| Message ID | 20220310140911.50924-12-chao.p.peng@linux.intel.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | KVM: mm: fd-based approach for supporting KVM guest private memory | expand |
On Thu, Mar 10, 2022, Chao Peng wrote: > diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c > index 67349421eae3..52319f49d58a 100644 > --- a/virt/kvm/kvm_main.c > +++ b/virt/kvm/kvm_main.c > @@ -841,8 +841,43 @@ static int kvm_init_mmu_notifier(struct kvm *kvm) > #endif /* CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER */ > > #ifdef CONFIG_MEMFILE_NOTIFIER > +static void kvm_memfile_notifier_handler(struct memfile_notifier *notifier, > + pgoff_t start, pgoff_t end) > +{ > + int idx; > + struct kvm_memory_slot *slot = container_of(notifier, > + struct kvm_memory_slot, > + notifier); > + struct kvm_gfn_range gfn_range = { > + .slot = slot, > + .start = start - (slot->private_offset >> PAGE_SHIFT), > + .end = end - (slot->private_offset >> PAGE_SHIFT), > + .may_block = true, > + }; > + struct kvm *kvm = slot->kvm; > + > + gfn_range.start = max(gfn_range.start, slot->base_gfn); > + gfn_range.end = min(gfn_range.end, slot->base_gfn + slot->npages); > + > + if (gfn_range.start >= gfn_range.end) > + return; > + > + idx = srcu_read_lock(&kvm->srcu); > + KVM_MMU_LOCK(kvm); > + kvm_unmap_gfn_range(kvm, &gfn_range); > + kvm_flush_remote_tlbs(kvm); This should check the result of kvm_unmap_gfn_range() and flush only if necessary. kvm->mmu_notifier_seq needs to be incremented, otherwise KVM will incorrectly install a SPTE if the mapping is zapped between retrieving the pfn in faultin and installing it after acquire mmu_lock. > + KVM_MMU_UNLOCK(kvm); > + srcu_read_unlock(&kvm->srcu, idx); > +} > + > +static struct memfile_notifier_ops kvm_memfile_notifier_ops = { > + .invalidate = kvm_memfile_notifier_handler, > + .fallocate = kvm_memfile_notifier_handler, > +}; > + > static inline int kvm_memfile_register(struct kvm_memory_slot *slot) > { > + slot->notifier.ops = &kvm_memfile_notifier_ops; > return memfile_register_notifier(file_inode(slot->private_file), > &slot->notifier, > &slot->pfn_ops); > @@ -1963,6 +1998,7 @@ int __kvm_set_memory_region(struct kvm *kvm, > new->private_file = file; > new->private_offset = mem->flags & KVM_MEM_PRIVATE ? > region_ext->private_offset : 0; > + new->kvm = kvm; > > r = kvm_set_memslot(kvm, old, new, change); > if (!r) > -- > 2.17.1 >
On Thu, Mar 10, 2022 at 10:09:09PM +0800, Chao Peng wrote: > KVM gets notified when memory pages changed in the memory backing store. > When userspace allocates the memory with fallocate() or frees memory > with fallocate(FALLOC_FL_PUNCH_HOLE), memory backing store calls into > KVM fallocate/invalidate callbacks respectively. To ensure KVM never > maps both the private and shared variants of a GPA into the guest, in > the fallocate callback, we should zap the existing shared mapping and > in the invalidate callback we should zap the existing private mapping. > > In the callbacks, KVM firstly converts the offset range into the > gfn_range and then calls existing kvm_unmap_gfn_range() which will zap > the shared or private mapping. Both callbacks pass in a memslot > reference but we need 'kvm' so add a reference in memslot structure. > > Signed-off-by: Yu Zhang <yu.c.zhang@linux.intel.com> > Signed-off-by: Chao Peng <chao.p.peng@linux.intel.com> > --- > include/linux/kvm_host.h | 3 ++- > virt/kvm/kvm_main.c | 36 ++++++++++++++++++++++++++++++++++++ > 2 files changed, 38 insertions(+), 1 deletion(-) > > diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h > index 9b175aeca63f..186b9b981a65 100644 > --- a/include/linux/kvm_host.h > +++ b/include/linux/kvm_host.h > @@ -236,7 +236,7 @@ bool kvm_setup_async_pf(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, > int kvm_async_pf_wakeup_all(struct kvm_vcpu *vcpu); > #endif > > -#ifdef KVM_ARCH_WANT_MMU_NOTIFIER > +#if defined(KVM_ARCH_WANT_MMU_NOTIFIER) || defined(CONFIG_MEMFILE_NOTIFIER) > struct kvm_gfn_range { > struct kvm_memory_slot *slot; > gfn_t start; > @@ -568,6 +568,7 @@ struct kvm_memory_slot { > loff_t private_offset; > struct memfile_pfn_ops *pfn_ops; > struct memfile_notifier notifier; > + struct kvm *kvm; > }; > > static inline bool kvm_slot_is_private(const struct kvm_memory_slot *slot) > diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c > index 67349421eae3..52319f49d58a 100644 > --- a/virt/kvm/kvm_main.c > +++ b/virt/kvm/kvm_main.c > @@ -841,8 +841,43 @@ static int kvm_init_mmu_notifier(struct kvm *kvm) > #endif /* CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER */ > > #ifdef CONFIG_MEMFILE_NOTIFIER > +static void kvm_memfile_notifier_handler(struct memfile_notifier *notifier, > + pgoff_t start, pgoff_t end) > +{ > + int idx; > + struct kvm_memory_slot *slot = container_of(notifier, > + struct kvm_memory_slot, > + notifier); > + struct kvm_gfn_range gfn_range = { > + .slot = slot, > + .start = start - (slot->private_offset >> PAGE_SHIFT), > + .end = end - (slot->private_offset >> PAGE_SHIFT), > + .may_block = true, > + }; > + struct kvm *kvm = slot->kvm; > + > + gfn_range.start = max(gfn_range.start, slot->base_gfn); > + gfn_range.end = min(gfn_range.end, slot->base_gfn + slot->npages); > + > + if (gfn_range.start >= gfn_range.end) > + return; > + > + idx = srcu_read_lock(&kvm->srcu); > + KVM_MMU_LOCK(kvm); > + kvm_unmap_gfn_range(kvm, &gfn_range); > + kvm_flush_remote_tlbs(kvm); > + KVM_MMU_UNLOCK(kvm); > + srcu_read_unlock(&kvm->srcu, idx); Should this also invalidate gfn_to_pfn_cache mappings? Otherwise it seems possible the kernel might end up inadvertantly writing to now-private guest memory via a now-stale gfn_to_pfn_cache entry.
On Tue, Apr 05, 2022, Michael Roth wrote: > On Thu, Mar 10, 2022 at 10:09:09PM +0800, Chao Peng wrote: > > static inline bool kvm_slot_is_private(const struct kvm_memory_slot *slot) > > diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c > > index 67349421eae3..52319f49d58a 100644 > > --- a/virt/kvm/kvm_main.c > > +++ b/virt/kvm/kvm_main.c > > @@ -841,8 +841,43 @@ static int kvm_init_mmu_notifier(struct kvm *kvm) > > #endif /* CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER */ > > > > #ifdef CONFIG_MEMFILE_NOTIFIER > > +static void kvm_memfile_notifier_handler(struct memfile_notifier *notifier, > > + pgoff_t start, pgoff_t end) > > +{ > > + int idx; > > + struct kvm_memory_slot *slot = container_of(notifier, > > + struct kvm_memory_slot, > > + notifier); > > + struct kvm_gfn_range gfn_range = { > > + .slot = slot, > > + .start = start - (slot->private_offset >> PAGE_SHIFT), > > + .end = end - (slot->private_offset >> PAGE_SHIFT), > > + .may_block = true, > > + }; > > + struct kvm *kvm = slot->kvm; > > + > > + gfn_range.start = max(gfn_range.start, slot->base_gfn); > > + gfn_range.end = min(gfn_range.end, slot->base_gfn + slot->npages); > > + > > + if (gfn_range.start >= gfn_range.end) > > + return; > > + > > + idx = srcu_read_lock(&kvm->srcu); > > + KVM_MMU_LOCK(kvm); > > + kvm_unmap_gfn_range(kvm, &gfn_range); > > + kvm_flush_remote_tlbs(kvm); > > + KVM_MMU_UNLOCK(kvm); > > + srcu_read_unlock(&kvm->srcu, idx); > > Should this also invalidate gfn_to_pfn_cache mappings? Otherwise it seems > possible the kernel might end up inadvertantly writing to now-private guest > memory via a now-stale gfn_to_pfn_cache entry. Yes. Ideally we'd get these flows to share common code and avoid these goofs. I tried very briefly but they're just different enough to make it ugly.
On Tue, Mar 29, 2022 at 07:23:04PM +0000, Sean Christopherson wrote: > On Thu, Mar 10, 2022, Chao Peng wrote: > > diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c > > index 67349421eae3..52319f49d58a 100644 > > --- a/virt/kvm/kvm_main.c > > +++ b/virt/kvm/kvm_main.c > > @@ -841,8 +841,43 @@ static int kvm_init_mmu_notifier(struct kvm *kvm) > > #endif /* CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER */ > > > > #ifdef CONFIG_MEMFILE_NOTIFIER > > +static void kvm_memfile_notifier_handler(struct memfile_notifier *notifier, > > + pgoff_t start, pgoff_t end) > > +{ > > + int idx; > > + struct kvm_memory_slot *slot = container_of(notifier, > > + struct kvm_memory_slot, > > + notifier); > > + struct kvm_gfn_range gfn_range = { > > + .slot = slot, > > + .start = start - (slot->private_offset >> PAGE_SHIFT), > > + .end = end - (slot->private_offset >> PAGE_SHIFT), > > + .may_block = true, > > + }; > > + struct kvm *kvm = slot->kvm; > > + > > + gfn_range.start = max(gfn_range.start, slot->base_gfn); > > + gfn_range.end = min(gfn_range.end, slot->base_gfn + slot->npages); > > + > > + if (gfn_range.start >= gfn_range.end) > > + return; > > + > > + idx = srcu_read_lock(&kvm->srcu); > > + KVM_MMU_LOCK(kvm); > > + kvm_unmap_gfn_range(kvm, &gfn_range); > > + kvm_flush_remote_tlbs(kvm); > > This should check the result of kvm_unmap_gfn_range() and flush only if necessary. Yep. > > kvm->mmu_notifier_seq needs to be incremented, otherwise KVM will incorrectly > install a SPTE if the mapping is zapped between retrieving the pfn in faultin and > installing it after acquire mmu_lock. Good catch. Chao > > > > + KVM_MMU_UNLOCK(kvm); > > + srcu_read_unlock(&kvm->srcu, idx); > > +} > > + > > +static struct memfile_notifier_ops kvm_memfile_notifier_ops = { > > + .invalidate = kvm_memfile_notifier_handler, > > + .fallocate = kvm_memfile_notifier_handler, > > +}; > > + > > static inline int kvm_memfile_register(struct kvm_memory_slot *slot) > > { > > + slot->notifier.ops = &kvm_memfile_notifier_ops; > > return memfile_register_notifier(file_inode(slot->private_file), > > &slot->notifier, > > &slot->pfn_ops); > > @@ -1963,6 +1998,7 @@ int __kvm_set_memory_region(struct kvm *kvm, > > new->private_file = file; > > new->private_offset = mem->flags & KVM_MEM_PRIVATE ? > > region_ext->private_offset : 0; > > + new->kvm = kvm; > > > > r = kvm_set_memslot(kvm, old, new, change); > > if (!r) > > -- > > 2.17.1 > >
On Thu, Mar 10, 2022 at 6:11 AM Chao Peng <chao.p.peng@linux.intel.com> wrote: > > KVM gets notified when memory pages changed in the memory backing store. > When userspace allocates the memory with fallocate() or frees memory > with fallocate(FALLOC_FL_PUNCH_HOLE), memory backing store calls into > KVM fallocate/invalidate callbacks respectively. To ensure KVM never > maps both the private and shared variants of a GPA into the guest, in > the fallocate callback, we should zap the existing shared mapping and > in the invalidate callback we should zap the existing private mapping. > > In the callbacks, KVM firstly converts the offset range into the > gfn_range and then calls existing kvm_unmap_gfn_range() which will zap > the shared or private mapping. Both callbacks pass in a memslot > reference but we need 'kvm' so add a reference in memslot structure. > > Signed-off-by: Yu Zhang <yu.c.zhang@linux.intel.com> > Signed-off-by: Chao Peng <chao.p.peng@linux.intel.com> > --- > include/linux/kvm_host.h | 3 ++- > virt/kvm/kvm_main.c | 36 ++++++++++++++++++++++++++++++++++++ > 2 files changed, 38 insertions(+), 1 deletion(-) > > diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h > index 9b175aeca63f..186b9b981a65 100644 > --- a/include/linux/kvm_host.h > +++ b/include/linux/kvm_host.h > @@ -236,7 +236,7 @@ bool kvm_setup_async_pf(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, > int kvm_async_pf_wakeup_all(struct kvm_vcpu *vcpu); > #endif > > -#ifdef KVM_ARCH_WANT_MMU_NOTIFIER > +#if defined(KVM_ARCH_WANT_MMU_NOTIFIER) || defined(CONFIG_MEMFILE_NOTIFIER) > struct kvm_gfn_range { > struct kvm_memory_slot *slot; > gfn_t start; > @@ -568,6 +568,7 @@ struct kvm_memory_slot { > loff_t private_offset; > struct memfile_pfn_ops *pfn_ops; > struct memfile_notifier notifier; > + struct kvm *kvm; > }; > > static inline bool kvm_slot_is_private(const struct kvm_memory_slot *slot) > diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c > index 67349421eae3..52319f49d58a 100644 > --- a/virt/kvm/kvm_main.c > +++ b/virt/kvm/kvm_main.c > @@ -841,8 +841,43 @@ static int kvm_init_mmu_notifier(struct kvm *kvm) > #endif /* CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER */ > > #ifdef CONFIG_MEMFILE_NOTIFIER > +static void kvm_memfile_notifier_handler(struct memfile_notifier *notifier, > + pgoff_t start, pgoff_t end) > +{ > + int idx; > + struct kvm_memory_slot *slot = container_of(notifier, > + struct kvm_memory_slot, > + notifier); > + struct kvm_gfn_range gfn_range = { > + .slot = slot, > + .start = start - (slot->private_offset >> PAGE_SHIFT), > + .end = end - (slot->private_offset >> PAGE_SHIFT), > + .may_block = true, > + }; > + struct kvm *kvm = slot->kvm; > + > + gfn_range.start = max(gfn_range.start, slot->base_gfn); gfn_range.start seems to be page offset within the file. Should this rather be: gfn_range.start = slot->base_gfn + min(gfn_range.start, slot->npages); > + gfn_range.end = min(gfn_range.end, slot->base_gfn + slot->npages); > + Similar to previous comment, should this rather be: gfn_range.end = slot->base_gfn + min(gfn_range.end, slot->npages); > + if (gfn_range.start >= gfn_range.end) > + return; > + > + idx = srcu_read_lock(&kvm->srcu); > + KVM_MMU_LOCK(kvm); > + kvm_unmap_gfn_range(kvm, &gfn_range); > + kvm_flush_remote_tlbs(kvm); > + KVM_MMU_UNLOCK(kvm); > + srcu_read_unlock(&kvm->srcu, idx); > +} > + > +static struct memfile_notifier_ops kvm_memfile_notifier_ops = { > + .invalidate = kvm_memfile_notifier_handler, > + .fallocate = kvm_memfile_notifier_handler, > +}; > + > static inline int kvm_memfile_register(struct kvm_memory_slot *slot) > { > + slot->notifier.ops = &kvm_memfile_notifier_ops; > return memfile_register_notifier(file_inode(slot->private_file), > &slot->notifier, > &slot->pfn_ops); > @@ -1963,6 +1998,7 @@ int __kvm_set_memory_region(struct kvm *kvm, > new->private_file = file; > new->private_offset = mem->flags & KVM_MEM_PRIVATE ? > region_ext->private_offset : 0; > + new->kvm = kvm; > > r = kvm_set_memslot(kvm, old, new, change); > if (!r) > -- > 2.17.1 >
On Tue, Apr 19, 2022 at 03:43:56PM -0700, Vishal Annapurve wrote: > On Thu, Mar 10, 2022 at 6:11 AM Chao Peng <chao.p.peng@linux.intel.com> wrote: > > > > KVM gets notified when memory pages changed in the memory backing store. > > When userspace allocates the memory with fallocate() or frees memory > > with fallocate(FALLOC_FL_PUNCH_HOLE), memory backing store calls into > > KVM fallocate/invalidate callbacks respectively. To ensure KVM never > > maps both the private and shared variants of a GPA into the guest, in > > the fallocate callback, we should zap the existing shared mapping and > > in the invalidate callback we should zap the existing private mapping. > > > > In the callbacks, KVM firstly converts the offset range into the > > gfn_range and then calls existing kvm_unmap_gfn_range() which will zap > > the shared or private mapping. Both callbacks pass in a memslot > > reference but we need 'kvm' so add a reference in memslot structure. > > > > Signed-off-by: Yu Zhang <yu.c.zhang@linux.intel.com> > > Signed-off-by: Chao Peng <chao.p.peng@linux.intel.com> > > --- > > include/linux/kvm_host.h | 3 ++- > > virt/kvm/kvm_main.c | 36 ++++++++++++++++++++++++++++++++++++ > > 2 files changed, 38 insertions(+), 1 deletion(-) > > > > diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h > > index 9b175aeca63f..186b9b981a65 100644 > > --- a/include/linux/kvm_host.h > > +++ b/include/linux/kvm_host.h > > @@ -236,7 +236,7 @@ bool kvm_setup_async_pf(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, > > int kvm_async_pf_wakeup_all(struct kvm_vcpu *vcpu); > > #endif > > > > -#ifdef KVM_ARCH_WANT_MMU_NOTIFIER > > +#if defined(KVM_ARCH_WANT_MMU_NOTIFIER) || defined(CONFIG_MEMFILE_NOTIFIER) > > struct kvm_gfn_range { > > struct kvm_memory_slot *slot; > > gfn_t start; > > @@ -568,6 +568,7 @@ struct kvm_memory_slot { > > loff_t private_offset; > > struct memfile_pfn_ops *pfn_ops; > > struct memfile_notifier notifier; > > + struct kvm *kvm; > > }; > > > > static inline bool kvm_slot_is_private(const struct kvm_memory_slot *slot) > > diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c > > index 67349421eae3..52319f49d58a 100644 > > --- a/virt/kvm/kvm_main.c > > +++ b/virt/kvm/kvm_main.c > > @@ -841,8 +841,43 @@ static int kvm_init_mmu_notifier(struct kvm *kvm) > > #endif /* CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER */ > > > > #ifdef CONFIG_MEMFILE_NOTIFIER > > +static void kvm_memfile_notifier_handler(struct memfile_notifier *notifier, > > + pgoff_t start, pgoff_t end) > > +{ > > + int idx; > > + struct kvm_memory_slot *slot = container_of(notifier, > > + struct kvm_memory_slot, > > + notifier); > > + struct kvm_gfn_range gfn_range = { > > + .slot = slot, > > + .start = start - (slot->private_offset >> PAGE_SHIFT), > > + .end = end - (slot->private_offset >> PAGE_SHIFT), > > + .may_block = true, > > + }; > > + struct kvm *kvm = slot->kvm; > > + > > + gfn_range.start = max(gfn_range.start, slot->base_gfn); > > gfn_range.start seems to be page offset within the file. Should this rather be: > gfn_range.start = slot->base_gfn + min(gfn_range.start, slot->npages); Right. For start we don't really need care about the uppper bound here (will check below), so this should be enough: gfn_range.start = slot->base_gfn + gfn_range.start; > > > + gfn_range.end = min(gfn_range.end, slot->base_gfn + slot->npages); > > + > > Similar to previous comment, should this rather be: > gfn_range.end = slot->base_gfn + min(gfn_range.end, slot->npages); This is correct. Thanks, Chao > > > + if (gfn_range.start >= gfn_range.end) > > + return; > > + > > + idx = srcu_read_lock(&kvm->srcu); > > + KVM_MMU_LOCK(kvm); > > + kvm_unmap_gfn_range(kvm, &gfn_range); > > + kvm_flush_remote_tlbs(kvm); > > + KVM_MMU_UNLOCK(kvm); > > + srcu_read_unlock(&kvm->srcu, idx); > > +} > > + > > +static struct memfile_notifier_ops kvm_memfile_notifier_ops = { > > + .invalidate = kvm_memfile_notifier_handler, > > + .fallocate = kvm_memfile_notifier_handler, > > +}; > > + > > static inline int kvm_memfile_register(struct kvm_memory_slot *slot) > > { > > + slot->notifier.ops = &kvm_memfile_notifier_ops; > > return memfile_register_notifier(file_inode(slot->private_file), > > &slot->notifier, > > &slot->pfn_ops); > > @@ -1963,6 +1998,7 @@ int __kvm_set_memory_region(struct kvm *kvm, > > new->private_file = file; > > new->private_offset = mem->flags & KVM_MEM_PRIVATE ? > > region_ext->private_offset : 0; > > + new->kvm = kvm; > > > > r = kvm_set_memslot(kvm, old, new, change); > > if (!r) > > -- > > 2.17.1 > >
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 9b175aeca63f..186b9b981a65 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -236,7 +236,7 @@ bool kvm_setup_async_pf(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, int kvm_async_pf_wakeup_all(struct kvm_vcpu *vcpu); #endif -#ifdef KVM_ARCH_WANT_MMU_NOTIFIER +#if defined(KVM_ARCH_WANT_MMU_NOTIFIER) || defined(CONFIG_MEMFILE_NOTIFIER) struct kvm_gfn_range { struct kvm_memory_slot *slot; gfn_t start; @@ -568,6 +568,7 @@ struct kvm_memory_slot { loff_t private_offset; struct memfile_pfn_ops *pfn_ops; struct memfile_notifier notifier; + struct kvm *kvm; }; static inline bool kvm_slot_is_private(const struct kvm_memory_slot *slot) diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 67349421eae3..52319f49d58a 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -841,8 +841,43 @@ static int kvm_init_mmu_notifier(struct kvm *kvm) #endif /* CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER */ #ifdef CONFIG_MEMFILE_NOTIFIER +static void kvm_memfile_notifier_handler(struct memfile_notifier *notifier, + pgoff_t start, pgoff_t end) +{ + int idx; + struct kvm_memory_slot *slot = container_of(notifier, + struct kvm_memory_slot, + notifier); + struct kvm_gfn_range gfn_range = { + .slot = slot, + .start = start - (slot->private_offset >> PAGE_SHIFT), + .end = end - (slot->private_offset >> PAGE_SHIFT), + .may_block = true, + }; + struct kvm *kvm = slot->kvm; + + gfn_range.start = max(gfn_range.start, slot->base_gfn); + gfn_range.end = min(gfn_range.end, slot->base_gfn + slot->npages); + + if (gfn_range.start >= gfn_range.end) + return; + + idx = srcu_read_lock(&kvm->srcu); + KVM_MMU_LOCK(kvm); + kvm_unmap_gfn_range(kvm, &gfn_range); + kvm_flush_remote_tlbs(kvm); + KVM_MMU_UNLOCK(kvm); + srcu_read_unlock(&kvm->srcu, idx); +} + +static struct memfile_notifier_ops kvm_memfile_notifier_ops = { + .invalidate = kvm_memfile_notifier_handler, + .fallocate = kvm_memfile_notifier_handler, +}; + static inline int kvm_memfile_register(struct kvm_memory_slot *slot) { + slot->notifier.ops = &kvm_memfile_notifier_ops; return memfile_register_notifier(file_inode(slot->private_file), &slot->notifier, &slot->pfn_ops); @@ -1963,6 +1998,7 @@ int __kvm_set_memory_region(struct kvm *kvm, new->private_file = file; new->private_offset = mem->flags & KVM_MEM_PRIVATE ? region_ext->private_offset : 0; + new->kvm = kvm; r = kvm_set_memslot(kvm, old, new, change); if (!r)