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 rrpc_ppa_to_gaddr(struct nvm_dev *dev, u64 addr)
128 struct ppa_addr paddr;
131 return __linear_to_generic_addr(dev, paddr);
134 /* requires lun->lock taken */
135 static void rrpc_set_lun_cur(struct rrpc_lun *rlun, struct rrpc_block *rblk)
137 struct rrpc *rrpc = rlun->rrpc;
142 spin_lock(&rlun->cur->lock);
143 WARN_ON(!block_is_full(rrpc, rlun->cur));
144 spin_unlock(&rlun->cur->lock);
149 static struct rrpc_block *rrpc_get_blk(struct rrpc *rrpc, struct rrpc_lun *rlun,
152 struct nvm_block *blk;
153 struct rrpc_block *rblk;
155 blk = nvm_get_blk(rrpc->dev, rlun->parent, 0);
159 rblk = &rlun->blocks[blk->id];
162 bitmap_zero(rblk->invalid_pages, rrpc->dev->pgs_per_blk);
164 rblk->nr_invalid_pages = 0;
165 atomic_set(&rblk->data_cmnt_size, 0);
170 static void rrpc_put_blk(struct rrpc *rrpc, struct rrpc_block *rblk)
172 nvm_put_blk(rrpc->dev, rblk->parent);
175 static struct rrpc_lun *get_next_lun(struct rrpc *rrpc)
177 int next = atomic_inc_return(&rrpc->next_lun);
179 return &rrpc->luns[next % rrpc->nr_luns];
182 static void rrpc_gc_kick(struct rrpc *rrpc)
184 struct rrpc_lun *rlun;
187 for (i = 0; i < rrpc->nr_luns; i++) {
188 rlun = &rrpc->luns[i];
189 queue_work(rrpc->krqd_wq, &rlun->ws_gc);
194 * timed GC every interval.
196 static void rrpc_gc_timer(unsigned long data)
198 struct rrpc *rrpc = (struct rrpc *)data;
201 mod_timer(&rrpc->gc_timer, jiffies + msecs_to_jiffies(10));
204 static void rrpc_end_sync_bio(struct bio *bio)
206 struct completion *waiting = bio->bi_private;
209 pr_err("nvm: gc request failed (%u).\n", bio->bi_error);
215 * rrpc_move_valid_pages -- migrate live data off the block
216 * @rrpc: the 'rrpc' structure
217 * @block: the block from which to migrate live pages
220 * GC algorithms may call this function to migrate remaining live
221 * pages off the block prior to erasing it. This function blocks
222 * further execution until the operation is complete.
224 static int rrpc_move_valid_pages(struct rrpc *rrpc, struct rrpc_block *rblk)
226 struct request_queue *q = rrpc->dev->q;
227 struct rrpc_rev_addr *rev;
232 int nr_pgs_per_blk = rrpc->dev->pgs_per_blk;
234 DECLARE_COMPLETION_ONSTACK(wait);
236 if (bitmap_full(rblk->invalid_pages, nr_pgs_per_blk))
239 bio = bio_alloc(GFP_NOIO, 1);
241 pr_err("nvm: could not alloc bio to gc\n");
245 page = mempool_alloc(rrpc->page_pool, GFP_NOIO);
247 while ((slot = find_first_zero_bit(rblk->invalid_pages,
248 nr_pgs_per_blk)) < nr_pgs_per_blk) {
251 phys_addr = (rblk->parent->id * nr_pgs_per_blk) + slot;
254 spin_lock(&rrpc->rev_lock);
255 /* Get logical address from physical to logical table */
256 rev = &rrpc->rev_trans_map[phys_addr - rrpc->poffset];
257 /* already updated by previous regular write */
258 if (rev->addr == ADDR_EMPTY) {
259 spin_unlock(&rrpc->rev_lock);
263 rqd = rrpc_inflight_laddr_acquire(rrpc, rev->addr, 1);
264 if (IS_ERR_OR_NULL(rqd)) {
265 spin_unlock(&rrpc->rev_lock);
270 spin_unlock(&rrpc->rev_lock);
272 /* Perform read to do GC */
273 bio->bi_iter.bi_sector = rrpc_get_sector(rev->addr);
275 bio->bi_private = &wait;
276 bio->bi_end_io = rrpc_end_sync_bio;
278 /* TODO: may fail when EXP_PG_SIZE > PAGE_SIZE */
279 bio_add_pc_page(q, bio, page, RRPC_EXPOSED_PAGE_SIZE, 0);
281 if (rrpc_submit_io(rrpc, bio, rqd, NVM_IOTYPE_GC)) {
282 pr_err("rrpc: gc read failed.\n");
283 rrpc_inflight_laddr_release(rrpc, rqd);
286 wait_for_completion_io(&wait);
289 reinit_completion(&wait);
291 bio->bi_iter.bi_sector = rrpc_get_sector(rev->addr);
293 bio->bi_private = &wait;
294 bio->bi_end_io = rrpc_end_sync_bio;
296 bio_add_pc_page(q, bio, page, RRPC_EXPOSED_PAGE_SIZE, 0);
298 /* turn the command around and write the data back to a new
301 if (rrpc_submit_io(rrpc, bio, rqd, NVM_IOTYPE_GC)) {
302 pr_err("rrpc: gc write failed.\n");
303 rrpc_inflight_laddr_release(rrpc, rqd);
306 wait_for_completion_io(&wait);
308 rrpc_inflight_laddr_release(rrpc, rqd);
314 mempool_free(page, rrpc->page_pool);
317 if (!bitmap_full(rblk->invalid_pages, nr_pgs_per_blk)) {
318 pr_err("nvm: failed to garbage collect block\n");
325 static void rrpc_block_gc(struct work_struct *work)
327 struct rrpc_block_gc *gcb = container_of(work, struct rrpc_block_gc,
329 struct rrpc *rrpc = gcb->rrpc;
330 struct rrpc_block *rblk = gcb->rblk;
331 struct nvm_dev *dev = rrpc->dev;
333 pr_debug("nvm: block '%lu' being reclaimed\n", rblk->parent->id);
335 if (rrpc_move_valid_pages(rrpc, rblk))
338 nvm_erase_blk(dev, rblk->parent);
339 rrpc_put_blk(rrpc, rblk);
341 mempool_free(gcb, rrpc->gcb_pool);
344 /* the block with highest number of invalid pages, will be in the beginning
347 static struct rrpc_block *rblock_max_invalid(struct rrpc_block *ra,
348 struct rrpc_block *rb)
350 if (ra->nr_invalid_pages == rb->nr_invalid_pages)
353 return (ra->nr_invalid_pages < rb->nr_invalid_pages) ? rb : ra;
356 /* linearly find the block with highest number of invalid pages
359 static struct rrpc_block *block_prio_find_max(struct rrpc_lun *rlun)
361 struct list_head *prio_list = &rlun->prio_list;
362 struct rrpc_block *rblock, *max;
364 BUG_ON(list_empty(prio_list));
366 max = list_first_entry(prio_list, struct rrpc_block, prio);
367 list_for_each_entry(rblock, prio_list, prio)
368 max = rblock_max_invalid(max, rblock);
373 static void rrpc_lun_gc(struct work_struct *work)
375 struct rrpc_lun *rlun = container_of(work, struct rrpc_lun, ws_gc);
376 struct rrpc *rrpc = rlun->rrpc;
377 struct nvm_lun *lun = rlun->parent;
378 struct rrpc_block_gc *gcb;
379 unsigned int nr_blocks_need;
381 nr_blocks_need = rrpc->dev->blks_per_lun / GC_LIMIT_INVERSE;
383 if (nr_blocks_need < rrpc->nr_luns)
384 nr_blocks_need = rrpc->nr_luns;
386 spin_lock(&lun->lock);
387 while (nr_blocks_need > lun->nr_free_blocks &&
388 !list_empty(&rlun->prio_list)) {
389 struct rrpc_block *rblock = block_prio_find_max(rlun);
390 struct nvm_block *block = rblock->parent;
392 if (!rblock->nr_invalid_pages)
395 list_del_init(&rblock->prio);
397 BUG_ON(!block_is_full(rrpc, rblock));
399 pr_debug("rrpc: selected block '%lu' for GC\n", block->id);
401 gcb = mempool_alloc(rrpc->gcb_pool, GFP_ATOMIC);
407 INIT_WORK(&gcb->ws_gc, rrpc_block_gc);
409 queue_work(rrpc->kgc_wq, &gcb->ws_gc);
413 spin_unlock(&lun->lock);
415 /* TODO: Hint that request queue can be started again */
418 static void rrpc_gc_queue(struct work_struct *work)
420 struct rrpc_block_gc *gcb = container_of(work, struct rrpc_block_gc,
422 struct rrpc *rrpc = gcb->rrpc;
423 struct rrpc_block *rblk = gcb->rblk;
424 struct nvm_lun *lun = rblk->parent->lun;
425 struct rrpc_lun *rlun = &rrpc->luns[lun->id - rrpc->lun_offset];
427 spin_lock(&rlun->lock);
428 list_add_tail(&rblk->prio, &rlun->prio_list);
429 spin_unlock(&rlun->lock);
431 mempool_free(gcb, rrpc->gcb_pool);
432 pr_debug("nvm: block '%lu' is full, allow GC (sched)\n",
436 static const struct block_device_operations rrpc_fops = {
437 .owner = THIS_MODULE,
440 static struct rrpc_lun *rrpc_get_lun_rr(struct rrpc *rrpc, int is_gc)
443 struct rrpc_lun *rlun, *max_free;
446 return get_next_lun(rrpc);
448 /* during GC, we don't care about RR, instead we want to make
449 * sure that we maintain evenness between the block luns.
451 max_free = &rrpc->luns[0];
452 /* prevent GC-ing lun from devouring pages of a lun with
453 * little free blocks. We don't take the lock as we only need an
456 rrpc_for_each_lun(rrpc, rlun, i) {
457 if (rlun->parent->nr_free_blocks >
458 max_free->parent->nr_free_blocks)
465 static struct rrpc_addr *rrpc_update_map(struct rrpc *rrpc, sector_t laddr,
466 struct rrpc_block *rblk, u64 paddr)
468 struct rrpc_addr *gp;
469 struct rrpc_rev_addr *rev;
471 BUG_ON(laddr >= rrpc->nr_pages);
473 gp = &rrpc->trans_map[laddr];
474 spin_lock(&rrpc->rev_lock);
476 rrpc_page_invalidate(rrpc, gp);
481 rev = &rrpc->rev_trans_map[gp->addr - rrpc->poffset];
483 spin_unlock(&rrpc->rev_lock);
488 static u64 rrpc_alloc_addr(struct rrpc *rrpc, struct rrpc_block *rblk)
490 u64 addr = ADDR_EMPTY;
492 spin_lock(&rblk->lock);
493 if (block_is_full(rrpc, rblk))
496 addr = block_to_addr(rrpc, rblk) + rblk->next_page;
500 spin_unlock(&rblk->lock);
504 /* Simple round-robin Logical to physical address translation.
506 * Retrieve the mapping using the active append point. Then update the ap for
507 * the next write to the disk.
509 * Returns rrpc_addr with the physical address and block. Remember to return to
510 * rrpc->addr_cache when request is finished.
512 static struct rrpc_addr *rrpc_map_page(struct rrpc *rrpc, sector_t laddr,
515 struct rrpc_lun *rlun;
516 struct rrpc_block *rblk;
520 rlun = rrpc_get_lun_rr(rrpc, is_gc);
523 if (!is_gc && lun->nr_free_blocks < rrpc->nr_luns * 4)
526 spin_lock(&rlun->lock);
530 paddr = rrpc_alloc_addr(rrpc, rblk);
532 if (paddr == ADDR_EMPTY) {
533 rblk = rrpc_get_blk(rrpc, rlun, 0);
535 rrpc_set_lun_cur(rlun, rblk);
540 /* retry from emergency gc block */
541 paddr = rrpc_alloc_addr(rrpc, rlun->gc_cur);
542 if (paddr == ADDR_EMPTY) {
543 rblk = rrpc_get_blk(rrpc, rlun, 1);
545 pr_err("rrpc: no more blocks");
550 paddr = rrpc_alloc_addr(rrpc, rlun->gc_cur);
556 spin_unlock(&rlun->lock);
557 return rrpc_update_map(rrpc, laddr, rblk, paddr);
559 spin_unlock(&rlun->lock);
563 static void rrpc_run_gc(struct rrpc *rrpc, struct rrpc_block *rblk)
565 struct rrpc_block_gc *gcb;
567 gcb = mempool_alloc(rrpc->gcb_pool, GFP_ATOMIC);
569 pr_err("rrpc: unable to queue block for gc.");
576 INIT_WORK(&gcb->ws_gc, rrpc_gc_queue);
577 queue_work(rrpc->kgc_wq, &gcb->ws_gc);
580 static void rrpc_end_io_write(struct rrpc *rrpc, struct rrpc_rq *rrqd,
581 sector_t laddr, uint8_t npages)
584 struct rrpc_block *rblk;
588 for (i = 0; i < npages; i++) {
589 p = &rrpc->trans_map[laddr + i];
591 lun = rblk->parent->lun;
593 cmnt_size = atomic_inc_return(&rblk->data_cmnt_size);
594 if (unlikely(cmnt_size == rrpc->dev->pgs_per_blk))
595 rrpc_run_gc(rrpc, rblk);
599 static int rrpc_end_io(struct nvm_rq *rqd, int error)
601 struct rrpc *rrpc = container_of(rqd->ins, struct rrpc, instance);
602 struct rrpc_rq *rrqd = nvm_rq_to_pdu(rqd);
603 uint8_t npages = rqd->nr_pages;
604 sector_t laddr = rrpc_get_laddr(rqd->bio) - npages;
606 if (bio_data_dir(rqd->bio) == WRITE)
607 rrpc_end_io_write(rrpc, rrqd, laddr, npages);
609 if (rrqd->flags & NVM_IOTYPE_GC)
612 rrpc_unlock_rq(rrpc, rqd);
616 nvm_dev_dma_free(rrpc->dev, rqd->ppa_list, rqd->dma_ppa_list);
618 nvm_dev_dma_free(rrpc->dev, rqd->metadata, rqd->dma_metadata);
620 mempool_free(rqd, rrpc->rq_pool);
625 static int rrpc_read_ppalist_rq(struct rrpc *rrpc, struct bio *bio,
626 struct nvm_rq *rqd, unsigned long flags, int npages)
628 struct rrpc_inflight_rq *r = rrpc_get_inflight_rq(rqd);
629 struct rrpc_addr *gp;
630 sector_t laddr = rrpc_get_laddr(bio);
631 int is_gc = flags & NVM_IOTYPE_GC;
634 if (!is_gc && rrpc_lock_rq(rrpc, bio, rqd)) {
635 nvm_dev_dma_free(rrpc->dev, rqd->ppa_list, rqd->dma_ppa_list);
636 return NVM_IO_REQUEUE;
639 for (i = 0; i < npages; i++) {
640 /* We assume that mapping occurs at 4KB granularity */
641 BUG_ON(!(laddr + i >= 0 && laddr + i < rrpc->nr_pages));
642 gp = &rrpc->trans_map[laddr + i];
645 rqd->ppa_list[i] = rrpc_ppa_to_gaddr(rrpc->dev,
649 rrpc_unlock_laddr(rrpc, r);
650 nvm_dev_dma_free(rrpc->dev, rqd->ppa_list,
656 rqd->opcode = NVM_OP_HBREAD;
661 static int rrpc_read_rq(struct rrpc *rrpc, struct bio *bio, struct nvm_rq *rqd,
664 struct rrpc_rq *rrqd = nvm_rq_to_pdu(rqd);
665 int is_gc = flags & NVM_IOTYPE_GC;
666 sector_t laddr = rrpc_get_laddr(bio);
667 struct rrpc_addr *gp;
669 if (!is_gc && rrpc_lock_rq(rrpc, bio, rqd))
670 return NVM_IO_REQUEUE;
672 BUG_ON(!(laddr >= 0 && laddr < rrpc->nr_pages));
673 gp = &rrpc->trans_map[laddr];
676 rqd->ppa_addr = rrpc_ppa_to_gaddr(rrpc->dev, gp->addr);
679 rrpc_unlock_rq(rrpc, rqd);
683 rqd->opcode = NVM_OP_HBREAD;
689 static int rrpc_write_ppalist_rq(struct rrpc *rrpc, struct bio *bio,
690 struct nvm_rq *rqd, unsigned long flags, int npages)
692 struct rrpc_inflight_rq *r = rrpc_get_inflight_rq(rqd);
694 sector_t laddr = rrpc_get_laddr(bio);
695 int is_gc = flags & NVM_IOTYPE_GC;
698 if (!is_gc && rrpc_lock_rq(rrpc, bio, rqd)) {
699 nvm_dev_dma_free(rrpc->dev, rqd->ppa_list, rqd->dma_ppa_list);
700 return NVM_IO_REQUEUE;
703 for (i = 0; i < npages; i++) {
704 /* We assume that mapping occurs at 4KB granularity */
705 p = rrpc_map_page(rrpc, laddr + i, is_gc);
708 rrpc_unlock_laddr(rrpc, r);
709 nvm_dev_dma_free(rrpc->dev, rqd->ppa_list,
712 return NVM_IO_REQUEUE;
715 rqd->ppa_list[i] = rrpc_ppa_to_gaddr(rrpc->dev,
719 rqd->opcode = NVM_OP_HBWRITE;
724 static int rrpc_write_rq(struct rrpc *rrpc, struct bio *bio,
725 struct nvm_rq *rqd, unsigned long flags)
727 struct rrpc_rq *rrqd = nvm_rq_to_pdu(rqd);
729 int is_gc = flags & NVM_IOTYPE_GC;
730 sector_t laddr = rrpc_get_laddr(bio);
732 if (!is_gc && rrpc_lock_rq(rrpc, bio, rqd))
733 return NVM_IO_REQUEUE;
735 p = rrpc_map_page(rrpc, laddr, is_gc);
738 rrpc_unlock_rq(rrpc, rqd);
740 return NVM_IO_REQUEUE;
743 rqd->ppa_addr = rrpc_ppa_to_gaddr(rrpc->dev, p->addr);
744 rqd->opcode = NVM_OP_HBWRITE;
750 static int rrpc_setup_rq(struct rrpc *rrpc, struct bio *bio,
751 struct nvm_rq *rqd, unsigned long flags, uint8_t npages)
754 rqd->ppa_list = nvm_dev_dma_alloc(rrpc->dev, GFP_KERNEL,
756 if (!rqd->ppa_list) {
757 pr_err("rrpc: not able to allocate ppa list\n");
761 if (bio_rw(bio) == WRITE)
762 return rrpc_write_ppalist_rq(rrpc, bio, rqd, flags,
765 return rrpc_read_ppalist_rq(rrpc, bio, rqd, flags, npages);
768 if (bio_rw(bio) == WRITE)
769 return rrpc_write_rq(rrpc, bio, rqd, flags);
771 return rrpc_read_rq(rrpc, bio, rqd, flags);
774 static int rrpc_submit_io(struct rrpc *rrpc, struct bio *bio,
775 struct nvm_rq *rqd, unsigned long flags)
778 struct rrpc_rq *rrq = nvm_rq_to_pdu(rqd);
779 uint8_t nr_pages = rrpc_get_pages(bio);
780 int bio_size = bio_sectors(bio) << 9;
782 if (bio_size < rrpc->dev->sec_size)
784 else if (bio_size > rrpc->dev->max_rq_size)
787 err = rrpc_setup_rq(rrpc, bio, rqd, flags, nr_pages);
793 rqd->ins = &rrpc->instance;
794 rqd->nr_pages = nr_pages;
797 err = nvm_submit_io(rrpc->dev, rqd);
799 pr_err("rrpc: I/O submission failed: %d\n", err);
806 static blk_qc_t rrpc_make_rq(struct request_queue *q, struct bio *bio)
808 struct rrpc *rrpc = q->queuedata;
812 if (bio->bi_rw & REQ_DISCARD) {
813 rrpc_discard(rrpc, bio);
814 return BLK_QC_T_NONE;
817 rqd = mempool_alloc(rrpc->rq_pool, GFP_KERNEL);
819 pr_err_ratelimited("rrpc: not able to queue bio.");
821 return BLK_QC_T_NONE;
823 memset(rqd, 0, sizeof(struct nvm_rq));
825 err = rrpc_submit_io(rrpc, bio, rqd, NVM_IOTYPE_NONE);
828 return BLK_QC_T_NONE;
836 spin_lock(&rrpc->bio_lock);
837 bio_list_add(&rrpc->requeue_bios, bio);
838 spin_unlock(&rrpc->bio_lock);
839 queue_work(rrpc->kgc_wq, &rrpc->ws_requeue);
843 mempool_free(rqd, rrpc->rq_pool);
844 return BLK_QC_T_NONE;
847 static void rrpc_requeue(struct work_struct *work)
849 struct rrpc *rrpc = container_of(work, struct rrpc, ws_requeue);
850 struct bio_list bios;
853 bio_list_init(&bios);
855 spin_lock(&rrpc->bio_lock);
856 bio_list_merge(&bios, &rrpc->requeue_bios);
857 bio_list_init(&rrpc->requeue_bios);
858 spin_unlock(&rrpc->bio_lock);
860 while ((bio = bio_list_pop(&bios)))
861 rrpc_make_rq(rrpc->disk->queue, bio);
864 static void rrpc_gc_free(struct rrpc *rrpc)
866 struct rrpc_lun *rlun;
870 destroy_workqueue(rrpc->krqd_wq);
873 destroy_workqueue(rrpc->kgc_wq);
878 for (i = 0; i < rrpc->nr_luns; i++) {
879 rlun = &rrpc->luns[i];
887 static int rrpc_gc_init(struct rrpc *rrpc)
889 rrpc->krqd_wq = alloc_workqueue("rrpc-lun", WQ_MEM_RECLAIM|WQ_UNBOUND,
894 rrpc->kgc_wq = alloc_workqueue("rrpc-bg", WQ_MEM_RECLAIM, 1);
898 setup_timer(&rrpc->gc_timer, rrpc_gc_timer, (unsigned long)rrpc);
903 static void rrpc_map_free(struct rrpc *rrpc)
905 vfree(rrpc->rev_trans_map);
906 vfree(rrpc->trans_map);
909 static int rrpc_l2p_update(u64 slba, u32 nlb, __le64 *entries, void *private)
911 struct rrpc *rrpc = (struct rrpc *)private;
912 struct nvm_dev *dev = rrpc->dev;
913 struct rrpc_addr *addr = rrpc->trans_map + slba;
914 struct rrpc_rev_addr *raddr = rrpc->rev_trans_map;
915 sector_t max_pages = dev->total_pages * (dev->sec_size >> 9);
916 u64 elba = slba + nlb;
919 if (unlikely(elba > dev->total_pages)) {
920 pr_err("nvm: L2P data from device is out of bounds!\n");
924 for (i = 0; i < nlb; i++) {
925 u64 pba = le64_to_cpu(entries[i]);
926 /* LNVM treats address-spaces as silos, LBA and PBA are
927 * equally large and zero-indexed.
929 if (unlikely(pba >= max_pages && pba != U64_MAX)) {
930 pr_err("nvm: L2P data entry is out of bounds!\n");
934 /* Address zero is a special one. The first page on a disk is
935 * protected. As it often holds internal device boot
942 raddr[pba].addr = slba + i;
948 static int rrpc_map_init(struct rrpc *rrpc)
950 struct nvm_dev *dev = rrpc->dev;
954 rrpc->trans_map = vzalloc(sizeof(struct rrpc_addr) * rrpc->nr_pages);
955 if (!rrpc->trans_map)
958 rrpc->rev_trans_map = vmalloc(sizeof(struct rrpc_rev_addr)
960 if (!rrpc->rev_trans_map)
963 for (i = 0; i < rrpc->nr_pages; i++) {
964 struct rrpc_addr *p = &rrpc->trans_map[i];
965 struct rrpc_rev_addr *r = &rrpc->rev_trans_map[i];
967 p->addr = ADDR_EMPTY;
968 r->addr = ADDR_EMPTY;
971 if (!dev->ops->get_l2p_tbl)
974 /* Bring up the mapping table from device */
975 ret = dev->ops->get_l2p_tbl(dev->q, 0, dev->total_pages,
976 rrpc_l2p_update, rrpc);
978 pr_err("nvm: rrpc: could not read L2P table.\n");
986 /* Minimum pages needed within a lun */
987 #define PAGE_POOL_SIZE 16
988 #define ADDR_POOL_SIZE 64
990 static int rrpc_core_init(struct rrpc *rrpc)
992 down_write(&rrpc_lock);
993 if (!rrpc_gcb_cache) {
994 rrpc_gcb_cache = kmem_cache_create("rrpc_gcb",
995 sizeof(struct rrpc_block_gc), 0, 0, NULL);
996 if (!rrpc_gcb_cache) {
997 up_write(&rrpc_lock);
1001 rrpc_rq_cache = kmem_cache_create("rrpc_rq",
1002 sizeof(struct nvm_rq) + sizeof(struct rrpc_rq),
1004 if (!rrpc_rq_cache) {
1005 kmem_cache_destroy(rrpc_gcb_cache);
1006 up_write(&rrpc_lock);
1010 up_write(&rrpc_lock);
1012 rrpc->page_pool = mempool_create_page_pool(PAGE_POOL_SIZE, 0);
1013 if (!rrpc->page_pool)
1016 rrpc->gcb_pool = mempool_create_slab_pool(rrpc->dev->nr_luns,
1018 if (!rrpc->gcb_pool)
1021 rrpc->rq_pool = mempool_create_slab_pool(64, rrpc_rq_cache);
1025 spin_lock_init(&rrpc->inflights.lock);
1026 INIT_LIST_HEAD(&rrpc->inflights.reqs);
1031 static void rrpc_core_free(struct rrpc *rrpc)
1033 mempool_destroy(rrpc->page_pool);
1034 mempool_destroy(rrpc->gcb_pool);
1035 mempool_destroy(rrpc->rq_pool);
1038 static void rrpc_luns_free(struct rrpc *rrpc)
1043 static int rrpc_luns_init(struct rrpc *rrpc, int lun_begin, int lun_end)
1045 struct nvm_dev *dev = rrpc->dev;
1046 struct rrpc_lun *rlun;
1049 spin_lock_init(&rrpc->rev_lock);
1051 rrpc->luns = kcalloc(rrpc->nr_luns, sizeof(struct rrpc_lun),
1057 for (i = 0; i < rrpc->nr_luns; i++) {
1058 struct nvm_lun *lun = dev->mt->get_lun(dev, lun_begin + i);
1060 if (dev->pgs_per_blk >
1061 MAX_INVALID_PAGES_STORAGE * BITS_PER_LONG) {
1062 pr_err("rrpc: number of pages per block too high.");
1066 rlun = &rrpc->luns[i];
1069 INIT_LIST_HEAD(&rlun->prio_list);
1070 INIT_WORK(&rlun->ws_gc, rrpc_lun_gc);
1071 spin_lock_init(&rlun->lock);
1073 rrpc->total_blocks += dev->blks_per_lun;
1074 rrpc->nr_pages += dev->sec_per_lun;
1076 rlun->blocks = vzalloc(sizeof(struct rrpc_block) *
1077 rrpc->dev->blks_per_lun);
1081 for (j = 0; j < rrpc->dev->blks_per_lun; j++) {
1082 struct rrpc_block *rblk = &rlun->blocks[j];
1083 struct nvm_block *blk = &lun->blocks[j];
1086 INIT_LIST_HEAD(&rblk->prio);
1087 spin_lock_init(&rblk->lock);
1096 static void rrpc_free(struct rrpc *rrpc)
1099 rrpc_map_free(rrpc);
1100 rrpc_core_free(rrpc);
1101 rrpc_luns_free(rrpc);
1106 static void rrpc_exit(void *private)
1108 struct rrpc *rrpc = private;
1110 del_timer(&rrpc->gc_timer);
1112 flush_workqueue(rrpc->krqd_wq);
1113 flush_workqueue(rrpc->kgc_wq);
1118 static sector_t rrpc_capacity(void *private)
1120 struct rrpc *rrpc = private;
1121 struct nvm_dev *dev = rrpc->dev;
1122 sector_t reserved, provisioned;
1124 /* cur, gc, and two emergency blocks for each lun */
1125 reserved = rrpc->nr_luns * dev->max_pages_per_blk * 4;
1126 provisioned = rrpc->nr_pages - reserved;
1128 if (reserved > rrpc->nr_pages) {
1129 pr_err("rrpc: not enough space available to expose storage.\n");
1133 sector_div(provisioned, 10);
1134 return provisioned * 9 * NR_PHY_IN_LOG;
1138 * Looks up the logical address from reverse trans map and check if its valid by
1139 * comparing the logical to physical address with the physical address.
1140 * Returns 0 on free, otherwise 1 if in use
1142 static void rrpc_block_map_update(struct rrpc *rrpc, struct rrpc_block *rblk)
1144 struct nvm_dev *dev = rrpc->dev;
1146 struct rrpc_addr *laddr;
1149 for (offset = 0; offset < dev->pgs_per_blk; offset++) {
1150 paddr = block_to_addr(rrpc, rblk) + offset;
1152 pladdr = rrpc->rev_trans_map[paddr].addr;
1153 if (pladdr == ADDR_EMPTY)
1156 laddr = &rrpc->trans_map[pladdr];
1158 if (paddr == laddr->addr) {
1161 set_bit(offset, rblk->invalid_pages);
1162 rblk->nr_invalid_pages++;
1167 static int rrpc_blocks_init(struct rrpc *rrpc)
1169 struct rrpc_lun *rlun;
1170 struct rrpc_block *rblk;
1171 int lun_iter, blk_iter;
1173 for (lun_iter = 0; lun_iter < rrpc->nr_luns; lun_iter++) {
1174 rlun = &rrpc->luns[lun_iter];
1176 for (blk_iter = 0; blk_iter < rrpc->dev->blks_per_lun;
1178 rblk = &rlun->blocks[blk_iter];
1179 rrpc_block_map_update(rrpc, rblk);
1186 static int rrpc_luns_configure(struct rrpc *rrpc)
1188 struct rrpc_lun *rlun;
1189 struct rrpc_block *rblk;
1192 for (i = 0; i < rrpc->nr_luns; i++) {
1193 rlun = &rrpc->luns[i];
1195 rblk = rrpc_get_blk(rrpc, rlun, 0);
1199 rrpc_set_lun_cur(rlun, rblk);
1201 /* Emergency gc block */
1202 rblk = rrpc_get_blk(rrpc, rlun, 1);
1205 rlun->gc_cur = rblk;
1211 static struct nvm_tgt_type tt_rrpc;
1213 static void *rrpc_init(struct nvm_dev *dev, struct gendisk *tdisk,
1214 int lun_begin, int lun_end)
1216 struct request_queue *bqueue = dev->q;
1217 struct request_queue *tqueue = tdisk->queue;
1221 if (!(dev->identity.dom & NVM_RSP_L2P)) {
1222 pr_err("nvm: rrpc: device does not support l2p (%x)\n",
1224 return ERR_PTR(-EINVAL);
1227 rrpc = kzalloc(sizeof(struct rrpc), GFP_KERNEL);
1229 return ERR_PTR(-ENOMEM);
1231 rrpc->instance.tt = &tt_rrpc;
1235 bio_list_init(&rrpc->requeue_bios);
1236 spin_lock_init(&rrpc->bio_lock);
1237 INIT_WORK(&rrpc->ws_requeue, rrpc_requeue);
1239 rrpc->nr_luns = lun_end - lun_begin + 1;
1241 /* simple round-robin strategy */
1242 atomic_set(&rrpc->next_lun, -1);
1244 ret = rrpc_luns_init(rrpc, lun_begin, lun_end);
1246 pr_err("nvm: rrpc: could not initialize luns\n");
1250 rrpc->poffset = dev->sec_per_lun * lun_begin;
1251 rrpc->lun_offset = lun_begin;
1253 ret = rrpc_core_init(rrpc);
1255 pr_err("nvm: rrpc: could not initialize core\n");
1259 ret = rrpc_map_init(rrpc);
1261 pr_err("nvm: rrpc: could not initialize maps\n");
1265 ret = rrpc_blocks_init(rrpc);
1267 pr_err("nvm: rrpc: could not initialize state for blocks\n");
1271 ret = rrpc_luns_configure(rrpc);
1273 pr_err("nvm: rrpc: not enough blocks available in LUNs.\n");
1277 ret = rrpc_gc_init(rrpc);
1279 pr_err("nvm: rrpc: could not initialize gc\n");
1283 /* inherit the size from the underlying device */
1284 blk_queue_logical_block_size(tqueue, queue_physical_block_size(bqueue));
1285 blk_queue_max_hw_sectors(tqueue, queue_max_hw_sectors(bqueue));
1287 pr_info("nvm: rrpc initialized with %u luns and %llu pages.\n",
1288 rrpc->nr_luns, (unsigned long long)rrpc->nr_pages);
1290 mod_timer(&rrpc->gc_timer, jiffies + msecs_to_jiffies(10));
1295 return ERR_PTR(ret);
1298 /* round robin, page-based FTL, and cost-based GC */
1299 static struct nvm_tgt_type tt_rrpc = {
1301 .version = {1, 0, 0},
1303 .make_rq = rrpc_make_rq,
1304 .capacity = rrpc_capacity,
1305 .end_io = rrpc_end_io,
1311 static int __init rrpc_module_init(void)
1313 return nvm_register_target(&tt_rrpc);
1316 static void rrpc_module_exit(void)
1318 nvm_unregister_target(&tt_rrpc);
1321 module_init(rrpc_module_init);
1322 module_exit(rrpc_module_exit);
1323 MODULE_LICENSE("GPL v2");
1324 MODULE_DESCRIPTION("Block-Device Target for Open-Channel SSDs");