[SCSI] ibmvfc: Fix soft lockup on resume

This fixes a softlockup seen on resume. During resume, the CRQ
must be reenabled. However, the H_ENABLE_CRQ hcall used to do
this may return H_BUSY or H_LONG_BUSY. When this happens, the
caller is expected to retry later. Normally the H_ENABLE_CRQ
succeeds relatively soon. However, we have seen cases where
this can take long enough to see softlockup warnings.
This patch changes a simple loop, which was causing the
softlockup, to a loop at task level which sleeps between
retries rather than simply spinning.

Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

1 files changed, 2 insertions, 0 deletions

diff --git a/drivers/scsi/ibmvscsi/ibmvfc.h b/drivers/scsi/ibmvscsi/ibmvfc.h
index 7e9742764e4b..2010d73aca81 100644
--- a/drivers/scsi/ibmvscsi/ibmvfc.h
+++ b/drivers/scsi/ibmvscsi/ibmvfc.h
@@ -649,6 +649,8 @@ struct ibmvfc_event_pool {
 
 enum ibmvfc_host_action {
         IBMVFC_HOST_ACTION_NONE = 0,
+        IBMVFC_HOST_ACTION_RESET,
+        IBMVFC_HOST_ACTION_REENABLE,
         IBMVFC_HOST_ACTION_LOGO,
         IBMVFC_HOST_ACTION_LOGO_WAIT,
         IBMVFC_HOST_ACTION_INIT,