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v3.5.6
  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 "ib.h"
 41
 42static char *rds_ib_event_type_strings[] = {
 43#define RDS_IB_EVENT_STRING(foo) \
 44		[IB_EVENT_##foo] = __stringify(IB_EVENT_##foo)
 45	RDS_IB_EVENT_STRING(CQ_ERR),
 46	RDS_IB_EVENT_STRING(QP_FATAL),
 47	RDS_IB_EVENT_STRING(QP_REQ_ERR),
 48	RDS_IB_EVENT_STRING(QP_ACCESS_ERR),
 49	RDS_IB_EVENT_STRING(COMM_EST),
 50	RDS_IB_EVENT_STRING(SQ_DRAINED),
 51	RDS_IB_EVENT_STRING(PATH_MIG),
 52	RDS_IB_EVENT_STRING(PATH_MIG_ERR),
 53	RDS_IB_EVENT_STRING(DEVICE_FATAL),
 54	RDS_IB_EVENT_STRING(PORT_ACTIVE),
 55	RDS_IB_EVENT_STRING(PORT_ERR),
 56	RDS_IB_EVENT_STRING(LID_CHANGE),
 57	RDS_IB_EVENT_STRING(PKEY_CHANGE),
 58	RDS_IB_EVENT_STRING(SM_CHANGE),
 59	RDS_IB_EVENT_STRING(SRQ_ERR),
 60	RDS_IB_EVENT_STRING(SRQ_LIMIT_REACHED),
 61	RDS_IB_EVENT_STRING(QP_LAST_WQE_REACHED),
 62	RDS_IB_EVENT_STRING(CLIENT_REREGISTER),
 63#undef RDS_IB_EVENT_STRING
 64};
 65
 66static char *rds_ib_event_str(enum ib_event_type type)
 67{
 68	return rds_str_array(rds_ib_event_type_strings,
 69			     ARRAY_SIZE(rds_ib_event_type_strings), type);
 70};
 71
 72/*
 73 * Set the selected protocol version
 74 */
 75static void rds_ib_set_protocol(struct rds_connection *conn, unsigned int version)
 76{
 77	conn->c_version = version;
 78}
 79
 80/*
 81 * Set up flow control
 82 */
 83static void rds_ib_set_flow_control(struct rds_connection *conn, u32 credits)
 84{
 85	struct rds_ib_connection *ic = conn->c_transport_data;
 86
 87	if (rds_ib_sysctl_flow_control && credits != 0) {
 88		/* We're doing flow control */
 89		ic->i_flowctl = 1;
 90		rds_ib_send_add_credits(conn, credits);
 91	} else {
 92		ic->i_flowctl = 0;
 93	}
 94}
 95
 96/*
 97 * Tune RNR behavior. Without flow control, we use a rather
 98 * low timeout, but not the absolute minimum - this should
 99 * be tunable.
100 *
101 * We already set the RNR retry count to 7 (which is the
102 * smallest infinite number :-) above.
103 * If flow control is off, we want to change this back to 0
104 * so that we learn quickly when our credit accounting is
105 * buggy.
106 *
107 * Caller passes in a qp_attr pointer - don't waste stack spacv
108 * by allocation this twice.
109 */
110static void
111rds_ib_tune_rnr(struct rds_ib_connection *ic, struct ib_qp_attr *attr)
112{
113	int ret;
114
115	attr->min_rnr_timer = IB_RNR_TIMER_000_32;
116	ret = ib_modify_qp(ic->i_cm_id->qp, attr, IB_QP_MIN_RNR_TIMER);
117	if (ret)
118		printk(KERN_NOTICE "ib_modify_qp(IB_QP_MIN_RNR_TIMER): err=%d\n", -ret);
119}
120
121/*
122 * Connection established.
123 * We get here for both outgoing and incoming connection.
124 */
125void rds_ib_cm_connect_complete(struct rds_connection *conn, struct rdma_cm_event *event)
126{
127	const struct rds_ib_connect_private *dp = NULL;
128	struct rds_ib_connection *ic = conn->c_transport_data;
129	struct ib_qp_attr qp_attr;
130	int err;
131
132	if (event->param.conn.private_data_len >= sizeof(*dp)) {
133		dp = event->param.conn.private_data;
134
135		/* make sure it isn't empty data */
136		if (dp->dp_protocol_major) {
137			rds_ib_set_protocol(conn,
138				RDS_PROTOCOL(dp->dp_protocol_major,
139				dp->dp_protocol_minor));
140			rds_ib_set_flow_control(conn, be32_to_cpu(dp->dp_credit));
141		}
142	}
143
144	if (conn->c_version < RDS_PROTOCOL(3,1)) {
145		printk(KERN_NOTICE "RDS/IB: Connection to %pI4 version %u.%u failed,"
146		       " no longer supported\n",
147		       &conn->c_faddr,
148		       RDS_PROTOCOL_MAJOR(conn->c_version),
149		       RDS_PROTOCOL_MINOR(conn->c_version));
150		rds_conn_destroy(conn);
151		return;
152	} else {
153		printk(KERN_NOTICE "RDS/IB: connected to %pI4 version %u.%u%s\n",
154		       &conn->c_faddr,
155		       RDS_PROTOCOL_MAJOR(conn->c_version),
156		       RDS_PROTOCOL_MINOR(conn->c_version),
157		       ic->i_flowctl ? ", flow control" : "");
158	}
159
160	/*
161	 * Init rings and fill recv. this needs to wait until protocol negotiation
162	 * is complete, since ring layout is different from 3.0 to 3.1.
163	 */
164	rds_ib_send_init_ring(ic);
165	rds_ib_recv_init_ring(ic);
166	/* Post receive buffers - as a side effect, this will update
167	 * the posted credit count. */
168	rds_ib_recv_refill(conn, 1);
169
170	/* Tune RNR behavior */
171	rds_ib_tune_rnr(ic, &qp_attr);
172
173	qp_attr.qp_state = IB_QPS_RTS;
174	err = ib_modify_qp(ic->i_cm_id->qp, &qp_attr, IB_QP_STATE);
175	if (err)
176		printk(KERN_NOTICE "ib_modify_qp(IB_QP_STATE, RTS): err=%d\n", err);
177
178	/* update ib_device with this local ipaddr */
179	err = rds_ib_update_ipaddr(ic->rds_ibdev, conn->c_laddr);
180	if (err)
181		printk(KERN_ERR "rds_ib_update_ipaddr failed (%d)\n",
182			err);
183
184	/* If the peer gave us the last packet it saw, process this as if
185	 * we had received a regular ACK. */
186	if (dp && dp->dp_ack_seq)
187		rds_send_drop_acked(conn, be64_to_cpu(dp->dp_ack_seq), NULL);
 
 
 
 
 
 
 
 
 
188
189	rds_connect_complete(conn);
190}
191
192static void rds_ib_cm_fill_conn_param(struct rds_connection *conn,
193			struct rdma_conn_param *conn_param,
194			struct rds_ib_connect_private *dp,
195			u32 protocol_version,
196			u32 max_responder_resources,
197			u32 max_initiator_depth)
198{
199	struct rds_ib_connection *ic = conn->c_transport_data;
200	struct rds_ib_device *rds_ibdev = ic->rds_ibdev;
201
202	memset(conn_param, 0, sizeof(struct rdma_conn_param));
203
204	conn_param->responder_resources =
205		min_t(u32, rds_ibdev->max_responder_resources, max_responder_resources);
206	conn_param->initiator_depth =
207		min_t(u32, rds_ibdev->max_initiator_depth, max_initiator_depth);
208	conn_param->retry_count = min_t(unsigned int, rds_ib_retry_count, 7);
209	conn_param->rnr_retry_count = 7;
210
211	if (dp) {
212		memset(dp, 0, sizeof(*dp));
213		dp->dp_saddr = conn->c_laddr;
214		dp->dp_daddr = conn->c_faddr;
215		dp->dp_protocol_major = RDS_PROTOCOL_MAJOR(protocol_version);
216		dp->dp_protocol_minor = RDS_PROTOCOL_MINOR(protocol_version);
217		dp->dp_protocol_minor_mask = cpu_to_be16(RDS_IB_SUPPORTED_PROTOCOLS);
218		dp->dp_ack_seq = rds_ib_piggyb_ack(ic);
219
220		/* Advertise flow control */
221		if (ic->i_flowctl) {
222			unsigned int credits;
223
224			credits = IB_GET_POST_CREDITS(atomic_read(&ic->i_credits));
225			dp->dp_credit = cpu_to_be32(credits);
226			atomic_sub(IB_SET_POST_CREDITS(credits), &ic->i_credits);
227		}
228
229		conn_param->private_data = dp;
230		conn_param->private_data_len = sizeof(*dp);
231	}
232}
233
234static void rds_ib_cq_event_handler(struct ib_event *event, void *data)
235{
236	rdsdebug("event %u (%s) data %p\n",
237		 event->event, rds_ib_event_str(event->event), data);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
238}
239
240static void rds_ib_qp_event_handler(struct ib_event *event, void *data)
241{
242	struct rds_connection *conn = data;
243	struct rds_ib_connection *ic = conn->c_transport_data;
244
245	rdsdebug("conn %p ic %p event %u (%s)\n", conn, ic, event->event,
246		 rds_ib_event_str(event->event));
247
248	switch (event->event) {
249	case IB_EVENT_COMM_EST:
250		rdma_notify(ic->i_cm_id, IB_EVENT_COMM_EST);
251		break;
252	default:
253		rdsdebug("Fatal QP Event %u (%s) "
254			"- connection %pI4->%pI4, reconnecting\n",
255			event->event, rds_ib_event_str(event->event),
256			&conn->c_laddr, &conn->c_faddr);
257		rds_conn_drop(conn);
258		break;
259	}
260}
261
 
 
 
 
 
 
 
 
 
 
 
 
262/*
263 * This needs to be very careful to not leave IS_ERR pointers around for
264 * cleanup to trip over.
265 */
266static int rds_ib_setup_qp(struct rds_connection *conn)
267{
268	struct rds_ib_connection *ic = conn->c_transport_data;
269	struct ib_device *dev = ic->i_cm_id->device;
270	struct ib_qp_init_attr attr;
 
271	struct rds_ib_device *rds_ibdev;
272	int ret;
273
274	/*
275	 * It's normal to see a null device if an incoming connection races
276	 * with device removal, so we don't print a warning.
277	 */
278	rds_ibdev = rds_ib_get_client_data(dev);
279	if (!rds_ibdev)
280		return -EOPNOTSUPP;
281
 
 
 
 
 
 
282	/* add the conn now so that connection establishment has the dev */
283	rds_ib_add_conn(rds_ibdev, conn);
284
285	if (rds_ibdev->max_wrs < ic->i_send_ring.w_nr + 1)
286		rds_ib_ring_resize(&ic->i_send_ring, rds_ibdev->max_wrs - 1);
287	if (rds_ibdev->max_wrs < ic->i_recv_ring.w_nr + 1)
288		rds_ib_ring_resize(&ic->i_recv_ring, rds_ibdev->max_wrs - 1);
289
290	/* Protection domain and memory range */
291	ic->i_pd = rds_ibdev->pd;
292	ic->i_mr = rds_ibdev->mr;
293
294	ic->i_send_cq = ib_create_cq(dev, rds_ib_send_cq_comp_handler,
 
 
295				     rds_ib_cq_event_handler, conn,
296				     ic->i_send_ring.w_nr + 1, 0);
297	if (IS_ERR(ic->i_send_cq)) {
298		ret = PTR_ERR(ic->i_send_cq);
299		ic->i_send_cq = NULL;
300		rdsdebug("ib_create_cq send failed: %d\n", ret);
301		goto out;
302	}
303
304	ic->i_recv_cq = ib_create_cq(dev, rds_ib_recv_cq_comp_handler,
 
305				     rds_ib_cq_event_handler, conn,
306				     ic->i_recv_ring.w_nr, 0);
307	if (IS_ERR(ic->i_recv_cq)) {
308		ret = PTR_ERR(ic->i_recv_cq);
309		ic->i_recv_cq = NULL;
310		rdsdebug("ib_create_cq recv failed: %d\n", ret);
311		goto out;
312	}
313
314	ret = ib_req_notify_cq(ic->i_send_cq, IB_CQ_NEXT_COMP);
315	if (ret) {
316		rdsdebug("ib_req_notify_cq send failed: %d\n", ret);
317		goto out;
318	}
319
320	ret = ib_req_notify_cq(ic->i_recv_cq, IB_CQ_SOLICITED);
321	if (ret) {
322		rdsdebug("ib_req_notify_cq recv failed: %d\n", ret);
323		goto out;
324	}
325
326	/* XXX negotiate max send/recv with remote? */
327	memset(&attr, 0, sizeof(attr));
328	attr.event_handler = rds_ib_qp_event_handler;
329	attr.qp_context = conn;
330	/* + 1 to allow for the single ack message */
331	attr.cap.max_send_wr = ic->i_send_ring.w_nr + 1;
332	attr.cap.max_recv_wr = ic->i_recv_ring.w_nr + 1;
333	attr.cap.max_send_sge = rds_ibdev->max_sge;
334	attr.cap.max_recv_sge = RDS_IB_RECV_SGE;
335	attr.sq_sig_type = IB_SIGNAL_REQ_WR;
336	attr.qp_type = IB_QPT_RC;
337	attr.send_cq = ic->i_send_cq;
338	attr.recv_cq = ic->i_recv_cq;
 
339
340	/*
341	 * XXX this can fail if max_*_wr is too large?  Are we supposed
342	 * to back off until we get a value that the hardware can support?
343	 */
344	ret = rdma_create_qp(ic->i_cm_id, ic->i_pd, &attr);
345	if (ret) {
346		rdsdebug("rdma_create_qp failed: %d\n", ret);
347		goto out;
348	}
349
350	ic->i_send_hdrs = ib_dma_alloc_coherent(dev,
351					   ic->i_send_ring.w_nr *
352						sizeof(struct rds_header),
353					   &ic->i_send_hdrs_dma, GFP_KERNEL);
354	if (!ic->i_send_hdrs) {
355		ret = -ENOMEM;
356		rdsdebug("ib_dma_alloc_coherent send failed\n");
357		goto out;
358	}
359
360	ic->i_recv_hdrs = ib_dma_alloc_coherent(dev,
361					   ic->i_recv_ring.w_nr *
362						sizeof(struct rds_header),
363					   &ic->i_recv_hdrs_dma, GFP_KERNEL);
364	if (!ic->i_recv_hdrs) {
365		ret = -ENOMEM;
366		rdsdebug("ib_dma_alloc_coherent recv failed\n");
367		goto out;
368	}
369
370	ic->i_ack = ib_dma_alloc_coherent(dev, sizeof(struct rds_header),
371				       &ic->i_ack_dma, GFP_KERNEL);
372	if (!ic->i_ack) {
373		ret = -ENOMEM;
374		rdsdebug("ib_dma_alloc_coherent ack failed\n");
375		goto out;
376	}
377
378	ic->i_sends = vzalloc_node(ic->i_send_ring.w_nr * sizeof(struct rds_ib_send_work),
379				   ibdev_to_node(dev));
380	if (!ic->i_sends) {
381		ret = -ENOMEM;
382		rdsdebug("send allocation failed\n");
383		goto out;
384	}
385
386	ic->i_recvs = vzalloc_node(ic->i_recv_ring.w_nr * sizeof(struct rds_ib_recv_work),
387				   ibdev_to_node(dev));
388	if (!ic->i_recvs) {
389		ret = -ENOMEM;
390		rdsdebug("recv allocation failed\n");
391		goto out;
392	}
393
394	rds_ib_recv_init_ack(ic);
395
396	rdsdebug("conn %p pd %p mr %p cq %p %p\n", conn, ic->i_pd, ic->i_mr,
397		 ic->i_send_cq, ic->i_recv_cq);
398
399out:
400	rds_ib_dev_put(rds_ibdev);
401	return ret;
402}
403
404static u32 rds_ib_protocol_compatible(struct rdma_cm_event *event)
405{
406	const struct rds_ib_connect_private *dp = event->param.conn.private_data;
407	u16 common;
408	u32 version = 0;
409
410	/*
411	 * rdma_cm private data is odd - when there is any private data in the
412	 * request, we will be given a pretty large buffer without telling us the
413	 * original size. The only way to tell the difference is by looking at
414	 * the contents, which are initialized to zero.
415	 * If the protocol version fields aren't set, this is a connection attempt
416	 * from an older version. This could could be 3.0 or 2.0 - we can't tell.
417	 * We really should have changed this for OFED 1.3 :-(
418	 */
419
420	/* Be paranoid. RDS always has privdata */
421	if (!event->param.conn.private_data_len) {
422		printk(KERN_NOTICE "RDS incoming connection has no private data, "
423			"rejecting\n");
424		return 0;
425	}
426
427	/* Even if len is crap *now* I still want to check it. -ASG */
428	if (event->param.conn.private_data_len < sizeof (*dp) ||
429	    dp->dp_protocol_major == 0)
430		return RDS_PROTOCOL_3_0;
431
432	common = be16_to_cpu(dp->dp_protocol_minor_mask) & RDS_IB_SUPPORTED_PROTOCOLS;
433	if (dp->dp_protocol_major == 3 && common) {
434		version = RDS_PROTOCOL_3_0;
435		while ((common >>= 1) != 0)
436			version++;
437	}
438	printk_ratelimited(KERN_NOTICE "RDS: Connection from %pI4 using "
439			"incompatible protocol version %u.%u\n",
440			&dp->dp_saddr,
441			dp->dp_protocol_major,
442			dp->dp_protocol_minor);
443	return version;
444}
445
446int rds_ib_cm_handle_connect(struct rdma_cm_id *cm_id,
447				    struct rdma_cm_event *event)
448{
449	__be64 lguid = cm_id->route.path_rec->sgid.global.interface_id;
450	__be64 fguid = cm_id->route.path_rec->dgid.global.interface_id;
451	const struct rds_ib_connect_private *dp = event->param.conn.private_data;
452	struct rds_ib_connect_private dp_rep;
453	struct rds_connection *conn = NULL;
454	struct rds_ib_connection *ic = NULL;
455	struct rdma_conn_param conn_param;
456	u32 version;
457	int err = 1, destroy = 1;
458
459	/* Check whether the remote protocol version matches ours. */
460	version = rds_ib_protocol_compatible(event);
461	if (!version)
462		goto out;
463
464	rdsdebug("saddr %pI4 daddr %pI4 RDSv%u.%u lguid 0x%llx fguid "
465		 "0x%llx\n", &dp->dp_saddr, &dp->dp_daddr,
466		 RDS_PROTOCOL_MAJOR(version), RDS_PROTOCOL_MINOR(version),
467		 (unsigned long long)be64_to_cpu(lguid),
468		 (unsigned long long)be64_to_cpu(fguid));
469
470	conn = rds_conn_create(dp->dp_daddr, dp->dp_saddr, &rds_ib_transport,
471			       GFP_KERNEL);
 
472	if (IS_ERR(conn)) {
473		rdsdebug("rds_conn_create failed (%ld)\n", PTR_ERR(conn));
474		conn = NULL;
475		goto out;
476	}
477
478	/*
479	 * The connection request may occur while the
480	 * previous connection exist, e.g. in case of failover.
481	 * But as connections may be initiated simultaneously
482	 * by both hosts, we have a random backoff mechanism -
483	 * see the comment above rds_queue_reconnect()
484	 */
485	mutex_lock(&conn->c_cm_lock);
486	if (!rds_conn_transition(conn, RDS_CONN_DOWN, RDS_CONN_CONNECTING)) {
487		if (rds_conn_state(conn) == RDS_CONN_UP) {
488			rdsdebug("incoming connect while connecting\n");
489			rds_conn_drop(conn);
490			rds_ib_stats_inc(s_ib_listen_closed_stale);
491		} else
492		if (rds_conn_state(conn) == RDS_CONN_CONNECTING) {
493			/* Wait and see - our connect may still be succeeding */
494			rds_ib_stats_inc(s_ib_connect_raced);
495		}
496		goto out;
497	}
498
499	ic = conn->c_transport_data;
500
501	rds_ib_set_protocol(conn, version);
502	rds_ib_set_flow_control(conn, be32_to_cpu(dp->dp_credit));
503
504	/* If the peer gave us the last packet it saw, process this as if
505	 * we had received a regular ACK. */
506	if (dp->dp_ack_seq)
507		rds_send_drop_acked(conn, be64_to_cpu(dp->dp_ack_seq), NULL);
508
509	BUG_ON(cm_id->context);
510	BUG_ON(ic->i_cm_id);
511
512	ic->i_cm_id = cm_id;
513	cm_id->context = conn;
514
515	/* We got halfway through setting up the ib_connection, if we
516	 * fail now, we have to take the long route out of this mess. */
517	destroy = 0;
518
519	err = rds_ib_setup_qp(conn);
520	if (err) {
521		rds_ib_conn_error(conn, "rds_ib_setup_qp failed (%d)\n", err);
522		goto out;
523	}
524
525	rds_ib_cm_fill_conn_param(conn, &conn_param, &dp_rep, version,
526		event->param.conn.responder_resources,
527		event->param.conn.initiator_depth);
528
529	/* rdma_accept() calls rdma_reject() internally if it fails */
530	err = rdma_accept(cm_id, &conn_param);
531	if (err)
532		rds_ib_conn_error(conn, "rdma_accept failed (%d)\n", err);
533
534out:
535	if (conn)
536		mutex_unlock(&conn->c_cm_lock);
537	if (err)
538		rdma_reject(cm_id, NULL, 0);
539	return destroy;
540}
541
542
543int rds_ib_cm_initiate_connect(struct rdma_cm_id *cm_id)
544{
545	struct rds_connection *conn = cm_id->context;
546	struct rds_ib_connection *ic = conn->c_transport_data;
547	struct rdma_conn_param conn_param;
548	struct rds_ib_connect_private dp;
549	int ret;
550
551	/* If the peer doesn't do protocol negotiation, we must
552	 * default to RDSv3.0 */
553	rds_ib_set_protocol(conn, RDS_PROTOCOL_3_0);
554	ic->i_flowctl = rds_ib_sysctl_flow_control;	/* advertise flow control */
555
556	ret = rds_ib_setup_qp(conn);
557	if (ret) {
558		rds_ib_conn_error(conn, "rds_ib_setup_qp failed (%d)\n", ret);
559		goto out;
560	}
561
562	rds_ib_cm_fill_conn_param(conn, &conn_param, &dp, RDS_PROTOCOL_VERSION,
563		UINT_MAX, UINT_MAX);
564	ret = rdma_connect(cm_id, &conn_param);
565	if (ret)
566		rds_ib_conn_error(conn, "rdma_connect failed (%d)\n", ret);
567
568out:
569	/* Beware - returning non-zero tells the rdma_cm to destroy
570	 * the cm_id. We should certainly not do it as long as we still
571	 * "own" the cm_id. */
572	if (ret) {
573		if (ic->i_cm_id == cm_id)
574			ret = 0;
575	}
576	return ret;
577}
578
579int rds_ib_conn_connect(struct rds_connection *conn)
580{
 
581	struct rds_ib_connection *ic = conn->c_transport_data;
582	struct sockaddr_in src, dest;
583	int ret;
584
585	/* XXX I wonder what affect the port space has */
586	/* delegate cm event handler to rdma_transport */
587	ic->i_cm_id = rdma_create_id(rds_rdma_cm_event_handler, conn,
588				     RDMA_PS_TCP, IB_QPT_RC);
589	if (IS_ERR(ic->i_cm_id)) {
590		ret = PTR_ERR(ic->i_cm_id);
591		ic->i_cm_id = NULL;
592		rdsdebug("rdma_create_id() failed: %d\n", ret);
593		goto out;
594	}
595
596	rdsdebug("created cm id %p for conn %p\n", ic->i_cm_id, conn);
597
598	src.sin_family = AF_INET;
599	src.sin_addr.s_addr = (__force u32)conn->c_laddr;
600	src.sin_port = (__force u16)htons(0);
601
602	dest.sin_family = AF_INET;
603	dest.sin_addr.s_addr = (__force u32)conn->c_faddr;
604	dest.sin_port = (__force u16)htons(RDS_PORT);
605
606	ret = rdma_resolve_addr(ic->i_cm_id, (struct sockaddr *)&src,
607				(struct sockaddr *)&dest,
608				RDS_RDMA_RESOLVE_TIMEOUT_MS);
609	if (ret) {
610		rdsdebug("addr resolve failed for cm id %p: %d\n", ic->i_cm_id,
611			 ret);
612		rdma_destroy_id(ic->i_cm_id);
613		ic->i_cm_id = NULL;
614	}
615
616out:
617	return ret;
618}
619
620/*
621 * This is so careful about only cleaning up resources that were built up
622 * so that it can be called at any point during startup.  In fact it
623 * can be called multiple times for a given connection.
624 */
625void rds_ib_conn_shutdown(struct rds_connection *conn)
626{
 
627	struct rds_ib_connection *ic = conn->c_transport_data;
628	int err = 0;
629
630	rdsdebug("cm %p pd %p cq %p %p qp %p\n", ic->i_cm_id,
631		 ic->i_pd, ic->i_send_cq, ic->i_recv_cq,
632		 ic->i_cm_id ? ic->i_cm_id->qp : NULL);
633
634	if (ic->i_cm_id) {
635		struct ib_device *dev = ic->i_cm_id->device;
636
637		rdsdebug("disconnecting cm %p\n", ic->i_cm_id);
638		err = rdma_disconnect(ic->i_cm_id);
639		if (err) {
640			/* Actually this may happen quite frequently, when
641			 * an outgoing connect raced with an incoming connect.
642			 */
643			rdsdebug("failed to disconnect, cm: %p err %d\n",
644				ic->i_cm_id, err);
645		}
646
647		/*
648		 * We want to wait for tx and rx completion to finish
649		 * before we tear down the connection, but we have to be
650		 * careful not to get stuck waiting on a send ring that
651		 * only has unsignaled sends in it.  We've shutdown new
652		 * sends before getting here so by waiting for signaled
653		 * sends to complete we're ensured that there will be no
654		 * more tx processing.
655		 */
656		wait_event(rds_ib_ring_empty_wait,
657			   rds_ib_ring_empty(&ic->i_recv_ring) &&
658			   (atomic_read(&ic->i_signaled_sends) == 0));
 
 
659		tasklet_kill(&ic->i_recv_tasklet);
660
 
 
 
 
 
 
 
 
 
661		if (ic->i_send_hdrs)
662			ib_dma_free_coherent(dev,
663					   ic->i_send_ring.w_nr *
664						sizeof(struct rds_header),
665					   ic->i_send_hdrs,
666					   ic->i_send_hdrs_dma);
667
668		if (ic->i_recv_hdrs)
669			ib_dma_free_coherent(dev,
670					   ic->i_recv_ring.w_nr *
671						sizeof(struct rds_header),
672					   ic->i_recv_hdrs,
673					   ic->i_recv_hdrs_dma);
674
675		if (ic->i_ack)
676			ib_dma_free_coherent(dev, sizeof(struct rds_header),
677					     ic->i_ack, ic->i_ack_dma);
678
679		if (ic->i_sends)
680			rds_ib_send_clear_ring(ic);
681		if (ic->i_recvs)
682			rds_ib_recv_clear_ring(ic);
683
684		if (ic->i_cm_id->qp)
685			rdma_destroy_qp(ic->i_cm_id);
686		if (ic->i_send_cq)
687			ib_destroy_cq(ic->i_send_cq);
688		if (ic->i_recv_cq)
689			ib_destroy_cq(ic->i_recv_cq);
690		rdma_destroy_id(ic->i_cm_id);
691
692		/*
693		 * Move connection back to the nodev list.
694		 */
695		if (ic->rds_ibdev)
696			rds_ib_remove_conn(ic->rds_ibdev, conn);
697
698		ic->i_cm_id = NULL;
699		ic->i_pd = NULL;
700		ic->i_mr = NULL;
701		ic->i_send_cq = NULL;
702		ic->i_recv_cq = NULL;
703		ic->i_send_hdrs = NULL;
704		ic->i_recv_hdrs = NULL;
705		ic->i_ack = NULL;
706	}
707	BUG_ON(ic->rds_ibdev);
708
709	/* Clear pending transmit */
710	if (ic->i_data_op) {
711		struct rds_message *rm;
712
713		rm = container_of(ic->i_data_op, struct rds_message, data);
714		rds_message_put(rm);
715		ic->i_data_op = NULL;
716	}
717
718	/* Clear the ACK state */
719	clear_bit(IB_ACK_IN_FLIGHT, &ic->i_ack_flags);
720#ifdef KERNEL_HAS_ATOMIC64
721	atomic64_set(&ic->i_ack_next, 0);
722#else
723	ic->i_ack_next = 0;
724#endif
725	ic->i_ack_recv = 0;
726
727	/* Clear flow control state */
728	ic->i_flowctl = 0;
729	atomic_set(&ic->i_credits, 0);
730
731	rds_ib_ring_init(&ic->i_send_ring, rds_ib_sysctl_max_send_wr);
732	rds_ib_ring_init(&ic->i_recv_ring, rds_ib_sysctl_max_recv_wr);
733
734	if (ic->i_ibinc) {
735		rds_inc_put(&ic->i_ibinc->ii_inc);
736		ic->i_ibinc = NULL;
737	}
738
739	vfree(ic->i_sends);
740	ic->i_sends = NULL;
741	vfree(ic->i_recvs);
742	ic->i_recvs = NULL;
743}
744
745int rds_ib_conn_alloc(struct rds_connection *conn, gfp_t gfp)
746{
747	struct rds_ib_connection *ic;
748	unsigned long flags;
749	int ret;
750
751	/* XXX too lazy? */
752	ic = kzalloc(sizeof(struct rds_ib_connection), gfp);
753	if (!ic)
754		return -ENOMEM;
755
756	ret = rds_ib_recv_alloc_caches(ic);
757	if (ret) {
758		kfree(ic);
759		return ret;
760	}
761
762	INIT_LIST_HEAD(&ic->ib_node);
763	tasklet_init(&ic->i_recv_tasklet, rds_ib_recv_tasklet_fn,
764		     (unsigned long) ic);
 
 
765	mutex_init(&ic->i_recv_mutex);
766#ifndef KERNEL_HAS_ATOMIC64
767	spin_lock_init(&ic->i_ack_lock);
768#endif
769	atomic_set(&ic->i_signaled_sends, 0);
770
771	/*
772	 * rds_ib_conn_shutdown() waits for these to be emptied so they
773	 * must be initialized before it can be called.
774	 */
775	rds_ib_ring_init(&ic->i_send_ring, rds_ib_sysctl_max_send_wr);
776	rds_ib_ring_init(&ic->i_recv_ring, rds_ib_sysctl_max_recv_wr);
777
778	ic->conn = conn;
779	conn->c_transport_data = ic;
780
781	spin_lock_irqsave(&ib_nodev_conns_lock, flags);
782	list_add_tail(&ic->ib_node, &ib_nodev_conns);
783	spin_unlock_irqrestore(&ib_nodev_conns_lock, flags);
784
785
786	rdsdebug("conn %p conn ic %p\n", conn, conn->c_transport_data);
787	return 0;
788}
789
790/*
791 * Free a connection. Connection must be shut down and not set for reconnect.
792 */
793void rds_ib_conn_free(void *arg)
794{
795	struct rds_ib_connection *ic = arg;
796	spinlock_t	*lock_ptr;
797
798	rdsdebug("ic %p\n", ic);
799
800	/*
801	 * Conn is either on a dev's list or on the nodev list.
802	 * A race with shutdown() or connect() would cause problems
803	 * (since rds_ibdev would change) but that should never happen.
804	 */
805	lock_ptr = ic->rds_ibdev ? &ic->rds_ibdev->spinlock : &ib_nodev_conns_lock;
806
807	spin_lock_irq(lock_ptr);
808	list_del(&ic->ib_node);
809	spin_unlock_irq(lock_ptr);
810
811	rds_ib_recv_free_caches(ic);
812
813	kfree(ic);
814}
815
816
817/*
818 * An error occurred on the connection
819 */
820void
821__rds_ib_conn_error(struct rds_connection *conn, const char *fmt, ...)
822{
823	va_list ap;
824
825	rds_conn_drop(conn);
826
827	va_start(ap, fmt);
828	vprintk(fmt, ap);
829	va_end(ap);
830}
v4.10.11
  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_single_path.h"
 40#include "rds.h"
 41#include "ib.h"
 42
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 43/*
 44 * Set the selected protocol version
 45 */
 46static void rds_ib_set_protocol(struct rds_connection *conn, unsigned int version)
 47{
 48	conn->c_version = version;
 49}
 50
 51/*
 52 * Set up flow control
 53 */
 54static void rds_ib_set_flow_control(struct rds_connection *conn, u32 credits)
 55{
 56	struct rds_ib_connection *ic = conn->c_transport_data;
 57
 58	if (rds_ib_sysctl_flow_control && credits != 0) {
 59		/* We're doing flow control */
 60		ic->i_flowctl = 1;
 61		rds_ib_send_add_credits(conn, credits);
 62	} else {
 63		ic->i_flowctl = 0;
 64	}
 65}
 66
 67/*
 68 * Tune RNR behavior. Without flow control, we use a rather
 69 * low timeout, but not the absolute minimum - this should
 70 * be tunable.
 71 *
 72 * We already set the RNR retry count to 7 (which is the
 73 * smallest infinite number :-) above.
 74 * If flow control is off, we want to change this back to 0
 75 * so that we learn quickly when our credit accounting is
 76 * buggy.
 77 *
 78 * Caller passes in a qp_attr pointer - don't waste stack spacv
 79 * by allocation this twice.
 80 */
 81static void
 82rds_ib_tune_rnr(struct rds_ib_connection *ic, struct ib_qp_attr *attr)
 83{
 84	int ret;
 85
 86	attr->min_rnr_timer = IB_RNR_TIMER_000_32;
 87	ret = ib_modify_qp(ic->i_cm_id->qp, attr, IB_QP_MIN_RNR_TIMER);
 88	if (ret)
 89		printk(KERN_NOTICE "ib_modify_qp(IB_QP_MIN_RNR_TIMER): err=%d\n", -ret);
 90}
 91
 92/*
 93 * Connection established.
 94 * We get here for both outgoing and incoming connection.
 95 */
 96void rds_ib_cm_connect_complete(struct rds_connection *conn, struct rdma_cm_event *event)
 97{
 98	const struct rds_ib_connect_private *dp = NULL;
 99	struct rds_ib_connection *ic = conn->c_transport_data;
100	struct ib_qp_attr qp_attr;
101	int err;
102
103	if (event->param.conn.private_data_len >= sizeof(*dp)) {
104		dp = event->param.conn.private_data;
105
106		/* make sure it isn't empty data */
107		if (dp->dp_protocol_major) {
108			rds_ib_set_protocol(conn,
109				RDS_PROTOCOL(dp->dp_protocol_major,
110				dp->dp_protocol_minor));
111			rds_ib_set_flow_control(conn, be32_to_cpu(dp->dp_credit));
112		}
113	}
114
115	if (conn->c_version < RDS_PROTOCOL(3, 1)) {
116		printk(KERN_NOTICE "RDS/IB: Connection to %pI4 version %u.%u failed,"
117		       " no longer supported\n",
118		       &conn->c_faddr,
119		       RDS_PROTOCOL_MAJOR(conn->c_version),
120		       RDS_PROTOCOL_MINOR(conn->c_version));
121		rds_conn_destroy(conn);
122		return;
123	} else {
124		printk(KERN_NOTICE "RDS/IB: connected to %pI4 version %u.%u%s\n",
125		       &conn->c_faddr,
126		       RDS_PROTOCOL_MAJOR(conn->c_version),
127		       RDS_PROTOCOL_MINOR(conn->c_version),
128		       ic->i_flowctl ? ", flow control" : "");
129	}
130
131	/*
132	 * Init rings and fill recv. this needs to wait until protocol negotiation
133	 * is complete, since ring layout is different from 3.0 to 3.1.
134	 */
135	rds_ib_send_init_ring(ic);
136	rds_ib_recv_init_ring(ic);
137	/* Post receive buffers - as a side effect, this will update
138	 * the posted credit count. */
139	rds_ib_recv_refill(conn, 1, GFP_KERNEL);
140
141	/* Tune RNR behavior */
142	rds_ib_tune_rnr(ic, &qp_attr);
143
144	qp_attr.qp_state = IB_QPS_RTS;
145	err = ib_modify_qp(ic->i_cm_id->qp, &qp_attr, IB_QP_STATE);
146	if (err)
147		printk(KERN_NOTICE "ib_modify_qp(IB_QP_STATE, RTS): err=%d\n", err);
148
149	/* update ib_device with this local ipaddr */
150	err = rds_ib_update_ipaddr(ic->rds_ibdev, conn->c_laddr);
151	if (err)
152		printk(KERN_ERR "rds_ib_update_ipaddr failed (%d)\n",
153			err);
154
155	/* If the peer gave us the last packet it saw, process this as if
156	 * we had received a regular ACK. */
157	if (dp) {
158		/* dp structure start is not guaranteed to be 8 bytes aligned.
159		 * Since dp_ack_seq is 64-bit extended load operations can be
160		 * used so go through get_unaligned to avoid unaligned errors.
161		 */
162		__be64 dp_ack_seq = get_unaligned(&dp->dp_ack_seq);
163
164		if (dp_ack_seq)
165			rds_send_drop_acked(conn, be64_to_cpu(dp_ack_seq),
166					    NULL);
167	}
168
169	rds_connect_complete(conn);
170}
171
172static void rds_ib_cm_fill_conn_param(struct rds_connection *conn,
173			struct rdma_conn_param *conn_param,
174			struct rds_ib_connect_private *dp,
175			u32 protocol_version,
176			u32 max_responder_resources,
177			u32 max_initiator_depth)
178{
179	struct rds_ib_connection *ic = conn->c_transport_data;
180	struct rds_ib_device *rds_ibdev = ic->rds_ibdev;
181
182	memset(conn_param, 0, sizeof(struct rdma_conn_param));
183
184	conn_param->responder_resources =
185		min_t(u32, rds_ibdev->max_responder_resources, max_responder_resources);
186	conn_param->initiator_depth =
187		min_t(u32, rds_ibdev->max_initiator_depth, max_initiator_depth);
188	conn_param->retry_count = min_t(unsigned int, rds_ib_retry_count, 7);
189	conn_param->rnr_retry_count = 7;
190
191	if (dp) {
192		memset(dp, 0, sizeof(*dp));
193		dp->dp_saddr = conn->c_laddr;
194		dp->dp_daddr = conn->c_faddr;
195		dp->dp_protocol_major = RDS_PROTOCOL_MAJOR(protocol_version);
196		dp->dp_protocol_minor = RDS_PROTOCOL_MINOR(protocol_version);
197		dp->dp_protocol_minor_mask = cpu_to_be16(RDS_IB_SUPPORTED_PROTOCOLS);
198		dp->dp_ack_seq = cpu_to_be64(rds_ib_piggyb_ack(ic));
199
200		/* Advertise flow control */
201		if (ic->i_flowctl) {
202			unsigned int credits;
203
204			credits = IB_GET_POST_CREDITS(atomic_read(&ic->i_credits));
205			dp->dp_credit = cpu_to_be32(credits);
206			atomic_sub(IB_SET_POST_CREDITS(credits), &ic->i_credits);
207		}
208
209		conn_param->private_data = dp;
210		conn_param->private_data_len = sizeof(*dp);
211	}
212}
213
214static void rds_ib_cq_event_handler(struct ib_event *event, void *data)
215{
216	rdsdebug("event %u (%s) data %p\n",
217		 event->event, ib_event_msg(event->event), data);
218}
219
220/* Plucking the oldest entry from the ring can be done concurrently with
221 * the thread refilling the ring.  Each ring operation is protected by
222 * spinlocks and the transient state of refilling doesn't change the
223 * recording of which entry is oldest.
224 *
225 * This relies on IB only calling one cq comp_handler for each cq so that
226 * there will only be one caller of rds_recv_incoming() per RDS connection.
227 */
228static void rds_ib_cq_comp_handler_recv(struct ib_cq *cq, void *context)
229{
230	struct rds_connection *conn = context;
231	struct rds_ib_connection *ic = conn->c_transport_data;
232
233	rdsdebug("conn %p cq %p\n", conn, cq);
234
235	rds_ib_stats_inc(s_ib_evt_handler_call);
236
237	tasklet_schedule(&ic->i_recv_tasklet);
238}
239
240static void poll_scq(struct rds_ib_connection *ic, struct ib_cq *cq,
241		     struct ib_wc *wcs)
242{
243	int nr, i;
244	struct ib_wc *wc;
245
246	while ((nr = ib_poll_cq(cq, RDS_IB_WC_MAX, wcs)) > 0) {
247		for (i = 0; i < nr; i++) {
248			wc = wcs + i;
249			rdsdebug("wc wr_id 0x%llx status %u byte_len %u imm_data %u\n",
250				 (unsigned long long)wc->wr_id, wc->status,
251				 wc->byte_len, be32_to_cpu(wc->ex.imm_data));
252
253			if (wc->wr_id <= ic->i_send_ring.w_nr ||
254			    wc->wr_id == RDS_IB_ACK_WR_ID)
255				rds_ib_send_cqe_handler(ic, wc);
256			else
257				rds_ib_mr_cqe_handler(ic, wc);
258
259		}
260	}
261}
262
263static void rds_ib_tasklet_fn_send(unsigned long data)
264{
265	struct rds_ib_connection *ic = (struct rds_ib_connection *)data;
266	struct rds_connection *conn = ic->conn;
267
268	rds_ib_stats_inc(s_ib_tasklet_call);
269
270	poll_scq(ic, ic->i_send_cq, ic->i_send_wc);
271	ib_req_notify_cq(ic->i_send_cq, IB_CQ_NEXT_COMP);
272	poll_scq(ic, ic->i_send_cq, ic->i_send_wc);
273
274	if (rds_conn_up(conn) &&
275	    (!test_bit(RDS_LL_SEND_FULL, &conn->c_flags) ||
276	    test_bit(0, &conn->c_map_queued)))
277		rds_send_xmit(&ic->conn->c_path[0]);
278}
279
280static void poll_rcq(struct rds_ib_connection *ic, struct ib_cq *cq,
281		     struct ib_wc *wcs,
282		     struct rds_ib_ack_state *ack_state)
283{
284	int nr, i;
285	struct ib_wc *wc;
286
287	while ((nr = ib_poll_cq(cq, RDS_IB_WC_MAX, wcs)) > 0) {
288		for (i = 0; i < nr; i++) {
289			wc = wcs + i;
290			rdsdebug("wc wr_id 0x%llx status %u byte_len %u imm_data %u\n",
291				 (unsigned long long)wc->wr_id, wc->status,
292				 wc->byte_len, be32_to_cpu(wc->ex.imm_data));
293
294			rds_ib_recv_cqe_handler(ic, wc, ack_state);
295		}
296	}
297}
298
299static void rds_ib_tasklet_fn_recv(unsigned long data)
300{
301	struct rds_ib_connection *ic = (struct rds_ib_connection *)data;
302	struct rds_connection *conn = ic->conn;
303	struct rds_ib_device *rds_ibdev = ic->rds_ibdev;
304	struct rds_ib_ack_state state;
305
306	if (!rds_ibdev)
307		rds_conn_drop(conn);
308
309	rds_ib_stats_inc(s_ib_tasklet_call);
310
311	memset(&state, 0, sizeof(state));
312	poll_rcq(ic, ic->i_recv_cq, ic->i_recv_wc, &state);
313	ib_req_notify_cq(ic->i_recv_cq, IB_CQ_SOLICITED);
314	poll_rcq(ic, ic->i_recv_cq, ic->i_recv_wc, &state);
315
316	if (state.ack_next_valid)
317		rds_ib_set_ack(ic, state.ack_next, state.ack_required);
318	if (state.ack_recv_valid && state.ack_recv > ic->i_ack_recv) {
319		rds_send_drop_acked(conn, state.ack_recv, NULL);
320		ic->i_ack_recv = state.ack_recv;
321	}
322
323	if (rds_conn_up(conn))
324		rds_ib_attempt_ack(ic);
325}
326
327static void rds_ib_qp_event_handler(struct ib_event *event, void *data)
328{
329	struct rds_connection *conn = data;
330	struct rds_ib_connection *ic = conn->c_transport_data;
331
332	rdsdebug("conn %p ic %p event %u (%s)\n", conn, ic, event->event,
333		 ib_event_msg(event->event));
334
335	switch (event->event) {
336	case IB_EVENT_COMM_EST:
337		rdma_notify(ic->i_cm_id, IB_EVENT_COMM_EST);
338		break;
339	default:
340		rdsdebug("Fatal QP Event %u (%s) "
341			"- connection %pI4->%pI4, reconnecting\n",
342			event->event, ib_event_msg(event->event),
343			&conn->c_laddr, &conn->c_faddr);
344		rds_conn_drop(conn);
345		break;
346	}
347}
348
349static void rds_ib_cq_comp_handler_send(struct ib_cq *cq, void *context)
350{
351	struct rds_connection *conn = context;
352	struct rds_ib_connection *ic = conn->c_transport_data;
353
354	rdsdebug("conn %p cq %p\n", conn, cq);
355
356	rds_ib_stats_inc(s_ib_evt_handler_call);
357
358	tasklet_schedule(&ic->i_send_tasklet);
359}
360
361/*
362 * This needs to be very careful to not leave IS_ERR pointers around for
363 * cleanup to trip over.
364 */
365static int rds_ib_setup_qp(struct rds_connection *conn)
366{
367	struct rds_ib_connection *ic = conn->c_transport_data;
368	struct ib_device *dev = ic->i_cm_id->device;
369	struct ib_qp_init_attr attr;
370	struct ib_cq_init_attr cq_attr = {};
371	struct rds_ib_device *rds_ibdev;
372	int ret, fr_queue_space;
373
374	/*
375	 * It's normal to see a null device if an incoming connection races
376	 * with device removal, so we don't print a warning.
377	 */
378	rds_ibdev = rds_ib_get_client_data(dev);
379	if (!rds_ibdev)
380		return -EOPNOTSUPP;
381
382	/* The fr_queue_space is currently set to 512, to add extra space on
383	 * completion queue and send queue. This extra space is used for FRMR
384	 * registration and invalidation work requests
385	 */
386	fr_queue_space = (rds_ibdev->use_fastreg ? RDS_IB_DEFAULT_FR_WR : 0);
387
388	/* add the conn now so that connection establishment has the dev */
389	rds_ib_add_conn(rds_ibdev, conn);
390
391	if (rds_ibdev->max_wrs < ic->i_send_ring.w_nr + 1)
392		rds_ib_ring_resize(&ic->i_send_ring, rds_ibdev->max_wrs - 1);
393	if (rds_ibdev->max_wrs < ic->i_recv_ring.w_nr + 1)
394		rds_ib_ring_resize(&ic->i_recv_ring, rds_ibdev->max_wrs - 1);
395
396	/* Protection domain and memory range */
397	ic->i_pd = rds_ibdev->pd;
 
398
399	cq_attr.cqe = ic->i_send_ring.w_nr + fr_queue_space + 1;
400
401	ic->i_send_cq = ib_create_cq(dev, rds_ib_cq_comp_handler_send,
402				     rds_ib_cq_event_handler, conn,
403				     &cq_attr);
404	if (IS_ERR(ic->i_send_cq)) {
405		ret = PTR_ERR(ic->i_send_cq);
406		ic->i_send_cq = NULL;
407		rdsdebug("ib_create_cq send failed: %d\n", ret);
408		goto out;
409	}
410
411	cq_attr.cqe = ic->i_recv_ring.w_nr;
412	ic->i_recv_cq = ib_create_cq(dev, rds_ib_cq_comp_handler_recv,
413				     rds_ib_cq_event_handler, conn,
414				     &cq_attr);
415	if (IS_ERR(ic->i_recv_cq)) {
416		ret = PTR_ERR(ic->i_recv_cq);
417		ic->i_recv_cq = NULL;
418		rdsdebug("ib_create_cq recv failed: %d\n", ret);
419		goto out;
420	}
421
422	ret = ib_req_notify_cq(ic->i_send_cq, IB_CQ_NEXT_COMP);
423	if (ret) {
424		rdsdebug("ib_req_notify_cq send failed: %d\n", ret);
425		goto out;
426	}
427
428	ret = ib_req_notify_cq(ic->i_recv_cq, IB_CQ_SOLICITED);
429	if (ret) {
430		rdsdebug("ib_req_notify_cq recv failed: %d\n", ret);
431		goto out;
432	}
433
434	/* XXX negotiate max send/recv with remote? */
435	memset(&attr, 0, sizeof(attr));
436	attr.event_handler = rds_ib_qp_event_handler;
437	attr.qp_context = conn;
438	/* + 1 to allow for the single ack message */
439	attr.cap.max_send_wr = ic->i_send_ring.w_nr + fr_queue_space + 1;
440	attr.cap.max_recv_wr = ic->i_recv_ring.w_nr + 1;
441	attr.cap.max_send_sge = rds_ibdev->max_sge;
442	attr.cap.max_recv_sge = RDS_IB_RECV_SGE;
443	attr.sq_sig_type = IB_SIGNAL_REQ_WR;
444	attr.qp_type = IB_QPT_RC;
445	attr.send_cq = ic->i_send_cq;
446	attr.recv_cq = ic->i_recv_cq;
447	atomic_set(&ic->i_fastreg_wrs, RDS_IB_DEFAULT_FR_WR);
448
449	/*
450	 * XXX this can fail if max_*_wr is too large?  Are we supposed
451	 * to back off until we get a value that the hardware can support?
452	 */
453	ret = rdma_create_qp(ic->i_cm_id, ic->i_pd, &attr);
454	if (ret) {
455		rdsdebug("rdma_create_qp failed: %d\n", ret);
456		goto out;
457	}
458
459	ic->i_send_hdrs = ib_dma_alloc_coherent(dev,
460					   ic->i_send_ring.w_nr *
461						sizeof(struct rds_header),
462					   &ic->i_send_hdrs_dma, GFP_KERNEL);
463	if (!ic->i_send_hdrs) {
464		ret = -ENOMEM;
465		rdsdebug("ib_dma_alloc_coherent send failed\n");
466		goto out;
467	}
468
469	ic->i_recv_hdrs = ib_dma_alloc_coherent(dev,
470					   ic->i_recv_ring.w_nr *
471						sizeof(struct rds_header),
472					   &ic->i_recv_hdrs_dma, GFP_KERNEL);
473	if (!ic->i_recv_hdrs) {
474		ret = -ENOMEM;
475		rdsdebug("ib_dma_alloc_coherent recv failed\n");
476		goto out;
477	}
478
479	ic->i_ack = ib_dma_alloc_coherent(dev, sizeof(struct rds_header),
480				       &ic->i_ack_dma, GFP_KERNEL);
481	if (!ic->i_ack) {
482		ret = -ENOMEM;
483		rdsdebug("ib_dma_alloc_coherent ack failed\n");
484		goto out;
485	}
486
487	ic->i_sends = vzalloc_node(ic->i_send_ring.w_nr * sizeof(struct rds_ib_send_work),
488				   ibdev_to_node(dev));
489	if (!ic->i_sends) {
490		ret = -ENOMEM;
491		rdsdebug("send allocation failed\n");
492		goto out;
493	}
494
495	ic->i_recvs = vzalloc_node(ic->i_recv_ring.w_nr * sizeof(struct rds_ib_recv_work),
496				   ibdev_to_node(dev));
497	if (!ic->i_recvs) {
498		ret = -ENOMEM;
499		rdsdebug("recv allocation failed\n");
500		goto out;
501	}
502
503	rds_ib_recv_init_ack(ic);
504
505	rdsdebug("conn %p pd %p cq %p %p\n", conn, ic->i_pd,
506		 ic->i_send_cq, ic->i_recv_cq);
507
508out:
509	rds_ib_dev_put(rds_ibdev);
510	return ret;
511}
512
513static u32 rds_ib_protocol_compatible(struct rdma_cm_event *event)
514{
515	const struct rds_ib_connect_private *dp = event->param.conn.private_data;
516	u16 common;
517	u32 version = 0;
518
519	/*
520	 * rdma_cm private data is odd - when there is any private data in the
521	 * request, we will be given a pretty large buffer without telling us the
522	 * original size. The only way to tell the difference is by looking at
523	 * the contents, which are initialized to zero.
524	 * If the protocol version fields aren't set, this is a connection attempt
525	 * from an older version. This could could be 3.0 or 2.0 - we can't tell.
526	 * We really should have changed this for OFED 1.3 :-(
527	 */
528
529	/* Be paranoid. RDS always has privdata */
530	if (!event->param.conn.private_data_len) {
531		printk(KERN_NOTICE "RDS incoming connection has no private data, "
532			"rejecting\n");
533		return 0;
534	}
535
536	/* Even if len is crap *now* I still want to check it. -ASG */
537	if (event->param.conn.private_data_len < sizeof (*dp) ||
538	    dp->dp_protocol_major == 0)
539		return RDS_PROTOCOL_3_0;
540
541	common = be16_to_cpu(dp->dp_protocol_minor_mask) & RDS_IB_SUPPORTED_PROTOCOLS;
542	if (dp->dp_protocol_major == 3 && common) {
543		version = RDS_PROTOCOL_3_0;
544		while ((common >>= 1) != 0)
545			version++;
546	} else
547		printk_ratelimited(KERN_NOTICE "RDS: Connection from %pI4 using incompatible protocol version %u.%u\n",
548				&dp->dp_saddr,
549				dp->dp_protocol_major,
550				dp->dp_protocol_minor);
 
551	return version;
552}
553
554int rds_ib_cm_handle_connect(struct rdma_cm_id *cm_id,
555				    struct rdma_cm_event *event)
556{
557	__be64 lguid = cm_id->route.path_rec->sgid.global.interface_id;
558	__be64 fguid = cm_id->route.path_rec->dgid.global.interface_id;
559	const struct rds_ib_connect_private *dp = event->param.conn.private_data;
560	struct rds_ib_connect_private dp_rep;
561	struct rds_connection *conn = NULL;
562	struct rds_ib_connection *ic = NULL;
563	struct rdma_conn_param conn_param;
564	u32 version;
565	int err = 1, destroy = 1;
566
567	/* Check whether the remote protocol version matches ours. */
568	version = rds_ib_protocol_compatible(event);
569	if (!version)
570		goto out;
571
572	rdsdebug("saddr %pI4 daddr %pI4 RDSv%u.%u lguid 0x%llx fguid "
573		 "0x%llx\n", &dp->dp_saddr, &dp->dp_daddr,
574		 RDS_PROTOCOL_MAJOR(version), RDS_PROTOCOL_MINOR(version),
575		 (unsigned long long)be64_to_cpu(lguid),
576		 (unsigned long long)be64_to_cpu(fguid));
577
578	/* RDS/IB is not currently netns aware, thus init_net */
579	conn = rds_conn_create(&init_net, dp->dp_daddr, dp->dp_saddr,
580			       &rds_ib_transport, GFP_KERNEL);
581	if (IS_ERR(conn)) {
582		rdsdebug("rds_conn_create failed (%ld)\n", PTR_ERR(conn));
583		conn = NULL;
584		goto out;
585	}
586
587	/*
588	 * The connection request may occur while the
589	 * previous connection exist, e.g. in case of failover.
590	 * But as connections may be initiated simultaneously
591	 * by both hosts, we have a random backoff mechanism -
592	 * see the comment above rds_queue_reconnect()
593	 */
594	mutex_lock(&conn->c_cm_lock);
595	if (!rds_conn_transition(conn, RDS_CONN_DOWN, RDS_CONN_CONNECTING)) {
596		if (rds_conn_state(conn) == RDS_CONN_UP) {
597			rdsdebug("incoming connect while connecting\n");
598			rds_conn_drop(conn);
599			rds_ib_stats_inc(s_ib_listen_closed_stale);
600		} else
601		if (rds_conn_state(conn) == RDS_CONN_CONNECTING) {
602			/* Wait and see - our connect may still be succeeding */
603			rds_ib_stats_inc(s_ib_connect_raced);
604		}
605		goto out;
606	}
607
608	ic = conn->c_transport_data;
609
610	rds_ib_set_protocol(conn, version);
611	rds_ib_set_flow_control(conn, be32_to_cpu(dp->dp_credit));
612
613	/* If the peer gave us the last packet it saw, process this as if
614	 * we had received a regular ACK. */
615	if (dp->dp_ack_seq)
616		rds_send_drop_acked(conn, be64_to_cpu(dp->dp_ack_seq), NULL);
617
618	BUG_ON(cm_id->context);
619	BUG_ON(ic->i_cm_id);
620
621	ic->i_cm_id = cm_id;
622	cm_id->context = conn;
623
624	/* We got halfway through setting up the ib_connection, if we
625	 * fail now, we have to take the long route out of this mess. */
626	destroy = 0;
627
628	err = rds_ib_setup_qp(conn);
629	if (err) {
630		rds_ib_conn_error(conn, "rds_ib_setup_qp failed (%d)\n", err);
631		goto out;
632	}
633
634	rds_ib_cm_fill_conn_param(conn, &conn_param, &dp_rep, version,
635		event->param.conn.responder_resources,
636		event->param.conn.initiator_depth);
637
638	/* rdma_accept() calls rdma_reject() internally if it fails */
639	err = rdma_accept(cm_id, &conn_param);
640	if (err)
641		rds_ib_conn_error(conn, "rdma_accept failed (%d)\n", err);
642
643out:
644	if (conn)
645		mutex_unlock(&conn->c_cm_lock);
646	if (err)
647		rdma_reject(cm_id, NULL, 0);
648	return destroy;
649}
650
651
652int rds_ib_cm_initiate_connect(struct rdma_cm_id *cm_id)
653{
654	struct rds_connection *conn = cm_id->context;
655	struct rds_ib_connection *ic = conn->c_transport_data;
656	struct rdma_conn_param conn_param;
657	struct rds_ib_connect_private dp;
658	int ret;
659
660	/* If the peer doesn't do protocol negotiation, we must
661	 * default to RDSv3.0 */
662	rds_ib_set_protocol(conn, RDS_PROTOCOL_3_0);
663	ic->i_flowctl = rds_ib_sysctl_flow_control;	/* advertise flow control */
664
665	ret = rds_ib_setup_qp(conn);
666	if (ret) {
667		rds_ib_conn_error(conn, "rds_ib_setup_qp failed (%d)\n", ret);
668		goto out;
669	}
670
671	rds_ib_cm_fill_conn_param(conn, &conn_param, &dp, RDS_PROTOCOL_VERSION,
672		UINT_MAX, UINT_MAX);
673	ret = rdma_connect(cm_id, &conn_param);
674	if (ret)
675		rds_ib_conn_error(conn, "rdma_connect failed (%d)\n", ret);
676
677out:
678	/* Beware - returning non-zero tells the rdma_cm to destroy
679	 * the cm_id. We should certainly not do it as long as we still
680	 * "own" the cm_id. */
681	if (ret) {
682		if (ic->i_cm_id == cm_id)
683			ret = 0;
684	}
685	return ret;
686}
687
688int rds_ib_conn_path_connect(struct rds_conn_path *cp)
689{
690	struct rds_connection *conn = cp->cp_conn;
691	struct rds_ib_connection *ic = conn->c_transport_data;
692	struct sockaddr_in src, dest;
693	int ret;
694
695	/* XXX I wonder what affect the port space has */
696	/* delegate cm event handler to rdma_transport */
697	ic->i_cm_id = rdma_create_id(&init_net, rds_rdma_cm_event_handler, conn,
698				     RDMA_PS_TCP, IB_QPT_RC);
699	if (IS_ERR(ic->i_cm_id)) {
700		ret = PTR_ERR(ic->i_cm_id);
701		ic->i_cm_id = NULL;
702		rdsdebug("rdma_create_id() failed: %d\n", ret);
703		goto out;
704	}
705
706	rdsdebug("created cm id %p for conn %p\n", ic->i_cm_id, conn);
707
708	src.sin_family = AF_INET;
709	src.sin_addr.s_addr = (__force u32)conn->c_laddr;
710	src.sin_port = (__force u16)htons(0);
711
712	dest.sin_family = AF_INET;
713	dest.sin_addr.s_addr = (__force u32)conn->c_faddr;
714	dest.sin_port = (__force u16)htons(RDS_PORT);
715
716	ret = rdma_resolve_addr(ic->i_cm_id, (struct sockaddr *)&src,
717				(struct sockaddr *)&dest,
718				RDS_RDMA_RESOLVE_TIMEOUT_MS);
719	if (ret) {
720		rdsdebug("addr resolve failed for cm id %p: %d\n", ic->i_cm_id,
721			 ret);
722		rdma_destroy_id(ic->i_cm_id);
723		ic->i_cm_id = NULL;
724	}
725
726out:
727	return ret;
728}
729
730/*
731 * This is so careful about only cleaning up resources that were built up
732 * so that it can be called at any point during startup.  In fact it
733 * can be called multiple times for a given connection.
734 */
735void rds_ib_conn_path_shutdown(struct rds_conn_path *cp)
736{
737	struct rds_connection *conn = cp->cp_conn;
738	struct rds_ib_connection *ic = conn->c_transport_data;
739	int err = 0;
740
741	rdsdebug("cm %p pd %p cq %p %p qp %p\n", ic->i_cm_id,
742		 ic->i_pd, ic->i_send_cq, ic->i_recv_cq,
743		 ic->i_cm_id ? ic->i_cm_id->qp : NULL);
744
745	if (ic->i_cm_id) {
746		struct ib_device *dev = ic->i_cm_id->device;
747
748		rdsdebug("disconnecting cm %p\n", ic->i_cm_id);
749		err = rdma_disconnect(ic->i_cm_id);
750		if (err) {
751			/* Actually this may happen quite frequently, when
752			 * an outgoing connect raced with an incoming connect.
753			 */
754			rdsdebug("failed to disconnect, cm: %p err %d\n",
755				ic->i_cm_id, err);
756		}
757
758		/*
759		 * We want to wait for tx and rx completion to finish
760		 * before we tear down the connection, but we have to be
761		 * careful not to get stuck waiting on a send ring that
762		 * only has unsignaled sends in it.  We've shutdown new
763		 * sends before getting here so by waiting for signaled
764		 * sends to complete we're ensured that there will be no
765		 * more tx processing.
766		 */
767		wait_event(rds_ib_ring_empty_wait,
768			   rds_ib_ring_empty(&ic->i_recv_ring) &&
769			   (atomic_read(&ic->i_signaled_sends) == 0) &&
770			   (atomic_read(&ic->i_fastreg_wrs) == RDS_IB_DEFAULT_FR_WR));
771		tasklet_kill(&ic->i_send_tasklet);
772		tasklet_kill(&ic->i_recv_tasklet);
773
774		/* first destroy the ib state that generates callbacks */
775		if (ic->i_cm_id->qp)
776			rdma_destroy_qp(ic->i_cm_id);
777		if (ic->i_send_cq)
778			ib_destroy_cq(ic->i_send_cq);
779		if (ic->i_recv_cq)
780			ib_destroy_cq(ic->i_recv_cq);
781
782		/* then free the resources that ib callbacks use */
783		if (ic->i_send_hdrs)
784			ib_dma_free_coherent(dev,
785					   ic->i_send_ring.w_nr *
786						sizeof(struct rds_header),
787					   ic->i_send_hdrs,
788					   ic->i_send_hdrs_dma);
789
790		if (ic->i_recv_hdrs)
791			ib_dma_free_coherent(dev,
792					   ic->i_recv_ring.w_nr *
793						sizeof(struct rds_header),
794					   ic->i_recv_hdrs,
795					   ic->i_recv_hdrs_dma);
796
797		if (ic->i_ack)
798			ib_dma_free_coherent(dev, sizeof(struct rds_header),
799					     ic->i_ack, ic->i_ack_dma);
800
801		if (ic->i_sends)
802			rds_ib_send_clear_ring(ic);
803		if (ic->i_recvs)
804			rds_ib_recv_clear_ring(ic);
805
 
 
 
 
 
 
806		rdma_destroy_id(ic->i_cm_id);
807
808		/*
809		 * Move connection back to the nodev list.
810		 */
811		if (ic->rds_ibdev)
812			rds_ib_remove_conn(ic->rds_ibdev, conn);
813
814		ic->i_cm_id = NULL;
815		ic->i_pd = NULL;
 
816		ic->i_send_cq = NULL;
817		ic->i_recv_cq = NULL;
818		ic->i_send_hdrs = NULL;
819		ic->i_recv_hdrs = NULL;
820		ic->i_ack = NULL;
821	}
822	BUG_ON(ic->rds_ibdev);
823
824	/* Clear pending transmit */
825	if (ic->i_data_op) {
826		struct rds_message *rm;
827
828		rm = container_of(ic->i_data_op, struct rds_message, data);
829		rds_message_put(rm);
830		ic->i_data_op = NULL;
831	}
832
833	/* Clear the ACK state */
834	clear_bit(IB_ACK_IN_FLIGHT, &ic->i_ack_flags);
835#ifdef KERNEL_HAS_ATOMIC64
836	atomic64_set(&ic->i_ack_next, 0);
837#else
838	ic->i_ack_next = 0;
839#endif
840	ic->i_ack_recv = 0;
841
842	/* Clear flow control state */
843	ic->i_flowctl = 0;
844	atomic_set(&ic->i_credits, 0);
845
846	rds_ib_ring_init(&ic->i_send_ring, rds_ib_sysctl_max_send_wr);
847	rds_ib_ring_init(&ic->i_recv_ring, rds_ib_sysctl_max_recv_wr);
848
849	if (ic->i_ibinc) {
850		rds_inc_put(&ic->i_ibinc->ii_inc);
851		ic->i_ibinc = NULL;
852	}
853
854	vfree(ic->i_sends);
855	ic->i_sends = NULL;
856	vfree(ic->i_recvs);
857	ic->i_recvs = NULL;
858}
859
860int rds_ib_conn_alloc(struct rds_connection *conn, gfp_t gfp)
861{
862	struct rds_ib_connection *ic;
863	unsigned long flags;
864	int ret;
865
866	/* XXX too lazy? */
867	ic = kzalloc(sizeof(struct rds_ib_connection), gfp);
868	if (!ic)
869		return -ENOMEM;
870
871	ret = rds_ib_recv_alloc_caches(ic);
872	if (ret) {
873		kfree(ic);
874		return ret;
875	}
876
877	INIT_LIST_HEAD(&ic->ib_node);
878	tasklet_init(&ic->i_send_tasklet, rds_ib_tasklet_fn_send,
879		     (unsigned long)ic);
880	tasklet_init(&ic->i_recv_tasklet, rds_ib_tasklet_fn_recv,
881		     (unsigned long)ic);
882	mutex_init(&ic->i_recv_mutex);
883#ifndef KERNEL_HAS_ATOMIC64
884	spin_lock_init(&ic->i_ack_lock);
885#endif
886	atomic_set(&ic->i_signaled_sends, 0);
887
888	/*
889	 * rds_ib_conn_shutdown() waits for these to be emptied so they
890	 * must be initialized before it can be called.
891	 */
892	rds_ib_ring_init(&ic->i_send_ring, rds_ib_sysctl_max_send_wr);
893	rds_ib_ring_init(&ic->i_recv_ring, rds_ib_sysctl_max_recv_wr);
894
895	ic->conn = conn;
896	conn->c_transport_data = ic;
897
898	spin_lock_irqsave(&ib_nodev_conns_lock, flags);
899	list_add_tail(&ic->ib_node, &ib_nodev_conns);
900	spin_unlock_irqrestore(&ib_nodev_conns_lock, flags);
901
902
903	rdsdebug("conn %p conn ic %p\n", conn, conn->c_transport_data);
904	return 0;
905}
906
907/*
908 * Free a connection. Connection must be shut down and not set for reconnect.
909 */
910void rds_ib_conn_free(void *arg)
911{
912	struct rds_ib_connection *ic = arg;
913	spinlock_t	*lock_ptr;
914
915	rdsdebug("ic %p\n", ic);
916
917	/*
918	 * Conn is either on a dev's list or on the nodev list.
919	 * A race with shutdown() or connect() would cause problems
920	 * (since rds_ibdev would change) but that should never happen.
921	 */
922	lock_ptr = ic->rds_ibdev ? &ic->rds_ibdev->spinlock : &ib_nodev_conns_lock;
923
924	spin_lock_irq(lock_ptr);
925	list_del(&ic->ib_node);
926	spin_unlock_irq(lock_ptr);
927
928	rds_ib_recv_free_caches(ic);
929
930	kfree(ic);
931}
932
933
934/*
935 * An error occurred on the connection
936 */
937void
938__rds_ib_conn_error(struct rds_connection *conn, const char *fmt, ...)
939{
940	va_list ap;
941
942	rds_conn_drop(conn);
943
944	va_start(ap, fmt);
945	vprintk(fmt, ap);
946	va_end(ap);
947}