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 
13 struct idset {
14 	int num_ssid;
15 	int num_id;
16 	unsigned long bitmap[0];
17 };
18 
bitmap_size(int num_ssid,int num_id)19 static 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 
idset_new(int num_ssid,int num_id)24 static 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 
idset_free(struct idset * set)37 void idset_free(struct idset *set)
38 {
39 	vfree(set);
40 }
41 
idset_clear(struct idset * set)42 void idset_clear(struct idset *set)
43 {
44 	memset(set->bitmap, 0, bitmap_size(set->num_ssid, set->num_id));
45 }
46 
idset_fill(struct idset * set)47 void idset_fill(struct idset *set)
48 {
49 	memset(set->bitmap, 0xff, bitmap_size(set->num_ssid, set->num_id));
50 }
51 
idset_add(struct idset * set,int ssid,int id)52 static inline void idset_add(struct idset *set, int ssid, int id)
53 {
54 	set_bit(ssid * set->num_id + id, set->bitmap);
55 }
56 
idset_del(struct idset * set,int ssid,int id)57 static inline void idset_del(struct idset *set, int ssid, int id)
58 {
59 	clear_bit(ssid * set->num_id + id, set->bitmap);
60 }
61 
idset_contains(struct idset * set,int ssid,int id)62 static 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 
idset_get_first(struct idset * set,int * ssid,int * id)67 static 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 
idset_sch_new(void)79 struct idset *idset_sch_new(void)
80 {
81 	return idset_new(max_ssid + 1, __MAX_SUBCHANNEL + 1);
82 }
83 
idset_sch_add(struct idset * set,struct subchannel_id schid)84 void idset_sch_add(struct idset *set, struct subchannel_id schid)
85 {
86 	idset_add(set, schid.ssid, schid.sch_no);
87 }
88 
idset_sch_del(struct idset * set,struct subchannel_id schid)89 void idset_sch_del(struct idset *set, struct subchannel_id schid)
90 {
91 	idset_del(set, schid.ssid, schid.sch_no);
92 }
93 
idset_sch_contains(struct idset * set,struct subchannel_id schid)94 int idset_sch_contains(struct idset *set, struct subchannel_id schid)
95 {
96 	return idset_contains(set, schid.ssid, schid.sch_no);
97 }
98 
idset_sch_get_first(struct idset * set,struct subchannel_id * schid)99 int 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 
idset_is_empty(struct idset * set)114 int 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 
idset_add_set(struct idset * to,struct idset * from)124 void 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