'discard' is one of the basic BlockdevOptions available for all
drivers, but it's not handled by bdrv_reopen_prepare() so any attempt
to change it results in an error:
(qemu) qemu-io virtio0 "reopen -o discard=on"
Cannot change the option 'discard'
Since there's no reason why we shouldn't allow changing it and the
implementation is simple let's just do it.
Signed-off-by: Alberto Garcia <be...@igalia.com>
Cc: Max Reitz <mre...@redhat.com>
---
block.c | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/block.c b/block.c
index 1c0f72454a..3f4b7640fa 100644
--- a/block.c
+++ b/block.c
@@ -3155,6 +3155,7 @@ int bdrv_reopen_prepare(BDRVReopenState *reopen_state,
BlockReopenQueue *queue,
BlockDriver *drv;
QemuOpts *opts;
QDict *orig_reopen_opts;
+ const char *value;
bool read_only;
assert(reopen_state != NULL);
@@ -3177,6 +3178,15 @@ int bdrv_reopen_prepare(BDRVReopenState *reopen_state,
BlockReopenQueue *queue,
update_flags_from_options(&reopen_state->flags, opts);
+ value = qemu_opt_get_del(opts, "discard");
+ if (value != NULL) {
+ if (bdrv_parse_discard_flags(value, &reopen_state->flags) != 0) {
+ error_setg(errp, "Invalid discard option");
+ ret = -EINVAL;
+ goto error;
+ }
+ }
+
/* All other options (including node-name and driver) must be unchanged.
* Put them back into the QDict, so that they are checked at the end
* of this function. */
--
2.11.0
