[PATCH] s390: dasd ioctl never returns

The dasd state machine is not designed to enable an unformatted device, since
'unformatted' is a final state.  The BIODASDENABLE ioctl calls
dasd_enable_device() which never returns if the device is in this special
state.  Return -EPERM in dasd_increase_state for unformatted devices to make
dasd_enable_device terminate.  Note: To get such an unformatted device online
it has to be re-analyzed.  This means that the device needs to be disabled
prior to re-enablement.

Signed-off-by: Horst Hummel <horst.hummel@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 5 insertions, 0 deletions

diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c
index a3bfebcf31e..cfb1fff3787 100644
--- a/drivers/s390/block/dasd.c
+++ b/drivers/s390/block/dasd.c
@@ -315,6 +315,11 @@ dasd_increase_state(struct dasd_device *device)
                 rc = dasd_state_basic_to_ready(device);
 
         if (!rc &&
+            device->state == DASD_STATE_UNFMT &&
+            device->target > DASD_STATE_UNFMT)
+                rc = -EPERM;
+
+        if (!rc &&
             device->state == DASD_STATE_READY &&
             device->target >= DASD_STATE_ONLINE)
                 rc = dasd_state_ready_to_online(device);