Since commit ee6d3dd4ed ("driver core: make kobj_type constant.")
the driver core allows the usage of const struct kobj_type.
Take advantage of this to constify the structure definition to prevent
modification at runtime.
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
strtobool() is the same as kstrtobool().
However, the latter is more used within the kernel.
In order to remove strtobool() and slightly simplify kstrtox.h, switch to
the other function name.
While at it, include the corresponding header file (<linux/kstrtox.h>)
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Pull driver core updates from Greg KH:
"Here is the set of driver core and kernfs changes for 6.2-rc1.
The "big" change in here is the addition of a new macro,
container_of_const() that will preserve the "const-ness" of a pointer
passed into it.
The "problem" of the current container_of() macro is that if you pass
in a "const *", out of it can comes a non-const pointer unless you
specifically ask for it. For many usages, we want to preserve the
"const" attribute by using the same call. For a specific example, this
series changes the kobj_to_dev() macro to use it, allowing it to be
used no matter what the const value is. This prevents every subsystem
from having to declare 2 different individual macros (i.e.
kobj_const_to_dev() and kobj_to_dev()) and having the compiler enforce
the const value at build time, which having 2 macros would not do
either.
The driver for all of this have been discussions with the Rust kernel
developers as to how to properly mark driver core, and kobject,
objects as being "non-mutable". The changes to the kobject and driver
core in this pull request are the result of that, as there are lots of
paths where kobjects and device pointers are not modified at all, so
marking them as "const" allows the compiler to enforce this.
So, a nice side affect of the Rust development effort has been already
to clean up the driver core code to be more obvious about object
rules.
All of this has been bike-shedded in quite a lot of detail on lkml
with different names and implementations resulting in the tiny version
we have in here, much better than my original proposal. Lots of
subsystem maintainers have acked the changes as well.
Other than this change, included in here are smaller stuff like:
- kernfs fixes and updates to handle lock contention better
- vmlinux.lds.h fixes and updates
- sysfs and debugfs documentation updates
- device property updates
All of these have been in the linux-next tree for quite a while with
no problems"
* tag 'driver-core-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (58 commits)
device property: Fix documentation for fwnode_get_next_parent()
firmware_loader: fix up to_fw_sysfs() to preserve const
usb.h: take advantage of container_of_const()
device.h: move kobj_to_dev() to use container_of_const()
container_of: add container_of_const() that preserves const-ness of the pointer
driver core: fix up missed drivers/s390/char/hmcdrv_dev.c class.devnode() conversion.
driver core: fix up missed scsi/cxlflash class.devnode() conversion.
driver core: fix up some missing class.devnode() conversions.
driver core: make struct class.devnode() take a const *
driver core: make struct class.dev_uevent() take a const *
cacheinfo: Remove of_node_put() for fw_token
device property: Add a blank line in Kconfig of tests
device property: Rename goto label to be more precise
device property: Move PROPERTY_ENTRY_BOOL() a bit down
device property: Get rid of __PROPERTY_ENTRY_ARRAY_EL*SIZE*()
kernfs: fix all kernel-doc warnings and multiple typos
driver core: pass a const * into of_device_uevent()
kobject: kset_uevent_ops: make name() callback take a const *
kobject: kset_uevent_ops: make filter() callback take a const *
kobject: make kobject_namespace take a const *
...
param_sysfs_init(), and in particular param_sysfs_builtin() is rather
time-consuming; for my board, it currently takes about 30ms.
That amounts to about 3% of the time budget I have from U-Boot hands
over control to linux and linux must assume responsibility for keeping
the external watchdog happy.
We must still continue to initialize module_kset at subsys_initcall
time, since otherwise any request_module() would fail in
mod_sysfs_init(). However, the bulk of the work in
param_sysfs_builtin(), namely populating /sys/module/*/version and/or
/sys/module/*/parameters/ for builtin modules, can be deferred to
late_initcall time - there's no userspace yet anyway to observe
contents of /sys or the lack thereof.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
The variable module_sysfs_initialized is used for checking whether
module_kset has been initialized. Checking module_kset itself works
just fine for that.
This is a leftover from commit 7405c1e15e ("kset: convert /sys/module
to use kset_create").
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
[mcgrof: adjusted commit log as suggested by Christophe Leroy]
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
It is a useful helper hence move it to common code so others can enjoy
it.
Suggested-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Pull modules updates from Jessica Yu:
"Summary of modules changes for the 5.11 merge window:
- Fix a race condition between systemd/udev and the module loader.
The module loader was sending a uevent before the module was fully
initialized (i.e., before its init function has been called). This
means udev can start processing the module uevent before the module
has finished initializing, and some udev rules expect that the
module has initialized already upon receiving the uevent.
This resulted in some systemd mount units failing if udev processes
the event faster than the module can finish init. This is fixed by
delaying the uevent until after the module has called its init
routine.
- Make the linker array sections for kernel params and module version
attributes more robust by switching to use the alignment of the
type in question.
Namely, linker section arrays will be constructed using the
alignment required by the struct (using __alignof__()) as opposed
to a specific value such as sizeof(void *) or sizeof(long). This is
less likely to cause breakages should the size of the type ever
change (Johan Hovold)
- Fix module state inconsistency by setting it back to GOING when a
module fails to load and is on its way out (Miroslav Benes)
- Some comment and code cleanups (Sergey Shtylyov)"
* tag 'modules-for-v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
module: delay kobject uevent until after module init call
module: drop semicolon from version macro
init: use type alignment for kernel parameters
params: clean up module-param macros
params: use type alignment for kernel parameters
params: drop redundant "unused" attributes
module: simplify version-attribute handling
module: drop version-attribute alignment
module: fix comment style
module: add more 'kernel-doc' comments
module: fix up 'kernel-doc' comments
module: only handle errors with the *switch* statement in module_sig_check()
module: avoid *goto*s in module_sig_check()
module: merge repetitive strings in module_sig_check()
module: set MODULE_STATE_GOING state when a module fails to load
Instead of using the array-of-pointers trick to avoid having gcc mess up
the built-in module-version array stride, specify type alignment when
declaring entries to prevent gcc from increasing alignment.
This is essentially an alternative (one-line) fix to the problem
addressed by commit b4bc842802 ("module: deal with alignment issues in
built-in module versions").
gcc can increase the alignment of larger objects with static extent as
an optimisation, but this can be suppressed by using the aligned
attribute when declaring variables.
Note that we have been relying on this behaviour for kernel parameters
for 16 years and it indeed hasn't changed since the introduction of the
aligned attribute in gcc-3.1.
Link: https://lore.kernel.org/lkml/20201103175711.10731-1-johan@kernel.org
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
