[SCSI] ibmvscsi: prevent scsi commands being sent in invalid state

There is a window where we can be re-enabling an adapter, but
still allow SCSI commands to be sent to the target.  This fix
sets our window (request_limit) to -1 as soon as we know the
adapter is being reenabled, and closes a very teeny tiny
window where we could set the window back to 1 before we
grab a lock.

Signed-off-by: Dave Boutcher <sleddog@us.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

1 files changed, 3 insertions, 1 deletions

diff --git a/drivers/scsi/ibmvscsi/ibmvscsi.c b/drivers/scsi/ibmvscsi/ibmvscsi.c
index eaefeddb2b4..a279d0a8dff 100644
--- a/drivers/scsi/ibmvscsi/ibmvscsi.c
+++ b/drivers/scsi/ibmvscsi/ibmvscsi.c
@@ -853,14 +853,15 @@ static int send_srp_login(struct ibmvscsi_host_data *hostdata)
         login->max_requested_initiator_to_target_iulen = sizeof(union srp_iu);
         login->required_buffer_formats = 0x0006;
         
+        spin_lock_irqsave(hostdata->host->host_lock, flags);
         /* Start out with a request limit of 1, since this is negotiated in
          * the login request we are just sending
          */
         atomic_set(&hostdata->request_limit, 1);
 
-        spin_lock_irqsave(hostdata->host->host_lock, flags);
         rc = ibmvscsi_send_srp_event(evt_struct, hostdata);
         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
+        printk("ibmvscsic: sent SRP login\n");
         return rc;
 };
 
@@ -1179,6 +1180,7 @@ void ibmvscsi_handle_crq(struct viosrp_crq *crq,
                         /* We need to re-setup the interpartition connection */
                         printk(KERN_INFO
                                "ibmvscsi: Re-enabling adapter!\n");
+                        atomic_set(&hostdata->request_limit, -1);
                         purge_requests(hostdata, DID_REQUEUE);
                         if (ibmvscsi_reenable_crq_queue(&hostdata->queue,
                                                         hostdata) == 0)