From patchwork Wed May 1 23:15:33 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeremy Bongio X-Patchwork-Id: 1930366 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20230601 header.b=aO9nntvi; dkim-atps=neutral Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=ozlabs.org (client-ip=2404:9400:2221:ea00::3; helo=gandalf.ozlabs.org; envelope-from=srs0=lzpk=me=vger.kernel.org=linux-ext4+bounces-2257-patchwork-incoming=ozlabs.org@ozlabs.org; receiver=patchwork.ozlabs.org) Received: from gandalf.ozlabs.org (mail.ozlabs.org [IPv6:2404:9400:2221:ea00::3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (secp384r1)) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4VVCcr2pnHz23hd for ; Thu, 2 May 2024 09:16:44 +1000 (AEST) Received: from gandalf.ozlabs.org (mail.ozlabs.org [IPv6:2404:9400:2221:ea00::3]) by gandalf.ozlabs.org (Postfix) with ESMTP id 4VVCcr2Jzxz4wcC for ; Thu, 2 May 2024 09:16:44 +1000 (AEST) Received: by gandalf.ozlabs.org (Postfix) id 4VVCcr2Fzdz4wxt; Thu, 2 May 2024 09:16:44 +1000 (AEST) Delivered-To: patchwork-incoming@ozlabs.org Authentication-Results: gandalf.ozlabs.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: gandalf.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20230601 header.b=aO9nntvi; dkim-atps=neutral Authentication-Results: gandalf.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=2604:1380:40f1:3f00::1; helo=sy.mirrors.kernel.org; envelope-from=linux-ext4+bounces-2257-patchwork-incoming=ozlabs.org@vger.kernel.org; receiver=ozlabs.org) Received: from sy.mirrors.kernel.org (sy.mirrors.kernel.org [IPv6:2604:1380:40f1:3f00::1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (No client certificate requested) by gandalf.ozlabs.org (Postfix) with ESMTPS id 4VVCcr225wz4wcC for ; Thu, 2 May 2024 09:16:44 +1000 (AEST) Received: from smtp.subspace.kernel.org (wormhole.subspace.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by sy.mirrors.kernel.org (Postfix) with ESMTPS id 078F5B214B9 for ; Wed, 1 May 2024 23:16:44 +0000 (UTC) Received: from localhost.localdomain (localhost.localdomain [127.0.0.1]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 9CC8F16ABD8; Wed, 1 May 2024 23:16:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="aO9nntvi" X-Original-To: linux-ext4@vger.kernel.org Received: from mail-pf1-f175.google.com (mail-pf1-f175.google.com [209.85.210.175]) (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 15827165FCF; Wed, 1 May 2024 23:16:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.175 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714605386; cv=none; b=G+qvQjXTpzoajh+OQ5lLlGeWmIc8lKetOC9Pq8fHRbnFjXjNeILPkNMNXlcYiMXZooLsjUI7NyIlz6qmEpwphgiZ1dUh59j/CI4VS820uLmANOnG33tm+iJFlngMufCy0iGmK9pjJ6IrCy67dAfFQmSok8GkGgdvpwnBpq3/Zh0= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714605386; c=relaxed/simple; bh=6gk9KXi5PTIE9PO94iveEg+oyKD1+0Jf7RoQi9XALPw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=GgTKkFe58bhbYW5EL8BJ/vSKvB6rOfwjV5eKGhAhGDSKQXLbsHNiDLSk+vWJOl6jMcH5JFlUrVphv8B7FKB2RuRlzD8Hggo7E1VIBO3gwn4bFdCEthw6+HV3F0nKRln9Z98PWmAcjSpX1aaVvvZv4Hcj6utTHb8phHZwbBK235M= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=aO9nntvi; arc=none smtp.client-ip=209.85.210.175 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Received: by mail-pf1-f175.google.com with SMTP id d2e1a72fcca58-6ecff9df447so7033738b3a.1; Wed, 01 May 2024 16:16:24 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1714605384; x=1715210184; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=p9gEegwmgLx+ewZR729FK8KfWn4crXShJOZUZzROTT4=; b=aO9nntvijcdywRMMjmJAIhQBsL8I4NacqDXGGnjZ8kqNBD3Bbd38JQwN+rnV810CNH rGa7RJiBPGrr+NVTxFc6aNGaHdOuusvciWvJPYyIKkH9iOAJNLoFanIdrszkmP705LbT 9MwqmPTRrBBXj2OI7B7l3KemdCEb5hxfM3vBU3IuIkcIz2JVwYDo/m4AmY5cuqeao882 tTK8M/+qS0Fa+NwMKVyynTgO4KKkYnJ06kN1rJ58eteLxPCCiSIWOmcrGqoB7AgU1OlB k2fYAY8RwkTTJg+FpSqF7qfVYQ6/nncRG/3P8JMMyOIiUJwV9CbuIr1t0M6N5j6yXDrK o+uQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1714605384; x=1715210184; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=p9gEegwmgLx+ewZR729FK8KfWn4crXShJOZUZzROTT4=; b=wurdtZ9+MMjpJw3USbPn1zPoObOYIKBVAsBC7nTyxbDZiqB8Yz3LEi2i+wcn/9EeMU XdqNvU9Smfhcne1VBp7J3jJxmRa/lght34d59O8ljFGMSShjtz1hhnGxbBUvwRfwgbEK 7BCfOPt1Pmnbczk1tAJFXps+wou663YNDCnc6cxUSpKQqZCpdyWYjQgdptldhRR17Ola KOmf93nzd3eC/wNnWYGXXHgy/lP8768HVbIeY4Q9cRRZ0jOc2YfhvKwBGawA1rWmysyq PC3/Mgzv0G3KFB4WpqZOb/4IgDXfGzYR0UFkEp+16dIJs8gGQWgoF8qc5hf+PdrpubjN 2rbw== X-Forwarded-Encrypted: i=1; AJvYcCWfT657J59d7CbJObDM9787wYZlhHUa4a3JbzJFIUvHb5jbKjQkDKsriCEsB2jyG/R83Q09jd+jWWet3ZVwjvHUUH4U6k2By5aIaqRJPYfSV4zs0iXau5wvxness2/P3qKlNQKYjIfJANi52L4eUKPGhYNkZX3uD2vKJe+dksEm79cxUV0A X-Gm-Message-State: AOJu0YwL/pmKEG5E8DRQZLA9cMOuvwVAxJI3PRPLPZIcmVY5TxQYfaQ6 YZOJXYJctOVlLDqtUeRvAium/Y5SWJr3h8EwckIiZhS0q2tvfYYU X-Google-Smtp-Source: AGHT+IEso+Eu0Z9Q7uW/sa0iPvg3WM3iY/JkfYstAc2UznW0RvPozenzvmxb0jkOGepLr5DlwbzoFA== X-Received: by 2002:a05:6a00:3d4e:b0:6f3:ef3d:60f3 with SMTP id lp14-20020a056a003d4e00b006f3ef3d60f3mr4496901pfb.29.1714605384318; Wed, 01 May 2024 16:16:24 -0700 (PDT) Received: from jbongio9100214.lan (2606-6000-cfc0-0025-4c92-9b61-6920-c02c.res6.spectrum.com. [2606:6000:cfc0:25:4c92:9b61:6920:c02c]) by smtp.googlemail.com with ESMTPSA id gs18-20020a056a004d9200b006f3fda86d15sm6323389pfb.78.2024.05.01.16.16.23 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 01 May 2024 16:16:23 -0700 (PDT) From: Jeremy Bongio To: Ted Tso Cc: linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-api@vger.kernel.org, linux-block@vger.kernel.org, Jeremy Bongio Subject: [RFC PATCH 1/1] Remove buffered failover for ext4 and block fops direct writes. Date: Wed, 1 May 2024 16:15:33 -0700 Message-ID: <20240501231533.3128797-2-bongiojp@gmail.com> X-Mailer: git-send-email 2.45.0.rc1.225.g2a3ae87e7f-goog In-Reply-To: <20240501231533.3128797-1-bongiojp@gmail.com> References: <20240501231533.3128797-1-bongiojp@gmail.com> Precedence: bulk X-Mailing-List: linux-ext4@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Jeremy Bongio ext4 and block fops would both failover to syncronous, buffered writes if the direct IO results in a short write where only a portion of the request was completed. This patch changes the behavior to simply return the number of bytes written if the direct write is short. --- block/fops.c | 3 --- fs/ext4/file.c | 27 --------------------------- 2 files changed, 30 deletions(-) diff --git a/block/fops.c b/block/fops.c index 0cf8cf72cdfa..d32574ba9d71 100644 --- a/block/fops.c +++ b/block/fops.c @@ -704,9 +704,6 @@ static ssize_t blkdev_write_iter(struct kiocb *iocb, struct iov_iter *from) if (iocb->ki_flags & IOCB_DIRECT) { ret = blkdev_direct_write(iocb, from); - if (ret >= 0 && iov_iter_count(from)) - ret = direct_write_fallback(iocb, from, ret, - blkdev_buffered_write(iocb, from)); } else { ret = blkdev_buffered_write(iocb, from); } diff --git a/fs/ext4/file.c b/fs/ext4/file.c index 54d6ff22585c..d0760452a11f 100644 --- a/fs/ext4/file.c +++ b/fs/ext4/file.c @@ -595,32 +595,6 @@ static ssize_t ext4_dio_write_iter(struct kiocb *iocb, struct iov_iter *from) else inode_unlock(inode); - if (ret >= 0 && iov_iter_count(from)) { - ssize_t err; - loff_t endbyte; - - offset = iocb->ki_pos; - err = ext4_buffered_write_iter(iocb, from); - if (err < 0) - return err; - - /* - * We need to ensure that the pages within the page cache for - * the range covered by this I/O are written to disk and - * invalidated. This is in attempt to preserve the expected - * direct I/O semantics in the case we fallback to buffered I/O - * to complete off the I/O request. - */ - ret += err; - endbyte = offset + err - 1; - err = filemap_write_and_wait_range(iocb->ki_filp->f_mapping, - offset, endbyte); - if (!err) - invalidate_mapping_pages(iocb->ki_filp->f_mapping, - offset >> PAGE_SHIFT, - endbyte >> PAGE_SHIFT); - } - return ret; } @@ -958,4 +932,3 @@ const struct inode_operations ext4_file_inode_operations = { .fileattr_get = ext4_fileattr_get, .fileattr_set = ext4_fileattr_set, }; -