FAILED: patch "[PATCH] bcache: fix ioctl in flash device" failed to apply to 4.18-stable tree

[<gregkh@linuxfoundation.org>]

The patch below does not apply to the 4.18-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

>From dd0c91793b7c2658ea32c6b3a2247a8ceca45dc0 Mon Sep 17 00:00:00 2001
From: Tang Junhui <tang.junhui.linux@gmail.com>
Date: Mon, 8 Oct 2018 20:41:10 +0800
Subject: [PATCH] bcache: fix ioctl in flash device

When doing ioctl in flash device, it will call ioctl_dev() in super.c,
then we should not to get cached device since flash only device has
no backend device. This patch just move the jugement dc->io_disable
to cached_dev_ioctl() to make ioctl in flash device correctly.

Fixes: 0f0709e6bfc3c ("bcache: stop bcache device when backing device is offline")
Signed-off-by: Tang Junhui <tang.junhui.linux@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c
index ee15fb039fd0..3bf35914bb57 100644
--- a/drivers/md/bcache/request.c
+++ b/drivers/md/bcache/request.c
@@ -1218,6 +1218,9 @@ static int cached_dev_ioctl(struct bcache_device *d, fmode_t mode,
 {
 	struct cached_dev *dc = container_of(d, struct cached_dev, disk);
 
+	if (dc->io_disable)
+		return -EIO;
+
 	return __blkdev_driver_ioctl(dc->bdev, mode, cmd, arg);
 }
 
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index 5fd1466b34e4..9de6695195bf 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -648,10 +648,6 @@ static int ioctl_dev(struct block_device *b, fmode_t mode,
 		     unsigned int cmd, unsigned long arg)
 {
 	struct bcache_device *d = b->bd_disk->private_data;
-	struct cached_dev *dc = container_of(d, struct cached_dev, disk);
-
-	if (dc->io_disable)
-		return -EIO;
 
 	return d->ioctl(d, mode, cmd, arg);
 }