[PATCH 6.18 072/752] block: decouple secure erase size limit from discard size limit

Sasha Levin
2026-02-28T17:49:09Z

From: Luke Wang <ziniu.wang_1@nxp.com>

[ Upstream commit ee81212f74a57c5d2b56cf504f40d528dac6faaf ]

Secure erase should use max_secure_erase_sectors instead of being limited
by max_discard_sectors. Separate the handling of REQ_OP_SECURE_ERASE from
REQ_OP_DISCARD to allow each operation to use its own size limit.

Signed-off-by: Luke Wang <ziniu.wang_1@nxp.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
block/blk-merge.c | 21 +++++++++++++++++----
block/blk.h | 6 +++++-
2 files changed, 22 insertions(+), 5 deletions(-)

diff --git a/block/blk-merge.c b/block/blk-merge.c
index 37864c5d287ef..03b61923cf109 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -158,8 +158,9 @@ static struct bio *bio_submit_split(struct bio *bio, int split_sectors)
return bio;
}

-struct bio *bio_split_discard(struct bio *bio, const struct queue_limits *lim,
- unsigned *nsegs)
+static struct bio *__bio_split_discard(struct bio *bio,
+ const struct queue_limits *lim, unsigned *nsegs,
+ unsigned int max_sectors)
{
unsigned int max_discard_sectors, granularity;
sector_t tmp;
@@ -169,8 +170,7 @@ struct bio *bio_split_discard(struct bio *bio, const struct queue_limits *lim,

granularity = max(lim->discard_granularity >> 9, 1U);

- max_discard_sectors =
- min(lim->max_discard_sectors, bio_allowed_max_sectors(lim));
+ max_discard_sectors = min(max_sectors, bio_allowed_max_sectors(lim));
max_discard_sectors -= max_discard_sectors % granularity;
if (unlikely(!max_discard_sectors))
return bio;
@@ -194,6 +194,19 @@ struct bio *bio_split_discard(struct bio *bio, const struct queue_limits *lim,
return bio_submit_split(bio, split_sectors);
}

+struct bio *bio_split_discard(struct bio *bio, const struct queue_limits *lim,
+ unsigned *nsegs)
+{
+ unsigned int max_sectors;
+
+ if (bio_op(bio) == REQ_OP_SECURE_ERASE)
+ max_sectors = lim->max_secure_erase_sectors;
+ else
+ max_sectors = lim->max_discard_sectors;
+
+ return __bio_split_discard(bio, lim, nsegs, max_sectors);
+}
+
static inline unsigned int blk_boundary_sectors(const struct queue_limits *lim,
bool is_atomic)
{
diff --git a/block/blk.h b/block/blk.h
index 37b9b6a95c11c..06dfb5b670179 100644
--- a/block/blk.h
+++ b/block/blk.h
@@ -208,10 +208,14 @@ static inline unsigned int blk_queue_get_max_sectors(struct request *rq)
struct request_queue *q = rq->q;
enum req_op op = req_op(rq);

- if (unlikely(op == REQ_OP_DISCARD || op == REQ_OP_SECURE_ERASE))
+ if (unlikely(op == REQ_OP_DISCARD))
return min(q->limits.max_discard_sectors,
UINT_MAX >> SECTOR_SHIFT);

+ if (unlikely(op == REQ_OP_SECURE_ERASE))
+ return min(q->limits.max_secure_erase_sectors,
+ UINT_MAX >> SECTOR_SHIFT);
+
if (unlikely(op == REQ_OP_WRITE_ZEROES))
return q->limits.max_write_zeroes_sectors;

--
2.51.0