Re: [PATCH v1] block/stream:add flush l2_table_cache,ensure data integrity

[Vladimir Sementsov-Ogievskiy]

On 24.07.23 10:30, Evanzhang wrote:

block_stream will not actively flush l2_table_cache,when qemu
process exception exit,causing disk data loss

Signed-off-by: Evanzhang <evanzh...@archeros.com>
---
  block/stream.c | 6 ++++++
  1 file changed, 6 insertions(+)

diff --git a/block/stream.c b/block/stream.c
index e522bbd..a5e08da 100644
--- a/block/stream.c
+++ b/block/stream.c
@@ -207,6 +207,12 @@ static int coroutine_fn stream_run(Job *job, Error **errp)
          }
      }

+ /*

+     * Complete stream_populate,force flush l2_table_cache,to
+     * avoid unexpected termination of process, l2_table loss
+     */
+    qcow2_cache_flush(bs, ((BDRVQcow2State *)bs->opaque)->l2_table_cache);
+
      /* Do not remove the backing file if an error was there but ignored. */
      return error;
  }

Hi!

I think, it's more correct just call bdrv_co_flush(bs), which should do all the 
job. Also, stream_run() should fail if flush fails.

Also, I remember I've done it for all (or at least several) blockjobs 
generically, so that any blockjob must succesfully flush target to report 
success.. But now I can find neither my patches nor the code :( Den, Kevin, 
Hanna, don't you remember this topic?

--
Best regards,
Vladimir