1/*
2 * Copyright 2020 Red Hat Inc.
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice shall be included in
12 * all copies or substantial portions of the Software.
13 *
14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
17 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
18 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20 * OTHER DEALINGS IN THE SOFTWARE.
21 */
22#include "chid.h"
23
24void
25nvkm_chid_put(struct nvkm_chid *chid, int id, spinlock_t *data_lock)
26{
27	if (id >= 0) {
28		spin_lock_irq(&chid->lock);
29		spin_lock(data_lock);
30		chid->data[id] = NULL;
31		spin_unlock(data_lock);
32		clear_bit(id, chid->used);
33		spin_unlock_irq(&chid->lock);
34	}
35}
36
37int
38nvkm_chid_get(struct nvkm_chid *chid, void *data)
39{
40	int id = -1, cid;
41
42	spin_lock_irq(&chid->lock);
43	cid = find_first_zero_bit(chid->used, chid->nr);
44	if (cid < chid->nr) {
45		set_bit(cid, chid->used);
46		chid->data[cid] = data;
47		id = cid;
48	}
49	spin_unlock_irq(&chid->lock);
50	return id;
51}
52
53static void
54nvkm_chid_del(struct kref *kref)
55{
56	struct nvkm_chid *chid = container_of(kref, typeof(*chid), kref);
57
58	nvkm_event_fini(&chid->event);
59
60	kvfree(chid->data);
61	kfree(chid);
62}
63
64void
65nvkm_chid_unref(struct nvkm_chid **pchid)
66{
67	struct nvkm_chid *chid = *pchid;
68
69	if (!chid)
70		return;
71
72	kref_put(&chid->kref, nvkm_chid_del);
73	*pchid = NULL;
74}
75
76struct nvkm_chid *
77nvkm_chid_ref(struct nvkm_chid *chid)
78{
79	if (chid)
80		kref_get(&chid->kref);
81
82	return chid;
83}
84
85int
86nvkm_chid_new(const struct nvkm_event_func *func, struct nvkm_subdev *subdev,
87	      int nr, int first, int count, struct nvkm_chid **pchid)
88{
89	struct nvkm_chid *chid;
90	int id;
91
92	if (!(chid = *pchid = kzalloc(struct_size(chid, used, nr), GFP_KERNEL)))
93		return -ENOMEM;
94
95	kref_init(&chid->kref);
96	chid->nr = nr;
97	chid->mask = chid->nr - 1;
98	spin_lock_init(&chid->lock);
99
100	if (!(chid->data = kvzalloc(sizeof(*chid->data) * nr, GFP_KERNEL))) {
101		nvkm_chid_unref(pchid);
102		return -ENOMEM;
103	}
104
105	for (id = 0; id < first; id++)
106		__set_bit(id, chid->used);
107	for (id = first + count; id < nr; id++)
108		__set_bit(id, chid->used);
109
110	return nvkm_event_init(func, subdev, 1, nr, &chid->event);
111}
112