From nobody Fri Dec 19 15:48:17 2025 Received: from mail-pj1-f73.google.com (mail-pj1-f73.google.com [209.85.216.73]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 533403557F6 for ; Thu, 6 Nov 2025 19:28:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.216.73 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762457300; cv=none; b=A+K3d1bQPmOBqAa2X3yUMZ/AYsm8+eCeiIT8HehB/4mc9vQ0hSqmWY5DBM2XlZIt0jdHz27HP6akjxPAHHUOo8rDACw3L6GQyLxspaMxd/4VlB7qgrqg6zSVRgvKIP/ltxRNGTL4WK3umTMAsJwxpfROP89ClfS1/7cibLCs9rs= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762457300; c=relaxed/simple; bh=Xb4EfJdY6bPJY5RRiIfdF/NTZ7iibhgTGr5o3oPF3g4=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=aeQLfULt5oJo6BO59pyuelCajd9VkxI/Hv9srPyrKvxZiEAXOBgiP+GHxFUH+PLTXJs6213SdETD4CDv5Hu6iNgTXSWcUONC3PaK7JGwxiB9kbe3/fnO8r3B6KQwRESWOUQ6+471tAq+BOD0vhZbcr3vYE33xXwv7RX3trJKdyE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--joshwash.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=2nuipWcF; arc=none smtp.client-ip=209.85.216.73 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--joshwash.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="2nuipWcF" Received: by mail-pj1-f73.google.com with SMTP id 98e67ed59e1d1-340bc4ef67fso10459a91.3 for ; Thu, 06 Nov 2025 11:28:18 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1762457297; x=1763062097; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=0JM9jdZzTWd6aLiHrXhH8eGJ9TVRerOe4nqWwRUMVsg=; b=2nuipWcFo49jIv9Iv2llln7A70bCFjYdz1Bk3nKkpbomUK6i9r7zGcu8Mnb2V2xEWc zm0kTah+sYnHqcHtXwnoFjhc7Yt4aYMn600D2awCjouzJeM2GaIhCcr3tAMAOpH0ynA5 p46QszYhZExLydXFxfMgmFdigKiSkHEMEwpUklO8cCDjbhlbaxuc0k97Eqn57rC+uSZS eXJCMK6plNOtoo8IlQInP+BTv+huvLYZPVl9NNDe6SJ6rEMNO1u+l1vf+bYVdkuqZslP r3aGFKnhMN9Z0PnXsRLPYA/59TewJ0/OxtnfEfjfpPxiBk4EzV6zgeMK+xy7sANsGewe N/aw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1762457297; x=1763062097; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=0JM9jdZzTWd6aLiHrXhH8eGJ9TVRerOe4nqWwRUMVsg=; b=OgPMx8rQWezoLCttrt29Tt3lcqCGgaBa4qByvr5fkdmgqWt+PShkBfvWKEXVPEsfl4 vINL+rnwoOi7ffMbqblCIH6LPs681gq205oc10QL+f8he3nbjGSSuhOgKTMat68s818w cPU/6VfqgNTQpFSEVHhFfQx9b/Juf4+QOA6L6EMKSiHnybdp1pU2gs+bzvl4XfXtJ/ZO hb8WkHYEcYVBOW8Ag4CneWuxZ/YQEG8Z0Nh5aF77MN7KM0hs09eYGVHHtEHIVahnhrRt SjHp2P4HdpF/4BG3sQKR0sgLNkxvcbTyk5x5w2WH7Xh0c2+Wg+/4w/1AUMy5Bu+9rWWa zc/g== X-Forwarded-Encrypted: i=1; AJvYcCVEM2Uy1Zd+8b9ohBJoAzFQJd7Rj48mseLgVX0cd+8Q57lZb1EV6eVfA2NFI9yPUNSsO8O/x3whOSWQMiM=@vger.kernel.org X-Gm-Message-State: AOJu0YzxsAtgQXHcxByHRouLCcDgCCAki0+QEaaspRKyczZrCA/mSipt QNntnkGFLi62+tYUim7HU0HwLT1eUawVIWZt2YtVakwBAGVFCAL1dr4pcJFFMHeEfk1A7VH8KpS KRcHfB0xD7a4kDQ== X-Google-Smtp-Source: AGHT+IHGM7JVCPtaPwEFgfbgQR8t2tAo11fskdg8fmXe8PTIoLmsll2rbUTNi7cuelWzWi1tOatyEbKa4QTqwQ== X-Received: from pjty1.prod.google.com ([2002:a17:90a:ca81:b0:33b:51fe:1a89]) (user=joshwash job=prod-delivery.src-stubby-dispatcher) by 2002:a17:90b:3885:b0:340:bb64:c5e with SMTP id 98e67ed59e1d1-3434c4fa855mr370694a91.14.1762457297556; Thu, 06 Nov 2025 11:28:17 -0800 (PST) Date: Thu, 6 Nov 2025 11:27:45 -0800 In-Reply-To: <20251106192746.243525-1-joshwash@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20251106192746.243525-1-joshwash@google.com> X-Mailer: git-send-email 2.51.2.1041.gc1ab5b90ca-goog Message-ID: <20251106192746.243525-4-joshwash@google.com> Subject: [PATCH net-next v3 3/4] gve: Allow ethtool to configure rx_buf_len From: joshwash@google.com To: netdev@vger.kernel.org Cc: Joshua Washington , Harshitha Ramamurthy , Andrew Lunn , "David S. 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, bpf@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 v3: * Removed newline from extack messages (Jakub Kicinski) 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; } =20 +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; =20 + 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; =20 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, =20 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; } =20 + 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.", + 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; } =20 +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) { --=20 2.51.2.997.g839fc31de9-goog