byte * stasis_record_write_begin(int xid, Page * p, recordid rid) {
int page_type = p->pageType;
assert(page_type);
if(p->pageType != SLOTTED_LATCH_FREE_PAGE) {
assert(stasis_record_length_read(xid, p, rid) == stasis_record_type_to_size(rid.size));
}
return page_impls[page_type].recordWrite(xid, p, rid);
}
void stasis_record_write(int xid, Page * p, recordid rid, const byte *dat) {
assert( (p->id == rid.page) && (p->memAddr != NULL) );
assert(rid.size <= BLOB_THRESHOLD_SIZE);
byte * buf = stasis_record_write_begin(xid, p, rid);
memcpy(buf, dat, stasis_record_type_to_size(rid.size));
stasis_record_write_done(xid,p,rid,buf);
assert( (p->id == rid.page) && (p->memAddr != NULL) );
}
static int operate_helper(int xid, Page * p, recordid rid) {
if(stasis_record_type_read(xid, p, rid) == INVALID_SLOT) {
stasis_record_alloc_done(xid, p, rid);
}
assert(stasis_record_length_read(xid, p, rid) == stasis_record_type_to_size(rid.size));
if(rid.size < 0) {
assert(stasis_record_type_read(xid,p,rid) == rid.size);
}
return 0;
}
static int blkSize(block_t * b) {
genericBlockImpl * impl = (genericBlockImpl*)b->impl;
return stasis_record_type_to_size(impl->pos.size);
}
recordid Talloc(int xid, unsigned long size) {
stasis_alloc_t* alloc = stasis_runtime_alloc_state();
short type;
if(size >= BLOB_THRESHOLD_SIZE) {
type = BLOB_SLOT;
} else {
assert(size >= 0);
type = size;
}
recordid rid;
pthread_mutex_lock(&alloc->mut);
pageid_t pageid =
stasis_allocation_policy_pick_suitable_page(alloc->allocPolicy, xid,
stasis_record_type_to_size(type));
if(pageid == INVALID_PAGE) {
stasis_alloc_reserve_new_region(alloc, xid);
pageid = stasis_allocation_policy_pick_suitable_page(alloc->allocPolicy, xid,
stasis_record_type_to_size(type));
}
alloc->lastFreepage = pageid;
Page * p = loadPage(xid, alloc->lastFreepage);
writelock(p->rwlatch, 0);
int rec_size = stasis_record_type_to_size(type);
if(rec_size < 4) { rec_size = 4; }
while(stasis_record_freespace(xid, p) < rec_size) {
stasis_record_compact(p);
int newFreespace = stasis_record_freespace(xid, p);
if(newFreespace >= rec_size) {
break;
}
unlock(p->rwlatch);
stasis_allocation_policy_update_freespace(alloc->allocPolicy, pageid, newFreespace);
releasePage(p);
pageid = stasis_allocation_policy_pick_suitable_page(alloc->allocPolicy, xid,
rec_size);
if(pageid == INVALID_PAGE) {
stasis_alloc_reserve_new_region(alloc, xid);
pageid = stasis_allocation_policy_pick_suitable_page(alloc->allocPolicy, xid,
rec_size);
}
alloc->lastFreepage = pageid;
p = loadPage(xid, alloc->lastFreepage);
writelock(p->rwlatch, 0);
}
rid = stasis_record_alloc_begin(xid, p, type);
assert(rid.size != INVALID_SLOT);
stasis_record_alloc_done(xid, p, rid);
int newFreespace = stasis_record_freespace(xid, p);
stasis_allocation_policy_alloced_from_page(alloc->allocPolicy, xid, pageid);
stasis_allocation_policy_update_freespace(alloc->allocPolicy, pageid, newFreespace);
unlock(p->rwlatch);
alloc_arg a = { rid.slot, type };
Tupdate(xid, rid.page, &a, sizeof(a), OPERATION_ALLOC);
if(type == BLOB_SLOT) {
rid.size = size;
stasis_blob_alloc(xid, rid);
}
releasePage(p);
pthread_mutex_unlock(&alloc->mut);
stasis_transaction_table_set_argument(alloc->xact_table, xid, alloc->callback_id,
AT_COMMIT, alloc);
return rid; // TODO return NULLRID on error
}
