[C][PATCH 1/2] bcache: fix ioctl in flash device

[Mauricio Faria de Oliveira]

From: Tang Junhui <tang.junhui.linux at gmail.com>

BugLink: https://bugs.launchpad.net/bugs/1829563

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 at gmail.com>
Cc: stable at vger.kernel.org
Signed-off-by: Coly Li <colyli at suse.de>
Signed-off-by: Jens Axboe <axboe at kernel.dk>
(backported from commit dd0c91793b7c2658ea32c6b3a2247a8ceca45dc0)
[mfo: backport: request.c/hunk 1: insert blank line, refresh one context line.]
Signed-off-by: Mauricio Faria de Oliveira <mfo at canonical.com>
---
 drivers/md/bcache/request.c | 4 ++++
 drivers/md/bcache/super.c   | 4 ----
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c
index 9d2fa1359029..d451f2df150b 100644
--- a/drivers/md/bcache/request.c
+++ b/drivers/md/bcache/request.c
@@ -1156,6 +1156,10 @@ static int cached_dev_ioctl(struct bcache_device *d, fmode_t mode,
 			    unsigned int cmd, unsigned long arg)
 {
 	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 27c27c00c052..f09bf4a430fb 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -636,10 +636,6 @@ 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);
 }
-- 
2.17.1