[PATCH mm v4 10/19] kasan: inline (un)poison_range and check_invalid_free

[Andrey Konovalov]

Using (un)poison_range() or check_invalid_free() currently results in
function calls. Move their definitions to mm/kasan/kasan.h and turn them
into static inline functions for hardware tag-based mode to avoid
unneeded function calls.

Signed-off-by: Andrey Konovalov <andreyknvl at google.com>
Reviewed-by: Marco Elver <elver at google.com>
Link: https://linux-review.googlesource.com/id/Ia9d8191024a12d1374675b3d27197f10193f50bb
---
 mm/kasan/hw_tags.c | 30 ------------------------------
 mm/kasan/kasan.h   | 45 ++++++++++++++++++++++++++++++++++++++++-----
 2 files changed, 40 insertions(+), 35 deletions(-)

diff --git a/mm/kasan/hw_tags.c b/mm/kasan/hw_tags.c
index 3cdd87d189f6..863fed4edd3f 100644
--- a/mm/kasan/hw_tags.c
+++ b/mm/kasan/hw_tags.c
@@ -10,7 +10,6 @@
 
 #include <linux/kasan.h>
 #include <linux/kernel.h>
-#include <linux/kfence.h>
 #include <linux/memory.h>
 #include <linux/mm.h>
 #include <linux/string.h>
@@ -31,35 +30,6 @@ void __init kasan_init_hw_tags(void)
 	pr_info("KernelAddressSanitizer initialized\n");
 }
 
-void poison_range(const void *address, size_t size, u8 value)
-{
-	/* Skip KFENCE memory if called explicitly outside of sl*b. */
-	if (is_kfence_address(address))
-		return;
-
-	hw_set_mem_tag_range(kasan_reset_tag(address),
-			round_up(size, KASAN_GRANULE_SIZE), value);
-}
-
-void unpoison_range(const void *address, size_t size)
-{
-	/* Skip KFENCE memory if called explicitly outside of sl*b. */
-	if (is_kfence_address(address))
-		return;
-
-	hw_set_mem_tag_range(kasan_reset_tag(address),
-			round_up(size, KASAN_GRANULE_SIZE), get_tag(address));
-}
-
-bool check_invalid_free(void *addr)
-{
-	u8 ptr_tag = get_tag(addr);
-	u8 mem_tag = hw_get_mem_tag(addr);
-
-	return (mem_tag == KASAN_TAG_INVALID) ||
-		(ptr_tag != KASAN_TAG_KERNEL && ptr_tag != mem_tag);
-}
-
 void kasan_set_free_info(struct kmem_cache *cache,
 				void *object, u8 tag)
 {
diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h
index 7876a2547b7d..8aa83b7ad79e 100644
--- a/mm/kasan/kasan.h
+++ b/mm/kasan/kasan.h
@@ -3,6 +3,7 @@
 #define __MM_KASAN_KASAN_H
 
 #include <linux/kasan.h>
+#include <linux/kfence.h>
 #include <linux/stackdepot.h>
 
 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
@@ -154,9 +155,6 @@ struct kasan_alloc_meta *kasan_get_alloc_meta(struct kmem_cache *cache,
 struct kasan_free_meta *kasan_get_free_meta(struct kmem_cache *cache,
 						const void *object);
 
-void poison_range(const void *address, size_t size, u8 value);
-void unpoison_range(const void *address, size_t size);
-
 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
 
 static inline const void *kasan_shadow_to_mem(const void *shadow_addr)
@@ -196,8 +194,6 @@ void print_tags(u8 addr_tag, const void *addr);
 static inline void print_tags(u8 addr_tag, const void *addr) { }
 #endif
 
-bool check_invalid_free(void *addr);
-
 void *find_first_bad_addr(void *addr, size_t size);
 const char *get_bug_type(struct kasan_access_info *info);
 void metadata_fetch_row(char *buffer, void *row);
@@ -278,6 +274,45 @@ static inline u8 random_tag(void) { return hw_get_random_tag(); }
 static inline u8 random_tag(void) { return 0; }
 #endif
 
+#ifdef CONFIG_KASAN_HW_TAGS
+
+static inline void poison_range(const void *address, size_t size, u8 value)
+{
+	/* Skip KFENCE memory if called explicitly outside of sl*b. */
+	if (is_kfence_address(address))
+		return;
+
+	hw_set_mem_tag_range(kasan_reset_tag(address),
+			round_up(size, KASAN_GRANULE_SIZE), value);
+}
+
+static inline void unpoison_range(const void *address, size_t size)
+{
+	/* Skip KFENCE memory if called explicitly outside of sl*b. */
+	if (is_kfence_address(address))
+		return;
+
+	hw_set_mem_tag_range(kasan_reset_tag(address),
+			round_up(size, KASAN_GRANULE_SIZE), get_tag(address));
+}
+
+static inline bool check_invalid_free(void *addr)
+{
+	u8 ptr_tag = get_tag(addr);
+	u8 mem_tag = hw_get_mem_tag(addr);
+
+	return (mem_tag == KASAN_TAG_INVALID) ||
+		(ptr_tag != KASAN_TAG_KERNEL && ptr_tag != mem_tag);
+}
+
+#else /* CONFIG_KASAN_HW_TAGS */
+
+void poison_range(const void *address, size_t size, u8 value);
+void unpoison_range(const void *address, size_t size);
+bool check_invalid_free(void *addr);
+
+#endif /* CONFIG_KASAN_HW_TAGS */
+
 /*
  * Exported functions for interfaces called from assembly or from generated
  * code. Declarations here to avoid warning about missing declarations.
-- 
2.29.2.454.gaff20da3a2-goog