xref: /openbmc/linux/include/net/9p/9p.h (revision e8e0929d)
1 /*
2  * include/net/9p/9p.h
3  *
4  * 9P protocol definitions.
5  *
6  *  Copyright (C) 2005 by Latchesar Ionkov <lucho@ionkov.net>
7  *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
8  *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
9  *
10  *  This program is free software; you can redistribute it and/or modify
11  *  it under the terms of the GNU General Public License version 2
12  *  as published by the Free Software Foundation.
13  *
14  *  This program is distributed in the hope that it will be useful,
15  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
16  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  *  GNU General Public License for more details.
18  *
19  *  You should have received a copy of the GNU General Public License
20  *  along with this program; if not, write to:
21  *  Free Software Foundation
22  *  51 Franklin Street, Fifth Floor
23  *  Boston, MA  02111-1301  USA
24  *
25  */
26 
27 #ifndef NET_9P_H
28 #define NET_9P_H
29 
30 /**
31  * enum p9_debug_flags - bits for mount time debug parameter
32  * @P9_DEBUG_ERROR: more verbose error messages including original error string
33  * @P9_DEBUG_9P: 9P protocol tracing
34  * @P9_DEBUG_VFS: VFS API tracing
35  * @P9_DEBUG_CONV: protocol conversion tracing
36  * @P9_DEBUG_MUX: trace management of concurrent transactions
37  * @P9_DEBUG_TRANS: transport tracing
38  * @P9_DEBUG_SLABS: memory management tracing
39  * @P9_DEBUG_FCALL: verbose dump of protocol messages
40  * @P9_DEBUG_FID: fid allocation/deallocation tracking
41  * @P9_DEBUG_PKT: packet marshalling/unmarshalling
42  * @P9_DEBUG_FSC: FS-cache tracing
43  *
44  * These flags are passed at mount time to turn on various levels of
45  * verbosity and tracing which will be output to the system logs.
46  */
47 
48 enum p9_debug_flags {
49 	P9_DEBUG_ERROR = 	(1<<0),
50 	P9_DEBUG_9P = 		(1<<2),
51 	P9_DEBUG_VFS =		(1<<3),
52 	P9_DEBUG_CONV =		(1<<4),
53 	P9_DEBUG_MUX =		(1<<5),
54 	P9_DEBUG_TRANS =	(1<<6),
55 	P9_DEBUG_SLABS =      	(1<<7),
56 	P9_DEBUG_FCALL =	(1<<8),
57 	P9_DEBUG_FID =		(1<<9),
58 	P9_DEBUG_PKT =		(1<<10),
59 	P9_DEBUG_FSC =		(1<<11),
60 };
61 
62 #ifdef CONFIG_NET_9P_DEBUG
63 extern unsigned int p9_debug_level;
64 
65 #define P9_DPRINTK(level, format, arg...) \
66 do {  \
67 	if ((p9_debug_level & level) == level) {\
68 		if (level == P9_DEBUG_9P) \
69 			printk(KERN_NOTICE "(%8.8d) " \
70 			format , task_pid_nr(current) , ## arg); \
71 		else \
72 			printk(KERN_NOTICE "-- %s (%d): " \
73 			format , __func__, task_pid_nr(current) , ## arg); \
74 	} \
75 } while (0)
76 
77 #else
78 #define P9_DPRINTK(level, format, arg...)  do { } while (0)
79 #endif
80 
81 #define P9_EPRINTK(level, format, arg...) \
82 do { \
83 	printk(level "9p: %s (%d): " \
84 		format , __func__, task_pid_nr(current), ## arg); \
85 } while (0)
86 
87 /**
88  * enum p9_msg_t - 9P message types
89  * @P9_TVERSION: version handshake request
90  * @P9_RVERSION: version handshake response
91  * @P9_TAUTH: request to establish authentication channel
92  * @P9_RAUTH: response with authentication information
93  * @P9_TATTACH: establish user access to file service
94  * @P9_RATTACH: response with top level handle to file hierarchy
95  * @P9_TERROR: not used
96  * @P9_RERROR: response for any failed request
97  * @P9_TFLUSH: request to abort a previous request
98  * @P9_RFLUSH: response when previous request has been cancelled
99  * @P9_TWALK: descend a directory hierarchy
100  * @P9_RWALK: response with new handle for position within hierarchy
101  * @P9_TOPEN: prepare a handle for I/O on an existing file
102  * @P9_ROPEN: response with file access information
103  * @P9_TCREATE: prepare a handle for I/O on a new file
104  * @P9_RCREATE: response with file access information
105  * @P9_TREAD: request to transfer data from a file or directory
106  * @P9_RREAD: response with data requested
107  * @P9_TWRITE: reuqest to transfer data to a file
108  * @P9_RWRITE: response with out much data was transfered to file
109  * @P9_TCLUNK: forget about a handle to an entity within the file system
110  * @P9_RCLUNK: response when server has forgotten about the handle
111  * @P9_TREMOVE: request to remove an entity from the hierarchy
112  * @P9_RREMOVE: response when server has removed the entity
113  * @P9_TSTAT: request file entity attributes
114  * @P9_RSTAT: response with file entity attributes
115  * @P9_TWSTAT: request to update file entity attributes
116  * @P9_RWSTAT: response when file entity attributes are updated
117  *
118  * There are 14 basic operations in 9P2000, paired as
119  * requests and responses.  The one special case is ERROR
120  * as there is no @P9_TERROR request for clients to transmit to
121  * the server, but the server may respond to any other request
122  * with an @P9_RERROR.
123  *
124  * See Also: http://plan9.bell-labs.com/sys/man/5/INDEX.html
125  */
126 
127 enum p9_msg_t {
128 	P9_TVERSION = 100,
129 	P9_RVERSION,
130 	P9_TAUTH = 102,
131 	P9_RAUTH,
132 	P9_TATTACH = 104,
133 	P9_RATTACH,
134 	P9_TERROR = 106,
135 	P9_RERROR,
136 	P9_TFLUSH = 108,
137 	P9_RFLUSH,
138 	P9_TWALK = 110,
139 	P9_RWALK,
140 	P9_TOPEN = 112,
141 	P9_ROPEN,
142 	P9_TCREATE = 114,
143 	P9_RCREATE,
144 	P9_TREAD = 116,
145 	P9_RREAD,
146 	P9_TWRITE = 118,
147 	P9_RWRITE,
148 	P9_TCLUNK = 120,
149 	P9_RCLUNK,
150 	P9_TREMOVE = 122,
151 	P9_RREMOVE,
152 	P9_TSTAT = 124,
153 	P9_RSTAT,
154 	P9_TWSTAT = 126,
155 	P9_RWSTAT,
156 };
157 
158 /**
159  * enum p9_open_mode_t - 9P open modes
160  * @P9_OREAD: open file for reading only
161  * @P9_OWRITE: open file for writing only
162  * @P9_ORDWR: open file for reading or writing
163  * @P9_OEXEC: open file for execution
164  * @P9_OTRUNC: truncate file to zero-length before opening it
165  * @P9_OREXEC: close the file when an exec(2) system call is made
166  * @P9_ORCLOSE: remove the file when the file is closed
167  * @P9_OAPPEND: open the file and seek to the end
168  * @P9_OEXCL: only create a file, do not open it
169  *
170  * 9P open modes differ slightly from Posix standard modes.
171  * In particular, there are extra modes which specify different
172  * semantic behaviors than may be available on standard Posix
173  * systems.  For example, @P9_OREXEC and @P9_ORCLOSE are modes that
174  * most likely will not be issued from the Linux VFS client, but may
175  * be supported by servers.
176  *
177  * See Also: http://plan9.bell-labs.com/magic/man2html/2/open
178  */
179 
180 enum p9_open_mode_t {
181 	P9_OREAD = 0x00,
182 	P9_OWRITE = 0x01,
183 	P9_ORDWR = 0x02,
184 	P9_OEXEC = 0x03,
185 	P9_OTRUNC = 0x10,
186 	P9_OREXEC = 0x20,
187 	P9_ORCLOSE = 0x40,
188 	P9_OAPPEND = 0x80,
189 	P9_OEXCL = 0x1000,
190 };
191 
192 /**
193  * enum p9_perm_t - 9P permissions
194  * @P9_DMDIR: mode bite for directories
195  * @P9_DMAPPEND: mode bit for is append-only
196  * @P9_DMEXCL: mode bit for excluse use (only one open handle allowed)
197  * @P9_DMMOUNT: mode bite for mount points
198  * @P9_DMAUTH: mode bit for authentication file
199  * @P9_DMTMP: mode bit for non-backed-up files
200  * @P9_DMSYMLINK: mode bit for symbolic links (9P2000.u)
201  * @P9_DMLINK: mode bit for hard-link (9P2000.u)
202  * @P9_DMDEVICE: mode bit for device files (9P2000.u)
203  * @P9_DMNAMEDPIPE: mode bit for named pipe (9P2000.u)
204  * @P9_DMSOCKET: mode bit for socket (9P2000.u)
205  * @P9_DMSETUID: mode bit for setuid (9P2000.u)
206  * @P9_DMSETGID: mode bit for setgid (9P2000.u)
207  * @P9_DMSETVTX: mode bit for sticky bit (9P2000.u)
208  *
209  * 9P permissions differ slightly from Posix standard modes.
210  *
211  * See Also: http://plan9.bell-labs.com/magic/man2html/2/stat
212  */
213 enum p9_perm_t {
214 	P9_DMDIR = 0x80000000,
215 	P9_DMAPPEND = 0x40000000,
216 	P9_DMEXCL = 0x20000000,
217 	P9_DMMOUNT = 0x10000000,
218 	P9_DMAUTH = 0x08000000,
219 	P9_DMTMP = 0x04000000,
220 /* 9P2000.u extensions */
221 	P9_DMSYMLINK = 0x02000000,
222 	P9_DMLINK = 0x01000000,
223 	P9_DMDEVICE = 0x00800000,
224 	P9_DMNAMEDPIPE = 0x00200000,
225 	P9_DMSOCKET = 0x00100000,
226 	P9_DMSETUID = 0x00080000,
227 	P9_DMSETGID = 0x00040000,
228 	P9_DMSETVTX = 0x00010000,
229 };
230 
231 /**
232  * enum p9_qid_t - QID types
233  * @P9_QTDIR: directory
234  * @P9_QTAPPEND: append-only
235  * @P9_QTEXCL: excluse use (only one open handle allowed)
236  * @P9_QTMOUNT: mount points
237  * @P9_QTAUTH: authentication file
238  * @P9_QTTMP: non-backed-up files
239  * @P9_QTSYMLINK: symbolic links (9P2000.u)
240  * @P9_QTLINK: hard-link (9P2000.u)
241  * @P9_QTFILE: normal files
242  *
243  * QID types are a subset of permissions - they are primarily
244  * used to differentiate semantics for a file system entity via
245  * a jump-table.  Their value is also the most signifigant 16 bits
246  * of the permission_t
247  *
248  * See Also: http://plan9.bell-labs.com/magic/man2html/2/stat
249  */
250 enum p9_qid_t {
251 	P9_QTDIR = 0x80,
252 	P9_QTAPPEND = 0x40,
253 	P9_QTEXCL = 0x20,
254 	P9_QTMOUNT = 0x10,
255 	P9_QTAUTH = 0x08,
256 	P9_QTTMP = 0x04,
257 	P9_QTSYMLINK = 0x02,
258 	P9_QTLINK = 0x01,
259 	P9_QTFILE = 0x00,
260 };
261 
262 /* 9P Magic Numbers */
263 #define P9_NOTAG	(u16)(~0)
264 #define P9_NOFID	(u32)(~0)
265 #define P9_MAXWELEM	16
266 
267 /* ample room for Twrite/Rread header */
268 #define P9_IOHDRSZ	24
269 
270 /**
271  * struct p9_str - length prefixed string type
272  * @len: length of the string
273  * @str: the string
274  *
275  * The protocol uses length prefixed strings for all
276  * string data, so we replicate that for our internal
277  * string members.
278  */
279 
280 struct p9_str {
281 	u16 len;
282 	char *str;
283 };
284 
285 /**
286  * struct p9_qid - file system entity information
287  * @type: 8-bit type &p9_qid_t
288  * @version: 16-bit monotonically incrementing version number
289  * @path: 64-bit per-server-unique ID for a file system element
290  *
291  * qids are identifiers used by 9P servers to track file system
292  * entities.  The type is used to differentiate semantics for operations
293  * on the entity (ie. read means something different on a directory than
294  * on a file).  The path provides a server unique index for an entity
295  * (roughly analogous to an inode number), while the version is updated
296  * every time a file is modified and can be used to maintain cache
297  * coherency between clients and serves.
298  * Servers will often differentiate purely synthetic entities by setting
299  * their version to 0, signaling that they should never be cached and
300  * should be accessed synchronously.
301  *
302  * See Also://plan9.bell-labs.com/magic/man2html/2/stat
303  */
304 
305 struct p9_qid {
306 	u8 type;
307 	u32 version;
308 	u64 path;
309 };
310 
311 /**
312  * struct p9_stat - file system metadata information
313  * @size: length prefix for this stat structure instance
314  * @type: the type of the server (equivilent to a major number)
315  * @dev: the sub-type of the server (equivilent to a minor number)
316  * @qid: unique id from the server of type &p9_qid
317  * @mode: Plan 9 format permissions of type &p9_perm_t
318  * @atime: Last access/read time
319  * @mtime: Last modify/write time
320  * @length: file length
321  * @name: last element of path (aka filename) in type &p9_str
322  * @uid: owner name in type &p9_str
323  * @gid: group owner in type &p9_str
324  * @muid: last modifier in type &p9_str
325  * @extension: area used to encode extended UNIX support in type &p9_str
326  * @n_uid: numeric user id of owner (part of 9p2000.u extension)
327  * @n_gid: numeric group id (part of 9p2000.u extension)
328  * @n_muid: numeric user id of laster modifier (part of 9p2000.u extension)
329  *
330  * See Also: http://plan9.bell-labs.com/magic/man2html/2/stat
331  */
332 
333 struct p9_wstat {
334 	u16 size;
335 	u16 type;
336 	u32 dev;
337 	struct p9_qid qid;
338 	u32 mode;
339 	u32 atime;
340 	u32 mtime;
341 	u64 length;
342 	char *name;
343 	char *uid;
344 	char *gid;
345 	char *muid;
346 	char *extension;	/* 9p2000.u extensions */
347 	u32 n_uid;		/* 9p2000.u extensions */
348 	u32 n_gid;		/* 9p2000.u extensions */
349 	u32 n_muid;		/* 9p2000.u extensions */
350 };
351 
352 /* Structures for Protocol Operations */
353 struct p9_tversion {
354 	u32 msize;
355 	struct p9_str version;
356 };
357 
358 struct p9_rversion {
359 	u32 msize;
360 	struct p9_str version;
361 };
362 
363 struct p9_tauth {
364 	u32 afid;
365 	struct p9_str uname;
366 	struct p9_str aname;
367 	u32 n_uname;		/* 9P2000.u extensions */
368 };
369 
370 struct p9_rauth {
371 	struct p9_qid qid;
372 };
373 
374 struct p9_rerror {
375 	struct p9_str error;
376 	u32 errno;		/* 9p2000.u extension */
377 };
378 
379 struct p9_tflush {
380 	u16 oldtag;
381 };
382 
383 struct p9_rflush {
384 };
385 
386 struct p9_tattach {
387 	u32 fid;
388 	u32 afid;
389 	struct p9_str uname;
390 	struct p9_str aname;
391 	u32 n_uname;		/* 9P2000.u extensions */
392 };
393 
394 struct p9_rattach {
395 	struct p9_qid qid;
396 };
397 
398 struct p9_twalk {
399 	u32 fid;
400 	u32 newfid;
401 	u16 nwname;
402 	struct p9_str wnames[16];
403 };
404 
405 struct p9_rwalk {
406 	u16 nwqid;
407 	struct p9_qid wqids[16];
408 };
409 
410 struct p9_topen {
411 	u32 fid;
412 	u8 mode;
413 };
414 
415 struct p9_ropen {
416 	struct p9_qid qid;
417 	u32 iounit;
418 };
419 
420 struct p9_tcreate {
421 	u32 fid;
422 	struct p9_str name;
423 	u32 perm;
424 	u8 mode;
425 	struct p9_str extension;
426 };
427 
428 struct p9_rcreate {
429 	struct p9_qid qid;
430 	u32 iounit;
431 };
432 
433 struct p9_tread {
434 	u32 fid;
435 	u64 offset;
436 	u32 count;
437 };
438 
439 struct p9_rread {
440 	u32 count;
441 	u8 *data;
442 };
443 
444 struct p9_twrite {
445 	u32 fid;
446 	u64 offset;
447 	u32 count;
448 	u8 *data;
449 };
450 
451 struct p9_rwrite {
452 	u32 count;
453 };
454 
455 struct p9_tclunk {
456 	u32 fid;
457 };
458 
459 struct p9_rclunk {
460 };
461 
462 struct p9_tremove {
463 	u32 fid;
464 };
465 
466 struct p9_rremove {
467 };
468 
469 struct p9_tstat {
470 	u32 fid;
471 };
472 
473 struct p9_rstat {
474 	struct p9_wstat stat;
475 };
476 
477 struct p9_twstat {
478 	u32 fid;
479 	struct p9_wstat stat;
480 };
481 
482 struct p9_rwstat {
483 };
484 
485 /**
486  * struct p9_fcall - primary packet structure
487  * @size: prefixed length of the structure
488  * @id: protocol operating identifier of type &p9_msg_t
489  * @tag: transaction id of the request
490  * @offset: used by marshalling routines to track currentposition in buffer
491  * @capacity: used by marshalling routines to track total capacity
492  * @sdata: payload
493  *
494  * &p9_fcall represents the structure for all 9P RPC
495  * transactions.  Requests are packaged into fcalls, and reponses
496  * must be extracted from them.
497  *
498  * See Also: http://plan9.bell-labs.com/magic/man2html/2/fcall
499  */
500 
501 struct p9_fcall {
502 	u32 size;
503 	u8 id;
504 	u16 tag;
505 
506 	size_t offset;
507 	size_t capacity;
508 
509 	uint8_t *sdata;
510 };
511 
512 struct p9_idpool;
513 
514 int p9_errstr2errno(char *errstr, int len);
515 
516 struct p9_idpool *p9_idpool_create(void);
517 void p9_idpool_destroy(struct p9_idpool *);
518 int p9_idpool_get(struct p9_idpool *p);
519 void p9_idpool_put(int id, struct p9_idpool *p);
520 int p9_idpool_check(int id, struct p9_idpool *p);
521 
522 int p9_error_init(void);
523 int p9_errstr2errno(char *, int);
524 int p9_trans_fd_init(void);
525 void p9_trans_fd_exit(void);
526 #endif /* NET_9P_H */
527