s390/cio: add helper to query utility strings per given ccw device

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

diff --git a/arch/s390/include/asm/ccwdev.h b/arch/s390/include/asm/ccwdev.h
index 20bce136b2e5b09bcfb170813ee191789a1d2ee4..a29dd430fb405004ae3cf17230e8dccb81a520c7 100644 (file)
--- a/arch/s390/include/asm/ccwdev.h
+++ b/arch/s390/include/asm/ccwdev.h
@@ -231,4 +231,5 @@ int ccw_device_siosl(struct ccw_device *);
 extern void ccw_device_get_schid(struct ccw_device *, struct subchannel_id *);
 
 struct channel_path_desc_fmt0 *ccw_device_get_chp_desc(struct ccw_device *, int);
+u8 *ccw_device_get_util_str(struct ccw_device *cdev, int chp_idx);
 #endif /* _S390_CCWDEV_H_ */

diff --git a/drivers/s390/cio/device_ops.c b/drivers/s390/cio/device_ops.c
index aecfebb74157ecee8d1346b68745be940aff7fd9..4435ae0b3027046cabcb89deb0f0ed806956fcb1 100644 (file)
--- a/drivers/s390/cio/device_ops.c
+++ b/drivers/s390/cio/device_ops.c
@@ -472,6 +472,36 @@ struct channel_path_desc_fmt0 *ccw_device_get_chp_desc(struct ccw_device *cdev,
        return chp_get_chp_desc(chpid);
 }
 
+/**
+ * ccw_device_get_util_str() - return newly allocated utility strings
+ * @cdev: device to obtain the utility strings for
+ * @chp_idx: index of the channel path
+ *
+ * On success return a newly allocated copy of the utility strings
+ * associated with the given channel path. Return %NULL on error.
+ */
+u8 *ccw_device_get_util_str(struct ccw_device *cdev, int chp_idx)
+{
+       struct subchannel *sch = to_subchannel(cdev->dev.parent);
+       struct channel_path *chp;
+       struct chp_id chpid;
+       u8 *util_str;
+
+       chp_id_init(&chpid);
+       chpid.id = sch->schib.pmcw.chpid[chp_idx];
+       chp = chpid_to_chp(chpid);
+
+       util_str = kmalloc(sizeof(chp->desc_fmt3.util_str), GFP_KERNEL);
+       if (!util_str)
+               return NULL;
+
+       mutex_lock(&chp->lock);
+       memcpy(util_str, chp->desc_fmt3.util_str, sizeof(chp->desc_fmt3.util_str));
+       mutex_unlock(&chp->lock);
+
+       return util_str;
+}
+
 /**
  * ccw_device_get_id() - obtain a ccw device id
  * @cdev: device to obtain the id for
@@ -682,3 +712,4 @@ EXPORT_SYMBOL(ccw_device_start_key);
 EXPORT_SYMBOL(ccw_device_get_ciw);
 EXPORT_SYMBOL(ccw_device_get_path_mask);
 EXPORT_SYMBOL_GPL(ccw_device_get_chp_desc);
+EXPORT_SYMBOL_GPL(ccw_device_get_util_str);