diff options
Diffstat (limited to 'arch/x86/kernel')
| -rw-r--r-- | arch/x86/kernel/Makefile | 2 | ||||
| -rw-r--r-- | arch/x86/kernel/crash.c | 3 | ||||
| -rw-r--r-- | arch/x86/kernel/kvm.c | 248 | ||||
| -rw-r--r-- | arch/x86/kernel/kvmclock.c | 187 | ||||
| -rw-r--r-- | arch/x86/kernel/reboot.c | 13 | ||||
| -rw-r--r-- | arch/x86/kernel/setup_32.c | 6 | ||||
| -rw-r--r-- | arch/x86/kernel/setup_64.c | 7 |
7 files changed, 463 insertions, 3 deletions
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile index 90e092d0af0..fa19c381954 100644 --- a/arch/x86/kernel/Makefile +++ b/arch/x86/kernel/Makefile @@ -80,6 +80,8 @@ obj-$(CONFIG_DEBUG_RODATA_TEST) += test_rodata.o obj-$(CONFIG_DEBUG_NX_TEST) += test_nx.o obj-$(CONFIG_VMI) += vmi_32.o vmiclock_32.o +obj-$(CONFIG_KVM_GUEST) += kvm.o +obj-$(CONFIG_KVM_CLOCK) += kvmclock.o obj-$(CONFIG_PARAVIRT) += paravirt.o paravirt_patch_$(BITS).o ifdef CONFIG_INPUT_PCSPKR diff --git a/arch/x86/kernel/crash.c b/arch/x86/kernel/crash.c index 2251d0ae957..26855381790 100644 --- a/arch/x86/kernel/crash.c +++ b/arch/x86/kernel/crash.c @@ -25,6 +25,7 @@ #include <asm/hpet.h> #include <linux/kdebug.h> #include <asm/smp.h> +#include <asm/reboot.h> #include <mach_ipi.h> @@ -117,7 +118,7 @@ static void nmi_shootdown_cpus(void) } #endif -void machine_crash_shutdown(struct pt_regs *regs) +void native_machine_crash_shutdown(struct pt_regs *regs) { /* This function is only called after the system * has panicked or is otherwise in a critical state. diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c new file mode 100644 index 00000000000..8b7a3cf37d2 --- /dev/null +++ b/arch/x86/kernel/kvm.c @@ -0,0 +1,248 @@ +/* + * KVM paravirt_ops implementation + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + * + * Copyright (C) 2007, Red Hat, Inc., Ingo Molnar <mingo@redhat.com> + * Copyright IBM Corporation, 2007 + * Authors: Anthony Liguori <aliguori@us.ibm.com> + */ + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/kvm_para.h> +#include <linux/cpu.h> +#include <linux/mm.h> +#include <linux/highmem.h> +#include <linux/hardirq.h> + +#define MMU_QUEUE_SIZE 1024 + +struct kvm_para_state { + u8 mmu_queue[MMU_QUEUE_SIZE]; + int mmu_queue_len; + enum paravirt_lazy_mode mode; +}; + +static DEFINE_PER_CPU(struct kvm_para_state, para_state); + +static struct kvm_para_state *kvm_para_state(void) +{ + return &per_cpu(para_state, raw_smp_processor_id()); +} + +/* + * No need for any "IO delay" on KVM + */ +static void kvm_io_delay(void) +{ +} + +static void kvm_mmu_op(void *buffer, unsigned len) +{ + int r; + unsigned long a1, a2; + + do { + a1 = __pa(buffer); + a2 = 0; /* on i386 __pa() always returns <4G */ + r = kvm_hypercall3(KVM_HC_MMU_OP, len, a1, a2); + buffer += r; + len -= r; + } while (len); +} + +static void mmu_queue_flush(struct kvm_para_state *state) +{ + if (state->mmu_queue_len) { + kvm_mmu_op(state->mmu_queue, state->mmu_queue_len); + state->mmu_queue_len = 0; + } +} + +static void kvm_deferred_mmu_op(void *buffer, int len) +{ + struct kvm_para_state *state = kvm_para_state(); + + if (state->mode != PARAVIRT_LAZY_MMU) { + kvm_mmu_op(buffer, len); + return; + } + if (state->mmu_queue_len + len > sizeof state->mmu_queue) + mmu_queue_flush(state); + memcpy(state->mmu_queue + state->mmu_queue_len, buffer, len); + state->mmu_queue_len += len; +} + +static void kvm_mmu_write(void *dest, u64 val) +{ + __u64 pte_phys; + struct kvm_mmu_op_write_pte wpte; + +#ifdef CONFIG_HIGHPTE + struct page *page; + unsigned long dst = (unsigned long) dest; + + page = kmap_atomic_to_page(dest); + pte_phys = page_to_pfn(page); + pte_phys <<= PAGE_SHIFT; + pte_phys += (dst & ~(PAGE_MASK)); +#else + pte_phys = (unsigned long)__pa(dest); +#endif + wpte.header.op = KVM_MMU_OP_WRITE_PTE; + wpte.pte_val = val; + wpte.pte_phys = pte_phys; + + kvm_deferred_mmu_op(&wpte, sizeof wpte); +} + +/* + * We only need to hook operations that are MMU writes. We hook these so that + * we can use lazy MMU mode to batch these operations. We could probably + * improve the performance of the host code if we used some of the information + * here to simplify processing of batched writes. + */ +static void kvm_set_pte(pte_t *ptep, pte_t pte) +{ + kvm_mmu_write(ptep, pte_val(pte)); +} + +static void kvm_set_pte_at(struct mm_struct *mm, unsigned long addr, + pte_t *ptep, pte_t pte) +{ + kvm_mmu_write(ptep, pte_val(pte)); +} + +static void kvm_set_pmd(pmd_t *pmdp, pmd_t pmd) +{ + kvm_mmu_write(pmdp, pmd_val(pmd)); +} + +#if PAGETABLE_LEVELS >= 3 +#ifdef CONFIG_X86_PAE +static void kvm_set_pte_atomic(pte_t *ptep, pte_t pte) +{ + kvm_mmu_write(ptep, pte_val(pte)); +} + +static void kvm_set_pte_present(struct mm_struct *mm, unsigned long addr, + pte_t *ptep, pte_t pte) +{ + kvm_mmu_write(ptep, pte_val(pte)); +} + +static void kvm_pte_clear(struct mm_struct *mm, + unsigned long addr, pte_t *ptep) +{ + kvm_mmu_write(ptep, 0); +} + +static void kvm_pmd_clear(pmd_t *pmdp) +{ + kvm_mmu_write(pmdp, 0); +} +#endif + +static void kvm_set_pud(pud_t *pudp, pud_t pud) +{ + kvm_mmu_write(pudp, pud_val(pud)); +} + +#if PAGETABLE_LEVELS == 4 +static void kvm_set_pgd(pgd_t *pgdp, pgd_t pgd) +{ + kvm_mmu_write(pgdp, pgd_val(pgd)); +} +#endif +#endif /* PAGETABLE_LEVELS >= 3 */ + +static void kvm_flush_tlb(void) +{ + struct kvm_mmu_op_flush_tlb ftlb = { + .header.op = KVM_MMU_OP_FLUSH_TLB, + }; + + kvm_deferred_mmu_op(&ftlb, sizeof ftlb); +} + +static void kvm_release_pt(u32 pfn) +{ + struct kvm_mmu_op_release_pt rpt = { + .header.op = KVM_MMU_OP_RELEASE_PT, + .pt_phys = (u64)pfn << PAGE_SHIFT, + }; + + kvm_mmu_op(&rpt, sizeof rpt); +} + +static void kvm_enter_lazy_mmu(void) +{ + struct kvm_para_state *state = kvm_para_state(); + + paravirt_enter_lazy_mmu(); + state->mode = paravirt_get_lazy_mode(); +} + +static void kvm_leave_lazy_mmu(void) +{ + struct kvm_para_state *state = kvm_para_state(); + + mmu_queue_flush(state); + paravirt_leave_lazy(paravirt_get_lazy_mode()); + state->mode = paravirt_get_lazy_mode(); +} + +static void paravirt_ops_setup(void) +{ + pv_info.name = "KVM"; + pv_info.paravirt_enabled = 1; + + if (kvm_para_has_feature(KVM_FEATURE_NOP_IO_DELAY)) + pv_cpu_ops.io_delay = kvm_io_delay; + + if (kvm_para_has_feature(KVM_FEATURE_MMU_OP)) { + pv_mmu_ops.set_pte = kvm_set_pte; + pv_mmu_ops.set_pte_at = kvm_set_pte_at; + pv_mmu_ops.set_pmd = kvm_set_pmd; +#if PAGETABLE_LEVELS >= 3 +#ifdef CONFIG_X86_PAE + pv_mmu_ops.set_pte_atomic = kvm_set_pte_atomic; + pv_mmu_ops.set_pte_present = kvm_set_pte_present; + pv_mmu_ops.pte_clear = kvm_pte_clear; + pv_mmu_ops.pmd_clear = kvm_pmd_clear; +#endif + pv_mmu_ops.set_pud = kvm_set_pud; +#if PAGETABLE_LEVELS == 4 + pv_mmu_ops.set_pgd = kvm_set_pgd; +#endif +#endif + pv_mmu_ops.flush_tlb_user = kvm_flush_tlb; + pv_mmu_ops.release_pte = kvm_release_pt; + pv_mmu_ops.release_pmd = kvm_release_pt; + pv_mmu_ops.release_pud = kvm_release_pt; + + pv_mmu_ops.lazy_mode.enter = kvm_enter_lazy_mmu; + pv_mmu_ops.lazy_mode.leave = kvm_leave_lazy_mmu; + } +} + +void __init kvm_guest_init(void) +{ + if (!kvm_para_available()) + return; + + paravirt_ops_setup(); +} diff --git a/arch/x86/kernel/kvmclock.c b/arch/x86/kernel/kvmclock.c new file mode 100644 index 00000000000..ddee04043ae --- /dev/null +++ b/arch/x86/kernel/kvmclock.c @@ -0,0 +1,187 @@ +/* KVM paravirtual clock driver. A clocksource implementation + Copyright (C) 2008 Glauber de Oliveira Costa, Red Hat Inc. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA +*/ + +#include <linux/clocksource.h> +#include <linux/kvm_para.h> +#include <asm/arch_hooks.h> +#include <asm/msr.h> +#include <asm/apic.h> +#include <linux/percpu.h> +#include <asm/reboot.h> + +#define KVM_SCALE 22 + +static int kvmclock = 1; + +static int parse_no_kvmclock(char *arg) +{ + kvmclock = 0; + return 0; +} +early_param("no-kvmclock", parse_no_kvmclock); + +/* The hypervisor will put information about time periodically here */ +static DEFINE_PER_CPU_SHARED_ALIGNED(struct kvm_vcpu_time_info, hv_clock); +#define get_clock(cpu, field) per_cpu(hv_clock, cpu).field + +static inline u64 kvm_get_delta(u64 last_tsc) +{ + int cpu = smp_processor_id(); + u64 delta = native_read_tsc() - last_tsc; + return (delta * get_clock(cpu, tsc_to_system_mul)) >> KVM_SCALE; +} + +static struct kvm_wall_clock wall_clock; +static cycle_t kvm_clock_read(void); +/* + * The wallclock is the time of day when we booted. Since then, some time may + * have elapsed since the hypervisor wrote the data. So we try to account for + * that with system time + */ +unsigned long kvm_get_wallclock(void) +{ + u32 wc_sec, wc_nsec; + u64 delta; + struct timespec ts; + int version, nsec; + int low, high; + + low = (int)__pa(&wall_clock); + high = ((u64)__pa(&wall_clock) >> 32); + + delta = kvm_clock_read(); + + native_write_msr(MSR_KVM_WALL_CLOCK, low, high); + do { + version = wall_clock.wc_version; + rmb(); + wc_sec = wall_clock.wc_sec; + wc_nsec = wall_clock.wc_nsec; + rmb(); + } while ((wall_clock.wc_version != version) || (version & 1)); + + delta = kvm_clock_read() - delta; + delta += wc_nsec; + nsec = do_div(delta, NSEC_PER_SEC); + set_normalized_timespec(&ts, wc_sec + delta, nsec); + /* + * Of all mechanisms of time adjustment I've tested, this one + * was the champion! + */ + return ts.tv_sec + 1; +} + +int kvm_set_wallclock(unsigned long now) +{ + return 0; +} + +/* + * This is our read_clock function. The host puts an tsc timestamp each time + * it updates a new time. Without the tsc adjustment, we can have a situation + * in which a vcpu starts to run earlier (smaller system_time), but probes + * time later (compared to another vcpu), leading to backwards time + */ +static cycle_t kvm_clock_read(void) +{ + u64 last_tsc, now; + int cpu; + + preempt_disable(); + cpu = smp_processor_id(); + + last_tsc = get_clock(cpu, tsc_timestamp); + now = get_clock(cpu, system_time); + + now += kvm_get_delta(last_tsc); + preempt_enable(); + + return now; +} +static struct clocksource kvm_clock = { + .name = "kvm-clock", + .read = kvm_clock_read, + .rating = 400, + .mask = CLOCKSOURCE_MASK(64), + .mult = 1 << KVM_SCALE, + .shift = KVM_SCALE, + .flags = CLOCK_SOURCE_IS_CONTINUOUS, +}; + +static int kvm_register_clock(void) +{ + int cpu = smp_processor_id(); + int low, high; + low = (int)__pa(&per_cpu(hv_clock, cpu)) | 1; + high = ((u64)__pa(&per_cpu(hv_clock, cpu)) >> 32); + + return native_write_msr_safe(MSR_KVM_SYSTEM_TIME, low, high); +} + +static void kvm_setup_secondary_clock(void) +{ + /* + * Now that the first cpu already had this clocksource initialized, + * we shouldn't fail. + */ + WARN_ON(kvm_register_clock()); + /* ok, done with our trickery, call native */ + setup_secondary_APIC_clock(); +} + +/* + * After the clock is registered, the host will keep writing to the + * registered memory location. If the guest happens to shutdown, this memory + * won't be valid. In cases like kexec, in which you install a new kernel, this + * means a random memory location will be kept being written. So before any + * kind of shutdown from our side, we unregister the clock by writting anything + * that does not have the 'enable' bit set in the msr + */ +#ifdef CONFIG_KEXEC +static void kvm_crash_shutdown(struct pt_regs *regs) +{ + native_write_msr_safe(MSR_KVM_SYSTEM_TIME, 0, 0); + native_machine_crash_shutdown(regs); +} +#endif + +static void kvm_shutdown(void) +{ + native_write_msr_safe(MSR_KVM_SYSTEM_TIME, 0, 0); + native_machine_shutdown(); +} + +void __init kvmclock_init(void) +{ + if (!kvm_para_available()) + return; + + if (kvmclock && kvm_para_has_feature(KVM_FEATURE_CLOCKSOURCE)) { + if (kvm_register_clock()) + return; + pv_time_ops.get_wallclock = kvm_get_wallclock; + pv_time_ops.set_wallclock = kvm_set_wallclock; + pv_time_ops.sched_clock = kvm_clock_read; + pv_apic_ops.setup_secondary_clock = kvm_setup_secondary_clock; + machine_ops.shutdown = kvm_shutdown; +#ifdef CONFIG_KEXEC + machine_ops.crash_shutdown = kvm_crash_shutdown; +#endif + clocksource_register(&kvm_clock); + } +} diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c index 1791a751a77..a4a838306b2 100644 --- a/arch/x86/kernel/reboot.c +++ b/arch/x86/kernel/reboot.c @@ -399,7 +399,7 @@ static void native_machine_emergency_restart(void) } } -static void native_machine_shutdown(void) +void native_machine_shutdown(void) { /* Stop the cpus and apics */ #ifdef CONFIG_SMP @@ -470,7 +470,10 @@ struct machine_ops machine_ops = { .shutdown = native_machine_shutdown, .emergency_restart = native_machine_emergency_restart, .restart = native_machine_restart, - .halt = native_machine_halt + .halt = native_machine_halt, +#ifdef CONFIG_KEXEC + .crash_shutdown = native_machine_crash_shutdown, +#endif }; void machine_power_off(void) @@ -498,3 +501,9 @@ void machine_halt(void) machine_ops.halt(); } +#ifdef CONFIG_KEXEC +void machine_crash_shutdown(struct pt_regs *regs) +{ + machine_ops.crash_shutdown(regs); +} +#endif diff --git a/arch/x86/kernel/setup_32.c b/arch/x86/kernel/setup_32.c index 44cc9b93393..2283422af79 100644 --- a/arch/x86/kernel/setup_32.c +++ b/arch/x86/kernel/setup_32.c @@ -47,6 +47,7 @@ #include <linux/pfn.h> #include <linux/pci.h> #include <linux/init_ohci1394_dma.h> +#include <linux/kvm_para.h> #include <video/edid.h> @@ -820,6 +821,10 @@ void __init setup_arch(char **cmdline_p) max_low_pfn = setup_memory(); +#ifdef CONFIG_KVM_CLOCK + kvmclock_init(); +#endif + #ifdef CONFIG_VMI /* * Must be after max_low_pfn is determined, and before kernel @@ -827,6 +832,7 @@ void __init setup_arch(char **cmdline_p) */ vmi_init(); #endif + kvm_guest_init(); /* * NOTE: before this point _nobody_ is allowed to allocate diff --git a/arch/x86/kernel/setup_64.c b/arch/x86/kernel/setup_64.c index 60e64c8eee9..a94fb959a87 100644 --- a/arch/x86/kernel/setup_64.c +++ b/arch/x86/kernel/setup_64.c @@ -42,6 +42,7 @@ #include <linux/ctype.h> #include <linux/uaccess.h> #include <linux/init_ohci1394_dma.h> +#include <linux/kvm_para.h> #include <asm/mtrr.h> #include <asm/uaccess.h> @@ -384,6 +385,10 @@ void __init setup_arch(char **cmdline_p) io_delay_init(); +#ifdef CONFIG_KVM_CLOCK + kvmclock_init(); +#endif + #ifdef CONFIG_SMP /* setup to use the early static init tables during kernel startup */ x86_cpu_to_apicid_early_ptr = (void *)x86_cpu_to_apicid_init; @@ -488,6 +493,8 @@ void __init setup_arch(char **cmdline_p) init_apic_mappings(); ioapic_init_mappings(); + kvm_guest_init(); + /* * We trust e820 completely. No explicit ROM probing in memory. */ |