From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=95.215.58.184 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793861955; b=HQNXG4PIbXZYgftQ9thvQC5W4UT08JZGOOcapc+dXc5YhgWVjTst1nfAk9229IiPRqqG O9vAR40wYrq48y/mG1gp8TbmaUDv0Ole9pnRmgEZNTKQbQ7jiNcpCgHv5tzXPHbkjckBy dUTDK9DenJD9mPUV7UaLiFyLOVS1Ru4+apVUm3x3kQiHho1UwjkK/J9an9G3z4lNvxeyt jXv21VYFYMLgs6XONugruRPw2y89VHJPiMnAa35OCzjAVofe5scO4e6MVbmphIKVTV/+U 5Q0a7xSlGKA4Qh2sisMvahfx4aD/vUfDvXpnoJk9JEaT6CcxB6QJsw/eGHhnC72mT7w== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793861955; h=DMARC-Filter:X-Envelope-To:DKIM-Signature:X-Envelope-To:Received: X-Mizu-Trace-ID:X-Migadu-Flow:From:To:Cc:Subject:Date:Message-ID: X-Mailer:MIME-Version:Content-Transfer-Encoding; bh=8CTBv2FsWWNYoIFrDUziKjer08OPepQNcF8zDvYRVUM=; b=laBIoje764TRaXaMHBJ4s2sb3qNQDTxdkjcAgVY+ydzLXjC49c4v41sRUS2GOsfnsCc0 TSQLKMK7GY7LeGsPTz8n/JBZ6jJkK8OjfOcvWxmp9d9K5rLXBiJfL2yR4Q+HG0xzornMA 2XOslOLmu4S6G9Jt6O89EtBgy2Vbla8/ZeYQpy+EyHPuyFUvaKqJEpGG9m+0oqchO8U/C mMNDtTzme0UMB6N9IOmWLGKJSOyM/CjozaxbF5Ss1HmgeqzC840C1nOokdPtYnWD73zsO LsunjOgZYrSqedWBZS29GSW/S5ZxaMh0YWGKXl9tRPR8FwT2qCLgLnz3ccgrSIpMgrg== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass header.d=linux.dev header.i=@linux.dev header.a=rsa-sha256 header.s=key1 header.b=l+wnEHJf; arc=none smtp.remote-ip=95.215.58.184 Received: from mta1.migadu.com (out-184.mta1.migadu.com [95.215.58.184]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5F259606A328 for ; Thu, 5 Nov 2026 06:59:14 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 5F259606A328 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linux.dev header.i=@linux.dev header.a=rsa-sha256 header.s=key1 header.b=l+wnEHJf X-Envelope-To: linux-kernel@vger.kernel.org DKIM-Signature: a=rsa-sha256; bh=fD7pQ7iJNJUJ2Lt+Fn/kSJBY5hEsxqJHEyhADQZ0hVw=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1793861952; v=1; x=1794466752; b=l+wnEHJf6Oiyr1JLlLvY1SuR55TOc9qTue71B8BOIDVVCSFo+lpfKq7XMsobufkA1UDFYuZg S/4hbx3RQyzDu0U7TxzFT70wLujr3gW8YUSoIvIo9yke829B2TSk5zIlzdtImG9Q4nyXjjfNiiI 9RSLtJX0JrbHg4jDSxSgZSDo= X-Envelope-To: linux-kernel@vger.kernel.org Received: by smtp.migadu.com with ESMTPS id deff676cf379e19e; Thu, 05 Nov 2026 06:59:12 +0000 X-Mizu-Trace-ID: deff676cf379e19e X-Migadu-Flow: FLOW_OUT From: Mengmeng Zhao To: Jens Axboe , Dan Williams , Matthew Wilcox , Jan Kara , Alexander Viro , Christian Brauner , tytso@mit.edu, Andreas Dilger , Baokun Li , Ojaswin Mujoo , "Ritesh Harjani (IBM)" , Zhang Yi , "Darrick J. Wong" , Andrew Morton , asml.silence@gmail.com, hch@lst.de, Anuj Gupta Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, nvdimm@lists.linux.dev, linux-ext4@vger.kernel.org, linux-xfs@vger.kernel.org, linux-mm@kvack.org, Li Wang Subject: [RFC 0/6] ext4: Add dma-buf read/write support Date: Thu, 5 Nov 2026 14:58:41 +0800 Message-ID: <20261105065847.196540-1-mengmeng.zhao@linux.dev> X-Mailer: git-send-email 2.43.0 X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Mengmeng Zhao This series add dma-buf read/write support for ext4. The dma-buf direct I/O infrastructure allows dma-buf to be handed to file I/O as an iov_iter, currently it only supports raw device. To better serve the GPU-NVME direct access through normal filesystem, prior work for XFS has been discussed at [1]. We also are interested in this field and working on it[2]. This patchset is based on Anuj Gupta's patchset as there are common parts at block/iomap. The base tree is: https://github.com/anuj7781/linux-kernel/tree/anuj/fs-dmabuf-rfc-v11-desc-v2 Patches 1-5 add dma-buf guards at several common paths at block, mm/filemap, dax and iomap. Patches 6 add dma-buf support for ext4. [1] https://lore.kernel.org/linux-xfs/20261016091919.971295-1-anuj1072538@gmail.com/ [2] https://lore.kernel.org/all/20260908131545.105987-1-liwang@kylinos.cn/ Mengmeng Zhao (6): block: refuse a dma-buf bio that carries a crypto context mm/filemap: refuse dmabuf iterators in the generic read/write copy paths dax: refuse dmabuf iterators in dax_iomap_rw() iomap: refuse dmabuf iterators in iomap_file_buffered_write() iomap: refuse dmabuf iterators on contents-encrypted inodes ext4: support dma-buf registered buffers for direct I/O block/blk-mq.c | 4 +++- fs/dax.c | 4 ++++ fs/ext4/file.c | 33 +++++++++++++++++++++++++++++++++ fs/iomap/buffered-io.c | 7 +++++++ fs/iomap/direct-io.c | 10 ++++++++++ mm/filemap.c | 22 +++++++++++++++++++++- 6 files changed, 78 insertions(+), 2 deletions(-) -- 2.43.0