commit 80f5c33ff31eb9333f5036ee278fb1483fb4ff41
author Kevin Wolf <kwolf@redhat.com> Fri Mar 22 13:42:39 2019 +0100
committer Kevin Wolf <kwolf@redhat.com> Tue Mar 26 11:37:51 2019 +0100
tree b6c7859b0df98a34a54e1f3a10d742f74eb2f614
parent fe0480d6294270ff0d6fb60e66bb725a6aad2043

block: Advertise BDRV_REQ_NO_FALLBACK in filter drivers

Filter drivers that support .bdrv_co_pwrite_zeroes can safely advertise
BDRV_REQ_NO_FALLBACK because they just forward the request flags to
their child node.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Eric Blake <eblake@redhat.com>

block/copy-on-read.c

diff --git a/block/copy-on-read.c b/block/copy-on-read.c
index d670fec..53972b1 100644
--- a/block/copy-on-read.c
+++ b/block/copy-on-read.c
@@ -34,12 +34,11 @@
     }
 
     bs->supported_write_flags = BDRV_REQ_WRITE_UNCHANGED |
-                                (BDRV_REQ_FUA &
-                                    bs->file->bs->supported_write_flags);
+        (BDRV_REQ_FUA & bs->file->bs->supported_write_flags);
 
     bs->supported_zero_flags = BDRV_REQ_WRITE_UNCHANGED |
-                               ((BDRV_REQ_FUA | BDRV_REQ_MAY_UNMAP) &
-                                    bs->file->bs->supported_zero_flags);
+        ((BDRV_REQ_FUA | BDRV_REQ_MAY_UNMAP | BDRV_REQ_NO_FALLBACK) &
+            bs->file->bs->supported_zero_flags);
 
     return 0;
 }