2 * Copyright (c) 2006 Oracle. All rights reserved.
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:
10 * Redistribution and use in source and binary forms, with or
11 * without modification, are permitted provided that the following
14 * - Redistributions of source code must retain the above
15 * copyright notice, this list of conditions and the following
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.
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
33 #include <linux/kernel.h>
35 #include <linux/slab.h>
36 #include <linux/vmalloc.h>
37 #include <linux/ratelimit.h>
43 * Set the selected protocol version
45 static void rds_ib_set_protocol(struct rds_connection *conn, unsigned int version)
47 conn->c_version = version;
53 static void rds_ib_set_flow_control(struct rds_connection *conn, u32 credits)
55 struct rds_ib_connection *ic = conn->c_transport_data;
57 if (rds_ib_sysctl_flow_control && credits != 0) {
58 /* We're doing flow control */
60 rds_ib_send_add_credits(conn, credits);
67 * Tune RNR behavior. Without flow control, we use a rather
68 * low timeout, but not the absolute minimum - this should
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
77 * Caller passes in a qp_attr pointer - don't waste stack spacv
78 * by allocation this twice.
81 rds_ib_tune_rnr(struct rds_ib_connection *ic, struct ib_qp_attr *attr)
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);
88 printk(KERN_NOTICE "ib_modify_qp(IB_QP_MIN_RNR_TIMER): err=%d\n", -ret);
92 * Connection established.
93 * We get here for both outgoing and incoming connection.
95 void rds_ib_cm_connect_complete(struct rds_connection *conn, struct rdma_cm_event *event)
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;
102 if (event->param.conn.private_data_len >= sizeof(*dp)) {
103 dp = event->param.conn.private_data;
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));
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",
118 RDS_PROTOCOL_MAJOR(conn->c_version),
119 RDS_PROTOCOL_MINOR(conn->c_version));
120 rds_conn_destroy(conn);
123 printk(KERN_NOTICE "RDS/IB: connected to %pI4 version %u.%u%s\n",
125 RDS_PROTOCOL_MAJOR(conn->c_version),
126 RDS_PROTOCOL_MINOR(conn->c_version),
127 ic->i_flowctl ? ", flow control" : "");
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.
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);
140 /* Tune RNR behavior */
141 rds_ib_tune_rnr(ic, &qp_attr);
143 qp_attr.qp_state = IB_QPS_RTS;
144 err = ib_modify_qp(ic->i_cm_id->qp, &qp_attr, IB_QP_STATE);
146 printk(KERN_NOTICE "ib_modify_qp(IB_QP_STATE, RTS): err=%d\n", err);
148 /* update ib_device with this local ipaddr */
149 err = rds_ib_update_ipaddr(ic->rds_ibdev, conn->c_laddr);
151 printk(KERN_ERR "rds_ib_update_ipaddr failed (%d)\n",
154 /* If the peer gave us the last packet it saw, process this as if
155 * we had received a regular ACK. */
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.
161 __be64 dp_ack_seq = get_unaligned(&dp->dp_ack_seq);
164 rds_send_drop_acked(conn, be64_to_cpu(dp_ack_seq),
168 rds_connect_complete(conn);
171 static 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)
178 struct rds_ib_connection *ic = conn->c_transport_data;
179 struct rds_ib_device *rds_ibdev = ic->rds_ibdev;
181 memset(conn_param, 0, sizeof(struct rdma_conn_param));
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;
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 = rds_ib_piggyb_ack(ic);
199 /* Advertise flow control */
201 unsigned int credits;
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);
208 conn_param->private_data = dp;
209 conn_param->private_data_len = sizeof(*dp);
213 static void rds_ib_cq_event_handler(struct ib_event *event, void *data)
215 rdsdebug("event %u (%s) data %p\n",
216 event->event, ib_event_msg(event->event), data);
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.
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.
227 static void rds_ib_cq_comp_handler_recv(struct ib_cq *cq, void *context)
229 struct rds_connection *conn = context;
230 struct rds_ib_connection *ic = conn->c_transport_data;
232 rdsdebug("conn %p cq %p\n", conn, cq);
234 rds_ib_stats_inc(s_ib_evt_handler_call);
236 tasklet_schedule(&ic->i_recv_tasklet);
239 static void poll_cq(struct rds_ib_connection *ic, struct ib_cq *cq,
241 struct rds_ib_ack_state *ack_state)
247 while ((nr = ib_poll_cq(cq, RDS_IB_WC_MAX, wcs)) > 0) {
248 for (i = 0; i < nr; i++) {
250 rdsdebug("wc wr_id 0x%llx status %u byte_len %u imm_data %u\n",
251 (unsigned long long)wc->wr_id, wc->status,
252 wc->byte_len, be32_to_cpu(wc->ex.imm_data));
254 if (wc->wr_id & RDS_IB_SEND_OP)
255 rds_ib_send_cqe_handler(ic, wc);
257 rds_ib_recv_cqe_handler(ic, wc, ack_state);
262 static void rds_ib_tasklet_fn_send(unsigned long data)
264 struct rds_ib_connection *ic = (struct rds_ib_connection *)data;
265 struct rds_connection *conn = ic->conn;
266 struct rds_ib_ack_state state;
268 rds_ib_stats_inc(s_ib_tasklet_call);
270 memset(&state, 0, sizeof(state));
271 poll_cq(ic, ic->i_send_cq, ic->i_send_wc, &state);
272 ib_req_notify_cq(ic->i_send_cq, IB_CQ_NEXT_COMP);
273 poll_cq(ic, ic->i_send_cq, ic->i_send_wc, &state);
275 if (rds_conn_up(conn) &&
276 (!test_bit(RDS_LL_SEND_FULL, &conn->c_flags) ||
277 test_bit(0, &conn->c_map_queued)))
278 rds_send_xmit(ic->conn);
281 static void rds_ib_tasklet_fn_recv(unsigned long data)
283 struct rds_ib_connection *ic = (struct rds_ib_connection *)data;
284 struct rds_connection *conn = ic->conn;
285 struct rds_ib_device *rds_ibdev = ic->rds_ibdev;
286 struct rds_ib_ack_state state;
290 rds_ib_stats_inc(s_ib_tasklet_call);
292 memset(&state, 0, sizeof(state));
293 poll_cq(ic, ic->i_recv_cq, ic->i_recv_wc, &state);
294 ib_req_notify_cq(ic->i_recv_cq, IB_CQ_SOLICITED);
295 poll_cq(ic, ic->i_recv_cq, ic->i_recv_wc, &state);
297 if (state.ack_next_valid)
298 rds_ib_set_ack(ic, state.ack_next, state.ack_required);
299 if (state.ack_recv_valid && state.ack_recv > ic->i_ack_recv) {
300 rds_send_drop_acked(conn, state.ack_recv, NULL);
301 ic->i_ack_recv = state.ack_recv;
304 if (rds_conn_up(conn))
305 rds_ib_attempt_ack(ic);
308 static void rds_ib_qp_event_handler(struct ib_event *event, void *data)
310 struct rds_connection *conn = data;
311 struct rds_ib_connection *ic = conn->c_transport_data;
313 rdsdebug("conn %p ic %p event %u (%s)\n", conn, ic, event->event,
314 ib_event_msg(event->event));
316 switch (event->event) {
317 case IB_EVENT_COMM_EST:
318 rdma_notify(ic->i_cm_id, IB_EVENT_COMM_EST);
321 rdsdebug("Fatal QP Event %u (%s) "
322 "- connection %pI4->%pI4, reconnecting\n",
323 event->event, ib_event_msg(event->event),
324 &conn->c_laddr, &conn->c_faddr);
330 static void rds_ib_cq_comp_handler_send(struct ib_cq *cq, void *context)
332 struct rds_connection *conn = context;
333 struct rds_ib_connection *ic = conn->c_transport_data;
335 rdsdebug("conn %p cq %p\n", conn, cq);
337 rds_ib_stats_inc(s_ib_evt_handler_call);
339 tasklet_schedule(&ic->i_send_tasklet);
343 * This needs to be very careful to not leave IS_ERR pointers around for
344 * cleanup to trip over.
346 static int rds_ib_setup_qp(struct rds_connection *conn)
348 struct rds_ib_connection *ic = conn->c_transport_data;
349 struct ib_device *dev = ic->i_cm_id->device;
350 struct ib_qp_init_attr attr;
351 struct ib_cq_init_attr cq_attr = {};
352 struct rds_ib_device *rds_ibdev;
356 * It's normal to see a null device if an incoming connection races
357 * with device removal, so we don't print a warning.
359 rds_ibdev = rds_ib_get_client_data(dev);
363 /* add the conn now so that connection establishment has the dev */
364 rds_ib_add_conn(rds_ibdev, conn);
366 if (rds_ibdev->max_wrs < ic->i_send_ring.w_nr + 1)
367 rds_ib_ring_resize(&ic->i_send_ring, rds_ibdev->max_wrs - 1);
368 if (rds_ibdev->max_wrs < ic->i_recv_ring.w_nr + 1)
369 rds_ib_ring_resize(&ic->i_recv_ring, rds_ibdev->max_wrs - 1);
371 /* Protection domain and memory range */
372 ic->i_pd = rds_ibdev->pd;
374 cq_attr.cqe = ic->i_send_ring.w_nr + 1;
376 ic->i_send_cq = ib_create_cq(dev, rds_ib_cq_comp_handler_send,
377 rds_ib_cq_event_handler, conn,
379 if (IS_ERR(ic->i_send_cq)) {
380 ret = PTR_ERR(ic->i_send_cq);
381 ic->i_send_cq = NULL;
382 rdsdebug("ib_create_cq send failed: %d\n", ret);
386 cq_attr.cqe = ic->i_recv_ring.w_nr;
387 ic->i_recv_cq = ib_create_cq(dev, rds_ib_cq_comp_handler_recv,
388 rds_ib_cq_event_handler, conn,
390 if (IS_ERR(ic->i_recv_cq)) {
391 ret = PTR_ERR(ic->i_recv_cq);
392 ic->i_recv_cq = NULL;
393 rdsdebug("ib_create_cq recv failed: %d\n", ret);
397 ret = ib_req_notify_cq(ic->i_send_cq, IB_CQ_NEXT_COMP);
399 rdsdebug("ib_req_notify_cq send failed: %d\n", ret);
403 ret = ib_req_notify_cq(ic->i_recv_cq, IB_CQ_SOLICITED);
405 rdsdebug("ib_req_notify_cq recv failed: %d\n", ret);
409 /* XXX negotiate max send/recv with remote? */
410 memset(&attr, 0, sizeof(attr));
411 attr.event_handler = rds_ib_qp_event_handler;
412 attr.qp_context = conn;
413 /* + 1 to allow for the single ack message */
414 attr.cap.max_send_wr = ic->i_send_ring.w_nr + 1;
415 attr.cap.max_recv_wr = ic->i_recv_ring.w_nr + 1;
416 attr.cap.max_send_sge = rds_ibdev->max_sge;
417 attr.cap.max_recv_sge = RDS_IB_RECV_SGE;
418 attr.sq_sig_type = IB_SIGNAL_REQ_WR;
419 attr.qp_type = IB_QPT_RC;
420 attr.send_cq = ic->i_send_cq;
421 attr.recv_cq = ic->i_recv_cq;
424 * XXX this can fail if max_*_wr is too large? Are we supposed
425 * to back off until we get a value that the hardware can support?
427 ret = rdma_create_qp(ic->i_cm_id, ic->i_pd, &attr);
429 rdsdebug("rdma_create_qp failed: %d\n", ret);
433 ic->i_send_hdrs = ib_dma_alloc_coherent(dev,
434 ic->i_send_ring.w_nr *
435 sizeof(struct rds_header),
436 &ic->i_send_hdrs_dma, GFP_KERNEL);
437 if (!ic->i_send_hdrs) {
439 rdsdebug("ib_dma_alloc_coherent send failed\n");
443 ic->i_recv_hdrs = ib_dma_alloc_coherent(dev,
444 ic->i_recv_ring.w_nr *
445 sizeof(struct rds_header),
446 &ic->i_recv_hdrs_dma, GFP_KERNEL);
447 if (!ic->i_recv_hdrs) {
449 rdsdebug("ib_dma_alloc_coherent recv failed\n");
453 ic->i_ack = ib_dma_alloc_coherent(dev, sizeof(struct rds_header),
454 &ic->i_ack_dma, GFP_KERNEL);
457 rdsdebug("ib_dma_alloc_coherent ack failed\n");
461 ic->i_sends = vzalloc_node(ic->i_send_ring.w_nr * sizeof(struct rds_ib_send_work),
465 rdsdebug("send allocation failed\n");
469 ic->i_recvs = vzalloc_node(ic->i_recv_ring.w_nr * sizeof(struct rds_ib_recv_work),
473 rdsdebug("recv allocation failed\n");
477 rds_ib_recv_init_ack(ic);
479 rdsdebug("conn %p pd %p cq %p %p\n", conn, ic->i_pd,
480 ic->i_send_cq, ic->i_recv_cq);
483 rds_ib_dev_put(rds_ibdev);
487 static u32 rds_ib_protocol_compatible(struct rdma_cm_event *event)
489 const struct rds_ib_connect_private *dp = event->param.conn.private_data;
494 * rdma_cm private data is odd - when there is any private data in the
495 * request, we will be given a pretty large buffer without telling us the
496 * original size. The only way to tell the difference is by looking at
497 * the contents, which are initialized to zero.
498 * If the protocol version fields aren't set, this is a connection attempt
499 * from an older version. This could could be 3.0 or 2.0 - we can't tell.
500 * We really should have changed this for OFED 1.3 :-(
503 /* Be paranoid. RDS always has privdata */
504 if (!event->param.conn.private_data_len) {
505 printk(KERN_NOTICE "RDS incoming connection has no private data, "
510 /* Even if len is crap *now* I still want to check it. -ASG */
511 if (event->param.conn.private_data_len < sizeof (*dp) ||
512 dp->dp_protocol_major == 0)
513 return RDS_PROTOCOL_3_0;
515 common = be16_to_cpu(dp->dp_protocol_minor_mask) & RDS_IB_SUPPORTED_PROTOCOLS;
516 if (dp->dp_protocol_major == 3 && common) {
517 version = RDS_PROTOCOL_3_0;
518 while ((common >>= 1) != 0)
521 printk_ratelimited(KERN_NOTICE "RDS: Connection from %pI4 using incompatible protocol version %u.%u\n",
523 dp->dp_protocol_major,
524 dp->dp_protocol_minor);
528 int rds_ib_cm_handle_connect(struct rdma_cm_id *cm_id,
529 struct rdma_cm_event *event)
531 __be64 lguid = cm_id->route.path_rec->sgid.global.interface_id;
532 __be64 fguid = cm_id->route.path_rec->dgid.global.interface_id;
533 const struct rds_ib_connect_private *dp = event->param.conn.private_data;
534 struct rds_ib_connect_private dp_rep;
535 struct rds_connection *conn = NULL;
536 struct rds_ib_connection *ic = NULL;
537 struct rdma_conn_param conn_param;
539 int err = 1, destroy = 1;
541 /* Check whether the remote protocol version matches ours. */
542 version = rds_ib_protocol_compatible(event);
546 rdsdebug("saddr %pI4 daddr %pI4 RDSv%u.%u lguid 0x%llx fguid "
547 "0x%llx\n", &dp->dp_saddr, &dp->dp_daddr,
548 RDS_PROTOCOL_MAJOR(version), RDS_PROTOCOL_MINOR(version),
549 (unsigned long long)be64_to_cpu(lguid),
550 (unsigned long long)be64_to_cpu(fguid));
552 /* RDS/IB is not currently netns aware, thus init_net */
553 conn = rds_conn_create(&init_net, dp->dp_daddr, dp->dp_saddr,
554 &rds_ib_transport, GFP_KERNEL);
556 rdsdebug("rds_conn_create failed (%ld)\n", PTR_ERR(conn));
562 * The connection request may occur while the
563 * previous connection exist, e.g. in case of failover.
564 * But as connections may be initiated simultaneously
565 * by both hosts, we have a random backoff mechanism -
566 * see the comment above rds_queue_reconnect()
568 mutex_lock(&conn->c_cm_lock);
569 if (!rds_conn_transition(conn, RDS_CONN_DOWN, RDS_CONN_CONNECTING)) {
570 if (rds_conn_state(conn) == RDS_CONN_UP) {
571 rdsdebug("incoming connect while connecting\n");
573 rds_ib_stats_inc(s_ib_listen_closed_stale);
575 if (rds_conn_state(conn) == RDS_CONN_CONNECTING) {
576 /* Wait and see - our connect may still be succeeding */
577 rds_ib_stats_inc(s_ib_connect_raced);
582 ic = conn->c_transport_data;
584 rds_ib_set_protocol(conn, version);
585 rds_ib_set_flow_control(conn, be32_to_cpu(dp->dp_credit));
587 /* If the peer gave us the last packet it saw, process this as if
588 * we had received a regular ACK. */
590 rds_send_drop_acked(conn, be64_to_cpu(dp->dp_ack_seq), NULL);
592 BUG_ON(cm_id->context);
596 cm_id->context = conn;
598 /* We got halfway through setting up the ib_connection, if we
599 * fail now, we have to take the long route out of this mess. */
602 err = rds_ib_setup_qp(conn);
604 rds_ib_conn_error(conn, "rds_ib_setup_qp failed (%d)\n", err);
608 rds_ib_cm_fill_conn_param(conn, &conn_param, &dp_rep, version,
609 event->param.conn.responder_resources,
610 event->param.conn.initiator_depth);
612 /* rdma_accept() calls rdma_reject() internally if it fails */
613 err = rdma_accept(cm_id, &conn_param);
615 rds_ib_conn_error(conn, "rdma_accept failed (%d)\n", err);
619 mutex_unlock(&conn->c_cm_lock);
621 rdma_reject(cm_id, NULL, 0);
626 int rds_ib_cm_initiate_connect(struct rdma_cm_id *cm_id)
628 struct rds_connection *conn = cm_id->context;
629 struct rds_ib_connection *ic = conn->c_transport_data;
630 struct rdma_conn_param conn_param;
631 struct rds_ib_connect_private dp;
634 /* If the peer doesn't do protocol negotiation, we must
635 * default to RDSv3.0 */
636 rds_ib_set_protocol(conn, RDS_PROTOCOL_3_0);
637 ic->i_flowctl = rds_ib_sysctl_flow_control; /* advertise flow control */
639 ret = rds_ib_setup_qp(conn);
641 rds_ib_conn_error(conn, "rds_ib_setup_qp failed (%d)\n", ret);
645 rds_ib_cm_fill_conn_param(conn, &conn_param, &dp, RDS_PROTOCOL_VERSION,
647 ret = rdma_connect(cm_id, &conn_param);
649 rds_ib_conn_error(conn, "rdma_connect failed (%d)\n", ret);
652 /* Beware - returning non-zero tells the rdma_cm to destroy
653 * the cm_id. We should certainly not do it as long as we still
654 * "own" the cm_id. */
656 if (ic->i_cm_id == cm_id)
662 int rds_ib_conn_connect(struct rds_connection *conn)
664 struct rds_ib_connection *ic = conn->c_transport_data;
665 struct sockaddr_in src, dest;
668 /* XXX I wonder what affect the port space has */
669 /* delegate cm event handler to rdma_transport */
670 ic->i_cm_id = rdma_create_id(rds_rdma_cm_event_handler, conn,
671 RDMA_PS_TCP, IB_QPT_RC);
672 if (IS_ERR(ic->i_cm_id)) {
673 ret = PTR_ERR(ic->i_cm_id);
675 rdsdebug("rdma_create_id() failed: %d\n", ret);
679 rdsdebug("created cm id %p for conn %p\n", ic->i_cm_id, conn);
681 src.sin_family = AF_INET;
682 src.sin_addr.s_addr = (__force u32)conn->c_laddr;
683 src.sin_port = (__force u16)htons(0);
685 dest.sin_family = AF_INET;
686 dest.sin_addr.s_addr = (__force u32)conn->c_faddr;
687 dest.sin_port = (__force u16)htons(RDS_PORT);
689 ret = rdma_resolve_addr(ic->i_cm_id, (struct sockaddr *)&src,
690 (struct sockaddr *)&dest,
691 RDS_RDMA_RESOLVE_TIMEOUT_MS);
693 rdsdebug("addr resolve failed for cm id %p: %d\n", ic->i_cm_id,
695 rdma_destroy_id(ic->i_cm_id);
704 * This is so careful about only cleaning up resources that were built up
705 * so that it can be called at any point during startup. In fact it
706 * can be called multiple times for a given connection.
708 void rds_ib_conn_shutdown(struct rds_connection *conn)
710 struct rds_ib_connection *ic = conn->c_transport_data;
713 rdsdebug("cm %p pd %p cq %p %p qp %p\n", ic->i_cm_id,
714 ic->i_pd, ic->i_send_cq, ic->i_recv_cq,
715 ic->i_cm_id ? ic->i_cm_id->qp : NULL);
718 struct ib_device *dev = ic->i_cm_id->device;
720 rdsdebug("disconnecting cm %p\n", ic->i_cm_id);
721 err = rdma_disconnect(ic->i_cm_id);
723 /* Actually this may happen quite frequently, when
724 * an outgoing connect raced with an incoming connect.
726 rdsdebug("failed to disconnect, cm: %p err %d\n",
731 * We want to wait for tx and rx completion to finish
732 * before we tear down the connection, but we have to be
733 * careful not to get stuck waiting on a send ring that
734 * only has unsignaled sends in it. We've shutdown new
735 * sends before getting here so by waiting for signaled
736 * sends to complete we're ensured that there will be no
737 * more tx processing.
739 wait_event(rds_ib_ring_empty_wait,
740 rds_ib_ring_empty(&ic->i_recv_ring) &&
741 (atomic_read(&ic->i_signaled_sends) == 0));
742 tasklet_kill(&ic->i_send_tasklet);
743 tasklet_kill(&ic->i_recv_tasklet);
745 /* first destroy the ib state that generates callbacks */
747 rdma_destroy_qp(ic->i_cm_id);
749 ib_destroy_cq(ic->i_send_cq);
751 ib_destroy_cq(ic->i_recv_cq);
753 /* then free the resources that ib callbacks use */
755 ib_dma_free_coherent(dev,
756 ic->i_send_ring.w_nr *
757 sizeof(struct rds_header),
759 ic->i_send_hdrs_dma);
762 ib_dma_free_coherent(dev,
763 ic->i_recv_ring.w_nr *
764 sizeof(struct rds_header),
766 ic->i_recv_hdrs_dma);
769 ib_dma_free_coherent(dev, sizeof(struct rds_header),
770 ic->i_ack, ic->i_ack_dma);
773 rds_ib_send_clear_ring(ic);
775 rds_ib_recv_clear_ring(ic);
777 rdma_destroy_id(ic->i_cm_id);
780 * Move connection back to the nodev list.
783 rds_ib_remove_conn(ic->rds_ibdev, conn);
787 ic->i_send_cq = NULL;
788 ic->i_recv_cq = NULL;
789 ic->i_send_hdrs = NULL;
790 ic->i_recv_hdrs = NULL;
793 BUG_ON(ic->rds_ibdev);
795 /* Clear pending transmit */
797 struct rds_message *rm;
799 rm = container_of(ic->i_data_op, struct rds_message, data);
801 ic->i_data_op = NULL;
804 /* Clear the ACK state */
805 clear_bit(IB_ACK_IN_FLIGHT, &ic->i_ack_flags);
806 #ifdef KERNEL_HAS_ATOMIC64
807 atomic64_set(&ic->i_ack_next, 0);
813 /* Clear flow control state */
815 atomic_set(&ic->i_credits, 0);
817 rds_ib_ring_init(&ic->i_send_ring, rds_ib_sysctl_max_send_wr);
818 rds_ib_ring_init(&ic->i_recv_ring, rds_ib_sysctl_max_recv_wr);
821 rds_inc_put(&ic->i_ibinc->ii_inc);
831 int rds_ib_conn_alloc(struct rds_connection *conn, gfp_t gfp)
833 struct rds_ib_connection *ic;
838 ic = kzalloc(sizeof(struct rds_ib_connection), gfp);
842 ret = rds_ib_recv_alloc_caches(ic);
848 INIT_LIST_HEAD(&ic->ib_node);
849 tasklet_init(&ic->i_send_tasklet, rds_ib_tasklet_fn_send,
851 tasklet_init(&ic->i_recv_tasklet, rds_ib_tasklet_fn_recv,
853 mutex_init(&ic->i_recv_mutex);
854 #ifndef KERNEL_HAS_ATOMIC64
855 spin_lock_init(&ic->i_ack_lock);
857 atomic_set(&ic->i_signaled_sends, 0);
860 * rds_ib_conn_shutdown() waits for these to be emptied so they
861 * must be initialized before it can be called.
863 rds_ib_ring_init(&ic->i_send_ring, rds_ib_sysctl_max_send_wr);
864 rds_ib_ring_init(&ic->i_recv_ring, rds_ib_sysctl_max_recv_wr);
867 conn->c_transport_data = ic;
869 spin_lock_irqsave(&ib_nodev_conns_lock, flags);
870 list_add_tail(&ic->ib_node, &ib_nodev_conns);
871 spin_unlock_irqrestore(&ib_nodev_conns_lock, flags);
874 rdsdebug("conn %p conn ic %p\n", conn, conn->c_transport_data);
879 * Free a connection. Connection must be shut down and not set for reconnect.
881 void rds_ib_conn_free(void *arg)
883 struct rds_ib_connection *ic = arg;
884 spinlock_t *lock_ptr;
886 rdsdebug("ic %p\n", ic);
889 * Conn is either on a dev's list or on the nodev list.
890 * A race with shutdown() or connect() would cause problems
891 * (since rds_ibdev would change) but that should never happen.
893 lock_ptr = ic->rds_ibdev ? &ic->rds_ibdev->spinlock : &ib_nodev_conns_lock;
895 spin_lock_irq(lock_ptr);
896 list_del(&ic->ib_node);
897 spin_unlock_irq(lock_ptr);
899 rds_ib_recv_free_caches(ic);
906 * An error occurred on the connection
909 __rds_ib_conn_error(struct rds_connection *conn, const char *fmt, ...)