mm/kasan: Convert to struct folio and struct slab

KASAN accesses some slab related struct page fields so we need to
convert it to struct slab. Some places are a bit simplified thanks to
kasan_addr_to_slab() encapsulating the PageSlab flag check through
virt_to_slab().  When resolving object address to either a real slab or
a large kmalloc, use struct folio as the intermediate type for testing
the slab flag to avoid unnecessary implicit compound_head().

[ vbabka@suse.cz: use struct folio, adjust to differences in previous
  patches ]

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Reviewed-by: Roman Gushchin <guro@fb.com>
Tested-by: Hyeongogn Yoo <42.hyeyoo@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: <kasan-dev@googlegroups.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h
index aebd8df86a1f..c17fa8d26ffe 100644
--- a/mm/kasan/kasan.h
+++ b/mm/kasan/kasan.h
@@ -265,6 +265,7 @@ bool kasan_report(unsigned long addr, size_t size,
 void kasan_report_invalid_free(void *object, unsigned long ip);
 
 struct page *kasan_addr_to_page(const void *addr);
+struct slab *kasan_addr_to_slab(const void *addr);
 
 depot_stack_handle_t kasan_save_stack(gfp_t flags, bool can_alloc);
 void kasan_set_track(struct kasan_track *track, gfp_t flags);