[PATCH 10/16] KVM: Use gfn_to_pfn_cache's immutable "kvm" in kvm_gpc_refresh()

From: Paolo Bonzini
Date: Thu Oct 27 2022 - 12:19:34 EST


From: Michal Luczaj <mhal@xxxxxxx>

Make kvm_gpc_refresh() use kvm instance cached in gfn_to_pfn_cache.

No functional change intended.

Suggested-by: Sean Christopherson <seanjc@xxxxxxxxxx>
Signed-off-by: Michal Luczaj <mhal@xxxxxxx>
[sean: leave kvm_gpc_unmap() as-is]
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
Message-Id: <20221013211234.1318131-11-seanjc@xxxxxxxxxx>
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
---
arch/x86/kvm/x86.c | 2 +-
arch/x86/kvm/xen.c | 8 ++++----
include/linux/kvm_host.h | 8 +++-----
virt/kvm/pfncache.c | 11 +++++------
4 files changed, 13 insertions(+), 16 deletions(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 0e3546aa34dd..bdc3110650d3 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3037,7 +3037,7 @@ 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 d3cb28388e3c..545ecbd0ca36 100644
--- a/arch/x86/kvm/xen.c
+++ b/arch/x86/kvm/xen.c
@@ -248,7 +248,7 @@ 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);
@@ -377,7 +377,7 @@ 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);
@@ -451,7 +451,7 @@ 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.
@@ -1504,7 +1504,7 @@ 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 466988b8b5f6..d4a49c89bc08 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -1299,22 +1299,20 @@ 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 48f400819d1e..e4ebea75dca9 100644
--- a/virt/kvm/pfncache.c
+++ b/virt/kvm/pfncache.c
@@ -237,10 +237,9 @@ static kvm_pfn_t hva_to_pfn_retry(struct gfn_to_pfn_cache *gpc)
return -EFAULT;
}

-static int __kvm_gpc_refresh(struct kvm *kvm, struct gfn_to_pfn_cache *gpc, gpa_t gpa,
- unsigned long len)
+static int __kvm_gpc_refresh(struct gfn_to_pfn_cache *gpc, gpa_t gpa, unsigned long len)
{
- 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;
@@ -330,9 +329,9 @@ static int __kvm_gpc_refresh(struct kvm *kvm, struct gfn_to_pfn_cache *gpc, gpa_
return ret;
}

-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)
{
- return __kvm_gpc_refresh(kvm, gpc, gpa, gpc->len);
+ return __kvm_gpc_refresh(gpc, gpa, gpc->len);
}
EXPORT_SYMBOL_GPL(kvm_gpc_refresh);

@@ -401,7 +400,7 @@ int kvm_gpc_activate(struct gfn_to_pfn_cache *gpc, gpa_t gpa, unsigned long len)
gpc->active = true;
write_unlock_irq(&gpc->lock);
}
- return __kvm_gpc_refresh(kvm, gpc, gpa, len);
+ return __kvm_gpc_refresh(gpc, gpa, len);
}
EXPORT_SYMBOL_GPL(kvm_gpc_activate);

--
2.31.1