[Qemu-block] [PATCH v2 1/2] block/rbd: enable filename option and parsing

[Jeff Cody]

When enabling option parsing and blockdev-add for rbd, we removed the
'filename' option.  Unfortunately, this was a bit optimistic, as
previous versions of QEMU allowed the use of the option in backing
filenames via json.  This means that without parsing this option, we
cannot open existing images that used to work fine.

See bug: https://bugzilla.redhat.com/show_bug.cgi?id=1457088

Tested-by: Richard W.M. Jones <address@hidden>
Signed-off-by: Jeff Cody <address@hidden>
---
 block/rbd.c | 22 +++++++++++++++++++++-
 1 file changed, 21 insertions(+), 1 deletion(-)

diff --git a/block/rbd.c b/block/rbd.c
index e551639..ff44e5f 100644
--- a/block/rbd.c
+++ b/block/rbd.c
@@ -340,6 +340,10 @@ static QemuOptsList runtime_opts = {
             .type = QEMU_OPT_STRING,
             .help = "Legacy rados key/value option parameters",
         },
+        {
+            .name = "filename",
+            .type = QEMU_OPT_STRING,
+        },
         { /* end of list */ }
     },
 };
@@ -541,12 +545,27 @@ static int qemu_rbd_open(BlockDriverState *bs, QDict 
*options, int flags,
 {
     BDRVRBDState *s = bs->opaque;
     const char *pool, *snap, *conf, *user, *image_name, *keypairs;
-    const char *secretid;
+    const char *secretid, *filename;
     QemuOpts *opts;
     Error *local_err = NULL;
     char *mon_host = NULL;
     int r;
 
+    /* If we are given a filename, parse the filename, with precedence given to
+     * filename encoded options */
+    filename = qdict_get_try_str(options, "filename");
+    if (filename) {
+        error_report("Warning: 'filename' option specified. "
+                      "This is an unsupported option, and may be deprecated "
+                      "in the future");
+        qemu_rbd_parse_filename(filename, options, &local_err);
+        if (local_err) {
+            r = -EINVAL;
+            error_propagate(errp, local_err);
+            goto exit;
+        }
+    }
+
     opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
     qemu_opts_absorb_qdict(opts, options, &local_err);
     if (local_err) {
@@ -665,6 +684,7 @@ failed_shutdown:
 failed_opts:
     qemu_opts_del(opts);
     g_free(mon_host);
+exit:
     return r;
 }
 
-- 
2.9.3