[PATCH v2 3/5] mm/sl[auo]b: move definition of __ksize() to mm/slab.h

From: Hyeonggon Yoo
Date: Fri Mar 04 2022 - 01:35:49 EST


__ksize() is only called by KASAN. Remove export symbol and move
definition to mm/slab.h as we don't want to grow its callers.

[ willy@xxxxxxxxxxxxx: Move definition to mm/slab.h and reduce comments ]

Signed-off-by: Hyeonggon Yoo <42.hyeyoo@xxxxxxxxx>
---
include/linux/slab.h | 1 -
mm/slab.h | 2 ++
mm/slab_common.c | 9 +--------
mm/slob.c | 1 -
4 files changed, 3 insertions(+), 10 deletions(-)

diff --git a/include/linux/slab.h b/include/linux/slab.h
index e7b3330db4f3..d2b896553315 100644
--- a/include/linux/slab.h
+++ b/include/linux/slab.h
@@ -182,7 +182,6 @@ int kmem_cache_shrink(struct kmem_cache *s);
void * __must_check krealloc(const void *objp, size_t new_size, gfp_t flags) __alloc_size(2);
void kfree(const void *objp);
void kfree_sensitive(const void *objp);
-size_t __ksize(const void *objp);
size_t ksize(const void *objp);
#ifdef CONFIG_PRINTK
bool kmem_valid_obj(void *object);
diff --git a/mm/slab.h b/mm/slab.h
index 31e98beb47a3..79b319d58504 100644
--- a/mm/slab.h
+++ b/mm/slab.h
@@ -685,6 +685,8 @@ static inline void free_large_kmalloc(struct folio *folio, void *object)
}
#endif /* CONFIG_SLOB */

+size_t __ksize(const void *objp);
+
static inline size_t slab_ksize(const struct kmem_cache *s)
{
#ifndef CONFIG_SLUB
diff --git a/mm/slab_common.c b/mm/slab_common.c
index 1d2f92e871d2..b126fc7247b9 100644
--- a/mm/slab_common.c
+++ b/mm/slab_common.c
@@ -1247,13 +1247,7 @@ EXPORT_SYMBOL(kfree_sensitive);

#ifndef CONFIG_SLOB
/**
- * __ksize -- Uninstrumented ksize.
- * @objp: pointer to the object
- *
- * Unlike ksize(), __ksize() is uninstrumented, and does not provide the same
- * safety checks as ksize() with KASAN instrumentation enabled.
- *
- * Return: size of the actual memory used by @objp in bytes
+ * __ksize -- Uninstrumented ksize. Only called by KASAN.
*/
size_t __ksize(const void *object)
{
@@ -1269,7 +1263,6 @@ size_t __ksize(const void *object)

return slab_ksize(folio_slab(folio)->slab_cache);
}
-EXPORT_SYMBOL(__ksize);
#endif

/**
diff --git a/mm/slob.c b/mm/slob.c
index 60c5842215f1..d8af6c54f133 100644
--- a/mm/slob.c
+++ b/mm/slob.c
@@ -588,7 +588,6 @@ size_t __ksize(const void *block)
m = (unsigned int *)(block - align);
return SLOB_UNITS(*m) * SLOB_UNIT;
}
-EXPORT_SYMBOL(__ksize);

int __kmem_cache_create(struct kmem_cache *c, slab_flags_t flags)
{
--
2.33.1