qapi: Document meaning of 'ignore' BlockdevOnError for jobs

It is not obvious what 'ignore' actually means for block jobs: It could
be continuing the job and returning success in the end despite the error
(no block job does this). It could also mean continuing and returning
failure in the end (this is what stream does). And it can mean retrying
the failed request later (this is what backup, commit and mirror do).

This (somewhat inconsistent) behaviour was introduced and described for
stream and mirror in commit 32c81a4a6ec. backup and commit were
introduced later and use the same model as mirror.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20200214200812.28180-2-kwolf@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

diff --git a/qapi/block-core.json b/qapi/block-core.json
index 13dad62f4418d6f55a084be11dc5d19ccf5654bf..1c32158d11569698b142cff53b28f6e157a11900 100644 (file)
--- a/qapi/block-core.json
+++ b/qapi/block-core.json
@@ -1164,7 +1164,10 @@
 #          for jobs, cancel the job
 #
 # @ignore: ignore the error, only report a QMP event (BLOCK_IO_ERROR
-#          or BLOCK_JOB_ERROR)
+#          or BLOCK_JOB_ERROR). The backup, mirror and commit block jobs retry
+#          the failing request later and may still complete successfully. The
+#          stream block job continues to stream and will complete with an
+#          error.
 #
 # @enospc: same as @stop on ENOSPC, same as @report otherwise.
 #