On Sun, Oct 10, 2021 at 09:55:49AM +0300, Gal Pressman wrote: > On 07/10/2021 14:40, Jason Gunthorpe wrote: > > On Thu, Oct 07, 2021 at 01:43:00PM +0300, Gal Pressman wrote: > > > >> @@ -1491,26 +1493,29 @@ static int efa_create_pbl(struct efa_dev *dev, > >> return 0; > >> } > >> > >> -struct ib_mr *efa_reg_mr(struct ib_pd *ibpd, u64 start, u64 length, > >> - u64 virt_addr, int access_flags, > >> - struct ib_udata *udata) > >> +static void efa_dmabuf_invalidate_cb(struct dma_buf_attachment *attach) > >> +{ > >> + WARN_ON_ONCE(1, > >> + "Invalidate callback should not be called when memory is pinned\n"); > >> +} > >> + > >> +static struct dma_buf_attach_ops efa_dmabuf_attach_ops = { > >> + .allow_peer2peer = true, > >> + .move_notify = efa_dmabuf_invalidate_cb, > >> +}; > > > > Shouldn't move_notify really just be left as NULL? I mean fixing > > whatever is preventing that? > > That's what I had in the previous RFC and I think Christian didn't really like it. Well, having drivers define a dummy function that only fails looks a lot worse to me. If not null then it should be a general 'dmabuf_unsupported_move_notify' shared function > >> + err = ib_umem_dmabuf_map_pages(umem_dmabuf); > >> + if (err) { > >> + ibdev_dbg(&dev->ibdev, "Failed to map dmabuf pages\n"); > >> + goto err_unpin; > >> + } > >> + dma_resv_unlock(umem_dmabuf->attach->dmabuf->resv); > > > > If it is really this simple the core code should have this logic, > > 'ib_umem_dmabuf_get_pinned()' or something > > Should get_pinned do just get + dma_buf_pin, or should it do > ib_umem_dmabuf_map_pages as well? Yes the map_pages too, a umem is supposed to be dma mapped after creation. Jason