x86/virt: Add enum for hypervisors to replace x86_hyper
[muen/linux.git] / arch / x86 / xen / enlighten_hvm.c
1 #include <linux/cpu.h>
2 #include <linux/kexec.h>
3 #include <linux/memblock.h>
4
5 #include <xen/features.h>
6 #include <xen/events.h>
7 #include <xen/interface/memory.h>
8
9 #include <asm/cpu.h>
10 #include <asm/smp.h>
11 #include <asm/reboot.h>
12 #include <asm/setup.h>
13 #include <asm/hypervisor.h>
14 #include <asm/e820/api.h>
15 #include <asm/early_ioremap.h>
16
17 #include <asm/xen/cpuid.h>
18 #include <asm/xen/hypervisor.h>
19 #include <asm/xen/page.h>
20
21 #include "xen-ops.h"
22 #include "mmu.h"
23 #include "smp.h"
24
25 static unsigned long shared_info_pfn;
26
27 void xen_hvm_init_shared_info(void)
28 {
29         struct xen_add_to_physmap xatp;
30
31         xatp.domid = DOMID_SELF;
32         xatp.idx = 0;
33         xatp.space = XENMAPSPACE_shared_info;
34         xatp.gpfn = shared_info_pfn;
35         if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp))
36                 BUG();
37 }
38
39 static void __init reserve_shared_info(void)
40 {
41         u64 pa;
42
43         /*
44          * Search for a free page starting at 4kB physical address.
45          * Low memory is preferred to avoid an EPT large page split up
46          * by the mapping.
47          * Starting below X86_RESERVE_LOW (usually 64kB) is fine as
48          * the BIOS used for HVM guests is well behaved and won't
49          * clobber memory other than the first 4kB.
50          */
51         for (pa = PAGE_SIZE;
52              !e820__mapped_all(pa, pa + PAGE_SIZE, E820_TYPE_RAM) ||
53              memblock_is_reserved(pa);
54              pa += PAGE_SIZE)
55                 ;
56
57         shared_info_pfn = PHYS_PFN(pa);
58
59         memblock_reserve(pa, PAGE_SIZE);
60         HYPERVISOR_shared_info = early_memremap(pa, PAGE_SIZE);
61 }
62
63 static void __init xen_hvm_init_mem_mapping(void)
64 {
65         early_memunmap(HYPERVISOR_shared_info, PAGE_SIZE);
66         HYPERVISOR_shared_info = __va(PFN_PHYS(shared_info_pfn));
67 }
68
69 static void __init init_hvm_pv_info(void)
70 {
71         int major, minor;
72         uint32_t eax, ebx, ecx, edx, base;
73
74         base = xen_cpuid_base();
75         eax = cpuid_eax(base + 1);
76
77         major = eax >> 16;
78         minor = eax & 0xffff;
79         printk(KERN_INFO "Xen version %d.%d.\n", major, minor);
80
81         xen_domain_type = XEN_HVM_DOMAIN;
82
83         /* PVH set up hypercall page in xen_prepare_pvh(). */
84         if (xen_pvh_domain())
85                 pv_info.name = "Xen PVH";
86         else {
87                 u64 pfn;
88                 uint32_t msr;
89
90                 pv_info.name = "Xen HVM";
91                 msr = cpuid_ebx(base + 2);
92                 pfn = __pa(hypercall_page);
93                 wrmsr_safe(msr, (u32)pfn, (u32)(pfn >> 32));
94         }
95
96         xen_setup_features();
97
98         cpuid(base + 4, &eax, &ebx, &ecx, &edx);
99         if (eax & XEN_HVM_CPUID_VCPU_ID_PRESENT)
100                 this_cpu_write(xen_vcpu_id, ebx);
101         else
102                 this_cpu_write(xen_vcpu_id, smp_processor_id());
103 }
104
105 #ifdef CONFIG_KEXEC_CORE
106 static void xen_hvm_shutdown(void)
107 {
108         native_machine_shutdown();
109         if (kexec_in_progress)
110                 xen_reboot(SHUTDOWN_soft_reset);
111 }
112
113 static void xen_hvm_crash_shutdown(struct pt_regs *regs)
114 {
115         native_machine_crash_shutdown(regs);
116         xen_reboot(SHUTDOWN_soft_reset);
117 }
118 #endif
119
120 static int xen_cpu_up_prepare_hvm(unsigned int cpu)
121 {
122         int rc = 0;
123
124         /*
125          * This can happen if CPU was offlined earlier and
126          * offlining timed out in common_cpu_die().
127          */
128         if (cpu_report_state(cpu) == CPU_DEAD_FROZEN) {
129                 xen_smp_intr_free(cpu);
130                 xen_uninit_lock_cpu(cpu);
131         }
132
133         if (cpu_acpi_id(cpu) != U32_MAX)
134                 per_cpu(xen_vcpu_id, cpu) = cpu_acpi_id(cpu);
135         else
136                 per_cpu(xen_vcpu_id, cpu) = cpu;
137         rc = xen_vcpu_setup(cpu);
138         if (rc)
139                 return rc;
140
141         if (xen_have_vector_callback && xen_feature(XENFEAT_hvm_safe_pvclock))
142                 xen_setup_timer(cpu);
143
144         rc = xen_smp_intr_init(cpu);
145         if (rc) {
146                 WARN(1, "xen_smp_intr_init() for CPU %d failed: %d\n",
147                      cpu, rc);
148         }
149         return rc;
150 }
151
152 static int xen_cpu_dead_hvm(unsigned int cpu)
153 {
154         xen_smp_intr_free(cpu);
155
156         if (xen_have_vector_callback && xen_feature(XENFEAT_hvm_safe_pvclock))
157                 xen_teardown_timer(cpu);
158
159        return 0;
160 }
161
162 static void __init xen_hvm_guest_init(void)
163 {
164         if (xen_pv_domain())
165                 return;
166
167         init_hvm_pv_info();
168
169         reserve_shared_info();
170         xen_hvm_init_shared_info();
171
172         /*
173          * xen_vcpu is a pointer to the vcpu_info struct in the shared_info
174          * page, we use it in the event channel upcall and in some pvclock
175          * related functions.
176          */
177         xen_vcpu_info_reset(0);
178
179         xen_panic_handler_init();
180
181         if (xen_feature(XENFEAT_hvm_callback_vector))
182                 xen_have_vector_callback = 1;
183
184         xen_hvm_smp_init();
185         WARN_ON(xen_cpuhp_setup(xen_cpu_up_prepare_hvm, xen_cpu_dead_hvm));
186         xen_unplug_emulated_devices();
187         x86_init.irqs.intr_init = xen_init_IRQ;
188         xen_hvm_init_time_ops();
189         xen_hvm_init_mmu_ops();
190
191         if (xen_pvh_domain())
192                 machine_ops.emergency_restart = xen_emergency_restart;
193 #ifdef CONFIG_KEXEC_CORE
194         machine_ops.shutdown = xen_hvm_shutdown;
195         machine_ops.crash_shutdown = xen_hvm_crash_shutdown;
196 #endif
197 }
198
199 static bool xen_nopv;
200 static __init int xen_parse_nopv(char *arg)
201 {
202        xen_nopv = true;
203        return 0;
204 }
205 early_param("xen_nopv", xen_parse_nopv);
206
207 bool xen_hvm_need_lapic(void)
208 {
209         if (xen_nopv)
210                 return false;
211         if (xen_pv_domain())
212                 return false;
213         if (!xen_hvm_domain())
214                 return false;
215         if (xen_feature(XENFEAT_hvm_pirqs) && xen_have_vector_callback)
216                 return false;
217         return true;
218 }
219 EXPORT_SYMBOL_GPL(xen_hvm_need_lapic);
220
221 static uint32_t __init xen_platform_hvm(void)
222 {
223         if (xen_pv_domain() || xen_nopv)
224                 return 0;
225
226         return xen_cpuid_base();
227 }
228
229 const __initconst struct hypervisor_x86 x86_hyper_xen_hvm = {
230         .name                   = "Xen HVM",
231         .detect                 = xen_platform_hvm,
232         .type                   = X86_HYPER_XEN_HVM,
233         .init.init_platform     = xen_hvm_guest_init,
234         .init.x2apic_available  = xen_x2apic_para_available,
235         .init.init_mem_mapping  = xen_hvm_init_mem_mapping,
236         .runtime.pin_vcpu       = xen_pin_vcpu,
237 };