Subversion Repositories HelenOS-historic

Rev

Rev 1653 | Details | Compare with Previous | Last modification | View Log | RSS feed

Rev Author Line No. Line
978 jermar 1
/*
2
 * Copyright (C) 2006 Jakub Jermar
3
 * All rights reserved.
4
 *
5
 * Redistribution and use in source and binary forms, with or without
6
 * modification, are permitted provided that the following conditions
7
 * are met:
8
 *
9
 * - Redistributions of source code must retain the above copyright
10
 *   notice, this list of conditions and the following disclaimer.
11
 * - Redistributions in binary form must reproduce the above copyright
12
 *   notice, this list of conditions and the following disclaimer in the
13
 *   documentation and/or other materials provided with the distribution.
14
 * - The name of the author may not be used to endorse or promote products
15
 *   derived from this software without specific prior written permission.
16
 *
17
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1653 cejka 27
 */
28
 
1719 decky 29
/** @addtogroup libc
1653 cejka 30
 * @{
31
 */
32
/** @file
978 jermar 33
 */
34
 
1250 jermar 35
#include <as.h>
978 jermar 36
#include <libc.h>
37
#include <unistd.h>
1501 palkovsky 38
#include <align.h>
978 jermar 39
 
1228 jermar 40
/** Create address space area.
1033 jermar 41
 *
42
 * @param address Virtual address where to place new address space area.
43
 * @param size Size of the area.
44
 * @param flags Flags describing type of the area.
45
 *
46
 * @return address on success, (void *) -1 otherwise.
47
 */
1228 jermar 48
void *as_area_create(void *address, size_t size, int flags)
978 jermar 49
{
1228 jermar 50
    return (void *) __SYSCALL3(SYS_AS_AREA_CREATE, (sysarg_t ) address, (sysarg_t) size, (sysarg_t) flags);
1033 jermar 51
}
52
 
1228 jermar 53
/** Resize address space area.
1033 jermar 54
 *
55
 * @param address Virtual address pointing into already existing address space area.
56
 * @param size New requested size of the area.
57
 * @param flags Currently unused.
58
 *
1307 jermar 59
 * @return Zero on success or a code from @ref errno.h on failure.
1033 jermar 60
 */
1307 jermar 61
int as_area_resize(void *address, size_t size, int flags)
1033 jermar 62
{
1307 jermar 63
    return __SYSCALL3(SYS_AS_AREA_RESIZE, (sysarg_t ) address, (sysarg_t) size, (sysarg_t) flags);
978 jermar 64
}
985 palkovsky 65
 
1307 jermar 66
/** Destroy address space area.
67
 *
68
 * @param address Virtual address pointing into the address space area being destroyed.
69
 *
70
 * @return Zero on success or a code from @ref errno.h on failure.
71
 */
72
int as_area_destroy(void *address)
73
{
74
    return __SYSCALL1(SYS_AS_AREA_DESTROY, (sysarg_t ) address);
75
}
76
 
985 palkovsky 77
static size_t heapsize = 0;
1719 decky 78
static size_t maxheapsize = (size_t) (-1);
1501 palkovsky 79
 
80
static void * last_allocated = 0;
81
 
985 palkovsky 82
/* Start of heap linker symbol */
83
extern char _heap;
84
 
85
/** Sbrk emulation
86
 *
1653 cejka 87
 * @param incr New area that should be allocated or negative,
985 palkovsky 88
               if it should be shrinked
89
 * @return Pointer to newly allocated area
90
 */
91
void *sbrk(ssize_t incr)
92
{
1307 jermar 93
    int rc;
985 palkovsky 94
    void *res;
1719 decky 95
 
985 palkovsky 96
    /* Check for invalid values */
97
    if (incr < 0 && -incr > heapsize)
98
        return NULL;
1719 decky 99
 
985 palkovsky 100
    /* Check for too large value */
101
    if (incr > 0 && incr+heapsize < heapsize)
102
        return NULL;
1719 decky 103
 
985 palkovsky 104
    /* Check for too small values */
105
    if (incr < 0 && incr+heapsize > heapsize)
106
        return NULL;
1719 decky 107
 
1363 vana 108
    /* Check for user limit */
1719 decky 109
    if ((maxheapsize != (size_t) (-1)) && (heapsize + incr) > maxheapsize)
110
        return NULL;
111
 
112
    rc = as_area_resize(&_heap, heapsize + incr, 0);
1307 jermar 113
    if (rc != 0)
985 palkovsky 114
        return NULL;
999 palkovsky 115
 
116
    /* Compute start of new area */
1719 decky 117
    res = (void *) &_heap + heapsize;
999 palkovsky 118
 
985 palkovsky 119
    heapsize += incr;
999 palkovsky 120
 
985 palkovsky 121
    return res;
122
}
1363 vana 123
 
1501 palkovsky 124
/** Set maximum heap size and return pointer just after the heap */
1363 vana 125
void *set_maxheapsize(size_t mhs)
126
{
1719 decky 127
    maxheapsize = mhs;
1363 vana 128
    /* Return pointer to area not managed by sbrk */
1719 decky 129
    return ((void *) &_heap + maxheapsize);
1363 vana 130
 
131
}
1501 palkovsky 132
 
133
/** Return pointer to some unmapped area, where fits new as_area
134
 *
135
 * TODO: make some first_fit/... algorithm, we are now just incrementing
136
 *       the pointer to last area
137
 */
138
void * as_get_mappable_page(size_t sz)
139
{
140
    void *res;
141
 
142
    /* Set heapsize to some meaningful value */
143
    if (maxheapsize == -1)
1719 decky 144
        set_maxheapsize(ALIGN_UP(USER_ADDRESS_SPACE_SIZE_ARCH >> 1, PAGE_SIZE));
145
 
1501 palkovsky 146
    if (!last_allocated)
1719 decky 147
        last_allocated = (void *) ALIGN_UP((void *) &_heap + maxheapsize, PAGE_SIZE);
1501 palkovsky 148
 
149
    sz = ALIGN_UP(sz, PAGE_SIZE);
150
    res = last_allocated;
151
    last_allocated += sz;
152
 
153
    return res;
154
}
1653 cejka 155
 
1719 decky 156
/** @}
1653 cejka 157
 */