From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oi1-f170.google.com (mail-oi1-f170.google.com [209.85.167.170]) (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 838A53947A4 for ; Wed, 1 Jul 2026 18:42:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=pass smtp.client-ip=209.85.167.170 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782931379; cv=pass; b=CMwn1hE5XyI7iB2zUhQN1rGsvexIQrMDS+yljKx4W2s7jlpW75exFpBhJw1k2wqE5P7ATmRPuf7/9o9y9MCQFAWpnQ4/XHa5ecMgDIsEX+QGSANMpXTHjkgubQDCrP4URJWEQxdNMD22kC2J4d/2Plk+7cD8JXXiJsqNMDaztkQ= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782931379; c=relaxed/simple; bh=dtn2YffXfDyR5hZVMmhNG75JP/ICDogzGJzK452Phz0=; h=MIME-Version:References:In-Reply-To:From:Date:Message-ID:Subject: To:Cc:Content-Type; b=EePpDCRZjjo+skciO2XvZOarrFHtrnaGpE39fgfmphmSQ6wK7evcz38Pet41vbQHzs2IutkH+vBCZAQG6TLcGFYLLQxflXcmOX1r0CkZhUuG4HLaqzrpljjA73jAkKhwHLGk/bhdLp6GUlbU+W5PEbJkx8k4ZKQe1uggNjLFwRo= ARC-Authentication-Results:i=2; 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=FDixXHgF; arc=pass smtp.client-ip=209.85.167.170 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 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="FDixXHgF" Received: by mail-oi1-f170.google.com with SMTP id 5614622812f47-495c63c41ceso482120b6e.2 for ; Wed, 01 Jul 2026 11:42:58 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1782931377; cv=none; d=google.com; s=arc-20260327; b=hMFRT6UrzpeLonpdIawR0gELM+meOGwvYzZU6SCrlSQDA8ye0ckbbo/inKMjjP+bH1 d3vxiwmPRR164laC8ZoC2g6vlUqtrNF1EPtD/CemPw7JJUaIB6HVP0Qa5hdumRH/E6hV bSfSoK2FJaLYdWnBF1GLG+/aVMZILcGY2x/WGucy4wM/TOqjTGWcXQ4T+lU7tyrsRVSE O6qZdhBMmXqhY957/XMQR8i/pcuD6Pz6eXDs5CSHyGhq19bM37t9XNXejX1UBmFJ1iCL tjaZIFlbWHyJLY2SPKVOR0F2cn47v0zCmy/WjfrG+T6WTRNiqi/FO2dqqbOy2aGJNKkG Syag== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20260327; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:dkim-signature; bh=YNo4H7B94p9nhYVyAQkHxg75frg7eF2HSh8OUMRCG+Y=; fh=8vlNUM2voGqUrRxX8gtu7otAF+pNbAA4ida3YwYUhLY=; b=hDjrALGluw/a261O64PR2ryo/RYE27zNMxwxb23keDwVcEd0qsKWmTZRsuDmDG9SlK ZWFFG8cYeypDSHXdPtO9vbJkKrpq46ZRYrymceZBJWwE24emD7Gc3lLKONa59yynfEd6 UmVVgPbH3IRIo4SThCRWF8rWTP51AOKUXZCGshc8VbmLb41rxRAW5hBlhU2H8GWI8TML sAHHwqUtIejRz/NsvyA6FoJ6D3aa4jJRx3rGmq2MA+I/PS4OCVprAl7BbtH+CASJRZ82 3YzXzfgQSH8tjAo8qEhDtIwDDfVhdJQ4qpE4dfYY5Xz6NOQ7Q2AoemVUQk9n4K0EiTsP t6Cg==; darn=vger.kernel.org ARC-Authentication-Results: i=1; mx.google.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1782931377; x=1783536177; darn=vger.kernel.org; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=YNo4H7B94p9nhYVyAQkHxg75frg7eF2HSh8OUMRCG+Y=; b=FDixXHgFs+cf2aHLypYYykq7tCxVtKhUWUOTr+Y3uScq1zjvYdaP7f9uw2UYsAxZuA m82cfb5UF3lzqmHz4qjIZvwpiplGLQV+Tqd7qEGpnY36GKhEJmdQ9zS5EwmYt+s9kZAx l5YKm7feJKZOammoSqOmVm93iaL0v2BBjNtlrz5VScGRNqf7sFOFBumOqxiXApKZo/Oi ANCNGFw27ekbvmLx9CbU8Uy81NsWWslz1/inKz/OEzdxUWDpF0oUD2O9hh0k5HTY6W+m SdwG1dhIq56uAVEBNT2g5d6bIBVeD+yvBT7KkunYVDugh4Aozu3kVf3DE1/4xjUNczPX JKOw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1782931377; x=1783536177; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to; bh=YNo4H7B94p9nhYVyAQkHxg75frg7eF2HSh8OUMRCG+Y=; b=gOiedlA8jhGc2HwVdnn2Ic9ViMFS1ph2XVNsJjv9J2FzN3epKAYvqMKYSM2gJ3Bo7e 4Fo6u5FJBXK1cAjH2ckdGDpcOxK5KrtHu3Kzcm7It7r3C2xzodvBhE6tR5dQ2eX58M+x GEO98Dg/6Q7B7VEjJUOT6fQY8aNXryws4ZkFbMMMR+DSpQzrBF3a8Bl6jAdGuxGMxX8a /AVcmPgwWS5Ct74Ym6HF9/62+vvICcfNSfQGTosN9oYDdEl0SfkYm8O1ymMfR9i5lS6M 1ozNjERbCBO6CKXI9xROUwFEPC6lqGC+Wu8Cx1BAOh2DWi7eFOk+Wwg00vB72Qz0sgx3 XU9w== X-Forwarded-Encrypted: i=1; AFNElJ/IxuqJXZ3parnjaL5t8VXhBHLwuxJ7pYQOPC2mUtmqcrc8c/UzOUTBwHgjUZs+FiNsOLWeoB4BEHDHhBc=@vger.kernel.org X-Gm-Message-State: AOJu0YwXiuh9ltIQutt3mtOcVktS20bfgcTLhMpLeYD3q39//LNgyZp6 XRs0zwBo5xHKXJ7Zlmz5Aowh9upf7qrSqd4c/ewcLQCgdT68BqShrQn8sXju83WRAcerAlQydVo JD+qWlJrcRpEatpt041DbUpPUtun1Lck= X-Gm-Gg: AfdE7cmYFFH3BraKKAutg5MigC2eXe6b/kJX79Ijj9DtwmOHe1zk+hj5kbc1Ej9scwX E5eMgTxyKSIk7ih0iaDLvUO3UFqKGU6eYMju1c1lnIx+tA3yl8gfNh6U7g2Fx6PQjBjm3CRhop7 6y2/nrFAI1kXbR2PNo3fz+ICvAk6zoAvISMOibWjXib/itXGdy5ZR3IpixAwy+oiqSzaLoghGWy 7GhavU5g1RSee3EoOvcYQJHhzZcmUJx3wcc0ixijVwDLzBXaNihQpwsTWhOIXTAqPGeBqZO X-Received: by 2002:a05:6808:1508:b0:491:3ade:8ba0 with SMTP id 5614622812f47-4960ee01b26mr1888600b6e.16.1782931377482; Wed, 01 Jul 2026 11:42:57 -0700 (PDT) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 References: <44e53f18f7bc7d190c2676e66a0b77a40a62d448.1782619718.git.jbingham@gmail.com> <20260701182146.GD6507@frogsfrogsfrogs> In-Reply-To: <20260701182146.GD6507@frogsfrogsfrogs> From: Jeremy Bingham Date: Wed, 1 Jul 2026 11:42:45 -0700 X-Gm-Features: AVVi8Ccx7043s48-Csvz6w-YG14hk-GhZUaghEDj8Vlr68E5PdG8KlquygtL-G8 Message-ID: Subject: Re: [PATCH v2 3/4] minix: convert file operations to iomap and add To: "Darrick J. Wong" Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, brauner@kernel.org, jkoolstra@xs4all.nl, jack@suse.cz, hch@infradead.org, viro@zeniv.linux.org.uk, syzkaller@googlegroups.com Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Wed, Jul 1, 2026 at 11:21=E2=80=AFAM Darrick J. Wong = wrote: > > On Sat, Jun 27, 2026 at 10:15:55PM -0700, Jeremy Bingham wrote: > > Subject: [PATCH v2 3/4] minix: convert file operations to iomap and add > > ...add what? Ugh, "add direct I/O". When I was preparing the second version of the patch= es, I screwed up. > > Replace generic_file_read_iter and generic_file_write_iter with custom > > minix_file_read_iter and minix_file_write_iter that dispatch to iomap > > for both buffered and direct I/O. > > > > Buffered writes now go through iomap_file_buffered_write instead of > > the aops write_begin/write_end path (which no longer exists for > > regular files). Buffered reads still use generic_file_read_iter > > for the non-DIO case. > > > > Direct I/O is implemented via iomap_dio_rw for both reads and writes. > > minix_dio_read_iter takes a shared inode lock; minix_dio_write_iter > > takes an exclusive lock, does generic_write_checks, and falls back > > to buffered writes via iomap_file_buffered_write for the tail of a > > DIO write that is not block-aligned. The minix_dio_write_end_io > > callback updates i_size and marks the inode dirty. > > > > minix_file_open sets FMODE_CAN_ODIRECT so the VFS allows O_DIRECT > > opens, and splice_write is added to the file operations. > > Ignore my question about FMODE_CAN_ODIRECT in the previous patch, then. Noted. > > + > > + if (ret >=3D 0 && iov_iter_count(from)) { > > + loff_t pos; > > + loff_t endbyte; > > + ssize_t status; > > + > > + iocb->ki_flags &=3D ~IOCB_DIRECT; > > Why not set IOC_DSYNC here and let generic_write_sync do all the > flushing work for you? There's no requirement to dump the pagecache > after a downgraded direct write, but if you want that, use > IOCB_DONTCACHE. > > --D *nod* I will also try this when I'm updating the minix patches. Thank you again for your comments, -j