Whamcloud - gitweb
LU-12678 o2iblnd: Use list_for_each_entry_safe
[fs/lustre-release.git] / lnet / klnds / o2iblnd / o2iblnd_cb.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.gnu.org/licenses/gpl-2.0.html
19  *
20  * GPL HEADER END
21  */
22 /*
23  * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
24  * Use is subject to license terms.
25  *
26  * Copyright (c) 2012, 2017, Intel Corporation.
27  */
28 /*
29  * This file is part of Lustre, http://www.lustre.org/
30  * Lustre is a trademark of Sun Microsystems, Inc.
31  *
32  * lnet/klnds/o2iblnd/o2iblnd_cb.c
33  *
34  * Author: Eric Barton <eric@bartonsoftware.com>
35  */
36
37 #include "o2iblnd.h"
38
39 #define MAX_CONN_RACES_BEFORE_ABORT 20
40
41 static void kiblnd_peer_alive(struct kib_peer_ni *peer_ni);
42 static void kiblnd_peer_connect_failed(struct kib_peer_ni *peer_ni, int active,
43                                        int error);
44 static void kiblnd_init_tx_msg(struct lnet_ni *ni, struct kib_tx *tx,
45                                int type, int body_nob);
46 static int kiblnd_init_rdma(struct kib_conn *conn, struct kib_tx *tx, int type,
47                             int resid, struct kib_rdma_desc *dstrd, u64 dstcookie);
48 static void kiblnd_queue_tx_locked(struct kib_tx *tx, struct kib_conn *conn);
49 static void kiblnd_queue_tx(struct kib_tx *tx, struct kib_conn *conn);
50
51 static void kiblnd_unmap_tx(struct kib_tx *tx);
52 static void kiblnd_check_sends_locked(struct kib_conn *conn);
53
54 void
55 kiblnd_tx_done(struct kib_tx *tx)
56 {
57         struct lnet_msg *lntmsg[2];
58         int         rc;
59         int         i;
60
61         LASSERT (!in_interrupt());
62         LASSERT (!tx->tx_queued);               /* mustn't be queued for sending */
63         LASSERT (tx->tx_sending == 0);          /* mustn't be awaiting sent callback */
64         LASSERT (!tx->tx_waiting);              /* mustn't be awaiting peer_ni response */
65         LASSERT (tx->tx_pool != NULL);
66
67         kiblnd_unmap_tx(tx);
68
69         /* tx may have up to 2 lnet msgs to finalise */
70         lntmsg[0] = tx->tx_lntmsg[0]; tx->tx_lntmsg[0] = NULL;
71         lntmsg[1] = tx->tx_lntmsg[1]; tx->tx_lntmsg[1] = NULL;
72         rc = tx->tx_status;
73
74         if (tx->tx_conn != NULL) {
75                 kiblnd_conn_decref(tx->tx_conn);
76                 tx->tx_conn = NULL;
77         }
78
79         tx->tx_nwrq = tx->tx_nsge = 0;
80         tx->tx_status = 0;
81
82         kiblnd_pool_free_node(&tx->tx_pool->tpo_pool, &tx->tx_list);
83
84         /* delay finalize until my descs have been freed */
85         for (i = 0; i < 2; i++) {
86                 if (lntmsg[i] == NULL)
87                         continue;
88
89                 /* propagate health status to LNet for requests */
90                 if (i == 0 && lntmsg[i])
91                         lntmsg[i]->msg_health_status = tx->tx_hstatus;
92
93                 lnet_finalize(lntmsg[i], rc);
94         }
95 }
96
97 void
98 kiblnd_txlist_done(struct list_head *txlist, int status,
99                    enum lnet_msg_hstatus hstatus)
100 {
101         struct kib_tx *tx;
102
103         while (!list_empty(txlist)) {
104                 tx = list_entry(txlist->next, struct kib_tx, tx_list);
105
106                 list_del(&tx->tx_list);
107                 /* complete now */
108                 tx->tx_waiting = 0;
109                 tx->tx_status = status;
110                 if (hstatus != LNET_MSG_STATUS_OK)
111                         tx->tx_hstatus = hstatus;
112                 kiblnd_tx_done(tx);
113         }
114 }
115
116 static struct kib_tx *
117 kiblnd_get_idle_tx(struct lnet_ni *ni, lnet_nid_t target)
118 {
119         struct kib_net *net = ni->ni_data;
120         struct list_head *node;
121         struct kib_tx *tx;
122         struct kib_tx_poolset *tps;
123
124         tps = net->ibn_tx_ps[lnet_cpt_of_nid(target, ni)];
125         node = kiblnd_pool_alloc_node(&tps->tps_poolset);
126         if (node == NULL)
127                 return NULL;
128         tx = container_of(node, struct kib_tx, tx_list);
129
130         LASSERT (tx->tx_nwrq == 0);
131         LASSERT (!tx->tx_queued);
132         LASSERT (tx->tx_sending == 0);
133         LASSERT (!tx->tx_waiting);
134         LASSERT (tx->tx_status == 0);
135         LASSERT (tx->tx_conn == NULL);
136         LASSERT (tx->tx_lntmsg[0] == NULL);
137         LASSERT (tx->tx_lntmsg[1] == NULL);
138         LASSERT (tx->tx_nfrags == 0);
139
140         tx->tx_gaps = false;
141         tx->tx_hstatus = LNET_MSG_STATUS_OK;
142
143         return tx;
144 }
145
146 static void
147 kiblnd_drop_rx(struct kib_rx *rx)
148 {
149         struct kib_conn *conn = rx->rx_conn;
150         struct kib_sched_info *sched = conn->ibc_sched;
151         unsigned long flags;
152
153         spin_lock_irqsave(&sched->ibs_lock, flags);
154         LASSERT(conn->ibc_nrx > 0);
155         conn->ibc_nrx--;
156         spin_unlock_irqrestore(&sched->ibs_lock, flags);
157
158         kiblnd_conn_decref(conn);
159 }
160
161 int
162 kiblnd_post_rx(struct kib_rx *rx, int credit)
163 {
164         struct kib_conn *conn = rx->rx_conn;
165         struct kib_net *net = conn->ibc_peer->ibp_ni->ni_data;
166         struct ib_recv_wr *bad_wrq = NULL;
167 #ifdef HAVE_IB_GET_DMA_MR
168         struct ib_mr *mr = conn->ibc_hdev->ibh_mrs;
169 #endif
170         int rc;
171
172         LASSERT (net != NULL);
173         LASSERT (!in_interrupt());
174         LASSERT (credit == IBLND_POSTRX_NO_CREDIT ||
175                  credit == IBLND_POSTRX_PEER_CREDIT ||
176                  credit == IBLND_POSTRX_RSRVD_CREDIT);
177 #ifdef HAVE_IB_GET_DMA_MR
178         LASSERT(mr != NULL);
179
180         rx->rx_sge.lkey   = mr->lkey;
181 #else
182         rx->rx_sge.lkey   = conn->ibc_hdev->ibh_pd->local_dma_lkey;
183 #endif
184         rx->rx_sge.addr   = rx->rx_msgaddr;
185         rx->rx_sge.length = IBLND_MSG_SIZE;
186
187         rx->rx_wrq.next = NULL;
188         rx->rx_wrq.sg_list = &rx->rx_sge;
189         rx->rx_wrq.num_sge = 1;
190         rx->rx_wrq.wr_id = kiblnd_ptr2wreqid(rx, IBLND_WID_RX);
191
192         LASSERT (conn->ibc_state >= IBLND_CONN_INIT);
193         LASSERT (rx->rx_nob >= 0);              /* not posted */
194
195         if (conn->ibc_state > IBLND_CONN_ESTABLISHED) {
196                 kiblnd_drop_rx(rx);             /* No more posts for this rx */
197                 return 0;
198         }
199
200         rx->rx_nob = -1;                        /* flag posted */
201
202         /* NB: need an extra reference after ib_post_recv because we don't
203          * own this rx (and rx::rx_conn) anymore, LU-5678.
204          */
205         kiblnd_conn_addref(conn);
206 #ifdef HAVE_IB_POST_SEND_RECV_CONST
207         rc = ib_post_recv(conn->ibc_cmid->qp, &rx->rx_wrq,
208                           (const struct ib_recv_wr **)&bad_wrq);
209 #else
210         rc = ib_post_recv(conn->ibc_cmid->qp, &rx->rx_wrq, &bad_wrq);
211 #endif
212         if (unlikely(rc != 0)) {
213                 CERROR("Can't post rx for %s: %d, bad_wrq: %p\n",
214                        libcfs_nid2str(conn->ibc_peer->ibp_nid), rc, bad_wrq);
215                 rx->rx_nob = 0;
216         }
217
218         if (conn->ibc_state < IBLND_CONN_ESTABLISHED) /* Initial post */
219                 goto out;
220
221         if (unlikely(rc != 0)) {
222                 kiblnd_close_conn(conn, rc);
223                 kiblnd_drop_rx(rx);     /* No more posts for this rx */
224                 goto out;
225         }
226
227         if (credit == IBLND_POSTRX_NO_CREDIT)
228                 goto out;
229
230         spin_lock(&conn->ibc_lock);
231         if (credit == IBLND_POSTRX_PEER_CREDIT)
232                 conn->ibc_outstanding_credits++;
233         else
234                 conn->ibc_reserved_credits++;
235         kiblnd_check_sends_locked(conn);
236         spin_unlock(&conn->ibc_lock);
237
238 out:
239         kiblnd_conn_decref(conn);
240         return rc;
241 }
242
243 static struct kib_tx *
244 kiblnd_find_waiting_tx_locked(struct kib_conn *conn, int txtype, u64 cookie)
245 {
246         struct list_head *tmp;
247
248         list_for_each(tmp, &conn->ibc_active_txs) {
249                 struct kib_tx *tx = list_entry(tmp, struct kib_tx, tx_list);
250
251                 LASSERT(!tx->tx_queued);
252                 LASSERT(tx->tx_sending != 0 || tx->tx_waiting);
253
254                 if (tx->tx_cookie != cookie)
255                         continue;
256
257                 if (tx->tx_waiting &&
258                     tx->tx_msg->ibm_type == txtype)
259                         return tx;
260
261                 CWARN("Bad completion: %swaiting, type %x (wanted %x)\n",
262                       tx->tx_waiting ? "" : "NOT ",
263                       tx->tx_msg->ibm_type, txtype);
264         }
265         return NULL;
266 }
267
268 static void
269 kiblnd_handle_completion(struct kib_conn *conn, int txtype, int status, u64 cookie)
270 {
271         struct kib_tx *tx;
272         struct lnet_ni *ni = conn->ibc_peer->ibp_ni;
273         int idle;
274
275         spin_lock(&conn->ibc_lock);
276
277         tx = kiblnd_find_waiting_tx_locked(conn, txtype, cookie);
278         if (tx == NULL) {
279                 spin_unlock(&conn->ibc_lock);
280
281                 CWARN("Unmatched completion type %x cookie %#llx from %s\n",
282                       txtype, cookie, libcfs_nid2str(conn->ibc_peer->ibp_nid));
283                 kiblnd_close_conn(conn, -EPROTO);
284                 return;
285         }
286
287         if (tx->tx_status == 0) {               /* success so far */
288                 if (status < 0) {               /* failed? */
289                         tx->tx_status = status;
290                         tx->tx_hstatus = LNET_MSG_STATUS_REMOTE_ERROR;
291                 } else if (txtype == IBLND_MSG_GET_REQ) {
292                         lnet_set_reply_msg_len(ni, tx->tx_lntmsg[1], status);
293                 }
294         }
295
296         tx->tx_waiting = 0;
297
298         idle = !tx->tx_queued && (tx->tx_sending == 0);
299         if (idle)
300                 list_del(&tx->tx_list);
301
302         spin_unlock(&conn->ibc_lock);
303
304         if (idle)
305                 kiblnd_tx_done(tx);
306 }
307
308 static void
309 kiblnd_send_completion(struct kib_conn *conn, int type, int status, u64 cookie)
310 {
311         struct lnet_ni *ni = conn->ibc_peer->ibp_ni;
312         struct kib_tx *tx = kiblnd_get_idle_tx(ni, conn->ibc_peer->ibp_nid);
313
314         if (tx == NULL) {
315                 CERROR("Can't get tx for completion %x for %s\n",
316                        type, libcfs_nid2str(conn->ibc_peer->ibp_nid));
317                 return;
318         }
319
320         tx->tx_msg->ibm_u.completion.ibcm_status = status;
321         tx->tx_msg->ibm_u.completion.ibcm_cookie = cookie;
322         kiblnd_init_tx_msg(ni, tx, type, sizeof(struct kib_completion_msg));
323
324         kiblnd_queue_tx(tx, conn);
325 }
326
327 static void
328 kiblnd_handle_rx(struct kib_rx *rx)
329 {
330         struct kib_msg *msg = rx->rx_msg;
331         struct kib_conn   *conn = rx->rx_conn;
332         struct lnet_ni *ni = conn->ibc_peer->ibp_ni;
333         int           credits = msg->ibm_credits;
334         struct kib_tx *tx;
335         int           rc = 0;
336         int           rc2;
337         int           post_credit;
338
339         LASSERT (conn->ibc_state >= IBLND_CONN_ESTABLISHED);
340
341         CDEBUG (D_NET, "Received %x[%d] from %s\n",
342                 msg->ibm_type, credits,
343                 libcfs_nid2str(conn->ibc_peer->ibp_nid));
344
345         if (credits != 0) {
346                 /* Have I received credits that will let me send? */
347                 spin_lock(&conn->ibc_lock);
348
349                 if (conn->ibc_credits + credits >
350                     conn->ibc_queue_depth) {
351                         rc2 = conn->ibc_credits;
352                         spin_unlock(&conn->ibc_lock);
353
354                         CERROR("Bad credits from %s: %d + %d > %d\n",
355                                libcfs_nid2str(conn->ibc_peer->ibp_nid),
356                                rc2, credits,
357                                conn->ibc_queue_depth);
358
359                         kiblnd_close_conn(conn, -EPROTO);
360                         kiblnd_post_rx(rx, IBLND_POSTRX_NO_CREDIT);
361                         return;
362                 }
363
364                 conn->ibc_credits += credits;
365
366                 /* This ensures the credit taken by NOOP can be returned */
367                 if (msg->ibm_type == IBLND_MSG_NOOP &&
368                     !IBLND_OOB_CAPABLE(conn->ibc_version)) /* v1 only */
369                         conn->ibc_outstanding_credits++;
370
371                 kiblnd_check_sends_locked(conn);
372                 spin_unlock(&conn->ibc_lock);
373         }
374
375         switch (msg->ibm_type) {
376         default:
377                 CERROR("Bad IBLND message type %x from %s\n",
378                        msg->ibm_type, libcfs_nid2str(conn->ibc_peer->ibp_nid));
379                 post_credit = IBLND_POSTRX_NO_CREDIT;
380                 rc = -EPROTO;
381                 break;
382
383         case IBLND_MSG_NOOP:
384                 if (IBLND_OOB_CAPABLE(conn->ibc_version)) {
385                         post_credit = IBLND_POSTRX_NO_CREDIT;
386                         break;
387                 }
388
389                 if (credits != 0) /* credit already posted */
390                         post_credit = IBLND_POSTRX_NO_CREDIT;
391                 else              /* a keepalive NOOP */
392                         post_credit = IBLND_POSTRX_PEER_CREDIT;
393                 break;
394
395         case IBLND_MSG_IMMEDIATE:
396                 post_credit = IBLND_POSTRX_DONT_POST;
397                 rc = lnet_parse(ni, &msg->ibm_u.immediate.ibim_hdr,
398                                 msg->ibm_srcnid, rx, 0);
399                 if (rc < 0)                     /* repost on error */
400                         post_credit = IBLND_POSTRX_PEER_CREDIT;
401                 break;
402
403         case IBLND_MSG_PUT_REQ:
404                 post_credit = IBLND_POSTRX_DONT_POST;
405                 rc = lnet_parse(ni, &msg->ibm_u.putreq.ibprm_hdr,
406                                 msg->ibm_srcnid, rx, 1);
407                 if (rc < 0)                     /* repost on error */
408                         post_credit = IBLND_POSTRX_PEER_CREDIT;
409                 break;
410
411         case IBLND_MSG_PUT_NAK:
412                 CWARN ("PUT_NACK from %s\n",
413                        libcfs_nid2str(conn->ibc_peer->ibp_nid));
414                 post_credit = IBLND_POSTRX_RSRVD_CREDIT;
415                 kiblnd_handle_completion(conn, IBLND_MSG_PUT_REQ,
416                                          msg->ibm_u.completion.ibcm_status,
417                                          msg->ibm_u.completion.ibcm_cookie);
418                 break;
419
420         case IBLND_MSG_PUT_ACK:
421                 post_credit = IBLND_POSTRX_RSRVD_CREDIT;
422
423                 spin_lock(&conn->ibc_lock);
424                 tx = kiblnd_find_waiting_tx_locked(conn, IBLND_MSG_PUT_REQ,
425                                         msg->ibm_u.putack.ibpam_src_cookie);
426                 if (tx != NULL)
427                         list_del(&tx->tx_list);
428                 spin_unlock(&conn->ibc_lock);
429
430                 if (tx == NULL) {
431                         CERROR("Unmatched PUT_ACK from %s\n",
432                                libcfs_nid2str(conn->ibc_peer->ibp_nid));
433                         rc = -EPROTO;
434                         break;
435                 }
436
437                 LASSERT (tx->tx_waiting);
438                 /* CAVEAT EMPTOR: I could be racing with tx_complete, but...
439                  * (a) I can overwrite tx_msg since my peer_ni has received it!
440                  * (b) tx_waiting set tells tx_complete() it's not done. */
441
442                 tx->tx_nwrq = tx->tx_nsge = 0;  /* overwrite PUT_REQ */
443
444                 rc2 = kiblnd_init_rdma(conn, tx, IBLND_MSG_PUT_DONE,
445                                        kiblnd_rd_size(&msg->ibm_u.putack.ibpam_rd),
446                                        &msg->ibm_u.putack.ibpam_rd,
447                                        msg->ibm_u.putack.ibpam_dst_cookie);
448                 if (rc2 < 0)
449                         CERROR("Can't setup rdma for PUT to %s: %d\n",
450                                libcfs_nid2str(conn->ibc_peer->ibp_nid), rc2);
451
452                 spin_lock(&conn->ibc_lock);
453                 tx->tx_waiting = 0;     /* clear waiting and queue atomically */
454                 kiblnd_queue_tx_locked(tx, conn);
455                 spin_unlock(&conn->ibc_lock);
456                 break;
457
458         case IBLND_MSG_PUT_DONE:
459                 post_credit = IBLND_POSTRX_PEER_CREDIT;
460                 kiblnd_handle_completion(conn, IBLND_MSG_PUT_ACK,
461                                          msg->ibm_u.completion.ibcm_status,
462                                          msg->ibm_u.completion.ibcm_cookie);
463                 break;
464
465         case IBLND_MSG_GET_REQ:
466                 post_credit = IBLND_POSTRX_DONT_POST;
467                 rc = lnet_parse(ni, &msg->ibm_u.get.ibgm_hdr,
468                                 msg->ibm_srcnid, rx, 1);
469                 if (rc < 0)                     /* repost on error */
470                         post_credit = IBLND_POSTRX_PEER_CREDIT;
471                 break;
472
473         case IBLND_MSG_GET_DONE:
474                 post_credit = IBLND_POSTRX_RSRVD_CREDIT;
475                 kiblnd_handle_completion(conn, IBLND_MSG_GET_REQ,
476                                          msg->ibm_u.completion.ibcm_status,
477                                          msg->ibm_u.completion.ibcm_cookie);
478                 break;
479         }
480
481         if (rc < 0)                             /* protocol error */
482                 kiblnd_close_conn(conn, rc);
483
484         if (post_credit != IBLND_POSTRX_DONT_POST)
485                 kiblnd_post_rx(rx, post_credit);
486 }
487
488 static void
489 kiblnd_rx_complete(struct kib_rx *rx, int status, int nob)
490 {
491         struct kib_msg *msg = rx->rx_msg;
492         struct kib_conn   *conn = rx->rx_conn;
493         struct lnet_ni *ni = conn->ibc_peer->ibp_ni;
494         struct kib_net *net = ni->ni_data;
495         int rc;
496         int err = -EIO;
497
498         LASSERT (net != NULL);
499         LASSERT (rx->rx_nob < 0);               /* was posted */
500         rx->rx_nob = 0;                         /* isn't now */
501
502         if (conn->ibc_state > IBLND_CONN_ESTABLISHED)
503                 goto ignore;
504
505         if (status != IB_WC_SUCCESS) {
506                 CNETERR("Rx from %s failed: %d\n",
507                         libcfs_nid2str(conn->ibc_peer->ibp_nid), status);
508                 goto failed;
509         }
510
511         LASSERT (nob >= 0);
512         rx->rx_nob = nob;
513
514         rc = kiblnd_unpack_msg(msg, rx->rx_nob);
515         if (rc != 0) {
516                 CERROR ("Error %d unpacking rx from %s\n",
517                         rc, libcfs_nid2str(conn->ibc_peer->ibp_nid));
518                 goto failed;
519         }
520
521         if (msg->ibm_srcnid != conn->ibc_peer->ibp_nid ||
522             msg->ibm_dstnid != ni->ni_nid ||
523             msg->ibm_srcstamp != conn->ibc_incarnation ||
524             msg->ibm_dststamp != net->ibn_incarnation) {
525                 CERROR ("Stale rx from %s\n",
526                         libcfs_nid2str(conn->ibc_peer->ibp_nid));
527                 err = -ESTALE;
528                 goto failed;
529         }
530
531         /* set time last known alive */
532         kiblnd_peer_alive(conn->ibc_peer);
533
534         /* racing with connection establishment/teardown! */
535
536         if (conn->ibc_state < IBLND_CONN_ESTABLISHED) {
537                 rwlock_t  *g_lock = &kiblnd_data.kib_global_lock;
538                 unsigned long  flags;
539
540                 write_lock_irqsave(g_lock, flags);
541                 /* must check holding global lock to eliminate race */
542                 if (conn->ibc_state < IBLND_CONN_ESTABLISHED) {
543                         list_add_tail(&rx->rx_list, &conn->ibc_early_rxs);
544                         write_unlock_irqrestore(g_lock, flags);
545                         return;
546                 }
547                 write_unlock_irqrestore(g_lock, flags);
548         }
549         kiblnd_handle_rx(rx);
550         return;
551
552  failed:
553         CDEBUG(D_NET, "rx %p conn %p\n", rx, conn);
554         kiblnd_close_conn(conn, err);
555  ignore:
556         kiblnd_drop_rx(rx);                     /* Don't re-post rx. */
557 }
558
559 static int
560 kiblnd_fmr_map_tx(struct kib_net *net, struct kib_tx *tx,
561                   struct kib_rdma_desc *rd, u32 nob)
562 {
563         struct kib_hca_dev *hdev;
564         struct kib_dev *dev;
565         struct kib_fmr_poolset *fps;
566         int                     cpt;
567         int                     rc;
568         int i;
569
570         LASSERT(tx->tx_pool != NULL);
571         LASSERT(tx->tx_pool->tpo_pool.po_owner != NULL);
572
573         dev = net->ibn_dev;
574         hdev = tx->tx_pool->tpo_hdev;
575         cpt = tx->tx_pool->tpo_pool.po_owner->ps_cpt;
576
577         /*
578          * If we're dealing with FastReg, but the device doesn't
579          * support GAPS and the tx has GAPS, then there is no real point
580          * in trying to map the memory, because it'll just fail. So
581          * preemptively fail with an appropriate message
582          */
583         if ((dev->ibd_dev_caps & IBLND_DEV_CAPS_FASTREG_ENABLED) &&
584             !(dev->ibd_dev_caps & IBLND_DEV_CAPS_FASTREG_GAPS_SUPPORT) &&
585             tx->tx_gaps) {
586                 CERROR("Using FastReg with no GAPS support, but tx has gaps. "
587                        "Try setting use_fastreg_gaps to 1\n");
588                 return -EPROTONOSUPPORT;
589         }
590
591         /*
592          * FMR does not support gaps but the tx has gaps then
593          * we should make sure that the number of fragments we'll be sending
594          * over fits within the number of fragments negotiated on the
595          * connection, otherwise, we won't be able to RDMA the data.
596          * We need to maintain the number of fragments negotiation on the
597          * connection for backwards compatibility.
598          */
599         if (tx->tx_gaps && (dev->ibd_dev_caps & IBLND_DEV_CAPS_FMR_ENABLED)) {
600                 if (tx->tx_conn &&
601                     tx->tx_conn->ibc_max_frags <= rd->rd_nfrags) {
602                         CERROR("TX number of frags (%d) is <= than connection"
603                                " number of frags (%d). Consider setting peer's"
604                                " map_on_demand to 256\n", tx->tx_nfrags,
605                                tx->tx_conn->ibc_max_frags);
606                         return -EFBIG;
607                 }
608         }
609
610         fps = net->ibn_fmr_ps[cpt];
611         rc = kiblnd_fmr_pool_map(fps, tx, rd, nob, 0, &tx->tx_fmr);
612         if (rc != 0) {
613                 CERROR("Can't map %u bytes (%u/%u)s: %d\n", nob,
614                        tx->tx_nfrags, rd->rd_nfrags, rc);
615                 return rc;
616         }
617
618         /*
619          * If rd is not tx_rd, it's going to get sent to a peer_ni, who will
620          * need the rkey
621          */
622         rd->rd_key = tx->tx_fmr.fmr_key;
623         /*
624          * for FastReg or FMR with no gaps we can accumulate all
625          * the fragments in one FastReg or FMR fragment.
626          */
627         if (((dev->ibd_dev_caps & IBLND_DEV_CAPS_FMR_ENABLED) && !tx->tx_gaps) ||
628             (dev->ibd_dev_caps & IBLND_DEV_CAPS_FASTREG_ENABLED)) {
629                 /* FMR requires zero based address */
630                 if (dev->ibd_dev_caps & IBLND_DEV_CAPS_FMR_ENABLED)
631                         rd->rd_frags[0].rf_addr &= ~hdev->ibh_page_mask;
632                 rd->rd_frags[0].rf_nob = nob;
633                 rd->rd_nfrags = 1;
634         } else {
635                 /*
636                  * We're transmitting with gaps using FMR.
637                  * We'll need to use multiple fragments and identify the
638                  * zero based address of each fragment.
639                  */
640                 for (i = 0; i < rd->rd_nfrags; i++) {
641                         rd->rd_frags[i].rf_addr &= ~hdev->ibh_page_mask;
642                         rd->rd_frags[i].rf_addr += i << hdev->ibh_page_shift;
643                 }
644         }
645
646         return 0;
647 }
648
649 static void
650 kiblnd_unmap_tx(struct kib_tx *tx)
651 {
652         if (tx->tx_fmr.fmr_pfmr || tx->tx_fmr.fmr_frd)
653                 kiblnd_fmr_pool_unmap(&tx->tx_fmr, tx->tx_status);
654
655         if (tx->tx_nfrags != 0) {
656                 kiblnd_dma_unmap_sg(tx->tx_pool->tpo_hdev->ibh_ibdev,
657                                     tx->tx_frags, tx->tx_nfrags, tx->tx_dmadir);
658                 tx->tx_nfrags = 0;
659         }
660 }
661
662 #ifdef HAVE_IB_GET_DMA_MR
663 static struct ib_mr *
664 kiblnd_find_rd_dma_mr(struct lnet_ni *ni, struct kib_rdma_desc *rd)
665 {
666         struct kib_net *net = ni->ni_data;
667         struct kib_hca_dev *hdev = net->ibn_dev->ibd_hdev;
668         struct lnet_ioctl_config_o2iblnd_tunables *tunables;
669
670         tunables = &ni->ni_lnd_tunables.lnd_tun_u.lnd_o2ib;
671
672         /*
673          * if map-on-demand is turned on and the device supports
674          * either FMR or FastReg then use that. Otherwise use global
675          * memory regions. If that's not available either, then you're
676          * dead in the water and fail the operation.
677          */
678         if (tunables->lnd_map_on_demand &&
679             (net->ibn_dev->ibd_dev_caps & IBLND_DEV_CAPS_FASTREG_ENABLED ||
680              net->ibn_dev->ibd_dev_caps & IBLND_DEV_CAPS_FMR_ENABLED))
681                 return NULL;
682
683         /*
684          * hdev->ibh_mrs can be NULL. This case is dealt with gracefully
685          * in the call chain. The mapping will fail with appropriate error
686          * message.
687          */
688         return hdev->ibh_mrs;
689 }
690 #endif
691
692 static int kiblnd_map_tx(struct lnet_ni *ni, struct kib_tx *tx,
693                          struct kib_rdma_desc *rd, int nfrags)
694 {
695         struct kib_net *net = ni->ni_data;
696         struct kib_hca_dev *hdev = net->ibn_dev->ibd_hdev;
697 #ifdef HAVE_IB_GET_DMA_MR
698         struct ib_mr *mr = NULL;
699 #endif
700         __u32 nob;
701         int i;
702
703         /* If rd is not tx_rd, it's going to get sent to a peer_ni and I'm the
704          * RDMA sink */
705         tx->tx_dmadir = (rd != tx->tx_rd) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
706         tx->tx_nfrags = nfrags;
707
708         rd->rd_nfrags = kiblnd_dma_map_sg(hdev->ibh_ibdev, tx->tx_frags,
709                                           tx->tx_nfrags, tx->tx_dmadir);
710
711         for (i = 0, nob = 0; i < rd->rd_nfrags; i++) {
712                 rd->rd_frags[i].rf_nob  = kiblnd_sg_dma_len(
713                         hdev->ibh_ibdev, &tx->tx_frags[i]);
714                 rd->rd_frags[i].rf_addr = kiblnd_sg_dma_address(
715                         hdev->ibh_ibdev, &tx->tx_frags[i]);
716                 nob += rd->rd_frags[i].rf_nob;
717         }
718
719 #ifdef HAVE_IB_GET_DMA_MR
720         mr = kiblnd_find_rd_dma_mr(ni, rd);
721         if (mr != NULL) {
722                 /* found pre-mapping MR */
723                 rd->rd_key = (rd != tx->tx_rd) ? mr->rkey : mr->lkey;
724                 return 0;
725         }
726 #endif
727
728         if (net->ibn_fmr_ps != NULL)
729                 return kiblnd_fmr_map_tx(net, tx, rd, nob);
730
731         return -EINVAL;
732 }
733
734 static int kiblnd_setup_rd_kiov(struct lnet_ni *ni, struct kib_tx *tx,
735                                 struct kib_rdma_desc *rd, int nkiov,
736                                 struct bio_vec *kiov, int offset, int nob)
737 {
738         struct kib_net *net = ni->ni_data;
739         struct scatterlist *sg;
740         int                 fragnob;
741         int                 max_nkiov;
742
743         CDEBUG(D_NET, "niov %d offset %d nob %d\n", nkiov, offset, nob);
744
745         LASSERT(nob > 0);
746         LASSERT(nkiov > 0);
747         LASSERT(net != NULL);
748
749         while (offset >= kiov->bv_len) {
750                 offset -= kiov->bv_len;
751                 nkiov--;
752                 kiov++;
753                 LASSERT(nkiov > 0);
754         }
755
756         max_nkiov = nkiov;
757
758         sg = tx->tx_frags;
759         do {
760                 LASSERT(nkiov > 0);
761
762                 fragnob = min((int)(kiov->bv_len - offset), nob);
763
764                 /*
765                  * We're allowed to start at a non-aligned page offset in
766                  * the first fragment and end at a non-aligned page offset
767                  * in the last fragment.
768                  */
769                 if ((fragnob < (int)(kiov->bv_len - offset)) &&
770                     nkiov < max_nkiov && nob > fragnob) {
771                         CDEBUG(D_NET, "fragnob %d < available page %d: with"
772                                       " remaining %d kiovs with %d nob left\n",
773                                fragnob, (int)(kiov->bv_len - offset),
774                                nkiov, nob);
775                         tx->tx_gaps = true;
776                 }
777
778                 sg_set_page(sg, kiov->bv_page, fragnob,
779                             kiov->bv_offset + offset);
780                 sg = sg_next(sg);
781                 if (!sg) {
782                         CERROR("lacking enough sg entries to map tx\n");
783                         return -EFAULT;
784                 }
785
786                 offset = 0;
787                 kiov++;
788                 nkiov--;
789                 nob -= fragnob;
790         } while (nob > 0);
791
792         return kiblnd_map_tx(ni, tx, rd, sg - tx->tx_frags);
793 }
794
795 static int
796 kiblnd_post_tx_locked(struct kib_conn *conn, struct kib_tx *tx, int credit)
797 __must_hold(&conn->ibc_lock)
798 {
799         struct kib_msg *msg = tx->tx_msg;
800         struct kib_peer_ni *peer_ni = conn->ibc_peer;
801         struct lnet_ni *ni = peer_ni->ibp_ni;
802         int ver = conn->ibc_version;
803         int rc;
804         int done;
805
806         LASSERT(tx->tx_queued);
807         /* We rely on this for QP sizing */
808         LASSERT(tx->tx_nwrq > 0 && tx->tx_nsge >= 0);
809         LASSERT(tx->tx_nwrq <= 1 + conn->ibc_max_frags);
810
811         LASSERT(credit == 0 || credit == 1);
812         LASSERT(conn->ibc_outstanding_credits >= 0);
813         LASSERT(conn->ibc_outstanding_credits <= conn->ibc_queue_depth);
814         LASSERT(conn->ibc_credits >= 0);
815         LASSERT(conn->ibc_credits <= conn->ibc_queue_depth);
816
817         if (conn->ibc_nsends_posted ==
818             kiblnd_concurrent_sends(ver, ni)) {
819                 /* tx completions outstanding... */
820                 CDEBUG(D_NET, "%s: posted enough\n",
821                        libcfs_nid2str(peer_ni->ibp_nid));
822                 return -EAGAIN;
823         }
824
825         if (credit != 0 && conn->ibc_credits == 0) {   /* no credits */
826                 CDEBUG(D_NET, "%s: no credits\n",
827                        libcfs_nid2str(peer_ni->ibp_nid));
828                 return -EAGAIN;
829         }
830
831         if (credit != 0 && !IBLND_OOB_CAPABLE(ver) &&
832             conn->ibc_credits == 1 &&   /* last credit reserved */
833             msg->ibm_type != IBLND_MSG_NOOP) {      /* for NOOP */
834                 CDEBUG(D_NET, "%s: not using last credit\n",
835                        libcfs_nid2str(peer_ni->ibp_nid));
836                 return -EAGAIN;
837         }
838
839         /* NB don't drop ibc_lock before bumping tx_sending */
840         list_del(&tx->tx_list);
841         tx->tx_queued = 0;
842
843         if (msg->ibm_type == IBLND_MSG_NOOP &&
844             (!kiblnd_need_noop(conn) ||     /* redundant NOOP */
845              (IBLND_OOB_CAPABLE(ver) && /* posted enough NOOP */
846               conn->ibc_noops_posted == IBLND_OOB_MSGS(ver)))) {
847                 /* OK to drop when posted enough NOOPs, since
848                  * kiblnd_check_sends_locked will queue NOOP again when
849                  * posted NOOPs complete */
850                 spin_unlock(&conn->ibc_lock);
851                 tx->tx_hstatus = LNET_MSG_STATUS_LOCAL_ERROR;
852                 kiblnd_tx_done(tx);
853                 spin_lock(&conn->ibc_lock);
854                 CDEBUG(D_NET, "%s(%d): redundant or enough NOOP\n",
855                        libcfs_nid2str(peer_ni->ibp_nid),
856                        conn->ibc_noops_posted);
857                 return 0;
858         }
859
860         kiblnd_pack_msg(peer_ni->ibp_ni, msg, ver, conn->ibc_outstanding_credits,
861                         peer_ni->ibp_nid, conn->ibc_incarnation);
862
863         conn->ibc_credits -= credit;
864         conn->ibc_outstanding_credits = 0;
865         conn->ibc_nsends_posted++;
866         if (msg->ibm_type == IBLND_MSG_NOOP)
867                 conn->ibc_noops_posted++;
868
869         /* CAVEAT EMPTOR!  This tx could be the PUT_DONE of an RDMA
870          * PUT.  If so, it was first queued here as a PUT_REQ, sent and
871          * stashed on ibc_active_txs, matched by an incoming PUT_ACK,
872          * and then re-queued here.  It's (just) possible that
873          * tx_sending is non-zero if we've not done the tx_complete()
874          * from the first send; hence the ++ rather than = below. */
875         tx->tx_sending++;
876         list_add(&tx->tx_list, &conn->ibc_active_txs);
877
878         /* I'm still holding ibc_lock! */
879         if (conn->ibc_state != IBLND_CONN_ESTABLISHED) {
880                 rc = -ECONNABORTED;
881         } else if (tx->tx_pool->tpo_pool.po_failed ||
882                  conn->ibc_hdev != tx->tx_pool->tpo_hdev) {
883                 /* close_conn will launch failover */
884                 rc = -ENETDOWN;
885         } else {
886                 struct kib_fast_reg_descriptor *frd = tx->tx_fmr.fmr_frd;
887                 struct ib_send_wr *bad = &tx->tx_wrq[tx->tx_nwrq - 1].wr;
888                 struct ib_send_wr *wr  = &tx->tx_wrq[0].wr;
889
890                 if (frd != NULL) {
891                         if (!frd->frd_valid) {
892                                 wr = &frd->frd_inv_wr.wr;
893                                 wr->next = &frd->frd_fastreg_wr.wr;
894                         } else {
895                                 wr = &frd->frd_fastreg_wr.wr;
896                         }
897                         frd->frd_fastreg_wr.wr.next = &tx->tx_wrq[0].wr;
898                 }
899
900                 LASSERTF(bad->wr_id == kiblnd_ptr2wreqid(tx, IBLND_WID_TX),
901                          "bad wr_id %#llx, opc %d, flags %d, peer_ni: %s\n",
902                          bad->wr_id, bad->opcode, bad->send_flags,
903                          libcfs_nid2str(conn->ibc_peer->ibp_nid));
904
905                 bad = NULL;
906                 if (lnet_send_error_simulation(tx->tx_lntmsg[0], &tx->tx_hstatus))
907                         rc = -EINVAL;
908                 else
909 #ifdef HAVE_IB_POST_SEND_RECV_CONST
910                         rc = ib_post_send(conn->ibc_cmid->qp, wr,
911                                           (const struct ib_send_wr **)&bad);
912 #else
913                         rc = ib_post_send(conn->ibc_cmid->qp, wr, &bad);
914 #endif
915         }
916
917         conn->ibc_last_send = ktime_get();
918
919         if (rc == 0)
920                 return 0;
921
922         /* NB credits are transferred in the actual
923          * message, which can only be the last work item */
924         conn->ibc_credits += credit;
925         conn->ibc_outstanding_credits += msg->ibm_credits;
926         conn->ibc_nsends_posted--;
927         if (msg->ibm_type == IBLND_MSG_NOOP)
928                 conn->ibc_noops_posted--;
929
930         tx->tx_status = rc;
931         tx->tx_waiting = 0;
932         tx->tx_sending--;
933
934         done = (tx->tx_sending == 0);
935         if (done)
936                 list_del(&tx->tx_list);
937
938         spin_unlock(&conn->ibc_lock);
939
940         if (conn->ibc_state == IBLND_CONN_ESTABLISHED)
941                 CERROR("Error %d posting transmit to %s\n",
942                        rc, libcfs_nid2str(peer_ni->ibp_nid));
943         else
944                 CDEBUG(D_NET, "Error %d posting transmit to %s\n",
945                        rc, libcfs_nid2str(peer_ni->ibp_nid));
946
947         kiblnd_close_conn(conn, rc);
948
949         if (done)
950                 kiblnd_tx_done(tx);
951
952         spin_lock(&conn->ibc_lock);
953
954         return -EIO;
955 }
956
957 static void
958 kiblnd_check_sends_locked(struct kib_conn *conn)
959 {
960         int ver = conn->ibc_version;
961         struct lnet_ni *ni = conn->ibc_peer->ibp_ni;
962         struct kib_tx *tx;
963
964         /* Don't send anything until after the connection is established */
965         if (conn->ibc_state < IBLND_CONN_ESTABLISHED) {
966                 CDEBUG(D_NET, "%s too soon\n",
967                        libcfs_nid2str(conn->ibc_peer->ibp_nid));
968                 return;
969         }
970
971         LASSERT(conn->ibc_nsends_posted <=
972                 kiblnd_concurrent_sends(ver, ni));
973         LASSERT (!IBLND_OOB_CAPABLE(ver) ||
974                  conn->ibc_noops_posted <= IBLND_OOB_MSGS(ver));
975         LASSERT (conn->ibc_reserved_credits >= 0);
976
977         while (conn->ibc_reserved_credits > 0 &&
978                !list_empty(&conn->ibc_tx_queue_rsrvd)) {
979                 tx = list_entry(conn->ibc_tx_queue_rsrvd.next,
980                                 struct kib_tx, tx_list);
981                 list_move_tail(&tx->tx_list, &conn->ibc_tx_queue);
982                 conn->ibc_reserved_credits--;
983         }
984
985         if (kiblnd_need_noop(conn)) {
986                 spin_unlock(&conn->ibc_lock);
987
988                 tx = kiblnd_get_idle_tx(ni, conn->ibc_peer->ibp_nid);
989                 if (tx != NULL)
990                         kiblnd_init_tx_msg(ni, tx, IBLND_MSG_NOOP, 0);
991
992                 spin_lock(&conn->ibc_lock);
993                 if (tx != NULL)
994                         kiblnd_queue_tx_locked(tx, conn);
995         }
996
997         for (;;) {
998                 int credit;
999
1000                 if (!list_empty(&conn->ibc_tx_queue_nocred)) {
1001                         credit = 0;
1002                         tx = list_entry(conn->ibc_tx_queue_nocred.next,
1003                                         struct kib_tx, tx_list);
1004                 } else if (!list_empty(&conn->ibc_tx_noops)) {
1005                         LASSERT (!IBLND_OOB_CAPABLE(ver));
1006                         credit = 1;
1007                         tx = list_entry(conn->ibc_tx_noops.next,
1008                                         struct kib_tx, tx_list);
1009                 } else if (!list_empty(&conn->ibc_tx_queue)) {
1010                         credit = 1;
1011                         tx = list_entry(conn->ibc_tx_queue.next,
1012                                         struct kib_tx, tx_list);
1013                 } else
1014                         break;
1015
1016                 if (kiblnd_post_tx_locked(conn, tx, credit) != 0)
1017                         break;
1018         }
1019 }
1020
1021 static void
1022 kiblnd_tx_complete(struct kib_tx *tx, int status)
1023 {
1024         int           failed = (status != IB_WC_SUCCESS);
1025         struct kib_conn   *conn = tx->tx_conn;
1026         int           idle;
1027
1028         if (tx->tx_sending <= 0) {
1029                 CERROR("Received an event on a freed tx: %p status %d\n",
1030                        tx, tx->tx_status);
1031                 return;
1032         }
1033
1034         if (failed) {
1035                 if (conn->ibc_state == IBLND_CONN_ESTABLISHED)
1036                         CNETERR("Tx -> %s cookie %#llx"
1037                                 " sending %d waiting %d: failed %d\n",
1038                                 libcfs_nid2str(conn->ibc_peer->ibp_nid),
1039                                 tx->tx_cookie, tx->tx_sending, tx->tx_waiting,
1040                                 status);
1041
1042                 kiblnd_close_conn(conn, -EIO);
1043         } else {
1044                 kiblnd_peer_alive(conn->ibc_peer);
1045         }
1046
1047         spin_lock(&conn->ibc_lock);
1048
1049         /* I could be racing with rdma completion.  Whoever makes 'tx' idle
1050          * gets to free it, which also drops its ref on 'conn'. */
1051
1052         tx->tx_sending--;
1053         conn->ibc_nsends_posted--;
1054         if (tx->tx_msg->ibm_type == IBLND_MSG_NOOP)
1055                 conn->ibc_noops_posted--;
1056
1057         if (failed) {
1058                 tx->tx_hstatus = LNET_MSG_STATUS_REMOTE_DROPPED;
1059                 tx->tx_waiting = 0;             /* don't wait for peer_ni */
1060                 tx->tx_status = -EIO;
1061         }
1062
1063         idle = (tx->tx_sending == 0) &&         /* This is the final callback */
1064                !tx->tx_waiting &&               /* Not waiting for peer_ni */
1065                !tx->tx_queued;                  /* Not re-queued (PUT_DONE) */
1066         if (idle)
1067                 list_del(&tx->tx_list);
1068
1069         kiblnd_check_sends_locked(conn);
1070         spin_unlock(&conn->ibc_lock);
1071
1072         if (idle)
1073                 kiblnd_tx_done(tx);
1074 }
1075
1076 static void
1077 kiblnd_init_tx_msg(struct lnet_ni *ni, struct kib_tx *tx, int type,
1078                    int body_nob)
1079 {
1080         struct kib_hca_dev *hdev = tx->tx_pool->tpo_hdev;
1081         struct ib_sge *sge = &tx->tx_msgsge;
1082         struct ib_rdma_wr *wrq;
1083         int nob = offsetof(struct kib_msg, ibm_u) + body_nob;
1084 #ifdef HAVE_IB_GET_DMA_MR
1085         struct ib_mr *mr = hdev->ibh_mrs;
1086 #endif
1087
1088         LASSERT(tx->tx_nwrq >= 0);
1089         LASSERT(tx->tx_nwrq < IBLND_MAX_RDMA_FRAGS + 1);
1090         LASSERT(nob <= IBLND_MSG_SIZE);
1091 #ifdef HAVE_IB_GET_DMA_MR
1092         LASSERT(mr != NULL);
1093 #endif
1094
1095         kiblnd_init_msg(tx->tx_msg, type, body_nob);
1096
1097 #ifdef HAVE_IB_GET_DMA_MR
1098         sge->lkey   = mr->lkey;
1099 #else
1100         sge->lkey   = hdev->ibh_pd->local_dma_lkey;
1101 #endif
1102         sge->addr   = tx->tx_msgaddr;
1103         sge->length = nob;
1104
1105         wrq = &tx->tx_wrq[tx->tx_nwrq];
1106         memset(wrq, 0, sizeof(*wrq));
1107
1108         wrq->wr.next            = NULL;
1109         wrq->wr.wr_id           = kiblnd_ptr2wreqid(tx, IBLND_WID_TX);
1110         wrq->wr.sg_list         = sge;
1111         wrq->wr.num_sge         = 1;
1112         wrq->wr.opcode          = IB_WR_SEND;
1113         wrq->wr.send_flags      = IB_SEND_SIGNALED;
1114
1115         tx->tx_nwrq++;
1116 }
1117
1118 static int
1119 kiblnd_init_rdma(struct kib_conn *conn, struct kib_tx *tx, int type,
1120                  int resid, struct kib_rdma_desc *dstrd, u64 dstcookie)
1121 {
1122         struct kib_msg *ibmsg = tx->tx_msg;
1123         struct kib_rdma_desc *srcrd = tx->tx_rd;
1124         struct ib_rdma_wr *wrq = NULL;
1125         struct ib_sge     *sge;
1126         int                rc  = resid;
1127         int                srcidx;
1128         int                dstidx;
1129         int                sge_nob;
1130         int                wrq_sge;
1131
1132         LASSERT(!in_interrupt());
1133         LASSERT(tx->tx_nwrq == 0 && tx->tx_nsge == 0);
1134         LASSERT(type == IBLND_MSG_GET_DONE || type == IBLND_MSG_PUT_DONE);
1135
1136         for (srcidx = dstidx = wrq_sge = sge_nob = 0;
1137              resid > 0; resid -= sge_nob) {
1138                 int     prev = dstidx;
1139
1140                 if (srcidx >= srcrd->rd_nfrags) {
1141                         CERROR("Src buffer exhausted: %d frags\n", srcidx);
1142                         rc = -EPROTO;
1143                         break;
1144                 }
1145
1146                 if (dstidx >= dstrd->rd_nfrags) {
1147                         CERROR("Dst buffer exhausted: %d frags\n", dstidx);
1148                         rc = -EPROTO;
1149                         break;
1150                 }
1151
1152                 if (tx->tx_nwrq >= conn->ibc_max_frags) {
1153                         CERROR("RDMA has too many fragments for peer_ni %s (%d), "
1154                                "src idx/frags: %d/%d dst idx/frags: %d/%d\n",
1155                                libcfs_nid2str(conn->ibc_peer->ibp_nid),
1156                                conn->ibc_max_frags,
1157                                srcidx, srcrd->rd_nfrags,
1158                                dstidx, dstrd->rd_nfrags);
1159                         rc = -EMSGSIZE;
1160                         break;
1161                 }
1162
1163                 sge_nob = min3(kiblnd_rd_frag_size(srcrd, srcidx),
1164                                kiblnd_rd_frag_size(dstrd, dstidx),
1165                                resid);
1166
1167                 sge = &tx->tx_sge[tx->tx_nsge];
1168                 sge->addr   = kiblnd_rd_frag_addr(srcrd, srcidx);
1169                 sge->lkey   = kiblnd_rd_frag_key(srcrd, srcidx);
1170                 sge->length = sge_nob;
1171
1172                 if (wrq_sge == 0) {
1173                         wrq = &tx->tx_wrq[tx->tx_nwrq];
1174
1175                         wrq->wr.next    = &(wrq + 1)->wr;
1176                         wrq->wr.wr_id   = kiblnd_ptr2wreqid(tx, IBLND_WID_RDMA);
1177                         wrq->wr.sg_list = sge;
1178                         wrq->wr.opcode  = IB_WR_RDMA_WRITE;
1179                         wrq->wr.send_flags = 0;
1180
1181 #ifdef HAVE_IB_RDMA_WR
1182                         wrq->remote_addr        = kiblnd_rd_frag_addr(dstrd,
1183                                                                       dstidx);
1184                         wrq->rkey               = kiblnd_rd_frag_key(dstrd,
1185                                                                      dstidx);
1186 #else
1187                         wrq->wr.wr.rdma.remote_addr = kiblnd_rd_frag_addr(dstrd,
1188                                                                         dstidx);
1189                         wrq->wr.wr.rdma.rkey    = kiblnd_rd_frag_key(dstrd,
1190                                                                      dstidx);
1191 #endif
1192                 }
1193
1194                 srcidx = kiblnd_rd_consume_frag(srcrd, srcidx, sge_nob);
1195                 dstidx = kiblnd_rd_consume_frag(dstrd, dstidx, sge_nob);
1196
1197                 wrq_sge++;
1198                 if (wrq_sge == *kiblnd_tunables.kib_wrq_sge || dstidx != prev) {
1199                         tx->tx_nwrq++;
1200                         wrq->wr.num_sge = wrq_sge;
1201                         wrq_sge = 0;
1202                 }
1203                 tx->tx_nsge++;
1204         }
1205
1206         if (rc < 0)     /* no RDMA if completing with failure */
1207                 tx->tx_nwrq = tx->tx_nsge = 0;
1208
1209         ibmsg->ibm_u.completion.ibcm_status = rc;
1210         ibmsg->ibm_u.completion.ibcm_cookie = dstcookie;
1211         kiblnd_init_tx_msg(conn->ibc_peer->ibp_ni, tx,
1212                            type, sizeof(struct kib_completion_msg));
1213
1214         return rc;
1215 }
1216
1217 static void
1218 kiblnd_queue_tx_locked(struct kib_tx *tx, struct kib_conn *conn)
1219 {
1220         struct list_head *q;
1221         s64 timeout_ns;
1222
1223         LASSERT(tx->tx_nwrq > 0);       /* work items set up */
1224         LASSERT(!tx->tx_queued);        /* not queued for sending already */
1225         LASSERT(conn->ibc_state >= IBLND_CONN_ESTABLISHED);
1226
1227         if (conn->ibc_state >= IBLND_CONN_DISCONNECTED) {
1228                 tx->tx_status = -ECONNABORTED;
1229                 tx->tx_waiting = 0;
1230                 if (tx->tx_conn != NULL) {
1231                         /* PUT_DONE first attached to conn as a PUT_REQ */
1232                         LASSERT(tx->tx_conn == conn);
1233                         LASSERT(tx->tx_msg->ibm_type == IBLND_MSG_PUT_DONE);
1234                         tx->tx_conn = NULL;
1235                         kiblnd_conn_decref(conn);
1236                 }
1237                 list_add(&tx->tx_list, &conn->ibc_zombie_txs);
1238
1239                 return;
1240         }
1241
1242         timeout_ns = kiblnd_timeout() * NSEC_PER_SEC;
1243         tx->tx_queued = 1;
1244         tx->tx_deadline = ktime_add_ns(ktime_get(), timeout_ns);
1245
1246         if (tx->tx_conn == NULL) {
1247                 kiblnd_conn_addref(conn);
1248                 tx->tx_conn = conn;
1249                 LASSERT (tx->tx_msg->ibm_type != IBLND_MSG_PUT_DONE);
1250         } else {
1251                 /* PUT_DONE first attached to conn as a PUT_REQ */
1252                 LASSERT (tx->tx_conn == conn);
1253                 LASSERT (tx->tx_msg->ibm_type == IBLND_MSG_PUT_DONE);
1254         }
1255
1256         switch (tx->tx_msg->ibm_type) {
1257         default:
1258                 LBUG();
1259
1260         case IBLND_MSG_PUT_REQ:
1261         case IBLND_MSG_GET_REQ:
1262                 q = &conn->ibc_tx_queue_rsrvd;
1263                 break;
1264
1265         case IBLND_MSG_PUT_NAK:
1266         case IBLND_MSG_PUT_ACK:
1267         case IBLND_MSG_PUT_DONE:
1268         case IBLND_MSG_GET_DONE:
1269                 q = &conn->ibc_tx_queue_nocred;
1270                 break;
1271
1272         case IBLND_MSG_NOOP:
1273                 if (IBLND_OOB_CAPABLE(conn->ibc_version))
1274                         q = &conn->ibc_tx_queue_nocred;
1275                 else
1276                         q = &conn->ibc_tx_noops;
1277                 break;
1278
1279         case IBLND_MSG_IMMEDIATE:
1280                 q = &conn->ibc_tx_queue;
1281                 break;
1282         }
1283
1284         list_add_tail(&tx->tx_list, q);
1285 }
1286
1287 static void
1288 kiblnd_queue_tx(struct kib_tx *tx, struct kib_conn *conn)
1289 {
1290         spin_lock(&conn->ibc_lock);
1291         kiblnd_queue_tx_locked(tx, conn);
1292         kiblnd_check_sends_locked(conn);
1293         spin_unlock(&conn->ibc_lock);
1294 }
1295
1296 static int kiblnd_resolve_addr(struct rdma_cm_id *cmid,
1297                                struct sockaddr_in *srcaddr,
1298                                struct sockaddr_in *dstaddr,
1299                                int timeout_ms)
1300 {
1301         unsigned short port;
1302         int rc;
1303
1304         /* allow the port to be reused */
1305         rc = rdma_set_reuseaddr(cmid, 1);
1306         if (rc != 0) {
1307                 CERROR("Unable to set reuse on cmid: %d\n", rc);
1308                 return rc;
1309         }
1310
1311         /* look for a free privileged port */
1312         for (port = PROT_SOCK-1; port > 0; port--) {
1313                 srcaddr->sin_port = htons(port);
1314                 rc = rdma_resolve_addr(cmid,
1315                                        (struct sockaddr *)srcaddr,
1316                                        (struct sockaddr *)dstaddr,
1317                                        timeout_ms);
1318                 if (rc == 0) {
1319                         CDEBUG(D_NET, "bound to port %hu\n", port);
1320                         return 0;
1321                 } else if (rc == -EADDRINUSE || rc == -EADDRNOTAVAIL) {
1322                         CDEBUG(D_NET, "bind to port %hu failed: %d\n",
1323                                port, rc);
1324                 } else {
1325                         return rc;
1326                 }
1327         }
1328
1329         CERROR("Failed to bind to a free privileged port\n");
1330         return rc;
1331 }
1332
1333 static void
1334 kiblnd_connect_peer(struct kib_peer_ni *peer_ni)
1335 {
1336         struct rdma_cm_id *cmid;
1337         struct kib_dev *dev;
1338         struct kib_net *net = peer_ni->ibp_ni->ni_data;
1339         struct sockaddr_in srcaddr;
1340         struct sockaddr_in dstaddr;
1341         int rc;
1342
1343         LASSERT (net != NULL);
1344         LASSERT (peer_ni->ibp_connecting > 0);
1345
1346         cmid = kiblnd_rdma_create_id(peer_ni->ibp_ni->ni_net_ns,
1347                                      kiblnd_cm_callback, peer_ni,
1348                                      RDMA_PS_TCP, IB_QPT_RC);
1349
1350         if (IS_ERR(cmid)) {
1351                 CERROR("Can't create CMID for %s: %ld\n",
1352                        libcfs_nid2str(peer_ni->ibp_nid), PTR_ERR(cmid));
1353                 rc = PTR_ERR(cmid);
1354                 goto failed;
1355         }
1356
1357         dev = net->ibn_dev;
1358         memset(&srcaddr, 0, sizeof(srcaddr));
1359         srcaddr.sin_family = AF_INET;
1360         srcaddr.sin_addr.s_addr = htonl(dev->ibd_ifip);
1361
1362         memset(&dstaddr, 0, sizeof(dstaddr));
1363         dstaddr.sin_family = AF_INET;
1364         dstaddr.sin_port = htons(*kiblnd_tunables.kib_service);
1365         dstaddr.sin_addr.s_addr = htonl(LNET_NIDADDR(peer_ni->ibp_nid));
1366
1367         kiblnd_peer_addref(peer_ni);               /* cmid's ref */
1368
1369         if (*kiblnd_tunables.kib_use_priv_port) {
1370                 rc = kiblnd_resolve_addr(cmid, &srcaddr, &dstaddr,
1371                                          kiblnd_timeout() * 1000);
1372         } else {
1373                 rc = rdma_resolve_addr(cmid,
1374                                        (struct sockaddr *)&srcaddr,
1375                                        (struct sockaddr *)&dstaddr,
1376                                        kiblnd_timeout() * 1000);
1377         }
1378         if (rc != 0) {
1379                 /* Can't initiate address resolution:  */
1380                 CERROR("Can't resolve addr for %s: %d\n",
1381                        libcfs_nid2str(peer_ni->ibp_nid), rc);
1382                 goto failed2;
1383         }
1384
1385         return;
1386
1387  failed2:
1388         kiblnd_peer_connect_failed(peer_ni, 1, rc);
1389         kiblnd_peer_decref(peer_ni);               /* cmid's ref */
1390         rdma_destroy_id(cmid);
1391         return;
1392  failed:
1393         kiblnd_peer_connect_failed(peer_ni, 1, rc);
1394 }
1395
1396 bool
1397 kiblnd_reconnect_peer(struct kib_peer_ni *peer_ni)
1398 {
1399         rwlock_t *glock = &kiblnd_data.kib_global_lock;
1400         char *reason = NULL;
1401         LIST_HEAD(txs);
1402         unsigned long flags;
1403
1404         write_lock_irqsave(glock, flags);
1405         if (peer_ni->ibp_reconnecting == 0) {
1406                 if (peer_ni->ibp_accepting)
1407                         reason = "accepting";
1408                 else if (peer_ni->ibp_connecting)
1409                         reason = "connecting";
1410                 else if (!list_empty(&peer_ni->ibp_conns))
1411                         reason = "connected";
1412                 else /* connected then closed */
1413                         reason = "closed";
1414
1415                 goto no_reconnect;
1416         }
1417
1418         if (peer_ni->ibp_accepting)
1419                 CNETERR("Detecting race between accepting and reconnecting\n");
1420         peer_ni->ibp_reconnecting--;
1421
1422         if (!kiblnd_peer_active(peer_ni)) {
1423                 list_splice_init(&peer_ni->ibp_tx_queue, &txs);
1424                 reason = "unlinked";
1425                 goto no_reconnect;
1426         }
1427
1428         peer_ni->ibp_connecting++;
1429         peer_ni->ibp_reconnected++;
1430
1431         write_unlock_irqrestore(glock, flags);
1432
1433         kiblnd_connect_peer(peer_ni);
1434         return true;
1435
1436  no_reconnect:
1437         write_unlock_irqrestore(glock, flags);
1438
1439         CWARN("Abort reconnection of %s: %s\n",
1440               libcfs_nid2str(peer_ni->ibp_nid), reason);
1441         kiblnd_txlist_done(&txs, -ECONNABORTED,
1442                            LNET_MSG_STATUS_LOCAL_ABORTED);
1443         return false;
1444 }
1445
1446 void
1447 kiblnd_launch_tx(struct lnet_ni *ni, struct kib_tx *tx, lnet_nid_t nid)
1448 {
1449         struct kib_peer_ni *peer_ni;
1450         struct kib_peer_ni *peer2;
1451         struct kib_conn *conn;
1452         rwlock_t *g_lock = &kiblnd_data.kib_global_lock;
1453         unsigned long      flags;
1454         int                rc;
1455         int                i;
1456         struct lnet_ioctl_config_o2iblnd_tunables *tunables;
1457
1458         /* If I get here, I've committed to send, so I complete the tx with
1459          * failure on any problems */
1460
1461         LASSERT (tx == NULL || tx->tx_conn == NULL); /* only set when assigned a conn */
1462         LASSERT (tx == NULL || tx->tx_nwrq > 0);     /* work items have been set up */
1463
1464         /* First time, just use a read lock since I expect to find my peer_ni
1465          * connected */
1466         read_lock_irqsave(g_lock, flags);
1467
1468         peer_ni = kiblnd_find_peer_locked(ni, nid);
1469         if (peer_ni != NULL && !list_empty(&peer_ni->ibp_conns)) {
1470                 /* Found a peer_ni with an established connection */
1471                 conn = kiblnd_get_conn_locked(peer_ni);
1472                 kiblnd_conn_addref(conn); /* 1 ref for me... */
1473
1474                 read_unlock_irqrestore(g_lock, flags);
1475
1476                 if (tx != NULL)
1477                         kiblnd_queue_tx(tx, conn);
1478                 kiblnd_conn_decref(conn); /* ...to here */
1479                 return;
1480         }
1481
1482         read_unlock(g_lock);
1483         /* Re-try with a write lock */
1484         write_lock(g_lock);
1485
1486         peer_ni = kiblnd_find_peer_locked(ni, nid);
1487         if (peer_ni != NULL) {
1488                 if (list_empty(&peer_ni->ibp_conns)) {
1489                         /* found a peer_ni, but it's still connecting... */
1490                         LASSERT(kiblnd_peer_connecting(peer_ni));
1491                         if (tx != NULL)
1492                                 list_add_tail(&tx->tx_list,
1493                                                   &peer_ni->ibp_tx_queue);
1494                         write_unlock_irqrestore(g_lock, flags);
1495                 } else {
1496                         conn = kiblnd_get_conn_locked(peer_ni);
1497                         kiblnd_conn_addref(conn); /* 1 ref for me... */
1498
1499                         write_unlock_irqrestore(g_lock, flags);
1500
1501                         if (tx != NULL)
1502                                 kiblnd_queue_tx(tx, conn);
1503                         kiblnd_conn_decref(conn); /* ...to here */
1504                 }
1505                 return;
1506         }
1507
1508         write_unlock_irqrestore(g_lock, flags);
1509
1510         /* Allocate a peer_ni ready to add to the peer_ni table and retry */
1511         rc = kiblnd_create_peer(ni, &peer_ni, nid);
1512         if (rc != 0) {
1513                 CERROR("Can't create peer_ni %s\n", libcfs_nid2str(nid));
1514                 if (tx != NULL) {
1515                         tx->tx_status = -EHOSTUNREACH;
1516                         tx->tx_waiting = 0;
1517                         tx->tx_hstatus = LNET_MSG_STATUS_LOCAL_ERROR;
1518                         kiblnd_tx_done(tx);
1519                 }
1520                 return;
1521         }
1522
1523         write_lock_irqsave(g_lock, flags);
1524
1525         peer2 = kiblnd_find_peer_locked(ni, nid);
1526         if (peer2 != NULL) {
1527                 if (list_empty(&peer2->ibp_conns)) {
1528                         /* found a peer_ni, but it's still connecting... */
1529                         LASSERT(kiblnd_peer_connecting(peer2));
1530                         if (tx != NULL)
1531                                 list_add_tail(&tx->tx_list,
1532                                                   &peer2->ibp_tx_queue);
1533                         write_unlock_irqrestore(g_lock, flags);
1534                 } else {
1535                         conn = kiblnd_get_conn_locked(peer2);
1536                         kiblnd_conn_addref(conn); /* 1 ref for me... */
1537
1538                         write_unlock_irqrestore(g_lock, flags);
1539
1540                         if (tx != NULL)
1541                                 kiblnd_queue_tx(tx, conn);
1542                         kiblnd_conn_decref(conn); /* ...to here */
1543                 }
1544
1545                 kiblnd_peer_decref(peer_ni);
1546                 return;
1547         }
1548
1549         /* Brand new peer_ni */
1550         LASSERT(peer_ni->ibp_connecting == 0);
1551         tunables = &peer_ni->ibp_ni->ni_lnd_tunables.lnd_tun_u.lnd_o2ib;
1552         peer_ni->ibp_connecting = tunables->lnd_conns_per_peer;
1553
1554         /* always called with a ref on ni, which prevents ni being shutdown */
1555         LASSERT(((struct kib_net *)ni->ni_data)->ibn_shutdown == 0);
1556
1557         if (tx != NULL)
1558                 list_add_tail(&tx->tx_list, &peer_ni->ibp_tx_queue);
1559
1560         kiblnd_peer_addref(peer_ni);
1561         list_add_tail(&peer_ni->ibp_list, kiblnd_nid2peerlist(nid));
1562
1563         write_unlock_irqrestore(g_lock, flags);
1564
1565         for (i = 0; i < tunables->lnd_conns_per_peer; i++)
1566                 kiblnd_connect_peer(peer_ni);
1567         kiblnd_peer_decref(peer_ni);
1568 }
1569
1570 int
1571 kiblnd_send(struct lnet_ni *ni, void *private, struct lnet_msg *lntmsg)
1572 {
1573         struct lnet_hdr *hdr = &lntmsg->msg_hdr;
1574         int               type = lntmsg->msg_type;
1575         struct lnet_process_id target = lntmsg->msg_target;
1576         int               target_is_router = lntmsg->msg_target_is_router;
1577         int               routing = lntmsg->msg_routing;
1578         unsigned int      payload_niov = lntmsg->msg_niov;
1579         struct bio_vec   *payload_kiov = lntmsg->msg_kiov;
1580         unsigned int      payload_offset = lntmsg->msg_offset;
1581         unsigned int      payload_nob = lntmsg->msg_len;
1582         struct kib_msg *ibmsg;
1583         struct kib_rdma_desc *rd;
1584         struct kib_tx *tx;
1585         int               nob;
1586         int               rc;
1587
1588         /* NB 'private' is different depending on what we're sending.... */
1589
1590         CDEBUG(D_NET, "sending %d bytes in %d frags to %s\n",
1591                payload_nob, payload_niov, libcfs_id2str(target));
1592
1593         LASSERT (payload_nob == 0 || payload_niov > 0);
1594         LASSERT (payload_niov <= LNET_MAX_IOV);
1595
1596         /* Thread context */
1597         LASSERT (!in_interrupt());
1598
1599         switch (type) {
1600         default:
1601                 LBUG();
1602                 return (-EIO);
1603
1604         case LNET_MSG_ACK:
1605                 LASSERT (payload_nob == 0);
1606                 break;
1607
1608         case LNET_MSG_GET:
1609                 if (routing || target_is_router)
1610                         break;                  /* send IMMEDIATE */
1611
1612                 /* is the REPLY message too small for RDMA? */
1613                 nob = offsetof(struct kib_msg, ibm_u.immediate.ibim_payload[lntmsg->msg_md->md_length]);
1614                 if (nob <= IBLND_MSG_SIZE)
1615                         break;                  /* send IMMEDIATE */
1616
1617                 tx = kiblnd_get_idle_tx(ni, target.nid);
1618                 if (tx == NULL) {
1619                         CERROR("Can't allocate txd for GET to %s\n",
1620                                libcfs_nid2str(target.nid));
1621                         return -ENOMEM;
1622                 }
1623
1624                 ibmsg = tx->tx_msg;
1625                 rd = &ibmsg->ibm_u.get.ibgm_rd;
1626                 rc = kiblnd_setup_rd_kiov(ni, tx, rd,
1627                                           lntmsg->msg_md->md_niov,
1628                                           lntmsg->msg_md->md_kiov,
1629                                           0, lntmsg->msg_md->md_length);
1630                 if (rc != 0) {
1631                         CERROR("Can't setup GET sink for %s: %d\n",
1632                                libcfs_nid2str(target.nid), rc);
1633                         tx->tx_hstatus = LNET_MSG_STATUS_LOCAL_ERROR;
1634                         kiblnd_tx_done(tx);
1635                         return -EIO;
1636                 }
1637
1638                 nob = offsetof(struct kib_get_msg, ibgm_rd.rd_frags[rd->rd_nfrags]);
1639                 ibmsg->ibm_u.get.ibgm_cookie = tx->tx_cookie;
1640                 ibmsg->ibm_u.get.ibgm_hdr = *hdr;
1641
1642                 kiblnd_init_tx_msg(ni, tx, IBLND_MSG_GET_REQ, nob);
1643
1644                 tx->tx_lntmsg[1] = lnet_create_reply_msg(ni, lntmsg);
1645                 if (tx->tx_lntmsg[1] == NULL) {
1646                         CERROR("Can't create reply for GET -> %s\n",
1647                                libcfs_nid2str(target.nid));
1648                         kiblnd_tx_done(tx);
1649                         return -EIO;
1650                 }
1651
1652                 tx->tx_lntmsg[0] = lntmsg;      /* finalise lntmsg[0,1] on completion */
1653                 tx->tx_waiting = 1;             /* waiting for GET_DONE */
1654                 kiblnd_launch_tx(ni, tx, target.nid);
1655                 return 0;
1656
1657         case LNET_MSG_REPLY:
1658         case LNET_MSG_PUT:
1659                 /* Is the payload small enough not to need RDMA? */
1660                 nob = offsetof(struct kib_msg, ibm_u.immediate.ibim_payload[payload_nob]);
1661                 if (nob <= IBLND_MSG_SIZE)
1662                         break;                  /* send IMMEDIATE */
1663
1664                 tx = kiblnd_get_idle_tx(ni, target.nid);
1665                 if (tx == NULL) {
1666                         CERROR("Can't allocate %s txd for %s\n",
1667                                type == LNET_MSG_PUT ? "PUT" : "REPLY",
1668                                libcfs_nid2str(target.nid));
1669                         return -ENOMEM;
1670                 }
1671
1672                 rc = kiblnd_setup_rd_kiov(ni, tx, tx->tx_rd,
1673                                           payload_niov, payload_kiov,
1674                                           payload_offset, payload_nob);
1675                 if (rc != 0) {
1676                         CERROR("Can't setup PUT src for %s: %d\n",
1677                                libcfs_nid2str(target.nid), rc);
1678                         kiblnd_tx_done(tx);
1679                         return -EIO;
1680                 }
1681
1682                 ibmsg = tx->tx_msg;
1683                 ibmsg->ibm_u.putreq.ibprm_hdr = *hdr;
1684                 ibmsg->ibm_u.putreq.ibprm_cookie = tx->tx_cookie;
1685                 kiblnd_init_tx_msg(ni, tx, IBLND_MSG_PUT_REQ,
1686                                    sizeof(struct kib_putreq_msg));
1687
1688                 tx->tx_lntmsg[0] = lntmsg;      /* finalise lntmsg on completion */
1689                 tx->tx_waiting = 1;             /* waiting for PUT_{ACK,NAK} */
1690                 kiblnd_launch_tx(ni, tx, target.nid);
1691                 return 0;
1692         }
1693
1694         /* send IMMEDIATE */
1695         LASSERT(offsetof(struct kib_msg, ibm_u.immediate.ibim_payload[payload_nob])
1696                 <= IBLND_MSG_SIZE);
1697
1698         tx = kiblnd_get_idle_tx(ni, target.nid);
1699         if (tx == NULL) {
1700                 CERROR ("Can't send %d to %s: tx descs exhausted\n",
1701                         type, libcfs_nid2str(target.nid));
1702                 return -ENOMEM;
1703         }
1704
1705         ibmsg = tx->tx_msg;
1706         ibmsg->ibm_u.immediate.ibim_hdr = *hdr;
1707
1708         lnet_copy_kiov2flat(IBLND_MSG_SIZE, ibmsg,
1709                             offsetof(struct kib_msg,
1710                                      ibm_u.immediate.ibim_payload),
1711                             payload_niov, payload_kiov,
1712                             payload_offset, payload_nob);
1713
1714         nob = offsetof(struct kib_immediate_msg, ibim_payload[payload_nob]);
1715         kiblnd_init_tx_msg(ni, tx, IBLND_MSG_IMMEDIATE, nob);
1716
1717         tx->tx_lntmsg[0] = lntmsg;              /* finalise lntmsg on completion */
1718         kiblnd_launch_tx(ni, tx, target.nid);
1719         return 0;
1720 }
1721
1722 static void
1723 kiblnd_reply(struct lnet_ni *ni, struct kib_rx *rx, struct lnet_msg *lntmsg)
1724 {
1725         struct lnet_process_id target = lntmsg->msg_target;
1726         unsigned int niov = lntmsg->msg_niov;
1727         struct bio_vec *kiov = lntmsg->msg_kiov;
1728         unsigned int offset = lntmsg->msg_offset;
1729         unsigned int nob = lntmsg->msg_len;
1730         struct kib_tx *tx;
1731         int rc;
1732
1733         tx = kiblnd_get_idle_tx(ni, rx->rx_conn->ibc_peer->ibp_nid);
1734         if (tx == NULL) {
1735                 CERROR("Can't get tx for REPLY to %s\n",
1736                        libcfs_nid2str(target.nid));
1737                 goto failed_0;
1738         }
1739
1740         if (nob == 0)
1741                 rc = 0;
1742         else
1743                 rc = kiblnd_setup_rd_kiov(ni, tx, tx->tx_rd,
1744                                           niov, kiov, offset, nob);
1745
1746         if (rc != 0) {
1747                 CERROR("Can't setup GET src for %s: %d\n",
1748                        libcfs_nid2str(target.nid), rc);
1749                 goto failed_1;
1750         }
1751
1752         rc = kiblnd_init_rdma(rx->rx_conn, tx,
1753                               IBLND_MSG_GET_DONE, nob,
1754                               &rx->rx_msg->ibm_u.get.ibgm_rd,
1755                               rx->rx_msg->ibm_u.get.ibgm_cookie);
1756         if (rc < 0) {
1757                 CERROR("Can't setup rdma for GET from %s: %d\n",
1758                        libcfs_nid2str(target.nid), rc);
1759                 goto failed_1;
1760         }
1761
1762         if (nob == 0) {
1763                 /* No RDMA: local completion may happen now! */
1764                 lnet_finalize(lntmsg, 0);
1765         } else {
1766                 /* RDMA: lnet_finalize(lntmsg) when it
1767                  * completes */
1768                 tx->tx_lntmsg[0] = lntmsg;
1769         }
1770
1771         kiblnd_queue_tx(tx, rx->rx_conn);
1772         return;
1773
1774
1775 failed_1:
1776         tx->tx_hstatus = LNET_MSG_STATUS_LOCAL_ERROR;
1777         kiblnd_tx_done(tx);
1778 failed_0:
1779         lnet_finalize(lntmsg, -EIO);
1780 }
1781
1782 int
1783 kiblnd_recv(struct lnet_ni *ni, void *private, struct lnet_msg *lntmsg,
1784             int delayed, unsigned int niov, struct bio_vec *kiov,
1785             unsigned int offset, unsigned int mlen, unsigned int rlen)
1786 {
1787         struct kib_rx *rx = private;
1788         struct kib_msg *rxmsg = rx->rx_msg;
1789         struct kib_conn *conn = rx->rx_conn;
1790         struct kib_tx *tx;
1791         __u64        ibprm_cookie;
1792         int          nob;
1793         int          post_credit = IBLND_POSTRX_PEER_CREDIT;
1794         int          rc = 0;
1795
1796         LASSERT (mlen <= rlen);
1797         LASSERT (!in_interrupt());
1798
1799         switch (rxmsg->ibm_type) {
1800         default:
1801                 LBUG();
1802
1803         case IBLND_MSG_IMMEDIATE:
1804                 nob = offsetof(struct kib_msg, ibm_u.immediate.ibim_payload[rlen]);
1805                 if (nob > rx->rx_nob) {
1806                         CERROR ("Immediate message from %s too big: %d(%d)\n",
1807                                 libcfs_nid2str(rxmsg->ibm_u.immediate.ibim_hdr.src_nid),
1808                                 nob, rx->rx_nob);
1809                         rc = -EPROTO;
1810                         break;
1811                 }
1812
1813                 lnet_copy_flat2kiov(niov, kiov, offset,
1814                                     IBLND_MSG_SIZE, rxmsg,
1815                                     offsetof(struct kib_msg,
1816                                              ibm_u.immediate.ibim_payload),
1817                                     mlen);
1818                 lnet_finalize(lntmsg, 0);
1819                 break;
1820
1821         case IBLND_MSG_PUT_REQ: {
1822                 struct kib_msg  *txmsg;
1823                 struct kib_rdma_desc *rd;
1824                 ibprm_cookie = rxmsg->ibm_u.putreq.ibprm_cookie;
1825
1826                 if (mlen == 0) {
1827                         lnet_finalize(lntmsg, 0);
1828                         kiblnd_send_completion(rx->rx_conn, IBLND_MSG_PUT_NAK,
1829                                                0, ibprm_cookie);
1830                         break;
1831                 }
1832
1833                 tx = kiblnd_get_idle_tx(ni, conn->ibc_peer->ibp_nid);
1834                 if (tx == NULL) {
1835                         CERROR("Can't allocate tx for %s\n",
1836                                libcfs_nid2str(conn->ibc_peer->ibp_nid));
1837                         /* Not replying will break the connection */
1838                         rc = -ENOMEM;
1839                         break;
1840                 }
1841
1842                 txmsg = tx->tx_msg;
1843                 rd = &txmsg->ibm_u.putack.ibpam_rd;
1844                 rc = kiblnd_setup_rd_kiov(ni, tx, rd,
1845                                           niov, kiov, offset, mlen);
1846                 if (rc != 0) {
1847                         CERROR("Can't setup PUT sink for %s: %d\n",
1848                                libcfs_nid2str(conn->ibc_peer->ibp_nid), rc);
1849                         tx->tx_hstatus = LNET_MSG_STATUS_LOCAL_ERROR;
1850                         kiblnd_tx_done(tx);
1851                         /* tell peer_ni it's over */
1852                         kiblnd_send_completion(rx->rx_conn, IBLND_MSG_PUT_NAK,
1853                                                rc, ibprm_cookie);
1854                         break;
1855                 }
1856
1857                 nob = offsetof(struct kib_putack_msg, ibpam_rd.rd_frags[rd->rd_nfrags]);
1858                 txmsg->ibm_u.putack.ibpam_src_cookie = ibprm_cookie;
1859                 txmsg->ibm_u.putack.ibpam_dst_cookie = tx->tx_cookie;
1860
1861                 kiblnd_init_tx_msg(ni, tx, IBLND_MSG_PUT_ACK, nob);
1862
1863                 tx->tx_lntmsg[0] = lntmsg;      /* finalise lntmsg on completion */
1864                 tx->tx_waiting = 1;             /* waiting for PUT_DONE */
1865                 kiblnd_queue_tx(tx, conn);
1866
1867                 /* reposted buffer reserved for PUT_DONE */
1868                 post_credit = IBLND_POSTRX_NO_CREDIT;
1869                 break;
1870                 }
1871
1872         case IBLND_MSG_GET_REQ:
1873                 if (lntmsg != NULL) {
1874                         /* Optimized GET; RDMA lntmsg's payload */
1875                         kiblnd_reply(ni, rx, lntmsg);
1876                 } else {
1877                         /* GET didn't match anything */
1878                         kiblnd_send_completion(rx->rx_conn, IBLND_MSG_GET_DONE,
1879                                                -ENODATA,
1880                                                rxmsg->ibm_u.get.ibgm_cookie);
1881                 }
1882                 break;
1883         }
1884
1885         kiblnd_post_rx(rx, post_credit);
1886         return rc;
1887 }
1888
1889 int
1890 kiblnd_thread_start(int (*fn)(void *arg), void *arg, char *name)
1891 {
1892         struct task_struct *task = kthread_run(fn, arg, name);
1893
1894         if (IS_ERR(task))
1895                 return PTR_ERR(task);
1896
1897         atomic_inc(&kiblnd_data.kib_nthreads);
1898         return 0;
1899 }
1900
1901 static void
1902 kiblnd_thread_fini (void)
1903 {
1904         atomic_dec (&kiblnd_data.kib_nthreads);
1905 }
1906
1907 static void
1908 kiblnd_peer_alive(struct kib_peer_ni *peer_ni)
1909 {
1910         /* This is racy, but everyone's only writing ktime_get_seconds() */
1911         peer_ni->ibp_last_alive = ktime_get_seconds();
1912         smp_mb();
1913 }
1914
1915 static void
1916 kiblnd_peer_notify(struct kib_peer_ni *peer_ni)
1917 {
1918         int           error = 0;
1919         time64_t last_alive = 0;
1920         unsigned long flags;
1921
1922         read_lock_irqsave(&kiblnd_data.kib_global_lock, flags);
1923
1924         if (kiblnd_peer_idle(peer_ni) && peer_ni->ibp_error != 0) {
1925                 error = peer_ni->ibp_error;
1926                 peer_ni->ibp_error = 0;
1927
1928                 last_alive = peer_ni->ibp_last_alive;
1929         }
1930
1931         read_unlock_irqrestore(&kiblnd_data.kib_global_lock, flags);
1932
1933         if (error != 0)
1934                 lnet_notify(peer_ni->ibp_ni,
1935                             peer_ni->ibp_nid, false, false, last_alive);
1936 }
1937
1938 void
1939 kiblnd_close_conn_locked(struct kib_conn *conn, int error)
1940 {
1941         /* This just does the immediate housekeeping.  'error' is zero for a
1942          * normal shutdown which can happen only after the connection has been
1943          * established.  If the connection is established, schedule the
1944          * connection to be finished off by the connd.  Otherwise the connd is
1945          * already dealing with it (either to set it up or tear it down).
1946          * Caller holds kib_global_lock exclusively in irq context */
1947         struct kib_peer_ni *peer_ni = conn->ibc_peer;
1948         struct kib_dev *dev;
1949         unsigned long flags;
1950
1951         LASSERT (error != 0 || conn->ibc_state >= IBLND_CONN_ESTABLISHED);
1952
1953         if (error != 0 && conn->ibc_comms_error == 0)
1954                 conn->ibc_comms_error = error;
1955
1956         if (conn->ibc_state != IBLND_CONN_ESTABLISHED)
1957                 return; /* already being handled  */
1958
1959         if (error == 0 &&
1960             list_empty(&conn->ibc_tx_noops) &&
1961             list_empty(&conn->ibc_tx_queue) &&
1962             list_empty(&conn->ibc_tx_queue_rsrvd) &&
1963             list_empty(&conn->ibc_tx_queue_nocred) &&
1964             list_empty(&conn->ibc_active_txs)) {
1965                 CDEBUG(D_NET, "closing conn to %s\n", 
1966                        libcfs_nid2str(peer_ni->ibp_nid));
1967         } else {
1968                 CNETERR("Closing conn to %s: error %d%s%s%s%s%s\n",
1969                        libcfs_nid2str(peer_ni->ibp_nid), error,
1970                        list_empty(&conn->ibc_tx_queue) ? "" : "(sending)",
1971                        list_empty(&conn->ibc_tx_noops) ? "" : "(sending_noops)",
1972                        list_empty(&conn->ibc_tx_queue_rsrvd) ?
1973                                                 "" : "(sending_rsrvd)",
1974                        list_empty(&conn->ibc_tx_queue_nocred) ?
1975                                                  "" : "(sending_nocred)",
1976                        list_empty(&conn->ibc_active_txs) ? "" : "(waiting)");
1977         }
1978
1979         dev = ((struct kib_net *)peer_ni->ibp_ni->ni_data)->ibn_dev;
1980         if (peer_ni->ibp_next_conn == conn)
1981                 /* clear next_conn so it won't be used */
1982                 peer_ni->ibp_next_conn = NULL;
1983         list_del(&conn->ibc_list);
1984         /* connd (see below) takes over ibc_list's ref */
1985
1986         if (list_empty(&peer_ni->ibp_conns) &&    /* no more conns */
1987             kiblnd_peer_active(peer_ni)) {         /* still in peer_ni table */
1988                 kiblnd_unlink_peer_locked(peer_ni);
1989
1990                 /* set/clear error on last conn */
1991                 peer_ni->ibp_error = conn->ibc_comms_error;
1992         }
1993
1994         kiblnd_set_conn_state(conn, IBLND_CONN_CLOSING);
1995
1996         if (error != 0 &&
1997             kiblnd_dev_can_failover(dev)) {
1998                 list_add_tail(&dev->ibd_fail_list,
1999                               &kiblnd_data.kib_failed_devs);
2000                 wake_up(&kiblnd_data.kib_failover_waitq);
2001         }
2002
2003         spin_lock_irqsave(&kiblnd_data.kib_connd_lock, flags);
2004
2005         list_add_tail(&conn->ibc_list, &kiblnd_data.kib_connd_conns);
2006         wake_up(&kiblnd_data.kib_connd_waitq);
2007
2008         spin_unlock_irqrestore(&kiblnd_data.kib_connd_lock, flags);
2009 }
2010
2011 void
2012 kiblnd_close_conn(struct kib_conn *conn, int error)
2013 {
2014         unsigned long flags;
2015
2016         write_lock_irqsave(&kiblnd_data.kib_global_lock, flags);
2017
2018         kiblnd_close_conn_locked(conn, error);
2019
2020         write_unlock_irqrestore(&kiblnd_data.kib_global_lock, flags);
2021 }
2022
2023 static void
2024 kiblnd_handle_early_rxs(struct kib_conn *conn)
2025 {
2026         unsigned long flags;
2027         struct kib_rx *rx;
2028
2029         LASSERT(!in_interrupt());
2030         LASSERT(conn->ibc_state >= IBLND_CONN_ESTABLISHED);
2031
2032         write_lock_irqsave(&kiblnd_data.kib_global_lock, flags);
2033         while (!list_empty(&conn->ibc_early_rxs)) {
2034                 rx = list_entry(conn->ibc_early_rxs.next,
2035                                 struct kib_rx, rx_list);
2036                 list_del(&rx->rx_list);
2037                 write_unlock_irqrestore(&kiblnd_data.kib_global_lock, flags);
2038
2039                 kiblnd_handle_rx(rx);
2040
2041                 write_lock_irqsave(&kiblnd_data.kib_global_lock, flags);
2042         }
2043         write_unlock_irqrestore(&kiblnd_data.kib_global_lock, flags);
2044 }
2045
2046 void
2047 kiblnd_abort_txs(struct kib_conn *conn, struct list_head *txs)
2048 {
2049         LIST_HEAD(zombies);
2050         struct kib_tx *nxt;
2051         struct kib_tx *tx;
2052
2053         spin_lock(&conn->ibc_lock);
2054
2055         list_for_each_entry_safe(tx, nxt, txs, tx_list) {
2056                 if (txs == &conn->ibc_active_txs) {
2057                         LASSERT(!tx->tx_queued);
2058                         LASSERT(tx->tx_waiting ||
2059                                 tx->tx_sending != 0);
2060                         if (conn->ibc_comms_error == -ETIMEDOUT) {
2061                                 if (tx->tx_waiting && !tx->tx_sending)
2062                                         tx->tx_hstatus =
2063                                           LNET_MSG_STATUS_REMOTE_TIMEOUT;
2064                                 else if (tx->tx_sending)
2065                                         tx->tx_hstatus =
2066                                           LNET_MSG_STATUS_NETWORK_TIMEOUT;
2067                         }
2068                 } else {
2069                         LASSERT(tx->tx_queued);
2070                         if (conn->ibc_comms_error == -ETIMEDOUT)
2071                                 tx->tx_hstatus = LNET_MSG_STATUS_LOCAL_TIMEOUT;
2072                         else
2073                                 tx->tx_hstatus = LNET_MSG_STATUS_LOCAL_ERROR;
2074                 }
2075
2076                 tx->tx_status = -ECONNABORTED;
2077                 tx->tx_waiting = 0;
2078
2079                 /*
2080                  * TODO: This makes an assumption that
2081                  * kiblnd_tx_complete() will be called for each tx. If
2082                  * that event is dropped we could end up with stale
2083                  * connections floating around. We'd like to deal with
2084                  * that in a better way.
2085                  *
2086                  * Also that means we can exceed the timeout by many
2087                  * seconds.
2088                  */
2089                 if (tx->tx_sending == 0) {
2090                         tx->tx_queued = 0;
2091                         list_move(&tx->tx_list, &zombies);
2092                 }
2093         }
2094
2095         spin_unlock(&conn->ibc_lock);
2096
2097         /*
2098          * aborting transmits occurs when finalizing the connection.
2099          * The connection is finalized on error.
2100          * Passing LNET_MSG_STATUS_OK to txlist_done() will not
2101          * override the value already set in tx->tx_hstatus above.
2102          */
2103         kiblnd_txlist_done(&zombies, -ECONNABORTED, LNET_MSG_STATUS_OK);
2104 }
2105
2106 static void
2107 kiblnd_finalise_conn(struct kib_conn *conn)
2108 {
2109         LASSERT (!in_interrupt());
2110         LASSERT (conn->ibc_state > IBLND_CONN_INIT);
2111
2112         /* abort_receives moves QP state to IB_QPS_ERR.  This is only required
2113          * for connections that didn't get as far as being connected, because
2114          * rdma_disconnect() does this for free. */
2115         kiblnd_abort_receives(conn);
2116
2117         kiblnd_set_conn_state(conn, IBLND_CONN_DISCONNECTED);
2118
2119         /* Complete all tx descs not waiting for sends to complete.
2120          * NB we should be safe from RDMA now that the QP has changed state */
2121
2122         kiblnd_abort_txs(conn, &conn->ibc_tx_noops);
2123         kiblnd_abort_txs(conn, &conn->ibc_tx_queue);
2124         kiblnd_abort_txs(conn, &conn->ibc_tx_queue_rsrvd);
2125         kiblnd_abort_txs(conn, &conn->ibc_tx_queue_nocred);
2126         kiblnd_abort_txs(conn, &conn->ibc_active_txs);
2127
2128         kiblnd_handle_early_rxs(conn);
2129 }
2130
2131 static void
2132 kiblnd_peer_connect_failed(struct kib_peer_ni *peer_ni, int active,
2133                            int error)
2134 {
2135         LIST_HEAD(zombies);
2136         unsigned long   flags;
2137
2138         LASSERT (error != 0);
2139         LASSERT (!in_interrupt());
2140
2141         write_lock_irqsave(&kiblnd_data.kib_global_lock, flags);
2142
2143         if (active) {
2144                 LASSERT(peer_ni->ibp_connecting > 0);
2145                 peer_ni->ibp_connecting--;
2146         } else {
2147                 LASSERT (peer_ni->ibp_accepting > 0);
2148                 peer_ni->ibp_accepting--;
2149         }
2150
2151         if (kiblnd_peer_connecting(peer_ni)) {
2152                 /* another connection attempt under way... */
2153                 write_unlock_irqrestore(&kiblnd_data.kib_global_lock,
2154                                         flags);
2155                 return;
2156         }
2157
2158         peer_ni->ibp_reconnected = 0;
2159         if (list_empty(&peer_ni->ibp_conns)) {
2160                 /* Take peer_ni's blocked transmits to complete with error */
2161                 list_splice_init(&peer_ni->ibp_tx_queue, &zombies);
2162
2163                 if (kiblnd_peer_active(peer_ni))
2164                         kiblnd_unlink_peer_locked(peer_ni);
2165
2166                 peer_ni->ibp_error = error;
2167         } else {
2168                 /* Can't have blocked transmits if there are connections */
2169                 LASSERT(list_empty(&peer_ni->ibp_tx_queue));
2170         }
2171
2172         write_unlock_irqrestore(&kiblnd_data.kib_global_lock, flags);
2173
2174         kiblnd_peer_notify(peer_ni);
2175
2176         if (list_empty(&zombies))
2177                 return;
2178
2179         CNETERR("Deleting messages for %s: connection failed\n",
2180                 libcfs_nid2str(peer_ni->ibp_nid));
2181
2182         kiblnd_txlist_done(&zombies, error,
2183                            LNET_MSG_STATUS_LOCAL_DROPPED);
2184 }
2185
2186 static void
2187 kiblnd_connreq_done(struct kib_conn *conn, int status)
2188 {
2189         struct kib_peer_ni *peer_ni = conn->ibc_peer;
2190         struct kib_tx *tx;
2191         LIST_HEAD(txs);
2192         unsigned long    flags;
2193         int              active;
2194
2195         active = (conn->ibc_state == IBLND_CONN_ACTIVE_CONNECT);
2196
2197         CDEBUG(D_NET,"%s: active(%d), version(%x), status(%d)\n",
2198                libcfs_nid2str(peer_ni->ibp_nid), active,
2199                conn->ibc_version, status);
2200
2201         LASSERT (!in_interrupt());
2202         LASSERT ((conn->ibc_state == IBLND_CONN_ACTIVE_CONNECT &&
2203                   peer_ni->ibp_connecting > 0) ||
2204                  (conn->ibc_state == IBLND_CONN_PASSIVE_WAIT &&
2205                   peer_ni->ibp_accepting > 0));
2206
2207         LIBCFS_FREE(conn->ibc_connvars, sizeof(*conn->ibc_connvars));
2208         conn->ibc_connvars = NULL;
2209
2210         if (status != 0) {
2211                 /* failed to establish connection */
2212                 kiblnd_peer_connect_failed(peer_ni, active, status);
2213                 kiblnd_finalise_conn(conn);
2214                 return;
2215         }
2216
2217         /* connection established */
2218         write_lock_irqsave(&kiblnd_data.kib_global_lock, flags);
2219
2220         conn->ibc_last_send = ktime_get();
2221         kiblnd_set_conn_state(conn, IBLND_CONN_ESTABLISHED);
2222         kiblnd_peer_alive(peer_ni);
2223
2224         /* Add conn to peer_ni's list and nuke any dangling conns from a different
2225          * peer_ni instance... */
2226         kiblnd_conn_addref(conn);       /* +1 ref for ibc_list */
2227         list_add(&conn->ibc_list, &peer_ni->ibp_conns);
2228         peer_ni->ibp_reconnected = 0;
2229         if (active)
2230                 peer_ni->ibp_connecting--;
2231         else
2232                 peer_ni->ibp_accepting--;
2233
2234         if (peer_ni->ibp_version == 0) {
2235                 peer_ni->ibp_version     = conn->ibc_version;
2236                 peer_ni->ibp_incarnation = conn->ibc_incarnation;
2237         }
2238
2239         if (peer_ni->ibp_version     != conn->ibc_version ||
2240             peer_ni->ibp_incarnation != conn->ibc_incarnation) {
2241                 kiblnd_close_stale_conns_locked(peer_ni, conn->ibc_version,
2242                                                 conn->ibc_incarnation);
2243                 peer_ni->ibp_version     = conn->ibc_version;
2244                 peer_ni->ibp_incarnation = conn->ibc_incarnation;
2245         }
2246
2247         /* grab pending txs while I have the lock */
2248         list_splice_init(&peer_ni->ibp_tx_queue, &txs);
2249
2250         if (!kiblnd_peer_active(peer_ni) ||        /* peer_ni has been deleted */
2251             conn->ibc_comms_error != 0) {       /* error has happened already */
2252
2253                 /* start to shut down connection */
2254                 kiblnd_close_conn_locked(conn, -ECONNABORTED);
2255                 write_unlock_irqrestore(&kiblnd_data.kib_global_lock, flags);
2256
2257                 kiblnd_txlist_done(&txs, -ECONNABORTED,
2258                                    LNET_MSG_STATUS_LOCAL_ERROR);
2259
2260                 return;
2261         }
2262
2263         /* +1 ref for myself, this connection is visible to other threads
2264          * now, refcount of peer:ibp_conns can be released by connection
2265          * close from either a different thread, or the calling of
2266          * kiblnd_check_sends_locked() below. See bz21911 for details.
2267          */
2268         kiblnd_conn_addref(conn);
2269         write_unlock_irqrestore(&kiblnd_data.kib_global_lock, flags);
2270
2271         /* Schedule blocked txs
2272          * Note: if we are running with conns_per_peer > 1, these blocked
2273          * txs will all get scheduled to the first connection which gets
2274          * scheduled.  We won't be using round robin on this first batch.
2275          */
2276         spin_lock(&conn->ibc_lock);
2277         while (!list_empty(&txs)) {
2278                 tx = list_entry(txs.next, struct kib_tx, tx_list);
2279                 list_del(&tx->tx_list);
2280
2281                 kiblnd_queue_tx_locked(tx, conn);
2282         }
2283         kiblnd_check_sends_locked(conn);
2284         spin_unlock(&conn->ibc_lock);
2285
2286         /* schedule blocked rxs */
2287         kiblnd_handle_early_rxs(conn);
2288         kiblnd_conn_decref(conn);
2289 }
2290
2291 static void
2292 kiblnd_reject(struct rdma_cm_id *cmid, struct kib_rej *rej)
2293 {
2294         int          rc;
2295
2296         rc = rdma_reject(cmid, rej, sizeof(*rej));
2297
2298         if (rc != 0)
2299                 CWARN("Error %d sending reject\n", rc);
2300 }
2301
2302 static int
2303 kiblnd_passive_connect(struct rdma_cm_id *cmid, void *priv, int priv_nob)
2304 {
2305         rwlock_t                *g_lock = &kiblnd_data.kib_global_lock;
2306         struct kib_msg *reqmsg = priv;
2307         struct kib_msg *ackmsg;
2308         struct kib_dev *ibdev;
2309         struct kib_peer_ni *peer_ni;
2310         struct kib_peer_ni *peer2;
2311         struct kib_conn *conn;
2312         struct lnet_ni *ni = NULL;
2313         struct kib_net *net = NULL;
2314         lnet_nid_t             nid;
2315         struct rdma_conn_param cp;
2316         struct kib_rej rej;
2317         int                    version = IBLND_MSG_VERSION;
2318         unsigned long          flags;
2319         int                    rc;
2320         struct sockaddr_in    *peer_addr;
2321         LASSERT (!in_interrupt());
2322
2323         /* cmid inherits 'context' from the corresponding listener id */
2324         ibdev = cmid->context;
2325         LASSERT(ibdev);
2326
2327         memset(&rej, 0, sizeof(rej));
2328         rej.ibr_magic                = IBLND_MSG_MAGIC;
2329         rej.ibr_why                  = IBLND_REJECT_FATAL;
2330         rej.ibr_cp.ibcp_max_msg_size = IBLND_MSG_SIZE;
2331
2332         peer_addr = (struct sockaddr_in *)&(cmid->route.addr.dst_addr);
2333         if (*kiblnd_tunables.kib_require_priv_port &&
2334             ntohs(peer_addr->sin_port) >= PROT_SOCK) {
2335                 __u32 ip = ntohl(peer_addr->sin_addr.s_addr);
2336                 CERROR("peer_ni's port (%pI4h:%hu) is not privileged\n",
2337                        &ip, ntohs(peer_addr->sin_port));
2338                 goto failed;
2339         }
2340
2341         if (priv_nob < offsetof(struct kib_msg, ibm_type)) {
2342                 CERROR("Short connection request\n");
2343                 goto failed;
2344         }
2345
2346         /* Future protocol version compatibility support!  If the
2347          * o2iblnd-specific protocol changes, or when LNET unifies
2348          * protocols over all LNDs, the initial connection will
2349          * negotiate a protocol version.  I trap this here to avoid
2350          * console errors; the reject tells the peer_ni which protocol I
2351          * speak. */
2352         if (reqmsg->ibm_magic == LNET_PROTO_MAGIC ||
2353             reqmsg->ibm_magic == __swab32(LNET_PROTO_MAGIC))
2354                 goto failed;
2355         if (reqmsg->ibm_magic == IBLND_MSG_MAGIC &&
2356             reqmsg->ibm_version != IBLND_MSG_VERSION &&
2357             reqmsg->ibm_version != IBLND_MSG_VERSION_1)
2358                 goto failed;
2359         if (reqmsg->ibm_magic == __swab32(IBLND_MSG_MAGIC) &&
2360             reqmsg->ibm_version != __swab16(IBLND_MSG_VERSION) &&
2361             reqmsg->ibm_version != __swab16(IBLND_MSG_VERSION_1))
2362                 goto failed;
2363
2364         rc = kiblnd_unpack_msg(reqmsg, priv_nob);
2365         if (rc != 0) {
2366                 CERROR("Can't parse connection request: %d\n", rc);
2367                 goto failed;
2368         }
2369
2370         nid = reqmsg->ibm_srcnid;
2371         ni  = lnet_nid2ni_addref(reqmsg->ibm_dstnid);
2372
2373         if (ni != NULL) {
2374                 net = (struct kib_net *)ni->ni_data;
2375                 rej.ibr_incarnation = net->ibn_incarnation;
2376         }
2377
2378         if (ni == NULL ||                         /* no matching net */
2379             ni->ni_nid != reqmsg->ibm_dstnid ||   /* right NET, wrong NID! */
2380             net->ibn_dev != ibdev) {              /* wrong device */
2381                 CERROR("Can't accept conn from %s on %s (%s:%d:%pI4h): "
2382                        "bad dst nid %s\n", libcfs_nid2str(nid),
2383                        ni == NULL ? "NA" : libcfs_nid2str(ni->ni_nid),
2384                        ibdev->ibd_ifname, ibdev->ibd_nnets,
2385                         &ibdev->ibd_ifip,
2386                        libcfs_nid2str(reqmsg->ibm_dstnid));
2387
2388                 goto failed;
2389         }
2390
2391        /* check time stamp as soon as possible */
2392         if (reqmsg->ibm_dststamp != 0 &&
2393             reqmsg->ibm_dststamp != net->ibn_incarnation) {
2394                 CWARN("Stale connection request\n");
2395                 rej.ibr_why = IBLND_REJECT_CONN_STALE;
2396                 goto failed;
2397         }
2398
2399         /* I can accept peer_ni's version */
2400         version = reqmsg->ibm_version;
2401
2402         if (reqmsg->ibm_type != IBLND_MSG_CONNREQ) {
2403                 CERROR("Unexpected connreq msg type: %x from %s\n",
2404                        reqmsg->ibm_type, libcfs_nid2str(nid));
2405                 goto failed;
2406         }
2407
2408         if (reqmsg->ibm_u.connparams.ibcp_queue_depth >
2409             kiblnd_msg_queue_size(version, ni)) {
2410                 CERROR("Can't accept conn from %s, queue depth too large: "
2411                        " %d (<=%d wanted)\n",
2412                        libcfs_nid2str(nid),
2413                        reqmsg->ibm_u.connparams.ibcp_queue_depth,
2414                        kiblnd_msg_queue_size(version, ni));
2415
2416                 if (version == IBLND_MSG_VERSION)
2417                         rej.ibr_why = IBLND_REJECT_MSG_QUEUE_SIZE;
2418
2419                 goto failed;
2420         }
2421
2422         if (reqmsg->ibm_u.connparams.ibcp_max_frags >
2423             IBLND_MAX_RDMA_FRAGS) {
2424                 CWARN("Can't accept conn from %s (version %x): "
2425                       "max_frags %d too large (%d wanted)\n",
2426                       libcfs_nid2str(nid), version,
2427                       reqmsg->ibm_u.connparams.ibcp_max_frags,
2428                       IBLND_MAX_RDMA_FRAGS);
2429
2430                 if (version >= IBLND_MSG_VERSION)
2431                         rej.ibr_why = IBLND_REJECT_RDMA_FRAGS;
2432
2433                 goto failed;
2434         } else if (reqmsg->ibm_u.connparams.ibcp_max_frags <
2435                    IBLND_MAX_RDMA_FRAGS &&
2436                    net->ibn_fmr_ps == NULL) {
2437                 CWARN("Can't accept conn from %s (version %x): "
2438                       "max_frags %d incompatible without FMR pool "
2439                       "(%d wanted)\n",
2440                       libcfs_nid2str(nid), version,
2441                       reqmsg->ibm_u.connparams.ibcp_max_frags,
2442                       IBLND_MAX_RDMA_FRAGS);
2443
2444                 if (version == IBLND_MSG_VERSION)
2445                         rej.ibr_why = IBLND_REJECT_RDMA_FRAGS;
2446
2447                 goto failed;
2448         }
2449
2450         if (reqmsg->ibm_u.connparams.ibcp_max_msg_size > IBLND_MSG_SIZE) {
2451                 CERROR("Can't accept %s: message size %d too big (%d max)\n",
2452                        libcfs_nid2str(nid),
2453                        reqmsg->ibm_u.connparams.ibcp_max_msg_size,
2454                        IBLND_MSG_SIZE);
2455                 goto failed;
2456         }
2457
2458         /* assume 'nid' is a new peer_ni; create  */
2459         rc = kiblnd_create_peer(ni, &peer_ni, nid);
2460         if (rc != 0) {
2461                 CERROR("Can't create peer_ni for %s\n", libcfs_nid2str(nid));
2462                 rej.ibr_why = IBLND_REJECT_NO_RESOURCES;
2463                 goto failed;
2464         }
2465
2466         /* We have validated the peer's parameters so use those */
2467         peer_ni->ibp_max_frags = reqmsg->ibm_u.connparams.ibcp_max_frags;
2468         peer_ni->ibp_queue_depth = reqmsg->ibm_u.connparams.ibcp_queue_depth;
2469
2470         write_lock_irqsave(g_lock, flags);
2471
2472         peer2 = kiblnd_find_peer_locked(ni, nid);
2473         if (peer2 != NULL) {
2474                 if (peer2->ibp_version == 0) {
2475                         peer2->ibp_version     = version;
2476                         peer2->ibp_incarnation = reqmsg->ibm_srcstamp;
2477                 }
2478
2479                 /* not the guy I've talked with */
2480                 if (peer2->ibp_incarnation != reqmsg->ibm_srcstamp ||
2481                     peer2->ibp_version     != version) {
2482                         kiblnd_close_peer_conns_locked(peer2, -ESTALE);
2483
2484                         if (kiblnd_peer_active(peer2)) {
2485                                 peer2->ibp_incarnation = reqmsg->ibm_srcstamp;
2486                                 peer2->ibp_version = version;
2487                         }
2488                         write_unlock_irqrestore(g_lock, flags);
2489
2490                         CWARN("Conn stale %s version %x/%x incarnation %llu/%llu\n",
2491                               libcfs_nid2str(nid), peer2->ibp_version, version,
2492                               peer2->ibp_incarnation, reqmsg->ibm_srcstamp);
2493
2494                         kiblnd_peer_decref(peer_ni);
2495                         rej.ibr_why = IBLND_REJECT_CONN_STALE;
2496                         goto failed;
2497                 }
2498
2499                 /* Tie-break connection race in favour of the higher NID.
2500                  * If we keep running into a race condition multiple times,
2501                  * we have to assume that the connection attempt with the
2502                  * higher NID is stuck in a connecting state and will never
2503                  * recover.  As such, we pass through this if-block and let
2504                  * the lower NID connection win so we can move forward.
2505                  */
2506                 if (peer2->ibp_connecting != 0 &&
2507                     nid < ni->ni_nid && peer2->ibp_races <
2508                     MAX_CONN_RACES_BEFORE_ABORT) {
2509                         peer2->ibp_races++;
2510                         write_unlock_irqrestore(g_lock, flags);
2511
2512                         CDEBUG(D_NET, "Conn race %s\n",
2513                                libcfs_nid2str(peer2->ibp_nid));
2514
2515                         kiblnd_peer_decref(peer_ni);
2516                         rej.ibr_why = IBLND_REJECT_CONN_RACE;
2517                         goto failed;
2518                 }
2519                 if (peer2->ibp_races >= MAX_CONN_RACES_BEFORE_ABORT)
2520                         CNETERR("Conn race %s: unresolved after %d attempts, letting lower NID win\n",
2521                                 libcfs_nid2str(peer2->ibp_nid),
2522                                 MAX_CONN_RACES_BEFORE_ABORT);
2523                 /*
2524                  * passive connection is allowed even this peer_ni is waiting for
2525                  * reconnection.
2526                  */
2527                 peer2->ibp_reconnecting = 0;
2528                 peer2->ibp_races = 0;
2529                 peer2->ibp_accepting++;
2530                 kiblnd_peer_addref(peer2);
2531
2532                 /* Race with kiblnd_launch_tx (active connect) to create peer_ni
2533                  * so copy validated parameters since we now know what the
2534                  * peer_ni's limits are */
2535                 peer2->ibp_max_frags = peer_ni->ibp_max_frags;
2536                 peer2->ibp_queue_depth = peer_ni->ibp_queue_depth;
2537
2538                 write_unlock_irqrestore(g_lock, flags);
2539                 kiblnd_peer_decref(peer_ni);
2540                 peer_ni = peer2;
2541         } else {
2542                 /* Brand new peer_ni */
2543                 LASSERT (peer_ni->ibp_accepting == 0);
2544                 LASSERT (peer_ni->ibp_version == 0 &&
2545                          peer_ni->ibp_incarnation == 0);
2546
2547                 peer_ni->ibp_accepting   = 1;
2548                 peer_ni->ibp_version     = version;
2549                 peer_ni->ibp_incarnation = reqmsg->ibm_srcstamp;
2550
2551                 /* I have a ref on ni that prevents it being shutdown */
2552                 LASSERT (net->ibn_shutdown == 0);
2553
2554                 kiblnd_peer_addref(peer_ni);
2555                 list_add_tail(&peer_ni->ibp_list, kiblnd_nid2peerlist(nid));
2556
2557                 write_unlock_irqrestore(g_lock, flags);
2558         }
2559
2560         conn = kiblnd_create_conn(peer_ni, cmid, IBLND_CONN_PASSIVE_WAIT, version);
2561         if (conn == NULL) {
2562                 kiblnd_peer_connect_failed(peer_ni, 0, -ENOMEM);
2563                 kiblnd_peer_decref(peer_ni);
2564                 rej.ibr_why = IBLND_REJECT_NO_RESOURCES;
2565                 goto failed;
2566         }
2567
2568         /* conn now "owns" cmid, so I return success from here on to ensure the
2569          * CM callback doesn't destroy cmid. */
2570         conn->ibc_incarnation      = reqmsg->ibm_srcstamp;
2571         conn->ibc_credits          = conn->ibc_queue_depth;
2572         conn->ibc_reserved_credits = conn->ibc_queue_depth;
2573         LASSERT(conn->ibc_credits + conn->ibc_reserved_credits +
2574                 IBLND_OOB_MSGS(version) <= IBLND_RX_MSGS(conn));
2575
2576         ackmsg = &conn->ibc_connvars->cv_msg;
2577         memset(ackmsg, 0, sizeof(*ackmsg));
2578
2579         kiblnd_init_msg(ackmsg, IBLND_MSG_CONNACK,
2580                         sizeof(ackmsg->ibm_u.connparams));
2581         ackmsg->ibm_u.connparams.ibcp_queue_depth  = conn->ibc_queue_depth;
2582         ackmsg->ibm_u.connparams.ibcp_max_frags    = conn->ibc_max_frags;
2583         ackmsg->ibm_u.connparams.ibcp_max_msg_size = IBLND_MSG_SIZE;
2584
2585         kiblnd_pack_msg(ni, ackmsg, version, 0, nid, reqmsg->ibm_srcstamp);
2586
2587         memset(&cp, 0, sizeof(cp));
2588         cp.private_data        = ackmsg;
2589         cp.private_data_len    = ackmsg->ibm_nob;
2590         cp.responder_resources = 0;             /* No atomic ops or RDMA reads */
2591         cp.initiator_depth     = 0;
2592         cp.flow_control        = 1;
2593         cp.retry_count         = *kiblnd_tunables.kib_retry_count;
2594         cp.rnr_retry_count     = *kiblnd_tunables.kib_rnr_retry_count;
2595
2596         CDEBUG(D_NET, "Accept %s\n", libcfs_nid2str(nid));
2597
2598         rc = rdma_accept(cmid, &cp);
2599         if (rc != 0) {
2600                 CERROR("Can't accept %s: %d\n", libcfs_nid2str(nid), rc);
2601                 rej.ibr_version = version;
2602                 rej.ibr_why     = IBLND_REJECT_FATAL;
2603
2604                 kiblnd_reject(cmid, &rej);
2605                 kiblnd_connreq_done(conn, rc);
2606                 kiblnd_conn_decref(conn);
2607         }
2608
2609         lnet_ni_decref(ni);
2610         return 0;
2611
2612  failed:
2613         if (ni != NULL) {
2614                 rej.ibr_cp.ibcp_queue_depth =
2615                         kiblnd_msg_queue_size(version, ni);
2616                 rej.ibr_cp.ibcp_max_frags   = IBLND_MAX_RDMA_FRAGS;
2617                 lnet_ni_decref(ni);
2618         }
2619
2620         rej.ibr_version = version;
2621         kiblnd_reject(cmid, &rej);
2622
2623         return -ECONNREFUSED;
2624 }
2625
2626 static void
2627 kiblnd_check_reconnect(struct kib_conn *conn, int version,
2628                        u64 incarnation, int why, struct kib_connparams *cp)
2629 {
2630         rwlock_t        *glock = &kiblnd_data.kib_global_lock;
2631         struct kib_peer_ni *peer_ni = conn->ibc_peer;
2632         char            *reason;
2633         int              msg_size = IBLND_MSG_SIZE;
2634         int              frag_num = -1;
2635         int              queue_dep = -1;
2636         bool             reconnect;
2637         unsigned long    flags;
2638
2639         LASSERT(conn->ibc_state == IBLND_CONN_ACTIVE_CONNECT);
2640         LASSERT(peer_ni->ibp_connecting > 0);   /* 'conn' at least */
2641
2642         if (cp) {
2643                 msg_size        = cp->ibcp_max_msg_size;
2644                 frag_num        = cp->ibcp_max_frags;
2645                 queue_dep       = cp->ibcp_queue_depth;
2646         }
2647
2648         write_lock_irqsave(glock, flags);
2649         /* retry connection if it's still needed and no other connection
2650          * attempts (active or passive) are in progress
2651          * NB: reconnect is still needed even when ibp_tx_queue is
2652          * empty if ibp_version != version because reconnect may be
2653          * initiated.
2654          */
2655         reconnect = (!list_empty(&peer_ni->ibp_tx_queue) ||
2656                      peer_ni->ibp_version != version) &&
2657                     peer_ni->ibp_connecting &&
2658                     peer_ni->ibp_accepting == 0;
2659         if (!reconnect) {
2660                 reason = "no need";
2661                 goto out;
2662         }
2663
2664         switch (why) {
2665         default:
2666                 reason = "Unknown";
2667                 break;
2668
2669         case IBLND_REJECT_RDMA_FRAGS: {
2670                 struct lnet_ioctl_config_o2iblnd_tunables *tunables;
2671
2672                 if (!cp) {
2673                         reason = "can't negotiate max frags";
2674                         goto out;
2675                 }
2676                 tunables = &peer_ni->ibp_ni->ni_lnd_tunables.lnd_tun_u.lnd_o2ib;
2677 #ifdef HAVE_IB_GET_DMA_MR
2678                 /*
2679                  * This check only makes sense if the kernel supports global
2680                  * memory registration. Otherwise, map_on_demand will never == 0
2681                  */
2682                 if (!tunables->lnd_map_on_demand) {
2683                         reason = "map_on_demand must be enabled";
2684                         goto out;
2685                 }
2686 #endif
2687                 if (conn->ibc_max_frags <= frag_num) {
2688                         reason = "unsupported max frags";
2689                         goto out;
2690                 }
2691
2692                 peer_ni->ibp_max_frags = frag_num;
2693                 reason = "rdma fragments";
2694                 break;
2695         }
2696         case IBLND_REJECT_MSG_QUEUE_SIZE:
2697                 if (!cp) {
2698                         reason = "can't negotiate queue depth";
2699                         goto out;
2700                 }
2701                 if (conn->ibc_queue_depth <= queue_dep) {
2702                         reason = "unsupported queue depth";
2703                         goto out;
2704                 }
2705
2706                 peer_ni->ibp_queue_depth = queue_dep;
2707                 reason = "queue depth";
2708                 break;
2709
2710         case IBLND_REJECT_CONN_STALE:
2711                 reason = "stale";
2712                 break;
2713
2714         case IBLND_REJECT_CONN_RACE:
2715                 reason = "conn race";
2716                 break;
2717
2718         case IBLND_REJECT_CONN_UNCOMPAT:
2719                 reason = "version negotiation";
2720                 break;
2721
2722         case IBLND_REJECT_INVALID_SRV_ID:
2723                 reason = "invalid service id";
2724                 break;
2725         }
2726
2727         conn->ibc_reconnect = 1;
2728         peer_ni->ibp_reconnecting++;
2729         peer_ni->ibp_version = version;
2730         if (incarnation != 0)
2731                 peer_ni->ibp_incarnation = incarnation;
2732  out:
2733         write_unlock_irqrestore(&kiblnd_data.kib_global_lock, flags);
2734
2735         CNETERR("%s: %s (%s), %x, %x, msg_size: %d, queue_depth: %d/%d, max_frags: %d/%d\n",
2736                 libcfs_nid2str(peer_ni->ibp_nid),
2737                 reconnect ? "reconnect" : "don't reconnect",
2738                 reason, IBLND_MSG_VERSION, version, msg_size,
2739                 conn->ibc_queue_depth, queue_dep,
2740                 conn->ibc_max_frags, frag_num);
2741         /*
2742          * if conn::ibc_reconnect is TRUE, connd will reconnect to the peer_ni
2743          * while destroying the zombie
2744          */
2745 }
2746
2747 static void
2748 kiblnd_rejected(struct kib_conn *conn, int reason, void *priv, int priv_nob)
2749 {
2750         struct kib_peer_ni *peer_ni = conn->ibc_peer;
2751
2752         LASSERT (!in_interrupt());
2753         LASSERT (conn->ibc_state == IBLND_CONN_ACTIVE_CONNECT);
2754
2755         switch (reason) {
2756         case IB_CM_REJ_STALE_CONN:
2757                 kiblnd_check_reconnect(conn, IBLND_MSG_VERSION, 0,
2758                                        IBLND_REJECT_CONN_STALE, NULL);
2759                 break;
2760
2761         case IB_CM_REJ_INVALID_SERVICE_ID:
2762                 kiblnd_check_reconnect(conn, IBLND_MSG_VERSION, 0,
2763                                        IBLND_REJECT_INVALID_SRV_ID, NULL);
2764                 CNETERR("%s rejected: no listener at %d\n",
2765                         libcfs_nid2str(peer_ni->ibp_nid),
2766                         *kiblnd_tunables.kib_service);
2767                 break;
2768
2769         case IB_CM_REJ_CONSUMER_DEFINED:
2770                 if (priv_nob >= offsetof(struct kib_rej, ibr_padding)) {
2771                         struct kib_rej *rej = priv;
2772                         struct kib_connparams *cp = NULL;
2773                         int               flip        = 0;
2774                         __u64             incarnation = -1;
2775
2776                         /* NB. default incarnation is -1 because:
2777                          * a) V1 will ignore dst incarnation in connreq.
2778                          * b) V2 will provide incarnation while rejecting me,
2779                          *    -1 will be overwrote.
2780                          *
2781                          * if I try to connect to a V1 peer_ni with V2 protocol,
2782                          * it rejected me then upgrade to V2, I have no idea
2783                          * about the upgrading and try to reconnect with V1,
2784                          * in this case upgraded V2 can find out I'm trying to
2785                          * talk to the old guy and reject me(incarnation is -1). 
2786                          */
2787
2788                         if (rej->ibr_magic == __swab32(IBLND_MSG_MAGIC) ||
2789                             rej->ibr_magic == __swab32(LNET_PROTO_MAGIC)) {
2790                                 __swab32s(&rej->ibr_magic);
2791                                 __swab16s(&rej->ibr_version);
2792                                 flip = 1;
2793                         }
2794
2795                         if (priv_nob >= sizeof(struct kib_rej) &&
2796                             rej->ibr_version > IBLND_MSG_VERSION_1) {
2797                                 /* priv_nob is always 148 in current version
2798                                  * of OFED, so we still need to check version.
2799                                  * (define of IB_CM_REJ_PRIVATE_DATA_SIZE) */
2800                                 cp = &rej->ibr_cp;
2801
2802                                 if (flip) {
2803                                         __swab64s(&rej->ibr_incarnation);
2804                                         __swab16s(&cp->ibcp_queue_depth);
2805                                         __swab16s(&cp->ibcp_max_frags);
2806                                         __swab32s(&cp->ibcp_max_msg_size);
2807                                 }
2808
2809                                 incarnation = rej->ibr_incarnation;
2810                         }
2811
2812                         if (rej->ibr_magic != IBLND_MSG_MAGIC &&
2813                             rej->ibr_magic != LNET_PROTO_MAGIC) {
2814                                 CERROR("%s rejected: consumer defined fatal error\n",
2815                                        libcfs_nid2str(peer_ni->ibp_nid));
2816                                 break;
2817                         }
2818
2819                         if (rej->ibr_version != IBLND_MSG_VERSION &&
2820                             rej->ibr_version != IBLND_MSG_VERSION_1) {
2821                                 CERROR("%s rejected: o2iblnd version %x error\n",
2822                                        libcfs_nid2str(peer_ni->ibp_nid),
2823                                        rej->ibr_version);
2824                                 break;
2825                         }
2826
2827                         if (rej->ibr_why     == IBLND_REJECT_FATAL &&
2828                             rej->ibr_version == IBLND_MSG_VERSION_1) {
2829                                 CDEBUG(D_NET, "rejected by old version peer_ni %s: %x\n",
2830                                        libcfs_nid2str(peer_ni->ibp_nid), rej->ibr_version);
2831
2832                                 if (conn->ibc_version != IBLND_MSG_VERSION_1)
2833                                         rej->ibr_why = IBLND_REJECT_CONN_UNCOMPAT;
2834                         }
2835
2836                         switch (rej->ibr_why) {
2837                         case IBLND_REJECT_CONN_RACE:
2838                         case IBLND_REJECT_CONN_STALE:
2839                         case IBLND_REJECT_CONN_UNCOMPAT:
2840                         case IBLND_REJECT_MSG_QUEUE_SIZE:
2841                         case IBLND_REJECT_RDMA_FRAGS:
2842                                 kiblnd_check_reconnect(conn, rej->ibr_version,
2843                                                 incarnation, rej->ibr_why, cp);
2844                                 break;
2845
2846                         case IBLND_REJECT_NO_RESOURCES:
2847                                 CERROR("%s rejected: o2iblnd no resources\n",
2848                                        libcfs_nid2str(peer_ni->ibp_nid));
2849                                 break;
2850
2851                         case IBLND_REJECT_FATAL:
2852                                 CERROR("%s rejected: o2iblnd fatal error\n",
2853                                        libcfs_nid2str(peer_ni->ibp_nid));
2854                                 break;
2855
2856                         default:
2857                                 CERROR("%s rejected: o2iblnd reason %d\n",
2858                                        libcfs_nid2str(peer_ni->ibp_nid),
2859                                        rej->ibr_why);
2860                                 break;
2861                         }
2862                         break;
2863                 }
2864                 /* fall through */
2865         default:
2866                 CNETERR("%s rejected: reason %d, size %d\n",
2867                         libcfs_nid2str(peer_ni->ibp_nid), reason, priv_nob);
2868                 break;
2869         }
2870
2871         kiblnd_connreq_done(conn, -ECONNREFUSED);
2872 }
2873
2874 static void
2875 kiblnd_check_connreply(struct kib_conn *conn, void *priv, int priv_nob)
2876 {
2877         struct kib_peer_ni *peer_ni = conn->ibc_peer;
2878         struct lnet_ni *ni = peer_ni->ibp_ni;
2879         struct kib_net *net = ni->ni_data;
2880         struct kib_msg *msg = priv;
2881         int            ver  = conn->ibc_version;
2882         int            rc   = kiblnd_unpack_msg(msg, priv_nob);
2883         unsigned long  flags;
2884
2885         LASSERT (net != NULL);
2886
2887         if (rc != 0) {
2888                 CERROR("Can't unpack connack from %s: %d\n",
2889                        libcfs_nid2str(peer_ni->ibp_nid), rc);
2890                 goto failed;
2891         }
2892
2893         if (msg->ibm_type != IBLND_MSG_CONNACK) {
2894                 CERROR("Unexpected message %d from %s\n",
2895                        msg->ibm_type, libcfs_nid2str(peer_ni->ibp_nid));
2896                 rc = -EPROTO;
2897                 goto failed;
2898         }
2899
2900         if (ver != msg->ibm_version) {
2901                 CERROR("%s replied version %x is different with "
2902                        "requested version %x\n",
2903                        libcfs_nid2str(peer_ni->ibp_nid), msg->ibm_version, ver);
2904                 rc = -EPROTO;
2905                 goto failed;
2906         }
2907
2908         if (msg->ibm_u.connparams.ibcp_queue_depth >
2909             conn->ibc_queue_depth) {
2910                 CERROR("%s has incompatible queue depth %d (<=%d wanted)\n",
2911                        libcfs_nid2str(peer_ni->ibp_nid),
2912                        msg->ibm_u.connparams.ibcp_queue_depth,
2913                        conn->ibc_queue_depth);
2914                 rc = -EPROTO;
2915                 goto failed;
2916         }
2917
2918         if (msg->ibm_u.connparams.ibcp_max_frags >
2919             conn->ibc_max_frags) {
2920                 CERROR("%s has incompatible max_frags %d (<=%d wanted)\n",
2921                        libcfs_nid2str(peer_ni->ibp_nid),
2922                        msg->ibm_u.connparams.ibcp_max_frags,
2923                        conn->ibc_max_frags);
2924                 rc = -EPROTO;
2925                 goto failed;
2926         }
2927
2928         if (msg->ibm_u.connparams.ibcp_max_msg_size > IBLND_MSG_SIZE) {
2929                 CERROR("%s max message size %d too big (%d max)\n",
2930                        libcfs_nid2str(peer_ni->ibp_nid),
2931                        msg->ibm_u.connparams.ibcp_max_msg_size,
2932                        IBLND_MSG_SIZE);
2933                 rc = -EPROTO;
2934                 goto failed;
2935         }
2936
2937         read_lock_irqsave(&kiblnd_data.kib_global_lock, flags);
2938         if (msg->ibm_dstnid == ni->ni_nid &&
2939             msg->ibm_dststamp == net->ibn_incarnation)
2940                 rc = 0;
2941         else
2942                 rc = -ESTALE;
2943         read_unlock_irqrestore(&kiblnd_data.kib_global_lock, flags);
2944
2945         if (rc != 0) {
2946                 CERROR("Bad connection reply from %s, rc = %d, "
2947                        "version: %x max_frags: %d\n",
2948                        libcfs_nid2str(peer_ni->ibp_nid), rc,
2949                        msg->ibm_version, msg->ibm_u.connparams.ibcp_max_frags);
2950                 goto failed;
2951         }
2952
2953         conn->ibc_incarnation      = msg->ibm_srcstamp;
2954         conn->ibc_credits          = msg->ibm_u.connparams.ibcp_queue_depth;
2955         conn->ibc_reserved_credits = msg->ibm_u.connparams.ibcp_queue_depth;
2956         conn->ibc_queue_depth      = msg->ibm_u.connparams.ibcp_queue_depth;
2957         conn->ibc_max_frags        = msg->ibm_u.connparams.ibcp_max_frags;
2958         LASSERT(conn->ibc_credits + conn->ibc_reserved_credits +
2959                 IBLND_OOB_MSGS(ver) <= IBLND_RX_MSGS(conn));
2960
2961         kiblnd_connreq_done(conn, 0);
2962         return;
2963
2964  failed:
2965         /* NB My QP has already established itself, so I handle anything going
2966          * wrong here by setting ibc_comms_error.
2967          * kiblnd_connreq_done(0) moves the conn state to ESTABLISHED, but then
2968          * immediately tears it down. */
2969
2970         LASSERT (rc != 0);
2971         conn->ibc_comms_error = rc;
2972         kiblnd_connreq_done(conn, 0);
2973 }
2974
2975 static int
2976 kiblnd_active_connect(struct rdma_cm_id *cmid)
2977 {
2978         struct kib_peer_ni *peer_ni = cmid->context;
2979         struct kib_conn *conn;
2980         struct kib_msg *msg;
2981         struct rdma_conn_param cp;
2982         int                      version;
2983         __u64                    incarnation;
2984         unsigned long            flags;
2985         int                      rc;
2986
2987         read_lock_irqsave(&kiblnd_data.kib_global_lock, flags);
2988
2989         incarnation = peer_ni->ibp_incarnation;
2990         version     = (peer_ni->ibp_version == 0) ? IBLND_MSG_VERSION :
2991                                                  peer_ni->ibp_version;
2992
2993         read_unlock_irqrestore(&kiblnd_data.kib_global_lock, flags);
2994
2995         conn = kiblnd_create_conn(peer_ni, cmid, IBLND_CONN_ACTIVE_CONNECT,
2996                                   version);
2997         if (conn == NULL) {
2998                 kiblnd_peer_connect_failed(peer_ni, 1, -ENOMEM);
2999                 kiblnd_peer_decref(peer_ni); /* lose cmid's ref */
3000                 return -ENOMEM;
3001         }
3002
3003         /* conn "owns" cmid now, so I return success from here on to ensure the
3004          * CM callback doesn't destroy cmid. conn also takes over cmid's ref
3005          * on peer_ni */
3006
3007         msg = &conn->ibc_connvars->cv_msg;
3008
3009         memset(msg, 0, sizeof(*msg));
3010         kiblnd_init_msg(msg, IBLND_MSG_CONNREQ, sizeof(msg->ibm_u.connparams));
3011         msg->ibm_u.connparams.ibcp_queue_depth  = conn->ibc_queue_depth;
3012         msg->ibm_u.connparams.ibcp_max_frags    = conn->ibc_max_frags;
3013         msg->ibm_u.connparams.ibcp_max_msg_size = IBLND_MSG_SIZE;
3014
3015         kiblnd_pack_msg(peer_ni->ibp_ni, msg, version,
3016                         0, peer_ni->ibp_nid, incarnation);
3017
3018         memset(&cp, 0, sizeof(cp));
3019         cp.private_data        = msg;
3020         cp.private_data_len    = msg->ibm_nob;
3021         cp.responder_resources = 0;             /* No atomic ops or RDMA reads */
3022         cp.initiator_depth     = 0;
3023         cp.flow_control        = 1;
3024         cp.retry_count         = *kiblnd_tunables.kib_retry_count;
3025         cp.rnr_retry_count     = *kiblnd_tunables.kib_rnr_retry_count;
3026
3027         LASSERT(cmid->context == (void *)conn);
3028         LASSERT(conn->ibc_cmid == cmid);
3029
3030         rc = rdma_connect(cmid, &cp);
3031         if (rc != 0) {
3032                 CERROR("Can't connect to %s: %d\n",
3033                        libcfs_nid2str(peer_ni->ibp_nid), rc);
3034                 kiblnd_connreq_done(conn, rc);
3035                 kiblnd_conn_decref(conn);
3036         }
3037
3038         return 0;
3039 }
3040
3041 int
3042 kiblnd_cm_callback(struct rdma_cm_id *cmid, struct rdma_cm_event *event)
3043 {
3044         struct kib_peer_ni *peer_ni;
3045         struct kib_conn *conn;
3046         int rc;
3047
3048         switch (event->event) {
3049         default:
3050                 CERROR("Unexpected event: %d, status: %d\n",
3051                        event->event, event->status);
3052                 LBUG();
3053
3054         case RDMA_CM_EVENT_CONNECT_REQUEST:
3055                 /* destroy cmid on failure */
3056                 rc = kiblnd_passive_connect(cmid,
3057                                             (void *)KIBLND_CONN_PARAM(event),
3058                                             KIBLND_CONN_PARAM_LEN(event));
3059                 CDEBUG(D_NET, "connreq: %d\n", rc);
3060                 return rc;
3061
3062         case RDMA_CM_EVENT_ADDR_ERROR:
3063                 peer_ni = cmid->context;
3064                 CNETERR("%s: ADDR ERROR %d\n",
3065                        libcfs_nid2str(peer_ni->ibp_nid), event->status);
3066                 kiblnd_peer_connect_failed(peer_ni, 1, -EHOSTUNREACH);
3067                 kiblnd_peer_decref(peer_ni);
3068                 return -EHOSTUNREACH;      /* rc != 0 destroys cmid */
3069
3070         case RDMA_CM_EVENT_ADDR_RESOLVED:
3071                 peer_ni = cmid->context;
3072
3073                 CDEBUG(D_NET,"%s Addr resolved: %d\n",
3074                        libcfs_nid2str(peer_ni->ibp_nid), event->status);
3075
3076                 if (event->status != 0) {
3077                         CNETERR("Can't resolve address for %s: %d\n",
3078                                 libcfs_nid2str(peer_ni->ibp_nid), event->status);
3079                         rc = event->status;
3080                 } else {
3081                         rc = rdma_resolve_route(
3082                                 cmid, kiblnd_timeout() * 1000);
3083                         if (rc == 0) {
3084                                 struct kib_net *net = peer_ni->ibp_ni->ni_data;
3085                                 struct kib_dev *dev = net->ibn_dev;
3086
3087                                 CDEBUG(D_NET, "%s: connection bound to "\
3088                                        "%s:%pI4h:%s\n",
3089                                        libcfs_nid2str(peer_ni->ibp_nid),
3090                                        dev->ibd_ifname,
3091                                        &dev->ibd_ifip, cmid->device->name);
3092
3093                                 return 0;
3094                         }
3095
3096                         /* Can't initiate route resolution */
3097                         CERROR("Can't resolve route for %s: %d\n",
3098                                libcfs_nid2str(peer_ni->ibp_nid), rc);
3099                 }