[PATCH v3 5/6] block: increment sequence number

From: Matteo Croce <mcroce@linux.microsoft.com>
To: linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org,
	Jens Axboe <axboe@kernel.dk>
Cc: linux-kernel@vger.kernel.org,
	"Lennart Poettering" <lennart@poettering.net>,
	"Luca Boccassi" <bluca@debian.org>,
	"Alexander Viro" <viro@zeniv.linux.org.uk>,
	"Damien Le Moal" <damien.lemoal@wdc.com>,
	"Tejun Heo" <tj@kernel.org>,
	"Javier González" <javier@javigon.com>,
	"Niklas Cassel" <niklas.cassel@wdc.com>,
	"Johannes Thumshirn" <johannes.thumshirn@wdc.com>,
	"Hannes Reinecke" <hare@suse.de>,
	"Matthew Wilcox" <willy@infradead.org>,
	"Christoph Hellwig" <hch@infradead.org>,
	JeffleXu <jefflexu@linux.alibaba.com>
Subject: [PATCH v3 5/6] block: increment sequence number
Date: Wed, 23 Jun 2021 12:58:57 +0200	[thread overview]
Message-ID: <20210623105858.6978-6-mcroce@linux.microsoft.com> (raw)
In-Reply-To: <20210623105858.6978-1-mcroce@linux.microsoft.com>

From: Matteo Croce <mcroce@microsoft.com>

Increment the disk sequence number when the media has changed,
i.e. on DISK_EVENT_MEDIA_CHANGE event.

    $ cat /sys/class/block/sr0/diskseq
    12
    $ eject
    $ cat /sys/class/block/sr0/diskseq
    22

Signed-off-by: Matteo Croce <mcroce@microsoft.com>
---
 block/genhd.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/block/genhd.c b/block/genhd.c
index 768d8d5d1eca..9d58e0ea18ae 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -1657,6 +1657,9 @@ static void disk_check_events(struct disk_events *ev,
 
 	spin_unlock_irq(&ev->lock);
 
+	if (events & DISK_EVENT_MEDIA_CHANGE)
+		inc_diskseq(disk);
+
 	/*
 	 * Tell userland about new events.  Only the events listed in
 	 * @disk->events are reported, and only if DISK_EVENT_FLAG_UEVENT
-- 
2.31.1

