path: root/include
diff options
authorRussell King <rmk+kernel@arm.linux.org.uk>2015-09-24 20:36:02 +0100
committerDavid S. Miller <davem@davemloft.net>2015-09-24 23:04:52 -0700
commit3e3aaf649416988ca8be4ad2c52dc24d8be7b46e (patch)
tree94f37082bd659379c74f9627c7be48c5147ec2fe /include
parente496ae690b2faff751e1849fb97b060615e21f28 (diff)
phy: fix mdiobus module safety
Re-implement the mdiobus module refcounting to ensure that we actually ensure that the mdiobus module code does not go away while we might call into it. The old scheme using bus->dev.driver was buggy, because bus->dev is a class device which never has a struct device_driver associated with it, and hence the associated code trying to obtain a refcount did nothing useful. Instead, take the approach that other subsystems do: pass the module when calling mdiobus_register(), and record that in the mii_bus struct. When we need to increment the module use count in the phy code, use this stored pointer. When the phy is deteched, drop the module refcount, remembering that the phy device might go away at that point. This doesn't stop the mii_bus going away while there are in-use phys - it merely stops the underlying code vanishing. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include')
1 files changed, 4 insertions, 1 deletions
diff --git a/include/linux/phy.h b/include/linux/phy.h
index 962387a192f1..11bce44f6d65 100644
--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -19,6 +19,7 @@
#include <linux/spinlock.h>
#include <linux/ethtool.h>
#include <linux/mii.h>
+#include <linux/module.h>
#include <linux/timer.h>
#include <linux/workqueue.h>
#include <linux/mod_devicetable.h>
@@ -153,6 +154,7 @@ struct sk_buff;
* PHYs should register using this structure
struct mii_bus {
+ struct module *owner;
const char *name;
char id[MII_BUS_ID_SIZE];
void *priv;
@@ -198,7 +200,8 @@ static inline struct mii_bus *mdiobus_alloc(void)
return mdiobus_alloc_size(0);
-int mdiobus_register(struct mii_bus *bus);
+int __mdiobus_register(struct mii_bus *bus, struct module *owner);
+#define mdiobus_register(bus) __mdiobus_register(bus, THIS_MODULE)
void mdiobus_unregister(struct mii_bus *bus);
void mdiobus_free(struct mii_bus *bus);
struct mii_bus *devm_mdiobus_alloc_size(struct device *dev, int sizeof_priv);

Privacy Policy