[PATCH v3 14/15] KVM: MMU: clean up spte_write_protect

Xiao Guangrong
2013-10-23T13:31:13Z

Now, the only user of spte_write_protect is rmap_write_protect which
always calls spte_write_protect with pt_protect = true, so drop
it and the unused parameter @kvm

Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
---
arch/x86/kvm/mmu.c | 19 ++++++++-----------
1 file changed, 8 insertions(+), 11 deletions(-)

diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index d82bbec..3e4b941 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -1340,8 +1340,7 @@ static void drop_large_spte(struct kvm_vcpu *vcpu, u64 *sptep)
}

/*
- * Write-protect on the specified @sptep, @pt_protect indicates whether
- * spte write-protection is caused by protecting shadow page table.
+ * Write-protect on the specified @sptep.
*
* Note: write protection is difference between drity logging and spte
* protection:
@@ -1352,25 +1351,23 @@ static void drop_large_spte(struct kvm_vcpu *vcpu, u64 *sptep)
*
* Return true if tlb need be flushed.
*/
-static bool spte_write_protect(struct kvm *kvm, u64 *sptep, bool pt_protect)
+static bool spte_write_protect(u64 *sptep)
{
u64 spte = *sptep;

if (!is_writable_pte(spte) &&
- !(pt_protect && spte_is_locklessly_modifiable(spte)))
+ !spte_is_locklessly_modifiable(spte))
return false;

rmap_printk("rmap_write_protect: spte %p %llx\n", sptep, *sptep);

- if (pt_protect)
- spte &= ~SPTE_MMU_WRITEABLE;
- spte = spte & ~PT_WRITABLE_MASK;
+ spte &= ~SPTE_MMU_WRITEABLE;
+ spte &= ~PT_WRITABLE_MASK;

return mmu_spte_update(sptep, spte);
}

-static bool __rmap_write_protect(struct kvm *kvm, unsigned long *rmapp,
- bool pt_protect)
+static bool __rmap_write_protect(unsigned long *rmapp)
{
u64 *sptep;
struct rmap_iterator iter;
@@ -1379,7 +1376,7 @@ static bool __rmap_write_protect(struct kvm *kvm, unsigned long *rmapp,
for (sptep = rmap_get_first(*rmapp, &iter); sptep;) {
BUG_ON(!(*sptep & PT_PRESENT_MASK));

- flush |= spte_write_protect(kvm, sptep, pt_protect);
+ flush |= spte_write_protect(sptep);
sptep = rmap_get_next(&iter);
}

@@ -1454,7 +1451,7 @@ static bool rmap_write_protect(struct kvm *kvm, u64 gfn)
for (i = PT_PAGE_TABLE_LEVEL;
i < PT_PAGE_TABLE_LEVEL + KVM_NR_PAGE_SIZES; ++i) {
rmapp = __gfn_to_rmap(gfn, i, slot);
- write_protected |= __rmap_write_protect(kvm, rmapp, true);
+ write_protected |= __rmap_write_protect(rmapp);
}

return write_protected;
--
1.8.1.4