From 1adfc5e4136f5967d591c399aff95b3b035f16b7 Mon Sep 17 00:00:00 2001
From: Ming Lei <ming.lei@redhat.com>
Date: Mon, 29 Oct 2018 20:57:17 +0800
Subject: [PATCH] block: make sure discard bio is aligned with logical block
size
Git-commit: 1adfc5e4136f5967d591c399aff95b3b035f16b7
Patch-mainline: v4.20-rc2
References: bsc#1104967,FATE#325924
Obviously the created discard bio has to be aligned with logical block size.
This patch introduces the helper of bio_allowed_max_sectors() for
this purpose.
Cc: stable@vger.kernel.org
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Xiao Ni <xni@redhat.com>
Cc: Mariusz Dabrowski <mariusz.dabrowski@intel.com>
Fixes: 744889b7cbb56a6 ("block: don't deal with discard limit in blkdev_issue_discard()")
Fixes: a22c4d7e34402cc ("block: re-add discard_granularity and alignment checks")
Reported-by: Rui Salvaterra <rsalvaterra@gmail.com>
Tested-by: Rui Salvaterra <rsalvaterra@gmail.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Acked-by: Hannes Reinecke <hare@suse.com>
---
block/blk-lib.c | 3 +--
block/blk-merge.c | 3 ++-
block/blk.h | 10 ++++++++++
3 files changed, 13 insertions(+), 3 deletions(-)
--- a/block/blk-lib.c
+++ b/block/blk-lib.c
@@ -54,8 +54,7 @@ int __blkdev_issue_discard(struct block_
if (!req_sects)
goto fail;
- if (req_sects > UINT_MAX >> 9)
- req_sects = UINT_MAX >> 9;
+ req_sects = min(req_sects, bio_allowed_max_sectors(q));
end_sect = sector + req_sects;
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -26,7 +26,8 @@ static struct bio *blk_bio_discard_split
/* Zero-sector (unknown) and one-sector granularities are the same. */
granularity = max(q->limits.discard_granularity >> 9, 1U);
- max_discard_sectors = min(q->limits.max_discard_sectors, UINT_MAX >> 9);
+ max_discard_sectors = min(q->limits.max_discard_sectors,
+ bio_allowed_max_sectors(q));
max_discard_sectors -= max_discard_sectors % granularity;
if (unlikely(!max_discard_sectors)) {
--- a/block/blk.h
+++ b/block/blk.h
@@ -278,6 +278,16 @@ static inline void req_set_nomerge(struc
return rq->__deadline & ~0x1UL;
}
+/*
+ * The max size one bio can handle is UINT_MAX becasue bvec_iter.bi_size
+ * is defined as 'unsigned int', meantime it has to aligned to with logical
+ * block size which is the minimum accepted unit by hardware.
+ */
+static inline unsigned int bio_allowed_max_sectors(struct request_queue *q)
+{
+ return round_down(UINT_MAX, queue_logical_block_size(q)) >> 9;
+}
+
/*
* Internal io_context interface
*/