On Thu, Jul 22, 2021 at 04:22:42PM -0500, Bob Pearson wrote:
> Make changes to rdma_user_rxe.h to allow indexing AH objects, passing
> the index in UD send WRs to the driver and returning the index to the rxe
> provider.
>
> Modify rxe_create_ah() to add an index to AH when created and if
> called from a new user provider return it to user space. If called
> from an old provider mark the AH as not having a useful index.
> Modify rxe_destroy_ah to drop the index before deleting the object.
>
> Signed-off-by: Bob Pearson <rpearsonhpe@xxxxxxxxx>
> drivers/infiniband/sw/rxe/rxe_verbs.c | 31 ++++++++++++++++++++++++++-
> drivers/infiniband/sw/rxe/rxe_verbs.h | 2 ++
> include/uapi/rdma/rdma_user_rxe.h | 8 ++++++-
> 3 files changed, 39 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/infiniband/sw/rxe/rxe_verbs.c b/drivers/infiniband/sw/rxe/rxe_verbs.c
> index 725015a2e84c..7181e21f0c55 100644
> +++ b/drivers/infiniband/sw/rxe/rxe_verbs.c
> @@ -161,9 +161,19 @@ static int rxe_create_ah(struct ib_ah *ibah,
> struct ib_udata *udata)
>
> {
> - int err;
> struct rxe_dev *rxe = to_rdev(ibah->device);
> struct rxe_ah *ah = to_rah(ibah);
> + struct rxe_create_ah_resp __user *uresp = NULL;
> + int err;
> +
> + if (udata) {
> + /* test if new user provider */
> + if (udata->outlen >= sizeof(*uresp))
> + uresp = udata->outbuf;
> + ah->is_user = true;
> + } else {
> + ah->is_user = false;
> + }
>
> err = rxe_av_chk_attr(rxe, init_attr->ah_attr);
> if (err)
> @@ -173,6 +183,24 @@ static int rxe_create_ah(struct ib_ah *ibah,
> if (err)
> return err;
>
> + /* create index > 0 */
> + rxe_add_index(ah);
> + ah->ah_num = ah->pelem.index;
> +
> + if (uresp) {
> + /* only if new user provider */
> + err = copy_to_user(&uresp->ah_num, &ah->ah_num,
> + sizeof(uresp->ah_num));
This should just a using a min_t(size_t udata->outlen, sizeof(*uresp))
And this needs to create the uresp on the stack and copy the whole
thing, not try to copy single values at a time
> diff --git a/drivers/infiniband/sw/rxe/rxe_verbs.h b/drivers/infiniband/sw/rxe/rxe_verbs.h
> index 959a3260fcab..500c47d84500 100644
> +++ b/drivers/infiniband/sw/rxe/rxe_verbs.h
> @@ -48,6 +48,8 @@ struct rxe_ah {
> struct rxe_pool_entry pelem;
> struct rxe_pd *pd;
> struct rxe_av av;
> + bool is_user;
> + int ah_num;
unsigned int?
Jason
