aboutsummaryrefslogtreecommitdiffstats
path: root/arch/x86/kvm/mmu/tdp_mmu.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/x86/kvm/mmu/tdp_mmu.c')
-rw-r--r--arch/x86/kvm/mmu/tdp_mmu.c51
1 files changed, 22 insertions, 29 deletions
diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
index d078157e62aa4..04c1f0957fea8 100644
--- a/arch/x86/kvm/mmu/tdp_mmu.c
+++ b/arch/x86/kvm/mmu/tdp_mmu.c
@@ -1548,17 +1548,21 @@ void kvm_tdp_mmu_try_split_huge_pages(struct kvm *kvm,
}
}
-/*
- * Clear the dirty status of all the SPTEs mapping GFNs in the memslot. If
- * AD bits are enabled, this will involve clearing the dirty bit on each SPTE.
- * If AD bits are not enabled, this will require clearing the writable bit on
- * each SPTE. Returns true if an SPTE has been changed and the TLBs need to
- * be flushed.
- */
+static bool tdp_mmu_need_write_protect(struct kvm_mmu_page *sp)
+{
+ /*
+ * All TDP MMU shadow pages share the same role as their root, aside
+ * from level, so it is valid to key off any shadow page to determine if
+ * write protection is needed for an entire tree.
+ */
+ return kvm_mmu_page_ad_need_write_protect(sp) || !kvm_ad_enabled();
+}
+
static bool clear_dirty_gfn_range(struct kvm *kvm, struct kvm_mmu_page *root,
gfn_t start, gfn_t end)
{
- u64 dbit = kvm_ad_enabled() ? shadow_dirty_mask : PT_WRITABLE_MASK;
+ const u64 dbit = tdp_mmu_need_write_protect(root) ? PT_WRITABLE_MASK :
+ shadow_dirty_mask;
struct tdp_iter iter;
bool spte_set = false;
@@ -1573,7 +1577,7 @@ retry:
if (tdp_mmu_iter_cond_resched(kvm, &iter, false, true))
continue;
- KVM_MMU_WARN_ON(kvm_ad_enabled() &&
+ KVM_MMU_WARN_ON(dbit == shadow_dirty_mask &&
spte_ad_need_write_protect(iter.old_spte));
if (!(iter.old_spte & dbit))
@@ -1590,11 +1594,9 @@ retry:
}
/*
- * Clear the dirty status of all the SPTEs mapping GFNs in the memslot. If
- * AD bits are enabled, this will involve clearing the dirty bit on each SPTE.
- * If AD bits are not enabled, this will require clearing the writable bit on
- * each SPTE. Returns true if an SPTE has been changed and the TLBs need to
- * be flushed.
+ * Clear the dirty status (D-bit or W-bit) of all the SPTEs mapping GFNs in the
+ * memslot. Returns true if an SPTE has been changed and the TLBs need to be
+ * flushed.
*/
bool kvm_tdp_mmu_clear_dirty_slot(struct kvm *kvm,
const struct kvm_memory_slot *slot)
@@ -1610,18 +1612,11 @@ bool kvm_tdp_mmu_clear_dirty_slot(struct kvm *kvm,
return spte_set;
}
-/*
- * Clears the dirty status of all the 4k SPTEs mapping GFNs for which a bit is
- * set in mask, starting at gfn. The given memslot is expected to contain all
- * the GFNs represented by set bits in the mask. If AD bits are enabled,
- * clearing the dirty status will involve clearing the dirty bit on each SPTE
- * or, if AD bits are not enabled, clearing the writable bit on each SPTE.
- */
static void clear_dirty_pt_masked(struct kvm *kvm, struct kvm_mmu_page *root,
gfn_t gfn, unsigned long mask, bool wrprot)
{
- u64 dbit = (wrprot || !kvm_ad_enabled()) ? PT_WRITABLE_MASK :
- shadow_dirty_mask;
+ const u64 dbit = (wrprot || tdp_mmu_need_write_protect(root)) ? PT_WRITABLE_MASK :
+ shadow_dirty_mask;
struct tdp_iter iter;
lockdep_assert_held_write(&kvm->mmu_lock);
@@ -1633,7 +1628,7 @@ static void clear_dirty_pt_masked(struct kvm *kvm, struct kvm_mmu_page *root,
if (!mask)
break;
- KVM_MMU_WARN_ON(kvm_ad_enabled() &&
+ KVM_MMU_WARN_ON(dbit == shadow_dirty_mask &&
spte_ad_need_write_protect(iter.old_spte));
if (iter.level > PG_LEVEL_4K ||
@@ -1659,11 +1654,9 @@ static void clear_dirty_pt_masked(struct kvm *kvm, struct kvm_mmu_page *root,
}
/*
- * Clears the dirty status of all the 4k SPTEs mapping GFNs for which a bit is
- * set in mask, starting at gfn. The given memslot is expected to contain all
- * the GFNs represented by set bits in the mask. If AD bits are enabled,
- * clearing the dirty status will involve clearing the dirty bit on each SPTE
- * or, if AD bits are not enabled, clearing the writable bit on each SPTE.
+ * Clear the dirty status (D-bit or W-bit) of all the 4k SPTEs mapping GFNs for
+ * which a bit is set in mask, starting at gfn. The given memslot is expected to
+ * contain all the GFNs represented by set bits in the mask.
*/
void kvm_tdp_mmu_clear_dirty_pt_masked(struct kvm *kvm,
struct kvm_memory_slot *slot,