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
44struct 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
57struct cm_generic_msg {
58	struct ib_mad_hdr hdr;
59
60	__be32 local_comm_id;
61	__be32 remote_comm_id;
62};
63
64struct cm_sidr_generic_msg {
65	struct ib_mad_hdr hdr;
66	__be32 request_id;
67};
68
69struct cm_req_msg {
70	unsigned char unused[0x60];
71	union ib_gid primary_path_sgid;
72};
73
74
75static 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
90static 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
105static 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
120static 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
135static 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 */
143static struct id_map_entry *
144id_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
167static 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
186out:
187	list_del(&ent->list);
188	spin_unlock(&sriov->id_map_lock);
189	kfree(ent);
190}
191
192static 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);
206out:
207	spin_unlock(&sriov->id_map_lock);
208}
209
210static 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
242static struct id_map_entry *
243id_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		mlx4_ib_warn(ibdev, "Couldn't allocate id cache entry - out of memory\n");
252		return ERR_PTR(-ENOMEM);
253	}
254
255	ent->sl_cm_id = sl_cm_id;
256	ent->slave_id = slave_id;
257	ent->scheduled_delete = 0;
258	ent->dev = to_mdev(ibdev);
259	INIT_DELAYED_WORK(&ent->timeout, id_map_ent_timeout);
260
261	idr_preload(GFP_KERNEL);
262	spin_lock(&to_mdev(ibdev)->sriov.id_map_lock);
263
264	ret = idr_alloc_cyclic(&sriov->pv_id_table, ent, 0, 0, GFP_NOWAIT);
265	if (ret >= 0) {
266		ent->pv_cm_id = (u32)ret;
267		sl_id_map_add(ibdev, ent);
268		list_add_tail(&ent->list, &sriov->cm_list);
269	}
270
271	spin_unlock(&sriov->id_map_lock);
272	idr_preload_end();
273
274	if (ret >= 0)
275		return ent;
276
277	/*error flow*/
278	kfree(ent);
279	mlx4_ib_warn(ibdev, "No more space in the idr (err:0x%x)\n", ret);
280	return ERR_PTR(-ENOMEM);
281}
282
283static struct id_map_entry *
284id_map_get(struct ib_device *ibdev, int *pv_cm_id, int sl_cm_id, int slave_id)
285{
286	struct id_map_entry *ent;
287	struct mlx4_ib_sriov *sriov = &to_mdev(ibdev)->sriov;
288
289	spin_lock(&sriov->id_map_lock);
290	if (*pv_cm_id == -1) {
291		ent = id_map_find_by_sl_id(ibdev, sl_cm_id, slave_id);
292		if (ent)
293			*pv_cm_id = (int) ent->pv_cm_id;
294	} else
295		ent = (struct id_map_entry *)idr_find(&sriov->pv_id_table, *pv_cm_id);
296	spin_unlock(&sriov->id_map_lock);
297
298	return ent;
299}
300
301static void schedule_delayed(struct ib_device *ibdev, struct id_map_entry *id)
302{
303	struct mlx4_ib_sriov *sriov = &to_mdev(ibdev)->sriov;
304	unsigned long flags;
305
306	spin_lock(&sriov->id_map_lock);
307	spin_lock_irqsave(&sriov->going_down_lock, flags);
308	/*make sure that there is no schedule inside the scheduled work.*/
309	if (!sriov->is_going_down) {
310		id->scheduled_delete = 1;
311		schedule_delayed_work(&id->timeout, CM_CLEANUP_CACHE_TIMEOUT);
312	}
313	spin_unlock_irqrestore(&sriov->going_down_lock, flags);
314	spin_unlock(&sriov->id_map_lock);
315}
316
317int mlx4_ib_multiplex_cm_handler(struct ib_device *ibdev, int port, int slave_id,
318		struct ib_mad *mad)
319{
320	struct id_map_entry *id;
321	u32 sl_cm_id;
322	int pv_cm_id = -1;
323
324	if (mad->mad_hdr.attr_id == CM_REQ_ATTR_ID ||
325			mad->mad_hdr.attr_id == CM_REP_ATTR_ID ||
326			mad->mad_hdr.attr_id == CM_SIDR_REQ_ATTR_ID) {
327		sl_cm_id = get_local_comm_id(mad);
328		id = id_map_alloc(ibdev, slave_id, sl_cm_id);
329		if (IS_ERR(id)) {
330			mlx4_ib_warn(ibdev, "%s: id{slave: %d, sl_cm_id: 0x%x} Failed to id_map_alloc\n",
331				__func__, slave_id, sl_cm_id);
332			return PTR_ERR(id);
333		}
334	} else if (mad->mad_hdr.attr_id == CM_REJ_ATTR_ID ||
335		   mad->mad_hdr.attr_id == CM_SIDR_REP_ATTR_ID) {
336		return 0;
337	} else {
338		sl_cm_id = get_local_comm_id(mad);
339		id = id_map_get(ibdev, &pv_cm_id, slave_id, sl_cm_id);
340	}
341
342	if (!id) {
343		pr_debug("id{slave: %d, sl_cm_id: 0x%x} is NULL!\n",
344			 slave_id, sl_cm_id);
345		return -EINVAL;
346	}
347
348	set_local_comm_id(mad, id->pv_cm_id);
349
350	if (mad->mad_hdr.attr_id == CM_DREQ_ATTR_ID)
351		schedule_delayed(ibdev, id);
352	else if (mad->mad_hdr.attr_id == CM_DREP_ATTR_ID)
353		id_map_find_del(ibdev, pv_cm_id);
354
355	return 0;
356}
357
358int mlx4_ib_demux_cm_handler(struct ib_device *ibdev, int port, int *slave,
359			     struct ib_mad *mad)
360{
361	u32 pv_cm_id;
362	struct id_map_entry *id;
363
364	if (mad->mad_hdr.attr_id == CM_REQ_ATTR_ID ||
365	    mad->mad_hdr.attr_id == CM_SIDR_REQ_ATTR_ID) {
366		union ib_gid gid;
367
368		if (!slave)
369			return 0;
370
371		gid = gid_from_req_msg(ibdev, mad);
372		*slave = mlx4_ib_find_real_gid(ibdev, port, gid.global.interface_id);
373		if (*slave < 0) {
374			mlx4_ib_warn(ibdev, "failed matching slave_id by gid (0x%llx)\n",
375					gid.global.interface_id);
376			return -ENOENT;
377		}
378		return 0;
379	}
380
381	pv_cm_id = get_remote_comm_id(mad);
382	id = id_map_get(ibdev, (int *)&pv_cm_id, -1, -1);
383
384	if (!id) {
385		pr_debug("Couldn't find an entry for pv_cm_id 0x%x\n", pv_cm_id);
386		return -ENOENT;
387	}
388
389	if (slave)
390		*slave = id->slave_id;
391	set_remote_comm_id(mad, id->sl_cm_id);
392
393	if (mad->mad_hdr.attr_id == CM_DREQ_ATTR_ID)
394		schedule_delayed(ibdev, id);
395	else if (mad->mad_hdr.attr_id == CM_REJ_ATTR_ID ||
396			mad->mad_hdr.attr_id == CM_DREP_ATTR_ID) {
397		id_map_find_del(ibdev, (int) pv_cm_id);
398	}
399
400	return 0;
401}
402
403void mlx4_ib_cm_paravirt_init(struct mlx4_ib_dev *dev)
404{
405	spin_lock_init(&dev->sriov.id_map_lock);
406	INIT_LIST_HEAD(&dev->sriov.cm_list);
407	dev->sriov.sl_id_map = RB_ROOT;
408	idr_init(&dev->sriov.pv_id_table);
409}
410
411/* slave = -1 ==> all slaves */
412/* TBD -- call paravirt clean for single slave.  Need for slave RESET event */
413void mlx4_ib_cm_paravirt_clean(struct mlx4_ib_dev *dev, int slave)
414{
415	struct mlx4_ib_sriov *sriov = &dev->sriov;
416	struct rb_root *sl_id_map = &sriov->sl_id_map;
417	struct list_head lh;
418	struct rb_node *nd;
419	int need_flush = 1;
420	struct id_map_entry *map, *tmp_map;
421	/* cancel all delayed work queue entries */
422	INIT_LIST_HEAD(&lh);
423	spin_lock(&sriov->id_map_lock);
424	list_for_each_entry_safe(map, tmp_map, &dev->sriov.cm_list, list) {
425		if (slave < 0 || slave == map->slave_id) {
426			if (map->scheduled_delete)
427				need_flush &= !!cancel_delayed_work(&map->timeout);
428		}
429	}
430
431	spin_unlock(&sriov->id_map_lock);
432
433	if (!need_flush)
434		flush_scheduled_work(); /* make sure all timers were flushed */
435
436	/* now, remove all leftover entries from databases*/
437	spin_lock(&sriov->id_map_lock);
438	if (slave < 0) {
439		while (rb_first(sl_id_map)) {
440			struct id_map_entry *ent =
441				rb_entry(rb_first(sl_id_map),
442					 struct id_map_entry, node);
443
444			rb_erase(&ent->node, sl_id_map);
445			idr_remove(&sriov->pv_id_table, (int) ent->pv_cm_id);
446		}
447		list_splice_init(&dev->sriov.cm_list, &lh);
448	} else {
449		/* first, move nodes belonging to slave to db remove list */
450		nd = rb_first(sl_id_map);
451		while (nd) {
452			struct id_map_entry *ent =
453				rb_entry(nd, struct id_map_entry, node);
454			nd = rb_next(nd);
455			if (ent->slave_id == slave)
456				list_move_tail(&ent->list, &lh);
457		}
458		/* remove those nodes from databases */
459		list_for_each_entry_safe(map, tmp_map, &lh, list) {
460			rb_erase(&map->node, sl_id_map);
461			idr_remove(&sriov->pv_id_table, (int) map->pv_cm_id);
462		}
463
464		/* add remaining nodes from cm_list */
465		list_for_each_entry_safe(map, tmp_map, &dev->sriov.cm_list, list) {
466			if (slave == map->slave_id)
467				list_move_tail(&map->list, &lh);
468		}
469	}
470
471	spin_unlock(&sriov->id_map_lock);
472
473	/* free any map entries left behind due to cancel_delayed_work above */
474	list_for_each_entry_safe(map, tmp_map, &lh, list) {
475		list_del(&map->list);
476		kfree(map);
477	}
478}
479