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 unsigned long *phys_to_machine_mapping;
  31 EXPORT_SYMBOL(phys_to_machine_mapping);
  32
  33 /**
  34  * machine_specific_memory_setup - Hook for machine specific memory setup.
  35  **/
  36
  37 char * __init xen_memory_setup(void)
  38 {
  39         unsigned long max_pfn = xen_start_info->nr_pages;
  40
  41         e820.nr_map = 0;
  42         add_memory_region(0, LOWMEMSIZE(), E820_RAM);
  43         add_memory_region(HIGH_MEMORY, PFN_PHYS(max_pfn)-HIGH_MEMORY, E820_RAM);
  44
  45         return "Xen";
  46 }
  47
  48 static void xen_idle(void)
  49 {
  50         local_irq_disable();
  51
  52         if (need_resched())
  53                 local_irq_enable();
  54         else {
  55                 current_thread_info()->status &= ~TS_POLLING;
  56                 smp_mb__after_clear_bit();
  57                 safe_halt();
  58                 current_thread_info()->status |= TS_POLLING;
  59         }
  60 }
  61
  62 /*
  63  * Set the bit indicating "nosegneg" library variants should be used.
  64  */
  65 static void __init fiddle_vdso(void)
  66 {
  67         extern const char vdso32_default_start;
  68         u32 *mask = VDSO32_SYMBOL(&vdso32_default_start, NOTE_MASK);
  69         *mask |= 1 << VDSO_NOTE_NONEGSEG_BIT;
  70 }
  71
  72 void xen_enable_sysenter(void)
  73 {
  74         int cpu = smp_processor_id();
  75         extern void xen_sysenter_target(void);
  76         /* Mask events on entry, even though they get enabled immediately */
  77         static struct callback_register sysenter = {
  78                 .type = CALLBACKTYPE_sysenter,
  79                 .address = { __KERNEL_CS, (unsigned long)xen_sysenter_target },
  80                 .flags = CALLBACKF_mask_events,
  81         };
  82
  83         if (!boot_cpu_has(X86_FEATURE_SEP) ||
  84             HYPERVISOR_callback_op(CALLBACKOP_register, &sysenter) != 0) {
  85                 clear_cpu_cap(&cpu_data(cpu), X86_FEATURE_SEP);
  86                 clear_cpu_cap(&boot_cpu_data, X86_FEATURE_SEP);
  87         }
  88 }
  89
  90 void __init xen_arch_setup(void)
  91 {
  92         struct physdev_set_iopl set_iopl;
  93         int rc;
  94
  95         HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_4gb_segments);
  96         HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_writable_pagetables);
  97
  98         if (!xen_feature(XENFEAT_auto_translated_physmap))
  99                 HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_pae_extended_cr3);
 100
 101         HYPERVISOR_set_callbacks(__KERNEL_CS, (unsigned long)xen_hypervisor_callback,
 102                                  __KERNEL_CS, (unsigned long)xen_failsafe_callback);
 103
 104         xen_enable_sysenter();
 105
 106         set_iopl.iopl = 1;
 107         rc = HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl, &set_iopl);
 108         if (rc != 0)
 109                 printk(KERN_INFO "physdev_op failed %d\n", rc);
 110
 111 #ifdef CONFIG_ACPI
 112         if (!(xen_start_info->flags & SIF_INITDOMAIN)) {
 113                 printk(KERN_INFO "ACPI in unprivileged domain disabled\n");
 114                 disable_acpi();
 115         }
 116 #endif
 117
 118         memcpy(boot_command_line, xen_start_info->cmd_line,
 119                MAX_GUEST_CMDLINE > COMMAND_LINE_SIZE ?
 120                COMMAND_LINE_SIZE : MAX_GUEST_CMDLINE);
 121
 122         pm_idle = xen_idle;
 123
 124 #ifdef CONFIG_SMP
 125         /* fill cpus_possible with all available cpus */
 126         xen_fill_possible_map();
 127 #endif
 128
 129         paravirt_disable_iospace();
 130
 131         fiddle_vdso();
 132 }