xref: /openbmc/linux/include/net/9p/9p.h (revision 0545810f)
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 	P9_DEBUG_CACHE =	(1<<13),
46 	P9_DEBUG_MMAP =		(1<<14),
47 };
48 
49 #ifdef CONFIG_NET_9P_DEBUG
50 extern unsigned int p9_debug_level;
51 __printf(3, 4)
52 void _p9_debug(enum p9_debug_flags level, const char *func,
53 	       const char *fmt, ...);
54 #define p9_debug(level, fmt, ...)			\
55 	_p9_debug(level, __func__, fmt, ##__VA_ARGS__)
56 #else
57 #define p9_debug(level, fmt, ...)			\
58 	no_printk(fmt, ##__VA_ARGS__)
59 #endif
60 
61 /**
62  * enum p9_msg_t - 9P message types
63  * @P9_TLERROR: not used
64  * @P9_RLERROR: response for any failed request for 9P2000.L
65  * @P9_TSTATFS: file system status request
66  * @P9_RSTATFS: file system status response
67  * @P9_TSYMLINK: make symlink request
68  * @P9_RSYMLINK: make symlink response
69  * @P9_TMKNOD: create a special file object request
70  * @P9_RMKNOD: create a special file object response
71  * @P9_TLCREATE: prepare a handle for I/O on an new file for 9P2000.L
72  * @P9_RLCREATE: response with file access information for 9P2000.L
73  * @P9_TRENAME: rename request
74  * @P9_RRENAME: rename response
75  * @P9_TMKDIR: create a directory request
76  * @P9_RMKDIR: create a directory response
77  * @P9_TVERSION: version handshake request
78  * @P9_RVERSION: version handshake response
79  * @P9_TAUTH: request to establish authentication channel
80  * @P9_RAUTH: response with authentication information
81  * @P9_TATTACH: establish user access to file service
82  * @P9_RATTACH: response with top level handle to file hierarchy
83  * @P9_TERROR: not used
84  * @P9_RERROR: response for any failed request
85  * @P9_TFLUSH: request to abort a previous request
86  * @P9_RFLUSH: response when previous request has been cancelled
87  * @P9_TWALK: descend a directory hierarchy
88  * @P9_RWALK: response with new handle for position within hierarchy
89  * @P9_TOPEN: prepare a handle for I/O on an existing file
90  * @P9_ROPEN: response with file access information
91  * @P9_TCREATE: prepare a handle for I/O on a new file
92  * @P9_RCREATE: response with file access information
93  * @P9_TREAD: request to transfer data from a file or directory
94  * @P9_RREAD: response with data requested
95  * @P9_TWRITE: reuqest to transfer data to a file
96  * @P9_RWRITE: response with out much data was transferred to file
97  * @P9_TCLUNK: forget about a handle to an entity within the file system
98  * @P9_RCLUNK: response when server has forgotten about the handle
99  * @P9_TREMOVE: request to remove an entity from the hierarchy
100  * @P9_RREMOVE: response when server has removed the entity
101  * @P9_TSTAT: request file entity attributes
102  * @P9_RSTAT: response with file entity attributes
103  * @P9_TWSTAT: request to update file entity attributes
104  * @P9_RWSTAT: response when file entity attributes are updated
105  *
106  * There are 14 basic operations in 9P2000, paired as
107  * requests and responses.  The one special case is ERROR
108  * as there is no @P9_TERROR request for clients to transmit to
109  * the server, but the server may respond to any other request
110  * with an @P9_RERROR.
111  *
112  * See Also: http://plan9.bell-labs.com/sys/man/5/INDEX.html
113  */
114 
115 enum p9_msg_t {
116 	P9_TLERROR = 6,
117 	P9_RLERROR,
118 	P9_TSTATFS = 8,
119 	P9_RSTATFS,
120 	P9_TLOPEN = 12,
121 	P9_RLOPEN,
122 	P9_TLCREATE = 14,
123 	P9_RLCREATE,
124 	P9_TSYMLINK = 16,
125 	P9_RSYMLINK,
126 	P9_TMKNOD = 18,
127 	P9_RMKNOD,
128 	P9_TRENAME = 20,
129 	P9_RRENAME,
130 	P9_TREADLINK = 22,
131 	P9_RREADLINK,
132 	P9_TGETATTR = 24,
133 	P9_RGETATTR,
134 	P9_TSETATTR = 26,
135 	P9_RSETATTR,
136 	P9_TXATTRWALK = 30,
137 	P9_RXATTRWALK,
138 	P9_TXATTRCREATE = 32,
139 	P9_RXATTRCREATE,
140 	P9_TREADDIR = 40,
141 	P9_RREADDIR,
142 	P9_TFSYNC = 50,
143 	P9_RFSYNC,
144 	P9_TLOCK = 52,
145 	P9_RLOCK,
146 	P9_TGETLOCK = 54,
147 	P9_RGETLOCK,
148 	P9_TLINK = 70,
149 	P9_RLINK,
150 	P9_TMKDIR = 72,
151 	P9_RMKDIR,
152 	P9_TRENAMEAT = 74,
153 	P9_RRENAMEAT,
154 	P9_TUNLINKAT = 76,
155 	P9_RUNLINKAT,
156 	P9_TVERSION = 100,
157 	P9_RVERSION,
158 	P9_TAUTH = 102,
159 	P9_RAUTH,
160 	P9_TATTACH = 104,
161 	P9_RATTACH,
162 	P9_TERROR = 106,
163 	P9_RERROR,
164 	P9_TFLUSH = 108,
165 	P9_RFLUSH,
166 	P9_TWALK = 110,
167 	P9_RWALK,
168 	P9_TOPEN = 112,
169 	P9_ROPEN,
170 	P9_TCREATE = 114,
171 	P9_RCREATE,
172 	P9_TREAD = 116,
173 	P9_RREAD,
174 	P9_TWRITE = 118,
175 	P9_RWRITE,
176 	P9_TCLUNK = 120,
177 	P9_RCLUNK,
178 	P9_TREMOVE = 122,
179 	P9_RREMOVE,
180 	P9_TSTAT = 124,
181 	P9_RSTAT,
182 	P9_TWSTAT = 126,
183 	P9_RWSTAT,
184 };
185 
186 /**
187  * enum p9_open_mode_t - 9P open modes
188  * @P9_OREAD: open file for reading only
189  * @P9_OWRITE: open file for writing only
190  * @P9_ORDWR: open file for reading or writing
191  * @P9_OEXEC: open file for execution
192  * @P9_OTRUNC: truncate file to zero-length before opening it
193  * @P9_OREXEC: close the file when an exec(2) system call is made
194  * @P9_ORCLOSE: remove the file when the file is closed
195  * @P9_OAPPEND: open the file and seek to the end
196  * @P9_OEXCL: only create a file, do not open it
197  *
198  * 9P open modes differ slightly from Posix standard modes.
199  * In particular, there are extra modes which specify different
200  * semantic behaviors than may be available on standard Posix
201  * systems.  For example, @P9_OREXEC and @P9_ORCLOSE are modes that
202  * most likely will not be issued from the Linux VFS client, but may
203  * be supported by servers.
204  *
205  * See Also: http://plan9.bell-labs.com/magic/man2html/2/open
206  */
207 
208 enum p9_open_mode_t {
209 	P9_OREAD = 0x00,
210 	P9_OWRITE = 0x01,
211 	P9_ORDWR = 0x02,
212 	P9_OEXEC = 0x03,
213 	P9_OTRUNC = 0x10,
214 	P9_OREXEC = 0x20,
215 	P9_ORCLOSE = 0x40,
216 	P9_OAPPEND = 0x80,
217 	P9_OEXCL = 0x1000,
218 	P9L_MODE_MASK = 0x1FFF, /* don't send anything under this to server */
219 	P9L_DIRECT = 0x2000, /* cache disabled */
220 	P9L_NOWRITECACHE = 0x4000, /* no write caching  */
221 	P9L_LOOSE = 0x8000, /* loose cache */
222 };
223 
224 /**
225  * enum p9_perm_t - 9P permissions
226  * @P9_DMDIR: mode bit for directories
227  * @P9_DMAPPEND: mode bit for is append-only
228  * @P9_DMEXCL: mode bit for excluse use (only one open handle allowed)
229  * @P9_DMMOUNT: mode bit for mount points
230  * @P9_DMAUTH: mode bit for authentication file
231  * @P9_DMTMP: mode bit for non-backed-up files
232  * @P9_DMSYMLINK: mode bit for symbolic links (9P2000.u)
233  * @P9_DMLINK: mode bit for hard-link (9P2000.u)
234  * @P9_DMDEVICE: mode bit for device files (9P2000.u)
235  * @P9_DMNAMEDPIPE: mode bit for named pipe (9P2000.u)
236  * @P9_DMSOCKET: mode bit for socket (9P2000.u)
237  * @P9_DMSETUID: mode bit for setuid (9P2000.u)
238  * @P9_DMSETGID: mode bit for setgid (9P2000.u)
239  * @P9_DMSETVTX: mode bit for sticky bit (9P2000.u)
240  *
241  * 9P permissions differ slightly from Posix standard modes.
242  *
243  * See Also: http://plan9.bell-labs.com/magic/man2html/2/stat
244  */
245 enum p9_perm_t {
246 	P9_DMDIR = 0x80000000,
247 	P9_DMAPPEND = 0x40000000,
248 	P9_DMEXCL = 0x20000000,
249 	P9_DMMOUNT = 0x10000000,
250 	P9_DMAUTH = 0x08000000,
251 	P9_DMTMP = 0x04000000,
252 /* 9P2000.u extensions */
253 	P9_DMSYMLINK = 0x02000000,
254 	P9_DMLINK = 0x01000000,
255 	P9_DMDEVICE = 0x00800000,
256 	P9_DMNAMEDPIPE = 0x00200000,
257 	P9_DMSOCKET = 0x00100000,
258 	P9_DMSETUID = 0x00080000,
259 	P9_DMSETGID = 0x00040000,
260 	P9_DMSETVTX = 0x00010000,
261 };
262 
263 /* 9p2000.L open flags */
264 #define P9_DOTL_RDONLY        00000000
265 #define P9_DOTL_WRONLY        00000001
266 #define P9_DOTL_RDWR          00000002
267 #define P9_DOTL_NOACCESS      00000003
268 #define P9_DOTL_CREATE        00000100
269 #define P9_DOTL_EXCL          00000200
270 #define P9_DOTL_NOCTTY        00000400
271 #define P9_DOTL_TRUNC         00001000
272 #define P9_DOTL_APPEND        00002000
273 #define P9_DOTL_NONBLOCK      00004000
274 #define P9_DOTL_DSYNC         00010000
275 #define P9_DOTL_FASYNC        00020000
276 #define P9_DOTL_DIRECT        00040000
277 #define P9_DOTL_LARGEFILE     00100000
278 #define P9_DOTL_DIRECTORY     00200000
279 #define P9_DOTL_NOFOLLOW      00400000
280 #define P9_DOTL_NOATIME       01000000
281 #define P9_DOTL_CLOEXEC       02000000
282 #define P9_DOTL_SYNC          04000000
283 
284 /* 9p2000.L at flags */
285 #define P9_DOTL_AT_REMOVEDIR		0x200
286 
287 /* 9p2000.L lock type */
288 #define P9_LOCK_TYPE_RDLCK 0
289 #define P9_LOCK_TYPE_WRLCK 1
290 #define P9_LOCK_TYPE_UNLCK 2
291 
292 /**
293  * enum p9_qid_t - QID types
294  * @P9_QTDIR: directory
295  * @P9_QTAPPEND: append-only
296  * @P9_QTEXCL: excluse use (only one open handle allowed)
297  * @P9_QTMOUNT: mount points
298  * @P9_QTAUTH: authentication file
299  * @P9_QTTMP: non-backed-up files
300  * @P9_QTSYMLINK: symbolic links (9P2000.u)
301  * @P9_QTLINK: hard-link (9P2000.u)
302  * @P9_QTFILE: normal files
303  *
304  * QID types are a subset of permissions - they are primarily
305  * used to differentiate semantics for a file system entity via
306  * a jump-table.  Their value is also the most significant 16 bits
307  * of the permission_t
308  *
309  * See Also: http://plan9.bell-labs.com/magic/man2html/2/stat
310  */
311 enum p9_qid_t {
312 	P9_QTDIR = 0x80,
313 	P9_QTAPPEND = 0x40,
314 	P9_QTEXCL = 0x20,
315 	P9_QTMOUNT = 0x10,
316 	P9_QTAUTH = 0x08,
317 	P9_QTTMP = 0x04,
318 	P9_QTSYMLINK = 0x02,
319 	P9_QTLINK = 0x01,
320 	P9_QTFILE = 0x00,
321 };
322 
323 /* 9P Magic Numbers */
324 #define P9_NOTAG	((u16)(~0))
325 #define P9_NOFID	((u32)(~0))
326 #define P9_MAXWELEM	16
327 
328 /* Minimal header size: size[4] type[1] tag[2] */
329 #define P9_HDRSZ	7
330 
331 /* ample room for Twrite/Rread header */
332 #define P9_IOHDRSZ	24
333 
334 /* Room for readdir header */
335 #define P9_READDIRHDRSZ	24
336 
337 /* size of header for zero copy read/write */
338 #define P9_ZC_HDR_SZ 4096
339 
340 /* maximum length of an error string */
341 #define P9_ERRMAX 128
342 
343 /**
344  * struct p9_qid - file system entity information
345  * @type: 8-bit type &p9_qid_t
346  * @version: 16-bit monotonically incrementing version number
347  * @path: 64-bit per-server-unique ID for a file system element
348  *
349  * qids are identifiers used by 9P servers to track file system
350  * entities.  The type is used to differentiate semantics for operations
351  * on the entity (ie. read means something different on a directory than
352  * on a file).  The path provides a server unique index for an entity
353  * (roughly analogous to an inode number), while the version is updated
354  * every time a file is modified and can be used to maintain cache
355  * coherency between clients and serves.
356  * Servers will often differentiate purely synthetic entities by setting
357  * their version to 0, signaling that they should never be cached and
358  * should be accessed synchronously.
359  *
360  * See Also://plan9.bell-labs.com/magic/man2html/2/stat
361  */
362 
363 struct p9_qid {
364 	u8 type;
365 	u32 version;
366 	u64 path;
367 };
368 
369 /**
370  * struct p9_wstat - file system metadata information
371  * @size: length prefix for this stat structure instance
372  * @type: the type of the server (equivalent to a major number)
373  * @dev: the sub-type of the server (equivalent to a minor number)
374  * @qid: unique id from the server of type &p9_qid
375  * @mode: Plan 9 format permissions of type &p9_perm_t
376  * @atime: Last access/read time
377  * @mtime: Last modify/write time
378  * @length: file length
379  * @name: last element of path (aka filename)
380  * @uid: owner name
381  * @gid: group owner
382  * @muid: last modifier
383  * @extension: area used to encode extended UNIX support
384  * @n_uid: numeric user id of owner (part of 9p2000.u extension)
385  * @n_gid: numeric group id (part of 9p2000.u extension)
386  * @n_muid: numeric user id of laster modifier (part of 9p2000.u extension)
387  *
388  * See Also: http://plan9.bell-labs.com/magic/man2html/2/stat
389  */
390 
391 struct p9_wstat {
392 	u16 size;
393 	u16 type;
394 	u32 dev;
395 	struct p9_qid qid;
396 	u32 mode;
397 	u32 atime;
398 	u32 mtime;
399 	u64 length;
400 	const char *name;
401 	const char *uid;
402 	const char *gid;
403 	const char *muid;
404 	char *extension;	/* 9p2000.u extensions */
405 	kuid_t n_uid;		/* 9p2000.u extensions */
406 	kgid_t n_gid;		/* 9p2000.u extensions */
407 	kuid_t n_muid;		/* 9p2000.u extensions */
408 };
409 
410 struct p9_stat_dotl {
411 	u64 st_result_mask;
412 	struct p9_qid qid;
413 	u32 st_mode;
414 	kuid_t st_uid;
415 	kgid_t st_gid;
416 	u64 st_nlink;
417 	u64 st_rdev;
418 	u64 st_size;
419 	u64 st_blksize;
420 	u64 st_blocks;
421 	u64 st_atime_sec;
422 	u64 st_atime_nsec;
423 	u64 st_mtime_sec;
424 	u64 st_mtime_nsec;
425 	u64 st_ctime_sec;
426 	u64 st_ctime_nsec;
427 	u64 st_btime_sec;
428 	u64 st_btime_nsec;
429 	u64 st_gen;
430 	u64 st_data_version;
431 };
432 
433 #define P9_STATS_MODE		0x00000001ULL
434 #define P9_STATS_NLINK		0x00000002ULL
435 #define P9_STATS_UID		0x00000004ULL
436 #define P9_STATS_GID		0x00000008ULL
437 #define P9_STATS_RDEV		0x00000010ULL
438 #define P9_STATS_ATIME		0x00000020ULL
439 #define P9_STATS_MTIME		0x00000040ULL
440 #define P9_STATS_CTIME		0x00000080ULL
441 #define P9_STATS_INO		0x00000100ULL
442 #define P9_STATS_SIZE		0x00000200ULL
443 #define P9_STATS_BLOCKS		0x00000400ULL
444 
445 #define P9_STATS_BTIME		0x00000800ULL
446 #define P9_STATS_GEN		0x00001000ULL
447 #define P9_STATS_DATA_VERSION	0x00002000ULL
448 
449 #define P9_STATS_BASIC		0x000007ffULL /* Mask for fields up to BLOCKS */
450 #define P9_STATS_ALL		0x00003fffULL /* Mask for All fields above */
451 
452 /**
453  * struct p9_iattr_dotl - P9 inode attribute for setattr
454  * @valid: bitfield specifying which fields are valid
455  *         same as in struct iattr
456  * @mode: File permission bits
457  * @uid: user id of owner
458  * @gid: group id
459  * @size: File size
460  * @atime_sec: Last access time, seconds
461  * @atime_nsec: Last access time, nanoseconds
462  * @mtime_sec: Last modification time, seconds
463  * @mtime_nsec: Last modification time, nanoseconds
464  */
465 
466 struct p9_iattr_dotl {
467 	u32 valid;
468 	u32 mode;
469 	kuid_t uid;
470 	kgid_t gid;
471 	u64 size;
472 	u64 atime_sec;
473 	u64 atime_nsec;
474 	u64 mtime_sec;
475 	u64 mtime_nsec;
476 };
477 
478 #define P9_LOCK_SUCCESS 0
479 #define P9_LOCK_BLOCKED 1
480 #define P9_LOCK_ERROR 2
481 #define P9_LOCK_GRACE 3
482 
483 #define P9_LOCK_FLAGS_BLOCK 1
484 #define P9_LOCK_FLAGS_RECLAIM 2
485 
486 /* struct p9_flock: POSIX lock structure
487  * @type - type of lock
488  * @flags - lock flags
489  * @start - starting offset of the lock
490  * @length - number of bytes
491  * @proc_id - process id which wants to take lock
492  * @client_id - client id
493  */
494 
495 struct p9_flock {
496 	u8 type;
497 	u32 flags;
498 	u64 start;
499 	u64 length;
500 	u32 proc_id;
501 	char *client_id;
502 };
503 
504 /* struct p9_getlock: getlock structure
505  * @type - type of lock
506  * @start - starting offset of the lock
507  * @length - number of bytes
508  * @proc_id - process id which wants to take lock
509  * @client_id - client id
510  */
511 
512 struct p9_getlock {
513 	u8 type;
514 	u64 start;
515 	u64 length;
516 	u32 proc_id;
517 	char *client_id;
518 };
519 
520 struct p9_rstatfs {
521 	u32 type;
522 	u32 bsize;
523 	u64 blocks;
524 	u64 bfree;
525 	u64 bavail;
526 	u64 files;
527 	u64 ffree;
528 	u64 fsid;
529 	u32 namelen;
530 };
531 
532 /**
533  * struct p9_fcall - primary packet structure
534  * @size: prefixed length of the structure
535  * @id: protocol operating identifier of type &p9_msg_t
536  * @tag: transaction id of the request
537  * @offset: used by marshalling routines to track current position in buffer
538  * @capacity: used by marshalling routines to track total malloc'd capacity
539  * @sdata: payload
540  * @zc: whether zero-copy is used
541  *
542  * &p9_fcall represents the structure for all 9P RPC
543  * transactions.  Requests are packaged into fcalls, and reponses
544  * must be extracted from them.
545  *
546  * See Also: http://plan9.bell-labs.com/magic/man2html/2/fcall
547  */
548 
549 struct p9_fcall {
550 	u32 size;
551 	u8 id;
552 	u16 tag;
553 
554 	size_t offset;
555 	size_t capacity;
556 
557 	struct kmem_cache *cache;
558 	u8 *sdata;
559 	bool zc;
560 };
561 
562 int p9_errstr2errno(char *errstr, int len);
563 
564 int p9_error_init(void);
565 #endif /* NET_9P_H */
566