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  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.
  27.  */
  28.  
  29. /** @addtogroup libc
  30.  * @{
  31.  */
  32. /** @file
  33.  */
  34.  
  35. #include <as.h>
  36. #include <libc.h>
  37. #include <unistd.h>
  38. #include <align.h>
  39. #include <sys/types.h>
  40. #include <bitops.h>
  41. #include <malloc.h>
  42.  
  43. /** Last position allocated by as_get_mappable_page */
  44. static uintptr_t last_allocated = 0;
  45.  
  46. /** Create address space area.
  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.  *
  54.  */
  55. void *as_area_create(void *address, size_t size, int flags)
  56. {
  57.     return (void *) __SYSCALL3(SYS_AS_AREA_CREATE, (sysarg_t) address,
  58.         (sysarg_t) size, (sysarg_t) flags);
  59. }
  60.  
  61. /** Resize address space area.
  62.  *
  63.  * @param address Virtual address pointing into already existing address space
  64.  *                area.
  65.  * @param size    New requested size of the area.
  66.  * @param flags   Currently unused.
  67.  *
  68.  * @return zero on success or a code from @ref errno.h on failure.
  69.  *
  70.  */
  71. int as_area_resize(void *address, size_t size, int flags)
  72. {
  73.     return __SYSCALL3(SYS_AS_AREA_RESIZE, (sysarg_t) address,
  74.         (sysarg_t) size, (sysarg_t) flags);
  75. }
  76.  
  77. /** Destroy address space area.
  78.  *
  79.  * @param address Virtual address pointing into the address space area being
  80.  *                destroyed.
  81.  *
  82.  * @return zero on success or a code from @ref errno.h on failure.
  83.  *
  84.  */
  85. int as_area_destroy(void *address)
  86. {
  87.     return __SYSCALL1(SYS_AS_AREA_DESTROY, (sysarg_t) address);
  88. }
  89.  
  90. /** Change address-space area flags.
  91.  *
  92.  * @param address Virtual address pointing into the address space area being
  93.  *                modified.
  94.  * @param flags   New flags describing type of the area.
  95.  *
  96.  * @return zero on success or a code from @ref errno.h on failure.
  97.  *
  98.  */
  99. int as_area_change_flags(void *address, int flags)
  100. {
  101.     return __SYSCALL2(SYS_AS_AREA_CHANGE_FLAGS, (sysarg_t) address,
  102.         (sysarg_t) flags);
  103. }
  104.  
  105. /** Return pointer to some unmapped area, where fits new as_area
  106.  *
  107.  * @param size Requested size of the allocation.
  108.  *
  109.  * @return pointer to the beginning
  110.  *
  111.  */
  112. void *as_get_mappable_page(size_t size)
  113. {
  114.     if (size == 0)
  115.         return NULL;
  116.    
  117.     size_t sz = 1 << (fnzb(size - 1) + 1);
  118.     if (last_allocated == 0)
  119.         last_allocated = get_max_heap_addr();
  120.    
  121.     /*
  122.      * Make sure we allocate from naturally aligned address.
  123.      */
  124.     uintptr_t res = ALIGN_UP(last_allocated, sz);
  125.     last_allocated = res + ALIGN_UP(size, PAGE_SIZE);
  126.    
  127.     return ((void *) res);
  128. }
  129.  
  130. /** @}
  131.  */
  132.