/* target_size is an absolute size */
void
cbuf_mempool_resize(spdid_t spdid, unsigned long target_size)
{
struct cbuf_comp_info *cci;
int diff;
CBUF_TAKE();
cci = cbuf_comp_info_get(spdid);
if (unlikely(!cci)) goto done;
target_size = round_up_to_page(target_size);
diff = (int)(target_size - cci->target_size);
cci->target_size = target_size;
if (diff < 0 && cci->allocated_size > cci->target_size) {
cbuf_shrink(cci, cci->allocated_size - cci->target_size);
}
if (diff > 0) cbuf_expand(cci, diff);
done:
CBUF_RELEASE();
}
static int
cbuf_dropper (cbuf_t cb, int len)
{
/* Discards exactly [len] bytes of unread data from [cb].
* Returns the number of bytes dropped.
*/
assert(cb != NULL);
assert(len > 0);
assert(len <= cb->used);
assert(cbuf_mutex_is_locked(cb));
cb->used -= len;
cb->i_out = (cb->i_out + len) % (cb->size + 1);
/* Attempt to shrink cbuf if possible.
*/
if ((cb->size - cb->used > CBUF_CHUNK) && (cb->size > cb->minsize)) {
cbuf_shrink(cb);
}
/* Don't call me clumsy, don't call me a fool.
* When things fall down on me, I'm following the rule.
*/
return(len);
}
int
cbuf_create(spdid_t spdid, unsigned long size, int cbid)
{
struct cbuf_comp_info *cci;
struct cbuf_info *cbi;
struct cbuf_meta *meta;
struct cbuf_bin *bin;
int ret = 0;
unsigned int id = (unsigned int)cbid;
printl("cbuf_create\n");
if (unlikely(cbid < 0)) return 0;
CBUF_TAKE();
tracking_start(NULL, CBUF_CRT);
cci = cbuf_comp_info_get(spdid);
if (unlikely(!cci)) goto done;
/*
* Client wants to allocate a new cbuf, but the meta might not
* be mapped in.
*/
if (!cbid) {
/* TODO: check if have enough free memory: ask mem manager */
/*memory usage exceeds the target, block this thread*/
if (size + cci->allocated_size > cci->target_size) {
cbuf_shrink(cci, size);
if (size + cci->allocated_size > cci->target_size) {
cbuf_thread_block(cci, size);
return 0;
}
}
cbi = malloc(sizeof(struct cbuf_info));
if (unlikely(!cbi)) goto done;
/* Allocate and map in the cbuf. Discard inconsistent cbufs */
/* TODO: Find a better way to manage those inconsistent cbufs */
do {
id = cmap_add(&cbufs, cbi);
meta = cbuf_meta_lookup(cci, id);
} while(meta && CBUF_INCONSISENT(meta));
cbi->cbid = id;
size = round_up_to_page(size);
cbi->size = size;
cbi->owner.m = NULL;
cbi->owner.spdid = spdid;
INIT_LIST(&cbi->owner, next, prev);
INIT_LIST(cbi, next, prev);
if (cbuf_alloc_map(spdid, &(cbi->owner.addr),
(void**)&(cbi->mem), NULL, size, MAPPING_RW)) {
goto free;
}
}
/* If the client has a cbid, then make sure we agree! */
else {
cbi = cmap_lookup(&cbufs, id);
if (unlikely(!cbi)) goto done;
if (unlikely(cbi->owner.spdid != spdid)) goto done;
}
meta = cbuf_meta_lookup(cci, id);
/* We need to map in the meta for this cbid. Tell the client. */
if (!meta) {
ret = (int)id * -1;
goto done;
}
/*
* Now we know we have a cbid, a backing structure for it, a
* component structure, and the meta mapped in for the cbuf.
* Update the meta with the correct addresses and flags!
*/
memset(meta, 0, sizeof(struct cbuf_meta));
meta->sz = cbi->size >> PAGE_ORDER;
meta->cbid_tag.cbid = id;
CBUF_FLAG_ADD(meta, CBUF_OWNER);
CBUF_PTR_SET(meta, cbi->owner.addr);
CBUF_REFCNT_INC(meta);
/*
* When creates a new cbuf, the manager should be the only
* one who can access the meta
*/
/* TODO: malicious client may trigger this assertion, just for debug */
assert(CBUF_REFCNT(meta) == 1);
assert(CBUF_PTR(meta));
cbi->owner.m = meta;
/*
* Install cbi last. If not, after return a negative cbid,
* collection may happen and get a dangle cbi
*/
bin = cbuf_comp_info_bin_get(cci, size);
if (!bin) bin = cbuf_comp_info_bin_add(cci, size);
if (unlikely(!bin)) goto free;
if (bin->c) ADD_LIST(bin->c, cbi, next, prev);
else bin->c = cbi;
cci->allocated_size += size;
ret = (int)id;
done:
tracking_end(NULL, CBUF_CRT);
CBUF_RELEASE();
return ret;
free:
cmap_del(&cbufs, id);
free(cbi);
goto done;
}
