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
->sec_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
);
108 pr_err("rrpc: unable to acquire inflight IO\n");
113 rrpc_invalidate_range(rrpc
, slba
, len
);
114 rrpc_inflight_laddr_release(rrpc
, rqd
);
117 static int block_is_full(struct rrpc
*rrpc
, struct rrpc_block
*rblk
)
119 return (rblk
->next_page
== rrpc
->dev
->sec_per_blk
);
122 /* Calculate relative addr for the given block, considering instantiated LUNs */
123 static u64
block_to_rel_addr(struct rrpc
*rrpc
, struct rrpc_block
*rblk
)
125 struct nvm_block
*blk
= rblk
->parent
;
126 int lun_blk
= blk
->id
% (rrpc
->dev
->blks_per_lun
* rrpc
->nr_luns
);
128 return lun_blk
* rrpc
->dev
->sec_per_blk
;
131 /* Calculate global addr for the given block */
132 static u64
block_to_addr(struct rrpc
*rrpc
, struct rrpc_block
*rblk
)
134 struct nvm_block
*blk
= rblk
->parent
;
136 return blk
->id
* rrpc
->dev
->sec_per_blk
;
139 static struct ppa_addr
linear_to_generic_addr(struct nvm_dev
*dev
,
143 int secs
, pgs
, blks
, luns
;
144 sector_t ppa
= r
.ppa
;
148 div_u64_rem(ppa
, dev
->sec_per_pg
, &secs
);
151 sector_div(ppa
, dev
->sec_per_pg
);
152 div_u64_rem(ppa
, dev
->pgs_per_blk
, &pgs
);
155 sector_div(ppa
, dev
->pgs_per_blk
);
156 div_u64_rem(ppa
, dev
->blks_per_lun
, &blks
);
159 sector_div(ppa
, dev
->blks_per_lun
);
160 div_u64_rem(ppa
, dev
->luns_per_chnl
, &luns
);
163 sector_div(ppa
, dev
->luns_per_chnl
);
169 static struct ppa_addr
rrpc_ppa_to_gaddr(struct nvm_dev
*dev
, u64 addr
)
171 struct ppa_addr paddr
;
174 return linear_to_generic_addr(dev
, paddr
);
177 /* requires lun->lock taken */
178 static void rrpc_set_lun_cur(struct rrpc_lun
*rlun
, struct rrpc_block
*rblk
)
180 struct rrpc
*rrpc
= rlun
->rrpc
;
185 spin_lock(&rlun
->cur
->lock
);
186 WARN_ON(!block_is_full(rrpc
, rlun
->cur
));
187 spin_unlock(&rlun
->cur
->lock
);
192 static struct rrpc_block
*rrpc_get_blk(struct rrpc
*rrpc
, struct rrpc_lun
*rlun
,
195 struct nvm_block
*blk
;
196 struct rrpc_block
*rblk
;
198 blk
= nvm_get_blk(rrpc
->dev
, rlun
->parent
, flags
);
200 pr_err("nvm: rrpc: cannot get new block from media manager\n");
204 rblk
= rrpc_get_rblk(rlun
, blk
->id
);
206 bitmap_zero(rblk
->invalid_pages
, rrpc
->dev
->sec_per_blk
);
208 rblk
->nr_invalid_pages
= 0;
209 atomic_set(&rblk
->data_cmnt_size
, 0);
214 static void rrpc_put_blk(struct rrpc
*rrpc
, struct rrpc_block
*rblk
)
216 nvm_put_blk(rrpc
->dev
, rblk
->parent
);
219 static void rrpc_put_blks(struct rrpc
*rrpc
)
221 struct rrpc_lun
*rlun
;
224 for (i
= 0; i
< rrpc
->nr_luns
; i
++) {
225 rlun
= &rrpc
->luns
[i
];
227 rrpc_put_blk(rrpc
, rlun
->cur
);
229 rrpc_put_blk(rrpc
, rlun
->gc_cur
);
233 static struct rrpc_lun
*get_next_lun(struct rrpc
*rrpc
)
235 int next
= atomic_inc_return(&rrpc
->next_lun
);
237 return &rrpc
->luns
[next
% rrpc
->nr_luns
];
240 static void rrpc_gc_kick(struct rrpc
*rrpc
)
242 struct rrpc_lun
*rlun
;
245 for (i
= 0; i
< rrpc
->nr_luns
; i
++) {
246 rlun
= &rrpc
->luns
[i
];
247 queue_work(rrpc
->krqd_wq
, &rlun
->ws_gc
);
252 * timed GC every interval.
254 static void rrpc_gc_timer(unsigned long data
)
256 struct rrpc
*rrpc
= (struct rrpc
*)data
;
259 mod_timer(&rrpc
->gc_timer
, jiffies
+ msecs_to_jiffies(10));
262 static void rrpc_end_sync_bio(struct bio
*bio
)
264 struct completion
*waiting
= bio
->bi_private
;
267 pr_err("nvm: gc request failed (%u).\n", bio
->bi_error
);
273 * rrpc_move_valid_pages -- migrate live data off the block
274 * @rrpc: the 'rrpc' structure
275 * @block: the block from which to migrate live pages
278 * GC algorithms may call this function to migrate remaining live
279 * pages off the block prior to erasing it. This function blocks
280 * further execution until the operation is complete.
282 static int rrpc_move_valid_pages(struct rrpc
*rrpc
, struct rrpc_block
*rblk
)
284 struct request_queue
*q
= rrpc
->dev
->q
;
285 struct rrpc_rev_addr
*rev
;
290 int nr_sec_per_blk
= rrpc
->dev
->sec_per_blk
;
292 DECLARE_COMPLETION_ONSTACK(wait
);
294 if (bitmap_full(rblk
->invalid_pages
, nr_sec_per_blk
))
297 bio
= bio_alloc(GFP_NOIO
, 1);
299 pr_err("nvm: could not alloc bio to gc\n");
303 page
= mempool_alloc(rrpc
->page_pool
, GFP_NOIO
);
309 while ((slot
= find_first_zero_bit(rblk
->invalid_pages
,
310 nr_sec_per_blk
)) < nr_sec_per_blk
) {
313 phys_addr
= rblk
->parent
->id
* nr_sec_per_blk
+ slot
;
316 spin_lock(&rrpc
->rev_lock
);
317 /* Get logical address from physical to logical table */
318 rev
= &rrpc
->rev_trans_map
[phys_addr
- rrpc
->poffset
];
319 /* already updated by previous regular write */
320 if (rev
->addr
== ADDR_EMPTY
) {
321 spin_unlock(&rrpc
->rev_lock
);
325 rqd
= rrpc_inflight_laddr_acquire(rrpc
, rev
->addr
, 1);
326 if (IS_ERR_OR_NULL(rqd
)) {
327 spin_unlock(&rrpc
->rev_lock
);
332 spin_unlock(&rrpc
->rev_lock
);
334 /* Perform read to do GC */
335 bio
->bi_iter
.bi_sector
= rrpc_get_sector(rev
->addr
);
336 bio_set_op_attrs(bio
, REQ_OP_READ
, 0);
337 bio
->bi_private
= &wait
;
338 bio
->bi_end_io
= rrpc_end_sync_bio
;
340 /* TODO: may fail when EXP_PG_SIZE > PAGE_SIZE */
341 bio_add_pc_page(q
, bio
, page
, RRPC_EXPOSED_PAGE_SIZE
, 0);
343 if (rrpc_submit_io(rrpc
, bio
, rqd
, NVM_IOTYPE_GC
)) {
344 pr_err("rrpc: gc read failed.\n");
345 rrpc_inflight_laddr_release(rrpc
, rqd
);
348 wait_for_completion_io(&wait
);
350 rrpc_inflight_laddr_release(rrpc
, rqd
);
355 reinit_completion(&wait
);
357 bio
->bi_iter
.bi_sector
= rrpc_get_sector(rev
->addr
);
358 bio_set_op_attrs(bio
, REQ_OP_WRITE
, 0);
359 bio
->bi_private
= &wait
;
360 bio
->bi_end_io
= rrpc_end_sync_bio
;
362 bio_add_pc_page(q
, bio
, page
, RRPC_EXPOSED_PAGE_SIZE
, 0);
364 /* turn the command around and write the data back to a new
367 if (rrpc_submit_io(rrpc
, bio
, rqd
, NVM_IOTYPE_GC
)) {
368 pr_err("rrpc: gc write failed.\n");
369 rrpc_inflight_laddr_release(rrpc
, rqd
);
372 wait_for_completion_io(&wait
);
374 rrpc_inflight_laddr_release(rrpc
, rqd
);
382 mempool_free(page
, rrpc
->page_pool
);
385 if (!bitmap_full(rblk
->invalid_pages
, nr_sec_per_blk
)) {
386 pr_err("nvm: failed to garbage collect block\n");
393 static void rrpc_block_gc(struct work_struct
*work
)
395 struct rrpc_block_gc
*gcb
= container_of(work
, struct rrpc_block_gc
,
397 struct rrpc
*rrpc
= gcb
->rrpc
;
398 struct rrpc_block
*rblk
= gcb
->rblk
;
399 struct rrpc_lun
*rlun
= rblk
->rlun
;
400 struct nvm_dev
*dev
= rrpc
->dev
;
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 rrpc_lun
*rlun
= rblk
->rlun
;
503 spin_lock(&rlun
->lock
);
504 list_add_tail(&rblk
->prio
, &rlun
->prio_list
);
505 spin_unlock(&rlun
->lock
);
507 mempool_free(gcb
, rrpc
->gcb_pool
);
508 pr_debug("nvm: block '%lu' is full, allow GC (sched)\n",
512 static const struct block_device_operations rrpc_fops
= {
513 .owner
= THIS_MODULE
,
516 static struct rrpc_lun
*rrpc_get_lun_rr(struct rrpc
*rrpc
, int is_gc
)
519 struct rrpc_lun
*rlun
, *max_free
;
522 return get_next_lun(rrpc
);
524 /* during GC, we don't care about RR, instead we want to make
525 * sure that we maintain evenness between the block luns.
527 max_free
= &rrpc
->luns
[0];
528 /* prevent GC-ing lun from devouring pages of a lun with
529 * little free blocks. We don't take the lock as we only need an
532 rrpc_for_each_lun(rrpc
, rlun
, i
) {
533 if (rlun
->parent
->nr_free_blocks
>
534 max_free
->parent
->nr_free_blocks
)
541 static struct rrpc_addr
*rrpc_update_map(struct rrpc
*rrpc
, sector_t laddr
,
542 struct rrpc_block
*rblk
, u64 paddr
)
544 struct rrpc_addr
*gp
;
545 struct rrpc_rev_addr
*rev
;
547 BUG_ON(laddr
>= rrpc
->nr_sects
);
549 gp
= &rrpc
->trans_map
[laddr
];
550 spin_lock(&rrpc
->rev_lock
);
552 rrpc_page_invalidate(rrpc
, gp
);
557 rev
= &rrpc
->rev_trans_map
[gp
->addr
- rrpc
->poffset
];
559 spin_unlock(&rrpc
->rev_lock
);
564 static u64
rrpc_alloc_addr(struct rrpc
*rrpc
, struct rrpc_block
*rblk
)
566 u64 addr
= ADDR_EMPTY
;
568 spin_lock(&rblk
->lock
);
569 if (block_is_full(rrpc
, rblk
))
572 addr
= block_to_addr(rrpc
, rblk
) + rblk
->next_page
;
576 spin_unlock(&rblk
->lock
);
580 /* Simple round-robin Logical to physical address translation.
582 * Retrieve the mapping using the active append point. Then update the ap for
583 * the next write to the disk.
585 * Returns rrpc_addr with the physical address and block. Remember to return to
586 * rrpc->addr_cache when request is finished.
588 static struct rrpc_addr
*rrpc_map_page(struct rrpc
*rrpc
, sector_t laddr
,
591 struct rrpc_lun
*rlun
;
592 struct rrpc_block
*rblk
;
596 rlun
= rrpc_get_lun_rr(rrpc
, is_gc
);
599 if (!is_gc
&& lun
->nr_free_blocks
< rrpc
->nr_luns
* 4)
602 spin_lock(&rlun
->lock
);
606 paddr
= rrpc_alloc_addr(rrpc
, rblk
);
608 if (paddr
== ADDR_EMPTY
) {
609 rblk
= rrpc_get_blk(rrpc
, rlun
, 0);
611 rrpc_set_lun_cur(rlun
, rblk
);
616 /* retry from emergency gc block */
617 paddr
= rrpc_alloc_addr(rrpc
, rlun
->gc_cur
);
618 if (paddr
== ADDR_EMPTY
) {
619 rblk
= rrpc_get_blk(rrpc
, rlun
, 1);
621 pr_err("rrpc: no more blocks");
626 paddr
= rrpc_alloc_addr(rrpc
, rlun
->gc_cur
);
632 spin_unlock(&rlun
->lock
);
633 return rrpc_update_map(rrpc
, laddr
, rblk
, paddr
);
635 spin_unlock(&rlun
->lock
);
639 static void rrpc_run_gc(struct rrpc
*rrpc
, struct rrpc_block
*rblk
)
641 struct rrpc_block_gc
*gcb
;
643 gcb
= mempool_alloc(rrpc
->gcb_pool
, GFP_ATOMIC
);
645 pr_err("rrpc: unable to queue block for gc.");
652 INIT_WORK(&gcb
->ws_gc
, rrpc_gc_queue
);
653 queue_work(rrpc
->kgc_wq
, &gcb
->ws_gc
);
656 static void rrpc_end_io_write(struct rrpc
*rrpc
, struct rrpc_rq
*rrqd
,
657 sector_t laddr
, uint8_t npages
)
660 struct rrpc_block
*rblk
;
664 for (i
= 0; i
< npages
; i
++) {
665 p
= &rrpc
->trans_map
[laddr
+ i
];
667 lun
= rblk
->parent
->lun
;
669 cmnt_size
= atomic_inc_return(&rblk
->data_cmnt_size
);
670 if (unlikely(cmnt_size
== rrpc
->dev
->sec_per_blk
))
671 rrpc_run_gc(rrpc
, rblk
);
675 static void rrpc_end_io(struct nvm_rq
*rqd
)
677 struct rrpc
*rrpc
= container_of(rqd
->ins
, struct rrpc
, instance
);
678 struct rrpc_rq
*rrqd
= nvm_rq_to_pdu(rqd
);
679 uint8_t npages
= rqd
->nr_ppas
;
680 sector_t laddr
= rrpc_get_laddr(rqd
->bio
) - npages
;
682 if (bio_data_dir(rqd
->bio
) == WRITE
)
683 rrpc_end_io_write(rrpc
, rrqd
, laddr
, npages
);
687 if (rrqd
->flags
& NVM_IOTYPE_GC
)
690 rrpc_unlock_rq(rrpc
, rqd
);
693 nvm_dev_dma_free(rrpc
->dev
, rqd
->ppa_list
, rqd
->dma_ppa_list
);
695 mempool_free(rqd
, rrpc
->rq_pool
);
698 static int rrpc_read_ppalist_rq(struct rrpc
*rrpc
, struct bio
*bio
,
699 struct nvm_rq
*rqd
, unsigned long flags
, int npages
)
701 struct rrpc_inflight_rq
*r
= rrpc_get_inflight_rq(rqd
);
702 struct rrpc_addr
*gp
;
703 sector_t laddr
= rrpc_get_laddr(bio
);
704 int is_gc
= flags
& NVM_IOTYPE_GC
;
707 if (!is_gc
&& rrpc_lock_rq(rrpc
, bio
, rqd
)) {
708 nvm_dev_dma_free(rrpc
->dev
, rqd
->ppa_list
, rqd
->dma_ppa_list
);
709 return NVM_IO_REQUEUE
;
712 for (i
= 0; i
< npages
; i
++) {
713 /* We assume that mapping occurs at 4KB granularity */
714 BUG_ON(!(laddr
+ i
>= 0 && laddr
+ i
< rrpc
->nr_sects
));
715 gp
= &rrpc
->trans_map
[laddr
+ i
];
718 rqd
->ppa_list
[i
] = rrpc_ppa_to_gaddr(rrpc
->dev
,
722 rrpc_unlock_laddr(rrpc
, r
);
723 nvm_dev_dma_free(rrpc
->dev
, rqd
->ppa_list
,
729 rqd
->opcode
= NVM_OP_HBREAD
;
734 static int rrpc_read_rq(struct rrpc
*rrpc
, struct bio
*bio
, struct nvm_rq
*rqd
,
737 struct rrpc_rq
*rrqd
= nvm_rq_to_pdu(rqd
);
738 int is_gc
= flags
& NVM_IOTYPE_GC
;
739 sector_t laddr
= rrpc_get_laddr(bio
);
740 struct rrpc_addr
*gp
;
742 if (!is_gc
&& rrpc_lock_rq(rrpc
, bio
, rqd
))
743 return NVM_IO_REQUEUE
;
745 BUG_ON(!(laddr
>= 0 && laddr
< rrpc
->nr_sects
));
746 gp
= &rrpc
->trans_map
[laddr
];
749 rqd
->ppa_addr
= rrpc_ppa_to_gaddr(rrpc
->dev
, gp
->addr
);
752 rrpc_unlock_rq(rrpc
, rqd
);
756 rqd
->opcode
= NVM_OP_HBREAD
;
762 static int rrpc_write_ppalist_rq(struct rrpc
*rrpc
, struct bio
*bio
,
763 struct nvm_rq
*rqd
, unsigned long flags
, int npages
)
765 struct rrpc_inflight_rq
*r
= rrpc_get_inflight_rq(rqd
);
767 sector_t laddr
= rrpc_get_laddr(bio
);
768 int is_gc
= flags
& NVM_IOTYPE_GC
;
771 if (!is_gc
&& rrpc_lock_rq(rrpc
, bio
, rqd
)) {
772 nvm_dev_dma_free(rrpc
->dev
, rqd
->ppa_list
, rqd
->dma_ppa_list
);
773 return NVM_IO_REQUEUE
;
776 for (i
= 0; i
< npages
; i
++) {
777 /* We assume that mapping occurs at 4KB granularity */
778 p
= rrpc_map_page(rrpc
, laddr
+ i
, is_gc
);
781 rrpc_unlock_laddr(rrpc
, r
);
782 nvm_dev_dma_free(rrpc
->dev
, rqd
->ppa_list
,
785 return NVM_IO_REQUEUE
;
788 rqd
->ppa_list
[i
] = rrpc_ppa_to_gaddr(rrpc
->dev
,
792 rqd
->opcode
= NVM_OP_HBWRITE
;
797 static int rrpc_write_rq(struct rrpc
*rrpc
, struct bio
*bio
,
798 struct nvm_rq
*rqd
, unsigned long flags
)
800 struct rrpc_rq
*rrqd
= nvm_rq_to_pdu(rqd
);
802 int is_gc
= flags
& NVM_IOTYPE_GC
;
803 sector_t laddr
= rrpc_get_laddr(bio
);
805 if (!is_gc
&& rrpc_lock_rq(rrpc
, bio
, rqd
))
806 return NVM_IO_REQUEUE
;
808 p
= rrpc_map_page(rrpc
, laddr
, is_gc
);
811 rrpc_unlock_rq(rrpc
, rqd
);
813 return NVM_IO_REQUEUE
;
816 rqd
->ppa_addr
= rrpc_ppa_to_gaddr(rrpc
->dev
, p
->addr
);
817 rqd
->opcode
= NVM_OP_HBWRITE
;
823 static int rrpc_setup_rq(struct rrpc
*rrpc
, struct bio
*bio
,
824 struct nvm_rq
*rqd
, unsigned long flags
, uint8_t npages
)
827 rqd
->ppa_list
= nvm_dev_dma_alloc(rrpc
->dev
, GFP_KERNEL
,
829 if (!rqd
->ppa_list
) {
830 pr_err("rrpc: not able to allocate ppa list\n");
834 if (bio_rw(bio
) == WRITE
)
835 return rrpc_write_ppalist_rq(rrpc
, bio
, rqd
, flags
,
838 return rrpc_read_ppalist_rq(rrpc
, bio
, rqd
, flags
, npages
);
841 if (bio_rw(bio
) == WRITE
)
842 return rrpc_write_rq(rrpc
, bio
, rqd
, flags
);
844 return rrpc_read_rq(rrpc
, bio
, rqd
, flags
);
847 static int rrpc_submit_io(struct rrpc
*rrpc
, struct bio
*bio
,
848 struct nvm_rq
*rqd
, unsigned long flags
)
851 struct rrpc_rq
*rrq
= nvm_rq_to_pdu(rqd
);
852 uint8_t nr_pages
= rrpc_get_pages(bio
);
853 int bio_size
= bio_sectors(bio
) << 9;
855 if (bio_size
< rrpc
->dev
->sec_size
)
857 else if (bio_size
> rrpc
->dev
->max_rq_size
)
860 err
= rrpc_setup_rq(rrpc
, bio
, rqd
, flags
, nr_pages
);
866 rqd
->ins
= &rrpc
->instance
;
867 rqd
->nr_ppas
= nr_pages
;
870 err
= nvm_submit_io(rrpc
->dev
, rqd
);
872 pr_err("rrpc: I/O submission failed: %d\n", err
);
874 if (!(flags
& NVM_IOTYPE_GC
)) {
875 rrpc_unlock_rq(rrpc
, rqd
);
876 if (rqd
->nr_ppas
> 1)
877 nvm_dev_dma_free(rrpc
->dev
,
878 rqd
->ppa_list
, rqd
->dma_ppa_list
);
886 static blk_qc_t
rrpc_make_rq(struct request_queue
*q
, struct bio
*bio
)
888 struct rrpc
*rrpc
= q
->queuedata
;
892 if (bio_op(bio
) == REQ_OP_DISCARD
) {
893 rrpc_discard(rrpc
, bio
);
894 return BLK_QC_T_NONE
;
897 rqd
= mempool_alloc(rrpc
->rq_pool
, GFP_KERNEL
);
899 pr_err_ratelimited("rrpc: not able to queue bio.");
901 return BLK_QC_T_NONE
;
903 memset(rqd
, 0, sizeof(struct nvm_rq
));
905 err
= rrpc_submit_io(rrpc
, bio
, rqd
, NVM_IOTYPE_NONE
);
908 return BLK_QC_T_NONE
;
916 spin_lock(&rrpc
->bio_lock
);
917 bio_list_add(&rrpc
->requeue_bios
, bio
);
918 spin_unlock(&rrpc
->bio_lock
);
919 queue_work(rrpc
->kgc_wq
, &rrpc
->ws_requeue
);
923 mempool_free(rqd
, rrpc
->rq_pool
);
924 return BLK_QC_T_NONE
;
927 static void rrpc_requeue(struct work_struct
*work
)
929 struct rrpc
*rrpc
= container_of(work
, struct rrpc
, ws_requeue
);
930 struct bio_list bios
;
933 bio_list_init(&bios
);
935 spin_lock(&rrpc
->bio_lock
);
936 bio_list_merge(&bios
, &rrpc
->requeue_bios
);
937 bio_list_init(&rrpc
->requeue_bios
);
938 spin_unlock(&rrpc
->bio_lock
);
940 while ((bio
= bio_list_pop(&bios
)))
941 rrpc_make_rq(rrpc
->disk
->queue
, bio
);
944 static void rrpc_gc_free(struct rrpc
*rrpc
)
947 destroy_workqueue(rrpc
->krqd_wq
);
950 destroy_workqueue(rrpc
->kgc_wq
);
953 static int rrpc_gc_init(struct rrpc
*rrpc
)
955 rrpc
->krqd_wq
= alloc_workqueue("rrpc-lun", WQ_MEM_RECLAIM
|WQ_UNBOUND
,
960 rrpc
->kgc_wq
= alloc_workqueue("rrpc-bg", WQ_MEM_RECLAIM
, 1);
964 setup_timer(&rrpc
->gc_timer
, rrpc_gc_timer
, (unsigned long)rrpc
);
969 static void rrpc_map_free(struct rrpc
*rrpc
)
971 vfree(rrpc
->rev_trans_map
);
972 vfree(rrpc
->trans_map
);
975 static int rrpc_l2p_update(u64 slba
, u32 nlb
, __le64
*entries
, void *private)
977 struct rrpc
*rrpc
= (struct rrpc
*)private;
978 struct nvm_dev
*dev
= rrpc
->dev
;
979 struct rrpc_addr
*addr
= rrpc
->trans_map
+ slba
;
980 struct rrpc_rev_addr
*raddr
= rrpc
->rev_trans_map
;
981 u64 elba
= slba
+ nlb
;
984 if (unlikely(elba
> dev
->total_secs
)) {
985 pr_err("nvm: L2P data from device is out of bounds!\n");
989 for (i
= 0; i
< nlb
; i
++) {
990 u64 pba
= le64_to_cpu(entries
[i
]);
992 /* LNVM treats address-spaces as silos, LBA and PBA are
993 * equally large and zero-indexed.
995 if (unlikely(pba
>= dev
->total_secs
&& pba
!= U64_MAX
)) {
996 pr_err("nvm: L2P data entry is out of bounds!\n");
1000 /* Address zero is a special one. The first page on a disk is
1001 * protected. As it often holds internal device boot
1007 div_u64_rem(pba
, rrpc
->nr_sects
, &mod
);
1010 raddr
[mod
].addr
= slba
+ i
;
1016 static int rrpc_map_init(struct rrpc
*rrpc
)
1018 struct nvm_dev
*dev
= rrpc
->dev
;
1022 rrpc
->trans_map
= vzalloc(sizeof(struct rrpc_addr
) * rrpc
->nr_sects
);
1023 if (!rrpc
->trans_map
)
1026 rrpc
->rev_trans_map
= vmalloc(sizeof(struct rrpc_rev_addr
)
1028 if (!rrpc
->rev_trans_map
)
1031 for (i
= 0; i
< rrpc
->nr_sects
; i
++) {
1032 struct rrpc_addr
*p
= &rrpc
->trans_map
[i
];
1033 struct rrpc_rev_addr
*r
= &rrpc
->rev_trans_map
[i
];
1035 p
->addr
= ADDR_EMPTY
;
1036 r
->addr
= ADDR_EMPTY
;
1039 if (!dev
->ops
->get_l2p_tbl
)
1042 /* Bring up the mapping table from device */
1043 ret
= dev
->ops
->get_l2p_tbl(dev
, rrpc
->soffset
, rrpc
->nr_sects
,
1044 rrpc_l2p_update
, rrpc
);
1046 pr_err("nvm: rrpc: could not read L2P table.\n");
1053 /* Minimum pages needed within a lun */
1054 #define PAGE_POOL_SIZE 16
1055 #define ADDR_POOL_SIZE 64
1057 static int rrpc_core_init(struct rrpc
*rrpc
)
1059 down_write(&rrpc_lock
);
1060 if (!rrpc_gcb_cache
) {
1061 rrpc_gcb_cache
= kmem_cache_create("rrpc_gcb",
1062 sizeof(struct rrpc_block_gc
), 0, 0, NULL
);
1063 if (!rrpc_gcb_cache
) {
1064 up_write(&rrpc_lock
);
1068 rrpc_rq_cache
= kmem_cache_create("rrpc_rq",
1069 sizeof(struct nvm_rq
) + sizeof(struct rrpc_rq
),
1071 if (!rrpc_rq_cache
) {
1072 kmem_cache_destroy(rrpc_gcb_cache
);
1073 up_write(&rrpc_lock
);
1077 up_write(&rrpc_lock
);
1079 rrpc
->page_pool
= mempool_create_page_pool(PAGE_POOL_SIZE
, 0);
1080 if (!rrpc
->page_pool
)
1083 rrpc
->gcb_pool
= mempool_create_slab_pool(rrpc
->dev
->nr_luns
,
1085 if (!rrpc
->gcb_pool
)
1088 rrpc
->rq_pool
= mempool_create_slab_pool(64, rrpc_rq_cache
);
1092 spin_lock_init(&rrpc
->inflights
.lock
);
1093 INIT_LIST_HEAD(&rrpc
->inflights
.reqs
);
1098 static void rrpc_core_free(struct rrpc
*rrpc
)
1100 mempool_destroy(rrpc
->page_pool
);
1101 mempool_destroy(rrpc
->gcb_pool
);
1102 mempool_destroy(rrpc
->rq_pool
);
1105 static void rrpc_luns_free(struct rrpc
*rrpc
)
1107 struct nvm_dev
*dev
= rrpc
->dev
;
1108 struct nvm_lun
*lun
;
1109 struct rrpc_lun
*rlun
;
1115 for (i
= 0; i
< rrpc
->nr_luns
; i
++) {
1116 rlun
= &rrpc
->luns
[i
];
1120 dev
->mt
->release_lun(dev
, lun
->id
);
1121 vfree(rlun
->blocks
);
1127 static int rrpc_luns_init(struct rrpc
*rrpc
, int lun_begin
, int lun_end
)
1129 struct nvm_dev
*dev
= rrpc
->dev
;
1130 struct rrpc_lun
*rlun
;
1131 int i
, j
, ret
= -EINVAL
;
1133 if (dev
->sec_per_blk
> MAX_INVALID_PAGES_STORAGE
* BITS_PER_LONG
) {
1134 pr_err("rrpc: number of pages per block too high.");
1138 spin_lock_init(&rrpc
->rev_lock
);
1140 rrpc
->luns
= kcalloc(rrpc
->nr_luns
, sizeof(struct rrpc_lun
),
1146 for (i
= 0; i
< rrpc
->nr_luns
; i
++) {
1147 int lunid
= lun_begin
+ i
;
1148 struct nvm_lun
*lun
;
1150 if (dev
->mt
->reserve_lun(dev
, lunid
)) {
1151 pr_err("rrpc: lun %u is already allocated\n", lunid
);
1155 lun
= dev
->mt
->get_lun(dev
, lunid
);
1159 rlun
= &rrpc
->luns
[i
];
1161 rlun
->blocks
= vzalloc(sizeof(struct rrpc_block
) *
1162 rrpc
->dev
->blks_per_lun
);
1163 if (!rlun
->blocks
) {
1168 for (j
= 0; j
< rrpc
->dev
->blks_per_lun
; j
++) {
1169 struct rrpc_block
*rblk
= &rlun
->blocks
[j
];
1170 struct nvm_block
*blk
= &lun
->blocks
[j
];
1174 INIT_LIST_HEAD(&rblk
->prio
);
1175 spin_lock_init(&rblk
->lock
);
1179 INIT_LIST_HEAD(&rlun
->prio_list
);
1181 INIT_WORK(&rlun
->ws_gc
, rrpc_lun_gc
);
1182 spin_lock_init(&rlun
->lock
);
1190 /* returns 0 on success and stores the beginning address in *begin */
1191 static int rrpc_area_init(struct rrpc
*rrpc
, sector_t
*begin
)
1193 struct nvm_dev
*dev
= rrpc
->dev
;
1194 struct nvmm_type
*mt
= dev
->mt
;
1195 sector_t size
= rrpc
->nr_sects
* dev
->sec_size
;
1200 ret
= mt
->get_area(dev
, begin
, size
);
1202 *begin
>>= (ilog2(dev
->sec_size
) - 9);
1207 static void rrpc_area_free(struct rrpc
*rrpc
)
1209 struct nvm_dev
*dev
= rrpc
->dev
;
1210 struct nvmm_type
*mt
= dev
->mt
;
1211 sector_t begin
= rrpc
->soffset
<< (ilog2(dev
->sec_size
) - 9);
1213 mt
->put_area(dev
, begin
);
1216 static void rrpc_free(struct rrpc
*rrpc
)
1219 rrpc_map_free(rrpc
);
1220 rrpc_core_free(rrpc
);
1221 rrpc_luns_free(rrpc
);
1222 rrpc_area_free(rrpc
);
1227 static void rrpc_exit(void *private)
1229 struct rrpc
*rrpc
= private;
1231 del_timer(&rrpc
->gc_timer
);
1233 flush_workqueue(rrpc
->krqd_wq
);
1234 flush_workqueue(rrpc
->kgc_wq
);
1239 static sector_t
rrpc_capacity(void *private)
1241 struct rrpc
*rrpc
= private;
1242 struct nvm_dev
*dev
= rrpc
->dev
;
1243 sector_t reserved
, provisioned
;
1245 /* cur, gc, and two emergency blocks for each lun */
1246 reserved
= rrpc
->nr_luns
* dev
->sec_per_blk
* 4;
1247 provisioned
= rrpc
->nr_sects
- reserved
;
1249 if (reserved
> rrpc
->nr_sects
) {
1250 pr_err("rrpc: not enough space available to expose storage.\n");
1254 sector_div(provisioned
, 10);
1255 return provisioned
* 9 * NR_PHY_IN_LOG
;
1259 * Looks up the logical address from reverse trans map and check if its valid by
1260 * comparing the logical to physical address with the physical address.
1261 * Returns 0 on free, otherwise 1 if in use
1263 static void rrpc_block_map_update(struct rrpc
*rrpc
, struct rrpc_block
*rblk
)
1265 struct nvm_dev
*dev
= rrpc
->dev
;
1267 struct rrpc_addr
*laddr
;
1268 u64 bpaddr
, paddr
, pladdr
;
1270 bpaddr
= block_to_rel_addr(rrpc
, rblk
);
1271 for (offset
= 0; offset
< dev
->sec_per_blk
; offset
++) {
1272 paddr
= bpaddr
+ offset
;
1274 pladdr
= rrpc
->rev_trans_map
[paddr
].addr
;
1275 if (pladdr
== ADDR_EMPTY
)
1278 laddr
= &rrpc
->trans_map
[pladdr
];
1280 if (paddr
== laddr
->addr
) {
1283 set_bit(offset
, rblk
->invalid_pages
);
1284 rblk
->nr_invalid_pages
++;
1289 static int rrpc_blocks_init(struct rrpc
*rrpc
)
1291 struct rrpc_lun
*rlun
;
1292 struct rrpc_block
*rblk
;
1293 int lun_iter
, blk_iter
;
1295 for (lun_iter
= 0; lun_iter
< rrpc
->nr_luns
; lun_iter
++) {
1296 rlun
= &rrpc
->luns
[lun_iter
];
1298 for (blk_iter
= 0; blk_iter
< rrpc
->dev
->blks_per_lun
;
1300 rblk
= &rlun
->blocks
[blk_iter
];
1301 rrpc_block_map_update(rrpc
, rblk
);
1308 static int rrpc_luns_configure(struct rrpc
*rrpc
)
1310 struct rrpc_lun
*rlun
;
1311 struct rrpc_block
*rblk
;
1314 for (i
= 0; i
< rrpc
->nr_luns
; i
++) {
1315 rlun
= &rrpc
->luns
[i
];
1317 rblk
= rrpc_get_blk(rrpc
, rlun
, 0);
1321 rrpc_set_lun_cur(rlun
, rblk
);
1323 /* Emergency gc block */
1324 rblk
= rrpc_get_blk(rrpc
, rlun
, 1);
1327 rlun
->gc_cur
= rblk
;
1332 rrpc_put_blks(rrpc
);
1336 static struct nvm_tgt_type tt_rrpc
;
1338 static void *rrpc_init(struct nvm_dev
*dev
, struct gendisk
*tdisk
,
1339 int lun_begin
, int lun_end
)
1341 struct request_queue
*bqueue
= dev
->q
;
1342 struct request_queue
*tqueue
= tdisk
->queue
;
1347 if (!(dev
->identity
.dom
& NVM_RSP_L2P
)) {
1348 pr_err("nvm: rrpc: device does not support l2p (%x)\n",
1350 return ERR_PTR(-EINVAL
);
1353 rrpc
= kzalloc(sizeof(struct rrpc
), GFP_KERNEL
);
1355 return ERR_PTR(-ENOMEM
);
1357 rrpc
->instance
.tt
= &tt_rrpc
;
1361 bio_list_init(&rrpc
->requeue_bios
);
1362 spin_lock_init(&rrpc
->bio_lock
);
1363 INIT_WORK(&rrpc
->ws_requeue
, rrpc_requeue
);
1365 rrpc
->nr_luns
= lun_end
- lun_begin
+ 1;
1366 rrpc
->total_blocks
= (unsigned long)dev
->blks_per_lun
* rrpc
->nr_luns
;
1367 rrpc
->nr_sects
= (unsigned long long)dev
->sec_per_lun
* rrpc
->nr_luns
;
1369 /* simple round-robin strategy */
1370 atomic_set(&rrpc
->next_lun
, -1);
1372 ret
= rrpc_area_init(rrpc
, &soffset
);
1374 pr_err("nvm: rrpc: could not initialize area\n");
1375 return ERR_PTR(ret
);
1377 rrpc
->soffset
= soffset
;
1379 ret
= rrpc_luns_init(rrpc
, lun_begin
, lun_end
);
1381 pr_err("nvm: rrpc: could not initialize luns\n");
1385 rrpc
->poffset
= dev
->sec_per_lun
* lun_begin
;
1386 rrpc
->lun_offset
= lun_begin
;
1388 ret
= rrpc_core_init(rrpc
);
1390 pr_err("nvm: rrpc: could not initialize core\n");
1394 ret
= rrpc_map_init(rrpc
);
1396 pr_err("nvm: rrpc: could not initialize maps\n");
1400 ret
= rrpc_blocks_init(rrpc
);
1402 pr_err("nvm: rrpc: could not initialize state for blocks\n");
1406 ret
= rrpc_luns_configure(rrpc
);
1408 pr_err("nvm: rrpc: not enough blocks available in LUNs.\n");
1412 ret
= rrpc_gc_init(rrpc
);
1414 pr_err("nvm: rrpc: could not initialize gc\n");
1418 /* inherit the size from the underlying device */
1419 blk_queue_logical_block_size(tqueue
, queue_physical_block_size(bqueue
));
1420 blk_queue_max_hw_sectors(tqueue
, queue_max_hw_sectors(bqueue
));
1422 pr_info("nvm: rrpc initialized with %u luns and %llu pages.\n",
1423 rrpc
->nr_luns
, (unsigned long long)rrpc
->nr_sects
);
1425 mod_timer(&rrpc
->gc_timer
, jiffies
+ msecs_to_jiffies(10));
1430 return ERR_PTR(ret
);
1433 /* round robin, page-based FTL, and cost-based GC */
1434 static struct nvm_tgt_type tt_rrpc
= {
1436 .version
= {1, 0, 0},
1438 .make_rq
= rrpc_make_rq
,
1439 .capacity
= rrpc_capacity
,
1440 .end_io
= rrpc_end_io
,
1446 static int __init
rrpc_module_init(void)
1448 return nvm_register_tgt_type(&tt_rrpc
);
1451 static void rrpc_module_exit(void)
1453 nvm_unregister_tgt_type(&tt_rrpc
);
1456 module_init(rrpc_module_init
);
1457 module_exit(rrpc_module_exit
);
1458 MODULE_LICENSE("GPL v2");
1459 MODULE_DESCRIPTION("Block-Device Target for Open-Channel SSDs");