kernel/drivers/base/base.h, branch linux-6.9.y

module: don't ignore sysfs_create_link() failures

2024-06-12T09:39:09Z

[ Upstream commit 85d2b0aa170351380be39fe4ff7973df1427fe76 ] The sysfs_create_link() return code is marked as __must_check, but the module_add_driver() function tries hard to not care, by assigning the return code to a variable. When building with 'make W=1', gcc still warns because this variable is only assigned but not used: drivers/base/module.c: In function 'module_add_driver': drivers/base/module.c:36:6: warning: variable 'no_warn' set but not used [-Wunused-but-set-variable] Rework the code to properly unwind and return the error code to the caller. My reading of the original code was that it tries to not fail when the links already exist, so keep ignoring -EEXIST errors. Fixes: e17e0f51aeea ("Driver core: show drivers in /sys/module/") See-also: 4a7fb6363f2d ("add __must_check to device management code") Signed-off-by: Arnd Bergmann Reviewed-by: Luis Chamberlain Link: https://lore.kernel.org/r/20240408080616.3911573-1-arnd@kernel.org Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

block: make block_class constant

2024-03-06T15:29:20Z

Since commit 43a7206b0963 ("driver core: class: make class_register() take a const *"), the driver core allows for struct class to be in read-only memory, so move the block_class structure to be declared at build time placing it into read-only memory, instead of having to be dynamically allocated at boot time. Cc: Greg Kroah-Hartman Suggested-by: Greg Kroah-Hartman Signed-off-by: Ricardo B. Marliere Reviewed-by: Christoph Hellwig Link: https://lore.kernel.org/r/20240305-class_cleanup-block-v1-1-130bb27b9c72@marliere.net Signed-off-by: Jens Axboe

driver core: class: make class_register() take a const *

2023-04-03T19:42:46Z

Now that the class code is cleaned up to not modify the class pointer registered with it, change class_register() to take a const * to allow the structure to be placed into read-only memory. Acked-by: Rafael J. Wysocki Link: https://lore.kernel.org/r/2023040248-customary-release-4aec@gregkh Signed-off-by: Greg Kroah-Hartman

driver core: make sysfs_dev_char_kobj static

2023-03-31T15:45:18Z

Nothing outside of drivers/base/core.c uses sysfs_dev_char_kobj, so make it static and document what it is used for so we remember it the next time we touch it 15 years from now. Acked-by: Rafael J. Wysocki Link: https://lore.kernel.org/r/20230331093318.82288-7-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman

driver core: clean up the logic to determine which /sys/dev/ directory to use

2023-03-31T15:45:07Z

When a dev_t is set in a struct device, an symlink in /sys/dev/ is created for it either under /sys/dev/block/ or /sys/dev/char/ depending on the device type. The logic to determine this would trigger off of the class of the object, and the kobj_type set in that location. But it turns out that this deep nesting isn't needed at all, as it's either a choice of block or "everything else" which is a char device. So make the logic a lot more simple and obvious, and remove the incorrect comments in the code that tried to document something that was not happening at all (it is impossible to set class->dev_kobj to NULL as the class core prevented that from happening. This removes the only place that class->dev_kobj was being used, so after this, it can be removed entirely. Acked-by: Rafael J. Wysocki Link: https://lore.kernel.org/r/20230331093318.82288-4-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman

driver core: core: move to use class_to_subsys()

2023-03-31T13:13:35Z

There are a number of places in core.c that need access to the private subsystem structure of struct class, so move them to use class_to_subsys() instead of accessing it directly. This requires exporting class_to_subsys() out of class.c, but keeping it local to the driver core. Reviewed-by: Rafael J. Wysocki Link: https://lore.kernel.org/r/20230331093318.82288-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman

driver core: move sysfs_dev_char_kobj out of class.h

2023-03-27T16:24:29Z

The structure sysfs_dev_char_kobj is local only to the driver core code, so move it out of the global class.h file and into the internal base.h file as no one else should be touching this symbol. Acked-by: Rafael J. Wysocki Link: https://lore.kernel.org/r/20230327160319.513974-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman

driver core: bus: move documentation for lock_key to proper location.

2023-03-25T08:38:08Z

In commit 37e98d9bedb5 ("driver core: bus: move lock_class_key into dynamic structure"), the lock_key variable moved out of struct bus_type and into struct subsys_private, yet the documentation for it did not move. Fix that up and place the documentation comment in the correct location. Cc: "Rafael J. Wysocki" Fixes: 37e98d9bedb5 ("driver core: bus: move lock_class_key into dynamic structure") Link: https://lore.kernel.org/r/20230324090814.386654-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman

driver core: base.h: remove extern from function prototypes

2023-03-24T14:35:45Z

The kernel coding style does not require 'extern' in function prototypes in .h files, so remove them from drivers/base/base.h as they are not needed. Acked-by: Rafael J. Wysocki Link: https://lore.kernel.org/r/20230324122711.2664537-4-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman

driver core: bus: constantify bus_register()

2023-03-23T12:21:17Z

bus_register() is now safe to take a constant * to bus_type, so make that change and mark the subsys_private bus_type * constant as well. Cc: "Rafael J. Wysocki" Link: https://lore.kernel.org/r/20230313182918.1312597-24-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman