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[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, 2013, 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 #ifndef __KERNEL__
39 #include <liblustre.h>
40 #endif
41 #include <obd_support.h>
42 #include <lustre_net.h>
43 #include <lustre_lib.h>
44 #include <obd.h>
45 #include <obd_class.h>
46 #include "ptlrpc_internal.h"
47
48 /**
49  * Helper function. Sends \a len bytes from \a base at offset \a offset
50  * over \a conn connection to portal \a portal.
51  * Returns 0 on success or error code.
52  */
53 static int ptl_send_buf (lnet_handle_md_t *mdh, void *base, int len,
54                          lnet_ack_req_t ack, struct ptlrpc_cb_id *cbid,
55                          struct ptlrpc_connection *conn, int portal, __u64 xid,
56                          unsigned int offset)
57 {
58         int              rc;
59         lnet_md_t         md;
60         ENTRY;
61
62         LASSERT (portal != 0);
63         LASSERT (conn != NULL);
64         CDEBUG (D_INFO, "conn=%p id %s\n", conn, libcfs_id2str(conn->c_peer));
65         md.start     = base;
66         md.length    = len;
67         md.threshold = (ack == LNET_ACK_REQ) ? 2 : 1;
68         md.options   = PTLRPC_MD_OPTIONS;
69         md.user_ptr  = cbid;
70         md.eq_handle = ptlrpc_eq_h;
71
72         if (unlikely(ack == LNET_ACK_REQ &&
73                      OBD_FAIL_CHECK_ORSET(OBD_FAIL_PTLRPC_ACK, OBD_FAIL_ONCE))){
74                 /* don't ask for the ack to simulate failing client */
75                 ack = LNET_NOACK_REQ;
76         }
77
78         rc = LNetMDBind (md, LNET_UNLINK, mdh);
79         if (unlikely(rc != 0)) {
80                 CERROR ("LNetMDBind failed: %d\n", rc);
81                 LASSERT (rc == -ENOMEM);
82                 RETURN (-ENOMEM);
83         }
84
85         CDEBUG(D_NET, "Sending %d bytes to portal %d, xid "LPD64", offset %u\n",
86                len, portal, xid, offset);
87
88         rc = LNetPut (conn->c_self, *mdh, ack,
89                       conn->c_peer, portal, xid, offset, 0);
90         if (unlikely(rc != 0)) {
91                 int rc2;
92                 /* We're going to get an UNLINK event when I unlink below,
93                  * which will complete just like any other failed send, so
94                  * I fall through and return success here! */
95                 CERROR("LNetPut(%s, %d, "LPD64") failed: %d\n",
96                        libcfs_id2str(conn->c_peer), portal, xid, rc);
97                 rc2 = LNetMDUnlink(*mdh);
98                 LASSERTF(rc2 == 0, "rc2 = %d\n", rc2);
99         }
100
101         RETURN (0);
102 }
103
104 static void mdunlink_iterate_helper(lnet_handle_md_t *bd_mds, int count)
105 {
106         int i;
107
108         for (i = 0; i < count; i++)
109                 LNetMDUnlink(bd_mds[i]);
110 }
111
112 #ifdef HAVE_SERVER_SUPPORT
113 /**
114  * Prepare bulk descriptor for specified incoming request \a req that
115  * can fit \a npages * pages. \a type is bulk type. \a portal is where
116  * the bulk to be sent. Used on server-side after request was already
117  * received.
118  * Returns pointer to newly allocatrd initialized bulk descriptor or NULL on
119  * error.
120  */
121 struct ptlrpc_bulk_desc *ptlrpc_prep_bulk_exp(struct ptlrpc_request *req,
122                                               unsigned npages, unsigned max_brw,
123                                               unsigned type, unsigned portal)
124 {
125         struct obd_export *exp = req->rq_export;
126         struct ptlrpc_bulk_desc *desc;
127
128         ENTRY;
129         LASSERT(type == BULK_PUT_SOURCE || type == BULK_GET_SINK);
130
131         desc = ptlrpc_new_bulk(npages, max_brw, type, portal);
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(desc->bd_type == BULK_PUT_SOURCE ||
169                 desc->bd_type == BULK_GET_SINK);
170
171         LASSERT(desc->bd_cbid.cbid_fn == server_bulk_callback);
172         LASSERT(desc->bd_cbid.cbid_arg == desc);
173
174         /* NB total length may be 0 for a read past EOF, so we send 0
175          * length bulks, since the client expects bulk events.
176          *
177          * The client may not need all of the bulk XIDs for the RPC.  The RPC
178          * used the XID of the highest bulk XID needed, and the server masks
179          * off high bits to get bulk count for this RPC. LU-1431 */
180         xid = desc->bd_req->rq_xid & ~((__u64)desc->bd_md_max_brw - 1);
181         total_md = desc->bd_req->rq_xid - xid + 1;
182
183         desc->bd_md_count = total_md;
184         desc->bd_failure = 0;
185
186         md.user_ptr = &desc->bd_cbid;
187         md.eq_handle = ptlrpc_eq_h;
188         md.threshold = 2; /* SENT and ACK/REPLY */
189
190         for (posted_md = 0; posted_md < total_md; xid++) {
191                 md.options = PTLRPC_MD_OPTIONS;
192
193                 /* NB it's assumed that source and sink buffer frags are
194                  * page-aligned. Otherwise we'd have to send client bulk
195                  * sizes over and split server buffer accordingly */
196                 ptlrpc_fill_bulk_md(&md, desc, posted_md);
197                 rc = LNetMDBind(md, LNET_UNLINK, &desc->bd_mds[posted_md]);
198                 if (rc != 0) {
199                         CERROR("%s: LNetMDBind failed for MD %u: rc = %d\n",
200                                exp->exp_obd->obd_name, posted_md, rc);
201                         LASSERT(rc == -ENOMEM);
202                         if (posted_md == 0) {
203                                 desc->bd_md_count = 0;
204                                 RETURN(-ENOMEM);
205                         }
206                         break;
207                 }
208                 /* Network is about to get at the memory */
209                 if (desc->bd_type == BULK_PUT_SOURCE)
210                         rc = LNetPut(conn->c_self, desc->bd_mds[posted_md],
211                                      LNET_ACK_REQ, conn->c_peer,
212                                      desc->bd_portal, xid, 0, 0);
213                 else
214                         rc = LNetGet(conn->c_self, desc->bd_mds[posted_md],
215                                      conn->c_peer, desc->bd_portal, xid, 0);
216
217                 posted_md++;
218                 if (rc != 0) {
219                         CERROR("%s: failed bulk transfer with %s:%u x"LPU64": "
220                                "rc = %d\n", exp->exp_obd->obd_name,
221                                libcfs_id2str(conn->c_peer), desc->bd_portal,
222                                xid, rc);
223                         break;
224                 }
225         }
226
227         if (rc != 0) {
228                 /* Can't send, so we unlink the MD bound above.  The UNLINK
229                  * event this creates will signal completion with failure,
230                  * so we return SUCCESS here! */
231                 spin_lock(&desc->bd_lock);
232                 desc->bd_md_count -= total_md - posted_md;
233                 spin_unlock(&desc->bd_lock);
234                 LASSERT(desc->bd_md_count >= 0);
235
236                 mdunlink_iterate_helper(desc->bd_mds, posted_md);
237                 RETURN(0);
238         }
239
240         CDEBUG(D_NET, "Transferring %u pages %u bytes via portal %d "
241                "id %s xid "LPX64"-"LPX64"\n", desc->bd_iov_count,
242                desc->bd_nob, desc->bd_portal, libcfs_id2str(conn->c_peer),
243                xid - posted_md, xid - 1);
244
245         RETURN(0);
246 }
247 EXPORT_SYMBOL(ptlrpc_start_bulk_transfer);
248
249 /**
250  * Server side bulk abort. Idempotent. Not thread-safe (i.e. only
251  * serialises with completion callback)
252  */
253 void ptlrpc_abort_bulk(struct ptlrpc_bulk_desc *desc)
254 {
255         struct l_wait_info       lwi;
256         int                      rc;
257
258         LASSERT(!in_interrupt());           /* might sleep */
259
260         if (!ptlrpc_server_bulk_active(desc))   /* completed or */
261                 return;                         /* never started */
262
263         /* We used to poison the pages with 0xab here because we did not want to
264          * send any meaningful data over the wire for evicted clients (bug 9297)
265          * However, this is no longer safe now that we use the page cache on the
266          * OSS (bug 20560) */
267
268         /* The unlink ensures the callback happens ASAP and is the last
269          * one.  If it fails, it must be because completion just happened,
270          * but we must still l_wait_event() in this case, to give liblustre
271          * a chance to run server_bulk_callback()*/
272         mdunlink_iterate_helper(desc->bd_mds, desc->bd_md_count);
273
274         for (;;) {
275                 /* Network access will complete in finite time but the HUGE
276                  * timeout lets us CWARN for visibility of sluggish NALs */
277                 lwi = LWI_TIMEOUT_INTERVAL(cfs_time_seconds(LONG_UNLINK),
278                                            cfs_time_seconds(1), NULL, NULL);
279                 rc = l_wait_event(desc->bd_waitq,
280                                   !ptlrpc_server_bulk_active(desc), &lwi);
281                 if (rc == 0)
282                         return;
283
284                 LASSERT(rc == -ETIMEDOUT);
285                 CWARN("Unexpectedly long timeout: desc %p\n", desc);
286         }
287 }
288 EXPORT_SYMBOL(ptlrpc_abort_bulk);
289 #endif /* HAVE_SERVER_SUPPORT */
290
291 /**
292  * Register bulk at the sender for later transfer.
293  * Returns 0 on success or error code.
294  */
295 int ptlrpc_register_bulk(struct ptlrpc_request *req)
296 {
297         struct ptlrpc_bulk_desc *desc = req->rq_bulk;
298         lnet_process_id_t peer;
299         int rc = 0;
300         int rc2;
301         int posted_md;
302         int total_md;
303         __u64 xid;
304         lnet_handle_me_t  me_h;
305         lnet_md_t         md;
306         ENTRY;
307
308         if (OBD_FAIL_CHECK(OBD_FAIL_PTLRPC_BULK_GET_NET))
309                 RETURN(0);
310
311         /* NB no locking required until desc is on the network */
312         LASSERT(desc->bd_nob > 0);
313         LASSERT(desc->bd_md_count == 0);
314         LASSERT(desc->bd_md_max_brw <= PTLRPC_BULK_OPS_COUNT);
315         LASSERT(desc->bd_iov_count <= PTLRPC_MAX_BRW_PAGES);
316         LASSERT(desc->bd_req != NULL);
317         LASSERT(desc->bd_type == BULK_PUT_SINK ||
318                 desc->bd_type == BULK_GET_SOURCE);
319
320         /* cleanup the state of the bulk for it will be reused */
321         if (req->rq_resend || req->rq_send_state == LUSTRE_IMP_REPLAY)
322                 desc->bd_nob_transferred = 0;
323         else
324                 LASSERT(desc->bd_nob_transferred == 0);
325
326         desc->bd_failure = 0;
327
328         peer = desc->bd_import->imp_connection->c_peer;
329
330         LASSERT(desc->bd_cbid.cbid_fn == client_bulk_callback);
331         LASSERT(desc->bd_cbid.cbid_arg == desc);
332
333         /* An XID is only used for a single request from the client.
334          * For retried bulk transfers, a new XID will be allocated in
335          * in ptlrpc_check_set() if it needs to be resent, so it is not
336          * using the same RDMA match bits after an error.
337          *
338          * For multi-bulk RPCs, rq_xid is the last XID needed for bulks. The
339          * first bulk XID is power-of-two aligned before rq_xid. LU-1431 */
340         xid = req->rq_xid & ~((__u64)desc->bd_md_max_brw - 1);
341         LASSERTF(!(desc->bd_registered &&
342                    req->rq_send_state != LUSTRE_IMP_REPLAY) ||
343                  xid != desc->bd_last_xid,
344                  "registered: %d  rq_xid: "LPU64" bd_last_xid: "LPU64"\n",
345                  desc->bd_registered, xid, desc->bd_last_xid);
346
347         total_md = (desc->bd_iov_count + LNET_MAX_IOV - 1) / LNET_MAX_IOV;
348         desc->bd_registered = 1;
349         desc->bd_last_xid = xid;
350         desc->bd_md_count = total_md;
351         md.user_ptr = &desc->bd_cbid;
352         md.eq_handle = ptlrpc_eq_h;
353         md.threshold = 1;                       /* PUT or GET */
354
355         for (posted_md = 0; posted_md < total_md; posted_md++, xid++) {
356                 md.options = PTLRPC_MD_OPTIONS |
357                              ((desc->bd_type == BULK_GET_SOURCE) ?
358                               LNET_MD_OP_GET : LNET_MD_OP_PUT);
359                 ptlrpc_fill_bulk_md(&md, desc, posted_md);
360
361                 rc = LNetMEAttach(desc->bd_portal, peer, xid, 0,
362                                   LNET_UNLINK, LNET_INS_AFTER, &me_h);
363                 if (rc != 0) {
364                         CERROR("%s: LNetMEAttach failed x"LPU64"/%d: rc = %d\n",
365                                desc->bd_import->imp_obd->obd_name, xid,
366                                posted_md, rc);
367                         break;
368                 }
369
370                 /* About to let the network at it... */
371                 rc = LNetMDAttach(me_h, md, LNET_UNLINK,
372                                   &desc->bd_mds[posted_md]);
373                 if (rc != 0) {
374                         CERROR("%s: LNetMDAttach failed x"LPU64"/%d: rc = %d\n",
375                                desc->bd_import->imp_obd->obd_name, xid,
376                                posted_md, rc);
377                         rc2 = LNetMEUnlink(me_h);
378                         LASSERT(rc2 == 0);
379                         break;
380                 }
381         }
382
383         if (rc != 0) {
384                 LASSERT(rc == -ENOMEM);
385                 spin_lock(&desc->bd_lock);
386                 desc->bd_md_count -= total_md - posted_md;
387                 spin_unlock(&desc->bd_lock);
388                 LASSERT(desc->bd_md_count >= 0);
389                 mdunlink_iterate_helper(desc->bd_mds, desc->bd_md_max_brw);
390                 req->rq_status = -ENOMEM;
391                 RETURN(-ENOMEM);
392         }
393
394         /* Set rq_xid to matchbits of the final bulk so that server can
395          * infer the number of bulks that were prepared */
396         req->rq_xid = --xid;
397         LASSERTF(desc->bd_last_xid == (req->rq_xid & PTLRPC_BULK_OPS_MASK),
398                  "bd_last_xid = x"LPU64", rq_xid = x"LPU64"\n",
399                  desc->bd_last_xid, req->rq_xid);
400
401         spin_lock(&desc->bd_lock);
402         /* Holler if peer manages to touch buffers before he knows the xid */
403         if (desc->bd_md_count != total_md)
404                 CWARN("%s: Peer %s touched %d buffers while I registered\n",
405                       desc->bd_import->imp_obd->obd_name, libcfs_id2str(peer),
406                       total_md - desc->bd_md_count);
407         spin_unlock(&desc->bd_lock);
408
409         CDEBUG(D_NET, "Setup %u bulk %s buffers: %u pages %u bytes, "
410                "xid x"LPX64"-"LPX64", portal %u\n", desc->bd_md_count,
411                desc->bd_type == BULK_GET_SOURCE ? "get-source" : "put-sink",
412                desc->bd_iov_count, desc->bd_nob,
413                desc->bd_last_xid, req->rq_xid, desc->bd_portal);
414
415         RETURN(0);
416 }
417 EXPORT_SYMBOL(ptlrpc_register_bulk);
418
419 /**
420  * Disconnect a bulk desc from the network. Idempotent. Not
421  * thread-safe (i.e. only interlocks with completion callback).
422  * Returns 1 on success or 0 if network unregistration failed for whatever
423  * reason.
424  */
425 int ptlrpc_unregister_bulk(struct ptlrpc_request *req, int async)
426 {
427         struct ptlrpc_bulk_desc *desc = req->rq_bulk;
428         struct l_wait_info       lwi;
429         int                      rc;
430         ENTRY;
431
432         LASSERT(!in_interrupt());     /* might sleep */
433
434         /* Let's setup deadline for reply unlink. */
435         if (OBD_FAIL_CHECK(OBD_FAIL_PTLRPC_LONG_BULK_UNLINK) &&
436             async && req->rq_bulk_deadline == 0)
437                 req->rq_bulk_deadline = cfs_time_current_sec() + LONG_UNLINK;
438
439         if (ptlrpc_client_bulk_active(req) == 0)        /* completed or */
440                 RETURN(1);                              /* never registered */
441
442         LASSERT(desc->bd_req == req);  /* bd_req NULL until registered */
443
444         /* the unlink ensures the callback happens ASAP and is the last
445          * one.  If it fails, it must be because completion just happened,
446          * but we must still l_wait_event() in this case to give liblustre
447          * a chance to run client_bulk_callback() */
448         mdunlink_iterate_helper(desc->bd_mds, desc->bd_md_max_brw);
449
450         if (ptlrpc_client_bulk_active(req) == 0)        /* completed or */
451                 RETURN(1);                              /* never registered */
452
453         /* Move to "Unregistering" phase as bulk was not unlinked yet. */
454         ptlrpc_rqphase_move(req, RQ_PHASE_UNREGISTERING);
455
456         /* Do not wait for unlink to finish. */
457         if (async)
458                 RETURN(0);
459
460         for (;;) {
461 #ifdef __KERNEL__
462                 /* The wq argument is ignored by user-space wait_event macros */
463                 wait_queue_head_t *wq = (req->rq_set != NULL) ?
464                                         &req->rq_set->set_waitq :
465                                         &req->rq_reply_waitq;
466 #endif
467                 /* Network access will complete in finite time but the HUGE
468                  * timeout lets us CWARN for visibility of sluggish NALs */
469                 lwi = LWI_TIMEOUT_INTERVAL(cfs_time_seconds(LONG_UNLINK),
470                                            cfs_time_seconds(1), NULL, NULL);
471                 rc = l_wait_event(*wq, !ptlrpc_client_bulk_active(req), &lwi);
472                 if (rc == 0) {
473                         ptlrpc_rqphase_move(req, req->rq_next_phase);
474                         RETURN(1);
475                 }
476
477                 LASSERT(rc == -ETIMEDOUT);
478                 DEBUG_REQ(D_WARNING, req, "Unexpectedly long timeout: desc %p",
479                           desc);
480         }
481         RETURN(0);
482 }
483 EXPORT_SYMBOL(ptlrpc_unregister_bulk);
484
485 static void ptlrpc_at_set_reply(struct ptlrpc_request *req, int flags)
486 {
487         struct ptlrpc_service_part      *svcpt = req->rq_rqbd->rqbd_svcpt;
488         struct ptlrpc_service           *svc = svcpt->scp_service;
489         int service_time = max_t(int, cfs_time_current_sec() -
490                                  req->rq_arrival_time.tv_sec, 1);
491
492         if (!(flags & PTLRPC_REPLY_EARLY) &&
493             (req->rq_type != PTL_RPC_MSG_ERR) &&
494             (req->rq_reqmsg != NULL) &&
495             !(lustre_msg_get_flags(req->rq_reqmsg) &
496               (MSG_RESENT | MSG_REPLAY |
497                MSG_REQ_REPLAY_DONE | MSG_LOCK_REPLAY_DONE))) {
498                 /* early replies, errors and recovery requests don't count
499                  * toward our service time estimate */
500                 int oldse = at_measured(&svcpt->scp_at_estimate, service_time);
501
502                 if (oldse != 0) {
503                         DEBUG_REQ(D_ADAPTTO, req,
504                                   "svc %s changed estimate from %d to %d",
505                                   svc->srv_name, oldse,
506                                   at_get(&svcpt->scp_at_estimate));
507                 }
508         }
509         /* Report actual service time for client latency calc */
510         lustre_msg_set_service_time(req->rq_repmsg, service_time);
511         /* Report service time estimate for future client reqs, but report 0
512          * (to be ignored by client) if it's a error reply during recovery.
513          * (bz15815) */
514         if (req->rq_type == PTL_RPC_MSG_ERR &&
515             (req->rq_export == NULL || req->rq_export->exp_obd->obd_recovering))
516                 lustre_msg_set_timeout(req->rq_repmsg, 0);
517         else
518                 lustre_msg_set_timeout(req->rq_repmsg,
519                                        at_get(&svcpt->scp_at_estimate));
520
521         if (req->rq_reqmsg &&
522             !(lustre_msghdr_get_flags(req->rq_reqmsg) & MSGHDR_AT_SUPPORT)) {
523                 CDEBUG(D_ADAPTTO, "No early reply support: flags=%#x "
524                        "req_flags=%#x magic=%d:%x/%x len=%d\n",
525                        flags, lustre_msg_get_flags(req->rq_reqmsg),
526                        lustre_msg_is_v1(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 sucess 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 EXPORT_SYMBOL(ptlrpc_send_reply);
623
624 int ptlrpc_reply (struct ptlrpc_request *req)
625 {
626         if (req->rq_no_reply)
627                 return 0;
628         else
629                 return (ptlrpc_send_reply(req, 0));
630 }
631 EXPORT_SYMBOL(ptlrpc_reply);
632
633 /**
634  * For request \a req send an error reply back. Create empty
635  * reply buffers if necessary.
636  */
637 int ptlrpc_send_error(struct ptlrpc_request *req, int may_be_difficult)
638 {
639         int rc;
640         ENTRY;
641
642         if (req->rq_no_reply)
643                 RETURN(0);
644
645         if (!req->rq_repmsg) {
646                 rc = lustre_pack_reply(req, 1, NULL, NULL);
647                 if (rc)
648                         RETURN(rc);
649         }
650
651         if (req->rq_status != -ENOSPC && req->rq_status != -EACCES &&
652             req->rq_status != -EPERM && req->rq_status != -ENOENT &&
653             req->rq_status != -EINPROGRESS && req->rq_status != -EDQUOT)
654                 req->rq_type = PTL_RPC_MSG_ERR;
655
656         rc = ptlrpc_send_reply(req, may_be_difficult);
657         RETURN(rc);
658 }
659 EXPORT_SYMBOL(ptlrpc_send_error);
660
661 int ptlrpc_error(struct ptlrpc_request *req)
662 {
663         return ptlrpc_send_error(req, 0);
664 }
665 EXPORT_SYMBOL(ptlrpc_error);
666
667 /**
668  * Send request \a request.
669  * if \a noreply is set, don't expect any reply back and don't set up
670  * reply buffers.
671  * Returns 0 on success or error code.
672  */
673 int ptl_send_rpc(struct ptlrpc_request *request, int noreply)
674 {
675         int rc;
676         int rc2;
677         int mpflag = 0;
678         struct ptlrpc_connection *connection;
679         lnet_handle_me_t  reply_me_h;
680         lnet_md_t         reply_md;
681         struct obd_device *obd = request->rq_import->imp_obd;
682         ENTRY;
683
684         if (OBD_FAIL_CHECK(OBD_FAIL_PTLRPC_DROP_RPC))
685                 RETURN(0);
686
687         LASSERT(request->rq_type == PTL_RPC_MSG_REQUEST);
688         LASSERT(request->rq_wait_ctx == 0);
689
690         /* If this is a re-transmit, we're required to have disengaged
691          * cleanly from the previous attempt */
692         LASSERT(!request->rq_receiving_reply);
693
694         if (request->rq_import->imp_obd &&
695             request->rq_import->imp_obd->obd_fail) {
696                 CDEBUG(D_HA, "muting rpc for failed imp obd %s\n",
697                        request->rq_import->imp_obd->obd_name);
698                 /* this prevents us from waiting in ptlrpc_queue_wait */
699                 spin_lock(&request->rq_lock);
700                 request->rq_err = 1;
701                 spin_unlock(&request->rq_lock);
702                 request->rq_status = -ENODEV;
703                 RETURN(-ENODEV);
704         }
705
706         connection = request->rq_import->imp_connection;
707
708         lustre_msg_set_handle(request->rq_reqmsg,
709                               &request->rq_import->imp_remote_handle);
710         lustre_msg_set_type(request->rq_reqmsg, PTL_RPC_MSG_REQUEST);
711         lustre_msg_set_conn_cnt(request->rq_reqmsg,
712                                 request->rq_import->imp_conn_cnt);
713         lustre_msghdr_set_flags(request->rq_reqmsg,
714                                 request->rq_import->imp_msghdr_flags);
715
716         if (request->rq_resend)
717                 lustre_msg_add_flags(request->rq_reqmsg, MSG_RESENT);
718
719         if (request->rq_memalloc)
720                 mpflag = cfs_memory_pressure_get_and_set();
721
722         rc = sptlrpc_cli_wrap_request(request);
723         if (rc)
724                 GOTO(out, rc);
725
726         /* bulk register should be done after wrap_request() */
727         if (request->rq_bulk != NULL) {
728                 rc = ptlrpc_register_bulk (request);
729                 if (rc != 0)
730                         GOTO(out, rc);
731         }
732
733         if (!noreply) {
734                 LASSERT (request->rq_replen != 0);
735                 if (request->rq_repbuf == NULL) {
736                         LASSERT(request->rq_repdata == NULL);
737                         LASSERT(request->rq_repmsg == NULL);
738                         rc = sptlrpc_cli_alloc_repbuf(request,
739                                                       request->rq_replen);
740                         if (rc) {
741                                 /* this prevents us from looping in
742                                  * ptlrpc_queue_wait */
743                                 spin_lock(&request->rq_lock);
744                                 request->rq_err = 1;
745                                 spin_unlock(&request->rq_lock);
746                                 request->rq_status = rc;
747                                 GOTO(cleanup_bulk, rc);
748                         }
749                 } else {
750                         request->rq_repdata = NULL;
751                         request->rq_repmsg = NULL;
752                 }
753
754                 rc = LNetMEAttach(request->rq_reply_portal,/*XXX FIXME bug 249*/
755                                   connection->c_peer, request->rq_xid, 0,
756                                   LNET_UNLINK, LNET_INS_AFTER, &reply_me_h);
757                 if (rc != 0) {
758                         CERROR("LNetMEAttach failed: %d\n", rc);
759                         LASSERT (rc == -ENOMEM);
760                         GOTO(cleanup_bulk, rc = -ENOMEM);
761                 }
762         }
763
764         spin_lock(&request->rq_lock);
765         /* If the MD attach succeeds, there _will_ be a reply_in callback */
766         request->rq_receiving_reply = !noreply;
767         /* We are responsible for unlinking the reply buffer */
768         request->rq_must_unlink = !noreply;
769         /* Clear any flags that may be present from previous sends. */
770         request->rq_replied = 0;
771         request->rq_err = 0;
772         request->rq_timedout = 0;
773         request->rq_net_err = 0;
774         request->rq_resend = 0;
775         request->rq_restart = 0;
776         request->rq_reply_truncate = 0;
777         spin_unlock(&request->rq_lock);
778
779         if (!noreply) {
780                 reply_md.start     = request->rq_repbuf;
781                 reply_md.length    = request->rq_repbuf_len;
782                 /* Allow multiple early replies */
783                 reply_md.threshold = LNET_MD_THRESH_INF;
784                 /* Manage remote for early replies */
785                 reply_md.options   = PTLRPC_MD_OPTIONS | LNET_MD_OP_PUT |
786                         LNET_MD_MANAGE_REMOTE |
787                         LNET_MD_TRUNCATE; /* allow to make EOVERFLOW error */;
788                 reply_md.user_ptr  = &request->rq_reply_cbid;
789                 reply_md.eq_handle = ptlrpc_eq_h;
790
791                 /* We must see the unlink callback to unset rq_must_unlink,
792                    so we can't auto-unlink */
793                 rc = LNetMDAttach(reply_me_h, reply_md, LNET_RETAIN,
794                                   &request->rq_reply_md_h);
795                 if (rc != 0) {
796                         CERROR("LNetMDAttach failed: %d\n", rc);
797                         LASSERT (rc == -ENOMEM);
798                         spin_lock(&request->rq_lock);
799                         /* ...but the MD attach didn't succeed... */
800                         request->rq_receiving_reply = 0;
801                         spin_unlock(&request->rq_lock);
802                         GOTO(cleanup_me, rc = -ENOMEM);
803                 }
804
805                 CDEBUG(D_NET, "Setup reply buffer: %u bytes, xid "LPU64
806                        ", portal %u\n",
807                        request->rq_repbuf_len, request->rq_xid,
808                        request->rq_reply_portal);
809         }
810
811         /* add references on request for request_out_callback */
812         ptlrpc_request_addref(request);
813         if (obd->obd_svc_stats != NULL)
814                 lprocfs_counter_add(obd->obd_svc_stats, PTLRPC_REQACTIVE_CNTR,
815                         cfs_atomic_read(&request->rq_import->imp_inflight));
816
817         OBD_FAIL_TIMEOUT(OBD_FAIL_PTLRPC_DELAY_SEND, request->rq_timeout + 5);
818
819         do_gettimeofday(&request->rq_arrival_time);
820         request->rq_sent = cfs_time_current_sec();
821         /* We give the server rq_timeout secs to process the req, and
822            add the network latency for our local timeout. */
823         request->rq_deadline = request->rq_sent + request->rq_timeout +
824                 ptlrpc_at_get_net_latency(request);
825
826         ptlrpc_pinger_sending_on_import(request->rq_import);
827
828         DEBUG_REQ(D_INFO, request, "send flg=%x",
829                   lustre_msg_get_flags(request->rq_reqmsg));
830         rc = ptl_send_buf(&request->rq_req_md_h,
831                           request->rq_reqbuf, request->rq_reqdata_len,
832                           LNET_NOACK_REQ, &request->rq_req_cbid,
833                           connection,
834                           request->rq_request_portal,
835                           request->rq_xid, 0);
836         if (rc == 0)
837                 GOTO(out, rc);
838
839         ptlrpc_req_finished(request);
840         if (noreply)
841                 GOTO(out, rc);
842
843  cleanup_me:
844         /* MEUnlink is safe; the PUT didn't even get off the ground, and
845          * nobody apart from the PUT's target has the right nid+XID to
846          * access the reply buffer. */
847         rc2 = LNetMEUnlink(reply_me_h);
848         LASSERT (rc2 == 0);
849         /* UNLINKED callback called synchronously */
850         LASSERT(!request->rq_receiving_reply);
851
852  cleanup_bulk:
853         /* We do sync unlink here as there was no real transfer here so
854          * the chance to have long unlink to sluggish net is smaller here. */
855         ptlrpc_unregister_bulk(request, 0);
856  out:
857         if (request->rq_memalloc)
858                 cfs_memory_pressure_restore(mpflag);
859         return rc;
860 }
861 EXPORT_SYMBOL(ptl_send_rpc);
862
863 /**
864  * Register request buffer descriptor for request receiving.
865  */
866 int ptlrpc_register_rqbd(struct ptlrpc_request_buffer_desc *rqbd)
867 {
868         struct ptlrpc_service     *service = rqbd->rqbd_svcpt->scp_service;
869         static lnet_process_id_t  match_id = {LNET_NID_ANY, LNET_PID_ANY};
870         int                       rc;
871         lnet_md_t                 md;
872         lnet_handle_me_t          me_h;
873
874         CDEBUG(D_NET, "LNetMEAttach: portal %d\n",
875                service->srv_req_portal);
876
877         if (OBD_FAIL_CHECK(OBD_FAIL_PTLRPC_RQBD))
878                 return (-ENOMEM);
879
880         /* NB: CPT affinity service should use new LNet flag LNET_INS_LOCAL,
881          * which means buffer can only be attached on local CPT, and LND
882          * threads can find it by grabbing a local lock */
883         rc = LNetMEAttach(service->srv_req_portal,
884                           match_id, 0, ~0, LNET_UNLINK,
885                           rqbd->rqbd_svcpt->scp_cpt >= 0 ?
886                           LNET_INS_LOCAL : LNET_INS_AFTER, &me_h);
887         if (rc != 0) {
888                 CERROR("LNetMEAttach failed: %d\n", rc);
889                 return (-ENOMEM);
890         }
891
892         LASSERT(rqbd->rqbd_refcount == 0);
893         rqbd->rqbd_refcount = 1;
894
895         md.start     = rqbd->rqbd_buffer;
896         md.length    = service->srv_buf_size;
897         md.max_size  = service->srv_max_req_size;
898         md.threshold = LNET_MD_THRESH_INF;
899         md.options   = PTLRPC_MD_OPTIONS | LNET_MD_OP_PUT | LNET_MD_MAX_SIZE;
900         md.user_ptr  = &rqbd->rqbd_cbid;
901         md.eq_handle = ptlrpc_eq_h;
902
903         rc = LNetMDAttach(me_h, md, LNET_UNLINK, &rqbd->rqbd_md_h);
904         if (rc == 0)
905                 return (0);
906
907         CERROR("LNetMDAttach failed: %d; \n", rc);
908         LASSERT (rc == -ENOMEM);
909         rc = LNetMEUnlink (me_h);
910         LASSERT (rc == 0);
911         rqbd->rqbd_refcount = 0;
912
913         return (-ENOMEM);
914 }