Re: [PATCH 1/6] md: switch to ->check_events for media change notifications

From: Matthew Wilcox <willy@infradead.org>
To: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Cc: Christoph Hellwig <hch@lst.de>, Jens Axboe <axboe@kernel.dk>,
	Song Liu <song@kernel.org>, Ulf Hansson <ulf.hansson@linaro.org>,
	linux-kernel@vger.kernel.org, linux-xtensa@linux-xtensa.org,
	linux-block@vger.kernel.org, linux-raid@vger.kernel.org,
	linux-mmc@vger.kernel.org, linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH 1/6] md: switch to ->check_events for media change notifications
Date: Wed, 8 Jul 2020 14:23:38 +0100	[thread overview]
Message-ID: <20200708132338.GO25523@casper.infradead.org> (raw)
In-Reply-To: <09cd4827-52ae-0e7c-c3d3-e9a6cd27ff2b@cloud.ionos.com>

On Wed, Jul 08, 2020 at 03:17:31PM +0200, Guoqing Jiang wrote:
> On 7/8/20 2:25 PM, Christoph Hellwig wrote:
> > -static int md_media_changed(struct gendisk *disk)
> > -{
> > -	struct mddev *mddev = disk->private_data;
> > -
> > -	return mddev->changed;
> > -}
> 
> Maybe we can remove "changed" from struct mddev since no one reads it
> after the change.

You missed this hunk:

+static unsigned int md_check_events(struct gendisk *disk, unsigned int clearing)
 {
        struct mddev *mddev = disk->private_data;
+	unsigned int ret = 0;

+	if (mddev->changed)
+               ret = DISK_EVENT_MEDIA_CHANGE;
        mddev->changed = 0;
-	return 0;
+	return ret;
 }