KVM: x86/mmu: Open code leaf invalidation from mmu_notifier

The mmu_notifier path is a bit of a special snowflake, e.g. it zaps only a
single address space (because it's per-slot), and can't always yield.
Because of this, it calls kvm_tdp_mmu_zap_leafs() in ways that no one
else does.

Iterate manually over the leafs in response to an mmu_notifier
invalidation, instead of invoking kvm_tdp_mmu_zap_leafs().  Drop the
@can_yield param from kvm_tdp_mmu_zap_leafs() as its sole remaining
caller unconditionally passes "true".

Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20230916003916.2545000-2-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index e1d011c..59f5e40 100644 (file)
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -6260,7 +6260,7 @@ void kvm_zap_gfn_range(struct kvm *kvm, gfn_t gfn_start, gfn_t gfn_end)
        if (tdp_mmu_enabled) {
                for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++)
                        flush = kvm_tdp_mmu_zap_leafs(kvm, i, gfn_start,
-                                                     gfn_end, true, flush);
+                                                     gfn_end, flush);
        }
 
        if (flush)

diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
index 6c63f2d..9c08159 100644 (file)
--- a/arch/x86/kvm/mmu/tdp_mmu.c
+++ b/arch/x86/kvm/mmu/tdp_mmu.c
@@ -878,12 +878,12 @@ static bool tdp_mmu_zap_leafs(struct kvm *kvm, struct kvm_mmu_page *root,
  * more SPTEs were zapped since the MMU lock was last acquired.
  */
 bool kvm_tdp_mmu_zap_leafs(struct kvm *kvm, int as_id, gfn_t start, gfn_t end,
-                          bool can_yield, bool flush)
+                          bool flush)
 {
        struct kvm_mmu_page *root;
 
        for_each_tdp_mmu_root_yield_safe(kvm, root, as_id)
-               flush = tdp_mmu_zap_leafs(kvm, root, start, end, can_yield, flush);
+               flush = tdp_mmu_zap_leafs(kvm, root, start, end, true, flush);
 
        return flush;
 }
@@ -1146,8 +1146,13 @@ retry:
 bool kvm_tdp_mmu_unmap_gfn_range(struct kvm *kvm, struct kvm_gfn_range *range,
                                 bool flush)
 {
-       return kvm_tdp_mmu_zap_leafs(kvm, range->slot->as_id, range->start,
-                                    range->end, range->may_block, flush);
+       struct kvm_mmu_page *root;
+
+       for_each_tdp_mmu_root_yield_safe(kvm, root, range->slot->as_id)
+               flush = tdp_mmu_zap_leafs(kvm, root, range->start, range->end,
+                                         range->may_block, flush);
+
+       return flush;
 }
 
 typedef bool (*tdp_handler_t)(struct kvm *kvm, struct tdp_iter *iter,

diff --git a/arch/x86/kvm/mmu/tdp_mmu.h b/arch/x86/kvm/mmu/tdp_mmu.h
index 0a63b1a..eb4fa34 100644 (file)
--- a/arch/x86/kvm/mmu/tdp_mmu.h
+++ b/arch/x86/kvm/mmu/tdp_mmu.h
@@ -20,8 +20,8 @@ __must_check static inline bool kvm_tdp_mmu_get_root(struct kvm_mmu_page *root)
 void kvm_tdp_mmu_put_root(struct kvm *kvm, struct kvm_mmu_page *root,
                          bool shared);
 
-bool kvm_tdp_mmu_zap_leafs(struct kvm *kvm, int as_id, gfn_t start,
-                                gfn_t end, bool can_yield, bool flush);
+bool kvm_tdp_mmu_zap_leafs(struct kvm *kvm, int as_id, gfn_t start, gfn_t end,
+                          bool flush);
 bool kvm_tdp_mmu_zap_sp(struct kvm *kvm, struct kvm_mmu_page *sp);
 void kvm_tdp_mmu_zap_all(struct kvm *kvm);
 void kvm_tdp_mmu_invalidate_all_roots(struct kvm *kvm);