diff options
Diffstat (limited to 'arch/x86/kernel/kvmclock.c')
| -rw-r--r-- | arch/x86/kernel/kvmclock.c | 50 |
1 files changed, 24 insertions, 26 deletions
diff --git a/arch/x86/kernel/kvmclock.c b/arch/x86/kernel/kvmclock.c index ad273e5861c1..ca0a49eeac4a 100644 --- a/arch/x86/kernel/kvmclock.c +++ b/arch/x86/kernel/kvmclock.c @@ -16,16 +16,16 @@ #include <linux/mm.h> #include <linux/slab.h> #include <linux/set_memory.h> +#include <linux/cc_platform.h> #include <asm/hypervisor.h> -#include <asm/mem_encrypt.h> #include <asm/x86_init.h> #include <asm/kvmclock.h> static int kvmclock __initdata = 1; static int kvmclock_vsyscall __initdata = 1; -static int msr_kvm_system_time __ro_after_init = MSR_KVM_SYSTEM_TIME; -static int msr_kvm_wall_clock __ro_after_init = MSR_KVM_WALL_CLOCK; +static int msr_kvm_system_time __ro_after_init; +static int msr_kvm_wall_clock __ro_after_init; static u64 kvm_sched_clock_offset __ro_after_init; static int __init parse_no_kvmclock(char *arg) @@ -42,25 +42,16 @@ static int __init parse_no_kvmclock_vsyscall(char *arg) } early_param("no-kvmclock-vsyscall", parse_no_kvmclock_vsyscall); -/* Aligned to page sizes to match whats mapped via vsyscalls to userspace */ +/* Aligned to page sizes to match what's mapped via vsyscalls to userspace */ #define HVC_BOOT_ARRAY_SIZE \ (PAGE_SIZE / sizeof(struct pvclock_vsyscall_time_info)) static struct pvclock_vsyscall_time_info hv_clock_boot[HVC_BOOT_ARRAY_SIZE] __bss_decrypted __aligned(PAGE_SIZE); static struct pvclock_wall_clock wall_clock __bss_decrypted; -static DEFINE_PER_CPU(struct pvclock_vsyscall_time_info *, hv_clock_per_cpu); static struct pvclock_vsyscall_time_info *hvclock_mem; - -static inline struct pvclock_vcpu_time_info *this_cpu_pvti(void) -{ - return &this_cpu_read(hv_clock_per_cpu)->pvti; -} - -static inline struct pvclock_vsyscall_time_info *this_cpu_hvclock(void) -{ - return this_cpu_read(hv_clock_per_cpu); -} +DEFINE_PER_CPU(struct pvclock_vsyscall_time_info *, hv_clock_per_cpu); +EXPORT_PER_CPU_SYMBOL_GPL(hv_clock_per_cpu); /* * The wallclock is the time of day when we booted. Since then, some time may @@ -69,7 +60,7 @@ static inline struct pvclock_vsyscall_time_info *this_cpu_hvclock(void) */ static void kvm_get_wallclock(struct timespec64 *now) { - wrmsrl(msr_kvm_wall_clock, slow_virt_to_phys(&wall_clock)); + wrmsrq(msr_kvm_wall_clock, slow_virt_to_phys(&wall_clock)); preempt_disable(); pvclock_read_wallclock(&wall_clock, this_cpu_pvti(), now); preempt_enable(); @@ -85,7 +76,7 @@ static u64 kvm_clock_read(void) u64 ret; preempt_disable_notrace(); - ret = pvclock_clocksource_read(this_cpu_pvti()); + ret = pvclock_clocksource_read_nowd(this_cpu_pvti()); preempt_enable_notrace(); return ret; } @@ -95,9 +86,9 @@ static u64 kvm_clock_get_cycles(struct clocksource *cs) return kvm_clock_read(); } -static u64 kvm_sched_clock_read(void) +static noinstr u64 kvm_sched_clock_read(void) { - return kvm_clock_read() - kvm_sched_clock_offset; + return pvclock_clocksource_read_nowd(this_cpu_pvti()) - kvm_sched_clock_offset; } static inline void kvm_sched_clock_init(bool stable) @@ -163,15 +154,15 @@ static int kvm_cs_enable(struct clocksource *cs) return 0; } -struct clocksource kvm_clock = { +static struct clocksource kvm_clock = { .name = "kvm-clock", .read = kvm_clock_get_cycles, .rating = 400, .mask = CLOCKSOURCE_MASK(64), .flags = CLOCK_SOURCE_IS_CONTINUOUS, + .id = CSID_X86_KVM_CLK, .enable = kvm_cs_enable, }; -EXPORT_SYMBOL_GPL(kvm_clock); static void kvm_register_clock(char *txt) { @@ -182,8 +173,8 @@ static void kvm_register_clock(char *txt) return; pa = slow_virt_to_phys(&src->pvti) | 0x01ULL; - wrmsrl(msr_kvm_system_time, pa); - pr_info("kvm-clock: cpu %d, msr %llx, %s", smp_processor_id(), pa, txt); + wrmsrq(msr_kvm_system_time, pa); + pr_debug("kvm-clock: cpu %d, msr %llx, %s", smp_processor_id(), pa, txt); } static void kvm_save_sched_clock_state(void) @@ -204,7 +195,8 @@ static void kvm_setup_secondary_clock(void) void kvmclock_disable(void) { - native_write_msr(msr_kvm_system_time, 0, 0); + if (msr_kvm_system_time) + native_write_msr(msr_kvm_system_time, 0); } static void __init kvmclock_init_mem(void) @@ -232,7 +224,7 @@ static void __init kvmclock_init_mem(void) * hvclock is shared between the guest and the hypervisor, must * be mapped decrypted. */ - if (sev_active()) { + if (cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT)) { r = set_memory_decrypted((unsigned long) hvclock_mem, 1UL << order); if (r) { @@ -248,6 +240,9 @@ static void __init kvmclock_init_mem(void) static int __init kvm_setup_vsyscall_timeinfo(void) { + if (!kvm_para_available() || !kvmclock || nopv) + return 0; + kvmclock_init_mem(); #ifdef CONFIG_X86_64 @@ -300,7 +295,10 @@ void __init kvmclock_init(void) if (kvm_para_has_feature(KVM_FEATURE_CLOCKSOURCE2)) { msr_kvm_system_time = MSR_KVM_SYSTEM_TIME_NEW; msr_kvm_wall_clock = MSR_KVM_WALL_CLOCK_NEW; - } else if (!kvm_para_has_feature(KVM_FEATURE_CLOCKSOURCE)) { + } else if (kvm_para_has_feature(KVM_FEATURE_CLOCKSOURCE)) { + msr_kvm_system_time = MSR_KVM_SYSTEM_TIME; + msr_kvm_wall_clock = MSR_KVM_WALL_CLOCK; + } else { return; } |