xref: /openbmc/linux/include/net/9p/9p.h (revision f15cbe6f1a4b4d9df59142fc8e4abb973302cf44)
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 #ifdef CONFIG_NET_9P_DEBUG
31 
32 /**
33  * enum p9_debug_flags - bits for mount time debug parameter
34  * @P9_DEBUG_ERROR: more verbose error messages including original error string
35  * @P9_DEBUG_9P: 9P protocol tracing
36  * @P9_DEBUG_VFS: VFS API tracing
37  * @P9_DEBUG_CONV: protocol conversion tracing
38  * @P9_DEBUG_MUX: trace management of concurrent transactions
39  * @P9_DEBUG_TRANS: transport tracing
40  * @P9_DEBUG_SLABS: memory management tracing
41  * @P9_DEBUG_FCALL: verbose dump of protocol messages
42  *
43  * These flags are passed at mount time to turn on various levels of
44  * verbosity and tracing which will be output to the system logs.
45  */
46 
47 enum p9_debug_flags {
48 	P9_DEBUG_ERROR = 	(1<<0),
49 	P9_DEBUG_9P = 		(1<<2),
50 	P9_DEBUG_VFS =		(1<<3),
51 	P9_DEBUG_CONV =		(1<<4),
52 	P9_DEBUG_MUX =		(1<<5),
53 	P9_DEBUG_TRANS =	(1<<6),
54 	P9_DEBUG_SLABS =      	(1<<7),
55 	P9_DEBUG_FCALL =	(1<<8),
56 };
57 
58 extern unsigned int p9_debug_level;
59 
60 #define P9_DPRINTK(level, format, arg...) \
61 do {  \
62 	if ((p9_debug_level & level) == level) \
63 		printk(KERN_NOTICE "-- %s (%d): " \
64 		format , __FUNCTION__, task_pid_nr(current) , ## arg); \
65 } while (0)
66 
67 #define PRINT_FCALL_ERROR(s, fcall) P9_DPRINTK(P9_DEBUG_ERROR,   \
68 	"%s: %.*s\n", s, fcall?fcall->params.rerror.error.len:0, \
69 	fcall?fcall->params.rerror.error.str:"");
70 
71 #else
72 #define P9_DPRINTK(level, format, arg...)  do { } while (0)
73 #define PRINT_FCALL_ERROR(s, fcall) do { } while (0)
74 #endif
75 
76 #define P9_EPRINTK(level, format, arg...) \
77 do { \
78 	printk(level "9p: %s (%d): " \
79 		format , __FUNCTION__, task_pid_nr(current), ## arg); \
80 } while (0)
81 
82 /**
83  * enum p9_msg_t - 9P message types
84  * @P9_TVERSION: version handshake request
85  * @P9_RVERSION: version handshake response
86  * @P9_TAUTH: request to establish authentication channel
87  * @P9_RAUTH: response with authentication information
88  * @P9_TATTACH: establish user access to file service
89  * @P9_RATTACH: response with top level handle to file hierarchy
90  * @P9_TERROR: not used
91  * @P9_RERROR: response for any failed request
92  * @P9_TFLUSH: request to abort a previous request
93  * @P9_RFLUSH: response when previous request has been cancelled
94  * @P9_TWALK: descend a directory hierarchy
95  * @P9_RWALK: response with new handle for position within hierarchy
96  * @P9_TOPEN: prepare a handle for I/O on an existing file
97  * @P9_ROPEN: response with file access information
98  * @P9_TCREATE: prepare a handle for I/O on a new file
99  * @P9_RCREATE: response with file access information
100  * @P9_TREAD: request to transfer data from a file or directory
101  * @P9_RREAD: response with data requested
102  * @P9_TWRITE: reuqest to transfer data to a file
103  * @P9_RWRITE: response with out much data was transfered to file
104  * @P9_TCLUNK: forget about a handle to an entity within the file system
105  * @P9_RCLUNK: response when server has forgotten about the handle
106  * @P9_TREMOVE: request to remove an entity from the hierarchy
107  * @P9_RREMOVE: response when server has removed the entity
108  * @P9_TSTAT: request file entity attributes
109  * @P9_RSTAT: response with file entity attributes
110  * @P9_TWSTAT: request to update file entity attributes
111  * @P9_RWSTAT: response when file entity attributes are updated
112  *
113  * There are 14 basic operations in 9P2000, paired as
114  * requests and responses.  The one special case is ERROR
115  * as there is no @P9_TERROR request for clients to transmit to
116  * the server, but the server may respond to any other request
117  * with an @P9_RERROR.
118  *
119  * See Also: http://plan9.bell-labs.com/sys/man/5/INDEX.html
120  */
121 
122 enum p9_msg_t {
123 	P9_TVERSION = 100,
124 	P9_RVERSION,
125 	P9_TAUTH = 102,
126 	P9_RAUTH,
127 	P9_TATTACH = 104,
128 	P9_RATTACH,
129 	P9_TERROR = 106,
130 	P9_RERROR,
131 	P9_TFLUSH = 108,
132 	P9_RFLUSH,
133 	P9_TWALK = 110,
134 	P9_RWALK,
135 	P9_TOPEN = 112,
136 	P9_ROPEN,
137 	P9_TCREATE = 114,
138 	P9_RCREATE,
139 	P9_TREAD = 116,
140 	P9_RREAD,
141 	P9_TWRITE = 118,
142 	P9_RWRITE,
143 	P9_TCLUNK = 120,
144 	P9_RCLUNK,
145 	P9_TREMOVE = 122,
146 	P9_RREMOVE,
147 	P9_TSTAT = 124,
148 	P9_RSTAT,
149 	P9_TWSTAT = 126,
150 	P9_RWSTAT,
151 };
152 
153 /**
154  * enum p9_open_mode_t - 9P open modes
155  * @P9_OREAD: open file for reading only
156  * @P9_OWRITE: open file for writing only
157  * @P9_ORDWR: open file for reading or writing
158  * @P9_OEXEC: open file for execution
159  * @P9_OTRUNC: truncate file to zero-length before opening it
160  * @P9_OREXEC: close the file when an exec(2) system call is made
161  * @P9_ORCLOSE: remove the file when the file is closed
162  * @P9_OAPPEND: open the file and seek to the end
163  * @P9_OEXCL: only create a file, do not open it
164  *
165  * 9P open modes differ slightly from Posix standard modes.
166  * In particular, there are extra modes which specify different
167  * semantic behaviors than may be available on standard Posix
168  * systems.  For example, @P9_OREXEC and @P9_ORCLOSE are modes that
169  * most likely will not be issued from the Linux VFS client, but may
170  * be supported by servers.
171  *
172  * See Also: http://plan9.bell-labs.com/magic/man2html/2/open
173  */
174 
175 enum p9_open_mode_t {
176 	P9_OREAD = 0x00,
177 	P9_OWRITE = 0x01,
178 	P9_ORDWR = 0x02,
179 	P9_OEXEC = 0x03,
180 	P9_OTRUNC = 0x10,
181 	P9_OREXEC = 0x20,
182 	P9_ORCLOSE = 0x40,
183 	P9_OAPPEND = 0x80,
184 	P9_OEXCL = 0x1000,
185 };
186 
187 /**
188  * enum p9_perm_t - 9P permissions
189  * @P9_DMDIR: mode bite for directories
190  * @P9_DMAPPEND: mode bit for is append-only
191  * @P9_DMEXCL: mode bit for excluse use (only one open handle allowed)
192  * @P9_DMMOUNT: mode bite for mount points
193  * @P9_DMAUTH: mode bit for authentication file
194  * @P9_DMTMP: mode bit for non-backed-up files
195  * @P9_DMSYMLINK: mode bit for symbolic links (9P2000.u)
196  * @P9_DMLINK: mode bit for hard-link (9P2000.u)
197  * @P9_DMDEVICE: mode bit for device files (9P2000.u)
198  * @P9_DMNAMEDPIPE: mode bit for named pipe (9P2000.u)
199  * @P9_DMSOCKET: mode bit for socket (9P2000.u)
200  * @P9_DMSETUID: mode bit for setuid (9P2000.u)
201  * @P9_DMSETGID: mode bit for setgid (9P2000.u)
202  * @P9_DMSETVTX: mode bit for sticky bit (9P2000.u)
203  *
204  * 9P permissions differ slightly from Posix standard modes.
205  *
206  * See Also: http://plan9.bell-labs.com/magic/man2html/2/stat
207  */
208 enum p9_perm_t {
209 	P9_DMDIR = 0x80000000,
210 	P9_DMAPPEND = 0x40000000,
211 	P9_DMEXCL = 0x20000000,
212 	P9_DMMOUNT = 0x10000000,
213 	P9_DMAUTH = 0x08000000,
214 	P9_DMTMP = 0x04000000,
215 /* 9P2000.u extensions */
216 	P9_DMSYMLINK = 0x02000000,
217 	P9_DMLINK = 0x01000000,
218 	P9_DMDEVICE = 0x00800000,
219 	P9_DMNAMEDPIPE = 0x00200000,
220 	P9_DMSOCKET = 0x00100000,
221 	P9_DMSETUID = 0x00080000,
222 	P9_DMSETGID = 0x00040000,
223 	P9_DMSETVTX = 0x00010000,
224 };
225 
226 /**
227  * enum p9_qid_t - QID types
228  * @P9_QTDIR: directory
229  * @P9_QTAPPEND: append-only
230  * @P9_QTEXCL: excluse use (only one open handle allowed)
231  * @P9_QTMOUNT: mount points
232  * @P9_QTAUTH: authentication file
233  * @P9_QTTMP: non-backed-up files
234  * @P9_QTSYMLINK: symbolic links (9P2000.u)
235  * @P9_QTLINK: hard-link (9P2000.u)
236  * @P9_QTFILE: normal files
237  *
238  * QID types are a subset of permissions - they are primarily
239  * used to differentiate semantics for a file system entity via
240  * a jump-table.  Their value is also the most signifigant 16 bits
241  * of the permission_t
242  *
243  * See Also: http://plan9.bell-labs.com/magic/man2html/2/stat
244  */
245 enum p9_qid_t {
246 	P9_QTDIR = 0x80,
247 	P9_QTAPPEND = 0x40,
248 	P9_QTEXCL = 0x20,
249 	P9_QTMOUNT = 0x10,
250 	P9_QTAUTH = 0x08,
251 	P9_QTTMP = 0x04,
252 	P9_QTSYMLINK = 0x02,
253 	P9_QTLINK = 0x01,
254 	P9_QTFILE = 0x00,
255 };
256 
257 /* 9P Magic Numbers */
258 #define P9_NOTAG	(u16)(~0)
259 #define P9_NOFID	(u32)(~0)
260 #define P9_MAXWELEM	16
261 
262 /* ample room for Twrite/Rread header */
263 #define P9_IOHDRSZ	24
264 
265 /**
266  * struct p9_str - length prefixed string type
267  * @len: length of the string
268  * @str: the string
269  *
270  * The protocol uses length prefixed strings for all
271  * string data, so we replicate that for our internal
272  * string members.
273  */
274 
275 struct p9_str {
276 	u16 len;
277 	char *str;
278 };
279 
280 /**
281  * struct p9_qid - file system entity information
282  * @type: 8-bit type &p9_qid_t
283  * @version: 16-bit monotonically incrementing version number
284  * @path: 64-bit per-server-unique ID for a file system element
285  *
286  * qids are identifiers used by 9P servers to track file system
287  * entities.  The type is used to differentiate semantics for operations
288  * on the entity (ie. read means something different on a directory than
289  * on a file).  The path provides a server unique index for an entity
290  * (roughly analogous to an inode number), while the version is updated
291  * every time a file is modified and can be used to maintain cache
292  * coherency between clients and serves.
293  * Servers will often differentiate purely synthetic entities by setting
294  * their version to 0, signaling that they should never be cached and
295  * should be accessed synchronously.
296  *
297  * See Also://plan9.bell-labs.com/magic/man2html/2/stat
298  */
299 
300 struct p9_qid {
301 	u8 type;
302 	u32 version;
303 	u64 path;
304 };
305 
306 /**
307  * struct p9_stat - file system metadata information
308  * @size: length prefix for this stat structure instance
309  * @type: the type of the server (equivilent to a major number)
310  * @dev: the sub-type of the server (equivilent to a minor number)
311  * @qid: unique id from the server of type &p9_qid
312  * @mode: Plan 9 format permissions of type &p9_perm_t
313  * @atime: Last access/read time
314  * @mtime: Last modify/write time
315  * @length: file length
316  * @name: last element of path (aka filename) in type &p9_str
317  * @uid: owner name in type &p9_str
318  * @gid: group owner in type &p9_str
319  * @muid: last modifier in type &p9_str
320  * @extension: area used to encode extended UNIX support in type &p9_str
321  * @n_uid: numeric user id of owner (part of 9p2000.u extension)
322  * @n_gid: numeric group id (part of 9p2000.u extension)
323  * @n_muid: numeric user id of laster modifier (part of 9p2000.u extension)
324  *
325  * See Also: http://plan9.bell-labs.com/magic/man2html/2/stat
326  */
327 
328 struct p9_stat {
329 	u16 size;
330 	u16 type;
331 	u32 dev;
332 	struct p9_qid qid;
333 	u32 mode;
334 	u32 atime;
335 	u32 mtime;
336 	u64 length;
337 	struct p9_str name;
338 	struct p9_str uid;
339 	struct p9_str gid;
340 	struct p9_str muid;
341 	struct p9_str extension;	/* 9p2000.u extensions */
342 	u32 n_uid;			/* 9p2000.u extensions */
343 	u32 n_gid;			/* 9p2000.u extensions */
344 	u32 n_muid;			/* 9p2000.u extensions */
345 };
346 
347 /*
348  * file metadata (stat) structure used to create Twstat message
349  * The is identical to &p9_stat, but the strings don't point to
350  * the same memory block and should be freed separately
351  *
352  * See Also: http://plan9.bell-labs.com/magic/man2html/2/stat
353  */
354 
355 struct p9_wstat {
356 	u16 size;
357 	u16 type;
358 	u32 dev;
359 	struct p9_qid qid;
360 	u32 mode;
361 	u32 atime;
362 	u32 mtime;
363 	u64 length;
364 	char *name;
365 	char *uid;
366 	char *gid;
367 	char *muid;
368 	char *extension;	/* 9p2000.u extensions */
369 	u32 n_uid;		/* 9p2000.u extensions */
370 	u32 n_gid;		/* 9p2000.u extensions */
371 	u32 n_muid;		/* 9p2000.u extensions */
372 };
373 
374 /* Structures for Protocol Operations */
375 struct p9_tversion {
376 	u32 msize;
377 	struct p9_str version;
378 };
379 
380 struct p9_rversion {
381 	u32 msize;
382 	struct p9_str version;
383 };
384 
385 struct p9_tauth {
386 	u32 afid;
387 	struct p9_str uname;
388 	struct p9_str aname;
389 	u32 n_uname;		/* 9P2000.u extensions */
390 };
391 
392 struct p9_rauth {
393 	struct p9_qid qid;
394 };
395 
396 struct p9_rerror {
397 	struct p9_str error;
398 	u32 errno;		/* 9p2000.u extension */
399 };
400 
401 struct p9_tflush {
402 	u16 oldtag;
403 };
404 
405 struct p9_rflush {
406 };
407 
408 struct p9_tattach {
409 	u32 fid;
410 	u32 afid;
411 	struct p9_str uname;
412 	struct p9_str aname;
413 	u32 n_uname;		/* 9P2000.u extensions */
414 };
415 
416 struct p9_rattach {
417 	struct p9_qid qid;
418 };
419 
420 struct p9_twalk {
421 	u32 fid;
422 	u32 newfid;
423 	u16 nwname;
424 	struct p9_str wnames[16];
425 };
426 
427 struct p9_rwalk {
428 	u16 nwqid;
429 	struct p9_qid wqids[16];
430 };
431 
432 struct p9_topen {
433 	u32 fid;
434 	u8 mode;
435 };
436 
437 struct p9_ropen {
438 	struct p9_qid qid;
439 	u32 iounit;
440 };
441 
442 struct p9_tcreate {
443 	u32 fid;
444 	struct p9_str name;
445 	u32 perm;
446 	u8 mode;
447 	struct p9_str extension;
448 };
449 
450 struct p9_rcreate {
451 	struct p9_qid qid;
452 	u32 iounit;
453 };
454 
455 struct p9_tread {
456 	u32 fid;
457 	u64 offset;
458 	u32 count;
459 };
460 
461 struct p9_rread {
462 	u32 count;
463 	u8 *data;
464 };
465 
466 struct p9_twrite {
467 	u32 fid;
468 	u64 offset;
469 	u32 count;
470 	u8 *data;
471 };
472 
473 struct p9_rwrite {
474 	u32 count;
475 };
476 
477 struct p9_tclunk {
478 	u32 fid;
479 };
480 
481 struct p9_rclunk {
482 };
483 
484 struct p9_tremove {
485 	u32 fid;
486 };
487 
488 struct p9_rremove {
489 };
490 
491 struct p9_tstat {
492 	u32 fid;
493 };
494 
495 struct p9_rstat {
496 	struct p9_stat stat;
497 };
498 
499 struct p9_twstat {
500 	u32 fid;
501 	struct p9_stat stat;
502 };
503 
504 struct p9_rwstat {
505 };
506 
507 /**
508  * struct p9_fcall - primary packet structure
509  * @size: prefixed length of the structure
510  * @id: protocol operating identifier of type &p9_msg_t
511  * @tag: transaction id of the request
512  * @sdata: payload
513  * @params: per-operation parameters
514  *
515  * &p9_fcall represents the structure for all 9P RPC
516  * transactions.  Requests are packaged into fcalls, and reponses
517  * must be extracted from them.
518  *
519  * See Also: http://plan9.bell-labs.com/magic/man2html/2/fcall
520  */
521 
522 struct p9_fcall {
523 	u32 size;
524 	u8 id;
525 	u16 tag;
526 	void *sdata;
527 
528 	union {
529 		struct p9_tversion tversion;
530 		struct p9_rversion rversion;
531 		struct p9_tauth tauth;
532 		struct p9_rauth rauth;
533 		struct p9_rerror rerror;
534 		struct p9_tflush tflush;
535 		struct p9_rflush rflush;
536 		struct p9_tattach tattach;
537 		struct p9_rattach rattach;
538 		struct p9_twalk twalk;
539 		struct p9_rwalk rwalk;
540 		struct p9_topen topen;
541 		struct p9_ropen ropen;
542 		struct p9_tcreate tcreate;
543 		struct p9_rcreate rcreate;
544 		struct p9_tread tread;
545 		struct p9_rread rread;
546 		struct p9_twrite twrite;
547 		struct p9_rwrite rwrite;
548 		struct p9_tclunk tclunk;
549 		struct p9_rclunk rclunk;
550 		struct p9_tremove tremove;
551 		struct p9_rremove rremove;
552 		struct p9_tstat tstat;
553 		struct p9_rstat rstat;
554 		struct p9_twstat twstat;
555 		struct p9_rwstat rwstat;
556 	} params;
557 };
558 
559 struct p9_idpool;
560 
561 int p9_deserialize_stat(void *buf, u32 buflen, struct p9_stat *stat,
562 	int dotu);
563 int p9_deserialize_fcall(void *buf, u32 buflen, struct p9_fcall *fc, int dotu);
564 void p9_set_tag(struct p9_fcall *fc, u16 tag);
565 struct p9_fcall *p9_create_tversion(u32 msize, char *version);
566 struct p9_fcall *p9_create_tattach(u32 fid, u32 afid, char *uname,
567 	char *aname, u32 n_uname, int dotu);
568 struct p9_fcall *p9_create_tauth(u32 afid, char *uname, char *aname,
569 	u32 n_uname, int dotu);
570 struct p9_fcall *p9_create_tflush(u16 oldtag);
571 struct p9_fcall *p9_create_twalk(u32 fid, u32 newfid, u16 nwname,
572 	char **wnames);
573 struct p9_fcall *p9_create_topen(u32 fid, u8 mode);
574 struct p9_fcall *p9_create_tcreate(u32 fid, char *name, u32 perm, u8 mode,
575 	char *extension, int dotu);
576 struct p9_fcall *p9_create_tread(u32 fid, u64 offset, u32 count);
577 struct p9_fcall *p9_create_twrite(u32 fid, u64 offset, u32 count,
578 	const char *data);
579 struct p9_fcall *p9_create_twrite_u(u32 fid, u64 offset, u32 count,
580 	const char __user *data);
581 struct p9_fcall *p9_create_tclunk(u32 fid);
582 struct p9_fcall *p9_create_tremove(u32 fid);
583 struct p9_fcall *p9_create_tstat(u32 fid);
584 struct p9_fcall *p9_create_twstat(u32 fid, struct p9_wstat *wstat,
585 	int dotu);
586 
587 int p9_printfcall(char *buf, int buflen, struct p9_fcall *fc, int dotu);
588 int p9_errstr2errno(char *errstr, int len);
589 
590 struct p9_idpool *p9_idpool_create(void);
591 void p9_idpool_destroy(struct p9_idpool *);
592 int p9_idpool_get(struct p9_idpool *p);
593 void p9_idpool_put(int id, struct p9_idpool *p);
594 int p9_idpool_check(int id, struct p9_idpool *p);
595 
596 int p9_error_init(void);
597 int p9_errstr2errno(char *, int);
598 int p9_trans_fd_init(void);
599 #endif /* NET_9P_H */
600