From: Paul Mackerras <paulus@samba.org> To: Alexander Graf <agraf@suse.de> Cc: kvm-ppc@vger.kernel.org, kvm@vger.kernel.org Subject: [PATCH 3/3] KVM: PPC: Book3S HV: Handle memory slot deletion and modification correctly Date: Wed, 12 Sep 2012 09:28:18 +1000 [thread overview] Message-ID: <20120911232818.GD32642@bloggs.ozlabs.ibm.com> (raw) In-Reply-To: <20120911232614.GA32642@bloggs.ozlabs.ibm.com> This adds an implementation of kvm_arch_flush_shadow_memslot for Book3S HV, and arranges for kvmppc_core_commit_memory_region to flush the dirty log when modifying an existing slot. With this, we can handle deletion and modification of memory slots. kvm_arch_flush_shadow_memslot calls kvmppc_core_flush_memslot, which on Book3S HV now traverses the reverse map chains to remove any HPT (hashed page table) entries referring to pages in the memslot. This gets called by generic code whenever deleting a memslot or changing the guest physical address for a memslot. We flush the dirty log in kvmppc_core_commit_memory_region for consistency with what x86 does. We only need to flush when an existing memslot is being modified, because for a new memslot the rmap array (which stores the dirty bits) is all zero, meaning that every page is considered clean already, and when deleting a memslot we obviously don't care about the dirty bits any more. Signed-off-by: Paul Mackerras <paulus@samba.org> --- arch/powerpc/include/asm/kvm_book3s.h | 2 +- arch/powerpc/include/asm/kvm_ppc.h | 5 ++++- arch/powerpc/kvm/book3s_64_mmu_hv.c | 33 ++++++++++++++++++++++++++++----- arch/powerpc/kvm/book3s_hv.c | 18 ++++++++++++++++-- arch/powerpc/kvm/book3s_hv_rm_mmu.c | 2 +- arch/powerpc/kvm/book3s_pr.c | 7 ++++++- arch/powerpc/kvm/booke.c | 7 ++++++- arch/powerpc/kvm/powerpc.c | 3 ++- 8 files changed, 64 insertions(+), 13 deletions(-) diff --git a/arch/powerpc/include/asm/kvm_book3s.h b/arch/powerpc/include/asm/kvm_book3s.h index f0e0c6a..ab73800 100644 --- a/arch/powerpc/include/asm/kvm_book3s.h +++ b/arch/powerpc/include/asm/kvm_book3s.h @@ -160,7 +160,7 @@ extern long kvmppc_virtmode_h_enter(struct kvm_vcpu *vcpu, unsigned long flags, extern long kvmppc_h_enter(struct kvm_vcpu *vcpu, unsigned long flags, long pte_index, unsigned long pteh, unsigned long ptel); extern long kvmppc_hv_get_dirty_log(struct kvm *kvm, - struct kvm_memory_slot *memslot); + struct kvm_memory_slot *memslot, unsigned long *map); extern void kvmppc_entry_trampoline(void); extern void kvmppc_hv_entry_trampoline(void); diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h index 1cde8a1c..4f390cb 100644 --- a/arch/powerpc/include/asm/kvm_ppc.h +++ b/arch/powerpc/include/asm/kvm_ppc.h @@ -147,9 +147,12 @@ extern int kvmppc_core_prepare_memory_region(struct kvm *kvm, struct kvm_memory_slot *memslot, struct kvm_userspace_memory_region *mem); extern void kvmppc_core_commit_memory_region(struct kvm *kvm, - struct kvm_userspace_memory_region *mem); + struct kvm_userspace_memory_region *mem, + struct kvm_memory_slot old); extern int kvm_vm_ioctl_get_smmu_info(struct kvm *kvm, struct kvm_ppc_smmu_info *info); +extern void kvmppc_core_flush_memslot(struct kvm *kvm, + struct kvm_memory_slot *memslot); extern int kvmppc_bookehv_init(void); extern void kvmppc_bookehv_exit(void); diff --git a/arch/powerpc/kvm/book3s_64_mmu_hv.c b/arch/powerpc/kvm/book3s_64_mmu_hv.c index a389cc6..f598366 100644 --- a/arch/powerpc/kvm/book3s_64_mmu_hv.c +++ b/arch/powerpc/kvm/book3s_64_mmu_hv.c @@ -851,7 +851,8 @@ static int kvm_unmap_rmapp(struct kvm *kvm, unsigned long *rmapp, psize = hpte_page_size(hptep[0], ptel); if ((hptep[0] & HPTE_V_VALID) && hpte_rpn(ptel, psize) == gfn) { - hptep[0] |= HPTE_V_ABSENT; + if (kvm->arch.using_mmu_notifiers) + hptep[0] |= HPTE_V_ABSENT; kvmppc_invalidate_hpte(kvm, hptep, i); /* Harvest R and C */ rcbits = hptep[1] & (HPTE_R_R | HPTE_R_C); @@ -878,6 +879,28 @@ int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end) return 0; } +void kvmppc_core_flush_memslot(struct kvm *kvm, struct kvm_memory_slot *memslot) +{ + unsigned long *rmapp; + unsigned long gfn; + unsigned long n; + + rmapp = memslot->arch.rmap; + gfn = memslot->base_gfn; + for (n = memslot->npages; n; --n) { + /* + * Testing the present bit without locking is OK because + * the memslot has been marked invalid already, and hence + * no new HPTEs referencing this page can be created, + * thus the present bit can't go from 0 to 1. + */ + if (*rmapp & KVMPPC_RMAP_PRESENT) + kvm_unmap_rmapp(kvm, rmapp, gfn); + ++rmapp; + ++gfn; + } +} + static int kvm_age_rmapp(struct kvm *kvm, unsigned long *rmapp, unsigned long gfn) { @@ -1031,16 +1054,16 @@ static int kvm_test_clear_dirty(struct kvm *kvm, unsigned long *rmapp) return ret; } -long kvmppc_hv_get_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot) +long kvmppc_hv_get_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot, + unsigned long *map) { unsigned long i; - unsigned long *rmapp, *map; + unsigned long *rmapp; preempt_disable(); rmapp = memslot->arch.rmap; - map = memslot->dirty_bitmap; for (i = 0; i < memslot->npages; ++i) { - if (kvm_test_clear_dirty(kvm, rmapp)) + if (kvm_test_clear_dirty(kvm, rmapp) && map) __set_bit_le(i, map); ++rmapp; } diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index 817837d..38c7f1b 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -1288,7 +1288,7 @@ int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log) n = kvm_dirty_bitmap_bytes(memslot); memset(memslot->dirty_bitmap, 0, n); - r = kvmppc_hv_get_dirty_log(kvm, memslot); + r = kvmppc_hv_get_dirty_log(kvm, memslot, memslot->dirty_bitmap); if (r) goto out; @@ -1378,8 +1378,22 @@ int kvmppc_core_prepare_memory_region(struct kvm *kvm, } void kvmppc_core_commit_memory_region(struct kvm *kvm, - struct kvm_userspace_memory_region *mem) + struct kvm_userspace_memory_region *mem, + struct kvm_memory_slot old) { + unsigned long npages = mem->memory_size >> PAGE_SHIFT; + struct kvm_memory_slot *memslot; + + if (npages && old.npages) { + /* + * If modifying a memslot, reset all the rmap dirty bits. + * If this is a new memslot, we don't need to do anything + * since the rmap array starts out as all zeroes, + * i.e. no pages are dirty. + */ + memslot = id_to_memslot(kvm->memslots, mem->slot); + kvmppc_hv_get_dirty_log(kvm, memslot, NULL); + } } static int kvmppc_hv_setup_htab_rma(struct kvm_vcpu *vcpu) diff --git a/arch/powerpc/kvm/book3s_hv_rm_mmu.c b/arch/powerpc/kvm/book3s_hv_rm_mmu.c index 63eb94e..9955216 100644 --- a/arch/powerpc/kvm/book3s_hv_rm_mmu.c +++ b/arch/powerpc/kvm/book3s_hv_rm_mmu.c @@ -81,7 +81,7 @@ static void remove_revmap_chain(struct kvm *kvm, long pte_index, ptel = rev->guest_rpte |= rcbits; gfn = hpte_rpn(ptel, hpte_page_size(hpte_v, ptel)); memslot = __gfn_to_memslot(kvm_memslots(kvm), gfn); - if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID)) + if (!memslot) return; rmap = real_vmalloc_addr(&memslot->arch.rmap[gfn - memslot->base_gfn]); diff --git a/arch/powerpc/kvm/book3s_pr.c b/arch/powerpc/kvm/book3s_pr.c index 53f65a2..016e1ed 100644 --- a/arch/powerpc/kvm/book3s_pr.c +++ b/arch/powerpc/kvm/book3s_pr.c @@ -1200,7 +1200,12 @@ int kvmppc_core_prepare_memory_region(struct kvm *kvm, } void kvmppc_core_commit_memory_region(struct kvm *kvm, - struct kvm_userspace_memory_region *mem) + struct kvm_userspace_memory_region *mem, + struct kvm_memory_slot old) +{ +} + +void kvmppc_core_flush_memslot(struct kvm *kvm, struct kvm_memory_slot *memslot) { } diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c index 0e66b46..c91f8be 100644 --- a/arch/powerpc/kvm/booke.c +++ b/arch/powerpc/kvm/booke.c @@ -1272,7 +1272,12 @@ int kvmppc_core_prepare_memory_region(struct kvm *kvm, } void kvmppc_core_commit_memory_region(struct kvm *kvm, - struct kvm_userspace_memory_region *mem) + struct kvm_userspace_memory_region *mem, + struct kvm_memory_slot old) +{ +} + +void kvmppc_core_flush_memslot(struct kvm *kvm, struct kvm_memory_slot *memslot) { } diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c index 3a29f29..229627e 100644 --- a/arch/powerpc/kvm/powerpc.c +++ b/arch/powerpc/kvm/powerpc.c @@ -324,7 +324,7 @@ void kvm_arch_commit_memory_region(struct kvm *kvm, struct kvm_memory_slot old, int user_alloc) { - kvmppc_core_commit_memory_region(kvm, mem); + kvmppc_core_commit_memory_region(kvm, mem, old); } void kvm_arch_flush_shadow_all(struct kvm *kvm) @@ -334,6 +334,7 @@ void kvm_arch_flush_shadow_all(struct kvm *kvm) void kvm_arch_flush_shadow_memslot(struct kvm *kvm, struct kvm_memory_slot *slot) { + kvmppc_core_flush_memslot(kvm, slot); } struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id) -- 1.7.10.rc3.219.g53414
WARNING: multiple messages have this Message-ID (diff)
From: Paul Mackerras <paulus@samba.org> To: Alexander Graf <agraf@suse.de> Cc: kvm-ppc@vger.kernel.org, kvm@vger.kernel.org Subject: [PATCH 3/3] KVM: PPC: Book3S HV: Handle memory slot deletion and modification correctly Date: Tue, 11 Sep 2012 23:28:18 +0000 [thread overview] Message-ID: <20120911232818.GD32642@bloggs.ozlabs.ibm.com> (raw) In-Reply-To: <20120911232614.GA32642@bloggs.ozlabs.ibm.com> This adds an implementation of kvm_arch_flush_shadow_memslot for Book3S HV, and arranges for kvmppc_core_commit_memory_region to flush the dirty log when modifying an existing slot. With this, we can handle deletion and modification of memory slots. kvm_arch_flush_shadow_memslot calls kvmppc_core_flush_memslot, which on Book3S HV now traverses the reverse map chains to remove any HPT (hashed page table) entries referring to pages in the memslot. This gets called by generic code whenever deleting a memslot or changing the guest physical address for a memslot. We flush the dirty log in kvmppc_core_commit_memory_region for consistency with what x86 does. We only need to flush when an existing memslot is being modified, because for a new memslot the rmap array (which stores the dirty bits) is all zero, meaning that every page is considered clean already, and when deleting a memslot we obviously don't care about the dirty bits any more. Signed-off-by: Paul Mackerras <paulus@samba.org> --- arch/powerpc/include/asm/kvm_book3s.h | 2 +- arch/powerpc/include/asm/kvm_ppc.h | 5 ++++- arch/powerpc/kvm/book3s_64_mmu_hv.c | 33 ++++++++++++++++++++++++++++----- arch/powerpc/kvm/book3s_hv.c | 18 ++++++++++++++++-- arch/powerpc/kvm/book3s_hv_rm_mmu.c | 2 +- arch/powerpc/kvm/book3s_pr.c | 7 ++++++- arch/powerpc/kvm/booke.c | 7 ++++++- arch/powerpc/kvm/powerpc.c | 3 ++- 8 files changed, 64 insertions(+), 13 deletions(-) diff --git a/arch/powerpc/include/asm/kvm_book3s.h b/arch/powerpc/include/asm/kvm_book3s.h index f0e0c6a..ab73800 100644 --- a/arch/powerpc/include/asm/kvm_book3s.h +++ b/arch/powerpc/include/asm/kvm_book3s.h @@ -160,7 +160,7 @@ extern long kvmppc_virtmode_h_enter(struct kvm_vcpu *vcpu, unsigned long flags, extern long kvmppc_h_enter(struct kvm_vcpu *vcpu, unsigned long flags, long pte_index, unsigned long pteh, unsigned long ptel); extern long kvmppc_hv_get_dirty_log(struct kvm *kvm, - struct kvm_memory_slot *memslot); + struct kvm_memory_slot *memslot, unsigned long *map); extern void kvmppc_entry_trampoline(void); extern void kvmppc_hv_entry_trampoline(void); diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h index 1cde8a1c..4f390cb 100644 --- a/arch/powerpc/include/asm/kvm_ppc.h +++ b/arch/powerpc/include/asm/kvm_ppc.h @@ -147,9 +147,12 @@ extern int kvmppc_core_prepare_memory_region(struct kvm *kvm, struct kvm_memory_slot *memslot, struct kvm_userspace_memory_region *mem); extern void kvmppc_core_commit_memory_region(struct kvm *kvm, - struct kvm_userspace_memory_region *mem); + struct kvm_userspace_memory_region *mem, + struct kvm_memory_slot old); extern int kvm_vm_ioctl_get_smmu_info(struct kvm *kvm, struct kvm_ppc_smmu_info *info); +extern void kvmppc_core_flush_memslot(struct kvm *kvm, + struct kvm_memory_slot *memslot); extern int kvmppc_bookehv_init(void); extern void kvmppc_bookehv_exit(void); diff --git a/arch/powerpc/kvm/book3s_64_mmu_hv.c b/arch/powerpc/kvm/book3s_64_mmu_hv.c index a389cc6..f598366 100644 --- a/arch/powerpc/kvm/book3s_64_mmu_hv.c +++ b/arch/powerpc/kvm/book3s_64_mmu_hv.c @@ -851,7 +851,8 @@ static int kvm_unmap_rmapp(struct kvm *kvm, unsigned long *rmapp, psize = hpte_page_size(hptep[0], ptel); if ((hptep[0] & HPTE_V_VALID) && hpte_rpn(ptel, psize) = gfn) { - hptep[0] |= HPTE_V_ABSENT; + if (kvm->arch.using_mmu_notifiers) + hptep[0] |= HPTE_V_ABSENT; kvmppc_invalidate_hpte(kvm, hptep, i); /* Harvest R and C */ rcbits = hptep[1] & (HPTE_R_R | HPTE_R_C); @@ -878,6 +879,28 @@ int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end) return 0; } +void kvmppc_core_flush_memslot(struct kvm *kvm, struct kvm_memory_slot *memslot) +{ + unsigned long *rmapp; + unsigned long gfn; + unsigned long n; + + rmapp = memslot->arch.rmap; + gfn = memslot->base_gfn; + for (n = memslot->npages; n; --n) { + /* + * Testing the present bit without locking is OK because + * the memslot has been marked invalid already, and hence + * no new HPTEs referencing this page can be created, + * thus the present bit can't go from 0 to 1. + */ + if (*rmapp & KVMPPC_RMAP_PRESENT) + kvm_unmap_rmapp(kvm, rmapp, gfn); + ++rmapp; + ++gfn; + } +} + static int kvm_age_rmapp(struct kvm *kvm, unsigned long *rmapp, unsigned long gfn) { @@ -1031,16 +1054,16 @@ static int kvm_test_clear_dirty(struct kvm *kvm, unsigned long *rmapp) return ret; } -long kvmppc_hv_get_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot) +long kvmppc_hv_get_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot, + unsigned long *map) { unsigned long i; - unsigned long *rmapp, *map; + unsigned long *rmapp; preempt_disable(); rmapp = memslot->arch.rmap; - map = memslot->dirty_bitmap; for (i = 0; i < memslot->npages; ++i) { - if (kvm_test_clear_dirty(kvm, rmapp)) + if (kvm_test_clear_dirty(kvm, rmapp) && map) __set_bit_le(i, map); ++rmapp; } diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index 817837d..38c7f1b 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -1288,7 +1288,7 @@ int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log) n = kvm_dirty_bitmap_bytes(memslot); memset(memslot->dirty_bitmap, 0, n); - r = kvmppc_hv_get_dirty_log(kvm, memslot); + r = kvmppc_hv_get_dirty_log(kvm, memslot, memslot->dirty_bitmap); if (r) goto out; @@ -1378,8 +1378,22 @@ int kvmppc_core_prepare_memory_region(struct kvm *kvm, } void kvmppc_core_commit_memory_region(struct kvm *kvm, - struct kvm_userspace_memory_region *mem) + struct kvm_userspace_memory_region *mem, + struct kvm_memory_slot old) { + unsigned long npages = mem->memory_size >> PAGE_SHIFT; + struct kvm_memory_slot *memslot; + + if (npages && old.npages) { + /* + * If modifying a memslot, reset all the rmap dirty bits. + * If this is a new memslot, we don't need to do anything + * since the rmap array starts out as all zeroes, + * i.e. no pages are dirty. + */ + memslot = id_to_memslot(kvm->memslots, mem->slot); + kvmppc_hv_get_dirty_log(kvm, memslot, NULL); + } } static int kvmppc_hv_setup_htab_rma(struct kvm_vcpu *vcpu) diff --git a/arch/powerpc/kvm/book3s_hv_rm_mmu.c b/arch/powerpc/kvm/book3s_hv_rm_mmu.c index 63eb94e..9955216 100644 --- a/arch/powerpc/kvm/book3s_hv_rm_mmu.c +++ b/arch/powerpc/kvm/book3s_hv_rm_mmu.c @@ -81,7 +81,7 @@ static void remove_revmap_chain(struct kvm *kvm, long pte_index, ptel = rev->guest_rpte |= rcbits; gfn = hpte_rpn(ptel, hpte_page_size(hpte_v, ptel)); memslot = __gfn_to_memslot(kvm_memslots(kvm), gfn); - if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID)) + if (!memslot) return; rmap = real_vmalloc_addr(&memslot->arch.rmap[gfn - memslot->base_gfn]); diff --git a/arch/powerpc/kvm/book3s_pr.c b/arch/powerpc/kvm/book3s_pr.c index 53f65a2..016e1ed 100644 --- a/arch/powerpc/kvm/book3s_pr.c +++ b/arch/powerpc/kvm/book3s_pr.c @@ -1200,7 +1200,12 @@ int kvmppc_core_prepare_memory_region(struct kvm *kvm, } void kvmppc_core_commit_memory_region(struct kvm *kvm, - struct kvm_userspace_memory_region *mem) + struct kvm_userspace_memory_region *mem, + struct kvm_memory_slot old) +{ +} + +void kvmppc_core_flush_memslot(struct kvm *kvm, struct kvm_memory_slot *memslot) { } diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c index 0e66b46..c91f8be 100644 --- a/arch/powerpc/kvm/booke.c +++ b/arch/powerpc/kvm/booke.c @@ -1272,7 +1272,12 @@ int kvmppc_core_prepare_memory_region(struct kvm *kvm, } void kvmppc_core_commit_memory_region(struct kvm *kvm, - struct kvm_userspace_memory_region *mem) + struct kvm_userspace_memory_region *mem, + struct kvm_memory_slot old) +{ +} + +void kvmppc_core_flush_memslot(struct kvm *kvm, struct kvm_memory_slot *memslot) { } diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c index 3a29f29..229627e 100644 --- a/arch/powerpc/kvm/powerpc.c +++ b/arch/powerpc/kvm/powerpc.c @@ -324,7 +324,7 @@ void kvm_arch_commit_memory_region(struct kvm *kvm, struct kvm_memory_slot old, int user_alloc) { - kvmppc_core_commit_memory_region(kvm, mem); + kvmppc_core_commit_memory_region(kvm, mem, old); } void kvm_arch_flush_shadow_all(struct kvm *kvm) @@ -334,6 +334,7 @@ void kvm_arch_flush_shadow_all(struct kvm *kvm) void kvm_arch_flush_shadow_memslot(struct kvm *kvm, struct kvm_memory_slot *slot) { + kvmppc_core_flush_memslot(kvm, slot); } struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id) -- 1.7.10.rc3.219.g53414
next prev parent reply other threads:[~2012-09-11 23:28 UTC|newest] Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top 2012-09-11 23:26 [PATCH 0/3] KVM: PPC: Memslot handling improvements Paul Mackerras 2012-09-11 23:26 ` Paul Mackerras 2012-09-11 23:27 ` [PATCH 1/3] KVM: PPC: Book3S HV: Take the SRCU read lock before looking up memslots Paul Mackerras 2012-09-11 23:27 ` Paul Mackerras 2012-09-11 23:27 ` [PATCH 2/3] KVM: PPC: Move kvm->arch.slot_phys into memslot.arch Paul Mackerras 2012-09-11 23:27 ` Paul Mackerras 2012-09-11 23:28 ` Paul Mackerras [this message] 2012-09-11 23:28 ` [PATCH 3/3] KVM: PPC: Book3S HV: Handle memory slot deletion and modification correctly Paul Mackerras 2012-09-13 16:43 ` [PATCH 0/3] KVM: PPC: Memslot handling improvements Alexander Graf 2012-09-13 16:43 ` Alexander Graf
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