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 */
39 STATIC_RW_DATA unsigned long malloc_ptr;
40 STATIC_RW_DATA int malloc_count;
41
42 MALLOC_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
63 MALLOC_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
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