xref: /linux/drivers/s390/cio/idset.c (revision 621cde16e49b3ecf7d59a8106a20aaebfb4a59a9)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *    Copyright IBM Corp. 2007, 2012
4  *    Author(s): Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
5  */
6 
7 #include <linux/vmalloc.h>
8 #include <linux/bitmap.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[];
17 };
18 
idset_bitmap_size(int num_ssid,int num_id)19 static inline unsigned long idset_bitmap_size(int num_ssid, int num_id)
20 {
21 	return bitmap_size(size_mul(num_ssid, num_id));
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) +
29 		      idset_bitmap_size(num_ssid, num_id));
30 	if (set) {
31 		set->num_ssid = num_ssid;
32 		set->num_id = num_id;
33 		memset(set->bitmap, 0, idset_bitmap_size(num_ssid, num_id));
34 	}
35 	return set;
36 }
37 
idset_free(struct idset * set)38 void idset_free(struct idset *set)
39 {
40 	vfree(set);
41 }
42 
idset_fill(struct idset * set)43 void idset_fill(struct idset *set)
44 {
45 	memset(set->bitmap, 0xff,
46 	       idset_bitmap_size(set->num_ssid, set->num_id));
47 }
48 
idset_add(struct idset * set,int ssid,int id)49 static inline void idset_add(struct idset *set, int ssid, int id)
50 {
51 	set_bit(ssid * set->num_id + id, set->bitmap);
52 }
53 
idset_del(struct idset * set,int ssid,int id)54 static inline void idset_del(struct idset *set, int ssid, int id)
55 {
56 	clear_bit(ssid * set->num_id + id, set->bitmap);
57 }
58 
idset_contains(struct idset * set,int ssid,int id)59 static inline int idset_contains(struct idset *set, int ssid, int id)
60 {
61 	return test_bit(ssid * set->num_id + id, set->bitmap);
62 }
63 
idset_sch_new(void)64 struct idset *idset_sch_new(void)
65 {
66 	return idset_new(max_ssid + 1, __MAX_SUBCHANNEL + 1);
67 }
68 
idset_sch_add(struct idset * set,struct subchannel_id schid)69 void idset_sch_add(struct idset *set, struct subchannel_id schid)
70 {
71 	idset_add(set, schid.ssid, schid.sch_no);
72 }
73 
idset_sch_del(struct idset * set,struct subchannel_id schid)74 void idset_sch_del(struct idset *set, struct subchannel_id schid)
75 {
76 	idset_del(set, schid.ssid, schid.sch_no);
77 }
78 
79 /* Clear ids starting from @schid up to end of subchannel set. */
idset_sch_del_subseq(struct idset * set,struct subchannel_id schid)80 void idset_sch_del_subseq(struct idset *set, struct subchannel_id schid)
81 {
82 	int pos = schid.ssid * set->num_id + schid.sch_no;
83 
84 	bitmap_clear(set->bitmap, pos, set->num_id - schid.sch_no);
85 }
86 
idset_sch_contains(struct idset * set,struct subchannel_id schid)87 int idset_sch_contains(struct idset *set, struct subchannel_id schid)
88 {
89 	return idset_contains(set, schid.ssid, schid.sch_no);
90 }
91 
idset_is_empty(struct idset * set)92 int idset_is_empty(struct idset *set)
93 {
94 	return bitmap_empty(set->bitmap, set->num_ssid * set->num_id);
95 }
96 
idset_add_set(struct idset * to,struct idset * from)97 void idset_add_set(struct idset *to, struct idset *from)
98 {
99 	int len = min(to->num_ssid * to->num_id, from->num_ssid * from->num_id);
100 
101 	bitmap_or(to->bitmap, to->bitmap, from->bitmap, len);
102 }
103