qemu-nbd allows use of writethrough cache modes, which mean that write
requests made through NBD will cause a flush before they complete.
Expose the same functionality in block-export-add.
Signed-off-by: Kevin Wolf <kw...@redhat.com>
Reviewed-by: Max Reitz <mre...@redhat.com>
---
qapi/block-export.json | 7 ++++++-
blockdev-nbd.c | 6 +++++-
2 files changed, 11 insertions(+), 2 deletions(-)
diff --git a/qapi/block-export.json b/qapi/block-export.json
index 60474bfacd..319a38be88 100644
--- a/qapi/block-export.json
+++ b/qapi/block-export.json
@@ -170,10 +170,15 @@
# Describes a block export, i.e. how single node should be exported on an
# external interface.
#
+# @writethrough: If true, caches are flushed after every write request to the
+# export before completion is signalled. (since: 5.2;
+# default: false)
+#
# Since: 4.2
##
{ 'union': 'BlockExportOptions',
- 'base': { 'type': 'BlockExportType' },
+ 'base': { 'type': 'BlockExportType',
+ '*writethrough': 'bool' },
'discriminator': 'type',
'data': {
'nbd': 'BlockExportOptionsNbd'
diff --git a/blockdev-nbd.c b/blockdev-nbd.c
index 41d5542987..09247a8ded 100644
--- a/blockdev-nbd.c
+++ b/blockdev-nbd.c
@@ -216,9 +216,13 @@ BlockExport *nbd_export_create(BlockExportOptions
*exp_args, Error **errp)
goto out;
}
+ if (!exp_args->has_writethrough) {
+ exp_args->writethrough = false;
+ }
+
exp = nbd_export_new(bs, arg->name, arg->description, arg->bitmap,
!arg->writable, !arg->writable,
- NULL, false, errp);
+ NULL, exp_args->writethrough, errp);
if (!exp) {
goto out;
}
--
2.25.4
