/*
* Reuse, or allocate (and program the page pods for) a new DDP buffer. The
* "pages" array is handed over to this function and should not be used in any
* way by the caller after that.
*/
static int
select_ddp_buffer(struct adapter *sc, struct toepcb *toep, vm_page_t *pages,
int npages, int db_off, int db_len)
{
struct ddp_buffer *db;
struct tom_data *td = sc->tom_softc;
int i, empty_slot = -1;
/* Try to reuse */
for (i = 0; i < nitems(toep->db); i++) {
if (bufcmp(toep->db[i], pages, npages, db_off, db_len) == 0) {
free(pages, M_CXGBE);
return (i); /* pages still held */
} else if (toep->db[i] == NULL && empty_slot < 0)
empty_slot = i;
}
/* Allocate new buffer, write its page pods. */
db = alloc_ddp_buffer(td, pages, npages, db_off, db_len);
if (db == NULL) {
vm_page_unhold_pages(pages, npages);
free(pages, M_CXGBE);
return (-1);
}
if (write_page_pods(sc, toep, db) != 0) {
vm_page_unhold_pages(pages, npages);
free_ddp_buffer(td, db);
return (-1);
}
i = empty_slot;
if (i < 0) {
i = arc4random() % nitems(toep->db);
free_ddp_buffer(td, toep->db[i]);
}
toep->db[i] = db;
CTR5(KTR_CXGBE, "%s: tid %d, DDP buffer[%d] = %p (tag 0x%x)",
__func__, toep->tid, i, db, db->tag);
return (i);
}
void
release_ddp_resources(struct toepcb *toep)
{
int i;
for (i = 0; i < nitems(toep->db); i++) {
if (toep->db[i] != NULL) {
free_ddp_buffer(toep->td, toep->db[i]);
toep->db[i] = NULL;
}
}
}
