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, 2 insertions, 0 deletions

diff --git a/block/qcow2.c b/block/qcow2.c
index 6c347989e3..4ca4cf04b0 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -2551,6 +2551,7 @@ static int qcow2_truncate(BlockDriverState *bs, int64_t offset, Error **errp)
     new_l1_size = size_to_l1(s, offset);
     ret = qcow2_grow_l1_table(bs, new_l1_size, true);
     if (ret < 0) {
+        error_setg_errno(errp, -ret, "Failed to grow the L1 table");
         return ret;
     }
 
@@ -2559,6 +2560,7 @@ static int qcow2_truncate(BlockDriverState *bs, int64_t offset, Error **errp)
     ret = bdrv_pwrite_sync(bs->file, offsetof(QCowHeader, size),
                            &offset, sizeof(uint64_t));
     if (ret < 0) {
+        error_setg_errno(errp, -ret, "Failed to update the image size");
         return ret;
     }