static int brb_pop(struct bop_ring_buffer *brb)
{
if (brb_empty(brb))
return -ENODATA;
brb->begin = brb_next(brb, brb->begin);
return 0;
}
static int sm_metadata_count_is_more_than_one(struct dm_space_map *sm,
dm_block_t b, int *result)
{
int r, adjustment = 0;
unsigned i;
struct sm_metadata *smm = container_of(sm, struct sm_metadata, sm);
uint32_t rc;
/*
* We may have some uncommitted adjustments to add. This list
* should always be really short.
*/
for (i = smm->uncommitted.begin;
i != smm->uncommitted.end;
i = brb_next(&smm->uncommitted, i)) {
struct block_op *op = smm->uncommitted.bops + i;
if (op->block != b)
continue;
switch (op->type) {
case BOP_INC:
adjustment++;
break;
case BOP_DEC:
adjustment--;
break;
}
}
if (adjustment > 1) {
*result = 1;
return 0;
}
r = sm_ll_lookup_bitmap(&smm->ll, b, &rc);
if (r)
return r;
if (rc == 3)
/*
* We err on the side of caution, and always return true.
*/
*result = 1;
else
*result = rc + adjustment > 1;
return 0;
}
static int brb_pop(struct bop_ring_buffer *brb, struct block_op *result)
{
struct block_op *bop;
if (brb_empty(brb))
return -ENODATA;
bop = brb->bops + brb->begin;
result->type = bop->type;
result->block = bop->block;
brb->begin = brb_next(brb, brb->begin);
return 0;
}
static int brb_push(struct bop_ring_buffer *brb,
enum block_op_type type, dm_block_t b)
{
struct block_op *bop;
unsigned next = brb_next(brb, brb->end);
/*
* We don't allow the last bop to be filled, this way we can
* differentiate between full and empty.
*/
if (next == brb->begin)
return -ENOMEM;
bop = brb->bops + brb->end;
bop->type = type;
bop->block = b;
brb->end = next;
return 0;
}
static int sm_metadata_get_count(struct dm_space_map *sm, dm_block_t b,
uint32_t *result)
{
int r;
unsigned i;
struct sm_metadata *smm = container_of(sm, struct sm_metadata, sm);
unsigned adjustment = 0;
/*
* We may have some uncommitted adjustments to add. This list
* should always be really short.
*/
for (i = smm->uncommitted.begin;
i != smm->uncommitted.end;
i = brb_next(&smm->uncommitted, i)) {
struct block_op *op = smm->uncommitted.bops + i;
if (op->block != b)
continue;
switch (op->type) {
case BOP_INC:
adjustment++;
break;
case BOP_DEC:
adjustment--;
break;
}
}
r = sm_ll_lookup(&smm->ll, b, result);
if (r)
return r;
*result += adjustment;
return 0;
}