For the logic, the function can be divided into two parts: one is adjusting
pte_access, the rest one is setting spte according the pte_access. It makes
the code more readable
Signed-off-by: Xiao Guangrong <xiaoguangr...@linux.vnet.ibm.com>
---
arch/x86/kvm/mmu.c | 51 ++++++++++++++++++++++++++-------------------------
1 files changed, 26 insertions(+), 25 deletions(-)
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index a999755..af8bcb2 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -2336,32 +2336,13 @@ static int set_spte(struct kvm_vcpu *vcpu, u64 *sptep,
return 0;
spte = PT_PRESENT_MASK;
- if (!speculative)
- spte |= shadow_accessed_mask;
-
- if (pte_access & ACC_EXEC_MASK)
- spte |= shadow_x_mask;
- else
- spte |= shadow_nx_mask;
-
- if (pte_access & ACC_USER_MASK)
- spte |= shadow_user_mask;
-
- if (level > PT_PAGE_TABLE_LEVEL)
- spte |= PT_PAGE_SIZE_MASK;
- if (tdp_enabled)
- spte |= kvm_x86_ops->get_mt_mask(vcpu, gfn,
- kvm_is_mmio_pfn(pfn));
if (host_writable)
spte |= SPTE_HOST_WRITEABLE;
else
pte_access &= ~ACC_WRITE_MASK;
- spte |= (u64)pfn << PAGE_SHIFT;
-
if (pte_access & ACC_WRITE_MASK) {
-
/*
* Other vcpu creates new sp in the window between
* mapping_level() and acquiring mmu-lock. We can
@@ -2369,11 +2350,9 @@ static int set_spte(struct kvm_vcpu *vcpu, u64 *sptep,
* be fixed if guest refault.
*/
if (level > PT_PAGE_TABLE_LEVEL &&
- has_wrprotected_page(vcpu->kvm, gfn, level))
+ has_wrprotected_page(vcpu->kvm, gfn, level))
goto done;
- spte |= PT_WRITABLE_MASK | SPTE_MMU_WRITEABLE;
-
/*
* Optimization: for pte sync, if spte was writable the hash
* lookup is unnecessary (and expensive). Write protection
@@ -2381,21 +2360,43 @@ static int set_spte(struct kvm_vcpu *vcpu, u64 *sptep,
* Same reasoning can be applied to dirty page accounting.
*/
if (!can_unsync && is_writable_pte(*sptep))
- goto set_pte;
+ goto out_access_adjust;
if (mmu_need_write_protect(vcpu, gfn, can_unsync)) {
pgprintk("%s: found shadow page for %llx, marking ro\n",
__func__, gfn);
ret = 1;
pte_access &= ~ACC_WRITE_MASK;
- spte &= ~(PT_WRITABLE_MASK | SPTE_MMU_WRITEABLE);
}
}
+out_access_adjust:
+ if (!speculative)
+ spte |= shadow_accessed_mask;
+
+ if (pte_access & ACC_EXEC_MASK)
+ spte |= shadow_x_mask;
+ else
+ spte |= shadow_nx_mask;
+
+ if (pte_access & ACC_USER_MASK)
+ spte |= shadow_user_mask;
+
if (pte_access & ACC_WRITE_MASK)
+ spte |= PT_WRITABLE_MASK | SPTE_MMU_WRITEABLE;
+
+ if (level > PT_PAGE_TABLE_LEVEL)
+ spte |= PT_PAGE_SIZE_MASK;
+
+ if (tdp_enabled)
+ spte |= kvm_x86_ops->get_mt_mask(vcpu, gfn,
+ kvm_is_mmio_pfn(pfn));
+
+ spte |= (u64)pfn << PAGE_SHIFT;
+
+ if (is_writable_pte(spte))
mark_page_dirty(vcpu->kvm, gfn);
-set_pte:
if (mmu_spte_update(sptep, spte))
kvm_flush_remote_tlbs(vcpu->kvm);
done:
--
1.7.7.6
--
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