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authorSebastian Ott <sebott@linux.vnet.ibm.com>2015-09-15 13:11:42 +0200
committerMartin Schwidefsky <schwidefsky@de.ibm.com>2015-10-14 14:32:02 +0200
commit1bc6664bdfb949bc69a08113801e7d6acbf6bc3f (patch)
tree5426526ca602c9394d3501cf15cf61fa5acc2695
parent279b8f9a0f3ea3399764047d487dfdd8f7bc9795 (diff)
s390/cio: use device_lock during cmb activation
Hold the device_lock during [de]activation of the channel measurement block to synchronize concurrent usage of these functions. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
-rw-r--r--arch/s390/include/asm/cmb.h1
-rw-r--r--drivers/s390/cio/cmf.c49
-rw-r--r--drivers/s390/cio/device.c2
3 files changed, 39 insertions, 13 deletions
diff --git a/arch/s390/include/asm/cmb.h b/arch/s390/include/asm/cmb.h
index 806eac12e3bd..ed2630c23f90 100644
--- a/arch/s390/include/asm/cmb.h
+++ b/arch/s390/include/asm/cmb.h
@@ -6,6 +6,7 @@
struct ccw_device;
extern int enable_cmf(struct ccw_device *cdev);
extern int disable_cmf(struct ccw_device *cdev);
+extern int __disable_cmf(struct ccw_device *cdev);
extern u64 cmf_read(struct ccw_device *cdev, int index);
extern int cmf_readall(struct ccw_device *cdev, struct cmbdata *data);
diff --git a/drivers/s390/cio/cmf.c b/drivers/s390/cio/cmf.c
index 3543c486dcdc..5eeb62c3f33a 100644
--- a/drivers/s390/cio/cmf.c
+++ b/drivers/s390/cio/cmf.c
@@ -1226,41 +1226,66 @@ int enable_cmf(struct ccw_device *cdev)
{
int ret;
+ device_lock(&cdev->dev);
ret = cmbops->alloc(cdev);
- cmbops->reset(cdev);
if (ret)
- return ret;
+ goto out;
+ cmbops->reset(cdev);
+ ret = sysfs_create_group(&cdev->dev.kobj, cmbops->attr_group);
+ if (ret) {
+ cmbops->free(cdev);
+ goto out;
+ }
ret = cmbops->set(cdev, 2);
if (ret) {
+ sysfs_remove_group(&cdev->dev.kobj, cmbops->attr_group);
cmbops->free(cdev);
- return ret;
}
- ret = sysfs_create_group(&cdev->dev.kobj, cmbops->attr_group);
- if (!ret)
- return 0;
- cmbops->set(cdev, 0); //FIXME: this can fail
- cmbops->free(cdev);
+out:
+ device_unlock(&cdev->dev);
return ret;
}
/**
- * disable_cmf() - switch off the channel measurement for a specific device
+ * __disable_cmf() - switch off the channel measurement for a specific device
* @cdev: The ccw device to be disabled
*
* Returns %0 for success or a negative error value.
*
* Context:
- * non-atomic
+ * non-atomic, device_lock() held.
*/
-int disable_cmf(struct ccw_device *cdev)
+int __disable_cmf(struct ccw_device *cdev)
{
int ret;
ret = cmbops->set(cdev, 0);
if (ret)
return ret;
- cmbops->free(cdev);
+
sysfs_remove_group(&cdev->dev.kobj, cmbops->attr_group);
+ cmbops->free(cdev);
+
+ return ret;
+}
+
+/**
+ * disable_cmf() - switch off the channel measurement for a specific device
+ * @cdev: The ccw device to be disabled
+ *
+ * Returns %0 for success or a negative error value.
+ *
+ * Context:
+ * non-atomic
+ */
+int disable_cmf(struct ccw_device *cdev)
+{
+ int ret;
+
+ device_lock(&cdev->dev);
+ ret = __disable_cmf(cdev);
+ device_unlock(&cdev->dev);
+
return ret;
}
diff --git a/drivers/s390/cio/device.c b/drivers/s390/cio/device.c
index dfef5e63cb7b..20b92c703944 100644
--- a/drivers/s390/cio/device.c
+++ b/drivers/s390/cio/device.c
@@ -1797,7 +1797,7 @@ static void ccw_device_shutdown(struct device *dev)
cdev = to_ccwdev(dev);
if (cdev->drv && cdev->drv->shutdown)
cdev->drv->shutdown(cdev);
- disable_cmf(cdev);
+ __disable_cmf(cdev);
}
static int ccw_device_pm_prepare(struct device *dev)

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