xen: reserve Xen-specific memory in e820 map
[linux-3.10.git] / 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
44         e820_add_region(0, LOWMEMSIZE(), E820_RAM);
45         e820_add_region(HIGH_MEMORY, PFN_PHYS(max_pfn)-HIGH_MEMORY, E820_RAM);
46
47         /*
48          * Reserve Xen bits:
49          *  - mfn_list
50          *  - xen_start_info
51          * See comment above "struct start_info" in <xen/interface/xen.h>
52          */
53         e820_add_region(__pa(xen_start_info->mfn_list),
54                         xen_start_info->pt_base - xen_start_info->mfn_list,
55                         E820_RESERVED);
56
57         sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
58
59         return "Xen";
60 }
61
62 static void xen_idle(void)
63 {
64         local_irq_disable();
65
66         if (need_resched())
67                 local_irq_enable();
68         else {
69                 current_thread_info()->status &= ~TS_POLLING;
70                 smp_mb__after_clear_bit();
71                 safe_halt();
72                 current_thread_info()->status |= TS_POLLING;
73         }
74 }
75
76 /*
77  * Set the bit indicating "nosegneg" library variants should be used.
78  */
79 static void __init fiddle_vdso(void)
80 {
81         extern const char vdso32_default_start;
82         u32 *mask = VDSO32_SYMBOL(&vdso32_default_start, NOTE_MASK);
83         *mask |= 1 << VDSO_NOTE_NONEGSEG_BIT;
84 }
85
86 void xen_enable_sysenter(void)
87 {
88         int cpu = smp_processor_id();
89         extern void xen_sysenter_target(void);
90         /* Mask events on entry, even though they get enabled immediately */
91         static struct callback_register sysenter = {
92                 .type = CALLBACKTYPE_sysenter,
93                 .address = { __KERNEL_CS, (unsigned long)xen_sysenter_target },
94                 .flags = CALLBACKF_mask_events,
95         };
96
97         if (!boot_cpu_has(X86_FEATURE_SEP) ||
98             HYPERVISOR_callback_op(CALLBACKOP_register, &sysenter) != 0) {
99                 clear_cpu_cap(&cpu_data(cpu), X86_FEATURE_SEP);
100                 clear_cpu_cap(&boot_cpu_data, X86_FEATURE_SEP);
101         }
102 }
103
104 void __init xen_arch_setup(void)
105 {
106         struct physdev_set_iopl set_iopl;
107         int rc;
108
109         HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_4gb_segments);
110         HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_writable_pagetables);
111
112         if (!xen_feature(XENFEAT_auto_translated_physmap))
113                 HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_pae_extended_cr3);
114
115         HYPERVISOR_set_callbacks(__KERNEL_CS, (unsigned long)xen_hypervisor_callback,
116                                  __KERNEL_CS, (unsigned long)xen_failsafe_callback);
117
118         xen_enable_sysenter();
119
120         set_iopl.iopl = 1;
121         rc = HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl, &set_iopl);
122         if (rc != 0)
123                 printk(KERN_INFO "physdev_op failed %d\n", rc);
124
125 #ifdef CONFIG_ACPI
126         if (!(xen_start_info->flags & SIF_INITDOMAIN)) {
127                 printk(KERN_INFO "ACPI in unprivileged domain disabled\n");
128                 disable_acpi();
129         }
130 #endif
131
132         memcpy(boot_command_line, xen_start_info->cmd_line,
133                MAX_GUEST_CMDLINE > COMMAND_LINE_SIZE ?
134                COMMAND_LINE_SIZE : MAX_GUEST_CMDLINE);
135
136         pm_idle = xen_idle;
137
138 #ifdef CONFIG_SMP
139         /* fill cpus_possible with all available cpus */
140         xen_fill_possible_map();
141 #endif
142
143         paravirt_disable_iospace();
144
145         fiddle_vdso();
146 }