[SCSI] fix oops on usb storage device disconnect

We fix the oops by enforcing the host state model.  There have also
been two extra states added: SHOST_CANCEL_RECOVERY and
SHOST_DEL_RECOVERY so we can take the model through host removal while
the recovery thread is active.

Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

1 files changed, 9 insertions, 0 deletions

diff --git a/include/scsi/scsi_host.h b/include/scsi/scsi_host.h
index 916144be208b..540369ff815c 100644
--- a/include/scsi/scsi_host.h
+++ b/include/scsi/scsi_host.h
@@ -439,6 +439,8 @@ enum scsi_host_state {
         SHOST_CANCEL,
         SHOST_DEL,
         SHOST_RECOVERY,
+        SHOST_CANCEL_RECOVERY,
+        SHOST_DEL_RECOVERY,
 };
 
 struct Scsi_Host {
@@ -621,6 +623,13 @@ static inline struct Scsi_Host *dev_to_shost(struct device *dev)
         return container_of(dev, struct Scsi_Host, shost_gendev);
 }
 
+static inline int scsi_host_in_recovery(struct Scsi_Host *shost)
+{
+        return shost->shost_state == SHOST_RECOVERY ||
+                shost->shost_state == SHOST_CANCEL_RECOVERY ||
+                shost->shost_state == SHOST_DEL_RECOVERY;
+}
+
 extern int scsi_queue_work(struct Scsi_Host *, struct work_struct *);
 extern void scsi_flush_work(struct Scsi_Host *);