[PATCH v2 01/12] qapi/common: Clarify what IoOperationType is for

[Hanna Czenczek <hreitz@redhat.com>]

The documentation for this type is a bit sparse right now, and
specifically does not explain why it is limited to read/write only;
"I/O operation type" could well imply this should distinguish a much
broader range of operations like flushes, discards, etc., but it does
not.

Make a note why that is, which is that these types reflect the block
device on-error policy settings that we have, which are rerror for read
and werror for write.

Signed-off-by: Hanna Czenczek <hreitz@redhat.com>
---
 qapi/common.json | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/qapi/common.json b/qapi/common.json
index 1352e664b23..880eb87a9cb 100644
--- a/qapi/common.json
+++ b/qapi/common.json
@@ -9,7 +9,10 @@
 
 ##
 # @IoOperationType:
-#     An enumeration of the I/O operation types
+#     An enumeration of the I/O operation types, limited to the block
+#     device on-error policy settings we have (rerror and werror).
+#     For reference, the corresponding error policy values are set in
+#     `BlockdevOnError`.
 #
 # @read: read operation
 #
-- 
2.55.0