From patchwork Thu Jul 15 10:45:31 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitry Kadashev X-Patchwork-Id: 12379825 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8B39AC47E4D for ; Thu, 15 Jul 2021 10:46:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7576361396 for ; Thu, 15 Jul 2021 10:46:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241651AbhGOKs4 (ORCPT ); Thu, 15 Jul 2021 06:48:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58228 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240406AbhGOKsz (ORCPT ); Thu, 15 Jul 2021 06:48:55 -0400 Received: from mail-ej1-x62d.google.com (mail-ej1-x62d.google.com [IPv6:2a00:1450:4864:20::62d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C015BC061760; Thu, 15 Jul 2021 03:46:02 -0700 (PDT) Received: by mail-ej1-x62d.google.com with SMTP id c17so8467447ejk.13; Thu, 15 Jul 2021 03:46:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=0N8efY66+skeToBJjCOx9AdHtvBrjHdTGSW8mN497nw=; b=d/obLiIK4cONRFb3+nisZ4RSwOUnxlbMhbp+atFFDSldraI2mMSeVUlty9vKHT23qg 6Z6V1vp76jALWdH7RnujBAUtpbpO3EA7PcYxWV4OgaLxIynrJk3lF5rsGRjWhdhOK8XS a80sD3bpjkMPPvJe3471PYl/CNjTjIoEO80VGIHWZVLHZDR94CkGj8bRIgrwRT6vQ2mL vEZsECgJFalw6Tx97jgMqpNcJ6dt1t6Zu0YtPksF0NVLqpGTa87JPH/PgjycAlvaE2/B BEHFiiEB7zmvHgnOJPjJDrfR9+2zzyn6B+hcPKDsEKRHemeyH8GxwMqzm9F8/PDBwqDU zvQQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=0N8efY66+skeToBJjCOx9AdHtvBrjHdTGSW8mN497nw=; b=s7t1KLKwfdr0LTXV1PhZ2k7St6e/CuY7UmBq99rHVgLT7XXH8oJA8jSW7TqwNFMxBN cQ28w9yx+/cgEbRadNTZKJEff721mYcN8PdG822NOjw1gl8Rlw8O6BjTTT2qTw2DdAe2 jzQz5oGDbsrSSeixMuc2mhC48QvA1kxqm5pHuNJx4U2/Y1bbDZlC3sSLzdFqOZSPg1dE IJ86GEK15e+j6cUvxv+JGS7vKMbwS3E/2zx2ouvPbyy/OVVJMNnRiFGF5ZseKGf47G6W gDzIB4Mrf77V/Vir+y/ZuE17dpO/RBB9+oHTxcK2p+erYgsPJz51ywRs7kUP2ar7dgxM 4aRA== X-Gm-Message-State: AOAM533pXsnbxfVCGOc12KSj8fOg39ZuZq2o7yjVaPoN0BUZzPzrS2k9 pFFemxFy8lkbBN97RwWTqMk= X-Google-Smtp-Source: ABdhPJzms5OPKKoGFdRkyYUNXdPWeLKCJe3whtABrEsxdh6BLV+G1zRDIqkX1D2rameC5R42flFzng== X-Received: by 2002:a17:906:6b8a:: with SMTP id l10mr4852391ejr.509.1626345961398; Thu, 15 Jul 2021 03:46:01 -0700 (PDT) Received: from carbon.v ([108.61.166.58]) by smtp.googlemail.com with ESMTPSA id d19sm2231498eds.54.2021.07.15.03.46.00 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 15 Jul 2021 03:46:01 -0700 (PDT) From: Dmitry Kadashev To: Jens Axboe , Alexander Viro , Christian Brauner , Linus Torvalds Cc: linux-fsdevel@vger.kernel.org, io-uring@vger.kernel.org, Dmitry Kadashev Subject: [PATCH v2 09/14] namei: prepare do_symlinkat for refactoring Date: Thu, 15 Jul 2021 17:45:31 +0700 Message-Id: <20210715104536.3598130-10-dkadashev@gmail.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210715104536.3598130-1-dkadashev@gmail.com> References: <20210715104536.3598130-1-dkadashev@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org This is just a preparation for the move of the main symlinkat logic to a separate function to make the logic easier to follow. This change contains the flow changes so that the actual change to move the main logic to a separate function does no change the flow at all. There are 3 changes to the flow here: 1. IS_ERR(from) check is repeated on ESTALE retry now. It's OK to do since the call is trivial (and ESTALE retry is a slow path); 2. Just like the similar patches for rmdir and others a few commits before, previously on filename_create() error the function used to exit immediately, and now it will check the return code to see if ESTALE retry is appropriate. The filename_create() does its own retries on ESTALE (at least via filename_parentat() used inside), but this extra check should be completely fine. 3. The retry_estale() check is wrapped in unlikely(). Some other places already have that and overall it seems to make sense Cc: Linus Torvalds Cc: Al Viro Cc: Christian Brauner Suggested-by: Linus Torvalds Link: https://lore.kernel.org/io-uring/CAHk-=wiG+sN+2zSoAOggKCGue2kOJvw3rQySvQXsZstRQFTN+g@mail.gmail.com/ Link: https://lore.kernel.org/io-uring/CAHk-=whH4msnFkj=iYZ9NDmZEAiZKM+vii803M8gnEwEsF1-Yg@mail.gmail.com/ Signed-off-by: Dmitry Kadashev --- fs/namei.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/fs/namei.c b/fs/namei.c index f7cde1543b47..c4d75c94adce 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -4241,15 +4241,15 @@ int do_symlinkat(struct filename *from, int newdfd, struct filename *to) struct path path; unsigned int lookup_flags = 0; +retry: if (IS_ERR(from)) { error = PTR_ERR(from); - goto out_putnames; + goto out; } -retry: dentry = __filename_create(newdfd, to, &path, lookup_flags); error = PTR_ERR(dentry); if (IS_ERR(dentry)) - goto out_putnames; + goto out; error = security_path_symlink(&path, dentry, from->name); if (!error) { @@ -4260,11 +4260,11 @@ int do_symlinkat(struct filename *from, int newdfd, struct filename *to) from->name); } done_path_create(&path, dentry); - if (retry_estale(error, lookup_flags)) { +out: + if (unlikely(retry_estale(error, lookup_flags))) { lookup_flags |= LOOKUP_REVAL; goto retry; } -out_putnames: putname(to); putname(from); return error;