drm/amdgpu/vg20:Restruct uvd to support multiple uvds
[muen/linux.git] / net / rds / ib_cm.c
1 /*
2  * Copyright (c) 2006 Oracle.  All rights reserved.
3  *
4  * This software is available to you under a choice of one of two
5  * licenses.  You may choose to be licensed under the terms of the GNU
6  * General Public License (GPL) Version 2, available from the file
7  * COPYING in the main directory of this source tree, or the
8  * OpenIB.org BSD license below:
9  *
10  *     Redistribution and use in source and binary forms, with or
11  *     without modification, are permitted provided that the following
12  *     conditions are met:
13  *
14  *      - Redistributions of source code must retain the above
15  *        copyright notice, this list of conditions and the following
16  *        disclaimer.
17  *
18  *      - Redistributions in binary form must reproduce the above
19  *        copyright notice, this list of conditions and the following
20  *        disclaimer in the documentation and/or other materials
21  *        provided with the distribution.
22  *
23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30  * SOFTWARE.
31  *
32  */
33 #include <linux/kernel.h>
34 #include <linux/in.h>
35 #include <linux/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  */
46 static 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  */
54 static 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  */
81 static void
82 rds_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  */
96 void 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
175 static 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
217 static 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  */
231 static 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
243 static 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
266 static 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
287 static 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
306 static 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
338 static 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
360 static 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
372 static 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
389 static 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  */
398 static 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         return ret;
551
552 sends_out:
553         vfree(ic->i_sends);
554 ack_dma_out:
555         ib_dma_free_coherent(dev, sizeof(struct rds_header),
556                              ic->i_ack, ic->i_ack_dma);
557 recv_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);
561 send_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);
565 qp_out:
566         rdma_destroy_qp(ic->i_cm_id);
567 recv_cq_out:
568         if (!ib_destroy_cq(ic->i_recv_cq))
569                 ic->i_recv_cq = NULL;
570 send_cq_out:
571         if (!ib_destroy_cq(ic->i_send_cq))
572                 ic->i_send_cq = NULL;
573 rds_ibdev_out:
574         rds_ib_remove_conn(rds_ibdev, conn);
575         rds_ib_dev_put(rds_ibdev);
576
577         return ret;
578 }
579
580 static u32 rds_ib_protocol_compatible(struct rdma_cm_event *event)
581 {
582         const struct rds_ib_connect_private *dp = event->param.conn.private_data;
583         u16 common;
584         u32 version = 0;
585
586         /*
587          * rdma_cm private data is odd - when there is any private data in the
588          * request, we will be given a pretty large buffer without telling us the
589          * original size. The only way to tell the difference is by looking at
590          * the contents, which are initialized to zero.
591          * If the protocol version fields aren't set, this is a connection attempt
592          * from an older version. This could could be 3.0 or 2.0 - we can't tell.
593          * We really should have changed this for OFED 1.3 :-(
594          */
595
596         /* Be paranoid. RDS always has privdata */
597         if (!event->param.conn.private_data_len) {
598                 printk(KERN_NOTICE "RDS incoming connection has no private data, "
599                         "rejecting\n");
600                 return 0;
601         }
602
603         /* Even if len is crap *now* I still want to check it. -ASG */
604         if (event->param.conn.private_data_len < sizeof (*dp) ||
605             dp->dp_protocol_major == 0)
606                 return RDS_PROTOCOL_3_0;
607
608         common = be16_to_cpu(dp->dp_protocol_minor_mask) & RDS_IB_SUPPORTED_PROTOCOLS;
609         if (dp->dp_protocol_major == 3 && common) {
610                 version = RDS_PROTOCOL_3_0;
611                 while ((common >>= 1) != 0)
612                         version++;
613         } else
614                 printk_ratelimited(KERN_NOTICE "RDS: Connection from %pI4 using incompatible protocol version %u.%u\n",
615                                 &dp->dp_saddr,
616                                 dp->dp_protocol_major,
617                                 dp->dp_protocol_minor);
618         return version;
619 }
620
621 int rds_ib_cm_handle_connect(struct rdma_cm_id *cm_id,
622                                     struct rdma_cm_event *event)
623 {
624         __be64 lguid = cm_id->route.path_rec->sgid.global.interface_id;
625         __be64 fguid = cm_id->route.path_rec->dgid.global.interface_id;
626         const struct rds_ib_connect_private *dp = event->param.conn.private_data;
627         struct rds_ib_connect_private dp_rep;
628         struct rds_connection *conn = NULL;
629         struct rds_ib_connection *ic = NULL;
630         struct rdma_conn_param conn_param;
631         u32 version;
632         int err = 1, destroy = 1;
633
634         /* Check whether the remote protocol version matches ours. */
635         version = rds_ib_protocol_compatible(event);
636         if (!version)
637                 goto out;
638
639         rdsdebug("saddr %pI4 daddr %pI4 RDSv%u.%u lguid 0x%llx fguid "
640                  "0x%llx\n", &dp->dp_saddr, &dp->dp_daddr,
641                  RDS_PROTOCOL_MAJOR(version), RDS_PROTOCOL_MINOR(version),
642                  (unsigned long long)be64_to_cpu(lguid),
643                  (unsigned long long)be64_to_cpu(fguid));
644
645         /* RDS/IB is not currently netns aware, thus init_net */
646         conn = rds_conn_create(&init_net, dp->dp_daddr, dp->dp_saddr,
647                                &rds_ib_transport, GFP_KERNEL);
648         if (IS_ERR(conn)) {
649                 rdsdebug("rds_conn_create failed (%ld)\n", PTR_ERR(conn));
650                 conn = NULL;
651                 goto out;
652         }
653
654         /*
655          * The connection request may occur while the
656          * previous connection exist, e.g. in case of failover.
657          * But as connections may be initiated simultaneously
658          * by both hosts, we have a random backoff mechanism -
659          * see the comment above rds_queue_reconnect()
660          */
661         mutex_lock(&conn->c_cm_lock);
662         if (!rds_conn_transition(conn, RDS_CONN_DOWN, RDS_CONN_CONNECTING)) {
663                 if (rds_conn_state(conn) == RDS_CONN_UP) {
664                         rdsdebug("incoming connect while connecting\n");
665                         rds_conn_drop(conn);
666                         rds_ib_stats_inc(s_ib_listen_closed_stale);
667                 } else
668                 if (rds_conn_state(conn) == RDS_CONN_CONNECTING) {
669                         /* Wait and see - our connect may still be succeeding */
670                         rds_ib_stats_inc(s_ib_connect_raced);
671                 }
672                 goto out;
673         }
674
675         ic = conn->c_transport_data;
676
677         rds_ib_set_protocol(conn, version);
678         rds_ib_set_flow_control(conn, be32_to_cpu(dp->dp_credit));
679
680         /* If the peer gave us the last packet it saw, process this as if
681          * we had received a regular ACK. */
682         if (dp->dp_ack_seq)
683                 rds_send_drop_acked(conn, be64_to_cpu(dp->dp_ack_seq), NULL);
684
685         BUG_ON(cm_id->context);
686         BUG_ON(ic->i_cm_id);
687
688         ic->i_cm_id = cm_id;
689         cm_id->context = conn;
690
691         /* We got halfway through setting up the ib_connection, if we
692          * fail now, we have to take the long route out of this mess. */
693         destroy = 0;
694
695         err = rds_ib_setup_qp(conn);
696         if (err) {
697                 rds_ib_conn_error(conn, "rds_ib_setup_qp failed (%d)\n", err);
698                 goto out;
699         }
700
701         rds_ib_cm_fill_conn_param(conn, &conn_param, &dp_rep, version,
702                 event->param.conn.responder_resources,
703                 event->param.conn.initiator_depth);
704
705         /* rdma_accept() calls rdma_reject() internally if it fails */
706         if (rdma_accept(cm_id, &conn_param))
707                 rds_ib_conn_error(conn, "rdma_accept failed\n");
708
709 out:
710         if (conn)
711                 mutex_unlock(&conn->c_cm_lock);
712         if (err)
713                 rdma_reject(cm_id, NULL, 0);
714         return destroy;
715 }
716
717
718 int rds_ib_cm_initiate_connect(struct rdma_cm_id *cm_id)
719 {
720         struct rds_connection *conn = cm_id->context;
721         struct rds_ib_connection *ic = conn->c_transport_data;
722         struct rdma_conn_param conn_param;
723         struct rds_ib_connect_private dp;
724         int ret;
725
726         /* If the peer doesn't do protocol negotiation, we must
727          * default to RDSv3.0 */
728         rds_ib_set_protocol(conn, RDS_PROTOCOL_3_0);
729         ic->i_flowctl = rds_ib_sysctl_flow_control;     /* advertise flow control */
730
731         ret = rds_ib_setup_qp(conn);
732         if (ret) {
733                 rds_ib_conn_error(conn, "rds_ib_setup_qp failed (%d)\n", ret);
734                 goto out;
735         }
736
737         rds_ib_cm_fill_conn_param(conn, &conn_param, &dp, RDS_PROTOCOL_VERSION,
738                 UINT_MAX, UINT_MAX);
739         ret = rdma_connect(cm_id, &conn_param);
740         if (ret)
741                 rds_ib_conn_error(conn, "rdma_connect failed (%d)\n", ret);
742
743 out:
744         /* Beware - returning non-zero tells the rdma_cm to destroy
745          * the cm_id. We should certainly not do it as long as we still
746          * "own" the cm_id. */
747         if (ret) {
748                 if (ic->i_cm_id == cm_id)
749                         ret = 0;
750         }
751         ic->i_active_side = true;
752         return ret;
753 }
754
755 int rds_ib_conn_path_connect(struct rds_conn_path *cp)
756 {
757         struct rds_connection *conn = cp->cp_conn;
758         struct rds_ib_connection *ic = conn->c_transport_data;
759         struct sockaddr_in src, dest;
760         int ret;
761
762         /* XXX I wonder what affect the port space has */
763         /* delegate cm event handler to rdma_transport */
764         ic->i_cm_id = rdma_create_id(&init_net, rds_rdma_cm_event_handler, conn,
765                                      RDMA_PS_TCP, IB_QPT_RC);
766         if (IS_ERR(ic->i_cm_id)) {
767                 ret = PTR_ERR(ic->i_cm_id);
768                 ic->i_cm_id = NULL;
769                 rdsdebug("rdma_create_id() failed: %d\n", ret);
770                 goto out;
771         }
772
773         rdsdebug("created cm id %p for conn %p\n", ic->i_cm_id, conn);
774
775         src.sin_family = AF_INET;
776         src.sin_addr.s_addr = (__force u32)conn->c_laddr;
777         src.sin_port = (__force u16)htons(0);
778
779         dest.sin_family = AF_INET;
780         dest.sin_addr.s_addr = (__force u32)conn->c_faddr;
781         dest.sin_port = (__force u16)htons(RDS_PORT);
782
783         ret = rdma_resolve_addr(ic->i_cm_id, (struct sockaddr *)&src,
784                                 (struct sockaddr *)&dest,
785                                 RDS_RDMA_RESOLVE_TIMEOUT_MS);
786         if (ret) {
787                 rdsdebug("addr resolve failed for cm id %p: %d\n", ic->i_cm_id,
788                          ret);
789                 rdma_destroy_id(ic->i_cm_id);
790                 ic->i_cm_id = NULL;
791         }
792
793 out:
794         return ret;
795 }
796
797 /*
798  * This is so careful about only cleaning up resources that were built up
799  * so that it can be called at any point during startup.  In fact it
800  * can be called multiple times for a given connection.
801  */
802 void rds_ib_conn_path_shutdown(struct rds_conn_path *cp)
803 {
804         struct rds_connection *conn = cp->cp_conn;
805         struct rds_ib_connection *ic = conn->c_transport_data;
806         int err = 0;
807
808         rdsdebug("cm %p pd %p cq %p %p qp %p\n", ic->i_cm_id,
809                  ic->i_pd, ic->i_send_cq, ic->i_recv_cq,
810                  ic->i_cm_id ? ic->i_cm_id->qp : NULL);
811
812         if (ic->i_cm_id) {
813                 struct ib_device *dev = ic->i_cm_id->device;
814
815                 rdsdebug("disconnecting cm %p\n", ic->i_cm_id);
816                 err = rdma_disconnect(ic->i_cm_id);
817                 if (err) {
818                         /* Actually this may happen quite frequently, when
819                          * an outgoing connect raced with an incoming connect.
820                          */
821                         rdsdebug("failed to disconnect, cm: %p err %d\n",
822                                 ic->i_cm_id, err);
823                 }
824
825                 /*
826                  * We want to wait for tx and rx completion to finish
827                  * before we tear down the connection, but we have to be
828                  * careful not to get stuck waiting on a send ring that
829                  * only has unsignaled sends in it.  We've shutdown new
830                  * sends before getting here so by waiting for signaled
831                  * sends to complete we're ensured that there will be no
832                  * more tx processing.
833                  */
834                 wait_event(rds_ib_ring_empty_wait,
835                            rds_ib_ring_empty(&ic->i_recv_ring) &&
836                            (atomic_read(&ic->i_signaled_sends) == 0) &&
837                            (atomic_read(&ic->i_fastreg_wrs) == RDS_IB_DEFAULT_FR_WR) &&
838                            (atomic_read(&ic->i_fastunreg_wrs) == RDS_IB_DEFAULT_FR_INV_WR));
839                 tasklet_kill(&ic->i_send_tasklet);
840                 tasklet_kill(&ic->i_recv_tasklet);
841
842                 atomic_set(&ic->i_cq_quiesce, 1);
843
844                 /* first destroy the ib state that generates callbacks */
845                 if (ic->i_cm_id->qp)
846                         rdma_destroy_qp(ic->i_cm_id);
847                 if (ic->i_send_cq) {
848                         if (ic->rds_ibdev)
849                                 ibdev_put_vector(ic->rds_ibdev, ic->i_scq_vector);
850                         ib_destroy_cq(ic->i_send_cq);
851                 }
852
853                 if (ic->i_recv_cq) {
854                         if (ic->rds_ibdev)
855                                 ibdev_put_vector(ic->rds_ibdev, ic->i_rcq_vector);
856                         ib_destroy_cq(ic->i_recv_cq);
857                 }
858
859                 /* then free the resources that ib callbacks use */
860                 if (ic->i_send_hdrs)
861                         ib_dma_free_coherent(dev,
862                                            ic->i_send_ring.w_nr *
863                                                 sizeof(struct rds_header),
864                                            ic->i_send_hdrs,
865                                            ic->i_send_hdrs_dma);
866
867                 if (ic->i_recv_hdrs)
868                         ib_dma_free_coherent(dev,
869                                            ic->i_recv_ring.w_nr *
870                                                 sizeof(struct rds_header),
871                                            ic->i_recv_hdrs,
872                                            ic->i_recv_hdrs_dma);
873
874                 if (ic->i_ack)
875                         ib_dma_free_coherent(dev, sizeof(struct rds_header),
876                                              ic->i_ack, ic->i_ack_dma);
877
878                 if (ic->i_sends)
879                         rds_ib_send_clear_ring(ic);
880                 if (ic->i_recvs)
881                         rds_ib_recv_clear_ring(ic);
882
883                 rdma_destroy_id(ic->i_cm_id);
884
885                 /*
886                  * Move connection back to the nodev list.
887                  */
888                 if (ic->rds_ibdev)
889                         rds_ib_remove_conn(ic->rds_ibdev, conn);
890
891                 ic->i_cm_id = NULL;
892                 ic->i_pd = NULL;
893                 ic->i_send_cq = NULL;
894                 ic->i_recv_cq = NULL;
895                 ic->i_send_hdrs = NULL;
896                 ic->i_recv_hdrs = NULL;
897                 ic->i_ack = NULL;
898         }
899         BUG_ON(ic->rds_ibdev);
900
901         /* Clear pending transmit */
902         if (ic->i_data_op) {
903                 struct rds_message *rm;
904
905                 rm = container_of(ic->i_data_op, struct rds_message, data);
906                 rds_message_put(rm);
907                 ic->i_data_op = NULL;
908         }
909
910         /* Clear the ACK state */
911         clear_bit(IB_ACK_IN_FLIGHT, &ic->i_ack_flags);
912 #ifdef KERNEL_HAS_ATOMIC64
913         atomic64_set(&ic->i_ack_next, 0);
914 #else
915         ic->i_ack_next = 0;
916 #endif
917         ic->i_ack_recv = 0;
918
919         /* Clear flow control state */
920         ic->i_flowctl = 0;
921         atomic_set(&ic->i_credits, 0);
922
923         rds_ib_ring_init(&ic->i_send_ring, rds_ib_sysctl_max_send_wr);
924         rds_ib_ring_init(&ic->i_recv_ring, rds_ib_sysctl_max_recv_wr);
925
926         if (ic->i_ibinc) {
927                 rds_inc_put(&ic->i_ibinc->ii_inc);
928                 ic->i_ibinc = NULL;
929         }
930
931         vfree(ic->i_sends);
932         ic->i_sends = NULL;
933         vfree(ic->i_recvs);
934         ic->i_recvs = NULL;
935         ic->i_active_side = false;
936 }
937
938 int rds_ib_conn_alloc(struct rds_connection *conn, gfp_t gfp)
939 {
940         struct rds_ib_connection *ic;
941         unsigned long flags;
942         int ret;
943
944         /* XXX too lazy? */
945         ic = kzalloc(sizeof(struct rds_ib_connection), gfp);
946         if (!ic)
947                 return -ENOMEM;
948
949         ret = rds_ib_recv_alloc_caches(ic);
950         if (ret) {
951                 kfree(ic);
952                 return ret;
953         }
954
955         INIT_LIST_HEAD(&ic->ib_node);
956         tasklet_init(&ic->i_send_tasklet, rds_ib_tasklet_fn_send,
957                      (unsigned long)ic);
958         tasklet_init(&ic->i_recv_tasklet, rds_ib_tasklet_fn_recv,
959                      (unsigned long)ic);
960         mutex_init(&ic->i_recv_mutex);
961 #ifndef KERNEL_HAS_ATOMIC64
962         spin_lock_init(&ic->i_ack_lock);
963 #endif
964         atomic_set(&ic->i_signaled_sends, 0);
965
966         /*
967          * rds_ib_conn_shutdown() waits for these to be emptied so they
968          * must be initialized before it can be called.
969          */
970         rds_ib_ring_init(&ic->i_send_ring, rds_ib_sysctl_max_send_wr);
971         rds_ib_ring_init(&ic->i_recv_ring, rds_ib_sysctl_max_recv_wr);
972
973         ic->conn = conn;
974         conn->c_transport_data = ic;
975
976         spin_lock_irqsave(&ib_nodev_conns_lock, flags);
977         list_add_tail(&ic->ib_node, &ib_nodev_conns);
978         spin_unlock_irqrestore(&ib_nodev_conns_lock, flags);
979
980
981         rdsdebug("conn %p conn ic %p\n", conn, conn->c_transport_data);
982         return 0;
983 }
984
985 /*
986  * Free a connection. Connection must be shut down and not set for reconnect.
987  */
988 void rds_ib_conn_free(void *arg)
989 {
990         struct rds_ib_connection *ic = arg;
991         spinlock_t      *lock_ptr;
992
993         rdsdebug("ic %p\n", ic);
994
995         /*
996          * Conn is either on a dev's list or on the nodev list.
997          * A race with shutdown() or connect() would cause problems
998          * (since rds_ibdev would change) but that should never happen.
999          */
1000         lock_ptr = ic->rds_ibdev ? &ic->rds_ibdev->spinlock : &ib_nodev_conns_lock;
1001
1002         spin_lock_irq(lock_ptr);
1003         list_del(&ic->ib_node);
1004         spin_unlock_irq(lock_ptr);
1005
1006         rds_ib_recv_free_caches(ic);
1007
1008         kfree(ic);
1009 }
1010
1011
1012 /*
1013  * An error occurred on the connection
1014  */
1015 void
1016 __rds_ib_conn_error(struct rds_connection *conn, const char *fmt, ...)
1017 {
1018         va_list ap;
1019
1020         rds_conn_drop(conn);
1021
1022         va_start(ap, fmt);
1023         vprintk(fmt, ap);
1024         va_end(ap);
1025 }