From mboxrd@z Thu Jan 1 00:00:00 1970 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 51499C0015E for ; Tue, 1 Aug 2023 13:10:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231933AbjHANKL (ORCPT ); Tue, 1 Aug 2023 09:10:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59472 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231792AbjHANKG (ORCPT ); Tue, 1 Aug 2023 09:10:06 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6CB02E9 for ; Tue, 1 Aug 2023 06:10:05 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 021406159C for ; Tue, 1 Aug 2023 13:10:05 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C08BAC433C7; Tue, 1 Aug 2023 13:10:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1690895404; bh=6Q8lhFvDOVIXoL1/isoX2znCnQ5Jcq/pxYv64+grYik=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=gE4I9ph6RWQ4t6mg9dNeZhZ66dKBYKAjskBqA50lVFDdLdOJD4HwWlyUiaSc9onih MPTBbkUhG6DkrCm+5xNsrkKXEm1/fZoYgVnzpp9iNjsVbskeRgWJ1HmZWPtcAn/rFF wYZvXTHcrzEE5zfDQnKouoQLuy3eo+VQqIhOLt9p74Z5HqIUttdPukIeh33q7rxWNw m8jfJITFviWwZ+C1pffM/jDdYpFCspKIopCc3vLTFB1Rs89BE8hKK6CrsdicmgOLrR /ujU4qZ7puJ6VfWbGNJ5eMu79BMb89Pp4vt1KDcuzX9gldMb2G3j4uufxcF2tj6hL3 5dt+IJzvqd2Ow== From: Christian Brauner Date: Tue, 01 Aug 2023 15:09:01 +0200 Subject: [PATCH RFC 2/3] fs: add vfs_cmd_create() MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20230801-vfs-super-exclusive-v1-2-1a587e56c9f3@kernel.org> References: <20230801-vfs-super-exclusive-v1-0-1a587e56c9f3@kernel.org> In-Reply-To: <20230801-vfs-super-exclusive-v1-0-1a587e56c9f3@kernel.org> To: Jan Kara , Christoph Hellwig Cc: Al Viro , David Howells , Aleksa Sarai , Karel Zak , linux-fsdevel@vger.kernel.org, Christian Brauner X-Mailer: b4 0.13-dev-099c9 X-Developer-Signature: v=1; a=openpgp-sha256; l=1992; i=brauner@kernel.org; h=from:subject:message-id; bh=6Q8lhFvDOVIXoL1/isoX2znCnQ5Jcq/pxYv64+grYik=; b=owGbwMvMwCU28Zj0gdSKO4sYT6slMaScZFG7uM5YP8Z2ncWECQ8k02Lj14vNXOLEXK6vPGnXpIpT znMsOkpZGMS4GGTFFFkc2k3C5ZbzVGw2ytSAmcPKBDKEgYtTACZy8igjw+uClqSp0zSKOLV4vx0td+ 578q/0j+wtl4L2pFOPHOcstmf4yfglL6XgVYgHg8mdjo+vZ9w6HGyhU7V1bYxiHaufg5AbBwA= X-Developer-Key: i=brauner@kernel.org; a=openpgp; fpr=4880B8C9BD0E5106FC070F4F7B3C391EFEA93624 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Split the steps to create a superblock into a tiny helper. This will make the next patch easier to follow. Signed-off-by: Christian Brauner --- fs/fsopen.c | 45 +++++++++++++++++++++++++++++++-------------- 1 file changed, 31 insertions(+), 14 deletions(-) diff --git a/fs/fsopen.c b/fs/fsopen.c index fc9d2d9fd234..af2ff05dcee5 100644 --- a/fs/fsopen.c +++ b/fs/fsopen.c @@ -209,6 +209,36 @@ SYSCALL_DEFINE3(fspick, int, dfd, const char __user *, path, unsigned int, flags return ret; } +static int vfs_cmd_create(struct fs_context *fc) +{ + struct super_block *sb; + int ret; + + if (fc->phase != FS_CONTEXT_CREATE_PARAMS) + return -EBUSY; + + if (!mount_capable(fc)) + return -EPERM; + + fc->phase = FS_CONTEXT_CREATING; + + ret = vfs_get_tree(fc); + if (ret) + return ret; + + sb = fc->root->d_sb; + ret = security_sb_kern_mount(sb); + if (unlikely(ret)) { + fc_drop_locked(fc); + return ret; + } + + /* vfs_get_tree() callchains will have grabbed @s_umount */ + up_write(&sb->s_umount); + fc->phase = FS_CONTEXT_AWAITING_MOUNT; + return 0; +} + /* * Check the state and apply the configuration. Note that this function is * allowed to 'steal' the value by setting param->xxx to NULL before returning. @@ -224,22 +254,9 @@ static int vfs_fsconfig_locked(struct fs_context *fc, int cmd, return ret; switch (cmd) { case FSCONFIG_CMD_CREATE: - if (fc->phase != FS_CONTEXT_CREATE_PARAMS) - return -EBUSY; - if (!mount_capable(fc)) - return -EPERM; - fc->phase = FS_CONTEXT_CREATING; - ret = vfs_get_tree(fc); + ret = vfs_cmd_create(fc); if (ret) break; - sb = fc->root->d_sb; - ret = security_sb_kern_mount(sb); - if (unlikely(ret)) { - fc_drop_locked(fc); - break; - } - up_write(&sb->s_umount); - fc->phase = FS_CONTEXT_AWAITING_MOUNT; return 0; case FSCONFIG_CMD_RECONFIGURE: if (fc->phase != FS_CONTEXT_RECONF_PARAMS) -- 2.34.1