From: Jan Höppner hoeppner@linux.vnet.ibm.com
[ Upstream commit b487a914f853545842a0899329b6b72fe56c4081 ]
We have two flags, DASD_FLAG_DEVICE_RO and DASD_FEATURE_READONLY, that tell us whether a device is read-only. DASD_FLAG_DEVICE_RO is set when a device is attached as read-only to z/VM and DASD_FEATURE_READONLY is set when either the corresponding kernel parameter is configured, or the read-only state is changed via sysfs. This is valuable information in any case. However, only the feature flag is being checked at the moment when we display the current state.
Fix this by checking both flags.
Reviewed-by: Stefan Haberland sth@linux.vnet.ibm.com Signed-off-by: Jan Höppner hoeppner@linux.vnet.ibm.com Signed-off-by: Martin Schwidefsky schwidefsky@de.ibm.com Signed-off-by: Sasha Levin alexander.levin@microsoft.com --- drivers/s390/block/dasd_devmap.c | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-)
diff --git a/drivers/s390/block/dasd_devmap.c b/drivers/s390/block/dasd_devmap.c index 15a1a70cace9..8c4bcbd491f3 100644 --- a/drivers/s390/block/dasd_devmap.c +++ b/drivers/s390/block/dasd_devmap.c @@ -757,13 +757,22 @@ static ssize_t dasd_ro_show(struct device *dev, struct device_attribute *attr, char *buf) { struct dasd_devmap *devmap; - int ro_flag; + struct dasd_device *device; + int ro_flag = 0;
devmap = dasd_find_busid(dev_name(dev)); - if (!IS_ERR(devmap)) - ro_flag = (devmap->features & DASD_FEATURE_READONLY) != 0; - else - ro_flag = (DASD_FEATURE_DEFAULT & DASD_FEATURE_READONLY) != 0; + if (IS_ERR(devmap)) + goto out; + + ro_flag = !!(devmap->features & DASD_FEATURE_READONLY); + + spin_lock(&dasd_devmap_lock); + device = devmap->device; + if (device) + ro_flag |= test_bit(DASD_FLAG_DEVICE_RO, &device->flags); + spin_unlock(&dasd_devmap_lock); + +out: return snprintf(buf, PAGE_SIZE, ro_flag ? "1\n" : "0\n"); }