Documentation/filesystems/9p.txt

   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@sandia.gov>
  10 and Maya Gokhale.  Additional development by Greg Watson
  11 <gwatson@lanl.gov> and most recently Eric Van Hensbergen
  12 <ericvh@gmail.com>, Latchesar Ionkov <lucho@ionkov.net> and Russ Cox
  13 <rsc@swtch.com>.
  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://www.xcpu.org/xcpu-talk.pdf
  22         * KVMFS: control file system for KVM
  23                 http://www.xcpu.org/kvmfs.pdf
  24         * CellFS: A New ProgrammingModel for the Cell BE
  25                 http://www.xcpu.org/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
  52   uname=name    user name to attempt mount as on the remote server.  The
  53                 server may override or ignore this value.  Certain user
  54                 names may require authentication.
  55
  56   aname=name    aname specifies the file tree to access when the server is
  57                 offering several exported file systems.
  58
  59   cache=mode    specifies a caching policy.  By default, no caches are used.
  60                         loose = no attempts are made at consistency,
  61                                 intended for exclusive, read-only mounts
  62
  63   debug=n       specifies debug level.  The debug level is a bitmask.
  64                         0x01 = display verbose error messages
  65                         0x02 = developer debug (DEBUG_CURRENT)
  66                         0x04 = display 9p trace
  67                         0x08 = display VFS trace
  68                         0x10 = display Marshalling debug
  69                         0x20 = display RPC debug
  70                         0x40 = display transport debug
  71                         0x80 = display allocation debug
  72
  73   rfdno=n       the file descriptor for reading with trans=fd
  74
  75   wfdno=n       the file descriptor for writing with trans=fd
  76
  77   maxdata=n     the number of bytes to use for 9p packet payload (msize)
  78
  79   port=n        port to connect to on the remote server
  80
  81   noextend      force legacy mode (no 9p2000.u semantics)
  82
  83   dfltuid       attempt to mount as a particular uid
  84
  85   dfltgid       attempt to mount with a particular gid
  86
  87   afid          security channel - used by Plan 9 authentication protocols
  88
  89   nodevmap      do not map special files - represent them as normal files.
  90                 This can be used to share devices/named pipes/sockets between
  91                 hosts.  This functionality will be expanded in later versions.
  92
  93   access        there are three access modes.
  94                         user  = if a user tries to access a file on v9fs
  95                                 filesystem for the first time, v9fs sends an
  96                                 attach command (Tattach) for that user.
  97                                 This is the default mode.
  98                         <uid> = allows only user with uid=<uid> to access
  99                                 the files on the mounted filesystem
 100                         any   = v9fs does single attach and performs all
 101                                 operations as one user
 102
 103 RESOURCES
 104 =========
 105
 106 Our current recommendation is to use Inferno (http://www.vitanuova.com/inferno)
 107 as the 9p server.  You can start a 9p server under Inferno by issuing the
 108 following command:
 109    ; styxlisten -A tcp!*!564 export '#U*'
 110
 111 The -A specifies an unauthenticated export.  The 564 is the port # (you may
 112 have to choose a higher port number if running as a normal user).  The '#U*'
 113 specifies exporting the root of the Linux name space.  You may specify a
 114 subset of the namespace by extending the path: '#U*'/tmp would just export
 115 /tmp.  For more information, see the Inferno manual pages covering styxlisten
 116 and export.
 117
 118 A Linux version of the 9p server is now maintained under the npfs project
 119 on sourceforge (http://sourceforge.net/projects/npfs).  The currently
 120 maintained version is the single-threaded version of the server (named spfs)
 121 available from the same CVS repository.
 122
 123 There are user and developer mailing lists available through the v9fs project
 124 on sourceforge (http://sourceforge.net/projects/v9fs).
 125
 126 News and other information is maintained on SWiK (http://swik.net/v9fs).
 127
 128 Bug reports may be issued through the kernel.org bugzilla
 129 (http://bugzilla.kernel.org)
 130
 131 For more information on the Plan 9 Operating System check out
 132 http://plan9.bell-labs.com/plan9
 133
 134 For information on Plan 9 from User Space (Plan 9 applications and libraries
 135 ported to Linux/BSD/OSX/etc) check out http://swtch.com/plan9
 136
 137
 138 STATUS
 139 ======
 140
 141 The 2.6 kernel support is working on PPC and x86.
 142
 143 PLEASE USE THE KERNEL BUGZILLA TO REPORT PROBLEMS. (http://bugzilla.kernel.org)
 144