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LU-5710 all: second batch of corrected typos and grammar errors
[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 npages * 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 npages, unsigned max_brw,
120                                               unsigned type, unsigned portal)
121 {
122         struct obd_export *exp = req->rq_export;
123         struct ptlrpc_bulk_desc *desc;
124
125         ENTRY;
126         LASSERT(type == BULK_PUT_SOURCE || type == BULK_GET_SINK);
127
128         desc = ptlrpc_new_bulk(npages, max_brw, type, portal);
129         if (desc == NULL)
130                 RETURN(NULL);
131
132         desc->bd_export = class_export_get(exp);
133         desc->bd_req = req;
134
135         desc->bd_cbid.cbid_fn  = server_bulk_callback;
136         desc->bd_cbid.cbid_arg = desc;
137
138         /* NB we don't assign rq_bulk here; server-side requests are
139          * re-used, and the handler frees the bulk desc explicitly. */
140
141         return desc;
142 }
143 EXPORT_SYMBOL(ptlrpc_prep_bulk_exp);
144
145 /**
146  * Starts bulk transfer for descriptor \a desc on the server.
147  * Returns 0 on success or error code.
148  */
149 int ptlrpc_start_bulk_transfer(struct ptlrpc_bulk_desc *desc)
150 {
151         struct obd_export        *exp = desc->bd_export;
152         struct ptlrpc_connection *conn = exp->exp_connection;
153         int                       rc = 0;
154         __u64                     xid;
155         int                       posted_md;
156         int                       total_md;
157         lnet_md_t                 md;
158         ENTRY;
159
160         if (OBD_FAIL_CHECK(OBD_FAIL_PTLRPC_BULK_PUT_NET))
161                 RETURN(0);
162
163         /* NB no locking required until desc is on the network */
164         LASSERT(desc->bd_md_count == 0);
165         LASSERT(desc->bd_type == BULK_PUT_SOURCE ||
166                 desc->bd_type == BULK_GET_SINK);
167
168         LASSERT(desc->bd_cbid.cbid_fn == server_bulk_callback);
169         LASSERT(desc->bd_cbid.cbid_arg == desc);
170
171         /* NB total length may be 0 for a read past EOF, so we send 0
172          * length bulks, since the client expects bulk events.
173          *
174          * The client may not need all of the bulk XIDs for the RPC.  The RPC
175          * used the XID of the highest bulk XID needed, and the server masks
176          * off high bits to get bulk count for this RPC. LU-1431 */
177         xid = desc->bd_req->rq_xid & ~((__u64)desc->bd_md_max_brw - 1);
178         total_md = desc->bd_req->rq_xid - xid + 1;
179
180         desc->bd_md_count = total_md;
181         desc->bd_failure = 0;
182
183         md.user_ptr = &desc->bd_cbid;
184         md.eq_handle = ptlrpc_eq_h;
185         md.threshold = 2; /* SENT and ACK/REPLY */
186
187         for (posted_md = 0; posted_md < total_md; xid++) {
188                 md.options = PTLRPC_MD_OPTIONS;
189
190                 /* NB it's assumed that source and sink buffer frags are
191                  * page-aligned. Otherwise we'd have to send client bulk
192                  * sizes over and split server buffer accordingly */
193                 ptlrpc_fill_bulk_md(&md, desc, posted_md);
194                 rc = LNetMDBind(md, LNET_UNLINK, &desc->bd_mds[posted_md]);
195                 if (rc != 0) {
196                         CERROR("%s: LNetMDBind failed for MD %u: rc = %d\n",
197                                exp->exp_obd->obd_name, posted_md, rc);
198                         LASSERT(rc == -ENOMEM);
199                         if (posted_md == 0) {
200                                 desc->bd_md_count = 0;
201                                 RETURN(-ENOMEM);
202                         }
203                         break;
204                 }
205                 /* Network is about to get at the memory */
206                 if (desc->bd_type == BULK_PUT_SOURCE)
207                         rc = LNetPut(conn->c_self, desc->bd_mds[posted_md],
208                                      LNET_ACK_REQ, conn->c_peer,
209                                      desc->bd_portal, xid, 0, 0);
210                 else
211                         rc = LNetGet(conn->c_self, desc->bd_mds[posted_md],
212                                      conn->c_peer, desc->bd_portal, xid, 0);
213
214                 posted_md++;
215                 if (rc != 0) {
216                         CERROR("%s: failed bulk transfer with %s:%u x"LPU64": "
217                                "rc = %d\n", exp->exp_obd->obd_name,
218                                libcfs_id2str(conn->c_peer), desc->bd_portal,
219                                xid, rc);
220                         break;
221                 }
222         }
223
224         if (rc != 0) {
225                 /* Can't send, so we unlink the MD bound above.  The UNLINK
226                  * event this creates will signal completion with failure,
227                  * so we return SUCCESS here! */
228                 spin_lock(&desc->bd_lock);
229                 desc->bd_md_count -= total_md - posted_md;
230                 spin_unlock(&desc->bd_lock);
231                 LASSERT(desc->bd_md_count >= 0);
232
233                 mdunlink_iterate_helper(desc->bd_mds, posted_md);
234                 RETURN(0);
235         }
236
237         CDEBUG(D_NET, "Transferring %u pages %u bytes via portal %d "
238                "id %s xid "LPX64"-"LPX64"\n", desc->bd_iov_count,
239                desc->bd_nob, desc->bd_portal, libcfs_id2str(conn->c_peer),
240                xid - posted_md, xid - 1);
241
242         RETURN(0);
243 }
244
245 /**
246  * Server side bulk abort. Idempotent. Not thread-safe (i.e. only
247  * serialises with completion callback)
248  */
249 void ptlrpc_abort_bulk(struct ptlrpc_bulk_desc *desc)
250 {
251         struct l_wait_info       lwi;
252         int                      rc;
253
254         LASSERT(!in_interrupt());           /* might sleep */
255
256         if (!ptlrpc_server_bulk_active(desc))   /* completed or */
257                 return;                         /* never started */
258
259         /* We used to poison the pages with 0xab here because we did not want to
260          * send any meaningful data over the wire for evicted clients (bug 9297)
261          * However, this is no longer safe now that we use the page cache on the
262          * OSS (bug 20560) */
263
264         /* The unlink ensures the callback happens ASAP and is the last
265          * one.  If it fails, it must be because completion just happened,
266          * but we must still l_wait_event() in this case, to give liblustre
267          * a chance to run server_bulk_callback()*/
268         mdunlink_iterate_helper(desc->bd_mds, desc->bd_md_count);
269
270         for (;;) {
271                 /* Network access will complete in finite time but the HUGE
272                  * timeout lets us CWARN for visibility of sluggish NALs */
273                 lwi = LWI_TIMEOUT_INTERVAL(cfs_time_seconds(LONG_UNLINK),
274                                            cfs_time_seconds(1), NULL, NULL);
275                 rc = l_wait_event(desc->bd_waitq,
276                                   !ptlrpc_server_bulk_active(desc), &lwi);
277                 if (rc == 0)
278                         return;
279
280                 LASSERT(rc == -ETIMEDOUT);
281                 CWARN("Unexpectedly long timeout: desc %p\n", desc);
282         }
283 }
284 #endif /* HAVE_SERVER_SUPPORT */
285
286 /**
287  * Register bulk at the sender for later transfer.
288  * Returns 0 on success or error code.
289  */
290 int ptlrpc_register_bulk(struct ptlrpc_request *req)
291 {
292         struct ptlrpc_bulk_desc *desc = req->rq_bulk;
293         lnet_process_id_t peer;
294         int rc = 0;
295         int rc2;
296         int posted_md;
297         int total_md;
298         __u64 xid;
299         lnet_handle_me_t  me_h;
300         lnet_md_t         md;
301         ENTRY;
302
303         if (OBD_FAIL_CHECK(OBD_FAIL_PTLRPC_BULK_GET_NET))
304                 RETURN(0);
305
306         /* NB no locking required until desc is on the network */
307         LASSERT(desc->bd_nob > 0);
308         LASSERT(desc->bd_md_count == 0);
309         LASSERT(desc->bd_md_max_brw <= PTLRPC_BULK_OPS_COUNT);
310         LASSERT(desc->bd_iov_count <= PTLRPC_MAX_BRW_PAGES);
311         LASSERT(desc->bd_req != NULL);
312         LASSERT(desc->bd_type == BULK_PUT_SINK ||
313                 desc->bd_type == BULK_GET_SOURCE);
314
315         /* cleanup the state of the bulk for it will be reused */
316         if (req->rq_resend || req->rq_send_state == LUSTRE_IMP_REPLAY)
317                 desc->bd_nob_transferred = 0;
318         else
319                 LASSERT(desc->bd_nob_transferred == 0);
320
321         desc->bd_failure = 0;
322
323         peer = desc->bd_import->imp_connection->c_peer;
324
325         LASSERT(desc->bd_cbid.cbid_fn == client_bulk_callback);
326         LASSERT(desc->bd_cbid.cbid_arg == desc);
327
328         /* An XID is only used for a single request from the client.
329          * For retried bulk transfers, a new XID will be allocated in
330          * in ptlrpc_check_set() if it needs to be resent, so it is not
331          * using the same RDMA match bits after an error.
332          *
333          * For multi-bulk RPCs, rq_xid is the last XID needed for bulks. The
334          * first bulk XID is power-of-two aligned before rq_xid. LU-1431 */
335         xid = req->rq_xid & ~((__u64)desc->bd_md_max_brw - 1);
336         LASSERTF(!(desc->bd_registered &&
337                    req->rq_send_state != LUSTRE_IMP_REPLAY) ||
338                  xid != desc->bd_last_xid,
339                  "registered: %d  rq_xid: "LPU64" bd_last_xid: "LPU64"\n",
340                  desc->bd_registered, xid, desc->bd_last_xid);
341
342         total_md = (desc->bd_iov_count + LNET_MAX_IOV - 1) / LNET_MAX_IOV;
343         desc->bd_registered = 1;
344         desc->bd_last_xid = xid;
345         desc->bd_md_count = total_md;
346         md.user_ptr = &desc->bd_cbid;
347         md.eq_handle = ptlrpc_eq_h;
348         md.threshold = 1;                       /* PUT or GET */
349
350         for (posted_md = 0; posted_md < total_md; posted_md++, xid++) {
351                 md.options = PTLRPC_MD_OPTIONS |
352                              ((desc->bd_type == BULK_GET_SOURCE) ?
353                               LNET_MD_OP_GET : LNET_MD_OP_PUT);
354                 ptlrpc_fill_bulk_md(&md, desc, posted_md);
355
356                 rc = LNetMEAttach(desc->bd_portal, peer, xid, 0,
357                                   LNET_UNLINK, LNET_INS_AFTER, &me_h);
358                 if (rc != 0) {
359                         CERROR("%s: LNetMEAttach failed x"LPU64"/%d: rc = %d\n",
360                                desc->bd_import->imp_obd->obd_name, xid,
361                                posted_md, rc);
362                         break;
363                 }
364
365                 /* About to let the network at it... */
366                 rc = LNetMDAttach(me_h, md, LNET_UNLINK,
367                                   &desc->bd_mds[posted_md]);
368                 if (rc != 0) {
369                         CERROR("%s: LNetMDAttach failed x"LPU64"/%d: rc = %d\n",
370                                desc->bd_import->imp_obd->obd_name, xid,
371                                posted_md, rc);
372                         rc2 = LNetMEUnlink(me_h);
373                         LASSERT(rc2 == 0);
374                         break;
375                 }
376         }
377
378         if (rc != 0) {
379                 LASSERT(rc == -ENOMEM);
380                 spin_lock(&desc->bd_lock);
381                 desc->bd_md_count -= total_md - posted_md;
382                 spin_unlock(&desc->bd_lock);
383                 LASSERT(desc->bd_md_count >= 0);
384                 mdunlink_iterate_helper(desc->bd_mds, desc->bd_md_max_brw);
385                 req->rq_status = -ENOMEM;
386                 RETURN(-ENOMEM);
387         }
388
389         /* Set rq_xid to matchbits of the final bulk so that server can
390          * infer the number of bulks that were prepared */
391         req->rq_xid = --xid;
392         LASSERTF(desc->bd_last_xid == (req->rq_xid & PTLRPC_BULK_OPS_MASK),
393                  "bd_last_xid = x"LPU64", rq_xid = x"LPU64"\n",
394                  desc->bd_last_xid, req->rq_xid);
395
396         spin_lock(&desc->bd_lock);
397         /* Holler if peer manages to touch buffers before he knows the xid */
398         if (desc->bd_md_count != total_md)
399                 CWARN("%s: Peer %s touched %d buffers while I registered\n",
400                       desc->bd_import->imp_obd->obd_name, libcfs_id2str(peer),
401                       total_md - desc->bd_md_count);
402         spin_unlock(&desc->bd_lock);
403
404         CDEBUG(D_NET, "Setup %u bulk %s buffers: %u pages %u bytes, "
405                "xid x"LPX64"-"LPX64", portal %u\n", desc->bd_md_count,
406                desc->bd_type == BULK_GET_SOURCE ? "get-source" : "put-sink",
407                desc->bd_iov_count, desc->bd_nob,
408                desc->bd_last_xid, req->rq_xid, desc->bd_portal);
409
410         RETURN(0);
411 }
412
413 /**
414  * Disconnect a bulk desc from the network. Idempotent. Not
415  * thread-safe (i.e. only interlocks with completion callback).
416  * Returns 1 on success or 0 if network unregistration failed for whatever
417  * reason.
418  */
419 int ptlrpc_unregister_bulk(struct ptlrpc_request *req, int async)
420 {
421         struct ptlrpc_bulk_desc *desc = req->rq_bulk;
422         struct l_wait_info       lwi;
423         int                      rc;
424         ENTRY;
425
426         LASSERT(!in_interrupt());     /* might sleep */
427
428         /* Let's setup deadline for reply unlink. */
429         if (OBD_FAIL_CHECK(OBD_FAIL_PTLRPC_LONG_BULK_UNLINK) &&
430             async && req->rq_bulk_deadline == 0)
431                 req->rq_bulk_deadline = cfs_time_current_sec() + LONG_UNLINK;
432
433         if (ptlrpc_client_bulk_active(req) == 0)        /* completed or */
434                 RETURN(1);                              /* never registered */
435
436         LASSERT(desc->bd_req == req);  /* bd_req NULL until registered */
437
438         /* the unlink ensures the callback happens ASAP and is the last
439          * one.  If it fails, it must be because completion just happened,
440          * but we must still l_wait_event() in this case to give liblustre
441          * a chance to run client_bulk_callback() */
442         mdunlink_iterate_helper(desc->bd_mds, desc->bd_md_max_brw);
443
444         if (ptlrpc_client_bulk_active(req) == 0)        /* completed or */
445                 RETURN(1);                              /* never registered */
446
447         /* Move to "Unregistering" phase as bulk was not unlinked yet. */
448         ptlrpc_rqphase_move(req, RQ_PHASE_UNREGISTERING);
449
450         /* Do not wait for unlink to finish. */
451         if (async)
452                 RETURN(0);
453
454         for (;;) {
455                 /* The wq argument is ignored by user-space wait_event macros */
456                 wait_queue_head_t *wq = (req->rq_set != NULL) ?
457                                         &req->rq_set->set_waitq :
458                                         &req->rq_reply_waitq;
459                 /* Network access will complete in finite time but the HUGE
460                  * timeout lets us CWARN for visibility of sluggish NALs */
461                 lwi = LWI_TIMEOUT_INTERVAL(cfs_time_seconds(LONG_UNLINK),
462                                            cfs_time_seconds(1), NULL, NULL);
463                 rc = l_wait_event(*wq, !ptlrpc_client_bulk_active(req), &lwi);
464                 if (rc == 0) {
465                         ptlrpc_rqphase_move(req, req->rq_next_phase);
466                         RETURN(1);
467                 }
468
469                 LASSERT(rc == -ETIMEDOUT);
470                 DEBUG_REQ(D_WARNING, req, "Unexpectedly long timeout: desc %p",
471                           desc);
472         }
473         RETURN(0);
474 }
475
476 static void ptlrpc_at_set_reply(struct ptlrpc_request *req, int flags)
477 {
478         struct ptlrpc_service_part      *svcpt = req->rq_rqbd->rqbd_svcpt;
479         struct ptlrpc_service           *svc = svcpt->scp_service;
480         int service_time = max_t(int, cfs_time_current_sec() -
481                                  req->rq_arrival_time.tv_sec, 1);
482
483         if (!(flags & PTLRPC_REPLY_EARLY) &&
484             (req->rq_type != PTL_RPC_MSG_ERR) &&
485             (req->rq_reqmsg != NULL) &&
486             !(lustre_msg_get_flags(req->rq_reqmsg) &
487               (MSG_RESENT | MSG_REPLAY |
488                MSG_REQ_REPLAY_DONE | MSG_LOCK_REPLAY_DONE))) {
489                 /* early replies, errors and recovery requests don't count
490                  * toward our service time estimate */
491                 int oldse = at_measured(&svcpt->scp_at_estimate, service_time);
492
493                 if (oldse != 0) {
494                         DEBUG_REQ(D_ADAPTTO, req,
495                                   "svc %s changed estimate from %d to %d",
496                                   svc->srv_name, oldse,
497                                   at_get(&svcpt->scp_at_estimate));
498                 }
499         }
500         /* Report actual service time for client latency calc */
501         lustre_msg_set_service_time(req->rq_repmsg, service_time);
502         /* Report service time estimate for future client reqs, but report 0
503          * (to be ignored by client) if it's an error reply during recovery.
504          * (bz15815) */
505         if (req->rq_type == PTL_RPC_MSG_ERR &&
506             (req->rq_export == NULL || req->rq_export->exp_obd->obd_recovering))
507                 lustre_msg_set_timeout(req->rq_repmsg, 0);
508         else
509                 lustre_msg_set_timeout(req->rq_repmsg,
510                                        at_get(&svcpt->scp_at_estimate));
511
512         if (req->rq_reqmsg &&
513             !(lustre_msghdr_get_flags(req->rq_reqmsg) & MSGHDR_AT_SUPPORT)) {
514                 CDEBUG(D_ADAPTTO, "No early reply support: flags=%#x "
515                        "req_flags=%#x magic=%d:%x/%x len=%d\n",
516                        flags, lustre_msg_get_flags(req->rq_reqmsg),
517                        lustre_msg_is_v1(req->rq_reqmsg),
518                        lustre_msg_get_magic(req->rq_reqmsg),
519                        lustre_msg_get_magic(req->rq_repmsg), req->rq_replen);
520         }
521 }
522
523 /**
524  * Send request reply from request \a req reply buffer.
525  * \a flags defines reply types
526  * Returns 0 on success or error code
527  */
528 int ptlrpc_send_reply(struct ptlrpc_request *req, int flags)
529 {
530         struct ptlrpc_reply_state *rs = req->rq_reply_state;
531         struct ptlrpc_connection  *conn;
532         int                        rc;
533
534         /* We must already have a reply buffer (only ptlrpc_error() may be
535          * called without one). The reply generated by sptlrpc layer (e.g.
536          * error notify, etc.) might have NULL rq->reqmsg; Otherwise we must
537          * have a request buffer which is either the actual (swabbed) incoming
538          * request, or a saved copy if this is a req saved in
539          * target_queue_final_reply().
540          */
541         LASSERT (req->rq_no_reply == 0);
542         LASSERT (req->rq_reqbuf != NULL);
543         LASSERT (rs != NULL);
544         LASSERT ((flags & PTLRPC_REPLY_MAYBE_DIFFICULT) || !rs->rs_difficult);
545         LASSERT (req->rq_repmsg != NULL);
546         LASSERT (req->rq_repmsg == rs->rs_msg);
547         LASSERT (rs->rs_cb_id.cbid_fn == reply_out_callback);
548         LASSERT (rs->rs_cb_id.cbid_arg == rs);
549
550         /* There may be no rq_export during failover */
551
552         if (unlikely(req->rq_export && req->rq_export->exp_obd &&
553                      req->rq_export->exp_obd->obd_fail)) {
554                 /* Failed obd's only send ENODEV */
555                 req->rq_type = PTL_RPC_MSG_ERR;
556                 req->rq_status = -ENODEV;
557                 CDEBUG(D_HA, "sending ENODEV from failed obd %d\n",
558                        req->rq_export->exp_obd->obd_minor);
559         }
560
561         /* In order to keep interoprability with the client (< 2.3) which
562          * doesn't have pb_jobid in ptlrpc_body, We have to shrink the
563          * ptlrpc_body in reply buffer to ptlrpc_body_v2, otherwise, the
564          * reply buffer on client will be overflow.
565          *
566          * XXX Remove this whenver we drop the interoprability with such client.
567          */
568         req->rq_replen = lustre_shrink_msg(req->rq_repmsg, 0,
569                                            sizeof(struct ptlrpc_body_v2), 1);
570
571         if (req->rq_type != PTL_RPC_MSG_ERR)
572                 req->rq_type = PTL_RPC_MSG_REPLY;
573
574         lustre_msg_set_type(req->rq_repmsg, req->rq_type);
575         lustre_msg_set_status(req->rq_repmsg,
576                               ptlrpc_status_hton(req->rq_status));
577         lustre_msg_set_opc(req->rq_repmsg,
578                 req->rq_reqmsg ? lustre_msg_get_opc(req->rq_reqmsg) : 0);
579
580         target_pack_pool_reply(req);
581
582         ptlrpc_at_set_reply(req, flags);
583
584         if (req->rq_export == NULL || req->rq_export->exp_connection == NULL)
585                 conn = ptlrpc_connection_get(req->rq_peer, req->rq_self, NULL);
586         else
587                 conn = ptlrpc_connection_addref(req->rq_export->exp_connection);
588
589         if (unlikely(conn == NULL)) {
590                 CERROR("not replying on NULL connection\n"); /* bug 9635 */
591                 return -ENOTCONN;
592         }
593         ptlrpc_rs_addref(rs);                   /* +1 ref for the network */
594
595         rc = sptlrpc_svc_wrap_reply(req);
596         if (unlikely(rc))
597                 goto out;
598
599         req->rq_sent = cfs_time_current_sec();
600
601         rc = ptl_send_buf (&rs->rs_md_h, rs->rs_repbuf, rs->rs_repdata_len,
602                            (rs->rs_difficult && !rs->rs_no_ack) ?
603                            LNET_ACK_REQ : LNET_NOACK_REQ,
604                            &rs->rs_cb_id, conn,
605                            ptlrpc_req2svc(req)->srv_rep_portal,
606                            req->rq_xid, req->rq_reply_off);
607 out:
608         if (unlikely(rc != 0))
609                 ptlrpc_req_drop_rs(req);
610         ptlrpc_connection_put(conn);
611         return rc;
612 }
613
614 int ptlrpc_reply (struct ptlrpc_request *req)
615 {
616         if (req->rq_no_reply)
617                 return 0;
618         else
619                 return (ptlrpc_send_reply(req, 0));
620 }
621
622 /**
623  * For request \a req send an error reply back. Create empty
624  * reply buffers if necessary.
625  */
626 int ptlrpc_send_error(struct ptlrpc_request *req, int may_be_difficult)
627 {
628         int rc;
629         ENTRY;
630
631         if (req->rq_no_reply)
632                 RETURN(0);
633
634         if (!req->rq_repmsg) {
635                 rc = lustre_pack_reply(req, 1, NULL, NULL);
636                 if (rc)
637                         RETURN(rc);
638         }
639
640         if (req->rq_status != -ENOSPC && req->rq_status != -EACCES &&
641             req->rq_status != -EPERM && req->rq_status != -ENOENT &&
642             req->rq_status != -EINPROGRESS && req->rq_status != -EDQUOT)
643                 req->rq_type = PTL_RPC_MSG_ERR;
644
645         rc = ptlrpc_send_reply(req, may_be_difficult);
646         RETURN(rc);
647 }
648
649 int ptlrpc_error(struct ptlrpc_request *req)
650 {
651         return ptlrpc_send_error(req, 0);
652 }
653
654 /**
655  * Send request \a request.
656  * if \a noreply is set, don't expect any reply back and don't set up
657  * reply buffers.
658  * Returns 0 on success or error code.
659  */
660 int ptl_send_rpc(struct ptlrpc_request *request, int noreply)
661 {
662         int rc;
663         int rc2;
664         int mpflag = 0;
665         struct ptlrpc_connection *connection;
666         lnet_handle_me_t  reply_me_h;
667         lnet_md_t         reply_md;
668         struct obd_import *imp = request->rq_import;
669         struct obd_device *obd = imp->imp_obd;
670         ENTRY;
671
672         if (OBD_FAIL_CHECK(OBD_FAIL_PTLRPC_DROP_RPC))
673                 RETURN(0);
674
675         LASSERT(request->rq_type == PTL_RPC_MSG_REQUEST);
676         LASSERT(request->rq_wait_ctx == 0);
677
678         /* If this is a re-transmit, we're required to have disengaged
679          * cleanly from the previous attempt */
680         LASSERT(!request->rq_receiving_reply);
681         LASSERT(!((lustre_msg_get_flags(request->rq_reqmsg) & MSG_REPLAY) &&
682                 (imp->imp_state == LUSTRE_IMP_FULL)));
683
684         if (unlikely(obd != NULL && obd->obd_fail)) {
685                 CDEBUG(D_HA, "muting rpc for failed imp obd %s\n",
686                         obd->obd_name);
687                 /* this prevents us from waiting in ptlrpc_queue_wait */
688                 spin_lock(&request->rq_lock);
689                 request->rq_err = 1;
690                 spin_unlock(&request->rq_lock);
691                 request->rq_status = -ENODEV;
692                 RETURN(-ENODEV);
693         }
694
695         connection = imp->imp_connection;
696
697         lustre_msg_set_handle(request->rq_reqmsg,
698                               &imp->imp_remote_handle);
699         lustre_msg_set_type(request->rq_reqmsg, PTL_RPC_MSG_REQUEST);
700         lustre_msg_set_conn_cnt(request->rq_reqmsg,
701                                 imp->imp_conn_cnt);
702         lustre_msghdr_set_flags(request->rq_reqmsg,
703                                 imp->imp_msghdr_flags);
704
705         /** For enabled AT all request should have AT_SUPPORT in the
706          * FULL import state when OBD_CONNECT_AT is set */
707         LASSERT(AT_OFF || imp->imp_state != LUSTRE_IMP_FULL ||
708                 (imp->imp_msghdr_flags & MSGHDR_AT_SUPPORT) ||
709                 !(imp->imp_connect_data.ocd_connect_flags &
710                 OBD_CONNECT_AT));
711
712         if (request->rq_resend) {
713                 lustre_msg_add_flags(request->rq_reqmsg, MSG_RESENT);
714                 if (request->rq_resend_cb != NULL)
715                         request->rq_resend_cb(request, &request->rq_async_args);
716         }
717         if (request->rq_memalloc)
718                 mpflag = cfs_memory_pressure_get_and_set();
719
720         rc = sptlrpc_cli_wrap_request(request);
721         if (rc)
722                 GOTO(out, rc);
723
724         /* bulk register should be done after wrap_request() */
725         if (request->rq_bulk != NULL) {
726                 rc = ptlrpc_register_bulk (request);
727                 if (rc != 0)
728                         GOTO(out, rc);
729         }
730
731         if (!noreply) {
732                 LASSERT (request->rq_replen != 0);
733                 if (request->rq_repbuf == NULL) {
734                         LASSERT(request->rq_repdata == NULL);
735                         LASSERT(request->rq_repmsg == NULL);
736                         rc = sptlrpc_cli_alloc_repbuf(request,
737                                                       request->rq_replen);
738                         if (rc) {
739                                 /* this prevents us from looping in
740                                  * ptlrpc_queue_wait */
741                                 spin_lock(&request->rq_lock);
742                                 request->rq_err = 1;
743                                 spin_unlock(&request->rq_lock);
744                                 request->rq_status = rc;
745                                 GOTO(cleanup_bulk, rc);
746                         }
747                 } else {
748                         request->rq_repdata = NULL;
749                         request->rq_repmsg = NULL;
750                 }
751
752                 rc = LNetMEAttach(request->rq_reply_portal,/*XXX FIXME bug 249*/
753                                   connection->c_peer, request->rq_xid, 0,
754                                   LNET_UNLINK, LNET_INS_AFTER, &reply_me_h);
755                 if (rc != 0) {
756                         CERROR("LNetMEAttach failed: %d\n", rc);
757                         LASSERT (rc == -ENOMEM);
758                         GOTO(cleanup_bulk, rc = -ENOMEM);
759                 }
760         }
761
762         spin_lock(&request->rq_lock);
763         /* We are responsible for unlinking the reply buffer */
764         request->rq_reply_unlinked = noreply;
765         request->rq_receiving_reply = !noreply;
766         /* Clear any flags that may be present from previous sends. */
767         request->rq_req_unlinked = 0;
768         request->rq_replied = 0;
769         request->rq_err = 0;
770         request->rq_timedout = 0;
771         request->rq_net_err = 0;
772         request->rq_resend = 0;
773         request->rq_restart = 0;
774         request->rq_reply_truncated = 0;
775         spin_unlock(&request->rq_lock);
776
777         if (!noreply) {
778                 reply_md.start     = request->rq_repbuf;
779                 reply_md.length    = request->rq_repbuf_len;
780                 /* Allow multiple early replies */
781                 reply_md.threshold = LNET_MD_THRESH_INF;
782                 /* Manage remote for early replies */
783                 reply_md.options   = PTLRPC_MD_OPTIONS | LNET_MD_OP_PUT |
784                         LNET_MD_MANAGE_REMOTE |
785                         LNET_MD_TRUNCATE; /* allow to make EOVERFLOW error */;
786                 reply_md.user_ptr  = &request->rq_reply_cbid;
787                 reply_md.eq_handle = ptlrpc_eq_h;
788
789                 /* We must see the unlink callback to set rq_reply_unlinked,
790                  * so we can't auto-unlink */
791                 rc = LNetMDAttach(reply_me_h, reply_md, LNET_RETAIN,
792                                   &request->rq_reply_md_h);
793                 if (rc != 0) {
794                         CERROR("LNetMDAttach failed: %d\n", rc);
795                         LASSERT (rc == -ENOMEM);
796                         spin_lock(&request->rq_lock);
797                         /* ...but the MD attach didn't succeed... */
798                         request->rq_receiving_reply = 0;
799                         spin_unlock(&request->rq_lock);
800                         GOTO(cleanup_me, rc = -ENOMEM);
801                 }
802
803                 CDEBUG(D_NET, "Setup reply buffer: %u bytes, xid "LPU64
804                        ", portal %u\n",
805                        request->rq_repbuf_len, request->rq_xid,
806                        request->rq_reply_portal);
807         }
808
809         /* add references on request for request_out_callback */
810         ptlrpc_request_addref(request);
811         if (obd != NULL && obd->obd_svc_stats != NULL)
812                 lprocfs_counter_add(obd->obd_svc_stats, PTLRPC_REQACTIVE_CNTR,
813                         atomic_read(&imp->imp_inflight));
814
815         OBD_FAIL_TIMEOUT(OBD_FAIL_PTLRPC_DELAY_SEND, request->rq_timeout + 5);
816
817         do_gettimeofday(&request->rq_sent_tv);
818         request->rq_sent = cfs_time_current_sec();
819         /* We give the server rq_timeout secs to process the req, and
820            add the network latency for our local timeout. */
821         request->rq_deadline = request->rq_sent + request->rq_timeout +
822                 ptlrpc_at_get_net_latency(request);
823
824         ptlrpc_pinger_sending_on_import(imp);
825
826         DEBUG_REQ(D_INFO, request, "send flg=%x",
827                   lustre_msg_get_flags(request->rq_reqmsg));
828         rc = ptl_send_buf(&request->rq_req_md_h,
829                           request->rq_reqbuf, request->rq_reqdata_len,
830                           LNET_NOACK_REQ, &request->rq_req_cbid,
831                           connection,
832                           request->rq_request_portal,
833                           request->rq_xid, 0);
834         if (likely(rc == 0))
835                 GOTO(out, rc);
836
837         request->rq_req_unlinked = 1;
838         ptlrpc_req_finished(request);
839         if (noreply)
840                 GOTO(out, rc);
841
842  cleanup_me:
843         /* MEUnlink is safe; the PUT didn't even get off the ground, and
844          * nobody apart from the PUT's target has the right nid+XID to
845          * access the reply buffer. */
846         rc2 = LNetMEUnlink(reply_me_h);
847         LASSERT (rc2 == 0);
848         /* UNLINKED callback called synchronously */
849         LASSERT(!request->rq_receiving_reply);
850
851  cleanup_bulk:
852         /* We do sync unlink here as there was no real transfer here so
853          * the chance to have long unlink to sluggish net is smaller here. */
854         ptlrpc_unregister_bulk(request, 0);
855  out:
856         if (request->rq_memalloc)
857                 cfs_memory_pressure_restore(mpflag);
858         return rc;
859 }
860 EXPORT_SYMBOL(ptl_send_rpc);
861
862 /**
863  * Register request buffer descriptor for request receiving.
864  */
865 int ptlrpc_register_rqbd(struct ptlrpc_request_buffer_desc *rqbd)
866 {
867         struct ptlrpc_service     *service = rqbd->rqbd_svcpt->scp_service;
868         static lnet_process_id_t  match_id = {LNET_NID_ANY, LNET_PID_ANY};
869         int                       rc;
870         lnet_md_t                 md;
871         lnet_handle_me_t          me_h;
872
873         CDEBUG(D_NET, "LNetMEAttach: portal %d\n",
874                service->srv_req_portal);
875
876         if (OBD_FAIL_CHECK(OBD_FAIL_PTLRPC_RQBD))
877                 return (-ENOMEM);
878
879         /* NB: CPT affinity service should use new LNet flag LNET_INS_LOCAL,
880          * which means buffer can only be attached on local CPT, and LND
881          * threads can find it by grabbing a local lock */
882         rc = LNetMEAttach(service->srv_req_portal,
883                           match_id, 0, ~0, LNET_UNLINK,
884                           rqbd->rqbd_svcpt->scp_cpt >= 0 ?
885                           LNET_INS_LOCAL : LNET_INS_AFTER, &me_h);
886         if (rc != 0) {
887                 CERROR("LNetMEAttach failed: %d\n", rc);
888                 return (-ENOMEM);
889         }
890
891         LASSERT(rqbd->rqbd_refcount == 0);
892         rqbd->rqbd_refcount = 1;
893
894         md.start     = rqbd->rqbd_buffer;
895         md.length    = service->srv_buf_size;
896         md.max_size  = service->srv_max_req_size;
897         md.threshold = LNET_MD_THRESH_INF;
898         md.options   = PTLRPC_MD_OPTIONS | LNET_MD_OP_PUT | LNET_MD_MAX_SIZE;
899         md.user_ptr  = &rqbd->rqbd_cbid;
900         md.eq_handle = ptlrpc_eq_h;
901
902         rc = LNetMDAttach(me_h, md, LNET_UNLINK, &rqbd->rqbd_md_h);
903         if (rc == 0)
904                 return (0);
905
906         CERROR("LNetMDAttach failed: %d; \n", rc);
907         LASSERT (rc == -ENOMEM);
908         rc = LNetMEUnlink (me_h);
909         LASSERT (rc == 0);
910         rqbd->rqbd_refcount = 0;
911
912         return (-ENOMEM);
913 }