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/media/pci/bt8xx/bttv-gpio.c | 4 ++-- drivers/media/pci/bt8xx/bttv.h | 2 +- 2 files changed, 3 insertions(+), 3 deletions(-) (limited to 'drivers/media') diff --git a/drivers/media/pci/bt8xx/bttv-gpio.c b/drivers/media/pci/bt8xx/bttv-gpio.c index 6b7fea50328c..59a6f160aac7 100644 --- a/drivers/media/pci/bt8xx/bttv-gpio.c +++ b/drivers/media/pci/bt8xx/bttv-gpio.c @@ -28,9 +28,9 @@ /* ----------------------------------------------------------------------- */ /* internal: the bttv "bus" */ -static int bttv_sub_bus_match(struct device *dev, struct device_driver *drv) +static int bttv_sub_bus_match(struct device *dev, const struct device_driver *drv) { - struct bttv_sub_driver *sub = to_bttv_sub_drv(drv); + const struct bttv_sub_driver *sub = to_bttv_sub_drv(drv); int len = strlen(sub->wanted); if (0 == strncmp(dev_name(dev), sub->wanted, len)) diff --git a/drivers/media/pci/bt8xx/bttv.h b/drivers/media/pci/bt8xx/bttv.h index eed7eeb3b963..97bbed980f98 100644 --- a/drivers/media/pci/bt8xx/bttv.h +++ b/drivers/media/pci/bt8xx/bttv.h @@ -341,7 +341,7 @@ struct bttv_sub_driver { int (*probe)(struct bttv_sub_device *sub); void (*remove)(struct bttv_sub_device *sub); }; -#define to_bttv_sub_drv(x) container_of((x), struct bttv_sub_driver, drv) +#define to_bttv_sub_drv(x) container_of_const((x), struct bttv_sub_driver, drv) int bttv_sub_register(struct bttv_sub_driver *drv, char *wanted); int bttv_sub_unregister(struct bttv_sub_driver *drv); -- cgit v1.2.3-58-ga151