qemu-img: block: dont blk_make_zero if discard_zeroes false

Signed-off-by: Jinhua Cao <caojinhua1@huawei.com>

qemu-img-block-dont-blk_make_zero-if-discard_zeroes-.patch

@@ -0,0 +1,26 @@
+From 724134432ef21f1fb2b18bbe55b891d31181ccca Mon Sep 17 00:00:00 2001
+From: Jinhua Cao <caojinhua1@huawei.com>
+Date: Fri, 11 Feb 2022 14:25:39 +0800
+Subject: [PATCH] qemu-img: block: dont blk_make_zero if discard_zeroes false
+
+Signed-off-by: Jinhua Cao <caojinhua1@huawei.com>
+---
+ block/file-posix.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/block/file-posix.c b/block/file-posix.c
+index b283093e5b..aed7529f44 100644
+--- a/block/file-posix.c
++++ b/block/file-posix.c
+@@ -804,7 +804,7 @@ static int raw_open_common(BlockDriverState *bs, QDict *options,
+     }
+ #endif
+ 
+-    bs->supported_zero_flags = BDRV_REQ_MAY_UNMAP | BDRV_REQ_NO_FALLBACK;
++    bs->supported_zero_flags = s->discard_zeroes ? (BDRV_REQ_MAY_UNMAP | BDRV_REQ_NO_FALLBACK) : 0;
+     if (S_ISREG(st.st_mode)) {
+         /* When extending regular files, we get zeros from the OS */
+         bs->supported_truncate_flags = BDRV_REQ_ZERO_WRITE;
+-- 
+2.27.0
+