[Qemu-devel] [PATCH] block/quorum: make quorum_getlength error message user friendly

[Liu Yuan <namei.unix@gmail.com>]

When start quorum driver with 2 different sized images, we get:

qemu-system-x86_64: -drive if=virtio,driver=quorum...: Could not refresh total \
sector count: Input/output error

EIO would confuse users. With this patch, the error message goes like

Children images are not in the same size
qemu-system-x86_64: -drive if=virtio,driver=quorum...: Could not refresh total \
sector count: Invalid argument

Cc: Benoit Canet <benoit@irqsave.net>
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Liu Yuan <namei.unix@gmail.com>
---
 block/quorum.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/block/quorum.c b/block/quorum.c
index 2f18755..51437ad 100644
--- a/block/quorum.c
+++ b/block/quorum.c
@@ -736,7 +736,8 @@ static int64_t quorum_getlength(BlockDriverState *bs)
             return value;
         }
         if (value != result) {
-            return -EIO;
+            error_printf("Children images are not in the same size\n");
+            return -EINVAL;
         }
     }
 
-- 
1.9.1