arch/x86/xen/enlighten_hvm.c

   1 #include <linux/cpu.h>
   2 #include <linux/kexec.h>
   3
   4 #include <xen/features.h>
   5 #include <xen/events.h>
   6 #include <xen/interface/memory.h>
   7
   8 #include <asm/cpu.h>
   9 #include <asm/smp.h>
  10 #include <asm/reboot.h>
  11 #include <asm/setup.h>
  12 #include <asm/hypervisor.h>
  13
  14 #include <asm/xen/cpuid.h>
  15 #include <asm/xen/hypervisor.h>
  16
  17 #include "xen-ops.h"
  18 #include "mmu.h"
  19 #include "smp.h"
  20
  21 void __ref xen_hvm_init_shared_info(void)
  22 {
  23         int cpu;
  24         struct xen_add_to_physmap xatp;
  25         static struct shared_info *shared_info_page;
  26
  27         if (!shared_info_page)
  28                 shared_info_page = (struct shared_info *)
  29                         extend_brk(PAGE_SIZE, PAGE_SIZE);
  30         xatp.domid = DOMID_SELF;
  31         xatp.idx = 0;
  32         xatp.space = XENMAPSPACE_shared_info;
  33         xatp.gpfn = __pa(shared_info_page) >> PAGE_SHIFT;
  34         if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp))
  35                 BUG();
  36
  37         HYPERVISOR_shared_info = (struct shared_info *)shared_info_page;
  38
  39         /* xen_vcpu is a pointer to the vcpu_info struct in the shared_info
  40          * page, we use it in the event channel upcall and in some pvclock
  41          * related functions. We don't need the vcpu_info placement
  42          * optimizations because we don't use any pv_mmu or pv_irq op on
  43          * HVM.
  44          * When xen_hvm_init_shared_info is run at boot time only vcpu 0 is
  45          * online but xen_hvm_init_shared_info is run at resume time too and
  46          * in that case multiple vcpus might be online. */
  47         for_each_online_cpu(cpu) {
  48                 xen_vcpu_info_reset(cpu);
  49         }
  50 }
  51
  52 static void __init init_hvm_pv_info(void)
  53 {
  54         int major, minor;
  55         uint32_t eax, ebx, ecx, edx, base;
  56
  57         base = xen_cpuid_base();
  58         eax = cpuid_eax(base + 1);
  59
  60         major = eax >> 16;
  61         minor = eax & 0xffff;
  62         printk(KERN_INFO "Xen version %d.%d.\n", major, minor);
  63
  64         xen_domain_type = XEN_HVM_DOMAIN;
  65
  66         /* PVH set up hypercall page in xen_prepare_pvh(). */
  67         if (xen_pvh_domain())
  68                 pv_info.name = "Xen PVH";
  69         else {
  70                 u64 pfn;
  71                 uint32_t msr;
  72
  73                 pv_info.name = "Xen HVM";
  74                 msr = cpuid_ebx(base + 2);
  75                 pfn = __pa(hypercall_page);
  76                 wrmsr_safe(msr, (u32)pfn, (u32)(pfn >> 32));
  77         }
  78
  79         xen_setup_features();
  80
  81         cpuid(base + 4, &eax, &ebx, &ecx, &edx);
  82         if (eax & XEN_HVM_CPUID_VCPU_ID_PRESENT)
  83                 this_cpu_write(xen_vcpu_id, ebx);
  84         else
  85                 this_cpu_write(xen_vcpu_id, smp_processor_id());
  86 }
  87
  88 #ifdef CONFIG_KEXEC_CORE
  89 static void xen_hvm_shutdown(void)
  90 {
  91         native_machine_shutdown();
  92         if (kexec_in_progress)
  93                 xen_reboot(SHUTDOWN_soft_reset);
  94 }
  95
  96 static void xen_hvm_crash_shutdown(struct pt_regs *regs)
  97 {
  98         native_machine_crash_shutdown(regs);
  99         xen_reboot(SHUTDOWN_soft_reset);
 100 }
 101 #endif
 102
 103 static int xen_cpu_up_prepare_hvm(unsigned int cpu)
 104 {
 105         int rc;
 106
 107         /*
 108          * This can happen if CPU was offlined earlier and
 109          * offlining timed out in common_cpu_die().
 110          */
 111         if (cpu_report_state(cpu) == CPU_DEAD_FROZEN) {
 112                 xen_smp_intr_free(cpu);
 113                 xen_uninit_lock_cpu(cpu);
 114         }
 115
 116         if (cpu_acpi_id(cpu) != U32_MAX)
 117                 per_cpu(xen_vcpu_id, cpu) = cpu_acpi_id(cpu);
 118         else
 119                 per_cpu(xen_vcpu_id, cpu) = cpu;
 120         xen_vcpu_setup(cpu);
 121
 122         if (xen_have_vector_callback && xen_feature(XENFEAT_hvm_safe_pvclock))
 123                 xen_setup_timer(cpu);
 124
 125         rc = xen_smp_intr_init(cpu);
 126         if (rc) {
 127                 WARN(1, "xen_smp_intr_init() for CPU %d failed: %d\n",
 128                      cpu, rc);
 129                 return rc;
 130         }
 131         return 0;
 132 }
 133
 134 static int xen_cpu_dead_hvm(unsigned int cpu)
 135 {
 136         xen_smp_intr_free(cpu);
 137
 138         if (xen_have_vector_callback && xen_feature(XENFEAT_hvm_safe_pvclock))
 139                 xen_teardown_timer(cpu);
 140
 141        return 0;
 142 }
 143
 144 static void __init xen_hvm_guest_init(void)
 145 {
 146         if (xen_pv_domain())
 147                 return;
 148
 149         init_hvm_pv_info();
 150
 151         xen_hvm_init_shared_info();
 152
 153         xen_panic_handler_init();
 154
 155         if (xen_feature(XENFEAT_hvm_callback_vector))
 156                 xen_have_vector_callback = 1;
 157
 158         xen_hvm_smp_init();
 159         WARN_ON(xen_cpuhp_setup(xen_cpu_up_prepare_hvm, xen_cpu_dead_hvm));
 160         xen_unplug_emulated_devices();
 161         x86_init.irqs.intr_init = xen_init_IRQ;
 162         xen_hvm_init_time_ops();
 163         xen_hvm_init_mmu_ops();
 164
 165         if (xen_pvh_domain())
 166                 machine_ops.emergency_restart = xen_emergency_restart;
 167 #ifdef CONFIG_KEXEC_CORE
 168         machine_ops.shutdown = xen_hvm_shutdown;
 169         machine_ops.crash_shutdown = xen_hvm_crash_shutdown;
 170 #endif
 171 }
 172
 173 static bool xen_nopv;
 174 static __init int xen_parse_nopv(char *arg)
 175 {
 176        xen_nopv = true;
 177        return 0;
 178 }
 179 early_param("xen_nopv", xen_parse_nopv);
 180
 181 bool xen_hvm_need_lapic(void)
 182 {
 183         if (xen_nopv)
 184                 return false;
 185         if (xen_pv_domain())
 186                 return false;
 187         if (!xen_hvm_domain())
 188                 return false;
 189         if (xen_feature(XENFEAT_hvm_pirqs) && xen_have_vector_callback)
 190                 return false;
 191         return true;
 192 }
 193 EXPORT_SYMBOL_GPL(xen_hvm_need_lapic);
 194
 195 static uint32_t __init xen_platform_hvm(void)
 196 {
 197         if (xen_pv_domain() || xen_nopv)
 198                 return 0;
 199
 200         return xen_cpuid_base();
 201 }
 202
 203 const struct hypervisor_x86 x86_hyper_xen_hvm = {
 204         .name                   = "Xen HVM",
 205         .detect                 = xen_platform_hvm,
 206         .init_platform          = xen_hvm_guest_init,
 207         .pin_vcpu               = xen_pin_vcpu,
 208         .x2apic_available       = xen_x2apic_para_available,
 209 };
 210 EXPORT_SYMBOL(x86_hyper_xen_hvm);