aha/include/linux/kmemcheck.h
Jan Beulich 8c87df457c BUILD_BUG_ON(): fix it and a couple of bogus uses of it
gcc permitting variable length arrays makes the current construct used for
BUILD_BUG_ON() useless, as that doesn't produce any diagnostic if the
controlling expression isn't really constant.  Instead, this patch makes
it so that a bit field gets used here.  Consequently, those uses where the
condition isn't really constant now also need fixing.

Note that in the gfp.h, kmemcheck.h, and virtio_config.h cases
MAYBE_BUILD_BUG_ON() really just serves documentation purposes - even if
the expression is compile time constant (__builtin_constant_p() yields
true), the array is still deemed of variable length by gcc, and hence the
whole expression doesn't have the intended effect.

[akpm@linux-foundation.org: make arch/sparc/include/asm/vio.h compile]
[akpm@linux-foundation.org: more nonsensical assertions in tpm.c..]
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Rajiv Andrade <srajiv@linux.vnet.ibm.com>
Cc: Mimi Zohar <zohar@us.ibm.com>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-23 07:39:29 -07:00

165 lines
4.3 KiB
C

#ifndef LINUX_KMEMCHECK_H
#define LINUX_KMEMCHECK_H
#include <linux/mm_types.h>
#include <linux/types.h>
#ifdef CONFIG_KMEMCHECK
extern int kmemcheck_enabled;
/* The slab-related functions. */
void kmemcheck_alloc_shadow(struct page *page, int order, gfp_t flags, int node);
void kmemcheck_free_shadow(struct page *page, int order);
void kmemcheck_slab_alloc(struct kmem_cache *s, gfp_t gfpflags, void *object,
size_t size);
void kmemcheck_slab_free(struct kmem_cache *s, void *object, size_t size);
void kmemcheck_pagealloc_alloc(struct page *p, unsigned int order,
gfp_t gfpflags);
void kmemcheck_show_pages(struct page *p, unsigned int n);
void kmemcheck_hide_pages(struct page *p, unsigned int n);
bool kmemcheck_page_is_tracked(struct page *p);
void kmemcheck_mark_unallocated(void *address, unsigned int n);
void kmemcheck_mark_uninitialized(void *address, unsigned int n);
void kmemcheck_mark_initialized(void *address, unsigned int n);
void kmemcheck_mark_freed(void *address, unsigned int n);
void kmemcheck_mark_unallocated_pages(struct page *p, unsigned int n);
void kmemcheck_mark_uninitialized_pages(struct page *p, unsigned int n);
void kmemcheck_mark_initialized_pages(struct page *p, unsigned int n);
int kmemcheck_show_addr(unsigned long address);
int kmemcheck_hide_addr(unsigned long address);
bool kmemcheck_is_obj_initialized(unsigned long addr, size_t size);
#else
#define kmemcheck_enabled 0
static inline void
kmemcheck_alloc_shadow(struct page *page, int order, gfp_t flags, int node)
{
}
static inline void
kmemcheck_free_shadow(struct page *page, int order)
{
}
static inline void
kmemcheck_slab_alloc(struct kmem_cache *s, gfp_t gfpflags, void *object,
size_t size)
{
}
static inline void kmemcheck_slab_free(struct kmem_cache *s, void *object,
size_t size)
{
}
static inline void kmemcheck_pagealloc_alloc(struct page *p,
unsigned int order, gfp_t gfpflags)
{
}
static inline bool kmemcheck_page_is_tracked(struct page *p)
{
return false;
}
static inline void kmemcheck_mark_unallocated(void *address, unsigned int n)
{
}
static inline void kmemcheck_mark_uninitialized(void *address, unsigned int n)
{
}
static inline void kmemcheck_mark_initialized(void *address, unsigned int n)
{
}
static inline void kmemcheck_mark_freed(void *address, unsigned int n)
{
}
static inline void kmemcheck_mark_unallocated_pages(struct page *p,
unsigned int n)
{
}
static inline void kmemcheck_mark_uninitialized_pages(struct page *p,
unsigned int n)
{
}
static inline void kmemcheck_mark_initialized_pages(struct page *p,
unsigned int n)
{
}
static inline bool kmemcheck_is_obj_initialized(unsigned long addr, size_t size)
{
return true;
}
#endif /* CONFIG_KMEMCHECK */
/*
* Bitfield annotations
*
* How to use: If you have a struct using bitfields, for example
*
* struct a {
* int x:8, y:8;
* };
*
* then this should be rewritten as
*
* struct a {
* kmemcheck_bitfield_begin(flags);
* int x:8, y:8;
* kmemcheck_bitfield_end(flags);
* };
*
* Now the "flags_begin" and "flags_end" members may be used to refer to the
* beginning and end, respectively, of the bitfield (and things like
* &x.flags_begin is allowed). As soon as the struct is allocated, the bit-
* fields should be annotated:
*
* struct a *a = kmalloc(sizeof(struct a), GFP_KERNEL);
* kmemcheck_annotate_bitfield(a, flags);
*
* Note: We provide the same definitions for both kmemcheck and non-
* kmemcheck kernels. This makes it harder to introduce accidental errors. It
* is also allowed to pass NULL pointers to kmemcheck_annotate_bitfield().
*/
#define kmemcheck_bitfield_begin(name) \
int name##_begin[0];
#define kmemcheck_bitfield_end(name) \
int name##_end[0];
#define kmemcheck_annotate_bitfield(ptr, name) \
do { \
int _n; \
\
if (!ptr) \
break; \
\
_n = (long) &((ptr)->name##_end) \
- (long) &((ptr)->name##_begin); \
MAYBE_BUILD_BUG_ON(_n < 0); \
\
kmemcheck_mark_initialized(&((ptr)->name##_begin), _n); \
} while (0)
#define kmemcheck_annotate_variable(var) \
do { \
kmemcheck_mark_initialized(&(var), sizeof(var)); \
} while (0) \
#endif /* LINUX_KMEMCHECK_H */