394cf6b4d0aad63c4dbb7bb51ecdd4b0b69b2dbc
[linux-2.6.git] / net / rds / iw_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 "iw.h"
39
40 /*
41  * Set the selected protocol version
42  */
43 static void rds_iw_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_iw_set_flow_control(struct rds_connection *conn, u32 credits)
52 {
53         struct rds_iw_connection *ic = conn->c_transport_data;
54
55         if (rds_iw_sysctl_flow_control && credits != 0) {
56                 /* We're doing flow control */
57                 ic->i_flowctl = 1;
58                 rds_iw_send_add_credits(conn, credits);
59         } else {
60                 ic->i_flowctl = 0;
61         }
62 }
63
64 /*
65  * Connection established.
66  * We get here for both outgoing and incoming connection.
67  */
68 void rds_iw_cm_connect_complete(struct rds_connection *conn, struct rdma_cm_event *event)
69 {
70         const struct rds_iw_connect_private *dp = NULL;
71         struct rds_iw_connection *ic = conn->c_transport_data;
72         struct rds_iw_device *rds_iwdev;
73         int err;
74
75         if (event->param.conn.private_data_len) {
76                 dp = event->param.conn.private_data;
77
78                 rds_iw_set_protocol(conn,
79                                 RDS_PROTOCOL(dp->dp_protocol_major,
80                                         dp->dp_protocol_minor));
81                 rds_iw_set_flow_control(conn, be32_to_cpu(dp->dp_credit));
82         }
83
84         /* update ib_device with this local ipaddr & conn */
85         rds_iwdev = ib_get_client_data(ic->i_cm_id->device, &rds_iw_client);
86         err = rds_iw_update_cm_id(rds_iwdev, ic->i_cm_id);
87         if (err)
88                 printk(KERN_ERR "rds_iw_update_ipaddr failed (%d)\n", err);
89         rds_iw_add_conn(rds_iwdev, conn);
90
91         /* If the peer gave us the last packet it saw, process this as if
92          * we had received a regular ACK. */
93         if (dp && dp->dp_ack_seq)
94                 rds_send_drop_acked(conn, be64_to_cpu(dp->dp_ack_seq), NULL);
95
96         printk(KERN_NOTICE "RDS/IW: connected to %pI4<->%pI4 version %u.%u%s\n",
97                         &conn->c_laddr, &conn->c_faddr,
98                         RDS_PROTOCOL_MAJOR(conn->c_version),
99                         RDS_PROTOCOL_MINOR(conn->c_version),
100                         ic->i_flowctl ? ", flow control" : "");
101
102         rds_connect_complete(conn);
103 }
104
105 static void rds_iw_cm_fill_conn_param(struct rds_connection *conn,
106                         struct rdma_conn_param *conn_param,
107                         struct rds_iw_connect_private *dp,
108                         u32 protocol_version)
109 {
110         struct rds_iw_connection *ic = conn->c_transport_data;
111
112         memset(conn_param, 0, sizeof(struct rdma_conn_param));
113         /* XXX tune these? */
114         conn_param->responder_resources = 1;
115         conn_param->initiator_depth = 1;
116
117         if (dp) {
118                 memset(dp, 0, sizeof(*dp));
119                 dp->dp_saddr = conn->c_laddr;
120                 dp->dp_daddr = conn->c_faddr;
121                 dp->dp_protocol_major = RDS_PROTOCOL_MAJOR(protocol_version);
122                 dp->dp_protocol_minor = RDS_PROTOCOL_MINOR(protocol_version);
123                 dp->dp_protocol_minor_mask = cpu_to_be16(RDS_IW_SUPPORTED_PROTOCOLS);
124                 dp->dp_ack_seq = rds_iw_piggyb_ack(ic);
125
126                 /* Advertise flow control */
127                 if (ic->i_flowctl) {
128                         unsigned int credits;
129
130                         credits = IB_GET_POST_CREDITS(atomic_read(&ic->i_credits));
131                         dp->dp_credit = cpu_to_be32(credits);
132                         atomic_sub(IB_SET_POST_CREDITS(credits), &ic->i_credits);
133                 }
134
135                 conn_param->private_data = dp;
136                 conn_param->private_data_len = sizeof(*dp);
137         }
138 }
139
140 static void rds_iw_cq_event_handler(struct ib_event *event, void *data)
141 {
142         rdsdebug("event %u data %p\n", event->event, data);
143 }
144
145 static void rds_iw_qp_event_handler(struct ib_event *event, void *data)
146 {
147         struct rds_connection *conn = data;
148         struct rds_iw_connection *ic = conn->c_transport_data;
149
150         rdsdebug("conn %p ic %p event %u\n", conn, ic, event->event);
151
152         switch (event->event) {
153         case IB_EVENT_COMM_EST:
154                 rdma_notify(ic->i_cm_id, IB_EVENT_COMM_EST);
155                 break;
156         case IB_EVENT_QP_REQ_ERR:
157         case IB_EVENT_QP_FATAL:
158         default:
159                 rds_iw_conn_error(conn, "RDS/IW: Fatal QP Event %u - connection %pI4->%pI4...reconnecting\n",
160                         event->event, &conn->c_laddr,
161                         &conn->c_faddr);
162                 break;
163         }
164 }
165
166 /*
167  * Create a QP
168  */
169 static int rds_iw_init_qp_attrs(struct ib_qp_init_attr *attr,
170                 struct rds_iw_device *rds_iwdev,
171                 struct rds_iw_work_ring *send_ring,
172                 void (*send_cq_handler)(struct ib_cq *, void *),
173                 struct rds_iw_work_ring *recv_ring,
174                 void (*recv_cq_handler)(struct ib_cq *, void *),
175                 void *context)
176 {
177         struct ib_device *dev = rds_iwdev->dev;
178         unsigned int send_size, recv_size;
179         int ret;
180
181         /* The offset of 1 is to accomodate the additional ACK WR. */
182         send_size = min_t(unsigned int, rds_iwdev->max_wrs, rds_iw_sysctl_max_send_wr + 1);
183         recv_size = min_t(unsigned int, rds_iwdev->max_wrs, rds_iw_sysctl_max_recv_wr + 1);
184         rds_iw_ring_resize(send_ring, send_size - 1);
185         rds_iw_ring_resize(recv_ring, recv_size - 1);
186
187         memset(attr, 0, sizeof(*attr));
188         attr->event_handler = rds_iw_qp_event_handler;
189         attr->qp_context = context;
190         attr->cap.max_send_wr = send_size;
191         attr->cap.max_recv_wr = recv_size;
192         attr->cap.max_send_sge = rds_iwdev->max_sge;
193         attr->cap.max_recv_sge = RDS_IW_RECV_SGE;
194         attr->sq_sig_type = IB_SIGNAL_REQ_WR;
195         attr->qp_type = IB_QPT_RC;
196
197         attr->send_cq = ib_create_cq(dev, send_cq_handler,
198                                      rds_iw_cq_event_handler,
199                                      context, send_size, 0);
200         if (IS_ERR(attr->send_cq)) {
201                 ret = PTR_ERR(attr->send_cq);
202                 attr->send_cq = NULL;
203                 rdsdebug("ib_create_cq send failed: %d\n", ret);
204                 goto out;
205         }
206
207         attr->recv_cq = ib_create_cq(dev, recv_cq_handler,
208                                      rds_iw_cq_event_handler,
209                                      context, recv_size, 0);
210         if (IS_ERR(attr->recv_cq)) {
211                 ret = PTR_ERR(attr->recv_cq);
212                 attr->recv_cq = NULL;
213                 rdsdebug("ib_create_cq send failed: %d\n", ret);
214                 goto out;
215         }
216
217         ret = ib_req_notify_cq(attr->send_cq, IB_CQ_NEXT_COMP);
218         if (ret) {
219                 rdsdebug("ib_req_notify_cq send failed: %d\n", ret);
220                 goto out;
221         }
222
223         ret = ib_req_notify_cq(attr->recv_cq, IB_CQ_SOLICITED);
224         if (ret) {
225                 rdsdebug("ib_req_notify_cq recv failed: %d\n", ret);
226                 goto out;
227         }
228
229 out:
230         if (ret) {
231                 if (attr->send_cq)
232                         ib_destroy_cq(attr->send_cq);
233                 if (attr->recv_cq)
234                         ib_destroy_cq(attr->recv_cq);
235         }
236         return ret;
237 }
238
239 /*
240  * This needs to be very careful to not leave IS_ERR pointers around for
241  * cleanup to trip over.
242  */
243 static int rds_iw_setup_qp(struct rds_connection *conn)
244 {
245         struct rds_iw_connection *ic = conn->c_transport_data;
246         struct ib_device *dev = ic->i_cm_id->device;
247         struct ib_qp_init_attr attr;
248         struct rds_iw_device *rds_iwdev;
249         int ret;
250
251         /* rds_iw_add_one creates a rds_iw_device object per IB device,
252          * and allocates a protection domain, memory range and MR pool
253          * for each.  If that fails for any reason, it will not register
254          * the rds_iwdev at all.
255          */
256         rds_iwdev = ib_get_client_data(dev, &rds_iw_client);
257         if (rds_iwdev == NULL) {
258                 if (printk_ratelimit())
259                         printk(KERN_NOTICE "RDS/IW: No client_data for device %s\n",
260                                         dev->name);
261                 return -EOPNOTSUPP;
262         }
263
264         /* Protection domain and memory range */
265         ic->i_pd = rds_iwdev->pd;
266         ic->i_mr = rds_iwdev->mr;
267
268         ret = rds_iw_init_qp_attrs(&attr, rds_iwdev,
269                         &ic->i_send_ring, rds_iw_send_cq_comp_handler,
270                         &ic->i_recv_ring, rds_iw_recv_cq_comp_handler,
271                         conn);
272         if (ret < 0)
273                 goto out;
274
275         ic->i_send_cq = attr.send_cq;
276         ic->i_recv_cq = attr.recv_cq;
277
278         /*
279          * XXX this can fail if max_*_wr is too large?  Are we supposed
280          * to back off until we get a value that the hardware can support?
281          */
282         ret = rdma_create_qp(ic->i_cm_id, ic->i_pd, &attr);
283         if (ret) {
284                 rdsdebug("rdma_create_qp failed: %d\n", ret);
285                 goto out;
286         }
287
288         ic->i_send_hdrs = ib_dma_alloc_coherent(dev,
289                                            ic->i_send_ring.w_nr *
290                                                 sizeof(struct rds_header),
291                                            &ic->i_send_hdrs_dma, GFP_KERNEL);
292         if (ic->i_send_hdrs == NULL) {
293                 ret = -ENOMEM;
294                 rdsdebug("ib_dma_alloc_coherent send failed\n");
295                 goto out;
296         }
297
298         ic->i_recv_hdrs = ib_dma_alloc_coherent(dev,
299                                            ic->i_recv_ring.w_nr *
300                                                 sizeof(struct rds_header),
301                                            &ic->i_recv_hdrs_dma, GFP_KERNEL);
302         if (ic->i_recv_hdrs == NULL) {
303                 ret = -ENOMEM;
304                 rdsdebug("ib_dma_alloc_coherent recv failed\n");
305                 goto out;
306         }
307
308         ic->i_ack = ib_dma_alloc_coherent(dev, sizeof(struct rds_header),
309                                        &ic->i_ack_dma, GFP_KERNEL);
310         if (ic->i_ack == NULL) {
311                 ret = -ENOMEM;
312                 rdsdebug("ib_dma_alloc_coherent ack failed\n");
313                 goto out;
314         }
315
316         ic->i_sends = vmalloc(ic->i_send_ring.w_nr * sizeof(struct rds_iw_send_work));
317         if (ic->i_sends == NULL) {
318                 ret = -ENOMEM;
319                 rdsdebug("send allocation failed\n");
320                 goto out;
321         }
322         rds_iw_send_init_ring(ic);
323
324         ic->i_recvs = vmalloc(ic->i_recv_ring.w_nr * sizeof(struct rds_iw_recv_work));
325         if (ic->i_recvs == NULL) {
326                 ret = -ENOMEM;
327                 rdsdebug("recv allocation failed\n");
328                 goto out;
329         }
330
331         rds_iw_recv_init_ring(ic);
332         rds_iw_recv_init_ack(ic);
333
334         /* Post receive buffers - as a side effect, this will update
335          * the posted credit count. */
336         rds_iw_recv_refill(conn, GFP_KERNEL, GFP_HIGHUSER, 1);
337
338         rdsdebug("conn %p pd %p mr %p cq %p %p\n", conn, ic->i_pd, ic->i_mr,
339                  ic->i_send_cq, ic->i_recv_cq);
340
341 out:
342         return ret;
343 }
344
345 static u32 rds_iw_protocol_compatible(const struct rds_iw_connect_private *dp)
346 {
347         u16 common;
348         u32 version = 0;
349
350         /* rdma_cm private data is odd - when there is any private data in the
351          * request, we will be given a pretty large buffer without telling us the
352          * original size. The only way to tell the difference is by looking at
353          * the contents, which are initialized to zero.
354          * If the protocol version fields aren't set, this is a connection attempt
355          * from an older version. This could could be 3.0 or 2.0 - we can't tell.
356          * We really should have changed this for OFED 1.3 :-( */
357         if (dp->dp_protocol_major == 0)
358                 return RDS_PROTOCOL_3_0;
359
360         common = be16_to_cpu(dp->dp_protocol_minor_mask) & RDS_IW_SUPPORTED_PROTOCOLS;
361         if (dp->dp_protocol_major == 3 && common) {
362                 version = RDS_PROTOCOL_3_0;
363                 while ((common >>= 1) != 0)
364                         version++;
365         } else if (printk_ratelimit()) {
366                 printk(KERN_NOTICE "RDS: Connection from %pI4 using "
367                         "incompatible protocol version %u.%u\n",
368                         &dp->dp_saddr,
369                         dp->dp_protocol_major,
370                         dp->dp_protocol_minor);
371         }
372         return version;
373 }
374
375 int rds_iw_cm_handle_connect(struct rdma_cm_id *cm_id,
376                                     struct rdma_cm_event *event)
377 {
378         const struct rds_iw_connect_private *dp = event->param.conn.private_data;
379         struct rds_iw_connect_private dp_rep;
380         struct rds_connection *conn = NULL;
381         struct rds_iw_connection *ic = NULL;
382         struct rdma_conn_param conn_param;
383         struct rds_iw_device *rds_iwdev;
384         u32 version;
385         int err, destroy = 1;
386
387         /* Check whether the remote protocol version matches ours. */
388         version = rds_iw_protocol_compatible(dp);
389         if (!version)
390                 goto out;
391
392         rdsdebug("saddr %pI4 daddr %pI4 RDSv%u.%u\n",
393                  &dp->dp_saddr, &dp->dp_daddr,
394                  RDS_PROTOCOL_MAJOR(version), RDS_PROTOCOL_MINOR(version));
395
396         conn = rds_conn_create(dp->dp_daddr, dp->dp_saddr, &rds_iw_transport,
397                                GFP_KERNEL);
398         if (IS_ERR(conn)) {
399                 rdsdebug("rds_conn_create failed (%ld)\n", PTR_ERR(conn));
400                 conn = NULL;
401                 goto out;
402         }
403
404         /*
405          * The connection request may occur while the
406          * previous connection exist, e.g. in case of failover.
407          * But as connections may be initiated simultaneously
408          * by both hosts, we have a random backoff mechanism -
409          * see the comment above rds_queue_reconnect()
410          */
411         mutex_lock(&conn->c_cm_lock);
412         if (!rds_conn_transition(conn, RDS_CONN_DOWN, RDS_CONN_CONNECTING)) {
413                 if (rds_conn_state(conn) == RDS_CONN_UP) {
414                         rdsdebug("incoming connect while connecting\n");
415                         rds_conn_drop(conn);
416                         rds_iw_stats_inc(s_iw_listen_closed_stale);
417                 } else
418                 if (rds_conn_state(conn) == RDS_CONN_CONNECTING) {
419                         /* Wait and see - our connect may still be succeeding */
420                         rds_iw_stats_inc(s_iw_connect_raced);
421                 }
422                 mutex_unlock(&conn->c_cm_lock);
423                 goto out;
424         }
425
426         ic = conn->c_transport_data;
427
428         rds_iw_set_protocol(conn, version);
429         rds_iw_set_flow_control(conn, be32_to_cpu(dp->dp_credit));
430
431         /* If the peer gave us the last packet it saw, process this as if
432          * we had received a regular ACK. */
433         if (dp->dp_ack_seq)
434                 rds_send_drop_acked(conn, be64_to_cpu(dp->dp_ack_seq), NULL);
435
436         BUG_ON(cm_id->context);
437         BUG_ON(ic->i_cm_id);
438
439         ic->i_cm_id = cm_id;
440         cm_id->context = conn;
441
442         rds_iwdev = ib_get_client_data(cm_id->device, &rds_iw_client);
443         ic->i_dma_local_lkey = rds_iwdev->dma_local_lkey;
444
445         /* We got halfway through setting up the ib_connection, if we
446          * fail now, we have to take the long route out of this mess. */
447         destroy = 0;
448
449         err = rds_iw_setup_qp(conn);
450         if (err) {
451                 rds_iw_conn_error(conn, "rds_iw_setup_qp failed (%d)\n", err);
452                 goto out;
453         }
454
455         rds_iw_cm_fill_conn_param(conn, &conn_param, &dp_rep, version);
456
457         /* rdma_accept() calls rdma_reject() internally if it fails */
458         err = rdma_accept(cm_id, &conn_param);
459         mutex_unlock(&conn->c_cm_lock);
460         if (err) {
461                 rds_iw_conn_error(conn, "rdma_accept failed (%d)\n", err);
462                 goto out;
463         }
464
465         return 0;
466
467 out:
468         rdma_reject(cm_id, NULL, 0);
469         return destroy;
470 }
471
472
473 int rds_iw_cm_initiate_connect(struct rdma_cm_id *cm_id)
474 {
475         struct rds_connection *conn = cm_id->context;
476         struct rds_iw_connection *ic = conn->c_transport_data;
477         struct rdma_conn_param conn_param;
478         struct rds_iw_connect_private dp;
479         int ret;
480
481         /* If the peer doesn't do protocol negotiation, we must
482          * default to RDSv3.0 */
483         rds_iw_set_protocol(conn, RDS_PROTOCOL_3_0);
484         ic->i_flowctl = rds_iw_sysctl_flow_control;     /* advertise flow control */
485
486         ret = rds_iw_setup_qp(conn);
487         if (ret) {
488                 rds_iw_conn_error(conn, "rds_iw_setup_qp failed (%d)\n", ret);
489                 goto out;
490         }
491
492         rds_iw_cm_fill_conn_param(conn, &conn_param, &dp, RDS_PROTOCOL_VERSION);
493
494         ret = rdma_connect(cm_id, &conn_param);
495         if (ret)
496                 rds_iw_conn_error(conn, "rdma_connect failed (%d)\n", ret);
497
498 out:
499         /* Beware - returning non-zero tells the rdma_cm to destroy
500          * the cm_id. We should certainly not do it as long as we still
501          * "own" the cm_id. */
502         if (ret) {
503                 struct rds_iw_connection *ic = conn->c_transport_data;
504
505                 if (ic->i_cm_id == cm_id)
506                         ret = 0;
507         }
508         return ret;
509 }
510
511 int rds_iw_conn_connect(struct rds_connection *conn)
512 {
513         struct rds_iw_connection *ic = conn->c_transport_data;
514         struct rds_iw_device *rds_iwdev;
515         struct sockaddr_in src, dest;
516         int ret;
517
518         /* XXX I wonder what affect the port space has */
519         /* delegate cm event handler to rdma_transport */
520         ic->i_cm_id = rdma_create_id(rds_rdma_cm_event_handler, conn,
521                                      RDMA_PS_TCP);
522         if (IS_ERR(ic->i_cm_id)) {
523                 ret = PTR_ERR(ic->i_cm_id);
524                 ic->i_cm_id = NULL;
525                 rdsdebug("rdma_create_id() failed: %d\n", ret);
526                 goto out;
527         }
528
529         rdsdebug("created cm id %p for conn %p\n", ic->i_cm_id, conn);
530
531         src.sin_family = AF_INET;
532         src.sin_addr.s_addr = (__force u32)conn->c_laddr;
533         src.sin_port = (__force u16)htons(0);
534
535         /* First, bind to the local address and device. */
536         ret = rdma_bind_addr(ic->i_cm_id, (struct sockaddr *) &src);
537         if (ret) {
538                 rdsdebug("rdma_bind_addr(%pI4) failed: %d\n",
539                                 &conn->c_laddr, ret);
540                 rdma_destroy_id(ic->i_cm_id);
541                 ic->i_cm_id = NULL;
542                 goto out;
543         }
544
545         rds_iwdev = ib_get_client_data(ic->i_cm_id->device, &rds_iw_client);
546         ic->i_dma_local_lkey = rds_iwdev->dma_local_lkey;
547
548         dest.sin_family = AF_INET;
549         dest.sin_addr.s_addr = (__force u32)conn->c_faddr;
550         dest.sin_port = (__force u16)htons(RDS_PORT);
551
552         ret = rdma_resolve_addr(ic->i_cm_id, (struct sockaddr *)&src,
553                                 (struct sockaddr *)&dest,
554                                 RDS_RDMA_RESOLVE_TIMEOUT_MS);
555         if (ret) {
556                 rdsdebug("addr resolve failed for cm id %p: %d\n", ic->i_cm_id,
557                          ret);
558                 rdma_destroy_id(ic->i_cm_id);
559                 ic->i_cm_id = NULL;
560         }
561
562 out:
563         return ret;
564 }
565
566 /*
567  * This is so careful about only cleaning up resources that were built up
568  * so that it can be called at any point during startup.  In fact it
569  * can be called multiple times for a given connection.
570  */
571 void rds_iw_conn_shutdown(struct rds_connection *conn)
572 {
573         struct rds_iw_connection *ic = conn->c_transport_data;
574         int err = 0;
575         struct ib_qp_attr qp_attr;
576
577         rdsdebug("cm %p pd %p cq %p %p qp %p\n", ic->i_cm_id,
578                  ic->i_pd, ic->i_send_cq, ic->i_recv_cq,
579                  ic->i_cm_id ? ic->i_cm_id->qp : NULL);
580
581         if (ic->i_cm_id) {
582                 struct ib_device *dev = ic->i_cm_id->device;
583
584                 rdsdebug("disconnecting cm %p\n", ic->i_cm_id);
585                 err = rdma_disconnect(ic->i_cm_id);
586                 if (err) {
587                         /* Actually this may happen quite frequently, when
588                          * an outgoing connect raced with an incoming connect.
589                          */
590                         rdsdebug("rds_iw_conn_shutdown: failed to disconnect,"
591                                    " cm: %p err %d\n", ic->i_cm_id, err);
592                 }
593
594                 if (ic->i_cm_id->qp) {
595                         qp_attr.qp_state = IB_QPS_ERR;
596                         ib_modify_qp(ic->i_cm_id->qp, &qp_attr, IB_QP_STATE);
597                 }
598
599                 wait_event(rds_iw_ring_empty_wait,
600                         rds_iw_ring_empty(&ic->i_send_ring) &&
601                         rds_iw_ring_empty(&ic->i_recv_ring));
602
603                 if (ic->i_send_hdrs)
604                         ib_dma_free_coherent(dev,
605                                            ic->i_send_ring.w_nr *
606                                                 sizeof(struct rds_header),
607                                            ic->i_send_hdrs,
608                                            ic->i_send_hdrs_dma);
609
610                 if (ic->i_recv_hdrs)
611                         ib_dma_free_coherent(dev,
612                                            ic->i_recv_ring.w_nr *
613                                                 sizeof(struct rds_header),
614                                            ic->i_recv_hdrs,
615                                            ic->i_recv_hdrs_dma);
616
617                 if (ic->i_ack)
618                         ib_dma_free_coherent(dev, sizeof(struct rds_header),
619                                              ic->i_ack, ic->i_ack_dma);
620
621                 if (ic->i_sends)
622                         rds_iw_send_clear_ring(ic);
623                 if (ic->i_recvs)
624                         rds_iw_recv_clear_ring(ic);
625
626                 if (ic->i_cm_id->qp)
627                         rdma_destroy_qp(ic->i_cm_id);
628                 if (ic->i_send_cq)
629                         ib_destroy_cq(ic->i_send_cq);
630                 if (ic->i_recv_cq)
631                         ib_destroy_cq(ic->i_recv_cq);
632
633                 /*
634                  * If associated with an rds_iw_device:
635                  *      Move connection back to the nodev list.
636                  *      Remove cm_id from the device cm_id list.
637                  */
638                 if (ic->rds_iwdev)
639                         rds_iw_remove_conn(ic->rds_iwdev, conn);
640
641                 rdma_destroy_id(ic->i_cm_id);
642
643                 ic->i_cm_id = NULL;
644                 ic->i_pd = NULL;
645                 ic->i_mr = NULL;
646                 ic->i_send_cq = NULL;
647                 ic->i_recv_cq = NULL;
648                 ic->i_send_hdrs = NULL;
649                 ic->i_recv_hdrs = NULL;
650                 ic->i_ack = NULL;
651         }
652         BUG_ON(ic->rds_iwdev);
653
654         /* Clear pending transmit */
655         if (ic->i_rm) {
656                 rds_message_put(ic->i_rm);
657                 ic->i_rm = NULL;
658         }
659
660         /* Clear the ACK state */
661         clear_bit(IB_ACK_IN_FLIGHT, &ic->i_ack_flags);
662 #ifdef KERNEL_HAS_ATOMIC64
663         atomic64_set(&ic->i_ack_next, 0);
664 #else
665         ic->i_ack_next = 0;
666 #endif
667         ic->i_ack_recv = 0;
668
669         /* Clear flow control state */
670         ic->i_flowctl = 0;
671         atomic_set(&ic->i_credits, 0);
672
673         rds_iw_ring_init(&ic->i_send_ring, rds_iw_sysctl_max_send_wr);
674         rds_iw_ring_init(&ic->i_recv_ring, rds_iw_sysctl_max_recv_wr);
675
676         if (ic->i_iwinc) {
677                 rds_inc_put(&ic->i_iwinc->ii_inc);
678                 ic->i_iwinc = NULL;
679         }
680
681         vfree(ic->i_sends);
682         ic->i_sends = NULL;
683         vfree(ic->i_recvs);
684         ic->i_recvs = NULL;
685         rdsdebug("shutdown complete\n");
686 }
687
688 int rds_iw_conn_alloc(struct rds_connection *conn, gfp_t gfp)
689 {
690         struct rds_iw_connection *ic;
691         unsigned long flags;
692
693         /* XXX too lazy? */
694         ic = kzalloc(sizeof(struct rds_iw_connection), GFP_KERNEL);
695         if (ic == NULL)
696                 return -ENOMEM;
697
698         INIT_LIST_HEAD(&ic->iw_node);
699         tasklet_init(&ic->i_recv_tasklet, rds_iw_recv_tasklet_fn,
700                      (unsigned long) ic);
701         mutex_init(&ic->i_recv_mutex);
702 #ifndef KERNEL_HAS_ATOMIC64
703         spin_lock_init(&ic->i_ack_lock);
704 #endif
705
706         /*
707          * rds_iw_conn_shutdown() waits for these to be emptied so they
708          * must be initialized before it can be called.
709          */
710         rds_iw_ring_init(&ic->i_send_ring, rds_iw_sysctl_max_send_wr);
711         rds_iw_ring_init(&ic->i_recv_ring, rds_iw_sysctl_max_recv_wr);
712
713         ic->conn = conn;
714         conn->c_transport_data = ic;
715
716         spin_lock_irqsave(&iw_nodev_conns_lock, flags);
717         list_add_tail(&ic->iw_node, &iw_nodev_conns);
718         spin_unlock_irqrestore(&iw_nodev_conns_lock, flags);
719
720
721         rdsdebug("conn %p conn ic %p\n", conn, conn->c_transport_data);
722         return 0;
723 }
724
725 /*
726  * Free a connection. Connection must be shut down and not set for reconnect.
727  */
728 void rds_iw_conn_free(void *arg)
729 {
730         struct rds_iw_connection *ic = arg;
731         spinlock_t      *lock_ptr;
732
733         rdsdebug("ic %p\n", ic);
734
735         /*
736          * Conn is either on a dev's list or on the nodev list.
737          * A race with shutdown() or connect() would cause problems
738          * (since rds_iwdev would change) but that should never happen.
739          */
740         lock_ptr = ic->rds_iwdev ? &ic->rds_iwdev->spinlock : &iw_nodev_conns_lock;
741
742         spin_lock_irq(lock_ptr);
743         list_del(&ic->iw_node);
744         spin_unlock_irq(lock_ptr);
745
746         kfree(ic);
747 }
748
749 /*
750  * An error occurred on the connection
751  */
752 void
753 __rds_iw_conn_error(struct rds_connection *conn, const char *fmt, ...)
754 {
755         va_list ap;
756
757         rds_conn_drop(conn);
758
759         va_start(ap, fmt);
760         vprintk(fmt, ap);
761         va_end(ap);
762 }