6 files changed, 96 insertions, 150 deletions

diff --git a/fs/cifs/cifs_debug.c b/fs/cifs/cifs_debug.c
index ba8723d95996..40b5108fb4f9 100644
--- a/fs/cifs/cifs_debug.c
+++ b/fs/cifs/cifs_debug.c
@@ -144,7 +144,7 @@ static int cifs_debug_data_proc_show(struct seq_file *m, void *v)
                         seq_printf(m, "TCP status: %d\n\tLocal Users To "
                                     "Server: %d SecMode: 0x%x Req On Wire: %d",
                                 ses->server->tcpStatus,
-                                atomic_read(&ses->server->socketUseCount),
+                                ses->server->srv_count,
                                 ses->server->secMode,
                                 atomic_read(&ses->server->inFlight));
 
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index af16a2406b1c..2946dab0718f 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -1059,7 +1059,7 @@ init_cifs(void)
 {
         int rc = 0;
         cifs_proc_init();
-        INIT_LIST_HEAD(&global_cifs_sock_list);
+        INIT_LIST_HEAD(&cifs_tcp_ses_list);
         INIT_LIST_HEAD(&GlobalSMBSessionList); /* BB to be removed by jl */
         INIT_LIST_HEAD(&GlobalTreeConnectionList); /* BB to be removed by jl */
         INIT_LIST_HEAD(&GlobalOplock_Q);
@@ -1089,6 +1089,7 @@ init_cifs(void)
         GlobalMaxActiveXid = 0;
         memset(Local_System_Name, 0, 15);
         rwlock_init(&GlobalSMBSeslock);
+        rwlock_init(&cifs_tcp_ses_lock);
         spin_lock_init(&GlobalMid_Lock);
 
         if (cifs_max_pending < 2) {
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index 13dc48414a78..313f7bfedec7 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -123,6 +123,7 @@ struct cifs_cred {
 struct TCP_Server_Info {
         struct list_head tcp_ses_list;
         struct list_head smb_ses_list;
+        int srv_count; /* reference counter */
         /* 15 character server name + 0x20 16th byte indicating type = srv */
         char server_RFC1001_name[SERVER_NAME_LEN_WITH_NULL];
         char unicode_server_Name[SERVER_NAME_LEN_WITH_NULL * 2];
@@ -144,7 +145,6 @@ struct TCP_Server_Info {
         bool svlocal:1;                 /* local server or remote */
         bool noblocksnd;                /* use blocking sendmsg */
         bool noautotune;                /* do not autotune send buf sizes */
-        atomic_t socketUseCount; /* number of open cifs sessions on socket */
         atomic_t inFlight;  /* number of requests on the wire to server */
 #ifdef CONFIG_CIFS_STATS2
         atomic_t inSend; /* requests trying to send */
@@ -591,13 +591,18 @@ require use of the stronger protocol */
 #define GLOBAL_EXTERN extern
 #endif
 
-
-/* the list of TCP_Server_Info structures, ie each of the sockets
+/*
+ * the list of TCP_Server_Info structures, ie each of the sockets
  * connecting our client to a distinct server (ip address), is
- * chained together by global_cifs_sock_list. The list of all our SMB
+ * chained together by cifs_tcp_ses_list. The list of all our SMB
  * sessions (and from that the tree connections) can be found
- * by iterating over global_cifs_sock_list */
-GLOBAL_EXTERN struct list_head global_cifs_sock_list;
+ * by iterating over cifs_tcp_ses_list
+ */
+GLOBAL_EXTERN struct list_head          cifs_tcp_ses_list;
+
+/* protects cifs_tcp_ses_list and srv_count for each tcp session */
+GLOBAL_EXTERN rwlock_t          cifs_tcp_ses_lock;
+
 GLOBAL_EXTERN struct list_head GlobalSMBSessionList; /* BB to be removed by jl*/
 GLOBAL_EXTERN struct list_head GlobalTreeConnectionList; /* BB to be removed */
 GLOBAL_EXTERN rwlock_t GlobalSMBSeslock;  /* protects list inserts on 3 above */
diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h
index 6f21ecb85ce5..0250a994c6e6 100644
--- a/fs/cifs/cifsproto.h
+++ b/fs/cifs/cifsproto.h
@@ -102,6 +102,7 @@ extern void acl_to_uid_mode(struct inode *inode, const char *path,
                             const __u16 *pfid);
 extern int mode_to_acl(struct inode *inode, const char *path, __u64);
 
+extern void cifs_put_tcp_session(struct TCP_Server_Info *server);
 extern int cifs_mount(struct super_block *, struct cifs_sb_info *, char *,
                         const char *);
 extern int cifs_umount(struct super_block *, struct cifs_sb_info *);
diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
index 7f0651b69573..cd9e9a145e4d 100644
--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -664,8 +664,9 @@ CIFSSMBNegotiate(unsigned int xid, struct cifsSesInfo *ses)
                         rc = -EIO;
                         goto neg_err_exit;
                 }
-
-                if (server->socketUseCount.counter > 1) {
+                read_lock(&cifs_tcp_ses_lock);
+                if (server->srv_count > 1) {
+                        read_unlock(&cifs_tcp_ses_lock);
                         if (memcmp(server->server_GUID,
                                    pSMBr->u.extended_response.
                                    GUID, 16) != 0) {
@@ -674,9 +675,11 @@ CIFSSMBNegotiate(unsigned int xid, struct cifsSesInfo *ses)
                                         pSMBr->u.extended_response.GUID,
                                         16);
                         }
-                } else
+                } else {
+                        read_unlock(&cifs_tcp_ses_lock);
                         memcpy(server->server_GUID,
                                pSMBr->u.extended_response.GUID, 16);
+                }
 
                 if (count == 16) {
                         server->secType = RawNTLMSSP;
@@ -830,12 +833,9 @@ CIFSSMBLogoff(const int xid, struct cifsSesInfo *ses)
         pSMB->AndXCommand = 0xFF;
         rc = SendReceiveNoRsp(xid, ses, (struct smb_hdr *) pSMB, 0);
 session_already_dead:
-        atomic_dec(&ses->server->socketUseCount);
-        if (atomic_read(&ses->server->socketUseCount) == 0) {
-                spin_lock(&GlobalMid_Lock);
-                ses->server->tcpStatus = CifsExiting;
-                spin_unlock(&GlobalMid_Lock);
-                rc = -ESHUTDOWN;
+        if (ses->server) {
+                cifs_put_tcp_session(ses->server);
+                rc = 0;
         }
         up(&ses->sesSem);
 
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 30ab8dc68e17..a0314259f94d 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -659,6 +659,11 @@ multi_t2_fnd:
                 }
         } /* end while !EXITING */
 
+        /* take it off the list, if it's not already */
+        write_lock(&cifs_tcp_ses_lock);
+        list_del_init(&server->tcp_ses_list);
+        write_unlock(&cifs_tcp_ses_lock);
+
         spin_lock(&GlobalMid_Lock);
         server->tcpStatus = CifsExiting;
         spin_unlock(&GlobalMid_Lock);
@@ -1357,92 +1362,66 @@ cifs_parse_mount_options(char *options, const char *devname,
         return 0;
 }
 
-static struct cifsSesInfo *
-cifs_find_tcp_session(struct in_addr *target_ip_addr,
-                      struct in6_addr *target_ip6_addr,
-                      char *userName, struct TCP_Server_Info **psrvTcp)
+static struct TCP_Server_Info *
+cifs_find_tcp_session(struct sockaddr *addr)
 {
         struct list_head *tmp;
-        struct cifsSesInfo *ses;
-
-        *psrvTcp = NULL;
-
-        read_lock(&GlobalSMBSeslock);
-        list_for_each(tmp, &GlobalSMBSessionList) {
-                ses = list_entry(tmp, struct cifsSesInfo, cifsSessionList);
-                if (!ses->server)
+        struct TCP_Server_Info *server;
+        struct sockaddr_in *addr4 = (struct sockaddr_in *) addr;
+        struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *) addr;
+
+        write_lock(&cifs_tcp_ses_lock);
+        list_for_each(tmp, &cifs_tcp_ses_list) {
+                server = list_entry(tmp, struct TCP_Server_Info,
+                                    tcp_ses_list);
+
+                /*
+                 * the demux thread can exit on its own while still in CifsNew
+                 * so don't accept any sockets in that state. Since the
+                 * tcpStatus never changes back to CifsNew it's safe to check
+                 * for this without a lock.
+                 */
+                if (server->tcpStatus == CifsNew)
                         continue;
 
-                if (target_ip_addr &&
-                    ses->server->addr.sockAddr.sin_addr.s_addr != target_ip_addr->s_addr)
-                                continue;
-                else if (target_ip6_addr &&
-                         memcmp(&ses->server->addr.sockAddr6.sin6_addr,
-                                target_ip6_addr, sizeof(*target_ip6_addr)))
-                                continue;
-                /* BB lock server and tcp session; increment use count here?? */
-
-                /* found a match on the TCP session */
-                *psrvTcp = ses->server;
+                if (addr->sa_family == AF_INET &&
+                    (addr4->sin_addr.s_addr !=
+                     server->addr.sockAddr.sin_addr.s_addr))
+                        continue;
+                else if (addr->sa_family == AF_INET6 &&
+                         memcmp(&server->addr.sockAddr6.sin6_addr,
+                                &addr6->sin6_addr, sizeof(addr6->sin6_addr)))
+                        continue;
 
-                /* BB check if reconnection needed */
-                if (strncmp(ses->userName, userName, MAX_USERNAME_SIZE) == 0) {
-                        read_unlock(&GlobalSMBSeslock);
-                        /* Found exact match on both TCP and
-                           SMB sessions */
-                        return ses;
-                }
-                /* else tcp and smb sessions need reconnection */
+                ++server->srv_count;
+                write_unlock(&cifs_tcp_ses_lock);
+                return server;
         }
-        read_unlock(&GlobalSMBSeslock);
-
+        write_unlock(&cifs_tcp_ses_lock);
         return NULL;
 }
 
-static struct cifsTconInfo *
-find_unc(__be32 new_target_ip_addr, char *uncName, char *userName)
+void
+cifs_put_tcp_session(struct TCP_Server_Info *server)
 {
-        struct list_head *tmp;
-        struct cifsTconInfo *tcon;
-        __be32 old_ip;
-
-        read_lock(&GlobalSMBSeslock);
-
-        list_for_each(tmp, &GlobalTreeConnectionList) {
-                cFYI(1, ("Next tcon"));
-                tcon = list_entry(tmp, struct cifsTconInfo, cifsConnectionList);
-                if (!tcon->ses || !tcon->ses->server)
-                        continue;
-
-                old_ip = tcon->ses->server->addr.sockAddr.sin_addr.s_addr;
-                cFYI(1, ("old ip addr: %x == new ip %x ?",
-                        old_ip, new_target_ip_addr));
-
-                if (old_ip != new_target_ip_addr)
-                        continue;
-
-                /* BB lock tcon, server, tcp session and increment use count? */
-                /* found a match on the TCP session */
-                /* BB check if reconnection needed */
-                cFYI(1, ("IP match, old UNC: %s new: %s",
-                        tcon->treeName, uncName));
+        struct task_struct *task;
 
-                if (strncmp(tcon->treeName, uncName, MAX_TREE_SIZE))
-                        continue;
+        write_lock(&cifs_tcp_ses_lock);
+        if (--server->srv_count > 0) {
+                write_unlock(&cifs_tcp_ses_lock);
+                return;
+        }
 
-                cFYI(1, ("and old usr: %s new: %s",
-                        tcon->treeName, uncName));
+        list_del_init(&server->tcp_ses_list);
+        write_unlock(&cifs_tcp_ses_lock);
 
-                if (strncmp(tcon->ses->userName, userName, MAX_USERNAME_SIZE))
-                        continue;
-
-                /* matched smb session (user name) */
-                read_unlock(&GlobalSMBSeslock);
-                return tcon;
-        }
+        spin_lock(&GlobalMid_Lock);
+        server->tcpStatus = CifsExiting;
+        spin_unlock(&GlobalMid_Lock);
 
-        read_unlock(&GlobalSMBSeslock);
-        return NULL;
+        task = xchg(&server->tsk, NULL);
+        if (task)
+                force_sig(SIGKILL, task);
 }
 
 int
@@ -1881,16 +1860,6 @@ convert_delimiter(char *path, char delim)
         }
 }
 
-static void
-kill_cifsd(struct TCP_Server_Info *server)
-{
-        struct task_struct *task;
-
-        task = xchg(&server->tsk, NULL);
-        if (task)
-                force_sig(SIGKILL, task);
-}
-
 static void setup_cifs_sb(struct smb_vol *pvolume_info,
                           struct cifs_sb_info *cifs_sb)
 {
@@ -2069,21 +2038,10 @@ cifs_mount(struct super_block *sb, struct cifs_sb_info *cifs_sb,
                 }
         }
 
-        if (addr.sa_family == AF_INET)
-                existingCifsSes = cifs_find_tcp_session(&sin_server->sin_addr,
-                        NULL /* no ipv6 addr */,
-                        volume_info.username, &srvTcp);
-        else if (addr.sa_family == AF_INET6) {
-                cFYI(1, ("looking for ipv6 address"));
-                existingCifsSes = cifs_find_tcp_session(NULL /* no ipv4 addr */,
-                        &sin_server6->sin6_addr,
-                        volume_info.username, &srvTcp);
-        } else {
-                rc = -EINVAL;
-                goto out;
-        }
-
-        if (!srvTcp) {
+        srvTcp = cifs_find_tcp_session(&addr);
+        if (srvTcp) {
+                cFYI(1, ("Existing tcp session with server found"));
+        } else {        /* create socket */
                 if (addr.sa_family == AF_INET6) {
                         cFYI(1, ("attempting ipv6 connect"));
                         /* BB should we allow ipv6 on port 139? */
@@ -2153,6 +2111,12 @@ cifs_mount(struct super_block *sb, struct cifs_sb_info *cifs_sb,
                         memcpy(srvTcp->server_RFC1001_name,
                                 volume_info.target_rfc1001_name, 16);
                         srvTcp->sequence_number = 0;
+                        INIT_LIST_HEAD(&srvTcp->tcp_ses_list);
+                        ++srvTcp->srv_count;
+                        write_lock(&cifs_tcp_ses_lock);
+                        list_add(&srvTcp->tcp_ses_list,
+                                 &cifs_tcp_ses_list);
+                        write_unlock(&cifs_tcp_ses_lock);
                 }
         }
 
@@ -2204,8 +2168,6 @@ cifs_mount(struct super_block *sb, struct cifs_sb_info *cifs_sb,
                         rc = cifs_setup_session(xid, pSesInfo,
                                                 cifs_sb->local_nls);
                         up(&pSesInfo->sesSem);
-                        if (!rc)
-                                atomic_inc(&srvTcp->socketUseCount);
                 }
         }
 
@@ -2213,9 +2175,6 @@ cifs_mount(struct super_block *sb, struct cifs_sb_info *cifs_sb,
         if (!rc) {
                 setup_cifs_sb(&volume_info, cifs_sb);
 
-                tcon =
-                    find_unc(sin_server->sin_addr.s_addr, volume_info.UNC,
-                             volume_info.username);
                 if (tcon) {
                         cFYI(1, ("Found match on UNC path"));
                         if (tcon->seal != volume_info.seal)
@@ -2278,35 +2237,21 @@ cifs_mount(struct super_block *sb, struct cifs_sb_info *cifs_sb,
 /* on error free sesinfo and tcon struct if needed */
 mount_fail_check:
         if (rc) {
-                /* if session setup failed, use count is zero but
-                we still need to free cifsd thread */
-                if (atomic_read(&srvTcp->socketUseCount) == 0) {
-                        spin_lock(&GlobalMid_Lock);
-                        srvTcp->tcpStatus = CifsExiting;
-                        spin_unlock(&GlobalMid_Lock);
-                        kill_cifsd(srvTcp);
-                }
-                 /* If find_unc succeeded then rc == 0 so we can not end */
-                if (tcon)  /* up accidently freeing someone elses tcon struct */
+                /* If find_unc succeeded then rc == 0 so we can not end */
+                /* up accidently freeing someone elses tcon struct */
+                if (tcon)
                         tconInfoFree(tcon);
+
                 if (existingCifsSes == NULL) {
                         if (pSesInfo) {
                                 if ((pSesInfo->server) &&
-                                    (pSesInfo->status == CifsGood)) {
-                                        int temp_rc;
-                                        temp_rc = CIFSSMBLogoff(xid, pSesInfo);
-                                        /* if the socketUseCount is now zero */
-                                        if ((temp_rc == -ESHUTDOWN) &&
-                                            (pSesInfo->server))
-                                                kill_cifsd(pSesInfo->server);
-                                } else {
+                                    (pSesInfo->status == CifsGood))
+                                        CIFSSMBLogoff(xid, pSesInfo);
+                                else {
                                         cFYI(1, ("No session or bad tcon"));
-                                        if (pSesInfo->server) {
-                                                spin_lock(&GlobalMid_Lock);
-                                                srvTcp->tcpStatus = CifsExiting;
-                                                spin_unlock(&GlobalMid_Lock);
-                                                kill_cifsd(pSesInfo->server);
-                                        }
+                                        if (pSesInfo->server)
+                                                cifs_put_tcp_session(
+                                                        pSesInfo->server);
                                 }
                                 sesInfoFree(pSesInfo);
                                 /* pSesInfo = NULL; */
@@ -3613,13 +3558,7 @@ cifs_umount(struct super_block *sb, struct cifs_sb_info *cifs_sb)
                         if (rc == -EBUSY) {
                                 FreeXid(xid);
                                 return 0;
-                        } else if (rc == -ESHUTDOWN) {
-                                cFYI(1, ("Waking up socket by sending signal"));
-                                if (ses->server)
-                                        kill_cifsd(ses->server);
-                                rc = 0;
-                        } /* else - we have an smb session
-                                left on this socket do not kill cifsd */
+                        }
                 } else
                         cFYI(1, ("No session or bad tcon"));
         }