kmemcheck.h

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#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);

/*
 * 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);
 */
#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);        \
        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)                         \

#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;
}

#define kmemcheck_bitfield_begin(name)
#define kmemcheck_bitfield_end(name)
#define kmemcheck_annotate_bitfield(ptr, name)  \
    do {                    \
    } while (0)

#define kmemcheck_annotate_variable(var)    \
    do {                    \
    } while (0)

#endif /* CONFIG_KMEMCHECK */

#endif /* LINUX_KMEMCHECK_H */