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12#include <stddef.h>
13#include "types.h"
14#include "page.h"
15#include "string.h"
16#include "ops.h"
17
18#define ENTRY_BEEN_USED 0x01
19#define ENTRY_IN_USE 0x02
20
21static struct alloc_info {
22 unsigned long flags;
23 unsigned long base;
24 unsigned long size;
25} *alloc_tbl;
26
27static unsigned long tbl_entries;
28static unsigned long alloc_min;
29static unsigned long next_base;
30static unsigned long space_left;
31
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35
36
37static void *simple_malloc(unsigned long size)
38{
39 unsigned long i;
40 struct alloc_info *p = alloc_tbl;
41
42 if (size == 0)
43 goto err_out;
44
45 size = _ALIGN_UP(size, alloc_min);
46
47 for (i=0; i<tbl_entries; i++, p++)
48 if (!(p->flags & ENTRY_BEEN_USED)) {
49 if (size <= space_left) {
50 p->base = next_base;
51 p->size = size;
52 p->flags = ENTRY_BEEN_USED | ENTRY_IN_USE;
53 next_base += size;
54 space_left -= size;
55 return (void *)p->base;
56 }
57 goto err_out;
58 }
59
60 else if (!(p->flags & ENTRY_IN_USE) && (size <= p->size)) {
61 p->flags |= ENTRY_IN_USE;
62 return (void *)p->base;
63 }
64err_out:
65 return NULL;
66}
67
68static struct alloc_info *simple_find_entry(void *ptr)
69{
70 unsigned long i;
71 struct alloc_info *p = alloc_tbl;
72
73 for (i=0; i<tbl_entries; i++,p++) {
74 if (!(p->flags & ENTRY_BEEN_USED))
75 break;
76 if ((p->flags & ENTRY_IN_USE) &&
77 (p->base == (unsigned long)ptr))
78 return p;
79 }
80 return NULL;
81}
82
83static void simple_free(void *ptr)
84{
85 struct alloc_info *p = simple_find_entry(ptr);
86
87 if (p != NULL)
88 p->flags &= ~ENTRY_IN_USE;
89}
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96
97static void *simple_realloc(void *ptr, unsigned long size)
98{
99 struct alloc_info *p;
100 void *new;
101
102 if (size == 0) {
103 simple_free(ptr);
104 return NULL;
105 }
106
107 if (ptr == NULL)
108 return simple_malloc(size);
109
110 p = simple_find_entry(ptr);
111 if (p == NULL)
112 return NULL;
113 if (size <= p->size)
114 return ptr;
115
116 new = simple_malloc(size);
117 memcpy(new, ptr, p->size);
118 simple_free(ptr);
119 return new;
120}
121
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125
126void *simple_alloc_init(char *base, unsigned long heap_size,
127 unsigned long granularity, unsigned long max_allocs)
128{
129 unsigned long heap_base, tbl_size;
130
131 heap_size = _ALIGN_UP(heap_size, granularity);
132 alloc_min = granularity;
133 tbl_entries = max_allocs;
134
135 tbl_size = tbl_entries * sizeof(struct alloc_info);
136
137 alloc_tbl = (struct alloc_info *)_ALIGN_UP((unsigned long)base, 8);
138 memset(alloc_tbl, 0, tbl_size);
139
140 heap_base = _ALIGN_UP((unsigned long)alloc_tbl + tbl_size, alloc_min);
141
142 next_base = heap_base;
143 space_left = heap_size;
144
145 platform_ops.malloc = simple_malloc;
146 platform_ops.free = simple_free;
147 platform_ops.realloc = simple_realloc;
148
149 return (void *)(heap_base + heap_size);
150}
151