include/xen/interface/features.h

   1 /******************************************************************************
   2  * features.h
   3  *
   4  * Feature flags, reported by XENVER_get_features.
   5  *
   6  * Copyright (c) 2006, Keir Fraser <keir@xensource.com>
   7  */
   8
   9 #ifndef __XEN_PUBLIC_FEATURES_H__
  10 #define __XEN_PUBLIC_FEATURES_H__
  11
  12 /*
  13  * If set, the guest does not need to write-protect its pagetables, and can
  14  * update them via direct writes.
  15  */
  16 #define XENFEAT_writable_page_tables       0
  17
  18 /*
  19  * If set, the guest does not need to write-protect its segment descriptor
  20  * tables, and can update them via direct writes.
  21  */
  22 #define XENFEAT_writable_descriptor_tables 1
  23
  24 /*
  25  * If set, translation between the guest's 'pseudo-physical' address space
  26  * and the host's machine address space are handled by the hypervisor. In this
  27  * mode the guest does not need to perform phys-to/from-machine translations
  28  * when performing page table operations.
  29  */
  30 #define XENFEAT_auto_translated_physmap    2
  31
  32 /* If set, the guest is running in supervisor mode (e.g., x86 ring 0). */
  33 #define XENFEAT_supervisor_mode_kernel     3
  34
  35 /*
  36  * If set, the guest does not need to allocate x86 PAE page directories
  37  * below 4GB. This flag is usually implied by auto_translated_physmap.
  38  */
  39 #define XENFEAT_pae_pgdir_above_4gb        4
  40
  41 /* x86: Does this Xen host support the MMU_PT_UPDATE_PRESERVE_AD hypercall? */
  42 #define XENFEAT_mmu_pt_update_preserve_ad  5
  43
  44 #define XENFEAT_NR_SUBMAPS 1
  45
  46 #endif /* __XEN_PUBLIC_FEATURES_H__ */