X-Git-Url: http://pilppa.org/gitweb/?a=blobdiff_plain;f=include%2Flinux%2Fslub_def.h;h=6207a3d8da7150abbb8c1361331b5f4945162b66;hb=82afee684fe3badaf5ee3fc5b6fda687d558bfb5;hp=ea27065e80e636d6a9b41e7a49144186cf79020d;hpb=805f53f085346b6765eda02820721a14ce0d644f;p=linux-2.6-omap-h63xx.git

diff --git a/include/linux/slub_def.h b/include/linux/slub_def.h
index ea27065e80e..6207a3d8da7 100644
--- a/include/linux/slub_def.h
+++ b/include/linux/slub_def.h
@@ -28,7 +28,7 @@ struct kmem_cache {
 	int size;		/* The size of an object including meta data */
 	int objsize;		/* The size of an object without meta data */
 	int offset;		/* Free pointer offset. */
-	unsigned int order;
+	int order;
 
 	/*
 	 * Avoid an extra cache line for UP, SMP and for the node local to
@@ -40,7 +40,6 @@ struct kmem_cache {
 	int objects;		/* Number of objects in slab */
 	int refcount;		/* Refcount for slab cache destroy */
 	void (*ctor)(void *, struct kmem_cache *, unsigned long);
-	void (*dtor)(void *, struct kmem_cache *, unsigned long);
 	int inuse;		/* Offset to metadata */
 	int align;		/* Alignment */
 	const char *name;	/* Name (only for display!) */
@@ -57,18 +56,14 @@ struct kmem_cache {
 /*
  * Kmalloc subsystem.
  */
-#define KMALLOC_SHIFT_LOW 3
-
-#ifdef CONFIG_LARGE_ALLOCS
-#define KMALLOC_SHIFT_HIGH 25
-#else
-#if !defined(CONFIG_MMU) || NR_CPUS > 512 || MAX_NUMNODES > 256
-#define KMALLOC_SHIFT_HIGH 20
+#if defined(ARCH_KMALLOC_MINALIGN) && ARCH_KMALLOC_MINALIGN > 8
+#define KMALLOC_MIN_SIZE ARCH_KMALLOC_MINALIGN
 #else
-#define KMALLOC_SHIFT_HIGH 18
-#endif
+#define KMALLOC_MIN_SIZE 8
 #endif
 
+#define KMALLOC_SHIFT_LOW ilog2(KMALLOC_MIN_SIZE)
+
 /*
  * We keep the general caches in an array of slab caches that are used for
  * 2^x bytes of allocations.
@@ -79,13 +74,16 @@ extern struct kmem_cache kmalloc_caches[KMALLOC_SHIFT_HIGH + 1];
  * Sorry that the following has to be that ugly but some versions of GCC
  * have trouble with constant propagation and loops.
  */
-static inline int kmalloc_index(int size)
+static inline int kmalloc_index(size_t size)
 {
-	/*
-	 * We should return 0 if size == 0 but we use the smallest object
-	 * here for SLAB legacy reasons.
-	 */
-	WARN_ON_ONCE(size == 0);
+	if (!size)
+		return 0;
+
+	if (size > KMALLOC_MAX_SIZE)
+		return -1;
+
+	if (size <= KMALLOC_MIN_SIZE)
+		return KMALLOC_SHIFT_LOW;
 
 	if (size > 64 && size <= 96)
 		return 1;
@@ -107,17 +105,13 @@ static inline int kmalloc_index(int size)
 	if (size <=  64 * 1024) return 16;
 	if (size <= 128 * 1024) return 17;
 	if (size <= 256 * 1024) return 18;
-#if KMALLOC_SHIFT_HIGH > 18
 	if (size <=  512 * 1024) return 19;
 	if (size <= 1024 * 1024) return 20;
-#endif
-#if KMALLOC_SHIFT_HIGH > 20
 	if (size <=  2 * 1024 * 1024) return 21;
 	if (size <=  4 * 1024 * 1024) return 22;
 	if (size <=  8 * 1024 * 1024) return 23;
 	if (size <= 16 * 1024 * 1024) return 24;
 	if (size <= 32 * 1024 * 1024) return 25;
-#endif
 	return -1;
 
 /*
@@ -142,7 +136,12 @@ static inline struct kmem_cache *kmalloc_slab(size_t size)
 	if (index == 0)
 		return NULL;
 
-	if (index < 0) {
+	/*
+	 * This function only gets expanded if __builtin_constant_p(size), so
+	 * testing it here shouldn't be needed.  But some versions of gcc need
+	 * help.
+	 */
+	if (__builtin_constant_p(size) && index < 0) {
 		/*
 		 * Generate a link failure. Would be great if we could
 		 * do something to stop the compile here.
@@ -160,13 +159,25 @@ static inline struct kmem_cache *kmalloc_slab(size_t size)
 #define SLUB_DMA 0
 #endif
 
+
+/*
+ * ZERO_SIZE_PTR will be returned for zero sized kmalloc requests.
+ *
+ * Dereferencing ZERO_SIZE_PTR will lead to a distinct access fault.
+ *
+ * ZERO_SIZE_PTR can be passed to kfree though in the same way that NULL can.
+ * Both make kfree a no-op.
+ */
+#define ZERO_SIZE_PTR ((void *)16)
+
+
 static inline void *kmalloc(size_t size, gfp_t flags)
 {
 	if (__builtin_constant_p(size) && !(flags & SLUB_DMA)) {
 		struct kmem_cache *s = kmalloc_slab(size);
 
 		if (!s)
-			return NULL;
+			return ZERO_SIZE_PTR;
 
 		return kmem_cache_alloc(s, flags);
 	} else
@@ -179,7 +190,7 @@ static inline void *kzalloc(size_t size, gfp_t flags)
 		struct kmem_cache *s = kmalloc_slab(size);
 
 		if (!s)
-			return NULL;
+			return ZERO_SIZE_PTR;
 
 		return kmem_cache_zalloc(s, flags);
 	} else
@@ -195,7 +206,7 @@ static inline void *kmalloc_node(size_t size, gfp_t flags, int node)
 		struct kmem_cache *s = kmalloc_slab(size);
 
 		if (!s)
-			return NULL;
+			return ZERO_SIZE_PTR;
 
 		return kmem_cache_alloc_node(s, flags, node);
 	} else