[PATCH] Apply blk_partition_remap to REQ_OP_ZONE_RESET

[PATCH] Apply blk_partition_remap to REQ_OP_ZONE_RESET

[Shaun Tancheff]

When a Reset WP is requested from a partition offset the blk_partition_remap
should be applied.

Signed-off-by: Shaun Tancheff <shaun.tancheff@seagate.com>
---
Based on for-4.10/block
---
 block/blk-core.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/block/blk-core.c b/block/blk-core.c
index 473dd69..3f85320 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -1786,8 +1786,9 @@ static blk_qc_t blk_queue_bio(struct request_queue *q, struct bio *bio)
 static inline void blk_partition_remap(struct bio *bio)
 {
 	struct block_device *bdev = bio->bi_bdev;
+	bool remap = bio_sectors(bio) != 0 || bio_op(bio) == REQ_OP_ZONE_RESET;
 
-	if (bio_sectors(bio) && bdev != bdev->bd_contains) {
+	if (remap && bdev != bdev->bd_contains) {
 		struct hd_struct *p = bdev->bd_part;
 
 		bio->bi_iter.bi_sector += p->start_sect;
-- 
2.10.2

Re: [PATCH] Apply blk_partition_remap to REQ_OP_ZONE_RESET

[Jens Axboe]

On 11/21/2016 12:00 PM, Shaun Tancheff wrote:
> When a Reset WP is requested from a partition offset the blk_partition_remap
> should be applied.

You need to provide a better explanation in your commit message, and
also put a comment in the code. A good commit message explans WHY
there's a need for the patch.

-- 
Jens Axboe

[PATCH v2] Apply blk_partition_remap to REQ_OP_ZONE_RESET

[Shaun Tancheff]

If a ZBC device is partitioned and operations are performed on the partition
the zone information is rebased to the partition, however the zone reset
is not mapped from the partition to device as are other operations.

This causes the API (report zones / reset zone) to be unbalanced in this
regard. Checking for the zone reset op code explicitly will balance the
API.

Signed-off-by: Shaun Tancheff <shaun.tancheff@seagate.com>
---
v2: 
 - Moved conditional check
 - Added comments and update commit message

Based on for-4.10/block
---
 block/blk-core.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/block/blk-core.c b/block/blk-core.c
index 473dd69..6c4a425 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -1787,7 +1787,12 @@ static inline void blk_partition_remap(struct bio *bio)
 {
 	struct block_device *bdev = bio->bi_bdev;
 
-	if (bio_sectors(bio) && bdev != bdev->bd_contains) {
+	/*
+	 * Zone reset does not include bi_size so bio_sectors() is always 0.
+	 * Include a test for the reset op code and perform the remap if needed.
+	 */
+	if (bdev != bdev->bd_contains &&
+	    (bio_sectors(bio) || bio_op(bio) == REQ_OP_ZONE_RESET)) {
 		struct hd_struct *p = bdev->bd_part;
 
 		bio->bi_iter.bi_sector += p->start_sect;
-- 
2.10.2

Re: [PATCH v2] Apply blk_partition_remap to REQ_OP_ZONE_RESET

[Jens Axboe]

On 11/21/2016 02:52 PM, Shaun Tancheff wrote:
> If a ZBC device is partitioned and operations are performed on the partition
> the zone information is rebased to the partition, however the zone reset
> is not mapped from the partition to device as are other operations.
>
> This causes the API (report zones / reset zone) to be unbalanced in this
> regard. Checking for the zone reset op code explicitly will balance the
> API.

Much better, thanks. Applied for 4.10.

-- 
Jens Axboe