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
24 void
nvkm_chid_put(struct nvkm_chid * chid,int id,spinlock_t * data_lock)25 nvkm_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
37 int
nvkm_chid_get(struct nvkm_chid * chid,void * data)38 nvkm_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
53 static void
nvkm_chid_del(struct kref * kref)54 nvkm_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
64 void
nvkm_chid_unref(struct nvkm_chid ** pchid)65 nvkm_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
76 struct nvkm_chid *
nvkm_chid_ref(struct nvkm_chid * chid)77 nvkm_chid_ref(struct nvkm_chid *chid)
78 {
79 if (chid)
80 kref_get(&chid->kref);
81
82 return chid;
83 }
84
85 int
nvkm_chid_new(const struct nvkm_event_func * func,struct nvkm_subdev * subdev,int nr,int first,int count,struct nvkm_chid ** pchid)86 nvkm_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