[v13,44/85] KVM: x86/mmu: Convert page fault paths to kvm_faultin_pfn()

Commit Message

Sean Christopherson Oct. 10, 2024, 6:23 p.m. UTC

Convert KVM x86 to use the recently introduced __kvm_faultin_pfn().
Opportunstically capture the refcounted_page grabbed by KVM for use in
future changes.

No functional change intended.

Tested-by: Alex Bennée <[e-mail]>
Signed-off-by: Sean Christopherson <[e-mail]>
---
 arch/x86/kvm/mmu/mmu.c          | 14 ++++++++++----
 arch/x86/kvm/mmu/mmu_internal.h |  1 +
 2 files changed, 11 insertions(+), 4 deletions(-)

Patch

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index f730870887dd..2e2076287aaf 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -4416,11 +4416,14 @@  static int kvm_mmu_faultin_pfn_private(struct kvm_vcpu *vcpu,
 static int __kvm_mmu_faultin_pfn(struct kvm_vcpu *vcpu,
 				 struct kvm_page_fault *fault)
 {
+	unsigned int foll = fault->write ? FOLL_WRITE : 0;
+
 	if (fault->is_private)
 		return kvm_mmu_faultin_pfn_private(vcpu, fault);
 
-	fault->pfn = __gfn_to_pfn_memslot(fault->slot, fault->gfn, false, true,
-					  fault->write, &fault->map_writable);
+	foll |= FOLL_NOWAIT;
+	fault->pfn = __kvm_faultin_pfn(fault->slot, fault->gfn, foll,
+				       &fault->map_writable, &fault->refcounted_page);
 
 	/*
 	 * If resolving the page failed because I/O is needed to fault-in the
@@ -4447,8 +4450,11 @@  static int __kvm_mmu_faultin_pfn(struct kvm_vcpu *vcpu,
 	 * to wait for IO.  Note, gup always bails if it is unable to quickly
 	 * get a page and a fatal signal, i.e. SIGKILL, is pending.
 	 */
-	fault->pfn = __gfn_to_pfn_memslot(fault->slot, fault->gfn, true, true,
-					  fault->write, &fault->map_writable);
+	foll |= FOLL_INTERRUPTIBLE;
+	foll &= ~FOLL_NOWAIT;
+	fault->pfn = __kvm_faultin_pfn(fault->slot, fault->gfn, foll,
+				       &fault->map_writable, &fault->refcounted_page);
+
 	return RET_PF_CONTINUE;
 }
 
diff --git a/arch/x86/kvm/mmu/mmu_internal.h b/arch/x86/kvm/mmu/mmu_internal.h
index 59e600f6ff9d..fabbea504a69 100644
--- a/arch/x86/kvm/mmu/mmu_internal.h
+++ b/arch/x86/kvm/mmu/mmu_internal.h
@@ -238,6 +238,7 @@  struct kvm_page_fault {
 	/* Outputs of kvm_mmu_faultin_pfn().  */
 	unsigned long mmu_seq;
 	kvm_pfn_t pfn;
+	struct page *refcounted_page;
 	bool map_writable;
 
 	/*