memfd: fix vhost-user-test on non-memfd capable host

[mirror_qemu.git] / util / memfd.c

diff --git a/util/memfd.c b/util/memfd.c
index 07d579ea7d9853a2e7b2a987f2ff390bde42bec2..b3ecbac19e9017e0aa4868da7837e7ec305a96e3 100644 (file)
--- a/util/memfd.c
+++ b/util/memfd.c
@@ -173,7 +173,13 @@ enum {
     MEMFD_TODO
 };
 
-bool qemu_memfd_check(void)
+/**
+ * qemu_memfd_alloc_check():
+ *
+ * Check if qemu_memfd_alloc() can allocate, including using a
+ * fallback implementation when host doesn't support memfd.
+ */
+bool qemu_memfd_alloc_check(void)
 {
     static int memfd_check = MEMFD_TODO;
 
@@ -188,3 +194,29 @@ bool qemu_memfd_check(void)
 
     return memfd_check == MEMFD_OK;
 }
+
+/**
+ * qemu_memfd_check():
+ *
+ * Check if host supports memfd.
+ */
+bool qemu_memfd_check(void)
+{
+#ifdef CONFIG_LINUX
+    static int memfd_check = MEMFD_TODO;
+
+    if (memfd_check == MEMFD_TODO) {
+        int mfd = memfd_create("test", 0);
+        if (mfd >= 0) {
+            memfd_check = MEMFD_OK;
+            close(mfd);
+        } else {
+            memfd_check = MEMFD_KO;
+        }
+    }
+
+    return memfd_check == MEMFD_OK;
+#else
+    return false;
+#endif
+}