Instead of starting with bio->bi_io_vec, use the offset in bio->bi_idx.
Signed-off-by: "Ed L. Cashin" <ecashin@coraid.com>
Acked-by: Alan Cox <alan@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
        buf->bio = bio;
        buf->resid = bio->bi_size;
        buf->sector = bio->bi_sector;
-       buf->bv = buf->bio->bi_io_vec;
+       buf->bv = &bio->bi_io_vec[bio->bi_idx];
+       WARN_ON(buf->bv->bv_len == 0);
        buf->bv_resid = buf->bv->bv_len;
        buf->bufaddr = page_address(buf->bv->bv_page) + buf->bv->bv_offset;
 
 
                d->inprocess = NULL;
        } else if (buf->bv_resid == 0) {
                buf->bv++;
+               WARN_ON(buf->bv->bv_len == 0);
                buf->bv_resid = buf->bv->bv_len;
                buf->bufaddr = page_address(buf->bv->bv_page) + buf->bv->bv_offset;
        }