virfile: Introduce and use virFileGetDefaultHugepage

This helper returns the default hugetlbfs mount point from given
array of mount points.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>

src/libvirt_private.syms

@@ -1864,6 +1864,7 @@ virFileFindResourceFull;
 virFileFlock;
 virFileFreeACLs;
 virFileGetACLs;
+virFileGetDefaultHugepage;
 virFileGetHugepageSize;
 virFileGetMountReverseSubtree;
 virFileGetMountSubtree;

src/qemu/qemu_conf.c

@@ -1914,16 +1914,12 @@ qemuGetDomainDefaultHugepath(const virDomainDef *def,
                              virHugeTLBFSPtr hugetlbfs,
                              size_t nhugetlbfs)
 {
-    size_t i;
+    virHugeTLBFSPtr p;
 
-    for (i = 0; i < nhugetlbfs; i++)
-        if (hugetlbfs[i].deflt)
-            break;
+    if (!(p = virFileGetDefaultHugepage(hugetlbfs, nhugetlbfs)))
+        p = &hugetlbfs[0];
 
-    if (i == nhugetlbfs)
-        i = 0;
-
-    return qemuGetDomainHugepagePath(def, &hugetlbfs[i]);
+    return qemuGetDomainHugepagePath(def, p);
 }
 
 

src/util/virfile.c

@@ -3735,6 +3735,31 @@ virFileFindHugeTLBFS(virHugeTLBFSPtr *ret_fs ATTRIBUTE_UNUSED,
 }
 #endif /* defined __linux__ */
 
+/**
+ * virFileGetDefaultHugepage:
+ * @fs: array of hugetlbfs mount points
+ * @nfs: number of items in @fs
+ *
+ * In the passed array of hugetlbfs mount points @fs find the
+ * default one. It's the one which has no '-o pagesize'.
+ *
+ * Returns: default hugepage, or
+ *          NULL if none found
+ */
+virHugeTLBFSPtr
+virFileGetDefaultHugepage(virHugeTLBFSPtr fs,
+                          size_t nfs)
+{
+    size_t i;
+
+    for (i = 0; i < nfs; i++) {
+        if (fs[i].deflt)
+            return &fs[i];
+    }
+
+    return NULL;
+}
+
 int virFileIsSharedFS(const char *path)
 {
     return virFileIsSharedFSType(path,

src/util/virfile.h

@@ -334,6 +334,9 @@ int virFileGetHugepageSize(const char *path,
 int virFileFindHugeTLBFS(virHugeTLBFSPtr *ret_fs,
                          size_t *ret_nfs);
 
+virHugeTLBFSPtr virFileGetDefaultHugepage(virHugeTLBFSPtr fs,
+                                          size_t nfs);
+
 int virFileSetupDev(const char *path,
                     const char *mount_options);