Re: [PATCH v9 6/8] KVM: Update lpage info when private/shared memory are mixed
On Tue, Nov 08, 2022 at 08:08:05PM +0800, Yuan Yao wrote: > On Tue, Oct 25, 2022 at 11:13:42PM +0800, Chao Peng wrote: > > When private/shared memory are mixed in a large page, the lpage_info may > > not be accurate and should be updated with this mixed info. A large page > > has mixed pages can't be really mapped as large page since its > > private/shared pages are from different physical memory. > > > > Update lpage_info when private/shared memory attribute is changed. If > > both private and shared pages are within a large page region, it can't > > be mapped as large page. It's a bit challenge to track the mixed > > info in a 'count' like variable, this patch instead reserves a bit in > > 'disallow_lpage' to indicate a large page has mixed private/share pages. > > > > Signed-off-by: Chao Peng > > --- > > arch/x86/include/asm/kvm_host.h | 8 +++ > > arch/x86/kvm/mmu/mmu.c | 112 +++- > > arch/x86/kvm/x86.c | 2 + > > include/linux/kvm_host.h| 19 ++ > > virt/kvm/kvm_main.c | 16 +++-- > > 5 files changed, 152 insertions(+), 5 deletions(-) > > > > diff --git a/arch/x86/include/asm/kvm_host.h > > b/arch/x86/include/asm/kvm_host.h > > index 7551b6f9c31c..db811a54e3fd 100644 > > --- a/arch/x86/include/asm/kvm_host.h > > +++ b/arch/x86/include/asm/kvm_host.h > > @@ -37,6 +37,7 @@ > > #include > > > > #define __KVM_HAVE_ARCH_VCPU_DEBUGFS > > +#define __KVM_HAVE_ARCH_UPDATE_MEM_ATTR > > > > #define KVM_MAX_VCPUS 1024 > > > > @@ -952,6 +953,13 @@ struct kvm_vcpu_arch { > > #endif > > }; > > > > +/* > > + * Use a bit in disallow_lpage to indicate private/shared pages mixed at > > the > > + * level. The remaining bits are used as a reference count. > > + */ > > +#define KVM_LPAGE_PRIVATE_SHARED_MIXED (1U << 31) > > +#define KVM_LPAGE_COUNT_MAX((1U << 31) - 1) > > + > > struct kvm_lpage_info { > > int disallow_lpage; > > }; > > diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c > > index 33b1aec44fb8..67a9823a8c35 100644 > > --- a/arch/x86/kvm/mmu/mmu.c > > +++ b/arch/x86/kvm/mmu/mmu.c > > @@ -762,11 +762,16 @@ static void update_gfn_disallow_lpage_count(const > > struct kvm_memory_slot *slot, > > { > > struct kvm_lpage_info *linfo; > > int i; > > + int disallow_count; > > > > for (i = PG_LEVEL_2M; i <= KVM_MAX_HUGEPAGE_LEVEL; ++i) { > > linfo = lpage_info_slot(gfn, slot, i); > > + > > + disallow_count = linfo->disallow_lpage & KVM_LPAGE_COUNT_MAX; > > + WARN_ON(disallow_count + count < 0 || > > + disallow_count > KVM_LPAGE_COUNT_MAX - count); > > + > > linfo->disallow_lpage += count; > > - WARN_ON(linfo->disallow_lpage < 0); > > } > > } > > > > @@ -6910,3 +6915,108 @@ void kvm_mmu_pre_destroy_vm(struct kvm *kvm) > > if (kvm->arch.nx_lpage_recovery_thread) > > kthread_stop(kvm->arch.nx_lpage_recovery_thread); > > } > > + > > +static inline bool linfo_is_mixed(struct kvm_lpage_info *linfo) > > +{ > > + return linfo->disallow_lpage & KVM_LPAGE_PRIVATE_SHARED_MIXED; > > +} > > + > > +static inline void linfo_update_mixed(struct kvm_lpage_info *linfo, bool > > mixed) > > +{ > > + if (mixed) > > + linfo->disallow_lpage |= KVM_LPAGE_PRIVATE_SHARED_MIXED; > > + else > > + linfo->disallow_lpage &= ~KVM_LPAGE_PRIVATE_SHARED_MIXED; > > +} > > + > > +static bool mem_attr_is_mixed_2m(struct kvm *kvm, unsigned int attr, > > +gfn_t start, gfn_t end) > > +{ > > + XA_STATE(xas, >mem_attr_array, start); > > + gfn_t gfn = start; > > + void *entry; > > + bool shared = attr == KVM_MEM_ATTR_SHARED; > > + bool mixed = false; > > + > > + rcu_read_lock(); > > + entry = xas_load(); > > + while (gfn < end) { > > + if (xas_retry(, entry)) > > + continue; > > + > > + KVM_BUG_ON(gfn != xas.xa_index, kvm); > > + > > + if ((entry && !shared) || (!entry && shared)) { > > + mixed = true; > > + goto out; > > + } > > + > > + entry = xas_next(); > > + gfn++; > > + } > > +out: > > + rcu_read_unlock(); > > + return mixed; > > +} > > + > > +static bool mem_attr_is_mixed(struct kvm *kvm, struct kvm_memory_slot > > *slot, > > + int level, unsigned int attr, > > + gfn_t start, gfn_t end) > > +{ > > + unsigned long gfn; > > + void *entry; > > + > > + if (level == PG_LEVEL_2M) > > + return mem_attr_is_mixed_2m(kvm, attr, start, end); > > + > > + entry = xa_load(>mem_attr_array, start); > > + for (gfn = start; gfn < end; gfn += KVM_PAGES_PER_HPAGE(level - 1)) { > > + if (linfo_is_mixed(lpage_info_slot(gfn, slot, level - 1))) > > + return true; > > + if (xa_load(>mem_attr_array, gfn) != entry) > > +
Re: [PATCH v9 6/8] KVM: Update lpage info when private/shared memory are mixed
On Tue, Oct 25, 2022 at 11:13:42PM +0800, Chao Peng wrote: > When private/shared memory are mixed in a large page, the lpage_info may > not be accurate and should be updated with this mixed info. A large page > has mixed pages can't be really mapped as large page since its > private/shared pages are from different physical memory. > > Update lpage_info when private/shared memory attribute is changed. If > both private and shared pages are within a large page region, it can't > be mapped as large page. It's a bit challenge to track the mixed > info in a 'count' like variable, this patch instead reserves a bit in > 'disallow_lpage' to indicate a large page has mixed private/share pages. > > Signed-off-by: Chao Peng > --- > arch/x86/include/asm/kvm_host.h | 8 +++ > arch/x86/kvm/mmu/mmu.c | 112 +++- > arch/x86/kvm/x86.c | 2 + > include/linux/kvm_host.h| 19 ++ > virt/kvm/kvm_main.c | 16 +++-- > 5 files changed, 152 insertions(+), 5 deletions(-) > > diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h > index 7551b6f9c31c..db811a54e3fd 100644 > --- a/arch/x86/include/asm/kvm_host.h > +++ b/arch/x86/include/asm/kvm_host.h > @@ -37,6 +37,7 @@ > #include > > #define __KVM_HAVE_ARCH_VCPU_DEBUGFS > +#define __KVM_HAVE_ARCH_UPDATE_MEM_ATTR > > #define KVM_MAX_VCPUS 1024 > > @@ -952,6 +953,13 @@ struct kvm_vcpu_arch { > #endif > }; > > +/* > + * Use a bit in disallow_lpage to indicate private/shared pages mixed at the > + * level. The remaining bits are used as a reference count. > + */ > +#define KVM_LPAGE_PRIVATE_SHARED_MIXED (1U << 31) > +#define KVM_LPAGE_COUNT_MAX ((1U << 31) - 1) > + > struct kvm_lpage_info { > int disallow_lpage; > }; > diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c > index 33b1aec44fb8..67a9823a8c35 100644 > --- a/arch/x86/kvm/mmu/mmu.c > +++ b/arch/x86/kvm/mmu/mmu.c > @@ -762,11 +762,16 @@ static void update_gfn_disallow_lpage_count(const > struct kvm_memory_slot *slot, > { > struct kvm_lpage_info *linfo; > int i; > + int disallow_count; > > for (i = PG_LEVEL_2M; i <= KVM_MAX_HUGEPAGE_LEVEL; ++i) { > linfo = lpage_info_slot(gfn, slot, i); > + > + disallow_count = linfo->disallow_lpage & KVM_LPAGE_COUNT_MAX; > + WARN_ON(disallow_count + count < 0 || > + disallow_count > KVM_LPAGE_COUNT_MAX - count); > + > linfo->disallow_lpage += count; > - WARN_ON(linfo->disallow_lpage < 0); > } > } > > @@ -6910,3 +6915,108 @@ void kvm_mmu_pre_destroy_vm(struct kvm *kvm) > if (kvm->arch.nx_lpage_recovery_thread) > kthread_stop(kvm->arch.nx_lpage_recovery_thread); > } > + > +static inline bool linfo_is_mixed(struct kvm_lpage_info *linfo) > +{ > + return linfo->disallow_lpage & KVM_LPAGE_PRIVATE_SHARED_MIXED; > +} > + > +static inline void linfo_update_mixed(struct kvm_lpage_info *linfo, bool > mixed) > +{ > + if (mixed) > + linfo->disallow_lpage |= KVM_LPAGE_PRIVATE_SHARED_MIXED; > + else > + linfo->disallow_lpage &= ~KVM_LPAGE_PRIVATE_SHARED_MIXED; > +} > + > +static bool mem_attr_is_mixed_2m(struct kvm *kvm, unsigned int attr, > + gfn_t start, gfn_t end) > +{ > + XA_STATE(xas, >mem_attr_array, start); > + gfn_t gfn = start; > + void *entry; > + bool shared = attr == KVM_MEM_ATTR_SHARED; > + bool mixed = false; > + > + rcu_read_lock(); > + entry = xas_load(); > + while (gfn < end) { > + if (xas_retry(, entry)) > + continue; > + > + KVM_BUG_ON(gfn != xas.xa_index, kvm); > + > + if ((entry && !shared) || (!entry && shared)) { > + mixed = true; > + goto out; > + } > + > + entry = xas_next(); > + gfn++; > + } > +out: > + rcu_read_unlock(); > + return mixed; > +} > + > +static bool mem_attr_is_mixed(struct kvm *kvm, struct kvm_memory_slot *slot, > + int level, unsigned int attr, > + gfn_t start, gfn_t end) > +{ > + unsigned long gfn; > + void *entry; > + > + if (level == PG_LEVEL_2M) > + return mem_attr_is_mixed_2m(kvm, attr, start, end); > + > + entry = xa_load(>mem_attr_array, start); > + for (gfn = start; gfn < end; gfn += KVM_PAGES_PER_HPAGE(level - 1)) { > + if (linfo_is_mixed(lpage_info_slot(gfn, slot, level - 1))) > + return true; > + if (xa_load(>mem_attr_array, gfn) != entry) > + return true; > + } > + return false; > +} > + > +void kvm_arch_update_mem_attr(struct kvm *kvm, struct kvm_memory_slot *slot, > + unsigned int attr, gfn_t start, gfn_t end) > +{ > + > + unsigned long
Re: [PATCH v9 6/8] KVM: Update lpage info when private/shared memory are mixed
On Wed, Oct 26, 2022 at 01:46:20PM -0700, Isaku Yamahata wrote: > On Tue, Oct 25, 2022 at 11:13:42PM +0800, > Chao Peng wrote: > > > When private/shared memory are mixed in a large page, the lpage_info may > > not be accurate and should be updated with this mixed info. A large page > > has mixed pages can't be really mapped as large page since its > > private/shared pages are from different physical memory. > > > > Update lpage_info when private/shared memory attribute is changed. If > > both private and shared pages are within a large page region, it can't > > be mapped as large page. It's a bit challenge to track the mixed > > info in a 'count' like variable, this patch instead reserves a bit in > > 'disallow_lpage' to indicate a large page has mixed private/share pages. > > > > Signed-off-by: Chao Peng > > --- > > arch/x86/include/asm/kvm_host.h | 8 +++ > > arch/x86/kvm/mmu/mmu.c | 112 +++- > > arch/x86/kvm/x86.c | 2 + > > include/linux/kvm_host.h| 19 ++ > > virt/kvm/kvm_main.c | 16 +++-- > > 5 files changed, 152 insertions(+), 5 deletions(-) > > > ... > > diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c > > index 33b1aec44fb8..67a9823a8c35 100644 > > --- a/arch/x86/kvm/mmu/mmu.c > > +++ b/arch/x86/kvm/mmu/mmu.c > ... > > @@ -6910,3 +6915,108 @@ void kvm_mmu_pre_destroy_vm(struct kvm *kvm) > > if (kvm->arch.nx_lpage_recovery_thread) > > kthread_stop(kvm->arch.nx_lpage_recovery_thread); > > } > > + > > +static inline bool linfo_is_mixed(struct kvm_lpage_info *linfo) > > +{ > > + return linfo->disallow_lpage & KVM_LPAGE_PRIVATE_SHARED_MIXED; > > +} > > + > > +static inline void linfo_update_mixed(struct kvm_lpage_info *linfo, bool > > mixed) > > +{ > > + if (mixed) > > + linfo->disallow_lpage |= KVM_LPAGE_PRIVATE_SHARED_MIXED; > > + else > > + linfo->disallow_lpage &= ~KVM_LPAGE_PRIVATE_SHARED_MIXED; > > +} > > + > > +static bool mem_attr_is_mixed_2m(struct kvm *kvm, unsigned int attr, > > +gfn_t start, gfn_t end) > > +{ > > + XA_STATE(xas, >mem_attr_array, start); > > + gfn_t gfn = start; > > + void *entry; > > + bool shared = attr == KVM_MEM_ATTR_SHARED; > > + bool mixed = false; > > + > > + rcu_read_lock(); > > + entry = xas_load(); > > + while (gfn < end) { > > + if (xas_retry(, entry)) > > + continue; > > + > > + KVM_BUG_ON(gfn != xas.xa_index, kvm); > > + > > + if ((entry && !shared) || (!entry && shared)) { > > + mixed = true; > > + goto out; > > nitpick: goto isn't needed. break should work. Thanks. > > > + } > > + > > + entry = xas_next(); > > + gfn++; > > + } > > +out: > > + rcu_read_unlock(); > > + return mixed; > > +} > > + > > +static bool mem_attr_is_mixed(struct kvm *kvm, struct kvm_memory_slot > > *slot, > > + int level, unsigned int attr, > > + gfn_t start, gfn_t end) > > +{ > > + unsigned long gfn; > > + void *entry; > > + > > + if (level == PG_LEVEL_2M) > > + return mem_attr_is_mixed_2m(kvm, attr, start, end); > > + > > + entry = xa_load(>mem_attr_array, start); > > + for (gfn = start; gfn < end; gfn += KVM_PAGES_PER_HPAGE(level - 1)) { > > + if (linfo_is_mixed(lpage_info_slot(gfn, slot, level - 1))) > > + return true; > > + if (xa_load(>mem_attr_array, gfn) != entry) > > + return true; > > + } > > + return false; > > +} > > + > > +void kvm_arch_update_mem_attr(struct kvm *kvm, struct kvm_memory_slot > > *slot, > > + unsigned int attr, gfn_t start, gfn_t end) > > +{ > > + > > + unsigned long lpage_start, lpage_end; > > + unsigned long gfn, pages, mask; > > + int level; > > + > > + WARN_ONCE(!(attr & (KVM_MEM_ATTR_PRIVATE | KVM_MEM_ATTR_SHARED)), > > + "Unsupported mem attribute.\n"); > > + > > + /* > > +* The sequence matters here: we update the higher level basing on the > > +* lower level's scanning result. > > +*/ > > + for (level = PG_LEVEL_2M; level <= KVM_MAX_HUGEPAGE_LEVEL; level++) { > > + pages = KVM_PAGES_PER_HPAGE(level); > > + mask = ~(pages - 1); > > nitpick: KVM_HPAGE_MASK(level). Maybe matter of preference. Yes, haven't noticed there is a KVM_HPAGE_MASK defined. Have no strong preference here, since I already have KVM_PAGES_PER_HPAGE(level), getting mask is straightforward. A single KVM_HPAGE_MASK(level) will not give me what I need since here is gfn, KVM_HPAGE_MASK(level)>> PAGE_SHIFT should be the right equivalent. Chao > > > > + lpage_start = max(start & mask, slot->base_gfn); > > + lpage_end = (end - 1) & mask; > > + > > + /* > > +* We only need to scan the head and tail page, for middle pages > >
Re: [PATCH v9 6/8] KVM: Update lpage info when private/shared memory are mixed
On Tue, Oct 25, 2022 at 11:13:42PM +0800, Chao Peng wrote: > When private/shared memory are mixed in a large page, the lpage_info may > not be accurate and should be updated with this mixed info. A large page > has mixed pages can't be really mapped as large page since its > private/shared pages are from different physical memory. > > Update lpage_info when private/shared memory attribute is changed. If > both private and shared pages are within a large page region, it can't > be mapped as large page. It's a bit challenge to track the mixed > info in a 'count' like variable, this patch instead reserves a bit in > 'disallow_lpage' to indicate a large page has mixed private/share pages. > > Signed-off-by: Chao Peng > --- > arch/x86/include/asm/kvm_host.h | 8 +++ > arch/x86/kvm/mmu/mmu.c | 112 +++- > arch/x86/kvm/x86.c | 2 + > include/linux/kvm_host.h| 19 ++ > virt/kvm/kvm_main.c | 16 +++-- > 5 files changed, 152 insertions(+), 5 deletions(-) > ... > diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c > index 33b1aec44fb8..67a9823a8c35 100644 > --- a/arch/x86/kvm/mmu/mmu.c > +++ b/arch/x86/kvm/mmu/mmu.c ... > @@ -6910,3 +6915,108 @@ void kvm_mmu_pre_destroy_vm(struct kvm *kvm) > if (kvm->arch.nx_lpage_recovery_thread) > kthread_stop(kvm->arch.nx_lpage_recovery_thread); > } > + > +static inline bool linfo_is_mixed(struct kvm_lpage_info *linfo) > +{ > + return linfo->disallow_lpage & KVM_LPAGE_PRIVATE_SHARED_MIXED; > +} > + > +static inline void linfo_update_mixed(struct kvm_lpage_info *linfo, bool > mixed) > +{ > + if (mixed) > + linfo->disallow_lpage |= KVM_LPAGE_PRIVATE_SHARED_MIXED; > + else > + linfo->disallow_lpage &= ~KVM_LPAGE_PRIVATE_SHARED_MIXED; > +} > + > +static bool mem_attr_is_mixed_2m(struct kvm *kvm, unsigned int attr, > + gfn_t start, gfn_t end) > +{ > + XA_STATE(xas, >mem_attr_array, start); > + gfn_t gfn = start; > + void *entry; > + bool shared = attr == KVM_MEM_ATTR_SHARED; > + bool mixed = false; > + > + rcu_read_lock(); > + entry = xas_load(); > + while (gfn < end) { > + if (xas_retry(, entry)) > + continue; > + > + KVM_BUG_ON(gfn != xas.xa_index, kvm); > + > + if ((entry && !shared) || (!entry && shared)) { > + mixed = true; > + goto out; nitpick: goto isn't needed. break should work. > + } > + > + entry = xas_next(); > + gfn++; > + } > +out: > + rcu_read_unlock(); > + return mixed; > +} > + > +static bool mem_attr_is_mixed(struct kvm *kvm, struct kvm_memory_slot *slot, > + int level, unsigned int attr, > + gfn_t start, gfn_t end) > +{ > + unsigned long gfn; > + void *entry; > + > + if (level == PG_LEVEL_2M) > + return mem_attr_is_mixed_2m(kvm, attr, start, end); > + > + entry = xa_load(>mem_attr_array, start); > + for (gfn = start; gfn < end; gfn += KVM_PAGES_PER_HPAGE(level - 1)) { > + if (linfo_is_mixed(lpage_info_slot(gfn, slot, level - 1))) > + return true; > + if (xa_load(>mem_attr_array, gfn) != entry) > + return true; > + } > + return false; > +} > + > +void kvm_arch_update_mem_attr(struct kvm *kvm, struct kvm_memory_slot *slot, > + unsigned int attr, gfn_t start, gfn_t end) > +{ > + > + unsigned long lpage_start, lpage_end; > + unsigned long gfn, pages, mask; > + int level; > + > + WARN_ONCE(!(attr & (KVM_MEM_ATTR_PRIVATE | KVM_MEM_ATTR_SHARED)), > + "Unsupported mem attribute.\n"); > + > + /* > + * The sequence matters here: we update the higher level basing on the > + * lower level's scanning result. > + */ > + for (level = PG_LEVEL_2M; level <= KVM_MAX_HUGEPAGE_LEVEL; level++) { > + pages = KVM_PAGES_PER_HPAGE(level); > + mask = ~(pages - 1); nitpick: KVM_HPAGE_MASK(level). Maybe matter of preference. > + lpage_start = max(start & mask, slot->base_gfn); > + lpage_end = (end - 1) & mask; > + > + /* > + * We only need to scan the head and tail page, for middle pages > + * we know they are not mixed. > + */ > + linfo_update_mixed(lpage_info_slot(lpage_start, slot, level), > +mem_attr_is_mixed(kvm, slot, level, attr, > + lpage_start, start)); > + > + if (lpage_start == lpage_end) > + return; > + > + for (gfn = lpage_start + pages; gfn < lpage_end; gfn += pages) > + linfo_update_mixed(lpage_info_slot(gfn, slot, level), > +
[PATCH v9 6/8] KVM: Update lpage info when private/shared memory are mixed
When private/shared memory are mixed in a large page, the lpage_info may not be accurate and should be updated with this mixed info. A large page has mixed pages can't be really mapped as large page since its private/shared pages are from different physical memory. Update lpage_info when private/shared memory attribute is changed. If both private and shared pages are within a large page region, it can't be mapped as large page. It's a bit challenge to track the mixed info in a 'count' like variable, this patch instead reserves a bit in 'disallow_lpage' to indicate a large page has mixed private/share pages. Signed-off-by: Chao Peng --- arch/x86/include/asm/kvm_host.h | 8 +++ arch/x86/kvm/mmu/mmu.c | 112 +++- arch/x86/kvm/x86.c | 2 + include/linux/kvm_host.h| 19 ++ virt/kvm/kvm_main.c | 16 +++-- 5 files changed, 152 insertions(+), 5 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 7551b6f9c31c..db811a54e3fd 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -37,6 +37,7 @@ #include #define __KVM_HAVE_ARCH_VCPU_DEBUGFS +#define __KVM_HAVE_ARCH_UPDATE_MEM_ATTR #define KVM_MAX_VCPUS 1024 @@ -952,6 +953,13 @@ struct kvm_vcpu_arch { #endif }; +/* + * Use a bit in disallow_lpage to indicate private/shared pages mixed at the + * level. The remaining bits are used as a reference count. + */ +#define KVM_LPAGE_PRIVATE_SHARED_MIXED (1U << 31) +#define KVM_LPAGE_COUNT_MAX((1U << 31) - 1) + struct kvm_lpage_info { int disallow_lpage; }; diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 33b1aec44fb8..67a9823a8c35 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -762,11 +762,16 @@ static void update_gfn_disallow_lpage_count(const struct kvm_memory_slot *slot, { struct kvm_lpage_info *linfo; int i; + int disallow_count; for (i = PG_LEVEL_2M; i <= KVM_MAX_HUGEPAGE_LEVEL; ++i) { linfo = lpage_info_slot(gfn, slot, i); + + disallow_count = linfo->disallow_lpage & KVM_LPAGE_COUNT_MAX; + WARN_ON(disallow_count + count < 0 || + disallow_count > KVM_LPAGE_COUNT_MAX - count); + linfo->disallow_lpage += count; - WARN_ON(linfo->disallow_lpage < 0); } } @@ -6910,3 +6915,108 @@ void kvm_mmu_pre_destroy_vm(struct kvm *kvm) if (kvm->arch.nx_lpage_recovery_thread) kthread_stop(kvm->arch.nx_lpage_recovery_thread); } + +static inline bool linfo_is_mixed(struct kvm_lpage_info *linfo) +{ + return linfo->disallow_lpage & KVM_LPAGE_PRIVATE_SHARED_MIXED; +} + +static inline void linfo_update_mixed(struct kvm_lpage_info *linfo, bool mixed) +{ + if (mixed) + linfo->disallow_lpage |= KVM_LPAGE_PRIVATE_SHARED_MIXED; + else + linfo->disallow_lpage &= ~KVM_LPAGE_PRIVATE_SHARED_MIXED; +} + +static bool mem_attr_is_mixed_2m(struct kvm *kvm, unsigned int attr, +gfn_t start, gfn_t end) +{ + XA_STATE(xas, >mem_attr_array, start); + gfn_t gfn = start; + void *entry; + bool shared = attr == KVM_MEM_ATTR_SHARED; + bool mixed = false; + + rcu_read_lock(); + entry = xas_load(); + while (gfn < end) { + if (xas_retry(, entry)) + continue; + + KVM_BUG_ON(gfn != xas.xa_index, kvm); + + if ((entry && !shared) || (!entry && shared)) { + mixed = true; + goto out; + } + + entry = xas_next(); + gfn++; + } +out: + rcu_read_unlock(); + return mixed; +} + +static bool mem_attr_is_mixed(struct kvm *kvm, struct kvm_memory_slot *slot, + int level, unsigned int attr, + gfn_t start, gfn_t end) +{ + unsigned long gfn; + void *entry; + + if (level == PG_LEVEL_2M) + return mem_attr_is_mixed_2m(kvm, attr, start, end); + + entry = xa_load(>mem_attr_array, start); + for (gfn = start; gfn < end; gfn += KVM_PAGES_PER_HPAGE(level - 1)) { + if (linfo_is_mixed(lpage_info_slot(gfn, slot, level - 1))) + return true; + if (xa_load(>mem_attr_array, gfn) != entry) + return true; + } + return false; +} + +void kvm_arch_update_mem_attr(struct kvm *kvm, struct kvm_memory_slot *slot, + unsigned int attr, gfn_t start, gfn_t end) +{ + + unsigned long lpage_start, lpage_end; + unsigned long gfn, pages, mask; + int level; + + WARN_ONCE(!(attr & (KVM_MEM_ATTR_PRIVATE | KVM_MEM_ATTR_SHARED)), + "Unsupported mem attribute.\n"); + + /* +