From patchwork Sat Feb 22 19:15:14 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mina Almasry X-Patchwork-Id: 13986828 X-Patchwork-Delegate: kuba@kernel.org Received: from mail-pl1-f201.google.com (mail-pl1-f201.google.com [209.85.214.201]) (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 EFA9F21518F for ; Sat, 22 Feb 2025 19:15:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740251733; cv=none; b=u/stqtx75HAoqlOGBhutv56sFvEdcff76zHLP/dN+iCCHAi465Kq+R0g0GikkxfLMNeNlOmJJMNGfNFOY8yMt9uYgDpwPXCuAj0w4YxooFU3KnNsqzM4PCNt3x9RQs+ptQ3gftLhiehFWNTvGYDhrmAKSN4EeLMvmQfSRqZzlLI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740251733; c=relaxed/simple; bh=Z8XZh144o1xsxD6YeKrPk1DFMZATUyG50T5LU7nvHVE=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=mGLs7XAkJL6ljTMTq6t+yWHHgi5l13czwg3yNOndVgdVypyGDxNqUfC/YvWtTHDoP362HAvDDoysWpuPV3m1YZQQMBaBAEhUGW9ig0TA5fMeSoRU8+IGjRFUsur+A1SwFiRR/PdDPw1jVnr3hTr5bXuGY5vEJYbOBIorvf99yjc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--almasrymina.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=YLpWOnlo; arc=none smtp.client-ip=209.85.214.201 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--almasrymina.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="YLpWOnlo" Received: by mail-pl1-f201.google.com with SMTP id d9443c01a7336-220e62c4f27so79229305ad.0 for ; Sat, 22 Feb 2025 11:15:31 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1740251731; x=1740856531; 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=mQstzXvy/+ei25gmEQDC5JMLZS6iH36WD8mnGccBiB0=; b=YLpWOnloljy0bZ6GVd7X/l1j8eL4f5BgvW/OXl+nzmU9yKovA70gSMfmRdGPeNarEK nijqrd+Zhej99wDh7PMNMtRLS6rATXdy0b95M2zo1xrjHpToXcFSSPRnpNTn9GF8Za6N pvJvdaU6J3uLOMBE9ad7xsyqmOrMrRMY0BSW5WfaBCVr7lVo75tkwYZ0lEnWPR8oCzEB shIccDA5UZFrACG4PaHtEhNjStbQtGGhLDkgH7vUvjC8CfZlpdJ2Kc+RxJCOvwLinStL N0ygY2xits2WeabYZGKALD/HnpdRmspM8ZFEe7dzGRaKZY8BfNaWXtj6VBcCNGwtxJRl zlsw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1740251731; x=1740856531; 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=mQstzXvy/+ei25gmEQDC5JMLZS6iH36WD8mnGccBiB0=; b=Pt4PcX8Xc38w8oaAVPrl74s74b0pqh7yubEXgW2k05V7lTTkesHJjhYVvJA7CGWVtU ppjz1bK1yo/u8ioNDSThh2kwnahIAzxfXzU8Osk/9FIuDUYnZ0ImhmcCYtH6Qv3AVbd7 0goPxI1IlC54vyzXPLr0AlRNgWJ4TVnsmqK/R5apdp8EnWuGyHOOXZWEW48eD27IwsSZ 5iPewfDkLPUizEQFqnkTxYolNnVlobvepGN16WH15+C+EwGM6kx9l37Ccx+IDMocN/Mz RAJkCrIQtpHvpA8Z3jfmE4ItIfqDQQVJ1JoGMR6nelz05HcN3rxD8KsBNISZMtdOyqx9 AUHQ== X-Gm-Message-State: AOJu0YyuqOujHnx36KFR5big5d2pRtbVy0LkLHRCrNuehPxYVLIZzWGi vb4fijLA7rmokYK9C7tQ5oADbkO63QQi7x111a1YgYqGMuOmjqYJu1s6mXz+eS+TO3o2mr2wSCA HF/tQu2bPuHPUVDszItXcNIXsvEs0G+10Ri0ylTu8AIe5FVifU3Spvg+VVD3wRwnfMrT0EW7cNi w2HwQxK1ODVe2Es3CDQe8eR7lYrBV9wZwdP/qKXU1rFzS+dyUhuQ7hwJ0x7kc= X-Google-Smtp-Source: AGHT+IGzohye702pra9xAOfuA8QqfT7yOlA9WIo2DniYe4LBDR8mwbdq2/IMdBRMBotzAJAXvPnQ2LHGT+xy2L2BlA== X-Received: from ploo10.prod.google.com ([2002:a17:902:e00a:b0:212:4557:e89b]) (user=almasrymina job=prod-delivery.src-stubby-dispatcher) by 2002:a17:903:191:b0:216:4853:4c0b with SMTP id d9443c01a7336-2219ffc491dmr125988365ad.33.1740251730917; Sat, 22 Feb 2025 11:15:30 -0800 (PST) Date: Sat, 22 Feb 2025 19:15:14 +0000 In-Reply-To: <20250222191517.743530-1-almasrymina@google.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20250222191517.743530-1-almasrymina@google.com> X-Mailer: git-send-email 2.48.1.601.g30ceb7b040-goog Message-ID: <20250222191517.743530-7-almasrymina@google.com> Subject: [PATCH net-next v5 6/9] net: enable driver support for netmem TX From: Mina Almasry To: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, virtualization@lists.linux.dev, kvm@vger.kernel.org, linux-kselftest@vger.kernel.org Cc: Mina Almasry , Donald Hunter , Jakub Kicinski , "David S. Miller" , Eric Dumazet , Paolo Abeni , Simon Horman , Jonathan Corbet , Andrew Lunn , Jeroen de Borst , Harshitha Ramamurthy , Kuniyuki Iwashima , Willem de Bruijn , David Ahern , Neal Cardwell , Stefan Hajnoczi , Stefano Garzarella , "Michael S. Tsirkin" , Jason Wang , Xuan Zhuo , " =?utf-8?q?Eugenio_P=C3=A9rez?= " , Shuah Khan , sdf@fomichev.me, asml.silence@gmail.com, dw@davidwei.uk, Jamal Hadi Salim , Victor Nogueira , Pedro Tammela , Samiullah Khawaja X-Patchwork-Delegate: kuba@kernel.org Drivers need to make sure not to pass netmem dma-addrs to the dma-mapping API in order to support netmem TX. Add helpers and netmem_dma_*() helpers that enables special handling of netmem dma-addrs that drivers can use. Document in netmem.rst what drivers need to do to support netmem TX. Signed-off-by: Mina Almasry --- v5: - Fix netmet TX documentation (Stan). v4: - New patch --- .../networking/net_cachelines/net_device.rst | 1 + Documentation/networking/netdev-features.rst | 5 ++++ Documentation/networking/netmem.rst | 23 +++++++++++++++++-- include/linux/netdevice.h | 2 ++ include/net/netmem.h | 20 ++++++++++++++++ 5 files changed, 49 insertions(+), 2 deletions(-) diff --git a/Documentation/networking/net_cachelines/net_device.rst b/Documentation/networking/net_cachelines/net_device.rst index 15e31ece675f..e3043b033647 100644 --- a/Documentation/networking/net_cachelines/net_device.rst +++ b/Documentation/networking/net_cachelines/net_device.rst @@ -10,6 +10,7 @@ Type Name fastpath_tx_acce =================================== =========================== =================== =================== =================================================================================== unsigned_long:32 priv_flags read_mostly __dev_queue_xmit(tx) unsigned_long:1 lltx read_mostly HARD_TX_LOCK,HARD_TX_TRYLOCK,HARD_TX_UNLOCK(tx) +unsigned long:1 netmem_tx:1; read_mostly char name[16] struct netdev_name_node* name_node struct dev_ifalias* ifalias diff --git a/Documentation/networking/netdev-features.rst b/Documentation/networking/netdev-features.rst index 5014f7cc1398..02bd7536fc0c 100644 --- a/Documentation/networking/netdev-features.rst +++ b/Documentation/networking/netdev-features.rst @@ -188,3 +188,8 @@ Redundancy) frames from one port to another in hardware. This should be set for devices which duplicate outgoing HSR (High-availability Seamless Redundancy) or PRP (Parallel Redundancy Protocol) tags automatically frames in hardware. + +* netmem-tx + +This should be set for devices which support netmem TX. See +Documentation/networking/netmem.rst diff --git a/Documentation/networking/netmem.rst b/Documentation/networking/netmem.rst index 7de21ddb5412..b63aded46337 100644 --- a/Documentation/networking/netmem.rst +++ b/Documentation/networking/netmem.rst @@ -19,8 +19,8 @@ Benefits of Netmem : * Simplified Development: Drivers interact with a consistent API, regardless of the underlying memory implementation. -Driver Requirements -=================== +Driver RX Requirements +====================== 1. The driver must support page_pool. @@ -77,3 +77,22 @@ Driver Requirements that purpose, but be mindful that some netmem types might have longer circulation times, such as when userspace holds a reference in zerocopy scenarios. + +Driver TX Requirements +====================== + +1. The Driver must not pass the netmem dma_addr to any of the dma-mapping APIs + directly. This is because netmem dma_addrs may come from a source like + dma-buf that is not compatible with the dma-mapping APIs. + + Helpers like netmem_dma_unmap_page_attrs() & netmem_dma_unmap_addr_set() + should be used in lieu of dma_unmap_page[_attrs](), dma_unmap_addr_set(). + The netmem variants will handle netmem dma_addrs correctly regardless of the + source, delegating to the dma-mapping APIs when appropriate. + + Not all dma-mapping APIs have netmem equivalents at the moment. If your + driver relies on a missing netmem API, feel free to add and propose to + netdev@, or reach out to the maintainers and/or almasrymina@google.com for + help adding the netmem API. + +2. Driver should declare support by setting `netdev->netmem_tx = true` diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 9a387d456592..22d9621633a0 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -1753,6 +1753,7 @@ enum netdev_reg_state { * @lltx: device supports lockless Tx. Deprecated for real HW * drivers. Mainly used by logical interfaces, such as * bonding and tunnels + * @netmem_tx: device support netmem_tx. * * @name: This is the first field of the "visible" part of this structure * (i.e. as seen by users in the "Space.c" file). It is the name @@ -2061,6 +2062,7 @@ struct net_device { struct_group(priv_flags_fast, unsigned long priv_flags:32; unsigned long lltx:1; + unsigned long netmem_tx:1; ); const struct net_device_ops *netdev_ops; const struct header_ops *header_ops; diff --git a/include/net/netmem.h b/include/net/netmem.h index a2148ffb203d..1fb39ad63290 100644 --- a/include/net/netmem.h +++ b/include/net/netmem.h @@ -8,6 +8,7 @@ #ifndef _NET_NETMEM_H #define _NET_NETMEM_H +#include #include #include @@ -267,4 +268,23 @@ static inline unsigned long netmem_get_dma_addr(netmem_ref netmem) void get_netmem(netmem_ref netmem); void put_netmem(netmem_ref netmem); +#define netmem_dma_unmap_addr_set(NETMEM, PTR, ADDR_NAME, VAL) \ + do { \ + if (!netmem_is_net_iov(NETMEM)) \ + dma_unmap_addr_set(PTR, ADDR_NAME, VAL); \ + else \ + dma_unmap_addr_set(PTR, ADDR_NAME, 0); \ + } while (0) + +static inline void netmem_dma_unmap_page_attrs(struct device *dev, + dma_addr_t addr, size_t size, + enum dma_data_direction dir, + unsigned long attrs) +{ + if (!addr) + return; + + dma_unmap_page_attrs(dev, addr, size, dir, attrs); +} + #endif /* _NET_NETMEM_H */