block: Add .bdrv_truncate() error messages

Add missing error messages for the block driver implementations of
.bdrv_truncate(); drop the generic one from block.c's bdrv_truncate().

Since one of these changes touches a mis-indented block in
block/file-posix.c, this patch fixes that coding style issue along the
way.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20170328205129.15138-5-mreitz@redhat.com
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>

1 files changed, 3 insertions, 1 deletions

diff --git a/block/gluster.c b/block/gluster.c
index be45c08b4c..1d4e2f7c52 100644
--- a/block/gluster.c
+++ b/block/gluster.c
@@ -1100,7 +1100,9 @@ static int qemu_gluster_truncate(BlockDriverState *bs, int64_t offset,
 
     ret = glfs_ftruncate(s->fd, offset);
     if (ret < 0) {
-        return -errno;
+        ret = -errno;
+        error_setg_errno(errp, -ret, "Failed to truncate file");
+        return ret;
     }
 
     return 0;