[PATCH V2] LoongArch: Don't inline kasan_mem_to_shadow()/kasan_shadow_to_mem()

From: Huacai Chen
Date: Mon Sep 11 2023 - 23:28:40 EST


As Linus suggested, kasan_mem_to_shadow()/kasan_shadow_to_mem() are not
performance-critical and too big to inline. This is simply wrong so just
define them out-of-line.

If they really need to be inlined in future, such as the objtool / SMAP
issue for X86, we should mark them __always_inline.

Suggested-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Huacai Chen <chenhuacai@xxxxxxxxxxx>
---
arch/loongarch/include/asm/kasan.h | 59 +++---------------------------
arch/loongarch/mm/kasan_init.c | 51 ++++++++++++++++++++++++++
2 files changed, 57 insertions(+), 53 deletions(-)

diff --git a/arch/loongarch/include/asm/kasan.h b/arch/loongarch/include/asm/kasan.h
index a12ecab37da7..cd6084f4e153 100644
--- a/arch/loongarch/include/asm/kasan.h
+++ b/arch/loongarch/include/asm/kasan.h
@@ -60,63 +60,16 @@
extern bool kasan_early_stage;
extern unsigned char kasan_early_shadow_page[PAGE_SIZE];

-#define kasan_arch_is_ready kasan_arch_is_ready
-static __always_inline bool kasan_arch_is_ready(void)
-{
- return !kasan_early_stage;
-}
-
#define kasan_mem_to_shadow kasan_mem_to_shadow
-static inline void *kasan_mem_to_shadow(const void *addr)
-{
- if (!kasan_arch_is_ready()) {
- return (void *)(kasan_early_shadow_page);
- } else {
- unsigned long maddr = (unsigned long)addr;
- unsigned long xrange = (maddr >> XRANGE_SHIFT) & 0xffff;
- unsigned long offset = 0;
-
- maddr &= XRANGE_SHADOW_MASK;
- switch (xrange) {
- case XKPRANGE_CC_SEG:
- offset = XKPRANGE_CC_SHADOW_OFFSET;
- break;
- case XKPRANGE_UC_SEG:
- offset = XKPRANGE_UC_SHADOW_OFFSET;
- break;
- case XKVRANGE_VC_SEG:
- offset = XKVRANGE_VC_SHADOW_OFFSET;
- break;
- default:
- WARN_ON(1);
- return NULL;
- }
-
- return (void *)((maddr >> KASAN_SHADOW_SCALE_SHIFT) + offset);
- }
-}
+void *kasan_mem_to_shadow(const void *addr);

#define kasan_shadow_to_mem kasan_shadow_to_mem
-static inline const void *kasan_shadow_to_mem(const void *shadow_addr)
+const void *kasan_shadow_to_mem(const void *shadow_addr);
+
+#define kasan_arch_is_ready kasan_arch_is_ready
+static __always_inline bool kasan_arch_is_ready(void)
{
- unsigned long addr = (unsigned long)shadow_addr;
-
- if (unlikely(addr > KASAN_SHADOW_END) ||
- unlikely(addr < KASAN_SHADOW_START)) {
- WARN_ON(1);
- return NULL;
- }
-
- if (addr >= XKVRANGE_VC_SHADOW_OFFSET)
- return (void *)(((addr - XKVRANGE_VC_SHADOW_OFFSET) << KASAN_SHADOW_SCALE_SHIFT) + XKVRANGE_VC_START);
- else if (addr >= XKPRANGE_UC_SHADOW_OFFSET)
- return (void *)(((addr - XKPRANGE_UC_SHADOW_OFFSET) << KASAN_SHADOW_SCALE_SHIFT) + XKPRANGE_UC_START);
- else if (addr >= XKPRANGE_CC_SHADOW_OFFSET)
- return (void *)(((addr - XKPRANGE_CC_SHADOW_OFFSET) << KASAN_SHADOW_SCALE_SHIFT) + XKPRANGE_CC_START);
- else {
- WARN_ON(1);
- return NULL;
- }
+ return !kasan_early_stage;
}

#define addr_has_metadata addr_has_metadata
diff --git a/arch/loongarch/mm/kasan_init.c b/arch/loongarch/mm/kasan_init.c
index da68bc1a4643..cc3e81fe0186 100644
--- a/arch/loongarch/mm/kasan_init.c
+++ b/arch/loongarch/mm/kasan_init.c
@@ -35,6 +35,57 @@ static pgd_t kasan_pg_dir[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE);

bool kasan_early_stage = true;

+void *kasan_mem_to_shadow(const void *addr)
+{
+ if (!kasan_arch_is_ready()) {
+ return (void *)(kasan_early_shadow_page);
+ } else {
+ unsigned long maddr = (unsigned long)addr;
+ unsigned long xrange = (maddr >> XRANGE_SHIFT) & 0xffff;
+ unsigned long offset = 0;
+
+ maddr &= XRANGE_SHADOW_MASK;
+ switch (xrange) {
+ case XKPRANGE_CC_SEG:
+ offset = XKPRANGE_CC_SHADOW_OFFSET;
+ break;
+ case XKPRANGE_UC_SEG:
+ offset = XKPRANGE_UC_SHADOW_OFFSET;
+ break;
+ case XKVRANGE_VC_SEG:
+ offset = XKVRANGE_VC_SHADOW_OFFSET;
+ break;
+ default:
+ WARN_ON(1);
+ return NULL;
+ }
+
+ return (void *)((maddr >> KASAN_SHADOW_SCALE_SHIFT) + offset);
+ }
+}
+
+const void *kasan_shadow_to_mem(const void *shadow_addr)
+{
+ unsigned long addr = (unsigned long)shadow_addr;
+
+ if (unlikely(addr > KASAN_SHADOW_END) ||
+ unlikely(addr < KASAN_SHADOW_START)) {
+ WARN_ON(1);
+ return NULL;
+ }
+
+ if (addr >= XKVRANGE_VC_SHADOW_OFFSET)
+ return (void *)(((addr - XKVRANGE_VC_SHADOW_OFFSET) << KASAN_SHADOW_SCALE_SHIFT) + XKVRANGE_VC_START);
+ else if (addr >= XKPRANGE_UC_SHADOW_OFFSET)
+ return (void *)(((addr - XKPRANGE_UC_SHADOW_OFFSET) << KASAN_SHADOW_SCALE_SHIFT) + XKPRANGE_UC_START);
+ else if (addr >= XKPRANGE_CC_SHADOW_OFFSET)
+ return (void *)(((addr - XKPRANGE_CC_SHADOW_OFFSET) << KASAN_SHADOW_SCALE_SHIFT) + XKPRANGE_CC_START);
+ else {
+ WARN_ON(1);
+ return NULL;
+ }
+}
+
/*
* Alloc memory for shadow memory page table.
*/
--
2.39.3