qemu: Separate out hugepages basedir making

During its initialization, the QEMU driver iterates over
hugetlbfs mount points, creating the driver specific path in each
of them ($prefix/libvirt/qemu). This path is created with very
wide mode (0777) because per-domain directories are then created
under it.

Separate this code into a function so that it can be re-used.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>

src/qemu/qemu_conf.c

@@ -1576,3 +1576,30 @@ qemuGetMemoryBackingPath(virQEMUDriver *driver,
     *memPath = g_strdup_printf("%s/%s", domainPath, alias);
     return 0;
 }
+
+
+int
+qemuHugepageMakeBasedir(virQEMUDriver *driver,
+                        virHugeTLBFS *hugepage)
+{
+
+    g_autofree char *hugepagePath = NULL;
+
+    hugepagePath = qemuGetBaseHugepagePath(driver, hugepage);
+
+    if (!hugepagePath)
+        return -1;
+
+    if (g_mkdir_with_parents(hugepagePath, 0777) < 0) {
+        virReportSystemError(errno,
+                             _("unable to create hugepage path %s"),
+                             hugepagePath);
+        return -1;
+    }
+
+    if (driver->privileged &&
+        virFileUpdatePerm(hugepage->mnt_dir, 0, S_IXGRP | S_IXOTH) < 0)
+        return -1;
+
+    return 0;
+}

src/qemu/qemu_conf.h

@@ -359,3 +359,6 @@ int qemuGetMemoryBackingPath(virQEMUDriver *driver,
                              const virDomainDef *def,
                              const char *alias,
                              char **memPath);
+
+int qemuHugepageMakeBasedir(virQEMUDriver *driver,
+                            virHugeTLBFS *hugepage);

src/qemu/qemu_driver.c

@@ -837,22 +837,7 @@ qemuStateInitialize(bool privileged,
      * it, since we can't assume the root mount point has permissions that
      * will let our spawned QEMU instances use it. */
     for (i = 0; i < cfg->nhugetlbfs; i++) {
-        g_autofree char *hugepagePath = NULL;
+        if (qemuHugepageMakeBasedir(qemu_driver, &cfg->hugetlbfs[i]) < 0)
-
-        hugepagePath = qemuGetBaseHugepagePath(qemu_driver, &cfg->hugetlbfs[i]);
-
-        if (!hugepagePath)
-            goto error;
-
-        if (g_mkdir_with_parents(hugepagePath, 0777) < 0) {
-            virReportSystemError(errno,
-                                 _("unable to create hugepage path %s"),
-                                 hugepagePath);
-            goto error;
-        }
-        if (privileged &&
-            virFileUpdatePerm(cfg->hugetlbfs[i].mnt_dir,
-                              0, S_IXGRP | S_IXOTH) < 0)
             goto error;
     }