libxl: properly set default of discard_enable

Initialze discard_enable properly. This avoids a crash if a
libxl_device_disk with an uninitialized discard_enable is passed to
device_disk_add. Up to now only xl initialized discard_enable in its
config parser. External users of libxl, such as libvirt, do not need to
provide a default value.

Signed-off-by: Olaf Hering <olaf@aepfle.de>
Acked-by: Ian Campbell <ian.campbell@citrix.com>

diff --git a/tools/libxl/libxl.c b/tools/libxl/libxl.c
index 4b66afc7b2482042ad8f77c65f0b6b6b6c1e36aa..9054c3b353190b6ebc110e8a0a69a42be5666cac 100644 (file)
--- a/tools/libxl/libxl.c
+++ b/tools/libxl/libxl.c
@@ -2025,6 +2025,8 @@ int libxl__device_disk_setdefault(libxl__gc *gc, libxl_device_disk *disk)
 {
     int rc;
 
+    libxl_defbool_setdefault(&disk->discard_enable, !!disk->readwrite);
+
     rc = libxl__resolve_domid(gc, disk->backend_domname, &disk->backend_domid);
     if (rc < 0) return rc;
 

diff --git a/tools/libxl/libxlu_disk.c b/tools/libxl/libxlu_disk.c
index 752a2c7cdc08ff42849156ad0e75f31b8bcc3726..18fe386dbe2f0adff504af5863c2e30d4c09975d 100644 (file)
--- a/tools/libxl/libxlu_disk.c
+++ b/tools/libxl/libxlu_disk.c
@@ -79,7 +79,6 @@ int xlu_disk_parse(XLU_Config *cfg,
         if (!disk->pdev_path || !strcmp(disk->pdev_path, ""))
             disk->format = LIBXL_DISK_FORMAT_EMPTY;
     }
-    libxl_defbool_setdefault(&disk->discard_enable, !!disk->readwrite);
 
     if (!disk->vdev) {
         xlu__disk_err(&dpc,0, "no vdev specified");