From patchwork Fri Aug 25 13:54:13 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hao Xu X-Patchwork-Id: 13365877 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1C55CEE49A6 for ; Fri, 25 Aug 2023 14:01:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245486AbjHYOBY (ORCPT ); Fri, 25 Aug 2023 10:01:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35464 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S245497AbjHYOAz (ORCPT ); Fri, 25 Aug 2023 10:00:55 -0400 Received: from out-244.mta1.migadu.com (out-244.mta1.migadu.com [95.215.58.244]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EA91E269E for ; Fri, 25 Aug 2023 07:00:29 -0700 (PDT) X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1692972015; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=CL8wzJoAbQ75iZcN0EHSqoGXIWt+IFMvEgcKIhs6zqE=; b=UXdbOLDkxTPiI/RUD6vA6Y59upGR8p9yuOS0cheVOmW9wy55dk0PwGqrHNQocUaxtZPqwl 8SMpVuiY/GUEZaQEBzm6P0e4nsRhzT+GENJ6bzTIZGRyqbBvQsF+Q3u8++NZNdyfo398WE Pbto4Fcj8Lgxb50rhsqaYEakh0iY2/E= From: Hao Xu To: io-uring@vger.kernel.org, Jens Axboe Cc: Dominique Martinet , Pavel Begunkov , Christian Brauner , Alexander Viro , Stefan Roesch , Clay Harris , Dave Chinner , "Darrick J . Wong" , linux-fsdevel@vger.kernel.org, linux-xfs@vger.kernel.org, linux-ext4@vger.kernel.org, linux-cachefs@redhat.com, ecryptfs@vger.kernel.org, linux-nfs@vger.kernel.org, linux-unionfs@vger.kernel.org, bpf@vger.kernel.org, netdev@vger.kernel.org, linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, linux-btrfs@vger.kernel.org, codalist@coda.cs.cmu.edu, linux-f2fs-devel@lists.sourceforge.net, cluster-devel@redhat.com, linux-mm@kvack.org, linux-nilfs@vger.kernel.org, devel@lists.orangefs.org, linux-cifs@vger.kernel.org, samba-technical@lists.samba.org, linux-mtd@lists.infradead.org, Wanpeng Li Subject: [PATCH 11/29] vfs: trylock inode->i_rwsem in iterate_dir() to support nowait Date: Fri, 25 Aug 2023 21:54:13 +0800 Message-Id: <20230825135431.1317785-12-hao.xu@linux.dev> In-Reply-To: <20230825135431.1317785-1-hao.xu@linux.dev> References: <20230825135431.1317785-1-hao.xu@linux.dev> MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org From: Hao Xu Trylock inode->i_rwsem in iterate_dir() to support nowait semantics and error out -EAGAIN when there is contention. Signed-off-by: Hao Xu --- fs/readdir.c | 20 ++++++++++++++------ 1 file changed, 14 insertions(+), 6 deletions(-) diff --git a/fs/readdir.c b/fs/readdir.c index 6469f076ba6e..664ecd9665a1 100644 --- a/fs/readdir.c +++ b/fs/readdir.c @@ -43,6 +43,8 @@ int iterate_dir(struct file *file, struct dir_context *ctx) struct inode *inode = file_inode(file); bool shared = false; int res = -ENOTDIR; + bool nowait; + if (file->f_op->iterate_shared) shared = true; else if (!file->f_op->iterate) @@ -52,16 +54,22 @@ int iterate_dir(struct file *file, struct dir_context *ctx) if (res) goto out; - if (shared) - res = down_read_killable(&inode->i_rwsem); - else - res = down_write_killable(&inode->i_rwsem); - if (res) + nowait = ctx->flags & DIR_CONTEXT_F_NOWAIT; + if (nowait) { + res = shared ? down_read_trylock(&inode->i_rwsem) : + down_write_trylock(&inode->i_rwsem); + if (!res) + res = -EAGAIN; + } else { + res = shared ? down_read_killable(&inode->i_rwsem) : + down_write_killable(&inode->i_rwsem); + } + if (res < 0) goto out; res = -ENOENT; if (!IS_DEADDIR(inode)) { - res = file_accessed(file, ctx->flags & DIR_CONTEXT_F_NOWAIT); + res = file_accessed(file, nowait); if (res == -EAGAIN) goto out_unlock;