Whamcloud - gitweb
21c13014c5ea86ad44db7764d06d98f5cf49e29e
[fs/lustre-release.git] / lustre / ptlrpc / niobuf.c
1 /*
2  * GPL HEADER START
3  *
4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 only,
8  * as published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it will be useful, but
11  * WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13  * General Public License version 2 for more details (a copy is included
14  * in the LICENSE file that accompanied this code).
15  *
16  * You should have received a copy of the GNU General Public License
17  * version 2 along with this program; If not, see
18  * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
19  *
20  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
21  * CA 95054 USA or visit www.sun.com if you need additional information or
22  * have any questions.
23  *
24  * GPL HEADER END
25  */
26 /*
27  * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
28  * Use is subject to license terms.
29  *
30  * Copyright (c) 2012, 2014, Intel Corporation.
31  */
32 /*
33  * This file is part of Lustre, http://www.lustre.org/
34  * Lustre is a trademark of Sun Microsystems, Inc.
35  */
36
37 #define DEBUG_SUBSYSTEM S_RPC
38 #include <obd_support.h>
39 #include <lustre_net.h>
40 #include <lustre_lib.h>
41 #include <obd.h>
42 #include <obd_class.h>
43 #include "ptlrpc_internal.h"
44
45 /**
46  * Helper function. Sends \a len bytes from \a base at offset \a offset
47  * over \a conn connection to portal \a portal.
48  * Returns 0 on success or error code.
49  */
50 static int ptl_send_buf (lnet_handle_md_t *mdh, void *base, int len,
51                          lnet_ack_req_t ack, struct ptlrpc_cb_id *cbid,
52                          struct ptlrpc_connection *conn, int portal, __u64 xid,
53                          unsigned int offset)
54 {
55         int              rc;
56         lnet_md_t         md;
57         ENTRY;
58
59         LASSERT (portal != 0);
60         LASSERT (conn != NULL);
61         CDEBUG (D_INFO, "conn=%p id %s\n", conn, libcfs_id2str(conn->c_peer));
62         md.start     = base;
63         md.length    = len;
64         md.threshold = (ack == LNET_ACK_REQ) ? 2 : 1;
65         md.options   = PTLRPC_MD_OPTIONS;
66         md.user_ptr  = cbid;
67         md.eq_handle = ptlrpc_eq_h;
68
69         if (unlikely(ack == LNET_ACK_REQ &&
70                      OBD_FAIL_CHECK_ORSET(OBD_FAIL_PTLRPC_ACK, OBD_FAIL_ONCE))){
71                 /* don't ask for the ack to simulate failing client */
72                 ack = LNET_NOACK_REQ;
73         }
74
75         rc = LNetMDBind (md, LNET_UNLINK, mdh);
76         if (unlikely(rc != 0)) {
77                 CERROR ("LNetMDBind failed: %d\n", rc);
78                 LASSERT (rc == -ENOMEM);
79                 RETURN (-ENOMEM);
80         }
81
82         CDEBUG(D_NET, "Sending %d bytes to portal %d, xid "LPD64", offset %u\n",
83                len, portal, xid, offset);
84
85         rc = LNetPut (conn->c_self, *mdh, ack,
86                       conn->c_peer, portal, xid, offset, 0);
87         if (unlikely(rc != 0)) {
88                 int rc2;
89                 /* We're going to get an UNLINK event when I unlink below,
90                  * which will complete just like any other failed send, so
91                  * I fall through and return success here! */
92                 CERROR("LNetPut(%s, %d, "LPD64") failed: %d\n",
93                        libcfs_id2str(conn->c_peer), portal, xid, rc);
94                 rc2 = LNetMDUnlink(*mdh);
95                 LASSERTF(rc2 == 0, "rc2 = %d\n", rc2);
96         }
97
98         RETURN (0);
99 }
100
101 static void mdunlink_iterate_helper(lnet_handle_md_t *bd_mds, int count)
102 {
103         int i;
104
105         for (i = 0; i < count; i++)
106                 LNetMDUnlink(bd_mds[i]);
107 }
108
109 #ifdef HAVE_SERVER_SUPPORT
110 /**
111  * Prepare bulk descriptor for specified incoming request \a req that
112  * can fit \a nfrags * pages. \a type is bulk type. \a portal is where
113  * the bulk to be sent. Used on server-side after request was already
114  * received.
115  * Returns pointer to newly allocatrd initialized bulk descriptor or NULL on
116  * error.
117  */
118 struct ptlrpc_bulk_desc *ptlrpc_prep_bulk_exp(struct ptlrpc_request *req,
119                                               unsigned nfrags, unsigned max_brw,
120                                               unsigned int type,
121                                               unsigned portal,
122                                               const struct ptlrpc_bulk_frag_ops
123                                                 *ops)
124 {
125         struct obd_export *exp = req->rq_export;
126         struct ptlrpc_bulk_desc *desc;
127
128         ENTRY;
129         LASSERT(ptlrpc_is_bulk_op_active(type));
130
131         desc = ptlrpc_new_bulk(nfrags, max_brw, type, portal, ops);
132         if (desc == NULL)
133                 RETURN(NULL);
134
135         desc->bd_export = class_export_get(exp);
136         desc->bd_req = req;
137
138         desc->bd_cbid.cbid_fn  = server_bulk_callback;
139         desc->bd_cbid.cbid_arg = desc;
140
141         /* NB we don't assign rq_bulk here; server-side requests are
142          * re-used, and the handler frees the bulk desc explicitly. */
143
144         return desc;
145 }
146 EXPORT_SYMBOL(ptlrpc_prep_bulk_exp);
147
148 /**
149  * Starts bulk transfer for descriptor \a desc on the server.
150  * Returns 0 on success or error code.
151  */
152 int ptlrpc_start_bulk_transfer(struct ptlrpc_bulk_desc *desc)
153 {
154         struct obd_export        *exp = desc->bd_export;
155         struct ptlrpc_connection *conn = exp->exp_connection;
156         int                       rc = 0;
157         __u64                     xid;
158         int                       posted_md;
159         int                       total_md;
160         lnet_md_t                 md;
161         ENTRY;
162
163         if (OBD_FAIL_CHECK(OBD_FAIL_PTLRPC_BULK_PUT_NET))
164                 RETURN(0);
165
166         /* NB no locking required until desc is on the network */
167         LASSERT(desc->bd_md_count == 0);
168         LASSERT(ptlrpc_is_bulk_op_active(desc->bd_type));
169
170         LASSERT(desc->bd_cbid.cbid_fn == server_bulk_callback);
171         LASSERT(desc->bd_cbid.cbid_arg == desc);
172
173         /* NB total length may be 0 for a read past EOF, so we send 0
174          * length bulks, since the client expects bulk events.
175          *
176          * The client may not need all of the bulk XIDs for the RPC.  The RPC
177          * used the XID of the highest bulk XID needed, and the server masks
178          * off high bits to get bulk count for this RPC. LU-1431 */
179         xid = desc->bd_req->rq_xid & ~((__u64)desc->bd_md_max_brw - 1);
180         total_md = desc->bd_req->rq_xid - xid + 1;
181
182         desc->bd_md_count = total_md;
183         desc->bd_failure = 0;
184
185         md.user_ptr = &desc->bd_cbid;
186         md.eq_handle = ptlrpc_eq_h;
187         md.threshold = 2; /* SENT and ACK/REPLY */
188
189         for (posted_md = 0; posted_md < total_md; xid++) {
190                 md.options = PTLRPC_MD_OPTIONS;
191
192                 /* NB it's assumed that source and sink buffer frags are
193                  * page-aligned. Otherwise we'd have to send client bulk
194                  * sizes over and split server buffer accordingly */
195                 ptlrpc_fill_bulk_md(&md, desc, posted_md);
196                 rc = LNetMDBind(md, LNET_UNLINK, &desc->bd_mds[posted_md]);
197                 if (rc != 0) {
198                         CERROR("%s: LNetMDBind failed for MD %u: rc = %d\n",
199                                exp->exp_obd->obd_name, posted_md, rc);
200                         LASSERT(rc == -ENOMEM);
201                         if (posted_md == 0) {
202                                 desc->bd_md_count = 0;
203                                 RETURN(-ENOMEM);
204                         }
205                         break;
206                 }
207
208                 /* LU-6441: last md is not sent and desc->bd_md_count == 1 */
209                 if (OBD_FAIL_CHECK_ORSET(OBD_FAIL_PTLRPC_CLIENT_BULK_CB3,
210                                          CFS_FAIL_ONCE) &&
211                     posted_md == desc->bd_md_max_brw - 1) {
212                         posted_md++;
213                         continue;
214                 }
215
216                 /* Network is about to get at the memory */
217                 if (ptlrpc_is_bulk_put_source(desc->bd_type))
218                         rc = LNetPut(conn->c_self, desc->bd_mds[posted_md],
219                                      LNET_ACK_REQ, conn->c_peer,
220                                      desc->bd_portal, xid, 0, 0);
221                 else
222                         rc = LNetGet(conn->c_self, desc->bd_mds[posted_md],
223                                      conn->c_peer, desc->bd_portal, xid, 0);
224
225                 posted_md++;
226                 if (rc != 0) {
227                         CERROR("%s: failed bulk transfer with %s:%u x"LPU64": "
228                                "rc = %d\n", exp->exp_obd->obd_name,
229                                libcfs_id2str(conn->c_peer), desc->bd_portal,
230                                xid, rc);
231                         break;
232                 }
233         }
234
235         if (rc != 0) {
236                 /* Can't send, so we unlink the MD bound above.  The UNLINK
237                  * event this creates will signal completion with failure,
238                  * so we return SUCCESS here! */
239                 spin_lock(&desc->bd_lock);
240                 desc->bd_md_count -= total_md - posted_md;
241                 spin_unlock(&desc->bd_lock);
242                 LASSERT(desc->bd_md_count >= 0);
243
244                 mdunlink_iterate_helper(desc->bd_mds, posted_md);
245                 RETURN(0);
246         }
247
248         CDEBUG(D_NET, "Transferring %u pages %u bytes via portal %d "
249                "id %s xid "LPX64"-"LPX64"\n", desc->bd_iov_count,
250                desc->bd_nob, desc->bd_portal, libcfs_id2str(conn->c_peer),
251                xid - posted_md, xid - 1);
252
253         RETURN(0);
254 }
255
256 /**
257  * Server side bulk abort. Idempotent. Not thread-safe (i.e. only
258  * serialises with completion callback)
259  */
260 void ptlrpc_abort_bulk(struct ptlrpc_bulk_desc *desc)
261 {
262         struct l_wait_info       lwi;
263         int                      rc;
264
265         LASSERT(!in_interrupt());           /* might sleep */
266
267         if (!ptlrpc_server_bulk_active(desc))   /* completed or */
268                 return;                         /* never started */
269
270         /* We used to poison the pages with 0xab here because we did not want to
271          * send any meaningful data over the wire for evicted clients (bug 9297)
272          * However, this is no longer safe now that we use the page cache on the
273          * OSS (bug 20560) */
274
275         /* The unlink ensures the callback happens ASAP and is the last
276          * one.  If it fails, it must be because completion just happened,
277          * but we must still l_wait_event() in this case, to give liblustre
278          * a chance to run server_bulk_callback()*/
279         mdunlink_iterate_helper(desc->bd_mds, desc->bd_md_max_brw);
280
281         for (;;) {
282                 /* Network access will complete in finite time but the HUGE
283                  * timeout lets us CWARN for visibility of sluggish NALs */
284                 lwi = LWI_TIMEOUT_INTERVAL(cfs_time_seconds(LONG_UNLINK),
285                                            cfs_time_seconds(1), NULL, NULL);
286                 rc = l_wait_event(desc->bd_waitq,
287                                   !ptlrpc_server_bulk_active(desc), &lwi);
288                 if (rc == 0)
289                         return;
290
291                 LASSERT(rc == -ETIMEDOUT);
292                 CWARN("Unexpectedly long timeout: desc %p\n", desc);
293         }
294 }
295 #endif /* HAVE_SERVER_SUPPORT */
296
297 /**
298  * Register bulk at the sender for later transfer.
299  * Returns 0 on success or error code.
300  */
301 int ptlrpc_register_bulk(struct ptlrpc_request *req)
302 {
303         struct ptlrpc_bulk_desc *desc = req->rq_bulk;
304         lnet_process_id_t peer;
305         int rc = 0;
306         int rc2;
307         int posted_md;
308         int total_md;
309         __u64 xid;
310         lnet_handle_me_t  me_h;
311         lnet_md_t         md;
312         ENTRY;
313
314         if (OBD_FAIL_CHECK(OBD_FAIL_PTLRPC_BULK_GET_NET))
315                 RETURN(0);
316
317         /* NB no locking required until desc is on the network */
318         LASSERT(desc->bd_nob > 0);
319         LASSERT(desc->bd_md_count == 0);
320         LASSERT(desc->bd_md_max_brw <= PTLRPC_BULK_OPS_COUNT);
321         LASSERT(desc->bd_iov_count <= PTLRPC_MAX_BRW_PAGES);
322         LASSERT(desc->bd_req != NULL);
323         LASSERT(ptlrpc_is_bulk_op_passive(desc->bd_type));
324
325         /* cleanup the state of the bulk for it will be reused */
326         if (req->rq_resend || req->rq_send_state == LUSTRE_IMP_REPLAY)
327                 desc->bd_nob_transferred = 0;
328         else
329                 LASSERT(desc->bd_nob_transferred == 0);
330
331         desc->bd_failure = 0;
332
333         peer = desc->bd_import->imp_connection->c_peer;
334
335         LASSERT(desc->bd_cbid.cbid_fn == client_bulk_callback);
336         LASSERT(desc->bd_cbid.cbid_arg == desc);
337
338         /* An XID is only used for a single request from the client.
339          * For retried bulk transfers, a new XID will be allocated in
340          * in ptlrpc_check_set() if it needs to be resent, so it is not
341          * using the same RDMA match bits after an error.
342          *
343          * For multi-bulk RPCs, rq_xid is the last XID needed for bulks. The
344          * first bulk XID is power-of-two aligned before rq_xid. LU-1431 */
345         xid = req->rq_xid & ~((__u64)desc->bd_md_max_brw - 1);
346         LASSERTF(!(desc->bd_registered &&
347                    req->rq_send_state != LUSTRE_IMP_REPLAY) ||
348                  xid != desc->bd_last_xid,
349                  "registered: %d  rq_xid: "LPU64" bd_last_xid: "LPU64"\n",
350                  desc->bd_registered, xid, desc->bd_last_xid);
351
352         total_md = (desc->bd_iov_count + LNET_MAX_IOV - 1) / LNET_MAX_IOV;
353         desc->bd_registered = 1;
354         desc->bd_last_xid = xid;
355         desc->bd_md_count = total_md;
356         md.user_ptr = &desc->bd_cbid;
357         md.eq_handle = ptlrpc_eq_h;
358         md.threshold = 1;                       /* PUT or GET */
359
360         for (posted_md = 0; posted_md < total_md; posted_md++, xid++) {
361                 md.options = PTLRPC_MD_OPTIONS |
362                              (ptlrpc_is_bulk_op_get(desc->bd_type) ?
363                               LNET_MD_OP_GET : LNET_MD_OP_PUT);
364                 ptlrpc_fill_bulk_md(&md, desc, posted_md);
365
366                 rc = LNetMEAttach(desc->bd_portal, peer, xid, 0,
367                                   LNET_UNLINK, LNET_INS_AFTER, &me_h);
368                 if (rc != 0) {
369                         CERROR("%s: LNetMEAttach failed x"LPU64"/%d: rc = %d\n",
370                                desc->bd_import->imp_obd->obd_name, xid,
371                                posted_md, rc);
372                         break;
373                 }
374
375                 /* About to let the network at it... */
376                 rc = LNetMDAttach(me_h, md, LNET_UNLINK,
377                                   &desc->bd_mds[posted_md]);
378                 if (rc != 0) {
379                         CERROR("%s: LNetMDAttach failed x"LPU64"/%d: rc = %d\n",
380                                desc->bd_import->imp_obd->obd_name, xid,
381                                posted_md, rc);
382                         rc2 = LNetMEUnlink(me_h);
383                         LASSERT(rc2 == 0);
384                         break;
385                 }
386         }
387
388         if (rc != 0) {
389                 LASSERT(rc == -ENOMEM);
390                 spin_lock(&desc->bd_lock);
391                 desc->bd_md_count -= total_md - posted_md;
392                 spin_unlock(&desc->bd_lock);
393                 LASSERT(desc->bd_md_count >= 0);
394                 mdunlink_iterate_helper(desc->bd_mds, desc->bd_md_max_brw);
395                 req->rq_status = -ENOMEM;
396                 RETURN(-ENOMEM);
397         }
398
399         /* Set rq_xid to matchbits of the final bulk so that server can
400          * infer the number of bulks that were prepared */
401         req->rq_xid = --xid;
402         LASSERTF(desc->bd_last_xid == (req->rq_xid & PTLRPC_BULK_OPS_MASK),
403                  "bd_last_xid = x"LPU64", rq_xid = x"LPU64"\n",
404                  desc->bd_last_xid, req->rq_xid);
405
406         spin_lock(&desc->bd_lock);
407         /* Holler if peer manages to touch buffers before he knows the xid */
408         if (desc->bd_md_count != total_md)
409                 CWARN("%s: Peer %s touched %d buffers while I registered\n",
410                       desc->bd_import->imp_obd->obd_name, libcfs_id2str(peer),
411                       total_md - desc->bd_md_count);
412         spin_unlock(&desc->bd_lock);
413
414         CDEBUG(D_NET, "Setup %u bulk %s buffers: %u pages %u bytes, "
415                "xid x"LPX64"-"LPX64", portal %u\n", desc->bd_md_count,
416                ptlrpc_is_bulk_op_get(desc->bd_type) ? "get-source" : "put-sink",
417                desc->bd_iov_count, desc->bd_nob,
418                desc->bd_last_xid, req->rq_xid, desc->bd_portal);
419
420         RETURN(0);
421 }
422
423 /**
424  * Disconnect a bulk desc from the network. Idempotent. Not
425  * thread-safe (i.e. only interlocks with completion callback).
426  * Returns 1 on success or 0 if network unregistration failed for whatever
427  * reason.
428  */
429 int ptlrpc_unregister_bulk(struct ptlrpc_request *req, int async)
430 {
431         struct ptlrpc_bulk_desc *desc = req->rq_bulk;
432         struct l_wait_info       lwi;
433         int                      rc;
434         ENTRY;
435
436         LASSERT(!in_interrupt());     /* might sleep */
437
438         /* Let's setup deadline for reply unlink. */
439         if (OBD_FAIL_CHECK(OBD_FAIL_PTLRPC_LONG_BULK_UNLINK) &&
440             async && req->rq_bulk_deadline == 0)
441                 req->rq_bulk_deadline = cfs_time_current_sec() + LONG_UNLINK;
442
443         if (ptlrpc_client_bulk_active(req) == 0)        /* completed or */
444                 RETURN(1);                              /* never registered */
445
446         LASSERT(desc->bd_req == req);  /* bd_req NULL until registered */
447
448         /* the unlink ensures the callback happens ASAP and is the last
449          * one.  If it fails, it must be because completion just happened,
450          * but we must still l_wait_event() in this case to give liblustre
451          * a chance to run client_bulk_callback() */
452         mdunlink_iterate_helper(desc->bd_mds, desc->bd_md_max_brw);
453
454         if (ptlrpc_client_bulk_active(req) == 0)        /* completed or */
455                 RETURN(1);                              /* never registered */
456
457         /* Move to "Unregistering" phase as bulk was not unlinked yet. */
458         ptlrpc_rqphase_move(req, RQ_PHASE_UNREGISTERING);
459
460         /* Do not wait for unlink to finish. */
461         if (async)
462                 RETURN(0);
463
464         for (;;) {
465                 /* The wq argument is ignored by user-space wait_event macros */
466                 wait_queue_head_t *wq = (req->rq_set != NULL) ?
467                                         &req->rq_set->set_waitq :
468                                         &req->rq_reply_waitq;
469                 /* Network access will complete in finite time but the HUGE
470                  * timeout lets us CWARN for visibility of sluggish NALs */
471                 lwi = LWI_TIMEOUT_INTERVAL(cfs_time_seconds(LONG_UNLINK),
472                                            cfs_time_seconds(1), NULL, NULL);
473                 rc = l_wait_event(*wq, !ptlrpc_client_bulk_active(req), &lwi);
474                 if (rc == 0) {
475                         ptlrpc_rqphase_move(req, req->rq_next_phase);
476                         RETURN(1);
477                 }
478
479                 LASSERT(rc == -ETIMEDOUT);
480                 DEBUG_REQ(D_WARNING, req, "Unexpectedly long timeout: desc %p",
481                           desc);
482         }
483         RETURN(0);
484 }
485
486 static void ptlrpc_at_set_reply(struct ptlrpc_request *req, int flags)
487 {
488         struct ptlrpc_service_part      *svcpt = req->rq_rqbd->rqbd_svcpt;
489         struct ptlrpc_service           *svc = svcpt->scp_service;
490         int service_time = max_t(int, cfs_time_current_sec() -
491                                  req->rq_arrival_time.tv_sec, 1);
492
493         if (!(flags & PTLRPC_REPLY_EARLY) &&
494             (req->rq_type != PTL_RPC_MSG_ERR) &&
495             (req->rq_reqmsg != NULL) &&
496             !(lustre_msg_get_flags(req->rq_reqmsg) &
497               (MSG_RESENT | MSG_REPLAY |
498                MSG_REQ_REPLAY_DONE | MSG_LOCK_REPLAY_DONE))) {
499                 /* early replies, errors and recovery requests don't count
500                  * toward our service time estimate */
501                 int oldse = at_measured(&svcpt->scp_at_estimate, service_time);
502
503                 if (oldse != 0) {
504                         DEBUG_REQ(D_ADAPTTO, req,
505                                   "svc %s changed estimate from %d to %d",
506                                   svc->srv_name, oldse,
507                                   at_get(&svcpt->scp_at_estimate));
508                 }
509         }
510         /* Report actual service time for client latency calc */
511         lustre_msg_set_service_time(req->rq_repmsg, service_time);
512         /* Report service time estimate for future client reqs, but report 0
513          * (to be ignored by client) if it's an error reply during recovery.
514          * (bz15815) */
515         if (req->rq_type == PTL_RPC_MSG_ERR &&
516             (req->rq_export == NULL || req->rq_export->exp_obd->obd_recovering))
517                 lustre_msg_set_timeout(req->rq_repmsg, 0);
518         else
519                 lustre_msg_set_timeout(req->rq_repmsg,
520                                        at_get(&svcpt->scp_at_estimate));
521
522         if (req->rq_reqmsg &&
523             !(lustre_msghdr_get_flags(req->rq_reqmsg) & MSGHDR_AT_SUPPORT)) {
524                 CDEBUG(D_ADAPTTO, "No early reply support: flags=%#x "
525                        "req_flags=%#x magic=%x/%x len=%d\n",
526                        flags, lustre_msg_get_flags(req->rq_reqmsg),
527                        lustre_msg_get_magic(req->rq_reqmsg),
528                        lustre_msg_get_magic(req->rq_repmsg), req->rq_replen);
529         }
530 }
531
532 /**
533  * Send request reply from request \a req reply buffer.
534  * \a flags defines reply types
535  * Returns 0 on success or error code
536  */
537 int ptlrpc_send_reply(struct ptlrpc_request *req, int flags)
538 {
539         struct ptlrpc_reply_state *rs = req->rq_reply_state;
540         struct ptlrpc_connection  *conn;
541         int                        rc;
542
543         /* We must already have a reply buffer (only ptlrpc_error() may be
544          * called without one). The reply generated by sptlrpc layer (e.g.
545          * error notify, etc.) might have NULL rq->reqmsg; Otherwise we must
546          * have a request buffer which is either the actual (swabbed) incoming
547          * request, or a saved copy if this is a req saved in
548          * target_queue_final_reply().
549          */
550         LASSERT (req->rq_no_reply == 0);
551         LASSERT (req->rq_reqbuf != NULL);
552         LASSERT (rs != NULL);
553         LASSERT ((flags & PTLRPC_REPLY_MAYBE_DIFFICULT) || !rs->rs_difficult);
554         LASSERT (req->rq_repmsg != NULL);
555         LASSERT (req->rq_repmsg == rs->rs_msg);
556         LASSERT (rs->rs_cb_id.cbid_fn == reply_out_callback);
557         LASSERT (rs->rs_cb_id.cbid_arg == rs);
558
559         /* There may be no rq_export during failover */
560
561         if (unlikely(req->rq_export && req->rq_export->exp_obd &&
562                      req->rq_export->exp_obd->obd_fail)) {
563                 /* Failed obd's only send ENODEV */
564                 req->rq_type = PTL_RPC_MSG_ERR;
565                 req->rq_status = -ENODEV;
566                 CDEBUG(D_HA, "sending ENODEV from failed obd %d\n",
567                        req->rq_export->exp_obd->obd_minor);
568         }
569
570         /* In order to keep interoprability with the client (< 2.3) which
571          * doesn't have pb_jobid in ptlrpc_body, We have to shrink the
572          * ptlrpc_body in reply buffer to ptlrpc_body_v2, otherwise, the
573          * reply buffer on client will be overflow.
574          *
575          * XXX Remove this whenver we drop the interoprability with such client.
576          */
577         req->rq_replen = lustre_shrink_msg(req->rq_repmsg, 0,
578                                            sizeof(struct ptlrpc_body_v2), 1);
579
580         if (req->rq_type != PTL_RPC_MSG_ERR)
581                 req->rq_type = PTL_RPC_MSG_REPLY;
582
583         lustre_msg_set_type(req->rq_repmsg, req->rq_type);
584         lustre_msg_set_status(req->rq_repmsg,
585                               ptlrpc_status_hton(req->rq_status));
586         lustre_msg_set_opc(req->rq_repmsg,
587                 req->rq_reqmsg ? lustre_msg_get_opc(req->rq_reqmsg) : 0);
588
589         target_pack_pool_reply(req);
590
591         ptlrpc_at_set_reply(req, flags);
592
593         if (req->rq_export == NULL || req->rq_export->exp_connection == NULL)
594                 conn = ptlrpc_connection_get(req->rq_peer, req->rq_self, NULL);
595         else
596                 conn = ptlrpc_connection_addref(req->rq_export->exp_connection);
597
598         if (unlikely(conn == NULL)) {
599                 CERROR("not replying on NULL connection\n"); /* bug 9635 */
600                 return -ENOTCONN;
601         }
602         ptlrpc_rs_addref(rs);                   /* +1 ref for the network */
603
604         rc = sptlrpc_svc_wrap_reply(req);
605         if (unlikely(rc))
606                 goto out;
607
608         req->rq_sent = cfs_time_current_sec();
609
610         rc = ptl_send_buf (&rs->rs_md_h, rs->rs_repbuf, rs->rs_repdata_len,
611                            (rs->rs_difficult && !rs->rs_no_ack) ?
612                            LNET_ACK_REQ : LNET_NOACK_REQ,
613                            &rs->rs_cb_id, conn,
614                            ptlrpc_req2svc(req)->srv_rep_portal,
615                            req->rq_xid, req->rq_reply_off);
616 out:
617         if (unlikely(rc != 0))
618                 ptlrpc_req_drop_rs(req);
619         ptlrpc_connection_put(conn);
620         return rc;
621 }
622
623 int ptlrpc_reply (struct ptlrpc_request *req)
624 {
625         if (req->rq_no_reply)
626                 return 0;
627         else
628                 return (ptlrpc_send_reply(req, 0));
629 }
630
631 /**
632  * For request \a req send an error reply back. Create empty
633  * reply buffers if necessary.
634  */
635 int ptlrpc_send_error(struct ptlrpc_request *req, int may_be_difficult)
636 {
637         int rc;
638         ENTRY;
639
640         if (req->rq_no_reply)
641                 RETURN(0);
642
643         if (!req->rq_repmsg) {
644                 rc = lustre_pack_reply(req, 1, NULL, NULL);
645                 if (rc)
646                         RETURN(rc);
647         }
648
649         if (req->rq_status != -ENOSPC && req->rq_status != -EACCES &&
650             req->rq_status != -EPERM && req->rq_status != -ENOENT &&
651             req->rq_status != -EINPROGRESS && req->rq_status != -EDQUOT)
652                 req->rq_type = PTL_RPC_MSG_ERR;
653
654         rc = ptlrpc_send_reply(req, may_be_difficult);
655         RETURN(rc);
656 }
657
658 int ptlrpc_error(struct ptlrpc_request *req)
659 {
660         return ptlrpc_send_error(req, 0);
661 }
662
663 /**
664  * Send request \a request.
665  * if \a noreply is set, don't expect any reply back and don't set up
666  * reply buffers.
667  * Returns 0 on success or error code.
668  */
669 int ptl_send_rpc(struct ptlrpc_request *request, int noreply)
670 {
671         int rc;
672         int rc2;
673         int mpflag = 0;
674         struct ptlrpc_connection *connection;
675         lnet_handle_me_t  reply_me_h;
676         lnet_md_t         reply_md;
677         struct obd_import *imp = request->rq_import;
678         struct obd_device *obd = imp->imp_obd;
679         ENTRY;
680
681         if (OBD_FAIL_CHECK(OBD_FAIL_PTLRPC_DROP_RPC))
682                 RETURN(0);
683
684         LASSERT(request->rq_type == PTL_RPC_MSG_REQUEST);
685         LASSERT(request->rq_wait_ctx == 0);
686
687         /* If this is a re-transmit, we're required to have disengaged
688          * cleanly from the previous attempt */
689         LASSERT(!request->rq_receiving_reply);
690         LASSERT(!((lustre_msg_get_flags(request->rq_reqmsg) & MSG_REPLAY) &&
691                 (imp->imp_state == LUSTRE_IMP_FULL)));
692
693         if (unlikely(obd != NULL && obd->obd_fail)) {
694                 CDEBUG(D_HA, "muting rpc for failed imp obd %s\n",
695                         obd->obd_name);
696                 /* this prevents us from waiting in ptlrpc_queue_wait */
697                 spin_lock(&request->rq_lock);
698                 request->rq_err = 1;
699                 spin_unlock(&request->rq_lock);
700                 request->rq_status = -ENODEV;
701                 RETURN(-ENODEV);
702         }
703
704         connection = imp->imp_connection;
705
706         lustre_msg_set_handle(request->rq_reqmsg,
707                               &imp->imp_remote_handle);
708         lustre_msg_set_type(request->rq_reqmsg, PTL_RPC_MSG_REQUEST);
709         lustre_msg_set_conn_cnt(request->rq_reqmsg,
710                                 imp->imp_conn_cnt);
711         lustre_msghdr_set_flags(request->rq_reqmsg,
712                                 imp->imp_msghdr_flags);
713
714         /** For enabled AT all request should have AT_SUPPORT in the
715          * FULL import state when OBD_CONNECT_AT is set */
716         LASSERT(AT_OFF || imp->imp_state != LUSTRE_IMP_FULL ||
717                 (imp->imp_msghdr_flags & MSGHDR_AT_SUPPORT) ||
718                 !(imp->imp_connect_data.ocd_connect_flags &
719                 OBD_CONNECT_AT));
720
721         if (request->rq_resend) {
722                 lustre_msg_add_flags(request->rq_reqmsg, MSG_RESENT);
723                 if (request->rq_resend_cb != NULL)
724                         request->rq_resend_cb(request, &request->rq_async_args);
725         }
726         if (request->rq_memalloc)
727                 mpflag = cfs_memory_pressure_get_and_set();
728
729         rc = sptlrpc_cli_wrap_request(request);
730         if (rc)
731                 GOTO(out, rc);
732
733         /* bulk register should be done after wrap_request() */
734         if (request->rq_bulk != NULL) {
735                 rc = ptlrpc_register_bulk (request);
736                 if (rc != 0)
737                         GOTO(out, rc);
738         }
739
740         if (!noreply) {
741                 LASSERT (request->rq_replen != 0);
742                 if (request->rq_repbuf == NULL) {
743                         LASSERT(request->rq_repdata == NULL);
744                         LASSERT(request->rq_repmsg == NULL);
745                         rc = sptlrpc_cli_alloc_repbuf(request,
746                                                       request->rq_replen);
747                         if (rc) {
748                                 /* this prevents us from looping in
749                                  * ptlrpc_queue_wait */
750                                 spin_lock(&request->rq_lock);
751                                 request->rq_err = 1;
752                                 spin_unlock(&request->rq_lock);
753                                 request->rq_status = rc;
754                                 GOTO(cleanup_bulk, rc);
755                         }
756                 } else {
757                         request->rq_repdata = NULL;
758                         request->rq_repmsg = NULL;
759                 }
760
761                 rc = LNetMEAttach(request->rq_reply_portal,/*XXX FIXME bug 249*/
762                                   connection->c_peer, request->rq_xid, 0,
763                                   LNET_UNLINK, LNET_INS_AFTER, &reply_me_h);
764                 if (rc != 0) {
765                         CERROR("LNetMEAttach failed: %d\n", rc);
766                         LASSERT (rc == -ENOMEM);
767                         GOTO(cleanup_bulk, rc = -ENOMEM);
768                 }
769         }
770
771         spin_lock(&request->rq_lock);
772         /* We are responsible for unlinking the reply buffer */
773         request->rq_reply_unlinked = noreply;
774         request->rq_receiving_reply = !noreply;
775         /* Clear any flags that may be present from previous sends. */
776         request->rq_req_unlinked = 0;
777         request->rq_replied = 0;
778         request->rq_err = 0;
779         request->rq_timedout = 0;
780         request->rq_net_err = 0;
781         request->rq_resend = 0;
782         request->rq_restart = 0;
783         request->rq_reply_truncated = 0;
784         spin_unlock(&request->rq_lock);
785
786         if (!noreply) {
787                 reply_md.start     = request->rq_repbuf;
788                 reply_md.length    = request->rq_repbuf_len;
789                 /* Allow multiple early replies */
790                 reply_md.threshold = LNET_MD_THRESH_INF;
791                 /* Manage remote for early replies */
792                 reply_md.options   = PTLRPC_MD_OPTIONS | LNET_MD_OP_PUT |
793                         LNET_MD_MANAGE_REMOTE |
794                         LNET_MD_TRUNCATE; /* allow to make EOVERFLOW error */;
795                 reply_md.user_ptr  = &request->rq_reply_cbid;
796                 reply_md.eq_handle = ptlrpc_eq_h;
797
798                 /* We must see the unlink callback to set rq_reply_unlinked,
799                  * so we can't auto-unlink */
800                 rc = LNetMDAttach(reply_me_h, reply_md, LNET_RETAIN,
801                                   &request->rq_reply_md_h);
802                 if (rc != 0) {
803                         CERROR("LNetMDAttach failed: %d\n", rc);
804                         LASSERT (rc == -ENOMEM);
805                         spin_lock(&request->rq_lock);
806                         /* ...but the MD attach didn't succeed... */
807                         request->rq_receiving_reply = 0;
808                         spin_unlock(&request->rq_lock);
809                         GOTO(cleanup_me, rc = -ENOMEM);
810                 }
811
812                 CDEBUG(D_NET, "Setup reply buffer: %u bytes, xid "LPU64
813                        ", portal %u\n",
814                        request->rq_repbuf_len, request->rq_xid,
815                        request->rq_reply_portal);
816         }
817
818         /* add references on request for request_out_callback */
819         ptlrpc_request_addref(request);
820         if (obd != NULL && obd->obd_svc_stats != NULL)
821                 lprocfs_counter_add(obd->obd_svc_stats, PTLRPC_REQACTIVE_CNTR,
822                         atomic_read(&imp->imp_inflight));
823
824         OBD_FAIL_TIMEOUT(OBD_FAIL_PTLRPC_DELAY_SEND, request->rq_timeout + 5);
825
826         do_gettimeofday(&request->rq_sent_tv);
827         request->rq_sent = cfs_time_current_sec();
828         /* We give the server rq_timeout secs to process the req, and
829            add the network latency for our local timeout. */
830         request->rq_deadline = request->rq_sent + request->rq_timeout +
831                 ptlrpc_at_get_net_latency(request);
832
833         ptlrpc_pinger_sending_on_import(imp);
834
835         DEBUG_REQ(D_INFO, request, "send flg=%x",
836                   lustre_msg_get_flags(request->rq_reqmsg));
837         rc = ptl_send_buf(&request->rq_req_md_h,
838                           request->rq_reqbuf, request->rq_reqdata_len,
839                           LNET_NOACK_REQ, &request->rq_req_cbid,
840                           connection,
841                           request->rq_request_portal,
842                           request->rq_xid, 0);
843         if (likely(rc == 0))
844                 GOTO(out, rc);
845
846         request->rq_req_unlinked = 1;
847         ptlrpc_req_finished(request);
848         if (noreply)
849                 GOTO(out, rc);
850
851  cleanup_me:
852         /* MEUnlink is safe; the PUT didn't even get off the ground, and
853          * nobody apart from the PUT's target has the right nid+XID to
854          * access the reply buffer. */
855         rc2 = LNetMEUnlink(reply_me_h);
856         LASSERT (rc2 == 0);
857         /* UNLINKED callback called synchronously */
858         LASSERT(!request->rq_receiving_reply);
859
860  cleanup_bulk:
861         /* We do sync unlink here as there was no real transfer here so
862          * the chance to have long unlink to sluggish net is smaller here. */
863         ptlrpc_unregister_bulk(request, 0);
864  out:
865         if (request->rq_memalloc)
866                 cfs_memory_pressure_restore(mpflag);
867         return rc;
868 }
869 EXPORT_SYMBOL(ptl_send_rpc);
870
871 /**
872  * Register request buffer descriptor for request receiving.
873  */
874 int ptlrpc_register_rqbd(struct ptlrpc_request_buffer_desc *rqbd)
875 {
876         struct ptlrpc_service     *service = rqbd->rqbd_svcpt->scp_service;
877         static lnet_process_id_t  match_id = {LNET_NID_ANY, LNET_PID_ANY};
878         int                       rc;
879         lnet_md_t                 md;
880         lnet_handle_me_t          me_h;
881
882         CDEBUG(D_NET, "LNetMEAttach: portal %d\n",
883                service->srv_req_portal);
884
885         if (OBD_FAIL_CHECK(OBD_FAIL_PTLRPC_RQBD))
886                 return (-ENOMEM);
887
888         /* NB: CPT affinity service should use new LNet flag LNET_INS_LOCAL,
889          * which means buffer can only be attached on local CPT, and LND
890          * threads can find it by grabbing a local lock */
891         rc = LNetMEAttach(service->srv_req_portal,
892                           match_id, 0, ~0, LNET_UNLINK,
893                           rqbd->rqbd_svcpt->scp_cpt >= 0 ?
894                           LNET_INS_LOCAL : LNET_INS_AFTER, &me_h);
895         if (rc != 0) {
896                 CERROR("LNetMEAttach failed: %d\n", rc);
897                 return (-ENOMEM);
898         }
899
900         LASSERT(rqbd->rqbd_refcount == 0);
901         rqbd->rqbd_refcount = 1;
902
903         md.start     = rqbd->rqbd_buffer;
904         md.length    = service->srv_buf_size;
905         md.max_size  = service->srv_max_req_size;
906         md.threshold = LNET_MD_THRESH_INF;
907         md.options   = PTLRPC_MD_OPTIONS | LNET_MD_OP_PUT | LNET_MD_MAX_SIZE;
908         md.user_ptr  = &rqbd->rqbd_cbid;
909         md.eq_handle = ptlrpc_eq_h;
910
911         rc = LNetMDAttach(me_h, md, LNET_UNLINK, &rqbd->rqbd_md_h);
912         if (rc == 0)
913                 return (0);
914
915         CERROR("LNetMDAttach failed: %d; \n", rc);
916         LASSERT (rc == -ENOMEM);
917         rc = LNetMEUnlink (me_h);
918         LASSERT (rc == 0);
919         rqbd->rqbd_refcount = 0;
920
921         return (-ENOMEM);
922 }