1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * linux/compr_mm.h
4 *
5 * Memory management for pre-boot and ramdisk uncompressors
6 *
7 * Authors: Alain Knaff <alain@knaff.lu>
8 *
9 */
10
11#ifndef DECOMPR_MM_H
12#define DECOMPR_MM_H
13
14#ifdef STATIC
15
16/* Code active when included from pre-boot environment: */
17
18/*
19 * Some architectures want to ensure there is no local data in their
20 * pre-boot environment, so that data can arbitrarily relocated (via
21 * GOT references). This is achieved by defining STATIC_RW_DATA to
22 * be null.
23 */
24#ifndef STATIC_RW_DATA
25#define STATIC_RW_DATA static
26#endif
27
28/*
29 * When an architecture needs to share the malloc()/free() implementation
30 * between compilation units, it needs to have non-local visibility.
31 */
32#ifndef MALLOC_VISIBLE
33#define MALLOC_VISIBLE static
34#endif
35
36/* A trivial malloc implementation, adapted from
37 * malloc by Hannu Savolainen 1993 and Matthias Urlichs 1994
38 */
39STATIC_RW_DATA unsigned long malloc_ptr;
40STATIC_RW_DATA int malloc_count;
41
42MALLOC_VISIBLE void *malloc(int size)
43{
44 void *p;
45
46 if (size < 0)
47 return NULL;
48 if (!malloc_ptr)
49 malloc_ptr = free_mem_ptr;
50
51 malloc_ptr = (malloc_ptr + 7) & ~7; /* Align */
52
53 p = (void *)malloc_ptr;
54 malloc_ptr += size;
55
56 if (free_mem_end_ptr && malloc_ptr >= free_mem_end_ptr)
57 return NULL;
58
59 malloc_count++;
60 return p;
61}
62
63MALLOC_VISIBLE void free(void *where)
64{
65 malloc_count--;
66 if (!malloc_count)
67 malloc_ptr = free_mem_ptr;
68}
69
70#define large_malloc(a) malloc(a)
71#define large_free(a) free(a)
72
73#define INIT
74
75#else /* STATIC */
76
77/* Code active when compiled standalone for use when loading ramdisk: */
78
79#include <linux/kernel.h>
80#include <linux/fs.h>
81#include <linux/string.h>
82#include <linux/slab.h>
83#include <linux/vmalloc.h>
84
85/* Use defines rather than static inline in order to avoid spurious
86 * warnings when not needed (indeed large_malloc / large_free are not
87 * needed by inflate */
88
89#define malloc(a) kmalloc(a, GFP_KERNEL)
90#define free(a) kfree(a)
91
92#define large_malloc(a) vmalloc(a)
93#define large_free(a) vfree(a)
94
95#define INIT __init
96#define STATIC
97
98#include <linux/init.h>
99
100#endif /* STATIC */
101
102#endif /* DECOMPR_MM_H */
103