linux-kernel - [PATCH 01/16] block: make blkdev_nr_zones and blk_queue_zone

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Wed, 27 Apr 2022 18:02:40 +0200
From:   Pankaj Raghav <p.raghav@...sung.com>
To:     jaegeuk@...nel.org, axboe@...nel.dk, snitzer@...nel.org,
        hch@....de, mcgrof@...nel.org, naohiro.aota@....com,
        sagi@...mberg.me, damien.lemoal@...nsource.wdc.com,
        dsterba@...e.com, johannes.thumshirn@....com
Cc:     linux-kernel@...r.kernel.org, linux-btrfs@...r.kernel.org,
        clm@...com, gost.dev@...sung.com, chao@...nel.org,
        linux-f2fs-devel@...ts.sourceforge.net, josef@...icpanda.com,
        jonathan.derrick@...ux.dev, agk@...hat.com, kbusch@...nel.org,
        kch@...dia.com, linux-nvme@...ts.infradead.org,
        dm-devel@...hat.com, bvanassche@....org, jiangbo.365@...edance.com,
        linux-fsdevel@...r.kernel.org, matias.bjorling@....com,
        linux-block@...r.kernel.org, Pankaj Raghav <p.raghav@...sung.com>
Subject: [PATCH 01/16] block: make blkdev_nr_zones and blk_queue_zone_no
 generic for npo2 zsze

Adapt blkdev_nr_zones and blk_queue_zone_no function so that it can
also work for non-power-of-2 zone sizes.

As the existing deployments of zoned devices had power-of-2
assumption, power-of-2 optimized calculation is kept for those devices.

There are no direct hot paths modified and the changes just
introduce one new branch per call.

Reviewed-by: Luis Chamberlain <mcgrof@...nel.org>
Signed-off-by: Pankaj Raghav <p.raghav@...sung.com>
---
 block/blk-zoned.c      | 8 +++++++-
 include/linux/blkdev.h | 8 +++++++-
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/block/blk-zoned.c b/block/blk-zoned.c
index 38cd840d8838..1dff4a8bd51d 100644
--- a/block/blk-zoned.c
+++ b/block/blk-zoned.c
@@ -117,10 +117,16 @@ EXPORT_SYMBOL_GPL(__blk_req_zone_write_unlock);
 unsigned int blkdev_nr_zones(struct gendisk *disk)
 {
 	sector_t zone_sectors = blk_queue_zone_sectors(disk->queue);
+	sector_t capacity = get_capacity(disk);
 
 	if (!blk_queue_is_zoned(disk->queue))
 		return 0;
-	return (get_capacity(disk) + zone_sectors - 1) >> ilog2(zone_sectors);
+
+	if (is_power_of_2(zone_sectors))
+		return (capacity + zone_sectors - 1) >>
+		       ilog2(zone_sectors);
+
+	return div64_u64(capacity + zone_sectors - 1, zone_sectors);
 }
 EXPORT_SYMBOL_GPL(blkdev_nr_zones);
 
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 60d016138997..c4e4c7071b7b 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -665,9 +665,15 @@ static inline unsigned int blk_queue_nr_zones(struct request_queue *q)
 static inline unsigned int blk_queue_zone_no(struct request_queue *q,
 					     sector_t sector)
 {
+	sector_t zone_sectors = blk_queue_zone_sectors(q);
+
 	if (!blk_queue_is_zoned(q))
 		return 0;
-	return sector >> ilog2(q->limits.chunk_sectors);
+
+	if (is_power_of_2(zone_sectors))
+		return sector >> ilog2(zone_sectors);
+
+	return div64_u64(sector, zone_sectors);
 }
 
 static inline bool blk_queue_zone_is_seq(struct request_queue *q,
-- 
2.25.1