[SCSI] Block I/O while SG reset operation in progress - the midlayer patch

The scsi midlayer portion of the patch

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

2 files changed, 27 insertions, 1 deletions

diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c
index 6a7a60fc0a4e..6683d596234a 100644
--- a/drivers/scsi/scsi_error.c
+++ b/drivers/scsi/scsi_error.c
@@ -1672,7 +1672,9 @@ int
 scsi_reset_provider(struct scsi_device *dev, int flag)
 {
         struct scsi_cmnd *scmd = scsi_get_command(dev, GFP_KERNEL);
+        struct Scsi_Host *shost = dev->host;
         struct request req;
+        unsigned long flags;
         int rtn;
 
         scmd->request = &req;
@@ -1699,6 +1701,10 @@ scsi_reset_provider(struct scsi_device *dev, int flag)
          */
         scmd->pid                       = 0;
 
+        spin_lock_irqsave(shost->host_lock, flags);
+        shost->tmf_in_progress = 1;
+        spin_unlock_irqrestore(shost->host_lock, flags);
+
         switch (flag) {
         case SCSI_TRY_RESET_DEVICE:
                 rtn = scsi_try_bus_device_reset(scmd);
@@ -1717,6 +1723,22 @@ scsi_reset_provider(struct scsi_device *dev, int flag)
                 rtn = FAILED;
         }
 
+        spin_lock_irqsave(shost->host_lock, flags);
+        shost->tmf_in_progress = 0;
+        spin_unlock_irqrestore(shost->host_lock, flags);
+
+        /*
+         * be sure to wake up anyone who was sleeping or had their queue
+         * suspended while we performed the TMF.
+         */
+        SCSI_LOG_ERROR_RECOVERY(3,
+                printk("%s: waking up host to restart after TMF\n",
+                __FUNCTION__));
+
+        wake_up(&shost->host_wait);
+
+        scsi_run_host_queues(shost);
+
         scsi_next_command(scmd);
         return rtn;
 }
diff --git a/include/scsi/scsi_host.h b/include/scsi/scsi_host.h
index a42efd6e4be8..b3dd90f3e858 100644
--- a/include/scsi/scsi_host.h
+++ b/include/scsi/scsi_host.h
@@ -542,6 +542,9 @@ struct Scsi_Host {
          */
         unsigned ordered_tag:1;
 
+        /* task mgmt function in progress */
+        unsigned tmf_in_progress:1;
+
         /*
          * Optional work queue to be utilized by the transport
          */
@@ -619,7 +622,8 @@ 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;
+                shost->shost_state == SHOST_DEL_RECOVERY ||
+                shost->tmf_in_progress;
 }
 
 extern int scsi_queue_work(struct Scsi_Host *, struct work_struct *);