1 /*
2  * Copyright (c) 2009-2010 Chelsio, Inc. 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 #include <linux/module.h>
33 #include <linux/moduleparam.h>
34 #include <linux/debugfs.h>
35 #include <linux/vmalloc.h>
36 
37 #include <rdma/ib_verbs.h>
38 
39 #include "iw_cxgb4.h"
40 
41 #define DRV_VERSION "0.1"
42 
43 MODULE_AUTHOR("Steve Wise");
44 MODULE_DESCRIPTION("Chelsio T4/T5 RDMA Driver");
45 MODULE_LICENSE("Dual BSD/GPL");
46 MODULE_VERSION(DRV_VERSION);
47 
48 static int allow_db_fc_on_t5;
49 module_param(allow_db_fc_on_t5, int, 0644);
50 MODULE_PARM_DESC(allow_db_fc_on_t5,
51 		 "Allow DB Flow Control on T5 (default = 0)");
52 
53 static int allow_db_coalescing_on_t5;
54 module_param(allow_db_coalescing_on_t5, int, 0644);
55 MODULE_PARM_DESC(allow_db_coalescing_on_t5,
56 		 "Allow DB Coalescing on T5 (default = 0)");
57 
58 struct uld_ctx {
59 	struct list_head entry;
60 	struct cxgb4_lld_info lldi;
61 	struct c4iw_dev *dev;
62 };
63 
64 static LIST_HEAD(uld_ctx_list);
65 static DEFINE_MUTEX(dev_mutex);
66 
67 #define DB_FC_RESUME_SIZE 64
68 #define DB_FC_RESUME_DELAY 1
69 #define DB_FC_DRAIN_THRESH 0
70 
71 static struct dentry *c4iw_debugfs_root;
72 
73 struct c4iw_debugfs_data {
74 	struct c4iw_dev *devp;
75 	char *buf;
76 	int bufsize;
77 	int pos;
78 };
79 
80 static int count_idrs(int id, void *p, void *data)
81 {
82 	int *countp = data;
83 
84 	*countp = *countp + 1;
85 	return 0;
86 }
87 
88 static ssize_t debugfs_read(struct file *file, char __user *buf, size_t count,
89 			    loff_t *ppos)
90 {
91 	struct c4iw_debugfs_data *d = file->private_data;
92 
93 	return simple_read_from_buffer(buf, count, ppos, d->buf, d->pos);
94 }
95 
96 static int dump_qp(int id, void *p, void *data)
97 {
98 	struct c4iw_qp *qp = p;
99 	struct c4iw_debugfs_data *qpd = data;
100 	int space;
101 	int cc;
102 
103 	if (id != qp->wq.sq.qid)
104 		return 0;
105 
106 	space = qpd->bufsize - qpd->pos - 1;
107 	if (space == 0)
108 		return 1;
109 
110 	if (qp->ep) {
111 		if (qp->ep->com.local_addr.ss_family == AF_INET) {
112 			struct sockaddr_in *lsin = (struct sockaddr_in *)
113 				&qp->ep->com.local_addr;
114 			struct sockaddr_in *rsin = (struct sockaddr_in *)
115 				&qp->ep->com.remote_addr;
116 
117 			cc = snprintf(qpd->buf + qpd->pos, space,
118 				      "rc qp sq id %u rq id %u state %u "
119 				      "onchip %u ep tid %u state %u "
120 				      "%pI4:%u->%pI4:%u\n",
121 				      qp->wq.sq.qid, qp->wq.rq.qid,
122 				      (int)qp->attr.state,
123 				      qp->wq.sq.flags & T4_SQ_ONCHIP,
124 				      qp->ep->hwtid, (int)qp->ep->com.state,
125 				      &lsin->sin_addr, ntohs(lsin->sin_port),
126 				      &rsin->sin_addr, ntohs(rsin->sin_port));
127 		} else {
128 			struct sockaddr_in6 *lsin6 = (struct sockaddr_in6 *)
129 				&qp->ep->com.local_addr;
130 			struct sockaddr_in6 *rsin6 = (struct sockaddr_in6 *)
131 				&qp->ep->com.remote_addr;
132 
133 			cc = snprintf(qpd->buf + qpd->pos, space,
134 				      "rc qp sq id %u rq id %u state %u "
135 				      "onchip %u ep tid %u state %u "
136 				      "%pI6:%u->%pI6:%u\n",
137 				      qp->wq.sq.qid, qp->wq.rq.qid,
138 				      (int)qp->attr.state,
139 				      qp->wq.sq.flags & T4_SQ_ONCHIP,
140 				      qp->ep->hwtid, (int)qp->ep->com.state,
141 				      &lsin6->sin6_addr,
142 				      ntohs(lsin6->sin6_port),
143 				      &rsin6->sin6_addr,
144 				      ntohs(rsin6->sin6_port));
145 		}
146 	} else
147 		cc = snprintf(qpd->buf + qpd->pos, space,
148 			     "qp sq id %u rq id %u state %u onchip %u\n",
149 			      qp->wq.sq.qid, qp->wq.rq.qid,
150 			      (int)qp->attr.state,
151 			      qp->wq.sq.flags & T4_SQ_ONCHIP);
152 	if (cc < space)
153 		qpd->pos += cc;
154 	return 0;
155 }
156 
157 static int qp_release(struct inode *inode, struct file *file)
158 {
159 	struct c4iw_debugfs_data *qpd = file->private_data;
160 	if (!qpd) {
161 		printk(KERN_INFO "%s null qpd?\n", __func__);
162 		return 0;
163 	}
164 	vfree(qpd->buf);
165 	kfree(qpd);
166 	return 0;
167 }
168 
169 static int qp_open(struct inode *inode, struct file *file)
170 {
171 	struct c4iw_debugfs_data *qpd;
172 	int ret = 0;
173 	int count = 1;
174 
175 	qpd = kmalloc(sizeof *qpd, GFP_KERNEL);
176 	if (!qpd) {
177 		ret = -ENOMEM;
178 		goto out;
179 	}
180 	qpd->devp = inode->i_private;
181 	qpd->pos = 0;
182 
183 	spin_lock_irq(&qpd->devp->lock);
184 	idr_for_each(&qpd->devp->qpidr, count_idrs, &count);
185 	spin_unlock_irq(&qpd->devp->lock);
186 
187 	qpd->bufsize = count * 128;
188 	qpd->buf = vmalloc(qpd->bufsize);
189 	if (!qpd->buf) {
190 		ret = -ENOMEM;
191 		goto err1;
192 	}
193 
194 	spin_lock_irq(&qpd->devp->lock);
195 	idr_for_each(&qpd->devp->qpidr, dump_qp, qpd);
196 	spin_unlock_irq(&qpd->devp->lock);
197 
198 	qpd->buf[qpd->pos++] = 0;
199 	file->private_data = qpd;
200 	goto out;
201 err1:
202 	kfree(qpd);
203 out:
204 	return ret;
205 }
206 
207 static const struct file_operations qp_debugfs_fops = {
208 	.owner   = THIS_MODULE,
209 	.open    = qp_open,
210 	.release = qp_release,
211 	.read    = debugfs_read,
212 	.llseek  = default_llseek,
213 };
214 
215 static int dump_stag(int id, void *p, void *data)
216 {
217 	struct c4iw_debugfs_data *stagd = data;
218 	int space;
219 	int cc;
220 
221 	space = stagd->bufsize - stagd->pos - 1;
222 	if (space == 0)
223 		return 1;
224 
225 	cc = snprintf(stagd->buf + stagd->pos, space, "0x%x\n", id<<8);
226 	if (cc < space)
227 		stagd->pos += cc;
228 	return 0;
229 }
230 
231 static int stag_release(struct inode *inode, struct file *file)
232 {
233 	struct c4iw_debugfs_data *stagd = file->private_data;
234 	if (!stagd) {
235 		printk(KERN_INFO "%s null stagd?\n", __func__);
236 		return 0;
237 	}
238 	kfree(stagd->buf);
239 	kfree(stagd);
240 	return 0;
241 }
242 
243 static int stag_open(struct inode *inode, struct file *file)
244 {
245 	struct c4iw_debugfs_data *stagd;
246 	int ret = 0;
247 	int count = 1;
248 
249 	stagd = kmalloc(sizeof *stagd, GFP_KERNEL);
250 	if (!stagd) {
251 		ret = -ENOMEM;
252 		goto out;
253 	}
254 	stagd->devp = inode->i_private;
255 	stagd->pos = 0;
256 
257 	spin_lock_irq(&stagd->devp->lock);
258 	idr_for_each(&stagd->devp->mmidr, count_idrs, &count);
259 	spin_unlock_irq(&stagd->devp->lock);
260 
261 	stagd->bufsize = count * sizeof("0x12345678\n");
262 	stagd->buf = kmalloc(stagd->bufsize, GFP_KERNEL);
263 	if (!stagd->buf) {
264 		ret = -ENOMEM;
265 		goto err1;
266 	}
267 
268 	spin_lock_irq(&stagd->devp->lock);
269 	idr_for_each(&stagd->devp->mmidr, dump_stag, stagd);
270 	spin_unlock_irq(&stagd->devp->lock);
271 
272 	stagd->buf[stagd->pos++] = 0;
273 	file->private_data = stagd;
274 	goto out;
275 err1:
276 	kfree(stagd);
277 out:
278 	return ret;
279 }
280 
281 static const struct file_operations stag_debugfs_fops = {
282 	.owner   = THIS_MODULE,
283 	.open    = stag_open,
284 	.release = stag_release,
285 	.read    = debugfs_read,
286 	.llseek  = default_llseek,
287 };
288 
289 static char *db_state_str[] = {"NORMAL", "FLOW_CONTROL", "RECOVERY", "STOPPED"};
290 
291 static int stats_show(struct seq_file *seq, void *v)
292 {
293 	struct c4iw_dev *dev = seq->private;
294 
295 	seq_printf(seq, "   Object: %10s %10s %10s %10s\n", "Total", "Current",
296 		   "Max", "Fail");
297 	seq_printf(seq, "     PDID: %10llu %10llu %10llu %10llu\n",
298 			dev->rdev.stats.pd.total, dev->rdev.stats.pd.cur,
299 			dev->rdev.stats.pd.max, dev->rdev.stats.pd.fail);
300 	seq_printf(seq, "      QID: %10llu %10llu %10llu %10llu\n",
301 			dev->rdev.stats.qid.total, dev->rdev.stats.qid.cur,
302 			dev->rdev.stats.qid.max, dev->rdev.stats.qid.fail);
303 	seq_printf(seq, "   TPTMEM: %10llu %10llu %10llu %10llu\n",
304 			dev->rdev.stats.stag.total, dev->rdev.stats.stag.cur,
305 			dev->rdev.stats.stag.max, dev->rdev.stats.stag.fail);
306 	seq_printf(seq, "   PBLMEM: %10llu %10llu %10llu %10llu\n",
307 			dev->rdev.stats.pbl.total, dev->rdev.stats.pbl.cur,
308 			dev->rdev.stats.pbl.max, dev->rdev.stats.pbl.fail);
309 	seq_printf(seq, "   RQTMEM: %10llu %10llu %10llu %10llu\n",
310 			dev->rdev.stats.rqt.total, dev->rdev.stats.rqt.cur,
311 			dev->rdev.stats.rqt.max, dev->rdev.stats.rqt.fail);
312 	seq_printf(seq, "  OCQPMEM: %10llu %10llu %10llu %10llu\n",
313 			dev->rdev.stats.ocqp.total, dev->rdev.stats.ocqp.cur,
314 			dev->rdev.stats.ocqp.max, dev->rdev.stats.ocqp.fail);
315 	seq_printf(seq, "  DB FULL: %10llu\n", dev->rdev.stats.db_full);
316 	seq_printf(seq, " DB EMPTY: %10llu\n", dev->rdev.stats.db_empty);
317 	seq_printf(seq, "  DB DROP: %10llu\n", dev->rdev.stats.db_drop);
318 	seq_printf(seq, " DB State: %s Transitions %llu FC Interruptions %llu\n",
319 		   db_state_str[dev->db_state],
320 		   dev->rdev.stats.db_state_transitions,
321 		   dev->rdev.stats.db_fc_interruptions);
322 	seq_printf(seq, "TCAM_FULL: %10llu\n", dev->rdev.stats.tcam_full);
323 	seq_printf(seq, "ACT_OFLD_CONN_FAILS: %10llu\n",
324 		   dev->rdev.stats.act_ofld_conn_fails);
325 	seq_printf(seq, "PAS_OFLD_CONN_FAILS: %10llu\n",
326 		   dev->rdev.stats.pas_ofld_conn_fails);
327 	return 0;
328 }
329 
330 static int stats_open(struct inode *inode, struct file *file)
331 {
332 	return single_open(file, stats_show, inode->i_private);
333 }
334 
335 static ssize_t stats_clear(struct file *file, const char __user *buf,
336 		size_t count, loff_t *pos)
337 {
338 	struct c4iw_dev *dev = ((struct seq_file *)file->private_data)->private;
339 
340 	mutex_lock(&dev->rdev.stats.lock);
341 	dev->rdev.stats.pd.max = 0;
342 	dev->rdev.stats.pd.fail = 0;
343 	dev->rdev.stats.qid.max = 0;
344 	dev->rdev.stats.qid.fail = 0;
345 	dev->rdev.stats.stag.max = 0;
346 	dev->rdev.stats.stag.fail = 0;
347 	dev->rdev.stats.pbl.max = 0;
348 	dev->rdev.stats.pbl.fail = 0;
349 	dev->rdev.stats.rqt.max = 0;
350 	dev->rdev.stats.rqt.fail = 0;
351 	dev->rdev.stats.ocqp.max = 0;
352 	dev->rdev.stats.ocqp.fail = 0;
353 	dev->rdev.stats.db_full = 0;
354 	dev->rdev.stats.db_empty = 0;
355 	dev->rdev.stats.db_drop = 0;
356 	dev->rdev.stats.db_state_transitions = 0;
357 	dev->rdev.stats.tcam_full = 0;
358 	dev->rdev.stats.act_ofld_conn_fails = 0;
359 	dev->rdev.stats.pas_ofld_conn_fails = 0;
360 	mutex_unlock(&dev->rdev.stats.lock);
361 	return count;
362 }
363 
364 static const struct file_operations stats_debugfs_fops = {
365 	.owner   = THIS_MODULE,
366 	.open    = stats_open,
367 	.release = single_release,
368 	.read    = seq_read,
369 	.llseek  = seq_lseek,
370 	.write   = stats_clear,
371 };
372 
373 static int dump_ep(int id, void *p, void *data)
374 {
375 	struct c4iw_ep *ep = p;
376 	struct c4iw_debugfs_data *epd = data;
377 	int space;
378 	int cc;
379 
380 	space = epd->bufsize - epd->pos - 1;
381 	if (space == 0)
382 		return 1;
383 
384 	if (ep->com.local_addr.ss_family == AF_INET) {
385 		struct sockaddr_in *lsin = (struct sockaddr_in *)
386 			&ep->com.local_addr;
387 		struct sockaddr_in *rsin = (struct sockaddr_in *)
388 			&ep->com.remote_addr;
389 
390 		cc = snprintf(epd->buf + epd->pos, space,
391 			      "ep %p cm_id %p qp %p state %d flags 0x%lx "
392 			      "history 0x%lx hwtid %d atid %d "
393 			      "%pI4:%d <-> %pI4:%d\n",
394 			      ep, ep->com.cm_id, ep->com.qp,
395 			      (int)ep->com.state, ep->com.flags,
396 			      ep->com.history, ep->hwtid, ep->atid,
397 			      &lsin->sin_addr, ntohs(lsin->sin_port),
398 			      &rsin->sin_addr, ntohs(rsin->sin_port));
399 	} else {
400 		struct sockaddr_in6 *lsin6 = (struct sockaddr_in6 *)
401 			&ep->com.local_addr;
402 		struct sockaddr_in6 *rsin6 = (struct sockaddr_in6 *)
403 			&ep->com.remote_addr;
404 
405 		cc = snprintf(epd->buf + epd->pos, space,
406 			      "ep %p cm_id %p qp %p state %d flags 0x%lx "
407 			      "history 0x%lx hwtid %d atid %d "
408 			      "%pI6:%d <-> %pI6:%d\n",
409 			      ep, ep->com.cm_id, ep->com.qp,
410 			      (int)ep->com.state, ep->com.flags,
411 			      ep->com.history, ep->hwtid, ep->atid,
412 			      &lsin6->sin6_addr, ntohs(lsin6->sin6_port),
413 			      &rsin6->sin6_addr, ntohs(rsin6->sin6_port));
414 	}
415 	if (cc < space)
416 		epd->pos += cc;
417 	return 0;
418 }
419 
420 static int dump_listen_ep(int id, void *p, void *data)
421 {
422 	struct c4iw_listen_ep *ep = p;
423 	struct c4iw_debugfs_data *epd = data;
424 	int space;
425 	int cc;
426 
427 	space = epd->bufsize - epd->pos - 1;
428 	if (space == 0)
429 		return 1;
430 
431 	if (ep->com.local_addr.ss_family == AF_INET) {
432 		struct sockaddr_in *lsin = (struct sockaddr_in *)
433 			&ep->com.local_addr;
434 
435 		cc = snprintf(epd->buf + epd->pos, space,
436 			      "ep %p cm_id %p state %d flags 0x%lx stid %d "
437 			      "backlog %d %pI4:%d\n",
438 			      ep, ep->com.cm_id, (int)ep->com.state,
439 			      ep->com.flags, ep->stid, ep->backlog,
440 			      &lsin->sin_addr, ntohs(lsin->sin_port));
441 	} else {
442 		struct sockaddr_in6 *lsin6 = (struct sockaddr_in6 *)
443 			&ep->com.local_addr;
444 
445 		cc = snprintf(epd->buf + epd->pos, space,
446 			      "ep %p cm_id %p state %d flags 0x%lx stid %d "
447 			      "backlog %d %pI6:%d\n",
448 			      ep, ep->com.cm_id, (int)ep->com.state,
449 			      ep->com.flags, ep->stid, ep->backlog,
450 			      &lsin6->sin6_addr, ntohs(lsin6->sin6_port));
451 	}
452 	if (cc < space)
453 		epd->pos += cc;
454 	return 0;
455 }
456 
457 static int ep_release(struct inode *inode, struct file *file)
458 {
459 	struct c4iw_debugfs_data *epd = file->private_data;
460 	if (!epd) {
461 		pr_info("%s null qpd?\n", __func__);
462 		return 0;
463 	}
464 	vfree(epd->buf);
465 	kfree(epd);
466 	return 0;
467 }
468 
469 static int ep_open(struct inode *inode, struct file *file)
470 {
471 	struct c4iw_debugfs_data *epd;
472 	int ret = 0;
473 	int count = 1;
474 
475 	epd = kmalloc(sizeof(*epd), GFP_KERNEL);
476 	if (!epd) {
477 		ret = -ENOMEM;
478 		goto out;
479 	}
480 	epd->devp = inode->i_private;
481 	epd->pos = 0;
482 
483 	spin_lock_irq(&epd->devp->lock);
484 	idr_for_each(&epd->devp->hwtid_idr, count_idrs, &count);
485 	idr_for_each(&epd->devp->atid_idr, count_idrs, &count);
486 	idr_for_each(&epd->devp->stid_idr, count_idrs, &count);
487 	spin_unlock_irq(&epd->devp->lock);
488 
489 	epd->bufsize = count * 160;
490 	epd->buf = vmalloc(epd->bufsize);
491 	if (!epd->buf) {
492 		ret = -ENOMEM;
493 		goto err1;
494 	}
495 
496 	spin_lock_irq(&epd->devp->lock);
497 	idr_for_each(&epd->devp->hwtid_idr, dump_ep, epd);
498 	idr_for_each(&epd->devp->atid_idr, dump_ep, epd);
499 	idr_for_each(&epd->devp->stid_idr, dump_listen_ep, epd);
500 	spin_unlock_irq(&epd->devp->lock);
501 
502 	file->private_data = epd;
503 	goto out;
504 err1:
505 	kfree(epd);
506 out:
507 	return ret;
508 }
509 
510 static const struct file_operations ep_debugfs_fops = {
511 	.owner   = THIS_MODULE,
512 	.open    = ep_open,
513 	.release = ep_release,
514 	.read    = debugfs_read,
515 };
516 
517 static int setup_debugfs(struct c4iw_dev *devp)
518 {
519 	struct dentry *de;
520 
521 	if (!devp->debugfs_root)
522 		return -1;
523 
524 	de = debugfs_create_file("qps", S_IWUSR, devp->debugfs_root,
525 				 (void *)devp, &qp_debugfs_fops);
526 	if (de && de->d_inode)
527 		de->d_inode->i_size = 4096;
528 
529 	de = debugfs_create_file("stags", S_IWUSR, devp->debugfs_root,
530 				 (void *)devp, &stag_debugfs_fops);
531 	if (de && de->d_inode)
532 		de->d_inode->i_size = 4096;
533 
534 	de = debugfs_create_file("stats", S_IWUSR, devp->debugfs_root,
535 			(void *)devp, &stats_debugfs_fops);
536 	if (de && de->d_inode)
537 		de->d_inode->i_size = 4096;
538 
539 	de = debugfs_create_file("eps", S_IWUSR, devp->debugfs_root,
540 			(void *)devp, &ep_debugfs_fops);
541 	if (de && de->d_inode)
542 		de->d_inode->i_size = 4096;
543 
544 	return 0;
545 }
546 
547 void c4iw_release_dev_ucontext(struct c4iw_rdev *rdev,
548 			       struct c4iw_dev_ucontext *uctx)
549 {
550 	struct list_head *pos, *nxt;
551 	struct c4iw_qid_list *entry;
552 
553 	mutex_lock(&uctx->lock);
554 	list_for_each_safe(pos, nxt, &uctx->qpids) {
555 		entry = list_entry(pos, struct c4iw_qid_list, entry);
556 		list_del_init(&entry->entry);
557 		if (!(entry->qid & rdev->qpmask)) {
558 			c4iw_put_resource(&rdev->resource.qid_table,
559 					  entry->qid);
560 			mutex_lock(&rdev->stats.lock);
561 			rdev->stats.qid.cur -= rdev->qpmask + 1;
562 			mutex_unlock(&rdev->stats.lock);
563 		}
564 		kfree(entry);
565 	}
566 
567 	list_for_each_safe(pos, nxt, &uctx->qpids) {
568 		entry = list_entry(pos, struct c4iw_qid_list, entry);
569 		list_del_init(&entry->entry);
570 		kfree(entry);
571 	}
572 	mutex_unlock(&uctx->lock);
573 }
574 
575 void c4iw_init_dev_ucontext(struct c4iw_rdev *rdev,
576 			    struct c4iw_dev_ucontext *uctx)
577 {
578 	INIT_LIST_HEAD(&uctx->qpids);
579 	INIT_LIST_HEAD(&uctx->cqids);
580 	mutex_init(&uctx->lock);
581 }
582 
583 /* Caller takes care of locking if needed */
584 static int c4iw_rdev_open(struct c4iw_rdev *rdev)
585 {
586 	int err;
587 
588 	c4iw_init_dev_ucontext(rdev, &rdev->uctx);
589 
590 	/*
591 	 * qpshift is the number of bits to shift the qpid left in order
592 	 * to get the correct address of the doorbell for that qp.
593 	 */
594 	rdev->qpshift = PAGE_SHIFT - ilog2(rdev->lldi.udb_density);
595 	rdev->qpmask = rdev->lldi.udb_density - 1;
596 	rdev->cqshift = PAGE_SHIFT - ilog2(rdev->lldi.ucq_density);
597 	rdev->cqmask = rdev->lldi.ucq_density - 1;
598 	PDBG("%s dev %s stag start 0x%0x size 0x%0x num stags %d "
599 	     "pbl start 0x%0x size 0x%0x rq start 0x%0x size 0x%0x "
600 	     "qp qid start %u size %u cq qid start %u size %u\n",
601 	     __func__, pci_name(rdev->lldi.pdev), rdev->lldi.vr->stag.start,
602 	     rdev->lldi.vr->stag.size, c4iw_num_stags(rdev),
603 	     rdev->lldi.vr->pbl.start,
604 	     rdev->lldi.vr->pbl.size, rdev->lldi.vr->rq.start,
605 	     rdev->lldi.vr->rq.size,
606 	     rdev->lldi.vr->qp.start,
607 	     rdev->lldi.vr->qp.size,
608 	     rdev->lldi.vr->cq.start,
609 	     rdev->lldi.vr->cq.size);
610 	PDBG("udb len 0x%x udb base %llx db_reg %p gts_reg %p qpshift %lu "
611 	     "qpmask 0x%x cqshift %lu cqmask 0x%x\n",
612 	     (unsigned)pci_resource_len(rdev->lldi.pdev, 2),
613 	     (u64)pci_resource_start(rdev->lldi.pdev, 2),
614 	     rdev->lldi.db_reg,
615 	     rdev->lldi.gts_reg,
616 	     rdev->qpshift, rdev->qpmask,
617 	     rdev->cqshift, rdev->cqmask);
618 
619 	if (c4iw_num_stags(rdev) == 0) {
620 		err = -EINVAL;
621 		goto err1;
622 	}
623 
624 	rdev->stats.pd.total = T4_MAX_NUM_PD;
625 	rdev->stats.stag.total = rdev->lldi.vr->stag.size;
626 	rdev->stats.pbl.total = rdev->lldi.vr->pbl.size;
627 	rdev->stats.rqt.total = rdev->lldi.vr->rq.size;
628 	rdev->stats.ocqp.total = rdev->lldi.vr->ocq.size;
629 	rdev->stats.qid.total = rdev->lldi.vr->qp.size;
630 
631 	err = c4iw_init_resource(rdev, c4iw_num_stags(rdev), T4_MAX_NUM_PD);
632 	if (err) {
633 		printk(KERN_ERR MOD "error %d initializing resources\n", err);
634 		goto err1;
635 	}
636 	err = c4iw_pblpool_create(rdev);
637 	if (err) {
638 		printk(KERN_ERR MOD "error %d initializing pbl pool\n", err);
639 		goto err2;
640 	}
641 	err = c4iw_rqtpool_create(rdev);
642 	if (err) {
643 		printk(KERN_ERR MOD "error %d initializing rqt pool\n", err);
644 		goto err3;
645 	}
646 	err = c4iw_ocqp_pool_create(rdev);
647 	if (err) {
648 		printk(KERN_ERR MOD "error %d initializing ocqp pool\n", err);
649 		goto err4;
650 	}
651 	rdev->status_page = (struct t4_dev_status_page *)
652 			    __get_free_page(GFP_KERNEL);
653 	if (!rdev->status_page) {
654 		pr_err(MOD "error allocating status page\n");
655 		goto err4;
656 	}
657 	return 0;
658 err4:
659 	c4iw_rqtpool_destroy(rdev);
660 err3:
661 	c4iw_pblpool_destroy(rdev);
662 err2:
663 	c4iw_destroy_resource(&rdev->resource);
664 err1:
665 	return err;
666 }
667 
668 static void c4iw_rdev_close(struct c4iw_rdev *rdev)
669 {
670 	free_page((unsigned long)rdev->status_page);
671 	c4iw_pblpool_destroy(rdev);
672 	c4iw_rqtpool_destroy(rdev);
673 	c4iw_destroy_resource(&rdev->resource);
674 }
675 
676 static void c4iw_dealloc(struct uld_ctx *ctx)
677 {
678 	c4iw_rdev_close(&ctx->dev->rdev);
679 	idr_destroy(&ctx->dev->cqidr);
680 	idr_destroy(&ctx->dev->qpidr);
681 	idr_destroy(&ctx->dev->mmidr);
682 	idr_destroy(&ctx->dev->hwtid_idr);
683 	idr_destroy(&ctx->dev->stid_idr);
684 	idr_destroy(&ctx->dev->atid_idr);
685 	if (ctx->dev->rdev.bar2_kva)
686 		iounmap(ctx->dev->rdev.bar2_kva);
687 	if (ctx->dev->rdev.oc_mw_kva)
688 		iounmap(ctx->dev->rdev.oc_mw_kva);
689 	ib_dealloc_device(&ctx->dev->ibdev);
690 	ctx->dev = NULL;
691 }
692 
693 static void c4iw_remove(struct uld_ctx *ctx)
694 {
695 	PDBG("%s c4iw_dev %p\n", __func__,  ctx->dev);
696 	c4iw_unregister_device(ctx->dev);
697 	c4iw_dealloc(ctx);
698 }
699 
700 static int rdma_supported(const struct cxgb4_lld_info *infop)
701 {
702 	return infop->vr->stag.size > 0 && infop->vr->pbl.size > 0 &&
703 	       infop->vr->rq.size > 0 && infop->vr->qp.size > 0 &&
704 	       infop->vr->cq.size > 0;
705 }
706 
707 static struct c4iw_dev *c4iw_alloc(const struct cxgb4_lld_info *infop)
708 {
709 	struct c4iw_dev *devp;
710 	int ret;
711 
712 	if (!rdma_supported(infop)) {
713 		printk(KERN_INFO MOD "%s: RDMA not supported on this device.\n",
714 		       pci_name(infop->pdev));
715 		return ERR_PTR(-ENOSYS);
716 	}
717 	if (!ocqp_supported(infop))
718 		pr_info("%s: On-Chip Queues not supported on this device.\n",
719 			pci_name(infop->pdev));
720 
721 	devp = (struct c4iw_dev *)ib_alloc_device(sizeof(*devp));
722 	if (!devp) {
723 		printk(KERN_ERR MOD "Cannot allocate ib device\n");
724 		return ERR_PTR(-ENOMEM);
725 	}
726 	devp->rdev.lldi = *infop;
727 
728 	/*
729 	 * For T5 devices, we map all of BAR2 with WC.
730 	 * For T4 devices with onchip qp mem, we map only that part
731 	 * of BAR2 with WC.
732 	 */
733 	devp->rdev.bar2_pa = pci_resource_start(devp->rdev.lldi.pdev, 2);
734 	if (is_t5(devp->rdev.lldi.adapter_type)) {
735 		devp->rdev.bar2_kva = ioremap_wc(devp->rdev.bar2_pa,
736 			pci_resource_len(devp->rdev.lldi.pdev, 2));
737 		if (!devp->rdev.bar2_kva) {
738 			pr_err(MOD "Unable to ioremap BAR2\n");
739 			return ERR_PTR(-EINVAL);
740 		}
741 	} else if (ocqp_supported(infop)) {
742 		devp->rdev.oc_mw_pa =
743 			pci_resource_start(devp->rdev.lldi.pdev, 2) +
744 			pci_resource_len(devp->rdev.lldi.pdev, 2) -
745 			roundup_pow_of_two(devp->rdev.lldi.vr->ocq.size);
746 		devp->rdev.oc_mw_kva = ioremap_wc(devp->rdev.oc_mw_pa,
747 			devp->rdev.lldi.vr->ocq.size);
748 		if (!devp->rdev.oc_mw_kva) {
749 			pr_err(MOD "Unable to ioremap onchip mem\n");
750 			return ERR_PTR(-EINVAL);
751 		}
752 	}
753 
754 	PDBG(KERN_INFO MOD "ocq memory: "
755 	       "hw_start 0x%x size %u mw_pa 0x%lx mw_kva %p\n",
756 	       devp->rdev.lldi.vr->ocq.start, devp->rdev.lldi.vr->ocq.size,
757 	       devp->rdev.oc_mw_pa, devp->rdev.oc_mw_kva);
758 
759 	ret = c4iw_rdev_open(&devp->rdev);
760 	if (ret) {
761 		printk(KERN_ERR MOD "Unable to open CXIO rdev err %d\n", ret);
762 		ib_dealloc_device(&devp->ibdev);
763 		return ERR_PTR(ret);
764 	}
765 
766 	idr_init(&devp->cqidr);
767 	idr_init(&devp->qpidr);
768 	idr_init(&devp->mmidr);
769 	idr_init(&devp->hwtid_idr);
770 	idr_init(&devp->stid_idr);
771 	idr_init(&devp->atid_idr);
772 	spin_lock_init(&devp->lock);
773 	mutex_init(&devp->rdev.stats.lock);
774 	mutex_init(&devp->db_mutex);
775 	INIT_LIST_HEAD(&devp->db_fc_list);
776 
777 	if (c4iw_debugfs_root) {
778 		devp->debugfs_root = debugfs_create_dir(
779 					pci_name(devp->rdev.lldi.pdev),
780 					c4iw_debugfs_root);
781 		setup_debugfs(devp);
782 	}
783 	return devp;
784 }
785 
786 static void *c4iw_uld_add(const struct cxgb4_lld_info *infop)
787 {
788 	struct uld_ctx *ctx;
789 	static int vers_printed;
790 	int i;
791 
792 	if (!vers_printed++)
793 		pr_info("Chelsio T4/T5 RDMA Driver - version %s\n",
794 			DRV_VERSION);
795 
796 	ctx = kzalloc(sizeof *ctx, GFP_KERNEL);
797 	if (!ctx) {
798 		ctx = ERR_PTR(-ENOMEM);
799 		goto out;
800 	}
801 	ctx->lldi = *infop;
802 
803 	PDBG("%s found device %s nchan %u nrxq %u ntxq %u nports %u\n",
804 	     __func__, pci_name(ctx->lldi.pdev),
805 	     ctx->lldi.nchan, ctx->lldi.nrxq,
806 	     ctx->lldi.ntxq, ctx->lldi.nports);
807 
808 	mutex_lock(&dev_mutex);
809 	list_add_tail(&ctx->entry, &uld_ctx_list);
810 	mutex_unlock(&dev_mutex);
811 
812 	for (i = 0; i < ctx->lldi.nrxq; i++)
813 		PDBG("rxqid[%u] %u\n", i, ctx->lldi.rxq_ids[i]);
814 out:
815 	return ctx;
816 }
817 
818 static inline struct sk_buff *copy_gl_to_skb_pkt(const struct pkt_gl *gl,
819 						 const __be64 *rsp,
820 						 u32 pktshift)
821 {
822 	struct sk_buff *skb;
823 
824 	/*
825 	 * Allocate space for cpl_pass_accept_req which will be synthesized by
826 	 * driver. Once the driver synthesizes the request the skb will go
827 	 * through the regular cpl_pass_accept_req processing.
828 	 * The math here assumes sizeof cpl_pass_accept_req >= sizeof
829 	 * cpl_rx_pkt.
830 	 */
831 	skb = alloc_skb(gl->tot_len + sizeof(struct cpl_pass_accept_req) +
832 			sizeof(struct rss_header) - pktshift, GFP_ATOMIC);
833 	if (unlikely(!skb))
834 		return NULL;
835 
836 	 __skb_put(skb, gl->tot_len + sizeof(struct cpl_pass_accept_req) +
837 		   sizeof(struct rss_header) - pktshift);
838 
839 	/*
840 	 * This skb will contain:
841 	 *   rss_header from the rspq descriptor (1 flit)
842 	 *   cpl_rx_pkt struct from the rspq descriptor (2 flits)
843 	 *   space for the difference between the size of an
844 	 *      rx_pkt and pass_accept_req cpl (1 flit)
845 	 *   the packet data from the gl
846 	 */
847 	skb_copy_to_linear_data(skb, rsp, sizeof(struct cpl_pass_accept_req) +
848 				sizeof(struct rss_header));
849 	skb_copy_to_linear_data_offset(skb, sizeof(struct rss_header) +
850 				       sizeof(struct cpl_pass_accept_req),
851 				       gl->va + pktshift,
852 				       gl->tot_len - pktshift);
853 	return skb;
854 }
855 
856 static inline int recv_rx_pkt(struct c4iw_dev *dev, const struct pkt_gl *gl,
857 			   const __be64 *rsp)
858 {
859 	unsigned int opcode = *(u8 *)rsp;
860 	struct sk_buff *skb;
861 
862 	if (opcode != CPL_RX_PKT)
863 		goto out;
864 
865 	skb = copy_gl_to_skb_pkt(gl , rsp, dev->rdev.lldi.sge_pktshift);
866 	if (skb == NULL)
867 		goto out;
868 
869 	if (c4iw_handlers[opcode] == NULL) {
870 		pr_info("%s no handler opcode 0x%x...\n", __func__,
871 		       opcode);
872 		kfree_skb(skb);
873 		goto out;
874 	}
875 	c4iw_handlers[opcode](dev, skb);
876 	return 1;
877 out:
878 	return 0;
879 }
880 
881 static int c4iw_uld_rx_handler(void *handle, const __be64 *rsp,
882 			const struct pkt_gl *gl)
883 {
884 	struct uld_ctx *ctx = handle;
885 	struct c4iw_dev *dev = ctx->dev;
886 	struct sk_buff *skb;
887 	u8 opcode;
888 
889 	if (gl == NULL) {
890 		/* omit RSS and rsp_ctrl at end of descriptor */
891 		unsigned int len = 64 - sizeof(struct rsp_ctrl) - 8;
892 
893 		skb = alloc_skb(256, GFP_ATOMIC);
894 		if (!skb)
895 			goto nomem;
896 		__skb_put(skb, len);
897 		skb_copy_to_linear_data(skb, &rsp[1], len);
898 	} else if (gl == CXGB4_MSG_AN) {
899 		const struct rsp_ctrl *rc = (void *)rsp;
900 
901 		u32 qid = be32_to_cpu(rc->pldbuflen_qid);
902 		c4iw_ev_handler(dev, qid);
903 		return 0;
904 	} else if (unlikely(*(u8 *)rsp != *(u8 *)gl->va)) {
905 		if (recv_rx_pkt(dev, gl, rsp))
906 			return 0;
907 
908 		pr_info("%s: unexpected FL contents at %p, " \
909 		       "RSS %#llx, FL %#llx, len %u\n",
910 		       pci_name(ctx->lldi.pdev), gl->va,
911 		       (unsigned long long)be64_to_cpu(*rsp),
912 		       (unsigned long long)be64_to_cpu(
913 		       *(__force __be64 *)gl->va),
914 		       gl->tot_len);
915 
916 		return 0;
917 	} else {
918 		skb = cxgb4_pktgl_to_skb(gl, 128, 128);
919 		if (unlikely(!skb))
920 			goto nomem;
921 	}
922 
923 	opcode = *(u8 *)rsp;
924 	if (c4iw_handlers[opcode]) {
925 		c4iw_handlers[opcode](dev, skb);
926 	} else {
927 		pr_info("%s no handler opcode 0x%x...\n", __func__,
928 		       opcode);
929 		kfree_skb(skb);
930 	}
931 
932 	return 0;
933 nomem:
934 	return -1;
935 }
936 
937 static int c4iw_uld_state_change(void *handle, enum cxgb4_state new_state)
938 {
939 	struct uld_ctx *ctx = handle;
940 
941 	PDBG("%s new_state %u\n", __func__, new_state);
942 	switch (new_state) {
943 	case CXGB4_STATE_UP:
944 		printk(KERN_INFO MOD "%s: Up\n", pci_name(ctx->lldi.pdev));
945 		if (!ctx->dev) {
946 			int ret;
947 
948 			ctx->dev = c4iw_alloc(&ctx->lldi);
949 			if (IS_ERR(ctx->dev)) {
950 				printk(KERN_ERR MOD
951 				       "%s: initialization failed: %ld\n",
952 				       pci_name(ctx->lldi.pdev),
953 				       PTR_ERR(ctx->dev));
954 				ctx->dev = NULL;
955 				break;
956 			}
957 			ret = c4iw_register_device(ctx->dev);
958 			if (ret) {
959 				printk(KERN_ERR MOD
960 				       "%s: RDMA registration failed: %d\n",
961 				       pci_name(ctx->lldi.pdev), ret);
962 				c4iw_dealloc(ctx);
963 			}
964 		}
965 		break;
966 	case CXGB4_STATE_DOWN:
967 		printk(KERN_INFO MOD "%s: Down\n",
968 		       pci_name(ctx->lldi.pdev));
969 		if (ctx->dev)
970 			c4iw_remove(ctx);
971 		break;
972 	case CXGB4_STATE_START_RECOVERY:
973 		printk(KERN_INFO MOD "%s: Fatal Error\n",
974 		       pci_name(ctx->lldi.pdev));
975 		if (ctx->dev) {
976 			struct ib_event event;
977 
978 			ctx->dev->rdev.flags |= T4_FATAL_ERROR;
979 			memset(&event, 0, sizeof event);
980 			event.event  = IB_EVENT_DEVICE_FATAL;
981 			event.device = &ctx->dev->ibdev;
982 			ib_dispatch_event(&event);
983 			c4iw_remove(ctx);
984 		}
985 		break;
986 	case CXGB4_STATE_DETACH:
987 		printk(KERN_INFO MOD "%s: Detach\n",
988 		       pci_name(ctx->lldi.pdev));
989 		if (ctx->dev)
990 			c4iw_remove(ctx);
991 		break;
992 	}
993 	return 0;
994 }
995 
996 static int disable_qp_db(int id, void *p, void *data)
997 {
998 	struct c4iw_qp *qp = p;
999 
1000 	t4_disable_wq_db(&qp->wq);
1001 	return 0;
1002 }
1003 
1004 static void stop_queues(struct uld_ctx *ctx)
1005 {
1006 	unsigned long flags;
1007 
1008 	spin_lock_irqsave(&ctx->dev->lock, flags);
1009 	ctx->dev->rdev.stats.db_state_transitions++;
1010 	ctx->dev->db_state = STOPPED;
1011 	if (ctx->dev->rdev.flags & T4_STATUS_PAGE_DISABLED)
1012 		idr_for_each(&ctx->dev->qpidr, disable_qp_db, NULL);
1013 	else
1014 		ctx->dev->rdev.status_page->db_off = 1;
1015 	spin_unlock_irqrestore(&ctx->dev->lock, flags);
1016 }
1017 
1018 static int enable_qp_db(int id, void *p, void *data)
1019 {
1020 	struct c4iw_qp *qp = p;
1021 
1022 	t4_enable_wq_db(&qp->wq);
1023 	return 0;
1024 }
1025 
1026 static void resume_rc_qp(struct c4iw_qp *qp)
1027 {
1028 	spin_lock(&qp->lock);
1029 	t4_ring_sq_db(&qp->wq, qp->wq.sq.wq_pidx_inc,
1030 		      is_t5(qp->rhp->rdev.lldi.adapter_type), NULL);
1031 	qp->wq.sq.wq_pidx_inc = 0;
1032 	t4_ring_rq_db(&qp->wq, qp->wq.rq.wq_pidx_inc,
1033 		      is_t5(qp->rhp->rdev.lldi.adapter_type), NULL);
1034 	qp->wq.rq.wq_pidx_inc = 0;
1035 	spin_unlock(&qp->lock);
1036 }
1037 
1038 static void resume_a_chunk(struct uld_ctx *ctx)
1039 {
1040 	int i;
1041 	struct c4iw_qp *qp;
1042 
1043 	for (i = 0; i < DB_FC_RESUME_SIZE; i++) {
1044 		qp = list_first_entry(&ctx->dev->db_fc_list, struct c4iw_qp,
1045 				      db_fc_entry);
1046 		list_del_init(&qp->db_fc_entry);
1047 		resume_rc_qp(qp);
1048 		if (list_empty(&ctx->dev->db_fc_list))
1049 			break;
1050 	}
1051 }
1052 
1053 static void resume_queues(struct uld_ctx *ctx)
1054 {
1055 	spin_lock_irq(&ctx->dev->lock);
1056 	if (ctx->dev->db_state != STOPPED)
1057 		goto out;
1058 	ctx->dev->db_state = FLOW_CONTROL;
1059 	while (1) {
1060 		if (list_empty(&ctx->dev->db_fc_list)) {
1061 			WARN_ON(ctx->dev->db_state != FLOW_CONTROL);
1062 			ctx->dev->db_state = NORMAL;
1063 			ctx->dev->rdev.stats.db_state_transitions++;
1064 			if (ctx->dev->rdev.flags & T4_STATUS_PAGE_DISABLED) {
1065 				idr_for_each(&ctx->dev->qpidr, enable_qp_db,
1066 					     NULL);
1067 			} else {
1068 				ctx->dev->rdev.status_page->db_off = 0;
1069 			}
1070 			break;
1071 		} else {
1072 			if (cxgb4_dbfifo_count(ctx->dev->rdev.lldi.ports[0], 1)
1073 			    < (ctx->dev->rdev.lldi.dbfifo_int_thresh <<
1074 			       DB_FC_DRAIN_THRESH)) {
1075 				resume_a_chunk(ctx);
1076 			}
1077 			if (!list_empty(&ctx->dev->db_fc_list)) {
1078 				spin_unlock_irq(&ctx->dev->lock);
1079 				if (DB_FC_RESUME_DELAY) {
1080 					set_current_state(TASK_UNINTERRUPTIBLE);
1081 					schedule_timeout(DB_FC_RESUME_DELAY);
1082 				}
1083 				spin_lock_irq(&ctx->dev->lock);
1084 				if (ctx->dev->db_state != FLOW_CONTROL)
1085 					break;
1086 			}
1087 		}
1088 	}
1089 out:
1090 	if (ctx->dev->db_state != NORMAL)
1091 		ctx->dev->rdev.stats.db_fc_interruptions++;
1092 	spin_unlock_irq(&ctx->dev->lock);
1093 }
1094 
1095 struct qp_list {
1096 	unsigned idx;
1097 	struct c4iw_qp **qps;
1098 };
1099 
1100 static int add_and_ref_qp(int id, void *p, void *data)
1101 {
1102 	struct qp_list *qp_listp = data;
1103 	struct c4iw_qp *qp = p;
1104 
1105 	c4iw_qp_add_ref(&qp->ibqp);
1106 	qp_listp->qps[qp_listp->idx++] = qp;
1107 	return 0;
1108 }
1109 
1110 static int count_qps(int id, void *p, void *data)
1111 {
1112 	unsigned *countp = data;
1113 	(*countp)++;
1114 	return 0;
1115 }
1116 
1117 static void deref_qps(struct qp_list *qp_list)
1118 {
1119 	int idx;
1120 
1121 	for (idx = 0; idx < qp_list->idx; idx++)
1122 		c4iw_qp_rem_ref(&qp_list->qps[idx]->ibqp);
1123 }
1124 
1125 static void recover_lost_dbs(struct uld_ctx *ctx, struct qp_list *qp_list)
1126 {
1127 	int idx;
1128 	int ret;
1129 
1130 	for (idx = 0; idx < qp_list->idx; idx++) {
1131 		struct c4iw_qp *qp = qp_list->qps[idx];
1132 
1133 		spin_lock_irq(&qp->rhp->lock);
1134 		spin_lock(&qp->lock);
1135 		ret = cxgb4_sync_txq_pidx(qp->rhp->rdev.lldi.ports[0],
1136 					  qp->wq.sq.qid,
1137 					  t4_sq_host_wq_pidx(&qp->wq),
1138 					  t4_sq_wq_size(&qp->wq));
1139 		if (ret) {
1140 			pr_err(KERN_ERR MOD "%s: Fatal error - "
1141 			       "DB overflow recovery failed - "
1142 			       "error syncing SQ qid %u\n",
1143 			       pci_name(ctx->lldi.pdev), qp->wq.sq.qid);
1144 			spin_unlock(&qp->lock);
1145 			spin_unlock_irq(&qp->rhp->lock);
1146 			return;
1147 		}
1148 		qp->wq.sq.wq_pidx_inc = 0;
1149 
1150 		ret = cxgb4_sync_txq_pidx(qp->rhp->rdev.lldi.ports[0],
1151 					  qp->wq.rq.qid,
1152 					  t4_rq_host_wq_pidx(&qp->wq),
1153 					  t4_rq_wq_size(&qp->wq));
1154 
1155 		if (ret) {
1156 			pr_err(KERN_ERR MOD "%s: Fatal error - "
1157 			       "DB overflow recovery failed - "
1158 			       "error syncing RQ qid %u\n",
1159 			       pci_name(ctx->lldi.pdev), qp->wq.rq.qid);
1160 			spin_unlock(&qp->lock);
1161 			spin_unlock_irq(&qp->rhp->lock);
1162 			return;
1163 		}
1164 		qp->wq.rq.wq_pidx_inc = 0;
1165 		spin_unlock(&qp->lock);
1166 		spin_unlock_irq(&qp->rhp->lock);
1167 
1168 		/* Wait for the dbfifo to drain */
1169 		while (cxgb4_dbfifo_count(qp->rhp->rdev.lldi.ports[0], 1) > 0) {
1170 			set_current_state(TASK_UNINTERRUPTIBLE);
1171 			schedule_timeout(usecs_to_jiffies(10));
1172 		}
1173 	}
1174 }
1175 
1176 static void recover_queues(struct uld_ctx *ctx)
1177 {
1178 	int count = 0;
1179 	struct qp_list qp_list;
1180 	int ret;
1181 
1182 	/* slow everybody down */
1183 	set_current_state(TASK_UNINTERRUPTIBLE);
1184 	schedule_timeout(usecs_to_jiffies(1000));
1185 
1186 	/* flush the SGE contexts */
1187 	ret = cxgb4_flush_eq_cache(ctx->dev->rdev.lldi.ports[0]);
1188 	if (ret) {
1189 		printk(KERN_ERR MOD "%s: Fatal error - DB overflow recovery failed\n",
1190 		       pci_name(ctx->lldi.pdev));
1191 		return;
1192 	}
1193 
1194 	/* Count active queues so we can build a list of queues to recover */
1195 	spin_lock_irq(&ctx->dev->lock);
1196 	WARN_ON(ctx->dev->db_state != STOPPED);
1197 	ctx->dev->db_state = RECOVERY;
1198 	idr_for_each(&ctx->dev->qpidr, count_qps, &count);
1199 
1200 	qp_list.qps = kzalloc(count * sizeof *qp_list.qps, GFP_ATOMIC);
1201 	if (!qp_list.qps) {
1202 		printk(KERN_ERR MOD "%s: Fatal error - DB overflow recovery failed\n",
1203 		       pci_name(ctx->lldi.pdev));
1204 		spin_unlock_irq(&ctx->dev->lock);
1205 		return;
1206 	}
1207 	qp_list.idx = 0;
1208 
1209 	/* add and ref each qp so it doesn't get freed */
1210 	idr_for_each(&ctx->dev->qpidr, add_and_ref_qp, &qp_list);
1211 
1212 	spin_unlock_irq(&ctx->dev->lock);
1213 
1214 	/* now traverse the list in a safe context to recover the db state*/
1215 	recover_lost_dbs(ctx, &qp_list);
1216 
1217 	/* we're almost done!  deref the qps and clean up */
1218 	deref_qps(&qp_list);
1219 	kfree(qp_list.qps);
1220 
1221 	spin_lock_irq(&ctx->dev->lock);
1222 	WARN_ON(ctx->dev->db_state != RECOVERY);
1223 	ctx->dev->db_state = STOPPED;
1224 	spin_unlock_irq(&ctx->dev->lock);
1225 }
1226 
1227 static int c4iw_uld_control(void *handle, enum cxgb4_control control, ...)
1228 {
1229 	struct uld_ctx *ctx = handle;
1230 
1231 	switch (control) {
1232 	case CXGB4_CONTROL_DB_FULL:
1233 		stop_queues(ctx);
1234 		ctx->dev->rdev.stats.db_full++;
1235 		break;
1236 	case CXGB4_CONTROL_DB_EMPTY:
1237 		resume_queues(ctx);
1238 		mutex_lock(&ctx->dev->rdev.stats.lock);
1239 		ctx->dev->rdev.stats.db_empty++;
1240 		mutex_unlock(&ctx->dev->rdev.stats.lock);
1241 		break;
1242 	case CXGB4_CONTROL_DB_DROP:
1243 		recover_queues(ctx);
1244 		mutex_lock(&ctx->dev->rdev.stats.lock);
1245 		ctx->dev->rdev.stats.db_drop++;
1246 		mutex_unlock(&ctx->dev->rdev.stats.lock);
1247 		break;
1248 	default:
1249 		printk(KERN_WARNING MOD "%s: unknown control cmd %u\n",
1250 		       pci_name(ctx->lldi.pdev), control);
1251 		break;
1252 	}
1253 	return 0;
1254 }
1255 
1256 static struct cxgb4_uld_info c4iw_uld_info = {
1257 	.name = DRV_NAME,
1258 	.add = c4iw_uld_add,
1259 	.rx_handler = c4iw_uld_rx_handler,
1260 	.state_change = c4iw_uld_state_change,
1261 	.control = c4iw_uld_control,
1262 };
1263 
1264 static int __init c4iw_init_module(void)
1265 {
1266 	int err;
1267 
1268 	err = c4iw_cm_init();
1269 	if (err)
1270 		return err;
1271 
1272 	c4iw_debugfs_root = debugfs_create_dir(DRV_NAME, NULL);
1273 	if (!c4iw_debugfs_root)
1274 		printk(KERN_WARNING MOD
1275 		       "could not create debugfs entry, continuing\n");
1276 
1277 	cxgb4_register_uld(CXGB4_ULD_RDMA, &c4iw_uld_info);
1278 
1279 	return 0;
1280 }
1281 
1282 static void __exit c4iw_exit_module(void)
1283 {
1284 	struct uld_ctx *ctx, *tmp;
1285 
1286 	mutex_lock(&dev_mutex);
1287 	list_for_each_entry_safe(ctx, tmp, &uld_ctx_list, entry) {
1288 		if (ctx->dev)
1289 			c4iw_remove(ctx);
1290 		kfree(ctx);
1291 	}
1292 	mutex_unlock(&dev_mutex);
1293 	cxgb4_unregister_uld(CXGB4_ULD_RDMA);
1294 	c4iw_cm_term();
1295 	debugfs_remove_recursive(c4iw_debugfs_root);
1296 }
1297 
1298 module_init(c4iw_init_module);
1299 module_exit(c4iw_exit_module);
1300