Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / fs / cifs / connect.c
diff --git a/kernel/fs/cifs/connect.c b/kernel/fs/cifs/connect.c
new file mode 100644 (file)
index 0000000..8383d5e
--- /dev/null
@@ -0,0 +1,4137 @@
+/*
+ *   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/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 <asm/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 "cifspdu.h"
+#include "cifsglob.h"
+#include "cifsproto.h"
+#include "cifs_unicode.h"
+#include "cifs_debug.h"
+#include "cifs_fs_sb.h"
+#include "ntlmssp.h"
+#include "nterr.h"
+#include "rfc1002pdu.h"
+#include "fscache.h"
+
+#define CIFS_PORT 445
+#define RFC1001_PORT 139
+
+extern mempool_t *cifs_req_poolp;
+
+/* 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_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_nocase,
+       Opt_brl, Opt_nobrl,
+       Opt_forcemandatorylock, 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,
+
+       /* 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,
+
+       /* 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_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_nocase, "nocase" },
+       { Opt_nocase, "ignorecase" },
+       { Opt_brl, "brl" },
+       { Opt_nobrl, "nobrl" },
+       { Opt_nobrl, "nolock" },
+       { Opt_forcemandatorylock, "forcemandatorylock" },
+       { Opt_forcemandatorylock, "forcemand" },
+       { Opt_setuids, "setuids" },
+       { Opt_nosetuids, "nosetuids" },
+       { 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_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_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 },
+};
+
+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);
+
+/*
+ * 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;
+#ifdef CONFIG_CIFS_SMB2
+       server->max_read = 0;
+#endif
+
+       cifs_dbg(FYI, "Reconnecting tcp session\n");
+
+       /* 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;
+               ses->ipc_tid = 0;
+               list_for_each(tmp2, &ses->tcon_list) {
+                       tcon = list_entry(tmp2, struct cifs_tcon, tcon_list);
+                       tcon->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;
+       mutex_unlock(&server->srv_mutex);
+
+       /* 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);
+
+       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);
+               rc = generic_ip_connect(server);
+               if (rc) {
+                       cifs_dbg(FYI, "reconnect error %d\n", 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);
+
+       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);
+
+       /*
+        * We cannot send an echo if it is disabled or until the
+        * NEGOTIATE_PROTOCOL request is done, which is indicated by
+        * server->ops->need_neg() == true. Also, no need to ping if
+        * we got a response recently.
+        */
+       if (!server->ops->need_neg || server->ops->need_neg(server) ||
+           (server->ops->can_echo && !server->ops->can_echo(server)) ||
+           time_before(jiffies, server->lstrp + SMB_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, SMB_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 2 echo intervals to make sure we handle such
+        * situations right:
+        * 1s  client sends a normal SMB request
+        * 2s  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 &&
+           time_after(jiffies, server->lstrp + 2 * SMB_ECHO_INTERVAL)) {
+               cifs_dbg(VFS, "Server %s has not responded in %d seconds. Reconnecting...\n",
+                        server->hostname, (2 * SMB_ECHO_INTERVAL) / HZ);
+               cifs_reconnect(server);
+               wake_up(&server->response_q);
+               return true;
+       }
+
+       return false;
+}
+
+/*
+ * kvec_array_init - clone a kvec array, and advance into it
+ * @new:       pointer to memory for cloned array
+ * @iov:       pointer to original array
+ * @nr_segs:   number of members in original array
+ * @bytes:     number of bytes to advance into the cloned array
+ *
+ * This function will copy the array provided in iov to a section of memory
+ * and advance the specified number of bytes into the new array. It returns
+ * the number of segments in the new array. "new" must be at least as big as
+ * the original iov array.
+ */
+static unsigned int
+kvec_array_init(struct kvec *new, struct kvec *iov, unsigned int nr_segs,
+               size_t bytes)
+{
+       size_t base = 0;
+
+       while (bytes || !iov->iov_len) {
+               int copy = min(bytes, iov->iov_len);
+
+               bytes -= copy;
+               base += copy;
+               if (iov->iov_len == base) {
+                       iov++;
+                       nr_segs--;
+                       base = 0;
+               }
+       }
+       memcpy(new, iov, sizeof(*iov) * nr_segs);
+       new->iov_base += base;
+       new->iov_len -= base;
+       return nr_segs;
+}
+
+static struct kvec *
+get_server_iovec(struct TCP_Server_Info *server, unsigned int nr_segs)
+{
+       struct kvec *new_iov;
+
+       if (server->iov && nr_segs <= server->nr_iov)
+               return server->iov;
+
+       /* not big enough -- allocate a new one and release the old */
+       new_iov = kmalloc(sizeof(*new_iov) * nr_segs, GFP_NOFS);
+       if (new_iov) {
+               kfree(server->iov);
+               server->iov = new_iov;
+               server->nr_iov = nr_segs;
+       }
+       return new_iov;
+}
+
+int
+cifs_readv_from_socket(struct TCP_Server_Info *server, struct kvec *iov_orig,
+                      unsigned int nr_segs, unsigned int to_read)
+{
+       int length = 0;
+       int total_read;
+       unsigned int segs;
+       struct msghdr smb_msg;
+       struct kvec *iov;
+
+       iov = get_server_iovec(server, nr_segs);
+       if (!iov)
+               return -ENOMEM;
+
+       smb_msg.msg_control = NULL;
+       smb_msg.msg_controllen = 0;
+
+       for (total_read = 0; to_read; total_read += length, to_read -= length) {
+               try_to_freeze();
+
+               if (server_unresponsive(server)) {
+                       total_read = -ECONNABORTED;
+                       break;
+               }
+
+               segs = kvec_array_init(iov, iov_orig, nr_segs, total_read);
+
+               length = kernel_recvmsg(server->ssocket, &smb_msg,
+                                       iov, segs, to_read, 0);
+
+               if (server->tcpStatus == CifsExiting) {
+                       total_read = -ESHUTDOWN;
+                       break;
+               } else if (server->tcpStatus == CifsNeedReconnect) {
+                       cifs_reconnect(server);
+                       total_read = -ECONNABORTED;
+                       break;
+               } else 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;
+               } else if (length <= 0) {
+                       cifs_dbg(FYI, "Received no data or error: expecting %d\n"
+                                "got %d", to_read, length);
+                       cifs_reconnect(server);
+                       total_read = -ECONNABORTED;
+                       break;
+               }
+       }
+       return total_read;
+}
+
+int
+cifs_read_from_socket(struct TCP_Server_Info *server, char *buf,
+                     unsigned int to_read)
+{
+       struct kvec iov;
+
+       iov.iov_base = buf;
+       iov.iov_len = to_read;
+
+       return cifs_readv_from_socket(server, &iov, 1, to_read);
+}
+
+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;
+       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);
+
+       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 (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->iov);
+       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 = get_rfc1002_length(buf);
+
+       /* make sure this will fit in a large buffer */
+       if (pdu_length > CIFSMaxBufSize + MAX_HEADER_SIZE(server) - 4) {
+               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 + 4);
+       if (length < 0)
+               return length;
+       server->total_read += length;
+
+       dump_smb(buf, server->total_read);
+
+       /*
+        * 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);
+       if (length != 0)
+               cifs_dump_mem("Bad SMB: ", buf,
+                       min_t(unsigned int, server->total_read, 48));
+
+       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 int
+cifs_demultiplex_thread(void *p)
+{
+       int length;
+       struct TCP_Server_Info *server = p;
+       unsigned int pdu_length;
+       char *buf = NULL;
+       struct task_struct *task_to_wake = NULL;
+       struct mid_q_entry *mid_entry;
+
+       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();
+       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;
+               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;
+
+               /* make sure we have enough to get to the MID */
+               if (pdu_length < HEADER_SIZE(server) - 1 - 4) {
+                       cifs_dbg(VFS, "SMB response too short (%u bytes)\n",
+                                pdu_length);
+                       cifs_reconnect(server);
+                       wake_up(&server->response_q);
+                       continue;
+               }
+
+               /* read down to the MID */
+               length = cifs_read_from_socket(server, buf + 4,
+                                              HEADER_SIZE(server) - 1 - 4);
+               if (length < 0)
+                       continue;
+               server->total_read += length;
+
+               mid_entry = server->ops->find_mid(server, buf);
+
+               if (!mid_entry || !mid_entry->receive)
+                       length = standard_receive3(server, mid_entry);
+               else
+                       length = mid_entry->receive(server, mid_entry);
+
+               if (length < 0)
+                       continue;
+
+               if (server->large_buf)
+                       buf = server->bigbuf;
+
+               server->lstrp = jiffies;
+               if (mid_entry != NULL) {
+                       if (!mid_entry->multiRsp || mid_entry->multiEnd)
+                               mid_entry->callback(mid_entry);
+               } else if (!server->ops->is_oplock_break ||
+                          !server->ops->is_oplock_break(buf, server)) {
+                       cifs_dbg(VFS, "No task to wake, unknown frame received! NumMids %d\n",
+                                atomic_read(&midCount));
+                       cifs_dump_mem("Received Data is: ", buf,
+                                     HEADER_SIZE(server));
+#ifdef CONFIG_CIFS_DEBUG2
+                       if (server->ops->dump_detail)
+                               server->ops->dump_detail(buf);
+                       cifs_dump_mids(server);
+#endif /* CIFS_DEBUG2 */
+
+               }
+       } /* 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)
+{
+       substring_t args[MAX_OPT_ARGS];
+
+       switch (match_token(value, cifs_smb_version_tokens, args)) {
+       case Smb_1:
+               vol->ops = &smb1_operations;
+               vol->vals = &smb1_values;
+               break;
+#ifdef CONFIG_CIFS_SMB2
+       case Smb_20:
+               vol->ops = &smb20_operations;
+               vol->vals = &smb20_values;
+               break;
+       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;
+#endif
+       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;
+
+       /* 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, '\\');
+
+       /* If pos is NULL, or is a bogus trailing delimiter then no prepath */
+       if (!*pos++ || !*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)
+{
+       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;
+       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;
+
+       /* FIXME: add autonegotiation -- for now, SMB1 is default */
+       vol->ops = &smb1_operations;
+       vol->vals = &smb1_values;
+
+       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_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:
+                       vol->no_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_forcemandatorylock:
+                       vol->mand_lock = 1;
+                       break;
+               case Opt_setuids:
+                       vol->setuids = 1;
+                       break;
+               case Opt_nosetuids:
+                       vol->setuids = 0;
+                       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;
+
+               /* 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;
+
+               /* 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 */
+                               kfree(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;
+                       }
+
+                       kfree(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:
+                       string = match_strdup(args);
+                       if (string == NULL)
+                               goto out_nomem;
+
+                       if (strncasecmp(string, "1", 1) == 0) {
+                               /* This is the default */
+                               break;
+                       }
+                       /* For all other value, error */
+                       pr_warn("CIFS: Invalid version specified\n");
+                       goto cifs_parse_mount_err;
+               case Opt_vers:
+                       string = match_strdup(args);
+                       if (string == NULL)
+                               goto out_nomem;
+
+                       if (cifs_parse_smb_version(string, vol) != 0)
+                               goto cifs_parse_mount_err;
+                       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;
+       }
+
+#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) {
+               /* No ip= option specified? Try to get it from UNC */
+               if (!cifs_convert_address(dstaddr, &vol->UNC[2],
+                                               strlen(&vol->UNC[2]))) {
+                       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");
+
+       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 (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;
+
+       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;
+
+       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;
+}
+
+static void
+cifs_put_tcp_session(struct TCP_Server_Info *server)
+{
+       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);
+
+       spin_lock(&GlobalMid_Lock);
+       server->tcpStatus = CifsExiting;
+       spin_unlock(&GlobalMid_Lock);
+
+       cifs_crypto_shash_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)
+               force_sig(SIGKILL, task);
+}
+
+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->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);
+       memcpy(&tcp_ses->srcaddr, &volume_info->srcaddr,
+              sizeof(tcp_ses->srcaddr));
+       memcpy(&tcp_ses->dstaddr, &volume_info->dstaddr,
+               sizeof(tcp_ses->dstaddr));
+#ifdef CONFIG_CIFS_SMB2
+       get_random_bytes(tcp_ses->client_guid, SMB2_CLIENT_GUID_SIZE);
+#endif
+       /*
+        * 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;
+
+       rc = ip_connect(tcp_ses);
+       if (rc < 0) {
+               cifs_dbg(VFS, "Error connecting to socket. Aborting operation.\n");
+               goto out_err_crypto_release;
+       }
+
+       /*
+        * 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, SMB_ECHO_INTERVAL);
+
+       return tcp_ses;
+
+out_err_crypto_release:
+       cifs_crypto_shash_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;
+}
+
+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);
+
+       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);
+}
+
+#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;
+       char *desc, *delim, *payload;
+       ssize_t len;
+       struct key *key;
+       struct TCP_Server_Info *server = ses->server;
+       struct sockaddr_in *sa;
+       struct sockaddr_in6 *sa6;
+       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;
+               }
+       }
+
+       down_read(&key->sem);
+       upayload = key->payload.data;
+       if (IS_ERR_OR_NULL(upayload)) {
+               rc = upayload ? PTR_ERR(upayload) : -EINVAL;
+               goto out_key_put;
+       }
+
+       /* find first : in payload */
+       payload = (char *)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;
+       }
+
+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 */
+
+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);
+               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;
+       }
+       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);
+       return ses;
+
+get_ses_fail:
+       sesInfoFree(ses);
+       free_xid(xid);
+       return ERR_PTR(rc);
+}
+
+static int match_tcon(struct cifs_tcon *tcon, const char *unc)
+{
+       if (tcon->tidStatus == CifsExiting)
+               return 0;
+       if (strncmp(tcon->treeName, unc, MAX_TREE_SIZE))
+               return 0;
+       return 1;
+}
+
+static struct cifs_tcon *
+cifs_find_tcon(struct cifs_ses *ses, const char *unc)
+{
+       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, unc))
+                       continue;
+               ++tcon->tc_count;
+               spin_unlock(&cifs_tcp_ses_lock);
+               return tcon;
+       }
+       spin_unlock(&cifs_tcp_ses_lock);
+       return NULL;
+}
+
+static void
+cifs_put_tcon(struct cifs_tcon *tcon)
+{
+       unsigned int xid;
+       struct cifs_ses *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);
+}
+
+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->UNC);
+       if (tcon) {
+               cifs_dbg(FYI, "Found match on UNC path\n");
+               /* existing tcon already has a reference */
+               cifs_put_smb_ses(ses);
+               if (tcon->seal != volume_info->seal)
+                       cifs_dbg(VFS, "transport encryption setting conflicts with existing tid\n");
+               return tcon;
+       }
+
+       if (!ses->server->ops->tree_connect) {
+               rc = -ENOSYS;
+               goto out_fail;
+       }
+
+       tcon = tconInfoAlloc();
+       if (tcon == NULL) {
+               rc = -ENOMEM;
+               goto out_fail;
+       }
+
+       tcon->ses = ses;
+       if (volume_info->password) {
+               tcon->password = kstrdup(volume_info->password, GFP_KERNEL);
+               if (!tcon->password) {
+                       rc = -ENOMEM;
+                       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->seal = volume_info->seal;
+       /*
+        * 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->local_lease = volume_info->local_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 inline struct tcon_link *
+cifs_sb_master_tlink(struct cifs_sb_info *cifs_sb)
+{
+       return cifs_sb->master_tlink;
+}
+
+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;
+
+       if ((sb->s_flags & CIFS_MS_MASK) != (mnt_data->flags & CIFS_MS_MASK))
+               return 0;
+
+       if ((old->mnt_cifs_flags & CIFS_MOUNT_MASK) !=
+           (new->mnt_cifs_flags & CIFS_MOUNT_MASK))
+               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;
+}
+
+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 (IS_ERR(tlink)) {
+               spin_unlock(&cifs_tcp_ses_lock);
+               return rc;
+       }
+       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->UNC)) {
+               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)
+{
+       char *temp_unc;
+       int rc = 0;
+
+       if (!ses->server->ops->tree_connect || !ses->server->ops->get_dfs_refer)
+               return -ENOSYS;
+
+       *num_referrals = 0;
+       *referrals = NULL;
+
+       if (ses->ipc_tid == 0) {
+               temp_unc = kmalloc(2 /* for slashes */ +
+                       strnlen(ses->serverName, SERVER_NAME_LEN_WITH_NULL * 2)
+                               + 1 + 4 /* slash IPC$ */ + 2, GFP_KERNEL);
+               if (temp_unc == NULL)
+                       return -ENOMEM;
+               temp_unc[0] = '\\';
+               temp_unc[1] = '\\';
+               strcpy(temp_unc + 2, ses->serverName);
+               strcpy(temp_unc + 2 + strlen(ses->serverName), "\\IPC$");
+               rc = ses->server->ops->tree_connect(xid, ses, temp_unc, NULL,
+                                                   nls_codepage);
+               cifs_dbg(FYI, "Tcon rc = %d ipc_tid = %d\n", rc, ses->ipc_tid);
+               kfree(temp_unc);
+       }
+       if (rc == 0)
+               rc = ses->server->ops->get_dfs_refer(xid, ses, old_path,
+                                                    referrals, num_referrals,
+                                                    nls_codepage, remap);
+       /*
+        * BB - map targetUNCs to dfs_info3 structures, here or in
+        * ses->server->ops->get_dfs_refer.
+        */
+
+       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_owned_by_user(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_owned_by_user(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 &&
+                   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");
+
+               }
+       }
+}
+
+void 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: 0x%hx  dir mode: 0x%hx\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->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->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");
+}
+
+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);
+               }
+               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)
+{
+       int rc = 0;
+
+       if (cifs_parse_mount_options(mount_data, devname, volume_info))
+               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)
+{
+       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);
+       if (rc) {
+               cifs_cleanup_volume_info(volume_info);
+               volume_info = ERR_PTR(rc);
+       }
+
+       return volume_info;
+}
+
+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
+
+       rc = bdi_setup_and_register(&cifs_sb->bdi, "cifs");
+       if (rc)
+               return rc;
+
+#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);
+
+               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);
+               bdi_destroy(&cifs_sb->bdi);
+               goto out;
+       }
+
+       /* 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;
+       }
+
+       /* 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;
+               goto remote_path_check;
+       }
+
+       /* 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->ipc && 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);
+
+       /* tune readahead according to rsize */
+       cifs_sb->bdi.ra_pages = cifs_sb->rsize / PAGE_CACHE_SIZE;
+
+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);
+               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;
+               }
+               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);
+               bdi_destroy(&cifs_sb->bdi);
+       }
+
+out:
+       free_xid(xid);
+       return rc;
+}
+
+/*
+ * Issue a TREE_CONNECT request. Note that for IPC$ shares, that the tcon
+ * pointer may be NULL.
+ */
+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 || (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) && (tcon != NULL)) {
+               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 = 1;
+                       }
+               } 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);
+       } else if ((rc == 0) && tcon == NULL) {
+               /* all we need to save for IPC$ connection */
+               ses->ipc_tid = smb_buffer_response->Tid;
+       }
+
+       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);
+
+       bdi_destroy(&cifs_sb->bdi);
+       kfree(cifs_sb->mountdata);
+       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 (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->local_lease = master_tcon->local_lease;
+       vol_info->no_linux_ext = !master_tcon->unix_ext;
+       vol_info->sectype = master_tcon->ses->sectype;
+       vol_info->sign = master_tcon->ses->sign;
+
+       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);
+               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);
+       kfree(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 = rb_first(root);
+       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);
+}