headers/private/system/vm_defs.h

   1 /*
   2  * Copyright 2002-2008, Axel Dörfler, axeld@pinc-software.de. All rights reserved.
   3  * Distributed under the terms of the MIT License.
   4  *
   5  * Copyright 2001-2002, Travis Geiselbrecht. All rights reserved.
   6  * Distributed under the terms of the NewOS License.
   7  */
   8 #ifndef _SYSTEM_VM_DEFS_H
   9 #define _SYSTEM_VM_DEFS_H
  10
  11 #include <OS.h>
  12
  13
  14 // additional protection flags
  15 // Note: the VM probably won't support all combinations - it will try
  16 // its best, but create_area() will fail if it has to.
  17 // Of course, the exact behaviour will be documented somewhere...
  18
  19 #define B_KERNEL_EXECUTE_AREA   0x40
  20 #define B_KERNEL_STACK_AREA             0x80
  21
  22 #define B_USER_PROTECTION \
  23         (B_READ_AREA | B_WRITE_AREA | B_EXECUTE_AREA | B_STACK_AREA)
  24 #define B_KERNEL_PROTECTION \
  25         (B_KERNEL_READ_AREA | B_KERNEL_WRITE_AREA | B_KERNEL_EXECUTE_AREA \
  26         | B_KERNEL_STACK_AREA)
  27
  28 // TODO: These aren't really a protection flags, but since the "protection"
  29 //      field is the only flag field, we currently use it for this.
  30 //      A cleaner approach would be appreciated - maybe just an official generic
  31 //      flags region in the protection field.
  32 #define B_OVERCOMMITTING_AREA   0x1000
  33 #define B_SHARED_AREA                   0x2000
  34 #define B_KERNEL_AREA                   0x4000
  35         // Usable from userland according to its protection flags, but the area
  36         // itself is not deletable, resizable, etc from userland.
  37
  38 #define B_USER_AREA_FLAGS               (B_USER_PROTECTION | B_OVERCOMMITTING_AREA)
  39 #define B_KERNEL_AREA_FLAGS \
  40         (B_KERNEL_PROTECTION | B_USER_CLONEABLE_AREA | B_SHARED_AREA)
  41
  42 // mapping argument for several internal VM functions
  43 enum {
  44         REGION_NO_PRIVATE_MAP = 0,
  45         REGION_PRIVATE_MAP
  46 };
  47
  48 enum {
  49         // TODO: these are here only temporarily - it's a private
  50         // addition to the BeOS create_area() lock flags
  51         B_ALREADY_WIRED = 7,
  52 };
  53
  54 #define MEMORY_TYPE_SHIFT               28
  55
  56
  57 #endif  /* _SYSTEM_VM_DEFS_H */