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/page.h>
  20 #include <xen/interface/callback.h>
  21 #include <xen/interface/physdev.h>
  22 #include <xen/features.h>
  23
  24 #include "xen-ops.h"
  25 #include "vdso.h"
  26
  27 /* These are code, but not functions.  Defined in entry.S */
  28 extern const char xen_hypervisor_callback[];
  29 extern const char xen_failsafe_callback[];
  30
  31
  32 /**
  33  * machine_specific_memory_setup - Hook for machine specific memory setup.
  34  **/
  35
  36 char * __init xen_memory_setup(void)
  37 {
  38         unsigned long max_pfn = xen_start_info->nr_pages;
  39
  40         max_pfn = min(MAX_DOMAIN_PAGES, max_pfn);
  41
  42         e820.nr_map = 0;
  43         add_memory_region(0, LOWMEMSIZE(), E820_RAM);
  44         add_memory_region(HIGH_MEMORY, PFN_PHYS(max_pfn)-HIGH_MEMORY, E820_RAM);
  45
  46         return "Xen";
  47 }
  48
  49 static void xen_idle(void)
  50 {
  51         local_irq_disable();
  52
  53         if (need_resched())
  54                 local_irq_enable();
  55         else {
  56                 current_thread_info()->status &= ~TS_POLLING;
  57                 smp_mb__after_clear_bit();
  58                 safe_halt();
  59                 current_thread_info()->status |= TS_POLLING;
  60         }
  61 }
  62
  63 /*
  64  * Set the bit indicating "nosegneg" library variants should be used.
  65  */
  66 static void __init fiddle_vdso(void)
  67 {
  68         extern const char vdso32_default_start;
  69         u32 *mask = VDSO32_SYMBOL(&vdso32_default_start, NOTE_MASK);
  70         *mask |= 1 << VDSO_NOTE_NONEGSEG_BIT;
  71 }
  72
  73 void xen_enable_sysenter(void)
  74 {
  75         int cpu = smp_processor_id();
  76         extern void xen_sysenter_target(void);
  77         /* Mask events on entry, even though they get enabled immediately */
  78         static struct callback_register sysenter = {
  79                 .type = CALLBACKTYPE_sysenter,
  80                 .address = { __KERNEL_CS, (unsigned long)xen_sysenter_target },
  81                 .flags = CALLBACKF_mask_events,
  82         };
  83
  84         if (!boot_cpu_has(X86_FEATURE_SEP) ||
  85             HYPERVISOR_callback_op(CALLBACKOP_register, &sysenter) != 0) {
  86                 clear_cpu_cap(&cpu_data(cpu), X86_FEATURE_SEP);
  87                 clear_cpu_cap(&boot_cpu_data, X86_FEATURE_SEP);
  88         }
  89 }
  90
  91 void __init xen_arch_setup(void)
  92 {
  93         struct physdev_set_iopl set_iopl;
  94         int rc;
  95
  96         HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_4gb_segments);
  97         HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_writable_pagetables);
  98
  99         if (!xen_feature(XENFEAT_auto_translated_physmap))
 100                 HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_pae_extended_cr3);
 101
 102         HYPERVISOR_set_callbacks(__KERNEL_CS, (unsigned long)xen_hypervisor_callback,
 103                                  __KERNEL_CS, (unsigned long)xen_failsafe_callback);
 104
 105         xen_enable_sysenter();
 106
 107         set_iopl.iopl = 1;
 108         rc = HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl, &set_iopl);
 109         if (rc != 0)
 110                 printk(KERN_INFO "physdev_op failed %d\n", rc);
 111
 112 #ifdef CONFIG_ACPI
 113         if (!(xen_start_info->flags & SIF_INITDOMAIN)) {
 114                 printk(KERN_INFO "ACPI in unprivileged domain disabled\n");
 115                 disable_acpi();
 116         }
 117 #endif
 118
 119         memcpy(boot_command_line, xen_start_info->cmd_line,
 120                MAX_GUEST_CMDLINE > COMMAND_LINE_SIZE ?
 121                COMMAND_LINE_SIZE : MAX_GUEST_CMDLINE);
 122
 123         pm_idle = xen_idle;
 124
 125 #ifdef CONFIG_SMP
 126         /* fill cpus_possible with all available cpus */
 127         xen_fill_possible_map();
 128 #endif
 129
 130         paravirt_disable_iospace();
 131
 132         fiddle_vdso();
 133 }