diff mbox series

[net-next,1/5] net: ethtool: only allow set_rxnfc with rss + ring_cookie if driver opts in

Message ID cc3da0844083b0e301a33092a6299e4042b65221.1731499022.git.ecree.xilinx@gmail.com (mailing list archive)
State New
Delegated to: Netdev Maintainers
Headers show
Series net: make RSS+RXNFC semantics more explicit | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 8 this patch: 8
netdev/build_tools success Errors and warnings before: 0 (+0) this patch: 0 (+0)
netdev/cc_maintainers warning 1 maintainers not CCed: ahmed.zaki@intel.com
netdev/build_clang success Errors and warnings before: 43 this patch: 43
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 1672 this patch: 1672
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 41 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 5 this patch: 5
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2024-11-14--18-00 (tests: 788)

Commit Message

edward.cree@amd.com Nov. 13, 2024, 12:13 p.m. UTC 
From: Edward Cree <ecree.xilinx@gmail.com>

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 <ecree.xilinx@gmail.com>
---
 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(+)

Comments

Martin Habets Nov. 14, 2024, 9:21 a.m. UTC | #1 
On Wed, Nov 13, 2024 at 12:13:09PM +0000, edward.cree@amd.com wrote:
> 
> From: Edward Cree <ecree.xilinx@gmail.com>
> 
> 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 <ecree.xilinx@gmail.com>

Reviewed-by: Martin Habets <habetsm.xilinx@gmail.com>

> ---
>  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 = {};
>
diff mbox series

Patch

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 = {};