diff mbox series

[v10,060/108] KVM: Add functions to set GFN to private or shared

Message ID c834432220f04c39a8dfa6ac3838446e6c06c9e9.1667110240.git.isaku.yamahata@intel.com (mailing list archive)
State New, archived
Headers show
Series KVM TDX basic feature support | expand

Commit Message

Isaku Yamahata Oct. 30, 2022, 6:23 a.m. UTC 
From: Isaku Yamahata <isaku.yamahata@intel.com>

TDX KVM support needs to track whether GFN is private or shared.  Introduce
functions to set whether GFN is private or shared and pre-allocate memory
for xarray.

Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
---
 include/linux/kvm_host.h | 11 ++++++
 virt/kvm/kvm_main.c      | 74 ++++++++++++++++++++++++++++++++++++++++
 2 files changed, 85 insertions(+)

Comments

Xiaoyao Li Nov. 1, 2022, 10:21 a.m. UTC | #1 
On 10/30/2022 2:23 PM, isaku.yamahata@intel.com wrote:
> From: Isaku Yamahata <isaku.yamahata@intel.com>
> 
> TDX KVM support needs to track whether GFN is private or shared.  Introduce
> functions to set whether GFN is private or shared and pre-allocate memory
> for xarray.
> 
> Suggested-by: Sean Christopherson <seanjc@google.com>
> Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
> ---
>   include/linux/kvm_host.h | 11 ++++++
>   virt/kvm/kvm_main.c      | 74 ++++++++++++++++++++++++++++++++++++++++
>   2 files changed, 85 insertions(+)
> 
> diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
> index a0b64308d240..fac07886ab39 100644
> --- a/include/linux/kvm_host.h
> +++ b/include/linux/kvm_host.h
> @@ -2307,9 +2307,20 @@ static inline void kvm_account_pgtable_pages(void *virt, int nr)
>   #define KVM_MEM_ATTR_PRIVATE	0x0002
>   
>   #ifdef __KVM_HAVE_ARCH_UPDATE_MEM_ATTR
> +/* memory attr on [start, end) */
> +int kvm_vm_reserve_mem_attr(struct kvm *kvm, gfn_t start, gfn_t end);
> +int kvm_vm_set_mem_attr(struct kvm *kvm, int attr, gfn_t start, gfn_t end);
>   void kvm_arch_update_mem_attr(struct kvm *kvm, struct kvm_memory_slot *slot,
>   			      unsigned int attr, gfn_t start, gfn_t end);
>   #else
> +static inline int kvm_vm_reserve_mem_attr(struct kvm *kvm, gfn_t start, gfn_t end)
> +{
> +	return -EOPNOTSUPP;
> +}
> +static inline int kvm_vm_set_mem_attr(struct kvm *kvm, int attr, gfn_t start, gfn_t end)
> +{
> +	return -EOPNOTSUPP;
> +}
>   static inline void kvm_arch_update_mem_attr(struct kvm *kvm,
>   					    struct kvm_memory_slot *slot,
>   					    unsigned int attr,
> diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
> index 9f82b03a8118..f0e77b65939b 100644
> --- a/virt/kvm/kvm_main.c
> +++ b/virt/kvm/kvm_main.c
> @@ -1121,6 +1121,80 @@ static inline void kvm_restrictedmem_unregister(struct kvm_memory_slot *slot)
>   					  &slot->notifier);
>   }
>   
> +/*
> + * Reserve memory for [start, end) so that the next set oepration won't fail
> + * with -ENOMEM.
> + */
> +int kvm_vm_reserve_mem_attr(struct kvm *kvm, gfn_t start, gfn_t end)
> +{
> +	int r = 0;
> +	gfn_t gfn;
> +
> +	xa_lock(&kvm->mem_attr_array);
> +	for (gfn = start; gfn < end; gfn++) {
> +		r = __xa_insert(&kvm->mem_attr_array, gfn, NULL, GFP_KERNEL_ACCOUNT);
> +		if (r == -EBUSY)
> +			r = 0;
> +		if (r)
> +			break;
> +	}
> +	xa_unlock(&kvm->mem_attr_array);
> +
> +	return r;
> +}
> +EXPORT_SYMBOL_GPL(kvm_vm_reserve_mem_attr);
> +
> +/* Set memory attr for [start, end) */
> +int kvm_vm_set_mem_attr(struct kvm *kvm, int attr, gfn_t start, gfn_t end)
> +{
> +	void *entry;
> +	gfn_t gfn;
> +	int r;
> +	int i;
> +
> +	/* By default, the entry is private. */
> +	switch (attr) {
> +	case KVM_MEM_ATTR_PRIVATE:
> +		entry = NULL;
> +		break;
> +	case KVM_MEM_ATTR_SHARED:
> +		entry = xa_mk_value(KVM_MEM_ATTR_SHARED);
> +		break;
> +	default:
> +		WARN_ON_ONCE(1);
> +		return -EINVAL;
> +	}
> +
> +	WARN_ON_ONCE(start >= end);
> +	for (gfn = start; gfn < end; gfn++) {
> +		r = xa_err(xa_store(&kvm->mem_attr_array, gfn, entry,
> +				    GFP_KERNEL_ACCOUNT));
> +		if (r)
> +			break;
> +	}
> +	if (start >= gfn)
> +		return r;
> +
> +	end = gfn;
> +	for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++) {
> +		struct kvm_memslot_iter iter;
> +		struct kvm_memory_slot *slot;
> +		struct kvm_memslots *slots;
> +
> +		slots = __kvm_memslots(kvm, i);
> +		kvm_for_each_memslot_in_gfn_range(&iter, slots, start, end) {

slot needs to be set as

			slot = iter.slot;

> +			gfn_t s = max(start, slot->base_gfn);
> +			gfn_t e = min(end, slot->base_gfn + slot->npages);
> +
> +			WARN_ON_ONCE(s >= e);
> +			kvm_arch_update_mem_attr(kvm, slot, attr, s, e);
> +		}
> +	}
> +
> +	return r;
> +}
> +EXPORT_SYMBOL_GPL(kvm_vm_set_mem_attr);
> +
>   #else /* !CONFIG_HAVE_KVM_RESTRICTED_MEM */
>   
>   static inline void kvm_restrictedmem_register(struct kvm_memory_slot *slot)
Isaku Yamahata Nov. 3, 2022, 2:01 a.m. UTC | #2 
On Tue, Nov 01, 2022 at 06:21:26PM +0800,
Xiaoyao Li <xiaoyao.li@intel.com> wrote:

> On 10/30/2022 2:23 PM, isaku.yamahata@intel.com wrote:
> > From: Isaku Yamahata <isaku.yamahata@intel.com>
> > 
> > TDX KVM support needs to track whether GFN is private or shared.  Introduce
> > functions to set whether GFN is private or shared and pre-allocate memory
> > for xarray.
> > 
> > Suggested-by: Sean Christopherson <seanjc@google.com>
> > Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
> > ---
> >   include/linux/kvm_host.h | 11 ++++++
> >   virt/kvm/kvm_main.c      | 74 ++++++++++++++++++++++++++++++++++++++++
> >   2 files changed, 85 insertions(+)
> > 
> > diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
> > index a0b64308d240..fac07886ab39 100644
> > --- a/include/linux/kvm_host.h
> > +++ b/include/linux/kvm_host.h
> > @@ -2307,9 +2307,20 @@ static inline void kvm_account_pgtable_pages(void *virt, int nr)
> >   #define KVM_MEM_ATTR_PRIVATE	0x0002
> >   #ifdef __KVM_HAVE_ARCH_UPDATE_MEM_ATTR
> > +/* memory attr on [start, end) */
> > +int kvm_vm_reserve_mem_attr(struct kvm *kvm, gfn_t start, gfn_t end);
> > +int kvm_vm_set_mem_attr(struct kvm *kvm, int attr, gfn_t start, gfn_t end);
> >   void kvm_arch_update_mem_attr(struct kvm *kvm, struct kvm_memory_slot *slot,
> >   			      unsigned int attr, gfn_t start, gfn_t end);
> >   #else
> > +static inline int kvm_vm_reserve_mem_attr(struct kvm *kvm, gfn_t start, gfn_t end)
> > +{
> > +	return -EOPNOTSUPP;
> > +}
> > +static inline int kvm_vm_set_mem_attr(struct kvm *kvm, int attr, gfn_t start, gfn_t end)
> > +{
> > +	return -EOPNOTSUPP;
> > +}
> >   static inline void kvm_arch_update_mem_attr(struct kvm *kvm,
> >   					    struct kvm_memory_slot *slot,
> >   					    unsigned int attr,
> > diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
> > index 9f82b03a8118..f0e77b65939b 100644
> > --- a/virt/kvm/kvm_main.c
> > +++ b/virt/kvm/kvm_main.c
> > @@ -1121,6 +1121,80 @@ static inline void kvm_restrictedmem_unregister(struct kvm_memory_slot *slot)
> >   					  &slot->notifier);
> >   }
> > +/*
> > + * Reserve memory for [start, end) so that the next set oepration won't fail
> > + * with -ENOMEM.
> > + */
> > +int kvm_vm_reserve_mem_attr(struct kvm *kvm, gfn_t start, gfn_t end)
> > +{
> > +	int r = 0;
> > +	gfn_t gfn;
> > +
> > +	xa_lock(&kvm->mem_attr_array);
> > +	for (gfn = start; gfn < end; gfn++) {
> > +		r = __xa_insert(&kvm->mem_attr_array, gfn, NULL, GFP_KERNEL_ACCOUNT);
> > +		if (r == -EBUSY)
> > +			r = 0;
> > +		if (r)
> > +			break;
> > +	}
> > +	xa_unlock(&kvm->mem_attr_array);
> > +
> > +	return r;
> > +}
> > +EXPORT_SYMBOL_GPL(kvm_vm_reserve_mem_attr);
> > +
> > +/* Set memory attr for [start, end) */
> > +int kvm_vm_set_mem_attr(struct kvm *kvm, int attr, gfn_t start, gfn_t end)
> > +{
> > +	void *entry;
> > +	gfn_t gfn;
> > +	int r;
> > +	int i;
> > +
> > +	/* By default, the entry is private. */
> > +	switch (attr) {
> > +	case KVM_MEM_ATTR_PRIVATE:
> > +		entry = NULL;
> > +		break;
> > +	case KVM_MEM_ATTR_SHARED:
> > +		entry = xa_mk_value(KVM_MEM_ATTR_SHARED);
> > +		break;
> > +	default:
> > +		WARN_ON_ONCE(1);
> > +		return -EINVAL;
> > +	}
> > +
> > +	WARN_ON_ONCE(start >= end);
> > +	for (gfn = start; gfn < end; gfn++) {
> > +		r = xa_err(xa_store(&kvm->mem_attr_array, gfn, entry,
> > +				    GFP_KERNEL_ACCOUNT));
> > +		if (r)
> > +			break;
> > +	}
> > +	if (start >= gfn)
> > +		return r;
> > +
> > +	end = gfn;
> > +	for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++) {
> > +		struct kvm_memslot_iter iter;
> > +		struct kvm_memory_slot *slot;
> > +		struct kvm_memslots *slots;
> > +
> > +		slots = __kvm_memslots(kvm, i);
> > +		kvm_for_each_memslot_in_gfn_range(&iter, slots, start, end) {
> 
> slot needs to be set as
> 
> 			slot = iter.slot;
> 

Thanks, will fix it.
Binbin Wu Nov. 9, 2022, 1:18 p.m. UTC | #3 
On 10/30/2022 2:23 PM, isaku.yamahata@intel.com wrote:
> From: Isaku Yamahata <isaku.yamahata@intel.com>
>
> TDX KVM support needs to track whether GFN is private or shared.  Introduce
> functions to set whether GFN is private or shared and pre-allocate memory
> for xarray.
>
> Suggested-by: Sean Christopherson <seanjc@google.com>
> Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
> ---
>   include/linux/kvm_host.h | 11 ++++++
>   virt/kvm/kvm_main.c      | 74 ++++++++++++++++++++++++++++++++++++++++
>   2 files changed, 85 insertions(+)
>
> diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
> index a0b64308d240..fac07886ab39 100644
> --- a/include/linux/kvm_host.h
> +++ b/include/linux/kvm_host.h
> @@ -2307,9 +2307,20 @@ static inline void kvm_account_pgtable_pages(void *virt, int nr)
>   #define KVM_MEM_ATTR_PRIVATE	0x0002
>   
>   #ifdef __KVM_HAVE_ARCH_UPDATE_MEM_ATTR
> +/* memory attr on [start, end) */
> +int kvm_vm_reserve_mem_attr(struct kvm *kvm, gfn_t start, gfn_t end);
> +int kvm_vm_set_mem_attr(struct kvm *kvm, int attr, gfn_t start, gfn_t end);
>   void kvm_arch_update_mem_attr(struct kvm *kvm, struct kvm_memory_slot *slot,
>   			      unsigned int attr, gfn_t start, gfn_t end);
>   #else
> +static inline int kvm_vm_reserve_mem_attr(struct kvm *kvm, gfn_t start, gfn_t end)
> +{
> +	return -EOPNOTSUPP;
> +}
> +static inline int kvm_vm_set_mem_attr(struct kvm *kvm, int attr, gfn_t start, gfn_t end)
> +{
> +	return -EOPNOTSUPP;
> +}
>   static inline void kvm_arch_update_mem_attr(struct kvm *kvm,
>   					    struct kvm_memory_slot *slot,
>   					    unsigned int attr,
> diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
> index 9f82b03a8118..f0e77b65939b 100644
> --- a/virt/kvm/kvm_main.c
> +++ b/virt/kvm/kvm_main.c
> @@ -1121,6 +1121,80 @@ static inline void kvm_restrictedmem_unregister(struct kvm_memory_slot *slot)
>   					  &slot->notifier);
>   }
>   
> +/*
> + * Reserve memory for [start, end) so that the next set oepration won't fail
> + * with -ENOMEM.
> + */
> +int kvm_vm_reserve_mem_attr(struct kvm *kvm, gfn_t start, gfn_t end)
> +{
> +	int r = 0;
> +	gfn_t gfn;
> +
> +	xa_lock(&kvm->mem_attr_array);
> +	for (gfn = start; gfn < end; gfn++) {
> +		r = __xa_insert(&kvm->mem_attr_array, gfn, NULL, GFP_KERNEL_ACCOUNT);
> +		if (r == -EBUSY)
> +			r = 0;
> +		if (r)
> +			break;
> +	}
> +	xa_unlock(&kvm->mem_attr_array);
> +
> +	return r;
> +}
> +EXPORT_SYMBOL_GPL(kvm_vm_reserve_mem_attr);
> +
> +/* Set memory attr for [start, end) */
> +int kvm_vm_set_mem_attr(struct kvm *kvm, int attr, gfn_t start, gfn_t end)
> +{
> +	void *entry;
> +	gfn_t gfn;
> +	int r;
> +	int i;
> +
> +	/* By default, the entry is private. */
> +	switch (attr) {
> +	case KVM_MEM_ATTR_PRIVATE:
> +		entry = NULL;
> +		break;
> +	case KVM_MEM_ATTR_SHARED:
> +		entry = xa_mk_value(KVM_MEM_ATTR_SHARED);
> +		break;
> +	default:
> +		WARN_ON_ONCE(1);
> +		return -EINVAL;
> +	}
> +
> +	WARN_ON_ONCE(start >= end);
> +	for (gfn = start; gfn < end; gfn++) {
> +		r = xa_err(xa_store(&kvm->mem_attr_array, gfn, entry,
> +				    GFP_KERNEL_ACCOUNT));
> +		if (r)
> +			break;
> +	}
> +	if (start >= gfn)
> +		return r;
> +
> +	end = gfn;
> +	for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++) {
> +		struct kvm_memslot_iter iter;
> +		struct kvm_memory_slot *slot;
> +		struct kvm_memslots *slots;
> +
> +		slots = __kvm_memslots(kvm, i);
> +		kvm_for_each_memslot_in_gfn_range(&iter, slots, start, end) {
> +			gfn_t s = max(start, slot->base_gfn);
> +			gfn_t e = min(end, slot->base_gfn + slot->npages);

slot is not inited.


> +
> +			WARN_ON_ONCE(s >= e);
> +			kvm_arch_update_mem_attr(kvm, slot, attr, s, e);
> +		}
> +	}
> +
> +	return r;
> +}
> +EXPORT_SYMBOL_GPL(kvm_vm_set_mem_attr);
> +
>   #else /* !CONFIG_HAVE_KVM_RESTRICTED_MEM */
>   
>   static inline void kvm_restrictedmem_register(struct kvm_memory_slot *slot)
diff mbox series

Patch

diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index a0b64308d240..fac07886ab39 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -2307,9 +2307,20 @@  static inline void kvm_account_pgtable_pages(void *virt, int nr)
 #define KVM_MEM_ATTR_PRIVATE	0x0002
 
 #ifdef __KVM_HAVE_ARCH_UPDATE_MEM_ATTR
+/* memory attr on [start, end) */
+int kvm_vm_reserve_mem_attr(struct kvm *kvm, gfn_t start, gfn_t end);
+int kvm_vm_set_mem_attr(struct kvm *kvm, int attr, gfn_t start, gfn_t end);
 void kvm_arch_update_mem_attr(struct kvm *kvm, struct kvm_memory_slot *slot,
 			      unsigned int attr, gfn_t start, gfn_t end);
 #else
+static inline int kvm_vm_reserve_mem_attr(struct kvm *kvm, gfn_t start, gfn_t end)
+{
+	return -EOPNOTSUPP;
+}
+static inline int kvm_vm_set_mem_attr(struct kvm *kvm, int attr, gfn_t start, gfn_t end)
+{
+	return -EOPNOTSUPP;
+}
 static inline void kvm_arch_update_mem_attr(struct kvm *kvm,
 					    struct kvm_memory_slot *slot,
 					    unsigned int attr,
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 9f82b03a8118..f0e77b65939b 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -1121,6 +1121,80 @@  static inline void kvm_restrictedmem_unregister(struct kvm_memory_slot *slot)
 					  &slot->notifier);
 }
 
+/*
+ * Reserve memory for [start, end) so that the next set oepration won't fail
+ * with -ENOMEM.
+ */
+int kvm_vm_reserve_mem_attr(struct kvm *kvm, gfn_t start, gfn_t end)
+{
+	int r = 0;
+	gfn_t gfn;
+
+	xa_lock(&kvm->mem_attr_array);
+	for (gfn = start; gfn < end; gfn++) {
+		r = __xa_insert(&kvm->mem_attr_array, gfn, NULL, GFP_KERNEL_ACCOUNT);
+		if (r == -EBUSY)
+			r = 0;
+		if (r)
+			break;
+	}
+	xa_unlock(&kvm->mem_attr_array);
+
+	return r;
+}
+EXPORT_SYMBOL_GPL(kvm_vm_reserve_mem_attr);
+
+/* Set memory attr for [start, end) */
+int kvm_vm_set_mem_attr(struct kvm *kvm, int attr, gfn_t start, gfn_t end)
+{
+	void *entry;
+	gfn_t gfn;
+	int r;
+	int i;
+
+	/* By default, the entry is private. */
+	switch (attr) {
+	case KVM_MEM_ATTR_PRIVATE:
+		entry = NULL;
+		break;
+	case KVM_MEM_ATTR_SHARED:
+		entry = xa_mk_value(KVM_MEM_ATTR_SHARED);
+		break;
+	default:
+		WARN_ON_ONCE(1);
+		return -EINVAL;
+	}
+
+	WARN_ON_ONCE(start >= end);
+	for (gfn = start; gfn < end; gfn++) {
+		r = xa_err(xa_store(&kvm->mem_attr_array, gfn, entry,
+				    GFP_KERNEL_ACCOUNT));
+		if (r)
+			break;
+	}
+	if (start >= gfn)
+		return r;
+
+	end = gfn;
+	for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++) {
+		struct kvm_memslot_iter iter;
+		struct kvm_memory_slot *slot;
+		struct kvm_memslots *slots;
+
+		slots = __kvm_memslots(kvm, i);
+		kvm_for_each_memslot_in_gfn_range(&iter, slots, start, end) {
+			gfn_t s = max(start, slot->base_gfn);
+			gfn_t e = min(end, slot->base_gfn + slot->npages);
+
+			WARN_ON_ONCE(s >= e);
+			kvm_arch_update_mem_attr(kvm, slot, attr, s, e);
+		}
+	}
+
+	return r;
+}
+EXPORT_SYMBOL_GPL(kvm_vm_set_mem_attr);
+
 #else /* !CONFIG_HAVE_KVM_RESTRICTED_MEM */
 
 static inline void kvm_restrictedmem_register(struct kvm_memory_slot *slot)