From patchwork Mon Dec 2 16:37:43 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sachin Prabhu X-Patchwork-Id: 3266171 Return-Path: X-Original-To: patchwork-cifs-client@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id B4E1BC0D4A for ; Mon, 2 Dec 2013 16:40:14 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 1E4BD202FF for ; Mon, 2 Dec 2013 16:40:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C80D720279 for ; Mon, 2 Dec 2013 16:40:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752107Ab3LBQkI (ORCPT ); Mon, 2 Dec 2013 11:40:08 -0500 Received: from mx1.redhat.com ([209.132.183.28]:43349 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751964Ab3LBQkH (ORCPT ); Mon, 2 Dec 2013 11:40:07 -0500 Received: from int-mx09.intmail.prod.int.phx2.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id rB2Ge6D8003807 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Mon, 2 Dec 2013 11:40:07 -0500 Received: from sachin-laptop.redhat.com (vpn1-7-112.ams2.redhat.com [10.36.7.112]) by int-mx09.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id rB2Ge4Ce016482 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Mon, 2 Dec 2013 11:40:06 -0500 From: Sachin Prabhu To: linux-cifs Subject: [PATCH 8/8 v3] cifs: Add support for follow_link on dfs shares under posix extensions Date: Mon, 2 Dec 2013 16:37:43 +0000 Message-Id: <1386002263-8630-1-git-send-email-sprabhu@redhat.com> In-Reply-To: <1385399395-19217-1-git-send-email-sprabhu@redhat.com> References: <1385399395-19217-1-git-send-email-sprabhu@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.22 Sender: linux-cifs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-cifs@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP When using posix extensions, dfs shares in the dfs root show up as symlinks resulting in userland tools such as 'ls' calling readlink() on these shares. Since these are dfs shares, we end up returning -EREMOTE. $ ls -l /mnt ls: cannot read symbolic link /mnt/test: Object is remote total 0 lrwxrwxrwx. 1 root root 19 Nov 6 09:47 test With added follow_link() support for dfs shares, when using unix extensions, we call GET_DFS_REFERRAL to obtain the DFS referral and return the first node returned. The dfs share in the dfs root is now displayed in the following manner. $ ls -l /mnt total 0 lrwxrwxrwx. 1 root root 19 Nov 6 09:47 test -> \vm140-31\test Signed-off-by: Sachin Prabhu --- fs/cifs/smb1ops.c | 32 ++++++++++++++++++++++++++++++++ 1 file changed, 32 insertions(+) diff --git a/fs/cifs/smb1ops.c b/fs/cifs/smb1ops.c index 988fddb7..abd2cc9 100644 --- a/fs/cifs/smb1ops.c +++ b/fs/cifs/smb1ops.c @@ -908,6 +908,33 @@ cifs_mand_lock(const unsigned int xid, struct cifsFileInfo *cfile, __u64 offset, } static int +cifs_unix_dfs_readlink(const unsigned int xid, struct cifs_tcon *tcon, + const unsigned char *searchName, char **symlinkinfo, + const struct nls_table *nls_codepage) +{ +#ifdef CONFIG_CIFS_DFS_UPCALL + int rc; + unsigned int num_referrals = 0; + struct dfs_info3_param *referrals = NULL; + + rc = get_dfs_path(xid, tcon->ses, searchName, nls_codepage, + &num_referrals, &referrals, 0); + + if (!rc && num_referrals > 0) { + *symlinkinfo = kstrndup(referrals->node_name, + strlen(referrals->node_name), + GFP_KERNEL); + if (!*symlinkinfo) + rc = -ENOMEM; + free_dfs_info_array(referrals, num_referrals); + } + return rc; +#else /* No DFS support */ + return -EREMOTE; +#endif +} + +static int cifs_query_symlink(const unsigned int xid, struct cifs_tcon *tcon, const char *full_path, char **target_path, struct cifs_sb_info *cifs_sb) @@ -922,6 +949,11 @@ cifs_query_symlink(const unsigned int xid, struct cifs_tcon *tcon, if (cap_unix(tcon->ses)) { rc = CIFSSMBUnixQuerySymLink(xid, tcon, full_path, target_path, cifs_sb->local_nls); + if (rc == -EREMOTE) + rc = cifs_unix_dfs_readlink(xid, tcon, full_path, + target_path, + cifs_sb->local_nls); + goto out; }