devres: provide devm_kstrdup_const()

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 <brgl@bgdev.pl>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Acked-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Acked-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 2 insertions, 0 deletions

diff --git a/include/linux/device.h b/include/linux/device.h
index c2022c1daef6..fecd9722400e 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -696,6 +696,8 @@ static inline void *devm_kcalloc(struct device *dev,
 }
 extern void devm_kfree(struct device *dev, const void *p);
 extern char *devm_kstrdup(struct device *dev, const char *s, gfp_t gfp) __malloc;
+extern const char *devm_kstrdup_const(struct device *dev,
+				      const char *s, gfp_t gfp);
 extern void *devm_kmemdup(struct device *dev, const void *src, size_t len,
 			  gfp_t gfp);