xref: /openbmc/linux/include/net/9p/9p.h (revision 8fa5723aa7e053d498336b48448b292fc2e0458b)
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  *
42  * These flags are passed at mount time to turn on various levels of
43  * verbosity and tracing which will be output to the system logs.
44  */
45 
46 enum p9_debug_flags {
47 	P9_DEBUG_ERROR = 	(1<<0),
48 	P9_DEBUG_9P = 		(1<<2),
49 	P9_DEBUG_VFS =		(1<<3),
50 	P9_DEBUG_CONV =		(1<<4),
51 	P9_DEBUG_MUX =		(1<<5),
52 	P9_DEBUG_TRANS =	(1<<6),
53 	P9_DEBUG_SLABS =      	(1<<7),
54 	P9_DEBUG_FCALL =	(1<<8),
55 	P9_DEBUG_FID =		(1<<9),
56 	P9_DEBUG_PKT =		(1<<10),
57 };
58 
59 #ifdef CONFIG_NET_9P_DEBUG
60 extern unsigned int p9_debug_level;
61 
62 #define P9_DPRINTK(level, format, arg...) \
63 do {  \
64 	if ((p9_debug_level & level) == level) {\
65 		if (level == P9_DEBUG_9P) \
66 			printk(KERN_NOTICE "(%8.8d) " \
67 			format , task_pid_nr(current) , ## arg); \
68 		else \
69 			printk(KERN_NOTICE "-- %s (%d): " \
70 			format , __func__, task_pid_nr(current) , ## arg); \
71 	} \
72 } while (0)
73 
74 #else
75 #define P9_DPRINTK(level, format, arg...)  do { } while (0)
76 #endif
77 
78 #define P9_EPRINTK(level, format, arg...) \
79 do { \
80 	printk(level "9p: %s (%d): " \
81 		format , __func__, task_pid_nr(current), ## arg); \
82 } while (0)
83 
84 /**
85  * enum p9_msg_t - 9P message types
86  * @P9_TVERSION: version handshake request
87  * @P9_RVERSION: version handshake response
88  * @P9_TAUTH: request to establish authentication channel
89  * @P9_RAUTH: response with authentication information
90  * @P9_TATTACH: establish user access to file service
91  * @P9_RATTACH: response with top level handle to file hierarchy
92  * @P9_TERROR: not used
93  * @P9_RERROR: response for any failed request
94  * @P9_TFLUSH: request to abort a previous request
95  * @P9_RFLUSH: response when previous request has been cancelled
96  * @P9_TWALK: descend a directory hierarchy
97  * @P9_RWALK: response with new handle for position within hierarchy
98  * @P9_TOPEN: prepare a handle for I/O on an existing file
99  * @P9_ROPEN: response with file access information
100  * @P9_TCREATE: prepare a handle for I/O on a new file
101  * @P9_RCREATE: response with file access information
102  * @P9_TREAD: request to transfer data from a file or directory
103  * @P9_RREAD: response with data requested
104  * @P9_TWRITE: reuqest to transfer data to a file
105  * @P9_RWRITE: response with out much data was transfered to file
106  * @P9_TCLUNK: forget about a handle to an entity within the file system
107  * @P9_RCLUNK: response when server has forgotten about the handle
108  * @P9_TREMOVE: request to remove an entity from the hierarchy
109  * @P9_RREMOVE: response when server has removed the entity
110  * @P9_TSTAT: request file entity attributes
111  * @P9_RSTAT: response with file entity attributes
112  * @P9_TWSTAT: request to update file entity attributes
113  * @P9_RWSTAT: response when file entity attributes are updated
114  *
115  * There are 14 basic operations in 9P2000, paired as
116  * requests and responses.  The one special case is ERROR
117  * as there is no @P9_TERROR request for clients to transmit to
118  * the server, but the server may respond to any other request
119  * with an @P9_RERROR.
120  *
121  * See Also: http://plan9.bell-labs.com/sys/man/5/INDEX.html
122  */
123 
124 enum p9_msg_t {
125 	P9_TVERSION = 100,
126 	P9_RVERSION,
127 	P9_TAUTH = 102,
128 	P9_RAUTH,
129 	P9_TATTACH = 104,
130 	P9_RATTACH,
131 	P9_TERROR = 106,
132 	P9_RERROR,
133 	P9_TFLUSH = 108,
134 	P9_RFLUSH,
135 	P9_TWALK = 110,
136 	P9_RWALK,
137 	P9_TOPEN = 112,
138 	P9_ROPEN,
139 	P9_TCREATE = 114,
140 	P9_RCREATE,
141 	P9_TREAD = 116,
142 	P9_RREAD,
143 	P9_TWRITE = 118,
144 	P9_RWRITE,
145 	P9_TCLUNK = 120,
146 	P9_RCLUNK,
147 	P9_TREMOVE = 122,
148 	P9_RREMOVE,
149 	P9_TSTAT = 124,
150 	P9_RSTAT,
151 	P9_TWSTAT = 126,
152 	P9_RWSTAT,
153 };
154 
155 /**
156  * enum p9_open_mode_t - 9P open modes
157  * @P9_OREAD: open file for reading only
158  * @P9_OWRITE: open file for writing only
159  * @P9_ORDWR: open file for reading or writing
160  * @P9_OEXEC: open file for execution
161  * @P9_OTRUNC: truncate file to zero-length before opening it
162  * @P9_OREXEC: close the file when an exec(2) system call is made
163  * @P9_ORCLOSE: remove the file when the file is closed
164  * @P9_OAPPEND: open the file and seek to the end
165  * @P9_OEXCL: only create a file, do not open it
166  *
167  * 9P open modes differ slightly from Posix standard modes.
168  * In particular, there are extra modes which specify different
169  * semantic behaviors than may be available on standard Posix
170  * systems.  For example, @P9_OREXEC and @P9_ORCLOSE are modes that
171  * most likely will not be issued from the Linux VFS client, but may
172  * be supported by servers.
173  *
174  * See Also: http://plan9.bell-labs.com/magic/man2html/2/open
175  */
176 
177 enum p9_open_mode_t {
178 	P9_OREAD = 0x00,
179 	P9_OWRITE = 0x01,
180 	P9_ORDWR = 0x02,
181 	P9_OEXEC = 0x03,
182 	P9_OTRUNC = 0x10,
183 	P9_OREXEC = 0x20,
184 	P9_ORCLOSE = 0x40,
185 	P9_OAPPEND = 0x80,
186 	P9_OEXCL = 0x1000,
187 };
188 
189 /**
190  * enum p9_perm_t - 9P permissions
191  * @P9_DMDIR: mode bite for directories
192  * @P9_DMAPPEND: mode bit for is append-only
193  * @P9_DMEXCL: mode bit for excluse use (only one open handle allowed)
194  * @P9_DMMOUNT: mode bite for mount points
195  * @P9_DMAUTH: mode bit for authentication file
196  * @P9_DMTMP: mode bit for non-backed-up files
197  * @P9_DMSYMLINK: mode bit for symbolic links (9P2000.u)
198  * @P9_DMLINK: mode bit for hard-link (9P2000.u)
199  * @P9_DMDEVICE: mode bit for device files (9P2000.u)
200  * @P9_DMNAMEDPIPE: mode bit for named pipe (9P2000.u)
201  * @P9_DMSOCKET: mode bit for socket (9P2000.u)
202  * @P9_DMSETUID: mode bit for setuid (9P2000.u)
203  * @P9_DMSETGID: mode bit for setgid (9P2000.u)
204  * @P9_DMSETVTX: mode bit for sticky bit (9P2000.u)
205  *
206  * 9P permissions differ slightly from Posix standard modes.
207  *
208  * See Also: http://plan9.bell-labs.com/magic/man2html/2/stat
209  */
210 enum p9_perm_t {
211 	P9_DMDIR = 0x80000000,
212 	P9_DMAPPEND = 0x40000000,
213 	P9_DMEXCL = 0x20000000,
214 	P9_DMMOUNT = 0x10000000,
215 	P9_DMAUTH = 0x08000000,
216 	P9_DMTMP = 0x04000000,
217 /* 9P2000.u extensions */
218 	P9_DMSYMLINK = 0x02000000,
219 	P9_DMLINK = 0x01000000,
220 	P9_DMDEVICE = 0x00800000,
221 	P9_DMNAMEDPIPE = 0x00200000,
222 	P9_DMSOCKET = 0x00100000,
223 	P9_DMSETUID = 0x00080000,
224 	P9_DMSETGID = 0x00040000,
225 	P9_DMSETVTX = 0x00010000,
226 };
227 
228 /**
229  * enum p9_qid_t - QID types
230  * @P9_QTDIR: directory
231  * @P9_QTAPPEND: append-only
232  * @P9_QTEXCL: excluse use (only one open handle allowed)
233  * @P9_QTMOUNT: mount points
234  * @P9_QTAUTH: authentication file
235  * @P9_QTTMP: non-backed-up files
236  * @P9_QTSYMLINK: symbolic links (9P2000.u)
237  * @P9_QTLINK: hard-link (9P2000.u)
238  * @P9_QTFILE: normal files
239  *
240  * QID types are a subset of permissions - they are primarily
241  * used to differentiate semantics for a file system entity via
242  * a jump-table.  Their value is also the most signifigant 16 bits
243  * of the permission_t
244  *
245  * See Also: http://plan9.bell-labs.com/magic/man2html/2/stat
246  */
247 enum p9_qid_t {
248 	P9_QTDIR = 0x80,
249 	P9_QTAPPEND = 0x40,
250 	P9_QTEXCL = 0x20,
251 	P9_QTMOUNT = 0x10,
252 	P9_QTAUTH = 0x08,
253 	P9_QTTMP = 0x04,
254 	P9_QTSYMLINK = 0x02,
255 	P9_QTLINK = 0x01,
256 	P9_QTFILE = 0x00,
257 };
258 
259 /* 9P Magic Numbers */
260 #define P9_NOTAG	(u16)(~0)
261 #define P9_NOFID	(u32)(~0)
262 #define P9_MAXWELEM	16
263 
264 /* ample room for Twrite/Rread header */
265 #define P9_IOHDRSZ	24
266 
267 /**
268  * struct p9_str - length prefixed string type
269  * @len: length of the string
270  * @str: the string
271  *
272  * The protocol uses length prefixed strings for all
273  * string data, so we replicate that for our internal
274  * string members.
275  */
276 
277 struct p9_str {
278 	u16 len;
279 	char *str;
280 };
281 
282 /**
283  * struct p9_qid - file system entity information
284  * @type: 8-bit type &p9_qid_t
285  * @version: 16-bit monotonically incrementing version number
286  * @path: 64-bit per-server-unique ID for a file system element
287  *
288  * qids are identifiers used by 9P servers to track file system
289  * entities.  The type is used to differentiate semantics for operations
290  * on the entity (ie. read means something different on a directory than
291  * on a file).  The path provides a server unique index for an entity
292  * (roughly analogous to an inode number), while the version is updated
293  * every time a file is modified and can be used to maintain cache
294  * coherency between clients and serves.
295  * Servers will often differentiate purely synthetic entities by setting
296  * their version to 0, signaling that they should never be cached and
297  * should be accessed synchronously.
298  *
299  * See Also://plan9.bell-labs.com/magic/man2html/2/stat
300  */
301 
302 struct p9_qid {
303 	u8 type;
304 	u32 version;
305 	u64 path;
306 };
307 
308 /**
309  * struct p9_stat - file system metadata information
310  * @size: length prefix for this stat structure instance
311  * @type: the type of the server (equivilent to a major number)
312  * @dev: the sub-type of the server (equivilent to a minor number)
313  * @qid: unique id from the server of type &p9_qid
314  * @mode: Plan 9 format permissions of type &p9_perm_t
315  * @atime: Last access/read time
316  * @mtime: Last modify/write time
317  * @length: file length
318  * @name: last element of path (aka filename) in type &p9_str
319  * @uid: owner name in type &p9_str
320  * @gid: group owner in type &p9_str
321  * @muid: last modifier in type &p9_str
322  * @extension: area used to encode extended UNIX support in type &p9_str
323  * @n_uid: numeric user id of owner (part of 9p2000.u extension)
324  * @n_gid: numeric group id (part of 9p2000.u extension)
325  * @n_muid: numeric user id of laster modifier (part of 9p2000.u extension)
326  *
327  * See Also: http://plan9.bell-labs.com/magic/man2html/2/stat
328  */
329 
330 struct p9_wstat {
331 	u16 size;
332 	u16 type;
333 	u32 dev;
334 	struct p9_qid qid;
335 	u32 mode;
336 	u32 atime;
337 	u32 mtime;
338 	u64 length;
339 	char *name;
340 	char *uid;
341 	char *gid;
342 	char *muid;
343 	char *extension;	/* 9p2000.u extensions */
344 	u32 n_uid;		/* 9p2000.u extensions */
345 	u32 n_gid;		/* 9p2000.u extensions */
346 	u32 n_muid;		/* 9p2000.u extensions */
347 };
348 
349 /* Structures for Protocol Operations */
350 struct p9_tversion {
351 	u32 msize;
352 	struct p9_str version;
353 };
354 
355 struct p9_rversion {
356 	u32 msize;
357 	struct p9_str version;
358 };
359 
360 struct p9_tauth {
361 	u32 afid;
362 	struct p9_str uname;
363 	struct p9_str aname;
364 	u32 n_uname;		/* 9P2000.u extensions */
365 };
366 
367 struct p9_rauth {
368 	struct p9_qid qid;
369 };
370 
371 struct p9_rerror {
372 	struct p9_str error;
373 	u32 errno;		/* 9p2000.u extension */
374 };
375 
376 struct p9_tflush {
377 	u16 oldtag;
378 };
379 
380 struct p9_rflush {
381 };
382 
383 struct p9_tattach {
384 	u32 fid;
385 	u32 afid;
386 	struct p9_str uname;
387 	struct p9_str aname;
388 	u32 n_uname;		/* 9P2000.u extensions */
389 };
390 
391 struct p9_rattach {
392 	struct p9_qid qid;
393 };
394 
395 struct p9_twalk {
396 	u32 fid;
397 	u32 newfid;
398 	u16 nwname;
399 	struct p9_str wnames[16];
400 };
401 
402 struct p9_rwalk {
403 	u16 nwqid;
404 	struct p9_qid wqids[16];
405 };
406 
407 struct p9_topen {
408 	u32 fid;
409 	u8 mode;
410 };
411 
412 struct p9_ropen {
413 	struct p9_qid qid;
414 	u32 iounit;
415 };
416 
417 struct p9_tcreate {
418 	u32 fid;
419 	struct p9_str name;
420 	u32 perm;
421 	u8 mode;
422 	struct p9_str extension;
423 };
424 
425 struct p9_rcreate {
426 	struct p9_qid qid;
427 	u32 iounit;
428 };
429 
430 struct p9_tread {
431 	u32 fid;
432 	u64 offset;
433 	u32 count;
434 };
435 
436 struct p9_rread {
437 	u32 count;
438 	u8 *data;
439 };
440 
441 struct p9_twrite {
442 	u32 fid;
443 	u64 offset;
444 	u32 count;
445 	u8 *data;
446 };
447 
448 struct p9_rwrite {
449 	u32 count;
450 };
451 
452 struct p9_tclunk {
453 	u32 fid;
454 };
455 
456 struct p9_rclunk {
457 };
458 
459 struct p9_tremove {
460 	u32 fid;
461 };
462 
463 struct p9_rremove {
464 };
465 
466 struct p9_tstat {
467 	u32 fid;
468 };
469 
470 struct p9_rstat {
471 	struct p9_wstat stat;
472 };
473 
474 struct p9_twstat {
475 	u32 fid;
476 	struct p9_wstat stat;
477 };
478 
479 struct p9_rwstat {
480 };
481 
482 /**
483  * struct p9_fcall - primary packet structure
484  * @size: prefixed length of the structure
485  * @id: protocol operating identifier of type &p9_msg_t
486  * @tag: transaction id of the request
487  * @offset: used by marshalling routines to track currentposition in buffer
488  * @capacity: used by marshalling routines to track total capacity
489  * @sdata: payload
490  *
491  * &p9_fcall represents the structure for all 9P RPC
492  * transactions.  Requests are packaged into fcalls, and reponses
493  * must be extracted from them.
494  *
495  * See Also: http://plan9.bell-labs.com/magic/man2html/2/fcall
496  */
497 
498 struct p9_fcall {
499 	u32 size;
500 	u8 id;
501 	u16 tag;
502 
503 	size_t offset;
504 	size_t capacity;
505 
506 	uint8_t *sdata;
507 };
508 
509 struct p9_idpool;
510 
511 int p9_errstr2errno(char *errstr, int len);
512 
513 struct p9_idpool *p9_idpool_create(void);
514 void p9_idpool_destroy(struct p9_idpool *);
515 int p9_idpool_get(struct p9_idpool *p);
516 void p9_idpool_put(int id, struct p9_idpool *p);
517 int p9_idpool_check(int id, struct p9_idpool *p);
518 
519 int p9_error_init(void);
520 int p9_errstr2errno(char *, int);
521 int p9_trans_fd_init(void);
522 void p9_trans_fd_exit(void);
523 #endif /* NET_9P_H */
524