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Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Alexei Starovoitov , Daniel Borkmann , Jesper Dangaard Brouer , John Fastabend , Stanislav Fomichev , Willem de Bruijn , Praveen Kaligineedi , Ziwei Xiao , John Fraker , "Dr. David Alan Gilbert" , Ankit Garg , linux-kernel@vger.kernel.org, Jordan Rhee Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Ankit Garg Add support for getting and setting the RX buffer length via the ethtool ring parameters (`ethtool -g`/`-G`). The driver restricts the allowed buffer length to 2048 (SZ_2K) by default and allows 4096 (SZ_4K) based on device options. As XDP is only supported when the `rx_buf_len` is 2048, the driver now enforces this in two places: 1. In `gve_xdp_set`, rejecting XDP programs if the current buffer length is not 2048. 2. In `gve_set_rx_buf_len_config`, rejecting buffer length changes if XDP is loaded and the new length is not 2048. Signed-off-by: Ankit Garg Reviewed-by: Harshitha Ramamurthy Reviewed-by: Jordan Rhee Reviewed-by: Willem de Bruijn Signed-off-by: Joshua Washington --- Changes in v2: * Refactored RX buffer length validation to clarify that it handles scenario when device doesn't advertise 4K support (Jakub Kicinski) --- drivers/net/ethernet/google/gve/gve.h | 9 +++++++++ drivers/net/ethernet/google/gve/gve_ethtool.c | 13 ++++++++++++- drivers/net/ethernet/google/gve/gve_main.c | 39 +++++++++++++++++++++++= ++++++++++++++++ 3 files changed, 60 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/google/gve/gve.h b/drivers/net/ethernet/g= oogle/gve/gve.h index 872dae6..bebd1ac 100644 --- a/drivers/net/ethernet/google/gve/gve.h +++ b/drivers/net/ethernet/google/gve/gve.h @@ -1165,6 +1165,12 @@ static inline bool gve_is_gqi(struct gve_priv *priv) priv->queue_format =3D=3D GVE_GQI_QPL_FORMAT; } +static inline bool gve_is_dqo(struct gve_priv *priv) +{ + return priv->queue_format =3D=3D GVE_DQO_RDA_FORMAT || + priv->queue_format =3D=3D GVE_DQO_QPL_FORMAT; +} + static inline u32 gve_num_tx_queues(struct gve_priv *priv) { return priv->tx_cfg.num_queues + priv->tx_cfg.num_xdp_queues; @@ -1246,6 +1252,9 @@ void gve_rx_free_rings_gqi(struct gve_priv *priv, void gve_rx_start_ring_gqi(struct gve_priv *priv, int idx); void gve_rx_stop_ring_gqi(struct gve_priv *priv, int idx); bool gve_header_split_supported(const struct gve_priv *priv); +int gve_set_rx_buf_len_config(struct gve_priv *priv, u32 rx_buf_len, + struct netlink_ext_ack *extack, + struct gve_rx_alloc_rings_cfg *rx_alloc_cfg); int gve_set_hsplit_config(struct gve_priv *priv, u8 tcp_data_split, struct gve_rx_alloc_rings_cfg *rx_alloc_cfg); /* rx buffer handling */ diff --git a/drivers/net/ethernet/google/gve/gve_ethtool.c b/drivers/net/et= hernet/google/gve/gve_ethtool.c index db6fc85..52500ae 100644 --- a/drivers/net/ethernet/google/gve/gve_ethtool.c +++ b/drivers/net/ethernet/google/gve/gve_ethtool.c @@ -529,6 +529,8 @@ static void gve_get_ringparam(struct net_device *netdev, cmd->rx_pending =3D priv->rx_desc_cnt; cmd->tx_pending =3D priv->tx_desc_cnt; + kernel_cmd->rx_buf_len =3D priv->rx_cfg.packet_buffer_size; + if (!gve_header_split_supported(priv)) kernel_cmd->tcp_data_split =3D ETHTOOL_TCP_DATA_SPLIT_UNKNOWN; else if (priv->header_split_enabled) @@ -589,6 +591,12 @@ static int gve_set_ringparam(struct net_device *netdev, int err; gve_get_curr_alloc_cfgs(priv, &tx_alloc_cfg, &rx_alloc_cfg); + + err =3D gve_set_rx_buf_len_config(priv, kernel_cmd->rx_buf_len, extack, + &rx_alloc_cfg); + if (err) + return err; + err =3D gve_set_hsplit_config(priv, kernel_cmd->tcp_data_split, &rx_alloc_cfg); if (err) @@ -605,6 +613,8 @@ static int gve_set_ringparam(struct net_device *netdev, return err; } else { /* Set ring params for the next up */ + priv->rx_cfg.packet_buffer_size =3D + rx_alloc_cfg.packet_buffer_size; priv->header_split_enabled =3D rx_alloc_cfg.enable_header_split; priv->tx_desc_cnt =3D tx_alloc_cfg.ring_size; priv->rx_desc_cnt =3D rx_alloc_cfg.ring_size; @@ -944,7 +954,8 @@ static int gve_get_ts_info(struct net_device *netdev, const struct ethtool_ops gve_ethtool_ops =3D { .supported_coalesce_params =3D ETHTOOL_COALESCE_USECS, - .supported_ring_params =3D ETHTOOL_RING_USE_TCP_DATA_SPLIT, + .supported_ring_params =3D ETHTOOL_RING_USE_TCP_DATA_SPLIT | + ETHTOOL_RING_USE_RX_BUF_LEN, .get_drvinfo =3D gve_get_drvinfo, .get_strings =3D gve_get_strings, .get_sset_count =3D gve_get_sset_count, diff --git a/drivers/net/ethernet/google/gve/gve_main.c b/drivers/net/ether= net/google/gve/gve_main.c index c1d9916..2a24b3a 100644 --- a/drivers/net/ethernet/google/gve/gve_main.c +++ b/drivers/net/ethernet/google/gve/gve_main.c @@ -1725,6 +1725,13 @@ static int gve_verify_xdp_configuration(struct net_d= evice *dev, return -EOPNOTSUPP; } + if (priv->rx_cfg.packet_buffer_size !=3D SZ_2K) { + NL_SET_ERR_MSG_FMT_MOD(extack, + "XDP is not supported for Rx buf len %d, only %d supported.\n", + priv->rx_cfg.packet_buffer_size, SZ_2K); + return -EOPNOTSUPP; + } + max_xdp_mtu =3D priv->rx_cfg.packet_buffer_size - sizeof(struct ethhdr); if (priv->queue_format =3D=3D GVE_GQI_QPL_FORMAT) max_xdp_mtu -=3D GVE_RX_PAD; @@ -2056,6 +2063,38 @@ bool gve_header_split_supported(const struct gve_pri= v *priv) priv->queue_format =3D=3D GVE_DQO_RDA_FORMAT && !priv->xdp_prog; } +int gve_set_rx_buf_len_config(struct gve_priv *priv, u32 rx_buf_len, + struct netlink_ext_ack *extack, + struct gve_rx_alloc_rings_cfg *rx_alloc_cfg) +{ + u32 old_rx_buf_len =3D rx_alloc_cfg->packet_buffer_size; + + if (rx_buf_len =3D=3D old_rx_buf_len) + return 0; + + /* device options may not always contain support for 4K buffers */ + if (!gve_is_dqo(priv) || priv->max_rx_buffer_size < SZ_4K) { + NL_SET_ERR_MSG_MOD(extack, + "Modifying Rx buf len is not supported"); + return -EOPNOTSUPP; + } + + if (priv->xdp_prog && rx_buf_len !=3D SZ_2K) { + NL_SET_ERR_MSG_MOD(extack, + "Rx buf len can only be 2048 when XDP is on"); + return -EINVAL; + } + + if (rx_buf_len !=3D SZ_2K && rx_buf_len !=3D SZ_4K) { + NL_SET_ERR_MSG_MOD(extack, + "Rx buf len can only be 2048 or 4096"); + return -EINVAL; + } + rx_alloc_cfg->packet_buffer_size =3D rx_buf_len; + + return 0; +} + int gve_set_hsplit_config(struct gve_priv *priv, u8 tcp_data_split, struct gve_rx_alloc_rings_cfg *rx_alloc_cfg) { -- 2.51.2.997.g839fc31de9-goog