diff options
| author | Sebastian Ott <sebott@linux.vnet.ibm.com> | 2009-06-22 12:08:21 +0200 |
|---|---|---|
| committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2009-06-22 12:08:23 +0200 |
| commit | 181d95229b0931ee2ce6aad7348079cbc10e8d05 (patch) | |
| tree | 9962496049dad3c4ed5695d09886d0804be51462 /drivers/s390 | |
| parent | [S390] lockless idle time accounting (diff) | |
| download | linux-181d95229b0931ee2ce6aad7348079cbc10e8d05.tar.xz linux-181d95229b0931ee2ce6aad7348079cbc10e8d05.zip | |
[S390] dasd: fix refcounting in dasd_change_state
To set a dasd online dasd_change_state is called twice. The first
cycle will schedule initial analysis of the device, set the rc to
-EAGAIN and will not touch the device state any more.
The initial analysis will in turn call dasd_change_state to increase
the state to the final DASD_STATE_ONLINE.
If the dasd_change_state on the second thread outruns the other one
both finish with the state set to DASD_STATE_ONLINE and the device
refcount will be decreased by 2.
Fix this by leaving dasd_change_state on rc == -EAGAIN so that the
refcount will always be decreased by 1.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'drivers/s390')
| -rw-r--r-- | drivers/s390/block/dasd.c | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c index 99e71536213a..749836668655 100644 --- a/drivers/s390/block/dasd.c +++ b/drivers/s390/block/dasd.c @@ -470,7 +470,7 @@ static int dasd_decrease_state(struct dasd_device *device) */ static void dasd_change_state(struct dasd_device *device) { - int rc; + int rc; if (device->state == device->target) /* Already where we want to go today... */ @@ -479,8 +479,10 @@ static void dasd_change_state(struct dasd_device *device) rc = dasd_increase_state(device); else rc = dasd_decrease_state(device); - if (rc && rc != -EAGAIN) - device->target = device->state; + if (rc == -EAGAIN) + return; + if (rc) + device->target = device->state; if (device->state == device->target) { wake_up(&dasd_init_waitq); |