[Xen-devel] [PATCH 2/4] x86: relax a few get_gfn() invocations

["Jan Beulich" <JBeulich@xxxxxxxx>]

In a few cases only a query is intended, i.e. without populating a
possible PoD or paged out entry, when the intention is to replace the
current entry anyway. Use get_gfn_query() there instead.

Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>

--- a/xen/arch/x86/hvm/grant_table.c
+++ b/xen/arch/x86/hvm/grant_table.c
@@ -59,7 +59,7 @@ int replace_grant_p2m_mapping(uint64_t a
     if ( new_addr != 0 || (flags & GNTMAP_contains_pte) )
         return GNTST_general_error;
 
-    old_mfn = get_gfn(d, gfn, &type);
+    old_mfn = get_gfn_query(d, gfn, &type);
     if ( !p2m_is_grant(type) || !mfn_eq(old_mfn, frame) )
     {
         put_gfn(d, gfn);
--- a/xen/arch/x86/mm.c
+++ b/xen/arch/x86/mm.c
@@ -4516,7 +4516,7 @@ int xenmem_add_to_physmap_one(
     }
 
     /* Remove previously mapped page if it was present. */
-    prev_mfn = mfn_x(get_gfn(d, gfn_x(gpfn), &p2mt));
+    prev_mfn = mfn_x(get_gfn_query(d, gfn_x(gpfn), &p2mt));
     if ( mfn_valid(_mfn(prev_mfn)) )
     {
         if ( is_xen_heap_mfn(prev_mfn) )
--- a/xen/arch/x86/mm/p2m.c
+++ b/xen/arch/x86/mm/p2m.c
@@ -2938,7 +2938,7 @@ int p2m_add_foreign(struct domain *tdom,
     mfn = page_to_mfn(page);
 
     /* Remove previously mapped page if it is present. */
-    prev_mfn = get_gfn(tdom, gpfn, &p2mt_prev);
+    prev_mfn = get_gfn_query(tdom, gpfn, &p2mt_prev);
     if ( mfn_valid(prev_mfn) )
     {
         if ( is_xen_heap_mfn(mfn_x(prev_mfn)) )





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