         md.options = PTLRPC_MD_OPTIONS;
 113         ptlrpc_fill_bulk_md(&md, desc);
 114
 115         LASSERT (desc->bd_cbid.cbid_fn == server_bulk_callback);
 116         LASSERT (desc->bd_cbid.cbid_arg == desc);
 117
 118         /* NB total length may be 0 for a read past EOF, so we send a 0
 119          * length bulk, since the client expects a bulk event. */
 120
 121         rc = PtlMDBind(peer->peer_ni->pni_ni_h, md,
 122                        PTL_UNLINK, &desc->bd_md_h);
 123         if (rc != PTL_OK) {
 124                 CERROR("PtlMDBind failed: %d\n", rc);
 125                 LASSERT (rc == PTL_NO_SPACE);
 126                 RETURN(-ENOMEM);
 127         }
 128
 129         /* Client's bulk and reply matchbits are the same */
 130         xid = desc->bd_req->rq_xid;
 131         CDEBUG(D_NET, "Transferring %u pages %u bytes via portal %d on %s "
 132                "nid %s pid %d xid "LPX64"\n", desc->bd_iov_count,
 133                desc->bd_nob, desc->bd_portal, peer->peer_ni->pni_name,
 134                ptlrpc_id2str(peer, str), peer->peer_id.pid, xid);
 135
 136         /* Network is about to get at the memory */
 137         desc->bd_network_rw = 1;
 138
 139         if (desc->bd_type == BULK_PUT_SOURCE)
 140                 rc = PtlPut (desc->bd_md_h, PTL_ACK_REQ, peer->peer_id,
 141                              desc->bd_portal, 0, xid, 0, 0);
 142         else
 143                 rc = PtlGet (desc->bd_md_h, peer->peer_id,
 144                              desc->bd_portal, 0, xid, 0);
 145
 146         if (rc != PTL_OK) {
 147                 /* Can't send, so we unlink the MD bound above.  The UNLINK
 148                  * event this creates will signal completion with failure,
 149                  * so we return SUCCESS here! */
 150                 CERROR("Transfer(%s, %d, "LPX64") failed: %d\n",
 151                        ptlrpc_id2str(peer, str),
 152                        desc->bd_portal, xid, rc);
 153                 rc2 = PtlMDUnlink(desc->bd_md_h);
 154                 LASSERT (rc2 == PTL_OK);
 155         }
 156
 157         RETURN(0);
 158 }
 159
 160 void ptlrpc_abort_bulk (struct ptlrpc_bulk_desc *desc)
 161 {
 162         /* Server side bulk abort. Idempotent. Not thread-safe (i.e. only
 163          * serialises with completion callback) */
 164         struct l_wait_info lwi;
 165         int                rc;
 166
 167         LASSERT (!in_interrupt ());             /* might sleep */
 168
 169         if (!ptlrpc_bulk_active(desc))          /* completed or */
 170                 return;                         /* never started */
 171
 172         /* The unlink ensures the callback happens ASAP and is the last
 173          * one.  If it fails, it must be because completion just happened,
 174          * but we must still l_wait_event() in this case, to give liblustre
 175          * a chance to run server_bulk_callback()*/
 176
 177         PtlMDUnlink (desc->bd_md_h);
 178
 179         for (;;) {
 180                 /* Network access will complete in finite time but the HUGE
 181                  * timeout lets us CWARN for visibility of sluggish NALs */
 182                 lwi = LWI_TIMEOUT (300 * HZ, NULL, NULL);
 183                 rc = l_wait_event(desc->bd_waitq,
 184                                   !ptlrpc_bulk_active(desc), &lwi);
 185                 if (rc == 0)
 186                         return;
 187
 188                 LASSERT(rc == -ETIMEDOUT);
 189                 CWARN("Unexpectedly long timeout: desc %p\n", desc);
 190         }
 191 }
 192
 193 int ptlrpc_register_bulk (struct ptlrpc_request *req)
 194 {
 195         struct ptlrpc_bulk_desc *desc = req->rq_bulk;
 196         struct ptlrpc_peer *peer;
 197         int rc;
 198         int rc2;
 199         ptl_handle_me_t  me_h;
 200         ptl_md_t         md;
 201         ENTRY;
 202
 203         if (OBD_FAIL_CHECK_ONCE(OBD_FAIL_PTLRPC_BULK_GET_NET))
 204                 RETURN(0);
 205
 206         /* NB no locking required until desc is on the network */
 207         LASSERT (desc->bd_nob > 0);
 208         LASSERT (!desc->bd_network_rw);
 209         LASSERT (desc->bd_iov_count <= PTLRPC_MAX_BRW_PAGES);
 210         LASSERT (desc->bd_req != NULL);
 211         LASSERT (desc->bd_type == BULK_PUT_SINK ||
 212                  desc->bd_type == BULK_GET_SOURCE);
 213
 214         desc->bd_success = 0;
 215
 216         peer = &desc->bd_import->imp_connection->c_peer;
 217
 218         md.user_ptr = &desc->bd_cbid;
 219         md.eventq = peer->peer_ni->pni_eq_h;
 220         md.threshold = 1;                       /* PUT or GET */
 221         md.options = PTLRPC_MD_OPTIONS |
 222                      ((desc->bd_type == BULK_GET_SOURCE) ?
 223                       PTL_MD_OP_GET : PTL_MD_OP_PUT);
 224         ptlrpc_fill_bulk_md(&md, desc);
 225
 226         LASSERT (desc->bd_cbid.cbid_fn == client_bulk_callback);
 227         LASSERT (desc->bd_cbid.cbid_arg == desc);
 228
 229         /* XXX Registering the same xid on retried bulk makes my head
 230          * explode trying to understand how the original request's bulk
 231          * might interfere with the retried request -eeb */
 232         LASSERT (!desc->bd_registered || req->rq_xid != desc->bd_last_xid);
 233         desc->bd_registered = 1;
 234         desc->bd_last_xid = req->rq_xid;
 235
 236         rc = PtlMEAttach(peer->peer_ni->pni_ni_h,
 237                          desc->bd_portal, desc->bd_import->imp_connection->c_peer.peer_id,
 238                          req->rq_xid, 0, PTL_UNLINK, PTL_INS_AFTER, &me_h);
 239         if (rc != PTL_OK) {
 240                 CERROR("PtlMEAttach failed: %d\n", rc);
 241                 LASSERT (rc == PTL_NO_SPACE);
 242                 RETURN (-ENOMEM);
 243         }
 244
 245         /* About to let the network at it... */
 246         desc->bd_network_rw = 1;
 247         rc = PtlMDAttach(me_h, md, PTL_UNLINK, &desc->bd_md_h);
 248         if (rc != PTL_OK) {
 249                 CERROR("PtlMDAttach failed: %d\n", rc);
 250                 LASSERT (rc == PTL_NO_SPACE);
 251                 desc->bd_network_rw = 0;
 252                 rc2 = PtlMEUnlink (me_h);
 253                 LASSERT (rc2 == PTL_OK);
 254                 RETURN (-ENOMEM);
 255         }
 256
 257         CDEBUG(D_NET, "Setup bulk %s buffers: %u pages %u bytes, xid "LPX64", "
 258                "portal %u on %s\n",
 259                desc->bd_type == BULK_GET_SOURCE ? "get-source" : "put-sink",
 260                desc->bd_iov_count, desc->bd_nob,
 261                req->rq_xid, desc->bd_portal, peer->peer_ni->pni_name);
 262         RETURN(0);
 263 }
 264
 265 void ptlrpc_unregister_bulk (struct ptlrpc_request *req)
 266 {
 267         /* Disconnect a bulk desc from the network. Idempotent. Not
 268          * thread-safe (i.e. only interlocks with completion callback). */
 269         struct ptlrpc_bulk_desc *desc = req->rq_bulk;
 270         wait_queue_head_t       *wq;
 271         struct l_wait_info       lwi;
 272         int                      rc;
 273
 274         LASSERT (!in_interrupt ());             /* might sleep */
 275
 276         if (!ptlrpc_bulk_active(desc))          /* completed or */
 277                 return;                         /* never registered */
 278
 279         LASSERT (desc->bd_req == req);          /* bd_req NULL until registered */
 280
 281         /* the unlink ensures the callback happens ASAP and is the last
 282          * one.  If it fails, it must be because completion just happened,
 283          * but we must still l_wait_event() in this case to give liblustre
 284          * a chance to run client_bulk_callback() */
 285
 286         PtlMDUnlink (desc->bd_md_h);
 287
 288         if (desc->bd_req->rq_set != NULL)
 289                 wq = &req->rq_set->set_waitq;
 290         else
 291                 wq = &req->rq_reply_waitq;
 292
 293         for (;;) {
 294                 /* Network access will complete in finite time but the HUGE
 295                  * timeout lets us CWARN for visibility of sluggish NALs */
 296                 lwi = LWI_TIMEOUT (300 * HZ, NULL, NULL);
 297                 rc = l_wait_event(*wq, !ptlrpc_bulk_active(desc), &lwi);
 298                 if (rc == 0)
 299                         return;
 300
 301                 LASSERT (rc == -ETIMEDOUT);
 302                 CWARN("Unexpectedly long timeout: desc %p\n", desc);
 303         }
 304 }
 305
 306 int ptlrpc_send_reply (struct ptlrpc_request *req, int may_be_difficult)
 307 {
 308         struct ptlrpc_service     *svc = req->rq_rqbd->rqbd_srv_ni->sni_service;
 309         struct ptlrpc_reply_state *rs = req->rq_reply_state;
 310         struct ptlrpc_connection  *conn;
 311         int                        rc;
 312
 313         /* We must already have a reply buffer (only ptlrpc_error() may be
 314          * called without one).  We must also have a request buffer which
 315          * is either the actual (swabbed) incoming request, or a saved copy
 316          * if this is a req saved in target_queue_final_reply(). */
 317         LASSERT (req->rq_reqmsg != NULL);
 318         LASSERT (rs != NULL);
 319         LASSERT (req->rq_repmsg != NULL);
 320         LASSERT (may_be_difficult || !rs->rs_difficult);
 321         LASSERT (req->rq_repmsg == &rs->rs_msg);
 322         LASSERT (rs->rs_cb_id.cbid_fn == reply_out_callback);
 323         LASSERT (rs->rs_cb_id.cbid_arg == rs);
 324
 325         LASSERT (req->rq_repmsg != NULL);
 326         if (req->rq_type != PTL_RPC_MSG_ERR)
 327                 req->rq_type = PTL_RPC_MSG_REPLY;
 328
 329         req->rq_repmsg->type   = req->rq_type;
 330         req->rq_repmsg->status = req->rq_status;
 331         req->rq_repmsg->opc    = req->rq_reqmsg->opc;
 332
 333         if (req->rq_export == NULL)
 334                 conn = ptlrpc_get_connection(&req->rq_peer, NULL);
 335         else
 336                 conn = ptlrpc_connection_addref(req->rq_export->exp_connection);
 337
 338         atomic_inc (&svc->srv_outstanding_replies);
 339
 340         rc = ptl_send_buf (&rs->rs_md_h, req->rq_repmsg, req->rq_replen,
 341                            rs->rs_difficult ? PTL_ACK_REQ : PTL_NOACK_REQ,
 342                            &rs->rs_cb_id, conn,
 343                            svc->srv_rep_portal, req->rq_xid);
 344         if (rc != 0) {
 345                 atomic_dec (&svc->srv_outstanding_replies);
 346
 347                 if (!rs->rs_difficult) {
 348                         /* Callers other than target_send_reply() expect me
 349                          * to clean up on a comms error */
 350                         lustre_free_reply_state (rs);
 351                         req->rq_reply_state = NULL;
 352                         req->rq_repmsg = NULL;
 353                 }
 354         }
 355         ptlrpc_put_connection(conn);
 356         return rc;
 357 }
 358
 359 int ptlrpc_reply (struct ptlrpc_request *req)
 360 {
 361         return (ptlrpc_send_reply (req, 0));
 362 }
 363
 364 int ptlrpc_error(struct ptlrpc_request *req)
 365 {
 366         int rc;
 367         ENTRY;
 368
 369         if (!req->rq_repmsg) {
 370                 rc = lustre_pack_reply(req, 0, NULL, NULL);
 371                 if (rc)
 372                         RETURN(rc);
 373         }
 374
 375         req->rq_type = PTL_RPC_MSG_ERR;
 376
 377         rc = ptlrpc_send_reply (req, 0);
 378         RETURN(rc);
 379 }
 380
 381 int ptl_send_rpc(struct ptlrpc_request *request)
 382 {
 383         int rc;
 384         int rc2;
 385         struct ptlrpc_connection *connection;
 386         unsigned long flags;
 387         ptl_handle_me_t  reply_me_h;
 388         ptl_md_t         reply_md;
 389         ENTRY;
 390
 391         LASSERT (request->rq_type == PTL_RPC_MSG_REQUEST);
 392
 393         /* If this is a re-transmit, we're required to have disengaged
 394          * cleanly from the previous attempt */
 395         LASSERT (!request->rq_receiving_reply);
 396
 397         connection = request->rq_import->imp_connection;
 398
 399         if (request->rq_bulk != NULL) {
 400                 rc = ptlrpc_register_bulk (request);
 401                 if (rc != 0)
 402                         RETURN(rc);
 403         }
 404
 405         request->rq_reqmsg->handle = request->rq_import->imp_remote_handle;
 406         request->rq_reqmsg->type = PTL_RPC_MSG_REQUEST;
 407         request->rq_reqmsg->conn_cnt = request->rq_import->imp_conn_cnt;
 408
 409         LASSERT (request->rq_replen != 0);
 410         if (request->rq_repmsg == NULL)
 411                 OBD_ALLOC(request->rq_repmsg, request->rq_replen);
 412         if (request->rq_repmsg == NULL)
 413                 GOTO(cleanup_bulk, rc = -ENOMEM);
 414
 415         rc = PtlMEAttach(connection->c_peer.peer_ni->pni_ni_h,
 416                          request->rq_reply_portal, /* XXX FIXME bug 249 */
 417                          connection->c_peer.peer_id, request->rq_xid, 0, PTL_UNLINK,
 418                          PTL_INS_AFTER, &reply_me_h);
 419         if (rc != PTL_OK) {
 420                 CERROR("PtlMEAttach failed: %d\n", rc);
 421                 LASSERT (rc == PTL_NO_SPACE);
 422                 GOTO(cleanup_repmsg, rc = -ENOMEM);
 423         }
 424
 425         spin_lock_irqsave (&request->rq_lock, flags);
 426         /* If the MD attach succeeds, there _will_ be a reply_in callback */
 427         request->rq_receiving_reply = 1;
 428         /* Clear any flags that may be present from previous sends. */
 429         request->rq_replied = 0;
 430         request->rq_err = 0;
 431         request->rq_timedout = 0;
 432         request->rq_net_err = 0;
 433         request->rq_resend = 0;
 434         request->rq_restart = 0;
 435         spin_unlock_irqrestore (&request->rq_lock, flags);
 436
 437         reply_md.start     = request->rq_repmsg;
 438         reply_md.length    = request->rq_replen;
 439         reply_md.threshold = 1;
 440         reply_md.options   = PTLRPC_MD_OPTIONS | PTL_MD_OP_PUT;
 441         reply_md.user_ptr  = &request->rq_reply_cbid;
 442         reply_md.eventq    = connection->c_peer.peer_ni->pni_eq_h;
 443
 444         rc = PtlMDAttach(reply_me_h, reply_md, PTL_UNLINK,
 445                          &request->rq_reply_md_h);
 446         if (rc != PTL_OK) {
 447                 CERROR("PtlMDAttach failed: %d\n", rc);
 448                 LASSERT (rc == PTL_NO_SPACE);
 449                 GOTO(cleanup_me, rc -ENOMEM);
 450         }
 451
 452         CDEBUG(D_NET, "Setup reply buffer: %u bytes, xid "LPU64
 453                ", portal %u on %s\n",
 454                request->rq_replen, request->rq_xid,
 455                request->rq_reply_portal,
 456                connection->c_peer.peer_ni->pni_name);
 457
 458         ptlrpc_request_addref(request);        /* +1 ref for the SENT callback */
 459
 460         request->rq_sent = LTIME_S(CURRENT_TIME);
 461         ptlrpc_pinger_sending_on_import(request->rq_import);
 462         rc = ptl_send_buf(&request->rq_req_md_h,
 463                           request->rq_reqmsg, request->rq_reqlen,
 464                           PTL_NOACK_REQ, &request->rq_req_cbid,
 465                           connection,
 466                           request->rq_request_portal,
 467                           request->rq_xid);
 468         if (rc == 0) {
 469                 ptlrpc_lprocfs_rpc_sent(request);
 470                 RETURN(rc);
 471         }
 472
 473         ptlrpc_req_finished (request);          /* drop callback ref */
 474
 475  cleanup_me:
 476         /* MEUnlink is safe; the PUT didn't even get off the ground, and
 477          * nobody apart from the PUT's target has the right nid+XID to
 478          * access the reply buffer. */
 479         rc2 = PtlMEUnlink(reply_me_h);
 480         LASSERT (rc2 == PTL_OK);
 481         /* UNLINKED callback called synchronously */
 482         LASSERT (!request->rq_receiving_reply);
 483
 484  cleanup_repmsg:
 485         OBD_FREE(request->rq_repmsg, request->rq_replen);
 486         request->rq_repmsg = NULL;
 487
 488  cleanup_bulk:
 489         if (request->rq_bulk != NULL)
 490                 ptlrpc_unregister_bulk(request);
 491
 492         return rc;
 493 }
 494
 495 int ptlrpc_register_rqbd (struct ptlrpc_request_buffer_desc *rqbd)
 496 {
 497         struct ptlrpc_srv_ni    *srv_ni = rqbd->rqbd_srv_ni;
 498         struct ptlrpc_service   *service = srv_ni->sni_service;
 499         static ptl_process_id_t  match_id = {PTL_NID_ANY, PTL_PID_ANY};
 500         int                      rc;
 501         ptl_md_t                 md;
 502         ptl_handle_me_t          me_h;
 503
 504         CDEBUG(D_NET, "PtlMEAttach: portal %d on %s\n",
 505                service->srv_req_portal, srv_ni->sni_ni->pni_name);
 506
 507         if (OBD_FAIL_CHECK_ONCE(OBD_FAIL_PTLRPC_RQBD))
 508                 return (-ENOMEM);
 509
 510         rc = PtlMEAttach(srv_ni->sni_ni->pni_ni_h, service->srv_req_portal,
 511                          match_id, 0, ~0, PTL_UNLINK, PTL_INS_AFTER, &me_h);
 512         if (rc != PTL_OK) {
 513                 CERROR("PtlMEAttach failed: %d\n", rc);
 514                 return (-ENOMEM);
 515         }
 516
 517         LASSERT(rqbd->rqbd_refcount == 0);
 518         rqbd->rqbd_refcount = 1;
 519
 520         md.start     = rqbd->rqbd_buffer;
 521         md.length    = service->srv_buf_size;
 522         md.max_size  = service->srv_max_req_size;
 523         md.threshold = PTL_MD_THRESH_INF;
 524         md.options   = PTLRPC_MD_OPTIONS | PTL_MD_OP_PUT | PTL_MD_MAX_SIZE;
 525         md.user_ptr  = &rqbd->rqbd_cbid;
 526         md.eventq    = srv_ni->sni_ni->pni_eq_h;
 527
 528         rc = PtlMDAttach(me_h, md, PTL_UNLINK, &rqbd->rqbd_md_h);
 529         if (rc == PTL_OK)
 530                 return (0);
 531
 532         CERROR("PtlMDAttach failed: %d; \n", rc);
 533         LASSERT (rc == PTL_NO_SPACE);
 534         rc = PtlMEUnlink (me_h);
 535         LASSERT (rc == PTL_OK);
 536         rqbd->rqbd_refcount = 0;
 537
 538         return (-ENOMEM);
 539 }