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Based on kernel version 3.15.4. Page generated on 2014-07-07 09:02 EST.

1	Version 1.53 May 20, 2008
2	
3	A Partial List of Missing Features
4	==================================
5	
6	Contributions are welcome.  There are plenty of opportunities
7	for visible, important contributions to this module.  Here
8	is a partial list of the known problems and missing features:
9	
10	a) Support for SecurityDescriptors(Windows/CIFS ACLs) for chmod/chgrp/chown
11	so that these operations can be supported to Windows servers
12	
13	b) Mapping POSIX ACLs (and eventually NFSv4 ACLs) to CIFS
14	SecurityDescriptors
15	
16	c) Better pam/winbind integration (e.g. to handle uid mapping
17	better)
18	
19	d) Cleanup now unneeded SessSetup code in
20	fs/cifs/connect.c and add back in NTLMSSP code if any servers
21	need it
22	
23	e) fix NTLMv2 signing when two mounts with different users to same
24	server.
25	
26	f) Directory entry caching relies on a 1 second timer, rather than 
27	using FindNotify or equivalent.  - (started)
28	
29	g) quota support (needs minor kernel change since quota calls
30	to make it to network filesystems or deviceless filesystems)
31	
32	h) investigate sync behavior (including syncpage) and check  
33	for proper behavior of intr/nointr
34	
35	i) improve support for very old servers (OS/2 and Win9x for example)
36	Including support for changing the time remotely (utimes command).
37	
38	j) hook lower into the sockets api (as NFS/SunRPC does) to avoid the
39	extra copy in/out of the socket buffers in some cases.
40	
41	k) Better optimize open (and pathbased setfilesize) to reduce the
42	oplock breaks coming from windows srv.  Piggyback identical file
43	opens on top of each other by incrementing reference count rather
44	than resending (helps reduce server resource utilization and avoid
45	spurious oplock breaks).
46	
47	l) Improve performance of readpages by sending more than one read
48	at a time when 8 pages or more are requested. In conjuntion
49	add support for async_cifs_readpages.
50	
51	m) Add support for storing symlink info to Windows servers 
52	in the Extended Attribute format their SFU clients would recognize.
53	
54	n) Finish fcntl D_NOTIFY support so kde and gnome file list windows
55	will autorefresh (partially complete by Asser). Needs minor kernel
56	vfs change to support removing D_NOTIFY on a file.   
57	
58	o) Add GUI tool to configure /proc/fs/cifs settings and for display of
59	the CIFS statistics (started)
60	
61	p) implement support for security and trusted categories of xattrs
62	(requires minor protocol extension) to enable better support for SELINUX
63	
64	q) Implement O_DIRECT flag on open (already supported on mount)
65	
66	r) Create UID mapping facility so server UIDs can be mapped on a per
67	mount or a per server basis to client UIDs or nobody if no mapping
68	exists.  This is helpful when Unix extensions are negotiated to
69	allow better permission checking when UIDs differ on the server
70	and client.  Add new protocol request to the CIFS protocol 
71	standard for asking the server for the corresponding name of a
72	particular uid.
73	
74	s) Add support for CIFS Unix and also the newer POSIX extensions to the
75	server side for Samba 4.
76	
77	t) In support for OS/2 (LANMAN 1.2 and LANMAN2.1 based SMB servers) 
78	need to add ability to set time to server (utimes command)
79	
80	u) DOS attrs - returned as pseudo-xattr in Samba format (check VFAT and NTFS for this too)
81	
82	v) mount check for unmatched uids
83	
84	w) Add support for new vfs entry point for fallocate
85	
86	x) Fix Samba 3 server to handle Linux kernel aio so dbench with lots of 
87	processes can proceed better in parallel (on the server)
88	
89	y) Fix Samba 3 to handle reads/writes over 127K (and remove the cifs mount
90	restriction of wsize max being 127K) 
91	
92	KNOWN BUGS (updated April 24, 2007)
93	====================================
94	See http://bugzilla.samba.org - search on product "CifsVFS" for
95	current bug list.
96	
97	1) existing symbolic links (Windows reparse points) are recognized but
98	can not be created remotely. They are implemented for Samba and those that
99	support the CIFS Unix extensions, although earlier versions of Samba
100	overly restrict the pathnames.
101	2) follow_link and readdir code does not follow dfs junctions
102	but recognizes them
103	3) create of new files to FAT partitions on Windows servers can
104	succeed but still return access denied (appears to be Windows 
105	server not cifs client problem) and has not been reproduced recently.
106	NTFS partitions do not have this problem.
107	4) Unix/POSIX capabilities are reset after reconnection, and affect
108	a few fields in the tree connection but we do do not know which
109	superblocks to apply these changes to.  We should probably walk
110	the list of superblocks to set these.  Also need to check the
111	flags on the second mount to the same share, and see if we
112	can do the same trick that NFS does to remount duplicate shares.
113	
114	Misc testing to do
115	==================
116	1) check out max path names and max path name components against various server
117	types. Try nested symlinks (8 deep). Return max path name in stat -f information
118	
119	2) Modify file portion of ltp so it can run against a mounted network
120	share and run it against cifs vfs in automated fashion.
121	
122	3) Additional performance testing and optimization using iozone and similar - 
123	there are some easy changes that can be done to parallelize sequential writes,
124	and when signing is disabled to request larger read sizes (larger than 
125	negotiated size) and send larger write sizes to modern servers.
126	
127	4) More exhaustively test against less common servers.  More testing
128	against Windows 9x, Windows ME servers.
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