KVM_PAGES_PER_HPAGE is got by left shift (KVM_HPAGE_GFN_SHIFT + PAGE_SHIFT)
and then divide by PAGE_SIZE, which could be simplified by just left shift
KVM_HPAGE_GFN_SHIFT.
At the same time, in almost 40% places where KVM_PAGES_PER_HPAGE is used,
pfn mask is actually what it needs instead of the number of pages.
This patch replaces KVM_PAGES_PER_HPAGE with KVM_HPAGE_GFN_SIZE and
introduces KVM_HPAGE_GFN_MASK to make it a little bit easy to read.
Signed-off-by: Wei Yang <richard.weiyang@xxxxxxxxx>
---
arch/x86/include/asm/kvm_host.h | 3 ++-
arch/x86/kvm/mmu.c | 10 +++++-----
arch/x86/kvm/paging_tmpl.h | 6 +++---
arch/x86/kvm/x86.c | 6 +++---
4 files changed, 13 insertions(+), 12 deletions(-)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index f1a4e520ef5c..c5e7bb811b1e 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -104,10 +104,11 @@
/* KVM Hugepage definitions for x86 */
#define KVM_NR_PAGE_SIZES 3
#define KVM_HPAGE_GFN_SHIFT(x) (((x) - 1) * 9)
+#define KVM_HPAGE_GFN_SIZE(x) (1UL << KVM_HPAGE_GFN_SHIFT(x))
+#define KVM_HPAGE_GFN_MASK(x) (~(KVM_HPAGE_GFN_SIZE(x) - 1))
#define KVM_HPAGE_SHIFT(x) (PAGE_SHIFT + KVM_HPAGE_GFN_SHIFT(x))
#define KVM_HPAGE_SIZE(x) (1UL << KVM_HPAGE_SHIFT(x))
#define KVM_HPAGE_MASK(x) (~(KVM_HPAGE_SIZE(x) - 1))
-#define KVM_PAGES_PER_HPAGE(x) (KVM_HPAGE_SIZE(x) / PAGE_SIZE)
static inline gfn_t gfn_to_index(gfn_t gfn, gfn_t base_gfn, int level)
{
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 0caaaa25e88b..897614414311 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -3170,7 +3170,7 @@ static void transparent_hugepage_adjust(struct kvm_vcpu *vcpu,
* head.
*/
*levelp = level = PT_DIRECTORY_LEVEL;
- mask = KVM_PAGES_PER_HPAGE(level) - 1;
+ mask = KVM_HPAGE_GFN_SIZE(level) - 1;
VM_BUG_ON((gfn & mask) != (pfn & mask));
if (pfn & mask) {
gfn &= ~mask;
@@ -3416,7 +3416,7 @@ static int nonpaging_map(struct kvm_vcpu *vcpu, gva_t v, u32 error_code,
if (level > PT_DIRECTORY_LEVEL)
level = PT_DIRECTORY_LEVEL;
- gfn &= ~(KVM_PAGES_PER_HPAGE(level) - 1);
+ gfn &= KVM_HPAGE_GFN_MASK(level);
}
if (fast_page_fault(vcpu, v, level, error_code))
@@ -4018,9 +4018,9 @@ EXPORT_SYMBOL_GPL(kvm_handle_page_fault);
static bool
check_hugepage_cache_consistency(struct kvm_vcpu *vcpu, gfn_t gfn, int level)
{
- int page_num = KVM_PAGES_PER_HPAGE(level);
+ int page_num = KVM_HPAGE_GFN_SIZE(level);
- gfn &= ~(page_num - 1);
+ gfn &= KVM_HPAGE_GFN_MASK(level);
return kvm_mtrr_check_gfn_range_consistency(vcpu, gfn, page_num);
}
@@ -4053,7 +4053,7 @@ static int tdp_page_fault(struct kvm_vcpu *vcpu, gva_t gpa, u32 error_code,
if (level > PT_DIRECTORY_LEVEL &&
!check_hugepage_cache_consistency(vcpu, gfn, level))
level = PT_DIRECTORY_LEVEL;
- gfn &= ~(KVM_PAGES_PER_HPAGE(level) - 1);
+ gfn &= KVM_HPAGE_GFN_MASK(level);
}
if (fast_page_fault(vcpu, gpa, level, error_code))
diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h
index 14ffd973df54..c8a242715cbb 100644
--- a/arch/x86/kvm/paging_tmpl.h
+++ b/arch/x86/kvm/paging_tmpl.h
@@ -658,7 +658,7 @@ static int FNAME(fetch)(struct kvm_vcpu *vcpu, gva_t addr,
if (is_shadow_present_pte(*it.sptep))
continue;
- direct_gfn = gw->gfn & ~(KVM_PAGES_PER_HPAGE(it.level) - 1);
+ direct_gfn = gw->gfn & KVM_HPAGE_GFN_MASK(it.level);
sp = kvm_mmu_get_page(vcpu, direct_gfn, addr, it.level-1,
true, direct_access);
@@ -700,7 +700,7 @@ FNAME(is_self_change_mapping)(struct kvm_vcpu *vcpu,
bool *write_fault_to_shadow_pgtable)
{
int level;
- gfn_t mask = ~(KVM_PAGES_PER_HPAGE(walker->level) - 1);
+ gfn_t mask = KVM_HPAGE_GFN_MASK(walker->level);
bool self_changed = false;
if (!(walker->pte_access & ACC_WRITE_MASK ||
@@ -786,7 +786,7 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr, u32 error_code,
level = mapping_level(vcpu, walker.gfn, &force_pt_level);
if (likely(!force_pt_level)) {
level = min(walker.level, level);
- walker.gfn = walker.gfn & ~(KVM_PAGES_PER_HPAGE(level) - 1);
+ walker.gfn = walker.gfn & KVM_HPAGE_GFN_MASK(level);
}
} else
force_pt_level = true;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index f7dff0457846..70b4e5e74f7d 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -9021,9 +9021,9 @@ int kvm_arch_create_memslot(struct kvm *kvm, struct kvm_memory_slot *slot,
slot->arch.lpage_info[i - 1] = linfo;
- if (slot->base_gfn & (KVM_PAGES_PER_HPAGE(level) - 1))
+ if (slot->base_gfn & (KVM_HPAGE_GFN_SIZE(level) - 1))
linfo[0].disallow_lpage = 1;
- if ((slot->base_gfn + npages) & (KVM_PAGES_PER_HPAGE(level) - 1))
+ if ((slot->base_gfn + npages) & (KVM_HPAGE_GFN_SIZE(level) - 1))
linfo[lpages - 1].disallow_lpage = 1;
ugfn = slot->userspace_addr >> PAGE_SHIFT;
/*
@@ -9031,7 +9031,7 @@ int kvm_arch_create_memslot(struct kvm *kvm, struct kvm_memory_slot *slot,
* other, or if explicitly asked to, disable large page
* support for this slot
*/
- if ((slot->base_gfn ^ ugfn) & (KVM_PAGES_PER_HPAGE(level) - 1) ||
+ if ((slot->base_gfn ^ ugfn) & (KVM_HPAGE_GFN_SIZE(level) - 1) ||
!kvm_largepages_enabled()) {
unsigned long j;
--
2.15.1
