3 files changed, 33 insertions, 4 deletions

diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c
index dc6131e6a1b..5f84a148eb1 100644
--- a/drivers/scsi/scsi_error.c
+++ b/drivers/scsi/scsi_error.c
@@ -1812,7 +1812,7 @@ int scsi_error_handler(void *data)
 		 * what we need to do to get it up and online again (if we can).
 		 * If we fail, we end up taking the thing offline.
 		 */
-		if (scsi_autopm_get_host(shost) != 0) {
+		if (!shost->eh_noresume && scsi_autopm_get_host(shost) != 0) {
 			SCSI_LOG_ERROR_RECOVERY(1,
 				printk(KERN_ERR "Error handler scsi_eh_%d "
 						"unable to autoresume\n",
@@ -1833,7 +1833,8 @@ int scsi_error_handler(void *data)
 		 * which are still online.
 		 */
 		scsi_restart_operations(shost);
-		scsi_autopm_put_host(shost);
+		if (!shost->eh_noresume)
+			scsi_autopm_put_host(shost);
 		set_current_state(TASK_INTERRUPTIBLE);
 	}
 	__set_current_state(TASK_RUNNING);
diff --git a/drivers/scsi/scsi_pm.c b/drivers/scsi/scsi_pm.c
index d329f8b12e2..bf8bf79e6a1 100644
--- a/drivers/scsi/scsi_pm.c
+++ b/drivers/scsi/scsi_pm.c
@@ -49,8 +49,22 @@ static int scsi_bus_suspend_common(struct device *dev, pm_message_t msg)
 {
 	int err = 0;
 
-	if (scsi_is_sdev_device(dev))
+	if (scsi_is_sdev_device(dev)) {
+		/*
+		 * sd is the only high-level SCSI driver to implement runtime
+		 * PM, and sd treats runtime suspend, system suspend, and
+		 * system hibernate identically (but not system freeze).
+		 */
+		if (pm_runtime_suspended(dev)) {
+			if (msg.event == PM_EVENT_SUSPEND ||
+			    msg.event == PM_EVENT_HIBERNATE)
+				return 0;	/* already suspended */
+
+			/* wake up device so that FREEZE will succeed */
+			pm_runtime_resume(dev);
+		}
 		err = scsi_dev_type_suspend(dev, msg);
+	}
 	return err;
 }
 
@@ -58,8 +72,17 @@ static int scsi_bus_resume_common(struct device *dev)
 {
 	int err = 0;
 
-	if (scsi_is_sdev_device(dev))
+	if (scsi_is_sdev_device(dev)) {
+		/*
+		 * Parent device may have runtime suspended as soon as
+		 * it is woken up during the system resume.
+		 *
+		 * Resume it on behalf of child.
+		 */
+		pm_runtime_get_sync(dev->parent);
 		err = scsi_dev_type_resume(dev);
+		pm_runtime_put_sync(dev->parent);
+	}
 
 	if (err == 0) {
 		pm_runtime_disable(dev);
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index fa3a5918009..7b3f8075e2a 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -50,6 +50,7 @@
 #include <linux/string_helpers.h>
 #include <linux/async.h>
 #include <linux/slab.h>
+#include <linux/pm_runtime.h>
 #include <asm/uaccess.h>
 #include <asm/unaligned.h>
 
@@ -2741,6 +2742,9 @@ static void sd_shutdown(struct device *dev)
 	if (!sdkp)
 		return;         /* this can happen */
 
+	if (pm_runtime_suspended(dev))
+		goto exit;
+
 	if (sdkp->WCE) {
 		sd_printk(KERN_NOTICE, sdkp, "Synchronizing SCSI cache\n");
 		sd_sync_cache(sdkp);
@@ -2751,6 +2755,7 @@ static void sd_shutdown(struct device *dev)
 		sd_start_stop_device(sdkp, 0);
 	}
 
+exit:
 	scsi_disk_put(sdkp);
 }