mm.h

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/*
 * linux/compr_mm.h
 *
 * Memory management for pre-boot and ramdisk uncompressors
 *
 * Authors: Alain Knaff <[email protected]>
 *
 */

#ifndef DECOMPR_MM_H
#define DECOMPR_MM_H

#ifdef STATIC

/* Code active when included from pre-boot environment: */

/*
 * Some architectures want to ensure there is no local data in their
 * pre-boot environment, so that data can arbitrarily relocated (via
 * GOT references).  This is achieved by defining STATIC_RW_DATA to
 * be null.
 */
#ifndef STATIC_RW_DATA
#define STATIC_RW_DATA static
#endif

/* A trivial malloc implementation, adapted from
 *  malloc by Hannu Savolainen 1993 and Matthias Urlichs 1994
 */
STATIC_RW_DATA unsigned long malloc_ptr;
STATIC_RW_DATA int malloc_count;

static void *malloc(int size)
{
    void *p;

    if (size < 0)
        return NULL;
    if (!malloc_ptr)
        malloc_ptr = free_mem_ptr;

    malloc_ptr = (malloc_ptr + 3) & ~3;     /* Align */

    p = (void *)malloc_ptr;
    malloc_ptr += size;

    if (free_mem_end_ptr && malloc_ptr >= free_mem_end_ptr)
        return NULL;

    malloc_count++;
    return p;
}

static void free(void *where)
{
    malloc_count--;
    if (!malloc_count)
        malloc_ptr = free_mem_ptr;
}

#define large_malloc(a) malloc(a)
#define large_free(a) free(a)

#define INIT

#else /* STATIC */

/* Code active when compiled standalone for use when loading ramdisk: */

#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/string.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>

/* Use defines rather than static inline in order to avoid spurious
 * warnings when not needed (indeed large_malloc / large_free are not
 * needed by inflate */

#define malloc(a) kmalloc(a, GFP_KERNEL)
#define free(a) kfree(a)

#define large_malloc(a) vmalloc(a)
#define large_free(a) vfree(a)

#define INIT __init
#define STATIC

#include <linux/init.h>

#endif /* STATIC */

#endif /* DECOMPR_MM_H */