ENTRY(_start)

/*****************************************************************************
 * Virtual and linear start addresses of the TeachOS kernel
 *****************************************************************************/
TEACHOS_PMA = 1M;
TEACHOS_VMA = 0xFFFFFFFF80000000;

PHDRS {
  boot_rodata PT_LOAD FLAGS(4);
  boot_text   PT_LOAD FLAGS(5);
  boot_data   PT_LOAD FLAGS(6);

  text   PT_LOAD FLAGS(5);
  data   PT_LOAD FLAGS(6);
  rodata PT_LOAD FLAGS(4);
}

SECTIONS
{
  /***************************************************************************
   * Load the bootstrap code into low memory. We need to be accessible in
   * 32-Bit mode, so we want to live down low, but we need to leave the 1MiB
   * hole open since some BIOS functionality resides below it.
   ***************************************************************************/
  . = TEACHOS_PMA;

  /***************************************************************************
   * We want to be able to be able to access all memory (physical and virtual)
   * during bootstrapping and operation. To achieve this, we define some
   * symbols at the beginning.
   ***************************************************************************/
  _start_physical = .;
  _start_virtual = . + TEACHOS_VMA;


  /***************************************************************************
   * The bootstrapping infratructure goes first. We first place the read-only
   * data, followed by our code, initialized mutable data, and finally our 
   * uninitialized mutable data.
   ***************************************************************************/
  .boot_rodata ALIGN(4K) : AT(ADDR (.boot_rodata))
  {
    KEEP(*(.boot_mbh))
    *(.boot_rodata)
  } :boot_rodata

  .boot_text ALIGN(4K) : AT(ADDR (.boot_text))
  {
    *(.boot_text)
  } :boot_text

  .boot_bss ALIGN(4K) : AT(ADDR (.boot_bss))
  {
    *(.boot_bss)
    *(.boot_stack)
  }

  .boot_data ALIGN(4K) : AT(ADDR (.boot_data))
  {
    *(.boot_data)
  } :boot_data

  /***************************************************************************
   * Now it is time to load the 64-bit kernel code. We
   * make sure to align the loaded data onto a page boundary.
   ***************************************************************************/
  . = ALIGN(4K);
  . += TEACHOS_VMA;

  .stl_text ALIGN(4K) : AT(ADDR (.stl_text) - TEACHOS_VMA)
  {
    *(.stl_text .stl_text*)
    KEEP(*libstdc++.a:*(.text .text.*))
  } :text

  .text ALIGN(4K) : AT(ADDR (.text) - TEACHOS_VMA)
  {
    *(.text .text.*)
  }

  .user_text ALIGN(4K) : AT(ADDR (.user_text) - TEACHOS_VMA)
  {
    *(.user_text .user_text.*)
  }

  .rodata ALIGN(4K) : AT (ADDR (.rodata) - TEACHOS_VMA)
  {
    *(.rodata)
    *(.rodata.*)
  } :rodata

  .ctors ALIGN(4K) : AT (ADDR (.ctors) - TEACHOS_VMA)
  {
    __ctors_start = .;
    KEEP(*(SORT(.ctors.*)))
    KEEP(*(.ctors))
    __ctors_end = .;
  } :data

  .init_array ALIGN(4K) : AT (ADDR (.init_array) - TEACHOS_VMA)
  {
    __init_array_start = .;
    KEEP(*(SORT_BY_INIT_PRIORITY(.init_array.*)))
    KEEP(*(.init_array))
    __init_array_end = .;
  }

  .bss ALIGN(4K) : AT (ADDR (.bss) - TEACHOS_VMA)
  {
    *(COMMON)
    *(.bss*)
  }

  .data ALIGN(4K) : AT (ADDR (.data) - TEACHOS_VMA)
  {
    *(.data*)
  }

  .user_data ALIGN(4K) : AT (ADDR (.user_data) - TEACHOS_VMA)
  {
    *(.user_data .user_data.*)
  }

  /***************************************************************************
   * In accordance with the symbol definitions at the start, we generate some
   * symbols to mark the end of our loaded image.
   ***************************************************************************/
  _end_virtual = .;
  _end_physical = _end_virtual - TEACHOS_VMA;

  /DISCARD/ : { *(.comment) }
}