From d69d804845985c29ab5be5a4b3b1f4787893daf8 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Mon, 1 Jul 2024 14:07:37 +0200 Subject: 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 Reviewed-by: Alex Elder Acked-by: Sumit Garg Link: https://lore.kernel.org/r/2024070136-wrongdoer-busily-01e8@gregkh Signed-off-by: Greg Kroah-Hartman --- drivers/dax/bus.c | 17 +++++++---------- 1 file changed, 7 insertions(+), 10 deletions(-) (limited to 'drivers/dax') diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c index 3ef9550bd2ca..fde29e0ad68b 100644 --- a/drivers/dax/bus.c +++ b/drivers/dax/bus.c @@ -39,12 +39,9 @@ static int dax_bus_uevent(const struct device *dev, struct kobj_uevent_env *env) return add_uevent_var(env, "MODALIAS=" DAX_DEVICE_MODALIAS_FMT, 0); } -static struct dax_device_driver *to_dax_drv(struct device_driver *drv) -{ - return container_of(drv, struct dax_device_driver, drv); -} +#define to_dax_drv(__drv) container_of_const(__drv, struct dax_device_driver, drv) -static struct dax_id *__dax_match_id(struct dax_device_driver *dax_drv, +static struct dax_id *__dax_match_id(const struct dax_device_driver *dax_drv, const char *dev_name) { struct dax_id *dax_id; @@ -57,7 +54,7 @@ static struct dax_id *__dax_match_id(struct dax_device_driver *dax_drv, return NULL; } -static int dax_match_id(struct dax_device_driver *dax_drv, struct device *dev) +static int dax_match_id(const struct dax_device_driver *dax_drv, struct device *dev) { int match; @@ -68,7 +65,7 @@ static int dax_match_id(struct dax_device_driver *dax_drv, struct device *dev) return match; } -static int dax_match_type(struct dax_device_driver *dax_drv, struct device *dev) +static int dax_match_type(const struct dax_device_driver *dax_drv, struct device *dev) { enum dax_driver_type type = DAXDRV_DEVICE_TYPE; struct dev_dax *dev_dax = to_dev_dax(dev); @@ -156,7 +153,7 @@ static struct attribute *dax_drv_attrs[] = { }; ATTRIBUTE_GROUPS(dax_drv); -static int dax_bus_match(struct device *dev, struct device_driver *drv); +static int dax_bus_match(struct device *dev, const struct device_driver *drv); /* * Static dax regions are regions created by an external subsystem @@ -250,9 +247,9 @@ static const struct bus_type dax_bus_type = { .drv_groups = dax_drv_groups, }; -static int dax_bus_match(struct device *dev, struct device_driver *drv) +static int dax_bus_match(struct device *dev, const struct device_driver *drv) { - struct dax_device_driver *dax_drv = to_dax_drv(drv); + const struct dax_device_driver *dax_drv = to_dax_drv(drv); if (dax_match_id(dax_drv, dev)) return 1; -- cgit v1.2.3