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Based on kernel version 4.0. Page generated on 2015-04-14 21:24 EST.

1	Version 2.03 August 1, 2014
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) SMB3 (and SMB3.02) missing optional features:
11	   - RDMA
12	   - multichannel (started)
13	   - directory leases (improved metadata caching)
14	   - T10 copy offload (copy chunk is only mechanism supported)
15	   - encrypted shares
16	
17	b) improved sparse file support
18	
19	c) Directory entry caching relies on a 1 second timer, rather than
20	using FindNotify or equivalent.  - (started)
21	
22	d) quota support (needs minor kernel change since quota calls
23	to make it to network filesystems or deviceless filesystems)
24	
25	e) improve support for very old servers (OS/2 and Win9x for example)
26	Including support for changing the time remotely (utimes command).
27	
28	f) hook lower into the sockets api (as NFS/SunRPC does) to avoid the
29	extra copy in/out of the socket buffers in some cases.
30	
31	g) Better optimize open (and pathbased setfilesize) to reduce the
32	oplock breaks coming from windows srv.  Piggyback identical file
33	opens on top of each other by incrementing reference count rather
34	than resending (helps reduce server resource utilization and avoid
35	spurious oplock breaks).
36	
37	h) Add support for storing symlink info to Windows servers
38	in the Extended Attribute format their SFU clients would recognize.
39	
40	i) Finish inotify support so kde and gnome file list windows
41	will autorefresh (partially complete by Asser). Needs minor kernel
42	vfs change to support removing D_NOTIFY on a file.   
43	
44	j) Add GUI tool to configure /proc/fs/cifs settings and for display of
45	the CIFS statistics (started)
46	
47	k) implement support for security and trusted categories of xattrs
48	(requires minor protocol extension) to enable better support for SELINUX
49	
50	l) Implement O_DIRECT flag on open (already supported on mount)
51	
52	m) Create UID mapping facility so server UIDs can be mapped on a per
53	mount or a per server basis to client UIDs or nobody if no mapping
54	exists.  This is helpful when Unix extensions are negotiated to
55	allow better permission checking when UIDs differ on the server
56	and client.  Add new protocol request to the CIFS protocol 
57	standard for asking the server for the corresponding name of a
58	particular uid.
59	
60	n) DOS attrs - returned as pseudo-xattr in Samba format (check VFAT and NTFS for this too)
61	
62	o) mount check for unmatched uids
63	
64	p) Add support for new vfs entry point for fallocate
65	
66	q) Add tools to take advantage of cifs/smb3 specific ioctls and features
67	such as "CopyChunk" (fast server side file copy)
68	
69	r) encrypted file support
70	
71	s) improved stats gathering, tools (perhaps integration with nfsometer?)
72	
73	t) allow setting more NTFS/SMB3 file attributes remotely (currently limited to compressed
74	file attribute via chflags)
75	
76	u) mount helper GUI (to simplify the various configuration options on mount)
77	
78	
79	KNOWN BUGS
80	====================================
81	See http://bugzilla.samba.org - search on product "CifsVFS" for
82	current bug list.  Also check http://bugzilla.kernel.org (Product = File System, Component = CIFS)
83	
84	1) existing symbolic links (Windows reparse points) are recognized but
85	can not be created remotely. They are implemented for Samba and those that
86	support the CIFS Unix extensions, although earlier versions of Samba
87	overly restrict the pathnames.
88	2) follow_link and readdir code does not follow dfs junctions
89	but recognizes them
90	
91	Misc testing to do
92	==================
93	1) check out max path names and max path name components against various server
94	types. Try nested symlinks (8 deep). Return max path name in stat -f information
95	
96	2) Improve xfstest's cifs enablement and adapt xfstests where needed to test
97	cifs better
98	
99	3) Additional performance testing and optimization using iozone and similar - 
100	there are some easy changes that can be done to parallelize sequential writes,
101	and when signing is disabled to request larger read sizes (larger than 
102	negotiated size) and send larger write sizes to modern servers.
103	
104	4) More exhaustively test against less common servers
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