s390/cio/idset.c

0001 // SPDX-License-Identifier: GPL-2.0
0002 /*
0003  *    Copyright IBM Corp. 2007, 2012
0004  *    Author(s): Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
0005  */
0006
0007 #include <linux/vmalloc.h>
0008 #include <linux/bitmap.h>
0009 #include <linux/bitops.h>
0010 #include "idset.h"
0011 #include "css.h"
0012
0013 struct idset {
0014     int num_ssid;
0015     int num_id;
0016     unsigned long bitmap[];
0017 };
0018
0019 static inline unsigned long bitmap_size(int num_ssid, int num_id)
0020 {
0021     return BITS_TO_LONGS(num_ssid * num_id) * sizeof(unsigned long);
0022 }
0023
0024 static struct idset *idset_new(int num_ssid, int num_id)
0025 {
0026     struct idset *set;
0027
0028     set = vmalloc(sizeof(struct idset) + bitmap_size(num_ssid, num_id));
0029     if (set) {
0030         set->num_ssid = num_ssid;
0031         set->num_id = num_id;
0032         memset(set->bitmap, 0, bitmap_size(num_ssid, num_id));
0033     }
0034     return set;
0035 }
0036
0037 void idset_free(struct idset *set)
0038 {
0039     vfree(set);
0040 }
0041
0042 void idset_fill(struct idset *set)
0043 {
0044     memset(set->bitmap, 0xff, bitmap_size(set->num_ssid, set->num_id));
0045 }
0046
0047 static inline void idset_add(struct idset *set, int ssid, int id)
0048 {
0049     set_bit(ssid * set->num_id + id, set->bitmap);
0050 }
0051
0052 static inline void idset_del(struct idset *set, int ssid, int id)
0053 {
0054     clear_bit(ssid * set->num_id + id, set->bitmap);
0055 }
0056
0057 static inline int idset_contains(struct idset *set, int ssid, int id)
0058 {
0059     return test_bit(ssid * set->num_id + id, set->bitmap);
0060 }
0061
0062 struct idset *idset_sch_new(void)
0063 {
0064     return idset_new(max_ssid + 1, __MAX_SUBCHANNEL + 1);
0065 }
0066
0067 void idset_sch_add(struct idset *set, struct subchannel_id schid)
0068 {
0069     idset_add(set, schid.ssid, schid.sch_no);
0070 }
0071
0072 void idset_sch_del(struct idset *set, struct subchannel_id schid)
0073 {
0074     idset_del(set, schid.ssid, schid.sch_no);
0075 }
0076
0077 /* Clear ids starting from @schid up to end of subchannel set. */
0078 void idset_sch_del_subseq(struct idset *set, struct subchannel_id schid)
0079 {
0080     int pos = schid.ssid * set->num_id + schid.sch_no;
0081
0082     bitmap_clear(set->bitmap, pos, set->num_id - schid.sch_no);
0083 }
0084
0085 int idset_sch_contains(struct idset *set, struct subchannel_id schid)
0086 {
0087     return idset_contains(set, schid.ssid, schid.sch_no);
0088 }
0089
0090 int idset_is_empty(struct idset *set)
0091 {
0092     return bitmap_empty(set->bitmap, set->num_ssid * set->num_id);
0093 }
0094
0095 void idset_add_set(struct idset *to, struct idset *from)
0096 {
0097     int len = min(to->num_ssid * to->num_id, from->num_ssid * from->num_id);
0098
0099     bitmap_or(to->bitmap, to->bitmap, from->bitmap, len);
0100 }