diff options
Diffstat (limited to 'block.c')
| -rw-r--r-- | block.c | 20 |
1 files changed, 19 insertions, 1 deletions
diff --git a/block.c b/block.c index 0a3d12c328..8a6692719a 100644 --- a/block.c +++ b/block.c @@ -489,7 +489,25 @@ static int bdrv_refresh_limits(BlockDriverState *bs) memset(&bs->bl, 0, sizeof(bs->bl)); - if (drv && drv->bdrv_refresh_limits) { + if (!drv) { + return 0; + } + + /* Take some limits from the children as a default */ + if (bs->file) { + bdrv_refresh_limits(bs->file); + bs->bl.opt_transfer_length = bs->file->bl.opt_transfer_length; + } + + if (bs->backing_hd) { + bdrv_refresh_limits(bs->backing_hd); + bs->bl.opt_transfer_length = + MAX(bs->bl.opt_transfer_length, + bs->backing_hd->bl.opt_transfer_length); + } + + /* Then let the driver override it */ + if (drv->bdrv_refresh_limits) { return drv->bdrv_refresh_limits(bs); } |