KVM: Drop FOLL_GET in GUP when doing async page fault

Page pinning is not mandatory in kvm async page fault processing since
after async page fault event is delivered to a guest it accesses page once
again and does its own GUP.  Drop the FOLL_GET flag in GUP in async_pf
code, and do some simplifying in check/clear processing.

Suggested-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Gu zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: chai wen <chaiw.fnst@cn.fujitsu.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>

2 files changed, 5 insertions, 7 deletions

diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index f6dccde755f6..c9d4236ab442 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -189,7 +189,7 @@ struct kvm_async_pf {
         gva_t gva;
         unsigned long addr;
         struct kvm_arch_async_pf arch;
-        struct page *page;
+        bool   wakeup_all;
 };
 
 void kvm_clear_async_pf_completion_queue(struct kvm_vcpu *vcpu);
diff --git a/include/trace/events/kvm.h b/include/trace/events/kvm.h
index 7005d1109ec9..131a0bda7aec 100644
--- a/include/trace/events/kvm.h
+++ b/include/trace/events/kvm.h
@@ -296,23 +296,21 @@ DEFINE_EVENT(kvm_async_pf_nopresent_ready, kvm_async_pf_ready,
 
 TRACE_EVENT(
         kvm_async_pf_completed,
-        TP_PROTO(unsigned long address, struct page *page, u64 gva),
-        TP_ARGS(address, page, gva),
+        TP_PROTO(unsigned long address, u64 gva),
+        TP_ARGS(address, gva),
 
         TP_STRUCT__entry(
                 __field(unsigned long, address)
-                __field(pfn_t, pfn)
                 __field(u64, gva)
                 ),
 
         TP_fast_assign(
                 __entry->address = address;
-                __entry->pfn = page ? page_to_pfn(page) : 0;
                 __entry->gva = gva;
                 ),
 
-        TP_printk("gva %#llx address %#lx pfn %#llx",  __entry->gva,
-                  __entry->address, __entry->pfn)
+        TP_printk("gva %#llx address %#lx",  __entry->gva,
+                  __entry->address)
 );
 
 #endif