drivers/xen/features.c

   1 /******************************************************************************
   2  * features.c
   3  *
   4  * Xen feature flags.
   5  *
   6  * Copyright (c) 2006, Ian Campbell, XenSource Inc.
   7  */
   8 #include <linux/types.h>
   9 #include <linux/cache.h>
  10 #include <linux/module.h>
  11 #include <asm/xen/hypervisor.h>
  12 #include <xen/features.h>
  13
  14 u8 xen_features[XENFEAT_NR_SUBMAPS * 32] __read_mostly;
  15 EXPORT_SYMBOL_GPL(xen_features);
  16
  17 void xen_setup_features(void)
  18 {
  19         struct xen_feature_info fi;
  20         int i, j;
  21
  22         for (i = 0; i < XENFEAT_NR_SUBMAPS; i++) {
  23                 fi.submap_idx = i;
  24                 if (HYPERVISOR_xen_version(XENVER_get_features, &fi) < 0)
  25                         break;
  26                 for (j = 0; j < 32; j++)
  27                         xen_features[i * 32 + j] = !!(fi.submap & 1<<j);
  28         }
  29 }