slab, slub, slob: add slab_flags_t

Add sparse-checked slab_flags_t for struct kmem_cache::flags (SLAB_POISON,
etc).

SLAB is bloated temporarily by switching to "unsigned long", but only
temporarily.

Link: http://lkml.kernel.org/r/20171021100225.GA22428@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Pekka Enberg <penberg@kernel.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

6 files changed, 46 insertions, 31 deletions

diff --git a/include/linux/kasan.h b/include/linux/kasan.h
index 5017269e3f04..e3eb834c9a35 100644
--- a/include/linux/kasan.h
+++ b/include/linux/kasan.h
@@ -46,7 +46,7 @@ void kasan_alloc_pages(struct page *page, unsigned int order);
 void kasan_free_pages(struct page *page, unsigned int order);
 
 void kasan_cache_create(struct kmem_cache *cache, size_t *size,
-			unsigned long *flags);
+			slab_flags_t *flags);
 void kasan_cache_shrink(struct kmem_cache *cache);
 void kasan_cache_shutdown(struct kmem_cache *cache);
 
@@ -95,7 +95,7 @@ static inline void kasan_free_pages(struct page *page, unsigned int order) {}
 
 static inline void kasan_cache_create(struct kmem_cache *cache,
 				      size_t *size,
-				      unsigned long *flags) {}
+				      slab_flags_t *flags) {}
 static inline void kasan_cache_shrink(struct kmem_cache *cache) {}
 static inline void kasan_cache_shutdown(struct kmem_cache *cache) {}
 
diff --git a/include/linux/kmemleak.h b/include/linux/kmemleak.h
index 590343f6c1b1..5ac416e2d339 100644
--- a/include/linux/kmemleak.h
+++ b/include/linux/kmemleak.h
@@ -48,14 +48,14 @@ extern void kmemleak_not_leak_phys(phys_addr_t phys) __ref;
 extern void kmemleak_ignore_phys(phys_addr_t phys) __ref;
 
 static inline void kmemleak_alloc_recursive(const void *ptr, size_t size,
-					    int min_count, unsigned long flags,
+					    int min_count, slab_flags_t flags,
 					    gfp_t gfp)
 {
 	if (!(flags & SLAB_NOLEAKTRACE))
 		kmemleak_alloc(ptr, size, min_count, gfp);
 }
 
-static inline void kmemleak_free_recursive(const void *ptr, unsigned long flags)
+static inline void kmemleak_free_recursive(const void *ptr, slab_flags_t flags)
 {
 	if (!(flags & SLAB_NOLEAKTRACE))
 		kmemleak_free(ptr);
@@ -76,7 +76,7 @@ static inline void kmemleak_alloc(const void *ptr, size_t size, int min_count,
 {
 }
 static inline void kmemleak_alloc_recursive(const void *ptr, size_t size,
-					    int min_count, unsigned long flags,
+					    int min_count, slab_flags_t flags,
 					    gfp_t gfp)
 {
 }
@@ -94,7 +94,7 @@ static inline void kmemleak_free(const void *ptr)
 static inline void kmemleak_free_part(const void *ptr, size_t size)
 {
 }
-static inline void kmemleak_free_recursive(const void *ptr, unsigned long flags)
+static inline void kmemleak_free_recursive(const void *ptr, slab_flags_t flags)
 {
 }
 static inline void kmemleak_free_percpu(const void __percpu *ptr)
diff --git a/include/linux/slab.h b/include/linux/slab.h
index af5aa65c7c18..0c4c579f52ed 100644
--- a/include/linux/slab.h
+++ b/include/linux/slab.h
@@ -21,13 +21,20 @@
  * Flags to pass to kmem_cache_create().
  * The ones marked DEBUG are only valid if CONFIG_DEBUG_SLAB is set.
  */
-#define SLAB_CONSISTENCY_CHECKS	0x00000100UL	/* DEBUG: Perform (expensive) checks on alloc/free */
-#define SLAB_RED_ZONE		0x00000400UL	/* DEBUG: Red zone objs in a cache */
-#define SLAB_POISON		0x00000800UL	/* DEBUG: Poison objects */
-#define SLAB_HWCACHE_ALIGN	0x00002000UL	/* Align objs on cache lines */
-#define SLAB_CACHE_DMA		0x00004000UL	/* Use GFP_DMA memory */
-#define SLAB_STORE_USER		0x00010000UL	/* DEBUG: Store the last owner for bug hunting */
-#define SLAB_PANIC		0x00040000UL	/* Panic if kmem_cache_create() fails */
+/* DEBUG: Perform (expensive) checks on alloc/free */
+#define SLAB_CONSISTENCY_CHECKS	((slab_flags_t __force)0x00000100UL)
+/* DEBUG: Red zone objs in a cache */
+#define SLAB_RED_ZONE		((slab_flags_t __force)0x00000400UL)
+/* DEBUG: Poison objects */
+#define SLAB_POISON		((slab_flags_t __force)0x00000800UL)
+/* Align objs on cache lines */
+#define SLAB_HWCACHE_ALIGN	((slab_flags_t __force)0x00002000UL)
+/* Use GFP_DMA memory */
+#define SLAB_CACHE_DMA		((slab_flags_t __force)0x00004000UL)
+/* DEBUG: Store the last owner for bug hunting */
+#define SLAB_STORE_USER		((slab_flags_t __force)0x00010000UL)
+/* Panic if kmem_cache_create() fails */
+#define SLAB_PANIC		((slab_flags_t __force)0x00040000UL)
 /*
  * SLAB_TYPESAFE_BY_RCU - **WARNING** READ THIS!
  *
@@ -65,44 +72,51 @@
  *
  * Note that SLAB_TYPESAFE_BY_RCU was originally named SLAB_DESTROY_BY_RCU.
  */
-#define SLAB_TYPESAFE_BY_RCU	0x00080000UL	/* Defer freeing slabs to RCU */
-#define SLAB_MEM_SPREAD		0x00100000UL	/* Spread some memory over cpuset */
-#define SLAB_TRACE		0x00200000UL	/* Trace allocations and frees */
+/* Defer freeing slabs to RCU */
+#define SLAB_TYPESAFE_BY_RCU	((slab_flags_t __force)0x00080000UL)
+/* Spread some memory over cpuset */
+#define SLAB_MEM_SPREAD		((slab_flags_t __force)0x00100000UL)
+/* Trace allocations and frees */
+#define SLAB_TRACE		((slab_flags_t __force)0x00200000UL)
 
 /* Flag to prevent checks on free */
 #ifdef CONFIG_DEBUG_OBJECTS
-# define SLAB_DEBUG_OBJECTS	0x00400000UL
+# define SLAB_DEBUG_OBJECTS	((slab_flags_t __force)0x00400000UL)
 #else
-# define SLAB_DEBUG_OBJECTS	0x00000000UL
+# define SLAB_DEBUG_OBJECTS	((slab_flags_t __force)0x00000000UL)
 #endif
 
-#define SLAB_NOLEAKTRACE	0x00800000UL	/* Avoid kmemleak tracing */
+/* Avoid kmemleak tracing */
+#define SLAB_NOLEAKTRACE	((slab_flags_t __force)0x00800000UL)
 
 /* Don't track use of uninitialized memory */
 #ifdef CONFIG_KMEMCHECK
-# define SLAB_NOTRACK		0x01000000UL
+# define SLAB_NOTRACK		((slab_flags_t __force)0x01000000UL)
 #else
-# define SLAB_NOTRACK		0x00000000UL
+# define SLAB_NOTRACK		((slab_flags_t __force)0x00000000UL)
 #endif
+/* Fault injection mark */
 #ifdef CONFIG_FAILSLAB
-# define SLAB_FAILSLAB		0x02000000UL	/* Fault injection mark */
+# define SLAB_FAILSLAB		((slab_flags_t __force)0x02000000UL)
 #else
-# define SLAB_FAILSLAB		0x00000000UL
+# define SLAB_FAILSLAB		((slab_flags_t __force)0x00000000UL)
 #endif
+/* Account to memcg */
 #if defined(CONFIG_MEMCG) && !defined(CONFIG_SLOB)
-# define SLAB_ACCOUNT		0x04000000UL	/* Account to memcg */
+# define SLAB_ACCOUNT		((slab_flags_t __force)0x04000000UL)
 #else
-# define SLAB_ACCOUNT		0x00000000UL
+# define SLAB_ACCOUNT		((slab_flags_t __force)0x00000000UL)
 #endif
 
 #ifdef CONFIG_KASAN
-#define SLAB_KASAN		0x08000000UL
+#define SLAB_KASAN		((slab_flags_t __force)0x08000000UL)
 #else
-#define SLAB_KASAN		0x00000000UL
+#define SLAB_KASAN		((slab_flags_t __force)0x00000000UL)
 #endif
 
 /* The following flags affect the page allocator grouping pages by mobility */
-#define SLAB_RECLAIM_ACCOUNT	0x00020000UL		/* Objects are reclaimable */
+/* Objects are reclaimable */
+#define SLAB_RECLAIM_ACCOUNT	((slab_flags_t __force)0x00020000UL)
 #define SLAB_TEMPORARY		SLAB_RECLAIM_ACCOUNT	/* Objects are short-lived */
 /*
  * ZERO_SIZE_PTR will be returned for zero sized kmalloc requests.
@@ -128,7 +142,7 @@ void __init kmem_cache_init(void);
 bool slab_is_available(void);
 
 struct kmem_cache *kmem_cache_create(const char *, size_t, size_t,
-			unsigned long,
+			slab_flags_t,
 			void (*)(void *));
 void kmem_cache_destroy(struct kmem_cache *);
 int kmem_cache_shrink(struct kmem_cache *);
diff --git a/include/linux/slab_def.h b/include/linux/slab_def.h
index 8f7d2b1656d2..072e46e9e1d5 100644
--- a/include/linux/slab_def.h
+++ b/include/linux/slab_def.h
@@ -20,7 +20,7 @@ struct kmem_cache {
 	struct reciprocal_value reciprocal_buffer_size;
 /* 2) touched by every alloc & free from the backend */
 
-	unsigned int flags;		/* constant flags */
+	slab_flags_t flags;		/* constant flags */
 	unsigned int num;		/* # of objs per slab */
 
 /* 3) cache_grow/shrink */
diff --git a/include/linux/slub_def.h b/include/linux/slub_def.h
index 39fa09bcde23..0adae162dc8f 100644
--- a/include/linux/slub_def.h
+++ b/include/linux/slub_def.h
@@ -82,7 +82,7 @@ struct kmem_cache_order_objects {
 struct kmem_cache {
 	struct kmem_cache_cpu __percpu *cpu_slab;
 	/* Used for retriving partial slabs etc */
-	unsigned long flags;
+	slab_flags_t flags;
 	unsigned long min_partial;
 	int size;		/* The size of an object including meta data */
 	int object_size;	/* The size of an object without meta data */
diff --git a/include/linux/types.h b/include/linux/types.h
index 34fce54e4f1b..732b52c2eae4 100644
--- a/include/linux/types.h
+++ b/include/linux/types.h
@@ -156,6 +156,7 @@ typedef u32 dma_addr_t;
 #endif
 
 typedef unsigned __bitwise gfp_t;
+typedef unsigned long __bitwise slab_flags_t;
 typedef unsigned __bitwise fmode_t;
 
 #ifdef CONFIG_PHYS_ADDR_T_64BIT