kernel-ark/drivers/s390/cio/idset.c
Sebastian Ott 703e5c9993 [S390] cio: introduce consistent subchannel scanning
Previously, there were multiple subchannel scanning mechanisms
which could potentially conflict with each other. Fix this problem
by moving blacklist and ccw driver triggered scanning to the
existing evaluation method.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-09-22 22:58:42 +02:00

133 lines
2.7 KiB
C

/*
* drivers/s390/cio/idset.c
*
* Copyright IBM Corp. 2007
* Author(s): Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
*/
#include <linux/vmalloc.h>
#include <linux/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 = vmalloc(sizeof(struct idset) + bitmap_size(num_ssid, num_id));
if (set) {
set->num_ssid = num_ssid;
set->num_id = num_id;
memset(set->bitmap, 0, bitmap_size(num_ssid, num_id));
}
return set;
}
void idset_free(struct idset *set)
{
vfree(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;
}
int idset_is_empty(struct idset *set)
{
int bitnum;
bitnum = find_first_bit(set->bitmap, set->num_ssid * set->num_id);
if (bitnum >= set->num_ssid * set->num_id)
return 1;
return 0;
}
void idset_add_set(struct idset *to, struct idset *from)
{
unsigned long i, len;
len = min(__BITOPS_WORDS(to->num_ssid * to->num_id),
__BITOPS_WORDS(from->num_ssid * from->num_id));
for (i = 0; i < len ; i++)
to->bitmap[i] |= from->bitmap[i];
}