[Qemu-devel] [PATCH 3/6] block: Advertise BDRV_REQ_NO_FALLBACK in filter drivers

[Kevin Wolf]

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 <kw...@redhat.com>
---
 block/blkdebug.c     | 2 +-
 block/copy-on-read.c | 7 +++----
 block/mirror.c       | 3 ++-
 block/raw-format.c   | 2 +-
 4 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/block/blkdebug.c b/block/blkdebug.c
index 1ea835c2b9..efd9441625 100644
--- a/block/blkdebug.c
+++ b/block/blkdebug.c
@@ -401,7 +401,7 @@ static int blkdebug_open(BlockDriverState *bs, QDict 
*options, int flags,
     bs->supported_write_flags = BDRV_REQ_WRITE_UNCHANGED |
         (BDRV_REQ_FUA & bs->file->bs->supported_write_flags);
     bs->supported_zero_flags = BDRV_REQ_WRITE_UNCHANGED |
-        ((BDRV_REQ_FUA | BDRV_REQ_MAY_UNMAP) &
+        ((BDRV_REQ_FUA | BDRV_REQ_MAY_UNMAP | BDRV_REQ_NO_FALLBACK) &
             bs->file->bs->supported_zero_flags);
     ret = -EINVAL;
 
diff --git a/block/copy-on-read.c b/block/copy-on-read.c
index d670fec42b..53972b1da3 100644
--- a/block/copy-on-read.c
+++ b/block/copy-on-read.c
@@ -34,12 +34,11 @@ static int cor_open(BlockDriverState *bs, QDict *options, 
int flags,
     }
 
     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;
 }
diff --git a/block/mirror.c b/block/mirror.c
index eb9a4cdf56..ff15cfb197 100644
--- a/block/mirror.c
+++ b/block/mirror.c
@@ -1548,7 +1548,8 @@ static void mirror_start_job(const char *job_id, 
BlockDriverState *bs,
     }
     mirror_top_bs->total_sectors = bs->total_sectors;
     mirror_top_bs->supported_write_flags = BDRV_REQ_WRITE_UNCHANGED;
-    mirror_top_bs->supported_zero_flags = BDRV_REQ_WRITE_UNCHANGED;
+    mirror_top_bs->supported_zero_flags = BDRV_REQ_WRITE_UNCHANGED |
+                                          BDRV_REQ_NO_FALLBACK;
     bs_opaque = g_new0(MirrorBDSOpaque, 1);
     mirror_top_bs->opaque = bs_opaque;
     bdrv_set_aio_context(mirror_top_bs, bdrv_get_aio_context(bs));
diff --git a/block/raw-format.c b/block/raw-format.c
index cec29986cc..385cdc2490 100644
--- a/block/raw-format.c
+++ b/block/raw-format.c
@@ -434,7 +434,7 @@ static int raw_open(BlockDriverState *bs, QDict *options, 
int flags,
     bs->supported_write_flags = BDRV_REQ_WRITE_UNCHANGED |
         (BDRV_REQ_FUA & bs->file->bs->supported_write_flags);
     bs->supported_zero_flags = BDRV_REQ_WRITE_UNCHANGED |
-        ((BDRV_REQ_FUA | BDRV_REQ_MAY_UNMAP) &
+        ((BDRV_REQ_FUA | BDRV_REQ_MAY_UNMAP | BDRV_REQ_NO_FALLBACK) &
             bs->file->bs->supported_zero_flags);
 
     if (bs->probed && !bdrv_is_read_only(bs)) {
-- 
2.20.1