diff options
Diffstat (limited to 'drivers/s390/cio/idset.c')
-rw-r--r-- | drivers/s390/cio/idset.c | 112 |
1 files changed, 112 insertions, 0 deletions
diff --git a/drivers/s390/cio/idset.c b/drivers/s390/cio/idset.c new file mode 100644 index 00000000000..16ea828e99f --- /dev/null +++ b/drivers/s390/cio/idset.c @@ -0,0 +1,112 @@ +/* + * drivers/s390/cio/idset.c + * + * Copyright IBM Corp. 2007 + * Author(s): Peter Oberparleiter <peter.oberparleiter@de.ibm.com> + */ + +#include <linux/slab.h> +#include <asm/bitops.h> +#include "idset.h" +#include "css.h" + +struct idset { + int num_ssid; + int num_id; + unsigned long bitmap[0]; +}; + +static inline unsigned long bitmap_size(int num_ssid, int num_id) +{ + return __BITOPS_WORDS(num_ssid * num_id) * sizeof(unsigned long); +} + +static struct idset *idset_new(int num_ssid, int num_id) +{ + struct idset *set; + + set = kzalloc(sizeof(struct idset) + bitmap_size(num_ssid, num_id), + GFP_KERNEL); + if (set) { + set->num_ssid = num_ssid; + set->num_id = num_id; + } + return set; +} + +void idset_free(struct idset *set) +{ + kfree(set); +} + +void idset_clear(struct idset *set) +{ + memset(set->bitmap, 0, bitmap_size(set->num_ssid, set->num_id)); +} + +void idset_fill(struct idset *set) +{ + memset(set->bitmap, 0xff, bitmap_size(set->num_ssid, set->num_id)); +} + +static inline void idset_add(struct idset *set, int ssid, int id) +{ + set_bit(ssid * set->num_id + id, set->bitmap); +} + +static inline void idset_del(struct idset *set, int ssid, int id) +{ + clear_bit(ssid * set->num_id + id, set->bitmap); +} + +static inline int idset_contains(struct idset *set, int ssid, int id) +{ + return test_bit(ssid * set->num_id + id, set->bitmap); +} + +static inline int idset_get_first(struct idset *set, int *ssid, int *id) +{ + int bitnum; + + bitnum = find_first_bit(set->bitmap, set->num_ssid * set->num_id); + if (bitnum >= set->num_ssid * set->num_id) + return 0; + *ssid = bitnum / set->num_id; + *id = bitnum % set->num_id; + return 1; +} + +struct idset *idset_sch_new(void) +{ + return idset_new(__MAX_SSID + 1, __MAX_SUBCHANNEL + 1); +} + +void idset_sch_add(struct idset *set, struct subchannel_id schid) +{ + idset_add(set, schid.ssid, schid.sch_no); +} + +void idset_sch_del(struct idset *set, struct subchannel_id schid) +{ + idset_del(set, schid.ssid, schid.sch_no); +} + +int idset_sch_contains(struct idset *set, struct subchannel_id schid) +{ + return idset_contains(set, schid.ssid, schid.sch_no); +} + +int idset_sch_get_first(struct idset *set, struct subchannel_id *schid) +{ + int ssid = 0; + int id = 0; + int rc; + + rc = idset_get_first(set, &ssid, &id); + if (rc) { + init_subchannel_id(schid); + schid->ssid = ssid; + schid->sch_no = id; + } + return rc; +} |