xref: /openbmc/linux/include/net/9p/9p.h (revision 0646c28b)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * 9P protocol definitions.
4  *
5  *  Copyright (C) 2005 by Latchesar Ionkov <lucho@ionkov.net>
6  *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
7  *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
8  */
9 
10 #ifndef NET_9P_H
11 #define NET_9P_H
12 
13 /**
14  * enum p9_debug_flags - bits for mount time debug parameter
15  * @P9_DEBUG_ERROR: more verbose error messages including original error string
16  * @P9_DEBUG_9P: 9P protocol tracing
17  * @P9_DEBUG_VFS: VFS API tracing
18  * @P9_DEBUG_CONV: protocol conversion tracing
19  * @P9_DEBUG_MUX: trace management of concurrent transactions
20  * @P9_DEBUG_TRANS: transport tracing
21  * @P9_DEBUG_SLABS: memory management tracing
22  * @P9_DEBUG_FCALL: verbose dump of protocol messages
23  * @P9_DEBUG_FID: fid allocation/deallocation tracking
24  * @P9_DEBUG_PKT: packet marshalling/unmarshalling
25  * @P9_DEBUG_FSC: FS-cache tracing
26  * @P9_DEBUG_VPKT: Verbose packet debugging (full packet dump)
27  *
28  * These flags are passed at mount time to turn on various levels of
29  * verbosity and tracing which will be output to the system logs.
30  */
31 
32 enum p9_debug_flags {
33 	P9_DEBUG_ERROR =	(1<<0),
34 	P9_DEBUG_9P =		(1<<2),
35 	P9_DEBUG_VFS =		(1<<3),
36 	P9_DEBUG_CONV =		(1<<4),
37 	P9_DEBUG_MUX =		(1<<5),
38 	P9_DEBUG_TRANS =	(1<<6),
39 	P9_DEBUG_SLABS =	(1<<7),
40 	P9_DEBUG_FCALL =	(1<<8),
41 	P9_DEBUG_FID =		(1<<9),
42 	P9_DEBUG_PKT =		(1<<10),
43 	P9_DEBUG_FSC =		(1<<11),
44 	P9_DEBUG_VPKT =		(1<<12),
45 };
46 
47 #ifdef CONFIG_NET_9P_DEBUG
48 extern unsigned int p9_debug_level;
49 __printf(3, 4)
50 void _p9_debug(enum p9_debug_flags level, const char *func,
51 	       const char *fmt, ...);
52 #define p9_debug(level, fmt, ...)			\
53 	_p9_debug(level, __func__, fmt, ##__VA_ARGS__)
54 #else
55 #define p9_debug(level, fmt, ...)			\
56 	no_printk(fmt, ##__VA_ARGS__)
57 #endif
58 
59 /**
60  * enum p9_msg_t - 9P message types
61  * @P9_TLERROR: not used
62  * @P9_RLERROR: response for any failed request for 9P2000.L
63  * @P9_TSTATFS: file system status request
64  * @P9_RSTATFS: file system status response
65  * @P9_TSYMLINK: make symlink request
66  * @P9_RSYMLINK: make symlink response
67  * @P9_TMKNOD: create a special file object request
68  * @P9_RMKNOD: create a special file object response
69  * @P9_TLCREATE: prepare a handle for I/O on an new file for 9P2000.L
70  * @P9_RLCREATE: response with file access information for 9P2000.L
71  * @P9_TRENAME: rename request
72  * @P9_RRENAME: rename response
73  * @P9_TMKDIR: create a directory request
74  * @P9_RMKDIR: create a directory response
75  * @P9_TVERSION: version handshake request
76  * @P9_RVERSION: version handshake response
77  * @P9_TAUTH: request to establish authentication channel
78  * @P9_RAUTH: response with authentication information
79  * @P9_TATTACH: establish user access to file service
80  * @P9_RATTACH: response with top level handle to file hierarchy
81  * @P9_TERROR: not used
82  * @P9_RERROR: response for any failed request
83  * @P9_TFLUSH: request to abort a previous request
84  * @P9_RFLUSH: response when previous request has been cancelled
85  * @P9_TWALK: descend a directory hierarchy
86  * @P9_RWALK: response with new handle for position within hierarchy
87  * @P9_TOPEN: prepare a handle for I/O on an existing file
88  * @P9_ROPEN: response with file access information
89  * @P9_TCREATE: prepare a handle for I/O on a new file
90  * @P9_RCREATE: response with file access information
91  * @P9_TREAD: request to transfer data from a file or directory
92  * @P9_RREAD: response with data requested
93  * @P9_TWRITE: reuqest to transfer data to a file
94  * @P9_RWRITE: response with out much data was transferred to file
95  * @P9_TCLUNK: forget about a handle to an entity within the file system
96  * @P9_RCLUNK: response when server has forgotten about the handle
97  * @P9_TREMOVE: request to remove an entity from the hierarchy
98  * @P9_RREMOVE: response when server has removed the entity
99  * @P9_TSTAT: request file entity attributes
100  * @P9_RSTAT: response with file entity attributes
101  * @P9_TWSTAT: request to update file entity attributes
102  * @P9_RWSTAT: response when file entity attributes are updated
103  *
104  * There are 14 basic operations in 9P2000, paired as
105  * requests and responses.  The one special case is ERROR
106  * as there is no @P9_TERROR request for clients to transmit to
107  * the server, but the server may respond to any other request
108  * with an @P9_RERROR.
109  *
110  * See Also: http://plan9.bell-labs.com/sys/man/5/INDEX.html
111  */
112 
113 enum p9_msg_t {
114 	P9_TLERROR = 6,
115 	P9_RLERROR,
116 	P9_TSTATFS = 8,
117 	P9_RSTATFS,
118 	P9_TLOPEN = 12,
119 	P9_RLOPEN,
120 	P9_TLCREATE = 14,
121 	P9_RLCREATE,
122 	P9_TSYMLINK = 16,
123 	P9_RSYMLINK,
124 	P9_TMKNOD = 18,
125 	P9_RMKNOD,
126 	P9_TRENAME = 20,
127 	P9_RRENAME,
128 	P9_TREADLINK = 22,
129 	P9_RREADLINK,
130 	P9_TGETATTR = 24,
131 	P9_RGETATTR,
132 	P9_TSETATTR = 26,
133 	P9_RSETATTR,
134 	P9_TXATTRWALK = 30,
135 	P9_RXATTRWALK,
136 	P9_TXATTRCREATE = 32,
137 	P9_RXATTRCREATE,
138 	P9_TREADDIR = 40,
139 	P9_RREADDIR,
140 	P9_TFSYNC = 50,
141 	P9_RFSYNC,
142 	P9_TLOCK = 52,
143 	P9_RLOCK,
144 	P9_TGETLOCK = 54,
145 	P9_RGETLOCK,
146 	P9_TLINK = 70,
147 	P9_RLINK,
148 	P9_TMKDIR = 72,
149 	P9_RMKDIR,
150 	P9_TRENAMEAT = 74,
151 	P9_RRENAMEAT,
152 	P9_TUNLINKAT = 76,
153 	P9_RUNLINKAT,
154 	P9_TVERSION = 100,
155 	P9_RVERSION,
156 	P9_TAUTH = 102,
157 	P9_RAUTH,
158 	P9_TATTACH = 104,
159 	P9_RATTACH,
160 	P9_TERROR = 106,
161 	P9_RERROR,
162 	P9_TFLUSH = 108,
163 	P9_RFLUSH,
164 	P9_TWALK = 110,
165 	P9_RWALK,
166 	P9_TOPEN = 112,
167 	P9_ROPEN,
168 	P9_TCREATE = 114,
169 	P9_RCREATE,
170 	P9_TREAD = 116,
171 	P9_RREAD,
172 	P9_TWRITE = 118,
173 	P9_RWRITE,
174 	P9_TCLUNK = 120,
175 	P9_RCLUNK,
176 	P9_TREMOVE = 122,
177 	P9_RREMOVE,
178 	P9_TSTAT = 124,
179 	P9_RSTAT,
180 	P9_TWSTAT = 126,
181 	P9_RWSTAT,
182 };
183 
184 /**
185  * enum p9_open_mode_t - 9P open modes
186  * @P9_OREAD: open file for reading only
187  * @P9_OWRITE: open file for writing only
188  * @P9_ORDWR: open file for reading or writing
189  * @P9_OEXEC: open file for execution
190  * @P9_OTRUNC: truncate file to zero-length before opening it
191  * @P9_OREXEC: close the file when an exec(2) system call is made
192  * @P9_ORCLOSE: remove the file when the file is closed
193  * @P9_OAPPEND: open the file and seek to the end
194  * @P9_OEXCL: only create a file, do not open it
195  *
196  * 9P open modes differ slightly from Posix standard modes.
197  * In particular, there are extra modes which specify different
198  * semantic behaviors than may be available on standard Posix
199  * systems.  For example, @P9_OREXEC and @P9_ORCLOSE are modes that
200  * most likely will not be issued from the Linux VFS client, but may
201  * be supported by servers.
202  *
203  * See Also: http://plan9.bell-labs.com/magic/man2html/2/open
204  */
205 
206 enum p9_open_mode_t {
207 	P9_OREAD = 0x00,
208 	P9_OWRITE = 0x01,
209 	P9_ORDWR = 0x02,
210 	P9_OEXEC = 0x03,
211 	P9_OTRUNC = 0x10,
212 	P9_OREXEC = 0x20,
213 	P9_ORCLOSE = 0x40,
214 	P9_OAPPEND = 0x80,
215 	P9_OEXCL = 0x1000,
216 };
217 
218 /**
219  * enum p9_perm_t - 9P permissions
220  * @P9_DMDIR: mode bit for directories
221  * @P9_DMAPPEND: mode bit for is append-only
222  * @P9_DMEXCL: mode bit for excluse use (only one open handle allowed)
223  * @P9_DMMOUNT: mode bit for mount points
224  * @P9_DMAUTH: mode bit for authentication file
225  * @P9_DMTMP: mode bit for non-backed-up files
226  * @P9_DMSYMLINK: mode bit for symbolic links (9P2000.u)
227  * @P9_DMLINK: mode bit for hard-link (9P2000.u)
228  * @P9_DMDEVICE: mode bit for device files (9P2000.u)
229  * @P9_DMNAMEDPIPE: mode bit for named pipe (9P2000.u)
230  * @P9_DMSOCKET: mode bit for socket (9P2000.u)
231  * @P9_DMSETUID: mode bit for setuid (9P2000.u)
232  * @P9_DMSETGID: mode bit for setgid (9P2000.u)
233  * @P9_DMSETVTX: mode bit for sticky bit (9P2000.u)
234  *
235  * 9P permissions differ slightly from Posix standard modes.
236  *
237  * See Also: http://plan9.bell-labs.com/magic/man2html/2/stat
238  */
239 enum p9_perm_t {
240 	P9_DMDIR = 0x80000000,
241 	P9_DMAPPEND = 0x40000000,
242 	P9_DMEXCL = 0x20000000,
243 	P9_DMMOUNT = 0x10000000,
244 	P9_DMAUTH = 0x08000000,
245 	P9_DMTMP = 0x04000000,
246 /* 9P2000.u extensions */
247 	P9_DMSYMLINK = 0x02000000,
248 	P9_DMLINK = 0x01000000,
249 	P9_DMDEVICE = 0x00800000,
250 	P9_DMNAMEDPIPE = 0x00200000,
251 	P9_DMSOCKET = 0x00100000,
252 	P9_DMSETUID = 0x00080000,
253 	P9_DMSETGID = 0x00040000,
254 	P9_DMSETVTX = 0x00010000,
255 };
256 
257 /* 9p2000.L open flags */
258 #define P9_DOTL_RDONLY        00000000
259 #define P9_DOTL_WRONLY        00000001
260 #define P9_DOTL_RDWR          00000002
261 #define P9_DOTL_NOACCESS      00000003
262 #define P9_DOTL_CREATE        00000100
263 #define P9_DOTL_EXCL          00000200
264 #define P9_DOTL_NOCTTY        00000400
265 #define P9_DOTL_TRUNC         00001000
266 #define P9_DOTL_APPEND        00002000
267 #define P9_DOTL_NONBLOCK      00004000
268 #define P9_DOTL_DSYNC         00010000
269 #define P9_DOTL_FASYNC        00020000
270 #define P9_DOTL_DIRECT        00040000
271 #define P9_DOTL_LARGEFILE     00100000
272 #define P9_DOTL_DIRECTORY     00200000
273 #define P9_DOTL_NOFOLLOW      00400000
274 #define P9_DOTL_NOATIME       01000000
275 #define P9_DOTL_CLOEXEC       02000000
276 #define P9_DOTL_SYNC          04000000
277 
278 /* 9p2000.L at flags */
279 #define P9_DOTL_AT_REMOVEDIR		0x200
280 
281 /* 9p2000.L lock type */
282 #define P9_LOCK_TYPE_RDLCK 0
283 #define P9_LOCK_TYPE_WRLCK 1
284 #define P9_LOCK_TYPE_UNLCK 2
285 
286 /**
287  * enum p9_qid_t - QID types
288  * @P9_QTDIR: directory
289  * @P9_QTAPPEND: append-only
290  * @P9_QTEXCL: excluse use (only one open handle allowed)
291  * @P9_QTMOUNT: mount points
292  * @P9_QTAUTH: authentication file
293  * @P9_QTTMP: non-backed-up files
294  * @P9_QTSYMLINK: symbolic links (9P2000.u)
295  * @P9_QTLINK: hard-link (9P2000.u)
296  * @P9_QTFILE: normal files
297  *
298  * QID types are a subset of permissions - they are primarily
299  * used to differentiate semantics for a file system entity via
300  * a jump-table.  Their value is also the most significant 16 bits
301  * of the permission_t
302  *
303  * See Also: http://plan9.bell-labs.com/magic/man2html/2/stat
304  */
305 enum p9_qid_t {
306 	P9_QTDIR = 0x80,
307 	P9_QTAPPEND = 0x40,
308 	P9_QTEXCL = 0x20,
309 	P9_QTMOUNT = 0x10,
310 	P9_QTAUTH = 0x08,
311 	P9_QTTMP = 0x04,
312 	P9_QTSYMLINK = 0x02,
313 	P9_QTLINK = 0x01,
314 	P9_QTFILE = 0x00,
315 };
316 
317 /* 9P Magic Numbers */
318 #define P9_NOTAG	((u16)(~0))
319 #define P9_NOFID	((u32)(~0))
320 #define P9_MAXWELEM	16
321 
322 /* Minimal header size: size[4] type[1] tag[2] */
323 #define P9_HDRSZ	7
324 
325 /* ample room for Twrite/Rread header */
326 #define P9_IOHDRSZ	24
327 
328 /* Room for readdir header */
329 #define P9_READDIRHDRSZ	24
330 
331 /* size of header for zero copy read/write */
332 #define P9_ZC_HDR_SZ 4096
333 
334 /* maximum length of an error string */
335 #define P9_ERRMAX 128
336 
337 /**
338  * struct p9_qid - file system entity information
339  * @type: 8-bit type &p9_qid_t
340  * @version: 16-bit monotonically incrementing version number
341  * @path: 64-bit per-server-unique ID for a file system element
342  *
343  * qids are identifiers used by 9P servers to track file system
344  * entities.  The type is used to differentiate semantics for operations
345  * on the entity (ie. read means something different on a directory than
346  * on a file).  The path provides a server unique index for an entity
347  * (roughly analogous to an inode number), while the version is updated
348  * every time a file is modified and can be used to maintain cache
349  * coherency between clients and serves.
350  * Servers will often differentiate purely synthetic entities by setting
351  * their version to 0, signaling that they should never be cached and
352  * should be accessed synchronously.
353  *
354  * See Also://plan9.bell-labs.com/magic/man2html/2/stat
355  */
356 
357 struct p9_qid {
358 	u8 type;
359 	u32 version;
360 	u64 path;
361 };
362 
363 /**
364  * struct p9_wstat - file system metadata information
365  * @size: length prefix for this stat structure instance
366  * @type: the type of the server (equivalent to a major number)
367  * @dev: the sub-type of the server (equivalent to a minor number)
368  * @qid: unique id from the server of type &p9_qid
369  * @mode: Plan 9 format permissions of type &p9_perm_t
370  * @atime: Last access/read time
371  * @mtime: Last modify/write time
372  * @length: file length
373  * @name: last element of path (aka filename)
374  * @uid: owner name
375  * @gid: group owner
376  * @muid: last modifier
377  * @extension: area used to encode extended UNIX support
378  * @n_uid: numeric user id of owner (part of 9p2000.u extension)
379  * @n_gid: numeric group id (part of 9p2000.u extension)
380  * @n_muid: numeric user id of laster modifier (part of 9p2000.u extension)
381  *
382  * See Also: http://plan9.bell-labs.com/magic/man2html/2/stat
383  */
384 
385 struct p9_wstat {
386 	u16 size;
387 	u16 type;
388 	u32 dev;
389 	struct p9_qid qid;
390 	u32 mode;
391 	u32 atime;
392 	u32 mtime;
393 	u64 length;
394 	const char *name;
395 	const char *uid;
396 	const char *gid;
397 	const char *muid;
398 	char *extension;	/* 9p2000.u extensions */
399 	kuid_t n_uid;		/* 9p2000.u extensions */
400 	kgid_t n_gid;		/* 9p2000.u extensions */
401 	kuid_t n_muid;		/* 9p2000.u extensions */
402 };
403 
404 struct p9_stat_dotl {
405 	u64 st_result_mask;
406 	struct p9_qid qid;
407 	u32 st_mode;
408 	kuid_t st_uid;
409 	kgid_t st_gid;
410 	u64 st_nlink;
411 	u64 st_rdev;
412 	u64 st_size;
413 	u64 st_blksize;
414 	u64 st_blocks;
415 	u64 st_atime_sec;
416 	u64 st_atime_nsec;
417 	u64 st_mtime_sec;
418 	u64 st_mtime_nsec;
419 	u64 st_ctime_sec;
420 	u64 st_ctime_nsec;
421 	u64 st_btime_sec;
422 	u64 st_btime_nsec;
423 	u64 st_gen;
424 	u64 st_data_version;
425 };
426 
427 #define P9_STATS_MODE		0x00000001ULL
428 #define P9_STATS_NLINK		0x00000002ULL
429 #define P9_STATS_UID		0x00000004ULL
430 #define P9_STATS_GID		0x00000008ULL
431 #define P9_STATS_RDEV		0x00000010ULL
432 #define P9_STATS_ATIME		0x00000020ULL
433 #define P9_STATS_MTIME		0x00000040ULL
434 #define P9_STATS_CTIME		0x00000080ULL
435 #define P9_STATS_INO		0x00000100ULL
436 #define P9_STATS_SIZE		0x00000200ULL
437 #define P9_STATS_BLOCKS		0x00000400ULL
438 
439 #define P9_STATS_BTIME		0x00000800ULL
440 #define P9_STATS_GEN		0x00001000ULL
441 #define P9_STATS_DATA_VERSION	0x00002000ULL
442 
443 #define P9_STATS_BASIC		0x000007ffULL /* Mask for fields up to BLOCKS */
444 #define P9_STATS_ALL		0x00003fffULL /* Mask for All fields above */
445 
446 /**
447  * struct p9_iattr_dotl - P9 inode attribute for setattr
448  * @valid: bitfield specifying which fields are valid
449  *         same as in struct iattr
450  * @mode: File permission bits
451  * @uid: user id of owner
452  * @gid: group id
453  * @size: File size
454  * @atime_sec: Last access time, seconds
455  * @atime_nsec: Last access time, nanoseconds
456  * @mtime_sec: Last modification time, seconds
457  * @mtime_nsec: Last modification time, nanoseconds
458  */
459 
460 struct p9_iattr_dotl {
461 	u32 valid;
462 	u32 mode;
463 	kuid_t uid;
464 	kgid_t gid;
465 	u64 size;
466 	u64 atime_sec;
467 	u64 atime_nsec;
468 	u64 mtime_sec;
469 	u64 mtime_nsec;
470 };
471 
472 #define P9_LOCK_SUCCESS 0
473 #define P9_LOCK_BLOCKED 1
474 #define P9_LOCK_ERROR 2
475 #define P9_LOCK_GRACE 3
476 
477 #define P9_LOCK_FLAGS_BLOCK 1
478 #define P9_LOCK_FLAGS_RECLAIM 2
479 
480 /* struct p9_flock: POSIX lock structure
481  * @type - type of lock
482  * @flags - lock flags
483  * @start - starting offset of the lock
484  * @length - number of bytes
485  * @proc_id - process id which wants to take lock
486  * @client_id - client id
487  */
488 
489 struct p9_flock {
490 	u8 type;
491 	u32 flags;
492 	u64 start;
493 	u64 length;
494 	u32 proc_id;
495 	char *client_id;
496 };
497 
498 /* struct p9_getlock: getlock structure
499  * @type - type of lock
500  * @start - starting offset of the lock
501  * @length - number of bytes
502  * @proc_id - process id which wants to take lock
503  * @client_id - client id
504  */
505 
506 struct p9_getlock {
507 	u8 type;
508 	u64 start;
509 	u64 length;
510 	u32 proc_id;
511 	char *client_id;
512 };
513 
514 struct p9_rstatfs {
515 	u32 type;
516 	u32 bsize;
517 	u64 blocks;
518 	u64 bfree;
519 	u64 bavail;
520 	u64 files;
521 	u64 ffree;
522 	u64 fsid;
523 	u32 namelen;
524 };
525 
526 /**
527  * struct p9_fcall - primary packet structure
528  * @size: prefixed length of the structure
529  * @id: protocol operating identifier of type &p9_msg_t
530  * @tag: transaction id of the request
531  * @offset: used by marshalling routines to track current position in buffer
532  * @capacity: used by marshalling routines to track total malloc'd capacity
533  * @sdata: payload
534  *
535  * &p9_fcall represents the structure for all 9P RPC
536  * transactions.  Requests are packaged into fcalls, and reponses
537  * must be extracted from them.
538  *
539  * See Also: http://plan9.bell-labs.com/magic/man2html/2/fcall
540  */
541 
542 struct p9_fcall {
543 	u32 size;
544 	u8 id;
545 	u16 tag;
546 
547 	size_t offset;
548 	size_t capacity;
549 
550 	struct kmem_cache *cache;
551 	u8 *sdata;
552 };
553 
554 int p9_errstr2errno(char *errstr, int len);
555 
556 int p9_error_init(void);
557 #endif /* NET_9P_H */
558