[SCSI] ibmvscsi: Fix softlockup 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. 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, 4 insertions, 0 deletions

diff --git a/drivers/scsi/ibmvscsi/ibmvscsi.h b/drivers/scsi/ibmvscsi/ibmvscsi.h
index 9cb7c6a773e1..02197a2b22b9 100644
--- a/drivers/scsi/ibmvscsi/ibmvscsi.h
+++ b/drivers/scsi/ibmvscsi/ibmvscsi.h
@@ -91,12 +91,16 @@ struct event_pool {
 struct ibmvscsi_host_data {
         atomic_t request_limit;
         int client_migrated;
+        int reset_crq;
+        int reenable_crq;
         struct device *dev;
         struct event_pool pool;
         struct crq_queue queue;
         struct tasklet_struct srp_task;
         struct list_head sent;
         struct Scsi_Host *host;
+        struct task_struct *work_thread;
+        wait_queue_head_t work_wait_q;
         struct mad_adapter_info_data madapter_info;
         struct capabilities caps;
         dma_addr_t caps_addr;