[PATCH v8 04/10] Remove offline devices when removing a host

[Bart Van Assche <bvanassche@acm.org>]

__scsi_remove_device() incorrectly skips devices that are visible
and offline. Such devices get skipped because scsi_device_set_state()
refuses the transition from SDEV_OFFLINE into SDEV_CANCEL. Make
sure that these devices get removed by changing their device state
into SDEV_DEL at the start of __scsi_remove_device(). Also, avoid
that __scsi_remove_device() gets called a second time by
scsi_forget_host() for devices that are in state SDEV_CANCEL.

Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Cc: James Bottomley <JBottomley@Parallels.com>
Cc: Mike Christie <michaelc@cs.wisc.edu>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Tejun Heo <tj@kernel.org>
---
 drivers/scsi/scsi_scan.c  |    2 +-
 drivers/scsi/scsi_sysfs.c |    4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c
index 3e58b22..0612fba 100644
--- a/drivers/scsi/scsi_scan.c
+++ b/drivers/scsi/scsi_scan.c
@@ -1889,7 +1889,7 @@ void scsi_forget_host(struct Scsi_Host *shost)
  restart:
 	spin_lock_irqsave(shost->host_lock, flags);
 	list_for_each_entry(sdev, &shost->__devices, siblings) {
-		if (sdev->sdev_state == SDEV_DEL)
+		if (scsi_device_being_removed(sdev))
 			continue;
 		spin_unlock_irqrestore(shost->host_lock, flags);
 		__scsi_remove_device(sdev);
diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c
index 34f1b39..5e0c769 100644
--- a/drivers/scsi/scsi_sysfs.c
+++ b/drivers/scsi/scsi_sysfs.c
@@ -956,8 +956,8 @@ void __scsi_remove_device(struct scsi_device *sdev)
 	unsigned long flags;
 
 	if (sdev->is_visible) {
-		if (scsi_device_set_state(sdev, SDEV_CANCEL) != 0)
-			return;
+		WARN_ON_ONCE(scsi_device_set_state(sdev, SDEV_CANCEL) != 0 &&
+			     scsi_device_set_state(sdev, SDEV_DEL) != 0);
 
 		bsg_unregister_queue(sdev->request_queue);
 		device_unregister(&sdev->sdev_dev);
-- 
1.7.10.4