Commit f9b5e46f authored by Peter Collingbourne's avatar Peter Collingbourne Committed by Will Deacon
Browse files

kasan: split kasan_*enabled() functions into a separate header 

In an upcoming commit we are going to need to call
kasan_hw_tags_enabled() from arch/arm64/include/asm/mte.h. This
would create a circular dependency between headers if KASAN_GENERIC
or KASAN_SW_TAGS is enabled: linux/kasan.h -> linux/pgtable.h ->
asm/pgtable.h -> asm/mte.h -> linux/kasan.h. Break the cycle
by introducing a new header linux/kasan-enabled.h with the
kasan_*enabled() functions that can be included from asm/mte.h.

Link: https://linux-review.googlesource.com/id/I5b0d96c6ed0026fc790899e14d42b2fac6ab568e


Signed-off-by: default avatarPeter Collingbourne <pcc@google.com>
Reviewed-by: default avatarAndrey Konovalov <andreyknvl@gmail.com>
Link: https://lore.kernel.org/r/20220219012945.894950-1-pcc@google.com


Signed-off-by: default avatarWill Deacon <will@kernel.org>
parent dfd42fac

include/linux/kasan-enabled.h

0 → 100644
+33 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0 */

#ifndef _LINUX_KASAN_ENABLED_H

#define _LINUX_KASAN_ENABLED_H



#ifdef CONFIG_KASAN_HW_TAGS



DECLARE_STATIC_KEY_FALSE(kasan_flag_enabled);



static __always_inline bool kasan_enabled(void)

{

	return static_branch_likely(&kasan_flag_enabled);

}



static inline bool kasan_hw_tags_enabled(void)

{

	return kasan_enabled();

}



#else /* CONFIG_KASAN_HW_TAGS */



static inline bool kasan_enabled(void)

{

	return IS_ENABLED(CONFIG_KASAN);

}



static inline bool kasan_hw_tags_enabled(void)

{

	return false;

}



#endif /* CONFIG_KASAN_HW_TAGS */



#endif /* LINUX_KASAN_ENABLED_H */

include/linux/kasan.h

+1 −22
Original line number Diff line number Diff line
@@ -3,6 +3,7 @@ 
#define _LINUX_KASAN_H



#include <linux/bug.h>

#include <linux/kasan-enabled.h>

#include <linux/kernel.h>

#include <linux/static_key.h>

#include <linux/types.h>
@@ -83,33 +84,11 @@ static inline void kasan_disable_current(void) {} 


#ifdef CONFIG_KASAN_HW_TAGS



DECLARE_STATIC_KEY_FALSE(kasan_flag_enabled);



static __always_inline bool kasan_enabled(void)

{

	return static_branch_likely(&kasan_flag_enabled);

}



static inline bool kasan_hw_tags_enabled(void)

{

	return kasan_enabled();

}



void kasan_alloc_pages(struct page *page, unsigned int order, gfp_t flags);

void kasan_free_pages(struct page *page, unsigned int order);



#else /* CONFIG_KASAN_HW_TAGS */



static inline bool kasan_enabled(void)

{

	return IS_ENABLED(CONFIG_KASAN);

}



static inline bool kasan_hw_tags_enabled(void)

{

	return false;

}



static __always_inline void kasan_alloc_pages(struct page *page,

					      unsigned int order, gfp_t flags)

{