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/vdso.h>
  14 #include <asm/e820.h>
  15 #include <asm/setup.h>
  16 #include <asm/xen/hypervisor.h>
  17 #include <asm/xen/hypercall.h>
  18
  19 #include <xen/interface/callback.h>
  20 #include <xen/interface/physdev.h>
  21 #include <xen/features.h>
  22
  23 #include "xen-ops.h"
  24 #include "vdso.h"
  25
  26 /* These are code, but not functions.  Defined in entry.S */
  27 extern const char xen_hypervisor_callback[];
  28 extern const char xen_failsafe_callback[];
  29
  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, LOWMEMSIZE(), E820_RAM);
  41         add_memory_region(HIGH_MEMORY, PFN_PHYS(max_pfn)-HIGH_MEMORY, E820_RAM);
  42
  43         return "Xen";
  44 }
  45
  46 static void xen_idle(void)
  47 {
  48         local_irq_disable();
  49
  50         if (need_resched())
  51                 local_irq_enable();
  52         else {
  53                 current_thread_info()->status &= ~TS_POLLING;
  54                 smp_mb__after_clear_bit();
  55                 safe_halt();
  56                 current_thread_info()->status |= TS_POLLING;
  57         }
  58 }
  59
  60 /*
  61  * Set the bit indicating "nosegneg" library variants should be used.
  62  */
  63 static void __init fiddle_vdso(void)
  64 {
  65         extern const char vdso32_default_start;
  66         u32 *mask = VDSO32_SYMBOL(&vdso32_default_start, NOTE_MASK);
  67         *mask |= 1 << VDSO_NOTE_NONEGSEG_BIT;
  68 }
  69
  70 void xen_enable_sysenter(void)
  71 {
  72         int cpu = smp_processor_id();
  73         extern void xen_sysenter_target(void);
  74         /* Mask events on entry, even though they get enabled immediately */
  75         static struct callback_register sysenter = {
  76                 .type = CALLBACKTYPE_sysenter,
  77                 .address = { __KERNEL_CS, (unsigned long)xen_sysenter_target },
  78                 .flags = CALLBACKF_mask_events,
  79         };
  80
  81         if (!boot_cpu_has(X86_FEATURE_SEP) ||
  82             HYPERVISOR_callback_op(CALLBACKOP_register, &sysenter) != 0) {
  83                 clear_cpu_cap(&cpu_data(cpu), X86_FEATURE_SEP);
  84                 clear_cpu_cap(&boot_cpu_data, X86_FEATURE_SEP);
  85         }
  86 }
  87
  88 void __init xen_arch_setup(void)
  89 {
  90         struct physdev_set_iopl set_iopl;
  91         int rc;
  92
  93         HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_4gb_segments);
  94         HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_writable_pagetables);
  95
  96         if (!xen_feature(XENFEAT_auto_translated_physmap))
  97                 HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_pae_extended_cr3);
  98
  99         HYPERVISOR_set_callbacks(__KERNEL_CS, (unsigned long)xen_hypervisor_callback,
 100                                  __KERNEL_CS, (unsigned long)xen_failsafe_callback);
 101
 102         xen_enable_sysenter();
 103
 104         set_iopl.iopl = 1;
 105         rc = HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl, &set_iopl);
 106         if (rc != 0)
 107                 printk(KERN_INFO "physdev_op failed %d\n", rc);
 108
 109 #ifdef CONFIG_ACPI
 110         if (!(xen_start_info->flags & SIF_INITDOMAIN)) {
 111                 printk(KERN_INFO "ACPI in unprivileged domain disabled\n");
 112                 disable_acpi();
 113         }
 114 #endif
 115
 116         memcpy(boot_command_line, xen_start_info->cmd_line,
 117                MAX_GUEST_CMDLINE > COMMAND_LINE_SIZE ?
 118                COMMAND_LINE_SIZE : MAX_GUEST_CMDLINE);
 119
 120         pm_idle = xen_idle;
 121
 122 #ifdef CONFIG_SMP
 123         /* fill cpus_possible with all available cpus */
 124         xen_fill_possible_map();
 125 #endif
 126
 127         paravirt_disable_iospace();
 128
 129         fiddle_vdso();
 130 }