Re: [PATCH 17/19] lightnvm: pblk: implement get log report chunk

["Matias Bjørling" <mb@lightnvm.io>]

On 02/26/2018 02:17 PM, Javier González wrote:
> From: Javier González <javier@javigon.com>
> 
> In preparation of pblk supporting 2.0, implement the get log report
> chunk in pblk.
> 
> This patch only replicates de bad block functionality as the rest of the
> metadata requires new pblk functionality (e.g., wear-index to implement
> wear-leveling). 


"This functionality will come in future patches."

I think the  above belongs in the cover letter, not in the patch 
description.

> 
> Signed-off-by: Javier González <javier@cnexlabs.com>
> ---
>   drivers/lightnvm/pblk-core.c  | 121 +++++++++++++++++++----
>   drivers/lightnvm/pblk-init.c  | 218 ++++++++++++++++++++++++++++++------------
>   drivers/lightnvm/pblk-sysfs.c |  67 +++++++++++++
>   drivers/lightnvm/pblk.h       |  20 ++++
>   4 files changed, 346 insertions(+), 80 deletions(-)
> 
> diff --git a/drivers/lightnvm/pblk-core.c b/drivers/lightnvm/pblk-core.c
> index 1d7c6313f3d9..ce6a7cfdba66 100644
> --- a/drivers/lightnvm/pblk-core.c
> +++ b/drivers/lightnvm/pblk-core.c
> @@ -44,11 +44,12 @@ static void pblk_line_mark_bb(struct work_struct *work)
>   }
>   
>   static void pblk_mark_bb(struct pblk *pblk, struct pblk_line *line,
> -			 struct ppa_addr *ppa)
> +			 struct ppa_addr ppa_addr)
>   {
>   	struct nvm_tgt_dev *dev = pblk->dev;
>   	struct nvm_geo *geo = &dev->geo;
> -	int pos = pblk_ppa_to_pos(geo, *ppa);
> +	struct ppa_addr *ppa;
> +	int pos = pblk_ppa_to_pos(geo, ppa_addr);
>   
>   	pr_debug("pblk: erase failed: line:%d, pos:%d\n", line->id, pos);
>   	atomic_long_inc(&pblk->erase_failed);
> @@ -58,6 +59,15 @@ static void pblk_mark_bb(struct pblk *pblk, struct pblk_line *line,
>   		pr_err("pblk: attempted to erase bb: line:%d, pos:%d\n",
>   							line->id, pos);
>   
> +	/* Not necessary to mark bad blocks on 2.0 spec. */
> +	if (geo->c.version == NVM_OCSSD_SPEC_20)
> +		return;
> +
> +	ppa = kmalloc(sizeof(struct ppa_addr), GFP_ATOMIC);
> +	if (!ppa)
> +		return;
> +
> +	*ppa = ppa_addr;
>   	pblk_gen_run_ws(pblk, NULL, ppa, pblk_line_mark_bb,
>   						GFP_ATOMIC, pblk->bb_wq);
>   }
> @@ -69,16 +79,8 @@ static void __pblk_end_io_erase(struct pblk *pblk, struct nvm_rq *rqd)
>   	line = &pblk->lines[pblk_ppa_to_line(rqd->ppa_addr)];
>   	atomic_dec(&line->left_seblks);
>   
> -	if (rqd->error) {
> -		struct ppa_addr *ppa;
> -
> -		ppa = kmalloc(sizeof(struct ppa_addr), GFP_ATOMIC);
> -		if (!ppa)
> -			return;
> -
> -		*ppa = rqd->ppa_addr;
> -		pblk_mark_bb(pblk, line, ppa);
> -	}
> +	if (rqd->error)
> +		pblk_mark_bb(pblk, line, rqd->ppa_addr);
>   
>   	atomic_dec(&pblk->inflight_io);
>   }
> @@ -92,6 +94,50 @@ static void pblk_end_io_erase(struct nvm_rq *rqd)
>   	mempool_free(rqd, pblk->e_rq_pool);
>   }
>   
> +/*
> + * Get information for all chunks from the device.
> + *
> + * The caller is responsible for freeing the returned structure
> + */
> +struct nvm_chk_meta *pblk_chunk_get_info(struct pblk *pblk)
> +{
> +	struct nvm_tgt_dev *dev = pblk->dev;
> +	struct nvm_geo *geo = &dev->geo;
> +	struct nvm_chk_meta *meta;
> +	struct ppa_addr ppa;
> +	unsigned long len;
> +	int ret;
> +
> +	ppa.ppa = 0;
> +
> +	len = geo->all_chunks * sizeof(*meta);
> +	meta = kzalloc(len, GFP_KERNEL);
> +	if (!meta)
> +		return ERR_PTR(-ENOMEM);
> +
> +	ret = nvm_get_chunk_meta(dev, meta, ppa, geo->all_chunks);
> +	if (ret) {
> +		pr_err("pblk: could not get chunk metadata (%d)\n", ret);
> +		kfree(meta);
> +		return ERR_PTR(-EIO);
> +	}
> +
> +	return meta;
> +}
> +
> +struct nvm_chk_meta *pblk_chunk_get_off(struct pblk *pblk,
> +					      struct nvm_chk_meta *meta,
> +					      struct ppa_addr ppa)
> +{
> +	struct nvm_tgt_dev *dev = pblk->dev;
> +	struct nvm_geo *geo = &dev->geo;
> +	int ch_off = ppa.m.grp * geo->c.num_chk * geo->num_lun;
> +	int lun_off = ppa.m.pu * geo->c.num_chk;
> +	int chk_off = ppa.m.chk;
> +
> +	return meta + ch_off + lun_off + chk_off;
> +}
> +
>   void __pblk_map_invalidate(struct pblk *pblk, struct pblk_line *line,
>   			   u64 paddr)
>   {
> @@ -1094,10 +1140,38 @@ static int pblk_line_init_bb(struct pblk *pblk, struct pblk_line *line,
>   	return 1;
>   }
>   
> +static int pblk_prepare_new_line(struct pblk *pblk, struct pblk_line *line)
> +{
> +	struct pblk_line_meta *lm = &pblk->lm;
> +	struct nvm_tgt_dev *dev = pblk->dev;
> +	struct nvm_geo *geo = &dev->geo;
> +	int blk_to_erase = atomic_read(&line->blk_in_line);
> +	int i;
> +
> +	for (i = 0; i < lm->blk_per_line; i++) {
> +		int state = line->chks[i].state;
> +		struct pblk_lun *rlun = &pblk->luns[i];
> +
> +		/* Free chunks should not be erased */
> +		if (state & NVM_CHK_ST_FREE) {
> +			set_bit(pblk_ppa_to_pos(geo, rlun->chunk_bppa),
> +					line->erase_bitmap);
> +			blk_to_erase--;
> +			line->chks[i].state = NVM_CHK_ST_HOST_USE;


Can you help me understand why you want to use The NVM_CHK_ST_HOST_USE? 
Why would I care if the chunk state is HOST_USE? A target instance 
should not be able to see states from other chunks it doesn't own. and 
in that case, why have a separate state?


> +		}
> +
> +		WARN_ONCE(state & NVM_CHK_ST_OPEN,
> +				"pblk: open chunk in new line: %d\n",
> +				line->id);
> +	}
> +
> +	return blk_to_erase;
> +}
> +
>   static int pblk_line_prepare(struct pblk *pblk, struct pblk_line *line)
>   {
>   	struct pblk_line_meta *lm = &pblk->lm;
> -	int blk_in_line = atomic_read(&line->blk_in_line);
> +	int blk_to_erase;
>   
>   	line->map_bitmap = kzalloc(lm->sec_bitmap_len, GFP_ATOMIC);
>   	if (!line->map_bitmap)
> @@ -1110,7 +1184,21 @@ static int pblk_line_prepare(struct pblk *pblk, struct pblk_line *line)
>   		return -ENOMEM;
>   	}
>   
> +	/* Bad blocks do not need to be erased */
> +	bitmap_copy(line->erase_bitmap, line->blk_bitmap, lm->blk_per_line);
> +
>   	spin_lock(&line->lock);
> +
> +	/* If we have not written to this line, we need to mark up free chunks
> +	 * as already erased
> +	 */
> +	if (line->state == PBLK_LINESTATE_NEW) {
> +		blk_to_erase = pblk_prepare_new_line(pblk, line);
> +		line->state = PBLK_LINESTATE_FREE;
> +	} else {
> +		blk_to_erase = atomic_read(&line->blk_in_line);
> +	}
> +
>   	if (line->state != PBLK_LINESTATE_FREE) {
>   		kfree(line->map_bitmap);
>   		kfree(line->invalid_bitmap);
> @@ -1122,15 +1210,12 @@ static int pblk_line_prepare(struct pblk *pblk, struct pblk_line *line)
>   
>   	line->state = PBLK_LINESTATE_OPEN;
>   
> -	atomic_set(&line->left_eblks, blk_in_line);
> -	atomic_set(&line->left_seblks, blk_in_line);
> +	atomic_set(&line->left_eblks, blk_to_erase);
> +	atomic_set(&line->left_seblks, blk_to_erase);
>   
>   	line->meta_distance = lm->meta_distance;
>   	spin_unlock(&line->lock);
>   
> -	/* Bad blocks do not need to be erased */
> -	bitmap_copy(line->erase_bitmap, line->blk_bitmap, lm->blk_per_line);
> -
>   	kref_init(&line->ref);
>   
>   	return 0;
> diff --git a/drivers/lightnvm/pblk-init.c b/drivers/lightnvm/pblk-init.c
> index ec39800eea42..cf4f49d48aed 100644
> --- a/drivers/lightnvm/pblk-init.c
> +++ b/drivers/lightnvm/pblk-init.c
> @@ -401,6 +401,7 @@ static void pblk_line_meta_free(struct pblk_line *line)
>   {
>   	kfree(line->blk_bitmap);
>   	kfree(line->erase_bitmap);
> +	kfree(line->chks);
>   }
>   
>   static void pblk_lines_free(struct pblk *pblk)
> @@ -440,54 +441,44 @@ static int pblk_bb_get_tbl(struct nvm_tgt_dev *dev, struct pblk_lun *rlun,
>   	return 0;
>   }
>   
> -static void *pblk_bb_get_log(struct pblk *pblk)
> +static void *pblk_bb_get_meta(struct pblk *pblk)
>   {
>   	struct nvm_tgt_dev *dev = pblk->dev;
>   	struct nvm_geo *geo = &dev->geo;
> -	u8 *log;
> +	u8 *meta;
>   	int i, nr_blks, blk_per_lun;
>   	int ret;
>   
>   	blk_per_lun = geo->c.num_chk * geo->c.pln_mode;
>   	nr_blks = blk_per_lun * geo->all_luns;
>   
> -	log = kmalloc(nr_blks, GFP_KERNEL);
> -	if (!log)
> +	meta = kmalloc(nr_blks, GFP_KERNEL);
> +	if (!meta)
>   		return ERR_PTR(-ENOMEM);
>   
>   	for (i = 0; i < geo->all_luns; i++) {
>   		struct pblk_lun *rlun = &pblk->luns[i];
> -		u8 *log_pos = log + i * blk_per_lun;
> +		u8 *meta_pos = meta + i * blk_per_lun;
>   
> -		ret = pblk_bb_get_tbl(dev, rlun, log_pos, blk_per_lun);
> +		ret = pblk_bb_get_tbl(dev, rlun, meta_pos, blk_per_lun);
>   		if (ret) {
> -			kfree(log);
> +			kfree(meta);
>   			return ERR_PTR(-EIO);
>   		}
>   	}
>   
> -	return log;
> +	return meta;
>   }
>   
> -static int pblk_bb_line(struct pblk *pblk, struct pblk_line *line,
> -			u8 *bb_log, int blk_per_line)
> +static void *pblk_chunk_get_meta(struct pblk *pblk)
>   {
>   	struct nvm_tgt_dev *dev = pblk->dev;
>   	struct nvm_geo *geo = &dev->geo;
> -	int i, bb_cnt = 0;
>   
> -	for (i = 0; i < blk_per_line; i++) {
> -		struct pblk_lun *rlun = &pblk->luns[i];
> -		u8 *lun_bb_log = bb_log + i * blk_per_line;
> -
> -		if (lun_bb_log[line->id] == NVM_BLK_T_FREE)
> -			continue;
> -
> -		set_bit(pblk_ppa_to_pos(geo, rlun->bppa), line->blk_bitmap);
> -		bb_cnt++;
> -	}
> -
> -	return bb_cnt;
> +	if (geo->c.version == NVM_OCSSD_SPEC_12)
> +		return pblk_bb_get_meta(pblk);
> +	else
> +		return pblk_chunk_get_info(pblk);

This 1.2 or 2.0 would be nice to have inside the lightnvm core. A target 
should not care weather it is a 1.2 or 2.0 device.

>   }
>   
>   static int pblk_luns_init(struct pblk *pblk, struct ppa_addr *luns)
> @@ -516,6 +507,7 @@ static int pblk_luns_init(struct pblk *pblk, struct ppa_addr *luns)
>   
>   		rlun = &pblk->luns[i];
>   		rlun->bppa = luns[lunid];
> +		rlun->chunk_bppa = luns[i];
>   
>   		sema_init(&rlun->wr_sem, 1);
>   	}
> @@ -695,8 +687,125 @@ static int pblk_lines_alloc_metadata(struct pblk *pblk)
>   	return -ENOMEM;
>   }
>   
> -static int pblk_setup_line_meta(struct pblk *pblk, struct pblk_line *line,
> -				void *chunk_log, long *nr_bad_blks)
> +static int pblk_setup_line_meta_12(struct pblk *pblk, struct pblk_line *line,
> +				   void *chunk_meta)
> +{
> +	struct nvm_tgt_dev *dev = pblk->dev;
> +	struct nvm_geo *geo = &dev->geo;
> +	struct pblk_line_meta *lm = &pblk->lm;
> +	int i, chk_per_lun, nr_bad_chks = 0;
> +
> +	chk_per_lun = geo->c.num_chk * geo->c.pln_mode;
> +
> +	for (i = 0; i < lm->blk_per_line; i++) {
> +		struct pblk_chunk *chunk = &line->chks[i];
> +		struct pblk_lun *rlun = &pblk->luns[i];
> +		u8 *lun_bb_meta = chunk_meta + i * chk_per_lun;
> +
> +		/*
> +		 * In 1.2 spec. chunk state is not persisted by the device. Thus
> +		 * some of the values are reset each time pblk is instantiated.
> +		 */
> +		if (lun_bb_meta[line->id] == NVM_BLK_T_FREE)
> +			chunk->state =  NVM_CHK_ST_HOST_USE;
> +		else
> +			chunk->state = NVM_CHK_ST_OFFLINE;
> +
> +		chunk->type = NVM_CHK_TP_W_SEQ;
> +		chunk->wi = 0;
> +		chunk->slba = -1;
> +		chunk->cnlb = geo->c.clba;
> +		chunk->wp = 0;
> +
> +		if (!(chunk->state & NVM_CHK_ST_OFFLINE))
> +			continue;
> +
> +		set_bit(pblk_ppa_to_pos(geo, rlun->bppa), line->blk_bitmap);
> +		nr_bad_chks++;
> +	}
> +
> +	return nr_bad_chks;
> +}
> +
> +static int pblk_setup_line_meta_20(struct pblk *pblk, struct pblk_line *line,
> +				   struct nvm_chk_meta *meta)
> +{
> +	struct nvm_tgt_dev *dev = pblk->dev;
> +	struct nvm_geo *geo = &dev->geo;
> +	struct pblk_line_meta *lm = &pblk->lm;
> +	int i, nr_bad_chks = 0;
> +
> +	for (i = 0; i < lm->blk_per_line; i++) {
> +		struct pblk_chunk *chunk = &line->chks[i];
> +		struct pblk_lun *rlun = &pblk->luns[i];
> +		struct nvm_chk_meta *chunk_meta;
> +		struct ppa_addr ppa;
> +
> +		ppa = rlun->chunk_bppa;
> +		ppa.m.chk = line->id;
> +		chunk_meta = pblk_chunk_get_off(pblk, meta, ppa);
> +
> +		chunk->state = chunk_meta->state;
> +		chunk->type = chunk_meta->type;
> +		chunk->wi = chunk_meta->wi;
> +		chunk->slba = chunk_meta->slba;
> +		chunk->cnlb = chunk_meta->cnlb;
> +		chunk->wp = chunk_meta->wp;
> +
> +		if (!(chunk->state & NVM_CHK_ST_OFFLINE))
> +			continue;
> +
> +		if (chunk->type & NVM_CHK_TP_SZ_SPEC) {
> +			WARN_ONCE(1, "pblk: custom-sized chunks unsupported\n");
> +			continue;
> +		}
> +
> +		set_bit(pblk_ppa_to_pos(geo, rlun->chunk_bppa),
> +							line->blk_bitmap);
> +		nr_bad_chks++;
> +	}
> +
> +	return nr_bad_chks;
> +}
> +
> +static long pblk_setup_line_meta(struct pblk *pblk, struct pblk_line *line,
> +				 void *chunk_meta, int line_id)
> +{
> +	struct nvm_tgt_dev *dev = pblk->dev;
> +	struct nvm_geo *geo = &dev->geo;
> +	struct pblk_line_mgmt *l_mg = &pblk->l_mg;
> +	struct pblk_line_meta *lm = &pblk->lm;
> +	long nr_bad_chks, chk_in_line;
> +
> +	line->pblk = pblk;
> +	line->id = line_id;
> +	line->type = PBLK_LINETYPE_FREE;
> +	line->state = PBLK_LINESTATE_NEW;
> +	line->gc_group = PBLK_LINEGC_NONE;
> +	line->vsc = &l_mg->vsc_list[line_id];
> +	spin_lock_init(&line->lock);
> +
> +	if (geo->c.version == NVM_OCSSD_SPEC_12)
> +		nr_bad_chks = pblk_setup_line_meta_12(pblk, line, chunk_meta);
> +	else
> +		nr_bad_chks = pblk_setup_line_meta_20(pblk, line, chunk_meta);
> +
> +	chk_in_line = lm->blk_per_line - nr_bad_chks;
> +	if (nr_bad_chks < 0 || nr_bad_chks > lm->blk_per_line ||
> +					chk_in_line < lm->min_blk_line) {
> +		line->state = PBLK_LINESTATE_BAD;
> +		list_add_tail(&line->list, &l_mg->bad_list);
> +		return 0;
> +	}
> +
> +	atomic_set(&line->blk_in_line, chk_in_line);
> +	list_add_tail(&line->list, &l_mg->free_list);
> +	l_mg->nr_free_lines++;
> +
> +	return chk_in_line;
> +}
> +
> +static int pblk_alloc_line_meta(struct pblk *pblk, struct pblk_line *line)
>   {
>   	struct pblk_line_meta *lm = &pblk->lm;
>   
> @@ -710,7 +819,13 @@ static int pblk_setup_line_meta(struct pblk *pblk, struct pblk_line *line,
>   		return -ENOMEM;
>   	}
>   
> -	*nr_bad_blks = pblk_bb_line(pblk, line, chunk_log, lm->blk_per_line);
> +	line->chks = kmalloc(lm->blk_per_line * sizeof(struct pblk_chunk),
> +								GFP_KERNEL);
> +	if (!line->chks) {
> +		kfree(line->erase_bitmap);
> +		kfree(line->blk_bitmap);
> +		return -ENOMEM;
> +	}
>   
>   	return 0;
>   }
> @@ -722,9 +837,9 @@ static int pblk_lines_init(struct pblk *pblk)
>   	struct pblk_line_mgmt *l_mg = &pblk->l_mg;
>   	struct pblk_line_meta *lm = &pblk->lm;
>   	struct pblk_line *line;
> -	void *chunk_log;
> +	void *chunk_meta;
>   	unsigned int smeta_len, emeta_len;
> -	long nr_bad_blks = 0, nr_free_blks = 0;
> +	long nr_free_chks = 0;
>   	int bb_distance, max_write_ppas;
>   	int i, ret;
>   
> @@ -743,6 +858,7 @@ static int pblk_lines_init(struct pblk *pblk)
>   	l_mg->log_line = l_mg->data_line = NULL;
>   	l_mg->l_seq_nr = l_mg->d_seq_nr = 0;
>   	l_mg->nr_free_lines = 0;
> +	atomic_set(&l_mg->sysfs_line_state, -1);
>   	bitmap_zero(&l_mg->meta_bitmap, PBLK_DATA_LINES);
>   
>   	lm->sec_per_line = geo->c.clba * geo->all_luns;
> @@ -841,53 +957,31 @@ static int pblk_lines_init(struct pblk *pblk)
>   		goto fail_free_bb_aux;
>   	}
>   
> -	chunk_log = pblk_bb_get_log(pblk);
> -	if (IS_ERR(chunk_log)) {
> -		pr_err("pblk: could not get bad block log (%lu)\n",
> -							PTR_ERR(chunk_log));
> -		ret = PTR_ERR(chunk_log);
> +	chunk_meta = pblk_chunk_get_meta(pblk);
> +	if (IS_ERR(chunk_meta)) {
> +		pr_err("pblk: could not get chunk log (%lu)\n",
> +							PTR_ERR(chunk_meta));
> +		ret = PTR_ERR(chunk_meta);
>   		goto fail_free_lines;
>   	}
>   
>   	for (i = 0; i < l_mg->nr_lines; i++) {
> -		int chk_in_line;
> -
>   		line = &pblk->lines[i];
>   
> -		line->pblk = pblk;
> -		line->id = i;
> -		line->type = PBLK_LINETYPE_FREE;
> -		line->state = PBLK_LINESTATE_FREE;
> -		line->gc_group = PBLK_LINEGC_NONE;
> -		line->vsc = &l_mg->vsc_list[i];
> -		spin_lock_init(&line->lock);
> -
> -		ret = pblk_setup_line_meta(pblk, line, chunk_log, &nr_bad_blks);
> +		ret = pblk_alloc_line_meta(pblk, line);
>   		if (ret)
> -			goto fail_free_chunk_log;
> +			goto fail_free_chunk_meta;
>   
> -		chk_in_line = lm->blk_per_line - nr_bad_blks;
> -		if (nr_bad_blks < 0 || nr_bad_blks > lm->blk_per_line ||
> -					chk_in_line < lm->min_blk_line) {
> -			line->state = PBLK_LINESTATE_BAD;
> -			list_add_tail(&line->list, &l_mg->bad_list);
> -			continue;
> -		}
> -
> -		nr_free_blks += chk_in_line;
> -		atomic_set(&line->blk_in_line, chk_in_line);
> -
> -		l_mg->nr_free_lines++;
> -		list_add_tail(&line->list, &l_mg->free_list);
> +		nr_free_chks += pblk_setup_line_meta(pblk, line, chunk_meta, i);
>   	}
>   
> -	pblk_set_provision(pblk, nr_free_blks);
> +	pblk_set_provision(pblk, nr_free_chks);
>   
> -	kfree(chunk_log);
> +	kfree(chunk_meta);
>   	return 0;
>   
> -fail_free_chunk_log:
> -	kfree(chunk_log);
> +fail_free_chunk_meta:
> +	kfree(chunk_meta);
>   	while (--i >= 0)
>   		pblk_line_meta_free(&pblk->lines[i]);
>   fail_free_lines:
> diff --git a/drivers/lightnvm/pblk-sysfs.c b/drivers/lightnvm/pblk-sysfs.c
> index ccfb3abd2773..1ce5b956c622 100644
> --- a/drivers/lightnvm/pblk-sysfs.c
> +++ b/drivers/lightnvm/pblk-sysfs.c
> @@ -142,6 +142,40 @@ static ssize_t pblk_sysfs_ppaf(struct pblk *pblk, char *page)
>   	return sz;
>   }
>   
> +static ssize_t pblk_sysfs_line_state_show(struct pblk *pblk, char *page)
> +{
> +	struct pblk_line_meta *lm = &pblk->lm;
> +	struct pblk_line_mgmt *l_mg = &pblk->l_mg;
> +	struct pblk_line *line;
> +	int line_id = atomic_read(&l_mg->sysfs_line_state);
> +	ssize_t sz = 0;
> +	int i;
> +
> +	if (line_id < 0 || line_id >= l_mg->nr_lines)
> +		return 0;
> +
> +	sz = snprintf(page, PAGE_SIZE,
> +		"line\tchunk\tstate\ttype\twear-index\tslba\t\tcnlb\twp\n");
> +
> +	line = &pblk->lines[line_id];
> +
> +	for (i = 0; i < lm->blk_per_line; i++) {
> +		struct pblk_chunk *chunk = &line->chks[i];
> +
> +		sz += snprintf(page + sz, PAGE_SIZE - sz,
> +				"%d\t%d\t%d\t%d\t%d\t\t%llu\t\t%llu\t%llu\n",
> +				line->id, i,
> +				chunk->state,
> +				chunk->type,
> +				chunk->wi,
> +				chunk->slba,
> +				chunk->cnlb,
> +				chunk->wp);
> +	}
> +
> +	return sz;
> +}
> +
>   static ssize_t pblk_sysfs_lines(struct pblk *pblk, char *page)
>   {
>   	struct nvm_tgt_dev *dev = pblk->dev;
> @@ -398,6 +432,29 @@ static ssize_t pblk_sysfs_stats_debug(struct pblk *pblk, char *page)
>   }
>   #endif
>   
> +
> +static ssize_t pblk_sysfs_line_state_store(struct pblk *pblk, const char *page,
> +					   size_t len)
> +{
> +	struct pblk_line_mgmt *l_mg = &pblk->l_mg;
> +	size_t c_len;
> +	int line_id;
> +
> +	c_len = strcspn(page, "\n");
> +	if (c_len >= len)
> +		return -EINVAL;
> +
> +	if (kstrtouint(page, 0, &line_id))
> +		return -EINVAL;
> +
> +	if (line_id < 0 || line_id >= l_mg->nr_lines)
> +		return -EINVAL;
> +
> +	atomic_set(&l_mg->sysfs_line_state, line_id);
> +
> +	return len;
> +}
> +
>   static ssize_t pblk_sysfs_gc_force(struct pblk *pblk, const char *page,
>   				   size_t len)
>   {
> @@ -529,6 +586,11 @@ static struct attribute sys_lines_info_attr = {
>   	.mode = 0444,
>   };
>   
> +static struct attribute sys_line_state_attr = {
> +	.name = "line_state",
> +	.mode = 0644,
> +};
> +
>   static struct attribute sys_gc_force = {
>   	.name = "gc_force",
>   	.mode = 0200,
> @@ -572,6 +634,7 @@ static struct attribute *pblk_attrs[] = {
>   	&sys_stats_ppaf_attr,
>   	&sys_lines_attr,
>   	&sys_lines_info_attr,
> +	&sys_line_state_attr,
>   	&sys_write_amp_mileage,
>   	&sys_write_amp_trip,
>   	&sys_padding_dist,
> @@ -602,6 +665,8 @@ static ssize_t pblk_sysfs_show(struct kobject *kobj, struct attribute *attr,
>   		return pblk_sysfs_lines(pblk, buf);
>   	else if (strcmp(attr->name, "lines_info") == 0)
>   		return pblk_sysfs_lines_info(pblk, buf);
> +	else if (strcmp(attr->name, "line_state") == 0)
> +		return pblk_sysfs_line_state_show(pblk, buf);
>   	else if (strcmp(attr->name, "max_sec_per_write") == 0)
>   		return pblk_sysfs_get_sec_per_write(pblk, buf);
>   	else if (strcmp(attr->name, "write_amp_mileage") == 0)
> @@ -628,6 +693,8 @@ static ssize_t pblk_sysfs_store(struct kobject *kobj, struct attribute *attr,
>   		return pblk_sysfs_set_sec_per_write(pblk, buf, len);
>   	else if (strcmp(attr->name, "write_amp_trip") == 0)
>   		return pblk_sysfs_set_write_amp_trip(pblk, buf, len);
> +	else if (strcmp(attr->name, "line_state") == 0)
> +		return pblk_sysfs_line_state_store(pblk, buf, len);
>   	else if (strcmp(attr->name, "padding_dist") == 0)
>   		return pblk_sysfs_set_padding_dist(pblk, buf, len);
>   	return 0;
> diff --git a/drivers/lightnvm/pblk.h b/drivers/lightnvm/pblk.h
> index 6e1fcd1a538a..bc31c67b725f 100644
> --- a/drivers/lightnvm/pblk.h
> +++ b/drivers/lightnvm/pblk.h
> @@ -201,6 +201,8 @@ struct pblk_rb {
>   
>   struct pblk_lun {
>   	struct ppa_addr bppa;
> +	struct ppa_addr chunk_bppa;
> +
>   	struct semaphore wr_sem;
>   };
>   
> @@ -297,6 +299,7 @@ enum {
>   	PBLK_LINETYPE_DATA = 2,
>   
>   	/* Line state */
> +	PBLK_LINESTATE_NEW = 9,
>   	PBLK_LINESTATE_FREE = 10,
>   	PBLK_LINESTATE_OPEN = 11,
>   	PBLK_LINESTATE_CLOSED = 12,
> @@ -412,6 +415,15 @@ struct pblk_smeta {
>   	struct line_smeta *buf;		/* smeta buffer in persistent format */
>   };
>   
> +struct pblk_chunk {
> +	int state;
> +	int type;
> +	int wi;
> +	u64 slba;
> +	u64 cnlb;
> +	u64 wp;
> +};
> +

How come the code replicate the nvm_chk_meta data structure?