Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 4832 insertions, 0 deletions

diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
new file mode 100644
index 000000000..b5aba1c89
--- /dev/null
+++ b/fs/cifs/connect.c
@@ -0,0 +1,4832 @@
+/*
+ *   fs/cifs/connect.c
+ *
+ *   Copyright (C) International Business Machines  Corp., 2002,2011
+ *   Author(s): Steve French (sfrench@us.ibm.com)
+ *
+ *   This library is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU Lesser General Public License as published
+ *   by the Free Software Foundation; either version 2.1 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This library is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
+ *   the GNU Lesser General Public License for more details.
+ *
+ *   You should have received a copy of the GNU Lesser General Public License
+ *   along with this library; if not, write to the Free Software
+ *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+#include <linux/fs.h>
+#include <linux/net.h>
+#include <linux/string.h>
+#include <linux/sched/signal.h>
+#include <linux/list.h>
+#include <linux/wait.h>
+#include <linux/slab.h>
+#include <linux/pagemap.h>
+#include <linux/ctype.h>
+#include <linux/utsname.h>
+#include <linux/mempool.h>
+#include <linux/delay.h>
+#include <linux/completion.h>
+#include <linux/kthread.h>
+#include <linux/pagevec.h>
+#include <linux/freezer.h>
+#include <linux/namei.h>
+#include <linux/uuid.h>
+#include <linux/uaccess.h>
+#include <asm/processor.h>
+#include <linux/inet.h>
+#include <linux/module.h>
+#include <keys/user-type.h>
+#include <net/ipv6.h>
+#include <linux/parser.h>
+#include <linux/bvec.h>
+#include "cifspdu.h"
+#include "cifsglob.h"
+#include "cifsproto.h"
+#include "cifs_unicode.h"
+#include "cifs_debug.h"
+#include "cifs_fs_sb.h"
+#include "dns_resolve.h"
+#include "ntlmssp.h"
+#include "nterr.h"
+#include "rfc1002pdu.h"
+#include "fscache.h"
+#include "smb2proto.h"
+#include "smbdirect.h"
+
+extern mempool_t *cifs_req_poolp;
+extern bool disable_legacy_dialects;
+
+/* FIXME: should these be tunable? */
+#define TLINK_ERROR_EXPIRE	(1 * HZ)
+#define TLINK_IDLE_EXPIRE	(600 * HZ)
+
+enum {
+	/* Mount options that take no arguments */
+	Opt_user_xattr, Opt_nouser_xattr,
+	Opt_forceuid, Opt_noforceuid,
+	Opt_forcegid, Opt_noforcegid,
+	Opt_noblocksend, Opt_noautotune, Opt_nolease,
+	Opt_hard, Opt_soft, Opt_perm, Opt_noperm,
+	Opt_mapposix, Opt_nomapposix,
+	Opt_mapchars, Opt_nomapchars, Opt_sfu,
+	Opt_nosfu, Opt_nodfs, Opt_posixpaths,
+	Opt_noposixpaths, Opt_nounix, Opt_unix,
+	Opt_nocase,
+	Opt_brl, Opt_nobrl,
+	Opt_handlecache, Opt_nohandlecache,
+	Opt_forcemandatorylock, Opt_setuidfromacl, Opt_setuids,
+	Opt_nosetuids, Opt_dynperm, Opt_nodynperm,
+	Opt_nohard, Opt_nosoft,
+	Opt_nointr, Opt_intr,
+	Opt_nostrictsync, Opt_strictsync,
+	Opt_serverino, Opt_noserverino,
+	Opt_rwpidforward, Opt_cifsacl, Opt_nocifsacl,
+	Opt_acl, Opt_noacl, Opt_locallease,
+	Opt_sign, Opt_seal, Opt_noac,
+	Opt_fsc, Opt_mfsymlinks,
+	Opt_multiuser, Opt_sloppy, Opt_nosharesock,
+	Opt_persistent, Opt_nopersistent,
+	Opt_resilient, Opt_noresilient,
+	Opt_domainauto, Opt_rdma,
+
+	/* Mount options which take numeric value */
+	Opt_backupuid, Opt_backupgid, Opt_uid,
+	Opt_cruid, Opt_gid, Opt_file_mode,
+	Opt_dirmode, Opt_port,
+	Opt_rsize, Opt_wsize, Opt_actimeo,
+	Opt_echo_interval, Opt_max_credits,
+	Opt_snapshot,
+
+	/* Mount options which take string value */
+	Opt_user, Opt_pass, Opt_ip,
+	Opt_domain, Opt_srcaddr, Opt_iocharset,
+	Opt_netbiosname, Opt_servern,
+	Opt_ver, Opt_vers, Opt_sec, Opt_cache,
+
+	/* Mount options to be ignored */
+	Opt_ignore,
+
+	/* Options which could be blank */
+	Opt_blank_pass,
+	Opt_blank_user,
+	Opt_blank_ip,
+
+	Opt_err
+};
+
+static const match_table_t cifs_mount_option_tokens = {
+
+	{ Opt_user_xattr, "user_xattr" },
+	{ Opt_nouser_xattr, "nouser_xattr" },
+	{ Opt_forceuid, "forceuid" },
+	{ Opt_noforceuid, "noforceuid" },
+	{ Opt_forcegid, "forcegid" },
+	{ Opt_noforcegid, "noforcegid" },
+	{ Opt_noblocksend, "noblocksend" },
+	{ Opt_noautotune, "noautotune" },
+	{ Opt_nolease, "nolease" },
+	{ Opt_hard, "hard" },
+	{ Opt_soft, "soft" },
+	{ Opt_perm, "perm" },
+	{ Opt_noperm, "noperm" },
+	{ Opt_mapchars, "mapchars" }, /* SFU style */
+	{ Opt_nomapchars, "nomapchars" },
+	{ Opt_mapposix, "mapposix" }, /* SFM style */
+	{ Opt_nomapposix, "nomapposix" },
+	{ Opt_sfu, "sfu" },
+	{ Opt_nosfu, "nosfu" },
+	{ Opt_nodfs, "nodfs" },
+	{ Opt_posixpaths, "posixpaths" },
+	{ Opt_noposixpaths, "noposixpaths" },
+	{ Opt_nounix, "nounix" },
+	{ Opt_nounix, "nolinux" },
+	{ Opt_nounix, "noposix" },
+	{ Opt_unix, "unix" },
+	{ Opt_unix, "linux" },
+	{ Opt_unix, "posix" },
+	{ Opt_nocase, "nocase" },
+	{ Opt_nocase, "ignorecase" },
+	{ Opt_brl, "brl" },
+	{ Opt_nobrl, "nobrl" },
+	{ Opt_handlecache, "handlecache" },
+	{ Opt_nohandlecache, "nohandlecache" },
+	{ Opt_nobrl, "nolock" },
+	{ Opt_forcemandatorylock, "forcemandatorylock" },
+	{ Opt_forcemandatorylock, "forcemand" },
+	{ Opt_setuids, "setuids" },
+	{ Opt_nosetuids, "nosetuids" },
+	{ Opt_setuidfromacl, "idsfromsid" },
+	{ Opt_dynperm, "dynperm" },
+	{ Opt_nodynperm, "nodynperm" },
+	{ Opt_nohard, "nohard" },
+	{ Opt_nosoft, "nosoft" },
+	{ Opt_nointr, "nointr" },
+	{ Opt_intr, "intr" },
+	{ Opt_nostrictsync, "nostrictsync" },
+	{ Opt_strictsync, "strictsync" },
+	{ Opt_serverino, "serverino" },
+	{ Opt_noserverino, "noserverino" },
+	{ Opt_rwpidforward, "rwpidforward" },
+	{ Opt_cifsacl, "cifsacl" },
+	{ Opt_nocifsacl, "nocifsacl" },
+	{ Opt_acl, "acl" },
+	{ Opt_noacl, "noacl" },
+	{ Opt_locallease, "locallease" },
+	{ Opt_sign, "sign" },
+	{ Opt_seal, "seal" },
+	{ Opt_noac, "noac" },
+	{ Opt_fsc, "fsc" },
+	{ Opt_mfsymlinks, "mfsymlinks" },
+	{ Opt_multiuser, "multiuser" },
+	{ Opt_sloppy, "sloppy" },
+	{ Opt_nosharesock, "nosharesock" },
+	{ Opt_persistent, "persistenthandles"},
+	{ Opt_nopersistent, "nopersistenthandles"},
+	{ Opt_resilient, "resilienthandles"},
+	{ Opt_noresilient, "noresilienthandles"},
+	{ Opt_domainauto, "domainauto"},
+	{ Opt_rdma, "rdma"},
+
+	{ Opt_backupuid, "backupuid=%s" },
+	{ Opt_backupgid, "backupgid=%s" },
+	{ Opt_uid, "uid=%s" },
+	{ Opt_cruid, "cruid=%s" },
+	{ Opt_gid, "gid=%s" },
+	{ Opt_file_mode, "file_mode=%s" },
+	{ Opt_dirmode, "dirmode=%s" },
+	{ Opt_dirmode, "dir_mode=%s" },
+	{ Opt_port, "port=%s" },
+	{ Opt_rsize, "rsize=%s" },
+	{ Opt_wsize, "wsize=%s" },
+	{ Opt_actimeo, "actimeo=%s" },
+	{ Opt_echo_interval, "echo_interval=%s" },
+	{ Opt_max_credits, "max_credits=%s" },
+	{ Opt_snapshot, "snapshot=%s" },
+
+	{ Opt_blank_user, "user=" },
+	{ Opt_blank_user, "username=" },
+	{ Opt_user, "user=%s" },
+	{ Opt_user, "username=%s" },
+	{ Opt_blank_pass, "pass=" },
+	{ Opt_blank_pass, "password=" },
+	{ Opt_pass, "pass=%s" },
+	{ Opt_pass, "password=%s" },
+	{ Opt_blank_ip, "ip=" },
+	{ Opt_blank_ip, "addr=" },
+	{ Opt_ip, "ip=%s" },
+	{ Opt_ip, "addr=%s" },
+	{ Opt_ignore, "unc=%s" },
+	{ Opt_ignore, "target=%s" },
+	{ Opt_ignore, "path=%s" },
+	{ Opt_domain, "dom=%s" },
+	{ Opt_domain, "domain=%s" },
+	{ Opt_domain, "workgroup=%s" },
+	{ Opt_srcaddr, "srcaddr=%s" },
+	{ Opt_ignore, "prefixpath=%s" },
+	{ Opt_iocharset, "iocharset=%s" },
+	{ Opt_netbiosname, "netbiosname=%s" },
+	{ Opt_servern, "servern=%s" },
+	{ Opt_ver, "ver=%s" },
+	{ Opt_vers, "vers=%s" },
+	{ Opt_sec, "sec=%s" },
+	{ Opt_cache, "cache=%s" },
+
+	{ Opt_ignore, "cred" },
+	{ Opt_ignore, "credentials" },
+	{ Opt_ignore, "cred=%s" },
+	{ Opt_ignore, "credentials=%s" },
+	{ Opt_ignore, "guest" },
+	{ Opt_ignore, "rw" },
+	{ Opt_ignore, "ro" },
+	{ Opt_ignore, "suid" },
+	{ Opt_ignore, "nosuid" },
+	{ Opt_ignore, "exec" },
+	{ Opt_ignore, "noexec" },
+	{ Opt_ignore, "nodev" },
+	{ Opt_ignore, "noauto" },
+	{ Opt_ignore, "dev" },
+	{ Opt_ignore, "mand" },
+	{ Opt_ignore, "nomand" },
+	{ Opt_ignore, "_netdev" },
+
+	{ Opt_err, NULL }
+};
+
+enum {
+	Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
+	Opt_sec_ntlmsspi, Opt_sec_ntlmssp,
+	Opt_ntlm, Opt_sec_ntlmi, Opt_sec_ntlmv2,
+	Opt_sec_ntlmv2i, Opt_sec_lanman,
+	Opt_sec_none,
+
+	Opt_sec_err
+};
+
+static const match_table_t cifs_secflavor_tokens = {
+	{ Opt_sec_krb5, "krb5" },
+	{ Opt_sec_krb5i, "krb5i" },
+	{ Opt_sec_krb5p, "krb5p" },
+	{ Opt_sec_ntlmsspi, "ntlmsspi" },
+	{ Opt_sec_ntlmssp, "ntlmssp" },
+	{ Opt_ntlm, "ntlm" },
+	{ Opt_sec_ntlmi, "ntlmi" },
+	{ Opt_sec_ntlmv2, "nontlm" },
+	{ Opt_sec_ntlmv2, "ntlmv2" },
+	{ Opt_sec_ntlmv2i, "ntlmv2i" },
+	{ Opt_sec_lanman, "lanman" },
+	{ Opt_sec_none, "none" },
+
+	{ Opt_sec_err, NULL }
+};
+
+/* cache flavors */
+enum {
+	Opt_cache_loose,
+	Opt_cache_strict,
+	Opt_cache_none,
+	Opt_cache_err
+};
+
+static const match_table_t cifs_cacheflavor_tokens = {
+	{ Opt_cache_loose, "loose" },
+	{ Opt_cache_strict, "strict" },
+	{ Opt_cache_none, "none" },
+	{ Opt_cache_err, NULL }
+};
+
+static const match_table_t cifs_smb_version_tokens = {
+	{ Smb_1, SMB1_VERSION_STRING },
+	{ Smb_20, SMB20_VERSION_STRING},
+	{ Smb_21, SMB21_VERSION_STRING },
+	{ Smb_30, SMB30_VERSION_STRING },
+	{ Smb_302, SMB302_VERSION_STRING },
+	{ Smb_311, SMB311_VERSION_STRING },
+	{ Smb_311, ALT_SMB311_VERSION_STRING },
+	{ Smb_3any, SMB3ANY_VERSION_STRING },
+	{ Smb_default, SMBDEFAULT_VERSION_STRING },
+	{ Smb_version_err, NULL }
+};
+
+static int ip_connect(struct TCP_Server_Info *server);
+static int generic_ip_connect(struct TCP_Server_Info *server);
+static void tlink_rb_insert(struct rb_root *root, struct tcon_link *new_tlink);
+static void cifs_prune_tlinks(struct work_struct *work);
+static int cifs_setup_volume_info(struct smb_vol *volume_info, char *mount_data,
+					const char *devname, bool is_smb3);
+
+/*
+ * Resolve hostname and set ip addr in tcp ses. Useful for hostnames that may
+ * get their ip addresses changed at some point.
+ *
+ * This should be called with server->srv_mutex held.
+ */
+#ifdef CONFIG_CIFS_DFS_UPCALL
+static int reconn_set_ipaddr(struct TCP_Server_Info *server)
+{
+	int rc;
+	int len;
+	char *unc, *ipaddr = NULL;
+
+	if (!server->hostname)
+		return -EINVAL;
+
+	len = strlen(server->hostname) + 3;
+
+	unc = kmalloc(len, GFP_KERNEL);
+	if (!unc) {
+		cifs_dbg(FYI, "%s: failed to create UNC path\n", __func__);
+		return -ENOMEM;
+	}
+	snprintf(unc, len, "\\\\%s", server->hostname);
+
+	rc = dns_resolve_server_name_to_ip(unc, &ipaddr);
+	kfree(unc);
+
+	if (rc < 0) {
+		cifs_dbg(FYI, "%s: failed to resolve server part of %s to IP: %d\n",
+			 __func__, server->hostname, rc);
+		return rc;
+	}
+
+	spin_lock(&cifs_tcp_ses_lock);
+	rc = cifs_convert_address((struct sockaddr *)&server->dstaddr, ipaddr,
+				  strlen(ipaddr));
+	spin_unlock(&cifs_tcp_ses_lock);
+	kfree(ipaddr);
+
+	return !rc ? -1 : 0;
+}
+#else
+static inline int reconn_set_ipaddr(struct TCP_Server_Info *server)
+{
+	return 0;
+}
+#endif
+
+/*
+ * cifs tcp session reconnection
+ *
+ * mark tcp session as reconnecting so temporarily locked
+ * mark all smb sessions as reconnecting for tcp session
+ * reconnect tcp session
+ * wake up waiters on reconnection? - (not needed currently)
+ */
+int
+cifs_reconnect(struct TCP_Server_Info *server)
+{
+	int rc = 0;
+	struct list_head *tmp, *tmp2;
+	struct cifs_ses *ses;
+	struct cifs_tcon *tcon;
+	struct mid_q_entry *mid_entry;
+	struct list_head retry_list;
+
+	spin_lock(&GlobalMid_Lock);
+	if (server->tcpStatus == CifsExiting) {
+		/* the demux thread will exit normally
+		next time through the loop */
+		spin_unlock(&GlobalMid_Lock);
+		return rc;
+	} else
+		server->tcpStatus = CifsNeedReconnect;
+	spin_unlock(&GlobalMid_Lock);
+	server->maxBuf = 0;
+	server->max_read = 0;
+
+	cifs_dbg(FYI, "Reconnecting tcp session\n");
+	trace_smb3_reconnect(server->CurrentMid, server->hostname);
+
+	/* before reconnecting the tcp session, mark the smb session (uid)
+		and the tid bad so they are not used until reconnected */
+	cifs_dbg(FYI, "%s: marking sessions and tcons for reconnect\n",
+		 __func__);
+	spin_lock(&cifs_tcp_ses_lock);
+	list_for_each(tmp, &server->smb_ses_list) {
+		ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
+		ses->need_reconnect = true;
+		list_for_each(tmp2, &ses->tcon_list) {
+			tcon = list_entry(tmp2, struct cifs_tcon, tcon_list);
+			tcon->need_reconnect = true;
+		}
+		if (ses->tcon_ipc)
+			ses->tcon_ipc->need_reconnect = true;
+	}
+	spin_unlock(&cifs_tcp_ses_lock);
+
+	/* do not want to be sending data on a socket we are freeing */
+	cifs_dbg(FYI, "%s: tearing down socket\n", __func__);
+	mutex_lock(&server->srv_mutex);
+	if (server->ssocket) {
+		cifs_dbg(FYI, "State: 0x%x Flags: 0x%lx\n",
+			 server->ssocket->state, server->ssocket->flags);
+		kernel_sock_shutdown(server->ssocket, SHUT_WR);
+		cifs_dbg(FYI, "Post shutdown state: 0x%x Flags: 0x%lx\n",
+			 server->ssocket->state, server->ssocket->flags);
+		sock_release(server->ssocket);
+		server->ssocket = NULL;
+	}
+	server->sequence_number = 0;
+	server->session_estab = false;
+	kfree(server->session_key.response);
+	server->session_key.response = NULL;
+	server->session_key.len = 0;
+	server->lstrp = jiffies;
+
+	/* mark submitted MIDs for retry and issue callback */
+	INIT_LIST_HEAD(&retry_list);
+	cifs_dbg(FYI, "%s: moving mids to private list\n", __func__);
+	spin_lock(&GlobalMid_Lock);
+	list_for_each_safe(tmp, tmp2, &server->pending_mid_q) {
+		mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
+		if (mid_entry->mid_state == MID_REQUEST_SUBMITTED)
+			mid_entry->mid_state = MID_RETRY_NEEDED;
+		list_move(&mid_entry->qhead, &retry_list);
+	}
+	spin_unlock(&GlobalMid_Lock);
+	mutex_unlock(&server->srv_mutex);
+
+	cifs_dbg(FYI, "%s: issuing mid callbacks\n", __func__);
+	list_for_each_safe(tmp, tmp2, &retry_list) {
+		mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
+		list_del_init(&mid_entry->qhead);
+		mid_entry->callback(mid_entry);
+	}
+
+	do {
+		try_to_freeze();
+
+		/* we should try only the port we connected to before */
+		mutex_lock(&server->srv_mutex);
+		if (cifs_rdma_enabled(server))
+			rc = smbd_reconnect(server);
+		else
+			rc = generic_ip_connect(server);
+		if (rc) {
+			cifs_dbg(FYI, "reconnect error %d\n", rc);
+			rc = reconn_set_ipaddr(server);
+			if (rc) {
+				cifs_dbg(FYI, "%s: failed to resolve hostname: %d\n",
+					 __func__, rc);
+			}
+			mutex_unlock(&server->srv_mutex);
+			msleep(3000);
+		} else {
+			atomic_inc(&tcpSesReconnectCount);
+			spin_lock(&GlobalMid_Lock);
+			if (server->tcpStatus != CifsExiting)
+				server->tcpStatus = CifsNeedNegotiate;
+			spin_unlock(&GlobalMid_Lock);
+			mutex_unlock(&server->srv_mutex);
+		}
+	} while (server->tcpStatus == CifsNeedReconnect);
+
+	if (server->tcpStatus == CifsNeedNegotiate)
+		mod_delayed_work(cifsiod_wq, &server->echo, 0);
+
+	return rc;
+}
+
+static void
+cifs_echo_request(struct work_struct *work)
+{
+	int rc;
+	struct TCP_Server_Info *server = container_of(work,
+					struct TCP_Server_Info, echo.work);
+	unsigned long echo_interval;
+
+	/*
+	 * If we need to renegotiate, set echo interval to zero to
+	 * immediately call echo service where we can renegotiate.
+	 */
+	if (server->tcpStatus == CifsNeedNegotiate)
+		echo_interval = 0;
+	else
+		echo_interval = server->echo_interval;
+
+	/*
+	 * We cannot send an echo if it is disabled.
+	 * Also, no need to ping if we got a response recently.
+	 */
+
+	if (server->tcpStatus == CifsNeedReconnect ||
+	    server->tcpStatus == CifsExiting ||
+	    server->tcpStatus == CifsNew ||
+	    (server->ops->can_echo && !server->ops->can_echo(server)) ||
+	    time_before(jiffies, server->lstrp + echo_interval - HZ))
+		goto requeue_echo;
+
+	rc = server->ops->echo ? server->ops->echo(server) : -ENOSYS;
+	if (rc)
+		cifs_dbg(FYI, "Unable to send echo request to server: %s\n",
+			 server->hostname);
+
+requeue_echo:
+	queue_delayed_work(cifsiod_wq, &server->echo, server->echo_interval);
+}
+
+static bool
+allocate_buffers(struct TCP_Server_Info *server)
+{
+	if (!server->bigbuf) {
+		server->bigbuf = (char *)cifs_buf_get();
+		if (!server->bigbuf) {
+			cifs_dbg(VFS, "No memory for large SMB response\n");
+			msleep(3000);
+			/* retry will check if exiting */
+			return false;
+		}
+	} else if (server->large_buf) {
+		/* we are reusing a dirty large buf, clear its start */
+		memset(server->bigbuf, 0, HEADER_SIZE(server));
+	}
+
+	if (!server->smallbuf) {
+		server->smallbuf = (char *)cifs_small_buf_get();
+		if (!server->smallbuf) {
+			cifs_dbg(VFS, "No memory for SMB response\n");
+			msleep(1000);
+			/* retry will check if exiting */
+			return false;
+		}
+		/* beginning of smb buffer is cleared in our buf_get */
+	} else {
+		/* if existing small buf clear beginning */
+		memset(server->smallbuf, 0, HEADER_SIZE(server));
+	}
+
+	return true;
+}
+
+static bool
+server_unresponsive(struct TCP_Server_Info *server)
+{
+	/*
+	 * We need to wait 3 echo intervals to make sure we handle such
+	 * situations right:
+	 * 1s  client sends a normal SMB request
+	 * 3s  client gets a response
+	 * 30s echo workqueue job pops, and decides we got a response recently
+	 *     and don't need to send another
+	 * ...
+	 * 65s kernel_recvmsg times out, and we see that we haven't gotten
+	 *     a response in >60s.
+	 */
+	if ((server->tcpStatus == CifsGood ||
+	    server->tcpStatus == CifsNeedNegotiate) &&
+	    time_after(jiffies, server->lstrp + 3 * server->echo_interval)) {
+		cifs_dbg(VFS, "Server %s has not responded in %lu seconds. Reconnecting...\n",
+			 server->hostname, (3 * server->echo_interval) / HZ);
+		cifs_reconnect(server);
+		wake_up(&server->response_q);
+		return true;
+	}
+
+	return false;
+}
+
+static inline bool
+zero_credits(struct TCP_Server_Info *server)
+{
+	int val;
+
+	spin_lock(&server->req_lock);
+	val = server->credits + server->echo_credits + server->oplock_credits;
+	if (server->in_flight == 0 && val == 0) {
+		spin_unlock(&server->req_lock);
+		return true;
+	}
+	spin_unlock(&server->req_lock);
+	return false;
+}
+
+static int
+cifs_readv_from_socket(struct TCP_Server_Info *server, struct msghdr *smb_msg)
+{
+	int length = 0;
+	int total_read;
+
+	smb_msg->msg_control = NULL;
+	smb_msg->msg_controllen = 0;
+
+	for (total_read = 0; msg_data_left(smb_msg); total_read += length) {
+		try_to_freeze();
+
+		/* reconnect if no credits and no requests in flight */
+		if (zero_credits(server)) {
+			cifs_reconnect(server);
+			return -ECONNABORTED;
+		}
+
+		if (server_unresponsive(server))
+			return -ECONNABORTED;
+		if (cifs_rdma_enabled(server) && server->smbd_conn)
+			length = smbd_recv(server->smbd_conn, smb_msg);
+		else
+			length = sock_recvmsg(server->ssocket, smb_msg, 0);
+
+		if (server->tcpStatus == CifsExiting)
+			return -ESHUTDOWN;
+
+		if (server->tcpStatus == CifsNeedReconnect) {
+			cifs_reconnect(server);
+			return -ECONNABORTED;
+		}
+
+		if (length == -ERESTARTSYS ||
+		    length == -EAGAIN ||
+		    length == -EINTR) {
+			/*
+			 * Minimum sleep to prevent looping, allowing socket
+			 * to clear and app threads to set tcpStatus
+			 * CifsNeedReconnect if server hung.
+			 */
+			usleep_range(1000, 2000);
+			length = 0;
+			continue;
+		}
+
+		if (length <= 0) {
+			cifs_dbg(FYI, "Received no data or error: %d\n", length);
+			cifs_reconnect(server);
+			return -ECONNABORTED;
+		}
+	}
+	return total_read;
+}
+
+int
+cifs_read_from_socket(struct TCP_Server_Info *server, char *buf,
+		      unsigned int to_read)
+{
+	struct msghdr smb_msg;
+	struct kvec iov = {.iov_base = buf, .iov_len = to_read};
+	iov_iter_kvec(&smb_msg.msg_iter, READ | ITER_KVEC, &iov, 1, to_read);
+
+	return cifs_readv_from_socket(server, &smb_msg);
+}
+
+int
+cifs_read_page_from_socket(struct TCP_Server_Info *server, struct page *page,
+	unsigned int page_offset, unsigned int to_read)
+{
+	struct msghdr smb_msg;
+	struct bio_vec bv = {
+		.bv_page = page, .bv_len = to_read, .bv_offset = page_offset};
+	iov_iter_bvec(&smb_msg.msg_iter, READ | ITER_BVEC, &bv, 1, to_read);
+	return cifs_readv_from_socket(server, &smb_msg);
+}
+
+static bool
+is_smb_response(struct TCP_Server_Info *server, unsigned char type)
+{
+	/*
+	 * The first byte big endian of the length field,
+	 * is actually not part of the length but the type
+	 * with the most common, zero, as regular data.
+	 */
+	switch (type) {
+	case RFC1002_SESSION_MESSAGE:
+		/* Regular SMB response */
+		return true;
+	case RFC1002_SESSION_KEEP_ALIVE:
+		cifs_dbg(FYI, "RFC 1002 session keep alive\n");
+		break;
+	case RFC1002_POSITIVE_SESSION_RESPONSE:
+		cifs_dbg(FYI, "RFC 1002 positive session response\n");
+		break;
+	case RFC1002_NEGATIVE_SESSION_RESPONSE:
+		/*
+		 * We get this from Windows 98 instead of an error on
+		 * SMB negprot response.
+		 */
+		cifs_dbg(FYI, "RFC 1002 negative session response\n");
+		/* give server a second to clean up */
+		msleep(1000);
+		/*
+		 * Always try 445 first on reconnect since we get NACK
+		 * on some if we ever connected to port 139 (the NACK
+		 * is since we do not begin with RFC1001 session
+		 * initialize frame).
+		 */
+		cifs_set_port((struct sockaddr *)&server->dstaddr, CIFS_PORT);
+		cifs_reconnect(server);
+		wake_up(&server->response_q);
+		break;
+	default:
+		cifs_dbg(VFS, "RFC 1002 unknown response type 0x%x\n", type);
+		cifs_reconnect(server);
+	}
+
+	return false;
+}
+
+void
+dequeue_mid(struct mid_q_entry *mid, bool malformed)
+{
+#ifdef CONFIG_CIFS_STATS2
+	mid->when_received = jiffies;
+#endif
+	spin_lock(&GlobalMid_Lock);
+	if (!malformed)
+		mid->mid_state = MID_RESPONSE_RECEIVED;
+	else
+		mid->mid_state = MID_RESPONSE_MALFORMED;
+	/*
+	 * Trying to handle/dequeue a mid after the send_recv()
+	 * function has finished processing it is a bug.
+	 */
+	if (mid->mid_flags & MID_DELETED)
+		printk_once(KERN_WARNING
+			    "trying to dequeue a deleted mid\n");
+	else
+		list_del_init(&mid->qhead);
+	spin_unlock(&GlobalMid_Lock);
+}
+
+static void
+handle_mid(struct mid_q_entry *mid, struct TCP_Server_Info *server,
+	   char *buf, int malformed)
+{
+	if (server->ops->check_trans2 &&
+	    server->ops->check_trans2(mid, server, buf, malformed))
+		return;
+	mid->resp_buf = buf;
+	mid->large_buf = server->large_buf;
+	/* Was previous buf put in mpx struct for multi-rsp? */
+	if (!mid->multiRsp) {
+		/* smb buffer will be freed by user thread */
+		if (server->large_buf)
+			server->bigbuf = NULL;
+		else
+			server->smallbuf = NULL;
+	}
+	dequeue_mid(mid, malformed);
+}
+
+static void clean_demultiplex_info(struct TCP_Server_Info *server)
+{
+	int length;
+
+	/* take it off the list, if it's not already */
+	spin_lock(&cifs_tcp_ses_lock);
+	list_del_init(&server->tcp_ses_list);
+	spin_unlock(&cifs_tcp_ses_lock);
+
+	cancel_delayed_work_sync(&server->echo);
+
+	spin_lock(&GlobalMid_Lock);
+	server->tcpStatus = CifsExiting;
+	spin_unlock(&GlobalMid_Lock);
+	wake_up_all(&server->response_q);
+
+	/* check if we have blocked requests that need to free */
+	spin_lock(&server->req_lock);
+	if (server->credits <= 0)
+		server->credits = 1;
+	spin_unlock(&server->req_lock);
+	/*
+	 * Although there should not be any requests blocked on this queue it
+	 * can not hurt to be paranoid and try to wake up requests that may
+	 * haven been blocked when more than 50 at time were on the wire to the
+	 * same server - they now will see the session is in exit state and get
+	 * out of SendReceive.
+	 */
+	wake_up_all(&server->request_q);
+	/* give those requests time to exit */
+	msleep(125);
+	if (cifs_rdma_enabled(server) && server->smbd_conn) {
+		smbd_destroy(server->smbd_conn);
+		server->smbd_conn = NULL;
+	}
+	if (server->ssocket) {
+		sock_release(server->ssocket);
+		server->ssocket = NULL;
+	}
+
+	if (!list_empty(&server->pending_mid_q)) {
+		struct list_head dispose_list;
+		struct mid_q_entry *mid_entry;
+		struct list_head *tmp, *tmp2;
+
+		INIT_LIST_HEAD(&dispose_list);
+		spin_lock(&GlobalMid_Lock);
+		list_for_each_safe(tmp, tmp2, &server->pending_mid_q) {
+			mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
+			cifs_dbg(FYI, "Clearing mid 0x%llx\n", mid_entry->mid);
+			mid_entry->mid_state = MID_SHUTDOWN;
+			list_move(&mid_entry->qhead, &dispose_list);
+		}
+		spin_unlock(&GlobalMid_Lock);
+
+		/* now walk dispose list and issue callbacks */
+		list_for_each_safe(tmp, tmp2, &dispose_list) {
+			mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
+			cifs_dbg(FYI, "Callback mid 0x%llx\n", mid_entry->mid);
+			list_del_init(&mid_entry->qhead);
+			mid_entry->callback(mid_entry);
+		}
+		/* 1/8th of sec is more than enough time for them to exit */
+		msleep(125);
+	}
+
+	if (!list_empty(&server->pending_mid_q)) {
+		/*
+		 * mpx threads have not exited yet give them at least the smb
+		 * send timeout time for long ops.
+		 *
+		 * Due to delays on oplock break requests, we need to wait at
+		 * least 45 seconds before giving up on a request getting a
+		 * response and going ahead and killing cifsd.
+		 */
+		cifs_dbg(FYI, "Wait for exit from demultiplex thread\n");
+		msleep(46000);
+		/*
+		 * If threads still have not exited they are probably never
+		 * coming home not much else we can do but free the memory.
+		 */
+	}
+
+	kfree(server->hostname);
+	kfree(server);
+
+	length = atomic_dec_return(&tcpSesAllocCount);
+	if (length > 0)
+		mempool_resize(cifs_req_poolp, length + cifs_min_rcv);
+}
+
+static int
+standard_receive3(struct TCP_Server_Info *server, struct mid_q_entry *mid)
+{
+	int length;
+	char *buf = server->smallbuf;
+	unsigned int pdu_length = server->pdu_size;
+
+	/* make sure this will fit in a large buffer */
+	if (pdu_length > CIFSMaxBufSize + MAX_HEADER_SIZE(server) -
+		server->vals->header_preamble_size) {
+		cifs_dbg(VFS, "SMB response too long (%u bytes)\n", pdu_length);
+		cifs_reconnect(server);
+		wake_up(&server->response_q);
+		return -ECONNABORTED;
+	}
+
+	/* switch to large buffer if too big for a small one */
+	if (pdu_length > MAX_CIFS_SMALL_BUFFER_SIZE - 4) {
+		server->large_buf = true;
+		memcpy(server->bigbuf, buf, server->total_read);
+		buf = server->bigbuf;
+	}
+
+	/* now read the rest */
+	length = cifs_read_from_socket(server, buf + HEADER_SIZE(server) - 1,
+				       pdu_length - HEADER_SIZE(server) + 1
+				       + server->vals->header_preamble_size);
+
+	if (length < 0)
+		return length;
+	server->total_read += length;
+
+	dump_smb(buf, server->total_read);
+
+	return cifs_handle_standard(server, mid);
+}
+
+int
+cifs_handle_standard(struct TCP_Server_Info *server, struct mid_q_entry *mid)
+{
+	char *buf = server->large_buf ? server->bigbuf : server->smallbuf;
+	int length;
+
+	/*
+	 * We know that we received enough to get to the MID as we
+	 * checked the pdu_length earlier. Now check to see
+	 * if the rest of the header is OK. We borrow the length
+	 * var for the rest of the loop to avoid a new stack var.
+	 *
+	 * 48 bytes is enough to display the header and a little bit
+	 * into the payload for debugging purposes.
+	 */
+	length = server->ops->check_message(buf, server->total_read, server);
+	if (length != 0)
+		cifs_dump_mem("Bad SMB: ", buf,
+			min_t(unsigned int, server->total_read, 48));
+
+	if (server->ops->is_session_expired &&
+	    server->ops->is_session_expired(buf)) {
+		cifs_reconnect(server);
+		wake_up(&server->response_q);
+		return -1;
+	}
+
+	if (server->ops->is_status_pending &&
+	    server->ops->is_status_pending(buf, server, length))
+		return -1;
+
+	if (!mid)
+		return length;
+
+	handle_mid(mid, server, buf, length);
+	return 0;
+}
+
+static void
+smb2_add_credits_from_hdr(char *buffer, struct TCP_Server_Info *server)
+{
+	struct smb2_sync_hdr *shdr = (struct smb2_sync_hdr *)buffer;
+
+	/*
+	 * SMB1 does not use credits.
+	 */
+	if (server->vals->header_preamble_size)
+		return;
+
+	if (shdr->CreditRequest) {
+		spin_lock(&server->req_lock);
+		server->credits += le16_to_cpu(shdr->CreditRequest);
+		spin_unlock(&server->req_lock);
+		wake_up(&server->request_q);
+	}
+}
+
+
+static int
+cifs_demultiplex_thread(void *p)
+{
+	int i, num_mids, length;
+	struct TCP_Server_Info *server = p;
+	unsigned int pdu_length;
+	unsigned int next_offset;
+	char *buf = NULL;
+	struct task_struct *task_to_wake = NULL;
+	struct mid_q_entry *mids[MAX_COMPOUND];
+	char *bufs[MAX_COMPOUND];
+
+	current->flags |= PF_MEMALLOC;
+	cifs_dbg(FYI, "Demultiplex PID: %d\n", task_pid_nr(current));
+
+	length = atomic_inc_return(&tcpSesAllocCount);
+	if (length > 1)
+		mempool_resize(cifs_req_poolp, length + cifs_min_rcv);
+
+	set_freezable();
+	allow_kernel_signal(SIGKILL);
+	while (server->tcpStatus != CifsExiting) {
+		if (try_to_freeze())
+			continue;
+
+		if (!allocate_buffers(server))
+			continue;
+
+		server->large_buf = false;
+		buf = server->smallbuf;
+		pdu_length = 4; /* enough to get RFC1001 header */
+
+		length = cifs_read_from_socket(server, buf, pdu_length);
+		if (length < 0)
+			continue;
+
+		if (server->vals->header_preamble_size == 0)
+			server->total_read = 0;
+		else
+			server->total_read = length;
+
+		/*
+		 * The right amount was read from socket - 4 bytes,
+		 * so we can now interpret the length field.
+		 */
+		pdu_length = get_rfc1002_length(buf);
+
+		cifs_dbg(FYI, "RFC1002 header 0x%x\n", pdu_length);
+		if (!is_smb_response(server, buf[0]))
+			continue;
+next_pdu:
+		server->pdu_size = pdu_length;
+
+		/* make sure we have enough to get to the MID */
+		if (server->pdu_size < HEADER_SIZE(server) - 1 -
+		    server->vals->header_preamble_size) {
+			cifs_dbg(VFS, "SMB response too short (%u bytes)\n",
+				 server->pdu_size);
+			cifs_reconnect(server);
+			wake_up(&server->response_q);
+			continue;
+		}
+
+		/* read down to the MID */
+		length = cifs_read_from_socket(server,
+			     buf + server->vals->header_preamble_size,
+			     HEADER_SIZE(server) - 1
+			     - server->vals->header_preamble_size);
+		if (length < 0)
+			continue;
+		server->total_read += length;
+
+		if (server->ops->next_header) {
+			next_offset = server->ops->next_header(buf);
+			if (next_offset)
+				server->pdu_size = next_offset;
+		}
+
+		memset(mids, 0, sizeof(mids));
+		memset(bufs, 0, sizeof(bufs));
+		num_mids = 0;
+
+		if (server->ops->is_transform_hdr &&
+		    server->ops->receive_transform &&
+		    server->ops->is_transform_hdr(buf)) {
+			length = server->ops->receive_transform(server,
+								mids,
+								bufs,
+								&num_mids);
+		} else {
+			mids[0] = server->ops->find_mid(server, buf);
+			bufs[0] = buf;
+			num_mids = 1;
+
+			if (!mids[0] || !mids[0]->receive)
+				length = standard_receive3(server, mids[0]);
+			else
+				length = mids[0]->receive(server, mids[0]);
+		}
+
+		if (length < 0) {
+			for (i = 0; i < num_mids; i++)
+				if (mids[i])
+					cifs_mid_q_entry_release(mids[i]);
+			continue;
+		}
+
+		if (server->large_buf)
+			buf = server->bigbuf;
+
+
+		server->lstrp = jiffies;
+
+		for (i = 0; i < num_mids; i++) {
+			if (mids[i] != NULL) {
+				mids[i]->resp_buf_size = server->pdu_size;
+				if ((mids[i]->mid_flags & MID_WAIT_CANCELLED) &&
+				    mids[i]->mid_state == MID_RESPONSE_RECEIVED &&
+				    server->ops->handle_cancelled_mid)
+					server->ops->handle_cancelled_mid(
+							mids[i]->resp_buf,
+							server);
+
+				if (!mids[i]->multiRsp || mids[i]->multiEnd)
+					mids[i]->callback(mids[i]);
+
+				cifs_mid_q_entry_release(mids[i]);
+			} else if (server->ops->is_oplock_break &&
+				   server->ops->is_oplock_break(bufs[i],
+								server)) {
+				smb2_add_credits_from_hdr(bufs[i], server);
+				cifs_dbg(FYI, "Received oplock break\n");
+			} else {
+				cifs_dbg(VFS, "No task to wake, unknown frame "
+					 "received! NumMids %d\n",
+					 atomic_read(&midCount));
+				cifs_dump_mem("Received Data is: ", bufs[i],
+					      HEADER_SIZE(server));
+#ifdef CONFIG_CIFS_DEBUG2
+				if (server->ops->dump_detail)
+					server->ops->dump_detail(bufs[i],
+								 server);
+				smb2_add_credits_from_hdr(bufs[i], server);
+				cifs_dump_mids(server);
+#endif /* CIFS_DEBUG2 */
+			}
+		}
+
+		if (pdu_length > server->pdu_size) {
+			if (!allocate_buffers(server))
+				continue;
+			pdu_length -= server->pdu_size;
+			server->total_read = 0;
+			server->large_buf = false;
+			buf = server->smallbuf;
+			goto next_pdu;
+		}
+	} /* end while !EXITING */
+
+	/* buffer usually freed in free_mid - need to free it here on exit */
+	cifs_buf_release(server->bigbuf);
+	if (server->smallbuf) /* no sense logging a debug message if NULL */
+		cifs_small_buf_release(server->smallbuf);
+
+	task_to_wake = xchg(&server->tsk, NULL);
+	clean_demultiplex_info(server);
+
+	/* if server->tsk was NULL then wait for a signal before exiting */
+	if (!task_to_wake) {
+		set_current_state(TASK_INTERRUPTIBLE);
+		while (!signal_pending(current)) {
+			schedule();
+			set_current_state(TASK_INTERRUPTIBLE);
+		}
+		set_current_state(TASK_RUNNING);
+	}
+
+	module_put_and_exit(0);
+}
+
+/* extract the host portion of the UNC string */
+static char *
+extract_hostname(const char *unc)
+{
+	const char *src;
+	char *dst, *delim;
+	unsigned int len;
+
+	/* skip double chars at beginning of string */
+	/* BB: check validity of these bytes? */
+	src = unc + 2;
+
+	/* delimiter between hostname and sharename is always '\\' now */
+	delim = strchr(src, '\\');
+	if (!delim)
+		return ERR_PTR(-EINVAL);
+
+	len = delim - src;
+	dst = kmalloc((len + 1), GFP_KERNEL);
+	if (dst == NULL)
+		return ERR_PTR(-ENOMEM);
+
+	memcpy(dst, src, len);
+	dst[len] = '\0';
+
+	return dst;
+}
+
+static int get_option_ul(substring_t args[], unsigned long *option)
+{
+	int rc;
+	char *string;
+
+	string = match_strdup(args);
+	if (string == NULL)
+		return -ENOMEM;
+	rc = kstrtoul(string, 0, option);
+	kfree(string);
+
+	return rc;
+}
+
+static int get_option_uid(substring_t args[], kuid_t *result)
+{
+	unsigned long value;
+	kuid_t uid;
+	int rc;
+
+	rc = get_option_ul(args, &value);
+	if (rc)
+		return rc;
+
+	uid = make_kuid(current_user_ns(), value);
+	if (!uid_valid(uid))
+		return -EINVAL;
+
+	*result = uid;
+	return 0;
+}
+
+static int get_option_gid(substring_t args[], kgid_t *result)
+{
+	unsigned long value;
+	kgid_t gid;
+	int rc;
+
+	rc = get_option_ul(args, &value);
+	if (rc)
+		return rc;
+
+	gid = make_kgid(current_user_ns(), value);
+	if (!gid_valid(gid))
+		return -EINVAL;
+
+	*result = gid;
+	return 0;
+}
+
+static int cifs_parse_security_flavors(char *value,
+				       struct smb_vol *vol)
+{
+
+	substring_t args[MAX_OPT_ARGS];
+
+	/*
+	 * With mount options, the last one should win. Reset any existing
+	 * settings back to default.
+	 */
+	vol->sectype = Unspecified;
+	vol->sign = false;
+
+	switch (match_token(value, cifs_secflavor_tokens, args)) {
+	case Opt_sec_krb5p:
+		cifs_dbg(VFS, "sec=krb5p is not supported!\n");
+		return 1;
+	case Opt_sec_krb5i:
+		vol->sign = true;
+		/* Fallthrough */
+	case Opt_sec_krb5:
+		vol->sectype = Kerberos;
+		break;
+	case Opt_sec_ntlmsspi:
+		vol->sign = true;
+		/* Fallthrough */
+	case Opt_sec_ntlmssp:
+		vol->sectype = RawNTLMSSP;
+		break;
+	case Opt_sec_ntlmi:
+		vol->sign = true;
+		/* Fallthrough */
+	case Opt_ntlm:
+		vol->sectype = NTLM;
+		break;
+	case Opt_sec_ntlmv2i:
+		vol->sign = true;
+		/* Fallthrough */
+	case Opt_sec_ntlmv2:
+		vol->sectype = NTLMv2;
+		break;
+#ifdef CONFIG_CIFS_WEAK_PW_HASH
+	case Opt_sec_lanman:
+		vol->sectype = LANMAN;
+		break;
+#endif
+	case Opt_sec_none:
+		vol->nullauth = 1;
+		break;
+	default:
+		cifs_dbg(VFS, "bad security option: %s\n", value);
+		return 1;
+	}
+
+	return 0;
+}
+
+static int
+cifs_parse_cache_flavor(char *value, struct smb_vol *vol)
+{
+	substring_t args[MAX_OPT_ARGS];
+
+	switch (match_token(value, cifs_cacheflavor_tokens, args)) {
+	case Opt_cache_loose:
+		vol->direct_io = false;
+		vol->strict_io = false;
+		break;
+	case Opt_cache_strict:
+		vol->direct_io = false;
+		vol->strict_io = true;
+		break;
+	case Opt_cache_none:
+		vol->direct_io = true;
+		vol->strict_io = false;
+		break;
+	default:
+		cifs_dbg(VFS, "bad cache= option: %s\n", value);
+		return 1;
+	}
+	return 0;
+}
+
+static int
+cifs_parse_smb_version(char *value, struct smb_vol *vol, bool is_smb3)
+{
+	substring_t args[MAX_OPT_ARGS];
+
+	switch (match_token(value, cifs_smb_version_tokens, args)) {
+#ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
+	case Smb_1:
+		if (disable_legacy_dialects) {
+			cifs_dbg(VFS, "mount with legacy dialect disabled\n");
+			return 1;
+		}
+		if (is_smb3) {
+			cifs_dbg(VFS, "vers=1.0 (cifs) not permitted when mounting with smb3\n");
+			return 1;
+		}
+		vol->ops = &smb1_operations;
+		vol->vals = &smb1_values;
+		break;
+	case Smb_20:
+		if (disable_legacy_dialects) {
+			cifs_dbg(VFS, "mount with legacy dialect disabled\n");
+			return 1;
+		}
+		if (is_smb3) {
+			cifs_dbg(VFS, "vers=2.0 not permitted when mounting with smb3\n");
+			return 1;
+		}
+		vol->ops = &smb20_operations;
+		vol->vals = &smb20_values;
+		break;
+#else
+	case Smb_1:
+		cifs_dbg(VFS, "vers=1.0 (cifs) mount not permitted when legacy dialects disabled\n");
+		return 1;
+	case Smb_20:
+		cifs_dbg(VFS, "vers=2.0 mount not permitted when legacy dialects disabled\n");
+		return 1;
+#endif /* CIFS_ALLOW_INSECURE_LEGACY */
+	case Smb_21:
+		vol->ops = &smb21_operations;
+		vol->vals = &smb21_values;
+		break;
+	case Smb_30:
+		vol->ops = &smb30_operations;
+		vol->vals = &smb30_values;
+		break;
+	case Smb_302:
+		vol->ops = &smb30_operations; /* currently identical with 3.0 */
+		vol->vals = &smb302_values;
+		break;
+	case Smb_311:
+		vol->ops = &smb311_operations;
+		vol->vals = &smb311_values;
+		break;
+	case Smb_3any:
+		vol->ops = &smb30_operations; /* currently identical with 3.0 */
+		vol->vals = &smb3any_values;
+		break;
+	case Smb_default:
+		vol->ops = &smb30_operations; /* currently identical with 3.0 */
+		vol->vals = &smbdefault_values;
+		break;
+	default:
+		cifs_dbg(VFS, "Unknown vers= option specified: %s\n", value);
+		return 1;
+	}
+	return 0;
+}
+
+/*
+ * Parse a devname into substrings and populate the vol->UNC and vol->prepath
+ * fields with the result. Returns 0 on success and an error otherwise.
+ */
+static int
+cifs_parse_devname(const char *devname, struct smb_vol *vol)
+{
+	char *pos;
+	const char *delims = "/\\";
+	size_t len;
+
+	if (unlikely(!devname || !*devname)) {
+		cifs_dbg(VFS, "Device name not specified.\n");
+		return -EINVAL;
+	}
+
+	/* make sure we have a valid UNC double delimiter prefix */
+	len = strspn(devname, delims);
+	if (len != 2)
+		return -EINVAL;
+
+	/* find delimiter between host and sharename */
+	pos = strpbrk(devname + 2, delims);
+	if (!pos)
+		return -EINVAL;
+
+	/* skip past delimiter */
+	++pos;
+
+	/* now go until next delimiter or end of string */
+	len = strcspn(pos, delims);
+
+	/* move "pos" up to delimiter or NULL */
+	pos += len;
+	vol->UNC = kstrndup(devname, pos - devname, GFP_KERNEL);
+	if (!vol->UNC)
+		return -ENOMEM;
+
+	convert_delimiter(vol->UNC, '\\');
+
+	/* skip any delimiter */
+	if (*pos == '/' || *pos == '\\')
+		pos++;
+
+	/* If pos is NULL then no prepath */
+	if (!*pos)
+		return 0;
+
+	vol->prepath = kstrdup(pos, GFP_KERNEL);
+	if (!vol->prepath)
+		return -ENOMEM;
+
+	return 0;
+}
+
+static int
+cifs_parse_mount_options(const char *mountdata, const char *devname,
+			 struct smb_vol *vol, bool is_smb3)
+{
+	char *data, *end;
+	char *mountdata_copy = NULL, *options;
+	unsigned int  temp_len, i, j;
+	char separator[2];
+	short int override_uid = -1;
+	short int override_gid = -1;
+	bool uid_specified = false;
+	bool gid_specified = false;
+	bool sloppy = false;
+	char *invalid = NULL;
+	char *nodename = utsname()->nodename;
+	char *string = NULL;
+	char *tmp_end, *value;
+	char delim;
+	bool got_ip = false;
+	bool got_version = false;
+	unsigned short port = 0;
+	struct sockaddr *dstaddr = (struct sockaddr *)&vol->dstaddr;
+
+	separator[0] = ',';
+	separator[1] = 0;
+	delim = separator[0];
+
+	/* ensure we always start with zeroed-out smb_vol */
+	memset(vol, 0, sizeof(*vol));
+
+	/*
+	 * does not have to be perfect mapping since field is
+	 * informational, only used for servers that do not support
+	 * port 445 and it can be overridden at mount time
+	 */
+	memset(vol->source_rfc1001_name, 0x20, RFC1001_NAME_LEN);
+	for (i = 0; i < strnlen(nodename, RFC1001_NAME_LEN); i++)
+		vol->source_rfc1001_name[i] = toupper(nodename[i]);
+
+	vol->source_rfc1001_name[RFC1001_NAME_LEN] = 0;
+	/* null target name indicates to use *SMBSERVR default called name
+	   if we end up sending RFC1001 session initialize */
+	vol->target_rfc1001_name[0] = 0;
+	vol->cred_uid = current_uid();
+	vol->linux_uid = current_uid();
+	vol->linux_gid = current_gid();
+
+	/*
+	 * default to SFM style remapping of seven reserved characters
+	 * unless user overrides it or we negotiate CIFS POSIX where
+	 * it is unnecessary.  Can not simultaneously use more than one mapping
+	 * since then readdir could list files that open could not open
+	 */
+	vol->remap = true;
+
+	/* default to only allowing write access to owner of the mount */
+	vol->dir_mode = vol->file_mode = S_IRUGO | S_IXUGO | S_IWUSR;
+
+	/* vol->retry default is 0 (i.e. "soft" limited retry not hard retry) */
+	/* default is always to request posix paths. */
+	vol->posix_paths = 1;
+	/* default to using server inode numbers where available */
+	vol->server_ino = 1;
+
+	/* default is to use strict cifs caching semantics */
+	vol->strict_io = true;
+
+	vol->actimeo = CIFS_DEF_ACTIMEO;
+
+	/* offer SMB2.1 and later (SMB3 etc). Secure and widely accepted */
+	vol->ops = &smb30_operations;
+	vol->vals = &smbdefault_values;
+
+	vol->echo_interval = SMB_ECHO_INTERVAL_DEFAULT;
+
+	if (!mountdata)
+		goto cifs_parse_mount_err;
+
+	mountdata_copy = kstrndup(mountdata, PAGE_SIZE, GFP_KERNEL);
+	if (!mountdata_copy)
+		goto cifs_parse_mount_err;
+
+	options = mountdata_copy;
+	end = options + strlen(options);
+
+	if (strncmp(options, "sep=", 4) == 0) {
+		if (options[4] != 0) {
+			separator[0] = options[4];
+			options += 5;
+		} else {
+			cifs_dbg(FYI, "Null separator not allowed\n");
+		}
+	}
+	vol->backupuid_specified = false; /* no backup intent for a user */
+	vol->backupgid_specified = false; /* no backup intent for a group */
+
+	switch (cifs_parse_devname(devname, vol)) {
+	case 0:
+		break;
+	case -ENOMEM:
+		cifs_dbg(VFS, "Unable to allocate memory for devname.\n");
+		goto cifs_parse_mount_err;
+	case -EINVAL:
+		cifs_dbg(VFS, "Malformed UNC in devname.\n");
+		goto cifs_parse_mount_err;
+	default:
+		cifs_dbg(VFS, "Unknown error parsing devname.\n");
+		goto cifs_parse_mount_err;
+	}
+
+	while ((data = strsep(&options, separator)) != NULL) {
+		substring_t args[MAX_OPT_ARGS];
+		unsigned long option;
+		int token;
+
+		if (!*data)
+			continue;
+
+		token = match_token(data, cifs_mount_option_tokens, args);
+
+		switch (token) {
+
+		/* Ingnore the following */
+		case Opt_ignore:
+			break;
+
+		/* Boolean values */
+		case Opt_user_xattr:
+			vol->no_xattr = 0;
+			break;
+		case Opt_nouser_xattr:
+			vol->no_xattr = 1;
+			break;
+		case Opt_forceuid:
+			override_uid = 1;
+			break;
+		case Opt_noforceuid:
+			override_uid = 0;
+			break;
+		case Opt_forcegid:
+			override_gid = 1;
+			break;
+		case Opt_noforcegid:
+			override_gid = 0;
+			break;
+		case Opt_noblocksend:
+			vol->noblocksnd = 1;
+			break;
+		case Opt_noautotune:
+			vol->noautotune = 1;
+			break;
+		case Opt_nolease:
+			vol->no_lease = 1;
+			break;
+		case Opt_hard:
+			vol->retry = 1;
+			break;
+		case Opt_soft:
+			vol->retry = 0;
+			break;
+		case Opt_perm:
+			vol->noperm = 0;
+			break;
+		case Opt_noperm:
+			vol->noperm = 1;
+			break;
+		case Opt_mapchars:
+			vol->sfu_remap = true;
+			vol->remap = false; /* disable SFM mapping */
+			break;
+		case Opt_nomapchars:
+			vol->sfu_remap = false;
+			break;
+		case Opt_mapposix:
+			vol->remap = true;
+			vol->sfu_remap = false; /* disable SFU mapping */
+			break;
+		case Opt_nomapposix:
+			vol->remap = false;
+			break;
+		case Opt_sfu:
+			vol->sfu_emul = 1;
+			break;
+		case Opt_nosfu:
+			vol->sfu_emul = 0;
+			break;
+		case Opt_nodfs:
+			vol->nodfs = 1;
+			break;
+		case Opt_posixpaths:
+			vol->posix_paths = 1;
+			break;
+		case Opt_noposixpaths:
+			vol->posix_paths = 0;
+			break;
+		case Opt_nounix:
+			if (vol->linux_ext)
+				cifs_dbg(VFS,
+					"conflicting unix mount options\n");
+			vol->no_linux_ext = 1;
+			break;
+		case Opt_unix:
+			if (vol->no_linux_ext)
+				cifs_dbg(VFS,
+					"conflicting unix mount options\n");
+			vol->linux_ext = 1;
+			break;
+		case Opt_nocase:
+			vol->nocase = 1;
+			break;
+		case Opt_brl:
+			vol->nobrl =  0;
+			break;
+		case Opt_nobrl:
+			vol->nobrl =  1;
+			/*
+			 * turn off mandatory locking in mode
+			 * if remote locking is turned off since the
+			 * local vfs will do advisory
+			 */
+			if (vol->file_mode ==
+				(S_IALLUGO & ~(S_ISUID | S_IXGRP)))
+				vol->file_mode = S_IALLUGO;
+			break;
+		case Opt_nohandlecache:
+			vol->nohandlecache = 1;
+			break;
+		case Opt_handlecache:
+			vol->nohandlecache = 0;
+			break;
+		case Opt_forcemandatorylock:
+			vol->mand_lock = 1;
+			break;
+		case Opt_setuids:
+			vol->setuids = 1;
+			break;
+		case Opt_nosetuids:
+			vol->setuids = 0;
+			break;
+		case Opt_setuidfromacl:
+			vol->setuidfromacl = 1;
+			break;
+		case Opt_dynperm:
+			vol->dynperm = true;
+			break;
+		case Opt_nodynperm:
+			vol->dynperm = false;
+			break;
+		case Opt_nohard:
+			vol->retry = 0;
+			break;
+		case Opt_nosoft:
+			vol->retry = 1;
+			break;
+		case Opt_nointr:
+			vol->intr = 0;
+			break;
+		case Opt_intr:
+			vol->intr = 1;
+			break;
+		case Opt_nostrictsync:
+			vol->nostrictsync = 1;
+			break;
+		case Opt_strictsync:
+			vol->nostrictsync = 0;
+			break;
+		case Opt_serverino:
+			vol->server_ino = 1;
+			break;
+		case Opt_noserverino:
+			vol->server_ino = 0;
+			break;
+		case Opt_rwpidforward:
+			vol->rwpidforward = 1;
+			break;
+		case Opt_cifsacl:
+			vol->cifs_acl = 1;
+			break;
+		case Opt_nocifsacl:
+			vol->cifs_acl = 0;
+			break;
+		case Opt_acl:
+			vol->no_psx_acl = 0;
+			break;
+		case Opt_noacl:
+			vol->no_psx_acl = 1;
+			break;
+		case Opt_locallease:
+			vol->local_lease = 1;
+			break;
+		case Opt_sign:
+			vol->sign = true;
+			break;
+		case Opt_seal:
+			/* we do not do the following in secFlags because seal
+			 * is a per tree connection (mount) not a per socket
+			 * or per-smb connection option in the protocol
+			 * vol->secFlg |= CIFSSEC_MUST_SEAL;
+			 */
+			vol->seal = 1;
+			break;
+		case Opt_noac:
+			pr_warn("CIFS: Mount option noac not supported. Instead set /proc/fs/cifs/LookupCacheEnabled to 0\n");
+			break;
+		case Opt_fsc:
+#ifndef CONFIG_CIFS_FSCACHE
+			cifs_dbg(VFS, "FS-Cache support needs CONFIG_CIFS_FSCACHE kernel config option set\n");
+			goto cifs_parse_mount_err;
+#endif
+			vol->fsc = true;
+			break;
+		case Opt_mfsymlinks:
+			vol->mfsymlinks = true;
+			break;
+		case Opt_multiuser:
+			vol->multiuser = true;
+			break;
+		case Opt_sloppy:
+			sloppy = true;
+			break;
+		case Opt_nosharesock:
+			vol->nosharesock = true;
+			break;
+		case Opt_nopersistent:
+			vol->nopersistent = true;
+			if (vol->persistent) {
+				cifs_dbg(VFS,
+				  "persistenthandles mount options conflict\n");
+				goto cifs_parse_mount_err;
+			}
+			break;
+		case Opt_persistent:
+			vol->persistent = true;
+			if ((vol->nopersistent) || (vol->resilient)) {
+				cifs_dbg(VFS,
+				  "persistenthandles mount options conflict\n");
+				goto cifs_parse_mount_err;
+			}
+			break;
+		case Opt_resilient:
+			vol->resilient = true;
+			if (vol->persistent) {
+				cifs_dbg(VFS,
+				  "persistenthandles mount options conflict\n");
+				goto cifs_parse_mount_err;
+			}
+			break;
+		case Opt_noresilient:
+			vol->resilient = false; /* already the default */
+			break;
+		case Opt_domainauto:
+			vol->domainauto = true;
+			break;
+		case Opt_rdma:
+			vol->rdma = true;
+			break;
+
+		/* Numeric Values */
+		case Opt_backupuid:
+			if (get_option_uid(args, &vol->backupuid)) {
+				cifs_dbg(VFS, "%s: Invalid backupuid value\n",
+					 __func__);
+				goto cifs_parse_mount_err;
+			}
+			vol->backupuid_specified = true;
+			break;
+		case Opt_backupgid:
+			if (get_option_gid(args, &vol->backupgid)) {
+				cifs_dbg(VFS, "%s: Invalid backupgid value\n",
+					 __func__);
+				goto cifs_parse_mount_err;
+			}
+			vol->backupgid_specified = true;
+			break;
+		case Opt_uid:
+			if (get_option_uid(args, &vol->linux_uid)) {
+				cifs_dbg(VFS, "%s: Invalid uid value\n",
+					 __func__);
+				goto cifs_parse_mount_err;
+			}
+			uid_specified = true;
+			break;
+		case Opt_cruid:
+			if (get_option_uid(args, &vol->cred_uid)) {
+				cifs_dbg(VFS, "%s: Invalid cruid value\n",
+					 __func__);
+				goto cifs_parse_mount_err;
+			}
+			break;
+		case Opt_gid:
+			if (get_option_gid(args, &vol->linux_gid)) {
+				cifs_dbg(VFS, "%s: Invalid gid value\n",
+					 __func__);
+				goto cifs_parse_mount_err;
+			}
+			gid_specified = true;
+			break;
+		case Opt_file_mode:
+			if (get_option_ul(args, &option)) {
+				cifs_dbg(VFS, "%s: Invalid file_mode value\n",
+					 __func__);
+				goto cifs_parse_mount_err;
+			}
+			vol->file_mode = option;
+			break;
+		case Opt_dirmode:
+			if (get_option_ul(args, &option)) {
+				cifs_dbg(VFS, "%s: Invalid dir_mode value\n",
+					 __func__);
+				goto cifs_parse_mount_err;
+			}
+			vol->dir_mode = option;
+			break;
+		case Opt_port:
+			if (get_option_ul(args, &option) ||
+			    option > USHRT_MAX) {
+				cifs_dbg(VFS, "%s: Invalid port value\n",
+					 __func__);
+				goto cifs_parse_mount_err;
+			}
+			port = (unsigned short)option;
+			break;
+		case Opt_rsize:
+			if (get_option_ul(args, &option)) {
+				cifs_dbg(VFS, "%s: Invalid rsize value\n",
+					 __func__);
+				goto cifs_parse_mount_err;
+			}
+			vol->rsize = option;
+			break;
+		case Opt_wsize:
+			if (get_option_ul(args, &option)) {
+				cifs_dbg(VFS, "%s: Invalid wsize value\n",
+					 __func__);
+				goto cifs_parse_mount_err;
+			}
+			vol->wsize = option;
+			break;
+		case Opt_actimeo:
+			if (get_option_ul(args, &option)) {
+				cifs_dbg(VFS, "%s: Invalid actimeo value\n",
+					 __func__);
+				goto cifs_parse_mount_err;
+			}
+			vol->actimeo = HZ * option;
+			if (vol->actimeo > CIFS_MAX_ACTIMEO) {
+				cifs_dbg(VFS, "attribute cache timeout too large\n");
+				goto cifs_parse_mount_err;
+			}
+			break;
+		case Opt_echo_interval:
+			if (get_option_ul(args, &option)) {
+				cifs_dbg(VFS, "%s: Invalid echo interval value\n",
+					 __func__);
+				goto cifs_parse_mount_err;
+			}
+			vol->echo_interval = option;
+			break;
+		case Opt_snapshot:
+			if (get_option_ul(args, &option)) {
+				cifs_dbg(VFS, "%s: Invalid snapshot time\n",
+					 __func__);
+				goto cifs_parse_mount_err;
+			}
+			vol->snapshot_time = option;
+			break;
+		case Opt_max_credits:
+			if (get_option_ul(args, &option) || (option < 20) ||
+			    (option > 60000)) {
+				cifs_dbg(VFS, "%s: Invalid max_credits value\n",
+					 __func__);
+				goto cifs_parse_mount_err;
+			}
+			vol->max_credits = option;
+			break;
+
+		/* String Arguments */
+
+		case Opt_blank_user:
+			/* null user, ie. anonymous authentication */
+			vol->nullauth = 1;
+			vol->username = NULL;
+			break;
+		case Opt_user:
+			string = match_strdup(args);
+			if (string == NULL)
+				goto out_nomem;
+
+			if (strnlen(string, CIFS_MAX_USERNAME_LEN) >
+							CIFS_MAX_USERNAME_LEN) {
+				pr_warn("CIFS: username too long\n");
+				goto cifs_parse_mount_err;
+			}
+
+			kfree(vol->username);
+			vol->username = kstrdup(string, GFP_KERNEL);
+			if (!vol->username)
+				goto cifs_parse_mount_err;
+			break;
+		case Opt_blank_pass:
+			/* passwords have to be handled differently
+			 * to allow the character used for deliminator
+			 * to be passed within them
+			 */
+
+			/*
+			 * Check if this is a case where the  password
+			 * starts with a delimiter
+			 */
+			tmp_end = strchr(data, '=');
+			tmp_end++;
+			if (!(tmp_end < end && tmp_end[1] == delim)) {
+				/* No it is not. Set the password to NULL */
+				kzfree(vol->password);
+				vol->password = NULL;
+				break;
+			}
+			/* Yes it is. Drop down to Opt_pass below.*/
+		case Opt_pass:
+			/* Obtain the value string */
+			value = strchr(data, '=');
+			value++;
+
+			/* Set tmp_end to end of the string */
+			tmp_end = (char *) value + strlen(value);
+
+			/* Check if following character is the deliminator
+			 * If yes, we have encountered a double deliminator
+			 * reset the NULL character to the deliminator
+			 */
+			if (tmp_end < end && tmp_end[1] == delim) {
+				tmp_end[0] = delim;
+
+				/* Keep iterating until we get to a single
+				 * deliminator OR the end
+				 */
+				while ((tmp_end = strchr(tmp_end, delim))
+					!= NULL && (tmp_end[1] == delim)) {
+						tmp_end = (char *) &tmp_end[2];
+				}
+
+				/* Reset var options to point to next element */
+				if (tmp_end) {
+					tmp_end[0] = '\0';
+					options = (char *) &tmp_end[1];
+				} else
+					/* Reached the end of the mount option
+					 * string */
+					options = end;
+			}
+
+			kzfree(vol->password);
+			/* Now build new password string */
+			temp_len = strlen(value);
+			vol->password = kzalloc(temp_len+1, GFP_KERNEL);
+			if (vol->password == NULL) {
+				pr_warn("CIFS: no memory for password\n");
+				goto cifs_parse_mount_err;
+			}
+
+			for (i = 0, j = 0; i < temp_len; i++, j++) {
+				vol->password[j] = value[i];
+				if ((value[i] == delim) &&
+				     value[i+1] == delim)
+					/* skip the second deliminator */
+					i++;
+			}
+			vol->password[j] = '\0';
+			break;
+		case Opt_blank_ip:
+			/* FIXME: should this be an error instead? */
+			got_ip = false;
+			break;
+		case Opt_ip:
+			string = match_strdup(args);
+			if (string == NULL)
+				goto out_nomem;
+
+			if (!cifs_convert_address(dstaddr, string,
+					strlen(string))) {
+				pr_err("CIFS: bad ip= option (%s).\n", string);
+				goto cifs_parse_mount_err;
+			}
+			got_ip = true;
+			break;
+		case Opt_domain:
+			string = match_strdup(args);
+			if (string == NULL)
+				goto out_nomem;
+
+			if (strnlen(string, CIFS_MAX_DOMAINNAME_LEN)
+					== CIFS_MAX_DOMAINNAME_LEN) {
+				pr_warn("CIFS: domain name too long\n");
+				goto cifs_parse_mount_err;
+			}
+
+			kfree(vol->domainname);
+			vol->domainname = kstrdup(string, GFP_KERNEL);
+			if (!vol->domainname) {
+				pr_warn("CIFS: no memory for domainname\n");
+				goto cifs_parse_mount_err;
+			}
+			cifs_dbg(FYI, "Domain name set\n");
+			break;
+		case Opt_srcaddr:
+			string = match_strdup(args);
+			if (string == NULL)
+				goto out_nomem;
+
+			if (!cifs_convert_address(
+					(struct sockaddr *)&vol->srcaddr,
+					string, strlen(string))) {
+				pr_warn("CIFS: Could not parse srcaddr: %s\n",
+					string);
+				goto cifs_parse_mount_err;
+			}
+			break;
+		case Opt_iocharset:
+			string = match_strdup(args);
+			if (string == NULL)
+				goto out_nomem;
+
+			if (strnlen(string, 1024) >= 65) {
+				pr_warn("CIFS: iocharset name too long.\n");
+				goto cifs_parse_mount_err;
+			}
+
+			 if (strncasecmp(string, "default", 7) != 0) {
+				kfree(vol->iocharset);
+				vol->iocharset = kstrdup(string,
+							 GFP_KERNEL);
+				if (!vol->iocharset) {
+					pr_warn("CIFS: no memory for charset\n");
+					goto cifs_parse_mount_err;
+				}
+			}
+			/* if iocharset not set then load_nls_default
+			 * is used by caller
+			 */
+			 cifs_dbg(FYI, "iocharset set to %s\n", string);
+			break;
+		case Opt_netbiosname:
+			string = match_strdup(args);
+			if (string == NULL)
+				goto out_nomem;
+
+			memset(vol->source_rfc1001_name, 0x20,
+				RFC1001_NAME_LEN);
+			/*
+			 * FIXME: are there cases in which a comma can
+			 * be valid in workstation netbios name (and
+			 * need special handling)?
+			 */
+			for (i = 0; i < RFC1001_NAME_LEN; i++) {
+				/* don't ucase netbiosname for user */
+				if (string[i] == 0)
+					break;
+				vol->source_rfc1001_name[i] = string[i];
+			}
+			/* The string has 16th byte zero still from
+			 * set at top of the function
+			 */
+			if (i == RFC1001_NAME_LEN && string[i] != 0)
+				pr_warn("CIFS: netbiosname longer than 15 truncated.\n");
+			break;
+		case Opt_servern:
+			/* servernetbiosname specified override *SMBSERVER */
+			string = match_strdup(args);
+			if (string == NULL)
+				goto out_nomem;
+
+			/* last byte, type, is 0x20 for servr type */
+			memset(vol->target_rfc1001_name, 0x20,
+				RFC1001_NAME_LEN_WITH_NULL);
+
+			/* BB are there cases in which a comma can be
+			   valid in this workstation netbios name
+			   (and need special handling)? */
+
+			/* user or mount helper must uppercase the
+			   netbios name */
+			for (i = 0; i < 15; i++) {
+				if (string[i] == 0)
+					break;
+				vol->target_rfc1001_name[i] = string[i];
+			}
+			/* The string has 16th byte zero still from
+			   set at top of the function  */
+			if (i == RFC1001_NAME_LEN && string[i] != 0)
+				pr_warn("CIFS: server netbiosname longer than 15 truncated.\n");
+			break;
+		case Opt_ver:
+			/* version of mount userspace tools, not dialect */
+			string = match_strdup(args);
+			if (string == NULL)
+				goto out_nomem;
+
+			/* If interface changes in mount.cifs bump to new ver */
+			if (strncasecmp(string, "1", 1) == 0) {
+				if (strlen(string) > 1) {
+					pr_warn("Bad mount helper ver=%s. Did "
+						"you want SMB1 (CIFS) dialect "
+						"and mean to type vers=1.0 "
+						"instead?\n", string);
+					goto cifs_parse_mount_err;
+				}
+				/* This is the default */
+				break;
+			}
+			/* For all other value, error */
+			pr_warn("CIFS: Invalid mount helper version specified\n");
+			goto cifs_parse_mount_err;
+		case Opt_vers:
+			/* protocol version (dialect) */
+			string = match_strdup(args);
+			if (string == NULL)
+				goto out_nomem;
+
+			if (cifs_parse_smb_version(string, vol, is_smb3) != 0)
+				goto cifs_parse_mount_err;
+			got_version = true;
+			break;
+		case Opt_sec:
+			string = match_strdup(args);
+			if (string == NULL)
+				goto out_nomem;
+
+			if (cifs_parse_security_flavors(string, vol) != 0)
+				goto cifs_parse_mount_err;
+			break;
+		case Opt_cache:
+			string = match_strdup(args);
+			if (string == NULL)
+				goto out_nomem;
+
+			if (cifs_parse_cache_flavor(string, vol) != 0)
+				goto cifs_parse_mount_err;
+			break;
+		default:
+			/*
+			 * An option we don't recognize. Save it off for later
+			 * if we haven't already found one
+			 */
+			if (!invalid)
+				invalid = data;
+			break;
+		}
+		/* Free up any allocated string */
+		kfree(string);
+		string = NULL;
+	}
+
+	if (!sloppy && invalid) {
+		pr_err("CIFS: Unknown mount option \"%s\"\n", invalid);
+		goto cifs_parse_mount_err;
+	}
+
+	if (vol->rdma && vol->vals->protocol_id < SMB30_PROT_ID) {
+		cifs_dbg(VFS, "SMB Direct requires Version >=3.0\n");
+		goto cifs_parse_mount_err;
+	}
+
+#ifndef CONFIG_KEYS
+	/* Muliuser mounts require CONFIG_KEYS support */
+	if (vol->multiuser) {
+		cifs_dbg(VFS, "Multiuser mounts require kernels with CONFIG_KEYS enabled\n");
+		goto cifs_parse_mount_err;
+	}
+#endif
+	if (!vol->UNC) {
+		cifs_dbg(VFS, "CIFS mount error: No usable UNC path provided in device string!\n");
+		goto cifs_parse_mount_err;
+	}
+
+	/* make sure UNC has a share name */
+	if (!strchr(vol->UNC + 3, '\\')) {
+		cifs_dbg(VFS, "Malformed UNC. Unable to find share name.\n");
+		goto cifs_parse_mount_err;
+	}
+
+	if (!got_ip) {
+		int len;
+		const char *slash;
+
+		/* No ip= option specified? Try to get it from UNC */
+		/* Use the address part of the UNC. */
+		slash = strchr(&vol->UNC[2], '\\');
+		len = slash - &vol->UNC[2];
+		if (!cifs_convert_address(dstaddr, &vol->UNC[2], len)) {
+			pr_err("Unable to determine destination address.\n");
+			goto cifs_parse_mount_err;
+		}
+	}
+
+	/* set the port that we got earlier */
+	cifs_set_port(dstaddr, port);
+
+	if (uid_specified)
+		vol->override_uid = override_uid;
+	else if (override_uid == 1)
+		pr_notice("CIFS: ignoring forceuid mount option specified with no uid= option.\n");
+
+	if (gid_specified)
+		vol->override_gid = override_gid;
+	else if (override_gid == 1)
+		pr_notice("CIFS: ignoring forcegid mount option specified with no gid= option.\n");
+
+	if (got_version == false)
+		pr_warn("No dialect specified on mount. Default has changed to "
+			"a more secure dialect, SMB2.1 or later (e.g. SMB3), from CIFS "
+			"(SMB1). To use the less secure SMB1 dialect to access "
+			"old servers which do not support SMB3 (or SMB2.1) specify vers=1.0"
+			" on mount.\n");
+
+	kfree(mountdata_copy);
+	return 0;
+
+out_nomem:
+	pr_warn("Could not allocate temporary buffer\n");
+cifs_parse_mount_err:
+	kfree(string);
+	kfree(mountdata_copy);
+	return 1;
+}
+
+/** Returns true if srcaddr isn't specified and rhs isn't
+ * specified, or if srcaddr is specified and
+ * matches the IP address of the rhs argument.
+ */
+static bool
+srcip_matches(struct sockaddr *srcaddr, struct sockaddr *rhs)
+{
+	switch (srcaddr->sa_family) {
+	case AF_UNSPEC:
+		return (rhs->sa_family == AF_UNSPEC);
+	case AF_INET: {
+		struct sockaddr_in *saddr4 = (struct sockaddr_in *)srcaddr;
+		struct sockaddr_in *vaddr4 = (struct sockaddr_in *)rhs;
+		return (saddr4->sin_addr.s_addr == vaddr4->sin_addr.s_addr);
+	}
+	case AF_INET6: {
+		struct sockaddr_in6 *saddr6 = (struct sockaddr_in6 *)srcaddr;
+		struct sockaddr_in6 *vaddr6 = (struct sockaddr_in6 *)rhs;
+		return ipv6_addr_equal(&saddr6->sin6_addr, &vaddr6->sin6_addr);
+	}
+	default:
+		WARN_ON(1);
+		return false; /* don't expect to be here */
+	}
+}
+
+/*
+ * If no port is specified in addr structure, we try to match with 445 port
+ * and if it fails - with 139 ports. It should be called only if address
+ * families of server and addr are equal.
+ */
+static bool
+match_port(struct TCP_Server_Info *server, struct sockaddr *addr)
+{
+	__be16 port, *sport;
+
+	switch (addr->sa_family) {
+	case AF_INET:
+		sport = &((struct sockaddr_in *) &server->dstaddr)->sin_port;
+		port = ((struct sockaddr_in *) addr)->sin_port;
+		break;
+	case AF_INET6:
+		sport = &((struct sockaddr_in6 *) &server->dstaddr)->sin6_port;
+		port = ((struct sockaddr_in6 *) addr)->sin6_port;
+		break;
+	default:
+		WARN_ON(1);
+		return false;
+	}
+
+	if (!port) {
+		port = htons(CIFS_PORT);
+		if (port == *sport)
+			return true;
+
+		port = htons(RFC1001_PORT);
+	}
+
+	return port == *sport;
+}
+
+static bool
+match_address(struct TCP_Server_Info *server, struct sockaddr *addr,
+	      struct sockaddr *srcaddr)
+{
+	switch (addr->sa_family) {
+	case AF_INET: {
+		struct sockaddr_in *addr4 = (struct sockaddr_in *)addr;
+		struct sockaddr_in *srv_addr4 =
+					(struct sockaddr_in *)&server->dstaddr;
+
+		if (addr4->sin_addr.s_addr != srv_addr4->sin_addr.s_addr)
+			return false;
+		break;
+	}
+	case AF_INET6: {
+		struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)addr;
+		struct sockaddr_in6 *srv_addr6 =
+					(struct sockaddr_in6 *)&server->dstaddr;
+
+		if (!ipv6_addr_equal(&addr6->sin6_addr,
+				     &srv_addr6->sin6_addr))
+			return false;
+		if (addr6->sin6_scope_id != srv_addr6->sin6_scope_id)
+			return false;
+		break;
+	}
+	default:
+		WARN_ON(1);
+		return false; /* don't expect to be here */
+	}
+
+	if (!srcip_matches(srcaddr, (struct sockaddr *)&server->srcaddr))
+		return false;
+
+	return true;
+}
+
+static bool
+match_security(struct TCP_Server_Info *server, struct smb_vol *vol)
+{
+	/*
+	 * The select_sectype function should either return the vol->sectype
+	 * that was specified, or "Unspecified" if that sectype was not
+	 * compatible with the given NEGOTIATE request.
+	 */
+	if (server->ops->select_sectype(server, vol->sectype)
+	     == Unspecified)
+		return false;
+
+	/*
+	 * Now check if signing mode is acceptable. No need to check
+	 * global_secflags at this point since if MUST_SIGN is set then
+	 * the server->sign had better be too.
+	 */
+	if (vol->sign && !server->sign)
+		return false;
+
+	return true;
+}
+
+static int match_server(struct TCP_Server_Info *server, struct smb_vol *vol)
+{
+	struct sockaddr *addr = (struct sockaddr *)&vol->dstaddr;
+
+	if (vol->nosharesock)
+		return 0;
+
+	/* BB update this for smb3any and default case */
+	if ((server->vals != vol->vals) || (server->ops != vol->ops))
+		return 0;
+
+	if (!net_eq(cifs_net_ns(server), current->nsproxy->net_ns))
+		return 0;
+
+	if (!match_address(server, addr,
+			   (struct sockaddr *)&vol->srcaddr))
+		return 0;
+
+	if (!match_port(server, addr))
+		return 0;
+
+	if (!match_security(server, vol))
+		return 0;
+
+	if (server->echo_interval != vol->echo_interval * HZ)
+		return 0;
+
+	if (server->rdma != vol->rdma)
+		return 0;
+
+	return 1;
+}
+
+static struct TCP_Server_Info *
+cifs_find_tcp_session(struct smb_vol *vol)
+{
+	struct TCP_Server_Info *server;
+
+	spin_lock(&cifs_tcp_ses_lock);
+	list_for_each_entry(server, &cifs_tcp_ses_list, tcp_ses_list) {
+		if (!match_server(server, vol))
+			continue;
+
+		++server->srv_count;
+		spin_unlock(&cifs_tcp_ses_lock);
+		cifs_dbg(FYI, "Existing tcp session with server found\n");
+		return server;
+	}
+	spin_unlock(&cifs_tcp_ses_lock);
+	return NULL;
+}
+
+void
+cifs_put_tcp_session(struct TCP_Server_Info *server, int from_reconnect)
+{
+	struct task_struct *task;
+
+	spin_lock(&cifs_tcp_ses_lock);
+	if (--server->srv_count > 0) {
+		spin_unlock(&cifs_tcp_ses_lock);
+		return;
+	}
+
+	put_net(cifs_net_ns(server));
+
+	list_del_init(&server->tcp_ses_list);
+	spin_unlock(&cifs_tcp_ses_lock);
+
+	cancel_delayed_work_sync(&server->echo);
+
+	if (from_reconnect)
+		/*
+		 * Avoid deadlock here: reconnect work calls
+		 * cifs_put_tcp_session() at its end. Need to be sure
+		 * that reconnect work does nothing with server pointer after
+		 * that step.
+		 */
+		cancel_delayed_work(&server->reconnect);
+	else
+		cancel_delayed_work_sync(&server->reconnect);
+
+	spin_lock(&GlobalMid_Lock);
+	server->tcpStatus = CifsExiting;
+	spin_unlock(&GlobalMid_Lock);
+
+	cifs_crypto_secmech_release(server);
+	cifs_fscache_release_client_cookie(server);
+
+	kfree(server->session_key.response);
+	server->session_key.response = NULL;
+	server->session_key.len = 0;
+
+	task = xchg(&server->tsk, NULL);
+	if (task)
+		send_sig(SIGKILL, task, 1);
+}
+
+static struct TCP_Server_Info *
+cifs_get_tcp_session(struct smb_vol *volume_info)
+{
+	struct TCP_Server_Info *tcp_ses = NULL;
+	int rc;
+
+	cifs_dbg(FYI, "UNC: %s\n", volume_info->UNC);
+
+	/* see if we already have a matching tcp_ses */
+	tcp_ses = cifs_find_tcp_session(volume_info);
+	if (tcp_ses)
+		return tcp_ses;
+
+	tcp_ses = kzalloc(sizeof(struct TCP_Server_Info), GFP_KERNEL);
+	if (!tcp_ses) {
+		rc = -ENOMEM;
+		goto out_err;
+	}
+
+	tcp_ses->ops = volume_info->ops;
+	tcp_ses->vals = volume_info->vals;
+	cifs_set_net_ns(tcp_ses, get_net(current->nsproxy->net_ns));
+	tcp_ses->hostname = extract_hostname(volume_info->UNC);
+	if (IS_ERR(tcp_ses->hostname)) {
+		rc = PTR_ERR(tcp_ses->hostname);
+		goto out_err_crypto_release;
+	}
+
+	tcp_ses->noblocksnd = volume_info->noblocksnd;
+	tcp_ses->noautotune = volume_info->noautotune;
+	tcp_ses->tcp_nodelay = volume_info->sockopt_tcp_nodelay;
+	tcp_ses->rdma = volume_info->rdma;
+	tcp_ses->in_flight = 0;
+	tcp_ses->credits = 1;
+	init_waitqueue_head(&tcp_ses->response_q);
+	init_waitqueue_head(&tcp_ses->request_q);
+	INIT_LIST_HEAD(&tcp_ses->pending_mid_q);
+	mutex_init(&tcp_ses->srv_mutex);
+	memcpy(tcp_ses->workstation_RFC1001_name,
+		volume_info->source_rfc1001_name, RFC1001_NAME_LEN_WITH_NULL);
+	memcpy(tcp_ses->server_RFC1001_name,
+		volume_info->target_rfc1001_name, RFC1001_NAME_LEN_WITH_NULL);
+	tcp_ses->session_estab = false;
+	tcp_ses->sequence_number = 0;
+	tcp_ses->lstrp = jiffies;
+	spin_lock_init(&tcp_ses->req_lock);
+	INIT_LIST_HEAD(&tcp_ses->tcp_ses_list);
+	INIT_LIST_HEAD(&tcp_ses->smb_ses_list);
+	INIT_DELAYED_WORK(&tcp_ses->echo, cifs_echo_request);
+	INIT_DELAYED_WORK(&tcp_ses->reconnect, smb2_reconnect_server);
+	mutex_init(&tcp_ses->reconnect_mutex);
+	memcpy(&tcp_ses->srcaddr, &volume_info->srcaddr,
+	       sizeof(tcp_ses->srcaddr));
+	memcpy(&tcp_ses->dstaddr, &volume_info->dstaddr,
+		sizeof(tcp_ses->dstaddr));
+	generate_random_uuid(tcp_ses->client_guid);
+	/*
+	 * at this point we are the only ones with the pointer
+	 * to the struct since the kernel thread not created yet
+	 * no need to spinlock this init of tcpStatus or srv_count
+	 */
+	tcp_ses->tcpStatus = CifsNew;
+	++tcp_ses->srv_count;
+
+	if (volume_info->echo_interval >= SMB_ECHO_INTERVAL_MIN &&
+		volume_info->echo_interval <= SMB_ECHO_INTERVAL_MAX)
+		tcp_ses->echo_interval = volume_info->echo_interval * HZ;
+	else
+		tcp_ses->echo_interval = SMB_ECHO_INTERVAL_DEFAULT * HZ;
+	if (tcp_ses->rdma) {
+#ifndef CONFIG_CIFS_SMB_DIRECT
+		cifs_dbg(VFS, "CONFIG_CIFS_SMB_DIRECT is not enabled\n");
+		rc = -ENOENT;
+		goto out_err_crypto_release;
+#endif
+		tcp_ses->smbd_conn = smbd_get_connection(
+			tcp_ses, (struct sockaddr *)&volume_info->dstaddr);
+		if (tcp_ses->smbd_conn) {
+			cifs_dbg(VFS, "RDMA transport established\n");
+			rc = 0;
+			goto smbd_connected;
+		} else {
+			rc = -ENOENT;
+			goto out_err_crypto_release;
+		}
+	}
+	rc = ip_connect(tcp_ses);
+	if (rc < 0) {
+		cifs_dbg(VFS, "Error connecting to socket. Aborting operation.\n");
+		goto out_err_crypto_release;
+	}
+smbd_connected:
+	/*
+	 * since we're in a cifs function already, we know that
+	 * this will succeed. No need for try_module_get().
+	 */
+	__module_get(THIS_MODULE);
+	tcp_ses->tsk = kthread_run(cifs_demultiplex_thread,
+				  tcp_ses, "cifsd");
+	if (IS_ERR(tcp_ses->tsk)) {
+		rc = PTR_ERR(tcp_ses->tsk);
+		cifs_dbg(VFS, "error %d create cifsd thread\n", rc);
+		module_put(THIS_MODULE);
+		goto out_err_crypto_release;
+	}
+	tcp_ses->tcpStatus = CifsNeedNegotiate;
+
+	/* thread spawned, put it on the list */
+	spin_lock(&cifs_tcp_ses_lock);
+	list_add(&tcp_ses->tcp_ses_list, &cifs_tcp_ses_list);
+	spin_unlock(&cifs_tcp_ses_lock);
+
+	cifs_fscache_get_client_cookie(tcp_ses);
+
+	/* queue echo request delayed work */
+	queue_delayed_work(cifsiod_wq, &tcp_ses->echo, tcp_ses->echo_interval);
+
+	return tcp_ses;
+
+out_err_crypto_release:
+	cifs_crypto_secmech_release(tcp_ses);
+
+	put_net(cifs_net_ns(tcp_ses));
+
+out_err:
+	if (tcp_ses) {
+		if (!IS_ERR(tcp_ses->hostname))
+			kfree(tcp_ses->hostname);
+		if (tcp_ses->ssocket)
+			sock_release(tcp_ses->ssocket);
+		kfree(tcp_ses);
+	}
+	return ERR_PTR(rc);
+}
+
+static int match_session(struct cifs_ses *ses, struct smb_vol *vol)
+{
+	if (vol->sectype != Unspecified &&
+	    vol->sectype != ses->sectype)
+		return 0;
+
+	switch (ses->sectype) {
+	case Kerberos:
+		if (!uid_eq(vol->cred_uid, ses->cred_uid))
+			return 0;
+		break;
+	default:
+		/* NULL username means anonymous session */
+		if (ses->user_name == NULL) {
+			if (!vol->nullauth)
+				return 0;
+			break;
+		}
+
+		/* anything else takes username/password */
+		if (strncmp(ses->user_name,
+			    vol->username ? vol->username : "",
+			    CIFS_MAX_USERNAME_LEN))
+			return 0;
+		if ((vol->username && strlen(vol->username) != 0) &&
+		    ses->password != NULL &&
+		    strncmp(ses->password,
+			    vol->password ? vol->password : "",
+			    CIFS_MAX_PASSWORD_LEN))
+			return 0;
+	}
+	return 1;
+}
+
+/**
+ * cifs_setup_ipc - helper to setup the IPC tcon for the session
+ *
+ * A new IPC connection is made and stored in the session
+ * tcon_ipc. The IPC tcon has the same lifetime as the session.
+ */
+static int
+cifs_setup_ipc(struct cifs_ses *ses, struct smb_vol *volume_info)
+{
+	int rc = 0, xid;
+	struct cifs_tcon *tcon;
+	struct nls_table *nls_codepage;
+	char unc[SERVER_NAME_LENGTH + sizeof("//x/IPC$")] = {0};
+	bool seal = false;
+
+	/*
+	 * If the mount request that resulted in the creation of the
+	 * session requires encryption, force IPC to be encrypted too.
+	 */
+	if (volume_info->seal) {
+		if (ses->server->capabilities & SMB2_GLOBAL_CAP_ENCRYPTION)
+			seal = true;
+		else {
+			cifs_dbg(VFS,
+				 "IPC: server doesn't support encryption\n");
+			return -EOPNOTSUPP;
+		}
+	}
+
+	tcon = tconInfoAlloc();
+	if (tcon == NULL)
+		return -ENOMEM;
+
+	snprintf(unc, sizeof(unc), "\\\\%s\\IPC$", ses->server->hostname);
+
+	/* cannot fail */
+	nls_codepage = load_nls_default();
+
+	xid = get_xid();
+	tcon->ses = ses;
+	tcon->ipc = true;
+	tcon->seal = seal;
+	rc = ses->server->ops->tree_connect(xid, ses, unc, tcon, nls_codepage);
+	free_xid(xid);
+
+	if (rc) {
+		cifs_dbg(VFS, "failed to connect to IPC (rc=%d)\n", rc);
+		tconInfoFree(tcon);
+		goto out;
+	}
+
+	cifs_dbg(FYI, "IPC tcon rc = %d ipc tid = %d\n", rc, tcon->tid);
+
+	ses->tcon_ipc = tcon;
+out:
+	unload_nls(nls_codepage);
+	return rc;
+}
+
+/**
+ * cifs_free_ipc - helper to release the session IPC tcon
+ *
+ * Needs to be called everytime a session is destroyed
+ */
+static int
+cifs_free_ipc(struct cifs_ses *ses)
+{
+	int rc = 0, xid;
+	struct cifs_tcon *tcon = ses->tcon_ipc;
+
+	if (tcon == NULL)
+		return 0;
+
+	if (ses->server->ops->tree_disconnect) {
+		xid = get_xid();
+		rc = ses->server->ops->tree_disconnect(xid, tcon);
+		free_xid(xid);
+	}
+
+	if (rc)
+		cifs_dbg(FYI, "failed to disconnect IPC tcon (rc=%d)\n", rc);
+
+	tconInfoFree(tcon);
+	ses->tcon_ipc = NULL;
+	return rc;
+}
+
+static struct cifs_ses *
+cifs_find_smb_ses(struct TCP_Server_Info *server, struct smb_vol *vol)
+{
+	struct cifs_ses *ses;
+
+	spin_lock(&cifs_tcp_ses_lock);
+	list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
+		if (ses->status == CifsExiting)
+			continue;
+		if (!match_session(ses, vol))
+			continue;
+		++ses->ses_count;
+		spin_unlock(&cifs_tcp_ses_lock);
+		return ses;
+	}
+	spin_unlock(&cifs_tcp_ses_lock);
+	return NULL;
+}
+
+static void
+cifs_put_smb_ses(struct cifs_ses *ses)
+{
+	unsigned int rc, xid;
+	struct TCP_Server_Info *server = ses->server;
+
+	cifs_dbg(FYI, "%s: ses_count=%d\n", __func__, ses->ses_count);
+
+	spin_lock(&cifs_tcp_ses_lock);
+	if (ses->status == CifsExiting) {
+		spin_unlock(&cifs_tcp_ses_lock);
+		return;
+	}
+	if (--ses->ses_count > 0) {
+		spin_unlock(&cifs_tcp_ses_lock);
+		return;
+	}
+	if (ses->status == CifsGood)
+		ses->status = CifsExiting;
+	spin_unlock(&cifs_tcp_ses_lock);
+
+	cifs_free_ipc(ses);
+
+	if (ses->status == CifsExiting && server->ops->logoff) {
+		xid = get_xid();
+		rc = server->ops->logoff(xid, ses);
+		if (rc)
+			cifs_dbg(VFS, "%s: Session Logoff failure rc=%d\n",
+				__func__, rc);
+		_free_xid(xid);
+	}
+
+	spin_lock(&cifs_tcp_ses_lock);
+	list_del_init(&ses->smb_ses_list);
+	spin_unlock(&cifs_tcp_ses_lock);
+
+	sesInfoFree(ses);
+	cifs_put_tcp_session(server, 0);
+}
+
+#ifdef CONFIG_KEYS
+
+/* strlen("cifs:a:") + CIFS_MAX_DOMAINNAME_LEN + 1 */
+#define CIFSCREDS_DESC_SIZE (7 + CIFS_MAX_DOMAINNAME_LEN + 1)
+
+/* Populate username and pw fields from keyring if possible */
+static int
+cifs_set_cifscreds(struct smb_vol *vol, struct cifs_ses *ses)
+{
+	int rc = 0;
+	int is_domain = 0;
+	const char *delim, *payload;
+	char *desc;
+	ssize_t len;
+	struct key *key;
+	struct TCP_Server_Info *server = ses->server;
+	struct sockaddr_in *sa;
+	struct sockaddr_in6 *sa6;
+	const struct user_key_payload *upayload;
+
+	desc = kmalloc(CIFSCREDS_DESC_SIZE, GFP_KERNEL);
+	if (!desc)
+		return -ENOMEM;
+
+	/* try to find an address key first */
+	switch (server->dstaddr.ss_family) {
+	case AF_INET:
+		sa = (struct sockaddr_in *)&server->dstaddr;
+		sprintf(desc, "cifs:a:%pI4", &sa->sin_addr.s_addr);
+		break;
+	case AF_INET6:
+		sa6 = (struct sockaddr_in6 *)&server->dstaddr;
+		sprintf(desc, "cifs:a:%pI6c", &sa6->sin6_addr.s6_addr);
+		break;
+	default:
+		cifs_dbg(FYI, "Bad ss_family (%hu)\n",
+			 server->dstaddr.ss_family);
+		rc = -EINVAL;
+		goto out_err;
+	}
+
+	cifs_dbg(FYI, "%s: desc=%s\n", __func__, desc);
+	key = request_key(&key_type_logon, desc, "");
+	if (IS_ERR(key)) {
+		if (!ses->domainName) {
+			cifs_dbg(FYI, "domainName is NULL\n");
+			rc = PTR_ERR(key);
+			goto out_err;
+		}
+
+		/* didn't work, try to find a domain key */
+		sprintf(desc, "cifs:d:%s", ses->domainName);
+		cifs_dbg(FYI, "%s: desc=%s\n", __func__, desc);
+		key = request_key(&key_type_logon, desc, "");
+		if (IS_ERR(key)) {
+			rc = PTR_ERR(key);
+			goto out_err;
+		}
+		is_domain = 1;
+	}
+
+	down_read(&key->sem);
+	upayload = user_key_payload_locked(key);
+	if (IS_ERR_OR_NULL(upayload)) {
+		rc = upayload ? PTR_ERR(upayload) : -EINVAL;
+		goto out_key_put;
+	}
+
+	/* find first : in payload */
+	payload = upayload->data;
+	delim = strnchr(payload, upayload->datalen, ':');
+	cifs_dbg(FYI, "payload=%s\n", payload);
+	if (!delim) {
+		cifs_dbg(FYI, "Unable to find ':' in payload (datalen=%d)\n",
+			 upayload->datalen);
+		rc = -EINVAL;
+		goto out_key_put;
+	}
+
+	len = delim - payload;
+	if (len > CIFS_MAX_USERNAME_LEN || len <= 0) {
+		cifs_dbg(FYI, "Bad value from username search (len=%zd)\n",
+			 len);
+		rc = -EINVAL;
+		goto out_key_put;
+	}
+
+	vol->username = kstrndup(payload, len, GFP_KERNEL);
+	if (!vol->username) {
+		cifs_dbg(FYI, "Unable to allocate %zd bytes for username\n",
+			 len);
+		rc = -ENOMEM;
+		goto out_key_put;
+	}
+	cifs_dbg(FYI, "%s: username=%s\n", __func__, vol->username);
+
+	len = key->datalen - (len + 1);
+	if (len > CIFS_MAX_PASSWORD_LEN || len <= 0) {
+		cifs_dbg(FYI, "Bad len for password search (len=%zd)\n", len);
+		rc = -EINVAL;
+		kfree(vol->username);
+		vol->username = NULL;
+		goto out_key_put;
+	}
+
+	++delim;
+	vol->password = kstrndup(delim, len, GFP_KERNEL);
+	if (!vol->password) {
+		cifs_dbg(FYI, "Unable to allocate %zd bytes for password\n",
+			 len);
+		rc = -ENOMEM;
+		kfree(vol->username);
+		vol->username = NULL;
+		goto out_key_put;
+	}
+
+	/*
+	 * If we have a domain key then we must set the domainName in the
+	 * for the request.
+	 */
+	if (is_domain && ses->domainName) {
+		vol->domainname = kstrndup(ses->domainName,
+					   strlen(ses->domainName),
+					   GFP_KERNEL);
+		if (!vol->domainname) {
+			cifs_dbg(FYI, "Unable to allocate %zd bytes for "
+				 "domain\n", len);
+			rc = -ENOMEM;
+			kfree(vol->username);
+			vol->username = NULL;
+			kzfree(vol->password);
+			vol->password = NULL;
+			goto out_key_put;
+		}
+	}
+
+out_key_put:
+	up_read(&key->sem);
+	key_put(key);
+out_err:
+	kfree(desc);
+	cifs_dbg(FYI, "%s: returning %d\n", __func__, rc);
+	return rc;
+}
+#else /* ! CONFIG_KEYS */
+static inline int
+cifs_set_cifscreds(struct smb_vol *vol __attribute__((unused)),
+		   struct cifs_ses *ses __attribute__((unused)))
+{
+	return -ENOSYS;
+}
+#endif /* CONFIG_KEYS */
+
+/**
+ * cifs_get_smb_ses - get a session matching @volume_info data from @server
+ *
+ * This function assumes it is being called from cifs_mount() where we
+ * already got a server reference (server refcount +1). See
+ * cifs_get_tcon() for refcount explanations.
+ */
+static struct cifs_ses *
+cifs_get_smb_ses(struct TCP_Server_Info *server, struct smb_vol *volume_info)
+{
+	int rc = -ENOMEM;
+	unsigned int xid;
+	struct cifs_ses *ses;
+	struct sockaddr_in *addr = (struct sockaddr_in *)&server->dstaddr;
+	struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)&server->dstaddr;
+
+	xid = get_xid();
+
+	ses = cifs_find_smb_ses(server, volume_info);
+	if (ses) {
+		cifs_dbg(FYI, "Existing smb sess found (status=%d)\n",
+			 ses->status);
+
+		mutex_lock(&ses->session_mutex);
+		rc = cifs_negotiate_protocol(xid, ses);
+		if (rc) {
+			mutex_unlock(&ses->session_mutex);
+			/* problem -- put our ses reference */
+			cifs_put_smb_ses(ses);
+			free_xid(xid);
+			return ERR_PTR(rc);
+		}
+		if (ses->need_reconnect) {
+			cifs_dbg(FYI, "Session needs reconnect\n");
+			rc = cifs_setup_session(xid, ses,
+						volume_info->local_nls);
+			if (rc) {
+				mutex_unlock(&ses->session_mutex);
+				/* problem -- put our reference */
+				cifs_put_smb_ses(ses);
+				free_xid(xid);
+				return ERR_PTR(rc);
+			}
+		}
+		mutex_unlock(&ses->session_mutex);
+
+		/* existing SMB ses has a server reference already */
+		cifs_put_tcp_session(server, 0);
+		free_xid(xid);
+		return ses;
+	}
+
+	cifs_dbg(FYI, "Existing smb sess not found\n");
+	ses = sesInfoAlloc();
+	if (ses == NULL)
+		goto get_ses_fail;
+
+	/* new SMB session uses our server ref */
+	ses->server = server;
+	if (server->dstaddr.ss_family == AF_INET6)
+		sprintf(ses->serverName, "%pI6", &addr6->sin6_addr);
+	else
+		sprintf(ses->serverName, "%pI4", &addr->sin_addr);
+
+	if (volume_info->username) {
+		ses->user_name = kstrdup(volume_info->username, GFP_KERNEL);
+		if (!ses->user_name)
+			goto get_ses_fail;
+	}
+
+	/* volume_info->password freed at unmount */
+	if (volume_info->password) {
+		ses->password = kstrdup(volume_info->password, GFP_KERNEL);
+		if (!ses->password)
+			goto get_ses_fail;
+	}
+	if (volume_info->domainname) {
+		ses->domainName = kstrdup(volume_info->domainname, GFP_KERNEL);
+		if (!ses->domainName)
+			goto get_ses_fail;
+	}
+	if (volume_info->domainauto)
+		ses->domainAuto = volume_info->domainauto;
+	ses->cred_uid = volume_info->cred_uid;
+	ses->linux_uid = volume_info->linux_uid;
+
+	ses->sectype = volume_info->sectype;
+	ses->sign = volume_info->sign;
+
+	mutex_lock(&ses->session_mutex);
+	rc = cifs_negotiate_protocol(xid, ses);
+	if (!rc)
+		rc = cifs_setup_session(xid, ses, volume_info->local_nls);
+	mutex_unlock(&ses->session_mutex);
+	if (rc)
+		goto get_ses_fail;
+
+	/* success, put it on the list */
+	spin_lock(&cifs_tcp_ses_lock);
+	list_add(&ses->smb_ses_list, &server->smb_ses_list);
+	spin_unlock(&cifs_tcp_ses_lock);
+
+	free_xid(xid);
+
+	cifs_setup_ipc(ses, volume_info);
+
+	return ses;
+
+get_ses_fail:
+	sesInfoFree(ses);
+	free_xid(xid);
+	return ERR_PTR(rc);
+}
+
+static int match_tcon(struct cifs_tcon *tcon, struct smb_vol *volume_info)
+{
+	if (tcon->tidStatus == CifsExiting)
+		return 0;
+	if (strncmp(tcon->treeName, volume_info->UNC, MAX_TREE_SIZE))
+		return 0;
+	if (tcon->seal != volume_info->seal)
+		return 0;
+	if (tcon->snapshot_time != volume_info->snapshot_time)
+		return 0;
+	if (tcon->no_lease != volume_info->no_lease)
+		return 0;
+	return 1;
+}
+
+static struct cifs_tcon *
+cifs_find_tcon(struct cifs_ses *ses, struct smb_vol *volume_info)
+{
+	struct list_head *tmp;
+	struct cifs_tcon *tcon;
+
+	spin_lock(&cifs_tcp_ses_lock);
+	list_for_each(tmp, &ses->tcon_list) {
+		tcon = list_entry(tmp, struct cifs_tcon, tcon_list);
+		if (!match_tcon(tcon, volume_info))
+			continue;
+		++tcon->tc_count;
+		spin_unlock(&cifs_tcp_ses_lock);
+		return tcon;
+	}
+	spin_unlock(&cifs_tcp_ses_lock);
+	return NULL;
+}
+
+void
+cifs_put_tcon(struct cifs_tcon *tcon)
+{
+	unsigned int xid;
+	struct cifs_ses *ses;
+
+	/*
+	 * IPC tcon share the lifetime of their session and are
+	 * destroyed in the session put function
+	 */
+	if (tcon == NULL || tcon->ipc)
+		return;
+
+	ses = tcon->ses;
+	cifs_dbg(FYI, "%s: tc_count=%d\n", __func__, tcon->tc_count);
+	spin_lock(&cifs_tcp_ses_lock);
+	if (--tcon->tc_count > 0) {
+		spin_unlock(&cifs_tcp_ses_lock);
+		return;
+	}
+
+	list_del_init(&tcon->tcon_list);
+	spin_unlock(&cifs_tcp_ses_lock);
+
+	xid = get_xid();
+	if (ses->server->ops->tree_disconnect)
+		ses->server->ops->tree_disconnect(xid, tcon);
+	_free_xid(xid);
+
+	cifs_fscache_release_super_cookie(tcon);
+	tconInfoFree(tcon);
+	cifs_put_smb_ses(ses);
+}
+
+/**
+ * cifs_get_tcon - get a tcon matching @volume_info data from @ses
+ *
+ * - tcon refcount is the number of mount points using the tcon.
+ * - ses refcount is the number of tcon using the session.
+ *
+ * 1. This function assumes it is being called from cifs_mount() where
+ *    we already got a session reference (ses refcount +1).
+ *
+ * 2. Since we're in the context of adding a mount point, the end
+ *    result should be either:
+ *
+ * a) a new tcon already allocated with refcount=1 (1 mount point) and
+ *    its session refcount incremented (1 new tcon). This +1 was
+ *    already done in (1).
+ *
+ * b) an existing tcon with refcount+1 (add a mount point to it) and
+ *    identical ses refcount (no new tcon). Because of (1) we need to
+ *    decrement the ses refcount.
+ */
+static struct cifs_tcon *
+cifs_get_tcon(struct cifs_ses *ses, struct smb_vol *volume_info)
+{
+	int rc, xid;
+	struct cifs_tcon *tcon;
+
+	tcon = cifs_find_tcon(ses, volume_info);
+	if (tcon) {
+		/*
+		 * tcon has refcount already incremented but we need to
+		 * decrement extra ses reference gotten by caller (case b)
+		 */
+		cifs_dbg(FYI, "Found match on UNC path\n");
+		cifs_put_smb_ses(ses);
+		return tcon;
+	}
+
+	if (!ses->server->ops->tree_connect) {
+		rc = -ENOSYS;
+		goto out_fail;
+	}
+
+	tcon = tconInfoAlloc();
+	if (tcon == NULL) {
+		rc = -ENOMEM;
+		goto out_fail;
+	}
+
+	if (volume_info->snapshot_time) {
+		if (ses->server->vals->protocol_id == 0) {
+			cifs_dbg(VFS,
+			     "Use SMB2 or later for snapshot mount option\n");
+			rc = -EOPNOTSUPP;
+			goto out_fail;
+		} else
+			tcon->snapshot_time = volume_info->snapshot_time;
+	}
+
+	tcon->ses = ses;
+	if (volume_info->password) {
+		tcon->password = kstrdup(volume_info->password, GFP_KERNEL);
+		if (!tcon->password) {
+			rc = -ENOMEM;
+			goto out_fail;
+		}
+	}
+
+	if (volume_info->seal) {
+		if (ses->server->vals->protocol_id == 0) {
+			cifs_dbg(VFS,
+				 "SMB3 or later required for encryption\n");
+			rc = -EOPNOTSUPP;
+			goto out_fail;
+		} else if (tcon->ses->server->capabilities &
+					SMB2_GLOBAL_CAP_ENCRYPTION)
+			tcon->seal = true;
+		else {
+			cifs_dbg(VFS, "Encryption is not supported on share\n");
+			rc = -EOPNOTSUPP;
+			goto out_fail;
+		}
+	}
+
+	if (volume_info->linux_ext) {
+		if (ses->server->posix_ext_supported) {
+			tcon->posix_extensions = true;
+			printk_once(KERN_WARNING
+				"SMB3.11 POSIX Extensions are experimental\n");
+		} else {
+			cifs_dbg(VFS, "Server does not support mounting with posix SMB3.11 extensions.\n");
+			rc = -EOPNOTSUPP;
+			goto out_fail;
+		}
+	}
+
+	/*
+	 * BB Do we need to wrap session_mutex around this TCon call and Unix
+	 * SetFS as we do on SessSetup and reconnect?
+	 */
+	xid = get_xid();
+	rc = ses->server->ops->tree_connect(xid, ses, volume_info->UNC, tcon,
+					    volume_info->local_nls);
+	free_xid(xid);
+	cifs_dbg(FYI, "Tcon rc = %d\n", rc);
+	if (rc)
+		goto out_fail;
+
+	if (volume_info->nodfs) {
+		tcon->Flags &= ~SMB_SHARE_IS_IN_DFS;
+		cifs_dbg(FYI, "DFS disabled (%d)\n", tcon->Flags);
+	}
+	tcon->use_persistent = false;
+	/* check if SMB2 or later, CIFS does not support persistent handles */
+	if (volume_info->persistent) {
+		if (ses->server->vals->protocol_id == 0) {
+			cifs_dbg(VFS,
+			     "SMB3 or later required for persistent handles\n");
+			rc = -EOPNOTSUPP;
+			goto out_fail;
+		} else if (ses->server->capabilities &
+			   SMB2_GLOBAL_CAP_PERSISTENT_HANDLES)
+			tcon->use_persistent = true;
+		else /* persistent handles requested but not supported */ {
+			cifs_dbg(VFS,
+				"Persistent handles not supported on share\n");
+			rc = -EOPNOTSUPP;
+			goto out_fail;
+		}
+	} else if ((tcon->capabilities & SMB2_SHARE_CAP_CONTINUOUS_AVAILABILITY)
+	     && (ses->server->capabilities & SMB2_GLOBAL_CAP_PERSISTENT_HANDLES)
+	     && (volume_info->nopersistent == false)) {
+		cifs_dbg(FYI, "enabling persistent handles\n");
+		tcon->use_persistent = true;
+	} else if (volume_info->resilient) {
+		if (ses->server->vals->protocol_id == 0) {
+			cifs_dbg(VFS,
+			     "SMB2.1 or later required for resilient handles\n");
+			rc = -EOPNOTSUPP;
+			goto out_fail;
+		}
+		tcon->use_resilient = true;
+	}
+
+	/*
+	 * We can have only one retry value for a connection to a share so for
+	 * resources mounted more than once to the same server share the last
+	 * value passed in for the retry flag is used.
+	 */
+	tcon->retry = volume_info->retry;
+	tcon->nocase = volume_info->nocase;
+	tcon->nohandlecache = volume_info->nohandlecache;
+	tcon->local_lease = volume_info->local_lease;
+	tcon->no_lease = volume_info->no_lease;
+	INIT_LIST_HEAD(&tcon->pending_opens);
+
+	spin_lock(&cifs_tcp_ses_lock);
+	list_add(&tcon->tcon_list, &ses->tcon_list);
+	spin_unlock(&cifs_tcp_ses_lock);
+
+	cifs_fscache_get_super_cookie(tcon);
+
+	return tcon;
+
+out_fail:
+	tconInfoFree(tcon);
+	return ERR_PTR(rc);
+}
+
+void
+cifs_put_tlink(struct tcon_link *tlink)
+{
+	if (!tlink || IS_ERR(tlink))
+		return;
+
+	if (!atomic_dec_and_test(&tlink->tl_count) ||
+	    test_bit(TCON_LINK_IN_TREE, &tlink->tl_flags)) {
+		tlink->tl_time = jiffies;
+		return;
+	}
+
+	if (!IS_ERR(tlink_tcon(tlink)))
+		cifs_put_tcon(tlink_tcon(tlink));
+	kfree(tlink);
+	return;
+}
+
+static int
+compare_mount_options(struct super_block *sb, struct cifs_mnt_data *mnt_data)
+{
+	struct cifs_sb_info *old = CIFS_SB(sb);
+	struct cifs_sb_info *new = mnt_data->cifs_sb;
+	unsigned int oldflags = old->mnt_cifs_flags & CIFS_MOUNT_MASK;
+	unsigned int newflags = new->mnt_cifs_flags & CIFS_MOUNT_MASK;
+
+	if ((sb->s_flags & CIFS_MS_MASK) != (mnt_data->flags & CIFS_MS_MASK))
+		return 0;
+
+	if (old->mnt_cifs_serverino_autodisabled)
+		newflags &= ~CIFS_MOUNT_SERVER_INUM;
+
+	if (oldflags != newflags)
+		return 0;
+
+	/*
+	 * We want to share sb only if we don't specify an r/wsize or
+	 * specified r/wsize is greater than or equal to existing one.
+	 */
+	if (new->wsize && new->wsize < old->wsize)
+		return 0;
+
+	if (new->rsize && new->rsize < old->rsize)
+		return 0;
+
+	if (!uid_eq(old->mnt_uid, new->mnt_uid) || !gid_eq(old->mnt_gid, new->mnt_gid))
+		return 0;
+
+	if (old->mnt_file_mode != new->mnt_file_mode ||
+	    old->mnt_dir_mode != new->mnt_dir_mode)
+		return 0;
+
+	if (strcmp(old->local_nls->charset, new->local_nls->charset))
+		return 0;
+
+	if (old->actimeo != new->actimeo)
+		return 0;
+
+	return 1;
+}
+
+static int
+match_prepath(struct super_block *sb, struct cifs_mnt_data *mnt_data)
+{
+	struct cifs_sb_info *old = CIFS_SB(sb);
+	struct cifs_sb_info *new = mnt_data->cifs_sb;
+	bool old_set = (old->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH) &&
+		old->prepath;
+	bool new_set = (new->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH) &&
+		new->prepath;
+
+	if (old_set && new_set && !strcmp(new->prepath, old->prepath))
+		return 1;
+	else if (!old_set && !new_set)
+		return 1;
+
+	return 0;
+}
+
+int
+cifs_match_super(struct super_block *sb, void *data)
+{
+	struct cifs_mnt_data *mnt_data = (struct cifs_mnt_data *)data;
+	struct smb_vol *volume_info;
+	struct cifs_sb_info *cifs_sb;
+	struct TCP_Server_Info *tcp_srv;
+	struct cifs_ses *ses;
+	struct cifs_tcon *tcon;
+	struct tcon_link *tlink;
+	int rc = 0;
+
+	spin_lock(&cifs_tcp_ses_lock);
+	cifs_sb = CIFS_SB(sb);
+	tlink = cifs_get_tlink(cifs_sb_master_tlink(cifs_sb));
+	if (tlink == NULL) {
+		/* can not match superblock if tlink were ever null */
+		spin_unlock(&cifs_tcp_ses_lock);
+		return 0;
+	}
+	tcon = tlink_tcon(tlink);
+	ses = tcon->ses;
+	tcp_srv = ses->server;
+
+	volume_info = mnt_data->vol;
+
+	if (!match_server(tcp_srv, volume_info) ||
+	    !match_session(ses, volume_info) ||
+	    !match_tcon(tcon, volume_info) ||
+	    !match_prepath(sb, mnt_data)) {
+		rc = 0;
+		goto out;
+	}
+
+	rc = compare_mount_options(sb, mnt_data);
+out:
+	spin_unlock(&cifs_tcp_ses_lock);
+	cifs_put_tlink(tlink);
+	return rc;
+}
+
+int
+get_dfs_path(const unsigned int xid, struct cifs_ses *ses, const char *old_path,
+	     const struct nls_table *nls_codepage, unsigned int *num_referrals,
+	     struct dfs_info3_param **referrals, int remap)
+{
+	int rc = 0;
+
+	if (!ses->server->ops->get_dfs_refer)
+		return -ENOSYS;
+
+	*num_referrals = 0;
+	*referrals = NULL;
+
+	rc = ses->server->ops->get_dfs_refer(xid, ses, old_path,
+					     referrals, num_referrals,
+					     nls_codepage, remap);
+	return rc;
+}
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+static struct lock_class_key cifs_key[2];
+static struct lock_class_key cifs_slock_key[2];
+
+static inline void
+cifs_reclassify_socket4(struct socket *sock)
+{
+	struct sock *sk = sock->sk;
+	BUG_ON(!sock_allow_reclassification(sk));
+	sock_lock_init_class_and_name(sk, "slock-AF_INET-CIFS",
+		&cifs_slock_key[0], "sk_lock-AF_INET-CIFS", &cifs_key[0]);
+}
+
+static inline void
+cifs_reclassify_socket6(struct socket *sock)
+{
+	struct sock *sk = sock->sk;
+	BUG_ON(!sock_allow_reclassification(sk));
+	sock_lock_init_class_and_name(sk, "slock-AF_INET6-CIFS",
+		&cifs_slock_key[1], "sk_lock-AF_INET6-CIFS", &cifs_key[1]);
+}
+#else
+static inline void
+cifs_reclassify_socket4(struct socket *sock)
+{
+}
+
+static inline void
+cifs_reclassify_socket6(struct socket *sock)
+{
+}
+#endif
+
+/* See RFC1001 section 14 on representation of Netbios names */
+static void rfc1002mangle(char *target, char *source, unsigned int length)
+{
+	unsigned int i, j;
+
+	for (i = 0, j = 0; i < (length); i++) {
+		/* mask a nibble at a time and encode */
+		target[j] = 'A' + (0x0F & (source[i] >> 4));
+		target[j+1] = 'A' + (0x0F & source[i]);
+		j += 2;
+	}
+
+}
+
+static int
+bind_socket(struct TCP_Server_Info *server)
+{
+	int rc = 0;
+	if (server->srcaddr.ss_family != AF_UNSPEC) {
+		/* Bind to the specified local IP address */
+		struct socket *socket = server->ssocket;
+		rc = socket->ops->bind(socket,
+				       (struct sockaddr *) &server->srcaddr,
+				       sizeof(server->srcaddr));
+		if (rc < 0) {
+			struct sockaddr_in *saddr4;
+			struct sockaddr_in6 *saddr6;
+			saddr4 = (struct sockaddr_in *)&server->srcaddr;
+			saddr6 = (struct sockaddr_in6 *)&server->srcaddr;
+			if (saddr6->sin6_family == AF_INET6)
+				cifs_dbg(VFS, "Failed to bind to: %pI6c, error: %d\n",
+					 &saddr6->sin6_addr, rc);
+			else
+				cifs_dbg(VFS, "Failed to bind to: %pI4, error: %d\n",
+					 &saddr4->sin_addr.s_addr, rc);
+		}
+	}
+	return rc;
+}
+
+static int
+ip_rfc1001_connect(struct TCP_Server_Info *server)
+{
+	int rc = 0;
+	/*
+	 * some servers require RFC1001 sessinit before sending
+	 * negprot - BB check reconnection in case where second
+	 * sessinit is sent but no second negprot
+	 */
+	struct rfc1002_session_packet *ses_init_buf;
+	struct smb_hdr *smb_buf;
+	ses_init_buf = kzalloc(sizeof(struct rfc1002_session_packet),
+			       GFP_KERNEL);
+	if (ses_init_buf) {
+		ses_init_buf->trailer.session_req.called_len = 32;
+
+		if (server->server_RFC1001_name[0] != 0)
+			rfc1002mangle(ses_init_buf->trailer.
+				      session_req.called_name,
+				      server->server_RFC1001_name,
+				      RFC1001_NAME_LEN_WITH_NULL);
+		else
+			rfc1002mangle(ses_init_buf->trailer.
+				      session_req.called_name,
+				      DEFAULT_CIFS_CALLED_NAME,
+				      RFC1001_NAME_LEN_WITH_NULL);
+
+		ses_init_buf->trailer.session_req.calling_len = 32;
+
+		/*
+		 * calling name ends in null (byte 16) from old smb
+		 * convention.
+		 */
+		if (server->workstation_RFC1001_name[0] != 0)
+			rfc1002mangle(ses_init_buf->trailer.
+				      session_req.calling_name,
+				      server->workstation_RFC1001_name,
+				      RFC1001_NAME_LEN_WITH_NULL);
+		else
+			rfc1002mangle(ses_init_buf->trailer.
+				      session_req.calling_name,
+				      "LINUX_CIFS_CLNT",
+				      RFC1001_NAME_LEN_WITH_NULL);
+
+		ses_init_buf->trailer.session_req.scope1 = 0;
+		ses_init_buf->trailer.session_req.scope2 = 0;
+		smb_buf = (struct smb_hdr *)ses_init_buf;
+
+		/* sizeof RFC1002_SESSION_REQUEST with no scope */
+		smb_buf->smb_buf_length = cpu_to_be32(0x81000044);
+		rc = smb_send(server, smb_buf, 0x44);
+		kfree(ses_init_buf);
+		/*
+		 * RFC1001 layer in at least one server
+		 * requires very short break before negprot
+		 * presumably because not expecting negprot
+		 * to follow so fast.  This is a simple
+		 * solution that works without
+		 * complicating the code and causes no
+		 * significant slowing down on mount
+		 * for everyone else
+		 */
+		usleep_range(1000, 2000);
+	}
+	/*
+	 * else the negprot may still work without this
+	 * even though malloc failed
+	 */
+
+	return rc;
+}
+
+static int
+generic_ip_connect(struct TCP_Server_Info *server)
+{
+	int rc = 0;
+	__be16 sport;
+	int slen, sfamily;
+	struct socket *socket = server->ssocket;
+	struct sockaddr *saddr;
+
+	saddr = (struct sockaddr *) &server->dstaddr;
+
+	if (server->dstaddr.ss_family == AF_INET6) {
+		sport = ((struct sockaddr_in6 *) saddr)->sin6_port;
+		slen = sizeof(struct sockaddr_in6);
+		sfamily = AF_INET6;
+	} else {
+		sport = ((struct sockaddr_in *) saddr)->sin_port;
+		slen = sizeof(struct sockaddr_in);
+		sfamily = AF_INET;
+	}
+
+	if (socket == NULL) {
+		rc = __sock_create(cifs_net_ns(server), sfamily, SOCK_STREAM,
+				   IPPROTO_TCP, &socket, 1);
+		if (rc < 0) {
+			cifs_dbg(VFS, "Error %d creating socket\n", rc);
+			server->ssocket = NULL;
+			return rc;
+		}
+
+		/* BB other socket options to set KEEPALIVE, NODELAY? */
+		cifs_dbg(FYI, "Socket created\n");
+		server->ssocket = socket;
+		socket->sk->sk_allocation = GFP_NOFS;
+		if (sfamily == AF_INET6)
+			cifs_reclassify_socket6(socket);
+		else
+			cifs_reclassify_socket4(socket);
+	}
+
+	rc = bind_socket(server);
+	if (rc < 0)
+		return rc;
+
+	/*
+	 * Eventually check for other socket options to change from
+	 * the default. sock_setsockopt not used because it expects
+	 * user space buffer
+	 */
+	socket->sk->sk_rcvtimeo = 7 * HZ;
+	socket->sk->sk_sndtimeo = 5 * HZ;
+
+	/* make the bufsizes depend on wsize/rsize and max requests */
+	if (server->noautotune) {
+		if (socket->sk->sk_sndbuf < (200 * 1024))
+			socket->sk->sk_sndbuf = 200 * 1024;
+		if (socket->sk->sk_rcvbuf < (140 * 1024))
+			socket->sk->sk_rcvbuf = 140 * 1024;
+	}
+
+	if (server->tcp_nodelay) {
+		int val = 1;
+		rc = kernel_setsockopt(socket, SOL_TCP, TCP_NODELAY,
+				(char *)&val, sizeof(val));
+		if (rc)
+			cifs_dbg(FYI, "set TCP_NODELAY socket option error %d\n",
+				 rc);
+	}
+
+	cifs_dbg(FYI, "sndbuf %d rcvbuf %d rcvtimeo 0x%lx\n",
+		 socket->sk->sk_sndbuf,
+		 socket->sk->sk_rcvbuf, socket->sk->sk_rcvtimeo);
+
+	rc = socket->ops->connect(socket, saddr, slen, 0);
+	if (rc < 0) {
+		cifs_dbg(FYI, "Error %d connecting to server\n", rc);
+		sock_release(socket);
+		server->ssocket = NULL;
+		return rc;
+	}
+
+	if (sport == htons(RFC1001_PORT))
+		rc = ip_rfc1001_connect(server);
+
+	return rc;
+}
+
+static int
+ip_connect(struct TCP_Server_Info *server)
+{
+	__be16 *sport;
+	struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)&server->dstaddr;
+	struct sockaddr_in *addr = (struct sockaddr_in *)&server->dstaddr;
+
+	if (server->dstaddr.ss_family == AF_INET6)
+		sport = &addr6->sin6_port;
+	else
+		sport = &addr->sin_port;
+
+	if (*sport == 0) {
+		int rc;
+
+		/* try with 445 port at first */
+		*sport = htons(CIFS_PORT);
+
+		rc = generic_ip_connect(server);
+		if (rc >= 0)
+			return rc;
+
+		/* if it failed, try with 139 port */
+		*sport = htons(RFC1001_PORT);
+	}
+
+	return generic_ip_connect(server);
+}
+
+void reset_cifs_unix_caps(unsigned int xid, struct cifs_tcon *tcon,
+			  struct cifs_sb_info *cifs_sb, struct smb_vol *vol_info)
+{
+	/* if we are reconnecting then should we check to see if
+	 * any requested capabilities changed locally e.g. via
+	 * remount but we can not do much about it here
+	 * if they have (even if we could detect it by the following)
+	 * Perhaps we could add a backpointer to array of sb from tcon
+	 * or if we change to make all sb to same share the same
+	 * sb as NFS - then we only have one backpointer to sb.
+	 * What if we wanted to mount the server share twice once with
+	 * and once without posixacls or posix paths? */
+	__u64 saved_cap = le64_to_cpu(tcon->fsUnixInfo.Capability);
+
+	if (vol_info && vol_info->no_linux_ext) {
+		tcon->fsUnixInfo.Capability = 0;
+		tcon->unix_ext = 0; /* Unix Extensions disabled */
+		cifs_dbg(FYI, "Linux protocol extensions disabled\n");
+		return;
+	} else if (vol_info)
+		tcon->unix_ext = 1; /* Unix Extensions supported */
+
+	if (tcon->unix_ext == 0) {
+		cifs_dbg(FYI, "Unix extensions disabled so not set on reconnect\n");
+		return;
+	}
+
+	if (!CIFSSMBQFSUnixInfo(xid, tcon)) {
+		__u64 cap = le64_to_cpu(tcon->fsUnixInfo.Capability);
+		cifs_dbg(FYI, "unix caps which server supports %lld\n", cap);
+		/* check for reconnect case in which we do not
+		   want to change the mount behavior if we can avoid it */
+		if (vol_info == NULL) {
+			/* turn off POSIX ACL and PATHNAMES if not set
+			   originally at mount time */
+			if ((saved_cap & CIFS_UNIX_POSIX_ACL_CAP) == 0)
+				cap &= ~CIFS_UNIX_POSIX_ACL_CAP;
+			if ((saved_cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) == 0) {
+				if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP)
+					cifs_dbg(VFS, "POSIXPATH support change\n");
+				cap &= ~CIFS_UNIX_POSIX_PATHNAMES_CAP;
+			} else if ((cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) == 0) {
+				cifs_dbg(VFS, "possible reconnect error\n");
+				cifs_dbg(VFS, "server disabled POSIX path support\n");
+			}
+		}
+
+		if (cap & CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP)
+			cifs_dbg(VFS, "per-share encryption not supported yet\n");
+
+		cap &= CIFS_UNIX_CAP_MASK;
+		if (vol_info && vol_info->no_psx_acl)
+			cap &= ~CIFS_UNIX_POSIX_ACL_CAP;
+		else if (CIFS_UNIX_POSIX_ACL_CAP & cap) {
+			cifs_dbg(FYI, "negotiated posix acl support\n");
+			if (cifs_sb)
+				cifs_sb->mnt_cifs_flags |=
+					CIFS_MOUNT_POSIXACL;
+		}
+
+		if (vol_info && vol_info->posix_paths == 0)
+			cap &= ~CIFS_UNIX_POSIX_PATHNAMES_CAP;
+		else if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) {
+			cifs_dbg(FYI, "negotiate posix pathnames\n");
+			if (cifs_sb)
+				cifs_sb->mnt_cifs_flags |=
+					CIFS_MOUNT_POSIX_PATHS;
+		}
+
+		cifs_dbg(FYI, "Negotiate caps 0x%x\n", (int)cap);
+#ifdef CONFIG_CIFS_DEBUG2
+		if (cap & CIFS_UNIX_FCNTL_CAP)
+			cifs_dbg(FYI, "FCNTL cap\n");
+		if (cap & CIFS_UNIX_EXTATTR_CAP)
+			cifs_dbg(FYI, "EXTATTR cap\n");
+		if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP)
+			cifs_dbg(FYI, "POSIX path cap\n");
+		if (cap & CIFS_UNIX_XATTR_CAP)
+			cifs_dbg(FYI, "XATTR cap\n");
+		if (cap & CIFS_UNIX_POSIX_ACL_CAP)
+			cifs_dbg(FYI, "POSIX ACL cap\n");
+		if (cap & CIFS_UNIX_LARGE_READ_CAP)
+			cifs_dbg(FYI, "very large read cap\n");
+		if (cap & CIFS_UNIX_LARGE_WRITE_CAP)
+			cifs_dbg(FYI, "very large write cap\n");
+		if (cap & CIFS_UNIX_TRANSPORT_ENCRYPTION_CAP)
+			cifs_dbg(FYI, "transport encryption cap\n");
+		if (cap & CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP)
+			cifs_dbg(FYI, "mandatory transport encryption cap\n");
+#endif /* CIFS_DEBUG2 */
+		if (CIFSSMBSetFSUnixInfo(xid, tcon, cap)) {
+			if (vol_info == NULL) {
+				cifs_dbg(FYI, "resetting capabilities failed\n");
+			} else
+				cifs_dbg(VFS, "Negotiating Unix capabilities with the server failed. Consider mounting with the Unix Extensions disabled if problems are found by specifying the nounix mount option.\n");
+
+		}
+	}
+}
+
+int cifs_setup_cifs_sb(struct smb_vol *pvolume_info,
+			struct cifs_sb_info *cifs_sb)
+{
+	INIT_DELAYED_WORK(&cifs_sb->prune_tlinks, cifs_prune_tlinks);
+
+	spin_lock_init(&cifs_sb->tlink_tree_lock);
+	cifs_sb->tlink_tree = RB_ROOT;
+
+	/*
+	 * Temporarily set r/wsize for matching superblock. If we end up using
+	 * new sb then client will later negotiate it downward if needed.
+	 */
+	cifs_sb->rsize = pvolume_info->rsize;
+	cifs_sb->wsize = pvolume_info->wsize;
+
+	cifs_sb->mnt_uid = pvolume_info->linux_uid;
+	cifs_sb->mnt_gid = pvolume_info->linux_gid;
+	cifs_sb->mnt_file_mode = pvolume_info->file_mode;
+	cifs_sb->mnt_dir_mode = pvolume_info->dir_mode;
+	cifs_dbg(FYI, "file mode: %04ho  dir mode: %04ho\n",
+		 cifs_sb->mnt_file_mode, cifs_sb->mnt_dir_mode);
+
+	cifs_sb->actimeo = pvolume_info->actimeo;
+	cifs_sb->local_nls = pvolume_info->local_nls;
+
+	if (pvolume_info->noperm)
+		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_NO_PERM;
+	if (pvolume_info->setuids)
+		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_SET_UID;
+	if (pvolume_info->setuidfromacl)
+		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_UID_FROM_ACL;
+	if (pvolume_info->server_ino)
+		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_SERVER_INUM;
+	if (pvolume_info->remap)
+		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_MAP_SFM_CHR;
+	if (pvolume_info->sfu_remap)
+		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_MAP_SPECIAL_CHR;
+	if (pvolume_info->no_xattr)
+		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_NO_XATTR;
+	if (pvolume_info->sfu_emul)
+		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_UNX_EMUL;
+	if (pvolume_info->nobrl)
+		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_NO_BRL;
+	if (pvolume_info->nohandlecache)
+		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_NO_HANDLE_CACHE;
+	if (pvolume_info->nostrictsync)
+		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_NOSSYNC;
+	if (pvolume_info->mand_lock)
+		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_NOPOSIXBRL;
+	if (pvolume_info->rwpidforward)
+		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_RWPIDFORWARD;
+	if (pvolume_info->cifs_acl)
+		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_CIFS_ACL;
+	if (pvolume_info->backupuid_specified) {
+		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_CIFS_BACKUPUID;
+		cifs_sb->mnt_backupuid = pvolume_info->backupuid;
+	}
+	if (pvolume_info->backupgid_specified) {
+		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_CIFS_BACKUPGID;
+		cifs_sb->mnt_backupgid = pvolume_info->backupgid;
+	}
+	if (pvolume_info->override_uid)
+		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_OVERR_UID;
+	if (pvolume_info->override_gid)
+		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_OVERR_GID;
+	if (pvolume_info->dynperm)
+		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_DYNPERM;
+	if (pvolume_info->fsc)
+		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_FSCACHE;
+	if (pvolume_info->multiuser)
+		cifs_sb->mnt_cifs_flags |= (CIFS_MOUNT_MULTIUSER |
+					    CIFS_MOUNT_NO_PERM);
+	if (pvolume_info->strict_io)
+		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_STRICT_IO;
+	if (pvolume_info->direct_io) {
+		cifs_dbg(FYI, "mounting share using direct i/o\n");
+		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_DIRECT_IO;
+	}
+	if (pvolume_info->mfsymlinks) {
+		if (pvolume_info->sfu_emul) {
+			/*
+			 * Our SFU ("Services for Unix" emulation does not allow
+			 * creating symlinks but does allow reading existing SFU
+			 * symlinks (it does allow both creating and reading SFU
+			 * style mknod and FIFOs though). When "mfsymlinks" and
+			 * "sfu" are both enabled at the same time, it allows
+			 * reading both types of symlinks, but will only create
+			 * them with mfsymlinks format. This allows better
+			 * Apple compatibility (probably better for Samba too)
+			 * while still recognizing old Windows style symlinks.
+			 */
+			cifs_dbg(VFS, "mount options mfsymlinks and sfu both enabled\n");
+		}
+		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_MF_SYMLINKS;
+	}
+
+	if ((pvolume_info->cifs_acl) && (pvolume_info->dynperm))
+		cifs_dbg(VFS, "mount option dynperm ignored if cifsacl mount option supported\n");
+
+	if (pvolume_info->prepath) {
+		cifs_sb->prepath = kstrdup(pvolume_info->prepath, GFP_KERNEL);
+		if (cifs_sb->prepath == NULL)
+			return -ENOMEM;
+	}
+
+	return 0;
+}
+
+static void
+cleanup_volume_info_contents(struct smb_vol *volume_info)
+{
+	kfree(volume_info->username);
+	kzfree(volume_info->password);
+	kfree(volume_info->UNC);
+	kfree(volume_info->domainname);
+	kfree(volume_info->iocharset);
+	kfree(volume_info->prepath);
+}
+
+void
+cifs_cleanup_volume_info(struct smb_vol *volume_info)
+{
+	if (!volume_info)
+		return;
+	cleanup_volume_info_contents(volume_info);
+	kfree(volume_info);
+}
+
+
+#ifdef CONFIG_CIFS_DFS_UPCALL
+/*
+ * cifs_build_path_to_root returns full path to root when we do not have an
+ * exiting connection (tcon)
+ */
+static char *
+build_unc_path_to_root(const struct smb_vol *vol,
+		const struct cifs_sb_info *cifs_sb)
+{
+	char *full_path, *pos;
+	unsigned int pplen = vol->prepath ? strlen(vol->prepath) + 1 : 0;
+	unsigned int unc_len = strnlen(vol->UNC, MAX_TREE_SIZE + 1);
+
+	full_path = kmalloc(unc_len + pplen + 1, GFP_KERNEL);
+	if (full_path == NULL)
+		return ERR_PTR(-ENOMEM);
+
+	strncpy(full_path, vol->UNC, unc_len);
+	pos = full_path + unc_len;
+
+	if (pplen) {
+		*pos = CIFS_DIR_SEP(cifs_sb);
+		strncpy(pos + 1, vol->prepath, pplen);
+		pos += pplen;
+	}
+
+	*pos = '\0'; /* add trailing null */
+	convert_delimiter(full_path, CIFS_DIR_SEP(cifs_sb));
+	cifs_dbg(FYI, "%s: full_path=%s\n", __func__, full_path);
+	return full_path;
+}
+
+/*
+ * Perform a dfs referral query for a share and (optionally) prefix
+ *
+ * If a referral is found, cifs_sb->mountdata will be (re-)allocated
+ * to a string containing updated options for the submount.  Otherwise it
+ * will be left untouched.
+ *
+ * Returns the rc from get_dfs_path to the caller, which can be used to
+ * determine whether there were referrals.
+ */
+static int
+expand_dfs_referral(const unsigned int xid, struct cifs_ses *ses,
+		    struct smb_vol *volume_info, struct cifs_sb_info *cifs_sb,
+		    int check_prefix)
+{
+	int rc;
+	unsigned int num_referrals = 0;
+	struct dfs_info3_param *referrals = NULL;
+	char *full_path = NULL, *ref_path = NULL, *mdata = NULL;
+
+	full_path = build_unc_path_to_root(volume_info, cifs_sb);
+	if (IS_ERR(full_path))
+		return PTR_ERR(full_path);
+
+	/* For DFS paths, skip the first '\' of the UNC */
+	ref_path = check_prefix ? full_path + 1 : volume_info->UNC + 1;
+
+	rc = get_dfs_path(xid, ses, ref_path, cifs_sb->local_nls,
+			  &num_referrals, &referrals, cifs_remap(cifs_sb));
+
+	if (!rc && num_referrals > 0) {
+		char *fake_devname = NULL;
+
+		mdata = cifs_compose_mount_options(cifs_sb->mountdata,
+						   full_path + 1, referrals,
+						   &fake_devname);
+
+		free_dfs_info_array(referrals, num_referrals);
+
+		if (IS_ERR(mdata)) {
+			rc = PTR_ERR(mdata);
+			mdata = NULL;
+		} else {
+			cleanup_volume_info_contents(volume_info);
+			rc = cifs_setup_volume_info(volume_info, mdata,
+							fake_devname, false);
+		}
+		kfree(fake_devname);
+		kfree(cifs_sb->mountdata);
+		cifs_sb->mountdata = mdata;
+	}
+	kfree(full_path);
+	return rc;
+}
+#endif
+
+static int
+cifs_setup_volume_info(struct smb_vol *volume_info, char *mount_data,
+			const char *devname, bool is_smb3)
+{
+	int rc = 0;
+
+	if (cifs_parse_mount_options(mount_data, devname, volume_info, is_smb3))
+		return -EINVAL;
+
+	if (volume_info->nullauth) {
+		cifs_dbg(FYI, "Anonymous login\n");
+		kfree(volume_info->username);
+		volume_info->username = NULL;
+	} else if (volume_info->username) {
+		/* BB fixme parse for domain name here */
+		cifs_dbg(FYI, "Username: %s\n", volume_info->username);
+	} else {
+		cifs_dbg(VFS, "No username specified\n");
+	/* In userspace mount helper we can get user name from alternate
+	   locations such as env variables and files on disk */
+		return -EINVAL;
+	}
+
+	/* this is needed for ASCII cp to Unicode converts */
+	if (volume_info->iocharset == NULL) {
+		/* load_nls_default cannot return null */
+		volume_info->local_nls = load_nls_default();
+	} else {
+		volume_info->local_nls = load_nls(volume_info->iocharset);
+		if (volume_info->local_nls == NULL) {
+			cifs_dbg(VFS, "CIFS mount error: iocharset %s not found\n",
+				 volume_info->iocharset);
+			return -ELIBACC;
+		}
+	}
+
+	return rc;
+}
+
+struct smb_vol *
+cifs_get_volume_info(char *mount_data, const char *devname, bool is_smb3)
+{
+	int rc;
+	struct smb_vol *volume_info;
+
+	volume_info = kmalloc(sizeof(struct smb_vol), GFP_KERNEL);
+	if (!volume_info)
+		return ERR_PTR(-ENOMEM);
+
+	rc = cifs_setup_volume_info(volume_info, mount_data, devname, is_smb3);
+	if (rc) {
+		cifs_cleanup_volume_info(volume_info);
+		volume_info = ERR_PTR(rc);
+	}
+
+	return volume_info;
+}
+
+static int
+cifs_are_all_path_components_accessible(struct TCP_Server_Info *server,
+					unsigned int xid,
+					struct cifs_tcon *tcon,
+					struct cifs_sb_info *cifs_sb,
+					char *full_path)
+{
+	int rc;
+	char *s;
+	char sep, tmp;
+
+	sep = CIFS_DIR_SEP(cifs_sb);
+	s = full_path;
+
+	rc = server->ops->is_path_accessible(xid, tcon, cifs_sb, "");
+	while (rc == 0) {
+		/* skip separators */
+		while (*s == sep)
+			s++;
+		if (!*s)
+			break;
+		/* next separator */
+		while (*s && *s != sep)
+			s++;
+
+		/*
+		 * temporarily null-terminate the path at the end of
+		 * the current component
+		 */
+		tmp = *s;
+		*s = 0;
+		rc = server->ops->is_path_accessible(xid, tcon, cifs_sb,
+						     full_path);
+		*s = tmp;
+	}
+	return rc;
+}
+
+int
+cifs_mount(struct cifs_sb_info *cifs_sb, struct smb_vol *volume_info)
+{
+	int rc;
+	unsigned int xid;
+	struct cifs_ses *ses;
+	struct cifs_tcon *tcon;
+	struct TCP_Server_Info *server;
+	char   *full_path;
+	struct tcon_link *tlink;
+#ifdef CONFIG_CIFS_DFS_UPCALL
+	int referral_walks_count = 0;
+#endif
+
+#ifdef CONFIG_CIFS_DFS_UPCALL
+try_mount_again:
+	/* cleanup activities if we're chasing a referral */
+	if (referral_walks_count) {
+		if (tcon)
+			cifs_put_tcon(tcon);
+		else if (ses)
+			cifs_put_smb_ses(ses);
+
+		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_POSIX_PATHS;
+
+		free_xid(xid);
+	}
+#endif
+	rc = 0;
+	tcon = NULL;
+	ses = NULL;
+	server = NULL;
+	full_path = NULL;
+	tlink = NULL;
+
+	xid = get_xid();
+
+	/* get a reference to a tcp session */
+	server = cifs_get_tcp_session(volume_info);
+	if (IS_ERR(server)) {
+		rc = PTR_ERR(server);
+		goto out;
+	}
+	if ((volume_info->max_credits < 20) ||
+	     (volume_info->max_credits > 60000))
+		server->max_credits = SMB2_MAX_CREDITS_AVAILABLE;
+	else
+		server->max_credits = volume_info->max_credits;
+	/* get a reference to a SMB session */
+	ses = cifs_get_smb_ses(server, volume_info);
+	if (IS_ERR(ses)) {
+		rc = PTR_ERR(ses);
+		ses = NULL;
+		goto mount_fail_check;
+	}
+
+	if ((volume_info->persistent == true) && ((ses->server->capabilities &
+		SMB2_GLOBAL_CAP_PERSISTENT_HANDLES) == 0)) {
+		cifs_dbg(VFS, "persistent handles not supported by server\n");
+		rc = -EOPNOTSUPP;
+		goto mount_fail_check;
+	}
+
+	/* search for existing tcon to this server share */
+	tcon = cifs_get_tcon(ses, volume_info);
+	if (IS_ERR(tcon)) {
+		rc = PTR_ERR(tcon);
+		tcon = NULL;
+		if (rc == -EACCES)
+			goto mount_fail_check;
+
+		goto remote_path_check;
+	}
+
+	/* if new SMB3.11 POSIX extensions are supported do not remap / and \ */
+	if (tcon->posix_extensions)
+		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_POSIX_PATHS;
+
+	/* tell server which Unix caps we support */
+	if (cap_unix(tcon->ses)) {
+		/* reset of caps checks mount to see if unix extensions
+		   disabled for just this mount */
+		reset_cifs_unix_caps(xid, tcon, cifs_sb, volume_info);
+		if ((tcon->ses->server->tcpStatus == CifsNeedReconnect) &&
+		    (le64_to_cpu(tcon->fsUnixInfo.Capability) &
+		     CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP)) {
+			rc = -EACCES;
+			goto mount_fail_check;
+		}
+	} else
+		tcon->unix_ext = 0; /* server does not support them */
+
+	/* do not care if a following call succeed - informational */
+	if (!tcon->pipe && server->ops->qfs_tcon)
+		server->ops->qfs_tcon(xid, tcon);
+
+	cifs_sb->wsize = server->ops->negotiate_wsize(tcon, volume_info);
+	cifs_sb->rsize = server->ops->negotiate_rsize(tcon, volume_info);
+
+remote_path_check:
+#ifdef CONFIG_CIFS_DFS_UPCALL
+	/*
+	 * Perform an unconditional check for whether there are DFS
+	 * referrals for this path without prefix, to provide support
+	 * for DFS referrals from w2k8 servers which don't seem to respond
+	 * with PATH_NOT_COVERED to requests that include the prefix.
+	 * Chase the referral if found, otherwise continue normally.
+	 */
+	if (referral_walks_count == 0) {
+		int refrc = expand_dfs_referral(xid, ses, volume_info, cifs_sb,
+						false);
+		if (!refrc) {
+			referral_walks_count++;
+			goto try_mount_again;
+		}
+	}
+#endif
+
+	/* check if a whole path is not remote */
+	if (!rc && tcon) {
+		if (!server->ops->is_path_accessible) {
+			rc = -ENOSYS;
+			goto mount_fail_check;
+		}
+		/*
+		 * cifs_build_path_to_root works only when we have a valid tcon
+		 */
+		full_path = cifs_build_path_to_root(volume_info, cifs_sb, tcon,
+					tcon->Flags & SMB_SHARE_IS_IN_DFS);
+		if (full_path == NULL) {
+			rc = -ENOMEM;
+			goto mount_fail_check;
+		}
+		rc = server->ops->is_path_accessible(xid, tcon, cifs_sb,
+						     full_path);
+		if (rc != 0 && rc != -EREMOTE) {
+			kfree(full_path);
+			goto mount_fail_check;
+		}
+
+		if (rc != -EREMOTE) {
+			rc = cifs_are_all_path_components_accessible(server,
+							     xid, tcon, cifs_sb,
+							     full_path);
+			if (rc != 0) {
+				cifs_dbg(VFS, "cannot query dirs between root and final path, "
+					 "enabling CIFS_MOUNT_USE_PREFIX_PATH\n");
+				cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH;
+				rc = 0;
+			}
+		}
+		kfree(full_path);
+	}
+
+	/* get referral if needed */
+	if (rc == -EREMOTE) {
+#ifdef CONFIG_CIFS_DFS_UPCALL
+		if (referral_walks_count > MAX_NESTED_LINKS) {
+			/*
+			 * BB: when we implement proper loop detection,
+			 *     we will remove this check. But now we need it
+			 *     to prevent an indefinite loop if 'DFS tree' is
+			 *     misconfigured (i.e. has loops).
+			 */
+			rc = -ELOOP;
+			goto mount_fail_check;
+		}
+
+		rc = expand_dfs_referral(xid, ses, volume_info, cifs_sb, true);
+
+		if (!rc) {
+			referral_walks_count++;
+			goto try_mount_again;
+		}
+		goto mount_fail_check;
+#else /* No DFS support, return error on mount */
+		rc = -EOPNOTSUPP;
+#endif
+	}
+
+	if (rc)
+		goto mount_fail_check;
+
+	/* now, hang the tcon off of the superblock */
+	tlink = kzalloc(sizeof *tlink, GFP_KERNEL);
+	if (tlink == NULL) {
+		rc = -ENOMEM;
+		goto mount_fail_check;
+	}
+
+	tlink->tl_uid = ses->linux_uid;
+	tlink->tl_tcon = tcon;
+	tlink->tl_time = jiffies;
+	set_bit(TCON_LINK_MASTER, &tlink->tl_flags);
+	set_bit(TCON_LINK_IN_TREE, &tlink->tl_flags);
+
+	cifs_sb->master_tlink = tlink;
+	spin_lock(&cifs_sb->tlink_tree_lock);
+	tlink_rb_insert(&cifs_sb->tlink_tree, tlink);
+	spin_unlock(&cifs_sb->tlink_tree_lock);
+
+	queue_delayed_work(cifsiod_wq, &cifs_sb->prune_tlinks,
+				TLINK_IDLE_EXPIRE);
+
+mount_fail_check:
+	/* on error free sesinfo and tcon struct if needed */
+	if (rc) {
+		/* If find_unc succeeded then rc == 0 so we can not end */
+		/* up accidentally freeing someone elses tcon struct */
+		if (tcon)
+			cifs_put_tcon(tcon);
+		else if (ses)
+			cifs_put_smb_ses(ses);
+		else
+			cifs_put_tcp_session(server, 0);
+	}
+
+out:
+	free_xid(xid);
+	return rc;
+}
+
+/*
+ * Issue a TREE_CONNECT request.
+ */
+int
+CIFSTCon(const unsigned int xid, struct cifs_ses *ses,
+	 const char *tree, struct cifs_tcon *tcon,
+	 const struct nls_table *nls_codepage)
+{
+	struct smb_hdr *smb_buffer;
+	struct smb_hdr *smb_buffer_response;
+	TCONX_REQ *pSMB;
+	TCONX_RSP *pSMBr;
+	unsigned char *bcc_ptr;
+	int rc = 0;
+	int length;
+	__u16 bytes_left, count;
+
+	if (ses == NULL)
+		return -EIO;
+
+	smb_buffer = cifs_buf_get();
+	if (smb_buffer == NULL)
+		return -ENOMEM;
+
+	smb_buffer_response = smb_buffer;
+
+	header_assemble(smb_buffer, SMB_COM_TREE_CONNECT_ANDX,
+			NULL /*no tid */ , 4 /*wct */ );
+
+	smb_buffer->Mid = get_next_mid(ses->server);
+	smb_buffer->Uid = ses->Suid;
+	pSMB = (TCONX_REQ *) smb_buffer;
+	pSMBr = (TCONX_RSP *) smb_buffer_response;
+
+	pSMB->AndXCommand = 0xFF;
+	pSMB->Flags = cpu_to_le16(TCON_EXTENDED_SECINFO);
+	bcc_ptr = &pSMB->Password[0];
+	if (tcon->pipe || (ses->server->sec_mode & SECMODE_USER)) {
+		pSMB->PasswordLength = cpu_to_le16(1);	/* minimum */
+		*bcc_ptr = 0; /* password is null byte */
+		bcc_ptr++;              /* skip password */
+		/* already aligned so no need to do it below */
+	} else {
+		pSMB->PasswordLength = cpu_to_le16(CIFS_AUTH_RESP_SIZE);
+		/* BB FIXME add code to fail this if NTLMv2 or Kerberos
+		   specified as required (when that support is added to
+		   the vfs in the future) as only NTLM or the much
+		   weaker LANMAN (which we do not send by default) is accepted
+		   by Samba (not sure whether other servers allow
+		   NTLMv2 password here) */
+#ifdef CONFIG_CIFS_WEAK_PW_HASH
+		if ((global_secflags & CIFSSEC_MAY_LANMAN) &&
+		    (ses->sectype == LANMAN))
+			calc_lanman_hash(tcon->password, ses->server->cryptkey,
+					 ses->server->sec_mode &
+					    SECMODE_PW_ENCRYPT ? true : false,
+					 bcc_ptr);
+		else
+#endif /* CIFS_WEAK_PW_HASH */
+		rc = SMBNTencrypt(tcon->password, ses->server->cryptkey,
+					bcc_ptr, nls_codepage);
+		if (rc) {
+			cifs_dbg(FYI, "%s Can't generate NTLM rsp. Error: %d\n",
+				 __func__, rc);
+			cifs_buf_release(smb_buffer);
+			return rc;
+		}
+
+		bcc_ptr += CIFS_AUTH_RESP_SIZE;
+		if (ses->capabilities & CAP_UNICODE) {
+			/* must align unicode strings */
+			*bcc_ptr = 0; /* null byte password */
+			bcc_ptr++;
+		}
+	}
+
+	if (ses->server->sign)
+		smb_buffer->Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
+
+	if (ses->capabilities & CAP_STATUS32) {
+		smb_buffer->Flags2 |= SMBFLG2_ERR_STATUS;
+	}
+	if (ses->capabilities & CAP_DFS) {
+		smb_buffer->Flags2 |= SMBFLG2_DFS;
+	}
+	if (ses->capabilities & CAP_UNICODE) {
+		smb_buffer->Flags2 |= SMBFLG2_UNICODE;
+		length =
+		    cifs_strtoUTF16((__le16 *) bcc_ptr, tree,
+			6 /* max utf8 char length in bytes */ *
+			(/* server len*/ + 256 /* share len */), nls_codepage);
+		bcc_ptr += 2 * length;	/* convert num 16 bit words to bytes */
+		bcc_ptr += 2;	/* skip trailing null */
+	} else {		/* ASCII */
+		strcpy(bcc_ptr, tree);
+		bcc_ptr += strlen(tree) + 1;
+	}
+	strcpy(bcc_ptr, "?????");
+	bcc_ptr += strlen("?????");
+	bcc_ptr += 1;
+	count = bcc_ptr - &pSMB->Password[0];
+	pSMB->hdr.smb_buf_length = cpu_to_be32(be32_to_cpu(
+					pSMB->hdr.smb_buf_length) + count);
+	pSMB->ByteCount = cpu_to_le16(count);
+
+	rc = SendReceive(xid, ses, smb_buffer, smb_buffer_response, &length,
+			 0);
+
+	/* above now done in SendReceive */
+	if (rc == 0) {
+		bool is_unicode;
+
+		tcon->tidStatus = CifsGood;
+		tcon->need_reconnect = false;
+		tcon->tid = smb_buffer_response->Tid;
+		bcc_ptr = pByteArea(smb_buffer_response);
+		bytes_left = get_bcc(smb_buffer_response);
+		length = strnlen(bcc_ptr, bytes_left - 2);
+		if (smb_buffer->Flags2 & SMBFLG2_UNICODE)
+			is_unicode = true;
+		else
+			is_unicode = false;
+
+
+		/* skip service field (NB: this field is always ASCII) */
+		if (length == 3) {
+			if ((bcc_ptr[0] == 'I') && (bcc_ptr[1] == 'P') &&
+			    (bcc_ptr[2] == 'C')) {
+				cifs_dbg(FYI, "IPC connection\n");
+				tcon->ipc = true;
+				tcon->pipe = true;
+			}
+		} else if (length == 2) {
+			if ((bcc_ptr[0] == 'A') && (bcc_ptr[1] == ':')) {
+				/* the most common case */
+				cifs_dbg(FYI, "disk share connection\n");
+			}
+		}
+		bcc_ptr += length + 1;
+		bytes_left -= (length + 1);
+		strlcpy(tcon->treeName, tree, sizeof(tcon->treeName));
+
+		/* mostly informational -- no need to fail on error here */
+		kfree(tcon->nativeFileSystem);
+		tcon->nativeFileSystem = cifs_strndup_from_utf16(bcc_ptr,
+						      bytes_left, is_unicode,
+						      nls_codepage);
+
+		cifs_dbg(FYI, "nativeFileSystem=%s\n", tcon->nativeFileSystem);
+
+		if ((smb_buffer_response->WordCount == 3) ||
+			 (smb_buffer_response->WordCount == 7))
+			/* field is in same location */
+			tcon->Flags = le16_to_cpu(pSMBr->OptionalSupport);
+		else
+			tcon->Flags = 0;
+		cifs_dbg(FYI, "Tcon flags: 0x%x\n", tcon->Flags);
+	}
+
+	cifs_buf_release(smb_buffer);
+	return rc;
+}
+
+static void delayed_free(struct rcu_head *p)
+{
+	struct cifs_sb_info *sbi = container_of(p, struct cifs_sb_info, rcu);
+	unload_nls(sbi->local_nls);
+	kfree(sbi);
+}
+
+void
+cifs_umount(struct cifs_sb_info *cifs_sb)
+{
+	struct rb_root *root = &cifs_sb->tlink_tree;
+	struct rb_node *node;
+	struct tcon_link *tlink;
+
+	cancel_delayed_work_sync(&cifs_sb->prune_tlinks);
+
+	spin_lock(&cifs_sb->tlink_tree_lock);
+	while ((node = rb_first(root))) {
+		tlink = rb_entry(node, struct tcon_link, tl_rbnode);
+		cifs_get_tlink(tlink);
+		clear_bit(TCON_LINK_IN_TREE, &tlink->tl_flags);
+		rb_erase(node, root);
+
+		spin_unlock(&cifs_sb->tlink_tree_lock);
+		cifs_put_tlink(tlink);
+		spin_lock(&cifs_sb->tlink_tree_lock);
+	}
+	spin_unlock(&cifs_sb->tlink_tree_lock);
+
+	kfree(cifs_sb->mountdata);
+	kfree(cifs_sb->prepath);
+	call_rcu(&cifs_sb->rcu, delayed_free);
+}
+
+int
+cifs_negotiate_protocol(const unsigned int xid, struct cifs_ses *ses)
+{
+	int rc = 0;
+	struct TCP_Server_Info *server = ses->server;
+
+	if (!server->ops->need_neg || !server->ops->negotiate)
+		return -ENOSYS;
+
+	/* only send once per connect */
+	if (!server->ops->need_neg(server))
+		return 0;
+
+	set_credits(server, 1);
+
+	rc = server->ops->negotiate(xid, ses);
+	if (rc == 0) {
+		spin_lock(&GlobalMid_Lock);
+		if (server->tcpStatus == CifsNeedNegotiate)
+			server->tcpStatus = CifsGood;
+		else
+			rc = -EHOSTDOWN;
+		spin_unlock(&GlobalMid_Lock);
+	}
+
+	return rc;
+}
+
+int
+cifs_setup_session(const unsigned int xid, struct cifs_ses *ses,
+		   struct nls_table *nls_info)
+{
+	int rc = -ENOSYS;
+	struct TCP_Server_Info *server = ses->server;
+
+	ses->capabilities = server->capabilities;
+	if (linuxExtEnabled == 0)
+		ses->capabilities &= (~server->vals->cap_unix);
+
+	cifs_dbg(FYI, "Security Mode: 0x%x Capabilities: 0x%x TimeAdjust: %d\n",
+		 server->sec_mode, server->capabilities, server->timeAdj);
+
+	if (ses->auth_key.response) {
+		cifs_dbg(FYI, "Free previous auth_key.response = %p\n",
+			 ses->auth_key.response);
+		kfree(ses->auth_key.response);
+		ses->auth_key.response = NULL;
+		ses->auth_key.len = 0;
+	}
+
+	if (server->ops->sess_setup)
+		rc = server->ops->sess_setup(xid, ses, nls_info);
+
+	if (rc)
+		cifs_dbg(VFS, "Send error in SessSetup = %d\n", rc);
+
+	return rc;
+}
+
+static int
+cifs_set_vol_auth(struct smb_vol *vol, struct cifs_ses *ses)
+{
+	vol->sectype = ses->sectype;
+
+	/* krb5 is special, since we don't need username or pw */
+	if (vol->sectype == Kerberos)
+		return 0;
+
+	return cifs_set_cifscreds(vol, ses);
+}
+
+static struct cifs_tcon *
+cifs_construct_tcon(struct cifs_sb_info *cifs_sb, kuid_t fsuid)
+{
+	int rc;
+	struct cifs_tcon *master_tcon = cifs_sb_master_tcon(cifs_sb);
+	struct cifs_ses *ses;
+	struct cifs_tcon *tcon = NULL;
+	struct smb_vol *vol_info;
+
+	vol_info = kzalloc(sizeof(*vol_info), GFP_KERNEL);
+	if (vol_info == NULL)
+		return ERR_PTR(-ENOMEM);
+
+	vol_info->local_nls = cifs_sb->local_nls;
+	vol_info->linux_uid = fsuid;
+	vol_info->cred_uid = fsuid;
+	vol_info->UNC = master_tcon->treeName;
+	vol_info->retry = master_tcon->retry;
+	vol_info->nocase = master_tcon->nocase;
+	vol_info->nohandlecache = master_tcon->nohandlecache;
+	vol_info->local_lease = master_tcon->local_lease;
+	vol_info->no_lease = master_tcon->no_lease;
+	vol_info->resilient = master_tcon->use_resilient;
+	vol_info->persistent = master_tcon->use_persistent;
+	vol_info->no_linux_ext = !master_tcon->unix_ext;
+	vol_info->linux_ext = master_tcon->posix_extensions;
+	vol_info->sectype = master_tcon->ses->sectype;
+	vol_info->sign = master_tcon->ses->sign;
+	vol_info->seal = master_tcon->seal;
+
+	rc = cifs_set_vol_auth(vol_info, master_tcon->ses);
+	if (rc) {
+		tcon = ERR_PTR(rc);
+		goto out;
+	}
+
+	/* get a reference for the same TCP session */
+	spin_lock(&cifs_tcp_ses_lock);
+	++master_tcon->ses->server->srv_count;
+	spin_unlock(&cifs_tcp_ses_lock);
+
+	ses = cifs_get_smb_ses(master_tcon->ses->server, vol_info);
+	if (IS_ERR(ses)) {
+		tcon = (struct cifs_tcon *)ses;
+		cifs_put_tcp_session(master_tcon->ses->server, 0);
+		goto out;
+	}
+
+	tcon = cifs_get_tcon(ses, vol_info);
+	if (IS_ERR(tcon)) {
+		cifs_put_smb_ses(ses);
+		goto out;
+	}
+
+	if (cap_unix(ses))
+		reset_cifs_unix_caps(0, tcon, NULL, vol_info);
+
+out:
+	kfree(vol_info->username);
+	kzfree(vol_info->password);
+	kfree(vol_info);
+
+	return tcon;
+}
+
+struct cifs_tcon *
+cifs_sb_master_tcon(struct cifs_sb_info *cifs_sb)
+{
+	return tlink_tcon(cifs_sb_master_tlink(cifs_sb));
+}
+
+/* find and return a tlink with given uid */
+static struct tcon_link *
+tlink_rb_search(struct rb_root *root, kuid_t uid)
+{
+	struct rb_node *node = root->rb_node;
+	struct tcon_link *tlink;
+
+	while (node) {
+		tlink = rb_entry(node, struct tcon_link, tl_rbnode);
+
+		if (uid_gt(tlink->tl_uid, uid))
+			node = node->rb_left;
+		else if (uid_lt(tlink->tl_uid, uid))
+			node = node->rb_right;
+		else
+			return tlink;
+	}
+	return NULL;
+}
+
+/* insert a tcon_link into the tree */
+static void
+tlink_rb_insert(struct rb_root *root, struct tcon_link *new_tlink)
+{
+	struct rb_node **new = &(root->rb_node), *parent = NULL;
+	struct tcon_link *tlink;
+
+	while (*new) {
+		tlink = rb_entry(*new, struct tcon_link, tl_rbnode);
+		parent = *new;
+
+		if (uid_gt(tlink->tl_uid, new_tlink->tl_uid))
+			new = &((*new)->rb_left);
+		else
+			new = &((*new)->rb_right);
+	}
+
+	rb_link_node(&new_tlink->tl_rbnode, parent, new);
+	rb_insert_color(&new_tlink->tl_rbnode, root);
+}
+
+/*
+ * Find or construct an appropriate tcon given a cifs_sb and the fsuid of the
+ * current task.
+ *
+ * If the superblock doesn't refer to a multiuser mount, then just return
+ * the master tcon for the mount.
+ *
+ * First, search the rbtree for an existing tcon for this fsuid. If one
+ * exists, then check to see if it's pending construction. If it is then wait
+ * for construction to complete. Once it's no longer pending, check to see if
+ * it failed and either return an error or retry construction, depending on
+ * the timeout.
+ *
+ * If one doesn't exist then insert a new tcon_link struct into the tree and
+ * try to construct a new one.
+ */
+struct tcon_link *
+cifs_sb_tlink(struct cifs_sb_info *cifs_sb)
+{
+	int ret;
+	kuid_t fsuid = current_fsuid();
+	struct tcon_link *tlink, *newtlink;
+
+	if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MULTIUSER))
+		return cifs_get_tlink(cifs_sb_master_tlink(cifs_sb));
+
+	spin_lock(&cifs_sb->tlink_tree_lock);
+	tlink = tlink_rb_search(&cifs_sb->tlink_tree, fsuid);
+	if (tlink)
+		cifs_get_tlink(tlink);
+	spin_unlock(&cifs_sb->tlink_tree_lock);
+
+	if (tlink == NULL) {
+		newtlink = kzalloc(sizeof(*tlink), GFP_KERNEL);
+		if (newtlink == NULL)
+			return ERR_PTR(-ENOMEM);
+		newtlink->tl_uid = fsuid;
+		newtlink->tl_tcon = ERR_PTR(-EACCES);
+		set_bit(TCON_LINK_PENDING, &newtlink->tl_flags);
+		set_bit(TCON_LINK_IN_TREE, &newtlink->tl_flags);
+		cifs_get_tlink(newtlink);
+
+		spin_lock(&cifs_sb->tlink_tree_lock);
+		/* was one inserted after previous search? */
+		tlink = tlink_rb_search(&cifs_sb->tlink_tree, fsuid);
+		if (tlink) {
+			cifs_get_tlink(tlink);
+			spin_unlock(&cifs_sb->tlink_tree_lock);
+			kfree(newtlink);
+			goto wait_for_construction;
+		}
+		tlink = newtlink;
+		tlink_rb_insert(&cifs_sb->tlink_tree, tlink);
+		spin_unlock(&cifs_sb->tlink_tree_lock);
+	} else {
+wait_for_construction:
+		ret = wait_on_bit(&tlink->tl_flags, TCON_LINK_PENDING,
+				  TASK_INTERRUPTIBLE);
+		if (ret) {
+			cifs_put_tlink(tlink);
+			return ERR_PTR(-ERESTARTSYS);
+		}
+
+		/* if it's good, return it */
+		if (!IS_ERR(tlink->tl_tcon))
+			return tlink;
+
+		/* return error if we tried this already recently */
+		if (time_before(jiffies, tlink->tl_time + TLINK_ERROR_EXPIRE)) {
+			cifs_put_tlink(tlink);
+			return ERR_PTR(-EACCES);
+		}
+
+		if (test_and_set_bit(TCON_LINK_PENDING, &tlink->tl_flags))
+			goto wait_for_construction;
+	}
+
+	tlink->tl_tcon = cifs_construct_tcon(cifs_sb, fsuid);
+	clear_bit(TCON_LINK_PENDING, &tlink->tl_flags);
+	wake_up_bit(&tlink->tl_flags, TCON_LINK_PENDING);
+
+	if (IS_ERR(tlink->tl_tcon)) {
+		cifs_put_tlink(tlink);
+		return ERR_PTR(-EACCES);
+	}
+
+	return tlink;
+}
+
+/*
+ * periodic workqueue job that scans tcon_tree for a superblock and closes
+ * out tcons.
+ */
+static void
+cifs_prune_tlinks(struct work_struct *work)
+{
+	struct cifs_sb_info *cifs_sb = container_of(work, struct cifs_sb_info,
+						    prune_tlinks.work);
+	struct rb_root *root = &cifs_sb->tlink_tree;
+	struct rb_node *node;
+	struct rb_node *tmp;
+	struct tcon_link *tlink;
+
+	/*
+	 * Because we drop the spinlock in the loop in order to put the tlink
+	 * it's not guarded against removal of links from the tree. The only
+	 * places that remove entries from the tree are this function and
+	 * umounts. Because this function is non-reentrant and is canceled
+	 * before umount can proceed, this is safe.
+	 */
+	spin_lock(&cifs_sb->tlink_tree_lock);
+	node = rb_first(root);
+	while (node != NULL) {
+		tmp = node;
+		node = rb_next(tmp);
+		tlink = rb_entry(tmp, struct tcon_link, tl_rbnode);
+
+		if (test_bit(TCON_LINK_MASTER, &tlink->tl_flags) ||
+		    atomic_read(&tlink->tl_count) != 0 ||
+		    time_after(tlink->tl_time + TLINK_IDLE_EXPIRE, jiffies))
+			continue;
+
+		cifs_get_tlink(tlink);
+		clear_bit(TCON_LINK_IN_TREE, &tlink->tl_flags);
+		rb_erase(tmp, root);
+
+		spin_unlock(&cifs_sb->tlink_tree_lock);
+		cifs_put_tlink(tlink);
+		spin_lock(&cifs_sb->tlink_tree_lock);
+	}
+	spin_unlock(&cifs_sb->tlink_tree_lock);
+
+	queue_delayed_work(cifsiod_wq, &cifs_sb->prune_tlinks,
+				TLINK_IDLE_EXPIRE);
+}