From patchwork Tue Feb 28 23:36:03 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Goldwyn Rodrigues X-Patchwork-Id: 9597167 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 8C25A60429 for ; Wed, 1 Mar 2017 00:01:35 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7E269277D9 for ; Wed, 1 Mar 2017 00:01:35 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 71E3D27FB1; Wed, 1 Mar 2017 00:01:35 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 27AAE277D9 for ; Wed, 1 Mar 2017 00:01:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751704AbdCAABd (ORCPT ); Tue, 28 Feb 2017 19:01:33 -0500 Received: from mx2.suse.de ([195.135.220.15]:52385 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751186AbdB1X7y (ORCPT ); Tue, 28 Feb 2017 18:59:54 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (charybdis-ext.suse.de [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 2A0CFABA2; Tue, 28 Feb 2017 23:36:38 +0000 (UTC) From: Goldwyn Rodrigues To: jack@suse.com Cc: hch@infradead.org, linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-ext4@vger.kernel.org, linux-xfs@vger.kernel.org, Goldwyn Rodrigues Subject: [PATCH 1/8] nowait aio: Introduce IOCB_FLAG_NOWAIT Date: Tue, 28 Feb 2017 17:36:03 -0600 Message-Id: <20170228233610.25456-2-rgoldwyn@suse.de> X-Mailer: git-send-email 2.10.2 In-Reply-To: <20170228233610.25456-1-rgoldwyn@suse.de> References: <20170228233610.25456-1-rgoldwyn@suse.de> Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Goldwyn Rodrigues This flag informs kernel to bail out if an AIO request will block for reasons such as file allocations, or a writeback triggered, or would block while allocating requests while performing direct I/O. IOCB_FLAG_NOWAIT is translated to IOCB_NOWAIT for iocb->ki_flags. Signed-off-by: Goldwyn Rodrigues --- fs/aio.c | 3 +++ include/linux/fs.h | 1 + include/uapi/linux/aio_abi.h | 3 +++ 3 files changed, 7 insertions(+) diff --git a/fs/aio.c b/fs/aio.c index 873b4ca..5ae19ba 100644 --- a/fs/aio.c +++ b/fs/aio.c @@ -1586,6 +1586,9 @@ static int io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb, req->common.ki_flags |= IOCB_EVENTFD; } + if (iocb->aio_flags & IOCB_FLAG_NOWAIT) + req->common.ki_flags |= IOCB_NOWAIT; + ret = put_user(KIOCB_KEY, &user_iocb->aio_key); if (unlikely(ret)) { pr_debug("EFAULT: aio_key\n"); diff --git a/include/linux/fs.h b/include/linux/fs.h index 2ba0743..ab2f556 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -270,6 +270,7 @@ struct writeback_control; #define IOCB_DSYNC (1 << 4) #define IOCB_SYNC (1 << 5) #define IOCB_WRITE (1 << 6) +#define IOCB_NOWAIT (1 << 7) struct kiocb { struct file *ki_filp; diff --git a/include/uapi/linux/aio_abi.h b/include/uapi/linux/aio_abi.h index bb2554f..82d1d94 100644 --- a/include/uapi/linux/aio_abi.h +++ b/include/uapi/linux/aio_abi.h @@ -51,8 +51,11 @@ enum { * * IOCB_FLAG_RESFD - Set if the "aio_resfd" member of the "struct iocb" * is valid. + * IOCB_FLAG_NOWAIT - Set if the user wants the iocb to fail if it would block + * for operations such as disk allocation. */ #define IOCB_FLAG_RESFD (1 << 0) +#define IOCB_FLAG_NOWAIT (1 << 1) /* read() from /dev/aio returns these structures. */ struct io_event {