diff options
Diffstat (limited to 'arch/x86/kernel/cpu/mshyperv.c')
| -rw-r--r-- | arch/x86/kernel/cpu/mshyperv.c | 72 |
1 files changed, 72 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c index 46668e255421..f924a76c6923 100644 --- a/arch/x86/kernel/cpu/mshyperv.c +++ b/arch/x86/kernel/cpu/mshyperv.c @@ -37,9 +37,76 @@ /* Is Linux running as the root partition? */ bool hv_root_partition; +/* Is Linux running on nested Microsoft Hypervisor */ +bool hv_nested; struct ms_hyperv_info ms_hyperv; #if IS_ENABLED(CONFIG_HYPERV) +static inline unsigned int hv_get_nested_reg(unsigned int reg) +{ + if (hv_is_sint_reg(reg)) + return reg - HV_REGISTER_SINT0 + HV_REGISTER_NESTED_SINT0; + + switch (reg) { + case HV_REGISTER_SIMP: + return HV_REGISTER_NESTED_SIMP; + case HV_REGISTER_SIEFP: + return HV_REGISTER_NESTED_SIEFP; + case HV_REGISTER_SVERSION: + return HV_REGISTER_NESTED_SVERSION; + case HV_REGISTER_SCONTROL: + return HV_REGISTER_NESTED_SCONTROL; + case HV_REGISTER_EOM: + return HV_REGISTER_NESTED_EOM; + default: + return reg; + } +} + +u64 hv_get_non_nested_register(unsigned int reg) +{ + u64 value; + + if (hv_is_synic_reg(reg) && hv_isolation_type_snp()) + hv_ghcb_msr_read(reg, &value); + else + rdmsrl(reg, value); + return value; +} +EXPORT_SYMBOL_GPL(hv_get_non_nested_register); + +void hv_set_non_nested_register(unsigned int reg, u64 value) +{ + if (hv_is_synic_reg(reg) && hv_isolation_type_snp()) { + hv_ghcb_msr_write(reg, value); + + /* Write proxy bit via wrmsl instruction */ + if (hv_is_sint_reg(reg)) + wrmsrl(reg, value | 1 << 20); + } else { + wrmsrl(reg, value); + } +} +EXPORT_SYMBOL_GPL(hv_set_non_nested_register); + +u64 hv_get_register(unsigned int reg) +{ + if (hv_nested) + reg = hv_get_nested_reg(reg); + + return hv_get_non_nested_register(reg); +} +EXPORT_SYMBOL_GPL(hv_get_register); + +void hv_set_register(unsigned int reg, u64 value) +{ + if (hv_nested) + reg = hv_get_nested_reg(reg); + + hv_set_non_nested_register(reg, value); +} +EXPORT_SYMBOL_GPL(hv_set_register); + static void (*vmbus_handler)(void); static void (*hv_stimer0_handler)(void); static void (*hv_kexec_handler)(void); @@ -301,6 +368,11 @@ static void __init ms_hyperv_init_platform(void) pr_info("Hyper-V: running as root partition\n"); } + if (ms_hyperv.hints & HV_X64_HYPERV_NESTED) { + hv_nested = true; + pr_info("Hyper-V: running on a nested hypervisor\n"); + } + /* * Extract host information. */ |