From patchwork Wed Oct 20 08:29:55 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lorenz Bauer X-Patchwork-Id: 12571827 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 14C06C433FE for ; Wed, 20 Oct 2021 08:30:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 97E0E61359 for ; Wed, 20 Oct 2021 08:30:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229888AbhJTIc2 (ORCPT ); Wed, 20 Oct 2021 04:32:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53238 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229639AbhJTIcW (ORCPT ); Wed, 20 Oct 2021 04:32:22 -0400 Received: from mail-wm1-x333.google.com (mail-wm1-x333.google.com [IPv6:2a00:1450:4864:20::333]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 49AE2C061749 for ; Wed, 20 Oct 2021 01:30:07 -0700 (PDT) Received: by mail-wm1-x333.google.com with SMTP id y74-20020a1c7d4d000000b00322f53b9bbfso9240437wmc.3 for ; Wed, 20 Oct 2021 01:30:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cloudflare.com; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=CbvtrLjcUbfgAMTLROLIlvj1tZ7LmmnXHpndaPRCItA=; b=UCGyUGeVpWan4WCX6U/T8SPsoDfVI8CRM1oqIfsJkpGsZUjZ1PJjuoy0Yx2XdBYhOA FDjDLlXRKmgBMVew3f4H+plLhk3YEnccbeLeSMewyXqwlvLWiTZXI6oGP5do8odiS9yj oG7NPxnJhXvgZTREotbgPMKNA+K7wPzH1puMc= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=CbvtrLjcUbfgAMTLROLIlvj1tZ7LmmnXHpndaPRCItA=; b=bzFjt4zKf8MtmbSKxxW/gVayf588kv1z1qVO82ox8PuCNi38UZKTV6BkvJNA07nrAU 2yMjMNQJPyzVu7IHpbSqeiKDSWlYFXdu2YyZRJZLg/4/skRtxj1Qs3v58kU755/bUjmu cXsKz46bL+D3c1Ny+FWn7MMj5Ve6QjXpA+16zFZnCcCbg35mUD2xc24Y5fkucCJYX/AR N+AdaVYvRUnRp4FHAspvNToiq6YWDlOV2zzZ4BBKPZuTBiwyR1cUo8F2neEs3L9OH+oi ePNb9eAba2EoHV46LUhP393zaTupb9+6GqeQnl7DmHeoNvWdjPOqrL4HC/BuzWfmJoeq yLaQ== X-Gm-Message-State: AOAM531fsYd4kzrhIk9jDVfXMlsRgql3pHrlQJhkx4Cx+t0hFYNVIvre K9OoTbmAA7MDkHXlLh+eNTJEbQ== X-Google-Smtp-Source: ABdhPJyg6rc1ETglY+0y14Mx0eWUrqdIrqIr0lV69WB2xP4oiYg+1LoVvxPsJJ+sjjQmknd4sqwsyQ== X-Received: by 2002:a05:6000:1acc:: with SMTP id i12mr49580282wry.249.1634718605797; Wed, 20 Oct 2021 01:30:05 -0700 (PDT) Received: from antares.. (d.5.c.c.6.2.1.6.f.5.3.5.c.9.c.f.f.f.6.2.a.5.a.7.0.b.8.0.1.0.0.2.ip6.arpa. [2001:8b0:7a5a:26ff:fc9c:535f:6126:cc5d]) by smtp.gmail.com with ESMTPSA id s13sm4473133wmc.47.2021.10.20.01.30.05 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 20 Oct 2021 01:30:05 -0700 (PDT) From: Lorenz Bauer To: Alexander Viro , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko Cc: kernel-team@cloudflare.com, Lorenz Bauer , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, bpf@vger.kernel.org Subject: [PATCH bpf-next 1/2] libfs: support RENAME_EXCHANGE in simple_rename() Date: Wed, 20 Oct 2021 09:29:55 +0100 Message-Id: <20211020082956.8359-2-lmb@cloudflare.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20211020082956.8359-1-lmb@cloudflare.com> References: <20211020082956.8359-1-lmb@cloudflare.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Allow atomic exchange via RENAME_EXCHANGE when using simple_rename. This affects binderfs, ramfs, hubetlbfs and bpffs. There isn't much to do except update the various *time fields. Signed-off-by: Lorenz Bauer --- fs/libfs.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/fs/libfs.c b/fs/libfs.c index 51b4de3b3447..93c03d593749 100644 --- a/fs/libfs.c +++ b/fs/libfs.c @@ -455,9 +455,12 @@ int simple_rename(struct user_namespace *mnt_userns, struct inode *old_dir, struct inode *inode = d_inode(old_dentry); int they_are_dirs = d_is_dir(old_dentry); - if (flags & ~RENAME_NOREPLACE) + if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE)) return -EINVAL; + if (flags & RENAME_EXCHANGE) + goto done; + if (!simple_empty(new_dentry)) return -ENOTEMPTY; @@ -472,6 +475,7 @@ int simple_rename(struct user_namespace *mnt_userns, struct inode *old_dir, inc_nlink(new_dir); } +done: old_dir->i_ctime = old_dir->i_mtime = new_dir->i_ctime = new_dir->i_mtime = inode->i_ctime = current_time(old_dir);