1 /*
2  * Copyright (c) 2004, 2005 Topspin Communications.  All rights reserved.
3  * Copyright (c) 2005 Sun Microsystems, Inc. All rights reserved.
4  * Copyright (c) 2005 Mellanox Technologies. All rights reserved.
5  * Copyright (c) 2004, 2005 Voltaire, Inc. All rights reserved.
6  *
7  * This software is available to you under a choice of one of two
8  * licenses.  You may choose to be licensed under the terms of the GNU
9  * General Public License (GPL) Version 2, available from the file
10  * COPYING in the main directory of this source tree, or the
11  * OpenIB.org BSD license below:
12  *
13  *     Redistribution and use in source and binary forms, with or
14  *     without modification, are permitted provided that the following
15  *     conditions are met:
16  *
17  *      - Redistributions of source code must retain the above
18  *        copyright notice, this list of conditions and the following
19  *        disclaimer.
20  *
21  *      - Redistributions in binary form must reproduce the above
22  *        copyright notice, this list of conditions and the following
23  *        disclaimer in the documentation and/or other materials
24  *        provided with the distribution.
25  *
26  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
27  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
28  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
29  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
30  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
31  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
32  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
33  * SOFTWARE.
34  */
35 
36 #include <linux/delay.h>
37 #include <linux/dma-mapping.h>
38 
39 #include <rdma/ib_cache.h>
40 #include <linux/ip.h>
41 #include <linux/tcp.h>
42 
43 #include "ipoib.h"
44 
45 #ifdef CONFIG_INFINIBAND_IPOIB_DEBUG_DATA
46 static int data_debug_level;
47 
48 module_param(data_debug_level, int, 0644);
49 MODULE_PARM_DESC(data_debug_level,
50 		 "Enable data path debug tracing if > 0");
51 #endif
52 
53 static DEFINE_MUTEX(pkey_mutex);
54 
55 struct ipoib_ah *ipoib_create_ah(struct net_device *dev,
56 				 struct ib_pd *pd, struct ib_ah_attr *attr)
57 {
58 	struct ipoib_ah *ah;
59 
60 	ah = kmalloc(sizeof *ah, GFP_KERNEL);
61 	if (!ah)
62 		return NULL;
63 
64 	ah->dev       = dev;
65 	ah->last_send = 0;
66 	kref_init(&ah->ref);
67 
68 	ah->ah = ib_create_ah(pd, attr);
69 	if (IS_ERR(ah->ah)) {
70 		kfree(ah);
71 		ah = NULL;
72 	} else
73 		ipoib_dbg(netdev_priv(dev), "Created ah %p\n", ah->ah);
74 
75 	return ah;
76 }
77 
78 void ipoib_free_ah(struct kref *kref)
79 {
80 	struct ipoib_ah *ah = container_of(kref, struct ipoib_ah, ref);
81 	struct ipoib_dev_priv *priv = netdev_priv(ah->dev);
82 
83 	unsigned long flags;
84 
85 	spin_lock_irqsave(&priv->lock, flags);
86 	list_add_tail(&ah->list, &priv->dead_ahs);
87 	spin_unlock_irqrestore(&priv->lock, flags);
88 }
89 
90 static void ipoib_ud_dma_unmap_rx(struct ipoib_dev_priv *priv,
91 				  u64 mapping[IPOIB_UD_RX_SG])
92 {
93 	if (ipoib_ud_need_sg(priv->max_ib_mtu)) {
94 		ib_dma_unmap_single(priv->ca, mapping[0], IPOIB_UD_HEAD_SIZE,
95 				    DMA_FROM_DEVICE);
96 		ib_dma_unmap_page(priv->ca, mapping[1], PAGE_SIZE,
97 				  DMA_FROM_DEVICE);
98 	} else
99 		ib_dma_unmap_single(priv->ca, mapping[0],
100 				    IPOIB_UD_BUF_SIZE(priv->max_ib_mtu),
101 				    DMA_FROM_DEVICE);
102 }
103 
104 static void ipoib_ud_skb_put_frags(struct ipoib_dev_priv *priv,
105 				   struct sk_buff *skb,
106 				   unsigned int length)
107 {
108 	if (ipoib_ud_need_sg(priv->max_ib_mtu)) {
109 		skb_frag_t *frag = &skb_shinfo(skb)->frags[0];
110 		unsigned int size;
111 		/*
112 		 * There is only two buffers needed for max_payload = 4K,
113 		 * first buf size is IPOIB_UD_HEAD_SIZE
114 		 */
115 		skb->tail += IPOIB_UD_HEAD_SIZE;
116 		skb->len  += length;
117 
118 		size = length - IPOIB_UD_HEAD_SIZE;
119 
120 		frag->size     = size;
121 		skb->data_len += size;
122 		skb->truesize += size;
123 	} else
124 		skb_put(skb, length);
125 
126 }
127 
128 static int ipoib_ib_post_receive(struct net_device *dev, int id)
129 {
130 	struct ipoib_dev_priv *priv = netdev_priv(dev);
131 	struct ib_recv_wr *bad_wr;
132 	int ret;
133 
134 	priv->rx_wr.wr_id   = id | IPOIB_OP_RECV;
135 	priv->rx_sge[0].addr = priv->rx_ring[id].mapping[0];
136 	priv->rx_sge[1].addr = priv->rx_ring[id].mapping[1];
137 
138 
139 	ret = ib_post_recv(priv->qp, &priv->rx_wr, &bad_wr);
140 	if (unlikely(ret)) {
141 		ipoib_warn(priv, "receive failed for buf %d (%d)\n", id, ret);
142 		ipoib_ud_dma_unmap_rx(priv, priv->rx_ring[id].mapping);
143 		dev_kfree_skb_any(priv->rx_ring[id].skb);
144 		priv->rx_ring[id].skb = NULL;
145 	}
146 
147 	return ret;
148 }
149 
150 static struct sk_buff *ipoib_alloc_rx_skb(struct net_device *dev, int id)
151 {
152 	struct ipoib_dev_priv *priv = netdev_priv(dev);
153 	struct sk_buff *skb;
154 	int buf_size;
155 	u64 *mapping;
156 
157 	if (ipoib_ud_need_sg(priv->max_ib_mtu))
158 		buf_size = IPOIB_UD_HEAD_SIZE;
159 	else
160 		buf_size = IPOIB_UD_BUF_SIZE(priv->max_ib_mtu);
161 
162 	skb = dev_alloc_skb(buf_size + 4);
163 	if (unlikely(!skb))
164 		return NULL;
165 
166 	/*
167 	 * IB will leave a 40 byte gap for a GRH and IPoIB adds a 4 byte
168 	 * header.  So we need 4 more bytes to get to 48 and align the
169 	 * IP header to a multiple of 16.
170 	 */
171 	skb_reserve(skb, 4);
172 
173 	mapping = priv->rx_ring[id].mapping;
174 	mapping[0] = ib_dma_map_single(priv->ca, skb->data, buf_size,
175 				       DMA_FROM_DEVICE);
176 	if (unlikely(ib_dma_mapping_error(priv->ca, mapping[0])))
177 		goto error;
178 
179 	if (ipoib_ud_need_sg(priv->max_ib_mtu)) {
180 		struct page *page = alloc_page(GFP_ATOMIC);
181 		if (!page)
182 			goto partial_error;
183 		skb_fill_page_desc(skb, 0, page, 0, PAGE_SIZE);
184 		mapping[1] =
185 			ib_dma_map_page(priv->ca, skb_shinfo(skb)->frags[0].page,
186 					0, PAGE_SIZE, DMA_FROM_DEVICE);
187 		if (unlikely(ib_dma_mapping_error(priv->ca, mapping[1])))
188 			goto partial_error;
189 	}
190 
191 	priv->rx_ring[id].skb = skb;
192 	return skb;
193 
194 partial_error:
195 	ib_dma_unmap_single(priv->ca, mapping[0], buf_size, DMA_FROM_DEVICE);
196 error:
197 	dev_kfree_skb_any(skb);
198 	return NULL;
199 }
200 
201 static int ipoib_ib_post_receives(struct net_device *dev)
202 {
203 	struct ipoib_dev_priv *priv = netdev_priv(dev);
204 	int i;
205 
206 	for (i = 0; i < ipoib_recvq_size; ++i) {
207 		if (!ipoib_alloc_rx_skb(dev, i)) {
208 			ipoib_warn(priv, "failed to allocate receive buffer %d\n", i);
209 			return -ENOMEM;
210 		}
211 		if (ipoib_ib_post_receive(dev, i)) {
212 			ipoib_warn(priv, "ipoib_ib_post_receive failed for buf %d\n", i);
213 			return -EIO;
214 		}
215 	}
216 
217 	return 0;
218 }
219 
220 static void ipoib_ib_handle_rx_wc(struct net_device *dev, struct ib_wc *wc)
221 {
222 	struct ipoib_dev_priv *priv = netdev_priv(dev);
223 	unsigned int wr_id = wc->wr_id & ~IPOIB_OP_RECV;
224 	struct sk_buff *skb;
225 	u64 mapping[IPOIB_UD_RX_SG];
226 
227 	ipoib_dbg_data(priv, "recv completion: id %d, status: %d\n",
228 		       wr_id, wc->status);
229 
230 	if (unlikely(wr_id >= ipoib_recvq_size)) {
231 		ipoib_warn(priv, "recv completion event with wrid %d (> %d)\n",
232 			   wr_id, ipoib_recvq_size);
233 		return;
234 	}
235 
236 	skb  = priv->rx_ring[wr_id].skb;
237 
238 	if (unlikely(wc->status != IB_WC_SUCCESS)) {
239 		if (wc->status != IB_WC_WR_FLUSH_ERR)
240 			ipoib_warn(priv, "failed recv event "
241 				   "(status=%d, wrid=%d vend_err %x)\n",
242 				   wc->status, wr_id, wc->vendor_err);
243 		ipoib_ud_dma_unmap_rx(priv, priv->rx_ring[wr_id].mapping);
244 		dev_kfree_skb_any(skb);
245 		priv->rx_ring[wr_id].skb = NULL;
246 		return;
247 	}
248 
249 	/*
250 	 * Drop packets that this interface sent, ie multicast packets
251 	 * that the HCA has replicated.
252 	 */
253 	if (wc->slid == priv->local_lid && wc->src_qp == priv->qp->qp_num)
254 		goto repost;
255 
256 	memcpy(mapping, priv->rx_ring[wr_id].mapping,
257 	       IPOIB_UD_RX_SG * sizeof *mapping);
258 
259 	/*
260 	 * If we can't allocate a new RX buffer, dump
261 	 * this packet and reuse the old buffer.
262 	 */
263 	if (unlikely(!ipoib_alloc_rx_skb(dev, wr_id))) {
264 		++dev->stats.rx_dropped;
265 		goto repost;
266 	}
267 
268 	ipoib_dbg_data(priv, "received %d bytes, SLID 0x%04x\n",
269 		       wc->byte_len, wc->slid);
270 
271 	ipoib_ud_dma_unmap_rx(priv, mapping);
272 	ipoib_ud_skb_put_frags(priv, skb, wc->byte_len);
273 
274 	skb_pull(skb, IB_GRH_BYTES);
275 
276 	skb->protocol = ((struct ipoib_header *) skb->data)->proto;
277 	skb_reset_mac_header(skb);
278 	skb_pull(skb, IPOIB_ENCAP_LEN);
279 
280 	dev->last_rx = jiffies;
281 	++dev->stats.rx_packets;
282 	dev->stats.rx_bytes += skb->len;
283 
284 	skb->dev = dev;
285 	/* XXX get correct PACKET_ type here */
286 	skb->pkt_type = PACKET_HOST;
287 
288 	if (test_bit(IPOIB_FLAG_CSUM, &priv->flags) && likely(wc->csum_ok))
289 		skb->ip_summed = CHECKSUM_UNNECESSARY;
290 
291 	if (dev->features & NETIF_F_LRO)
292 		lro_receive_skb(&priv->lro.lro_mgr, skb, NULL);
293 	else
294 		netif_receive_skb(skb);
295 
296 repost:
297 	if (unlikely(ipoib_ib_post_receive(dev, wr_id)))
298 		ipoib_warn(priv, "ipoib_ib_post_receive failed "
299 			   "for buf %d\n", wr_id);
300 }
301 
302 static int ipoib_dma_map_tx(struct ib_device *ca,
303 			    struct ipoib_tx_buf *tx_req)
304 {
305 	struct sk_buff *skb = tx_req->skb;
306 	u64 *mapping = tx_req->mapping;
307 	int i;
308 	int off;
309 
310 	if (skb_headlen(skb)) {
311 		mapping[0] = ib_dma_map_single(ca, skb->data, skb_headlen(skb),
312 					       DMA_TO_DEVICE);
313 		if (unlikely(ib_dma_mapping_error(ca, mapping[0])))
314 			return -EIO;
315 
316 		off = 1;
317 	} else
318 		off = 0;
319 
320 	for (i = 0; i < skb_shinfo(skb)->nr_frags; ++i) {
321 		skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
322 		mapping[i + off] = ib_dma_map_page(ca, frag->page,
323 						 frag->page_offset, frag->size,
324 						 DMA_TO_DEVICE);
325 		if (unlikely(ib_dma_mapping_error(ca, mapping[i + off])))
326 			goto partial_error;
327 	}
328 	return 0;
329 
330 partial_error:
331 	for (; i > 0; --i) {
332 		skb_frag_t *frag = &skb_shinfo(skb)->frags[i - 1];
333 		ib_dma_unmap_page(ca, mapping[i - !off], frag->size, DMA_TO_DEVICE);
334 	}
335 
336 	if (off)
337 		ib_dma_unmap_single(ca, mapping[0], skb_headlen(skb), DMA_TO_DEVICE);
338 
339 	return -EIO;
340 }
341 
342 static void ipoib_dma_unmap_tx(struct ib_device *ca,
343 			       struct ipoib_tx_buf *tx_req)
344 {
345 	struct sk_buff *skb = tx_req->skb;
346 	u64 *mapping = tx_req->mapping;
347 	int i;
348 	int off;
349 
350 	if (skb_headlen(skb)) {
351 		ib_dma_unmap_single(ca, mapping[0], skb_headlen(skb), DMA_TO_DEVICE);
352 		off = 1;
353 	} else
354 		off = 0;
355 
356 	for (i = 0; i < skb_shinfo(skb)->nr_frags; ++i) {
357 		skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
358 		ib_dma_unmap_page(ca, mapping[i + off], frag->size,
359 				  DMA_TO_DEVICE);
360 	}
361 }
362 
363 static void ipoib_ib_handle_tx_wc(struct net_device *dev, struct ib_wc *wc)
364 {
365 	struct ipoib_dev_priv *priv = netdev_priv(dev);
366 	unsigned int wr_id = wc->wr_id;
367 	struct ipoib_tx_buf *tx_req;
368 
369 	ipoib_dbg_data(priv, "send completion: id %d, status: %d\n",
370 		       wr_id, wc->status);
371 
372 	if (unlikely(wr_id >= ipoib_sendq_size)) {
373 		ipoib_warn(priv, "send completion event with wrid %d (> %d)\n",
374 			   wr_id, ipoib_sendq_size);
375 		return;
376 	}
377 
378 	tx_req = &priv->tx_ring[wr_id];
379 
380 	ipoib_dma_unmap_tx(priv->ca, tx_req);
381 
382 	++dev->stats.tx_packets;
383 	dev->stats.tx_bytes += tx_req->skb->len;
384 
385 	dev_kfree_skb_any(tx_req->skb);
386 
387 	++priv->tx_tail;
388 	if (unlikely(--priv->tx_outstanding == ipoib_sendq_size >> 1) &&
389 	    netif_queue_stopped(dev) &&
390 	    test_bit(IPOIB_FLAG_ADMIN_UP, &priv->flags))
391 		netif_wake_queue(dev);
392 
393 	if (wc->status != IB_WC_SUCCESS &&
394 	    wc->status != IB_WC_WR_FLUSH_ERR)
395 		ipoib_warn(priv, "failed send event "
396 			   "(status=%d, wrid=%d vend_err %x)\n",
397 			   wc->status, wr_id, wc->vendor_err);
398 }
399 
400 static int poll_tx(struct ipoib_dev_priv *priv)
401 {
402 	int n, i;
403 
404 	n = ib_poll_cq(priv->send_cq, MAX_SEND_CQE, priv->send_wc);
405 	for (i = 0; i < n; ++i)
406 		ipoib_ib_handle_tx_wc(priv->dev, priv->send_wc + i);
407 
408 	return n == MAX_SEND_CQE;
409 }
410 
411 int ipoib_poll(struct napi_struct *napi, int budget)
412 {
413 	struct ipoib_dev_priv *priv = container_of(napi, struct ipoib_dev_priv, napi);
414 	struct net_device *dev = priv->dev;
415 	int done;
416 	int t;
417 	int n, i;
418 
419 	done  = 0;
420 
421 poll_more:
422 	while (done < budget) {
423 		int max = (budget - done);
424 
425 		t = min(IPOIB_NUM_WC, max);
426 		n = ib_poll_cq(priv->recv_cq, t, priv->ibwc);
427 
428 		for (i = 0; i < n; i++) {
429 			struct ib_wc *wc = priv->ibwc + i;
430 
431 			if (wc->wr_id & IPOIB_OP_RECV) {
432 				++done;
433 				if (wc->wr_id & IPOIB_OP_CM)
434 					ipoib_cm_handle_rx_wc(dev, wc);
435 				else
436 					ipoib_ib_handle_rx_wc(dev, wc);
437 			} else
438 				ipoib_cm_handle_tx_wc(priv->dev, wc);
439 		}
440 
441 		if (n != t)
442 			break;
443 	}
444 
445 	if (done < budget) {
446 		if (dev->features & NETIF_F_LRO)
447 			lro_flush_all(&priv->lro.lro_mgr);
448 
449 		netif_rx_complete(dev, napi);
450 		if (unlikely(ib_req_notify_cq(priv->recv_cq,
451 					      IB_CQ_NEXT_COMP |
452 					      IB_CQ_REPORT_MISSED_EVENTS)) &&
453 		    netif_rx_reschedule(dev, napi))
454 			goto poll_more;
455 	}
456 
457 	return done;
458 }
459 
460 void ipoib_ib_completion(struct ib_cq *cq, void *dev_ptr)
461 {
462 	struct net_device *dev = dev_ptr;
463 	struct ipoib_dev_priv *priv = netdev_priv(dev);
464 
465 	netif_rx_schedule(dev, &priv->napi);
466 }
467 
468 static void drain_tx_cq(struct net_device *dev)
469 {
470 	struct ipoib_dev_priv *priv = netdev_priv(dev);
471 
472 	netif_tx_lock(dev);
473 	while (poll_tx(priv))
474 		; /* nothing */
475 
476 	if (netif_queue_stopped(dev))
477 		mod_timer(&priv->poll_timer, jiffies + 1);
478 
479 	netif_tx_unlock(dev);
480 }
481 
482 void ipoib_send_comp_handler(struct ib_cq *cq, void *dev_ptr)
483 {
484 	struct ipoib_dev_priv *priv = netdev_priv(dev_ptr);
485 
486 	mod_timer(&priv->poll_timer, jiffies);
487 }
488 
489 static inline int post_send(struct ipoib_dev_priv *priv,
490 			    unsigned int wr_id,
491 			    struct ib_ah *address, u32 qpn,
492 			    struct ipoib_tx_buf *tx_req,
493 			    void *head, int hlen)
494 {
495 	struct ib_send_wr *bad_wr;
496 	int i, off;
497 	struct sk_buff *skb = tx_req->skb;
498 	skb_frag_t *frags = skb_shinfo(skb)->frags;
499 	int nr_frags = skb_shinfo(skb)->nr_frags;
500 	u64 *mapping = tx_req->mapping;
501 
502 	if (skb_headlen(skb)) {
503 		priv->tx_sge[0].addr         = mapping[0];
504 		priv->tx_sge[0].length       = skb_headlen(skb);
505 		off = 1;
506 	} else
507 		off = 0;
508 
509 	for (i = 0; i < nr_frags; ++i) {
510 		priv->tx_sge[i + off].addr = mapping[i + off];
511 		priv->tx_sge[i + off].length = frags[i].size;
512 	}
513 	priv->tx_wr.num_sge	     = nr_frags + off;
514 	priv->tx_wr.wr_id 	     = wr_id;
515 	priv->tx_wr.wr.ud.remote_qpn = qpn;
516 	priv->tx_wr.wr.ud.ah 	     = address;
517 
518 	if (head) {
519 		priv->tx_wr.wr.ud.mss	 = skb_shinfo(skb)->gso_size;
520 		priv->tx_wr.wr.ud.header = head;
521 		priv->tx_wr.wr.ud.hlen	 = hlen;
522 		priv->tx_wr.opcode	 = IB_WR_LSO;
523 	} else
524 		priv->tx_wr.opcode	 = IB_WR_SEND;
525 
526 	return ib_post_send(priv->qp, &priv->tx_wr, &bad_wr);
527 }
528 
529 void ipoib_send(struct net_device *dev, struct sk_buff *skb,
530 		struct ipoib_ah *address, u32 qpn)
531 {
532 	struct ipoib_dev_priv *priv = netdev_priv(dev);
533 	struct ipoib_tx_buf *tx_req;
534 	int hlen;
535 	void *phead;
536 
537 	if (skb_is_gso(skb)) {
538 		hlen = skb_transport_offset(skb) + tcp_hdrlen(skb);
539 		phead = skb->data;
540 		if (unlikely(!skb_pull(skb, hlen))) {
541 			ipoib_warn(priv, "linear data too small\n");
542 			++dev->stats.tx_dropped;
543 			++dev->stats.tx_errors;
544 			dev_kfree_skb_any(skb);
545 			return;
546 		}
547 	} else {
548 		if (unlikely(skb->len > priv->mcast_mtu + IPOIB_ENCAP_LEN)) {
549 			ipoib_warn(priv, "packet len %d (> %d) too long to send, dropping\n",
550 				   skb->len, priv->mcast_mtu + IPOIB_ENCAP_LEN);
551 			++dev->stats.tx_dropped;
552 			++dev->stats.tx_errors;
553 			ipoib_cm_skb_too_long(dev, skb, priv->mcast_mtu);
554 			return;
555 		}
556 		phead = NULL;
557 		hlen  = 0;
558 	}
559 
560 	ipoib_dbg_data(priv, "sending packet, length=%d address=%p qpn=0x%06x\n",
561 		       skb->len, address, qpn);
562 
563 	/*
564 	 * We put the skb into the tx_ring _before_ we call post_send()
565 	 * because it's entirely possible that the completion handler will
566 	 * run before we execute anything after the post_send().  That
567 	 * means we have to make sure everything is properly recorded and
568 	 * our state is consistent before we call post_send().
569 	 */
570 	tx_req = &priv->tx_ring[priv->tx_head & (ipoib_sendq_size - 1)];
571 	tx_req->skb = skb;
572 	if (unlikely(ipoib_dma_map_tx(priv->ca, tx_req))) {
573 		++dev->stats.tx_errors;
574 		dev_kfree_skb_any(skb);
575 		return;
576 	}
577 
578 	if (skb->ip_summed == CHECKSUM_PARTIAL)
579 		priv->tx_wr.send_flags |= IB_SEND_IP_CSUM;
580 	else
581 		priv->tx_wr.send_flags &= ~IB_SEND_IP_CSUM;
582 
583 	if (++priv->tx_outstanding == ipoib_sendq_size) {
584 		ipoib_dbg(priv, "TX ring full, stopping kernel net queue\n");
585 		if (ib_req_notify_cq(priv->send_cq, IB_CQ_NEXT_COMP))
586 			ipoib_warn(priv, "request notify on send CQ failed\n");
587 		netif_stop_queue(dev);
588 	}
589 
590 	if (unlikely(post_send(priv, priv->tx_head & (ipoib_sendq_size - 1),
591 			       address->ah, qpn, tx_req, phead, hlen))) {
592 		ipoib_warn(priv, "post_send failed\n");
593 		++dev->stats.tx_errors;
594 		--priv->tx_outstanding;
595 		ipoib_dma_unmap_tx(priv->ca, tx_req);
596 		dev_kfree_skb_any(skb);
597 		if (netif_queue_stopped(dev))
598 			netif_wake_queue(dev);
599 	} else {
600 		dev->trans_start = jiffies;
601 
602 		address->last_send = priv->tx_head;
603 		++priv->tx_head;
604 		skb_orphan(skb);
605 
606 	}
607 
608 	if (unlikely(priv->tx_outstanding > MAX_SEND_CQE))
609 		while (poll_tx(priv))
610 			; /* nothing */
611 }
612 
613 static void __ipoib_reap_ah(struct net_device *dev)
614 {
615 	struct ipoib_dev_priv *priv = netdev_priv(dev);
616 	struct ipoib_ah *ah, *tah;
617 	LIST_HEAD(remove_list);
618 	unsigned long flags;
619 
620 	netif_tx_lock_bh(dev);
621 	spin_lock_irqsave(&priv->lock, flags);
622 
623 	list_for_each_entry_safe(ah, tah, &priv->dead_ahs, list)
624 		if ((int) priv->tx_tail - (int) ah->last_send >= 0) {
625 			list_del(&ah->list);
626 			ib_destroy_ah(ah->ah);
627 			kfree(ah);
628 		}
629 
630 	spin_unlock_irqrestore(&priv->lock, flags);
631 	netif_tx_unlock_bh(dev);
632 }
633 
634 void ipoib_reap_ah(struct work_struct *work)
635 {
636 	struct ipoib_dev_priv *priv =
637 		container_of(work, struct ipoib_dev_priv, ah_reap_task.work);
638 	struct net_device *dev = priv->dev;
639 
640 	__ipoib_reap_ah(dev);
641 
642 	if (!test_bit(IPOIB_STOP_REAPER, &priv->flags))
643 		queue_delayed_work(ipoib_workqueue, &priv->ah_reap_task,
644 				   round_jiffies_relative(HZ));
645 }
646 
647 static void ipoib_ib_tx_timer_func(unsigned long ctx)
648 {
649 	drain_tx_cq((struct net_device *)ctx);
650 }
651 
652 int ipoib_ib_dev_open(struct net_device *dev)
653 {
654 	struct ipoib_dev_priv *priv = netdev_priv(dev);
655 	int ret;
656 
657 	if (ib_find_pkey(priv->ca, priv->port, priv->pkey, &priv->pkey_index)) {
658 		ipoib_warn(priv, "P_Key 0x%04x not found\n", priv->pkey);
659 		clear_bit(IPOIB_PKEY_ASSIGNED, &priv->flags);
660 		return -1;
661 	}
662 	set_bit(IPOIB_PKEY_ASSIGNED, &priv->flags);
663 
664 	ret = ipoib_init_qp(dev);
665 	if (ret) {
666 		ipoib_warn(priv, "ipoib_init_qp returned %d\n", ret);
667 		return -1;
668 	}
669 
670 	ret = ipoib_ib_post_receives(dev);
671 	if (ret) {
672 		ipoib_warn(priv, "ipoib_ib_post_receives returned %d\n", ret);
673 		ipoib_ib_dev_stop(dev, 1);
674 		return -1;
675 	}
676 
677 	ret = ipoib_cm_dev_open(dev);
678 	if (ret) {
679 		ipoib_warn(priv, "ipoib_cm_dev_open returned %d\n", ret);
680 		ipoib_ib_dev_stop(dev, 1);
681 		return -1;
682 	}
683 
684 	clear_bit(IPOIB_STOP_REAPER, &priv->flags);
685 	queue_delayed_work(ipoib_workqueue, &priv->ah_reap_task,
686 			   round_jiffies_relative(HZ));
687 
688 	set_bit(IPOIB_FLAG_INITIALIZED, &priv->flags);
689 
690 	return 0;
691 }
692 
693 static void ipoib_pkey_dev_check_presence(struct net_device *dev)
694 {
695 	struct ipoib_dev_priv *priv = netdev_priv(dev);
696 	u16 pkey_index = 0;
697 
698 	if (ib_find_pkey(priv->ca, priv->port, priv->pkey, &pkey_index))
699 		clear_bit(IPOIB_PKEY_ASSIGNED, &priv->flags);
700 	else
701 		set_bit(IPOIB_PKEY_ASSIGNED, &priv->flags);
702 }
703 
704 int ipoib_ib_dev_up(struct net_device *dev)
705 {
706 	struct ipoib_dev_priv *priv = netdev_priv(dev);
707 
708 	ipoib_pkey_dev_check_presence(dev);
709 
710 	if (!test_bit(IPOIB_PKEY_ASSIGNED, &priv->flags)) {
711 		ipoib_dbg(priv, "PKEY is not assigned.\n");
712 		return 0;
713 	}
714 
715 	set_bit(IPOIB_FLAG_OPER_UP, &priv->flags);
716 
717 	return ipoib_mcast_start_thread(dev);
718 }
719 
720 int ipoib_ib_dev_down(struct net_device *dev, int flush)
721 {
722 	struct ipoib_dev_priv *priv = netdev_priv(dev);
723 
724 	ipoib_dbg(priv, "downing ib_dev\n");
725 
726 	clear_bit(IPOIB_FLAG_OPER_UP, &priv->flags);
727 	netif_carrier_off(dev);
728 
729 	/* Shutdown the P_Key thread if still active */
730 	if (!test_bit(IPOIB_PKEY_ASSIGNED, &priv->flags)) {
731 		mutex_lock(&pkey_mutex);
732 		set_bit(IPOIB_PKEY_STOP, &priv->flags);
733 		cancel_delayed_work(&priv->pkey_poll_task);
734 		mutex_unlock(&pkey_mutex);
735 		if (flush)
736 			flush_workqueue(ipoib_workqueue);
737 	}
738 
739 	ipoib_mcast_stop_thread(dev, flush);
740 	ipoib_mcast_dev_flush(dev);
741 
742 	ipoib_flush_paths(dev);
743 
744 	return 0;
745 }
746 
747 static int recvs_pending(struct net_device *dev)
748 {
749 	struct ipoib_dev_priv *priv = netdev_priv(dev);
750 	int pending = 0;
751 	int i;
752 
753 	for (i = 0; i < ipoib_recvq_size; ++i)
754 		if (priv->rx_ring[i].skb)
755 			++pending;
756 
757 	return pending;
758 }
759 
760 void ipoib_drain_cq(struct net_device *dev)
761 {
762 	struct ipoib_dev_priv *priv = netdev_priv(dev);
763 	int i, n;
764 
765 	/*
766 	 * We call completion handling routines that expect to be
767 	 * called from the BH-disabled NAPI poll context, so disable
768 	 * BHs here too.
769 	 */
770 	local_bh_disable();
771 
772 	do {
773 		n = ib_poll_cq(priv->recv_cq, IPOIB_NUM_WC, priv->ibwc);
774 		for (i = 0; i < n; ++i) {
775 			/*
776 			 * Convert any successful completions to flush
777 			 * errors to avoid passing packets up the
778 			 * stack after bringing the device down.
779 			 */
780 			if (priv->ibwc[i].status == IB_WC_SUCCESS)
781 				priv->ibwc[i].status = IB_WC_WR_FLUSH_ERR;
782 
783 			if (priv->ibwc[i].wr_id & IPOIB_OP_RECV) {
784 				if (priv->ibwc[i].wr_id & IPOIB_OP_CM)
785 					ipoib_cm_handle_rx_wc(dev, priv->ibwc + i);
786 				else
787 					ipoib_ib_handle_rx_wc(dev, priv->ibwc + i);
788 			} else
789 				ipoib_cm_handle_tx_wc(dev, priv->ibwc + i);
790 		}
791 	} while (n == IPOIB_NUM_WC);
792 
793 	while (poll_tx(priv))
794 		; /* nothing */
795 
796 	local_bh_enable();
797 }
798 
799 int ipoib_ib_dev_stop(struct net_device *dev, int flush)
800 {
801 	struct ipoib_dev_priv *priv = netdev_priv(dev);
802 	struct ib_qp_attr qp_attr;
803 	unsigned long begin;
804 	struct ipoib_tx_buf *tx_req;
805 	int i;
806 
807 	clear_bit(IPOIB_FLAG_INITIALIZED, &priv->flags);
808 
809 	ipoib_cm_dev_stop(dev);
810 
811 	/*
812 	 * Move our QP to the error state and then reinitialize in
813 	 * when all work requests have completed or have been flushed.
814 	 */
815 	qp_attr.qp_state = IB_QPS_ERR;
816 	if (ib_modify_qp(priv->qp, &qp_attr, IB_QP_STATE))
817 		ipoib_warn(priv, "Failed to modify QP to ERROR state\n");
818 
819 	/* Wait for all sends and receives to complete */
820 	begin = jiffies;
821 
822 	while (priv->tx_head != priv->tx_tail || recvs_pending(dev)) {
823 		if (time_after(jiffies, begin + 5 * HZ)) {
824 			ipoib_warn(priv, "timing out; %d sends %d receives not completed\n",
825 				   priv->tx_head - priv->tx_tail, recvs_pending(dev));
826 
827 			/*
828 			 * assume the HW is wedged and just free up
829 			 * all our pending work requests.
830 			 */
831 			while ((int) priv->tx_tail - (int) priv->tx_head < 0) {
832 				tx_req = &priv->tx_ring[priv->tx_tail &
833 							(ipoib_sendq_size - 1)];
834 				ipoib_dma_unmap_tx(priv->ca, tx_req);
835 				dev_kfree_skb_any(tx_req->skb);
836 				++priv->tx_tail;
837 				--priv->tx_outstanding;
838 			}
839 
840 			for (i = 0; i < ipoib_recvq_size; ++i) {
841 				struct ipoib_rx_buf *rx_req;
842 
843 				rx_req = &priv->rx_ring[i];
844 				if (!rx_req->skb)
845 					continue;
846 				ipoib_ud_dma_unmap_rx(priv,
847 						      priv->rx_ring[i].mapping);
848 				dev_kfree_skb_any(rx_req->skb);
849 				rx_req->skb = NULL;
850 			}
851 
852 			goto timeout;
853 		}
854 
855 		ipoib_drain_cq(dev);
856 
857 		msleep(1);
858 	}
859 
860 	ipoib_dbg(priv, "All sends and receives done.\n");
861 
862 timeout:
863 	del_timer_sync(&priv->poll_timer);
864 	qp_attr.qp_state = IB_QPS_RESET;
865 	if (ib_modify_qp(priv->qp, &qp_attr, IB_QP_STATE))
866 		ipoib_warn(priv, "Failed to modify QP to RESET state\n");
867 
868 	/* Wait for all AHs to be reaped */
869 	set_bit(IPOIB_STOP_REAPER, &priv->flags);
870 	cancel_delayed_work(&priv->ah_reap_task);
871 	if (flush)
872 		flush_workqueue(ipoib_workqueue);
873 
874 	begin = jiffies;
875 
876 	while (!list_empty(&priv->dead_ahs)) {
877 		__ipoib_reap_ah(dev);
878 
879 		if (time_after(jiffies, begin + HZ)) {
880 			ipoib_warn(priv, "timing out; will leak address handles\n");
881 			break;
882 		}
883 
884 		msleep(1);
885 	}
886 
887 	ib_req_notify_cq(priv->recv_cq, IB_CQ_NEXT_COMP);
888 
889 	return 0;
890 }
891 
892 int ipoib_ib_dev_init(struct net_device *dev, struct ib_device *ca, int port)
893 {
894 	struct ipoib_dev_priv *priv = netdev_priv(dev);
895 
896 	priv->ca = ca;
897 	priv->port = port;
898 	priv->qp = NULL;
899 
900 	if (ipoib_transport_dev_init(dev, ca)) {
901 		printk(KERN_WARNING "%s: ipoib_transport_dev_init failed\n", ca->name);
902 		return -ENODEV;
903 	}
904 
905 	setup_timer(&priv->poll_timer, ipoib_ib_tx_timer_func,
906 		    (unsigned long) dev);
907 
908 	if (dev->flags & IFF_UP) {
909 		if (ipoib_ib_dev_open(dev)) {
910 			ipoib_transport_dev_cleanup(dev);
911 			return -ENODEV;
912 		}
913 	}
914 
915 	return 0;
916 }
917 
918 static void __ipoib_ib_dev_flush(struct ipoib_dev_priv *priv,
919 				enum ipoib_flush_level level)
920 {
921 	struct ipoib_dev_priv *cpriv;
922 	struct net_device *dev = priv->dev;
923 	u16 new_index;
924 
925 	mutex_lock(&priv->vlan_mutex);
926 
927 	/*
928 	 * Flush any child interfaces too -- they might be up even if
929 	 * the parent is down.
930 	 */
931 	list_for_each_entry(cpriv, &priv->child_intfs, list)
932 		__ipoib_ib_dev_flush(cpriv, level);
933 
934 	mutex_unlock(&priv->vlan_mutex);
935 
936 	if (!test_bit(IPOIB_FLAG_INITIALIZED, &priv->flags)) {
937 		ipoib_dbg(priv, "Not flushing - IPOIB_FLAG_INITIALIZED not set.\n");
938 		return;
939 	}
940 
941 	if (!test_bit(IPOIB_FLAG_ADMIN_UP, &priv->flags)) {
942 		ipoib_dbg(priv, "Not flushing - IPOIB_FLAG_ADMIN_UP not set.\n");
943 		return;
944 	}
945 
946 	if (level == IPOIB_FLUSH_HEAVY) {
947 		if (ib_find_pkey(priv->ca, priv->port, priv->pkey, &new_index)) {
948 			clear_bit(IPOIB_PKEY_ASSIGNED, &priv->flags);
949 			ipoib_ib_dev_down(dev, 0);
950 			ipoib_ib_dev_stop(dev, 0);
951 			if (ipoib_pkey_dev_delay_open(dev))
952 				return;
953 		}
954 
955 		/* restart QP only if P_Key index is changed */
956 		if (test_and_set_bit(IPOIB_PKEY_ASSIGNED, &priv->flags) &&
957 		    new_index == priv->pkey_index) {
958 			ipoib_dbg(priv, "Not flushing - P_Key index not changed.\n");
959 			return;
960 		}
961 		priv->pkey_index = new_index;
962 	}
963 
964 	if (level == IPOIB_FLUSH_LIGHT) {
965 		ipoib_mark_paths_invalid(dev);
966 		ipoib_mcast_dev_flush(dev);
967 	}
968 
969 	if (level >= IPOIB_FLUSH_NORMAL)
970 		ipoib_ib_dev_down(dev, 0);
971 
972 	if (level == IPOIB_FLUSH_HEAVY) {
973 		ipoib_ib_dev_stop(dev, 0);
974 		ipoib_ib_dev_open(dev);
975 	}
976 
977 	/*
978 	 * The device could have been brought down between the start and when
979 	 * we get here, don't bring it back up if it's not configured up
980 	 */
981 	if (test_bit(IPOIB_FLAG_ADMIN_UP, &priv->flags)) {
982 		if (level >= IPOIB_FLUSH_NORMAL)
983 			ipoib_ib_dev_up(dev);
984 		ipoib_mcast_restart_task(&priv->restart_task);
985 	}
986 }
987 
988 void ipoib_ib_dev_flush_light(struct work_struct *work)
989 {
990 	struct ipoib_dev_priv *priv =
991 		container_of(work, struct ipoib_dev_priv, flush_light);
992 
993 	__ipoib_ib_dev_flush(priv, IPOIB_FLUSH_LIGHT);
994 }
995 
996 void ipoib_ib_dev_flush_normal(struct work_struct *work)
997 {
998 	struct ipoib_dev_priv *priv =
999 		container_of(work, struct ipoib_dev_priv, flush_normal);
1000 
1001 	__ipoib_ib_dev_flush(priv, IPOIB_FLUSH_NORMAL);
1002 }
1003 
1004 void ipoib_ib_dev_flush_heavy(struct work_struct *work)
1005 {
1006 	struct ipoib_dev_priv *priv =
1007 		container_of(work, struct ipoib_dev_priv, flush_heavy);
1008 
1009 	__ipoib_ib_dev_flush(priv, IPOIB_FLUSH_HEAVY);
1010 }
1011 
1012 void ipoib_ib_dev_cleanup(struct net_device *dev)
1013 {
1014 	struct ipoib_dev_priv *priv = netdev_priv(dev);
1015 
1016 	ipoib_dbg(priv, "cleaning up ib_dev\n");
1017 
1018 	ipoib_mcast_stop_thread(dev, 1);
1019 	ipoib_mcast_dev_flush(dev);
1020 
1021 	ipoib_transport_dev_cleanup(dev);
1022 }
1023 
1024 /*
1025  * Delayed P_Key Assigment Interim Support
1026  *
1027  * The following is initial implementation of delayed P_Key assigment
1028  * mechanism. It is using the same approach implemented for the multicast
1029  * group join. The single goal of this implementation is to quickly address
1030  * Bug #2507. This implementation will probably be removed when the P_Key
1031  * change async notification is available.
1032  */
1033 
1034 void ipoib_pkey_poll(struct work_struct *work)
1035 {
1036 	struct ipoib_dev_priv *priv =
1037 		container_of(work, struct ipoib_dev_priv, pkey_poll_task.work);
1038 	struct net_device *dev = priv->dev;
1039 
1040 	ipoib_pkey_dev_check_presence(dev);
1041 
1042 	if (test_bit(IPOIB_PKEY_ASSIGNED, &priv->flags))
1043 		ipoib_open(dev);
1044 	else {
1045 		mutex_lock(&pkey_mutex);
1046 		if (!test_bit(IPOIB_PKEY_STOP, &priv->flags))
1047 			queue_delayed_work(ipoib_workqueue,
1048 					   &priv->pkey_poll_task,
1049 					   HZ);
1050 		mutex_unlock(&pkey_mutex);
1051 	}
1052 }
1053 
1054 int ipoib_pkey_dev_delay_open(struct net_device *dev)
1055 {
1056 	struct ipoib_dev_priv *priv = netdev_priv(dev);
1057 
1058 	/* Look for the interface pkey value in the IB Port P_Key table and */
1059 	/* set the interface pkey assigment flag                            */
1060 	ipoib_pkey_dev_check_presence(dev);
1061 
1062 	/* P_Key value not assigned yet - start polling */
1063 	if (!test_bit(IPOIB_PKEY_ASSIGNED, &priv->flags)) {
1064 		mutex_lock(&pkey_mutex);
1065 		clear_bit(IPOIB_PKEY_STOP, &priv->flags);
1066 		queue_delayed_work(ipoib_workqueue,
1067 				   &priv->pkey_poll_task,
1068 				   HZ);
1069 		mutex_unlock(&pkey_mutex);
1070 		return 1;
1071 	}
1072 
1073 	return 0;
1074 }
1075