xref: /openbmc/linux/drivers/infiniband/hw/mlx4/cm.c (revision 711aab1d)
1 /*
2  * Copyright (c) 2012 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_mad.h>
34 
35 #include <linux/mlx4/cmd.h>
36 #include <linux/rbtree.h>
37 #include <linux/idr.h>
38 #include <rdma/ib_cm.h>
39 
40 #include "mlx4_ib.h"
41 
42 #define CM_CLEANUP_CACHE_TIMEOUT  (5 * HZ)
43 
44 struct id_map_entry {
45 	struct rb_node node;
46 
47 	u32 sl_cm_id;
48 	u32 pv_cm_id;
49 	int slave_id;
50 	int scheduled_delete;
51 	struct mlx4_ib_dev *dev;
52 
53 	struct list_head list;
54 	struct delayed_work timeout;
55 };
56 
57 struct cm_generic_msg {
58 	struct ib_mad_hdr hdr;
59 
60 	__be32 local_comm_id;
61 	__be32 remote_comm_id;
62 };
63 
64 struct cm_sidr_generic_msg {
65 	struct ib_mad_hdr hdr;
66 	__be32 request_id;
67 };
68 
69 struct cm_req_msg {
70 	unsigned char unused[0x60];
71 	union ib_gid primary_path_sgid;
72 };
73 
74 
75 static void set_local_comm_id(struct ib_mad *mad, u32 cm_id)
76 {
77 	if (mad->mad_hdr.attr_id == CM_SIDR_REQ_ATTR_ID) {
78 		struct cm_sidr_generic_msg *msg =
79 			(struct cm_sidr_generic_msg *)mad;
80 		msg->request_id = cpu_to_be32(cm_id);
81 	} else if (mad->mad_hdr.attr_id == CM_SIDR_REP_ATTR_ID) {
82 		pr_err("trying to set local_comm_id in SIDR_REP\n");
83 		return;
84 	} else {
85 		struct cm_generic_msg *msg = (struct cm_generic_msg *)mad;
86 		msg->local_comm_id = cpu_to_be32(cm_id);
87 	}
88 }
89 
90 static u32 get_local_comm_id(struct ib_mad *mad)
91 {
92 	if (mad->mad_hdr.attr_id == CM_SIDR_REQ_ATTR_ID) {
93 		struct cm_sidr_generic_msg *msg =
94 			(struct cm_sidr_generic_msg *)mad;
95 		return be32_to_cpu(msg->request_id);
96 	} else if (mad->mad_hdr.attr_id == CM_SIDR_REP_ATTR_ID) {
97 		pr_err("trying to set local_comm_id in SIDR_REP\n");
98 		return -1;
99 	} else {
100 		struct cm_generic_msg *msg = (struct cm_generic_msg *)mad;
101 		return be32_to_cpu(msg->local_comm_id);
102 	}
103 }
104 
105 static void set_remote_comm_id(struct ib_mad *mad, u32 cm_id)
106 {
107 	if (mad->mad_hdr.attr_id == CM_SIDR_REP_ATTR_ID) {
108 		struct cm_sidr_generic_msg *msg =
109 			(struct cm_sidr_generic_msg *)mad;
110 		msg->request_id = cpu_to_be32(cm_id);
111 	} else if (mad->mad_hdr.attr_id == CM_SIDR_REQ_ATTR_ID) {
112 		pr_err("trying to set remote_comm_id in SIDR_REQ\n");
113 		return;
114 	} else {
115 		struct cm_generic_msg *msg = (struct cm_generic_msg *)mad;
116 		msg->remote_comm_id = cpu_to_be32(cm_id);
117 	}
118 }
119 
120 static u32 get_remote_comm_id(struct ib_mad *mad)
121 {
122 	if (mad->mad_hdr.attr_id == CM_SIDR_REP_ATTR_ID) {
123 		struct cm_sidr_generic_msg *msg =
124 			(struct cm_sidr_generic_msg *)mad;
125 		return be32_to_cpu(msg->request_id);
126 	} else if (mad->mad_hdr.attr_id == CM_SIDR_REQ_ATTR_ID) {
127 		pr_err("trying to set remote_comm_id in SIDR_REQ\n");
128 		return -1;
129 	} else {
130 		struct cm_generic_msg *msg = (struct cm_generic_msg *)mad;
131 		return be32_to_cpu(msg->remote_comm_id);
132 	}
133 }
134 
135 static union ib_gid gid_from_req_msg(struct ib_device *ibdev, struct ib_mad *mad)
136 {
137 	struct cm_req_msg *msg = (struct cm_req_msg *)mad;
138 
139 	return msg->primary_path_sgid;
140 }
141 
142 /* Lock should be taken before called */
143 static struct id_map_entry *
144 id_map_find_by_sl_id(struct ib_device *ibdev, u32 slave_id, u32 sl_cm_id)
145 {
146 	struct rb_root *sl_id_map = &to_mdev(ibdev)->sriov.sl_id_map;
147 	struct rb_node *node = sl_id_map->rb_node;
148 
149 	while (node) {
150 		struct id_map_entry *id_map_entry =
151 			rb_entry(node, struct id_map_entry, node);
152 
153 		if (id_map_entry->sl_cm_id > sl_cm_id)
154 			node = node->rb_left;
155 		else if (id_map_entry->sl_cm_id < sl_cm_id)
156 			node = node->rb_right;
157 		else if (id_map_entry->slave_id > slave_id)
158 			node = node->rb_left;
159 		else if (id_map_entry->slave_id < slave_id)
160 			node = node->rb_right;
161 		else
162 			return id_map_entry;
163 	}
164 	return NULL;
165 }
166 
167 static void id_map_ent_timeout(struct work_struct *work)
168 {
169 	struct delayed_work *delay = to_delayed_work(work);
170 	struct id_map_entry *ent = container_of(delay, struct id_map_entry, timeout);
171 	struct id_map_entry *db_ent, *found_ent;
172 	struct mlx4_ib_dev *dev = ent->dev;
173 	struct mlx4_ib_sriov *sriov = &dev->sriov;
174 	struct rb_root *sl_id_map = &sriov->sl_id_map;
175 	int pv_id = (int) ent->pv_cm_id;
176 
177 	spin_lock(&sriov->id_map_lock);
178 	db_ent = (struct id_map_entry *)idr_find(&sriov->pv_id_table, pv_id);
179 	if (!db_ent)
180 		goto out;
181 	found_ent = id_map_find_by_sl_id(&dev->ib_dev, ent->slave_id, ent->sl_cm_id);
182 	if (found_ent && found_ent == ent)
183 		rb_erase(&found_ent->node, sl_id_map);
184 	idr_remove(&sriov->pv_id_table, pv_id);
185 
186 out:
187 	list_del(&ent->list);
188 	spin_unlock(&sriov->id_map_lock);
189 	kfree(ent);
190 }
191 
192 static void id_map_find_del(struct ib_device *ibdev, int pv_cm_id)
193 {
194 	struct mlx4_ib_sriov *sriov = &to_mdev(ibdev)->sriov;
195 	struct rb_root *sl_id_map = &sriov->sl_id_map;
196 	struct id_map_entry *ent, *found_ent;
197 
198 	spin_lock(&sriov->id_map_lock);
199 	ent = (struct id_map_entry *)idr_find(&sriov->pv_id_table, pv_cm_id);
200 	if (!ent)
201 		goto out;
202 	found_ent = id_map_find_by_sl_id(ibdev, ent->slave_id, ent->sl_cm_id);
203 	if (found_ent && found_ent == ent)
204 		rb_erase(&found_ent->node, sl_id_map);
205 	idr_remove(&sriov->pv_id_table, pv_cm_id);
206 out:
207 	spin_unlock(&sriov->id_map_lock);
208 }
209 
210 static void sl_id_map_add(struct ib_device *ibdev, struct id_map_entry *new)
211 {
212 	struct rb_root *sl_id_map = &to_mdev(ibdev)->sriov.sl_id_map;
213 	struct rb_node **link = &sl_id_map->rb_node, *parent = NULL;
214 	struct id_map_entry *ent;
215 	int slave_id = new->slave_id;
216 	int sl_cm_id = new->sl_cm_id;
217 
218 	ent = id_map_find_by_sl_id(ibdev, slave_id, sl_cm_id);
219 	if (ent) {
220 		pr_debug("overriding existing sl_id_map entry (cm_id = %x)\n",
221 			 sl_cm_id);
222 
223 		rb_replace_node(&ent->node, &new->node, sl_id_map);
224 		return;
225 	}
226 
227 	/* Go to the bottom of the tree */
228 	while (*link) {
229 		parent = *link;
230 		ent = rb_entry(parent, struct id_map_entry, node);
231 
232 		if (ent->sl_cm_id > sl_cm_id || (ent->sl_cm_id == sl_cm_id && ent->slave_id > slave_id))
233 			link = &(*link)->rb_left;
234 		else
235 			link = &(*link)->rb_right;
236 	}
237 
238 	rb_link_node(&new->node, parent, link);
239 	rb_insert_color(&new->node, sl_id_map);
240 }
241 
242 static struct id_map_entry *
243 id_map_alloc(struct ib_device *ibdev, int slave_id, u32 sl_cm_id)
244 {
245 	int ret;
246 	struct id_map_entry *ent;
247 	struct mlx4_ib_sriov *sriov = &to_mdev(ibdev)->sriov;
248 
249 	ent = kmalloc(sizeof (struct id_map_entry), GFP_KERNEL);
250 	if (!ent)
251 		return ERR_PTR(-ENOMEM);
252 
253 	ent->sl_cm_id = sl_cm_id;
254 	ent->slave_id = slave_id;
255 	ent->scheduled_delete = 0;
256 	ent->dev = to_mdev(ibdev);
257 	INIT_DELAYED_WORK(&ent->timeout, id_map_ent_timeout);
258 
259 	idr_preload(GFP_KERNEL);
260 	spin_lock(&to_mdev(ibdev)->sriov.id_map_lock);
261 
262 	ret = idr_alloc_cyclic(&sriov->pv_id_table, ent, 0, 0, GFP_NOWAIT);
263 	if (ret >= 0) {
264 		ent->pv_cm_id = (u32)ret;
265 		sl_id_map_add(ibdev, ent);
266 		list_add_tail(&ent->list, &sriov->cm_list);
267 	}
268 
269 	spin_unlock(&sriov->id_map_lock);
270 	idr_preload_end();
271 
272 	if (ret >= 0)
273 		return ent;
274 
275 	/*error flow*/
276 	kfree(ent);
277 	mlx4_ib_warn(ibdev, "No more space in the idr (err:0x%x)\n", ret);
278 	return ERR_PTR(-ENOMEM);
279 }
280 
281 static struct id_map_entry *
282 id_map_get(struct ib_device *ibdev, int *pv_cm_id, int slave_id, int sl_cm_id)
283 {
284 	struct id_map_entry *ent;
285 	struct mlx4_ib_sriov *sriov = &to_mdev(ibdev)->sriov;
286 
287 	spin_lock(&sriov->id_map_lock);
288 	if (*pv_cm_id == -1) {
289 		ent = id_map_find_by_sl_id(ibdev, slave_id, sl_cm_id);
290 		if (ent)
291 			*pv_cm_id = (int) ent->pv_cm_id;
292 	} else
293 		ent = (struct id_map_entry *)idr_find(&sriov->pv_id_table, *pv_cm_id);
294 	spin_unlock(&sriov->id_map_lock);
295 
296 	return ent;
297 }
298 
299 static void schedule_delayed(struct ib_device *ibdev, struct id_map_entry *id)
300 {
301 	struct mlx4_ib_sriov *sriov = &to_mdev(ibdev)->sriov;
302 	unsigned long flags;
303 
304 	spin_lock(&sriov->id_map_lock);
305 	spin_lock_irqsave(&sriov->going_down_lock, flags);
306 	/*make sure that there is no schedule inside the scheduled work.*/
307 	if (!sriov->is_going_down) {
308 		id->scheduled_delete = 1;
309 		schedule_delayed_work(&id->timeout, CM_CLEANUP_CACHE_TIMEOUT);
310 	}
311 	spin_unlock_irqrestore(&sriov->going_down_lock, flags);
312 	spin_unlock(&sriov->id_map_lock);
313 }
314 
315 int mlx4_ib_multiplex_cm_handler(struct ib_device *ibdev, int port, int slave_id,
316 		struct ib_mad *mad)
317 {
318 	struct id_map_entry *id;
319 	u32 sl_cm_id;
320 	int pv_cm_id = -1;
321 
322 	if (mad->mad_hdr.attr_id == CM_REQ_ATTR_ID ||
323 			mad->mad_hdr.attr_id == CM_REP_ATTR_ID ||
324 			mad->mad_hdr.attr_id == CM_SIDR_REQ_ATTR_ID) {
325 		sl_cm_id = get_local_comm_id(mad);
326 		id = id_map_get(ibdev, &pv_cm_id, slave_id, sl_cm_id);
327 		if (id)
328 			goto cont;
329 		id = id_map_alloc(ibdev, slave_id, sl_cm_id);
330 		if (IS_ERR(id)) {
331 			mlx4_ib_warn(ibdev, "%s: id{slave: %d, sl_cm_id: 0x%x} Failed to id_map_alloc\n",
332 				__func__, slave_id, sl_cm_id);
333 			return PTR_ERR(id);
334 		}
335 	} else if (mad->mad_hdr.attr_id == CM_REJ_ATTR_ID ||
336 		   mad->mad_hdr.attr_id == CM_SIDR_REP_ATTR_ID) {
337 		return 0;
338 	} else {
339 		sl_cm_id = get_local_comm_id(mad);
340 		id = id_map_get(ibdev, &pv_cm_id, slave_id, sl_cm_id);
341 	}
342 
343 	if (!id) {
344 		pr_debug("id{slave: %d, sl_cm_id: 0x%x} is NULL!\n",
345 			 slave_id, sl_cm_id);
346 		return -EINVAL;
347 	}
348 
349 cont:
350 	set_local_comm_id(mad, id->pv_cm_id);
351 
352 	if (mad->mad_hdr.attr_id == CM_DREQ_ATTR_ID)
353 		schedule_delayed(ibdev, id);
354 	else if (mad->mad_hdr.attr_id == CM_DREP_ATTR_ID)
355 		id_map_find_del(ibdev, pv_cm_id);
356 
357 	return 0;
358 }
359 
360 int mlx4_ib_demux_cm_handler(struct ib_device *ibdev, int port, int *slave,
361 			     struct ib_mad *mad)
362 {
363 	u32 pv_cm_id;
364 	struct id_map_entry *id;
365 
366 	if (mad->mad_hdr.attr_id == CM_REQ_ATTR_ID ||
367 	    mad->mad_hdr.attr_id == CM_SIDR_REQ_ATTR_ID) {
368 		union ib_gid gid;
369 
370 		if (!slave)
371 			return 0;
372 
373 		gid = gid_from_req_msg(ibdev, mad);
374 		*slave = mlx4_ib_find_real_gid(ibdev, port, gid.global.interface_id);
375 		if (*slave < 0) {
376 			mlx4_ib_warn(ibdev, "failed matching slave_id by gid (0x%llx)\n",
377 				     be64_to_cpu(gid.global.interface_id));
378 			return -ENOENT;
379 		}
380 		return 0;
381 	}
382 
383 	pv_cm_id = get_remote_comm_id(mad);
384 	id = id_map_get(ibdev, (int *)&pv_cm_id, -1, -1);
385 
386 	if (!id) {
387 		pr_debug("Couldn't find an entry for pv_cm_id 0x%x\n", pv_cm_id);
388 		return -ENOENT;
389 	}
390 
391 	if (slave)
392 		*slave = id->slave_id;
393 	set_remote_comm_id(mad, id->sl_cm_id);
394 
395 	if (mad->mad_hdr.attr_id == CM_DREQ_ATTR_ID)
396 		schedule_delayed(ibdev, id);
397 	else if (mad->mad_hdr.attr_id == CM_REJ_ATTR_ID ||
398 			mad->mad_hdr.attr_id == CM_DREP_ATTR_ID) {
399 		id_map_find_del(ibdev, (int) pv_cm_id);
400 	}
401 
402 	return 0;
403 }
404 
405 void mlx4_ib_cm_paravirt_init(struct mlx4_ib_dev *dev)
406 {
407 	spin_lock_init(&dev->sriov.id_map_lock);
408 	INIT_LIST_HEAD(&dev->sriov.cm_list);
409 	dev->sriov.sl_id_map = RB_ROOT;
410 	idr_init(&dev->sriov.pv_id_table);
411 }
412 
413 /* slave = -1 ==> all slaves */
414 /* TBD -- call paravirt clean for single slave.  Need for slave RESET event */
415 void mlx4_ib_cm_paravirt_clean(struct mlx4_ib_dev *dev, int slave)
416 {
417 	struct mlx4_ib_sriov *sriov = &dev->sriov;
418 	struct rb_root *sl_id_map = &sriov->sl_id_map;
419 	struct list_head lh;
420 	struct rb_node *nd;
421 	int need_flush = 0;
422 	struct id_map_entry *map, *tmp_map;
423 	/* cancel all delayed work queue entries */
424 	INIT_LIST_HEAD(&lh);
425 	spin_lock(&sriov->id_map_lock);
426 	list_for_each_entry_safe(map, tmp_map, &dev->sriov.cm_list, list) {
427 		if (slave < 0 || slave == map->slave_id) {
428 			if (map->scheduled_delete)
429 				need_flush |= !cancel_delayed_work(&map->timeout);
430 		}
431 	}
432 
433 	spin_unlock(&sriov->id_map_lock);
434 
435 	if (need_flush)
436 		flush_scheduled_work(); /* make sure all timers were flushed */
437 
438 	/* now, remove all leftover entries from databases*/
439 	spin_lock(&sriov->id_map_lock);
440 	if (slave < 0) {
441 		while (rb_first(sl_id_map)) {
442 			struct id_map_entry *ent =
443 				rb_entry(rb_first(sl_id_map),
444 					 struct id_map_entry, node);
445 
446 			rb_erase(&ent->node, sl_id_map);
447 			idr_remove(&sriov->pv_id_table, (int) ent->pv_cm_id);
448 		}
449 		list_splice_init(&dev->sriov.cm_list, &lh);
450 	} else {
451 		/* first, move nodes belonging to slave to db remove list */
452 		nd = rb_first(sl_id_map);
453 		while (nd) {
454 			struct id_map_entry *ent =
455 				rb_entry(nd, struct id_map_entry, node);
456 			nd = rb_next(nd);
457 			if (ent->slave_id == slave)
458 				list_move_tail(&ent->list, &lh);
459 		}
460 		/* remove those nodes from databases */
461 		list_for_each_entry_safe(map, tmp_map, &lh, list) {
462 			rb_erase(&map->node, sl_id_map);
463 			idr_remove(&sriov->pv_id_table, (int) map->pv_cm_id);
464 		}
465 
466 		/* add remaining nodes from cm_list */
467 		list_for_each_entry_safe(map, tmp_map, &dev->sriov.cm_list, list) {
468 			if (slave == map->slave_id)
469 				list_move_tail(&map->list, &lh);
470 		}
471 	}
472 
473 	spin_unlock(&sriov->id_map_lock);
474 
475 	/* free any map entries left behind due to cancel_delayed_work above */
476 	list_for_each_entry_safe(map, tmp_map, &lh, list) {
477 		list_del(&map->list);
478 		kfree(map);
479 	}
480 }
481