s390/ccwgroup: tie a ccwgroup driver to its ccw driver

When grouping devices, the ccwgroup core only checks whether all of the
devices are bound to the same ccw_driver. It has no means of checking
if the requesting ccwgroup driver actually supports this device type.
qeth implements its own device matching in qeth_core_probe_device(),
while ctcm and lcs currently have no sanity-checking at all.

Enable ccwgroup drivers to optionally defer the device type checking to
the ccwgroup core, by specifying their supported ccw_driver.
This allows us drop the device type matching from qeth, and improves
the robustness of ctcm and lcs.

Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Acked-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

diff --git a/arch/s390/include/asm/ccwgroup.h b/arch/s390/include/asm/ccwgroup.h
index 057ce0c..6d50e86 100644 (file)
--- a/arch/s390/include/asm/ccwgroup.h
+++ b/arch/s390/include/asm/ccwgroup.h
@@ -41,6 +41,7 @@ struct ccwgroup_device {
  * @thaw: undo work done in @freeze
  * @restore: callback for restoring after hibernation
  * @driver: embedded driver structure
+ * @ccw_driver: supported ccw_driver (optional)
  */
 struct ccwgroup_driver {
        int (*setup) (struct ccwgroup_device *);
@@ -55,6 +56,7 @@ struct ccwgroup_driver {
        int (*restore)(struct ccwgroup_device *);
 
        struct device_driver driver;
+       struct ccw_driver *ccw_driver;
 };
 
 extern int  ccwgroup_driver_register   (struct ccwgroup_driver *cdriver);

diff --git a/drivers/s390/cio/ccwgroup.c b/drivers/s390/cio/ccwgroup.c
index 34b9ad6..e2f7b6e 100644 (file)
--- a/drivers/s390/cio/ccwgroup.c
+++ b/drivers/s390/cio/ccwgroup.c
@@ -373,6 +373,12 @@ int ccwgroup_create_dev(struct device *parent, struct ccwgroup_driver *gdrv,
                rc = -EINVAL;
                goto error;
        }
+       /* Check if the devices are bound to the required ccw driver. */
+       if (gdev->count && gdrv && gdrv->ccw_driver &&
+           gdev->cdev[0]->drv != gdrv->ccw_driver) {
+               rc = -EINVAL;
+               goto error;
+       }
 
        dev_set_name(&gdev->dev, "%s", dev_name(&gdev->cdev[0]->dev));
        gdev->dev.groups = ccwgroup_attr_groups;

diff --git a/drivers/s390/net/ctcm_main.c b/drivers/s390/net/ctcm_main.c
index 26363e0..be9f172 100644 (file)
--- a/drivers/s390/net/ctcm_main.c
+++ b/drivers/s390/net/ctcm_main.c
@@ -1761,6 +1761,7 @@ static struct ccwgroup_driver ctcm_group_driver = {
                .owner  = THIS_MODULE,
                .name   = CTC_DRIVER_NAME,
        },
+       .ccw_driver  = &ctcm_ccw_driver,
        .setup       = ctcm_probe_device,
        .remove      = ctcm_remove_device,
        .set_online  = ctcm_new_device,

diff --git a/drivers/s390/net/lcs.c b/drivers/s390/net/lcs.c
index d01b5c2..0bf7b73 100644 (file)
--- a/drivers/s390/net/lcs.c
+++ b/drivers/s390/net/lcs.c
@@ -2396,6 +2396,7 @@ static struct ccwgroup_driver lcs_group_driver = {
                .owner  = THIS_MODULE,
                .name   = "lcs",
        },
+       .ccw_driver  = &lcs_ccw_driver,
        .setup       = lcs_probe_device,
        .remove      = lcs_remove_device,
        .set_online  = lcs_new_device,

diff --git a/drivers/s390/net/qeth_core_main.c b/drivers/s390/net/qeth_core_main.c
index bae7440..61cf3e9 100644 (file)
--- a/drivers/s390/net/qeth_core_main.c
+++ b/drivers/s390/net/qeth_core_main.c
@@ -5875,6 +5875,7 @@ static struct ccwgroup_driver qeth_core_ccwgroup_driver = {
                .owner = THIS_MODULE,
                .name = "qeth",
        },
+       .ccw_driver = &qeth_ccw_driver,
        .setup = qeth_core_probe_device,
        .remove = qeth_core_remove_device,
        .set_online = qeth_core_set_online,