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Peter Oberparleiter83b33702007-04-27 16:01:34 +02001/*
2 * drivers/s390/cio/idset.c
3 *
4 * Copyright IBM Corp. 2007
5 * Author(s): Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
6 */
7
8#include <linux/slab.h>
Jiri Slaby1977f032007-10-18 23:40:25 -07009#include <linux/bitops.h>
Peter Oberparleiter83b33702007-04-27 16:01:34 +020010#include "idset.h"
11#include "css.h"
12
13struct idset {
14 int num_ssid;
15 int num_id;
16 unsigned long bitmap[0];
17};
18
19static inline unsigned long bitmap_size(int num_ssid, int num_id)
20{
21 return __BITOPS_WORDS(num_ssid * num_id) * sizeof(unsigned long);
22}
23
24static struct idset *idset_new(int num_ssid, int num_id)
25{
26 struct idset *set;
27
28 set = kzalloc(sizeof(struct idset) + bitmap_size(num_ssid, num_id),
29 GFP_KERNEL);
30 if (set) {
31 set->num_ssid = num_ssid;
32 set->num_id = num_id;
33 }
34 return set;
35}
36
37void idset_free(struct idset *set)
38{
39 kfree(set);
40}
41
42void idset_clear(struct idset *set)
43{
44 memset(set->bitmap, 0, bitmap_size(set->num_ssid, set->num_id));
45}
46
47void idset_fill(struct idset *set)
48{
49 memset(set->bitmap, 0xff, bitmap_size(set->num_ssid, set->num_id));
50}
51
52static inline void idset_add(struct idset *set, int ssid, int id)
53{
54 set_bit(ssid * set->num_id + id, set->bitmap);
55}
56
57static inline void idset_del(struct idset *set, int ssid, int id)
58{
59 clear_bit(ssid * set->num_id + id, set->bitmap);
60}
61
62static inline int idset_contains(struct idset *set, int ssid, int id)
63{
64 return test_bit(ssid * set->num_id + id, set->bitmap);
65}
66
67static inline int idset_get_first(struct idset *set, int *ssid, int *id)
68{
69 int bitnum;
70
71 bitnum = find_first_bit(set->bitmap, set->num_ssid * set->num_id);
72 if (bitnum >= set->num_ssid * set->num_id)
73 return 0;
74 *ssid = bitnum / set->num_id;
75 *id = bitnum % set->num_id;
76 return 1;
77}
78
79struct idset *idset_sch_new(void)
80{
81 return idset_new(__MAX_SSID + 1, __MAX_SUBCHANNEL + 1);
82}
83
84void idset_sch_add(struct idset *set, struct subchannel_id schid)
85{
86 idset_add(set, schid.ssid, schid.sch_no);
87}
88
89void idset_sch_del(struct idset *set, struct subchannel_id schid)
90{
91 idset_del(set, schid.ssid, schid.sch_no);
92}
93
94int idset_sch_contains(struct idset *set, struct subchannel_id schid)
95{
96 return idset_contains(set, schid.ssid, schid.sch_no);
97}
98
99int idset_sch_get_first(struct idset *set, struct subchannel_id *schid)
100{
101 int ssid = 0;
102 int id = 0;
103 int rc;
104
105 rc = idset_get_first(set, &ssid, &id);
106 if (rc) {
107 init_subchannel_id(schid);
108 schid->ssid = ssid;
109 schid->sch_no = id;
110 }
111 return rc;
112}