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Based on kernel version 2.6.33. Page generated on 2010-02-24 15:36 EST.

1		  	    v9fs: Plan 9 Resource Sharing for Linux
2			    =======================================
3	
4	ABOUT
5	=====
6	
7	v9fs is a Unix implementation of the Plan 9 9p remote filesystem protocol.
8	
9	This software was originally developed by Ron Minnich <rminnich[AT]sandia[DOT]gov>
10	and Maya Gokhale.  Additional development by Greg Watson
11	<gwatson[AT]lanl[DOT]gov> and most recently Eric Van Hensbergen
12	<ericvh[AT]gmail.com>, Latchesar Ionkov <lucho@ionkov[DOT]net> and Russ Cox
13	<rsc[AT]swtch.com>[DOT]
14	
15	The best detailed explanation of the Linux implementation and applications of
16	the 9p client is available in the form of a USENIX paper:
17	   http://www.usenix.org/events/usenix05/tech/freenix/hensbergen.html
18	
19	Other applications are described in the following papers:
20		* XCPU & Clustering
21			http://xcpu.org/papers/xcpu-talk.pdf
22		* KVMFS: control file system for KVM
23			http://xcpu.org/papers/kvmfs.pdf
24		* CellFS: A New Programming Model for the Cell BE
25			http://xcpu.org/papers/cellfs-talk.pdf
26		* PROSE I/O: Using 9p to enable Application Partitions
27			http://plan9.escet.urjc.es/iwp9/cready/PROSE_iwp9_2006.pdf
28	
29	USAGE
30	=====
31	
32	For remote file server:
33	
34		mount -t 9p 10.10.1.2 /mnt/9
35	
36	For Plan 9 From User Space applications (http://swtch.com/plan9)
37	
38		mount -t 9p `namespace`/acme /mnt/9 -o trans=unix,uname=$USER
39	
40	OPTIONS
41	=======
42	
43	  trans=name	select an alternative transport.  Valid options are
44	  		currently:
45				unix 	- specifying a named pipe mount point
46				tcp	- specifying a normal TCP/IP connection
47				fd   	- used passed file descriptors for connection
48	                                (see rfdno and wfdno)
49				virtio	- connect to the next virtio channel available
50					(from lguest or KVM with trans_virtio module)
51				rdma	- connect to a specified RDMA channel
52	
53	  uname=name	user name to attempt mount as on the remote server.  The
54	  		server may override or ignore this value.  Certain user
55			names may require authentication.
56	
57	  aname=name	aname specifies the file tree to access when the server is
58	  		offering several exported file systems.
59	
60	  cache=mode	specifies a caching policy.  By default, no caches are used.
61				loose = no attempts are made at consistency,
62	                                intended for exclusive, read-only mounts
63				fscache = use FS-Cache for a persistent, read-only
64					cache backend.
65	
66	  debug=n	specifies debug level.  The debug level is a bitmask.
67				0x01  = display verbose error messages
68				0x02  = developer debug (DEBUG_CURRENT)
69				0x04  = display 9p trace
70				0x08  = display VFS trace
71				0x10  = display Marshalling debug
72				0x20  = display RPC debug
73				0x40  = display transport debug
74				0x80  = display allocation debug
75				0x100 = display protocol message debug
76				0x200 = display Fid debug
77				0x400 = display packet debug
78				0x800 = display fscache tracing debug
79	
80	  rfdno=n	the file descriptor for reading with trans=fd
81	
82	  wfdno=n	the file descriptor for writing with trans=fd
83	
84	  maxdata=n	the number of bytes to use for 9p packet payload (msize)
85	
86	  port=n	port to connect to on the remote server
87	
88	  noextend	force legacy mode (no 9p2000.u semantics)
89	
90	  dfltuid	attempt to mount as a particular uid
91	
92	  dfltgid	attempt to mount with a particular gid
93	
94	  afid		security channel - used by Plan 9 authentication protocols
95	
96	  nodevmap	do not map special files - represent them as normal files.
97	  		This can be used to share devices/named pipes/sockets between
98			hosts.  This functionality will be expanded in later versions.
99	
100	  access	there are three access modes.
101				user  = if a user tries to access a file on v9fs
102				        filesystem for the first time, v9fs sends an
103				        attach command (Tattach) for that user.
104					This is the default mode.
105				<uid> = allows only user with uid=<uid> to access
106					the files on the mounted filesystem
107				any   = v9fs does single attach and performs all
108					operations as one user
109	
110	  cachetag	cache tag to use the specified persistent cache.
111			cache tags for existing cache sessions can be listed at
112			/sys/fs/9p/caches. (applies only to cache=fscache)
113	
114	RESOURCES
115	=========
116	
117	Our current recommendation is to use Inferno (http://www.vitanuova.com/inferno)
118	as the 9p server.  You can start a 9p server under Inferno by issuing the
119	following command:
120	   ; styxlisten -A tcp!*!564 export '#U*'
121	
122	The -A specifies an unauthenticated export.  The 564 is the port # (you may
123	have to choose a higher port number if running as a normal user).  The '#U*'
124	specifies exporting the root of the Linux name space.  You may specify a
125	subset of the namespace by extending the path: '#U*'/tmp would just export
126	/tmp.  For more information, see the Inferno manual pages covering styxlisten
127	and export.
128	
129	A Linux version of the 9p server is now maintained under the npfs project
130	on sourceforge (http://sourceforge.net/projects/npfs).  The currently
131	maintained version is the single-threaded version of the server (named spfs)
132	available from the same SVN repository.
133	
134	There are user and developer mailing lists available through the v9fs project
135	on sourceforge (http://sourceforge.net/projects/v9fs).
136	
137	A stand-alone version of the module (which should build for any 2.6 kernel)
138	is available via (http://github.com/ericvh/9p-sac/tree/master)
139	
140	News and other information is maintained on SWiK (http://swik.net/v9fs)
141	and the Wiki (http://sf.net/apps/mediawiki/v9fs/index.php).
142	
143	Bug reports may be issued through the kernel.org bugzilla 
144	(http://bugzilla.kernel.org)
145	
146	For more information on the Plan 9 Operating System check out
147	http://plan9.bell-labs.com/plan9
148	
149	For information on Plan 9 from User Space (Plan 9 applications and libraries
150	ported to Linux/BSD/OSX/etc) check out http://swtch.com/plan9
151	
152	
153	STATUS
154	======
155	
156	The 2.6 kernel support is working on PPC and x86.
157	
158	PLEASE USE THE KERNEL BUGZILLA TO REPORT PROBLEMS. (http://bugzilla.kernel.org)
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