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authorJeff Layton <jlayton@redhat.com>2013-09-05 08:38:11 -0400
committerSteve French <smfrench@gmail.com>2013-09-08 14:24:10 -0500
commit30706a545417af50f07b8e47cc2189a2e20a4636 (patch)
tree1dc52316aaa356ba728ec0b612799c314fb9d410 /Documentation
parent73e216a8a42c0ef3d08071705c946c38fdbe12b0 (diff)
downloadop-kernel-dev-30706a545417af50f07b8e47cc2189a2e20a4636.zip
op-kernel-dev-30706a545417af50f07b8e47cc2189a2e20a4636.tar.gz
cifs: create a new Documentation/ directory and move docfiles into it
Currently, we have a number of documentation files that live under fs/cifs/. Generally, these don't get picked up by distro packagers, since they're in a non-standard location. Move them to a new spot under Documentation/ instead. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Steve French <smfrench@gmail.com>
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/filesystems/cifs/AUTHORS55
-rw-r--r--Documentation/filesystems/cifs/CHANGES1065
-rw-r--r--Documentation/filesystems/cifs/README753
-rw-r--r--Documentation/filesystems/cifs/TODO129
-rw-r--r--Documentation/filesystems/cifs/cifs.txt (renamed from Documentation/filesystems/cifs.txt)0
5 files changed, 2002 insertions, 0 deletions
diff --git a/Documentation/filesystems/cifs/AUTHORS b/Documentation/filesystems/cifs/AUTHORS
new file mode 100644
index 0000000..ea940b1
--- /dev/null
+++ b/Documentation/filesystems/cifs/AUTHORS
@@ -0,0 +1,55 @@
+Original Author
+===============
+Steve French (sfrench@samba.org)
+
+The author wishes to express his appreciation and thanks to:
+Andrew Tridgell (Samba team) for his early suggestions about smb/cifs VFS
+improvements. Thanks to IBM for allowing me time and test resources to pursue
+this project, to Jim McDonough from IBM (and the Samba Team) for his help, to
+the IBM Linux JFS team for explaining many esoteric Linux filesystem features.
+Jeremy Allison of the Samba team has done invaluable work in adding the server
+side of the original CIFS Unix extensions and reviewing and implementing
+portions of the newer CIFS POSIX extensions into the Samba 3 file server. Thank
+Dave Boutcher of IBM Rochester (author of the OS/400 smb/cifs filesystem client)
+for proving years ago that very good smb/cifs clients could be done on Unix-like
+operating systems. Volker Lendecke, Andrew Tridgell, Urban Widmark, John
+Newbigin and others for their work on the Linux smbfs module. Thanks to
+the other members of the Storage Network Industry Association CIFS Technical
+Workgroup for their work specifying this highly complex protocol and finally
+thanks to the Samba team for their technical advice and encouragement.
+
+Patch Contributors
+------------------
+Zwane Mwaikambo
+Andi Kleen
+Amrut Joshi
+Shobhit Dayal
+Sergey Vlasov
+Richard Hughes
+Yury Umanets
+Mark Hamzy (for some of the early cifs IPv6 work)
+Domen Puncer
+Jesper Juhl (in particular for lots of whitespace/formatting cleanup)
+Vince Negri and Dave Stahl (for finding an important caching bug)
+Adrian Bunk (kcalloc cleanups)
+Miklos Szeredi
+Kazeon team for various fixes especially for 2.4 version.
+Asser Ferno (Change Notify support)
+Shaggy (Dave Kleikamp) for innumerable small fs suggestions and some good cleanup
+Gunter Kukkukk (testing and suggestions for support of old servers)
+Igor Mammedov (DFS support)
+Jeff Layton (many, many fixes, as well as great work on the cifs Kerberos code)
+
+Test case and Bug Report contributors
+-------------------------------------
+Thanks to those in the community who have submitted detailed bug reports
+and debug of problems they have found: Jochen Dolze, David Blaine,
+Rene Scharfe, Martin Josefsson, Alexander Wild, Anthony Liguori,
+Lars Muller, Urban Widmark, Massimiliano Ferrero, Howard Owen,
+Olaf Kirch, Kieron Briggs, Nick Millington and others. Also special
+mention to the Stanford Checker (SWAT) which pointed out many minor
+bugs in error paths. Valuable suggestions also have come from Al Viro
+and Dave Miller.
+
+And thanks to the IBM LTC and Power test teams and SuSE testers for
+finding multiple bugs during excellent stress test runs.
diff --git a/Documentation/filesystems/cifs/CHANGES b/Documentation/filesystems/cifs/CHANGES
new file mode 100644
index 0000000..bc0025c
--- /dev/null
+++ b/Documentation/filesystems/cifs/CHANGES
@@ -0,0 +1,1065 @@
+Version 1.62
+------------
+Add sockopt=TCP_NODELAY mount option. EA (xattr) routines hardened
+to more strictly handle corrupt frames.
+
+Version 1.61
+------------
+Fix append problem to Samba servers (files opened with O_APPEND could
+have duplicated data). Fix oops in cifs_lookup. Workaround problem
+mounting to OS/400 Netserve. Fix oops in cifs_get_tcp_session.
+Disable use of server inode numbers when server only
+partially supports them (e.g. for one server querying inode numbers on
+FindFirst fails but QPathInfo queries works). Fix oops with dfs in
+cifs_put_smb_ses. Fix mmap to work on directio mounts (needed
+for OpenOffice when on forcedirectio mount e.g.)
+
+Version 1.60
+-------------
+Fix memory leak in reconnect. Fix oops in DFS mount error path.
+Set s_maxbytes to smaller (the max that vfs can handle) so that
+sendfile will now work over cifs mounts again. Add noforcegid
+and noforceuid mount parameters. Fix small mem leak when using
+ntlmv2. Fix 2nd mount to same server but with different port to
+be allowed (rather than reusing the 1st port) - only when the
+user explicitly overrides the port on the 2nd mount.
+
+Version 1.59
+------------
+Client uses server inode numbers (which are persistent) rather than
+client generated ones by default (mount option "serverino" turned
+on by default if server supports it). Add forceuid and forcegid
+mount options (so that when negotiating unix extensions specifying
+which uid mounted does not immediately force the server's reported
+uids to be overridden). Add support for scope mount parm. Improve
+hard link detection to use same inode for both. Do not set
+read-only dos attribute on directories (for chmod) since Windows
+explorer special cases this attribute bit for directories for
+a different purpose.
+
+Version 1.58
+------------
+Guard against buffer overruns in various UCS-2 to UTF-8 string conversions
+when the UTF-8 string is composed of unusually long (more than 4 byte) converted
+characters. Add support for mounting root of a share which redirects immediately
+to DFS target. Convert string conversion functions from Unicode to more
+accurately mark string length before allocating memory (which may help the
+rare cases where a UTF-8 string is much larger than the UCS2 string that
+we converted from). Fix endianness of the vcnum field used during
+session setup to distinguish multiple mounts to same server from different
+userids. Raw NTLMSSP fixed (it requires /proc/fs/cifs/experimental
+flag to be set to 2, and mount must enable krb5 to turn on extended security).
+Performance of file create to Samba improved (posix create on lookup
+removes 1 of 2 network requests sent on file create)
+
+Version 1.57
+------------
+Improve support for multiple security contexts to the same server. We
+used to use the same "vcnumber" for all connections which could cause
+the server to treat subsequent connections, especially those that
+are authenticated as guest, as reconnections, invalidating the earlier
+user's smb session. This fix allows cifs to mount multiple times to the
+same server with different userids without risking invalidating earlier
+established security contexts. fsync now sends SMB Flush operation
+to better ensure that we wait for server to write all of the data to
+server disk (not just write it over the network). Add new mount
+parameter to allow user to disable sending the (slow) SMB flush on
+fsync if desired (fsync still flushes all cached write data to the server).
+Posix file open support added (turned off after one attempt if server
+fails to support it properly, as with Samba server versions prior to 3.3.2)
+Fix "redzone overwritten" bug in cifs_put_tcon (CIFSTcon may allocate too
+little memory for the "nativeFileSystem" field returned by the server
+during mount). Endian convert inode numbers if necessary (makes it easier
+to compare inode numbers on network files from big endian systems).
+
+Version 1.56
+------------
+Add "forcemandatorylock" mount option to allow user to use mandatory
+rather than posix (advisory) byte range locks, even though server would
+support posix byte range locks. Fix query of root inode when prefixpath
+specified and user does not have access to query information about the
+top of the share. Fix problem in 2.6.28 resolving DFS paths to
+Samba servers (worked to Windows). Fix rmdir so that pending search
+(readdir) requests do not get invalid results which include the now
+removed directory. Fix oops in cifs_dfs_ref.c when prefixpath is not reachable
+when using DFS. Add better file create support to servers which support
+the CIFS POSIX protocol extensions (this adds support for new flags
+on create, and improves semantics for write of locked ranges).
+
+Version 1.55
+------------
+Various fixes to make delete of open files behavior more predictable
+(when delete of an open file fails we mark the file as "delete-on-close"
+in a way that more servers accept, but only if we can first rename the
+file to a temporary name). Add experimental support for more safely
+handling fcntl(F_SETLEASE). Convert cifs to using blocking tcp
+sends, and also let tcp autotune the socket send and receive buffers.
+This reduces the number of EAGAIN errors returned by TCP/IP in
+high stress workloads (and the number of retries on socket writes
+when sending large SMBWriteX requests). Fix case in which a portion of
+data can in some cases not get written to the file on the server before the
+file is closed. Fix DFS parsing to properly handle path consumed field,
+and to handle certain codepage conversions better. Fix mount and
+umount race that can cause oops in mount or umount or reconnect.
+
+Version 1.54
+------------
+Fix premature write failure on congested networks (we would give up
+on EAGAIN from the socket too quickly on large writes).
+Cifs_mkdir and cifs_create now respect the setgid bit on parent dir.
+Fix endian problems in acl (mode from/to cifs acl) on bigendian
+architectures. Fix problems with preserving timestamps on copying open
+files (e.g. "cp -a") to Windows servers. For mkdir and create honor setgid bit
+on parent directory when server supports Unix Extensions but not POSIX
+create. Update cifs.upcall version to handle new Kerberos sec flags
+(this requires update of cifs.upcall program from Samba). Fix memory leak
+on dns_upcall (resolving DFS referralls). Fix plain text password
+authentication (requires setting SecurityFlags to 0x30030 to enable
+lanman and plain text though). Fix writes to be at correct offset when
+file is open with O_APPEND and file is on a directio (forcediretio) mount.
+Fix bug in rewinding readdir directory searches. Add nodfs mount option.
+
+Version 1.53
+------------
+DFS support added (Microsoft Distributed File System client support needed
+for referrals which enable a hierarchical name space among servers).
+Disable temporary caching of mode bits to servers which do not support
+storing of mode (e.g. Windows servers, when client mounts without cifsacl
+mount option) and add new "dynperm" mount option to enable temporary caching
+of mode (enable old behavior). Fix hang on mount caused when server crashes
+tcp session during negotiate protocol.
+
+Version 1.52
+------------
+Fix oops on second mount to server when null auth is used.
+Enable experimental Kerberos support. Return writebehind errors on flush
+and sync so that events like out of disk space get reported properly on
+cached files. Fix setxattr failure to certain Samba versions. Fix mount
+of second share to disconnected server session (autoreconnect on this).
+Add ability to modify cifs acls for handling chmod (when mounted with
+cifsacl flag). Fix prefixpath path separator so we can handle mounts
+with prefixpaths longer than one directory (one path component) when
+mounted to Windows servers. Fix slow file open when cifsacl
+enabled. Fix memory leak in FindNext when the SMB call returns -EBADF.
+
+
+Version 1.51
+------------
+Fix memory leak in statfs when mounted to very old servers (e.g.
+Windows 9x). Add new feature "POSIX open" which allows servers
+which support the current POSIX Extensions to provide better semantics
+(e.g. delete for open files opened with posix open). Take into
+account umask on posix mkdir not just older style mkdir. Add
+ability to mount to IPC$ share (which allows CIFS named pipes to be
+opened, read and written as if they were files). When 1st tree
+connect fails (e.g. due to signing negotiation failure) fix
+leak that causes cifsd not to stop and rmmod to fail to cleanup
+cifs_request_buffers pool. Fix problem with POSIX Open/Mkdir on
+bigendian architectures. Fix possible memory corruption when
+EAGAIN returned on kern_recvmsg. Return better error if server
+requires packet signing but client has disabled it. When mounted
+with cifsacl mount option - mode bits are approximated based
+on the contents of the ACL of the file or directory. When cifs
+mount helper is missing convert make sure that UNC name
+has backslash (not forward slash) between ip address of server
+and the share name.
+
+Version 1.50
+------------
+Fix NTLMv2 signing. NFS server mounted over cifs works (if cifs mount is
+done with "serverino" mount option). Add support for POSIX Unlink
+(helps with certain sharing violation cases when server such as
+Samba supports newer POSIX CIFS Protocol Extensions). Add "nounix"
+mount option to allow disabling the CIFS Unix Extensions for just
+that mount. Fix hang on spinlock in find_writable_file (race when
+reopening file after session crash). Byte range unlock request to
+windows server could unlock more bytes (on server copy of file)
+than intended if start of unlock request is well before start of
+a previous byte range lock that we issued.
+
+Version 1.49
+------------
+IPv6 support. Enable ipv6 addresses to be passed on mount (put the ipv6
+address after the "ip=" mount option, at least until mount.cifs is fixed to
+handle DNS host to ipv6 name translation). Accept override of uid or gid
+on mount even when Unix Extensions are negotiated (it used to be ignored
+when Unix Extensions were ignored). This allows users to override the
+default uid and gid for files when they are certain that the uids or
+gids on the server do not match those of the client. Make "sec=none"
+mount override username (so that null user connection is attempted)
+to match what documentation said. Support for very large reads, over 127K,
+available to some newer servers (such as Samba 3.0.26 and later but
+note that it also requires setting CIFSMaxBufSize at module install
+time to a larger value which may hurt performance in some cases).
+Make sign option force signing (or fail if server does not support it).
+
+Version 1.48
+------------
+Fix mtime bouncing around from local idea of last write times to remote time.
+Fix hang (in i_size_read) when simultaneous size update of same remote file
+on smp system corrupts sequence number. Do not reread unnecessarily partial page
+(which we are about to overwrite anyway) when writing out file opened rw.
+When DOS attribute of file on non-Unix server's file changes on the server side
+from read-only back to read-write, reflect this change in default file mode
+(we had been leaving a file's mode read-only until the inode were reloaded).
+Allow setting of attribute back to ATTR_NORMAL (removing readonly dos attribute
+when archive dos attribute not set and we are changing mode back to writeable
+on server which does not support the Unix Extensions). Remove read only dos
+attribute on chmod when adding any write permission (ie on any of
+user/group/other (not all of user/group/other ie 0222) when
+mounted to windows. Add support for POSIX MkDir (slight performance
+enhancement and eliminates the network race between the mkdir and set
+path info of the mode).
+
+
+Version 1.47
+------------
+Fix oops in list_del during mount caused by unaligned string.
+Fix file corruption which could occur on some large file
+copies caused by writepages page i/o completion bug.
+Seek to SEEK_END forces check for update of file size for non-cached
+files. Allow file size to be updated on remote extend of locally open,
+non-cached file. Fix reconnect to newer Samba servers (or other servers
+which support the CIFS Unix/POSIX extensions) so that we again tell the
+server the Unix/POSIX cifs capabilities which we support (SetFSInfo).
+Add experimental support for new POSIX Open/Mkdir (which returns
+stat information on the open, and allows setting the mode).
+
+Version 1.46
+------------
+Support deep tree mounts. Better support OS/2, Win9x (DOS) time stamps.
+Allow null user to be specified on mount ("username="). Do not return
+EINVAL on readdir when filldir fails due to overwritten blocksize
+(fixes FC problem). Return error in rename 2nd attempt retry (ie report
+if rename by handle also fails, after rename by path fails, we were
+not reporting whether the retry worked or not). Fix NTLMv2 to
+work to Windows servers (mount with option "sec=ntlmv2").
+
+Version 1.45
+------------
+Do not time out lockw calls when using posix extensions. Do not
+time out requests if server still responding reasonably fast
+on requests on other threads. Improve POSIX locking emulation,
+(lock cancel now works, and unlock of merged range works even
+to Windows servers now). Fix oops on mount to lanman servers
+(win9x, os/2 etc.) when null password. Do not send listxattr
+(SMB to query all EAs) if nouser_xattr specified. Fix SE Linux
+problem (instantiate inodes/dentries in right order for readdir).
+
+Version 1.44
+------------
+Rewritten sessionsetup support, including support for legacy SMB
+session setup needed for OS/2 and older servers such as Windows 95 and 98.
+Fix oops on ls to OS/2 servers. Add support for level 1 FindFirst
+so we can do search (ls etc.) to OS/2. Do not send NTCreateX
+or recent levels of FindFirst unless server says it supports NT SMBs
+(instead use legacy equivalents from LANMAN dialect). Fix to allow
+NTLMv2 authentication support (now can use stronger password hashing
+on mount if corresponding /proc/fs/cifs/SecurityFlags is set (0x4004).
+Allow override of global cifs security flags on mount via "sec=" option(s).
+
+Version 1.43
+------------
+POSIX locking to servers which support CIFS POSIX Extensions
+(disabled by default controlled by proc/fs/cifs/Experimental).
+Handle conversion of long share names (especially Asian languages)
+to Unicode during mount. Fix memory leak in sess struct on reconnect.
+Fix rare oops after acpi suspend. Fix O_TRUNC opens to overwrite on
+cifs open which helps rare case when setpathinfo fails or server does
+not support it.
+
+Version 1.42
+------------
+Fix slow oplock break when mounted to different servers at the same time and
+the tids match and we try to find matching fid on wrong server. Fix read
+looping when signing required by server (2.6.16 kernel only). Fix readdir
+vs. rename race which could cause each to hang. Return . and .. even
+if server does not. Allow searches to skip first three entries and
+begin at any location. Fix oops in find_writeable_file.
+
+Version 1.41
+------------
+Fix NTLMv2 security (can be enabled in /proc/fs/cifs) so customers can
+configure stronger authentication. Fix sfu symlinks so they can
+be followed (not just recognized). Fix wraparound of bcc on
+read responses when buffer size over 64K and also fix wrap of
+max smb buffer size when CIFSMaxBufSize over 64K. Fix oops in
+cifs_user_read and cifs_readpages (when EAGAIN on send of smb
+on socket is returned over and over). Add POSIX (advisory) byte range
+locking support (requires server with newest CIFS UNIX Extensions
+to the protocol implemented). Slow down negprot slightly in port 139
+RFC1001 case to give session_init time on buggy servers.
+
+Version 1.40
+------------
+Use fsuid (fsgid) more consistently instead of uid (gid). Improve performance
+of readpages by eliminating one extra memcpy. Allow update of file size
+from remote server even if file is open for write as long as mount is
+directio. Recognize share mode security and send NTLM encrypted password
+on tree connect if share mode negotiated.
+
+Version 1.39
+------------
+Defer close of a file handle slightly if pending writes depend on that handle
+(this reduces the EBADF bad file handle errors that can be logged under heavy
+stress on writes). Modify cifs Kconfig options to expose CONFIG_CIFS_STATS2
+Fix SFU style symlinks and mknod needed for servers which do not support the
+CIFS Unix Extensions. Fix setfacl/getfacl on bigendian. Timeout negative
+dentries so files that the client sees as deleted but that later get created
+on the server will be recognized. Add client side permission check on setattr.
+Timeout stuck requests better (where server has never responded or sent corrupt
+responses)
+
+Version 1.38
+------------
+Fix tcp socket retransmission timeouts (e.g. on ENOSPACE from the socket)
+to be smaller at first (but increasing) so large write performance performance
+over GigE is better. Do not hang thread on illegal byte range lock response
+from Windows (Windows can send an RFC1001 size which does not match smb size) by
+allowing an SMBs TCP length to be up to a few bytes longer than it should be.
+wsize and rsize can now be larger than negotiated buffer size if server
+supports large readx/writex, even when directio mount flag not specified.
+Write size will in many cases now be 16K instead of 4K which greatly helps
+file copy performance on lightly loaded networks. Fix oops in dnotify
+when experimental config flag enabled. Make cifsFYI more granular.
+
+Version 1.37
+------------
+Fix readdir caching when unlink removes file in current search buffer,
+and this is followed by a rewind search to just before the deleted entry.
+Do not attempt to set ctime unless atime and/or mtime change requested
+(most servers throw it away anyway). Fix length check of received smbs
+to be more accurate. Fix big endian problem with mapchars mount option,
+and with a field returned by statfs.
+
+Version 1.36
+------------
+Add support for mounting to older pre-CIFS servers such as Windows9x and ME.
+For these older servers, add option for passing netbios name of server in
+on mount (servernetbiosname). Add suspend support for power management, to
+avoid cifsd thread preventing software suspend from working.
+Add mount option for disabling the default behavior of sending byte range lock
+requests to the server (necessary for certain applications which break with
+mandatory lock behavior such as Evolution), and also mount option for
+requesting case insensitive matching for path based requests (requesting
+case sensitive is the default).
+
+Version 1.35
+------------
+Add writepage performance improvements. Fix path name conversions
+for long filenames on mounts which were done with "mapchars" mount option
+specified. Ensure multiplex ids do not collide. Fix case in which
+rmmod can oops if done soon after last unmount. Fix truncated
+search (readdir) output when resume filename was a long filename.
+Fix filename conversion when mapchars mount option was specified and
+filename was a long filename.
+
+Version 1.34
+------------
+Fix error mapping of the TOO_MANY_LINKS (hardlinks) case.
+Do not oops if root user kills cifs oplock kernel thread or
+kills the cifsd thread (NB: killing the cifs kernel threads is not
+recommended, unmount and rmmod cifs will kill them when they are
+no longer needed). Fix readdir to ASCII servers (ie older servers
+which do not support Unicode) and also require asterisk.
+Fix out of memory case in which data could be written one page
+off in the page cache.
+
+Version 1.33
+------------
+Fix caching problem, in which readdir of directory containing a file
+which was cached could cause the file's time stamp to be updated
+without invalidating the readahead data (so we could get stale
+file data on the client for that file even as the server copy changed).
+Cleanup response processing so cifsd can not loop when abnormally
+terminated.
+
+
+Version 1.32
+------------
+Fix oops in ls when Transact2 FindFirst (or FindNext) returns more than one
+transact response for an SMB request and search entry split across two frames.
+Add support for lsattr (getting ext2/ext3/reiserfs attr flags from the server)
+as new protocol extensions. Do not send Get/Set calls for POSIX ACLs
+unless server explicitly claims to support them in CIFS Unix extensions
+POSIX ACL capability bit. Fix packet signing when multiuser mounting with
+different users from the same client to the same server. Fix oops in
+cifs_close. Add mount option for remapping reserved characters in
+filenames (also allow recognizing files with created by SFU which have any
+of these seven reserved characters, except backslash, to be recognized).
+Fix invalid transact2 message (we were sometimes trying to interpret
+oplock breaks as SMB responses). Add ioctl for checking that the
+current uid matches the uid of the mounter (needed by umount.cifs).
+Reduce the number of large buffer allocations in cifs response processing
+(significantly reduces memory pressure under heavy stress with multiple
+processes accessing the same server at the same time).
+
+Version 1.31
+------------
+Fix updates of DOS attributes and time fields so that files on NT4 servers
+do not get marked delete on close. Display sizes of cifs buffer pools in
+cifs stats. Fix oops in unmount when cifsd thread being killed by
+shutdown. Add generic readv/writev and aio support. Report inode numbers
+consistently in readdir and lookup (when serverino mount option is
+specified use the inode number that the server reports - for both lookup
+and readdir, otherwise by default the locally generated inode number is used
+for inodes created in either path since servers are not always able to
+provide unique inode numbers when exporting multiple volumes from under one
+sharename).
+
+Version 1.30
+------------
+Allow new nouser_xattr mount parm to disable xattr support for user namespace.
+Do not flag user_xattr mount parm in dmesg. Retry failures setting file time
+(mostly affects NT4 servers) by retry with handle based network operation.
+Add new POSIX Query FS Info for returning statfs info more accurately.
+Handle passwords with multiple commas in them.
+
+Version 1.29
+------------
+Fix default mode in sysfs of cifs module parms. Remove old readdir routine.
+Fix capabilities flags for large readx so as to allow reads larger than 64K.
+
+Version 1.28
+------------
+Add module init parm for large SMB buffer size (to allow it to be changed
+from its default of 16K) which is especially useful for large file copy
+when mounting with the directio mount option. Fix oops after
+returning from mount when experimental ExtendedSecurity enabled and
+SpnegoNegotiated returning invalid error. Fix case to retry better when
+peek returns from 1 to 3 bytes on socket which should have more data.
+Fixed path based calls (such as cifs lookup) to handle path names
+longer than 530 (now can handle PATH_MAX). Fix pass through authentication
+from Samba server to DC (Samba required dummy LM password).
+
+Version 1.27
+------------
+Turn off DNOTIFY (directory change notification support) by default
+(unless built with the experimental flag) to fix hang with KDE
+file browser. Fix DNOTIFY flag mappings. Fix hang (in wait_event
+waiting on an SMB response) in SendReceive when session dies but
+reconnects quickly from another task. Add module init parms for
+minimum number of large and small network buffers in the buffer pools,
+and for the maximum number of simultaneous requests.
+
+Version 1.26
+------------
+Add setfacl support to allow setting of ACLs remotely to Samba 3.10 and later
+and other POSIX CIFS compliant servers. Fix error mapping for getfacl
+to EOPNOTSUPP when server does not support posix acls on the wire. Fix
+improperly zeroed buffer in CIFS Unix extensions set times call.
+
+Version 1.25
+------------
+Fix internationalization problem in cifs readdir with filenames that map to
+longer UTF-8 strings than the string on the wire was in Unicode. Add workaround
+for readdir to netapp servers. Fix search rewind (seek into readdir to return
+non-consecutive entries). Do not do readdir when server negotiates
+buffer size to small to fit filename. Add support for reading POSIX ACLs from
+the server (add also acl and noacl mount options).
+
+Version 1.24
+------------
+Optionally allow using server side inode numbers, rather than client generated
+ones by specifying mount option "serverino" - this is required for some apps
+to work which double check hardlinked files and have persistent inode numbers.
+
+Version 1.23
+------------
+Multiple bigendian fixes. On little endian systems (for reconnect after
+network failure) fix tcp session reconnect code so we do not try first
+to reconnect on reverse of port 445. Treat reparse points (NTFS junctions)
+as directories rather than symlinks because we can do follow link on them.
+
+Version 1.22
+------------
+Add config option to enable XATTR (extended attribute) support, mapping
+xattr names in the "user." namespace space to SMB/CIFS EAs. Lots of
+minor fixes pointed out by the Stanford SWAT checker (mostly missing
+or out of order NULL pointer checks in little used error paths).
+
+Version 1.21
+------------
+Add new mount parm to control whether mode check (generic_permission) is done
+on the client. If Unix extensions are enabled and the uids on the client
+and server do not match, client permission checks are meaningless on
+server uids that do not exist on the client (this does not affect the
+normal ACL check which occurs on the server). Fix default uid
+on mknod to match create and mkdir. Add optional mount parm to allow
+override of the default uid behavior (in which the server sets the uid
+and gid of newly created files). Normally for network filesystem mounts
+user want the server to set the uid/gid on newly created files (rather than
+using uid of the client processes you would in a local filesystem).
+
+Version 1.20
+------------
+Make transaction counts more consistent. Merge /proc/fs/cifs/SimultaneousOps
+info into /proc/fs/cifs/DebugData. Fix oops in rare oops in readdir
+(in build_wildcard_path_from_dentry). Fix mknod to pass type field
+(block/char/fifo) properly. Remove spurious mount warning log entry when
+credentials passed as mount argument. Set major/minor device number in
+inode for block and char devices when unix extensions enabled.
+
+Version 1.19
+------------
+Fix /proc/fs/cifs/Stats and DebugData display to handle larger
+amounts of return data. Properly limit requests to MAX_REQ (50
+is the usual maximum active multiplex SMB/CIFS requests per server).
+Do not kill cifsd (and thus hurt the other SMB session) when more than one
+session to the same server (but with different userids) exists and one
+of the two user's smb sessions is being removed while leaving the other.
+Do not loop reconnecting in cifsd demultiplex thread when admin
+kills the thread without going through unmount.
+
+Version 1.18
+------------
+Do not rename hardlinked files (since that should be a noop). Flush
+cached write behind data when reopening a file after session abend,
+except when already in write. Grab per socket sem during reconnect
+to avoid oops in sendmsg if overlapping with reconnect. Do not
+reset cached inode file size on readdir for files open for write on
+client.
+
+
+Version 1.17
+------------
+Update number of blocks in file so du command is happier (in Linux a fake
+blocksize of 512 is required for calculating number of blocks in inode).
+Fix prepare write of partial pages to read in data from server if possible.
+Fix race on tcpStatus field between unmount and reconnection code, causing
+cifsd process sometimes to hang around forever. Improve out of memory
+checks in cifs_filldir
+
+Version 1.16
+------------
+Fix incorrect file size in file handle based setattr on big endian hardware.
+Fix oops in build_path_from_dentry when out of memory. Add checks for invalid
+and closing file structs in writepage/partialpagewrite. Add statistics
+for each mounted share (new menuconfig option). Fix endianness problem in
+volume information displayed in /proc/fs/cifs/DebugData (only affects
+affects big endian architectures). Prevent renames while constructing
+path names for open, mkdir and rmdir.
+
+Version 1.15
+------------
+Change to mempools for alloc smb request buffers and multiplex structs
+to better handle low memory problems (and potential deadlocks).
+
+Version 1.14
+------------
+Fix incomplete listings of large directories on Samba servers when Unix
+extensions enabled. Fix oops when smb_buffer can not be allocated. Fix
+rename deadlock when writing out dirty pages at same time.
+
+Version 1.13
+------------
+Fix open of files in which O_CREATE can cause the mode to change in
+some cases. Fix case in which retry of write overlaps file close.
+Fix PPC64 build error. Reduce excessive stack usage in smb password
+hashing. Fix overwrite of Linux user's view of file mode to Windows servers.
+
+Version 1.12
+------------
+Fixes for large file copy, signal handling, socket retry, buffer
+allocation and low memory situations.
+
+Version 1.11
+------------
+Better port 139 support to Windows servers (RFC1001/RFC1002 Session_Initialize)
+also now allowing support for specifying client netbiosname. NT4 support added.
+
+Version 1.10
+------------
+Fix reconnection (and certain failed mounts) to properly wake up the
+blocked users thread so it does not seem hung (in some cases was blocked
+until the cifs receive timeout expired). Fix spurious error logging
+to kernel log when application with open network files killed.
+
+Version 1.09
+------------
+Fix /proc/fs module unload warning message (that could be logged
+to the kernel log). Fix intermittent failure in connectathon
+test7 (hardlink count not immediately refreshed in case in which
+inode metadata can be incorrectly kept cached when time near zero)
+
+Version 1.08
+------------
+Allow file_mode and dir_mode (specified at mount time) to be enforced
+locally (the server already enforced its own ACLs too) for servers
+that do not report the correct mode (do not support the
+CIFS Unix Extensions).
+
+Version 1.07
+------------
+Fix some small memory leaks in some unmount error paths. Fix major leak
+of cache pages in readpages causing multiple read oriented stress
+testcases (including fsx, and even large file copy) to fail over time.
+
+Version 1.06
+------------
+Send NTCreateX with ATTR_POSIX if Linux/Unix extensions negotiated with server.
+This allows files that differ only in case and improves performance of file
+creation and file open to such servers. Fix semaphore conflict which causes
+slow delete of open file to Samba (which unfortunately can cause an oplock
+break to self while vfs_unlink held i_sem) which can hang for 20 seconds.
+
+Version 1.05
+------------
+fixes to cifs_readpages for fsx test case
+
+Version 1.04
+------------
+Fix caching data integrity bug when extending file size especially when no
+oplock on file. Fix spurious logging of valid already parsed mount options
+that are parsed outside of the cifs vfs such as nosuid.
+
+
+Version 1.03
+------------
+Connect to server when port number override not specified, and tcp port
+unitialized. Reset search to restart at correct file when kernel routine
+filldir returns error during large directory searches (readdir).
+
+Version 1.02
+------------
+Fix caching problem when files opened by multiple clients in which
+page cache could contain stale data, and write through did
+not occur often enough while file was still open when read ahead
+(read oplock) not allowed. Treat "sep=" when first mount option
+as an override of comma as the default separator between mount
+options.
+
+Version 1.01
+------------
+Allow passwords longer than 16 bytes. Allow null password string.
+
+Version 1.00
+------------
+Gracefully clean up failed mounts when attempting to mount to servers such as
+Windows 98 that terminate tcp sessions during protocol negotiation. Handle
+embedded commas in mount parsing of passwords.
+
+Version 0.99
+------------
+Invalidate local inode cached pages on oplock break and when last file
+instance is closed so that the client does not continue using stale local
+copy rather than later modified server copy of file. Do not reconnect
+when server drops the tcp session prematurely before negotiate
+protocol response. Fix oops in reopen_file when dentry freed. Allow
+the support for CIFS Unix Extensions to be disabled via proc interface.
+
+Version 0.98
+------------
+Fix hang in commit_write during reconnection of open files under heavy load.
+Fix unload_nls oops in a mount failure path. Serialize writes to same socket
+which also fixes any possible races when cifs signatures are enabled in SMBs
+being sent out of signature sequence number order.
+
+Version 0.97
+------------
+Fix byte range locking bug (endian problem) causing bad offset and
+length.
+
+Version 0.96
+------------
+Fix oops (in send_sig) caused by CIFS unmount code trying to
+wake up the demultiplex thread after it had exited. Do not log
+error on harmless oplock release of closed handle.
+
+Version 0.95
+------------
+Fix unsafe global variable usage and password hash failure on gcc 3.3.1
+Fix problem reconnecting secondary mounts to same server after session
+failure. Fix invalid dentry - race in mkdir when directory gets created
+by another client between the lookup and mkdir.
+
+Version 0.94
+------------
+Fix to list processing in reopen_files. Fix reconnection when server hung
+but tcpip session still alive. Set proper timeout on socket read.
+
+Version 0.93
+------------
+Add missing mount options including iocharset. SMP fixes in write and open.
+Fix errors in reconnecting after TCP session failure. Fix module unloading
+of default nls codepage
+
+Version 0.92
+------------
+Active smb transactions should never go negative (fix double FreeXid). Fix
+list processing in file routines. Check return code on kmalloc in open.
+Fix spinlock usage for SMP.
+
+Version 0.91
+------------
+Fix oops in reopen_files when invalid dentry. drop dentry on server rename
+and on revalidate errors. Fix cases where pid is now tgid. Fix return code
+on create hard link when server does not support them.
+
+Version 0.90
+------------
+Fix scheduling while atomic error in getting inode info on newly created file.
+Fix truncate of existing files opened with O_CREAT but not O_TRUNC set.
+
+Version 0.89
+------------
+Fix oops on write to dead tcp session. Remove error log write for case when file open
+O_CREAT but not O_EXCL
+
+Version 0.88
+------------
+Fix non-POSIX behavior on rename of open file and delete of open file by taking
+advantage of trans2 SetFileInfo rename facility if available on target server.
+Retry on ENOSPC and EAGAIN socket errors.
+
+Version 0.87
+------------
+Fix oops on big endian readdir. Set blksize to be even power of two (2**blkbits) to fix
+allocation size miscalculation. After oplock token lost do not read through
+cache.
+
+Version 0.86
+------------
+Fix oops on empty file readahead. Fix for file size handling for locally cached files.
+
+Version 0.85
+------------
+Fix oops in mkdir when server fails to return inode info. Fix oops in reopen_files
+during auto reconnection to server after server recovered from failure.
+
+Version 0.84
+------------
+Finish support for Linux 2.5 open/create changes, which removes the
+redundant NTCreate/QPathInfo/close that was sent during file create.
+Enable oplock by default. Enable packet signing by default (needed to
+access many recent Windows servers)
+
+Version 0.83
+------------
+Fix oops when mounting to long server names caused by inverted parms to kmalloc.
+Fix MultiuserMount (/proc/fs/cifs configuration setting) so that when enabled
+we will choose a cifs user session (smb uid) that better matches the local
+uid if a) the mount uid does not match the current uid and b) we have another
+session to the same server (ip address) for a different mount which
+matches the current local uid.
+
+Version 0.82
+------------
+Add support for mknod of block or character devices. Fix oplock
+code (distributed caching) to properly send response to oplock
+break from server.
+
+Version 0.81
+------------
+Finish up CIFS packet digital signing for the default
+NTLM security case. This should help Windows 2003
+network interoperability since it is common for
+packet signing to be required now. Fix statfs (stat -f)
+which recently started returning errors due to
+invalid value (-1 instead of 0) being set in the
+struct kstatfs f_ffiles field.
+
+Version 0.80
+-----------
+Fix oops on stopping oplock thread when removing cifs when
+built as module.
+
+Version 0.79
+------------
+Fix mount options for ro (readonly), uid, gid and file and directory mode.
+
+Version 0.78
+------------
+Fix errors displayed on failed mounts to be more understandable.
+Fixed various incorrect or misleading smb to posix error code mappings.
+
+Version 0.77
+------------
+Fix display of NTFS DFS junctions to display as symlinks.
+They are the network equivalent. Fix oops in
+cifs_partialpagewrite caused by missing spinlock protection
+of openfile linked list. Allow writebehind caching errors to
+be returned to the application at file close.
+
+Version 0.76
+------------
+Clean up options displayed in /proc/mounts by show_options to
+be more consistent with other filesystems.
+
+Version 0.75
+------------
+Fix delete of readonly file to Windows servers. Reflect
+presence or absence of read only dos attribute in mode
+bits for servers that do not support CIFS Unix extensions.
+Fix shortened results on readdir of large directories to
+servers supporting CIFS Unix extensions (caused by
+incorrect resume key).
+
+Version 0.74
+------------
+Fix truncate bug (set file size) that could cause hangs e.g. running fsx
+
+Version 0.73
+------------
+unload nls if mount fails.
+
+Version 0.72
+------------
+Add resume key support to search (readdir) code to workaround
+Windows bug. Add /proc/fs/cifs/LookupCacheEnable which
+allows disabling caching of attribute information for
+lookups.
+
+Version 0.71
+------------
+Add more oplock handling (distributed caching code). Remove
+dead code. Remove excessive stack space utilization from
+symlink routines.
+
+Version 0.70
+------------
+Fix oops in get dfs referral (triggered when null path sent in to
+mount). Add support for overriding rsize at mount time.
+
+Version 0.69
+------------
+Fix buffer overrun in readdir which caused intermittent kernel oopses.
+Fix writepage code to release kmap on write data. Allow "-ip=" new
+mount option to be passed in on parameter distinct from the first part
+(server name portion of) the UNC name. Allow override of the
+tcp port of the target server via new mount option "-port="
+
+Version 0.68
+------------
+Fix search handle leak on rewind. Fix setuid and gid so that they are
+reflected in the local inode immediately. Cleanup of whitespace
+to make 2.4 and 2.5 versions more consistent.
+
+
+Version 0.67
+------------
+Fix signal sending so that captive thread (cifsd) exits on umount
+(which was causing the warning in kmem_cache_free of the request buffers
+at rmmod time). This had broken as a sideeffect of the recent global
+kernel change to daemonize. Fix memory leak in readdir code which
+showed up in "ls -R" (and applications that did search rewinding).
+
+Version 0.66
+------------
+Reconnect tids and fids after session reconnection (still do not
+reconnect byte range locks though). Fix problem caching
+lookup information for directory inodes, improving performance,
+especially in deep directory trees. Fix various build warnings.
+
+Version 0.65
+------------
+Finish fixes to commit write for caching/readahead consistency. fsx
+now works to Samba servers. Fix oops caused when readahead
+was interrupted by a signal.
+
+Version 0.64
+------------
+Fix data corruption (in partial page after truncate) that caused fsx to
+fail to Windows servers. Cleaned up some extraneous error logging in
+common error paths. Add generic sendfile support.
+
+Version 0.63
+------------
+Fix memory leak in AllocMidQEntry.
+Finish reconnection logic, so connection with server can be dropped
+(or server rebooted) and the cifs client will reconnect.
+
+Version 0.62
+------------
+Fix temporary socket leak when bad userid or password specified
+(or other SMBSessSetup failure). Increase maximum buffer size to slightly
+over 16K to allow negotiation of up to Samba and Windows server default read
+sizes. Add support for readpages
+
+Version 0.61
+------------
+Fix oops when username not passed in on mount. Extensive fixes and improvements
+to error logging (strip redundant newlines, change debug macros to ensure newline
+passed in and to be more consistent). Fix writepage wrong file handle problem,
+a readonly file handle could be incorrectly used to attempt to write out
+file updates through the page cache to multiply open files. This could cause
+the iozone benchmark to fail on the fwrite test. Fix bug mounting two different
+shares to the same Windows server when using different usernames
+(doing this to Samba servers worked but Windows was rejecting it) - now it is
+possible to use different userids when connecting to the same server from a
+Linux client. Fix oops when treeDisconnect called during unmount on
+previously freed socket.
+
+Version 0.60
+------------
+Fix oops in readpages caused by not setting address space operations in inode in
+rare code path.
+
+Version 0.59
+------------
+Includes support for deleting of open files and renaming over existing files (per POSIX
+requirement). Add readlink support for Windows junction points (directory symlinks).
+
+Version 0.58
+------------
+Changed read and write to go through pagecache. Added additional address space operations.
+Memory mapped operations now working.
+
+Version 0.57
+------------
+Added writepage code for additional memory mapping support. Fixed leak in xids causing
+the simultaneous operations counter (/proc/fs/cifs/SimultaneousOps) to increase on
+every stat call. Additional formatting cleanup.
+
+Version 0.56
+------------
+Fix bigendian bug in order of time conversion. Merge 2.5 to 2.4 version. Formatting cleanup.
+
+Version 0.55
+------------
+Fixes from Zwane Mwaikambo for adding missing return code checking in a few places.
+Also included a modified version of his fix to protect global list manipulation of
+the smb session and tree connection and mid related global variables.
+
+Version 0.54
+------------
+Fix problem with captive thread hanging around at unmount time. Adjust to 2.5.42-pre
+changes to superblock layout. Remove wasteful allocation of smb buffers (now the send
+buffer is reused for responses). Add more oplock handling. Additional minor cleanup.
+
+Version 0.53
+------------
+More stylistic updates to better match kernel style. Add additional statistics
+for filesystem which can be viewed via /proc/fs/cifs. Add more pieces of NTLMv2
+and CIFS Packet Signing enablement.
+
+Version 0.52
+------------
+Replace call to sleep_on with safer wait_on_event.
+Make stylistic changes to better match kernel style recommendations.
+Remove most typedef usage (except for the PDUs themselves).
+
+Version 0.51
+------------
+Update mount so the -unc mount option is no longer required (the ip address can be specified
+in a UNC style device name. Implementation of readpage/writepage started.
+
+Version 0.50
+------------
+Fix intermittent problem with incorrect smb header checking on badly
+fragmented tcp responses
+
+Version 0.49
+------------
+Fixes to setting of allocation size and file size.
+
+Version 0.48
+------------
+Various 2.5.38 fixes. Now works on 2.5.38
+
+Version 0.47
+------------
+Prepare for 2.5 kernel merge. Remove ifdefs.
+
+Version 0.46
+------------
+Socket buffer management fixes. Fix dual free.
+
+Version 0.45
+------------
+Various big endian fixes for hardlinks and symlinks and also for dfs.
+
+Version 0.44
+------------
+Various big endian fixes for servers with Unix extensions such as Samba
+
+Version 0.43
+------------
+Various FindNext fixes for incorrect filenames on large directory searches on big endian
+clients. basic posix file i/o tests now work on big endian machines, not just le
+
+Version 0.42
+------------
+SessionSetup and NegotiateProtocol now work from Big Endian machines.
+Various Big Endian fixes found during testing on the Linux on 390. Various fixes for compatibility with older
+versions of 2.4 kernel (now builds and works again on kernels at least as early as 2.4.7).
+
+Version 0.41
+------------
+Various minor fixes for Connectathon Posix "basic" file i/o test suite. Directory caching fixed so hardlinked
+files now return the correct number of links on fstat as they are repeatedly linked and unlinked.
+
+Version 0.40
+------------
+Implemented "Raw" (i.e. not encapsulated in SPNEGO) NTLMSSP (i.e. the Security Provider Interface used to negotiate
+session advanced session authentication). Raw NTLMSSP is preferred by Windows 2000 Professional and Windows XP.
+Began implementing support for SPNEGO encapsulation of NTLMSSP based session authentication blobs
+(which is the mechanism preferred by Windows 2000 server in the absence of Kerberos).
+
+Version 0.38
+------------
+Introduced optional mount helper utility mount.cifs and made coreq changes to cifs vfs to enable
+it. Fixed a few bugs in the DFS code (e.g. bcc two bytes too short and incorrect uid in PDU).
+
+Version 0.37
+------------
+Rewrote much of connection and mount/unmount logic to handle bugs with
+multiple uses to same share, multiple users to same server etc.
+
+Version 0.36
+------------
+Fixed major problem with dentry corruption (missing call to dput)
+
+Version 0.35
+------------
+Rewrite of readdir code to fix bug. Various fixes for bigendian machines.
+Begin adding oplock support. Multiusermount and oplockEnabled flags added to /proc/fs/cifs
+although corresponding function not fully implemented in the vfs yet
+
+Version 0.34
+------------
+Fixed dentry caching bug, misc. cleanup
+
+Version 0.33
+------------
+Fixed 2.5 support to handle build and configure changes as well as misc. 2.5 changes. Now can build
+on current 2.5 beta version (2.5.24) of the Linux kernel as well as on 2.4 Linux kernels.
+Support for STATUS codes (newer 32 bit NT error codes) added. DFS support begun to be added.
+
+Version 0.32
+------------
+Unix extensions (symlink, readlink, hardlink, chmod and some chgrp and chown) implemented
+and tested against Samba 2.2.5
+
+
+Version 0.31
+------------
+1) Fixed lockrange to be correct (it was one byte too short)
+
+2) Fixed GETLK (i.e. the fcntl call to test a range of bytes in a file to see if locked) to correctly
+show range as locked when there is a conflict with an existing lock.
+
+3) default file perms are now 2767 (indicating support for mandatory locks) instead of 777 for directories
+in most cases. Eventually will offer optional ability to query server for the correct perms.
+
+3) Fixed eventual trap when mounting twice to different shares on the same server when the first succeeded
+but the second one was invalid and failed (the second one was incorrectly disconnecting the tcp and smb
+session)
+
+4) Fixed error logging of valid mount options
+
+5) Removed logging of password field.
+
+6) Moved negotiate, treeDisconnect and uloggoffX (only tConx and SessSetup remain in connect.c) to cifssmb.c
+and cleaned them up and made them more consistent with other cifs functions.
+
+7) Server support for Unix extensions is now fully detected and FindFirst is implemented both ways
+(with or without Unix extensions) but FindNext and QueryPathInfo with the Unix extensions are not completed,
+nor is the symlink support using the Unix extensions
+
+8) Started adding the readlink and follow_link code
+
+Version 0.3
+-----------
+Initial drop
+
diff --git a/Documentation/filesystems/cifs/README b/Documentation/filesystems/cifs/README
new file mode 100644
index 0000000..2d5622f
--- /dev/null
+++ b/Documentation/filesystems/cifs/README
@@ -0,0 +1,753 @@
+The CIFS VFS support for Linux supports many advanced network filesystem
+features such as hierarchical dfs like namespace, hardlinks, locking and more.
+It was designed to comply with the SNIA CIFS Technical Reference (which
+supersedes the 1992 X/Open SMB Standard) as well as to perform best practice
+practical interoperability with Windows 2000, Windows XP, Samba and equivalent
+servers. This code was developed in participation with the Protocol Freedom
+Information Foundation.
+
+Please see
+ http://protocolfreedom.org/ and
+ http://samba.org/samba/PFIF/
+for more details.
+
+
+For questions or bug reports please contact:
+ sfrench@samba.org (sfrench@us.ibm.com)
+
+Build instructions:
+==================
+For Linux 2.4:
+1) Get the kernel source (e.g.from http://www.kernel.org)
+and download the cifs vfs source (see the project page
+at http://us1.samba.org/samba/Linux_CIFS_client.html)
+and change directory into the top of the kernel directory
+then patch the kernel (e.g. "patch -p1 < cifs_24.patch")
+to add the cifs vfs to your kernel configure options if
+it has not already been added (e.g. current SuSE and UL
+users do not need to apply the cifs_24.patch since the cifs vfs is
+already in the kernel configure menu) and then
+mkdir linux/fs/cifs and then copy the current cifs vfs files from
+the cifs download to your kernel build directory e.g.
+
+ cp <cifs_download_dir>/fs/cifs/* to <kernel_download_dir>/fs/cifs
+
+2) make menuconfig (or make xconfig)
+3) select cifs from within the network filesystem choices
+4) save and exit
+5) make dep
+6) make modules (or "make" if CIFS VFS not to be built as a module)
+
+For Linux 2.6:
+1) Download the kernel (e.g. from http://www.kernel.org)
+and change directory into the top of the kernel directory tree
+(e.g. /usr/src/linux-2.5.73)
+2) make menuconfig (or make xconfig)
+3) select cifs from within the network filesystem choices
+4) save and exit
+5) make
+
+
+Installation instructions:
+=========================
+If you have built the CIFS vfs as module (successfully) simply
+type "make modules_install" (or if you prefer, manually copy the file to
+the modules directory e.g. /lib/modules/2.4.10-4GB/kernel/fs/cifs/cifs.o).
+
+If you have built the CIFS vfs into the kernel itself, follow the instructions
+for your distribution on how to install a new kernel (usually you
+would simply type "make install").
+
+If you do not have the utility mount.cifs (in the Samba 3.0 source tree and on
+the CIFS VFS web site) copy it to the same directory in which mount.smbfs and
+similar files reside (usually /sbin). Although the helper software is not
+required, mount.cifs is recommended. Eventually the Samba 3.0 utility program
+"net" may also be helpful since it may someday provide easier mount syntax for
+users who are used to Windows e.g.
+ net use <mount point> <UNC name or cifs URL>
+Note that running the Winbind pam/nss module (logon service) on all of your
+Linux clients is useful in mapping Uids and Gids consistently across the
+domain to the proper network user. The mount.cifs mount helper can be
+trivially built from Samba 3.0 or later source e.g. by executing:
+
+ gcc samba/source/client/mount.cifs.c -o mount.cifs
+
+If cifs is built as a module, then the size and number of network buffers
+and maximum number of simultaneous requests to one server can be configured.
+Changing these from their defaults is not recommended. By executing modinfo
+ modinfo kernel/fs/cifs/cifs.ko
+on kernel/fs/cifs/cifs.ko the list of configuration changes that can be made
+at module initialization time (by running insmod cifs.ko) can be seen.
+
+Allowing User Mounts
+====================
+To permit users to mount and unmount over directories they own is possible
+with the cifs vfs. A way to enable such mounting is to mark the mount.cifs
+utility as suid (e.g. "chmod +s /sbin/mount.cifs). To enable users to
+umount shares they mount requires
+1) mount.cifs version 1.4 or later
+2) an entry for the share in /etc/fstab indicating that a user may
+unmount it e.g.
+//server/usersharename /mnt/username cifs user 0 0
+
+Note that when the mount.cifs utility is run suid (allowing user mounts),
+in order to reduce risks, the "nosuid" mount flag is passed in on mount to
+disallow execution of an suid program mounted on the remote target.
+When mount is executed as root, nosuid is not passed in by default,
+and execution of suid programs on the remote target would be enabled
+by default. This can be changed, as with nfs and other filesystems,
+by simply specifying "nosuid" among the mount options. For user mounts
+though to be able to pass the suid flag to mount requires rebuilding
+mount.cifs with the following flag:
+
+ gcc samba/source/client/mount.cifs.c -DCIFS_ALLOW_USR_SUID -o mount.cifs
+
+There is a corresponding manual page for cifs mounting in the Samba 3.0 and
+later source tree in docs/manpages/mount.cifs.8
+
+Allowing User Unmounts
+======================
+To permit users to ummount directories that they have user mounted (see above),
+the utility umount.cifs may be used. It may be invoked directly, or if
+umount.cifs is placed in /sbin, umount can invoke the cifs umount helper
+(at least for most versions of the umount utility) for umount of cifs
+mounts, unless umount is invoked with -i (which will avoid invoking a umount
+helper). As with mount.cifs, to enable user unmounts umount.cifs must be marked
+as suid (e.g. "chmod +s /sbin/umount.cifs") or equivalent (some distributions
+allow adding entries to a file to the /etc/permissions file to achieve the
+equivalent suid effect). For this utility to succeed the target path
+must be a cifs mount, and the uid of the current user must match the uid
+of the user who mounted the resource.
+
+Also note that the customary way of allowing user mounts and unmounts is
+(instead of using mount.cifs and unmount.cifs as suid) to add a line
+to the file /etc/fstab for each //server/share you wish to mount, but
+this can become unwieldy when potential mount targets include many
+or unpredictable UNC names.
+
+Samba Considerations
+====================
+To get the maximum benefit from the CIFS VFS, we recommend using a server that
+supports the SNIA CIFS Unix Extensions standard (e.g. Samba 2.2.5 or later or
+Samba 3.0) but the CIFS vfs works fine with a wide variety of CIFS servers.
+Note that uid, gid and file permissions will display default values if you do
+not have a server that supports the Unix extensions for CIFS (such as Samba
+2.2.5 or later). To enable the Unix CIFS Extensions in the Samba server, add
+the line:
+
+ unix extensions = yes
+
+to your smb.conf file on the server. Note that the following smb.conf settings
+are also useful (on the Samba server) when the majority of clients are Unix or
+Linux:
+
+ case sensitive = yes
+ delete readonly = yes
+ ea support = yes
+
+Note that server ea support is required for supporting xattrs from the Linux
+cifs client, and that EA support is present in later versions of Samba (e.g.
+3.0.6 and later (also EA support works in all versions of Windows, at least to
+shares on NTFS filesystems). Extended Attribute (xattr) support is an optional
+feature of most Linux filesystems which may require enabling via
+make menuconfig. Client support for extended attributes (user xattr) can be
+disabled on a per-mount basis by specifying "nouser_xattr" on mount.
+
+The CIFS client can get and set POSIX ACLs (getfacl, setfacl) to Samba servers
+version 3.10 and later. Setting POSIX ACLs requires enabling both XATTR and
+then POSIX support in the CIFS configuration options when building the cifs
+module. POSIX ACL support can be disabled on a per mount basic by specifying
+"noacl" on mount.
+
+Some administrators may want to change Samba's smb.conf "map archive" and
+"create mask" parameters from the default. Unless the create mask is changed
+newly created files can end up with an unnecessarily restrictive default mode,
+which may not be what you want, although if the CIFS Unix extensions are
+enabled on the server and client, subsequent setattr calls (e.g. chmod) can
+fix the mode. Note that creating special devices (mknod) remotely
+may require specifying a mkdev function to Samba if you are not using
+Samba 3.0.6 or later. For more information on these see the manual pages
+("man smb.conf") on the Samba server system. Note that the cifs vfs,
+unlike the smbfs vfs, does not read the smb.conf on the client system
+(the few optional settings are passed in on mount via -o parameters instead).
+Note that Samba 2.2.7 or later includes a fix that allows the CIFS VFS to delete
+open files (required for strict POSIX compliance). Windows Servers already
+supported this feature. Samba server does not allow symlinks that refer to files
+outside of the share, so in Samba versions prior to 3.0.6, most symlinks to
+files with absolute paths (ie beginning with slash) such as:
+ ln -s /mnt/foo bar
+would be forbidden. Samba 3.0.6 server or later includes the ability to create
+such symlinks safely by converting unsafe symlinks (ie symlinks to server
+files that are outside of the share) to a samba specific format on the server
+that is ignored by local server applications and non-cifs clients and that will
+not be traversed by the Samba server). This is opaque to the Linux client
+application using the cifs vfs. Absolute symlinks will work to Samba 3.0.5 or
+later, but only for remote clients using the CIFS Unix extensions, and will
+be invisbile to Windows clients and typically will not affect local
+applications running on the same server as Samba.
+
+Use instructions:
+================
+Once the CIFS VFS support is built into the kernel or installed as a module
+(cifs.o), you can use mount syntax like the following to access Samba or Windows
+servers:
+
+ mount -t cifs //9.53.216.11/e$ /mnt -o user=myname,pass=mypassword
+
+Before -o the option -v may be specified to make the mount.cifs
+mount helper display the mount steps more verbosely.
+After -o the following commonly used cifs vfs specific options
+are supported:
+
+ user=<username>
+ pass=<password>
+ domain=<domain name>
+
+Other cifs mount options are described below. Use of TCP names (in addition to
+ip addresses) is available if the mount helper (mount.cifs) is installed. If
+you do not trust the server to which are mounted, or if you do not have
+cifs signing enabled (and the physical network is insecure), consider use
+of the standard mount options "noexec" and "nosuid" to reduce the risk of
+running an altered binary on your local system (downloaded from a hostile server
+or altered by a hostile router).
+
+Although mounting using format corresponding to the CIFS URL specification is
+not possible in mount.cifs yet, it is possible to use an alternate format
+for the server and sharename (which is somewhat similar to NFS style mount
+syntax) instead of the more widely used UNC format (i.e. \\server\share):
+ mount -t cifs tcp_name_of_server:share_name /mnt -o user=myname,pass=mypasswd
+
+When using the mount helper mount.cifs, passwords may be specified via alternate
+mechanisms, instead of specifying it after -o using the normal "pass=" syntax
+on the command line:
+1) By including it in a credential file. Specify credentials=filename as one
+of the mount options. Credential files contain two lines
+ username=someuser
+ password=your_password
+2) By specifying the password in the PASSWD environment variable (similarly
+the user name can be taken from the USER environment variable).
+3) By specifying the password in a file by name via PASSWD_FILE
+4) By specifying the password in a file by file descriptor via PASSWD_FD
+
+If no password is provided, mount.cifs will prompt for password entry
+
+Restrictions
+============
+Servers must support either "pure-TCP" (port 445 TCP/IP CIFS connections) or RFC
+1001/1002 support for "Netbios-Over-TCP/IP." This is not likely to be a
+problem as most servers support this.
+
+Valid filenames differ between Windows and Linux. Windows typically restricts
+filenames which contain certain reserved characters (e.g.the character :
+which is used to delimit the beginning of a stream name by Windows), while
+Linux allows a slightly wider set of valid characters in filenames. Windows
+servers can remap such characters when an explicit mapping is specified in
+the Server's registry. Samba starting with version 3.10 will allow such
+filenames (ie those which contain valid Linux characters, which normally
+would be forbidden for Windows/CIFS semantics) as long as the server is
+configured for Unix Extensions (and the client has not disabled
+/proc/fs/cifs/LinuxExtensionsEnabled).
+
+
+CIFS VFS Mount Options
+======================
+A partial list of the supported mount options follows:
+ user The user name to use when trying to establish
+ the CIFS session.
+ password The user password. If the mount helper is
+ installed, the user will be prompted for password
+ if not supplied.
+ ip The ip address of the target server
+ unc The target server Universal Network Name (export) to
+ mount.
+ domain Set the SMB/CIFS workgroup name prepended to the
+ username during CIFS session establishment
+ forceuid Set the default uid for inodes to the uid
+ passed in on mount. For mounts to servers
+ which do support the CIFS Unix extensions, such as a
+ properly configured Samba server, the server provides
+ the uid, gid and mode so this parameter should not be
+ specified unless the server and clients uid and gid
+ numbering differ. If the server and client are in the
+ same domain (e.g. running winbind or nss_ldap) and
+ the server supports the Unix Extensions then the uid
+ and gid can be retrieved from the server (and uid
+ and gid would not have to be specifed on the mount.
+ For servers which do not support the CIFS Unix
+ extensions, the default uid (and gid) returned on lookup
+ of existing files will be the uid (gid) of the person
+ who executed the mount (root, except when mount.cifs
+ is configured setuid for user mounts) unless the "uid="
+ (gid) mount option is specified. Also note that permission
+ checks (authorization checks) on accesses to a file occur
+ at the server, but there are cases in which an administrator
+ may want to restrict at the client as well. For those
+ servers which do not report a uid/gid owner
+ (such as Windows), permissions can also be checked at the
+ client, and a crude form of client side permission checking
+ can be enabled by specifying file_mode and dir_mode on
+ the client. (default)
+ forcegid (similar to above but for the groupid instead of uid) (default)
+ noforceuid Fill in file owner information (uid) by requesting it from
+ the server if possible. With this option, the value given in
+ the uid= option (on mount) will only be used if the server
+ can not support returning uids on inodes.
+ noforcegid (similar to above but for the group owner, gid, instead of uid)
+ uid Set the default uid for inodes, and indicate to the
+ cifs kernel driver which local user mounted. If the server
+ supports the unix extensions the default uid is
+ not used to fill in the owner fields of inodes (files)
+ unless the "forceuid" parameter is specified.
+ gid Set the default gid for inodes (similar to above).
+ file_mode If CIFS Unix extensions are not supported by the server
+ this overrides the default mode for file inodes.
+ fsc Enable local disk caching using FS-Cache (off by default). This
+ option could be useful to improve performance on a slow link,
+ heavily loaded server and/or network where reading from the
+ disk is faster than reading from the server (over the network).
+ This could also impact scalability positively as the
+ number of calls to the server are reduced. However, local
+ caching is not suitable for all workloads for e.g. read-once
+ type workloads. So, you need to consider carefully your
+ workload/scenario before using this option. Currently, local
+ disk caching is functional for CIFS files opened as read-only.
+ dir_mode If CIFS Unix extensions are not supported by the server
+ this overrides the default mode for directory inodes.
+ port attempt to contact the server on this tcp port, before
+ trying the usual ports (port 445, then 139).
+ iocharset Codepage used to convert local path names to and from
+ Unicode. Unicode is used by default for network path
+ names if the server supports it. If iocharset is
+ not specified then the nls_default specified
+ during the local client kernel build will be used.
+ If server does not support Unicode, this parameter is
+ unused.
+ rsize default read size (usually 16K). The client currently
+ can not use rsize larger than CIFSMaxBufSize. CIFSMaxBufSize
+ defaults to 16K and may be changed (from 8K to the maximum
+ kmalloc size allowed by your kernel) at module install time
+ for cifs.ko. Setting CIFSMaxBufSize to a very large value
+ will cause cifs to use more memory and may reduce performance
+ in some cases. To use rsize greater than 127K (the original
+ cifs protocol maximum) also requires that the server support
+ a new Unix Capability flag (for very large read) which some
+ newer servers (e.g. Samba 3.0.26 or later) do. rsize can be
+ set from a minimum of 2048 to a maximum of 130048 (127K or
+ CIFSMaxBufSize, whichever is smaller)
+ wsize default write size (default 57344)
+ maximum wsize currently allowed by CIFS is 57344 (fourteen
+ 4096 byte pages)
+ actimeo=n attribute cache timeout in seconds (default 1 second).
+ After this timeout, the cifs client requests fresh attribute
+ information from the server. This option allows to tune the
+ attribute cache timeout to suit the workload needs. Shorter
+ timeouts mean better the cache coherency, but increased number
+ of calls to the server. Longer timeouts mean reduced number
+ of calls to the server at the expense of less stricter cache
+ coherency checks (i.e. incorrect attribute cache for a short
+ period of time).
+ rw mount the network share read-write (note that the
+ server may still consider the share read-only)
+ ro mount network share read-only
+ version used to distinguish different versions of the
+ mount helper utility (not typically needed)
+ sep if first mount option (after the -o), overrides
+ the comma as the separator between the mount
+ parms. e.g.
+ -o user=myname,password=mypassword,domain=mydom
+ could be passed instead with period as the separator by
+ -o sep=.user=myname.password=mypassword.domain=mydom
+ this might be useful when comma is contained within username
+ or password or domain. This option is less important
+ when the cifs mount helper cifs.mount (version 1.1 or later)
+ is used.
+ nosuid Do not allow remote executables with the suid bit
+ program to be executed. This is only meaningful for mounts
+ to servers such as Samba which support the CIFS Unix Extensions.
+ If you do not trust the servers in your network (your mount
+ targets) it is recommended that you specify this option for
+ greater security.
+ exec Permit execution of binaries on the mount.
+ noexec Do not permit execution of binaries on the mount.
+ dev Recognize block devices on the remote mount.
+ nodev Do not recognize devices on the remote mount.
+ suid Allow remote files on this mountpoint with suid enabled to
+ be executed (default for mounts when executed as root,
+ nosuid is default for user mounts).
+ credentials Although ignored by the cifs kernel component, it is used by
+ the mount helper, mount.cifs. When mount.cifs is installed it
+ opens and reads the credential file specified in order
+ to obtain the userid and password arguments which are passed to
+ the cifs vfs.
+ guest Although ignored by the kernel component, the mount.cifs
+ mount helper will not prompt the user for a password
+ if guest is specified on the mount options. If no
+ password is specified a null password will be used.
+ perm Client does permission checks (vfs_permission check of uid
+ and gid of the file against the mode and desired operation),
+ Note that this is in addition to the normal ACL check on the
+ target machine done by the server software.
+ Client permission checking is enabled by default.
+ noperm Client does not do permission checks. This can expose
+ files on this mount to access by other users on the local
+ client system. It is typically only needed when the server
+ supports the CIFS Unix Extensions but the UIDs/GIDs on the
+ client and server system do not match closely enough to allow
+ access by the user doing the mount, but it may be useful with
+ non CIFS Unix Extension mounts for cases in which the default
+ mode is specified on the mount but is not to be enforced on the
+ client (e.g. perhaps when MultiUserMount is enabled)
+ Note that this does not affect the normal ACL check on the
+ target machine done by the server software (of the server
+ ACL against the user name provided at mount time).
+ serverino Use server's inode numbers instead of generating automatically
+ incrementing inode numbers on the client. Although this will
+ make it easier to spot hardlinked files (as they will have
+ the same inode numbers) and inode numbers may be persistent,
+ note that the server does not guarantee that the inode numbers
+ are unique if multiple server side mounts are exported under a
+ single share (since inode numbers on the servers might not
+ be unique if multiple filesystems are mounted under the same
+ shared higher level directory). Note that some older
+ (e.g. pre-Windows 2000) do not support returning UniqueIDs
+ or the CIFS Unix Extensions equivalent and for those
+ this mount option will have no effect. Exporting cifs mounts
+ under nfsd requires this mount option on the cifs mount.
+ This is now the default if server supports the
+ required network operation.
+ noserverino Client generates inode numbers (rather than using the actual one
+ from the server). These inode numbers will vary after
+ unmount or reboot which can confuse some applications,
+ but not all server filesystems support unique inode
+ numbers.
+ setuids If the CIFS Unix extensions are negotiated with the server
+ the client will attempt to set the effective uid and gid of
+ the local process on newly created files, directories, and
+ devices (create, mkdir, mknod). If the CIFS Unix Extensions
+ are not negotiated, for newly created files and directories
+ instead of using the default uid and gid specified on
+ the mount, cache the new file's uid and gid locally which means
+ that the uid for the file can change when the inode is
+ reloaded (or the user remounts the share).
+ nosetuids The client will not attempt to set the uid and gid on
+ on newly created files, directories, and devices (create,
+ mkdir, mknod) which will result in the server setting the
+ uid and gid to the default (usually the server uid of the
+ user who mounted the share). Letting the server (rather than
+ the client) set the uid and gid is the default. If the CIFS
+ Unix Extensions are not negotiated then the uid and gid for
+ new files will appear to be the uid (gid) of the mounter or the
+ uid (gid) parameter specified on the mount.
+ netbiosname When mounting to servers via port 139, specifies the RFC1001
+ source name to use to represent the client netbios machine
+ name when doing the RFC1001 netbios session initialize.
+ direct Do not do inode data caching on files opened on this mount.
+ This precludes mmapping files on this mount. In some cases
+ with fast networks and little or no caching benefits on the
+ client (e.g. when the application is doing large sequential
+ reads bigger than page size without rereading the same data)
+ this can provide better performance than the default
+ behavior which caches reads (readahead) and writes
+ (writebehind) through the local Linux client pagecache
+ if oplock (caching token) is granted and held. Note that
+ direct allows write operations larger than page size
+ to be sent to the server.
+ strictcache Use for switching on strict cache mode. In this mode the
+ client read from the cache all the time it has Oplock Level II,
+ otherwise - read from the server. All written data are stored
+ in the cache, but if the client doesn't have Exclusive Oplock,
+ it writes the data to the server.
+ rwpidforward Forward pid of a process who opened a file to any read or write
+ operation on that file. This prevent applications like WINE
+ from failing on read and write if we use mandatory brlock style.
+ acl Allow setfacl and getfacl to manage posix ACLs if server
+ supports them. (default)
+ noacl Do not allow setfacl and getfacl calls on this mount
+ user_xattr Allow getting and setting user xattrs (those attributes whose
+ name begins with "user." or "os2.") as OS/2 EAs (extended
+ attributes) to the server. This allows support of the
+ setfattr and getfattr utilities. (default)
+ nouser_xattr Do not allow getfattr/setfattr to get/set/list xattrs
+ mapchars Translate six of the seven reserved characters (not backslash)
+ *?<>|:
+ to the remap range (above 0xF000), which also
+ allows the CIFS client to recognize files created with
+ such characters by Windows's POSIX emulation. This can
+ also be useful when mounting to most versions of Samba
+ (which also forbids creating and opening files
+ whose names contain any of these seven characters).
+ This has no effect if the server does not support
+ Unicode on the wire.
+ nomapchars Do not translate any of these seven characters (default).
+ nocase Request case insensitive path name matching (case
+ sensitive is the default if the server supports it).
+ (mount option "ignorecase" is identical to "nocase")
+ posixpaths If CIFS Unix extensions are supported, attempt to
+ negotiate posix path name support which allows certain
+ characters forbidden in typical CIFS filenames, without
+ requiring remapping. (default)
+ noposixpaths If CIFS Unix extensions are supported, do not request
+ posix path name support (this may cause servers to
+ reject creatingfile with certain reserved characters).
+ nounix Disable the CIFS Unix Extensions for this mount (tree
+ connection). This is rarely needed, but it may be useful
+ in order to turn off multiple settings all at once (ie
+ posix acls, posix locks, posix paths, symlink support
+ and retrieving uids/gids/mode from the server) or to
+ work around a bug in server which implement the Unix
+ Extensions.
+ nobrl Do not send byte range lock requests to the server.
+ This is necessary for certain applications that break
+ with cifs style mandatory byte range locks (and most
+ cifs servers do not yet support requesting advisory
+ byte range locks).
+ forcemandatorylock Even if the server supports posix (advisory) byte range
+ locking, send only mandatory lock requests. For some
+ (presumably rare) applications, originally coded for
+ DOS/Windows, which require Windows style mandatory byte range
+ locking, they may be able to take advantage of this option,
+ forcing the cifs client to only send mandatory locks
+ even if the cifs server would support posix advisory locks.
+ "forcemand" is accepted as a shorter form of this mount
+ option.
+ nostrictsync If this mount option is set, when an application does an
+ fsync call then the cifs client does not send an SMB Flush
+ to the server (to force the server to write all dirty data
+ for this file immediately to disk), although cifs still sends
+ all dirty (cached) file data to the server and waits for the
+ server to respond to the write. Since SMB Flush can be
+ very slow, and some servers may be reliable enough (to risk
+ delaying slightly flushing the data to disk on the server),
+ turning on this option may be useful to improve performance for
+ applications that fsync too much, at a small risk of server
+ crash. If this mount option is not set, by default cifs will
+ send an SMB flush request (and wait for a response) on every
+ fsync call.
+ nodfs Disable DFS (global name space support) even if the
+ server claims to support it. This can help work around
+ a problem with parsing of DFS paths with Samba server
+ versions 3.0.24 and 3.0.25.
+ remount remount the share (often used to change from ro to rw mounts
+ or vice versa)
+ cifsacl Report mode bits (e.g. on stat) based on the Windows ACL for
+ the file. (EXPERIMENTAL)
+ servern Specify the server 's netbios name (RFC1001 name) to use
+ when attempting to setup a session to the server.
+ This is needed for mounting to some older servers (such
+ as OS/2 or Windows 98 and Windows ME) since they do not
+ support a default server name. A server name can be up
+ to 15 characters long and is usually uppercased.
+ sfu When the CIFS Unix Extensions are not negotiated, attempt to
+ create device files and fifos in a format compatible with
+ Services for Unix (SFU). In addition retrieve bits 10-12
+ of the mode via the SETFILEBITS extended attribute (as
+ SFU does). In the future the bottom 9 bits of the
+ mode also will be emulated using queries of the security
+ descriptor (ACL).
+ mfsymlinks Enable support for Minshall+French symlinks
+ (see http://wiki.samba.org/index.php/UNIX_Extensions#Minshall.2BFrench_symlinks)
+ This option is ignored when specified together with the
+ 'sfu' option. Minshall+French symlinks are used even if
+ the server supports the CIFS Unix Extensions.
+ sign Must use packet signing (helps avoid unwanted data modification
+ by intermediate systems in the route). Note that signing
+ does not work with lanman or plaintext authentication.
+ seal Must seal (encrypt) all data on this mounted share before
+ sending on the network. Requires support for Unix Extensions.
+ Note that this differs from the sign mount option in that it
+ causes encryption of data sent over this mounted share but other
+ shares mounted to the same server are unaffected.
+ locallease This option is rarely needed. Fcntl F_SETLEASE is
+ used by some applications such as Samba and NFSv4 server to
+ check to see whether a file is cacheable. CIFS has no way
+ to explicitly request a lease, but can check whether a file
+ is cacheable (oplocked). Unfortunately, even if a file
+ is not oplocked, it could still be cacheable (ie cifs client
+ could grant fcntl leases if no other local processes are using
+ the file) for cases for example such as when the server does not
+ support oplocks and the user is sure that the only updates to
+ the file will be from this client. Specifying this mount option
+ will allow the cifs client to check for leases (only) locally
+ for files which are not oplocked instead of denying leases
+ in that case. (EXPERIMENTAL)
+ sec Security mode. Allowed values are:
+ none attempt to connection as a null user (no name)
+ krb5 Use Kerberos version 5 authentication
+ krb5i Use Kerberos authentication and packet signing
+ ntlm Use NTLM password hashing (default)
+ ntlmi Use NTLM password hashing with signing (if
+ /proc/fs/cifs/PacketSigningEnabled on or if
+ server requires signing also can be the default)
+ ntlmv2 Use NTLMv2 password hashing
+ ntlmv2i Use NTLMv2 password hashing with packet signing
+ lanman (if configured in kernel config) use older
+ lanman hash
+hard Retry file operations if server is not responding
+soft Limit retries to unresponsive servers (usually only
+ one retry) before returning an error. (default)
+
+The mount.cifs mount helper also accepts a few mount options before -o
+including:
+
+ -S take password from stdin (equivalent to setting the environment
+ variable "PASSWD_FD=0"
+ -V print mount.cifs version
+ -? display simple usage information
+
+With most 2.6 kernel versions of modutils, the version of the cifs kernel
+module can be displayed via modinfo.
+
+Misc /proc/fs/cifs Flags and Debug Info
+=======================================
+Informational pseudo-files:
+DebugData Displays information about active CIFS sessions and
+ shares, features enabled as well as the cifs.ko
+ version.
+Stats Lists summary resource usage information as well as per
+ share statistics, if CONFIG_CIFS_STATS in enabled
+ in the kernel configuration.
+
+Configuration pseudo-files:
+PacketSigningEnabled If set to one, cifs packet signing is enabled
+ and will be used if the server requires
+ it. If set to two, cifs packet signing is
+ required even if the server considers packet
+ signing optional. (default 1)
+SecurityFlags Flags which control security negotiation and
+ also packet signing. Authentication (may/must)
+ flags (e.g. for NTLM and/or NTLMv2) may be combined with
+ the signing flags. Specifying two different password
+ hashing mechanisms (as "must use") on the other hand
+ does not make much sense. Default flags are
+ 0x07007
+ (NTLM, NTLMv2 and packet signing allowed). The maximum
+ allowable flags if you want to allow mounts to servers
+ using weaker password hashes is 0x37037 (lanman,
+ plaintext, ntlm, ntlmv2, signing allowed). Some
+ SecurityFlags require the corresponding menuconfig
+ options to be enabled (lanman and plaintext require
+ CONFIG_CIFS_WEAK_PW_HASH for example). Enabling
+ plaintext authentication currently requires also
+ enabling lanman authentication in the security flags
+ because the cifs module only supports sending
+ laintext passwords using the older lanman dialect
+ form of the session setup SMB. (e.g. for authentication
+ using plain text passwords, set the SecurityFlags
+ to 0x30030):
+
+ may use packet signing 0x00001
+ must use packet signing 0x01001
+ may use NTLM (most common password hash) 0x00002
+ must use NTLM 0x02002
+ may use NTLMv2 0x00004
+ must use NTLMv2 0x04004
+ may use Kerberos security 0x00008
+ must use Kerberos 0x08008
+ may use lanman (weak) password hash 0x00010
+ must use lanman password hash 0x10010
+ may use plaintext passwords 0x00020
+ must use plaintext passwords 0x20020
+ (reserved for future packet encryption) 0x00040
+
+cifsFYI If set to non-zero value, additional debug information
+ will be logged to the system error log. This field
+ contains three flags controlling different classes of
+ debugging entries. The maximum value it can be set
+ to is 7 which enables all debugging points (default 0).
+ Some debugging statements are not compiled into the
+ cifs kernel unless CONFIG_CIFS_DEBUG2 is enabled in the
+ kernel configuration. cifsFYI may be set to one or
+ nore of the following flags (7 sets them all):
+
+ log cifs informational messages 0x01
+ log return codes from cifs entry points 0x02
+ log slow responses (ie which take longer than 1 second)
+ CONFIG_CIFS_STATS2 must be enabled in .config 0x04
+
+
+traceSMB If set to one, debug information is logged to the
+ system error log with the start of smb requests
+ and responses (default 0)
+LookupCacheEnable If set to one, inode information is kept cached
+ for one second improving performance of lookups
+ (default 1)
+OplockEnabled If set to one, safe distributed caching enabled.
+ (default 1)
+LinuxExtensionsEnabled If set to one then the client will attempt to
+ use the CIFS "UNIX" extensions which are optional
+ protocol enhancements that allow CIFS servers
+ to return accurate UID/GID information as well
+ as support symbolic links. If you use servers
+ such as Samba that support the CIFS Unix
+ extensions but do not want to use symbolic link
+ support and want to map the uid and gid fields
+ to values supplied at mount (rather than the
+ actual values, then set this to zero. (default 1)
+
+These experimental features and tracing can be enabled by changing flags in
+/proc/fs/cifs (after the cifs module has been installed or built into the
+kernel, e.g. insmod cifs). To enable a feature set it to 1 e.g. to enable
+tracing to the kernel message log type:
+
+ echo 7 > /proc/fs/cifs/cifsFYI
+
+cifsFYI functions as a bit mask. Setting it to 1 enables additional kernel
+logging of various informational messages. 2 enables logging of non-zero
+SMB return codes while 4 enables logging of requests that take longer
+than one second to complete (except for byte range lock requests).
+Setting it to 4 requires defining CONFIG_CIFS_STATS2 manually in the
+source code (typically by setting it in the beginning of cifsglob.h),
+and setting it to seven enables all three. Finally, tracing
+the start of smb requests and responses can be enabled via:
+
+ echo 1 > /proc/fs/cifs/traceSMB
+
+Per share (per client mount) statistics are available in /proc/fs/cifs/Stats
+if the kernel was configured with cifs statistics enabled. The statistics
+represent the number of successful (ie non-zero return code from the server)
+SMB responses to some of the more common commands (open, delete, mkdir etc.).
+Also recorded is the total bytes read and bytes written to the server for
+that share. Note that due to client caching effects this can be less than the
+number of bytes read and written by the application running on the client.
+The statistics for the number of total SMBs and oplock breaks are different in
+that they represent all for that share, not just those for which the server
+returned success.
+
+Also note that "cat /proc/fs/cifs/DebugData" will display information about
+the active sessions and the shares that are mounted.
+
+Enabling Kerberos (extended security) works but requires version 1.2 or later
+of the helper program cifs.upcall to be present and to be configured in the
+/etc/request-key.conf file. The cifs.upcall helper program is from the Samba
+project(http://www.samba.org). NTLM and NTLMv2 and LANMAN support do not
+require this helper. Note that NTLMv2 security (which does not require the
+cifs.upcall helper program), instead of using Kerberos, is sufficient for
+some use cases.
+
+DFS support allows transparent redirection to shares in an MS-DFS name space.
+In addition, DFS support for target shares which are specified as UNC
+names which begin with host names (rather than IP addresses) requires
+a user space helper (such as cifs.upcall) to be present in order to
+translate host names to ip address, and the user space helper must also
+be configured in the file /etc/request-key.conf. Samba, Windows servers and
+many NAS appliances support DFS as a way of constructing a global name
+space to ease network configuration and improve reliability.
+
+To use cifs Kerberos and DFS support, the Linux keyutils package should be
+installed and something like the following lines should be added to the
+/etc/request-key.conf file:
+
+create cifs.spnego * * /usr/local/sbin/cifs.upcall %k
+create dns_resolver * * /usr/local/sbin/cifs.upcall %k
+
+CIFS kernel module parameters
+=============================
+These module parameters can be specified or modified either during the time of
+module loading or during the runtime by using the interface
+ /proc/module/cifs/parameters/<param>
+
+i.e. echo "value" > /sys/module/cifs/parameters/<param>
+
+1. enable_oplocks - Enable or disable oplocks. Oplocks are enabled by default.
+ [Y/y/1]. To disable use any of [N/n/0].
+
diff --git a/Documentation/filesystems/cifs/TODO b/Documentation/filesystems/cifs/TODO
new file mode 100644
index 0000000..355abcdc
--- /dev/null
+++ b/Documentation/filesystems/cifs/TODO
@@ -0,0 +1,129 @@
+Version 1.53 May 20, 2008
+
+A Partial List of Missing Features
+==================================
+
+Contributions are welcome. There are plenty of opportunities
+for visible, important contributions to this module. Here
+is a partial list of the known problems and missing features:
+
+a) Support for SecurityDescriptors(Windows/CIFS ACLs) for chmod/chgrp/chown
+so that these operations can be supported to Windows servers
+
+b) Mapping POSIX ACLs (and eventually NFSv4 ACLs) to CIFS
+SecurityDescriptors
+
+c) Better pam/winbind integration (e.g. to handle uid mapping
+better)
+
+d) Cleanup now unneeded SessSetup code in
+fs/cifs/connect.c and add back in NTLMSSP code if any servers
+need it
+
+e) fix NTLMv2 signing when two mounts with different users to same
+server.
+
+f) Directory entry caching relies on a 1 second timer, rather than
+using FindNotify or equivalent. - (started)
+
+g) quota support (needs minor kernel change since quota calls
+to make it to network filesystems or deviceless filesystems)
+
+h) investigate sync behavior (including syncpage) and check
+for proper behavior of intr/nointr
+
+i) improve support for very old servers (OS/2 and Win9x for example)
+Including support for changing the time remotely (utimes command).
+
+j) hook lower into the sockets api (as NFS/SunRPC does) to avoid the
+extra copy in/out of the socket buffers in some cases.
+
+k) Better optimize open (and pathbased setfilesize) to reduce the
+oplock breaks coming from windows srv. Piggyback identical file
+opens on top of each other by incrementing reference count rather
+than resending (helps reduce server resource utilization and avoid
+spurious oplock breaks).
+
+l) Improve performance of readpages by sending more than one read
+at a time when 8 pages or more are requested. In conjuntion
+add support for async_cifs_readpages.
+
+m) Add support for storing symlink info to Windows servers
+in the Extended Attribute format their SFU clients would recognize.
+
+n) Finish fcntl D_NOTIFY support so kde and gnome file list windows
+will autorefresh (partially complete by Asser). Needs minor kernel
+vfs change to support removing D_NOTIFY on a file.
+
+o) Add GUI tool to configure /proc/fs/cifs settings and for display of
+the CIFS statistics (started)
+
+p) implement support for security and trusted categories of xattrs
+(requires minor protocol extension) to enable better support for SELINUX
+
+q) Implement O_DIRECT flag on open (already supported on mount)
+
+r) Create UID mapping facility so server UIDs can be mapped on a per
+mount or a per server basis to client UIDs or nobody if no mapping
+exists. This is helpful when Unix extensions are negotiated to
+allow better permission checking when UIDs differ on the server
+and client. Add new protocol request to the CIFS protocol
+standard for asking the server for the corresponding name of a
+particular uid.
+
+s) Add support for CIFS Unix and also the newer POSIX extensions to the
+server side for Samba 4.
+
+t) In support for OS/2 (LANMAN 1.2 and LANMAN2.1 based SMB servers)
+need to add ability to set time to server (utimes command)
+
+u) DOS attrs - returned as pseudo-xattr in Samba format (check VFAT and NTFS for this too)
+
+v) mount check for unmatched uids
+
+w) Add support for new vfs entry point for fallocate
+
+x) Fix Samba 3 server to handle Linux kernel aio so dbench with lots of
+processes can proceed better in parallel (on the server)
+
+y) Fix Samba 3 to handle reads/writes over 127K (and remove the cifs mount
+restriction of wsize max being 127K)
+
+KNOWN BUGS (updated April 24, 2007)
+====================================
+See http://bugzilla.samba.org - search on product "CifsVFS" for
+current bug list.
+
+1) existing symbolic links (Windows reparse points) are recognized but
+can not be created remotely. They are implemented for Samba and those that
+support the CIFS Unix extensions, although earlier versions of Samba
+overly restrict the pathnames.
+2) follow_link and readdir code does not follow dfs junctions
+but recognizes them
+3) create of new files to FAT partitions on Windows servers can
+succeed but still return access denied (appears to be Windows
+server not cifs client problem) and has not been reproduced recently.
+NTFS partitions do not have this problem.
+4) Unix/POSIX capabilities are reset after reconnection, and affect
+a few fields in the tree connection but we do do not know which
+superblocks to apply these changes to. We should probably walk
+the list of superblocks to set these. Also need to check the
+flags on the second mount to the same share, and see if we
+can do the same trick that NFS does to remount duplicate shares.
+
+Misc testing to do
+==================
+1) check out max path names and max path name components against various server
+types. Try nested symlinks (8 deep). Return max path name in stat -f information
+
+2) Modify file portion of ltp so it can run against a mounted network
+share and run it against cifs vfs in automated fashion.
+
+3) Additional performance testing and optimization using iozone and similar -
+there are some easy changes that can be done to parallelize sequential writes,
+and when signing is disabled to request larger read sizes (larger than
+negotiated size) and send larger write sizes to modern servers.
+
+4) More exhaustively test against less common servers. More testing
+against Windows 9x, Windows ME servers.
+
diff --git a/Documentation/filesystems/cifs.txt b/Documentation/filesystems/cifs/cifs.txt
index 49cc923..49cc923 100644
--- a/Documentation/filesystems/cifs.txt
+++ b/Documentation/filesystems/cifs/cifs.txt
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