Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6
[linux-2.6] / drivers / infiniband / ulp / ipoib / ipoib_cm.c
1 /*
2  * Copyright (c) 2006 Mellanox Technologies. 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 <rdma/ib_cm.h>
34 #include <rdma/ib_cache.h>
35 #include <net/dst.h>
36 #include <net/icmp.h>
37 #include <linux/icmpv6.h>
38 #include <linux/delay.h>
39 #include <linux/vmalloc.h>
40
41 #include "ipoib.h"
42
43 int ipoib_max_conn_qp = 128;
44
45 module_param_named(max_nonsrq_conn_qp, ipoib_max_conn_qp, int, 0444);
46 MODULE_PARM_DESC(max_nonsrq_conn_qp,
47                  "Max number of connected-mode QPs per interface "
48                  "(applied only if shared receive queue is not available)");
49
50 #ifdef CONFIG_INFINIBAND_IPOIB_DEBUG_DATA
51 static int data_debug_level;
52
53 module_param_named(cm_data_debug_level, data_debug_level, int, 0644);
54 MODULE_PARM_DESC(cm_data_debug_level,
55                  "Enable data path debug tracing for connected mode if > 0");
56 #endif
57
58 #define IPOIB_CM_IETF_ID 0x1000000000000000ULL
59
60 #define IPOIB_CM_RX_UPDATE_TIME (256 * HZ)
61 #define IPOIB_CM_RX_TIMEOUT     (2 * 256 * HZ)
62 #define IPOIB_CM_RX_DELAY       (3 * 256 * HZ)
63 #define IPOIB_CM_RX_UPDATE_MASK (0x3)
64
65 static struct ib_qp_attr ipoib_cm_err_attr = {
66         .qp_state = IB_QPS_ERR
67 };
68
69 #define IPOIB_CM_RX_DRAIN_WRID 0xffffffff
70
71 static struct ib_send_wr ipoib_cm_rx_drain_wr = {
72         .wr_id = IPOIB_CM_RX_DRAIN_WRID,
73         .opcode = IB_WR_SEND,
74 };
75
76 static int ipoib_cm_tx_handler(struct ib_cm_id *cm_id,
77                                struct ib_cm_event *event);
78
79 static void ipoib_cm_dma_unmap_rx(struct ipoib_dev_priv *priv, int frags,
80                                   u64 mapping[IPOIB_CM_RX_SG])
81 {
82         int i;
83
84         ib_dma_unmap_single(priv->ca, mapping[0], IPOIB_CM_HEAD_SIZE, DMA_FROM_DEVICE);
85
86         for (i = 0; i < frags; ++i)
87                 ib_dma_unmap_single(priv->ca, mapping[i + 1], PAGE_SIZE, DMA_FROM_DEVICE);
88 }
89
90 static int ipoib_cm_post_receive_srq(struct net_device *dev, int id)
91 {
92         struct ipoib_dev_priv *priv = netdev_priv(dev);
93         struct ib_recv_wr *bad_wr;
94         int i, ret;
95
96         priv->cm.rx_wr.wr_id = id | IPOIB_OP_CM | IPOIB_OP_RECV;
97
98         for (i = 0; i < priv->cm.num_frags; ++i)
99                 priv->cm.rx_sge[i].addr = priv->cm.srq_ring[id].mapping[i];
100
101         ret = ib_post_srq_recv(priv->cm.srq, &priv->cm.rx_wr, &bad_wr);
102         if (unlikely(ret)) {
103                 ipoib_warn(priv, "post srq failed for buf %d (%d)\n", id, ret);
104                 ipoib_cm_dma_unmap_rx(priv, priv->cm.num_frags - 1,
105                                       priv->cm.srq_ring[id].mapping);
106                 dev_kfree_skb_any(priv->cm.srq_ring[id].skb);
107                 priv->cm.srq_ring[id].skb = NULL;
108         }
109
110         return ret;
111 }
112
113 static int ipoib_cm_post_receive_nonsrq(struct net_device *dev,
114                                         struct ipoib_cm_rx *rx,
115                                         struct ib_recv_wr *wr,
116                                         struct ib_sge *sge, int id)
117 {
118         struct ipoib_dev_priv *priv = netdev_priv(dev);
119         struct ib_recv_wr *bad_wr;
120         int i, ret;
121
122         wr->wr_id = id | IPOIB_OP_CM | IPOIB_OP_RECV;
123
124         for (i = 0; i < IPOIB_CM_RX_SG; ++i)
125                 sge[i].addr = rx->rx_ring[id].mapping[i];
126
127         ret = ib_post_recv(rx->qp, wr, &bad_wr);
128         if (unlikely(ret)) {
129                 ipoib_warn(priv, "post recv failed for buf %d (%d)\n", id, ret);
130                 ipoib_cm_dma_unmap_rx(priv, IPOIB_CM_RX_SG - 1,
131                                       rx->rx_ring[id].mapping);
132                 dev_kfree_skb_any(rx->rx_ring[id].skb);
133                 rx->rx_ring[id].skb = NULL;
134         }
135
136         return ret;
137 }
138
139 static struct sk_buff *ipoib_cm_alloc_rx_skb(struct net_device *dev,
140                                              struct ipoib_cm_rx_buf *rx_ring,
141                                              int id, int frags,
142                                              u64 mapping[IPOIB_CM_RX_SG])
143 {
144         struct ipoib_dev_priv *priv = netdev_priv(dev);
145         struct sk_buff *skb;
146         int i;
147
148         skb = dev_alloc_skb(IPOIB_CM_HEAD_SIZE + 12);
149         if (unlikely(!skb))
150                 return NULL;
151
152         /*
153          * IPoIB adds a 4 byte header. So we need 12 more bytes to align the
154          * IP header to a multiple of 16.
155          */
156         skb_reserve(skb, 12);
157
158         mapping[0] = ib_dma_map_single(priv->ca, skb->data, IPOIB_CM_HEAD_SIZE,
159                                        DMA_FROM_DEVICE);
160         if (unlikely(ib_dma_mapping_error(priv->ca, mapping[0]))) {
161                 dev_kfree_skb_any(skb);
162                 return NULL;
163         }
164
165         for (i = 0; i < frags; i++) {
166                 struct page *page = alloc_page(GFP_ATOMIC);
167
168                 if (!page)
169                         goto partial_error;
170                 skb_fill_page_desc(skb, i, page, 0, PAGE_SIZE);
171
172                 mapping[i + 1] = ib_dma_map_page(priv->ca, skb_shinfo(skb)->frags[i].page,
173                                                  0, PAGE_SIZE, DMA_FROM_DEVICE);
174                 if (unlikely(ib_dma_mapping_error(priv->ca, mapping[i + 1])))
175                         goto partial_error;
176         }
177
178         rx_ring[id].skb = skb;
179         return skb;
180
181 partial_error:
182
183         ib_dma_unmap_single(priv->ca, mapping[0], IPOIB_CM_HEAD_SIZE, DMA_FROM_DEVICE);
184
185         for (; i > 0; --i)
186                 ib_dma_unmap_single(priv->ca, mapping[i], PAGE_SIZE, DMA_FROM_DEVICE);
187
188         dev_kfree_skb_any(skb);
189         return NULL;
190 }
191
192 static void ipoib_cm_free_rx_ring(struct net_device *dev,
193                                   struct ipoib_cm_rx_buf *rx_ring)
194 {
195         struct ipoib_dev_priv *priv = netdev_priv(dev);
196         int i;
197
198         for (i = 0; i < ipoib_recvq_size; ++i)
199                 if (rx_ring[i].skb) {
200                         ipoib_cm_dma_unmap_rx(priv, IPOIB_CM_RX_SG - 1,
201                                               rx_ring[i].mapping);
202                         dev_kfree_skb_any(rx_ring[i].skb);
203                 }
204
205         vfree(rx_ring);
206 }
207
208 static void ipoib_cm_start_rx_drain(struct ipoib_dev_priv *priv)
209 {
210         struct ib_send_wr *bad_wr;
211         struct ipoib_cm_rx *p;
212
213         /* We only reserved 1 extra slot in CQ for drain WRs, so
214          * make sure we have at most 1 outstanding WR. */
215         if (list_empty(&priv->cm.rx_flush_list) ||
216             !list_empty(&priv->cm.rx_drain_list))
217                 return;
218
219         /*
220          * QPs on flush list are error state.  This way, a "flush
221          * error" WC will be immediately generated for each WR we post.
222          */
223         p = list_entry(priv->cm.rx_flush_list.next, typeof(*p), list);
224         if (ib_post_send(p->qp, &ipoib_cm_rx_drain_wr, &bad_wr))
225                 ipoib_warn(priv, "failed to post drain wr\n");
226
227         list_splice_init(&priv->cm.rx_flush_list, &priv->cm.rx_drain_list);
228 }
229
230 static void ipoib_cm_rx_event_handler(struct ib_event *event, void *ctx)
231 {
232         struct ipoib_cm_rx *p = ctx;
233         struct ipoib_dev_priv *priv = netdev_priv(p->dev);
234         unsigned long flags;
235
236         if (event->event != IB_EVENT_QP_LAST_WQE_REACHED)
237                 return;
238
239         spin_lock_irqsave(&priv->lock, flags);
240         list_move(&p->list, &priv->cm.rx_flush_list);
241         p->state = IPOIB_CM_RX_FLUSH;
242         ipoib_cm_start_rx_drain(priv);
243         spin_unlock_irqrestore(&priv->lock, flags);
244 }
245
246 static struct ib_qp *ipoib_cm_create_rx_qp(struct net_device *dev,
247                                            struct ipoib_cm_rx *p)
248 {
249         struct ipoib_dev_priv *priv = netdev_priv(dev);
250         struct ib_qp_init_attr attr = {
251                 .event_handler = ipoib_cm_rx_event_handler,
252                 .send_cq = priv->recv_cq, /* For drain WR */
253                 .recv_cq = priv->recv_cq,
254                 .srq = priv->cm.srq,
255                 .cap.max_send_wr = 1, /* For drain WR */
256                 .cap.max_send_sge = 1, /* FIXME: 0 Seems not to work */
257                 .sq_sig_type = IB_SIGNAL_ALL_WR,
258                 .qp_type = IB_QPT_RC,
259                 .qp_context = p,
260         };
261
262         if (!ipoib_cm_has_srq(dev)) {
263                 attr.cap.max_recv_wr  = ipoib_recvq_size;
264                 attr.cap.max_recv_sge = IPOIB_CM_RX_SG;
265         }
266
267         return ib_create_qp(priv->pd, &attr);
268 }
269
270 static int ipoib_cm_modify_rx_qp(struct net_device *dev,
271                                  struct ib_cm_id *cm_id, struct ib_qp *qp,
272                                  unsigned psn)
273 {
274         struct ipoib_dev_priv *priv = netdev_priv(dev);
275         struct ib_qp_attr qp_attr;
276         int qp_attr_mask, ret;
277
278         qp_attr.qp_state = IB_QPS_INIT;
279         ret = ib_cm_init_qp_attr(cm_id, &qp_attr, &qp_attr_mask);
280         if (ret) {
281                 ipoib_warn(priv, "failed to init QP attr for INIT: %d\n", ret);
282                 return ret;
283         }
284         ret = ib_modify_qp(qp, &qp_attr, qp_attr_mask);
285         if (ret) {
286                 ipoib_warn(priv, "failed to modify QP to INIT: %d\n", ret);
287                 return ret;
288         }
289         qp_attr.qp_state = IB_QPS_RTR;
290         ret = ib_cm_init_qp_attr(cm_id, &qp_attr, &qp_attr_mask);
291         if (ret) {
292                 ipoib_warn(priv, "failed to init QP attr for RTR: %d\n", ret);
293                 return ret;
294         }
295         qp_attr.rq_psn = psn;
296         ret = ib_modify_qp(qp, &qp_attr, qp_attr_mask);
297         if (ret) {
298                 ipoib_warn(priv, "failed to modify QP to RTR: %d\n", ret);
299                 return ret;
300         }
301
302         /*
303          * Current Mellanox HCA firmware won't generate completions
304          * with error for drain WRs unless the QP has been moved to
305          * RTS first. This work-around leaves a window where a QP has
306          * moved to error asynchronously, but this will eventually get
307          * fixed in firmware, so let's not error out if modify QP
308          * fails.
309          */
310         qp_attr.qp_state = IB_QPS_RTS;
311         ret = ib_cm_init_qp_attr(cm_id, &qp_attr, &qp_attr_mask);
312         if (ret) {
313                 ipoib_warn(priv, "failed to init QP attr for RTS: %d\n", ret);
314                 return 0;
315         }
316         ret = ib_modify_qp(qp, &qp_attr, qp_attr_mask);
317         if (ret) {
318                 ipoib_warn(priv, "failed to modify QP to RTS: %d\n", ret);
319                 return 0;
320         }
321
322         return 0;
323 }
324
325 static void ipoib_cm_init_rx_wr(struct net_device *dev,
326                                 struct ib_recv_wr *wr,
327                                 struct ib_sge *sge)
328 {
329         struct ipoib_dev_priv *priv = netdev_priv(dev);
330         int i;
331
332         for (i = 0; i < priv->cm.num_frags; ++i)
333                 sge[i].lkey = priv->mr->lkey;
334
335         sge[0].length = IPOIB_CM_HEAD_SIZE;
336         for (i = 1; i < priv->cm.num_frags; ++i)
337                 sge[i].length = PAGE_SIZE;
338
339         wr->next    = NULL;
340         wr->sg_list = sge;
341         wr->num_sge = priv->cm.num_frags;
342 }
343
344 static int ipoib_cm_nonsrq_init_rx(struct net_device *dev, struct ib_cm_id *cm_id,
345                                    struct ipoib_cm_rx *rx)
346 {
347         struct ipoib_dev_priv *priv = netdev_priv(dev);
348         struct {
349                 struct ib_recv_wr wr;
350                 struct ib_sge sge[IPOIB_CM_RX_SG];
351         } *t;
352         int ret;
353         int i;
354
355         rx->rx_ring = vmalloc(ipoib_recvq_size * sizeof *rx->rx_ring);
356         if (!rx->rx_ring) {
357                 printk(KERN_WARNING "%s: failed to allocate CM non-SRQ ring (%d entries)\n",
358                        priv->ca->name, ipoib_recvq_size);
359                 return -ENOMEM;
360         }
361
362         memset(rx->rx_ring, 0, ipoib_recvq_size * sizeof *rx->rx_ring);
363
364         t = kmalloc(sizeof *t, GFP_KERNEL);
365         if (!t) {
366                 ret = -ENOMEM;
367                 goto err_free;
368         }
369
370         ipoib_cm_init_rx_wr(dev, &t->wr, t->sge);
371
372         spin_lock_irq(&priv->lock);
373
374         if (priv->cm.nonsrq_conn_qp >= ipoib_max_conn_qp) {
375                 spin_unlock_irq(&priv->lock);
376                 ib_send_cm_rej(cm_id, IB_CM_REJ_NO_QP, NULL, 0, NULL, 0);
377                 ret = -EINVAL;
378                 goto err_free;
379         } else
380                 ++priv->cm.nonsrq_conn_qp;
381
382         spin_unlock_irq(&priv->lock);
383
384         for (i = 0; i < ipoib_recvq_size; ++i) {
385                 if (!ipoib_cm_alloc_rx_skb(dev, rx->rx_ring, i, IPOIB_CM_RX_SG - 1,
386                                            rx->rx_ring[i].mapping)) {
387                         ipoib_warn(priv, "failed to allocate receive buffer %d\n", i);
388                                 ret = -ENOMEM;
389                                 goto err_count;
390                 }
391                 ret = ipoib_cm_post_receive_nonsrq(dev, rx, &t->wr, t->sge, i);
392                 if (ret) {
393                         ipoib_warn(priv, "ipoib_cm_post_receive_nonsrq "
394                                    "failed for buf %d\n", i);
395                         ret = -EIO;
396                         goto err_count;
397                 }
398         }
399
400         rx->recv_count = ipoib_recvq_size;
401
402         kfree(t);
403
404         return 0;
405
406 err_count:
407         spin_lock_irq(&priv->lock);
408         --priv->cm.nonsrq_conn_qp;
409         spin_unlock_irq(&priv->lock);
410
411 err_free:
412         kfree(t);
413         ipoib_cm_free_rx_ring(dev, rx->rx_ring);
414
415         return ret;
416 }
417
418 static int ipoib_cm_send_rep(struct net_device *dev, struct ib_cm_id *cm_id,
419                              struct ib_qp *qp, struct ib_cm_req_event_param *req,
420                              unsigned psn)
421 {
422         struct ipoib_dev_priv *priv = netdev_priv(dev);
423         struct ipoib_cm_data data = {};
424         struct ib_cm_rep_param rep = {};
425
426         data.qpn = cpu_to_be32(priv->qp->qp_num);
427         data.mtu = cpu_to_be32(IPOIB_CM_BUF_SIZE);
428
429         rep.private_data = &data;
430         rep.private_data_len = sizeof data;
431         rep.flow_control = 0;
432         rep.rnr_retry_count = req->rnr_retry_count;
433         rep.srq = ipoib_cm_has_srq(dev);
434         rep.qp_num = qp->qp_num;
435         rep.starting_psn = psn;
436         return ib_send_cm_rep(cm_id, &rep);
437 }
438
439 static int ipoib_cm_req_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event)
440 {
441         struct net_device *dev = cm_id->context;
442         struct ipoib_dev_priv *priv = netdev_priv(dev);
443         struct ipoib_cm_rx *p;
444         unsigned psn;
445         int ret;
446
447         ipoib_dbg(priv, "REQ arrived\n");
448         p = kzalloc(sizeof *p, GFP_KERNEL);
449         if (!p)
450                 return -ENOMEM;
451         p->dev = dev;
452         p->id = cm_id;
453         cm_id->context = p;
454         p->state = IPOIB_CM_RX_LIVE;
455         p->jiffies = jiffies;
456         INIT_LIST_HEAD(&p->list);
457
458         p->qp = ipoib_cm_create_rx_qp(dev, p);
459         if (IS_ERR(p->qp)) {
460                 ret = PTR_ERR(p->qp);
461                 goto err_qp;
462         }
463
464         psn = random32() & 0xffffff;
465         ret = ipoib_cm_modify_rx_qp(dev, cm_id, p->qp, psn);
466         if (ret)
467                 goto err_modify;
468
469         if (!ipoib_cm_has_srq(dev)) {
470                 ret = ipoib_cm_nonsrq_init_rx(dev, cm_id, p);
471                 if (ret)
472                         goto err_modify;
473         }
474
475         spin_lock_irq(&priv->lock);
476         queue_delayed_work(ipoib_workqueue,
477                            &priv->cm.stale_task, IPOIB_CM_RX_DELAY);
478         /* Add this entry to passive ids list head, but do not re-add it
479          * if IB_EVENT_QP_LAST_WQE_REACHED has moved it to flush list. */
480         p->jiffies = jiffies;
481         if (p->state == IPOIB_CM_RX_LIVE)
482                 list_move(&p->list, &priv->cm.passive_ids);
483         spin_unlock_irq(&priv->lock);
484
485         ret = ipoib_cm_send_rep(dev, cm_id, p->qp, &event->param.req_rcvd, psn);
486         if (ret) {
487                 ipoib_warn(priv, "failed to send REP: %d\n", ret);
488                 if (ib_modify_qp(p->qp, &ipoib_cm_err_attr, IB_QP_STATE))
489                         ipoib_warn(priv, "unable to move qp to error state\n");
490         }
491         return 0;
492
493 err_modify:
494         ib_destroy_qp(p->qp);
495 err_qp:
496         kfree(p);
497         return ret;
498 }
499
500 static int ipoib_cm_rx_handler(struct ib_cm_id *cm_id,
501                                struct ib_cm_event *event)
502 {
503         struct ipoib_cm_rx *p;
504         struct ipoib_dev_priv *priv;
505
506         switch (event->event) {
507         case IB_CM_REQ_RECEIVED:
508                 return ipoib_cm_req_handler(cm_id, event);
509         case IB_CM_DREQ_RECEIVED:
510                 p = cm_id->context;
511                 ib_send_cm_drep(cm_id, NULL, 0);
512                 /* Fall through */
513         case IB_CM_REJ_RECEIVED:
514                 p = cm_id->context;
515                 priv = netdev_priv(p->dev);
516                 if (ib_modify_qp(p->qp, &ipoib_cm_err_attr, IB_QP_STATE))
517                         ipoib_warn(priv, "unable to move qp to error state\n");
518                 /* Fall through */
519         default:
520                 return 0;
521         }
522 }
523 /* Adjust length of skb with fragments to match received data */
524 static void skb_put_frags(struct sk_buff *skb, unsigned int hdr_space,
525                           unsigned int length, struct sk_buff *toskb)
526 {
527         int i, num_frags;
528         unsigned int size;
529
530         /* put header into skb */
531         size = min(length, hdr_space);
532         skb->tail += size;
533         skb->len += size;
534         length -= size;
535
536         num_frags = skb_shinfo(skb)->nr_frags;
537         for (i = 0; i < num_frags; i++) {
538                 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
539
540                 if (length == 0) {
541                         /* don't need this page */
542                         skb_fill_page_desc(toskb, i, frag->page, 0, PAGE_SIZE);
543                         --skb_shinfo(skb)->nr_frags;
544                 } else {
545                         size = min(length, (unsigned) PAGE_SIZE);
546
547                         frag->size = size;
548                         skb->data_len += size;
549                         skb->truesize += size;
550                         skb->len += size;
551                         length -= size;
552                 }
553         }
554 }
555
556 void ipoib_cm_handle_rx_wc(struct net_device *dev, struct ib_wc *wc)
557 {
558         struct ipoib_dev_priv *priv = netdev_priv(dev);
559         struct ipoib_cm_rx_buf *rx_ring;
560         unsigned int wr_id = wc->wr_id & ~(IPOIB_OP_CM | IPOIB_OP_RECV);
561         struct sk_buff *skb, *newskb;
562         struct ipoib_cm_rx *p;
563         unsigned long flags;
564         u64 mapping[IPOIB_CM_RX_SG];
565         int frags;
566         int has_srq;
567         struct sk_buff *small_skb;
568
569         ipoib_dbg_data(priv, "cm recv completion: id %d, status: %d\n",
570                        wr_id, wc->status);
571
572         if (unlikely(wr_id >= ipoib_recvq_size)) {
573                 if (wr_id == (IPOIB_CM_RX_DRAIN_WRID & ~(IPOIB_OP_CM | IPOIB_OP_RECV))) {
574                         spin_lock_irqsave(&priv->lock, flags);
575                         list_splice_init(&priv->cm.rx_drain_list, &priv->cm.rx_reap_list);
576                         ipoib_cm_start_rx_drain(priv);
577                         queue_work(ipoib_workqueue, &priv->cm.rx_reap_task);
578                         spin_unlock_irqrestore(&priv->lock, flags);
579                 } else
580                         ipoib_warn(priv, "cm recv completion event with wrid %d (> %d)\n",
581                                    wr_id, ipoib_recvq_size);
582                 return;
583         }
584
585         p = wc->qp->qp_context;
586
587         has_srq = ipoib_cm_has_srq(dev);
588         rx_ring = has_srq ? priv->cm.srq_ring : p->rx_ring;
589
590         skb = rx_ring[wr_id].skb;
591
592         if (unlikely(wc->status != IB_WC_SUCCESS)) {
593                 ipoib_dbg(priv, "cm recv error "
594                            "(status=%d, wrid=%d vend_err %x)\n",
595                            wc->status, wr_id, wc->vendor_err);
596                 ++dev->stats.rx_dropped;
597                 if (has_srq)
598                         goto repost;
599                 else {
600                         if (!--p->recv_count) {
601                                 spin_lock_irqsave(&priv->lock, flags);
602                                 list_move(&p->list, &priv->cm.rx_reap_list);
603                                 spin_unlock_irqrestore(&priv->lock, flags);
604                                 queue_work(ipoib_workqueue, &priv->cm.rx_reap_task);
605                         }
606                         return;
607                 }
608         }
609
610         if (unlikely(!(wr_id & IPOIB_CM_RX_UPDATE_MASK))) {
611                 if (p && time_after_eq(jiffies, p->jiffies + IPOIB_CM_RX_UPDATE_TIME)) {
612                         spin_lock_irqsave(&priv->lock, flags);
613                         p->jiffies = jiffies;
614                         /* Move this entry to list head, but do not re-add it
615                          * if it has been moved out of list. */
616                         if (p->state == IPOIB_CM_RX_LIVE)
617                                 list_move(&p->list, &priv->cm.passive_ids);
618                         spin_unlock_irqrestore(&priv->lock, flags);
619                 }
620         }
621
622         if (wc->byte_len < IPOIB_CM_COPYBREAK) {
623                 int dlen = wc->byte_len;
624
625                 small_skb = dev_alloc_skb(dlen + 12);
626                 if (small_skb) {
627                         skb_reserve(small_skb, 12);
628                         ib_dma_sync_single_for_cpu(priv->ca, rx_ring[wr_id].mapping[0],
629                                                    dlen, DMA_FROM_DEVICE);
630                         skb_copy_from_linear_data(skb, small_skb->data, dlen);
631                         ib_dma_sync_single_for_device(priv->ca, rx_ring[wr_id].mapping[0],
632                                                       dlen, DMA_FROM_DEVICE);
633                         skb_put(small_skb, dlen);
634                         skb = small_skb;
635                         goto copied;
636                 }
637         }
638
639         frags = PAGE_ALIGN(wc->byte_len - min(wc->byte_len,
640                                               (unsigned)IPOIB_CM_HEAD_SIZE)) / PAGE_SIZE;
641
642         newskb = ipoib_cm_alloc_rx_skb(dev, rx_ring, wr_id, frags, mapping);
643         if (unlikely(!newskb)) {
644                 /*
645                  * If we can't allocate a new RX buffer, dump
646                  * this packet and reuse the old buffer.
647                  */
648                 ipoib_dbg(priv, "failed to allocate receive buffer %d\n", wr_id);
649                 ++dev->stats.rx_dropped;
650                 goto repost;
651         }
652
653         ipoib_cm_dma_unmap_rx(priv, frags, rx_ring[wr_id].mapping);
654         memcpy(rx_ring[wr_id].mapping, mapping, (frags + 1) * sizeof *mapping);
655
656         ipoib_dbg_data(priv, "received %d bytes, SLID 0x%04x\n",
657                        wc->byte_len, wc->slid);
658
659         skb_put_frags(skb, IPOIB_CM_HEAD_SIZE, wc->byte_len, newskb);
660
661 copied:
662         skb->protocol = ((struct ipoib_header *) skb->data)->proto;
663         skb_reset_mac_header(skb);
664         skb_pull(skb, IPOIB_ENCAP_LEN);
665
666         dev->last_rx = jiffies;
667         ++dev->stats.rx_packets;
668         dev->stats.rx_bytes += skb->len;
669
670         skb->dev = dev;
671         /* XXX get correct PACKET_ type here */
672         skb->pkt_type = PACKET_HOST;
673         netif_receive_skb(skb);
674
675 repost:
676         if (has_srq) {
677                 if (unlikely(ipoib_cm_post_receive_srq(dev, wr_id)))
678                         ipoib_warn(priv, "ipoib_cm_post_receive_srq failed "
679                                    "for buf %d\n", wr_id);
680         } else {
681                 if (unlikely(ipoib_cm_post_receive_nonsrq(dev, p,
682                                                           &priv->cm.rx_wr,
683                                                           priv->cm.rx_sge,
684                                                           wr_id))) {
685                         --p->recv_count;
686                         ipoib_warn(priv, "ipoib_cm_post_receive_nonsrq failed "
687                                    "for buf %d\n", wr_id);
688                 }
689         }
690 }
691
692 static inline int post_send(struct ipoib_dev_priv *priv,
693                             struct ipoib_cm_tx *tx,
694                             unsigned int wr_id,
695                             u64 addr, int len)
696 {
697         struct ib_send_wr *bad_wr;
698
699         priv->tx_sge[0].addr          = addr;
700         priv->tx_sge[0].length        = len;
701
702         priv->tx_wr.num_sge     = 1;
703         priv->tx_wr.wr_id       = wr_id | IPOIB_OP_CM;
704
705         return ib_post_send(tx->qp, &priv->tx_wr, &bad_wr);
706 }
707
708 void ipoib_cm_send(struct net_device *dev, struct sk_buff *skb, struct ipoib_cm_tx *tx)
709 {
710         struct ipoib_dev_priv *priv = netdev_priv(dev);
711         struct ipoib_cm_tx_buf *tx_req;
712         u64 addr;
713
714         if (unlikely(skb->len > tx->mtu)) {
715                 ipoib_warn(priv, "packet len %d (> %d) too long to send, dropping\n",
716                            skb->len, tx->mtu);
717                 ++dev->stats.tx_dropped;
718                 ++dev->stats.tx_errors;
719                 ipoib_cm_skb_too_long(dev, skb, tx->mtu - IPOIB_ENCAP_LEN);
720                 return;
721         }
722
723         ipoib_dbg_data(priv, "sending packet: head 0x%x length %d connection 0x%x\n",
724                        tx->tx_head, skb->len, tx->qp->qp_num);
725
726         /*
727          * We put the skb into the tx_ring _before_ we call post_send()
728          * because it's entirely possible that the completion handler will
729          * run before we execute anything after the post_send().  That
730          * means we have to make sure everything is properly recorded and
731          * our state is consistent before we call post_send().
732          */
733         tx_req = &tx->tx_ring[tx->tx_head & (ipoib_sendq_size - 1)];
734         tx_req->skb = skb;
735         addr = ib_dma_map_single(priv->ca, skb->data, skb->len, DMA_TO_DEVICE);
736         if (unlikely(ib_dma_mapping_error(priv->ca, addr))) {
737                 ++dev->stats.tx_errors;
738                 dev_kfree_skb_any(skb);
739                 return;
740         }
741
742         tx_req->mapping = addr;
743
744         if (unlikely(post_send(priv, tx, tx->tx_head & (ipoib_sendq_size - 1),
745                                addr, skb->len))) {
746                 ipoib_warn(priv, "post_send failed\n");
747                 ++dev->stats.tx_errors;
748                 ib_dma_unmap_single(priv->ca, addr, skb->len, DMA_TO_DEVICE);
749                 dev_kfree_skb_any(skb);
750         } else {
751                 dev->trans_start = jiffies;
752                 ++tx->tx_head;
753
754                 if (++priv->tx_outstanding == ipoib_sendq_size) {
755                         ipoib_dbg(priv, "TX ring 0x%x full, stopping kernel net queue\n",
756                                   tx->qp->qp_num);
757                         netif_stop_queue(dev);
758                 }
759         }
760 }
761
762 void ipoib_cm_handle_tx_wc(struct net_device *dev, struct ib_wc *wc)
763 {
764         struct ipoib_dev_priv *priv = netdev_priv(dev);
765         struct ipoib_cm_tx *tx = wc->qp->qp_context;
766         unsigned int wr_id = wc->wr_id & ~IPOIB_OP_CM;
767         struct ipoib_cm_tx_buf *tx_req;
768         unsigned long flags;
769
770         ipoib_dbg_data(priv, "cm send completion: id %d, status: %d\n",
771                        wr_id, wc->status);
772
773         if (unlikely(wr_id >= ipoib_sendq_size)) {
774                 ipoib_warn(priv, "cm send completion event with wrid %d (> %d)\n",
775                            wr_id, ipoib_sendq_size);
776                 return;
777         }
778
779         tx_req = &tx->tx_ring[wr_id];
780
781         ib_dma_unmap_single(priv->ca, tx_req->mapping, tx_req->skb->len, DMA_TO_DEVICE);
782
783         /* FIXME: is this right? Shouldn't we only increment on success? */
784         ++dev->stats.tx_packets;
785         dev->stats.tx_bytes += tx_req->skb->len;
786
787         dev_kfree_skb_any(tx_req->skb);
788
789         spin_lock_irqsave(&priv->tx_lock, flags);
790         ++tx->tx_tail;
791         if (unlikely(--priv->tx_outstanding == ipoib_sendq_size >> 1) &&
792             netif_queue_stopped(dev) &&
793             test_bit(IPOIB_FLAG_ADMIN_UP, &priv->flags))
794                 netif_wake_queue(dev);
795
796         if (wc->status != IB_WC_SUCCESS &&
797             wc->status != IB_WC_WR_FLUSH_ERR) {
798                 struct ipoib_neigh *neigh;
799
800                 ipoib_dbg(priv, "failed cm send event "
801                            "(status=%d, wrid=%d vend_err %x)\n",
802                            wc->status, wr_id, wc->vendor_err);
803
804                 spin_lock(&priv->lock);
805                 neigh = tx->neigh;
806
807                 if (neigh) {
808                         neigh->cm = NULL;
809                         list_del(&neigh->list);
810                         if (neigh->ah)
811                                 ipoib_put_ah(neigh->ah);
812                         ipoib_neigh_free(dev, neigh);
813
814                         tx->neigh = NULL;
815                 }
816
817                 if (test_and_clear_bit(IPOIB_FLAG_INITIALIZED, &tx->flags)) {
818                         list_move(&tx->list, &priv->cm.reap_list);
819                         queue_work(ipoib_workqueue, &priv->cm.reap_task);
820                 }
821
822                 clear_bit(IPOIB_FLAG_OPER_UP, &tx->flags);
823
824                 spin_unlock(&priv->lock);
825         }
826
827         spin_unlock_irqrestore(&priv->tx_lock, flags);
828 }
829
830 int ipoib_cm_dev_open(struct net_device *dev)
831 {
832         struct ipoib_dev_priv *priv = netdev_priv(dev);
833         int ret;
834
835         if (!IPOIB_CM_SUPPORTED(dev->dev_addr))
836                 return 0;
837
838         priv->cm.id = ib_create_cm_id(priv->ca, ipoib_cm_rx_handler, dev);
839         if (IS_ERR(priv->cm.id)) {
840                 printk(KERN_WARNING "%s: failed to create CM ID\n", priv->ca->name);
841                 ret = PTR_ERR(priv->cm.id);
842                 goto err_cm;
843         }
844
845         ret = ib_cm_listen(priv->cm.id, cpu_to_be64(IPOIB_CM_IETF_ID | priv->qp->qp_num),
846                            0, NULL);
847         if (ret) {
848                 printk(KERN_WARNING "%s: failed to listen on ID 0x%llx\n", priv->ca->name,
849                        IPOIB_CM_IETF_ID | priv->qp->qp_num);
850                 goto err_listen;
851         }
852
853         return 0;
854
855 err_listen:
856         ib_destroy_cm_id(priv->cm.id);
857 err_cm:
858         priv->cm.id = NULL;
859         return ret;
860 }
861
862 static void ipoib_cm_free_rx_reap_list(struct net_device *dev)
863 {
864         struct ipoib_dev_priv *priv = netdev_priv(dev);
865         struct ipoib_cm_rx *rx, *n;
866         LIST_HEAD(list);
867
868         spin_lock_irq(&priv->lock);
869         list_splice_init(&priv->cm.rx_reap_list, &list);
870         spin_unlock_irq(&priv->lock);
871
872         list_for_each_entry_safe(rx, n, &list, list) {
873                 ib_destroy_cm_id(rx->id);
874                 ib_destroy_qp(rx->qp);
875                 if (!ipoib_cm_has_srq(dev)) {
876                         ipoib_cm_free_rx_ring(priv->dev, rx->rx_ring);
877                         spin_lock_irq(&priv->lock);
878                         --priv->cm.nonsrq_conn_qp;
879                         spin_unlock_irq(&priv->lock);
880                 }
881                 kfree(rx);
882         }
883 }
884
885 void ipoib_cm_dev_stop(struct net_device *dev)
886 {
887         struct ipoib_dev_priv *priv = netdev_priv(dev);
888         struct ipoib_cm_rx *p;
889         unsigned long begin;
890         int ret;
891
892         if (!IPOIB_CM_SUPPORTED(dev->dev_addr) || !priv->cm.id)
893                 return;
894
895         ib_destroy_cm_id(priv->cm.id);
896         priv->cm.id = NULL;
897
898         spin_lock_irq(&priv->lock);
899         while (!list_empty(&priv->cm.passive_ids)) {
900                 p = list_entry(priv->cm.passive_ids.next, typeof(*p), list);
901                 list_move(&p->list, &priv->cm.rx_error_list);
902                 p->state = IPOIB_CM_RX_ERROR;
903                 spin_unlock_irq(&priv->lock);
904                 ret = ib_modify_qp(p->qp, &ipoib_cm_err_attr, IB_QP_STATE);
905                 if (ret)
906                         ipoib_warn(priv, "unable to move qp to error state: %d\n", ret);
907                 spin_lock_irq(&priv->lock);
908         }
909
910         /* Wait for all RX to be drained */
911         begin = jiffies;
912
913         while (!list_empty(&priv->cm.rx_error_list) ||
914                !list_empty(&priv->cm.rx_flush_list) ||
915                !list_empty(&priv->cm.rx_drain_list)) {
916                 if (time_after(jiffies, begin + 5 * HZ)) {
917                         ipoib_warn(priv, "RX drain timing out\n");
918
919                         /*
920                          * assume the HW is wedged and just free up everything.
921                          */
922                         list_splice_init(&priv->cm.rx_flush_list,
923                                          &priv->cm.rx_reap_list);
924                         list_splice_init(&priv->cm.rx_error_list,
925                                          &priv->cm.rx_reap_list);
926                         list_splice_init(&priv->cm.rx_drain_list,
927                                          &priv->cm.rx_reap_list);
928                         break;
929                 }
930                 spin_unlock_irq(&priv->lock);
931                 msleep(1);
932                 ipoib_drain_cq(dev);
933                 spin_lock_irq(&priv->lock);
934         }
935
936         spin_unlock_irq(&priv->lock);
937
938         ipoib_cm_free_rx_reap_list(dev);
939
940         cancel_delayed_work(&priv->cm.stale_task);
941 }
942
943 static int ipoib_cm_rep_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event)
944 {
945         struct ipoib_cm_tx *p = cm_id->context;
946         struct ipoib_dev_priv *priv = netdev_priv(p->dev);
947         struct ipoib_cm_data *data = event->private_data;
948         struct sk_buff_head skqueue;
949         struct ib_qp_attr qp_attr;
950         int qp_attr_mask, ret;
951         struct sk_buff *skb;
952
953         p->mtu = be32_to_cpu(data->mtu);
954
955         if (p->mtu <= IPOIB_ENCAP_LEN) {
956                 ipoib_warn(priv, "Rejecting connection: mtu %d <= %d\n",
957                            p->mtu, IPOIB_ENCAP_LEN);
958                 return -EINVAL;
959         }
960
961         qp_attr.qp_state = IB_QPS_RTR;
962         ret = ib_cm_init_qp_attr(cm_id, &qp_attr, &qp_attr_mask);
963         if (ret) {
964                 ipoib_warn(priv, "failed to init QP attr for RTR: %d\n", ret);
965                 return ret;
966         }
967
968         qp_attr.rq_psn = 0 /* FIXME */;
969         ret = ib_modify_qp(p->qp, &qp_attr, qp_attr_mask);
970         if (ret) {
971                 ipoib_warn(priv, "failed to modify QP to RTR: %d\n", ret);
972                 return ret;
973         }
974
975         qp_attr.qp_state = IB_QPS_RTS;
976         ret = ib_cm_init_qp_attr(cm_id, &qp_attr, &qp_attr_mask);
977         if (ret) {
978                 ipoib_warn(priv, "failed to init QP attr for RTS: %d\n", ret);
979                 return ret;
980         }
981         ret = ib_modify_qp(p->qp, &qp_attr, qp_attr_mask);
982         if (ret) {
983                 ipoib_warn(priv, "failed to modify QP to RTS: %d\n", ret);
984                 return ret;
985         }
986
987         skb_queue_head_init(&skqueue);
988
989         spin_lock_irq(&priv->lock);
990         set_bit(IPOIB_FLAG_OPER_UP, &p->flags);
991         if (p->neigh)
992                 while ((skb = __skb_dequeue(&p->neigh->queue)))
993                         __skb_queue_tail(&skqueue, skb);
994         spin_unlock_irq(&priv->lock);
995
996         while ((skb = __skb_dequeue(&skqueue))) {
997                 skb->dev = p->dev;
998                 if (dev_queue_xmit(skb))
999                         ipoib_warn(priv, "dev_queue_xmit failed "
1000                                    "to requeue packet\n");
1001         }
1002
1003         ret = ib_send_cm_rtu(cm_id, NULL, 0);
1004         if (ret) {
1005                 ipoib_warn(priv, "failed to send RTU: %d\n", ret);
1006                 return ret;
1007         }
1008         return 0;
1009 }
1010
1011 static struct ib_qp *ipoib_cm_create_tx_qp(struct net_device *dev, struct ipoib_cm_tx *tx)
1012 {
1013         struct ipoib_dev_priv *priv = netdev_priv(dev);
1014         struct ib_qp_init_attr attr = {
1015                 .send_cq                = priv->recv_cq,
1016                 .recv_cq                = priv->recv_cq,
1017                 .srq                    = priv->cm.srq,
1018                 .cap.max_send_wr        = ipoib_sendq_size,
1019                 .cap.max_send_sge       = 1,
1020                 .sq_sig_type            = IB_SIGNAL_ALL_WR,
1021                 .qp_type                = IB_QPT_RC,
1022                 .qp_context             = tx
1023         };
1024
1025         return ib_create_qp(priv->pd, &attr);
1026 }
1027
1028 static int ipoib_cm_send_req(struct net_device *dev,
1029                              struct ib_cm_id *id, struct ib_qp *qp,
1030                              u32 qpn,
1031                              struct ib_sa_path_rec *pathrec)
1032 {
1033         struct ipoib_dev_priv *priv = netdev_priv(dev);
1034         struct ipoib_cm_data data = {};
1035         struct ib_cm_req_param req = {};
1036
1037         data.qpn = cpu_to_be32(priv->qp->qp_num);
1038         data.mtu = cpu_to_be32(IPOIB_CM_BUF_SIZE);
1039
1040         req.primary_path                = pathrec;
1041         req.alternate_path              = NULL;
1042         req.service_id                  = cpu_to_be64(IPOIB_CM_IETF_ID | qpn);
1043         req.qp_num                      = qp->qp_num;
1044         req.qp_type                     = qp->qp_type;
1045         req.private_data                = &data;
1046         req.private_data_len            = sizeof data;
1047         req.flow_control                = 0;
1048
1049         req.starting_psn                = 0; /* FIXME */
1050
1051         /*
1052          * Pick some arbitrary defaults here; we could make these
1053          * module parameters if anyone cared about setting them.
1054          */
1055         req.responder_resources         = 4;
1056         req.remote_cm_response_timeout  = 20;
1057         req.local_cm_response_timeout   = 20;
1058         req.retry_count                 = 0; /* RFC draft warns against retries */
1059         req.rnr_retry_count             = 0; /* RFC draft warns against retries */
1060         req.max_cm_retries              = 15;
1061         req.srq                         = ipoib_cm_has_srq(dev);
1062         return ib_send_cm_req(id, &req);
1063 }
1064
1065 static int ipoib_cm_modify_tx_init(struct net_device *dev,
1066                                   struct ib_cm_id *cm_id, struct ib_qp *qp)
1067 {
1068         struct ipoib_dev_priv *priv = netdev_priv(dev);
1069         struct ib_qp_attr qp_attr;
1070         int qp_attr_mask, ret;
1071         ret = ib_find_pkey(priv->ca, priv->port, priv->pkey, &qp_attr.pkey_index);
1072         if (ret) {
1073                 ipoib_warn(priv, "pkey 0x%x not found: %d\n", priv->pkey, ret);
1074                 return ret;
1075         }
1076
1077         qp_attr.qp_state = IB_QPS_INIT;
1078         qp_attr.qp_access_flags = IB_ACCESS_LOCAL_WRITE;
1079         qp_attr.port_num = priv->port;
1080         qp_attr_mask = IB_QP_STATE | IB_QP_ACCESS_FLAGS | IB_QP_PKEY_INDEX | IB_QP_PORT;
1081
1082         ret = ib_modify_qp(qp, &qp_attr, qp_attr_mask);
1083         if (ret) {
1084                 ipoib_warn(priv, "failed to modify tx QP to INIT: %d\n", ret);
1085                 return ret;
1086         }
1087         return 0;
1088 }
1089
1090 static int ipoib_cm_tx_init(struct ipoib_cm_tx *p, u32 qpn,
1091                             struct ib_sa_path_rec *pathrec)
1092 {
1093         struct ipoib_dev_priv *priv = netdev_priv(p->dev);
1094         int ret;
1095
1096         p->tx_ring = vmalloc(ipoib_sendq_size * sizeof *p->tx_ring);
1097         if (!p->tx_ring) {
1098                 ipoib_warn(priv, "failed to allocate tx ring\n");
1099                 ret = -ENOMEM;
1100                 goto err_tx;
1101         }
1102         memset(p->tx_ring, 0, ipoib_sendq_size * sizeof *p->tx_ring);
1103
1104         p->qp = ipoib_cm_create_tx_qp(p->dev, p);
1105         if (IS_ERR(p->qp)) {
1106                 ret = PTR_ERR(p->qp);
1107                 ipoib_warn(priv, "failed to allocate tx qp: %d\n", ret);
1108                 goto err_qp;
1109         }
1110
1111         p->id = ib_create_cm_id(priv->ca, ipoib_cm_tx_handler, p);
1112         if (IS_ERR(p->id)) {
1113                 ret = PTR_ERR(p->id);
1114                 ipoib_warn(priv, "failed to create tx cm id: %d\n", ret);
1115                 goto err_id;
1116         }
1117
1118         ret = ipoib_cm_modify_tx_init(p->dev, p->id,  p->qp);
1119         if (ret) {
1120                 ipoib_warn(priv, "failed to modify tx qp to rtr: %d\n", ret);
1121                 goto err_modify;
1122         }
1123
1124         ret = ipoib_cm_send_req(p->dev, p->id, p->qp, qpn, pathrec);
1125         if (ret) {
1126                 ipoib_warn(priv, "failed to send cm req: %d\n", ret);
1127                 goto err_send_cm;
1128         }
1129
1130         ipoib_dbg(priv, "Request connection 0x%x for gid " IPOIB_GID_FMT " qpn 0x%x\n",
1131                   p->qp->qp_num, IPOIB_GID_ARG(pathrec->dgid), qpn);
1132
1133         return 0;
1134
1135 err_send_cm:
1136 err_modify:
1137         ib_destroy_cm_id(p->id);
1138 err_id:
1139         p->id = NULL;
1140         ib_destroy_qp(p->qp);
1141 err_qp:
1142         p->qp = NULL;
1143         vfree(p->tx_ring);
1144 err_tx:
1145         return ret;
1146 }
1147
1148 static void ipoib_cm_tx_destroy(struct ipoib_cm_tx *p)
1149 {
1150         struct ipoib_dev_priv *priv = netdev_priv(p->dev);
1151         struct ipoib_cm_tx_buf *tx_req;
1152         unsigned long flags;
1153         unsigned long begin;
1154
1155         ipoib_dbg(priv, "Destroy active connection 0x%x head 0x%x tail 0x%x\n",
1156                   p->qp ? p->qp->qp_num : 0, p->tx_head, p->tx_tail);
1157
1158         if (p->id)
1159                 ib_destroy_cm_id(p->id);
1160
1161         if (p->tx_ring) {
1162                 /* Wait for all sends to complete */
1163                 begin = jiffies;
1164                 while ((int) p->tx_tail - (int) p->tx_head < 0) {
1165                         if (time_after(jiffies, begin + 5 * HZ)) {
1166                                 ipoib_warn(priv, "timing out; %d sends not completed\n",
1167                                            p->tx_head - p->tx_tail);
1168                                 goto timeout;
1169                         }
1170
1171                         msleep(1);
1172                 }
1173         }
1174
1175 timeout:
1176
1177         while ((int) p->tx_tail - (int) p->tx_head < 0) {
1178                 tx_req = &p->tx_ring[p->tx_tail & (ipoib_sendq_size - 1)];
1179                 ib_dma_unmap_single(priv->ca, tx_req->mapping, tx_req->skb->len,
1180                                     DMA_TO_DEVICE);
1181                 dev_kfree_skb_any(tx_req->skb);
1182                 ++p->tx_tail;
1183                 spin_lock_irqsave(&priv->tx_lock, flags);
1184                 if (unlikely(--priv->tx_outstanding == ipoib_sendq_size >> 1) &&
1185                     netif_queue_stopped(p->dev) &&
1186                     test_bit(IPOIB_FLAG_ADMIN_UP, &priv->flags))
1187                         netif_wake_queue(p->dev);
1188                 spin_unlock_irqrestore(&priv->tx_lock, flags);
1189         }
1190
1191         if (p->qp)
1192                 ib_destroy_qp(p->qp);
1193
1194         vfree(p->tx_ring);
1195         kfree(p);
1196 }
1197
1198 static int ipoib_cm_tx_handler(struct ib_cm_id *cm_id,
1199                                struct ib_cm_event *event)
1200 {
1201         struct ipoib_cm_tx *tx = cm_id->context;
1202         struct ipoib_dev_priv *priv = netdev_priv(tx->dev);
1203         struct net_device *dev = priv->dev;
1204         struct ipoib_neigh *neigh;
1205         int ret;
1206
1207         switch (event->event) {
1208         case IB_CM_DREQ_RECEIVED:
1209                 ipoib_dbg(priv, "DREQ received.\n");
1210                 ib_send_cm_drep(cm_id, NULL, 0);
1211                 break;
1212         case IB_CM_REP_RECEIVED:
1213                 ipoib_dbg(priv, "REP received.\n");
1214                 ret = ipoib_cm_rep_handler(cm_id, event);
1215                 if (ret)
1216                         ib_send_cm_rej(cm_id, IB_CM_REJ_CONSUMER_DEFINED,
1217                                        NULL, 0, NULL, 0);
1218                 break;
1219         case IB_CM_REQ_ERROR:
1220         case IB_CM_REJ_RECEIVED:
1221         case IB_CM_TIMEWAIT_EXIT:
1222                 ipoib_dbg(priv, "CM error %d.\n", event->event);
1223                 spin_lock_irq(&priv->tx_lock);
1224                 spin_lock(&priv->lock);
1225                 neigh = tx->neigh;
1226
1227                 if (neigh) {
1228                         neigh->cm = NULL;
1229                         list_del(&neigh->list);
1230                         if (neigh->ah)
1231                                 ipoib_put_ah(neigh->ah);
1232                         ipoib_neigh_free(dev, neigh);
1233
1234                         tx->neigh = NULL;
1235                 }
1236
1237                 if (test_and_clear_bit(IPOIB_FLAG_INITIALIZED, &tx->flags)) {
1238                         list_move(&tx->list, &priv->cm.reap_list);
1239                         queue_work(ipoib_workqueue, &priv->cm.reap_task);
1240                 }
1241
1242                 spin_unlock(&priv->lock);
1243                 spin_unlock_irq(&priv->tx_lock);
1244                 break;
1245         default:
1246                 break;
1247         }
1248
1249         return 0;
1250 }
1251
1252 struct ipoib_cm_tx *ipoib_cm_create_tx(struct net_device *dev, struct ipoib_path *path,
1253                                        struct ipoib_neigh *neigh)
1254 {
1255         struct ipoib_dev_priv *priv = netdev_priv(dev);
1256         struct ipoib_cm_tx *tx;
1257
1258         tx = kzalloc(sizeof *tx, GFP_ATOMIC);
1259         if (!tx)
1260                 return NULL;
1261
1262         neigh->cm = tx;
1263         tx->neigh = neigh;
1264         tx->path = path;
1265         tx->dev = dev;
1266         list_add(&tx->list, &priv->cm.start_list);
1267         set_bit(IPOIB_FLAG_INITIALIZED, &tx->flags);
1268         queue_work(ipoib_workqueue, &priv->cm.start_task);
1269         return tx;
1270 }
1271
1272 void ipoib_cm_destroy_tx(struct ipoib_cm_tx *tx)
1273 {
1274         struct ipoib_dev_priv *priv = netdev_priv(tx->dev);
1275         if (test_and_clear_bit(IPOIB_FLAG_INITIALIZED, &tx->flags)) {
1276                 list_move(&tx->list, &priv->cm.reap_list);
1277                 queue_work(ipoib_workqueue, &priv->cm.reap_task);
1278                 ipoib_dbg(priv, "Reap connection for gid " IPOIB_GID_FMT "\n",
1279                           IPOIB_GID_ARG(tx->neigh->dgid));
1280                 tx->neigh = NULL;
1281         }
1282 }
1283
1284 static void ipoib_cm_tx_start(struct work_struct *work)
1285 {
1286         struct ipoib_dev_priv *priv = container_of(work, struct ipoib_dev_priv,
1287                                                    cm.start_task);
1288         struct net_device *dev = priv->dev;
1289         struct ipoib_neigh *neigh;
1290         struct ipoib_cm_tx *p;
1291         unsigned long flags;
1292         int ret;
1293
1294         struct ib_sa_path_rec pathrec;
1295         u32 qpn;
1296
1297         spin_lock_irqsave(&priv->tx_lock, flags);
1298         spin_lock(&priv->lock);
1299         while (!list_empty(&priv->cm.start_list)) {
1300                 p = list_entry(priv->cm.start_list.next, typeof(*p), list);
1301                 list_del_init(&p->list);
1302                 neigh = p->neigh;
1303                 qpn = IPOIB_QPN(neigh->neighbour->ha);
1304                 memcpy(&pathrec, &p->path->pathrec, sizeof pathrec);
1305                 spin_unlock(&priv->lock);
1306                 spin_unlock_irqrestore(&priv->tx_lock, flags);
1307                 ret = ipoib_cm_tx_init(p, qpn, &pathrec);
1308                 spin_lock_irqsave(&priv->tx_lock, flags);
1309                 spin_lock(&priv->lock);
1310                 if (ret) {
1311                         neigh = p->neigh;
1312                         if (neigh) {
1313                                 neigh->cm = NULL;
1314                                 list_del(&neigh->list);
1315                                 if (neigh->ah)
1316                                         ipoib_put_ah(neigh->ah);
1317                                 ipoib_neigh_free(dev, neigh);
1318                         }
1319                         list_del(&p->list);
1320                         kfree(p);
1321                 }
1322         }
1323         spin_unlock(&priv->lock);
1324         spin_unlock_irqrestore(&priv->tx_lock, flags);
1325 }
1326
1327 static void ipoib_cm_tx_reap(struct work_struct *work)
1328 {
1329         struct ipoib_dev_priv *priv = container_of(work, struct ipoib_dev_priv,
1330                                                    cm.reap_task);
1331         struct ipoib_cm_tx *p;
1332
1333         spin_lock_irq(&priv->tx_lock);
1334         spin_lock(&priv->lock);
1335         while (!list_empty(&priv->cm.reap_list)) {
1336                 p = list_entry(priv->cm.reap_list.next, typeof(*p), list);
1337                 list_del(&p->list);
1338                 spin_unlock(&priv->lock);
1339                 spin_unlock_irq(&priv->tx_lock);
1340                 ipoib_cm_tx_destroy(p);
1341                 spin_lock_irq(&priv->tx_lock);
1342                 spin_lock(&priv->lock);
1343         }
1344         spin_unlock(&priv->lock);
1345         spin_unlock_irq(&priv->tx_lock);
1346 }
1347
1348 static void ipoib_cm_skb_reap(struct work_struct *work)
1349 {
1350         struct ipoib_dev_priv *priv = container_of(work, struct ipoib_dev_priv,
1351                                                    cm.skb_task);
1352         struct sk_buff *skb;
1353
1354         unsigned mtu = priv->mcast_mtu;
1355
1356         spin_lock_irq(&priv->tx_lock);
1357         spin_lock(&priv->lock);
1358         while ((skb = skb_dequeue(&priv->cm.skb_queue))) {
1359                 spin_unlock(&priv->lock);
1360                 spin_unlock_irq(&priv->tx_lock);
1361                 if (skb->protocol == htons(ETH_P_IP))
1362                         icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu));
1363 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
1364                 else if (skb->protocol == htons(ETH_P_IPV6))
1365                         icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, priv->dev);
1366 #endif
1367                 dev_kfree_skb_any(skb);
1368                 spin_lock_irq(&priv->tx_lock);
1369                 spin_lock(&priv->lock);
1370         }
1371         spin_unlock(&priv->lock);
1372         spin_unlock_irq(&priv->tx_lock);
1373 }
1374
1375 void ipoib_cm_skb_too_long(struct net_device *dev, struct sk_buff *skb,
1376                            unsigned int mtu)
1377 {
1378         struct ipoib_dev_priv *priv = netdev_priv(dev);
1379         int e = skb_queue_empty(&priv->cm.skb_queue);
1380
1381         if (skb->dst)
1382                 skb->dst->ops->update_pmtu(skb->dst, mtu);
1383
1384         skb_queue_tail(&priv->cm.skb_queue, skb);
1385         if (e)
1386                 queue_work(ipoib_workqueue, &priv->cm.skb_task);
1387 }
1388
1389 static void ipoib_cm_rx_reap(struct work_struct *work)
1390 {
1391         ipoib_cm_free_rx_reap_list(container_of(work, struct ipoib_dev_priv,
1392                                                 cm.rx_reap_task)->dev);
1393 }
1394
1395 static void ipoib_cm_stale_task(struct work_struct *work)
1396 {
1397         struct ipoib_dev_priv *priv = container_of(work, struct ipoib_dev_priv,
1398                                                    cm.stale_task.work);
1399         struct ipoib_cm_rx *p;
1400         int ret;
1401
1402         spin_lock_irq(&priv->lock);
1403         while (!list_empty(&priv->cm.passive_ids)) {
1404                 /* List is sorted by LRU, start from tail,
1405                  * stop when we see a recently used entry */
1406                 p = list_entry(priv->cm.passive_ids.prev, typeof(*p), list);
1407                 if (time_before_eq(jiffies, p->jiffies + IPOIB_CM_RX_TIMEOUT))
1408                         break;
1409                 list_move(&p->list, &priv->cm.rx_error_list);
1410                 p->state = IPOIB_CM_RX_ERROR;
1411                 spin_unlock_irq(&priv->lock);
1412                 ret = ib_modify_qp(p->qp, &ipoib_cm_err_attr, IB_QP_STATE);
1413                 if (ret)
1414                         ipoib_warn(priv, "unable to move qp to error state: %d\n", ret);
1415                 spin_lock_irq(&priv->lock);
1416         }
1417
1418         if (!list_empty(&priv->cm.passive_ids))
1419                 queue_delayed_work(ipoib_workqueue,
1420                                    &priv->cm.stale_task, IPOIB_CM_RX_DELAY);
1421         spin_unlock_irq(&priv->lock);
1422 }
1423
1424
1425 static ssize_t show_mode(struct device *d, struct device_attribute *attr,
1426                          char *buf)
1427 {
1428         struct ipoib_dev_priv *priv = netdev_priv(to_net_dev(d));
1429
1430         if (test_bit(IPOIB_FLAG_ADMIN_CM, &priv->flags))
1431                 return sprintf(buf, "connected\n");
1432         else
1433                 return sprintf(buf, "datagram\n");
1434 }
1435
1436 static ssize_t set_mode(struct device *d, struct device_attribute *attr,
1437                         const char *buf, size_t count)
1438 {
1439         struct net_device *dev = to_net_dev(d);
1440         struct ipoib_dev_priv *priv = netdev_priv(dev);
1441
1442         /* flush paths if we switch modes so that connections are restarted */
1443         if (IPOIB_CM_SUPPORTED(dev->dev_addr) && !strcmp(buf, "connected\n")) {
1444                 set_bit(IPOIB_FLAG_ADMIN_CM, &priv->flags);
1445                 ipoib_warn(priv, "enabling connected mode "
1446                            "will cause multicast packet drops\n");
1447
1448                 rtnl_lock();
1449                 dev->features &= ~(NETIF_F_IP_CSUM | NETIF_F_SG | NETIF_F_TSO);
1450                 rtnl_unlock();
1451                 priv->tx_wr.send_flags &= ~IB_SEND_IP_CSUM;
1452
1453                 ipoib_flush_paths(dev);
1454                 return count;
1455         }
1456
1457         if (!strcmp(buf, "datagram\n")) {
1458                 clear_bit(IPOIB_FLAG_ADMIN_CM, &priv->flags);
1459
1460                 rtnl_lock();
1461                 if (test_bit(IPOIB_FLAG_CSUM, &priv->flags)) {
1462                         dev->features |= NETIF_F_IP_CSUM | NETIF_F_SG;
1463                         if (priv->hca_caps & IB_DEVICE_UD_TSO)
1464                                 dev->features |= NETIF_F_TSO;
1465                 }
1466                 dev_set_mtu(dev, min(priv->mcast_mtu, dev->mtu));
1467                 rtnl_unlock();
1468                 ipoib_flush_paths(dev);
1469
1470                 return count;
1471         }
1472
1473         return -EINVAL;
1474 }
1475
1476 static DEVICE_ATTR(mode, S_IWUSR | S_IRUGO, show_mode, set_mode);
1477
1478 int ipoib_cm_add_mode_attr(struct net_device *dev)
1479 {
1480         return device_create_file(&dev->dev, &dev_attr_mode);
1481 }
1482
1483 static void ipoib_cm_create_srq(struct net_device *dev, int max_sge)
1484 {
1485         struct ipoib_dev_priv *priv = netdev_priv(dev);
1486         struct ib_srq_init_attr srq_init_attr = {
1487                 .attr = {
1488                         .max_wr  = ipoib_recvq_size,
1489                         .max_sge = max_sge
1490                 }
1491         };
1492
1493         priv->cm.srq = ib_create_srq(priv->pd, &srq_init_attr);
1494         if (IS_ERR(priv->cm.srq)) {
1495                 if (PTR_ERR(priv->cm.srq) != -ENOSYS)
1496                         printk(KERN_WARNING "%s: failed to allocate SRQ, error %ld\n",
1497                                priv->ca->name, PTR_ERR(priv->cm.srq));
1498                 priv->cm.srq = NULL;
1499                 return;
1500         }
1501
1502         priv->cm.srq_ring = vmalloc(ipoib_recvq_size * sizeof *priv->cm.srq_ring);
1503         if (!priv->cm.srq_ring) {
1504                 printk(KERN_WARNING "%s: failed to allocate CM SRQ ring (%d entries)\n",
1505                        priv->ca->name, ipoib_recvq_size);
1506                 ib_destroy_srq(priv->cm.srq);
1507                 priv->cm.srq = NULL;
1508                 return;
1509         }
1510
1511         memset(priv->cm.srq_ring, 0, ipoib_recvq_size * sizeof *priv->cm.srq_ring);
1512 }
1513
1514 int ipoib_cm_dev_init(struct net_device *dev)
1515 {
1516         struct ipoib_dev_priv *priv = netdev_priv(dev);
1517         int i, ret;
1518         struct ib_device_attr attr;
1519
1520         INIT_LIST_HEAD(&priv->cm.passive_ids);
1521         INIT_LIST_HEAD(&priv->cm.reap_list);
1522         INIT_LIST_HEAD(&priv->cm.start_list);
1523         INIT_LIST_HEAD(&priv->cm.rx_error_list);
1524         INIT_LIST_HEAD(&priv->cm.rx_flush_list);
1525         INIT_LIST_HEAD(&priv->cm.rx_drain_list);
1526         INIT_LIST_HEAD(&priv->cm.rx_reap_list);
1527         INIT_WORK(&priv->cm.start_task, ipoib_cm_tx_start);
1528         INIT_WORK(&priv->cm.reap_task, ipoib_cm_tx_reap);
1529         INIT_WORK(&priv->cm.skb_task, ipoib_cm_skb_reap);
1530         INIT_WORK(&priv->cm.rx_reap_task, ipoib_cm_rx_reap);
1531         INIT_DELAYED_WORK(&priv->cm.stale_task, ipoib_cm_stale_task);
1532
1533         skb_queue_head_init(&priv->cm.skb_queue);
1534
1535         ret = ib_query_device(priv->ca, &attr);
1536         if (ret) {
1537                 printk(KERN_WARNING "ib_query_device() failed with %d\n", ret);
1538                 return ret;
1539         }
1540
1541         ipoib_dbg(priv, "max_srq_sge=%d\n", attr.max_srq_sge);
1542
1543         attr.max_srq_sge = min_t(int, IPOIB_CM_RX_SG, attr.max_srq_sge);
1544         ipoib_cm_create_srq(dev, attr.max_srq_sge);
1545         if (ipoib_cm_has_srq(dev)) {
1546                 priv->cm.max_cm_mtu = attr.max_srq_sge * PAGE_SIZE - 0x10;
1547                 priv->cm.num_frags  = attr.max_srq_sge;
1548                 ipoib_dbg(priv, "max_cm_mtu = 0x%x, num_frags=%d\n",
1549                           priv->cm.max_cm_mtu, priv->cm.num_frags);
1550         } else {
1551                 priv->cm.max_cm_mtu = IPOIB_CM_MTU;
1552                 priv->cm.num_frags  = IPOIB_CM_RX_SG;
1553         }
1554
1555         ipoib_cm_init_rx_wr(dev, &priv->cm.rx_wr, priv->cm.rx_sge);
1556
1557         if (ipoib_cm_has_srq(dev)) {
1558                 for (i = 0; i < ipoib_recvq_size; ++i) {
1559                         if (!ipoib_cm_alloc_rx_skb(dev, priv->cm.srq_ring, i,
1560                                                    priv->cm.num_frags - 1,
1561                                                    priv->cm.srq_ring[i].mapping)) {
1562                                 ipoib_warn(priv, "failed to allocate "
1563                                            "receive buffer %d\n", i);
1564                                 ipoib_cm_dev_cleanup(dev);
1565                                 return -ENOMEM;
1566                         }
1567
1568                         if (ipoib_cm_post_receive_srq(dev, i)) {
1569                                 ipoib_warn(priv, "ipoib_cm_post_receive_srq "
1570                                            "failed for buf %d\n", i);
1571                                 ipoib_cm_dev_cleanup(dev);
1572                                 return -EIO;
1573                         }
1574                 }
1575         }
1576
1577         priv->dev->dev_addr[0] = IPOIB_FLAGS_RC;
1578         return 0;
1579 }
1580
1581 void ipoib_cm_dev_cleanup(struct net_device *dev)
1582 {
1583         struct ipoib_dev_priv *priv = netdev_priv(dev);
1584         int ret;
1585
1586         if (!priv->cm.srq)
1587                 return;
1588
1589         ipoib_dbg(priv, "Cleanup ipoib connected mode.\n");
1590
1591         ret = ib_destroy_srq(priv->cm.srq);
1592         if (ret)
1593                 ipoib_warn(priv, "ib_destroy_srq failed: %d\n", ret);
1594
1595         priv->cm.srq = NULL;
1596         if (!priv->cm.srq_ring)
1597                 return;
1598
1599         ipoib_cm_free_rx_ring(dev, priv->cm.srq_ring);
1600         priv->cm.srq_ring = NULL;
1601 }