block: Add errp to BD.bdrv_truncate()

Add an Error parameter to the block drivers' bdrv_truncate() interface.
If a block driver does not set this in case of an error, the generic
bdrv_truncate() implementation will do so.

Where it is obvious, this patch also makes some block drivers set this
value.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20170328205129.15138-4-mreitz@redhat.com
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/block.c b/block.c
index 6a1937ead3..ff232a2a20 100644
--- a/block.c
+++ b/block.c
@@ -3328,13 +3328,13 @@ int bdrv_truncate(BdrvChild *child, int64_t offset, Error **errp)
         return -EACCES;
     }
 
-    ret = drv->bdrv_truncate(bs, offset);
+    ret = drv->bdrv_truncate(bs, offset, errp);
     if (ret == 0) {
         ret = refresh_total_sectors(bs, offset >> BDRV_SECTOR_BITS);
         bdrv_dirty_bitmap_truncate(bs);
         bdrv_parent_cb_resize(bs);
         ++bs->write_gen;
-    } else {
+    } else if (errp && !*errp) {
         error_setg_errno(errp, -ret, "Failed to resize image");
     }
     return ret;