From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752287AbZKAL4k (ORCPT ); Sun, 1 Nov 2009 06:56:40 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752256AbZKAL4g (ORCPT ); Sun, 1 Nov 2009 06:56:36 -0500 Received: from mx1.redhat.com ([209.132.183.28]:12589 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752032AbZKAL42 (ORCPT ); Sun, 1 Nov 2009 06:56:28 -0500 From: Gleb Natapov To: kvm@vger.kernel.org Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH 01/11] Add shared memory hypercall to PV Linux guest. Date: Sun, 1 Nov 2009 13:56:20 +0200 Message-Id: <1257076590-29559-2-git-send-email-gleb@redhat.com> In-Reply-To: <1257076590-29559-1-git-send-email-gleb@redhat.com> References: <1257076590-29559-1-git-send-email-gleb@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add hypercall that allows guest and host to setup per cpu shared memory. Signed-off-by: Gleb Natapov --- arch/x86/include/asm/kvm_host.h | 3 + arch/x86/include/asm/kvm_para.h | 11 +++++ arch/x86/kernel/kvm.c | 82 +++++++++++++++++++++++++++++++++++++++ arch/x86/kernel/setup.c | 1 + arch/x86/kernel/smpboot.c | 3 + arch/x86/kvm/x86.c | 70 +++++++++++++++++++++++++++++++++ include/linux/kvm.h | 1 + include/linux/kvm_para.h | 4 ++ 8 files changed, 175 insertions(+), 0 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 26a74b7..2d1f526 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -374,6 +374,9 @@ struct kvm_vcpu_arch { /* used for guest single stepping over the given code position */ u16 singlestep_cs; unsigned long singlestep_rip; + + struct kvm_vcpu_pv_shm *pv_shm; + struct page *pv_shm_page; }; struct kvm_mem_alias { diff --git a/arch/x86/include/asm/kvm_para.h b/arch/x86/include/asm/kvm_para.h index c584076..90708b7 100644 --- a/arch/x86/include/asm/kvm_para.h +++ b/arch/x86/include/asm/kvm_para.h @@ -15,6 +15,7 @@ #define KVM_FEATURE_CLOCKSOURCE 0 #define KVM_FEATURE_NOP_IO_DELAY 1 #define KVM_FEATURE_MMU_OP 2 +#define KVM_FEATURE_ASYNC_PF 3 #define MSR_KVM_WALL_CLOCK 0x11 #define MSR_KVM_SYSTEM_TIME 0x12 @@ -47,6 +48,16 @@ struct kvm_mmu_op_release_pt { __u64 pt_phys; }; +#define KVM_PV_SHM_VERSION 1 + +#define KVM_PV_SHM_FEATURES_ASYNC_PF (1 << 0) + +struct kvm_vcpu_pv_shm { + __u64 features; + __u64 reason; + __u64 param; +}; + #ifdef __KERNEL__ #include diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index 63b0ec8..d03f33c 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -27,7 +27,11 @@ #include #include #include +#include +#include +#include #include +#include #define MMU_QUEUE_SIZE 1024 @@ -37,6 +41,7 @@ struct kvm_para_state { }; static DEFINE_PER_CPU(struct kvm_para_state, para_state); +static DEFINE_PER_CPU(struct kvm_vcpu_pv_shm *, kvm_vcpu_pv_shm); static struct kvm_para_state *kvm_para_state(void) { @@ -50,6 +55,17 @@ static void kvm_io_delay(void) { } +static void kvm_end_context_switch(struct task_struct *next) +{ + struct kvm_vcpu_pv_shm *pv_shm = + per_cpu(kvm_vcpu_pv_shm, smp_processor_id()); + + if (!pv_shm) + return; + + pv_shm->current_task = (u64)next; +} + static void kvm_mmu_op(void *buffer, unsigned len) { int r; @@ -231,10 +247,76 @@ static void __init paravirt_ops_setup(void) #endif } +static void kvm_pv_unregister_shm(void *unused) +{ + if (per_cpu(kvm_vcpu_pv_shm, smp_processor_id()) == NULL) + return; + + kvm_hypercall3(KVM_HC_SETUP_SHM, 0, 0, KVM_PV_SHM_VERSION); + printk(KERN_INFO"Unregister pv shared memory for cpu %d\n", + smp_processor_id()); + +} + +static int kvm_pv_reboot_notify(struct notifier_block *nb, + unsigned long code, void *unused) +{ + if (code == SYS_RESTART) + on_each_cpu(kvm_pv_unregister_shm, NULL, 1); + return NOTIFY_DONE; +} + +static struct notifier_block kvm_pv_reboot_nb = { + .notifier_call = kvm_pv_reboot_notify, +}; + void __init kvm_guest_init(void) { if (!kvm_para_available()) return; paravirt_ops_setup(); + register_reboot_notifier(&kvm_pv_reboot_nb); +} + +void __cpuinit kvm_guest_cpu_init(void) +{ + int r; + unsigned long a0, a1, a2; + struct kvm_vcpu_pv_shm *pv_shm; + + if (!kvm_para_available()) + return; + + if (smp_processor_id() == boot_cpu_id) + pv_shm = alloc_bootmem(sizeof(*pv_shm)); + else + pv_shm = kmalloc(sizeof(*pv_shm), GFP_ATOMIC); + + if (!pv_shm) + return; + + memset(pv_shm, 0, sizeof(*pv_shm)); + + if (kvm_para_has_feature(KVM_FEATURE_ASYNC_PF)) + pv_shm->features |= KVM_PV_SHM_FEATURES_ASYNC_PF; + + per_cpu(kvm_vcpu_pv_shm, smp_processor_id()) = pv_shm; + a0 = __pa(pv_shm); + a1 = sizeof(*pv_shm); + a2 = KVM_PV_SHM_VERSION; + r = kvm_hypercall3(KVM_HC_SETUP_SHM, a0, a1, a2); + + if (!r) { + printk(KERN_INFO"Setup pv shared memory for cpu %d\n", + smp_processor_id()); + return; + } + + if (smp_processor_id() == boot_cpu_id) + free_bootmem(__pa(pv_shm), sizeof(*pv_shm)); + else + kfree(pv_shm); + + per_cpu(kvm_vcpu_pv_shm, smp_processor_id()) = NULL; } diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index e09f0e2..1c2f8dd 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -1007,6 +1007,7 @@ void __init setup_arch(char **cmdline_p) probe_nr_irqs_gsi(); kvm_guest_init(); + kvm_guest_cpu_init(); e820_reserve_resources(); e820_mark_nosave_regions(max_low_pfn); diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index 565ebc6..5599098 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -65,6 +65,7 @@ #include #include #include +#include #include @@ -321,6 +322,8 @@ notrace static void __cpuinit start_secondary(void *unused) ipi_call_unlock(); per_cpu(cpu_state, smp_processor_id()) = CPU_ONLINE; + kvm_guest_cpu_init(); + /* enable local interrupts */ local_irq_enable(); diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 2ef3906..c177933 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -1342,6 +1342,7 @@ int kvm_dev_ioctl_check_extension(long ext) case KVM_CAP_SET_IDENTITY_MAP_ADDR: case KVM_CAP_XEN_HVM: case KVM_CAP_ADJUST_CLOCK: + case KVM_CAP_ASYNC_PF: r = 1; break; case KVM_CAP_COALESCED_MMIO: @@ -3371,6 +3372,68 @@ int kvm_emulate_halt(struct kvm_vcpu *vcpu) } EXPORT_SYMBOL_GPL(kvm_emulate_halt); +static void kvm_pv_release_shm(struct kvm_vcpu *vcpu) +{ + if (!vcpu->arch.pv_shm_page) + return; + + kunmap(vcpu->arch.pv_shm_page); + put_page(vcpu->arch.pv_shm_page); + vcpu->arch.pv_shm_page = NULL; + vcpu->arch.pv_shm = NULL; +} + +static int kvm_pv_setup_shm(struct kvm_vcpu *vcpu, unsigned long gpa, + unsigned long size, unsigned long version, + unsigned long *ret) +{ + int r; + unsigned long addr; + gfn_t gfn = gpa >> PAGE_SHIFT; + int offset = offset_in_page(gpa); + struct mm_struct *mm = current->mm; + void *p; + + *ret = -KVM_EINVAL; + + if (size == 0 && vcpu->arch.pv_shm != NULL && + version == KVM_PV_SHM_VERSION) { + kvm_pv_release_shm(vcpu); + goto out; + } + + if (vcpu->arch.pv_shm != NULL || size != sizeof(*vcpu->arch.pv_shm) || + size > PAGE_SIZE || version != KVM_PV_SHM_VERSION) + return -EINVAL; + + *ret = -KVM_EFAULT; + + addr = gfn_to_hva(vcpu->kvm, gfn); + if (kvm_is_error_hva(addr)) + return -EFAULT; + + /* pin page with pv shared memory */ + down_read(&mm->mmap_sem); + r = get_user_pages(current, mm, addr, 1, 1, 0, &vcpu->arch.pv_shm_page, + NULL); + up_read(&mm->mmap_sem); + if (r != 1) + return -EFAULT; + + p = kmap(vcpu->arch.pv_shm_page); + if (!p) { + put_page(vcpu->arch.pv_shm_page); + vcpu->arch.pv_shm_page = NULL; + return -ENOMEM; + } + + vcpu->arch.pv_shm = p + offset; + +out: + *ret = 0; + return 0; +} + static inline gpa_t hc_gpa(struct kvm_vcpu *vcpu, unsigned long a0, unsigned long a1) { @@ -3413,6 +3476,9 @@ int kvm_emulate_hypercall(struct kvm_vcpu *vcpu) case KVM_HC_MMU_OP: r = kvm_pv_mmu_op(vcpu, a0, hc_gpa(vcpu, a1, a2), &ret); break; + case KVM_HC_SETUP_SHM: + r = kvm_pv_setup_shm(vcpu, a0, a1, a2, &ret); + break; default: ret = -KVM_ENOSYS; break; @@ -4860,6 +4926,8 @@ free_vcpu: void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu) { + kvm_pv_release_shm(vcpu); + vcpu_load(vcpu); kvm_mmu_unload(vcpu); vcpu_put(vcpu); @@ -4877,6 +4945,8 @@ int kvm_arch_vcpu_reset(struct kvm_vcpu *vcpu) vcpu->arch.dr6 = DR6_FIXED_1; vcpu->arch.dr7 = DR7_FIXED_1; + kvm_pv_release_shm(vcpu); + return kvm_x86_ops->vcpu_reset(vcpu); } diff --git a/include/linux/kvm.h b/include/linux/kvm.h index 6ed1a12..2fec4a2 100644 --- a/include/linux/kvm.h +++ b/include/linux/kvm.h @@ -440,6 +440,7 @@ struct kvm_ioeventfd { #define KVM_CAP_XEN_HVM 38 #endif #define KVM_CAP_ADJUST_CLOCK 39 +#define KVM_CAP_ASYNC_PF 40 #ifdef KVM_CAP_IRQ_ROUTING diff --git a/include/linux/kvm_para.h b/include/linux/kvm_para.h index d731092..1c37495 100644 --- a/include/linux/kvm_para.h +++ b/include/linux/kvm_para.h @@ -14,9 +14,11 @@ #define KVM_EFAULT EFAULT #define KVM_E2BIG E2BIG #define KVM_EPERM EPERM +#define KVM_EINVAL EINVAL #define KVM_HC_VAPIC_POLL_IRQ 1 #define KVM_HC_MMU_OP 2 +#define KVM_HC_SETUP_SHM 3 /* * hypercalls use architecture specific @@ -26,8 +28,10 @@ #ifdef __KERNEL__ #ifdef CONFIG_KVM_GUEST void __init kvm_guest_init(void); +void __cpuinit kvm_guest_cpu_init(void); #else #define kvm_guest_init() do { } while (0) +#define kvm_guest_cpu_init() do { } while (0) #endif static inline int kvm_para_has_feature(unsigned int feature) -- 1.6.3.3