static void sss_mc_add_rec_to_chain(struct sss_mc_ctx *mcc,
struct sss_mc_rec *rec,
uint32_t hash)
{
struct sss_mc_rec *cur;
uint32_t slot;
slot = mcc->hash_table[hash];
if (slot == MC_INVALID_VAL) {
/* no previous record/collision, just add to hash table */
mcc->hash_table[hash] = MC_PTR_TO_SLOT(mcc->data_table, rec);
return;
}
do {
cur = MC_SLOT_TO_PTR(mcc->data_table, slot, struct sss_mc_rec);
if (cur == rec) {
/* rec already stored in hash chain */
return;
}
slot = cur->next;
} while (slot != MC_INVALID_VAL);
/* end of chain, append our record here */
/* changing a single uint32_t is atomic, so there is no
* need to use barriers in this case */
cur->next = MC_PTR_TO_SLOT(mcc->data_table, rec);
}
static void sss_mc_add_rec_to_chain(struct sss_mc_ctx *mcc,
struct sss_mc_rec *rec,
uint32_t hash)
{
struct sss_mc_rec *cur;
uint32_t slot;
if (hash > MC_HT_ELEMS(mcc->ht_size)) {
/* Invalid hash. This should never happen, but better
* return than trying to access out of bounds memory */
return;
}
slot = mcc->hash_table[hash];
if (slot == MC_INVALID_VAL) {
/* no previous record/collision, just add to hash table */
mcc->hash_table[hash] = MC_PTR_TO_SLOT(mcc->data_table, rec);
return;
}
do {
cur = MC_SLOT_TO_PTR(mcc->data_table, slot, struct sss_mc_rec);
if (cur == rec) {
/* rec already stored in hash chain */
return;
}
slot = sss_mc_next_slot_with_hash(cur, hash);
} while (slot != MC_INVALID_VAL);
/* end of chain, append our record here */
slot = MC_PTR_TO_SLOT(mcc->data_table, rec);
sss_mc_chain_slot_to_record_with_hash(cur, hash, slot);
}
static void sss_mc_free_slots(struct sss_mc_ctx *mcc, struct sss_mc_rec *rec)
{
uint32_t slot;
uint32_t num;
uint32_t i;
slot = MC_PTR_TO_SLOT(mcc->data_table, rec);
num = MC_SIZE_TO_SLOTS(rec->len);
for (i = 0; i < num; i++) {
MC_CLEAR_BIT(mcc->free_table, slot + i);
}
}
static struct sss_mc_rec *sss_mc_get_record(struct sss_mc_ctx *mcc,
size_t rec_len,
struct sized_string *key)
{
struct sss_mc_rec *old_rec = NULL;
struct sss_mc_rec *rec;
int old_slots;
int num_slots;
uint32_t base_slot;
int i;
num_slots = MC_SIZE_TO_SLOTS(rec_len);
old_rec = sss_mc_find_record(mcc, key);
if (old_rec) {
old_slots = MC_SIZE_TO_SLOTS(old_rec->len);
if (old_slots == num_slots) {
return old_rec;
}
/* slot size changed, invalidate record and fall through to get a
* fully new record */
base_slot = MC_PTR_TO_SLOT(mcc->data_table, old_rec);
sss_mc_invalidate_rec(mcc, old_rec);
/* and now free slots */
for (i = 0; i < old_slots; i++) {
MC_CLEAR_BIT(mcc->free_table, base_slot + i);
}
}
/* we are going to use more space, find enough free slots */
base_slot = sss_mc_find_free_slots(mcc, num_slots);
rec = MC_SLOT_TO_PTR(mcc->data_table, base_slot, struct sss_mc_rec);
/* mark as not valid yet */
MC_RAISE_INVALID_BARRIER(rec);
rec->len = rec_len;
rec->next = MC_INVALID_VAL;
MC_LOWER_BARRIER(rec);
/* and now mark slots as used */
for (i = 0; i < num_slots; i++) {
MC_SET_BIT(mcc->free_table, base_slot + i);
}
return rec;
}