Subversion Repositories HelenOS

Rev

Rev 1787 | Go to most recent revision | 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>
1868 jermar 39 
#include <types.h>
978 jermar 40 
 
1868 jermar 41 
/**
42 
 * Either 4*256M on 32-bit architecures or 16*256M on 64-bit architectures.
43 
 */
44 
#define MAX_HEAP_SIZE   (sizeof(uintptr_t)<<28)
45 
 
1228 jermar 46 
/** Create address space area.
1033 jermar 47 
 *
48 
 * @param address Virtual address where to place new address space area.
49 
 * @param size Size of the area.
50 
 * @param flags Flags describing type of the area.
51 
 *
52 
 * @return address on success, (void *) -1 otherwise.
53 
 */
1228 jermar 54 
void *as_area_create(void *address, size_t size, int flags)
978 jermar 55 
{
1228 jermar 56 
    return (void *) __SYSCALL3(SYS_AS_AREA_CREATE, (sysarg_t ) address, (sysarg_t) size, (sysarg_t) flags);
1033 jermar 57 
}
58 
 
1228 jermar 59 
/** Resize address space area.
1033 jermar 60 
 *
61 
 * @param address Virtual address pointing into already existing address space area.
62 
 * @param size New requested size of the area.
63 
 * @param flags Currently unused.
64 
 *
1307 jermar 65 
 * @return Zero on success or a code from @ref errno.h on failure.
1033 jermar 66 
 */
1307 jermar 67 
int as_area_resize(void *address, size_t size, int flags)
1033 jermar 68 
{
1307 jermar 69 
    return __SYSCALL3(SYS_AS_AREA_RESIZE, (sysarg_t ) address, (sysarg_t) size, (sysarg_t) flags);
978 jermar 70 
}
985 palkovsky 71 
 
1307 jermar 72 
/** Destroy address space area.
73 
 *
74 
 * @param address Virtual address pointing into the address space area being destroyed.
75 
 *
76 
 * @return Zero on success or a code from @ref errno.h on failure.
77 
 */
78 
int as_area_destroy(void *address)
79 
{
80 
    return __SYSCALL1(SYS_AS_AREA_DESTROY, (sysarg_t ) address);
81 
}
82 
 
985 palkovsky 83 
static size_t heapsize = 0;
1719 decky 84 
static size_t maxheapsize = (size_t) (-1);
1501 palkovsky 85 
 
86 
static void * last_allocated = 0;
87 
 
985 palkovsky 88 
/* Start of heap linker symbol */
89 
extern char _heap;
90 
 
91 
/** Sbrk emulation
92 
 *
1653 cejka 93 
 * @param incr New area that should be allocated or negative,
985 palkovsky 94 
               if it should be shrinked
95 
 * @return Pointer to newly allocated area
96 
 */
97 
void *sbrk(ssize_t incr)
98 
{
1307 jermar 99 
    int rc;
985 palkovsky 100 
    void *res;
1719 decky 101 
 
985 palkovsky 102 
    /* Check for invalid values */
103 
    if (incr < 0 && -incr > heapsize)
104 
        return NULL;
1719 decky 105 
 
985 palkovsky 106 
    /* Check for too large value */
107 
    if (incr > 0 && incr+heapsize < heapsize)
108 
        return NULL;
1719 decky 109 
 
985 palkovsky 110 
    /* Check for too small values */
111 
    if (incr < 0 && incr+heapsize > heapsize)
112 
        return NULL;
1719 decky 113 
 
1363 vana 114 
    /* Check for user limit */
1719 decky 115 
    if ((maxheapsize != (size_t) (-1)) && (heapsize + incr) > maxheapsize)
116 
        return NULL;
117 
 
118 
    rc = as_area_resize(&_heap, heapsize + incr, 0);
1307 jermar 119 
    if (rc != 0)
985 palkovsky 120 
        return NULL;
999 palkovsky 121 
 
122 
    /* Compute start of new area */
1719 decky 123 
    res = (void *) &_heap + heapsize;
999 palkovsky 124 
 
985 palkovsky 125 
    heapsize += incr;
999 palkovsky 126 
 
985 palkovsky 127 
    return res;
128 
}
1363 vana 129 
 
1501 palkovsky 130 
/** Set maximum heap size and return pointer just after the heap */
1363 vana 131 
void *set_maxheapsize(size_t mhs)
132 
{
1719 decky 133 
    maxheapsize = mhs;
1363 vana 134 
    /* Return pointer to area not managed by sbrk */
1719 decky 135 
    return ((void *) &_heap + maxheapsize);
1363 vana 136 
 
137 
}
1501 palkovsky 138 
 
139 
/** Return pointer to some unmapped area, where fits new as_area
140 
 *
141 
 * TODO: make some first_fit/... algorithm, we are now just incrementing
142 
 *       the pointer to last area
143 
 */
144 
void * as_get_mappable_page(size_t sz)
145 
{
146 
    void *res;
147 
 
148 
    /* Set heapsize to some meaningful value */
149 
    if (maxheapsize == -1)
1868 jermar 150 
        set_maxheapsize(MAX_HEAP_SIZE);
1719 decky 151 
 
1501 palkovsky 152 
    if (!last_allocated)
1719 decky 153 
        last_allocated = (void *) ALIGN_UP((void *) &_heap + maxheapsize, PAGE_SIZE);
1501 palkovsky 154 
 
155 
    sz = ALIGN_UP(sz, PAGE_SIZE);
156 
    res = last_allocated;
157 
    last_allocated += sz;
158 
 
159 
    return res;
160 
}
1653 cejka 161 
 
1719 decky 162 
/** @}
1653 cejka 163 
 */