init.c 3.3 KB

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  1. /*
  2. * linux/arch/h8300/mm/init.c
  3. *
  4. * Copyright (C) 1998 D. Jeff Dionne <jeff@lineo.ca>,
  5. * Kenneth Albanowski <kjahds@kjahds.com>,
  6. * Copyright (C) 2000 Lineo, Inc. (www.lineo.com)
  7. *
  8. * Based on:
  9. *
  10. * linux/arch/m68knommu/mm/init.c
  11. * linux/arch/m68k/mm/init.c
  12. *
  13. * Copyright (C) 1995 Hamish Macdonald
  14. *
  15. * JAN/1999 -- hacked to support ColdFire (gerg@snapgear.com)
  16. * DEC/2000 -- linux 2.4 support <davidm@snapgear.com>
  17. */
  18. #include <linux/signal.h>
  19. #include <linux/sched.h>
  20. #include <linux/kernel.h>
  21. #include <linux/errno.h>
  22. #include <linux/string.h>
  23. #include <linux/types.h>
  24. #include <linux/ptrace.h>
  25. #include <linux/mman.h>
  26. #include <linux/mm.h>
  27. #include <linux/swap.h>
  28. #include <linux/init.h>
  29. #include <linux/highmem.h>
  30. #include <linux/pagemap.h>
  31. #include <linux/bootmem.h>
  32. #include <linux/gfp.h>
  33. #include <asm/setup.h>
  34. #include <asm/segment.h>
  35. #include <asm/page.h>
  36. #include <asm/pgtable.h>
  37. #include <asm/sections.h>
  38. /*
  39. * BAD_PAGE is the page that is used for page faults when linux
  40. * is out-of-memory. Older versions of linux just did a
  41. * do_exit(), but using this instead means there is less risk
  42. * for a process dying in kernel mode, possibly leaving a inode
  43. * unused etc..
  44. *
  45. * BAD_PAGETABLE is the accompanying page-table: it is initialized
  46. * to point to BAD_PAGE entries.
  47. *
  48. * ZERO_PAGE is a special page that is used for zero-initialized
  49. * data and COW.
  50. */
  51. static unsigned long empty_bad_page_table;
  52. static unsigned long empty_bad_page;
  53. unsigned long empty_zero_page;
  54. /*
  55. * paging_init() continues the virtual memory environment setup which
  56. * was begun by the code in arch/head.S.
  57. * The parameters are pointers to where to stick the starting and ending
  58. * addresses of available kernel virtual memory.
  59. */
  60. void __init paging_init(void)
  61. {
  62. /*
  63. * Make sure start_mem is page aligned, otherwise bootmem and
  64. * page_alloc get different views og the world.
  65. */
  66. unsigned long start_mem = PAGE_ALIGN(memory_start);
  67. unsigned long end_mem = memory_end & PAGE_MASK;
  68. pr_debug("start_mem is %#lx\nvirtual_end is %#lx\n",
  69. start_mem, end_mem);
  70. /*
  71. * Initialize the bad page table and bad page to point
  72. * to a couple of allocated pages.
  73. */
  74. empty_bad_page_table = (unsigned long)alloc_bootmem_pages(PAGE_SIZE);
  75. empty_bad_page = (unsigned long)alloc_bootmem_pages(PAGE_SIZE);
  76. empty_zero_page = (unsigned long)alloc_bootmem_pages(PAGE_SIZE);
  77. memset((void *)empty_zero_page, 0, PAGE_SIZE);
  78. /*
  79. * Set up SFC/DFC registers (user data space).
  80. */
  81. set_fs(USER_DS);
  82. pr_debug("before free_area_init\n");
  83. pr_debug("free_area_init -> start_mem is %#lx\nvirtual_end is %#lx\n",
  84. start_mem, end_mem);
  85. {
  86. unsigned long zones_size[MAX_NR_ZONES] = {0, };
  87. zones_size[ZONE_NORMAL] = (end_mem - PAGE_OFFSET) >> PAGE_SHIFT;
  88. free_area_init(zones_size);
  89. }
  90. }
  91. void __init mem_init(void)
  92. {
  93. pr_devel("Mem_init: start=%lx, end=%lx\n", memory_start, memory_end);
  94. high_memory = (void *) (memory_end & PAGE_MASK);
  95. max_mapnr = MAP_NR(high_memory);
  96. /* this will put all low memory onto the freelists */
  97. free_all_bootmem();
  98. mem_init_print_info(NULL);
  99. }
  100. #ifdef CONFIG_BLK_DEV_INITRD
  101. void free_initrd_mem(unsigned long start, unsigned long end)
  102. {
  103. free_reserved_area((void *)start, (void *)end, -1, "initrd");
  104. }
  105. #endif
  106. void
  107. free_initmem(void)
  108. {
  109. free_initmem_default(-1);
  110. }