1/*
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/vmalloc.h>
9#include <linux/bitops.h>
10#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 = vmalloc(sizeof(struct idset) + bitmap_size(num_ssid, num_id));
29	if (set) {
30		set->num_ssid = num_ssid;
31		set->num_id = num_id;
32		memset(set->bitmap, 0, bitmap_size(num_ssid, num_id));
33	}
34	return set;
35}
36
37void idset_free(struct idset *set)
38{
39	vfree(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}
113
114int idset_is_empty(struct idset *set)
115{
116	int bitnum;
117
118	bitnum = find_first_bit(set->bitmap, set->num_ssid * set->num_id);
119	if (bitnum >= set->num_ssid * set->num_id)
120		return 1;
121	return 0;
122}
123
124void idset_add_set(struct idset *to, struct idset *from)
125{
126	unsigned long i, len;
127
128	len = min(__BITOPS_WORDS(to->num_ssid * to->num_id),
129		  __BITOPS_WORDS(from->num_ssid * from->num_id));
130	for (i = 0; i < len ; i++)
131		to->bitmap[i] |= from->bitmap[i];
132}
133