Commit 800c2439 authored by Shin'ichiro Kawasaki's avatar Shin'ichiro Kawasaki Committed by Jens Axboe
Browse files

null_blk: introduce badblocks_once parameter 



When IO errors happen on real storage devices, the IOs repeated to the
same target range can success by virtue of recovery features by devices,
such as reserved block assignment. To simulate such IO errors and
recoveries, introduce the new parameter badblocks_once parameter. When
this parameter is set to 1, the specified badblocks are cleared after
the first IO error, so that the next IO to the blocks succeed.

Reviewed-by: default avatarDamien Le Moal <dlemoal@kernel.org>
Reviewed-by: default avatarChaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: default avatarJohannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: default avatarShin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Link: https://lore.kernel.org/r/20250226100613.1622564-3-shinichiro.kawasaki@wdc.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 2cadb8ef

drivers/block/null_blk/main.c

+8 −3
Original line number Diff line number Diff line
@@ -473,6 +473,7 @@ NULLB_DEVICE_ATTR(shared_tags, bool, NULL); 
NULLB_DEVICE_ATTR(shared_tag_bitmap, bool, NULL);

NULLB_DEVICE_ATTR(fua, bool, NULL);

NULLB_DEVICE_ATTR(rotational, bool, NULL);

NULLB_DEVICE_ATTR(badblocks_once, bool, NULL);



static ssize_t nullb_device_power_show(struct config_item *item, char *page)

{
@@ -593,6 +594,7 @@ CONFIGFS_ATTR_WO(nullb_device_, zone_offline); 


static struct configfs_attribute *nullb_device_attrs[] = {

	&nullb_device_attr_badblocks,

	&nullb_device_attr_badblocks_once,

	&nullb_device_attr_blocking,

	&nullb_device_attr_blocksize,

	&nullb_device_attr_cache_size,
@@ -1315,10 +1317,13 @@ static inline blk_status_t null_handle_badblocks(struct nullb_cmd *cmd, 
	sector_t first_bad;

	int bad_sectors;



	if (badblocks_check(bb, sector, nr_sectors, &first_bad, &bad_sectors))

		return BLK_STS_IOERR;



	if (!badblocks_check(bb, sector, nr_sectors, &first_bad, &bad_sectors))

		return BLK_STS_OK;



	if (cmd->nq->dev->badblocks_once)

		badblocks_clear(bb, first_bad, bad_sectors);



	return BLK_STS_IOERR;

}



static inline blk_status_t null_handle_memory_backed(struct nullb_cmd *cmd,

drivers/block/null_blk/null_blk.h

+1 −0
Original line number Diff line number Diff line
@@ -63,6 +63,7 @@ struct nullb_device { 
	unsigned long flags; /* device flags */

	unsigned int curr_cache;

	struct badblocks badblocks;

	bool badblocks_once;



	unsigned int nr_zones;

	unsigned int nr_zones_imp_open;