linux-kernel - [PATCH v2 10/16] KVM: Use gfn_to_pfn_cache's immutable "kvm" in kvm_gpc

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Date:   Thu, 13 Oct 2022 21:12:28 +0000
From:   Sean Christopherson <seanjc@...gle.com>
To:     Sean Christopherson <seanjc@...gle.com>,
        Paolo Bonzini <pbonzini@...hat.com>
Cc:     kvm@...r.kernel.org, linux-kernel@...r.kernel.org,
        Michal Luczaj <mhal@...x.co>,
        David Woodhouse <dwmw2@...radead.org>
Subject: [PATCH v2 10/16] KVM: Use gfn_to_pfn_cache's immutable "kvm" in kvm_gpc_refresh()

From: Michal Luczaj <mhal@...x.co>

Make kvm_gpc_refresh() use kvm instance cached in gfn_to_pfn_cache.

No functional change intended.

Suggested-by: Sean Christopherson <seanjc@...gle.com>
Signed-off-by: Michal Luczaj <mhal@...x.co>
[sean: leave kvm_gpc_unmap() as-is]
Signed-off-by: Sean Christopherson <seanjc@...gle.com>
---
 arch/x86/kvm/x86.c       | 2 +-
 arch/x86/kvm/xen.c       | 8 ++++----
 include/linux/kvm_host.h | 8 +++-----
 virt/kvm/pfncache.c      | 6 +++---
 4 files changed, 11 insertions(+), 13 deletions(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index b357a84f8c49..d370d06bb07a 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3036,7 +3036,7 @@ static void kvm_setup_guest_pvclock(struct kvm_vcpu *v,
 	while (!kvm_gpc_check(gpc, gpc->gpa)) {
 		read_unlock_irqrestore(&gpc->lock, flags);
 
-		if (kvm_gpc_refresh(v->kvm, gpc, gpc->gpa))
+		if (kvm_gpc_refresh(gpc, gpc->gpa))
 			return;
 
 		read_lock_irqsave(&gpc->lock, flags);
diff --git a/arch/x86/kvm/xen.c b/arch/x86/kvm/xen.c
index c7304f37c438..920ba5ca3016 100644
--- a/arch/x86/kvm/xen.c
+++ b/arch/x86/kvm/xen.c
@@ -218,7 +218,7 @@ void kvm_xen_update_runstate_guest(struct kvm_vcpu *v, int state)
 		if (state == RUNSTATE_runnable)
 			return;
 
-		if (kvm_gpc_refresh(v->kvm, gpc, gpc->gpa))
+		if (kvm_gpc_refresh(gpc, gpc->gpa))
 			return;
 
 		read_lock_irqsave(&gpc->lock, flags);
@@ -347,7 +347,7 @@ void kvm_xen_inject_pending_events(struct kvm_vcpu *v)
 	while (!kvm_gpc_check(gpc, gpc->gpa)) {
 		read_unlock_irqrestore(&gpc->lock, flags);
 
-		if (kvm_gpc_refresh(v->kvm, gpc, gpc->gpa))
+		if (kvm_gpc_refresh(gpc, gpc->gpa))
 			return;
 
 		read_lock_irqsave(&gpc->lock, flags);
@@ -421,7 +421,7 @@ int __kvm_xen_has_interrupt(struct kvm_vcpu *v)
 		if (in_atomic() || !task_is_running(current))
 			return 1;
 
-		if (kvm_gpc_refresh(v->kvm, gpc, gpc->gpa)) {
+		if (kvm_gpc_refresh(gpc, gpc->gpa)) {
 			/*
 			 * If this failed, userspace has screwed up the
 			 * vcpu_info mapping. No interrupts for you.
@@ -1470,7 +1470,7 @@ static int kvm_xen_set_evtchn(struct kvm_xen_evtchn *xe, struct kvm *kvm)
 			break;
 
 		idx = srcu_read_lock(&kvm->srcu);
-		rc = kvm_gpc_refresh(kvm, gpc, gpc->gpa);
+		rc = kvm_gpc_refresh(gpc, gpc->gpa);
 		srcu_read_unlock(&kvm->srcu, idx);
 	} while(!rc);
 
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index ad8ef7f2d705..b63d2abbef56 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -1300,22 +1300,20 @@ bool kvm_gpc_check(struct gfn_to_pfn_cache *gpc, gpa_t gpa);
 /**
  * kvm_gpc_refresh - update a previously initialized cache.
  *
- * @kvm:	   pointer to kvm instance.
  * @gpc:	   struct gfn_to_pfn_cache object.
  * @gpa:	   updated guest physical address to map.
- * @len:	   sanity check; the range being access must fit a single page.
  *
  * @return:	   0 for success.
  *		   -EINVAL for a mapping which would cross a page boundary.
- *                 -EFAULT for an untranslatable guest physical address.
+ *		   -EFAULT for an untranslatable guest physical address.
  *
  * This will attempt to refresh a gfn_to_pfn_cache. Note that a successful
- * returm from this function does not mean the page can be immediately
+ * return from this function does not mean the page can be immediately
  * accessed because it may have raced with an invalidation. Callers must
  * still lock and check the cache status, as this function does not return
  * with the lock still held to permit access.
  */
-int kvm_gpc_refresh(struct kvm *kvm, struct gfn_to_pfn_cache *gpc, gpa_t gpa);
+int kvm_gpc_refresh(struct gfn_to_pfn_cache *gpc, gpa_t gpa);
 
 /**
  * kvm_gpc_unmap - temporarily unmap a gfn_to_pfn_cache.
diff --git a/virt/kvm/pfncache.c b/virt/kvm/pfncache.c
index ef7ac1666847..432b150bd9f1 100644
--- a/virt/kvm/pfncache.c
+++ b/virt/kvm/pfncache.c
@@ -237,9 +237,9 @@ static kvm_pfn_t hva_to_pfn_retry(struct gfn_to_pfn_cache *gpc)
 	return -EFAULT;
 }
 
-int kvm_gpc_refresh(struct kvm *kvm, struct gfn_to_pfn_cache *gpc, gpa_t gpa)
+int kvm_gpc_refresh(struct gfn_to_pfn_cache *gpc, gpa_t gpa)
 {
-	struct kvm_memslots *slots = kvm_memslots(kvm);
+	struct kvm_memslots *slots = kvm_memslots(gpc->kvm);
 	unsigned long page_offset = gpa & ~PAGE_MASK;
 	bool unmap_old = false;
 	unsigned long old_uhva;
@@ -395,7 +395,7 @@ int kvm_gpc_activate(struct gfn_to_pfn_cache *gpc, gpa_t gpa)
 		gpc->active = true;
 		write_unlock_irq(&gpc->lock);
 	}
-	return kvm_gpc_refresh(kvm, gpc, gpa);
+	return kvm_gpc_refresh(gpc, gpa);
 }
 EXPORT_SYMBOL_GPL(kvm_gpc_activate);
 
-- 
2.38.0.413.g74048e4d9e-goog