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/slab.h>
36 #include <linux/vmalloc.h>
37 #include <linux/ratelimit.h>
38 
39 #include "rds.h"
40 #include "iw.h"
41 
42 /*
43  * Set the selected protocol version
44  */
rds_iw_set_protocol(struct rds_connection * conn,unsigned int version)45 static void rds_iw_set_protocol(struct rds_connection *conn, unsigned int version)
46 {
47 	conn->c_version = version;
48 }
49 
50 /*
51  * Set up flow control
52  */
rds_iw_set_flow_control(struct rds_connection * conn,u32 credits)53 static void rds_iw_set_flow_control(struct rds_connection *conn, u32 credits)
54 {
55 	struct rds_iw_connection *ic = conn->c_transport_data;
56 
57 	if (rds_iw_sysctl_flow_control && credits != 0) {
58 		/* We're doing flow control */
59 		ic->i_flowctl = 1;
60 		rds_iw_send_add_credits(conn, credits);
61 	} else {
62 		ic->i_flowctl = 0;
63 	}
64 }
65 
66 /*
67  * Connection established.
68  * We get here for both outgoing and incoming connection.
69  */
rds_iw_cm_connect_complete(struct rds_connection * conn,struct rdma_cm_event * event)70 void rds_iw_cm_connect_complete(struct rds_connection *conn, struct rdma_cm_event *event)
71 {
72 	const struct rds_iw_connect_private *dp = NULL;
73 	struct rds_iw_connection *ic = conn->c_transport_data;
74 	struct rds_iw_device *rds_iwdev;
75 	int err;
76 
77 	if (event->param.conn.private_data_len) {
78 		dp = event->param.conn.private_data;
79 
80 		rds_iw_set_protocol(conn,
81 				RDS_PROTOCOL(dp->dp_protocol_major,
82 					dp->dp_protocol_minor));
83 		rds_iw_set_flow_control(conn, be32_to_cpu(dp->dp_credit));
84 	}
85 
86 	/* update ib_device with this local ipaddr & conn */
87 	rds_iwdev = ib_get_client_data(ic->i_cm_id->device, &rds_iw_client);
88 	err = rds_iw_update_cm_id(rds_iwdev, ic->i_cm_id);
89 	if (err)
90 		printk(KERN_ERR "rds_iw_update_ipaddr failed (%d)\n", err);
91 	rds_iw_add_conn(rds_iwdev, conn);
92 
93 	/* If the peer gave us the last packet it saw, process this as if
94 	 * we had received a regular ACK. */
95 	if (dp && dp->dp_ack_seq)
96 		rds_send_drop_acked(conn, be64_to_cpu(dp->dp_ack_seq), NULL);
97 
98 	printk(KERN_NOTICE "RDS/IW: connected to %pI4<->%pI4 version %u.%u%s\n",
99 			&conn->c_laddr, &conn->c_faddr,
100 			RDS_PROTOCOL_MAJOR(conn->c_version),
101 			RDS_PROTOCOL_MINOR(conn->c_version),
102 			ic->i_flowctl ? ", flow control" : "");
103 
104 	rds_connect_complete(conn);
105 }
106 
rds_iw_cm_fill_conn_param(struct rds_connection * conn,struct rdma_conn_param * conn_param,struct rds_iw_connect_private * dp,u32 protocol_version)107 static void rds_iw_cm_fill_conn_param(struct rds_connection *conn,
108 			struct rdma_conn_param *conn_param,
109 			struct rds_iw_connect_private *dp,
110 			u32 protocol_version)
111 {
112 	struct rds_iw_connection *ic = conn->c_transport_data;
113 
114 	memset(conn_param, 0, sizeof(struct rdma_conn_param));
115 	/* XXX tune these? */
116 	conn_param->responder_resources = 1;
117 	conn_param->initiator_depth = 1;
118 
119 	if (dp) {
120 		memset(dp, 0, sizeof(*dp));
121 		dp->dp_saddr = conn->c_laddr;
122 		dp->dp_daddr = conn->c_faddr;
123 		dp->dp_protocol_major = RDS_PROTOCOL_MAJOR(protocol_version);
124 		dp->dp_protocol_minor = RDS_PROTOCOL_MINOR(protocol_version);
125 		dp->dp_protocol_minor_mask = cpu_to_be16(RDS_IW_SUPPORTED_PROTOCOLS);
126 		dp->dp_ack_seq = rds_iw_piggyb_ack(ic);
127 
128 		/* Advertise flow control */
129 		if (ic->i_flowctl) {
130 			unsigned int credits;
131 
132 			credits = IB_GET_POST_CREDITS(atomic_read(&ic->i_credits));
133 			dp->dp_credit = cpu_to_be32(credits);
134 			atomic_sub(IB_SET_POST_CREDITS(credits), &ic->i_credits);
135 		}
136 
137 		conn_param->private_data = dp;
138 		conn_param->private_data_len = sizeof(*dp);
139 	}
140 }
141 
rds_iw_cq_event_handler(struct ib_event * event,void * data)142 static void rds_iw_cq_event_handler(struct ib_event *event, void *data)
143 {
144 	rdsdebug("event %u data %p\n", event->event, data);
145 }
146 
rds_iw_qp_event_handler(struct ib_event * event,void * data)147 static void rds_iw_qp_event_handler(struct ib_event *event, void *data)
148 {
149 	struct rds_connection *conn = data;
150 	struct rds_iw_connection *ic = conn->c_transport_data;
151 
152 	rdsdebug("conn %p ic %p event %u\n", conn, ic, event->event);
153 
154 	switch (event->event) {
155 	case IB_EVENT_COMM_EST:
156 		rdma_notify(ic->i_cm_id, IB_EVENT_COMM_EST);
157 		break;
158 	case IB_EVENT_QP_REQ_ERR:
159 	case IB_EVENT_QP_FATAL:
160 	default:
161 		rdsdebug("Fatal QP Event %u "
162 			"- connection %pI4->%pI4, reconnecting\n",
163 			event->event, &conn->c_laddr,
164 			&conn->c_faddr);
165 		rds_conn_drop(conn);
166 		break;
167 	}
168 }
169 
170 /*
171  * Create a QP
172  */
rds_iw_init_qp_attrs(struct ib_qp_init_attr * attr,struct rds_iw_device * rds_iwdev,struct rds_iw_work_ring * send_ring,void (* send_cq_handler)(struct ib_cq *,void *),struct rds_iw_work_ring * recv_ring,void (* recv_cq_handler)(struct ib_cq *,void *),void * context)173 static int rds_iw_init_qp_attrs(struct ib_qp_init_attr *attr,
174 		struct rds_iw_device *rds_iwdev,
175 		struct rds_iw_work_ring *send_ring,
176 		void (*send_cq_handler)(struct ib_cq *, void *),
177 		struct rds_iw_work_ring *recv_ring,
178 		void (*recv_cq_handler)(struct ib_cq *, void *),
179 		void *context)
180 {
181 	struct ib_device *dev = rds_iwdev->dev;
182 	unsigned int send_size, recv_size;
183 	int ret;
184 
185 	/* The offset of 1 is to accommodate the additional ACK WR. */
186 	send_size = min_t(unsigned int, rds_iwdev->max_wrs, rds_iw_sysctl_max_send_wr + 1);
187 	recv_size = min_t(unsigned int, rds_iwdev->max_wrs, rds_iw_sysctl_max_recv_wr + 1);
188 	rds_iw_ring_resize(send_ring, send_size - 1);
189 	rds_iw_ring_resize(recv_ring, recv_size - 1);
190 
191 	memset(attr, 0, sizeof(*attr));
192 	attr->event_handler = rds_iw_qp_event_handler;
193 	attr->qp_context = context;
194 	attr->cap.max_send_wr = send_size;
195 	attr->cap.max_recv_wr = recv_size;
196 	attr->cap.max_send_sge = rds_iwdev->max_sge;
197 	attr->cap.max_recv_sge = RDS_IW_RECV_SGE;
198 	attr->sq_sig_type = IB_SIGNAL_REQ_WR;
199 	attr->qp_type = IB_QPT_RC;
200 
201 	attr->send_cq = ib_create_cq(dev, send_cq_handler,
202 				     rds_iw_cq_event_handler,
203 				     context, send_size, 0);
204 	if (IS_ERR(attr->send_cq)) {
205 		ret = PTR_ERR(attr->send_cq);
206 		attr->send_cq = NULL;
207 		rdsdebug("ib_create_cq send failed: %d\n", ret);
208 		goto out;
209 	}
210 
211 	attr->recv_cq = ib_create_cq(dev, recv_cq_handler,
212 				     rds_iw_cq_event_handler,
213 				     context, recv_size, 0);
214 	if (IS_ERR(attr->recv_cq)) {
215 		ret = PTR_ERR(attr->recv_cq);
216 		attr->recv_cq = NULL;
217 		rdsdebug("ib_create_cq send failed: %d\n", ret);
218 		goto out;
219 	}
220 
221 	ret = ib_req_notify_cq(attr->send_cq, IB_CQ_NEXT_COMP);
222 	if (ret) {
223 		rdsdebug("ib_req_notify_cq send failed: %d\n", ret);
224 		goto out;
225 	}
226 
227 	ret = ib_req_notify_cq(attr->recv_cq, IB_CQ_SOLICITED);
228 	if (ret) {
229 		rdsdebug("ib_req_notify_cq recv failed: %d\n", ret);
230 		goto out;
231 	}
232 
233 out:
234 	if (ret) {
235 		if (attr->send_cq)
236 			ib_destroy_cq(attr->send_cq);
237 		if (attr->recv_cq)
238 			ib_destroy_cq(attr->recv_cq);
239 	}
240 	return ret;
241 }
242 
243 /*
244  * This needs to be very careful to not leave IS_ERR pointers around for
245  * cleanup to trip over.
246  */
rds_iw_setup_qp(struct rds_connection * conn)247 static int rds_iw_setup_qp(struct rds_connection *conn)
248 {
249 	struct rds_iw_connection *ic = conn->c_transport_data;
250 	struct ib_device *dev = ic->i_cm_id->device;
251 	struct ib_qp_init_attr attr;
252 	struct rds_iw_device *rds_iwdev;
253 	int ret;
254 
255 	/* rds_iw_add_one creates a rds_iw_device object per IB device,
256 	 * and allocates a protection domain, memory range and MR pool
257 	 * for each.  If that fails for any reason, it will not register
258 	 * the rds_iwdev at all.
259 	 */
260 	rds_iwdev = ib_get_client_data(dev, &rds_iw_client);
261 	if (!rds_iwdev) {
262 		printk_ratelimited(KERN_NOTICE "RDS/IW: No client_data for device %s\n",
263 					dev->name);
264 		return -EOPNOTSUPP;
265 	}
266 
267 	/* Protection domain and memory range */
268 	ic->i_pd = rds_iwdev->pd;
269 	ic->i_mr = rds_iwdev->mr;
270 
271 	ret = rds_iw_init_qp_attrs(&attr, rds_iwdev,
272 			&ic->i_send_ring, rds_iw_send_cq_comp_handler,
273 			&ic->i_recv_ring, rds_iw_recv_cq_comp_handler,
274 			conn);
275 	if (ret < 0)
276 		goto out;
277 
278 	ic->i_send_cq = attr.send_cq;
279 	ic->i_recv_cq = attr.recv_cq;
280 
281 	/*
282 	 * XXX this can fail if max_*_wr is too large?  Are we supposed
283 	 * to back off until we get a value that the hardware can support?
284 	 */
285 	ret = rdma_create_qp(ic->i_cm_id, ic->i_pd, &attr);
286 	if (ret) {
287 		rdsdebug("rdma_create_qp failed: %d\n", ret);
288 		goto out;
289 	}
290 
291 	ic->i_send_hdrs = ib_dma_alloc_coherent(dev,
292 					   ic->i_send_ring.w_nr *
293 						sizeof(struct rds_header),
294 					   &ic->i_send_hdrs_dma, GFP_KERNEL);
295 	if (!ic->i_send_hdrs) {
296 		ret = -ENOMEM;
297 		rdsdebug("ib_dma_alloc_coherent send failed\n");
298 		goto out;
299 	}
300 
301 	ic->i_recv_hdrs = ib_dma_alloc_coherent(dev,
302 					   ic->i_recv_ring.w_nr *
303 						sizeof(struct rds_header),
304 					   &ic->i_recv_hdrs_dma, GFP_KERNEL);
305 	if (!ic->i_recv_hdrs) {
306 		ret = -ENOMEM;
307 		rdsdebug("ib_dma_alloc_coherent recv failed\n");
308 		goto out;
309 	}
310 
311 	ic->i_ack = ib_dma_alloc_coherent(dev, sizeof(struct rds_header),
312 				       &ic->i_ack_dma, GFP_KERNEL);
313 	if (!ic->i_ack) {
314 		ret = -ENOMEM;
315 		rdsdebug("ib_dma_alloc_coherent ack failed\n");
316 		goto out;
317 	}
318 
319 	ic->i_sends = vmalloc(ic->i_send_ring.w_nr * sizeof(struct rds_iw_send_work));
320 	if (!ic->i_sends) {
321 		ret = -ENOMEM;
322 		rdsdebug("send allocation failed\n");
323 		goto out;
324 	}
325 	rds_iw_send_init_ring(ic);
326 
327 	ic->i_recvs = vmalloc(ic->i_recv_ring.w_nr * sizeof(struct rds_iw_recv_work));
328 	if (!ic->i_recvs) {
329 		ret = -ENOMEM;
330 		rdsdebug("recv allocation failed\n");
331 		goto out;
332 	}
333 
334 	rds_iw_recv_init_ring(ic);
335 	rds_iw_recv_init_ack(ic);
336 
337 	/* Post receive buffers - as a side effect, this will update
338 	 * the posted credit count. */
339 	rds_iw_recv_refill(conn, GFP_KERNEL, GFP_HIGHUSER, 1);
340 
341 	rdsdebug("conn %p pd %p mr %p cq %p %p\n", conn, ic->i_pd, ic->i_mr,
342 		 ic->i_send_cq, ic->i_recv_cq);
343 
344 out:
345 	return ret;
346 }
347 
rds_iw_protocol_compatible(const struct rds_iw_connect_private * dp)348 static u32 rds_iw_protocol_compatible(const struct rds_iw_connect_private *dp)
349 {
350 	u16 common;
351 	u32 version = 0;
352 
353 	/* rdma_cm private data is odd - when there is any private data in the
354 	 * request, we will be given a pretty large buffer without telling us the
355 	 * original size. The only way to tell the difference is by looking at
356 	 * the contents, which are initialized to zero.
357 	 * If the protocol version fields aren't set, this is a connection attempt
358 	 * from an older version. This could could be 3.0 or 2.0 - we can't tell.
359 	 * We really should have changed this for OFED 1.3 :-( */
360 	if (dp->dp_protocol_major == 0)
361 		return RDS_PROTOCOL_3_0;
362 
363 	common = be16_to_cpu(dp->dp_protocol_minor_mask) & RDS_IW_SUPPORTED_PROTOCOLS;
364 	if (dp->dp_protocol_major == 3 && common) {
365 		version = RDS_PROTOCOL_3_0;
366 		while ((common >>= 1) != 0)
367 			version++;
368 	}
369 	printk_ratelimited(KERN_NOTICE "RDS: Connection from %pI4 using "
370 			"incompatible protocol version %u.%u\n",
371 			&dp->dp_saddr,
372 			dp->dp_protocol_major,
373 			dp->dp_protocol_minor);
374 	return version;
375 }
376 
rds_iw_cm_handle_connect(struct rdma_cm_id * cm_id,struct rdma_cm_event * event)377 int rds_iw_cm_handle_connect(struct rdma_cm_id *cm_id,
378 				    struct rdma_cm_event *event)
379 {
380 	const struct rds_iw_connect_private *dp = event->param.conn.private_data;
381 	struct rds_iw_connect_private dp_rep;
382 	struct rds_connection *conn = NULL;
383 	struct rds_iw_connection *ic = NULL;
384 	struct rdma_conn_param conn_param;
385 	struct rds_iw_device *rds_iwdev;
386 	u32 version;
387 	int err, destroy = 1;
388 
389 	/* Check whether the remote protocol version matches ours. */
390 	version = rds_iw_protocol_compatible(dp);
391 	if (!version)
392 		goto out;
393 
394 	rdsdebug("saddr %pI4 daddr %pI4 RDSv%u.%u\n",
395 		 &dp->dp_saddr, &dp->dp_daddr,
396 		 RDS_PROTOCOL_MAJOR(version), RDS_PROTOCOL_MINOR(version));
397 
398 	conn = rds_conn_create(dp->dp_daddr, dp->dp_saddr, &rds_iw_transport,
399 			       GFP_KERNEL);
400 	if (IS_ERR(conn)) {
401 		rdsdebug("rds_conn_create failed (%ld)\n", PTR_ERR(conn));
402 		conn = NULL;
403 		goto out;
404 	}
405 
406 	/*
407 	 * The connection request may occur while the
408 	 * previous connection exist, e.g. in case of failover.
409 	 * But as connections may be initiated simultaneously
410 	 * by both hosts, we have a random backoff mechanism -
411 	 * see the comment above rds_queue_reconnect()
412 	 */
413 	mutex_lock(&conn->c_cm_lock);
414 	if (!rds_conn_transition(conn, RDS_CONN_DOWN, RDS_CONN_CONNECTING)) {
415 		if (rds_conn_state(conn) == RDS_CONN_UP) {
416 			rdsdebug("incoming connect while connecting\n");
417 			rds_conn_drop(conn);
418 			rds_iw_stats_inc(s_iw_listen_closed_stale);
419 		} else
420 		if (rds_conn_state(conn) == RDS_CONN_CONNECTING) {
421 			/* Wait and see - our connect may still be succeeding */
422 			rds_iw_stats_inc(s_iw_connect_raced);
423 		}
424 		mutex_unlock(&conn->c_cm_lock);
425 		goto out;
426 	}
427 
428 	ic = conn->c_transport_data;
429 
430 	rds_iw_set_protocol(conn, version);
431 	rds_iw_set_flow_control(conn, be32_to_cpu(dp->dp_credit));
432 
433 	/* If the peer gave us the last packet it saw, process this as if
434 	 * we had received a regular ACK. */
435 	if (dp->dp_ack_seq)
436 		rds_send_drop_acked(conn, be64_to_cpu(dp->dp_ack_seq), NULL);
437 
438 	BUG_ON(cm_id->context);
439 	BUG_ON(ic->i_cm_id);
440 
441 	ic->i_cm_id = cm_id;
442 	cm_id->context = conn;
443 
444 	rds_iwdev = ib_get_client_data(cm_id->device, &rds_iw_client);
445 	ic->i_dma_local_lkey = rds_iwdev->dma_local_lkey;
446 
447 	/* We got halfway through setting up the ib_connection, if we
448 	 * fail now, we have to take the long route out of this mess. */
449 	destroy = 0;
450 
451 	err = rds_iw_setup_qp(conn);
452 	if (err) {
453 		rds_iw_conn_error(conn, "rds_iw_setup_qp failed (%d)\n", err);
454 		mutex_unlock(&conn->c_cm_lock);
455 		goto out;
456 	}
457 
458 	rds_iw_cm_fill_conn_param(conn, &conn_param, &dp_rep, version);
459 
460 	/* rdma_accept() calls rdma_reject() internally if it fails */
461 	err = rdma_accept(cm_id, &conn_param);
462 	mutex_unlock(&conn->c_cm_lock);
463 	if (err) {
464 		rds_iw_conn_error(conn, "rdma_accept failed (%d)\n", err);
465 		goto out;
466 	}
467 
468 	return 0;
469 
470 out:
471 	rdma_reject(cm_id, NULL, 0);
472 	return destroy;
473 }
474 
475 
rds_iw_cm_initiate_connect(struct rdma_cm_id * cm_id)476 int rds_iw_cm_initiate_connect(struct rdma_cm_id *cm_id)
477 {
478 	struct rds_connection *conn = cm_id->context;
479 	struct rds_iw_connection *ic = conn->c_transport_data;
480 	struct rdma_conn_param conn_param;
481 	struct rds_iw_connect_private dp;
482 	int ret;
483 
484 	/* If the peer doesn't do protocol negotiation, we must
485 	 * default to RDSv3.0 */
486 	rds_iw_set_protocol(conn, RDS_PROTOCOL_3_0);
487 	ic->i_flowctl = rds_iw_sysctl_flow_control;	/* advertise flow control */
488 
489 	ret = rds_iw_setup_qp(conn);
490 	if (ret) {
491 		rds_iw_conn_error(conn, "rds_iw_setup_qp failed (%d)\n", ret);
492 		goto out;
493 	}
494 
495 	rds_iw_cm_fill_conn_param(conn, &conn_param, &dp, RDS_PROTOCOL_VERSION);
496 
497 	ret = rdma_connect(cm_id, &conn_param);
498 	if (ret)
499 		rds_iw_conn_error(conn, "rdma_connect failed (%d)\n", ret);
500 
501 out:
502 	/* Beware - returning non-zero tells the rdma_cm to destroy
503 	 * the cm_id. We should certainly not do it as long as we still
504 	 * "own" the cm_id. */
505 	if (ret) {
506 		struct rds_iw_connection *ic = conn->c_transport_data;
507 
508 		if (ic->i_cm_id == cm_id)
509 			ret = 0;
510 	}
511 	return ret;
512 }
513 
rds_iw_conn_connect(struct rds_connection * conn)514 int rds_iw_conn_connect(struct rds_connection *conn)
515 {
516 	struct rds_iw_connection *ic = conn->c_transport_data;
517 	struct rds_iw_device *rds_iwdev;
518 	struct sockaddr_in src, dest;
519 	int ret;
520 
521 	/* XXX I wonder what affect the port space has */
522 	/* delegate cm event handler to rdma_transport */
523 	ic->i_cm_id = rdma_create_id(rds_rdma_cm_event_handler, conn,
524 				     RDMA_PS_TCP, IB_QPT_RC);
525 	if (IS_ERR(ic->i_cm_id)) {
526 		ret = PTR_ERR(ic->i_cm_id);
527 		ic->i_cm_id = NULL;
528 		rdsdebug("rdma_create_id() failed: %d\n", ret);
529 		goto out;
530 	}
531 
532 	rdsdebug("created cm id %p for conn %p\n", ic->i_cm_id, conn);
533 
534 	src.sin_family = AF_INET;
535 	src.sin_addr.s_addr = (__force u32)conn->c_laddr;
536 	src.sin_port = (__force u16)htons(0);
537 
538 	/* First, bind to the local address and device. */
539 	ret = rdma_bind_addr(ic->i_cm_id, (struct sockaddr *) &src);
540 	if (ret) {
541 		rdsdebug("rdma_bind_addr(%pI4) failed: %d\n",
542 				&conn->c_laddr, ret);
543 		rdma_destroy_id(ic->i_cm_id);
544 		ic->i_cm_id = NULL;
545 		goto out;
546 	}
547 
548 	rds_iwdev = ib_get_client_data(ic->i_cm_id->device, &rds_iw_client);
549 	ic->i_dma_local_lkey = rds_iwdev->dma_local_lkey;
550 
551 	dest.sin_family = AF_INET;
552 	dest.sin_addr.s_addr = (__force u32)conn->c_faddr;
553 	dest.sin_port = (__force u16)htons(RDS_PORT);
554 
555 	ret = rdma_resolve_addr(ic->i_cm_id, (struct sockaddr *)&src,
556 				(struct sockaddr *)&dest,
557 				RDS_RDMA_RESOLVE_TIMEOUT_MS);
558 	if (ret) {
559 		rdsdebug("addr resolve failed for cm id %p: %d\n", ic->i_cm_id,
560 			 ret);
561 		rdma_destroy_id(ic->i_cm_id);
562 		ic->i_cm_id = NULL;
563 	}
564 
565 out:
566 	return ret;
567 }
568 
569 /*
570  * This is so careful about only cleaning up resources that were built up
571  * so that it can be called at any point during startup.  In fact it
572  * can be called multiple times for a given connection.
573  */
rds_iw_conn_shutdown(struct rds_connection * conn)574 void rds_iw_conn_shutdown(struct rds_connection *conn)
575 {
576 	struct rds_iw_connection *ic = conn->c_transport_data;
577 	int err = 0;
578 	struct ib_qp_attr qp_attr;
579 
580 	rdsdebug("cm %p pd %p cq %p %p qp %p\n", ic->i_cm_id,
581 		 ic->i_pd, ic->i_send_cq, ic->i_recv_cq,
582 		 ic->i_cm_id ? ic->i_cm_id->qp : NULL);
583 
584 	if (ic->i_cm_id) {
585 		struct ib_device *dev = ic->i_cm_id->device;
586 
587 		rdsdebug("disconnecting cm %p\n", ic->i_cm_id);
588 		err = rdma_disconnect(ic->i_cm_id);
589 		if (err) {
590 			/* Actually this may happen quite frequently, when
591 			 * an outgoing connect raced with an incoming connect.
592 			 */
593 			rdsdebug("rds_iw_conn_shutdown: failed to disconnect,"
594 				   " cm: %p err %d\n", ic->i_cm_id, err);
595 		}
596 
597 		if (ic->i_cm_id->qp) {
598 			qp_attr.qp_state = IB_QPS_ERR;
599 			ib_modify_qp(ic->i_cm_id->qp, &qp_attr, IB_QP_STATE);
600 		}
601 
602 		wait_event(rds_iw_ring_empty_wait,
603 			rds_iw_ring_empty(&ic->i_send_ring) &&
604 			rds_iw_ring_empty(&ic->i_recv_ring));
605 
606 		if (ic->i_send_hdrs)
607 			ib_dma_free_coherent(dev,
608 					   ic->i_send_ring.w_nr *
609 						sizeof(struct rds_header),
610 					   ic->i_send_hdrs,
611 					   ic->i_send_hdrs_dma);
612 
613 		if (ic->i_recv_hdrs)
614 			ib_dma_free_coherent(dev,
615 					   ic->i_recv_ring.w_nr *
616 						sizeof(struct rds_header),
617 					   ic->i_recv_hdrs,
618 					   ic->i_recv_hdrs_dma);
619 
620 		if (ic->i_ack)
621 			ib_dma_free_coherent(dev, sizeof(struct rds_header),
622 					     ic->i_ack, ic->i_ack_dma);
623 
624 		if (ic->i_sends)
625 			rds_iw_send_clear_ring(ic);
626 		if (ic->i_recvs)
627 			rds_iw_recv_clear_ring(ic);
628 
629 		if (ic->i_cm_id->qp)
630 			rdma_destroy_qp(ic->i_cm_id);
631 		if (ic->i_send_cq)
632 			ib_destroy_cq(ic->i_send_cq);
633 		if (ic->i_recv_cq)
634 			ib_destroy_cq(ic->i_recv_cq);
635 
636 		/*
637 		 * If associated with an rds_iw_device:
638 		 * 	Move connection back to the nodev list.
639 		 * 	Remove cm_id from the device cm_id list.
640 		 */
641 		if (ic->rds_iwdev)
642 			rds_iw_remove_conn(ic->rds_iwdev, conn);
643 
644 		rdma_destroy_id(ic->i_cm_id);
645 
646 		ic->i_cm_id = NULL;
647 		ic->i_pd = NULL;
648 		ic->i_mr = NULL;
649 		ic->i_send_cq = NULL;
650 		ic->i_recv_cq = NULL;
651 		ic->i_send_hdrs = NULL;
652 		ic->i_recv_hdrs = NULL;
653 		ic->i_ack = NULL;
654 	}
655 	BUG_ON(ic->rds_iwdev);
656 
657 	/* Clear pending transmit */
658 	if (ic->i_rm) {
659 		rds_message_put(ic->i_rm);
660 		ic->i_rm = NULL;
661 	}
662 
663 	/* Clear the ACK state */
664 	clear_bit(IB_ACK_IN_FLIGHT, &ic->i_ack_flags);
665 #ifdef KERNEL_HAS_ATOMIC64
666 	atomic64_set(&ic->i_ack_next, 0);
667 #else
668 	ic->i_ack_next = 0;
669 #endif
670 	ic->i_ack_recv = 0;
671 
672 	/* Clear flow control state */
673 	ic->i_flowctl = 0;
674 	atomic_set(&ic->i_credits, 0);
675 
676 	rds_iw_ring_init(&ic->i_send_ring, rds_iw_sysctl_max_send_wr);
677 	rds_iw_ring_init(&ic->i_recv_ring, rds_iw_sysctl_max_recv_wr);
678 
679 	if (ic->i_iwinc) {
680 		rds_inc_put(&ic->i_iwinc->ii_inc);
681 		ic->i_iwinc = NULL;
682 	}
683 
684 	vfree(ic->i_sends);
685 	ic->i_sends = NULL;
686 	vfree(ic->i_recvs);
687 	ic->i_recvs = NULL;
688 	rdsdebug("shutdown complete\n");
689 }
690 
rds_iw_conn_alloc(struct rds_connection * conn,gfp_t gfp)691 int rds_iw_conn_alloc(struct rds_connection *conn, gfp_t gfp)
692 {
693 	struct rds_iw_connection *ic;
694 	unsigned long flags;
695 
696 	/* XXX too lazy? */
697 	ic = kzalloc(sizeof(struct rds_iw_connection), gfp);
698 	if (!ic)
699 		return -ENOMEM;
700 
701 	INIT_LIST_HEAD(&ic->iw_node);
702 	tasklet_init(&ic->i_recv_tasklet, rds_iw_recv_tasklet_fn,
703 		     (unsigned long) ic);
704 	mutex_init(&ic->i_recv_mutex);
705 #ifndef KERNEL_HAS_ATOMIC64
706 	spin_lock_init(&ic->i_ack_lock);
707 #endif
708 
709 	/*
710 	 * rds_iw_conn_shutdown() waits for these to be emptied so they
711 	 * must be initialized before it can be called.
712 	 */
713 	rds_iw_ring_init(&ic->i_send_ring, rds_iw_sysctl_max_send_wr);
714 	rds_iw_ring_init(&ic->i_recv_ring, rds_iw_sysctl_max_recv_wr);
715 
716 	ic->conn = conn;
717 	conn->c_transport_data = ic;
718 
719 	spin_lock_irqsave(&iw_nodev_conns_lock, flags);
720 	list_add_tail(&ic->iw_node, &iw_nodev_conns);
721 	spin_unlock_irqrestore(&iw_nodev_conns_lock, flags);
722 
723 
724 	rdsdebug("conn %p conn ic %p\n", conn, conn->c_transport_data);
725 	return 0;
726 }
727 
728 /*
729  * Free a connection. Connection must be shut down and not set for reconnect.
730  */
rds_iw_conn_free(void * arg)731 void rds_iw_conn_free(void *arg)
732 {
733 	struct rds_iw_connection *ic = arg;
734 	spinlock_t	*lock_ptr;
735 
736 	rdsdebug("ic %p\n", ic);
737 
738 	/*
739 	 * Conn is either on a dev's list or on the nodev list.
740 	 * A race with shutdown() or connect() would cause problems
741 	 * (since rds_iwdev would change) but that should never happen.
742 	 */
743 	lock_ptr = ic->rds_iwdev ? &ic->rds_iwdev->spinlock : &iw_nodev_conns_lock;
744 
745 	spin_lock_irq(lock_ptr);
746 	list_del(&ic->iw_node);
747 	spin_unlock_irq(lock_ptr);
748 
749 	kfree(ic);
750 }
751 
752 /*
753  * An error occurred on the connection
754  */
755 void
__rds_iw_conn_error(struct rds_connection * conn,const char * fmt,...)756 __rds_iw_conn_error(struct rds_connection *conn, const char *fmt, ...)
757 {
758 	va_list ap;
759 
760 	rds_conn_drop(conn);
761 
762 	va_start(ap, fmt);
763 	vprintk(fmt, ap);
764 	va_end(ap);
765 }
766