driver core: have match() callback in struct bus_type take a const *

In the match() callback, the struct device_driver * should not be
changed, so change the function callback to be a const *.  This is one
step of many towards making the driver core safe to have struct
device_driver in read-only memory.

Because the match() callback is in all busses, all busses are modified
to handle this properly.  This does entail switching some container_of()
calls to container_of_const() to properly handle the constant *.

For some busses, like PCI and USB and HV, the const * is cast away in
the match callback as those busses do want to modify those structures at
this point in time (they have a local lock in the driver structure.)
That will have to be changed in the future if they wish to have their
struct device * in read-only-memory.

Cc: Rafael J. Wysocki <rafael@kernel.org>
Reviewed-by: Alex Elder <elder@kernel.org>
Acked-by: Sumit Garg <sumit.garg@linaro.org>
Link: https://lore.kernel.org/r/2024070136-wrongdoer-busily-01e8@gregkh
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

6 files changed, 10 insertions, 10 deletions

diff --git a/drivers/input/gameport/gameport.c b/drivers/input/gameport/gameport.c
index cfcc81c47b50..e77dd0740d27 100644
--- a/drivers/input/gameport/gameport.c
+++ b/drivers/input/gameport/gameport.c
@@ -806,9 +806,9 @@ start_over:
 }
 EXPORT_SYMBOL(gameport_unregister_driver);
 
-static int gameport_bus_match(struct device *dev, struct device_driver *drv)
+static int gameport_bus_match(struct device *dev, const struct device_driver *drv)
 {
-	struct gameport_driver *gameport_drv = to_gameport_driver(drv);
+	const struct gameport_driver *gameport_drv = to_gameport_driver(drv);
 
 	return !gameport_drv->ignore;
 }
diff --git a/drivers/input/rmi4/rmi_bus.c b/drivers/input/rmi4/rmi_bus.c
index 343030290d78..3aee04837205 100644
--- a/drivers/input/rmi4/rmi_bus.c
+++ b/drivers/input/rmi4/rmi_bus.c
@@ -144,9 +144,9 @@ bool rmi_is_function_device(struct device *dev)
 	return dev->type == &rmi_function_type;
 }
 
-static int rmi_function_match(struct device *dev, struct device_driver *drv)
+static int rmi_function_match(struct device *dev, const struct device_driver *drv)
 {
-	struct rmi_function_handler *handler = to_rmi_function_handler(drv);
+	const struct rmi_function_handler *handler = to_rmi_function_handler(drv);
 	struct rmi_function *fn = to_rmi_function(dev);
 
 	return fn->fd.function_number == handler->func;
@@ -333,7 +333,7 @@ EXPORT_SYMBOL_GPL(rmi_unregister_function_handler);
 
 /* Bus specific stuff */
 
-static int rmi_bus_match(struct device *dev, struct device_driver *drv)
+static int rmi_bus_match(struct device *dev, const struct device_driver *drv)
 {
 	bool physical = rmi_is_physical_device(dev);
 
diff --git a/drivers/input/rmi4/rmi_bus.h b/drivers/input/rmi4/rmi_bus.h
index ea46ad9447ec..d4d0d82c69aa 100644
--- a/drivers/input/rmi4/rmi_bus.h
+++ b/drivers/input/rmi4/rmi_bus.h
@@ -87,7 +87,7 @@ struct rmi_function_handler {
 };
 
 #define to_rmi_function_handler(d) \
-		container_of(d, struct rmi_function_handler, driver)
+		container_of_const(d, struct rmi_function_handler, driver)
 
 int __must_check __rmi_register_function_handler(struct rmi_function_handler *,
 						 struct module *, const char *);
diff --git a/drivers/input/rmi4/rmi_driver.c b/drivers/input/rmi4/rmi_driver.c
index ef9ea295f9e0..2168b6cd7167 100644
--- a/drivers/input/rmi4/rmi_driver.c
+++ b/drivers/input/rmi4/rmi_driver.c
@@ -1258,7 +1258,7 @@ static struct rmi_driver rmi_physical_driver = {
 	.set_input_params = rmi_driver_set_input_params,
 };
 
-bool rmi_is_physical_driver(struct device_driver *drv)
+bool rmi_is_physical_driver(const struct device_driver *drv)
 {
 	return drv == &rmi_physical_driver.driver;
 }
diff --git a/drivers/input/rmi4/rmi_driver.h b/drivers/input/rmi4/rmi_driver.h
index 1c6c6086c0e5..3bfe9013043e 100644
--- a/drivers/input/rmi4/rmi_driver.h
+++ b/drivers/input/rmi4/rmi_driver.h
@@ -84,7 +84,7 @@ int rmi_register_desc_calc_reg_offset(
 bool rmi_register_desc_has_subpacket(const struct rmi_register_desc_item *item,
 			u8 subpacket);
 
-bool rmi_is_physical_driver(struct device_driver *);
+bool rmi_is_physical_driver(const struct device_driver *);
 int rmi_register_physical_driver(void);
 void rmi_unregister_physical_driver(void);
 void rmi_free_function_list(struct rmi_device *rmi_dev);
diff --git a/drivers/input/serio/serio.c b/drivers/input/serio/serio.c
index a8838b522627..36bf2c50d8e9 100644
--- a/drivers/input/serio/serio.c
+++ b/drivers/input/serio/serio.c
@@ -877,10 +877,10 @@ static void serio_set_drv(struct serio *serio, struct serio_driver *drv)
 	serio_continue_rx(serio);
 }
 
-static int serio_bus_match(struct device *dev, struct device_driver *drv)
+static int serio_bus_match(struct device *dev, const struct device_driver *drv)
 {
 	struct serio *serio = to_serio_port(dev);
-	struct serio_driver *serio_drv = to_serio_driver(drv);
+	const struct serio_driver *serio_drv = to_serio_driver(drv);
 
 	if (serio->manual_bind || serio_drv->manual_bind)
 		return 0;