Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6
[linux-2.6] / net / rds / ib_cm.c
1 /*
2  * Copyright (c) 2006 Oracle.  All rights reserved.
3  *
4  * This software is available to you under a choice of one of two
5  * licenses.  You may choose to be licensed under the terms of the GNU
6  * General Public License (GPL) Version 2, available from the file
7  * COPYING in the main directory of this source tree, or the
8  * OpenIB.org BSD license below:
9  *
10  *     Redistribution and use in source and binary forms, with or
11  *     without modification, are permitted provided that the following
12  *     conditions are met:
13  *
14  *      - Redistributions of source code must retain the above
15  *        copyright notice, this list of conditions and the following
16  *        disclaimer.
17  *
18  *      - Redistributions in binary form must reproduce the above
19  *        copyright notice, this list of conditions and the following
20  *        disclaimer in the documentation and/or other materials
21  *        provided with the distribution.
22  *
23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30  * SOFTWARE.
31  *
32  */
33 #include <linux/kernel.h>
34 #include <linux/in.h>
35 #include <linux/vmalloc.h>
36
37 #include "rds.h"
38 #include "ib.h"
39
40 /*
41  * Set the selected protocol version
42  */
43 static void rds_ib_set_protocol(struct rds_connection *conn, unsigned int version)
44 {
45         conn->c_version = version;
46 }
47
48 /*
49  * Set up flow control
50  */
51 static void rds_ib_set_flow_control(struct rds_connection *conn, u32 credits)
52 {
53         struct rds_ib_connection *ic = conn->c_transport_data;
54
55         if (rds_ib_sysctl_flow_control && credits != 0) {
56                 /* We're doing flow control */
57                 ic->i_flowctl = 1;
58                 rds_ib_send_add_credits(conn, credits);
59         } else {
60                 ic->i_flowctl = 0;
61         }
62 }
63
64 /*
65  * Tune RNR behavior. Without flow control, we use a rather
66  * low timeout, but not the absolute minimum - this should
67  * be tunable.
68  *
69  * We already set the RNR retry count to 7 (which is the
70  * smallest infinite number :-) above.
71  * If flow control is off, we want to change this back to 0
72  * so that we learn quickly when our credit accounting is
73  * buggy.
74  *
75  * Caller passes in a qp_attr pointer - don't waste stack spacv
76  * by allocation this twice.
77  */
78 static void
79 rds_ib_tune_rnr(struct rds_ib_connection *ic, struct ib_qp_attr *attr)
80 {
81         int ret;
82
83         attr->min_rnr_timer = IB_RNR_TIMER_000_32;
84         ret = ib_modify_qp(ic->i_cm_id->qp, attr, IB_QP_MIN_RNR_TIMER);
85         if (ret)
86                 printk(KERN_NOTICE "ib_modify_qp(IB_QP_MIN_RNR_TIMER): err=%d\n", -ret);
87 }
88
89 /*
90  * Connection established.
91  * We get here for both outgoing and incoming connection.
92  */
93 void rds_ib_cm_connect_complete(struct rds_connection *conn, struct rdma_cm_event *event)
94 {
95         const struct rds_ib_connect_private *dp = NULL;
96         struct rds_ib_connection *ic = conn->c_transport_data;
97         struct rds_ib_device *rds_ibdev;
98         struct ib_qp_attr qp_attr;
99         int err;
100
101         if (event->param.conn.private_data_len) {
102                 dp = event->param.conn.private_data;
103
104                 rds_ib_set_protocol(conn,
105                                 RDS_PROTOCOL(dp->dp_protocol_major,
106                                         dp->dp_protocol_minor));
107                 rds_ib_set_flow_control(conn, be32_to_cpu(dp->dp_credit));
108         }
109
110         printk(KERN_NOTICE "RDS/IB: connected to %pI4 version %u.%u%s\n",
111                         &conn->c_laddr,
112                         RDS_PROTOCOL_MAJOR(conn->c_version),
113                         RDS_PROTOCOL_MINOR(conn->c_version),
114                         ic->i_flowctl ? ", flow control" : "");
115
116         /* Tune RNR behavior */
117         rds_ib_tune_rnr(ic, &qp_attr);
118
119         qp_attr.qp_state = IB_QPS_RTS;
120         err = ib_modify_qp(ic->i_cm_id->qp, &qp_attr, IB_QP_STATE);
121         if (err)
122                 printk(KERN_NOTICE "ib_modify_qp(IB_QP_STATE, RTS): err=%d\n", err);
123
124         /* update ib_device with this local ipaddr & conn */
125         rds_ibdev = ib_get_client_data(ic->i_cm_id->device, &rds_ib_client);
126         err = rds_ib_update_ipaddr(rds_ibdev, conn->c_laddr);
127         if (err)
128                 printk(KERN_ERR "rds_ib_update_ipaddr failed (%d)\n", err);
129         err = rds_ib_add_conn(rds_ibdev, conn);
130         if (err)
131                 printk(KERN_ERR "rds_ib_add_conn failed (%d)\n", err);
132
133         /* If the peer gave us the last packet it saw, process this as if
134          * we had received a regular ACK. */
135         if (dp && dp->dp_ack_seq)
136                 rds_send_drop_acked(conn, be64_to_cpu(dp->dp_ack_seq), NULL);
137
138         rds_connect_complete(conn);
139 }
140
141 static void rds_ib_cm_fill_conn_param(struct rds_connection *conn,
142                         struct rdma_conn_param *conn_param,
143                         struct rds_ib_connect_private *dp,
144                         u32 protocol_version)
145 {
146         memset(conn_param, 0, sizeof(struct rdma_conn_param));
147         /* XXX tune these? */
148         conn_param->responder_resources = 1;
149         conn_param->initiator_depth = 1;
150         conn_param->retry_count = 7;
151         conn_param->rnr_retry_count = 7;
152
153         if (dp) {
154                 struct rds_ib_connection *ic = conn->c_transport_data;
155
156                 memset(dp, 0, sizeof(*dp));
157                 dp->dp_saddr = conn->c_laddr;
158                 dp->dp_daddr = conn->c_faddr;
159                 dp->dp_protocol_major = RDS_PROTOCOL_MAJOR(protocol_version);
160                 dp->dp_protocol_minor = RDS_PROTOCOL_MINOR(protocol_version);
161                 dp->dp_protocol_minor_mask = cpu_to_be16(RDS_IB_SUPPORTED_PROTOCOLS);
162                 dp->dp_ack_seq = rds_ib_piggyb_ack(ic);
163
164                 /* Advertise flow control */
165                 if (ic->i_flowctl) {
166                         unsigned int credits;
167
168                         credits = IB_GET_POST_CREDITS(atomic_read(&ic->i_credits));
169                         dp->dp_credit = cpu_to_be32(credits);
170                         atomic_sub(IB_SET_POST_CREDITS(credits), &ic->i_credits);
171                 }
172
173                 conn_param->private_data = dp;
174                 conn_param->private_data_len = sizeof(*dp);
175         }
176 }
177
178 static void rds_ib_cq_event_handler(struct ib_event *event, void *data)
179 {
180         rdsdebug("event %u data %p\n", event->event, data);
181 }
182
183 static void rds_ib_qp_event_handler(struct ib_event *event, void *data)
184 {
185         struct rds_connection *conn = data;
186         struct rds_ib_connection *ic = conn->c_transport_data;
187
188         rdsdebug("conn %p ic %p event %u\n", conn, ic, event->event);
189
190         switch (event->event) {
191         case IB_EVENT_COMM_EST:
192                 rdma_notify(ic->i_cm_id, IB_EVENT_COMM_EST);
193                 break;
194         default:
195                 printk(KERN_WARNING "RDS/ib: unhandled QP event %u "
196                        "on connection to %pI4\n", event->event,
197                        &conn->c_faddr);
198                 break;
199         }
200 }
201
202 /*
203  * This needs to be very careful to not leave IS_ERR pointers around for
204  * cleanup to trip over.
205  */
206 static int rds_ib_setup_qp(struct rds_connection *conn)
207 {
208         struct rds_ib_connection *ic = conn->c_transport_data;
209         struct ib_device *dev = ic->i_cm_id->device;
210         struct ib_qp_init_attr attr;
211         struct rds_ib_device *rds_ibdev;
212         int ret;
213
214         /* rds_ib_add_one creates a rds_ib_device object per IB device,
215          * and allocates a protection domain, memory range and FMR pool
216          * for each.  If that fails for any reason, it will not register
217          * the rds_ibdev at all.
218          */
219         rds_ibdev = ib_get_client_data(dev, &rds_ib_client);
220         if (rds_ibdev == NULL) {
221                 if (printk_ratelimit())
222                         printk(KERN_NOTICE "RDS/IB: No client_data for device %s\n",
223                                         dev->name);
224                 return -EOPNOTSUPP;
225         }
226
227         if (rds_ibdev->max_wrs < ic->i_send_ring.w_nr + 1)
228                 rds_ib_ring_resize(&ic->i_send_ring, rds_ibdev->max_wrs - 1);
229         if (rds_ibdev->max_wrs < ic->i_recv_ring.w_nr + 1)
230                 rds_ib_ring_resize(&ic->i_recv_ring, rds_ibdev->max_wrs - 1);
231
232         /* Protection domain and memory range */
233         ic->i_pd = rds_ibdev->pd;
234         ic->i_mr = rds_ibdev->mr;
235
236         ic->i_send_cq = ib_create_cq(dev, rds_ib_send_cq_comp_handler,
237                                      rds_ib_cq_event_handler, conn,
238                                      ic->i_send_ring.w_nr + 1, 0);
239         if (IS_ERR(ic->i_send_cq)) {
240                 ret = PTR_ERR(ic->i_send_cq);
241                 ic->i_send_cq = NULL;
242                 rdsdebug("ib_create_cq send failed: %d\n", ret);
243                 goto out;
244         }
245
246         ic->i_recv_cq = ib_create_cq(dev, rds_ib_recv_cq_comp_handler,
247                                      rds_ib_cq_event_handler, conn,
248                                      ic->i_recv_ring.w_nr, 0);
249         if (IS_ERR(ic->i_recv_cq)) {
250                 ret = PTR_ERR(ic->i_recv_cq);
251                 ic->i_recv_cq = NULL;
252                 rdsdebug("ib_create_cq recv failed: %d\n", ret);
253                 goto out;
254         }
255
256         ret = ib_req_notify_cq(ic->i_send_cq, IB_CQ_NEXT_COMP);
257         if (ret) {
258                 rdsdebug("ib_req_notify_cq send failed: %d\n", ret);
259                 goto out;
260         }
261
262         ret = ib_req_notify_cq(ic->i_recv_cq, IB_CQ_SOLICITED);
263         if (ret) {
264                 rdsdebug("ib_req_notify_cq recv failed: %d\n", ret);
265                 goto out;
266         }
267
268         /* XXX negotiate max send/recv with remote? */
269         memset(&attr, 0, sizeof(attr));
270         attr.event_handler = rds_ib_qp_event_handler;
271         attr.qp_context = conn;
272         /* + 1 to allow for the single ack message */
273         attr.cap.max_send_wr = ic->i_send_ring.w_nr + 1;
274         attr.cap.max_recv_wr = ic->i_recv_ring.w_nr + 1;
275         attr.cap.max_send_sge = rds_ibdev->max_sge;
276         attr.cap.max_recv_sge = RDS_IB_RECV_SGE;
277         attr.sq_sig_type = IB_SIGNAL_REQ_WR;
278         attr.qp_type = IB_QPT_RC;
279         attr.send_cq = ic->i_send_cq;
280         attr.recv_cq = ic->i_recv_cq;
281
282         /*
283          * XXX this can fail if max_*_wr is too large?  Are we supposed
284          * to back off until we get a value that the hardware can support?
285          */
286         ret = rdma_create_qp(ic->i_cm_id, ic->i_pd, &attr);
287         if (ret) {
288                 rdsdebug("rdma_create_qp failed: %d\n", ret);
289                 goto out;
290         }
291
292         ic->i_send_hdrs = ib_dma_alloc_coherent(dev,
293                                            ic->i_send_ring.w_nr *
294                                                 sizeof(struct rds_header),
295                                            &ic->i_send_hdrs_dma, GFP_KERNEL);
296         if (ic->i_send_hdrs == NULL) {
297                 ret = -ENOMEM;
298                 rdsdebug("ib_dma_alloc_coherent send failed\n");
299                 goto out;
300         }
301
302         ic->i_recv_hdrs = ib_dma_alloc_coherent(dev,
303                                            ic->i_recv_ring.w_nr *
304                                                 sizeof(struct rds_header),
305                                            &ic->i_recv_hdrs_dma, GFP_KERNEL);
306         if (ic->i_recv_hdrs == NULL) {
307                 ret = -ENOMEM;
308                 rdsdebug("ib_dma_alloc_coherent recv failed\n");
309                 goto out;
310         }
311
312         ic->i_ack = ib_dma_alloc_coherent(dev, sizeof(struct rds_header),
313                                        &ic->i_ack_dma, GFP_KERNEL);
314         if (ic->i_ack == NULL) {
315                 ret = -ENOMEM;
316                 rdsdebug("ib_dma_alloc_coherent ack failed\n");
317                 goto out;
318         }
319
320         ic->i_sends = vmalloc(ic->i_send_ring.w_nr * sizeof(struct rds_ib_send_work));
321         if (ic->i_sends == NULL) {
322                 ret = -ENOMEM;
323                 rdsdebug("send allocation failed\n");
324                 goto out;
325         }
326         rds_ib_send_init_ring(ic);
327
328         ic->i_recvs = vmalloc(ic->i_recv_ring.w_nr * sizeof(struct rds_ib_recv_work));
329         if (ic->i_recvs == NULL) {
330                 ret = -ENOMEM;
331                 rdsdebug("recv allocation failed\n");
332                 goto out;
333         }
334
335         rds_ib_recv_init_ring(ic);
336         rds_ib_recv_init_ack(ic);
337
338         /* Post receive buffers - as a side effect, this will update
339          * the posted credit count. */
340         rds_ib_recv_refill(conn, GFP_KERNEL, GFP_HIGHUSER, 1);
341
342         rdsdebug("conn %p pd %p mr %p cq %p %p\n", conn, ic->i_pd, ic->i_mr,
343                  ic->i_send_cq, ic->i_recv_cq);
344
345 out:
346         return ret;
347 }
348
349 static u32 rds_ib_protocol_compatible(const struct rds_ib_connect_private *dp)
350 {
351         u16 common;
352         u32 version = 0;
353
354         /* rdma_cm private data is odd - when there is any private data in the
355          * request, we will be given a pretty large buffer without telling us the
356          * original size. The only way to tell the difference is by looking at
357          * the contents, which are initialized to zero.
358          * If the protocol version fields aren't set, this is a connection attempt
359          * from an older version. This could could be 3.0 or 2.0 - we can't tell.
360          * We really should have changed this for OFED 1.3 :-( */
361         if (dp->dp_protocol_major == 0)
362                 return RDS_PROTOCOL_3_0;
363
364         common = be16_to_cpu(dp->dp_protocol_minor_mask) & RDS_IB_SUPPORTED_PROTOCOLS;
365         if (dp->dp_protocol_major == 3 && common) {
366                 version = RDS_PROTOCOL_3_0;
367                 while ((common >>= 1) != 0)
368                         version++;
369         } else if (printk_ratelimit()) {
370                 printk(KERN_NOTICE "RDS: Connection from %pI4 using "
371                         "incompatible protocol version %u.%u\n",
372                         &dp->dp_saddr,
373                         dp->dp_protocol_major,
374                         dp->dp_protocol_minor);
375         }
376         return version;
377 }
378
379 int rds_ib_cm_handle_connect(struct rdma_cm_id *cm_id,
380                                     struct rdma_cm_event *event)
381 {
382         __be64 lguid = cm_id->route.path_rec->sgid.global.interface_id;
383         __be64 fguid = cm_id->route.path_rec->dgid.global.interface_id;
384         const struct rds_ib_connect_private *dp = event->param.conn.private_data;
385         struct rds_ib_connect_private dp_rep;
386         struct rds_connection *conn = NULL;
387         struct rds_ib_connection *ic = NULL;
388         struct rdma_conn_param conn_param;
389         u32 version;
390         int err, destroy = 1;
391
392         /* Check whether the remote protocol version matches ours. */
393         version = rds_ib_protocol_compatible(dp);
394         if (!version)
395                 goto out;
396
397         rdsdebug("saddr %pI4 daddr %pI4 RDSv%u.%u lguid 0x%llx fguid "
398                  "0x%llx\n", &dp->dp_saddr, &dp->dp_daddr,
399                  RDS_PROTOCOL_MAJOR(version), RDS_PROTOCOL_MINOR(version),
400                  (unsigned long long)be64_to_cpu(lguid),
401                  (unsigned long long)be64_to_cpu(fguid));
402
403         conn = rds_conn_create(dp->dp_daddr, dp->dp_saddr, &rds_ib_transport,
404                                GFP_KERNEL);
405         if (IS_ERR(conn)) {
406                 rdsdebug("rds_conn_create failed (%ld)\n", PTR_ERR(conn));
407                 conn = NULL;
408                 goto out;
409         }
410
411         /*
412          * The connection request may occur while the
413          * previous connection exist, e.g. in case of failover.
414          * But as connections may be initiated simultaneously
415          * by both hosts, we have a random backoff mechanism -
416          * see the comment above rds_queue_reconnect()
417          */
418         mutex_lock(&conn->c_cm_lock);
419         if (!rds_conn_transition(conn, RDS_CONN_DOWN, RDS_CONN_CONNECTING)) {
420                 if (rds_conn_state(conn) == RDS_CONN_UP) {
421                         rdsdebug("incoming connect while connecting\n");
422                         rds_conn_drop(conn);
423                         rds_ib_stats_inc(s_ib_listen_closed_stale);
424                 } else
425                 if (rds_conn_state(conn) == RDS_CONN_CONNECTING) {
426                         /* Wait and see - our connect may still be succeeding */
427                         rds_ib_stats_inc(s_ib_connect_raced);
428                 }
429                 mutex_unlock(&conn->c_cm_lock);
430                 goto out;
431         }
432
433         ic = conn->c_transport_data;
434
435         rds_ib_set_protocol(conn, version);
436         rds_ib_set_flow_control(conn, be32_to_cpu(dp->dp_credit));
437
438         /* If the peer gave us the last packet it saw, process this as if
439          * we had received a regular ACK. */
440         if (dp->dp_ack_seq)
441                 rds_send_drop_acked(conn, be64_to_cpu(dp->dp_ack_seq), NULL);
442
443         BUG_ON(cm_id->context);
444         BUG_ON(ic->i_cm_id);
445
446         ic->i_cm_id = cm_id;
447         cm_id->context = conn;
448
449         /* We got halfway through setting up the ib_connection, if we
450          * fail now, we have to take the long route out of this mess. */
451         destroy = 0;
452
453         err = rds_ib_setup_qp(conn);
454         if (err) {
455                 rds_ib_conn_error(conn, "rds_ib_setup_qp failed (%d)\n", err);
456                 goto out;
457         }
458
459         rds_ib_cm_fill_conn_param(conn, &conn_param, &dp_rep, version);
460
461         /* rdma_accept() calls rdma_reject() internally if it fails */
462         err = rdma_accept(cm_id, &conn_param);
463         mutex_unlock(&conn->c_cm_lock);
464         if (err) {
465                 rds_ib_conn_error(conn, "rdma_accept failed (%d)\n", err);
466                 goto out;
467         }
468
469         return 0;
470
471 out:
472         rdma_reject(cm_id, NULL, 0);
473         return destroy;
474 }
475
476
477 int rds_ib_cm_initiate_connect(struct rdma_cm_id *cm_id)
478 {
479         struct rds_connection *conn = cm_id->context;
480         struct rds_ib_connection *ic = conn->c_transport_data;
481         struct rdma_conn_param conn_param;
482         struct rds_ib_connect_private dp;
483         int ret;
484
485         /* If the peer doesn't do protocol negotiation, we must
486          * default to RDSv3.0 */
487         rds_ib_set_protocol(conn, RDS_PROTOCOL_3_0);
488         ic->i_flowctl = rds_ib_sysctl_flow_control;     /* advertise flow control */
489
490         ret = rds_ib_setup_qp(conn);
491         if (ret) {
492                 rds_ib_conn_error(conn, "rds_ib_setup_qp failed (%d)\n", ret);
493                 goto out;
494         }
495
496         rds_ib_cm_fill_conn_param(conn, &conn_param, &dp, RDS_PROTOCOL_VERSION);
497
498         ret = rdma_connect(cm_id, &conn_param);
499         if (ret)
500                 rds_ib_conn_error(conn, "rdma_connect failed (%d)\n", ret);
501
502 out:
503         /* Beware - returning non-zero tells the rdma_cm to destroy
504          * the cm_id. We should certainly not do it as long as we still
505          * "own" the cm_id. */
506         if (ret) {
507                 if (ic->i_cm_id == cm_id)
508                         ret = 0;
509         }
510         return ret;
511 }
512
513 int rds_ib_conn_connect(struct rds_connection *conn)
514 {
515         struct rds_ib_connection *ic = conn->c_transport_data;
516         struct sockaddr_in src, dest;
517         int ret;
518
519         /* XXX I wonder what affect the port space has */
520         /* delegate cm event handler to rdma_transport */
521         ic->i_cm_id = rdma_create_id(rds_rdma_cm_event_handler, conn,
522                                      RDMA_PS_TCP);
523         if (IS_ERR(ic->i_cm_id)) {
524                 ret = PTR_ERR(ic->i_cm_id);
525                 ic->i_cm_id = NULL;
526                 rdsdebug("rdma_create_id() failed: %d\n", ret);
527                 goto out;
528         }
529
530         rdsdebug("created cm id %p for conn %p\n", ic->i_cm_id, conn);
531
532         src.sin_family = AF_INET;
533         src.sin_addr.s_addr = (__force u32)conn->c_laddr;
534         src.sin_port = (__force u16)htons(0);
535
536         dest.sin_family = AF_INET;
537         dest.sin_addr.s_addr = (__force u32)conn->c_faddr;
538         dest.sin_port = (__force u16)htons(RDS_PORT);
539
540         ret = rdma_resolve_addr(ic->i_cm_id, (struct sockaddr *)&src,
541                                 (struct sockaddr *)&dest,
542                                 RDS_RDMA_RESOLVE_TIMEOUT_MS);
543         if (ret) {
544                 rdsdebug("addr resolve failed for cm id %p: %d\n", ic->i_cm_id,
545                          ret);
546                 rdma_destroy_id(ic->i_cm_id);
547                 ic->i_cm_id = NULL;
548         }
549
550 out:
551         return ret;
552 }
553
554 /*
555  * This is so careful about only cleaning up resources that were built up
556  * so that it can be called at any point during startup.  In fact it
557  * can be called multiple times for a given connection.
558  */
559 void rds_ib_conn_shutdown(struct rds_connection *conn)
560 {
561         struct rds_ib_connection *ic = conn->c_transport_data;
562         int err = 0;
563
564         rdsdebug("cm %p pd %p cq %p %p qp %p\n", ic->i_cm_id,
565                  ic->i_pd, ic->i_send_cq, ic->i_recv_cq,
566                  ic->i_cm_id ? ic->i_cm_id->qp : NULL);
567
568         if (ic->i_cm_id) {
569                 struct ib_device *dev = ic->i_cm_id->device;
570
571                 rdsdebug("disconnecting cm %p\n", ic->i_cm_id);
572                 err = rdma_disconnect(ic->i_cm_id);
573                 if (err) {
574                         /* Actually this may happen quite frequently, when
575                          * an outgoing connect raced with an incoming connect.
576                          */
577                         rdsdebug("failed to disconnect, cm: %p err %d\n",
578                                 ic->i_cm_id, err);
579                 }
580
581                 wait_event(rds_ib_ring_empty_wait,
582                         rds_ib_ring_empty(&ic->i_send_ring) &&
583                         rds_ib_ring_empty(&ic->i_recv_ring));
584
585                 if (ic->i_send_hdrs)
586                         ib_dma_free_coherent(dev,
587                                            ic->i_send_ring.w_nr *
588                                                 sizeof(struct rds_header),
589                                            ic->i_send_hdrs,
590                                            ic->i_send_hdrs_dma);
591
592                 if (ic->i_recv_hdrs)
593                         ib_dma_free_coherent(dev,
594                                            ic->i_recv_ring.w_nr *
595                                                 sizeof(struct rds_header),
596                                            ic->i_recv_hdrs,
597                                            ic->i_recv_hdrs_dma);
598
599                 if (ic->i_ack)
600                         ib_dma_free_coherent(dev, sizeof(struct rds_header),
601                                              ic->i_ack, ic->i_ack_dma);
602
603                 if (ic->i_sends)
604                         rds_ib_send_clear_ring(ic);
605                 if (ic->i_recvs)
606                         rds_ib_recv_clear_ring(ic);
607
608                 if (ic->i_cm_id->qp)
609                         rdma_destroy_qp(ic->i_cm_id);
610                 if (ic->i_send_cq)
611                         ib_destroy_cq(ic->i_send_cq);
612                 if (ic->i_recv_cq)
613                         ib_destroy_cq(ic->i_recv_cq);
614                 rdma_destroy_id(ic->i_cm_id);
615
616                 /*
617                  * Move connection back to the nodev list.
618                  */
619                 if (ic->rds_ibdev) {
620
621                         spin_lock_irq(&ic->rds_ibdev->spinlock);
622                         BUG_ON(list_empty(&ic->ib_node));
623                         list_del(&ic->ib_node);
624                         spin_unlock_irq(&ic->rds_ibdev->spinlock);
625
626                         spin_lock_irq(&ib_nodev_conns_lock);
627                         list_add_tail(&ic->ib_node, &ib_nodev_conns);
628                         spin_unlock_irq(&ib_nodev_conns_lock);
629                         ic->rds_ibdev = NULL;
630                 }
631
632                 ic->i_cm_id = NULL;
633                 ic->i_pd = NULL;
634                 ic->i_mr = NULL;
635                 ic->i_send_cq = NULL;
636                 ic->i_recv_cq = NULL;
637                 ic->i_send_hdrs = NULL;
638                 ic->i_recv_hdrs = NULL;
639                 ic->i_ack = NULL;
640         }
641         BUG_ON(ic->rds_ibdev);
642
643         /* Clear pending transmit */
644         if (ic->i_rm) {
645                 rds_message_put(ic->i_rm);
646                 ic->i_rm = NULL;
647         }
648
649         /* Clear the ACK state */
650         clear_bit(IB_ACK_IN_FLIGHT, &ic->i_ack_flags);
651         rds_ib_set_64bit(&ic->i_ack_next, 0);
652         ic->i_ack_recv = 0;
653
654         /* Clear flow control state */
655         ic->i_flowctl = 0;
656         atomic_set(&ic->i_credits, 0);
657
658         rds_ib_ring_init(&ic->i_send_ring, rds_ib_sysctl_max_send_wr);
659         rds_ib_ring_init(&ic->i_recv_ring, rds_ib_sysctl_max_recv_wr);
660
661         if (ic->i_ibinc) {
662                 rds_inc_put(&ic->i_ibinc->ii_inc);
663                 ic->i_ibinc = NULL;
664         }
665
666         vfree(ic->i_sends);
667         ic->i_sends = NULL;
668         vfree(ic->i_recvs);
669         ic->i_recvs = NULL;
670 }
671
672 int rds_ib_conn_alloc(struct rds_connection *conn, gfp_t gfp)
673 {
674         struct rds_ib_connection *ic;
675         unsigned long flags;
676
677         /* XXX too lazy? */
678         ic = kzalloc(sizeof(struct rds_ib_connection), GFP_KERNEL);
679         if (ic == NULL)
680                 return -ENOMEM;
681
682         INIT_LIST_HEAD(&ic->ib_node);
683         mutex_init(&ic->i_recv_mutex);
684
685         /*
686          * rds_ib_conn_shutdown() waits for these to be emptied so they
687          * must be initialized before it can be called.
688          */
689         rds_ib_ring_init(&ic->i_send_ring, rds_ib_sysctl_max_send_wr);
690         rds_ib_ring_init(&ic->i_recv_ring, rds_ib_sysctl_max_recv_wr);
691
692         ic->conn = conn;
693         conn->c_transport_data = ic;
694
695         spin_lock_irqsave(&ib_nodev_conns_lock, flags);
696         list_add_tail(&ic->ib_node, &ib_nodev_conns);
697         spin_unlock_irqrestore(&ib_nodev_conns_lock, flags);
698
699
700         rdsdebug("conn %p conn ic %p\n", conn, conn->c_transport_data);
701         return 0;
702 }
703
704 void rds_ib_conn_free(void *arg)
705 {
706         struct rds_ib_connection *ic = arg;
707         rdsdebug("ic %p\n", ic);
708         list_del(&ic->ib_node);
709         kfree(ic);
710 }
711
712
713 /*
714  * An error occurred on the connection
715  */
716 void
717 __rds_ib_conn_error(struct rds_connection *conn, const char *fmt, ...)
718 {
719         va_list ap;
720
721         rds_conn_drop(conn);
722
723         va_start(ap, fmt);
724         vprintk(fmt, ap);
725         va_end(ap);
726 }