[PATCH 21/29] block/export: Add BLOCK_EXPORT_DELETED event

[Kevin Wolf]

Clients may want to know when an export has finally disappeard
(block-export-del returns earlier than that in the general case), so add
a QAPI event for it.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
 qapi/block-export.json     | 12 ++++++++++++
 block/export/export.c      |  2 ++
 tests/qemu-iotests/140.out |  1 +
 tests/qemu-iotests/223.out |  4 ++++
 4 files changed, 19 insertions(+)

diff --git a/qapi/block-export.json b/qapi/block-export.json
index 77a6b595e8..dac3250f08 100644
--- a/qapi/block-export.json
+++ b/qapi/block-export.json
@@ -233,3 +233,15 @@
 ##
 { 'command': 'block-export-del',
   'data': { 'id': 'str', '*mode': 'BlockExportRemoveMode' } }
+
+##
+# @BLOCK_EXPORT_DELETED:
+#
+# Emitted when a block export is removed and it's id can be reused.
+#
+# @id: Block export id.
+#
+# Since: 5.2
+##
+{ 'event': 'BLOCK_EXPORT_DELETED',
+  'data': { 'id': 'str' } }
diff --git a/block/export/export.c b/block/export/export.c
index 4af3b69186..ae7879e6a9 100644
--- a/block/export/export.c
+++ b/block/export/export.c
@@ -19,6 +19,7 @@
 #include "block/nbd.h"
 #include "qapi/error.h"
 #include "qapi/qapi-commands-block-export.h"
+#include "qapi/qapi-events-block-export.h"
 #include "qemu/id.h"
 
 static const BlockExportDriver *blk_exp_drivers[] = {
@@ -113,6 +114,7 @@ static void blk_exp_delete_bh(void *opaque)
     assert(exp->refcount == 0);
     QLIST_REMOVE(exp, next);
     exp->drv->delete(exp);
+    qapi_event_send_block_export_deleted(exp->id);
     g_free(exp->id);
     g_free(exp);
 
diff --git a/tests/qemu-iotests/140.out b/tests/qemu-iotests/140.out
index 86b985da75..f1db409b26 100644
--- a/tests/qemu-iotests/140.out
+++ b/tests/qemu-iotests/140.out
@@ -15,6 +15,7 @@ read 65536/65536 bytes at offset 0
 qemu-io: can't open device nbd+unix:///drv?socket=SOCK_DIR/nbd: Requested 
export not available
 server reported: export 'drv' not present
 { 'execute': 'quit' }
+{"timestamp": {"seconds":  TIMESTAMP, "microseconds":  TIMESTAMP}, "event": 
"BLOCK_EXPORT_DELETED", "data": {"id": "drv"}}
 {"return": {}}
 {"timestamp": {"seconds":  TIMESTAMP, "microseconds":  TIMESTAMP}, "event": 
"SHUTDOWN", "data": {"guest": false, "reason": "host-qmp-quit"}}
 *** done
diff --git a/tests/qemu-iotests/223.out b/tests/qemu-iotests/223.out
index 31ce9e6fe0..f6eac23f04 100644
--- a/tests/qemu-iotests/223.out
+++ b/tests/qemu-iotests/223.out
@@ -102,8 +102,10 @@ read 2097152/2097152 bytes at offset 2097152
 {"execute":"nbd-server-remove", "arguments":{"name":"n"}}
 {"return": {}}
 {"execute":"nbd-server-remove", "arguments":{"name":"n2"}}
+{"timestamp": {"seconds":  TIMESTAMP, "microseconds":  TIMESTAMP}, "event": 
"BLOCK_EXPORT_DELETED", "data": {"id": "n"}}
 {"return": {}}
 {"execute":"nbd-server-remove", "arguments":{"name":"n2"}}
+{"timestamp": {"seconds":  TIMESTAMP, "microseconds":  TIMESTAMP}, "event": 
"BLOCK_EXPORT_DELETED", "data": {"id": "n2"}}
 {"error": {"class": "GenericError", "desc": "Export 'n2' is not found"}}
 {"execute":"nbd-server-stop"}
 {"return": {}}
@@ -183,8 +185,10 @@ read 2097152/2097152 bytes at offset 2097152
 {"execute":"nbd-server-remove", "arguments":{"name":"n"}}
 {"return": {}}
 {"execute":"nbd-server-remove", "arguments":{"name":"n2"}}
+{"timestamp": {"seconds":  TIMESTAMP, "microseconds":  TIMESTAMP}, "event": 
"BLOCK_EXPORT_DELETED", "data": {"id": "n"}}
 {"return": {}}
 {"execute":"nbd-server-remove", "arguments":{"name":"n2"}}
+{"timestamp": {"seconds":  TIMESTAMP, "microseconds":  TIMESTAMP}, "event": 
"BLOCK_EXPORT_DELETED", "data": {"id": "n2"}}
 {"error": {"class": "GenericError", "desc": "Export 'n2' is not found"}}
 {"execute":"nbd-server-stop"}
 {"return": {}}
-- 
2.25.4