xref: /openbmc/linux/include/net/9p/9p.h (revision b830f94f) 
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * include/net/9p/9p.h
4  *
5  * 9P protocol definitions.
6  *
7  *  Copyright (C) 2005 by Latchesar Ionkov <lucho@ionkov.net>
8  *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
9  *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
10  */
11 
12 #ifndef NET_9P_H
13 #define NET_9P_H
14 
15 /**
16  * enum p9_debug_flags - bits for mount time debug parameter
17  * @P9_DEBUG_ERROR: more verbose error messages including original error string
18  * @P9_DEBUG_9P: 9P protocol tracing
19  * @P9_DEBUG_VFS: VFS API tracing
20  * @P9_DEBUG_CONV: protocol conversion tracing
21  * @P9_DEBUG_MUX: trace management of concurrent transactions
22  * @P9_DEBUG_TRANS: transport tracing
23  * @P9_DEBUG_SLABS: memory management tracing
24  * @P9_DEBUG_FCALL: verbose dump of protocol messages
25  * @P9_DEBUG_FID: fid allocation/deallocation tracking
26  * @P9_DEBUG_PKT: packet marshalling/unmarshalling
27  * @P9_DEBUG_FSC: FS-cache tracing
28  * @P9_DEBUG_VPKT: Verbose packet debugging (full packet dump)
29  *
30  * These flags are passed at mount time to turn on various levels of
31  * verbosity and tracing which will be output to the system logs.
32  */
33 
34 enum p9_debug_flags {
35 	P9_DEBUG_ERROR = 	(1<<0),
36 	P9_DEBUG_9P = 		(1<<2),
37 	P9_DEBUG_VFS =		(1<<3),
38 	P9_DEBUG_CONV =		(1<<4),
39 	P9_DEBUG_MUX =		(1<<5),
40 	P9_DEBUG_TRANS =	(1<<6),
41 	P9_DEBUG_SLABS =      	(1<<7),
42 	P9_DEBUG_FCALL =	(1<<8),
43 	P9_DEBUG_FID =		(1<<9),
44 	P9_DEBUG_PKT =		(1<<10),
45 	P9_DEBUG_FSC =		(1<<11),
46 	P9_DEBUG_VPKT =		(1<<12),
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 };
219 
220 /**
221  * enum p9_perm_t - 9P permissions
222  * @P9_DMDIR: mode bit for directories
223  * @P9_DMAPPEND: mode bit for is append-only
224  * @P9_DMEXCL: mode bit for excluse use (only one open handle allowed)
225  * @P9_DMMOUNT: mode bit for mount points
226  * @P9_DMAUTH: mode bit for authentication file
227  * @P9_DMTMP: mode bit for non-backed-up files
228  * @P9_DMSYMLINK: mode bit for symbolic links (9P2000.u)
229  * @P9_DMLINK: mode bit for hard-link (9P2000.u)
230  * @P9_DMDEVICE: mode bit for device files (9P2000.u)
231  * @P9_DMNAMEDPIPE: mode bit for named pipe (9P2000.u)
232  * @P9_DMSOCKET: mode bit for socket (9P2000.u)
233  * @P9_DMSETUID: mode bit for setuid (9P2000.u)
234  * @P9_DMSETGID: mode bit for setgid (9P2000.u)
235  * @P9_DMSETVTX: mode bit for sticky bit (9P2000.u)
236  *
237  * 9P permissions differ slightly from Posix standard modes.
238  *
239  * See Also: http://plan9.bell-labs.com/magic/man2html/2/stat
240  */
241 enum p9_perm_t {
242 	P9_DMDIR = 0x80000000,
243 	P9_DMAPPEND = 0x40000000,
244 	P9_DMEXCL = 0x20000000,
245 	P9_DMMOUNT = 0x10000000,
246 	P9_DMAUTH = 0x08000000,
247 	P9_DMTMP = 0x04000000,
248 /* 9P2000.u extensions */
249 	P9_DMSYMLINK = 0x02000000,
250 	P9_DMLINK = 0x01000000,
251 	P9_DMDEVICE = 0x00800000,
252 	P9_DMNAMEDPIPE = 0x00200000,
253 	P9_DMSOCKET = 0x00100000,
254 	P9_DMSETUID = 0x00080000,
255 	P9_DMSETGID = 0x00040000,
256 	P9_DMSETVTX = 0x00010000,
257 };
258 
259 /* 9p2000.L open flags */
260 #define P9_DOTL_RDONLY        00000000
261 #define P9_DOTL_WRONLY        00000001
262 #define P9_DOTL_RDWR          00000002
263 #define P9_DOTL_NOACCESS      00000003
264 #define P9_DOTL_CREATE        00000100
265 #define P9_DOTL_EXCL          00000200
266 #define P9_DOTL_NOCTTY        00000400
267 #define P9_DOTL_TRUNC         00001000
268 #define P9_DOTL_APPEND        00002000
269 #define P9_DOTL_NONBLOCK      00004000
270 #define P9_DOTL_DSYNC         00010000
271 #define P9_DOTL_FASYNC        00020000
272 #define P9_DOTL_DIRECT        00040000
273 #define P9_DOTL_LARGEFILE     00100000
274 #define P9_DOTL_DIRECTORY     00200000
275 #define P9_DOTL_NOFOLLOW      00400000
276 #define P9_DOTL_NOATIME       01000000
277 #define P9_DOTL_CLOEXEC       02000000
278 #define P9_DOTL_SYNC          04000000
279 
280 /* 9p2000.L at flags */
281 #define P9_DOTL_AT_REMOVEDIR		0x200
282 
283 /* 9p2000.L lock type */
284 #define P9_LOCK_TYPE_RDLCK 0
285 #define P9_LOCK_TYPE_WRLCK 1
286 #define P9_LOCK_TYPE_UNLCK 2
287 
288 /**
289  * enum p9_qid_t - QID types
290  * @P9_QTDIR: directory
291  * @P9_QTAPPEND: append-only
292  * @P9_QTEXCL: excluse use (only one open handle allowed)
293  * @P9_QTMOUNT: mount points
294  * @P9_QTAUTH: authentication file
295  * @P9_QTTMP: non-backed-up files
296  * @P9_QTSYMLINK: symbolic links (9P2000.u)
297  * @P9_QTLINK: hard-link (9P2000.u)
298  * @P9_QTFILE: normal files
299  *
300  * QID types are a subset of permissions - they are primarily
301  * used to differentiate semantics for a file system entity via
302  * a jump-table.  Their value is also the most significant 16 bits
303  * of the permission_t
304  *
305  * See Also: http://plan9.bell-labs.com/magic/man2html/2/stat
306  */
307 enum p9_qid_t {
308 	P9_QTDIR = 0x80,
309 	P9_QTAPPEND = 0x40,
310 	P9_QTEXCL = 0x20,
311 	P9_QTMOUNT = 0x10,
312 	P9_QTAUTH = 0x08,
313 	P9_QTTMP = 0x04,
314 	P9_QTSYMLINK = 0x02,
315 	P9_QTLINK = 0x01,
316 	P9_QTFILE = 0x00,
317 };
318 
319 /* 9P Magic Numbers */
320 #define P9_NOTAG	(u16)(~0)
321 #define P9_NOFID	(u32)(~0)
322 #define P9_MAXWELEM	16
323 
324 /* Minimal header size: size[4] type[1] tag[2] */
325 #define P9_HDRSZ	7
326 
327 /* ample room for Twrite/Rread header */
328 #define P9_IOHDRSZ	24
329 
330 /* Room for readdir header */
331 #define P9_READDIRHDRSZ	24
332 
333 /* size of header for zero copy read/write */
334 #define P9_ZC_HDR_SZ 4096
335 
336 /**
337  * struct p9_qid - file system entity information
338  * @type: 8-bit type &p9_qid_t
339  * @version: 16-bit monotonically incrementing version number
340  * @path: 64-bit per-server-unique ID for a file system element
341  *
342  * qids are identifiers used by 9P servers to track file system
343  * entities.  The type is used to differentiate semantics for operations
344  * on the entity (ie. read means something different on a directory than
345  * on a file).  The path provides a server unique index for an entity
346  * (roughly analogous to an inode number), while the version is updated
347  * every time a file is modified and can be used to maintain cache
348  * coherency between clients and serves.
349  * Servers will often differentiate purely synthetic entities by setting
350  * their version to 0, signaling that they should never be cached and
351  * should be accessed synchronously.
352  *
353  * See Also://plan9.bell-labs.com/magic/man2html/2/stat
354  */
355 
356 struct p9_qid {
357 	u8 type;
358 	u32 version;
359 	u64 path;
360 };
361 
362 /**
363  * struct p9_wstat - file system metadata information
364  * @size: length prefix for this stat structure instance
365  * @type: the type of the server (equivalent to a major number)
366  * @dev: the sub-type of the server (equivalent to a minor number)
367  * @qid: unique id from the server of type &p9_qid
368  * @mode: Plan 9 format permissions of type &p9_perm_t
369  * @atime: Last access/read time
370  * @mtime: Last modify/write time
371  * @length: file length
372  * @name: last element of path (aka filename)
373  * @uid: owner name
374  * @gid: group owner
375  * @muid: last modifier
376  * @extension: area used to encode extended UNIX support
377  * @n_uid: numeric user id of owner (part of 9p2000.u extension)
378  * @n_gid: numeric group id (part of 9p2000.u extension)
379  * @n_muid: numeric user id of laster modifier (part of 9p2000.u extension)
380  *
381  * See Also: http://plan9.bell-labs.com/magic/man2html/2/stat
382  */
383 
384 struct p9_wstat {
385 	u16 size;
386 	u16 type;
387 	u32 dev;
388 	struct p9_qid qid;
389 	u32 mode;
390 	u32 atime;
391 	u32 mtime;
392 	u64 length;
393 	const char *name;
394 	const char *uid;
395 	const char *gid;
396 	const char *muid;
397 	char *extension;	/* 9p2000.u extensions */
398 	kuid_t n_uid;		/* 9p2000.u extensions */
399 	kgid_t n_gid;		/* 9p2000.u extensions */
400 	kuid_t n_muid;		/* 9p2000.u extensions */
401 };
402 
403 struct p9_stat_dotl {
404 	u64 st_result_mask;
405 	struct p9_qid qid;
406 	u32 st_mode;
407 	kuid_t st_uid;
408 	kgid_t st_gid;
409 	u64 st_nlink;
410 	u64 st_rdev;
411 	u64 st_size;
412 	u64 st_blksize;
413 	u64 st_blocks;
414 	u64 st_atime_sec;
415 	u64 st_atime_nsec;
416 	u64 st_mtime_sec;
417 	u64 st_mtime_nsec;
418 	u64 st_ctime_sec;
419 	u64 st_ctime_nsec;
420 	u64 st_btime_sec;
421 	u64 st_btime_nsec;
422 	u64 st_gen;
423 	u64 st_data_version;
424 };
425 
426 #define P9_STATS_MODE		0x00000001ULL
427 #define P9_STATS_NLINK		0x00000002ULL
428 #define P9_STATS_UID		0x00000004ULL
429 #define P9_STATS_GID		0x00000008ULL
430 #define P9_STATS_RDEV		0x00000010ULL
431 #define P9_STATS_ATIME		0x00000020ULL
432 #define P9_STATS_MTIME		0x00000040ULL
433 #define P9_STATS_CTIME		0x00000080ULL
434 #define P9_STATS_INO		0x00000100ULL
435 #define P9_STATS_SIZE		0x00000200ULL
436 #define P9_STATS_BLOCKS		0x00000400ULL
437 
438 #define P9_STATS_BTIME		0x00000800ULL
439 #define P9_STATS_GEN		0x00001000ULL
440 #define P9_STATS_DATA_VERSION	0x00002000ULL
441 
442 #define P9_STATS_BASIC		0x000007ffULL /* Mask for fields up to BLOCKS */
443 #define P9_STATS_ALL		0x00003fffULL /* Mask for All fields above */
444 
445 /**
446  * struct p9_iattr_dotl - P9 inode attribute for setattr
447  * @valid: bitfield specifying which fields are valid
448  *         same as in struct iattr
449  * @mode: File permission bits
450  * @uid: user id of owner
451  * @gid: group id
452  * @size: File size
453  * @atime_sec: Last access time, seconds
454  * @atime_nsec: Last access time, nanoseconds
455  * @mtime_sec: Last modification time, seconds
456  * @mtime_nsec: Last modification time, nanoseconds
457  */
458 
459 struct p9_iattr_dotl {
460 	u32 valid;
461 	u32 mode;
462 	kuid_t uid;
463 	kgid_t gid;
464 	u64 size;
465 	u64 atime_sec;
466 	u64 atime_nsec;
467 	u64 mtime_sec;
468 	u64 mtime_nsec;
469 };
470 
471 #define P9_LOCK_SUCCESS 0
472 #define P9_LOCK_BLOCKED 1
473 #define P9_LOCK_ERROR 2
474 #define P9_LOCK_GRACE 3
475 
476 #define P9_LOCK_FLAGS_BLOCK 1
477 #define P9_LOCK_FLAGS_RECLAIM 2
478 
479 /* struct p9_flock: POSIX lock structure
480  * @type - type of lock
481  * @flags - lock flags
482  * @start - starting offset of the lock
483  * @length - number of bytes
484  * @proc_id - process id which wants to take lock
485  * @client_id - client id
486  */
487 
488 struct p9_flock {
489 	u8 type;
490 	u32 flags;
491 	u64 start;
492 	u64 length;
493 	u32 proc_id;
494 	char *client_id;
495 };
496 
497 /* struct p9_getlock: getlock structure
498  * @type - type of lock
499  * @start - starting offset of the lock
500  * @length - number of bytes
501  * @proc_id - process id which wants to take lock
502  * @client_id - client id
503  */
504 
505 struct p9_getlock {
506 	u8 type;
507 	u64 start;
508 	u64 length;
509 	u32 proc_id;
510 	char *client_id;
511 };
512 
513 struct p9_rstatfs {
514 	u32 type;
515 	u32 bsize;
516 	u64 blocks;
517 	u64 bfree;
518 	u64 bavail;
519 	u64 files;
520 	u64 ffree;
521 	u64 fsid;
522 	u32 namelen;
523 };
524 
525 /**
526  * struct p9_fcall - primary packet structure
527  * @size: prefixed length of the structure
528  * @id: protocol operating identifier of type &p9_msg_t
529  * @tag: transaction id of the request
530  * @offset: used by marshalling routines to track current position in buffer
531  * @capacity: used by marshalling routines to track total malloc'd capacity
532  * @sdata: payload
533  *
534  * &p9_fcall represents the structure for all 9P RPC
535  * transactions.  Requests are packaged into fcalls, and reponses
536  * must be extracted from them.
537  *
538  * See Also: http://plan9.bell-labs.com/magic/man2html/2/fcall
539  */
540 
541 struct p9_fcall {
542 	u32 size;
543 	u8 id;
544 	u16 tag;
545 
546 	size_t offset;
547 	size_t capacity;
548 
549 	struct kmem_cache *cache;
550 	u8 *sdata;
551 };
552 
553 int p9_errstr2errno(char *errstr, int len);
554 
555 int p9_error_init(void);
556 int p9_trans_fd_init(void);
557 void p9_trans_fd_exit(void);
558 #endif /* NET_9P_H */
559