From patchwork Tue Feb 28 23:36:10 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Goldwyn Rodrigues X-Patchwork-Id: 9597275 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 6755F600CB for ; Wed, 1 Mar 2017 00:59:10 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 598DE27F7F for ; Wed, 1 Mar 2017 00:59:10 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 4CE1D28490; Wed, 1 Mar 2017 00:59:10 +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=unavailable 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 002A527F7F for ; Wed, 1 Mar 2017 00:59:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751864AbdCAA6f (ORCPT ); Tue, 28 Feb 2017 19:58:35 -0500 Received: from mx2.suse.de ([195.135.220.15]:55555 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751702AbdCAA6c (ORCPT ); Tue, 28 Feb 2017 19:58:32 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay1.suse.de (charybdis-ext.suse.de [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id A2929AD17; Tue, 28 Feb 2017 23:36:53 +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 8/8] nowait aio: btrfs Date: Tue, 28 Feb 2017 17:36:10 -0600 Message-Id: <20170228233610.25456-9-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-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Goldwyn Rodrigues Return EAGAIN if any of the following checks fail + i_rwsem is not lockable + NODATACOW or PREALLOC is not set + Cannot nocow at the desired location + Writing beyond end of file which is not allocated Signed-off-by: Goldwyn Rodrigues --- fs/btrfs/file.c | 25 ++++++++++++++++++++----- fs/btrfs/inode.c | 3 +++ 2 files changed, 23 insertions(+), 5 deletions(-) diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c index b5c5da2..8640280 100644 --- a/fs/btrfs/file.c +++ b/fs/btrfs/file.c @@ -1819,12 +1819,29 @@ static ssize_t btrfs_file_write_iter(struct kiocb *iocb, ssize_t num_written = 0; bool sync = (file->f_flags & O_DSYNC) || IS_SYNC(file->f_mapping->host); ssize_t err; - loff_t pos; - size_t count; + loff_t pos = iocb->ki_pos; + size_t count = iov_iter_count(from); loff_t oldsize; int clean_page = 0; - inode_lock(inode); + if ((iocb->ki_flags & IOCB_NOWAIT) && + (iocb->ki_flags & IOCB_DIRECT)) { + /* Don't sleep on inode rwsem */ + if (!inode_trylock(inode)) + return -EAGAIN; + /* + * We will allocate space in case nodatacow is not set, + * so bail + */ + if (!(BTRFS_I(inode)->flags & (BTRFS_INODE_NODATACOW | + BTRFS_INODE_PREALLOC)) || + check_can_nocow(inode, pos, &count) <= 0) { + inode_unlock(inode); + return -EAGAIN; + } + } else + inode_lock(inode); + err = generic_write_checks(iocb, from); if (err <= 0) { inode_unlock(inode); @@ -1858,8 +1875,6 @@ static ssize_t btrfs_file_write_iter(struct kiocb *iocb, */ update_time_for_write(inode); - pos = iocb->ki_pos; - count = iov_iter_count(from); start_pos = round_down(pos, fs_info->sectorsize); oldsize = i_size_read(inode); if (start_pos > oldsize) { diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 1e861a0..c5041ea 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -8681,6 +8681,9 @@ static ssize_t btrfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter) if (offset + count <= inode->i_size) { inode_unlock(inode); relock = true; + } else if (iocb->ki_flags & IOCB_NOWAIT) { + ret = -EAGAIN; + goto out; } ret = btrfs_delalloc_reserve_space(inode, offset, count); if (ret)