/* Simple round-robin Logical to physical address translation.
*
* Retrieve the mapping using the active append point. Then update the ap for
* the next write to the disk.
*
* Returns rrpc_addr with the physical address and block. Remember to return to
* rrpc->addr_cache when request is finished.
*/
static struct rrpc_addr *rrpc_map_page(struct rrpc *rrpc, sector_t laddr,
int is_gc)
{
struct rrpc_lun *rlun;
struct rrpc_block *rblk;
struct nvm_lun *lun;
u64 paddr;
rlun = rrpc_get_lun_rr(rrpc, is_gc);
lun = rlun->parent;
if (!is_gc && lun->nr_free_blocks < rrpc->nr_luns * 4)
return NULL;
spin_lock(&rlun->lock);
rblk = rlun->cur;
retry:
paddr = rrpc_alloc_addr(rrpc, rblk);
if (paddr == ADDR_EMPTY) {
rblk = rrpc_get_blk(rrpc, rlun, 0);
if (rblk) {
rrpc_set_lun_cur(rlun, rblk);
goto retry;
}
if (is_gc) {
/* retry from emergency gc block */
paddr = rrpc_alloc_addr(rrpc, rlun->gc_cur);
if (paddr == ADDR_EMPTY) {
rblk = rrpc_get_blk(rrpc, rlun, 1);
if (!rblk) {
pr_err("rrpc: no more blocks");
goto err;
}
rlun->gc_cur = rblk;
paddr = rrpc_alloc_addr(rrpc, rlun->gc_cur);
}
rblk = rlun->gc_cur;
}
}
spin_unlock(&rlun->lock);
return rrpc_update_map(rrpc, laddr, rblk, paddr);
err:
spin_unlock(&rlun->lock);
return NULL;
}
paddr = rrpc_alloc_addr(rrpc, rblk);
if (paddr != ADDR_EMPTY)
goto done;
if (!list_empty(&rlun->wblk_list)) {
new_blk:
rblk = list_first_entry(&rlun->wblk_list, struct rrpc_block,
prio);
rrpc_set_lun_cur(rlun, rblk, cur_rblk);
list_del(&rblk->prio);
goto retry;
}
spin_unlock(&rlun->lock);
rblk = rrpc_get_blk(rrpc, rlun, gc_force);
if (rblk) {
spin_lock(&rlun->lock);
list_add_tail(&rblk->prio, &rlun->wblk_list);
/*
* another thread might already have added a new block,
* Therefore, make sure that one is used, instead of the
* one just added.
*/
goto new_blk;
}
if (unlikely(is_gc) && !gc_force) {
/* retry from emergency gc block */
cur_rblk = &rlun->gc_cur;
rblk = rlun->gc_cur;