On Sun, Oct 14, 2018 at 05:20:09PM +0200, Bartosz Golaszewski wrote: > Provide a resource managed version of kstrdup_const(). This variant > internally calls devm_kstrdup() on pointers that are outside of > .rodata section and returns the string as is otherwise. > > Make devm_kfree() check if the passed pointer doesn't point to .rodata > and if so - don't actually destroy the resource. > > Signed-off-by: Bartosz Golaszewski <[email protected]> > Reviewed-by: Bjorn Andersson <[email protected]> > Acked-by: Mike Rapoport <[email protected]> > Acked-by: Rasmus Villemoes <[email protected]> > Reviewed-by: Geert Uytterhoeven <[email protected]> > Reviewed-by: Andy Shevchenko <[email protected]> > --- > drivers/base/devres.c | 31 +++++++++++++++++++++++++++++++ > include/linux/device.h | 2 ++ > 2 files changed, 33 insertions(+) > > diff --git a/drivers/base/devres.c b/drivers/base/devres.c > index 438c91a43508..00c70f0fcdcd 100644 > --- a/drivers/base/devres.c > +++ b/drivers/base/devres.c > @@ -11,6 +11,8 @@ > #include <linux/slab.h> > #include <linux/percpu.h> > > +#include <asm/sections.h> > + > #include "base.h" > > struct devres_node { > @@ -822,6 +824,28 @@ char *devm_kstrdup(struct device *dev, const char *s, > gfp_t gfp) > } > EXPORT_SYMBOL_GPL(devm_kstrdup); > > +/** > + * devm_kstrdup_const - resource managed conditional string duplication > + * @dev: device for which to duplicate the string > + * @s: the string to duplicate > + * @gfp: the GFP mask used in the kmalloc() call when allocating memory > + * > + * Strings allocated by devm_kstrdup_const will be automatically freed when > + * the associated device is detached. > + * > + * RETURNS: > + * Source string if it is in .rodata section otherwise it falls back to > + * devm_kstrdup. > + */ > +const char *devm_kstrdup_const(struct device *dev, const char *s, gfp_t gfp) > +{ > + if (is_kernel_rodata((unsigned long)s)) > + return s; > + > + return devm_kstrdup(dev, s, gfp); > +} > +EXPORT_SYMBOL(devm_kstrdup_const);
This should be EXPORT_SYMBOL_GPL() to match the rest of the file. I'll go fix that up when I apply it. thanks, greg k-h
