From mboxrd@z Thu Jan 1 00:00:00 1970 From: Izik Eidus Subject: [PATCH 3/3] add support for change_pte mmu notifiers Date: Thu, 10 Sep 2009 19:38:58 +0300 Message-ID: <1252600738-9456-4-git-send-email-ieidus@redhat.com> References: <1252600738-9456-1-git-send-email-ieidus@redhat.com> <1252600738-9456-2-git-send-email-ieidus@redhat.com> <1252600738-9456-3-git-send-email-ieidus@redhat.com> Cc: kvm@vger.kernel.org, aarcange@redhat.com, Izik Eidus To: avi@redhat.com Return-path: Received: from mx1.redhat.com ([209.132.183.28]:19002 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752782AbZIJQbA (ORCPT ); Thu, 10 Sep 2009 12:31:00 -0400 Received: from int-mx05.intmail.prod.int.phx2.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.18]) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id n8AGV407025198 for ; Thu, 10 Sep 2009 12:31:04 -0400 In-Reply-To: <1252600738-9456-3-git-send-email-ieidus@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: this is needed for kvm if it want ksm to directly map pages into its shadow page tables. Signed-off-by: Izik Eidus --- arch/x86/include/asm/kvm_host.h | 1 + arch/x86/kvm/mmu.c | 70 ++++++++++++++++++++++++++++++++++---- virt/kvm/kvm_main.c | 14 ++++++++ 3 files changed, 77 insertions(+), 8 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 6046e6f..594d131 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -797,6 +797,7 @@ asmlinkage void kvm_handle_fault_on_reboot(void); #define KVM_ARCH_WANT_MMU_NOTIFIER int kvm_unmap_hva(struct kvm *kvm, unsigned long hva); int kvm_age_hva(struct kvm *kvm, unsigned long hva); +void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte); int cpuid_maxphyaddr(struct kvm_vcpu *vcpu); int kvm_cpu_has_interrupt(struct kvm_vcpu *vcpu); int kvm_arch_interrupt_allowed(struct kvm_vcpu *vcpu); diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index a7151b8..3fd19f2 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -282,6 +282,11 @@ static pfn_t spte_to_pfn(u64 pte) return (pte & PT64_BASE_ADDR_MASK) >> PAGE_SHIFT; } +static pte_t ptep_val(pte_t *ptep) +{ + return *ptep; +} + static gfn_t pse36_gfn_delta(u32 gpte) { int shift = 32 - PT32_DIR_PSE36_SHIFT - PAGE_SHIFT; @@ -748,7 +753,8 @@ static int rmap_write_protect(struct kvm *kvm, u64 gfn) return write_protected; } -static int kvm_unmap_rmapp(struct kvm *kvm, unsigned long *rmapp) +static int kvm_unmap_rmapp(struct kvm *kvm, unsigned long *rmapp, + unsigned long data) { u64 *spte; int need_tlb_flush = 0; @@ -763,8 +769,48 @@ static int kvm_unmap_rmapp(struct kvm *kvm, unsigned long *rmapp) return need_tlb_flush; } +static int kvm_set_pte_rmapp(struct kvm *kvm, unsigned long *rmapp, + unsigned long data) +{ + int need_flush = 0; + u64 *spte, new_spte; + pte_t *ptep = (pte_t *)data; + pfn_t new_pfn; + + new_pfn = pte_pfn(ptep_val(ptep)); + spte = rmap_next(kvm, rmapp, NULL); + while (spte) { + BUG_ON(!is_shadow_present_pte(*spte)); + rmap_printk("kvm_set_pte_rmapp: spte %p %llx\n", spte, *spte); + need_flush = 1; + if (pte_write(ptep_val(ptep))) { + rmap_remove(kvm, spte); + __set_spte(spte, shadow_trap_nonpresent_pte); + spte = rmap_next(kvm, rmapp, NULL); + } else { + new_spte = *spte &~ (PT64_BASE_ADDR_MASK); + new_spte |= new_pfn << PAGE_SHIFT; + + if (!pte_write(ptep_val(ptep))) { + new_spte &= ~PT_WRITABLE_MASK; + new_spte &= ~SPTE_HOST_WRITEABLE; + if (is_writeble_pte(*spte)) + kvm_set_pfn_dirty(spte_to_pfn(*spte)); + } + __set_spte(spte, new_spte); + spte = rmap_next(kvm, rmapp, spte); + } + } + if (need_flush) + kvm_flush_remote_tlbs(kvm); + + return 0; +} + static int kvm_handle_hva(struct kvm *kvm, unsigned long hva, - int (*handler)(struct kvm *kvm, unsigned long *rmapp)) + unsigned long data, + int (*handler)(struct kvm *kvm, unsigned long *rmapp, + unsigned long data)) { int i, j; int retval = 0; @@ -786,13 +832,15 @@ static int kvm_handle_hva(struct kvm *kvm, unsigned long hva, if (hva >= start && hva < end) { gfn_t gfn_offset = (hva - start) >> PAGE_SHIFT; - retval |= handler(kvm, &memslot->rmap[gfn_offset]); + retval |= handler(kvm, &memslot->rmap[gfn_offset], + data); for (j = 0; j < KVM_NR_PAGE_SIZES - 1; ++j) { int idx = gfn_offset; idx /= KVM_PAGES_PER_HPAGE(PT_DIRECTORY_LEVEL + j); retval |= handler(kvm, - &memslot->lpage_info[j][idx].rmap_pde); + &memslot->lpage_info[j][idx].rmap_pde, + data); } } } @@ -802,10 +850,16 @@ static int kvm_handle_hva(struct kvm *kvm, unsigned long hva, int kvm_unmap_hva(struct kvm *kvm, unsigned long hva) { - return kvm_handle_hva(kvm, hva, kvm_unmap_rmapp); + return kvm_handle_hva(kvm, hva, 0, kvm_unmap_rmapp); +} + +void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte) +{ + kvm_handle_hva(kvm, hva, (unsigned long)&pte, kvm_set_pte_rmapp); } -static int kvm_age_rmapp(struct kvm *kvm, unsigned long *rmapp) +static int kvm_age_rmapp(struct kvm *kvm, unsigned long *rmapp, + unsigned long data) { u64 *spte; int young = 0; @@ -841,13 +895,13 @@ static void rmap_recycle(struct kvm_vcpu *vcpu, u64 *spte, gfn_t gfn) gfn = unalias_gfn(vcpu->kvm, gfn); rmapp = gfn_to_rmap(vcpu->kvm, gfn, sp->role.level); - kvm_unmap_rmapp(vcpu->kvm, rmapp); + kvm_unmap_rmapp(vcpu->kvm, rmapp, 0); kvm_flush_remote_tlbs(vcpu->kvm); } int kvm_age_hva(struct kvm *kvm, unsigned long hva) { - return kvm_handle_hva(kvm, hva, kvm_age_rmapp); + return kvm_handle_hva(kvm, hva, 0, kvm_age_rmapp); } #ifdef MMU_DEBUG diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index cb7966f..c9a88af 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -240,6 +240,19 @@ static void kvm_mmu_notifier_invalidate_page(struct mmu_notifier *mn, } +static void kvm_mmu_notifier_change_pte(struct mmu_notifier *mn, + struct mm_struct *mm, + unsigned long address, + pte_t pte) +{ + struct kvm *kvm = mmu_notifier_to_kvm(mn); + + spin_lock(&kvm->mmu_lock); + kvm->mmu_notifier_seq++; + kvm_set_spte_hva(kvm, address, pte); + spin_unlock(&kvm->mmu_lock); +} + static void kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn, struct mm_struct *mm, unsigned long start, @@ -319,6 +332,7 @@ static const struct mmu_notifier_ops kvm_mmu_notifier_ops = { .invalidate_range_start = kvm_mmu_notifier_invalidate_range_start, .invalidate_range_end = kvm_mmu_notifier_invalidate_range_end, .clear_flush_young = kvm_mmu_notifier_clear_flush_young, + .change_pte = kvm_mmu_notifier_change_pte, .release = kvm_mmu_notifier_release, }; #endif /* CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER */ -- 1.5.6.5