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 3A936334C35; Mon, 23 Feb 2026 23:26:09 +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=1771889169; cv=none; b=Z0DsvQ6uBaSdG3TcYgeBbARFGbal+im2elICR1dbO4IxFKkXJTNhTnq9hNZdPVJYyPvHVTnb3Nmx6MThwSi46l7A7Eka5P92Fxwf8PyR8r8pigQDPx78spPq4s8Mub0gIubAnEP9dCt/nj14xUocavlw+j0JMymqxf2jtVBGfTk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771889169; c=relaxed/simple; bh=OCnuwgrlgRu4WxNbNZ4YPew8T7b0+vCWsVKhdzb9NtQ=; h=Date:Subject:From:To:Cc:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=OTAAesZfBVGzEOiJ+O7piMPi8act81OHcbl7+x060bTPyY53O+lptCKKUMnvd58jYzrmv90pW6pG2Bo23Z99m5f/JkE93YNTqG6/GrS7ua+aRxBy7/pTgYZKzT+ZVAXmY0e/dUvAvV6fVWbU//9x80rFW9+L1K1JGTenT6kIkYQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=M66xCcve; 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="M66xCcve" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 17B14C116C6; Mon, 23 Feb 2026 23:26:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1771889169; bh=OCnuwgrlgRu4WxNbNZ4YPew8T7b0+vCWsVKhdzb9NtQ=; h=Date:Subject:From:To:Cc:In-Reply-To:References:From; b=M66xCcved+brKarGkTuWOdbuQ16buQTdcfn1Snd6cmDm6R0Qvc6FkawdGF688AInJ kOGumzNs3lc3Q4BSGE3AzMoJDbUzEa4sUiIbtH5t51Xmrvx4chcG9aUvEpSol92TOV O6GaKZIzwKb2C7tC3XpE3jEdGwaZI9AnAYFbTw18KZeTzFKOI7j6CkScVt1W+/NAZu Fj60y7p61bXYtD1jfVXT27TFHkgIRxQSbB+fEVxFcQPgiJi++lf93qB1bioyPwaxP6 34bmih7vBnI0FRY6JHDyFC46bRWPZJe9Qu3TV3bRy0PsIXI83LN9wMDbMAOU0T12+N 7r5SdKLf91CCg== Date: Mon, 23 Feb 2026 15:26:08 -0800 Subject: [PATCH 03/25] libfuse: add kernel gates for FUSE_IOMAP From: "Darrick J. Wong" To: djwong@kernel.org, bschubert@ddn.com Cc: bernd@bsbernd.com, miklos@szeredi.hu, neal@gompa.dev, linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org, bpf@vger.kernel.org, joannelkoong@gmail.com Message-ID: <177188739992.3940670.1306861107291789968.stgit@frogsfrogsfrogs> In-Reply-To: <177188739839.3940670.15233996351019069073.stgit@frogsfrogsfrogs> References: <177188739839.3940670.15233996351019069073.stgit@frogsfrogsfrogs> Precedence: bulk X-Mailing-List: linux-fsdevel@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 some flags to query and request kernel support for filesystem iomap for regular files. Signed-off-by: "Darrick J. Wong" --- include/fuse_common.h | 5 +++++ include/fuse_kernel.h | 3 +++ lib/fuse_lowlevel.c | 12 +++++++++++- 3 files changed, 19 insertions(+), 1 deletion(-) diff --git a/include/fuse_common.h b/include/fuse_common.h index 041188ec7fa732..9d53354de78868 100644 --- a/include/fuse_common.h +++ b/include/fuse_common.h @@ -512,6 +512,11 @@ struct fuse_loop_config_v1 { */ #define FUSE_CAP_OVER_IO_URING (1UL << 31) +/** + * Client supports using iomap for regular file operations + */ +#define FUSE_CAP_IOMAP (1ULL << 32) + /** * Ioctl flags * diff --git a/include/fuse_kernel.h b/include/fuse_kernel.h index 842cc08a083a6f..354a6da01c2ecc 100644 --- a/include/fuse_kernel.h +++ b/include/fuse_kernel.h @@ -243,6 +243,7 @@ * * 7.99 * - XXX magic minor revision to make experimental code really obvious + * - add FUSE_IOMAP and iomap_{begin,end,ioend} for regular file operations */ #ifndef _LINUX_FUSE_H @@ -451,6 +452,7 @@ struct fuse_file_lock { * FUSE_OVER_IO_URING: Indicate that client supports io-uring * FUSE_REQUEST_TIMEOUT: kernel supports timing out requests. * init_out.request_timeout contains the timeout (in secs) + * FUSE_IOMAP: Client supports iomap for regular file operations */ #define FUSE_ASYNC_READ (1 << 0) #define FUSE_POSIX_LOCKS (1 << 1) @@ -498,6 +500,7 @@ struct fuse_file_lock { #define FUSE_ALLOW_IDMAP (1ULL << 40) #define FUSE_OVER_IO_URING (1ULL << 41) #define FUSE_REQUEST_TIMEOUT (1ULL << 42) +#define FUSE_IOMAP (1ULL << 43) /** * CUSE INIT request/reply flags diff --git a/lib/fuse_lowlevel.c b/lib/fuse_lowlevel.c index c3d57f5c5b104c..237c02c6dce7d5 100644 --- a/lib/fuse_lowlevel.c +++ b/lib/fuse_lowlevel.c @@ -2817,7 +2817,10 @@ _do_init(fuse_req_t req, const fuse_ino_t nodeid, const void *op_in, se->conn.capable_ext |= FUSE_CAP_NO_EXPORT_SUPPORT; if (inargflags & FUSE_OVER_IO_URING) se->conn.capable_ext |= FUSE_CAP_OVER_IO_URING; - + if (inargflags & FUSE_IOMAP) + se->conn.capable_ext |= FUSE_CAP_IOMAP; + /* Don't let anyone touch iomap until the end of the patchset. */ + se->conn.capable_ext &= ~FUSE_CAP_IOMAP; } else { se->conn.max_readahead = 0; } @@ -2863,6 +2866,9 @@ _do_init(fuse_req_t req, const fuse_ino_t nodeid, const void *op_in, FUSE_CAP_READDIRPLUS_AUTO); LL_SET_DEFAULT(1, FUSE_CAP_OVER_IO_URING); + /* servers need to opt-in to iomap explicitly */ + LL_SET_DEFAULT(0, FUSE_CAP_IOMAP); + /* This could safely become default, but libfuse needs an API extension * to support it * LL_SET_DEFAULT(1, FUSE_CAP_SETXATTR_EXT); @@ -2980,6 +2986,8 @@ _do_init(fuse_req_t req, const fuse_ino_t nodeid, const void *op_in, outargflags |= FUSE_REQUEST_TIMEOUT; outarg.request_timeout = se->conn.request_timeout; } + if (se->conn.want_ext & FUSE_CAP_IOMAP) + outargflags |= FUSE_IOMAP; outarg.max_readahead = se->conn.max_readahead; outarg.max_write = se->conn.max_write; @@ -3014,6 +3022,8 @@ _do_init(fuse_req_t req, const fuse_ino_t nodeid, const void *op_in, if (se->conn.want_ext & FUSE_CAP_PASSTHROUGH) fuse_log(FUSE_LOG_DEBUG, " max_stack_depth=%u\n", outarg.max_stack_depth); + if (se->conn.want_ext & FUSE_CAP_IOMAP) + fuse_log(FUSE_LOG_DEBUG, " iomap=1\n"); } if (arg->minor < 5) outargsize = FUSE_COMPAT_INIT_OUT_SIZE;