From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0971421A449; Wed, 29 Oct 2025 01:04:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761699841; cv=none; b=XtvBM/hkMS7jr0Mdky6whIvIaGKvJOf74vZMAiv3ZPV3CAXw9TxjTZpwfodeJ6LvqcOXF0Hj+p0lZ/p0+kgAfVgfshQ94xJ4mK5Zp0MvmHLHPHkvBlBD+p//DrJI6P7w0LY+jZWvMHcz5TvPzHnhH/okVLkNus4nt9d4NXS6i4g= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761699841; c=relaxed/simple; bh=yYNO2U77mgEHt6evTRuBoTYo+iD5r6zKJmsafIWfjzg=; h=Date:Subject:From:To:Cc:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=lmPZ5U6z70DeJTSGGq5mbS2MlBWgCjF77BjdAhBwDyLfltRjnaR5t5VAQXDO7IMn61RthK0CIfoicMwsabalGwejlafz+OoFZwKP8Ylvk5mRTXO7ZYf+XXqQHs2l/DBq8Z//+DyiWG6uzEof5+gFMOh4bcxS1q0iX8WlyNDLakw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=pow96vJp; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="pow96vJp" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 74AD9C4CEE7; Wed, 29 Oct 2025 01:04:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1761699840; bh=yYNO2U77mgEHt6evTRuBoTYo+iD5r6zKJmsafIWfjzg=; h=Date:Subject:From:To:Cc:In-Reply-To:References:From; b=pow96vJpPShTAn6r4aFEFhn8Sf+vyQwf9mFmQt6VOOH/zQI+tm5seeU93QVYPdoGP pIQjiTk1aJTnJCXMpQrFT0M2+hk6ymsUZPOoF3jgcOreeIba5SsYM8Q8kSF+ohDdj6 wDgzDtWyzrmTai1K2tW0w3NJwKcpPBEF7/yMjAcEy8eGxG2ntZrsC6r3tPZGffNBZI 0jjrB9rptdOT8EemvRbe5jXvYL/ntoL23m2+GS/c25egzmgQee4/FDpTW0L2ghCiPC Q9AvoAHnosH1Sz3X0ZikE9Z/ljqVlcEc8WHWd0GiC+v9rKNGUxQMIa0KneRUFJOuWV cNJLb4mGmmAIA== Date: Tue, 28 Oct 2025 18:03:59 -0700 Subject: [PATCH 18/22] libfuse: add atomic write support From: "Darrick J. Wong" To: djwong@kernel.org, bschubert@ddn.com Cc: linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org, bernd@bsbernd.com, miklos@szeredi.hu, joannelkoong@gmail.com, neal@gompa.dev Message-ID: <176169813858.1427432.2448355121308876367.stgit@frogsfrogsfrogs> In-Reply-To: <176169813437.1427432.15345189583850708968.stgit@frogsfrogsfrogs> References: <176169813437.1427432.15345189583850708968.stgit@frogsfrogsfrogs> Precedence: bulk X-Mailing-List: linux-ext4@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit From: Darrick J. Wong Add the single flag that we need to turn on atomic write support in fuse. Signed-off-by: "Darrick J. Wong" --- include/fuse_common.h | 4 ++++ include/fuse_kernel.h | 3 +++ lib/fuse_lowlevel.c | 2 ++ 3 files changed, 9 insertions(+) diff --git a/include/fuse_common.h b/include/fuse_common.h index 59b79b44a36e8d..eb08320bc8863f 100644 --- a/include/fuse_common.h +++ b/include/fuse_common.h @@ -540,6 +540,8 @@ struct fuse_loop_config_v1 { * FUSE_IOMAP_SUPPORT_FILEIO: basic file I/O functionality through iomap */ #define FUSE_IOMAP_SUPPORT_FILEIO (1ULL << 0) +/* untorn writes through iomap */ +#define FUSE_IOMAP_SUPPORT_ATOMIC (1ULL << 1) /** * Connection information, passed to the ->init() method @@ -1232,6 +1234,8 @@ static inline bool fuse_iomap_need_write_allocate(unsigned int opflags, #define FUSE_IFLAG_DAX (1U << 0) /* use iomap for this inode */ #define FUSE_IFLAG_IOMAP (1U << 1) +/* enable untorn writes */ +#define FUSE_IFLAG_ATOMIC (1U << 2) /* Which fields are set in fuse_iomap_config_out? */ #define FUSE_IOMAP_CONFIG_SID (1 << 0ULL) diff --git a/include/fuse_kernel.h b/include/fuse_kernel.h index d1143e0c122b9c..5b9259714a628d 100644 --- a/include/fuse_kernel.h +++ b/include/fuse_kernel.h @@ -245,6 +245,7 @@ * - add FUSE_ATTR_IOMAP to enable iomap for specific inodes * - add FUSE_IOMAP_CONFIG so the fuse server can configure more fs geometry * - add FUSE_NOTIFY_IOMAP_DEV_INVAL to invalidate iomap bdev ranges + * - add FUSE_ATTR_ATOMIC for single-fsblock atomic write support */ #ifndef _LINUX_FUSE_H @@ -586,10 +587,12 @@ struct fuse_file_lock { * FUSE_ATTR_SUBMOUNT: Object is a submount root * FUSE_ATTR_DAX: Enable DAX for this file in per inode DAX mode * FUSE_ATTR_IOMAP: Use iomap for this inode + * FUSE_ATTR_ATOMIC: Enable untorn writes */ #define FUSE_ATTR_SUBMOUNT (1 << 0) #define FUSE_ATTR_DAX (1 << 1) #define FUSE_ATTR_IOMAP (1 << 2) +#define FUSE_ATTR_ATOMIC (1 << 3) /** * Open flags diff --git a/lib/fuse_lowlevel.c b/lib/fuse_lowlevel.c index db202b59a2f0e6..605848bb4cd55b 100644 --- a/lib/fuse_lowlevel.c +++ b/lib/fuse_lowlevel.c @@ -127,6 +127,8 @@ static void convert_stat(const struct stat *stbuf, struct fuse_attr *attr, attr->flags |= FUSE_ATTR_DAX; if (iflags & FUSE_IFLAG_IOMAP) attr->flags |= FUSE_ATTR_IOMAP; + if (iflags & FUSE_IFLAG_ATOMIC) + attr->flags |= FUSE_ATTR_ATOMIC; } static void convert_attr(const struct fuse_setattr_in *attr, struct stat *stbuf)