[S390] cio: fix sanity checks in device_ops.

Some sanity checks in device_ops.c test the output of container_of
macros to be !NULL. Test the input parameters instead.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 8 insertions, 16 deletions

diff --git a/drivers/s390/cio/device_ops.c b/drivers/s390/cio/device_ops.c
index 151754d54745..bf0a24af39a0 100644
--- a/drivers/s390/cio/device_ops.c
+++ b/drivers/s390/cio/device_ops.c
@@ -114,7 +114,7 @@ int ccw_device_clear(struct ccw_device *cdev, unsigned long intparm)
         struct subchannel *sch;
         int ret;
 
-        if (!cdev)
+        if (!cdev || !cdev->dev.parent)
                 return -ENODEV;
         if (cdev->private->state == DEV_STATE_NOT_OPER)
                 return -ENODEV;
@@ -122,8 +122,6 @@ int ccw_device_clear(struct ccw_device *cdev, unsigned long intparm)
             cdev->private->state != DEV_STATE_W4SENSE)
                 return -EINVAL;
         sch = to_subchannel(cdev->dev.parent);
-        if (!sch)
-                return -ENODEV;
         ret = cio_clear(sch);
         if (ret == 0)
                 cdev->private->intparm = intparm;
@@ -161,11 +159,9 @@ int ccw_device_start_key(struct ccw_device *cdev, struct ccw1 *cpa,
         struct subchannel *sch;
         int ret;
 
-        if (!cdev)
+        if (!cdev || !cdev->dev.parent)
                 return -ENODEV;
         sch = to_subchannel(cdev->dev.parent);
-        if (!sch)
-                return -ENODEV;
         if (cdev->private->state == DEV_STATE_NOT_OPER)
                 return -ENODEV;
         if (cdev->private->state == DEV_STATE_VERIFY ||
@@ -339,7 +335,7 @@ int ccw_device_halt(struct ccw_device *cdev, unsigned long intparm)
         struct subchannel *sch;
         int ret;
 
-        if (!cdev)
+        if (!cdev || !cdev->dev.parent)
                 return -ENODEV;
         if (cdev->private->state == DEV_STATE_NOT_OPER)
                 return -ENODEV;
@@ -347,8 +343,6 @@ int ccw_device_halt(struct ccw_device *cdev, unsigned long intparm)
             cdev->private->state != DEV_STATE_W4SENSE)
                 return -EINVAL;
         sch = to_subchannel(cdev->dev.parent);
-        if (!sch)
-                return -ENODEV;
         ret = cio_halt(sch);
         if (ret == 0)
                 cdev->private->intparm = intparm;
@@ -372,11 +366,9 @@ int ccw_device_resume(struct ccw_device *cdev)
 {
         struct subchannel *sch;
 
-        if (!cdev)
+        if (!cdev || !cdev->dev.parent)
                 return -ENODEV;
         sch = to_subchannel(cdev->dev.parent);
-        if (!sch)
-                return -ENODEV;
         if (cdev->private->state == DEV_STATE_NOT_OPER)
                 return -ENODEV;
         if (cdev->private->state != DEV_STATE_ONLINE ||
@@ -471,11 +463,11 @@ __u8 ccw_device_get_path_mask(struct ccw_device *cdev)
 {
         struct subchannel *sch;
 
-        sch = to_subchannel(cdev->dev.parent);
-        if (!sch)
+        if (!cdev->dev.parent)
                 return 0;
-        else
-                return sch->lpm;
+
+        sch = to_subchannel(cdev->dev.parent);
+        return sch->lpm;
 }
 
 /*