[Qemu-block] Is the use of bdrv_getlength() in parallels.c kosher? (was: Is the use of bdrv_getlength() in handle_aiocb_write_zeroes() kosher?)

[Markus Armbruster]

Same question for allocate_clusters() in parallels.c, commit 5a41e1f,
modified in commit ddd2ef2:

    if (s->data_end + space > bdrv_getlength(bs->file->bs) >> BDRV_SECTOR_BITS) 
{

bdrv_getlength() can fail.  Does it do the right thing then?  For what
it's worth, the comparison of its value is signed.

There's another one in parallels_open():

    if (!(flags & BDRV_O_RESIZE) || !bdrv_has_zero_init(bs->file->bs) ||
            bdrv_truncate(bs->file, bdrv_getlength(bs->file->bs),
                          PREALLOC_MODE_OFF, NULL) != 0) {
        s->prealloc_mode = PRL_PREALLOC_MODE_FALLOCATE;
    }