uuid: Make qemu_uuid_bswap() take and return a QemuUUID

Currently qemu_uuid_bswap() takes a pointer to the QemuUUID to
be byte-swapped. This means it can't be used when the UUID
to be swapped is in a packed member of a struct. It's also
out of line with the general bswap*() functions we provide
in bswap.h, which take the value to be swapped and return it.

Make qemu_uuid_bswap() take a QemuUUID and return the swapped version.

This fixes some clang warnings about taking the address of
a packed struct member in block/vdi.c.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

1 files changed, 2 insertions, 4 deletions

diff --git a/hw/acpi/vmgenid.c b/hw/acpi/vmgenid.c
index d78b579..02717a8 100644
--- a/hw/acpi/vmgenid.c
+++ b/hw/acpi/vmgenid.c
@@ -30,8 +30,7 @@ void vmgenid_build_acpi(VmGenIdState *vms, GArray *table_data, GArray *guid,
      * first, since that's what the guest expects
      */
     g_array_set_size(guid, VMGENID_FW_CFG_SIZE - ARRAY_SIZE(guid_le.data));
-    guid_le = vms->guid;
-    qemu_uuid_bswap(&guid_le);
+    guid_le = qemu_uuid_bswap(vms->guid);
     /* The GUID is written at a fixed offset into the fw_cfg file
      * in order to implement the "OVMF SDT Header probe suppressor"
      * see docs/specs/vmgenid.txt for more details
@@ -149,8 +148,7 @@ static void vmgenid_update_guest(VmGenIdState *vms)
              * however, will expect the fields to be little-endian.
              * Perform a byte swap immediately before writing.
              */
-            guid_le = vms->guid;
-            qemu_uuid_bswap(&guid_le);
+            guid_le = qemu_uuid_bswap(vms->guid);
             /* The GUID is written at a fixed offset into the fw_cfg file
              * in order to implement the "OVMF SDT Header probe suppressor"
              * see docs/specs/vmgenid.txt for more details.