[PATCH 06/18] KVM: x86/mmu: Drop ignored return value from kvm_tdp_mmu_clear_dirty_slot()

Sean Christopherson
2024-10-11T02:11:05Z

Drop the return value from kvm_tdp_mmu_clear_dirty_slot() as its sole
caller ignores the result (KVM flushes after clearing dirty logs based on
the logs themselves, not based on SPTEs).

Cc: David Matlack <dmatlack@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
---
arch/x86/kvm/mmu/tdp_mmu.c | 20 ++++++--------------
arch/x86/kvm/mmu/tdp_mmu.h | 2 +-
2 files changed, 7 insertions(+), 15 deletions(-)

diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
index 91caa73a905b..9c66be7fb002 100644
--- a/arch/x86/kvm/mmu/tdp_mmu.c
+++ b/arch/x86/kvm/mmu/tdp_mmu.c
@@ -1492,13 +1492,12 @@ static bool tdp_mmu_need_write_protect(struct kvm_mmu_page *sp)
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)
+static void clear_dirty_gfn_range(struct kvm *kvm, struct kvm_mmu_page *root,
+ gfn_t start, gfn_t end)
{
const u64 dbit = tdp_mmu_need_write_protect(root) ? PT_WRITABLE_MASK :
shadow_dirty_mask;
struct tdp_iter iter;
- bool spte_set = false;

rcu_read_lock();

@@ -1519,31 +1518,24 @@ static bool clear_dirty_gfn_range(struct kvm *kvm, struct kvm_mmu_page *root,

if (tdp_mmu_set_spte_atomic(kvm, &iter, iter.old_spte & ~dbit))
goto retry;
-
- spte_set = true;
}

rcu_read_unlock();
- return spte_set;
}

/*
* 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.
+ * memslot.
*/
-bool kvm_tdp_mmu_clear_dirty_slot(struct kvm *kvm,
+void kvm_tdp_mmu_clear_dirty_slot(struct kvm *kvm,
const struct kvm_memory_slot *slot)
{
struct kvm_mmu_page *root;
- bool spte_set = false;

lockdep_assert_held_read(&kvm->mmu_lock);
for_each_valid_tdp_mmu_root_yield_safe(kvm, root, slot->as_id)
- spte_set |= clear_dirty_gfn_range(kvm, root, slot->base_gfn,
- slot->base_gfn + slot->npages);
-
- return spte_set;
+ clear_dirty_gfn_range(kvm, root, slot->base_gfn,
+ slot->base_gfn + slot->npages);
}

static void clear_dirty_pt_masked(struct kvm *kvm, struct kvm_mmu_page *root,
diff --git a/arch/x86/kvm/mmu/tdp_mmu.h b/arch/x86/kvm/mmu/tdp_mmu.h
index 1b74e058a81c..d842bfe103ab 100644
--- a/arch/x86/kvm/mmu/tdp_mmu.h
+++ b/arch/x86/kvm/mmu/tdp_mmu.h
@@ -34,7 +34,7 @@ bool kvm_tdp_mmu_test_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range);

bool kvm_tdp_mmu_wrprot_slot(struct kvm *kvm,
const struct kvm_memory_slot *slot, int min_level);
-bool kvm_tdp_mmu_clear_dirty_slot(struct kvm *kvm,
+void kvm_tdp_mmu_clear_dirty_slot(struct kvm *kvm,
const struct kvm_memory_slot *slot);
void kvm_tdp_mmu_clear_dirty_pt_masked(struct kvm *kvm,
struct kvm_memory_slot *slot,
--
2.47.0.rc1.288.g06298d1525-goog