File xsa299-5.patch of Package xen.25143

From 13660d718ec3a119ff0ab1f1197d0796ca79c668 Mon Sep 17 00:00:00 2001
From: George Dunlap <george.dunlap@citrix.com>
Date: Thu, 10 Oct 2019 17:57:49 +0100
Subject: [PATCH 05/12] x86/mm: Use flags for _put_page_type rather than a
 boolean

This is in mainly in preparation for _put_page_type taking the
partial_flags value in the future.  It also makes it easier to read in
the caller (since you see a flag name rather than `true` or `false`).

No functional change intended.

This is part of XSA-299.

Reported-by: George Dunlap <george.dunlap@citrix.com>
Signed-off-by: George Dunlap <george.dunlap@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
---
 xen/arch/x86/mm.c | 25 +++++++++++++------------
 1 file changed, 13 insertions(+), 12 deletions(-)

--- a/xen/arch/x86/mm.c
+++ b/xen/arch/x86/mm.c
@@ -1391,7 +1391,7 @@ get_page_from_l4e(
             l3e_remove_flags((pl3e), _PAGE_USER|_PAGE_RW|_PAGE_ACCESSED);   \
     } while ( 0 )
 
-static int _put_page_type(struct page_info *page, bool_t preemptible,
+static int _put_page_type(struct page_info *page, unsigned int flags,
                           struct page_info *ptpg);
 
 void put_page_from_l1e(l1_pgentry_t l1e, struct domain *l1e_owner)
@@ -1474,7 +1474,7 @@ static int put_page_from_l2e(l2_pgentry_
               PTF_partial_set )
         {
             ASSERT(!(flags & PTF_defer));
-            rc = _put_page_type(pg, 1, ptpg);
+            rc = _put_page_type(pg, PTF_preemptible, ptpg);
         }
         else if ( flags & PTF_defer )
         {
@@ -1483,7 +1483,7 @@ static int put_page_from_l2e(l2_pgentry_
         }
         else
         {
-            rc = _put_page_type(pg, 1, ptpg);
+            rc = _put_page_type(pg, PTF_preemptible, ptpg);
             if ( likely(!rc) )
                 put_page(pg);
         }
@@ -1520,7 +1520,7 @@ static int put_page_from_l3e(l3_pgentry_
          PTF_partial_set )
     {
         ASSERT(!(flags & PTF_defer));
-        return _put_page_type(pg, 1, mfn_to_page(pfn));
+        return _put_page_type(pg, PTF_preemptible, mfn_to_page(pfn));
     }
 
     if ( flags & PTF_defer )
@@ -1530,7 +1530,7 @@ static int put_page_from_l3e(l3_pgentry_
         return 0;
     }
 
-    rc = _put_page_type(pg, 1, mfn_to_page(pfn));
+    rc = _put_page_type(pg, PTF_preemptible, mfn_to_page(pfn));
     if ( likely(!rc) )
         put_page(pg);
 
@@ -1551,7 +1551,7 @@ static int put_page_from_l4e(l4_pgentry_
               PTF_partial_set )
         {
             ASSERT(!(flags & PTF_defer));
-            return _put_page_type(pg, 1, mfn_to_page(pfn));
+            return _put_page_type(pg, PTF_preemptible, mfn_to_page(pfn));
         }
 
         if ( flags & PTF_defer )
@@ -1561,7 +1561,7 @@ static int put_page_from_l4e(l4_pgentry_
             return 0;
         }
 
-        rc = _put_page_type(pg, 1, mfn_to_page(pfn));
+        rc = _put_page_type(pg, PTF_preemptible, mfn_to_page(pfn));
         if ( likely(!rc) )
             put_page(pg);
     }
@@ -2826,11 +2826,12 @@ static int _put_final_page_type(struct p
 }
 
 
-static int _put_page_type(struct page_info *page, bool_t preemptible,
+static int _put_page_type(struct page_info *page, unsigned int flags,
                           struct page_info *ptpg)
 {
     unsigned long nx, x, y = page->u.inuse.type_info;
     int rc = 0;
+    bool_t preemptible = !!(flags & PTF_preemptible);
 
     for ( ; ; )
     {
@@ -3060,7 +3061,7 @@ int get_page_type(struct page_info *page
 
 int put_page_type_preemptible(struct page_info *page)
 {
-    return _put_page_type(page, 1, NULL);
+    return _put_page_type(page, PTF_preemptible, NULL);
 }
 
 int get_page_type_preemptible(struct page_info *page, unsigned long type)
@@ -3266,7 +3267,7 @@ int put_old_guest_table(struct vcpu *v)
     if ( !v->arch.old_guest_table )
         return 0;
 
-    switch ( rc = _put_page_type(v->arch.old_guest_table, 1,
+    switch ( rc = _put_page_type(v->arch.old_guest_table, PTF_preemptible,
                                  v->arch.old_guest_ptpg) )
     {
     case -EINTR: