[S390] dasd: automatic recognition of read-only devices
In z/VM it is possible to attach a device as read-only. To prevent
unintentional write requests and subsequent I/O errors, we can detect
this configuration using the z/VM DIAG 210 interface and set the
respective linux block device to read-only as well.
Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/drivers/s390/block/dasd_int.h b/drivers/s390/block/dasd_int.h
index ed73ce5..a91d4a9 100644
--- a/drivers/s390/block/dasd_int.h
+++ b/drivers/s390/block/dasd_int.h
@@ -436,6 +436,10 @@
#define DASD_FLAG_OFFLINE 3 /* device is in offline processing */
#define DASD_FLAG_EER_SNSS 4 /* A SNSS is required */
#define DASD_FLAG_EER_IN_USE 5 /* A SNSS request is running */
+#define DASD_FLAG_DEVICE_RO 6 /* The device itself is read-only. Don't
+ * confuse this with the user specified
+ * read-only feature.
+ */
void dasd_put_device_wake(struct dasd_device *);
@@ -609,6 +613,9 @@
void dasd_device_set_stop_bits(struct dasd_device *, int);
void dasd_device_remove_stop_bits(struct dasd_device *, int);
+int dasd_device_is_ro(struct dasd_device *);
+
+
/* externals in dasd_devmap.c */
extern int dasd_max_devindex;
extern int dasd_probeonly;