Revert "add_drive_ro adds readonly=on option if available." (RHBZ#617200).

[libguestfs.git] / src / guestfs.c

diff --git a/src/guestfs.c b/src/guestfs.c
index 28f269a..e55b9ba 100644 (file)
--- a/src/guestfs.c
+++ b/src/guestfs.c
@@ -830,6 +830,9 @@ int
 guestfs__add_drive_ro_with_if (guestfs_h *g, const char *filename,
                                const char *drive_if)
 {
+  size_t len = strlen (filename) + 64;
+  char buf[len];
+
   if (strchr (filename, ',') != NULL) {
     error (g, _("filename cannot contain ',' (comma) character"));
     return -1;
@@ -840,24 +843,7 @@ guestfs__add_drive_ro_with_if (guestfs_h *g, const char *filename,
     return -1;
   }
 
-  if (qemu_supports (g, NULL) == -1)
-    return -1;
-
-  /* Only SCSI and virtio drivers support readonly mode.
-   * This is only supported as a QEMU feature since 2010/01.
-   */
-  int supports_ro = 0;
-  if ((STREQ (drive_if, "scsi") || STREQ (drive_if, "virtio")) &&
-      qemu_supports (g, "readonly=on"))
-    supports_ro = 1;
-
-  size_t len = strlen (filename) + 100;
-  char buf[len];
-
-  snprintf (buf, len, "file=%s,snapshot=on,%sif=%s",
-            filename,
-            supports_ro ? "readonly=on," : "",
-            drive_if);
+  snprintf (buf, len, "file=%s,snapshot=on,if=%s", filename, drive_if);
 
   return guestfs__config (g, "-drive", buf);
 }
@@ -948,9 +934,21 @@ guestfs__launch (guestfs_h *g)
   char unixsock[256];
   struct sockaddr_un addr;
 
+  /* Configured? */
+  if (!g->cmdline) {
+    error (g, _("you must call guestfs_add_drive before guestfs_launch"));
+    return -1;
+  }
+
+  if (g->state != CONFIG) {
+    error (g, _("the libguestfs handle has already been launched"));
+    return -1;
+  }
+
   /* Start the clock ... */
   gettimeofday (&g->launch_t, NULL);
 
+  /* Make the temporary directory. */
 #ifdef P_tmpdir
   tmpdir = P_tmpdir;
 #else
@@ -960,18 +958,6 @@ guestfs__launch (guestfs_h *g)
   tmpdir = getenv ("TMPDIR") ? : tmpdir;
   snprintf (dir_template, sizeof dir_template, "%s/libguestfsXXXXXX", tmpdir);
 
-  /* Configured? */
-  if (!g->cmdline) {
-    error (g, _("you must call guestfs_add_drive before guestfs_launch"));
-    return -1;
-  }
-
-  if (g->state != CONFIG) {
-    error (g, _("qemu has already been launched"));
-    return -1;
-  }
-
-  /* Make the temporary directory. */
   if (!g->tmpdir) {
     g->tmpdir = safe_strdup (g, dir_template);
     if (mkdtemp (g->tmpdir) == NULL) {