From: Edward Cree <[email protected]> Ethtool ntuple filters with FLOW_RSS were originally defined as adding the base queue ID (ring_cookie) to the value from the indirection table, so that the same table could distribute over more than one set of queues when used by different filters. However, some drivers / hardware ignore the ring_cookie, and simply use the indirection table entries as queue IDs directly. Thus, for drivers which have not opted in by setting ethtool_ops.cap_rss_rxnfc_adds to declare that they support the original (addition) semantics, reject in ethtool_set_rxnfc any filter which combines FLOW_RSS and a nonzero ring. (For a ring_cookie of zero, both behaviours are equivalent.) Set the cap bit in sfc, as it is known to support this feature.
Signed-off-by: Edward Cree <[email protected]> --- drivers/net/ethernet/sfc/ef100_ethtool.c | 1 + drivers/net/ethernet/sfc/ethtool.c | 1 + include/linux/ethtool.h | 4 ++++ net/ethtool/ioctl.c | 5 +++++ 4 files changed, 11 insertions(+) diff --git a/drivers/net/ethernet/sfc/ef100_ethtool.c b/drivers/net/ethernet/sfc/ef100_ethtool.c index 5c2551369812..6c3b74000d3b 100644 --- a/drivers/net/ethernet/sfc/ef100_ethtool.c +++ b/drivers/net/ethernet/sfc/ef100_ethtool.c @@ -59,6 +59,7 @@ const struct ethtool_ops ef100_ethtool_ops = { .get_rxfh_indir_size = efx_ethtool_get_rxfh_indir_size, .get_rxfh_key_size = efx_ethtool_get_rxfh_key_size, .rxfh_per_ctx_key = true, + .cap_rss_rxnfc_adds = true, .rxfh_priv_size = sizeof(struct efx_rss_context_priv), .get_rxfh = efx_ethtool_get_rxfh, .set_rxfh = efx_ethtool_set_rxfh, diff --git a/drivers/net/ethernet/sfc/ethtool.c b/drivers/net/ethernet/sfc/ethtool.c index bb1930818beb..83d715544f7f 100644 --- a/drivers/net/ethernet/sfc/ethtool.c +++ b/drivers/net/ethernet/sfc/ethtool.c @@ -263,6 +263,7 @@ const struct ethtool_ops efx_ethtool_ops = { .get_rxfh_indir_size = efx_ethtool_get_rxfh_indir_size, .get_rxfh_key_size = efx_ethtool_get_rxfh_key_size, .rxfh_per_ctx_key = true, + .cap_rss_rxnfc_adds = true, .rxfh_priv_size = sizeof(struct efx_rss_context_priv), .get_rxfh = efx_ethtool_get_rxfh, .set_rxfh = efx_ethtool_set_rxfh, diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h index 1199e308c8dd..299280c94d07 100644 --- a/include/linux/ethtool.h +++ b/include/linux/ethtool.h @@ -734,6 +734,9 @@ struct kernel_ethtool_ts_info { * @rxfh_per_ctx_key: device supports setting different RSS key for each * additional context. Netlink API should report hfunc, key, and input_xfrm * for every context, not just context 0. + * @cap_rss_rxnfc_adds: device supports nonzero ring_cookie in filters with + * %FLOW_RSS flag; the queue ID from the filter is added to the value from + * the indirection table to determine the delivery queue. * @rxfh_indir_space: max size of RSS indirection tables, if indirection table * size as returned by @get_rxfh_indir_size may change during lifetime * of the device. Leave as 0 if the table size is constant. @@ -956,6 +959,7 @@ struct ethtool_ops { u32 cap_rss_ctx_supported:1; u32 cap_rss_sym_xor_supported:1; u32 rxfh_per_ctx_key:1; + u32 cap_rss_rxnfc_adds:1; u32 rxfh_indir_space; u16 rxfh_key_space; u16 rxfh_priv_size; diff --git a/net/ethtool/ioctl.c b/net/ethtool/ioctl.c index 7da94e26ced6..d86399bcf223 100644 --- a/net/ethtool/ioctl.c +++ b/net/ethtool/ioctl.c @@ -992,6 +992,11 @@ static noinline_for_stack int ethtool_set_rxnfc(struct net_device *dev, if (rc) return rc; + /* Nonzero ring with RSS only makes sense if NIC adds them together */ + if (info.flow_type & FLOW_RSS && !ops->cap_rss_rxnfc_adds && + ethtool_get_flow_spec_ring(info.fs.ring_cookie)) + return -EINVAL; + if (ops->get_rxfh) { struct ethtool_rxfh_param rxfh = {};
