> On 14 Mar 2019, at 17.04, Igor Konopko <igor.j.konopko@intel.com> wrote:
> 
> Currently when there is an IO error (or similar) on GC read path, pblk
> still moves this line to free state, what leads to data mismatch issue.
> 
> This patch adds a handling for such an error - after that changes this
> line will be returned to closed state so it can be still in use
> for reading - at least we will be able to return error status to user
> when user tries to read such a data.
> 
> Signed-off-by: Igor Konopko <igor.j.konopko@intel.com>
> ---
> drivers/lightnvm/pblk-core.c | 8 ++++++++
> drivers/lightnvm/pblk-gc.c   | 5 ++---
> drivers/lightnvm/pblk-read.c | 1 -
> drivers/lightnvm/pblk.h      | 2 ++
> 4 files changed, 12 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/lightnvm/pblk-core.c b/drivers/lightnvm/pblk-core.c
> index 4d5cd99..6817f8f 100644
> --- a/drivers/lightnvm/pblk-core.c
> +++ b/drivers/lightnvm/pblk-core.c
> @@ -1786,6 +1786,14 @@ static void __pblk_line_put(struct pblk *pblk, struct pblk_line *line)
> 
> 	spin_lock(&line->lock);
> 	WARN_ON(line->state != PBLK_LINESTATE_GC);
> +	if (line->w_err_gc->has_gc_err) {
> +		spin_unlock(&line->lock);
> +		pblk_err(pblk, "line %d had errors during GC\n", line->id);
> +		pblk_put_line_back(pblk, line);
> +		line->w_err_gc->has_gc_err = 0;
> +		return;
> +	}
> +
> 	line->state = PBLK_LINESTATE_FREE;
> 	trace_pblk_line_state(pblk_disk_name(pblk), line->id,
> 					line->state);
> diff --git a/drivers/lightnvm/pblk-gc.c b/drivers/lightnvm/pblk-gc.c
> index e23b192..63ee205 100644
> --- a/drivers/lightnvm/pblk-gc.c
> +++ b/drivers/lightnvm/pblk-gc.c
> @@ -59,7 +59,7 @@ static void pblk_gc_writer_kick(struct pblk_gc *gc)
> 	wake_up_process(gc->gc_writer_ts);
> }
> 
> -static void pblk_put_line_back(struct pblk *pblk, struct pblk_line *line)
> +void pblk_put_line_back(struct pblk *pblk, struct pblk_line *line)
> {
> 	struct pblk_line_mgmt *l_mg = &pblk->l_mg;
> 	struct list_head *move_list;
> @@ -98,8 +98,7 @@ static void pblk_gc_line_ws(struct work_struct *work)
> 	/* Read from GC victim block */
> 	ret = pblk_submit_read_gc(pblk, gc_rq);
> 	if (ret) {
> -		pblk_err(pblk, "failed GC read in line:%d (err:%d)\n",
> -								line->id, ret);
> +		line->w_err_gc->has_gc_err = 1;
> 		goto out;
> 	}
> 
> diff --git a/drivers/lightnvm/pblk-read.c b/drivers/lightnvm/pblk-read.c
> index 54422a2..6a77c24 100644
> --- a/drivers/lightnvm/pblk-read.c
> +++ b/drivers/lightnvm/pblk-read.c
> @@ -475,7 +475,6 @@ int pblk_submit_read_gc(struct pblk *pblk, struct pblk_gc_rq *gc_rq)
> 
> 	if (pblk_submit_io_sync(pblk, &rqd)) {
> 		ret = -EIO;
> -		pblk_err(pblk, "GC read request failed\n");
> 		goto err_free_bio;
> 	}
> 
> diff --git a/drivers/lightnvm/pblk.h b/drivers/lightnvm/pblk.h
> index 5d1040a..52002f5 100644
> --- a/drivers/lightnvm/pblk.h
> +++ b/drivers/lightnvm/pblk.h
> @@ -427,6 +427,7 @@ struct pblk_smeta {
> 
> struct pblk_w_err_gc {
> 	int has_write_err;
> +	int has_gc_err;
> 	__le64 *lba_list;
> };
> 
> @@ -909,6 +910,7 @@ void pblk_gc_free_full_lines(struct pblk *pblk);
> void pblk_gc_sysfs_state_show(struct pblk *pblk, int *gc_enabled,
> 			      int *gc_active);
> int pblk_gc_sysfs_force(struct pblk *pblk, int force);
> +void pblk_put_line_back(struct pblk *pblk, struct pblk_line *line);
> 
> /*
>  * pblk rate limiter
> --
> 2.9.5

Looks good to me.


Reviewed-by: Javier González <javier@javigon.com>