[PATCH 07/11] scsi: add scsi_host_quiesce()/scsi_host_resume() helper

[Hannes Reinecke <hare@xxxxxxx>]

Add helper functions for quiescing/resuming all devices on a
given scsi host.

Signed-off-by: Hannes Reinecke <hare@xxxxxxx>
---
 drivers/scsi/scsi_lib.c    | 18 ++++++++++++++++++
 include/scsi/scsi_device.h |  2 ++
 2 files changed, 20 insertions(+)

diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 2563b061f56b..771a8352d3e8 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -2630,6 +2630,24 @@ scsi_target_resume(struct scsi_target *starget)
 }
 EXPORT_SYMBOL(scsi_target_resume);
 
+void scsi_host_quiesce(struct Scsi_Host *shost)
+{
+	struct scsi_device *sdev;
+
+	shost_for_each_device(sdev, shost)
+		scsi_device_quiesce(sdev);
+}
+EXPORT_SYMBOL(scsi_host_quiesce);
+
+void scsi_host_resume(struct Scsi_Host *shost)
+{
+	struct scsi_device *sdev;
+
+	shost_for_each_device(sdev, shost)
+		scsi_device_resume(sdev);
+}
+EXPORT_SYMBOL(scsi_host_resume);
+
 /**
  * scsi_internal_device_block_nowait - try to transition to the SDEV_BLOCK state
  * @sdev: device to block
diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h
index 3ed836db5306..2185068ce955 100644
--- a/include/scsi/scsi_device.h
+++ b/include/scsi/scsi_device.h
@@ -420,6 +420,8 @@ extern int scsi_device_quiesce(struct scsi_device *sdev);
 extern void scsi_device_resume(struct scsi_device *sdev);
 extern void scsi_target_quiesce(struct scsi_target *);
 extern void scsi_target_resume(struct scsi_target *);
+extern void scsi_host_quiesce(struct Scsi_Host *);
+extern void scsi_host_resume(struct Scsi_Host *);
 extern void scsi_scan_target(struct device *parent, unsigned int channel,
 			     unsigned int id, u64 lun,
 			     enum scsi_scan_mode rescan);
-- 
2.16.4