arch/x86/xen/setup.c

   1 /*
   2  * Machine specific setup for xen
   3  *
   4  * Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007
   5  */
   6
   7 #include <linux/module.h>
   8 #include <linux/sched.h>
   9 #include <linux/mm.h>
  10 #include <linux/pm.h>
  11
  12 #include <asm/elf.h>
  13 #include <asm/e820.h>
  14 #include <asm/setup.h>
  15 #include <asm/xen/hypervisor.h>
  16 #include <asm/xen/hypercall.h>
  17
  18 #include <xen/interface/physdev.h>
  19 #include <xen/features.h>
  20
  21 #include "xen-ops.h"
  22 #include "vdso.h"
  23
  24 /* These are code, but not functions.  Defined in entry.S */
  25 extern const char xen_hypervisor_callback[];
  26 extern const char xen_failsafe_callback[];
  27
  28 unsigned long *phys_to_machine_mapping;
  29 EXPORT_SYMBOL(phys_to_machine_mapping);
  30
  31 /**
  32  * machine_specific_memory_setup - Hook for machine specific memory setup.
  33  **/
  34
  35 char * __init xen_memory_setup(void)
  36 {
  37         unsigned long max_pfn = xen_start_info->nr_pages;
  38
  39         e820.nr_map = 0;
  40         add_memory_region(0, PFN_PHYS(max_pfn), E820_RAM);
  41
  42         return "Xen";
  43 }
  44
  45 static void xen_idle(void)
  46 {
  47         local_irq_disable();
  48
  49         if (need_resched())
  50                 local_irq_enable();
  51         else {
  52                 current_thread_info()->status &= ~TS_POLLING;
  53                 smp_mb__after_clear_bit();
  54                 safe_halt();
  55                 current_thread_info()->status |= TS_POLLING;
  56         }
  57 }
  58
  59 /*
  60  * Set the bit indicating "nosegneg" library variants should be used.
  61  */
  62 static void fiddle_vdso(void)
  63 {
  64         extern u32 VDSO_NOTE_MASK; /* See ../kernel/vsyscall-note.S.  */
  65         extern char vsyscall_int80_start;
  66         u32 *mask = (u32 *) ((unsigned long) &VDSO_NOTE_MASK - VDSO_PRELINK +
  67                              &vsyscall_int80_start);
  68         *mask |= 1 << VDSO_NOTE_NONEGSEG_BIT;
  69 }
  70
  71 void __init xen_arch_setup(void)
  72 {
  73         struct physdev_set_iopl set_iopl;
  74         int rc;
  75
  76         HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_4gb_segments);
  77         HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_writable_pagetables);
  78
  79         if (!xen_feature(XENFEAT_auto_translated_physmap))
  80                 HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_pae_extended_cr3);
  81
  82         HYPERVISOR_set_callbacks(__KERNEL_CS, (unsigned long)xen_hypervisor_callback,
  83                                  __KERNEL_CS, (unsigned long)xen_failsafe_callback);
  84
  85         set_iopl.iopl = 1;
  86         rc = HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl, &set_iopl);
  87         if (rc != 0)
  88                 printk(KERN_INFO "physdev_op failed %d\n", rc);
  89
  90 #ifdef CONFIG_ACPI
  91         if (!(xen_start_info->flags & SIF_INITDOMAIN)) {
  92                 printk(KERN_INFO "ACPI in unprivileged domain disabled\n");
  93                 disable_acpi();
  94         }
  95 #endif
  96
  97         memcpy(boot_command_line, xen_start_info->cmd_line,
  98                MAX_GUEST_CMDLINE > COMMAND_LINE_SIZE ?
  99                COMMAND_LINE_SIZE : MAX_GUEST_CMDLINE);
 100
 101         pm_idle = xen_idle;
 102
 103 #ifdef CONFIG_SMP
 104         /* fill cpus_possible with all available cpus */
 105         xen_fill_possible_map();
 106 #endif
 107
 108         paravirt_disable_iospace();
 109
 110         fiddle_vdso();
 111 }