| 0,0 → 1,157 |
|---|
| /* |
| * Copyright (C) 2006 Jakub Jermar |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * |
| * - Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * - Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * - The name of the author may not be used to endorse or promote products |
| * derived from this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
| * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
| * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
| * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| /** @addtogroup libc |
| * @{ |
| */ |
| /** @file |
| */ |
| |
| #include <as.h> |
| #include <libc.h> |
| #include <unistd.h> |
| #include <align.h> |
| |
| /** Create address space area. |
| * |
| * @param address Virtual address where to place new address space area. |
| * @param size Size of the area. |
| * @param flags Flags describing type of the area. |
| * |
| * @return address on success, (void *) -1 otherwise. |
| */ |
| void *as_area_create(void *address, size_t size, int flags) |
| { |
| return (void *) __SYSCALL3(SYS_AS_AREA_CREATE, (sysarg_t ) address, (sysarg_t) size, (sysarg_t) flags); |
| } |
| |
| /** Resize address space area. |
| * |
| * @param address Virtual address pointing into already existing address space area. |
| * @param size New requested size of the area. |
| * @param flags Currently unused. |
| * |
| * @return Zero on success or a code from @ref errno.h on failure. |
| */ |
| int as_area_resize(void *address, size_t size, int flags) |
| { |
| return __SYSCALL3(SYS_AS_AREA_RESIZE, (sysarg_t ) address, (sysarg_t) size, (sysarg_t) flags); |
| } |
| |
| /** Destroy address space area. |
| * |
| * @param address Virtual address pointing into the address space area being destroyed. |
| * |
| * @return Zero on success or a code from @ref errno.h on failure. |
| */ |
| int as_area_destroy(void *address) |
| { |
| return __SYSCALL1(SYS_AS_AREA_DESTROY, (sysarg_t ) address); |
| } |
| |
| static size_t heapsize = 0; |
| static size_t maxheapsize = (size_t) (-1); |
| |
| static void * last_allocated = 0; |
| |
| /* Start of heap linker symbol */ |
| extern char _heap; |
| |
| /** Sbrk emulation |
| * |
| * @param incr New area that should be allocated or negative, |
| if it should be shrinked |
| * @return Pointer to newly allocated area |
| */ |
| void *sbrk(ssize_t incr) |
| { |
| int rc; |
| void *res; |
| |
| /* Check for invalid values */ |
| if (incr < 0 && -incr > heapsize) |
| return NULL; |
| |
| /* Check for too large value */ |
| if (incr > 0 && incr+heapsize < heapsize) |
| return NULL; |
| |
| /* Check for too small values */ |
| if (incr < 0 && incr+heapsize > heapsize) |
| return NULL; |
| |
| /* Check for user limit */ |
| if ((maxheapsize != (size_t) (-1)) && (heapsize + incr) > maxheapsize) |
| return NULL; |
| |
| rc = as_area_resize(&_heap, heapsize + incr, 0); |
| if (rc != 0) |
| return NULL; |
| |
| /* Compute start of new area */ |
| res = (void *) &_heap + heapsize; |
| |
| heapsize += incr; |
| |
| return res; |
| } |
| |
| /** Set maximum heap size and return pointer just after the heap */ |
| void *set_maxheapsize(size_t mhs) |
| { |
| maxheapsize = mhs; |
| /* Return pointer to area not managed by sbrk */ |
| return ((void *) &_heap + maxheapsize); |
| |
| } |
| |
| /** Return pointer to some unmapped area, where fits new as_area |
| * |
| * TODO: make some first_fit/... algorithm, we are now just incrementing |
| * the pointer to last area |
| */ |
| void * as_get_mappable_page(size_t sz) |
| { |
| void *res; |
| |
| /* Set heapsize to some meaningful value */ |
| if (maxheapsize == -1) |
| set_maxheapsize(ALIGN_UP(USER_ADDRESS_SPACE_SIZE_ARCH >> 1, PAGE_SIZE)); |
| |
| if (!last_allocated) |
| last_allocated = (void *) ALIGN_UP((void *) &_heap + maxheapsize, PAGE_SIZE); |
| |
| sz = ALIGN_UP(sz, PAGE_SIZE); |
| res = last_allocated; |
| last_allocated += sz; |
| |
| return res; |
| } |
| |
| /** @} |
| */ |