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gang.c
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1 /*
2  * SPU file system
3  *
4  * (C) Copyright IBM Deutschland Entwicklung GmbH 2005
5  *
6  * Author: Arnd Bergmann <[email protected]>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2, or (at your option)
11  * any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21  */
22 
23 #include <linux/list.h>
24 #include <linux/slab.h>
25 
26 #include "spufs.h"
27 
28 struct spu_gang *alloc_spu_gang(void)
29 {
30  struct spu_gang *gang;
31 
32  gang = kzalloc(sizeof *gang, GFP_KERNEL);
33  if (!gang)
34  goto out;
35 
36  kref_init(&gang->kref);
37  mutex_init(&gang->mutex);
38  mutex_init(&gang->aff_mutex);
39  INIT_LIST_HEAD(&gang->list);
40  INIT_LIST_HEAD(&gang->aff_list_head);
41 
42 out:
43  return gang;
44 }
45 
46 static void destroy_spu_gang(struct kref *kref)
47 {
48  struct spu_gang *gang;
49  gang = container_of(kref, struct spu_gang, kref);
50  WARN_ON(gang->contexts || !list_empty(&gang->list));
51  kfree(gang);
52 }
53 
54 struct spu_gang *get_spu_gang(struct spu_gang *gang)
55 {
56  kref_get(&gang->kref);
57  return gang;
58 }
59 
60 int put_spu_gang(struct spu_gang *gang)
61 {
62  return kref_put(&gang->kref, &destroy_spu_gang);
63 }
64 
65 void spu_gang_add_ctx(struct spu_gang *gang, struct spu_context *ctx)
66 {
67  mutex_lock(&gang->mutex);
68  ctx->gang = get_spu_gang(gang);
69  list_add(&ctx->gang_list, &gang->list);
70  gang->contexts++;
71  mutex_unlock(&gang->mutex);
72 }
73 
74 void spu_gang_remove_ctx(struct spu_gang *gang, struct spu_context *ctx)
75 {
76  mutex_lock(&gang->mutex);
77  WARN_ON(ctx->gang != gang);
78  if (!list_empty(&ctx->aff_list)) {
79  list_del_init(&ctx->aff_list);
80  gang->aff_flags &= ~AFF_OFFSETS_SET;
81  }
82  list_del_init(&ctx->gang_list);
83  gang->contexts--;
84  mutex_unlock(&gang->mutex);
85 
86  put_spu_gang(gang);
87 }