> -----Original Message-----
> From: Chuck Lever <cel@xxxxxxxxxx>
> Sent: Thursday, 27 April 2023 19:15
> To: Bernard Metzler <BMT@xxxxxxxxxxxxxx>
> Cc: linux-rdma@xxxxxxxxxxxxxxx; linux-nfs@xxxxxxxxxxxxxxx
> Subject: [EXTERNAL] [PATCH RFC] RDMA/core: Store zero GIDs in some cases
>
> From: Bernard Metzler <bmt@xxxxxxxxxxxxxx>
>
> Tunnel devices have zero GIDs, so skip the zero GID check when
> setting up soft iWARP over a tunnel device.
>
> Suggested-by: Bernard Metzler <bmt@xxxxxxxxxxxxxx>
> Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
> ---
> drivers/infiniband/core/cache.c | 4 +++-
> drivers/infiniband/sw/siw/siw_main.c | 1 +
> include/rdma/iw_cm.h | 9 ++++++++-
> 3 files changed, 12 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/infiniband/core/cache.c
> b/drivers/infiniband/core/cache.c
> index 2e91d8879326..2493ca4f2739 100644
> --- a/drivers/infiniband/core/cache.c
> +++ b/drivers/infiniband/core/cache.c
> @@ -41,6 +41,7 @@
> #include <net/addrconf.h>
>
> #include <rdma/ib_cache.h>
> +#include <rdma/iw_cm.h>
>
> #include "core_priv.h"
>
> @@ -441,7 +442,8 @@ static int add_modify_gid(struct ib_gid_table *table,
> * leave other unused entries as the zero GID. Convert zero GIDs to
> * empty table entries instead of storing them.
> */
> - if (rdma_is_zero_gid(&attr->gid))
> + if (rdma_is_zero_gid(&attr->gid) &&
> + !(attr->device->iw_driver_flags & IW_F_STORE_0GID))
> return 0;
>
> entry = alloc_gid_entry(attr);
> diff --git a/drivers/infiniband/sw/siw/siw_main.c
> b/drivers/infiniband/sw/siw/siw_main.c
> index dacc174604bf..842a039fa457 100644
> --- a/drivers/infiniband/sw/siw/siw_main.c
> +++ b/drivers/infiniband/sw/siw/siw_main.c
> @@ -359,6 +359,7 @@ static struct siw_device *siw_device_create(struct
> net_device *netdev)
>
> /* Disable TCP port mapping */
> base_dev->iw_driver_flags = IW_F_NO_PORT_MAP;
> + base_dev->iw_driver_flags = IW_F_STORE_0GID;
>
That overwrites the first assignment. Probably better
'|= IW_F_STORE_0GID;' ? Or put them on one line...
> sdev->attrs.max_qp = SIW_MAX_QP;
> sdev->attrs.max_qp_wr = SIW_MAX_QP_WR;
> diff --git a/include/rdma/iw_cm.h b/include/rdma/iw_cm.h
> index 03abd30e6c8c..c48f2cbe37b5 100644
> --- a/include/rdma/iw_cm.h
> +++ b/include/rdma/iw_cm.h
> @@ -90,7 +90,14 @@ enum iw_flags {
> * reserve the port. This is required for soft iwarp
> * to play in the port mapped iwarp space.
> */
> - IW_F_NO_PORT_MAP = (1 << 0),
> + IW_F_NO_PORT_MAP = BIT(0),
> +
> + /*
> + * This flag allows the insertion of zero GIDs into the
> + * stored GID table. That is needed to enable soft iWARP
> + * on tunnel devices.
> + */
> + IW_F_STORE_0GID = BIT(1),
> };
>
> /**
>
