From patchwork Wed Sep 14 06:14:40 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ian Kent X-Patchwork-Id: 9330433 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 26189607FD for ; Wed, 14 Sep 2016 06:15:24 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 169B229941 for ; Wed, 14 Sep 2016 06:15:24 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 0B24829949; Wed, 14 Sep 2016 06:15:24 +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=-6.8 required=2.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_HI,T_DKIM_INVALID 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 9DBBA29941 for ; Wed, 14 Sep 2016 06:15:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758394AbcINGOr (ORCPT ); Wed, 14 Sep 2016 02:14:47 -0400 Received: from out4-smtp.messagingengine.com ([66.111.4.28]:41418 "EHLO out4-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751119AbcINGOo (ORCPT ); Wed, 14 Sep 2016 02:14:44 -0400 Received: from compute7.internal (compute7.nyi.internal [10.202.2.47]) by mailout.nyi.internal (Postfix) with ESMTP id 1BB48203B3; Wed, 14 Sep 2016 02:14:43 -0400 (EDT) Received: from frontend2 ([10.202.2.161]) by compute7.internal (MEProxy); Wed, 14 Sep 2016 02:14:43 -0400 DKIM-Signature: v=1; a=rsa-sha1; c=relaxed/relaxed; d=themaw.net; h=cc :content-transfer-encoding:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to:x-sasl-enc :x-sasl-enc; s=mesmtp; bh=42YgVngwt2IrTPlHMkufeeFEFAk=; b=PoknJD lhdRqBclncWOIi+jFeTQ2oHhsufGd9r24dyJ2+At4w96DeyUk00bZJ2lTXEINjBq 6iksevPHvBYGyM/4JukHEnfrC2uMHmTfLHOsdgCKulrspy7UfPkTxH8lYooLwArO H5/r24nm2D0kuV9v6mTq3SO6Cfyi9FmuAj0PU= DKIM-Signature: v=1; a=rsa-sha1; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-transfer-encoding:content-type :date:from:in-reply-to:message-id:mime-version:references :subject:to:x-sasl-enc:x-sasl-enc; s=smtpout; bh=42YgVngwt2IrTPl HMkufeeFEFAk=; b=mVuBguzfxTF/2zYgrRl6Myf6roQvzuycjfrm+4N0C0H3uxQ TnYAkETGSpaN8J/QS2qcERteb+S8syh0mlFMmP7gGpufC3AfouFshZaeJw1MnHeV vlUgs31fNU3kE4+31UJCcxMx3NL9Jvb4WwxqjUXuLvDNggrOC+zoUEacC0wE= X-Sasl-enc: XUsLBjzlybmt+ThQb/An25jSjEcX5zsLVmh83u/jNg7C 1473833682 Received: from pluto.themaw.net (106-68-162-102.dyn.iinet.net.au [106.68.162.102]) by mail.messagingengine.com (Postfix) with ESMTPA id 7EAA3CCE88; Wed, 14 Sep 2016 02:14:42 -0400 (EDT) Received: from pluto.themaw.net (localhost [127.0.0.1]) by pluto.themaw.net (Postfix) with ESMTP id 10013A0061; Wed, 14 Sep 2016 14:14:40 +0800 (AWST) Subject: [PATCH 2/4] fs - add have_local_submounts() From: Ian Kent To: Andrew Morton Cc: autofs mailing list , Kernel Mailing List , Al Viro , linux-fsdevel , Omar Sandoval , "Eric W. Biederman" Date: Wed, 14 Sep 2016 14:14:40 +0800 Message-ID: <20160914061440.24714.82139.stgit@pluto.themaw.net> In-Reply-To: <20160914061434.24714.490.stgit@pluto.themaw.net> References: <20160914061434.24714.490.stgit@pluto.themaw.net> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The have_submounts() function checks if a dentry is a mountpoint in any namespace but autofs needs to know if the dentry is a mountpoint within the current namespace. Add have_local_submounts() to to do this. Signed-off-by: Ian Kent Cc: Al Viro Cc: Eric W. Biederman Cc: Omar Sandoval --- fs/dcache.c | 34 ++++++++++++++++++++++++++++++++++ include/linux/dcache.h | 1 + 2 files changed, 35 insertions(+) -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/fs/dcache.c b/fs/dcache.c index 5c7cc95..218166b 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -1307,6 +1307,40 @@ int have_submounts(struct dentry *parent) EXPORT_SYMBOL(have_submounts); /* + * Search for at least 1 mount point in the dentry's subdirs. + * We descend to the next level whenever the d_subdirs + * list is non-empty and continue searching. + */ + +static enum d_walk_ret check_local_mount(void *data, struct dentry *dentry) +{ + int *ret = data; + if (is_local_mountpoint(dentry)) { + *ret = 1; + return D_WALK_QUIT; + } + return D_WALK_CONTINUE; +} + +/** + * have_local_submounts - check for mounts over a dentry + * in the current namespace + * @parent: dentry to check. + * + * Return true if the parent or its subdirectories contain + * a mount point + */ +int have_local_submounts(struct dentry *parent) +{ + int ret = 0; + + d_walk(parent, &ret, check_local_mount, NULL); + + return ret; +} +EXPORT_SYMBOL(have_local_submounts); + +/* * Called by mount code to set a mountpoint and check if the mountpoint is * reachable (e.g. NFS can unhash a directory dentry and then the complete * subtree can become unreachable). diff --git a/include/linux/dcache.h b/include/linux/dcache.h index 5ff3e9a..796b358 100644 --- a/include/linux/dcache.h +++ b/include/linux/dcache.h @@ -255,6 +255,7 @@ extern void d_prune_aliases(struct inode *); /* test whether we have any submounts in a subdir tree */ extern int have_submounts(struct dentry *); +extern int have_local_submounts(struct dentry *); /* * This adds the entry to the hash queues.