blockdev: Clean up how readonly persists across virtual media change

Since commit cb4e5f8e, monitor command change makes the new media
readonly iff the type hint is BDRV_TYPE_CDROM, i.e. the drive was
created with media=cdrom.  The intention is to avoid changing a block
device's read-only-ness.  However, BDRV_TYPE_CDROM is only a hint.  It
is currently sufficent for read-only.  But it's not necessary, and it
may not remain sufficient.

Use bdrv_is_read_only() instead.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

diff --git a/blockdev.c b/blockdev.c
index be88098d53e7e4ab66cd74f12701bfdad5e27ffd..0a9dec364e40eef673e1f87b0e5ee2c2b5a1194a 100644 (file)
--- a/blockdev.c
+++ b/blockdev.c
@@ -589,7 +589,7 @@ int do_change_block(Monitor *mon, const char *device,
     if (eject_device(mon, bs, 0) < 0) {
         return -1;
     }
-    bdrv_flags = bdrv_get_type_hint(bs) == BDRV_TYPE_CDROM ? 0 : BDRV_O_RDWR;
+    bdrv_flags = bdrv_is_read_only(bs) ? 0 : BDRV_O_RDWR;
     if (bdrv_open(bs, filename, bdrv_flags, drv) < 0) {
         qerror_report(QERR_OPEN_FILE_FAILED, filename);
         return -1;