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v4.6
  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
 42/*
 43 * Set the selected protocol version
 44 */
 45static void rds_ib_set_protocol(struct rds_connection *conn, unsigned int version)
 46{
 47	conn->c_version = version;
 48}
 49
 50/*
 51 * Set up flow control
 52 */
 53static void rds_ib_set_flow_control(struct rds_connection *conn, u32 credits)
 54{
 55	struct rds_ib_connection *ic = conn->c_transport_data;
 56
 57	if (rds_ib_sysctl_flow_control && credits != 0) {
 58		/* We're doing flow control */
 59		ic->i_flowctl = 1;
 60		rds_ib_send_add_credits(conn, credits);
 61	} else {
 62		ic->i_flowctl = 0;
 63	}
 64}
 65
 66/*
 67 * Tune RNR behavior. Without flow control, we use a rather
 68 * low timeout, but not the absolute minimum - this should
 69 * be tunable.
 70 *
 71 * We already set the RNR retry count to 7 (which is the
 72 * smallest infinite number :-) above.
 73 * If flow control is off, we want to change this back to 0
 74 * so that we learn quickly when our credit accounting is
 75 * buggy.
 76 *
 77 * Caller passes in a qp_attr pointer - don't waste stack spacv
 78 * by allocation this twice.
 79 */
 80static void
 81rds_ib_tune_rnr(struct rds_ib_connection *ic, struct ib_qp_attr *attr)
 82{
 83	int ret;
 84
 85	attr->min_rnr_timer = IB_RNR_TIMER_000_32;
 86	ret = ib_modify_qp(ic->i_cm_id->qp, attr, IB_QP_MIN_RNR_TIMER);
 87	if (ret)
 88		printk(KERN_NOTICE "ib_modify_qp(IB_QP_MIN_RNR_TIMER): err=%d\n", -ret);
 89}
 90
 91/*
 92 * Connection established.
 93 * We get here for both outgoing and incoming connection.
 94 */
 95void rds_ib_cm_connect_complete(struct rds_connection *conn, struct rdma_cm_event *event)
 96{
 97	const struct rds_ib_connect_private *dp = NULL;
 98	struct rds_ib_connection *ic = conn->c_transport_data;
 99	struct ib_qp_attr qp_attr;
100	int err;
101
102	if (event->param.conn.private_data_len >= sizeof(*dp)) {
103		dp = event->param.conn.private_data;
104
105		/* make sure it isn't empty data */
106		if (dp->dp_protocol_major) {
107			rds_ib_set_protocol(conn,
108				RDS_PROTOCOL(dp->dp_protocol_major,
109				dp->dp_protocol_minor));
110			rds_ib_set_flow_control(conn, be32_to_cpu(dp->dp_credit));
111		}
112	}
113
114	if (conn->c_version < RDS_PROTOCOL(3,1)) {
115		printk(KERN_NOTICE "RDS/IB: Connection to %pI4 version %u.%u failed,"
116		       " no longer supported\n",
117		       &conn->c_faddr,
118		       RDS_PROTOCOL_MAJOR(conn->c_version),
119		       RDS_PROTOCOL_MINOR(conn->c_version));
120		rds_conn_destroy(conn);
121		return;
122	} else {
123		printk(KERN_NOTICE "RDS/IB: connected to %pI4 version %u.%u%s\n",
124		       &conn->c_faddr,
125		       RDS_PROTOCOL_MAJOR(conn->c_version),
126		       RDS_PROTOCOL_MINOR(conn->c_version),
127		       ic->i_flowctl ? ", flow control" : "");
 
128	}
129
130	/*
131	 * Init rings and fill recv. this needs to wait until protocol negotiation
132	 * is complete, since ring layout is different from 3.0 to 3.1.
 
 
133	 */
134	rds_ib_send_init_ring(ic);
135	rds_ib_recv_init_ring(ic);
136	/* Post receive buffers - as a side effect, this will update
137	 * the posted credit count. */
138	rds_ib_recv_refill(conn, 1, GFP_KERNEL);
139
140	/* Tune RNR behavior */
141	rds_ib_tune_rnr(ic, &qp_attr);
142
143	qp_attr.qp_state = IB_QPS_RTS;
144	err = ib_modify_qp(ic->i_cm_id->qp, &qp_attr, IB_QP_STATE);
145	if (err)
146		printk(KERN_NOTICE "ib_modify_qp(IB_QP_STATE, RTS): err=%d\n", err);
147
148	/* update ib_device with this local ipaddr */
149	err = rds_ib_update_ipaddr(ic->rds_ibdev, conn->c_laddr);
150	if (err)
151		printk(KERN_ERR "rds_ib_update_ipaddr failed (%d)\n",
152			err);
153
154	/* If the peer gave us the last packet it saw, process this as if
155	 * we had received a regular ACK. */
156	if (dp) {
157		/* dp structure start is not guaranteed to be 8 bytes aligned.
158		 * Since dp_ack_seq is 64-bit extended load operations can be
159		 * used so go through get_unaligned to avoid unaligned errors.
160		 */
161		__be64 dp_ack_seq = get_unaligned(&dp->dp_ack_seq);
162
163		if (dp_ack_seq)
164			rds_send_drop_acked(conn, be64_to_cpu(dp_ack_seq),
165					    NULL);
166	}
167
168	rds_connect_complete(conn);
169}
170
171static void rds_ib_cm_fill_conn_param(struct rds_connection *conn,
172			struct rdma_conn_param *conn_param,
173			struct rds_ib_connect_private *dp,
174			u32 protocol_version,
175			u32 max_responder_resources,
176			u32 max_initiator_depth)
177{
178	struct rds_ib_connection *ic = conn->c_transport_data;
179	struct rds_ib_device *rds_ibdev = ic->rds_ibdev;
180
181	memset(conn_param, 0, sizeof(struct rdma_conn_param));
182
183	conn_param->responder_resources =
184		min_t(u32, rds_ibdev->max_responder_resources, max_responder_resources);
185	conn_param->initiator_depth =
186		min_t(u32, rds_ibdev->max_initiator_depth, max_initiator_depth);
187	conn_param->retry_count = min_t(unsigned int, rds_ib_retry_count, 7);
188	conn_param->rnr_retry_count = 7;
189
190	if (dp) {
191		memset(dp, 0, sizeof(*dp));
192		dp->dp_saddr = conn->c_laddr;
193		dp->dp_daddr = conn->c_faddr;
194		dp->dp_protocol_major = RDS_PROTOCOL_MAJOR(protocol_version);
195		dp->dp_protocol_minor = RDS_PROTOCOL_MINOR(protocol_version);
196		dp->dp_protocol_minor_mask = cpu_to_be16(RDS_IB_SUPPORTED_PROTOCOLS);
197		dp->dp_ack_seq = cpu_to_be64(rds_ib_piggyb_ack(ic));
198
199		/* Advertise flow control */
200		if (ic->i_flowctl) {
201			unsigned int credits;
202
203			credits = IB_GET_POST_CREDITS(atomic_read(&ic->i_credits));
204			dp->dp_credit = cpu_to_be32(credits);
205			atomic_sub(IB_SET_POST_CREDITS(credits), &ic->i_credits);
206		}
207
208		conn_param->private_data = dp;
209		conn_param->private_data_len = sizeof(*dp);
210	}
211}
212
213static void rds_ib_cq_event_handler(struct ib_event *event, void *data)
214{
215	rdsdebug("event %u (%s) data %p\n",
216		 event->event, ib_event_msg(event->event), data);
217}
218
219/* Plucking the oldest entry from the ring can be done concurrently with
220 * the thread refilling the ring.  Each ring operation is protected by
221 * spinlocks and the transient state of refilling doesn't change the
222 * recording of which entry is oldest.
223 *
224 * This relies on IB only calling one cq comp_handler for each cq so that
225 * there will only be one caller of rds_recv_incoming() per RDS connection.
226 */
227static void rds_ib_cq_comp_handler_recv(struct ib_cq *cq, void *context)
228{
229	struct rds_connection *conn = context;
230	struct rds_ib_connection *ic = conn->c_transport_data;
231
232	rdsdebug("conn %p cq %p\n", conn, cq);
233
234	rds_ib_stats_inc(s_ib_evt_handler_call);
235
236	tasklet_schedule(&ic->i_recv_tasklet);
237}
238
239static void poll_scq(struct rds_ib_connection *ic, struct ib_cq *cq,
240		     struct ib_wc *wcs)
241{
242	int nr, i;
243	struct ib_wc *wc;
244
245	while ((nr = ib_poll_cq(cq, RDS_IB_WC_MAX, wcs)) > 0) {
246		for (i = 0; i < nr; i++) {
247			wc = wcs + i;
248			rdsdebug("wc wr_id 0x%llx status %u byte_len %u imm_data %u\n",
249				 (unsigned long long)wc->wr_id, wc->status,
250				 wc->byte_len, be32_to_cpu(wc->ex.imm_data));
251
252			if (wc->wr_id <= ic->i_send_ring.w_nr ||
253			    wc->wr_id == RDS_IB_ACK_WR_ID)
254				rds_ib_send_cqe_handler(ic, wc);
255			else
256				rds_ib_mr_cqe_handler(ic, wc);
257
258		}
259	}
260}
261
262static void rds_ib_tasklet_fn_send(unsigned long data)
263{
264	struct rds_ib_connection *ic = (struct rds_ib_connection *)data;
265	struct rds_connection *conn = ic->conn;
266
267	rds_ib_stats_inc(s_ib_tasklet_call);
268
 
 
 
 
269	poll_scq(ic, ic->i_send_cq, ic->i_send_wc);
270	ib_req_notify_cq(ic->i_send_cq, IB_CQ_NEXT_COMP);
271	poll_scq(ic, ic->i_send_cq, ic->i_send_wc);
272
273	if (rds_conn_up(conn) &&
274	    (!test_bit(RDS_LL_SEND_FULL, &conn->c_flags) ||
275	    test_bit(0, &conn->c_map_queued)))
276		rds_send_xmit(ic->conn);
277}
278
279static void poll_rcq(struct rds_ib_connection *ic, struct ib_cq *cq,
280		     struct ib_wc *wcs,
281		     struct rds_ib_ack_state *ack_state)
282{
283	int nr, i;
284	struct ib_wc *wc;
285
286	while ((nr = ib_poll_cq(cq, RDS_IB_WC_MAX, wcs)) > 0) {
287		for (i = 0; i < nr; i++) {
288			wc = wcs + i;
289			rdsdebug("wc wr_id 0x%llx status %u byte_len %u imm_data %u\n",
290				 (unsigned long long)wc->wr_id, wc->status,
291				 wc->byte_len, be32_to_cpu(wc->ex.imm_data));
292
293			rds_ib_recv_cqe_handler(ic, wc, ack_state);
294		}
295	}
296}
297
298static void rds_ib_tasklet_fn_recv(unsigned long data)
299{
300	struct rds_ib_connection *ic = (struct rds_ib_connection *)data;
301	struct rds_connection *conn = ic->conn;
302	struct rds_ib_device *rds_ibdev = ic->rds_ibdev;
303	struct rds_ib_ack_state state;
304
305	if (!rds_ibdev)
306		rds_conn_drop(conn);
307
308	rds_ib_stats_inc(s_ib_tasklet_call);
309
 
 
 
 
310	memset(&state, 0, sizeof(state));
311	poll_rcq(ic, ic->i_recv_cq, ic->i_recv_wc, &state);
312	ib_req_notify_cq(ic->i_recv_cq, IB_CQ_SOLICITED);
313	poll_rcq(ic, ic->i_recv_cq, ic->i_recv_wc, &state);
314
315	if (state.ack_next_valid)
316		rds_ib_set_ack(ic, state.ack_next, state.ack_required);
317	if (state.ack_recv_valid && state.ack_recv > ic->i_ack_recv) {
318		rds_send_drop_acked(conn, state.ack_recv, NULL);
319		ic->i_ack_recv = state.ack_recv;
320	}
321
322	if (rds_conn_up(conn))
323		rds_ib_attempt_ack(ic);
324}
325
326static void rds_ib_qp_event_handler(struct ib_event *event, void *data)
327{
328	struct rds_connection *conn = data;
329	struct rds_ib_connection *ic = conn->c_transport_data;
330
331	rdsdebug("conn %p ic %p event %u (%s)\n", conn, ic, event->event,
332		 ib_event_msg(event->event));
333
334	switch (event->event) {
335	case IB_EVENT_COMM_EST:
336		rdma_notify(ic->i_cm_id, IB_EVENT_COMM_EST);
337		break;
338	default:
339		rdsdebug("Fatal QP Event %u (%s) "
340			"- connection %pI4->%pI4, reconnecting\n",
341			event->event, ib_event_msg(event->event),
342			&conn->c_laddr, &conn->c_faddr);
343		rds_conn_drop(conn);
344		break;
345	}
346}
347
348static void rds_ib_cq_comp_handler_send(struct ib_cq *cq, void *context)
349{
350	struct rds_connection *conn = context;
351	struct rds_ib_connection *ic = conn->c_transport_data;
352
353	rdsdebug("conn %p cq %p\n", conn, cq);
354
355	rds_ib_stats_inc(s_ib_evt_handler_call);
356
357	tasklet_schedule(&ic->i_send_tasklet);
358}
359
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
360/*
361 * This needs to be very careful to not leave IS_ERR pointers around for
362 * cleanup to trip over.
363 */
364static int rds_ib_setup_qp(struct rds_connection *conn)
365{
366	struct rds_ib_connection *ic = conn->c_transport_data;
367	struct ib_device *dev = ic->i_cm_id->device;
368	struct ib_qp_init_attr attr;
369	struct ib_cq_init_attr cq_attr = {};
370	struct rds_ib_device *rds_ibdev;
371	int ret, fr_queue_space;
372
373	/*
374	 * It's normal to see a null device if an incoming connection races
375	 * with device removal, so we don't print a warning.
376	 */
377	rds_ibdev = rds_ib_get_client_data(dev);
378	if (!rds_ibdev)
379		return -EOPNOTSUPP;
380
381	/* The fr_queue_space is currently set to 512, to add extra space on
382	 * completion queue and send queue. This extra space is used for FRMR
383	 * registration and invalidation work requests
384	 */
385	fr_queue_space = (rds_ibdev->use_fastreg ? RDS_IB_DEFAULT_FR_WR : 0);
 
 
 
386
387	/* add the conn now so that connection establishment has the dev */
388	rds_ib_add_conn(rds_ibdev, conn);
389
390	if (rds_ibdev->max_wrs < ic->i_send_ring.w_nr + 1)
391		rds_ib_ring_resize(&ic->i_send_ring, rds_ibdev->max_wrs - 1);
392	if (rds_ibdev->max_wrs < ic->i_recv_ring.w_nr + 1)
393		rds_ib_ring_resize(&ic->i_recv_ring, rds_ibdev->max_wrs - 1);
394
395	/* Protection domain and memory range */
396	ic->i_pd = rds_ibdev->pd;
397
 
398	cq_attr.cqe = ic->i_send_ring.w_nr + fr_queue_space + 1;
399
400	ic->i_send_cq = ib_create_cq(dev, rds_ib_cq_comp_handler_send,
401				     rds_ib_cq_event_handler, conn,
402				     &cq_attr);
403	if (IS_ERR(ic->i_send_cq)) {
404		ret = PTR_ERR(ic->i_send_cq);
405		ic->i_send_cq = NULL;
 
406		rdsdebug("ib_create_cq send failed: %d\n", ret);
407		goto out;
408	}
409
 
410	cq_attr.cqe = ic->i_recv_ring.w_nr;
 
411	ic->i_recv_cq = ib_create_cq(dev, rds_ib_cq_comp_handler_recv,
412				     rds_ib_cq_event_handler, conn,
413				     &cq_attr);
414	if (IS_ERR(ic->i_recv_cq)) {
415		ret = PTR_ERR(ic->i_recv_cq);
416		ic->i_recv_cq = NULL;
 
417		rdsdebug("ib_create_cq recv failed: %d\n", ret);
418		goto out;
419	}
420
421	ret = ib_req_notify_cq(ic->i_send_cq, IB_CQ_NEXT_COMP);
422	if (ret) {
423		rdsdebug("ib_req_notify_cq send failed: %d\n", ret);
424		goto out;
425	}
426
427	ret = ib_req_notify_cq(ic->i_recv_cq, IB_CQ_SOLICITED);
428	if (ret) {
429		rdsdebug("ib_req_notify_cq recv failed: %d\n", ret);
430		goto out;
431	}
432
433	/* XXX negotiate max send/recv with remote? */
434	memset(&attr, 0, sizeof(attr));
435	attr.event_handler = rds_ib_qp_event_handler;
436	attr.qp_context = conn;
437	/* + 1 to allow for the single ack message */
438	attr.cap.max_send_wr = ic->i_send_ring.w_nr + fr_queue_space + 1;
439	attr.cap.max_recv_wr = ic->i_recv_ring.w_nr + 1;
440	attr.cap.max_send_sge = rds_ibdev->max_sge;
441	attr.cap.max_recv_sge = RDS_IB_RECV_SGE;
442	attr.sq_sig_type = IB_SIGNAL_REQ_WR;
443	attr.qp_type = IB_QPT_RC;
444	attr.send_cq = ic->i_send_cq;
445	attr.recv_cq = ic->i_recv_cq;
446	atomic_set(&ic->i_fastreg_wrs, RDS_IB_DEFAULT_FR_WR);
 
447
448	/*
449	 * XXX this can fail if max_*_wr is too large?  Are we supposed
450	 * to back off until we get a value that the hardware can support?
451	 */
452	ret = rdma_create_qp(ic->i_cm_id, ic->i_pd, &attr);
453	if (ret) {
454		rdsdebug("rdma_create_qp failed: %d\n", ret);
455		goto out;
456	}
457
458	ic->i_send_hdrs = ib_dma_alloc_coherent(dev,
459					   ic->i_send_ring.w_nr *
460						sizeof(struct rds_header),
461					   &ic->i_send_hdrs_dma, GFP_KERNEL);
462	if (!ic->i_send_hdrs) {
463		ret = -ENOMEM;
464		rdsdebug("ib_dma_alloc_coherent send failed\n");
465		goto out;
466	}
467
468	ic->i_recv_hdrs = ib_dma_alloc_coherent(dev,
469					   ic->i_recv_ring.w_nr *
470						sizeof(struct rds_header),
471					   &ic->i_recv_hdrs_dma, GFP_KERNEL);
472	if (!ic->i_recv_hdrs) {
473		ret = -ENOMEM;
474		rdsdebug("ib_dma_alloc_coherent recv failed\n");
475		goto out;
476	}
477
478	ic->i_ack = ib_dma_alloc_coherent(dev, sizeof(struct rds_header),
479				       &ic->i_ack_dma, GFP_KERNEL);
480	if (!ic->i_ack) {
481		ret = -ENOMEM;
482		rdsdebug("ib_dma_alloc_coherent ack failed\n");
483		goto out;
484	}
485
486	ic->i_sends = vzalloc_node(ic->i_send_ring.w_nr * sizeof(struct rds_ib_send_work),
487				   ibdev_to_node(dev));
488	if (!ic->i_sends) {
489		ret = -ENOMEM;
490		rdsdebug("send allocation failed\n");
491		goto out;
492	}
493
494	ic->i_recvs = vzalloc_node(ic->i_recv_ring.w_nr * sizeof(struct rds_ib_recv_work),
495				   ibdev_to_node(dev));
496	if (!ic->i_recvs) {
497		ret = -ENOMEM;
498		rdsdebug("recv allocation failed\n");
499		goto out;
500	}
501
502	rds_ib_recv_init_ack(ic);
503
504	rdsdebug("conn %p pd %p cq %p %p\n", conn, ic->i_pd,
505		 ic->i_send_cq, ic->i_recv_cq);
506
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
507out:
508	rds_ib_dev_put(rds_ibdev);
 
509	return ret;
510}
511
512static u32 rds_ib_protocol_compatible(struct rdma_cm_event *event)
513{
514	const struct rds_ib_connect_private *dp = event->param.conn.private_data;
515	u16 common;
516	u32 version = 0;
517
518	/*
519	 * rdma_cm private data is odd - when there is any private data in the
520	 * request, we will be given a pretty large buffer without telling us the
521	 * original size. The only way to tell the difference is by looking at
522	 * the contents, which are initialized to zero.
523	 * If the protocol version fields aren't set, this is a connection attempt
524	 * from an older version. This could could be 3.0 or 2.0 - we can't tell.
525	 * We really should have changed this for OFED 1.3 :-(
526	 */
527
528	/* Be paranoid. RDS always has privdata */
529	if (!event->param.conn.private_data_len) {
530		printk(KERN_NOTICE "RDS incoming connection has no private data, "
531			"rejecting\n");
532		return 0;
533	}
534
535	/* Even if len is crap *now* I still want to check it. -ASG */
536	if (event->param.conn.private_data_len < sizeof (*dp) ||
537	    dp->dp_protocol_major == 0)
538		return RDS_PROTOCOL_3_0;
539
540	common = be16_to_cpu(dp->dp_protocol_minor_mask) & RDS_IB_SUPPORTED_PROTOCOLS;
541	if (dp->dp_protocol_major == 3 && common) {
542		version = RDS_PROTOCOL_3_0;
543		while ((common >>= 1) != 0)
544			version++;
545	} else
546		printk_ratelimited(KERN_NOTICE "RDS: Connection from %pI4 using incompatible protocol version %u.%u\n",
547				&dp->dp_saddr,
548				dp->dp_protocol_major,
549				dp->dp_protocol_minor);
550	return version;
551}
552
553int rds_ib_cm_handle_connect(struct rdma_cm_id *cm_id,
554				    struct rdma_cm_event *event)
555{
556	__be64 lguid = cm_id->route.path_rec->sgid.global.interface_id;
557	__be64 fguid = cm_id->route.path_rec->dgid.global.interface_id;
558	const struct rds_ib_connect_private *dp = event->param.conn.private_data;
559	struct rds_ib_connect_private dp_rep;
560	struct rds_connection *conn = NULL;
561	struct rds_ib_connection *ic = NULL;
562	struct rdma_conn_param conn_param;
563	u32 version;
564	int err = 1, destroy = 1;
565
566	/* Check whether the remote protocol version matches ours. */
567	version = rds_ib_protocol_compatible(event);
568	if (!version)
569		goto out;
570
571	rdsdebug("saddr %pI4 daddr %pI4 RDSv%u.%u lguid 0x%llx fguid "
572		 "0x%llx\n", &dp->dp_saddr, &dp->dp_daddr,
573		 RDS_PROTOCOL_MAJOR(version), RDS_PROTOCOL_MINOR(version),
574		 (unsigned long long)be64_to_cpu(lguid),
575		 (unsigned long long)be64_to_cpu(fguid));
576
577	/* RDS/IB is not currently netns aware, thus init_net */
578	conn = rds_conn_create(&init_net, dp->dp_daddr, dp->dp_saddr,
579			       &rds_ib_transport, GFP_KERNEL);
580	if (IS_ERR(conn)) {
581		rdsdebug("rds_conn_create failed (%ld)\n", PTR_ERR(conn));
582		conn = NULL;
583		goto out;
584	}
585
586	/*
587	 * The connection request may occur while the
588	 * previous connection exist, e.g. in case of failover.
589	 * But as connections may be initiated simultaneously
590	 * by both hosts, we have a random backoff mechanism -
591	 * see the comment above rds_queue_reconnect()
592	 */
593	mutex_lock(&conn->c_cm_lock);
594	if (!rds_conn_transition(conn, RDS_CONN_DOWN, RDS_CONN_CONNECTING)) {
595		if (rds_conn_state(conn) == RDS_CONN_UP) {
596			rdsdebug("incoming connect while connecting\n");
597			rds_conn_drop(conn);
598			rds_ib_stats_inc(s_ib_listen_closed_stale);
599		} else
600		if (rds_conn_state(conn) == RDS_CONN_CONNECTING) {
601			/* Wait and see - our connect may still be succeeding */
602			rds_ib_stats_inc(s_ib_connect_raced);
603		}
604		goto out;
605	}
606
607	ic = conn->c_transport_data;
608
609	rds_ib_set_protocol(conn, version);
610	rds_ib_set_flow_control(conn, be32_to_cpu(dp->dp_credit));
611
612	/* If the peer gave us the last packet it saw, process this as if
613	 * we had received a regular ACK. */
614	if (dp->dp_ack_seq)
615		rds_send_drop_acked(conn, be64_to_cpu(dp->dp_ack_seq), NULL);
616
617	BUG_ON(cm_id->context);
618	BUG_ON(ic->i_cm_id);
619
620	ic->i_cm_id = cm_id;
621	cm_id->context = conn;
622
623	/* We got halfway through setting up the ib_connection, if we
624	 * fail now, we have to take the long route out of this mess. */
625	destroy = 0;
626
627	err = rds_ib_setup_qp(conn);
628	if (err) {
629		rds_ib_conn_error(conn, "rds_ib_setup_qp failed (%d)\n", err);
630		goto out;
631	}
632
633	rds_ib_cm_fill_conn_param(conn, &conn_param, &dp_rep, version,
634		event->param.conn.responder_resources,
635		event->param.conn.initiator_depth);
636
637	/* rdma_accept() calls rdma_reject() internally if it fails */
638	err = rdma_accept(cm_id, &conn_param);
639	if (err)
640		rds_ib_conn_error(conn, "rdma_accept failed (%d)\n", err);
641
642out:
643	if (conn)
644		mutex_unlock(&conn->c_cm_lock);
645	if (err)
646		rdma_reject(cm_id, NULL, 0);
647	return destroy;
648}
649
650
651int rds_ib_cm_initiate_connect(struct rdma_cm_id *cm_id)
652{
653	struct rds_connection *conn = cm_id->context;
654	struct rds_ib_connection *ic = conn->c_transport_data;
655	struct rdma_conn_param conn_param;
656	struct rds_ib_connect_private dp;
657	int ret;
658
659	/* If the peer doesn't do protocol negotiation, we must
660	 * default to RDSv3.0 */
661	rds_ib_set_protocol(conn, RDS_PROTOCOL_3_0);
662	ic->i_flowctl = rds_ib_sysctl_flow_control;	/* advertise flow control */
663
664	ret = rds_ib_setup_qp(conn);
665	if (ret) {
666		rds_ib_conn_error(conn, "rds_ib_setup_qp failed (%d)\n", ret);
667		goto out;
668	}
669
670	rds_ib_cm_fill_conn_param(conn, &conn_param, &dp, RDS_PROTOCOL_VERSION,
671		UINT_MAX, UINT_MAX);
672	ret = rdma_connect(cm_id, &conn_param);
673	if (ret)
674		rds_ib_conn_error(conn, "rdma_connect failed (%d)\n", ret);
675
676out:
677	/* Beware - returning non-zero tells the rdma_cm to destroy
678	 * the cm_id. We should certainly not do it as long as we still
679	 * "own" the cm_id. */
680	if (ret) {
681		if (ic->i_cm_id == cm_id)
682			ret = 0;
683	}
 
684	return ret;
685}
686
687int rds_ib_conn_connect(struct rds_connection *conn)
688{
 
689	struct rds_ib_connection *ic = conn->c_transport_data;
690	struct sockaddr_in src, dest;
691	int ret;
692
693	/* XXX I wonder what affect the port space has */
694	/* delegate cm event handler to rdma_transport */
695	ic->i_cm_id = rdma_create_id(&init_net, rds_rdma_cm_event_handler, conn,
696				     RDMA_PS_TCP, IB_QPT_RC);
697	if (IS_ERR(ic->i_cm_id)) {
698		ret = PTR_ERR(ic->i_cm_id);
699		ic->i_cm_id = NULL;
700		rdsdebug("rdma_create_id() failed: %d\n", ret);
701		goto out;
702	}
703
704	rdsdebug("created cm id %p for conn %p\n", ic->i_cm_id, conn);
705
706	src.sin_family = AF_INET;
707	src.sin_addr.s_addr = (__force u32)conn->c_laddr;
708	src.sin_port = (__force u16)htons(0);
709
710	dest.sin_family = AF_INET;
711	dest.sin_addr.s_addr = (__force u32)conn->c_faddr;
712	dest.sin_port = (__force u16)htons(RDS_PORT);
713
714	ret = rdma_resolve_addr(ic->i_cm_id, (struct sockaddr *)&src,
715				(struct sockaddr *)&dest,
716				RDS_RDMA_RESOLVE_TIMEOUT_MS);
717	if (ret) {
718		rdsdebug("addr resolve failed for cm id %p: %d\n", ic->i_cm_id,
719			 ret);
720		rdma_destroy_id(ic->i_cm_id);
721		ic->i_cm_id = NULL;
722	}
723
724out:
725	return ret;
726}
727
728/*
729 * This is so careful about only cleaning up resources that were built up
730 * so that it can be called at any point during startup.  In fact it
731 * can be called multiple times for a given connection.
732 */
733void rds_ib_conn_shutdown(struct rds_connection *conn)
734{
 
735	struct rds_ib_connection *ic = conn->c_transport_data;
736	int err = 0;
737
738	rdsdebug("cm %p pd %p cq %p %p qp %p\n", ic->i_cm_id,
739		 ic->i_pd, ic->i_send_cq, ic->i_recv_cq,
740		 ic->i_cm_id ? ic->i_cm_id->qp : NULL);
741
742	if (ic->i_cm_id) {
743		struct ib_device *dev = ic->i_cm_id->device;
744
745		rdsdebug("disconnecting cm %p\n", ic->i_cm_id);
746		err = rdma_disconnect(ic->i_cm_id);
747		if (err) {
748			/* Actually this may happen quite frequently, when
749			 * an outgoing connect raced with an incoming connect.
750			 */
751			rdsdebug("failed to disconnect, cm: %p err %d\n",
752				ic->i_cm_id, err);
753		}
754
755		/*
756		 * We want to wait for tx and rx completion to finish
757		 * before we tear down the connection, but we have to be
758		 * careful not to get stuck waiting on a send ring that
759		 * only has unsignaled sends in it.  We've shutdown new
760		 * sends before getting here so by waiting for signaled
761		 * sends to complete we're ensured that there will be no
762		 * more tx processing.
763		 */
764		wait_event(rds_ib_ring_empty_wait,
765			   rds_ib_ring_empty(&ic->i_recv_ring) &&
766			   (atomic_read(&ic->i_signaled_sends) == 0) &&
767			   (atomic_read(&ic->i_fastreg_wrs) == RDS_IB_DEFAULT_FR_WR));
 
768		tasklet_kill(&ic->i_send_tasklet);
769		tasklet_kill(&ic->i_recv_tasklet);
770
 
 
771		/* first destroy the ib state that generates callbacks */
772		if (ic->i_cm_id->qp)
773			rdma_destroy_qp(ic->i_cm_id);
774		if (ic->i_send_cq)
 
 
775			ib_destroy_cq(ic->i_send_cq);
776		if (ic->i_recv_cq)
 
 
 
 
777			ib_destroy_cq(ic->i_recv_cq);
 
778
779		/* then free the resources that ib callbacks use */
780		if (ic->i_send_hdrs)
781			ib_dma_free_coherent(dev,
782					   ic->i_send_ring.w_nr *
783						sizeof(struct rds_header),
784					   ic->i_send_hdrs,
785					   ic->i_send_hdrs_dma);
786
787		if (ic->i_recv_hdrs)
788			ib_dma_free_coherent(dev,
789					   ic->i_recv_ring.w_nr *
790						sizeof(struct rds_header),
791					   ic->i_recv_hdrs,
792					   ic->i_recv_hdrs_dma);
793
794		if (ic->i_ack)
795			ib_dma_free_coherent(dev, sizeof(struct rds_header),
796					     ic->i_ack, ic->i_ack_dma);
797
798		if (ic->i_sends)
799			rds_ib_send_clear_ring(ic);
800		if (ic->i_recvs)
801			rds_ib_recv_clear_ring(ic);
802
803		rdma_destroy_id(ic->i_cm_id);
804
805		/*
806		 * Move connection back to the nodev list.
807		 */
808		if (ic->rds_ibdev)
809			rds_ib_remove_conn(ic->rds_ibdev, conn);
810
811		ic->i_cm_id = NULL;
812		ic->i_pd = NULL;
813		ic->i_send_cq = NULL;
814		ic->i_recv_cq = NULL;
815		ic->i_send_hdrs = NULL;
816		ic->i_recv_hdrs = NULL;
817		ic->i_ack = NULL;
818	}
819	BUG_ON(ic->rds_ibdev);
820
821	/* Clear pending transmit */
822	if (ic->i_data_op) {
823		struct rds_message *rm;
824
825		rm = container_of(ic->i_data_op, struct rds_message, data);
826		rds_message_put(rm);
827		ic->i_data_op = NULL;
828	}
829
830	/* Clear the ACK state */
831	clear_bit(IB_ACK_IN_FLIGHT, &ic->i_ack_flags);
832#ifdef KERNEL_HAS_ATOMIC64
833	atomic64_set(&ic->i_ack_next, 0);
834#else
835	ic->i_ack_next = 0;
836#endif
837	ic->i_ack_recv = 0;
838
839	/* Clear flow control state */
840	ic->i_flowctl = 0;
841	atomic_set(&ic->i_credits, 0);
842
843	rds_ib_ring_init(&ic->i_send_ring, rds_ib_sysctl_max_send_wr);
844	rds_ib_ring_init(&ic->i_recv_ring, rds_ib_sysctl_max_recv_wr);
845
846	if (ic->i_ibinc) {
847		rds_inc_put(&ic->i_ibinc->ii_inc);
848		ic->i_ibinc = NULL;
849	}
850
851	vfree(ic->i_sends);
852	ic->i_sends = NULL;
853	vfree(ic->i_recvs);
854	ic->i_recvs = NULL;
 
855}
856
857int rds_ib_conn_alloc(struct rds_connection *conn, gfp_t gfp)
858{
859	struct rds_ib_connection *ic;
860	unsigned long flags;
861	int ret;
862
863	/* XXX too lazy? */
864	ic = kzalloc(sizeof(struct rds_ib_connection), gfp);
865	if (!ic)
866		return -ENOMEM;
867
868	ret = rds_ib_recv_alloc_caches(ic);
869	if (ret) {
870		kfree(ic);
871		return ret;
872	}
873
874	INIT_LIST_HEAD(&ic->ib_node);
875	tasklet_init(&ic->i_send_tasklet, rds_ib_tasklet_fn_send,
876		     (unsigned long)ic);
877	tasklet_init(&ic->i_recv_tasklet, rds_ib_tasklet_fn_recv,
878		     (unsigned long)ic);
879	mutex_init(&ic->i_recv_mutex);
880#ifndef KERNEL_HAS_ATOMIC64
881	spin_lock_init(&ic->i_ack_lock);
882#endif
883	atomic_set(&ic->i_signaled_sends, 0);
884
885	/*
886	 * rds_ib_conn_shutdown() waits for these to be emptied so they
887	 * must be initialized before it can be called.
888	 */
889	rds_ib_ring_init(&ic->i_send_ring, rds_ib_sysctl_max_send_wr);
890	rds_ib_ring_init(&ic->i_recv_ring, rds_ib_sysctl_max_recv_wr);
891
892	ic->conn = conn;
893	conn->c_transport_data = ic;
894
895	spin_lock_irqsave(&ib_nodev_conns_lock, flags);
896	list_add_tail(&ic->ib_node, &ib_nodev_conns);
897	spin_unlock_irqrestore(&ib_nodev_conns_lock, flags);
898
899
900	rdsdebug("conn %p conn ic %p\n", conn, conn->c_transport_data);
901	return 0;
902}
903
904/*
905 * Free a connection. Connection must be shut down and not set for reconnect.
906 */
907void rds_ib_conn_free(void *arg)
908{
909	struct rds_ib_connection *ic = arg;
910	spinlock_t	*lock_ptr;
911
912	rdsdebug("ic %p\n", ic);
913
914	/*
915	 * Conn is either on a dev's list or on the nodev list.
916	 * A race with shutdown() or connect() would cause problems
917	 * (since rds_ibdev would change) but that should never happen.
918	 */
919	lock_ptr = ic->rds_ibdev ? &ic->rds_ibdev->spinlock : &ib_nodev_conns_lock;
920
921	spin_lock_irq(lock_ptr);
922	list_del(&ic->ib_node);
923	spin_unlock_irq(lock_ptr);
924
925	rds_ib_recv_free_caches(ic);
926
927	kfree(ic);
928}
929
930
931/*
932 * An error occurred on the connection
933 */
934void
935__rds_ib_conn_error(struct rds_connection *conn, const char *fmt, ...)
936{
937	va_list ap;
938
939	rds_conn_drop(conn);
940
941	va_start(ap, fmt);
942	vprintk(fmt, ap);
943	va_end(ap);
944}
v4.17
   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		pr_notice("RDS/IB: Connection <%pI4,%pI4> version %u.%u no longer supported\n",
 117			  &conn->c_laddr, &conn->c_faddr,
 118			  RDS_PROTOCOL_MAJOR(conn->c_version),
 119			  RDS_PROTOCOL_MINOR(conn->c_version));
 120		set_bit(RDS_DESTROY_PENDING, &conn->c_path[0].cp_flags);
 121		rds_conn_destroy(conn);
 122		return;
 123	} else {
 124		pr_notice("RDS/IB: %s conn connected <%pI4,%pI4> version %u.%u%s\n",
 125			  ic->i_active_side ? "Active" : "Passive",
 126			  &conn->c_laddr, &conn->c_faddr,
 127			  RDS_PROTOCOL_MAJOR(conn->c_version),
 128			  RDS_PROTOCOL_MINOR(conn->c_version),
 129			  ic->i_flowctl ? ", flow control" : "");
 130	}
 131
 132	atomic_set(&ic->i_cq_quiesce, 0);
 133
 134	/* Init rings and fill recv. this needs to wait until protocol
 135	 * negotiation is complete, since ring layout is different
 136	 * from 3.1 to 4.1.
 137	 */
 138	rds_ib_send_init_ring(ic);
 139	rds_ib_recv_init_ring(ic);
 140	/* Post receive buffers - as a side effect, this will update
 141	 * the posted credit count. */
 142	rds_ib_recv_refill(conn, 1, GFP_KERNEL);
 143
 144	/* Tune RNR behavior */
 145	rds_ib_tune_rnr(ic, &qp_attr);
 146
 147	qp_attr.qp_state = IB_QPS_RTS;
 148	err = ib_modify_qp(ic->i_cm_id->qp, &qp_attr, IB_QP_STATE);
 149	if (err)
 150		printk(KERN_NOTICE "ib_modify_qp(IB_QP_STATE, RTS): err=%d\n", err);
 151
 152	/* update ib_device with this local ipaddr */
 153	err = rds_ib_update_ipaddr(ic->rds_ibdev, conn->c_laddr);
 154	if (err)
 155		printk(KERN_ERR "rds_ib_update_ipaddr failed (%d)\n",
 156			err);
 157
 158	/* If the peer gave us the last packet it saw, process this as if
 159	 * we had received a regular ACK. */
 160	if (dp) {
 161		/* dp structure start is not guaranteed to be 8 bytes aligned.
 162		 * Since dp_ack_seq is 64-bit extended load operations can be
 163		 * used so go through get_unaligned to avoid unaligned errors.
 164		 */
 165		__be64 dp_ack_seq = get_unaligned(&dp->dp_ack_seq);
 166
 167		if (dp_ack_seq)
 168			rds_send_drop_acked(conn, be64_to_cpu(dp_ack_seq),
 169					    NULL);
 170	}
 171
 172	rds_connect_complete(conn);
 173}
 174
 175static void rds_ib_cm_fill_conn_param(struct rds_connection *conn,
 176			struct rdma_conn_param *conn_param,
 177			struct rds_ib_connect_private *dp,
 178			u32 protocol_version,
 179			u32 max_responder_resources,
 180			u32 max_initiator_depth)
 181{
 182	struct rds_ib_connection *ic = conn->c_transport_data;
 183	struct rds_ib_device *rds_ibdev = ic->rds_ibdev;
 184
 185	memset(conn_param, 0, sizeof(struct rdma_conn_param));
 186
 187	conn_param->responder_resources =
 188		min_t(u32, rds_ibdev->max_responder_resources, max_responder_resources);
 189	conn_param->initiator_depth =
 190		min_t(u32, rds_ibdev->max_initiator_depth, max_initiator_depth);
 191	conn_param->retry_count = min_t(unsigned int, rds_ib_retry_count, 7);
 192	conn_param->rnr_retry_count = 7;
 193
 194	if (dp) {
 195		memset(dp, 0, sizeof(*dp));
 196		dp->dp_saddr = conn->c_laddr;
 197		dp->dp_daddr = conn->c_faddr;
 198		dp->dp_protocol_major = RDS_PROTOCOL_MAJOR(protocol_version);
 199		dp->dp_protocol_minor = RDS_PROTOCOL_MINOR(protocol_version);
 200		dp->dp_protocol_minor_mask = cpu_to_be16(RDS_IB_SUPPORTED_PROTOCOLS);
 201		dp->dp_ack_seq = cpu_to_be64(rds_ib_piggyb_ack(ic));
 202
 203		/* Advertise flow control */
 204		if (ic->i_flowctl) {
 205			unsigned int credits;
 206
 207			credits = IB_GET_POST_CREDITS(atomic_read(&ic->i_credits));
 208			dp->dp_credit = cpu_to_be32(credits);
 209			atomic_sub(IB_SET_POST_CREDITS(credits), &ic->i_credits);
 210		}
 211
 212		conn_param->private_data = dp;
 213		conn_param->private_data_len = sizeof(*dp);
 214	}
 215}
 216
 217static void rds_ib_cq_event_handler(struct ib_event *event, void *data)
 218{
 219	rdsdebug("event %u (%s) data %p\n",
 220		 event->event, ib_event_msg(event->event), data);
 221}
 222
 223/* Plucking the oldest entry from the ring can be done concurrently with
 224 * the thread refilling the ring.  Each ring operation is protected by
 225 * spinlocks and the transient state of refilling doesn't change the
 226 * recording of which entry is oldest.
 227 *
 228 * This relies on IB only calling one cq comp_handler for each cq so that
 229 * there will only be one caller of rds_recv_incoming() per RDS connection.
 230 */
 231static void rds_ib_cq_comp_handler_recv(struct ib_cq *cq, void *context)
 232{
 233	struct rds_connection *conn = context;
 234	struct rds_ib_connection *ic = conn->c_transport_data;
 235
 236	rdsdebug("conn %p cq %p\n", conn, cq);
 237
 238	rds_ib_stats_inc(s_ib_evt_handler_call);
 239
 240	tasklet_schedule(&ic->i_recv_tasklet);
 241}
 242
 243static void poll_scq(struct rds_ib_connection *ic, struct ib_cq *cq,
 244		     struct ib_wc *wcs)
 245{
 246	int nr, i;
 247	struct ib_wc *wc;
 248
 249	while ((nr = ib_poll_cq(cq, RDS_IB_WC_MAX, wcs)) > 0) {
 250		for (i = 0; i < nr; i++) {
 251			wc = wcs + i;
 252			rdsdebug("wc wr_id 0x%llx status %u byte_len %u imm_data %u\n",
 253				 (unsigned long long)wc->wr_id, wc->status,
 254				 wc->byte_len, be32_to_cpu(wc->ex.imm_data));
 255
 256			if (wc->wr_id <= ic->i_send_ring.w_nr ||
 257			    wc->wr_id == RDS_IB_ACK_WR_ID)
 258				rds_ib_send_cqe_handler(ic, wc);
 259			else
 260				rds_ib_mr_cqe_handler(ic, wc);
 261
 262		}
 263	}
 264}
 265
 266static void rds_ib_tasklet_fn_send(unsigned long data)
 267{
 268	struct rds_ib_connection *ic = (struct rds_ib_connection *)data;
 269	struct rds_connection *conn = ic->conn;
 270
 271	rds_ib_stats_inc(s_ib_tasklet_call);
 272
 273	/* if cq has been already reaped, ignore incoming cq event */
 274	if (atomic_read(&ic->i_cq_quiesce))
 275		return;
 276
 277	poll_scq(ic, ic->i_send_cq, ic->i_send_wc);
 278	ib_req_notify_cq(ic->i_send_cq, IB_CQ_NEXT_COMP);
 279	poll_scq(ic, ic->i_send_cq, ic->i_send_wc);
 280
 281	if (rds_conn_up(conn) &&
 282	    (!test_bit(RDS_LL_SEND_FULL, &conn->c_flags) ||
 283	    test_bit(0, &conn->c_map_queued)))
 284		rds_send_xmit(&ic->conn->c_path[0]);
 285}
 286
 287static void poll_rcq(struct rds_ib_connection *ic, struct ib_cq *cq,
 288		     struct ib_wc *wcs,
 289		     struct rds_ib_ack_state *ack_state)
 290{
 291	int nr, i;
 292	struct ib_wc *wc;
 293
 294	while ((nr = ib_poll_cq(cq, RDS_IB_WC_MAX, wcs)) > 0) {
 295		for (i = 0; i < nr; i++) {
 296			wc = wcs + i;
 297			rdsdebug("wc wr_id 0x%llx status %u byte_len %u imm_data %u\n",
 298				 (unsigned long long)wc->wr_id, wc->status,
 299				 wc->byte_len, be32_to_cpu(wc->ex.imm_data));
 300
 301			rds_ib_recv_cqe_handler(ic, wc, ack_state);
 302		}
 303	}
 304}
 305
 306static void rds_ib_tasklet_fn_recv(unsigned long data)
 307{
 308	struct rds_ib_connection *ic = (struct rds_ib_connection *)data;
 309	struct rds_connection *conn = ic->conn;
 310	struct rds_ib_device *rds_ibdev = ic->rds_ibdev;
 311	struct rds_ib_ack_state state;
 312
 313	if (!rds_ibdev)
 314		rds_conn_drop(conn);
 315
 316	rds_ib_stats_inc(s_ib_tasklet_call);
 317
 318	/* if cq has been already reaped, ignore incoming cq event */
 319	if (atomic_read(&ic->i_cq_quiesce))
 320		return;
 321
 322	memset(&state, 0, sizeof(state));
 323	poll_rcq(ic, ic->i_recv_cq, ic->i_recv_wc, &state);
 324	ib_req_notify_cq(ic->i_recv_cq, IB_CQ_SOLICITED);
 325	poll_rcq(ic, ic->i_recv_cq, ic->i_recv_wc, &state);
 326
 327	if (state.ack_next_valid)
 328		rds_ib_set_ack(ic, state.ack_next, state.ack_required);
 329	if (state.ack_recv_valid && state.ack_recv > ic->i_ack_recv) {
 330		rds_send_drop_acked(conn, state.ack_recv, NULL);
 331		ic->i_ack_recv = state.ack_recv;
 332	}
 333
 334	if (rds_conn_up(conn))
 335		rds_ib_attempt_ack(ic);
 336}
 337
 338static void rds_ib_qp_event_handler(struct ib_event *event, void *data)
 339{
 340	struct rds_connection *conn = data;
 341	struct rds_ib_connection *ic = conn->c_transport_data;
 342
 343	rdsdebug("conn %p ic %p event %u (%s)\n", conn, ic, event->event,
 344		 ib_event_msg(event->event));
 345
 346	switch (event->event) {
 347	case IB_EVENT_COMM_EST:
 348		rdma_notify(ic->i_cm_id, IB_EVENT_COMM_EST);
 349		break;
 350	default:
 351		rdsdebug("Fatal QP Event %u (%s) "
 352			"- connection %pI4->%pI4, reconnecting\n",
 353			event->event, ib_event_msg(event->event),
 354			&conn->c_laddr, &conn->c_faddr);
 355		rds_conn_drop(conn);
 356		break;
 357	}
 358}
 359
 360static void rds_ib_cq_comp_handler_send(struct ib_cq *cq, void *context)
 361{
 362	struct rds_connection *conn = context;
 363	struct rds_ib_connection *ic = conn->c_transport_data;
 364
 365	rdsdebug("conn %p cq %p\n", conn, cq);
 366
 367	rds_ib_stats_inc(s_ib_evt_handler_call);
 368
 369	tasklet_schedule(&ic->i_send_tasklet);
 370}
 371
 372static inline int ibdev_get_unused_vector(struct rds_ib_device *rds_ibdev)
 373{
 374	int min = rds_ibdev->vector_load[rds_ibdev->dev->num_comp_vectors - 1];
 375	int index = rds_ibdev->dev->num_comp_vectors - 1;
 376	int i;
 377
 378	for (i = rds_ibdev->dev->num_comp_vectors - 1; i >= 0; i--) {
 379		if (rds_ibdev->vector_load[i] < min) {
 380			index = i;
 381			min = rds_ibdev->vector_load[i];
 382		}
 383	}
 384
 385	rds_ibdev->vector_load[index]++;
 386	return index;
 387}
 388
 389static inline void ibdev_put_vector(struct rds_ib_device *rds_ibdev, int index)
 390{
 391	rds_ibdev->vector_load[index]--;
 392}
 393
 394/*
 395 * This needs to be very careful to not leave IS_ERR pointers around for
 396 * cleanup to trip over.
 397 */
 398static int rds_ib_setup_qp(struct rds_connection *conn)
 399{
 400	struct rds_ib_connection *ic = conn->c_transport_data;
 401	struct ib_device *dev = ic->i_cm_id->device;
 402	struct ib_qp_init_attr attr;
 403	struct ib_cq_init_attr cq_attr = {};
 404	struct rds_ib_device *rds_ibdev;
 405	int ret, fr_queue_space;
 406
 407	/*
 408	 * It's normal to see a null device if an incoming connection races
 409	 * with device removal, so we don't print a warning.
 410	 */
 411	rds_ibdev = rds_ib_get_client_data(dev);
 412	if (!rds_ibdev)
 413		return -EOPNOTSUPP;
 414
 415	/* The fr_queue_space is currently set to 512, to add extra space on
 416	 * completion queue and send queue. This extra space is used for FRMR
 417	 * registration and invalidation work requests
 418	 */
 419	fr_queue_space = rds_ibdev->use_fastreg ?
 420			 (RDS_IB_DEFAULT_FR_WR + 1) +
 421			 (RDS_IB_DEFAULT_FR_INV_WR + 1)
 422			 : 0;
 423
 424	/* add the conn now so that connection establishment has the dev */
 425	rds_ib_add_conn(rds_ibdev, conn);
 426
 427	if (rds_ibdev->max_wrs < ic->i_send_ring.w_nr + 1)
 428		rds_ib_ring_resize(&ic->i_send_ring, rds_ibdev->max_wrs - 1);
 429	if (rds_ibdev->max_wrs < ic->i_recv_ring.w_nr + 1)
 430		rds_ib_ring_resize(&ic->i_recv_ring, rds_ibdev->max_wrs - 1);
 431
 432	/* Protection domain and memory range */
 433	ic->i_pd = rds_ibdev->pd;
 434
 435	ic->i_scq_vector = ibdev_get_unused_vector(rds_ibdev);
 436	cq_attr.cqe = ic->i_send_ring.w_nr + fr_queue_space + 1;
 437	cq_attr.comp_vector = ic->i_scq_vector;
 438	ic->i_send_cq = ib_create_cq(dev, rds_ib_cq_comp_handler_send,
 439				     rds_ib_cq_event_handler, conn,
 440				     &cq_attr);
 441	if (IS_ERR(ic->i_send_cq)) {
 442		ret = PTR_ERR(ic->i_send_cq);
 443		ic->i_send_cq = NULL;
 444		ibdev_put_vector(rds_ibdev, ic->i_scq_vector);
 445		rdsdebug("ib_create_cq send failed: %d\n", ret);
 446		goto rds_ibdev_out;
 447	}
 448
 449	ic->i_rcq_vector = ibdev_get_unused_vector(rds_ibdev);
 450	cq_attr.cqe = ic->i_recv_ring.w_nr;
 451	cq_attr.comp_vector = ic->i_rcq_vector;
 452	ic->i_recv_cq = ib_create_cq(dev, rds_ib_cq_comp_handler_recv,
 453				     rds_ib_cq_event_handler, conn,
 454				     &cq_attr);
 455	if (IS_ERR(ic->i_recv_cq)) {
 456		ret = PTR_ERR(ic->i_recv_cq);
 457		ic->i_recv_cq = NULL;
 458		ibdev_put_vector(rds_ibdev, ic->i_rcq_vector);
 459		rdsdebug("ib_create_cq recv failed: %d\n", ret);
 460		goto send_cq_out;
 461	}
 462
 463	ret = ib_req_notify_cq(ic->i_send_cq, IB_CQ_NEXT_COMP);
 464	if (ret) {
 465		rdsdebug("ib_req_notify_cq send failed: %d\n", ret);
 466		goto recv_cq_out;
 467	}
 468
 469	ret = ib_req_notify_cq(ic->i_recv_cq, IB_CQ_SOLICITED);
 470	if (ret) {
 471		rdsdebug("ib_req_notify_cq recv failed: %d\n", ret);
 472		goto recv_cq_out;
 473	}
 474
 475	/* XXX negotiate max send/recv with remote? */
 476	memset(&attr, 0, sizeof(attr));
 477	attr.event_handler = rds_ib_qp_event_handler;
 478	attr.qp_context = conn;
 479	/* + 1 to allow for the single ack message */
 480	attr.cap.max_send_wr = ic->i_send_ring.w_nr + fr_queue_space + 1;
 481	attr.cap.max_recv_wr = ic->i_recv_ring.w_nr + 1;
 482	attr.cap.max_send_sge = rds_ibdev->max_sge;
 483	attr.cap.max_recv_sge = RDS_IB_RECV_SGE;
 484	attr.sq_sig_type = IB_SIGNAL_REQ_WR;
 485	attr.qp_type = IB_QPT_RC;
 486	attr.send_cq = ic->i_send_cq;
 487	attr.recv_cq = ic->i_recv_cq;
 488	atomic_set(&ic->i_fastreg_wrs, RDS_IB_DEFAULT_FR_WR);
 489	atomic_set(&ic->i_fastunreg_wrs, RDS_IB_DEFAULT_FR_INV_WR);
 490
 491	/*
 492	 * XXX this can fail if max_*_wr is too large?  Are we supposed
 493	 * to back off until we get a value that the hardware can support?
 494	 */
 495	ret = rdma_create_qp(ic->i_cm_id, ic->i_pd, &attr);
 496	if (ret) {
 497		rdsdebug("rdma_create_qp failed: %d\n", ret);
 498		goto recv_cq_out;
 499	}
 500
 501	ic->i_send_hdrs = ib_dma_alloc_coherent(dev,
 502					   ic->i_send_ring.w_nr *
 503						sizeof(struct rds_header),
 504					   &ic->i_send_hdrs_dma, GFP_KERNEL);
 505	if (!ic->i_send_hdrs) {
 506		ret = -ENOMEM;
 507		rdsdebug("ib_dma_alloc_coherent send failed\n");
 508		goto qp_out;
 509	}
 510
 511	ic->i_recv_hdrs = ib_dma_alloc_coherent(dev,
 512					   ic->i_recv_ring.w_nr *
 513						sizeof(struct rds_header),
 514					   &ic->i_recv_hdrs_dma, GFP_KERNEL);
 515	if (!ic->i_recv_hdrs) {
 516		ret = -ENOMEM;
 517		rdsdebug("ib_dma_alloc_coherent recv failed\n");
 518		goto send_hdrs_dma_out;
 519	}
 520
 521	ic->i_ack = ib_dma_alloc_coherent(dev, sizeof(struct rds_header),
 522				       &ic->i_ack_dma, GFP_KERNEL);
 523	if (!ic->i_ack) {
 524		ret = -ENOMEM;
 525		rdsdebug("ib_dma_alloc_coherent ack failed\n");
 526		goto recv_hdrs_dma_out;
 527	}
 528
 529	ic->i_sends = vzalloc_node(ic->i_send_ring.w_nr * sizeof(struct rds_ib_send_work),
 530				   ibdev_to_node(dev));
 531	if (!ic->i_sends) {
 532		ret = -ENOMEM;
 533		rdsdebug("send allocation failed\n");
 534		goto ack_dma_out;
 535	}
 536
 537	ic->i_recvs = vzalloc_node(ic->i_recv_ring.w_nr * sizeof(struct rds_ib_recv_work),
 538				   ibdev_to_node(dev));
 539	if (!ic->i_recvs) {
 540		ret = -ENOMEM;
 541		rdsdebug("recv allocation failed\n");
 542		goto sends_out;
 543	}
 544
 545	rds_ib_recv_init_ack(ic);
 546
 547	rdsdebug("conn %p pd %p cq %p %p\n", conn, ic->i_pd,
 548		 ic->i_send_cq, ic->i_recv_cq);
 549
 550	goto out;
 551
 552sends_out:
 553	vfree(ic->i_sends);
 554ack_dma_out:
 555	ib_dma_free_coherent(dev, sizeof(struct rds_header),
 556			     ic->i_ack, ic->i_ack_dma);
 557recv_hdrs_dma_out:
 558	ib_dma_free_coherent(dev, ic->i_recv_ring.w_nr *
 559					sizeof(struct rds_header),
 560					ic->i_recv_hdrs, ic->i_recv_hdrs_dma);
 561send_hdrs_dma_out:
 562	ib_dma_free_coherent(dev, ic->i_send_ring.w_nr *
 563					sizeof(struct rds_header),
 564					ic->i_send_hdrs, ic->i_send_hdrs_dma);
 565qp_out:
 566	rdma_destroy_qp(ic->i_cm_id);
 567recv_cq_out:
 568	if (!ib_destroy_cq(ic->i_recv_cq))
 569		ic->i_recv_cq = NULL;
 570send_cq_out:
 571	if (!ib_destroy_cq(ic->i_send_cq))
 572		ic->i_send_cq = NULL;
 573rds_ibdev_out:
 574	rds_ib_remove_conn(rds_ibdev, conn);
 575out:
 576	rds_ib_dev_put(rds_ibdev);
 577
 578	return ret;
 579}
 580
 581static u32 rds_ib_protocol_compatible(struct rdma_cm_event *event)
 582{
 583	const struct rds_ib_connect_private *dp = event->param.conn.private_data;
 584	u16 common;
 585	u32 version = 0;
 586
 587	/*
 588	 * rdma_cm private data is odd - when there is any private data in the
 589	 * request, we will be given a pretty large buffer without telling us the
 590	 * original size. The only way to tell the difference is by looking at
 591	 * the contents, which are initialized to zero.
 592	 * If the protocol version fields aren't set, this is a connection attempt
 593	 * from an older version. This could could be 3.0 or 2.0 - we can't tell.
 594	 * We really should have changed this for OFED 1.3 :-(
 595	 */
 596
 597	/* Be paranoid. RDS always has privdata */
 598	if (!event->param.conn.private_data_len) {
 599		printk(KERN_NOTICE "RDS incoming connection has no private data, "
 600			"rejecting\n");
 601		return 0;
 602	}
 603
 604	/* Even if len is crap *now* I still want to check it. -ASG */
 605	if (event->param.conn.private_data_len < sizeof (*dp) ||
 606	    dp->dp_protocol_major == 0)
 607		return RDS_PROTOCOL_3_0;
 608
 609	common = be16_to_cpu(dp->dp_protocol_minor_mask) & RDS_IB_SUPPORTED_PROTOCOLS;
 610	if (dp->dp_protocol_major == 3 && common) {
 611		version = RDS_PROTOCOL_3_0;
 612		while ((common >>= 1) != 0)
 613			version++;
 614	} else
 615		printk_ratelimited(KERN_NOTICE "RDS: Connection from %pI4 using incompatible protocol version %u.%u\n",
 616				&dp->dp_saddr,
 617				dp->dp_protocol_major,
 618				dp->dp_protocol_minor);
 619	return version;
 620}
 621
 622int rds_ib_cm_handle_connect(struct rdma_cm_id *cm_id,
 623				    struct rdma_cm_event *event)
 624{
 625	__be64 lguid = cm_id->route.path_rec->sgid.global.interface_id;
 626	__be64 fguid = cm_id->route.path_rec->dgid.global.interface_id;
 627	const struct rds_ib_connect_private *dp = event->param.conn.private_data;
 628	struct rds_ib_connect_private dp_rep;
 629	struct rds_connection *conn = NULL;
 630	struct rds_ib_connection *ic = NULL;
 631	struct rdma_conn_param conn_param;
 632	u32 version;
 633	int err = 1, destroy = 1;
 634
 635	/* Check whether the remote protocol version matches ours. */
 636	version = rds_ib_protocol_compatible(event);
 637	if (!version)
 638		goto out;
 639
 640	rdsdebug("saddr %pI4 daddr %pI4 RDSv%u.%u lguid 0x%llx fguid "
 641		 "0x%llx\n", &dp->dp_saddr, &dp->dp_daddr,
 642		 RDS_PROTOCOL_MAJOR(version), RDS_PROTOCOL_MINOR(version),
 643		 (unsigned long long)be64_to_cpu(lguid),
 644		 (unsigned long long)be64_to_cpu(fguid));
 645
 646	/* RDS/IB is not currently netns aware, thus init_net */
 647	conn = rds_conn_create(&init_net, dp->dp_daddr, dp->dp_saddr,
 648			       &rds_ib_transport, GFP_KERNEL);
 649	if (IS_ERR(conn)) {
 650		rdsdebug("rds_conn_create failed (%ld)\n", PTR_ERR(conn));
 651		conn = NULL;
 652		goto out;
 653	}
 654
 655	/*
 656	 * The connection request may occur while the
 657	 * previous connection exist, e.g. in case of failover.
 658	 * But as connections may be initiated simultaneously
 659	 * by both hosts, we have a random backoff mechanism -
 660	 * see the comment above rds_queue_reconnect()
 661	 */
 662	mutex_lock(&conn->c_cm_lock);
 663	if (!rds_conn_transition(conn, RDS_CONN_DOWN, RDS_CONN_CONNECTING)) {
 664		if (rds_conn_state(conn) == RDS_CONN_UP) {
 665			rdsdebug("incoming connect while connecting\n");
 666			rds_conn_drop(conn);
 667			rds_ib_stats_inc(s_ib_listen_closed_stale);
 668		} else
 669		if (rds_conn_state(conn) == RDS_CONN_CONNECTING) {
 670			/* Wait and see - our connect may still be succeeding */
 671			rds_ib_stats_inc(s_ib_connect_raced);
 672		}
 673		goto out;
 674	}
 675
 676	ic = conn->c_transport_data;
 677
 678	rds_ib_set_protocol(conn, version);
 679	rds_ib_set_flow_control(conn, be32_to_cpu(dp->dp_credit));
 680
 681	/* If the peer gave us the last packet it saw, process this as if
 682	 * we had received a regular ACK. */
 683	if (dp->dp_ack_seq)
 684		rds_send_drop_acked(conn, be64_to_cpu(dp->dp_ack_seq), NULL);
 685
 686	BUG_ON(cm_id->context);
 687	BUG_ON(ic->i_cm_id);
 688
 689	ic->i_cm_id = cm_id;
 690	cm_id->context = conn;
 691
 692	/* We got halfway through setting up the ib_connection, if we
 693	 * fail now, we have to take the long route out of this mess. */
 694	destroy = 0;
 695
 696	err = rds_ib_setup_qp(conn);
 697	if (err) {
 698		rds_ib_conn_error(conn, "rds_ib_setup_qp failed (%d)\n", err);
 699		goto out;
 700	}
 701
 702	rds_ib_cm_fill_conn_param(conn, &conn_param, &dp_rep, version,
 703		event->param.conn.responder_resources,
 704		event->param.conn.initiator_depth);
 705
 706	/* rdma_accept() calls rdma_reject() internally if it fails */
 707	if (rdma_accept(cm_id, &conn_param))
 708		rds_ib_conn_error(conn, "rdma_accept failed\n");
 
 709
 710out:
 711	if (conn)
 712		mutex_unlock(&conn->c_cm_lock);
 713	if (err)
 714		rdma_reject(cm_id, NULL, 0);
 715	return destroy;
 716}
 717
 718
 719int rds_ib_cm_initiate_connect(struct rdma_cm_id *cm_id)
 720{
 721	struct rds_connection *conn = cm_id->context;
 722	struct rds_ib_connection *ic = conn->c_transport_data;
 723	struct rdma_conn_param conn_param;
 724	struct rds_ib_connect_private dp;
 725	int ret;
 726
 727	/* If the peer doesn't do protocol negotiation, we must
 728	 * default to RDSv3.0 */
 729	rds_ib_set_protocol(conn, RDS_PROTOCOL_3_0);
 730	ic->i_flowctl = rds_ib_sysctl_flow_control;	/* advertise flow control */
 731
 732	ret = rds_ib_setup_qp(conn);
 733	if (ret) {
 734		rds_ib_conn_error(conn, "rds_ib_setup_qp failed (%d)\n", ret);
 735		goto out;
 736	}
 737
 738	rds_ib_cm_fill_conn_param(conn, &conn_param, &dp, RDS_PROTOCOL_VERSION,
 739		UINT_MAX, UINT_MAX);
 740	ret = rdma_connect(cm_id, &conn_param);
 741	if (ret)
 742		rds_ib_conn_error(conn, "rdma_connect failed (%d)\n", ret);
 743
 744out:
 745	/* Beware - returning non-zero tells the rdma_cm to destroy
 746	 * the cm_id. We should certainly not do it as long as we still
 747	 * "own" the cm_id. */
 748	if (ret) {
 749		if (ic->i_cm_id == cm_id)
 750			ret = 0;
 751	}
 752	ic->i_active_side = true;
 753	return ret;
 754}
 755
 756int rds_ib_conn_path_connect(struct rds_conn_path *cp)
 757{
 758	struct rds_connection *conn = cp->cp_conn;
 759	struct rds_ib_connection *ic = conn->c_transport_data;
 760	struct sockaddr_in src, dest;
 761	int ret;
 762
 763	/* XXX I wonder what affect the port space has */
 764	/* delegate cm event handler to rdma_transport */
 765	ic->i_cm_id = rdma_create_id(&init_net, rds_rdma_cm_event_handler, conn,
 766				     RDMA_PS_TCP, IB_QPT_RC);
 767	if (IS_ERR(ic->i_cm_id)) {
 768		ret = PTR_ERR(ic->i_cm_id);
 769		ic->i_cm_id = NULL;
 770		rdsdebug("rdma_create_id() failed: %d\n", ret);
 771		goto out;
 772	}
 773
 774	rdsdebug("created cm id %p for conn %p\n", ic->i_cm_id, conn);
 775
 776	src.sin_family = AF_INET;
 777	src.sin_addr.s_addr = (__force u32)conn->c_laddr;
 778	src.sin_port = (__force u16)htons(0);
 779
 780	dest.sin_family = AF_INET;
 781	dest.sin_addr.s_addr = (__force u32)conn->c_faddr;
 782	dest.sin_port = (__force u16)htons(RDS_PORT);
 783
 784	ret = rdma_resolve_addr(ic->i_cm_id, (struct sockaddr *)&src,
 785				(struct sockaddr *)&dest,
 786				RDS_RDMA_RESOLVE_TIMEOUT_MS);
 787	if (ret) {
 788		rdsdebug("addr resolve failed for cm id %p: %d\n", ic->i_cm_id,
 789			 ret);
 790		rdma_destroy_id(ic->i_cm_id);
 791		ic->i_cm_id = NULL;
 792	}
 793
 794out:
 795	return ret;
 796}
 797
 798/*
 799 * This is so careful about only cleaning up resources that were built up
 800 * so that it can be called at any point during startup.  In fact it
 801 * can be called multiple times for a given connection.
 802 */
 803void rds_ib_conn_path_shutdown(struct rds_conn_path *cp)
 804{
 805	struct rds_connection *conn = cp->cp_conn;
 806	struct rds_ib_connection *ic = conn->c_transport_data;
 807	int err = 0;
 808
 809	rdsdebug("cm %p pd %p cq %p %p qp %p\n", ic->i_cm_id,
 810		 ic->i_pd, ic->i_send_cq, ic->i_recv_cq,
 811		 ic->i_cm_id ? ic->i_cm_id->qp : NULL);
 812
 813	if (ic->i_cm_id) {
 814		struct ib_device *dev = ic->i_cm_id->device;
 815
 816		rdsdebug("disconnecting cm %p\n", ic->i_cm_id);
 817		err = rdma_disconnect(ic->i_cm_id);
 818		if (err) {
 819			/* Actually this may happen quite frequently, when
 820			 * an outgoing connect raced with an incoming connect.
 821			 */
 822			rdsdebug("failed to disconnect, cm: %p err %d\n",
 823				ic->i_cm_id, err);
 824		}
 825
 826		/*
 827		 * We want to wait for tx and rx completion to finish
 828		 * before we tear down the connection, but we have to be
 829		 * careful not to get stuck waiting on a send ring that
 830		 * only has unsignaled sends in it.  We've shutdown new
 831		 * sends before getting here so by waiting for signaled
 832		 * sends to complete we're ensured that there will be no
 833		 * more tx processing.
 834		 */
 835		wait_event(rds_ib_ring_empty_wait,
 836			   rds_ib_ring_empty(&ic->i_recv_ring) &&
 837			   (atomic_read(&ic->i_signaled_sends) == 0) &&
 838			   (atomic_read(&ic->i_fastreg_wrs) == RDS_IB_DEFAULT_FR_WR) &&
 839			   (atomic_read(&ic->i_fastunreg_wrs) == RDS_IB_DEFAULT_FR_INV_WR));
 840		tasklet_kill(&ic->i_send_tasklet);
 841		tasklet_kill(&ic->i_recv_tasklet);
 842
 843		atomic_set(&ic->i_cq_quiesce, 1);
 844
 845		/* first destroy the ib state that generates callbacks */
 846		if (ic->i_cm_id->qp)
 847			rdma_destroy_qp(ic->i_cm_id);
 848		if (ic->i_send_cq) {
 849			if (ic->rds_ibdev)
 850				ibdev_put_vector(ic->rds_ibdev, ic->i_scq_vector);
 851			ib_destroy_cq(ic->i_send_cq);
 852		}
 853
 854		if (ic->i_recv_cq) {
 855			if (ic->rds_ibdev)
 856				ibdev_put_vector(ic->rds_ibdev, ic->i_rcq_vector);
 857			ib_destroy_cq(ic->i_recv_cq);
 858		}
 859
 860		/* then free the resources that ib callbacks use */
 861		if (ic->i_send_hdrs)
 862			ib_dma_free_coherent(dev,
 863					   ic->i_send_ring.w_nr *
 864						sizeof(struct rds_header),
 865					   ic->i_send_hdrs,
 866					   ic->i_send_hdrs_dma);
 867
 868		if (ic->i_recv_hdrs)
 869			ib_dma_free_coherent(dev,
 870					   ic->i_recv_ring.w_nr *
 871						sizeof(struct rds_header),
 872					   ic->i_recv_hdrs,
 873					   ic->i_recv_hdrs_dma);
 874
 875		if (ic->i_ack)
 876			ib_dma_free_coherent(dev, sizeof(struct rds_header),
 877					     ic->i_ack, ic->i_ack_dma);
 878
 879		if (ic->i_sends)
 880			rds_ib_send_clear_ring(ic);
 881		if (ic->i_recvs)
 882			rds_ib_recv_clear_ring(ic);
 883
 884		rdma_destroy_id(ic->i_cm_id);
 885
 886		/*
 887		 * Move connection back to the nodev list.
 888		 */
 889		if (ic->rds_ibdev)
 890			rds_ib_remove_conn(ic->rds_ibdev, conn);
 891
 892		ic->i_cm_id = NULL;
 893		ic->i_pd = NULL;
 894		ic->i_send_cq = NULL;
 895		ic->i_recv_cq = NULL;
 896		ic->i_send_hdrs = NULL;
 897		ic->i_recv_hdrs = NULL;
 898		ic->i_ack = NULL;
 899	}
 900	BUG_ON(ic->rds_ibdev);
 901
 902	/* Clear pending transmit */
 903	if (ic->i_data_op) {
 904		struct rds_message *rm;
 905
 906		rm = container_of(ic->i_data_op, struct rds_message, data);
 907		rds_message_put(rm);
 908		ic->i_data_op = NULL;
 909	}
 910
 911	/* Clear the ACK state */
 912	clear_bit(IB_ACK_IN_FLIGHT, &ic->i_ack_flags);
 913#ifdef KERNEL_HAS_ATOMIC64
 914	atomic64_set(&ic->i_ack_next, 0);
 915#else
 916	ic->i_ack_next = 0;
 917#endif
 918	ic->i_ack_recv = 0;
 919
 920	/* Clear flow control state */
 921	ic->i_flowctl = 0;
 922	atomic_set(&ic->i_credits, 0);
 923
 924	rds_ib_ring_init(&ic->i_send_ring, rds_ib_sysctl_max_send_wr);
 925	rds_ib_ring_init(&ic->i_recv_ring, rds_ib_sysctl_max_recv_wr);
 926
 927	if (ic->i_ibinc) {
 928		rds_inc_put(&ic->i_ibinc->ii_inc);
 929		ic->i_ibinc = NULL;
 930	}
 931
 932	vfree(ic->i_sends);
 933	ic->i_sends = NULL;
 934	vfree(ic->i_recvs);
 935	ic->i_recvs = NULL;
 936	ic->i_active_side = false;
 937}
 938
 939int rds_ib_conn_alloc(struct rds_connection *conn, gfp_t gfp)
 940{
 941	struct rds_ib_connection *ic;
 942	unsigned long flags;
 943	int ret;
 944
 945	/* XXX too lazy? */
 946	ic = kzalloc(sizeof(struct rds_ib_connection), gfp);
 947	if (!ic)
 948		return -ENOMEM;
 949
 950	ret = rds_ib_recv_alloc_caches(ic);
 951	if (ret) {
 952		kfree(ic);
 953		return ret;
 954	}
 955
 956	INIT_LIST_HEAD(&ic->ib_node);
 957	tasklet_init(&ic->i_send_tasklet, rds_ib_tasklet_fn_send,
 958		     (unsigned long)ic);
 959	tasklet_init(&ic->i_recv_tasklet, rds_ib_tasklet_fn_recv,
 960		     (unsigned long)ic);
 961	mutex_init(&ic->i_recv_mutex);
 962#ifndef KERNEL_HAS_ATOMIC64
 963	spin_lock_init(&ic->i_ack_lock);
 964#endif
 965	atomic_set(&ic->i_signaled_sends, 0);
 966
 967	/*
 968	 * rds_ib_conn_shutdown() waits for these to be emptied so they
 969	 * must be initialized before it can be called.
 970	 */
 971	rds_ib_ring_init(&ic->i_send_ring, rds_ib_sysctl_max_send_wr);
 972	rds_ib_ring_init(&ic->i_recv_ring, rds_ib_sysctl_max_recv_wr);
 973
 974	ic->conn = conn;
 975	conn->c_transport_data = ic;
 976
 977	spin_lock_irqsave(&ib_nodev_conns_lock, flags);
 978	list_add_tail(&ic->ib_node, &ib_nodev_conns);
 979	spin_unlock_irqrestore(&ib_nodev_conns_lock, flags);
 980
 981
 982	rdsdebug("conn %p conn ic %p\n", conn, conn->c_transport_data);
 983	return 0;
 984}
 985
 986/*
 987 * Free a connection. Connection must be shut down and not set for reconnect.
 988 */
 989void rds_ib_conn_free(void *arg)
 990{
 991	struct rds_ib_connection *ic = arg;
 992	spinlock_t	*lock_ptr;
 993
 994	rdsdebug("ic %p\n", ic);
 995
 996	/*
 997	 * Conn is either on a dev's list or on the nodev list.
 998	 * A race with shutdown() or connect() would cause problems
 999	 * (since rds_ibdev would change) but that should never happen.
1000	 */
1001	lock_ptr = ic->rds_ibdev ? &ic->rds_ibdev->spinlock : &ib_nodev_conns_lock;
1002
1003	spin_lock_irq(lock_ptr);
1004	list_del(&ic->ib_node);
1005	spin_unlock_irq(lock_ptr);
1006
1007	rds_ib_recv_free_caches(ic);
1008
1009	kfree(ic);
1010}
1011
1012
1013/*
1014 * An error occurred on the connection
1015 */
1016void
1017__rds_ib_conn_error(struct rds_connection *conn, const char *fmt, ...)
1018{
1019	va_list ap;
1020
1021	rds_conn_drop(conn);
1022
1023	va_start(ap, fmt);
1024	vprintk(fmt, ap);
1025	va_end(ap);
1026}