From patchwork Thu Feb 27 04:12:06 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mina Almasry X-Patchwork-Id: 13993699 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 4685F20B1E1 for ; Thu, 27 Feb 2025 04:12:21 +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=1740629544; cv=none; b=LszcyQbWKQ0DVfP88IGIaCaGDPpFW5ZpixMdL4lF+ZXeJpTzc/a115Q6YyEk4+0P32VZjT0bE+Lr6ev9EQGPFAV1CioNSTc5hftUKsMlKvZ6cmJ//tkVOAZSi6O3DAO4rw0JednlyHnx0v0zFR5aQjFDuueMp/9x/ixZ+NJniYY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740629544; c=relaxed/simple; bh=6zZjhg68/iYJBRB4m3XZfkrP8wJihUvJUf0RzhlSaaI=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=bA4X9AlD0FqpM2Z/rPRpAvuL9/PrBAD1Ay1IwjMNSKQwrOyu2MDxjjuXxSBgkxIKUEkC7LocbUa4C8EXMltwZl+5VkBcTXsQTsuzMdfb3NiyJRdeJHI4NHSpSmmLfKhFEt5AOKyeC4e8ODaVP/QAJMhdJtu0dqEvjyTralaCpxE= 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=CN45aJTM; 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="CN45aJTM" Received: by mail-pl1-f201.google.com with SMTP id d9443c01a7336-22331df540aso14878685ad.1 for ; Wed, 26 Feb 2025 20:12:21 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1740629540; x=1741234340; 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=Zbf1n5nMrGgkEm8OKJmH1KH6YQxHSldVAhZv8jgHSII=; b=CN45aJTM+YIjTM7yZZ2vCAUBpeFc9QIBvxmHGnOffTn7BPtL7bfHsYRvSxOaMXKFBG w208vf8WQ9lPM4iARqt3APMHfVo1d04PthFJ6wO5Ko9zEKQU39KsRnNm/HDR7eYFXpa5 NmwgCY8znCDRjG/ah6DaW3QZ0Xm66aWJss95RG5R6oK2nN57MLCN1q1CheVzUJXxAUTu 4YtbS7nfMf6rQ0Pyh3n8n8ogCML+xtnCmJsIrMu4LDTbVC+KOR9ui6LVSvANl7cFW0/1 lkgdgPA+zodau8LWc/X1Z4nwautgrvUCEdb9sQ2w+6FxCM8rqYqSADmXp4GEryyl7wGP peQQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1740629540; x=1741234340; 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=Zbf1n5nMrGgkEm8OKJmH1KH6YQxHSldVAhZv8jgHSII=; b=NtMJN7P2+7EMLyPPYkf4xJ+1VLvksTAZbqaNwkJBQhVLOBNORnV2rjydsydJ7M7bU6 ynRsOIhvFB6dNZFEtXliO4+nt/90GkAj5xqTgiF7QeIf1yPRde+ZnIbHzIw99nV7+9CM pAXKU9QB3wn69Tsy5Kfy7KUCg8Ua2pOkM2rlcjO74LzVZfTJHHgPAOLqLuIHLED0LQgU EpjkfAgYq0BrzD+ndMguLTmDLql6BJuEXjc19ctiVqCFMAAhuXCjEVgv3hzKOkLK80hw OAr/AKLeHCudqIMyCk1FhdVg8An8FKo5gTnwEeQhlkNEU/R/vReaCIeVbsaI/ZPv32Zx HaQA== X-Gm-Message-State: AOJu0Yygw8mqN49qGQQcw7sMT1/AJDghHFGfXVaEbIdNzsG1SdKTDZJB /CSQZ4qkSngbby6Y6MfvJjDDXUYSwgaNaR6lP46ORuvEhdp1gI9vD4rpjXylxlhmQyoOo+fmrCJ voQsveM8KC9YenSzLH995uysEUz8IBf65B8JToi1Eha9O6z3KZ/o7aUwvPugzktsEPyLROjzpMv 4V/OHEjdZVHyBrAZ4mix+oq8n7GQiiMw4wmzuNhBQ/IhWlyTRUZ51Ga9wOvBQ= X-Google-Smtp-Source: AGHT+IGDKy2giXtpgwmEdeX2eF65rox8vmx9oiPEONB7TDDjKbzKlZJQAqoYxBHtqGROwp8XHqTNhyRilESKagNMkg== X-Received: from pfbfb34.prod.google.com ([2002:a05:6a00:2da2:b0:730:7485:6b59]) (user=almasrymina job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6a00:2e05:b0:724:59e0:5d22 with SMTP id d2e1a72fcca58-734791b7657mr16917355b3a.20.1740629540276; Wed, 26 Feb 2025 20:12:20 -0800 (PST) Date: Thu, 27 Feb 2025 04:12:06 +0000 In-Reply-To: <20250227041209.2031104-1-almasrymina@google.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20250227041209.2031104-1-almasrymina@google.com> X-Mailer: git-send-email 2.48.1.658.g4767266eb4-goog Message-ID: <20250227041209.2031104-6-almasrymina@google.com> Subject: [PATCH net-next v6 5/8] 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, kvm@vger.kernel.org, virtualization@lists.linux.dev, 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 , "Michael S. Tsirkin" , Jason Wang , Xuan Zhuo , " =?utf-8?q?Eugenio_P=C3=A9rez?= " , Stefan Hajnoczi , Stefano Garzarella , 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 Acked-by: Stanislav Fomichev --- 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 */