xref: /openbmc/linux/drivers/infiniband/hw/mlx4/cm.c (revision dc6a81c3)
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  (30 * 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 *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 
176 	spin_lock(&sriov->id_map_lock);
177 	if (!xa_erase(&sriov->pv_id_table, ent->pv_cm_id))
178 		goto out;
179 	found_ent = id_map_find_by_sl_id(&dev->ib_dev, ent->slave_id, ent->sl_cm_id);
180 	if (found_ent && found_ent == ent)
181 		rb_erase(&found_ent->node, sl_id_map);
182 
183 out:
184 	list_del(&ent->list);
185 	spin_unlock(&sriov->id_map_lock);
186 	kfree(ent);
187 }
188 
189 static void sl_id_map_add(struct ib_device *ibdev, struct id_map_entry *new)
190 {
191 	struct rb_root *sl_id_map = &to_mdev(ibdev)->sriov.sl_id_map;
192 	struct rb_node **link = &sl_id_map->rb_node, *parent = NULL;
193 	struct id_map_entry *ent;
194 	int slave_id = new->slave_id;
195 	int sl_cm_id = new->sl_cm_id;
196 
197 	ent = id_map_find_by_sl_id(ibdev, slave_id, sl_cm_id);
198 	if (ent) {
199 		pr_debug("overriding existing sl_id_map entry (cm_id = %x)\n",
200 			 sl_cm_id);
201 
202 		rb_replace_node(&ent->node, &new->node, sl_id_map);
203 		return;
204 	}
205 
206 	/* Go to the bottom of the tree */
207 	while (*link) {
208 		parent = *link;
209 		ent = rb_entry(parent, struct id_map_entry, node);
210 
211 		if (ent->sl_cm_id > sl_cm_id || (ent->sl_cm_id == sl_cm_id && ent->slave_id > slave_id))
212 			link = &(*link)->rb_left;
213 		else
214 			link = &(*link)->rb_right;
215 	}
216 
217 	rb_link_node(&new->node, parent, link);
218 	rb_insert_color(&new->node, sl_id_map);
219 }
220 
221 static struct id_map_entry *
222 id_map_alloc(struct ib_device *ibdev, int slave_id, u32 sl_cm_id)
223 {
224 	int ret;
225 	struct id_map_entry *ent;
226 	struct mlx4_ib_sriov *sriov = &to_mdev(ibdev)->sriov;
227 
228 	ent = kmalloc(sizeof (struct id_map_entry), GFP_KERNEL);
229 	if (!ent)
230 		return ERR_PTR(-ENOMEM);
231 
232 	ent->sl_cm_id = sl_cm_id;
233 	ent->slave_id = slave_id;
234 	ent->scheduled_delete = 0;
235 	ent->dev = to_mdev(ibdev);
236 	INIT_DELAYED_WORK(&ent->timeout, id_map_ent_timeout);
237 
238 	ret = xa_alloc_cyclic(&sriov->pv_id_table, &ent->pv_cm_id, ent,
239 			xa_limit_32b, &sriov->pv_id_next, GFP_KERNEL);
240 	if (ret >= 0) {
241 		spin_lock(&sriov->id_map_lock);
242 		sl_id_map_add(ibdev, ent);
243 		list_add_tail(&ent->list, &sriov->cm_list);
244 		spin_unlock(&sriov->id_map_lock);
245 		return ent;
246 	}
247 
248 	/*error flow*/
249 	kfree(ent);
250 	mlx4_ib_warn(ibdev, "Allocation failed (err:0x%x)\n", ret);
251 	return ERR_PTR(-ENOMEM);
252 }
253 
254 static struct id_map_entry *
255 id_map_get(struct ib_device *ibdev, int *pv_cm_id, int slave_id, int sl_cm_id)
256 {
257 	struct id_map_entry *ent;
258 	struct mlx4_ib_sriov *sriov = &to_mdev(ibdev)->sriov;
259 
260 	spin_lock(&sriov->id_map_lock);
261 	if (*pv_cm_id == -1) {
262 		ent = id_map_find_by_sl_id(ibdev, slave_id, sl_cm_id);
263 		if (ent)
264 			*pv_cm_id = (int) ent->pv_cm_id;
265 	} else
266 		ent = xa_load(&sriov->pv_id_table, *pv_cm_id);
267 	spin_unlock(&sriov->id_map_lock);
268 
269 	return ent;
270 }
271 
272 static void schedule_delayed(struct ib_device *ibdev, struct id_map_entry *id)
273 {
274 	struct mlx4_ib_sriov *sriov = &to_mdev(ibdev)->sriov;
275 	unsigned long flags;
276 
277 	spin_lock(&sriov->id_map_lock);
278 	spin_lock_irqsave(&sriov->going_down_lock, flags);
279 	/*make sure that there is no schedule inside the scheduled work.*/
280 	if (!sriov->is_going_down && !id->scheduled_delete) {
281 		id->scheduled_delete = 1;
282 		schedule_delayed_work(&id->timeout, CM_CLEANUP_CACHE_TIMEOUT);
283 	}
284 	spin_unlock_irqrestore(&sriov->going_down_lock, flags);
285 	spin_unlock(&sriov->id_map_lock);
286 }
287 
288 int mlx4_ib_multiplex_cm_handler(struct ib_device *ibdev, int port, int slave_id,
289 		struct ib_mad *mad)
290 {
291 	struct id_map_entry *id;
292 	u32 sl_cm_id;
293 	int pv_cm_id = -1;
294 
295 	if (mad->mad_hdr.attr_id == CM_REQ_ATTR_ID ||
296 			mad->mad_hdr.attr_id == CM_REP_ATTR_ID ||
297 			mad->mad_hdr.attr_id == CM_SIDR_REQ_ATTR_ID) {
298 		sl_cm_id = get_local_comm_id(mad);
299 		id = id_map_get(ibdev, &pv_cm_id, slave_id, sl_cm_id);
300 		if (id)
301 			goto cont;
302 		id = id_map_alloc(ibdev, slave_id, sl_cm_id);
303 		if (IS_ERR(id)) {
304 			mlx4_ib_warn(ibdev, "%s: id{slave: %d, sl_cm_id: 0x%x} Failed to id_map_alloc\n",
305 				__func__, slave_id, sl_cm_id);
306 			return PTR_ERR(id);
307 		}
308 	} else if (mad->mad_hdr.attr_id == CM_REJ_ATTR_ID ||
309 		   mad->mad_hdr.attr_id == CM_SIDR_REP_ATTR_ID) {
310 		return 0;
311 	} else {
312 		sl_cm_id = get_local_comm_id(mad);
313 		id = id_map_get(ibdev, &pv_cm_id, slave_id, sl_cm_id);
314 	}
315 
316 	if (!id) {
317 		pr_debug("id{slave: %d, sl_cm_id: 0x%x} is NULL!\n",
318 			 slave_id, sl_cm_id);
319 		return -EINVAL;
320 	}
321 
322 cont:
323 	set_local_comm_id(mad, id->pv_cm_id);
324 
325 	if (mad->mad_hdr.attr_id == CM_DREQ_ATTR_ID)
326 		schedule_delayed(ibdev, id);
327 	return 0;
328 }
329 
330 int mlx4_ib_demux_cm_handler(struct ib_device *ibdev, int port, int *slave,
331 			     struct ib_mad *mad)
332 {
333 	u32 pv_cm_id;
334 	struct id_map_entry *id;
335 
336 	if (mad->mad_hdr.attr_id == CM_REQ_ATTR_ID ||
337 	    mad->mad_hdr.attr_id == CM_SIDR_REQ_ATTR_ID) {
338 		union ib_gid gid;
339 
340 		if (!slave)
341 			return 0;
342 
343 		gid = gid_from_req_msg(ibdev, mad);
344 		*slave = mlx4_ib_find_real_gid(ibdev, port, gid.global.interface_id);
345 		if (*slave < 0) {
346 			mlx4_ib_warn(ibdev, "failed matching slave_id by gid (0x%llx)\n",
347 				     be64_to_cpu(gid.global.interface_id));
348 			return -ENOENT;
349 		}
350 		return 0;
351 	}
352 
353 	pv_cm_id = get_remote_comm_id(mad);
354 	id = id_map_get(ibdev, (int *)&pv_cm_id, -1, -1);
355 
356 	if (!id) {
357 		pr_debug("Couldn't find an entry for pv_cm_id 0x%x\n", pv_cm_id);
358 		return -ENOENT;
359 	}
360 
361 	if (slave)
362 		*slave = id->slave_id;
363 	set_remote_comm_id(mad, id->sl_cm_id);
364 
365 	if (mad->mad_hdr.attr_id == CM_DREQ_ATTR_ID ||
366 	    mad->mad_hdr.attr_id == CM_REJ_ATTR_ID)
367 		schedule_delayed(ibdev, id);
368 
369 	return 0;
370 }
371 
372 void mlx4_ib_cm_paravirt_init(struct mlx4_ib_dev *dev)
373 {
374 	spin_lock_init(&dev->sriov.id_map_lock);
375 	INIT_LIST_HEAD(&dev->sriov.cm_list);
376 	dev->sriov.sl_id_map = RB_ROOT;
377 	xa_init_flags(&dev->sriov.pv_id_table, XA_FLAGS_ALLOC);
378 }
379 
380 /* slave = -1 ==> all slaves */
381 /* TBD -- call paravirt clean for single slave.  Need for slave RESET event */
382 void mlx4_ib_cm_paravirt_clean(struct mlx4_ib_dev *dev, int slave)
383 {
384 	struct mlx4_ib_sriov *sriov = &dev->sriov;
385 	struct rb_root *sl_id_map = &sriov->sl_id_map;
386 	struct list_head lh;
387 	struct rb_node *nd;
388 	int need_flush = 0;
389 	struct id_map_entry *map, *tmp_map;
390 	/* cancel all delayed work queue entries */
391 	INIT_LIST_HEAD(&lh);
392 	spin_lock(&sriov->id_map_lock);
393 	list_for_each_entry_safe(map, tmp_map, &dev->sriov.cm_list, list) {
394 		if (slave < 0 || slave == map->slave_id) {
395 			if (map->scheduled_delete)
396 				need_flush |= !cancel_delayed_work(&map->timeout);
397 		}
398 	}
399 
400 	spin_unlock(&sriov->id_map_lock);
401 
402 	if (need_flush)
403 		flush_scheduled_work(); /* make sure all timers were flushed */
404 
405 	/* now, remove all leftover entries from databases*/
406 	spin_lock(&sriov->id_map_lock);
407 	if (slave < 0) {
408 		while (rb_first(sl_id_map)) {
409 			struct id_map_entry *ent =
410 				rb_entry(rb_first(sl_id_map),
411 					 struct id_map_entry, node);
412 
413 			rb_erase(&ent->node, sl_id_map);
414 			xa_erase(&sriov->pv_id_table, ent->pv_cm_id);
415 		}
416 		list_splice_init(&dev->sriov.cm_list, &lh);
417 	} else {
418 		/* first, move nodes belonging to slave to db remove list */
419 		nd = rb_first(sl_id_map);
420 		while (nd) {
421 			struct id_map_entry *ent =
422 				rb_entry(nd, struct id_map_entry, node);
423 			nd = rb_next(nd);
424 			if (ent->slave_id == slave)
425 				list_move_tail(&ent->list, &lh);
426 		}
427 		/* remove those nodes from databases */
428 		list_for_each_entry_safe(map, tmp_map, &lh, list) {
429 			rb_erase(&map->node, sl_id_map);
430 			xa_erase(&sriov->pv_id_table, map->pv_cm_id);
431 		}
432 
433 		/* add remaining nodes from cm_list */
434 		list_for_each_entry_safe(map, tmp_map, &dev->sriov.cm_list, list) {
435 			if (slave == map->slave_id)
436 				list_move_tail(&map->list, &lh);
437 		}
438 	}
439 
440 	spin_unlock(&sriov->id_map_lock);
441 
442 	/* free any map entries left behind due to cancel_delayed_work above */
443 	list_for_each_entry_safe(map, tmp_map, &lh, list) {
444 		list_del(&map->list);
445 		kfree(map);
446 	}
447 }
448