2 * Copyright (C) 2015 IT University of Copenhagen
3 * Initial release: Matias Bjorling <m@bjorling.me>
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License version
7 * 2 as published by the Free Software Foundation.
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * General Public License for more details.
14 * Implementation of a Round-robin page-based Hybrid FTL for Open-channel SSDs.
19 static struct kmem_cache *rrpc_gcb_cache, *rrpc_rq_cache;
20 static DECLARE_RWSEM(rrpc_lock);
22 static int rrpc_submit_io(struct rrpc *rrpc, struct bio *bio,
23 struct nvm_rq *rqd, unsigned long flags);
25 #define rrpc_for_each_lun(rrpc, rlun, i) \
26 for ((i) = 0, rlun = &(rrpc)->luns[0]; \
27 (i) < (rrpc)->nr_luns; (i)++, rlun = &(rrpc)->luns[(i)])
29 static void rrpc_page_invalidate(struct rrpc *rrpc, struct rrpc_addr *a)
31 struct rrpc_block *rblk = a->rblk;
32 unsigned int pg_offset;
34 lockdep_assert_held(&rrpc->rev_lock);
36 if (a->addr == ADDR_EMPTY || !rblk)
39 spin_lock(&rblk->lock);
41 div_u64_rem(a->addr, rrpc->dev->pgs_per_blk, &pg_offset);
42 WARN_ON(test_and_set_bit(pg_offset, rblk->invalid_pages));
43 rblk->nr_invalid_pages++;
45 spin_unlock(&rblk->lock);
47 rrpc->rev_trans_map[a->addr - rrpc->poffset].addr = ADDR_EMPTY;
50 static void rrpc_invalidate_range(struct rrpc *rrpc, sector_t slba,
55 spin_lock(&rrpc->rev_lock);
56 for (i = slba; i < slba + len; i++) {
57 struct rrpc_addr *gp = &rrpc->trans_map[i];
59 rrpc_page_invalidate(rrpc, gp);
62 spin_unlock(&rrpc->rev_lock);
65 static struct nvm_rq *rrpc_inflight_laddr_acquire(struct rrpc *rrpc,
66 sector_t laddr, unsigned int pages)
69 struct rrpc_inflight_rq *inf;
71 rqd = mempool_alloc(rrpc->rq_pool, GFP_ATOMIC);
73 return ERR_PTR(-ENOMEM);
75 inf = rrpc_get_inflight_rq(rqd);
76 if (rrpc_lock_laddr(rrpc, laddr, pages, inf)) {
77 mempool_free(rqd, rrpc->rq_pool);
84 static void rrpc_inflight_laddr_release(struct rrpc *rrpc, struct nvm_rq *rqd)
86 struct rrpc_inflight_rq *inf = rrpc_get_inflight_rq(rqd);
88 rrpc_unlock_laddr(rrpc, inf);
90 mempool_free(rqd, rrpc->rq_pool);
93 static void rrpc_discard(struct rrpc *rrpc, struct bio *bio)
95 sector_t slba = bio->bi_iter.bi_sector / NR_PHY_IN_LOG;
96 sector_t len = bio->bi_iter.bi_size / RRPC_EXPOSED_PAGE_SIZE;
100 rqd = rrpc_inflight_laddr_acquire(rrpc, slba, len);
105 pr_err("rrpc: unable to acquire inflight IO\n");
110 rrpc_invalidate_range(rrpc, slba, len);
111 rrpc_inflight_laddr_release(rrpc, rqd);
114 static int block_is_full(struct rrpc *rrpc, struct rrpc_block *rblk)
116 return (rblk->next_page == rrpc->dev->pgs_per_blk);
119 static u64 block_to_addr(struct rrpc *rrpc, struct rrpc_block *rblk)
121 struct nvm_block *blk = rblk->parent;
123 return blk->id * rrpc->dev->pgs_per_blk;
126 static struct ppa_addr linear_to_generic_addr(struct nvm_dev *dev,
130 int secs, pgs, blks, luns;
131 sector_t ppa = r.ppa;
135 div_u64_rem(ppa, dev->sec_per_pg, &secs);
138 sector_div(ppa, dev->sec_per_pg);
139 div_u64_rem(ppa, dev->sec_per_blk, &pgs);
142 sector_div(ppa, dev->pgs_per_blk);
143 div_u64_rem(ppa, dev->blks_per_lun, &blks);
146 sector_div(ppa, dev->blks_per_lun);
147 div_u64_rem(ppa, dev->luns_per_chnl, &luns);
150 sector_div(ppa, dev->luns_per_chnl);
156 static struct ppa_addr rrpc_ppa_to_gaddr(struct nvm_dev *dev, u64 addr)
158 struct ppa_addr paddr;
161 return linear_to_generic_addr(dev, paddr);
164 /* requires lun->lock taken */
165 static void rrpc_set_lun_cur(struct rrpc_lun *rlun, struct rrpc_block *rblk)
167 struct rrpc *rrpc = rlun->rrpc;
172 spin_lock(&rlun->cur->lock);
173 WARN_ON(!block_is_full(rrpc, rlun->cur));
174 spin_unlock(&rlun->cur->lock);
179 static struct rrpc_block *rrpc_get_blk(struct rrpc *rrpc, struct rrpc_lun *rlun,
182 struct nvm_lun *lun = rlun->parent;
183 struct nvm_block *blk;
184 struct rrpc_block *rblk;
186 spin_lock(&lun->lock);
187 blk = nvm_get_blk_unlocked(rrpc->dev, rlun->parent, flags);
189 pr_err("nvm: rrpc: cannot get new block from media manager\n");
190 spin_unlock(&lun->lock);
194 rblk = &rlun->blocks[blk->id];
195 list_add_tail(&rblk->list, &rlun->open_list);
196 spin_unlock(&lun->lock);
199 bitmap_zero(rblk->invalid_pages, rrpc->dev->pgs_per_blk);
201 rblk->nr_invalid_pages = 0;
202 atomic_set(&rblk->data_cmnt_size, 0);
207 static void rrpc_put_blk(struct rrpc *rrpc, struct rrpc_block *rblk)
209 struct rrpc_lun *rlun = rblk->rlun;
210 struct nvm_lun *lun = rlun->parent;
212 spin_lock(&lun->lock);
213 nvm_put_blk_unlocked(rrpc->dev, rblk->parent);
214 list_del(&rblk->list);
215 spin_unlock(&lun->lock);
218 static void rrpc_put_blks(struct rrpc *rrpc)
220 struct rrpc_lun *rlun;
223 for (i = 0; i < rrpc->nr_luns; i++) {
224 rlun = &rrpc->luns[i];
226 rrpc_put_blk(rrpc, rlun->cur);
228 rrpc_put_blk(rrpc, rlun->gc_cur);
232 static struct rrpc_lun *get_next_lun(struct rrpc *rrpc)
234 int next = atomic_inc_return(&rrpc->next_lun);
236 return &rrpc->luns[next % rrpc->nr_luns];
239 static void rrpc_gc_kick(struct rrpc *rrpc)
241 struct rrpc_lun *rlun;
244 for (i = 0; i < rrpc->nr_luns; i++) {
245 rlun = &rrpc->luns[i];
246 queue_work(rrpc->krqd_wq, &rlun->ws_gc);
251 * timed GC every interval.
253 static void rrpc_gc_timer(unsigned long data)
255 struct rrpc *rrpc = (struct rrpc *)data;
258 mod_timer(&rrpc->gc_timer, jiffies + msecs_to_jiffies(10));
261 static void rrpc_end_sync_bio(struct bio *bio)
263 struct completion *waiting = bio->bi_private;
266 pr_err("nvm: gc request failed (%u).\n", bio->bi_error);
272 * rrpc_move_valid_pages -- migrate live data off the block
273 * @rrpc: the 'rrpc' structure
274 * @block: the block from which to migrate live pages
277 * GC algorithms may call this function to migrate remaining live
278 * pages off the block prior to erasing it. This function blocks
279 * further execution until the operation is complete.
281 static int rrpc_move_valid_pages(struct rrpc *rrpc, struct rrpc_block *rblk)
283 struct request_queue *q = rrpc->dev->q;
284 struct rrpc_rev_addr *rev;
289 int nr_pgs_per_blk = rrpc->dev->pgs_per_blk;
291 DECLARE_COMPLETION_ONSTACK(wait);
293 if (bitmap_full(rblk->invalid_pages, nr_pgs_per_blk))
296 bio = bio_alloc(GFP_NOIO, 1);
298 pr_err("nvm: could not alloc bio to gc\n");
302 page = mempool_alloc(rrpc->page_pool, GFP_NOIO);
308 while ((slot = find_first_zero_bit(rblk->invalid_pages,
309 nr_pgs_per_blk)) < nr_pgs_per_blk) {
312 phys_addr = (rblk->parent->id * nr_pgs_per_blk) + slot;
315 spin_lock(&rrpc->rev_lock);
316 /* Get logical address from physical to logical table */
317 rev = &rrpc->rev_trans_map[phys_addr - rrpc->poffset];
318 /* already updated by previous regular write */
319 if (rev->addr == ADDR_EMPTY) {
320 spin_unlock(&rrpc->rev_lock);
324 rqd = rrpc_inflight_laddr_acquire(rrpc, rev->addr, 1);
325 if (IS_ERR_OR_NULL(rqd)) {
326 spin_unlock(&rrpc->rev_lock);
331 spin_unlock(&rrpc->rev_lock);
333 /* Perform read to do GC */
334 bio->bi_iter.bi_sector = rrpc_get_sector(rev->addr);
336 bio->bi_private = &wait;
337 bio->bi_end_io = rrpc_end_sync_bio;
339 /* TODO: may fail when EXP_PG_SIZE > PAGE_SIZE */
340 bio_add_pc_page(q, bio, page, RRPC_EXPOSED_PAGE_SIZE, 0);
342 if (rrpc_submit_io(rrpc, bio, rqd, NVM_IOTYPE_GC)) {
343 pr_err("rrpc: gc read failed.\n");
344 rrpc_inflight_laddr_release(rrpc, rqd);
347 wait_for_completion_io(&wait);
349 rrpc_inflight_laddr_release(rrpc, rqd);
354 reinit_completion(&wait);
356 bio->bi_iter.bi_sector = rrpc_get_sector(rev->addr);
358 bio->bi_private = &wait;
359 bio->bi_end_io = rrpc_end_sync_bio;
361 bio_add_pc_page(q, bio, page, RRPC_EXPOSED_PAGE_SIZE, 0);
363 /* turn the command around and write the data back to a new
366 if (rrpc_submit_io(rrpc, bio, rqd, NVM_IOTYPE_GC)) {
367 pr_err("rrpc: gc write failed.\n");
368 rrpc_inflight_laddr_release(rrpc, rqd);
371 wait_for_completion_io(&wait);
373 rrpc_inflight_laddr_release(rrpc, rqd);
381 mempool_free(page, rrpc->page_pool);
384 if (!bitmap_full(rblk->invalid_pages, nr_pgs_per_blk)) {
385 pr_err("nvm: failed to garbage collect block\n");
392 static void rrpc_block_gc(struct work_struct *work)
394 struct rrpc_block_gc *gcb = container_of(work, struct rrpc_block_gc,
396 struct rrpc *rrpc = gcb->rrpc;
397 struct rrpc_block *rblk = gcb->rblk;
398 struct nvm_dev *dev = rrpc->dev;
399 struct nvm_lun *lun = rblk->parent->lun;
400 struct rrpc_lun *rlun = &rrpc->luns[lun->id - rrpc->lun_offset];
402 mempool_free(gcb, rrpc->gcb_pool);
403 pr_debug("nvm: block '%lu' being reclaimed\n", rblk->parent->id);
405 if (rrpc_move_valid_pages(rrpc, rblk))
408 if (nvm_erase_blk(dev, rblk->parent))
411 rrpc_put_blk(rrpc, rblk);
416 spin_lock(&rlun->lock);
417 list_add_tail(&rblk->prio, &rlun->prio_list);
418 spin_unlock(&rlun->lock);
421 /* the block with highest number of invalid pages, will be in the beginning
424 static struct rrpc_block *rblock_max_invalid(struct rrpc_block *ra,
425 struct rrpc_block *rb)
427 if (ra->nr_invalid_pages == rb->nr_invalid_pages)
430 return (ra->nr_invalid_pages < rb->nr_invalid_pages) ? rb : ra;
433 /* linearly find the block with highest number of invalid pages
436 static struct rrpc_block *block_prio_find_max(struct rrpc_lun *rlun)
438 struct list_head *prio_list = &rlun->prio_list;
439 struct rrpc_block *rblock, *max;
441 BUG_ON(list_empty(prio_list));
443 max = list_first_entry(prio_list, struct rrpc_block, prio);
444 list_for_each_entry(rblock, prio_list, prio)
445 max = rblock_max_invalid(max, rblock);
450 static void rrpc_lun_gc(struct work_struct *work)
452 struct rrpc_lun *rlun = container_of(work, struct rrpc_lun, ws_gc);
453 struct rrpc *rrpc = rlun->rrpc;
454 struct nvm_lun *lun = rlun->parent;
455 struct rrpc_block_gc *gcb;
456 unsigned int nr_blocks_need;
458 nr_blocks_need = rrpc->dev->blks_per_lun / GC_LIMIT_INVERSE;
460 if (nr_blocks_need < rrpc->nr_luns)
461 nr_blocks_need = rrpc->nr_luns;
463 spin_lock(&rlun->lock);
464 while (nr_blocks_need > lun->nr_free_blocks &&
465 !list_empty(&rlun->prio_list)) {
466 struct rrpc_block *rblock = block_prio_find_max(rlun);
467 struct nvm_block *block = rblock->parent;
469 if (!rblock->nr_invalid_pages)
472 gcb = mempool_alloc(rrpc->gcb_pool, GFP_ATOMIC);
476 list_del_init(&rblock->prio);
478 BUG_ON(!block_is_full(rrpc, rblock));
480 pr_debug("rrpc: selected block '%lu' for GC\n", block->id);
484 INIT_WORK(&gcb->ws_gc, rrpc_block_gc);
486 queue_work(rrpc->kgc_wq, &gcb->ws_gc);
490 spin_unlock(&rlun->lock);
492 /* TODO: Hint that request queue can be started again */
495 static void rrpc_gc_queue(struct work_struct *work)
497 struct rrpc_block_gc *gcb = container_of(work, struct rrpc_block_gc,
499 struct rrpc *rrpc = gcb->rrpc;
500 struct rrpc_block *rblk = gcb->rblk;
501 struct nvm_lun *lun = rblk->parent->lun;
502 struct rrpc_lun *rlun = &rrpc->luns[lun->id - rrpc->lun_offset];
504 spin_lock(&rlun->lock);
505 list_add_tail(&rblk->prio, &rlun->prio_list);
506 spin_unlock(&rlun->lock);
508 mempool_free(gcb, rrpc->gcb_pool);
509 pr_debug("nvm: block '%lu' is full, allow GC (sched)\n",
513 static const struct block_device_operations rrpc_fops = {
514 .owner = THIS_MODULE,
517 static struct rrpc_lun *rrpc_get_lun_rr(struct rrpc *rrpc, int is_gc)
520 struct rrpc_lun *rlun, *max_free;
523 return get_next_lun(rrpc);
525 /* during GC, we don't care about RR, instead we want to make
526 * sure that we maintain evenness between the block luns.
528 max_free = &rrpc->luns[0];
529 /* prevent GC-ing lun from devouring pages of a lun with
530 * little free blocks. We don't take the lock as we only need an
533 rrpc_for_each_lun(rrpc, rlun, i) {
534 if (rlun->parent->nr_free_blocks >
535 max_free->parent->nr_free_blocks)
542 static struct rrpc_addr *rrpc_update_map(struct rrpc *rrpc, sector_t laddr,
543 struct rrpc_block *rblk, u64 paddr)
545 struct rrpc_addr *gp;
546 struct rrpc_rev_addr *rev;
548 BUG_ON(laddr >= rrpc->nr_pages);
550 gp = &rrpc->trans_map[laddr];
551 spin_lock(&rrpc->rev_lock);
553 rrpc_page_invalidate(rrpc, gp);
558 rev = &rrpc->rev_trans_map[gp->addr - rrpc->poffset];
560 spin_unlock(&rrpc->rev_lock);
565 static u64 rrpc_alloc_addr(struct rrpc *rrpc, struct rrpc_block *rblk)
567 u64 addr = ADDR_EMPTY;
569 spin_lock(&rblk->lock);
570 if (block_is_full(rrpc, rblk))
573 addr = block_to_addr(rrpc, rblk) + rblk->next_page;
577 spin_unlock(&rblk->lock);
581 /* Simple round-robin Logical to physical address translation.
583 * Retrieve the mapping using the active append point. Then update the ap for
584 * the next write to the disk.
586 * Returns rrpc_addr with the physical address and block. Remember to return to
587 * rrpc->addr_cache when request is finished.
589 static struct rrpc_addr *rrpc_map_page(struct rrpc *rrpc, sector_t laddr,
592 struct rrpc_lun *rlun;
593 struct rrpc_block *rblk;
597 rlun = rrpc_get_lun_rr(rrpc, is_gc);
600 if (!is_gc && lun->nr_free_blocks < rrpc->nr_luns * 4)
603 spin_lock(&rlun->lock);
607 paddr = rrpc_alloc_addr(rrpc, rblk);
609 if (paddr == ADDR_EMPTY) {
610 rblk = rrpc_get_blk(rrpc, rlun, 0);
612 rrpc_set_lun_cur(rlun, rblk);
617 /* retry from emergency gc block */
618 paddr = rrpc_alloc_addr(rrpc, rlun->gc_cur);
619 if (paddr == ADDR_EMPTY) {
620 rblk = rrpc_get_blk(rrpc, rlun, 1);
622 pr_err("rrpc: no more blocks");
627 paddr = rrpc_alloc_addr(rrpc, rlun->gc_cur);
633 spin_unlock(&rlun->lock);
634 return rrpc_update_map(rrpc, laddr, rblk, paddr);
636 spin_unlock(&rlun->lock);
640 static void rrpc_run_gc(struct rrpc *rrpc, struct rrpc_block *rblk)
642 struct rrpc_block_gc *gcb;
644 gcb = mempool_alloc(rrpc->gcb_pool, GFP_ATOMIC);
646 pr_err("rrpc: unable to queue block for gc.");
653 INIT_WORK(&gcb->ws_gc, rrpc_gc_queue);
654 queue_work(rrpc->kgc_wq, &gcb->ws_gc);
657 static void rrpc_end_io_write(struct rrpc *rrpc, struct rrpc_rq *rrqd,
658 sector_t laddr, uint8_t npages)
661 struct rrpc_block *rblk;
665 for (i = 0; i < npages; i++) {
666 p = &rrpc->trans_map[laddr + i];
668 lun = rblk->parent->lun;
670 cmnt_size = atomic_inc_return(&rblk->data_cmnt_size);
671 if (unlikely(cmnt_size == rrpc->dev->pgs_per_blk)) {
672 struct nvm_block *blk = rblk->parent;
673 struct rrpc_lun *rlun = rblk->rlun;
675 spin_lock(&lun->lock);
676 lun->nr_open_blocks--;
677 lun->nr_closed_blocks++;
678 blk->state &= ~NVM_BLK_ST_OPEN;
679 blk->state |= NVM_BLK_ST_CLOSED;
680 list_move_tail(&rblk->list, &rlun->closed_list);
681 spin_unlock(&lun->lock);
683 rrpc_run_gc(rrpc, rblk);
688 static void rrpc_end_io(struct nvm_rq *rqd)
690 struct rrpc *rrpc = container_of(rqd->ins, struct rrpc, instance);
691 struct rrpc_rq *rrqd = nvm_rq_to_pdu(rqd);
692 uint8_t npages = rqd->nr_pages;
693 sector_t laddr = rrpc_get_laddr(rqd->bio) - npages;
695 if (bio_data_dir(rqd->bio) == WRITE)
696 rrpc_end_io_write(rrpc, rrqd, laddr, npages);
700 if (rrqd->flags & NVM_IOTYPE_GC)
703 rrpc_unlock_rq(rrpc, rqd);
706 nvm_dev_dma_free(rrpc->dev, rqd->ppa_list, rqd->dma_ppa_list);
708 nvm_dev_dma_free(rrpc->dev, rqd->metadata, rqd->dma_metadata);
710 mempool_free(rqd, rrpc->rq_pool);
713 static int rrpc_read_ppalist_rq(struct rrpc *rrpc, struct bio *bio,
714 struct nvm_rq *rqd, unsigned long flags, int npages)
716 struct rrpc_inflight_rq *r = rrpc_get_inflight_rq(rqd);
717 struct rrpc_addr *gp;
718 sector_t laddr = rrpc_get_laddr(bio);
719 int is_gc = flags & NVM_IOTYPE_GC;
722 if (!is_gc && rrpc_lock_rq(rrpc, bio, rqd)) {
723 nvm_dev_dma_free(rrpc->dev, rqd->ppa_list, rqd->dma_ppa_list);
724 return NVM_IO_REQUEUE;
727 for (i = 0; i < npages; i++) {
728 /* We assume that mapping occurs at 4KB granularity */
729 BUG_ON(!(laddr + i >= 0 && laddr + i < rrpc->nr_pages));
730 gp = &rrpc->trans_map[laddr + i];
733 rqd->ppa_list[i] = rrpc_ppa_to_gaddr(rrpc->dev,
737 rrpc_unlock_laddr(rrpc, r);
738 nvm_dev_dma_free(rrpc->dev, rqd->ppa_list,
744 rqd->opcode = NVM_OP_HBREAD;
749 static int rrpc_read_rq(struct rrpc *rrpc, struct bio *bio, struct nvm_rq *rqd,
752 struct rrpc_rq *rrqd = nvm_rq_to_pdu(rqd);
753 int is_gc = flags & NVM_IOTYPE_GC;
754 sector_t laddr = rrpc_get_laddr(bio);
755 struct rrpc_addr *gp;
757 if (!is_gc && rrpc_lock_rq(rrpc, bio, rqd))
758 return NVM_IO_REQUEUE;
760 BUG_ON(!(laddr >= 0 && laddr < rrpc->nr_pages));
761 gp = &rrpc->trans_map[laddr];
764 rqd->ppa_addr = rrpc_ppa_to_gaddr(rrpc->dev, gp->addr);
767 rrpc_unlock_rq(rrpc, rqd);
771 rqd->opcode = NVM_OP_HBREAD;
777 static int rrpc_write_ppalist_rq(struct rrpc *rrpc, struct bio *bio,
778 struct nvm_rq *rqd, unsigned long flags, int npages)
780 struct rrpc_inflight_rq *r = rrpc_get_inflight_rq(rqd);
782 sector_t laddr = rrpc_get_laddr(bio);
783 int is_gc = flags & NVM_IOTYPE_GC;
786 if (!is_gc && rrpc_lock_rq(rrpc, bio, rqd)) {
787 nvm_dev_dma_free(rrpc->dev, rqd->ppa_list, rqd->dma_ppa_list);
788 return NVM_IO_REQUEUE;
791 for (i = 0; i < npages; i++) {
792 /* We assume that mapping occurs at 4KB granularity */
793 p = rrpc_map_page(rrpc, laddr + i, is_gc);
796 rrpc_unlock_laddr(rrpc, r);
797 nvm_dev_dma_free(rrpc->dev, rqd->ppa_list,
800 return NVM_IO_REQUEUE;
803 rqd->ppa_list[i] = rrpc_ppa_to_gaddr(rrpc->dev,
807 rqd->opcode = NVM_OP_HBWRITE;
812 static int rrpc_write_rq(struct rrpc *rrpc, struct bio *bio,
813 struct nvm_rq *rqd, unsigned long flags)
815 struct rrpc_rq *rrqd = nvm_rq_to_pdu(rqd);
817 int is_gc = flags & NVM_IOTYPE_GC;
818 sector_t laddr = rrpc_get_laddr(bio);
820 if (!is_gc && rrpc_lock_rq(rrpc, bio, rqd))
821 return NVM_IO_REQUEUE;
823 p = rrpc_map_page(rrpc, laddr, is_gc);
826 rrpc_unlock_rq(rrpc, rqd);
828 return NVM_IO_REQUEUE;
831 rqd->ppa_addr = rrpc_ppa_to_gaddr(rrpc->dev, p->addr);
832 rqd->opcode = NVM_OP_HBWRITE;
838 static int rrpc_setup_rq(struct rrpc *rrpc, struct bio *bio,
839 struct nvm_rq *rqd, unsigned long flags, uint8_t npages)
842 rqd->ppa_list = nvm_dev_dma_alloc(rrpc->dev, GFP_KERNEL,
844 if (!rqd->ppa_list) {
845 pr_err("rrpc: not able to allocate ppa list\n");
849 if (bio_rw(bio) == WRITE)
850 return rrpc_write_ppalist_rq(rrpc, bio, rqd, flags,
853 return rrpc_read_ppalist_rq(rrpc, bio, rqd, flags, npages);
856 if (bio_rw(bio) == WRITE)
857 return rrpc_write_rq(rrpc, bio, rqd, flags);
859 return rrpc_read_rq(rrpc, bio, rqd, flags);
862 static int rrpc_submit_io(struct rrpc *rrpc, struct bio *bio,
863 struct nvm_rq *rqd, unsigned long flags)
866 struct rrpc_rq *rrq = nvm_rq_to_pdu(rqd);
867 uint8_t nr_pages = rrpc_get_pages(bio);
868 int bio_size = bio_sectors(bio) << 9;
870 if (bio_size < rrpc->dev->sec_size)
872 else if (bio_size > rrpc->dev->max_rq_size)
875 err = rrpc_setup_rq(rrpc, bio, rqd, flags, nr_pages);
881 rqd->ins = &rrpc->instance;
882 rqd->nr_pages = nr_pages;
885 err = nvm_submit_io(rrpc->dev, rqd);
887 pr_err("rrpc: I/O submission failed: %d\n", err);
889 if (!(flags & NVM_IOTYPE_GC)) {
890 rrpc_unlock_rq(rrpc, rqd);
891 if (rqd->nr_pages > 1)
892 nvm_dev_dma_free(rrpc->dev,
893 rqd->ppa_list, rqd->dma_ppa_list);
901 static blk_qc_t rrpc_make_rq(struct request_queue *q, struct bio *bio)
903 struct rrpc *rrpc = q->queuedata;
907 if (bio->bi_rw & REQ_DISCARD) {
908 rrpc_discard(rrpc, bio);
909 return BLK_QC_T_NONE;
912 rqd = mempool_alloc(rrpc->rq_pool, GFP_KERNEL);
914 pr_err_ratelimited("rrpc: not able to queue bio.");
916 return BLK_QC_T_NONE;
918 memset(rqd, 0, sizeof(struct nvm_rq));
920 err = rrpc_submit_io(rrpc, bio, rqd, NVM_IOTYPE_NONE);
923 return BLK_QC_T_NONE;
931 spin_lock(&rrpc->bio_lock);
932 bio_list_add(&rrpc->requeue_bios, bio);
933 spin_unlock(&rrpc->bio_lock);
934 queue_work(rrpc->kgc_wq, &rrpc->ws_requeue);
938 mempool_free(rqd, rrpc->rq_pool);
939 return BLK_QC_T_NONE;
942 static void rrpc_requeue(struct work_struct *work)
944 struct rrpc *rrpc = container_of(work, struct rrpc, ws_requeue);
945 struct bio_list bios;
948 bio_list_init(&bios);
950 spin_lock(&rrpc->bio_lock);
951 bio_list_merge(&bios, &rrpc->requeue_bios);
952 bio_list_init(&rrpc->requeue_bios);
953 spin_unlock(&rrpc->bio_lock);
955 while ((bio = bio_list_pop(&bios)))
956 rrpc_make_rq(rrpc->disk->queue, bio);
959 static void rrpc_gc_free(struct rrpc *rrpc)
961 struct rrpc_lun *rlun;
965 destroy_workqueue(rrpc->krqd_wq);
968 destroy_workqueue(rrpc->kgc_wq);
973 for (i = 0; i < rrpc->nr_luns; i++) {
974 rlun = &rrpc->luns[i];
982 static int rrpc_gc_init(struct rrpc *rrpc)
984 rrpc->krqd_wq = alloc_workqueue("rrpc-lun", WQ_MEM_RECLAIM|WQ_UNBOUND,
989 rrpc->kgc_wq = alloc_workqueue("rrpc-bg", WQ_MEM_RECLAIM, 1);
993 setup_timer(&rrpc->gc_timer, rrpc_gc_timer, (unsigned long)rrpc);
998 static void rrpc_map_free(struct rrpc *rrpc)
1000 vfree(rrpc->rev_trans_map);
1001 vfree(rrpc->trans_map);
1004 static int rrpc_l2p_update(u64 slba, u32 nlb, __le64 *entries, void *private)
1006 struct rrpc *rrpc = (struct rrpc *)private;
1007 struct nvm_dev *dev = rrpc->dev;
1008 struct rrpc_addr *addr = rrpc->trans_map + slba;
1009 struct rrpc_rev_addr *raddr = rrpc->rev_trans_map;
1010 sector_t max_pages = dev->total_pages * (dev->sec_size >> 9);
1011 u64 elba = slba + nlb;
1014 if (unlikely(elba > dev->total_pages)) {
1015 pr_err("nvm: L2P data from device is out of bounds!\n");
1019 for (i = 0; i < nlb; i++) {
1020 u64 pba = le64_to_cpu(entries[i]);
1021 /* LNVM treats address-spaces as silos, LBA and PBA are
1022 * equally large and zero-indexed.
1024 if (unlikely(pba >= max_pages && pba != U64_MAX)) {
1025 pr_err("nvm: L2P data entry is out of bounds!\n");
1029 /* Address zero is a special one. The first page on a disk is
1030 * protected. As it often holds internal device boot
1037 raddr[pba].addr = slba + i;
1043 static int rrpc_map_init(struct rrpc *rrpc)
1045 struct nvm_dev *dev = rrpc->dev;
1049 rrpc->trans_map = vzalloc(sizeof(struct rrpc_addr) * rrpc->nr_pages);
1050 if (!rrpc->trans_map)
1053 rrpc->rev_trans_map = vmalloc(sizeof(struct rrpc_rev_addr)
1055 if (!rrpc->rev_trans_map)
1058 for (i = 0; i < rrpc->nr_pages; i++) {
1059 struct rrpc_addr *p = &rrpc->trans_map[i];
1060 struct rrpc_rev_addr *r = &rrpc->rev_trans_map[i];
1062 p->addr = ADDR_EMPTY;
1063 r->addr = ADDR_EMPTY;
1066 if (!dev->ops->get_l2p_tbl)
1069 /* Bring up the mapping table from device */
1070 ret = dev->ops->get_l2p_tbl(dev, 0, dev->total_pages,
1071 rrpc_l2p_update, rrpc);
1073 pr_err("nvm: rrpc: could not read L2P table.\n");
1081 /* Minimum pages needed within a lun */
1082 #define PAGE_POOL_SIZE 16
1083 #define ADDR_POOL_SIZE 64
1085 static int rrpc_core_init(struct rrpc *rrpc)
1087 down_write(&rrpc_lock);
1088 if (!rrpc_gcb_cache) {
1089 rrpc_gcb_cache = kmem_cache_create("rrpc_gcb",
1090 sizeof(struct rrpc_block_gc), 0, 0, NULL);
1091 if (!rrpc_gcb_cache) {
1092 up_write(&rrpc_lock);
1096 rrpc_rq_cache = kmem_cache_create("rrpc_rq",
1097 sizeof(struct nvm_rq) + sizeof(struct rrpc_rq),
1099 if (!rrpc_rq_cache) {
1100 kmem_cache_destroy(rrpc_gcb_cache);
1101 up_write(&rrpc_lock);
1105 up_write(&rrpc_lock);
1107 rrpc->page_pool = mempool_create_page_pool(PAGE_POOL_SIZE, 0);
1108 if (!rrpc->page_pool)
1111 rrpc->gcb_pool = mempool_create_slab_pool(rrpc->dev->nr_luns,
1113 if (!rrpc->gcb_pool)
1116 rrpc->rq_pool = mempool_create_slab_pool(64, rrpc_rq_cache);
1120 spin_lock_init(&rrpc->inflights.lock);
1121 INIT_LIST_HEAD(&rrpc->inflights.reqs);
1126 static void rrpc_core_free(struct rrpc *rrpc)
1128 mempool_destroy(rrpc->page_pool);
1129 mempool_destroy(rrpc->gcb_pool);
1130 mempool_destroy(rrpc->rq_pool);
1133 static void rrpc_luns_free(struct rrpc *rrpc)
1138 static int rrpc_luns_init(struct rrpc *rrpc, int lun_begin, int lun_end)
1140 struct nvm_dev *dev = rrpc->dev;
1141 struct rrpc_lun *rlun;
1144 if (dev->pgs_per_blk > MAX_INVALID_PAGES_STORAGE * BITS_PER_LONG) {
1145 pr_err("rrpc: number of pages per block too high.");
1149 spin_lock_init(&rrpc->rev_lock);
1151 rrpc->luns = kcalloc(rrpc->nr_luns, sizeof(struct rrpc_lun),
1157 for (i = 0; i < rrpc->nr_luns; i++) {
1158 struct nvm_lun *lun = dev->mt->get_lun(dev, lun_begin + i);
1160 rlun = &rrpc->luns[i];
1163 INIT_LIST_HEAD(&rlun->prio_list);
1164 INIT_LIST_HEAD(&rlun->open_list);
1165 INIT_LIST_HEAD(&rlun->closed_list);
1167 INIT_WORK(&rlun->ws_gc, rrpc_lun_gc);
1168 spin_lock_init(&rlun->lock);
1170 rrpc->total_blocks += dev->blks_per_lun;
1171 rrpc->nr_pages += dev->sec_per_lun;
1173 rlun->blocks = vzalloc(sizeof(struct rrpc_block) *
1174 rrpc->dev->blks_per_lun);
1178 for (j = 0; j < rrpc->dev->blks_per_lun; j++) {
1179 struct rrpc_block *rblk = &rlun->blocks[j];
1180 struct nvm_block *blk = &lun->blocks[j];
1184 INIT_LIST_HEAD(&rblk->prio);
1185 spin_lock_init(&rblk->lock);
1194 static void rrpc_free(struct rrpc *rrpc)
1197 rrpc_map_free(rrpc);
1198 rrpc_core_free(rrpc);
1199 rrpc_luns_free(rrpc);
1204 static void rrpc_exit(void *private)
1206 struct rrpc *rrpc = private;
1208 del_timer(&rrpc->gc_timer);
1210 flush_workqueue(rrpc->krqd_wq);
1211 flush_workqueue(rrpc->kgc_wq);
1216 static sector_t rrpc_capacity(void *private)
1218 struct rrpc *rrpc = private;
1219 struct nvm_dev *dev = rrpc->dev;
1220 sector_t reserved, provisioned;
1222 /* cur, gc, and two emergency blocks for each lun */
1223 reserved = rrpc->nr_luns * dev->max_pages_per_blk * 4;
1224 provisioned = rrpc->nr_pages - reserved;
1226 if (reserved > rrpc->nr_pages) {
1227 pr_err("rrpc: not enough space available to expose storage.\n");
1231 sector_div(provisioned, 10);
1232 return provisioned * 9 * NR_PHY_IN_LOG;
1236 * Looks up the logical address from reverse trans map and check if its valid by
1237 * comparing the logical to physical address with the physical address.
1238 * Returns 0 on free, otherwise 1 if in use
1240 static void rrpc_block_map_update(struct rrpc *rrpc, struct rrpc_block *rblk)
1242 struct nvm_dev *dev = rrpc->dev;
1244 struct rrpc_addr *laddr;
1247 for (offset = 0; offset < dev->pgs_per_blk; offset++) {
1248 paddr = block_to_addr(rrpc, rblk) + offset;
1250 pladdr = rrpc->rev_trans_map[paddr].addr;
1251 if (pladdr == ADDR_EMPTY)
1254 laddr = &rrpc->trans_map[pladdr];
1256 if (paddr == laddr->addr) {
1259 set_bit(offset, rblk->invalid_pages);
1260 rblk->nr_invalid_pages++;
1265 static int rrpc_blocks_init(struct rrpc *rrpc)
1267 struct rrpc_lun *rlun;
1268 struct rrpc_block *rblk;
1269 int lun_iter, blk_iter;
1271 for (lun_iter = 0; lun_iter < rrpc->nr_luns; lun_iter++) {
1272 rlun = &rrpc->luns[lun_iter];
1274 for (blk_iter = 0; blk_iter < rrpc->dev->blks_per_lun;
1276 rblk = &rlun->blocks[blk_iter];
1277 rrpc_block_map_update(rrpc, rblk);
1284 static int rrpc_luns_configure(struct rrpc *rrpc)
1286 struct rrpc_lun *rlun;
1287 struct rrpc_block *rblk;
1290 for (i = 0; i < rrpc->nr_luns; i++) {
1291 rlun = &rrpc->luns[i];
1293 rblk = rrpc_get_blk(rrpc, rlun, 0);
1297 rrpc_set_lun_cur(rlun, rblk);
1299 /* Emergency gc block */
1300 rblk = rrpc_get_blk(rrpc, rlun, 1);
1303 rlun->gc_cur = rblk;
1308 rrpc_put_blks(rrpc);
1312 static struct nvm_tgt_type tt_rrpc;
1314 static void *rrpc_init(struct nvm_dev *dev, struct gendisk *tdisk,
1315 int lun_begin, int lun_end)
1317 struct request_queue *bqueue = dev->q;
1318 struct request_queue *tqueue = tdisk->queue;
1322 if (!(dev->identity.dom & NVM_RSP_L2P)) {
1323 pr_err("nvm: rrpc: device does not support l2p (%x)\n",
1325 return ERR_PTR(-EINVAL);
1328 rrpc = kzalloc(sizeof(struct rrpc), GFP_KERNEL);
1330 return ERR_PTR(-ENOMEM);
1332 rrpc->instance.tt = &tt_rrpc;
1336 bio_list_init(&rrpc->requeue_bios);
1337 spin_lock_init(&rrpc->bio_lock);
1338 INIT_WORK(&rrpc->ws_requeue, rrpc_requeue);
1340 rrpc->nr_luns = lun_end - lun_begin + 1;
1342 /* simple round-robin strategy */
1343 atomic_set(&rrpc->next_lun, -1);
1345 ret = rrpc_luns_init(rrpc, lun_begin, lun_end);
1347 pr_err("nvm: rrpc: could not initialize luns\n");
1351 rrpc->poffset = dev->sec_per_lun * lun_begin;
1352 rrpc->lun_offset = lun_begin;
1354 ret = rrpc_core_init(rrpc);
1356 pr_err("nvm: rrpc: could not initialize core\n");
1360 ret = rrpc_map_init(rrpc);
1362 pr_err("nvm: rrpc: could not initialize maps\n");
1366 ret = rrpc_blocks_init(rrpc);
1368 pr_err("nvm: rrpc: could not initialize state for blocks\n");
1372 ret = rrpc_luns_configure(rrpc);
1374 pr_err("nvm: rrpc: not enough blocks available in LUNs.\n");
1378 ret = rrpc_gc_init(rrpc);
1380 pr_err("nvm: rrpc: could not initialize gc\n");
1384 /* inherit the size from the underlying device */
1385 blk_queue_logical_block_size(tqueue, queue_physical_block_size(bqueue));
1386 blk_queue_max_hw_sectors(tqueue, queue_max_hw_sectors(bqueue));
1388 pr_info("nvm: rrpc initialized with %u luns and %llu pages.\n",
1389 rrpc->nr_luns, (unsigned long long)rrpc->nr_pages);
1391 mod_timer(&rrpc->gc_timer, jiffies + msecs_to_jiffies(10));
1396 return ERR_PTR(ret);
1399 /* round robin, page-based FTL, and cost-based GC */
1400 static struct nvm_tgt_type tt_rrpc = {
1402 .version = {1, 0, 0},
1404 .make_rq = rrpc_make_rq,
1405 .capacity = rrpc_capacity,
1406 .end_io = rrpc_end_io,
1412 static int __init rrpc_module_init(void)
1414 return nvm_register_target(&tt_rrpc);
1417 static void rrpc_module_exit(void)
1419 nvm_unregister_target(&tt_rrpc);
1422 module_init(rrpc_module_init);
1423 module_exit(rrpc_module_exit);
1424 MODULE_LICENSE("GPL v2");
1425 MODULE_DESCRIPTION("Block-Device Target for Open-Channel SSDs");