xref: /linux/include/net/9p/9p.h (revision 9d9659b6c0ebf7dde65ebada4c67980818245913)
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  * @P9_DEBUG_PKT: packet marshalling/unmarshalling
42  * @P9_DEBUG_FSC: FS-cache tracing
43  *
44  * These flags are passed at mount time to turn on various levels of
45  * verbosity and tracing which will be output to the system logs.
46  */
47 
48 enum p9_debug_flags {
49 	P9_DEBUG_ERROR = 	(1<<0),
50 	P9_DEBUG_9P = 		(1<<2),
51 	P9_DEBUG_VFS =		(1<<3),
52 	P9_DEBUG_CONV =		(1<<4),
53 	P9_DEBUG_MUX =		(1<<5),
54 	P9_DEBUG_TRANS =	(1<<6),
55 	P9_DEBUG_SLABS =      	(1<<7),
56 	P9_DEBUG_FCALL =	(1<<8),
57 	P9_DEBUG_FID =		(1<<9),
58 	P9_DEBUG_PKT =		(1<<10),
59 	P9_DEBUG_FSC =		(1<<11),
60 };
61 
62 #ifdef CONFIG_NET_9P_DEBUG
63 extern unsigned int p9_debug_level;
64 
65 #define P9_DPRINTK(level, format, arg...) \
66 do {  \
67 	if ((p9_debug_level & level) == level) {\
68 		if (level == P9_DEBUG_9P) \
69 			printk(KERN_NOTICE "(%8.8d) " \
70 			format , task_pid_nr(current) , ## arg); \
71 		else \
72 			printk(KERN_NOTICE "-- %s (%d): " \
73 			format , __func__, task_pid_nr(current) , ## arg); \
74 	} \
75 } while (0)
76 
77 #else
78 #define P9_DPRINTK(level, format, arg...)  do { } while (0)
79 #endif
80 
81 #define P9_EPRINTK(level, format, arg...) \
82 do { \
83 	printk(level "9p: %s (%d): " \
84 		format , __func__, task_pid_nr(current), ## arg); \
85 } while (0)
86 
87 /**
88  * enum p9_msg_t - 9P message types
89  * @P9_TLERROR: not used
90  * @P9_RLERROR: response for any failed request for 9P2000.L
91  * @P9_TSTATFS: file system status request
92  * @P9_RSTATFS: file system status response
93  * @P9_TSYMLINK: make symlink request
94  * @P9_RSYMLINK: make symlink response
95  * @P9_TMKNOD: create a special file object request
96  * @P9_RMKNOD: create a special file object response
97  * @P9_TLCREATE: prepare a handle for I/O on an new file for 9P2000.L
98  * @P9_RLCREATE: response with file access information for 9P2000.L
99  * @P9_TRENAME: rename request
100  * @P9_RRENAME: rename response
101  * @P9_TMKDIR: create a directory request
102  * @P9_RMKDIR: create a directory response
103  * @P9_TVERSION: version handshake request
104  * @P9_RVERSION: version handshake response
105  * @P9_TAUTH: request to establish authentication channel
106  * @P9_RAUTH: response with authentication information
107  * @P9_TATTACH: establish user access to file service
108  * @P9_RATTACH: response with top level handle to file hierarchy
109  * @P9_TERROR: not used
110  * @P9_RERROR: response for any failed request
111  * @P9_TFLUSH: request to abort a previous request
112  * @P9_RFLUSH: response when previous request has been cancelled
113  * @P9_TWALK: descend a directory hierarchy
114  * @P9_RWALK: response with new handle for position within hierarchy
115  * @P9_TOPEN: prepare a handle for I/O on an existing file
116  * @P9_ROPEN: response with file access information
117  * @P9_TCREATE: prepare a handle for I/O on a new file
118  * @P9_RCREATE: response with file access information
119  * @P9_TREAD: request to transfer data from a file or directory
120  * @P9_RREAD: response with data requested
121  * @P9_TWRITE: reuqest to transfer data to a file
122  * @P9_RWRITE: response with out much data was transfered to file
123  * @P9_TCLUNK: forget about a handle to an entity within the file system
124  * @P9_RCLUNK: response when server has forgotten about the handle
125  * @P9_TREMOVE: request to remove an entity from the hierarchy
126  * @P9_RREMOVE: response when server has removed the entity
127  * @P9_TSTAT: request file entity attributes
128  * @P9_RSTAT: response with file entity attributes
129  * @P9_TWSTAT: request to update file entity attributes
130  * @P9_RWSTAT: response when file entity attributes are updated
131  *
132  * There are 14 basic operations in 9P2000, paired as
133  * requests and responses.  The one special case is ERROR
134  * as there is no @P9_TERROR request for clients to transmit to
135  * the server, but the server may respond to any other request
136  * with an @P9_RERROR.
137  *
138  * See Also: http://plan9.bell-labs.com/sys/man/5/INDEX.html
139  */
140 
141 enum p9_msg_t {
142 	P9_TSYNCFS = 0,
143 	P9_RSYNCFS,
144 	P9_TLERROR = 6,
145 	P9_RLERROR,
146 	P9_TSTATFS = 8,
147 	P9_RSTATFS,
148 	P9_TLOPEN = 12,
149 	P9_RLOPEN,
150 	P9_TLCREATE = 14,
151 	P9_RLCREATE,
152 	P9_TSYMLINK = 16,
153 	P9_RSYMLINK,
154 	P9_TMKNOD = 18,
155 	P9_RMKNOD,
156 	P9_TRENAME = 20,
157 	P9_RRENAME,
158 	P9_TREADLINK = 22,
159 	P9_RREADLINK,
160 	P9_TGETATTR = 24,
161 	P9_RGETATTR,
162 	P9_TSETATTR = 26,
163 	P9_RSETATTR,
164 	P9_TXATTRWALK = 30,
165 	P9_RXATTRWALK,
166 	P9_TXATTRCREATE = 32,
167 	P9_RXATTRCREATE,
168 	P9_TREADDIR = 40,
169 	P9_RREADDIR,
170 	P9_TFSYNC = 50,
171 	P9_RFSYNC,
172 	P9_TLOCK = 52,
173 	P9_RLOCK,
174 	P9_TGETLOCK = 54,
175 	P9_RGETLOCK,
176 	P9_TLINK = 70,
177 	P9_RLINK,
178 	P9_TMKDIR = 72,
179 	P9_RMKDIR,
180 	P9_TVERSION = 100,
181 	P9_RVERSION,
182 	P9_TAUTH = 102,
183 	P9_RAUTH,
184 	P9_TATTACH = 104,
185 	P9_RATTACH,
186 	P9_TERROR = 106,
187 	P9_RERROR,
188 	P9_TFLUSH = 108,
189 	P9_RFLUSH,
190 	P9_TWALK = 110,
191 	P9_RWALK,
192 	P9_TOPEN = 112,
193 	P9_ROPEN,
194 	P9_TCREATE = 114,
195 	P9_RCREATE,
196 	P9_TREAD = 116,
197 	P9_RREAD,
198 	P9_TWRITE = 118,
199 	P9_RWRITE,
200 	P9_TCLUNK = 120,
201 	P9_RCLUNK,
202 	P9_TREMOVE = 122,
203 	P9_RREMOVE,
204 	P9_TSTAT = 124,
205 	P9_RSTAT,
206 	P9_TWSTAT = 126,
207 	P9_RWSTAT,
208 };
209 
210 /**
211  * enum p9_open_mode_t - 9P open modes
212  * @P9_OREAD: open file for reading only
213  * @P9_OWRITE: open file for writing only
214  * @P9_ORDWR: open file for reading or writing
215  * @P9_OEXEC: open file for execution
216  * @P9_OTRUNC: truncate file to zero-length before opening it
217  * @P9_OREXEC: close the file when an exec(2) system call is made
218  * @P9_ORCLOSE: remove the file when the file is closed
219  * @P9_OAPPEND: open the file and seek to the end
220  * @P9_OEXCL: only create a file, do not open it
221  *
222  * 9P open modes differ slightly from Posix standard modes.
223  * In particular, there are extra modes which specify different
224  * semantic behaviors than may be available on standard Posix
225  * systems.  For example, @P9_OREXEC and @P9_ORCLOSE are modes that
226  * most likely will not be issued from the Linux VFS client, but may
227  * be supported by servers.
228  *
229  * See Also: http://plan9.bell-labs.com/magic/man2html/2/open
230  */
231 
232 enum p9_open_mode_t {
233 	P9_OREAD = 0x00,
234 	P9_OWRITE = 0x01,
235 	P9_ORDWR = 0x02,
236 	P9_OEXEC = 0x03,
237 	P9_OTRUNC = 0x10,
238 	P9_OREXEC = 0x20,
239 	P9_ORCLOSE = 0x40,
240 	P9_OAPPEND = 0x80,
241 	P9_OEXCL = 0x1000,
242 };
243 
244 /**
245  * enum p9_perm_t - 9P permissions
246  * @P9_DMDIR: mode bite for directories
247  * @P9_DMAPPEND: mode bit for is append-only
248  * @P9_DMEXCL: mode bit for excluse use (only one open handle allowed)
249  * @P9_DMMOUNT: mode bite for mount points
250  * @P9_DMAUTH: mode bit for authentication file
251  * @P9_DMTMP: mode bit for non-backed-up files
252  * @P9_DMSYMLINK: mode bit for symbolic links (9P2000.u)
253  * @P9_DMLINK: mode bit for hard-link (9P2000.u)
254  * @P9_DMDEVICE: mode bit for device files (9P2000.u)
255  * @P9_DMNAMEDPIPE: mode bit for named pipe (9P2000.u)
256  * @P9_DMSOCKET: mode bit for socket (9P2000.u)
257  * @P9_DMSETUID: mode bit for setuid (9P2000.u)
258  * @P9_DMSETGID: mode bit for setgid (9P2000.u)
259  * @P9_DMSETVTX: mode bit for sticky bit (9P2000.u)
260  *
261  * 9P permissions differ slightly from Posix standard modes.
262  *
263  * See Also: http://plan9.bell-labs.com/magic/man2html/2/stat
264  */
265 enum p9_perm_t {
266 	P9_DMDIR = 0x80000000,
267 	P9_DMAPPEND = 0x40000000,
268 	P9_DMEXCL = 0x20000000,
269 	P9_DMMOUNT = 0x10000000,
270 	P9_DMAUTH = 0x08000000,
271 	P9_DMTMP = 0x04000000,
272 /* 9P2000.u extensions */
273 	P9_DMSYMLINK = 0x02000000,
274 	P9_DMLINK = 0x01000000,
275 	P9_DMDEVICE = 0x00800000,
276 	P9_DMNAMEDPIPE = 0x00200000,
277 	P9_DMSOCKET = 0x00100000,
278 	P9_DMSETUID = 0x00080000,
279 	P9_DMSETGID = 0x00040000,
280 	P9_DMSETVTX = 0x00010000,
281 };
282 
283 /**
284  * enum p9_qid_t - QID types
285  * @P9_QTDIR: directory
286  * @P9_QTAPPEND: append-only
287  * @P9_QTEXCL: excluse use (only one open handle allowed)
288  * @P9_QTMOUNT: mount points
289  * @P9_QTAUTH: authentication file
290  * @P9_QTTMP: non-backed-up files
291  * @P9_QTSYMLINK: symbolic links (9P2000.u)
292  * @P9_QTLINK: hard-link (9P2000.u)
293  * @P9_QTFILE: normal files
294  *
295  * QID types are a subset of permissions - they are primarily
296  * used to differentiate semantics for a file system entity via
297  * a jump-table.  Their value is also the most signifigant 16 bits
298  * of the permission_t
299  *
300  * See Also: http://plan9.bell-labs.com/magic/man2html/2/stat
301  */
302 enum p9_qid_t {
303 	P9_QTDIR = 0x80,
304 	P9_QTAPPEND = 0x40,
305 	P9_QTEXCL = 0x20,
306 	P9_QTMOUNT = 0x10,
307 	P9_QTAUTH = 0x08,
308 	P9_QTTMP = 0x04,
309 	P9_QTSYMLINK = 0x02,
310 	P9_QTLINK = 0x01,
311 	P9_QTFILE = 0x00,
312 };
313 
314 /* 9P Magic Numbers */
315 #define P9_NOTAG	(u16)(~0)
316 #define P9_NOFID	(u32)(~0)
317 #define P9_MAXWELEM	16
318 
319 /* ample room for Twrite/Rread header */
320 #define P9_IOHDRSZ	24
321 
322 /* Room for readdir header */
323 #define P9_READDIRHDRSZ	24
324 
325 /**
326  * struct p9_str - length prefixed string type
327  * @len: length of the string
328  * @str: the string
329  *
330  * The protocol uses length prefixed strings for all
331  * string data, so we replicate that for our internal
332  * string members.
333  */
334 
335 struct p9_str {
336 	u16 len;
337 	char *str;
338 };
339 
340 /**
341  * struct p9_qid - file system entity information
342  * @type: 8-bit type &p9_qid_t
343  * @version: 16-bit monotonically incrementing version number
344  * @path: 64-bit per-server-unique ID for a file system element
345  *
346  * qids are identifiers used by 9P servers to track file system
347  * entities.  The type is used to differentiate semantics for operations
348  * on the entity (ie. read means something different on a directory than
349  * on a file).  The path provides a server unique index for an entity
350  * (roughly analogous to an inode number), while the version is updated
351  * every time a file is modified and can be used to maintain cache
352  * coherency between clients and serves.
353  * Servers will often differentiate purely synthetic entities by setting
354  * their version to 0, signaling that they should never be cached and
355  * should be accessed synchronously.
356  *
357  * See Also://plan9.bell-labs.com/magic/man2html/2/stat
358  */
359 
360 struct p9_qid {
361 	u8 type;
362 	u32 version;
363 	u64 path;
364 };
365 
366 /**
367  * struct p9_stat - file system metadata information
368  * @size: length prefix for this stat structure instance
369  * @type: the type of the server (equivilent to a major number)
370  * @dev: the sub-type of the server (equivilent to a minor number)
371  * @qid: unique id from the server of type &p9_qid
372  * @mode: Plan 9 format permissions of type &p9_perm_t
373  * @atime: Last access/read time
374  * @mtime: Last modify/write time
375  * @length: file length
376  * @name: last element of path (aka filename) in type &p9_str
377  * @uid: owner name in type &p9_str
378  * @gid: group owner in type &p9_str
379  * @muid: last modifier in type &p9_str
380  * @extension: area used to encode extended UNIX support in type &p9_str
381  * @n_uid: numeric user id of owner (part of 9p2000.u extension)
382  * @n_gid: numeric group id (part of 9p2000.u extension)
383  * @n_muid: numeric user id of laster modifier (part of 9p2000.u extension)
384  *
385  * See Also: http://plan9.bell-labs.com/magic/man2html/2/stat
386  */
387 
388 struct p9_wstat {
389 	u16 size;
390 	u16 type;
391 	u32 dev;
392 	struct p9_qid qid;
393 	u32 mode;
394 	u32 atime;
395 	u32 mtime;
396 	u64 length;
397 	char *name;
398 	char *uid;
399 	char *gid;
400 	char *muid;
401 	char *extension;	/* 9p2000.u extensions */
402 	u32 n_uid;		/* 9p2000.u extensions */
403 	u32 n_gid;		/* 9p2000.u extensions */
404 	u32 n_muid;		/* 9p2000.u extensions */
405 };
406 
407 struct p9_stat_dotl {
408 	u64 st_result_mask;
409 	struct p9_qid qid;
410 	u32 st_mode;
411 	u32 st_uid;
412 	u32 st_gid;
413 	u64 st_nlink;
414 	u64 st_rdev;
415 	u64 st_size;
416 	u64 st_blksize;
417 	u64 st_blocks;
418 	u64 st_atime_sec;
419 	u64 st_atime_nsec;
420 	u64 st_mtime_sec;
421 	u64 st_mtime_nsec;
422 	u64 st_ctime_sec;
423 	u64 st_ctime_nsec;
424 	u64 st_btime_sec;
425 	u64 st_btime_nsec;
426 	u64 st_gen;
427 	u64 st_data_version;
428 };
429 
430 #define P9_STATS_MODE		0x00000001ULL
431 #define P9_STATS_NLINK		0x00000002ULL
432 #define P9_STATS_UID		0x00000004ULL
433 #define P9_STATS_GID		0x00000008ULL
434 #define P9_STATS_RDEV		0x00000010ULL
435 #define P9_STATS_ATIME		0x00000020ULL
436 #define P9_STATS_MTIME		0x00000040ULL
437 #define P9_STATS_CTIME		0x00000080ULL
438 #define P9_STATS_INO		0x00000100ULL
439 #define P9_STATS_SIZE		0x00000200ULL
440 #define P9_STATS_BLOCKS		0x00000400ULL
441 
442 #define P9_STATS_BTIME		0x00000800ULL
443 #define P9_STATS_GEN		0x00001000ULL
444 #define P9_STATS_DATA_VERSION	0x00002000ULL
445 
446 #define P9_STATS_BASIC		0x000007ffULL /* Mask for fields up to BLOCKS */
447 #define P9_STATS_ALL		0x00003fffULL /* Mask for All fields above */
448 
449 /**
450  * struct p9_iattr_dotl - P9 inode attribute for setattr
451  * @valid: bitfield specifying which fields are valid
452  *         same as in struct iattr
453  * @mode: File permission bits
454  * @uid: user id of owner
455  * @gid: group id
456  * @size: File size
457  * @atime_sec: Last access time, seconds
458  * @atime_nsec: Last access time, nanoseconds
459  * @mtime_sec: Last modification time, seconds
460  * @mtime_nsec: Last modification time, nanoseconds
461  */
462 
463 struct p9_iattr_dotl {
464 	u32 valid;
465 	u32 mode;
466 	u32 uid;
467 	u32 gid;
468 	u64 size;
469 	u64 atime_sec;
470 	u64 atime_nsec;
471 	u64 mtime_sec;
472 	u64 mtime_nsec;
473 };
474 
475 #define P9_LOCK_SUCCESS 0
476 #define P9_LOCK_BLOCKED 1
477 #define P9_LOCK_ERROR 2
478 #define P9_LOCK_GRACE 3
479 
480 #define P9_LOCK_FLAGS_BLOCK 1
481 #define P9_LOCK_FLAGS_RECLAIM 2
482 
483 /* struct p9_flock: POSIX lock structure
484  * @type - type of lock
485  * @flags - lock flags
486  * @start - starting offset of the lock
487  * @length - number of bytes
488  * @proc_id - process id which wants to take lock
489  * @client_id - client id
490  */
491 
492 struct p9_flock {
493 	u8 type;
494 	u32 flags;
495 	u64 start;
496 	u64 length;
497 	u32 proc_id;
498 	char *client_id;
499 };
500 
501 /* struct p9_getlock: getlock structure
502  * @type - type of lock
503  * @start - starting offset of the lock
504  * @length - number of bytes
505  * @proc_id - process id which wants to take lock
506  * @client_id - client id
507  */
508 
509 struct p9_getlock {
510 	u8 type;
511 	u64 start;
512 	u64 length;
513 	u32 proc_id;
514 	char *client_id;
515 };
516 
517 /* Structures for Protocol Operations */
518 struct p9_tstatfs {
519 	u32 fid;
520 };
521 
522 struct p9_rstatfs {
523 	u32 type;
524 	u32 bsize;
525 	u64 blocks;
526 	u64 bfree;
527 	u64 bavail;
528 	u64 files;
529 	u64 ffree;
530 	u64 fsid;
531 	u32 namelen;
532 };
533 
534 struct p9_trename {
535 	u32 fid;
536 	u32 newdirfid;
537 	struct p9_str name;
538 };
539 
540 struct p9_rrename {
541 };
542 
543 struct p9_tversion {
544 	u32 msize;
545 	struct p9_str version;
546 };
547 
548 struct p9_rversion {
549 	u32 msize;
550 	struct p9_str version;
551 };
552 
553 struct p9_tauth {
554 	u32 afid;
555 	struct p9_str uname;
556 	struct p9_str aname;
557 	u32 n_uname;		/* 9P2000.u extensions */
558 };
559 
560 struct p9_rauth {
561 	struct p9_qid qid;
562 };
563 
564 struct p9_rerror {
565 	struct p9_str error;
566 	u32 errno;		/* 9p2000.u extension */
567 };
568 
569 struct p9_tflush {
570 	u16 oldtag;
571 };
572 
573 struct p9_rflush {
574 };
575 
576 struct p9_tattach {
577 	u32 fid;
578 	u32 afid;
579 	struct p9_str uname;
580 	struct p9_str aname;
581 	u32 n_uname;		/* 9P2000.u extensions */
582 };
583 
584 struct p9_rattach {
585 	struct p9_qid qid;
586 };
587 
588 struct p9_twalk {
589 	u32 fid;
590 	u32 newfid;
591 	u16 nwname;
592 	struct p9_str wnames[16];
593 };
594 
595 struct p9_rwalk {
596 	u16 nwqid;
597 	struct p9_qid wqids[16];
598 };
599 
600 struct p9_topen {
601 	u32 fid;
602 	u8 mode;
603 };
604 
605 struct p9_ropen {
606 	struct p9_qid qid;
607 	u32 iounit;
608 };
609 
610 struct p9_tcreate {
611 	u32 fid;
612 	struct p9_str name;
613 	u32 perm;
614 	u8 mode;
615 	struct p9_str extension;
616 };
617 
618 struct p9_rcreate {
619 	struct p9_qid qid;
620 	u32 iounit;
621 };
622 
623 struct p9_tread {
624 	u32 fid;
625 	u64 offset;
626 	u32 count;
627 };
628 
629 struct p9_rread {
630 	u32 count;
631 	u8 *data;
632 };
633 
634 struct p9_twrite {
635 	u32 fid;
636 	u64 offset;
637 	u32 count;
638 	u8 *data;
639 };
640 
641 struct p9_rwrite {
642 	u32 count;
643 };
644 
645 struct p9_treaddir {
646 	u32 fid;
647 	u64 offset;
648 	u32 count;
649 };
650 
651 struct p9_rreaddir {
652 	u32 count;
653 	u8 *data;
654 };
655 
656 
657 struct p9_tclunk {
658 	u32 fid;
659 };
660 
661 struct p9_rclunk {
662 };
663 
664 struct p9_tremove {
665 	u32 fid;
666 };
667 
668 struct p9_rremove {
669 };
670 
671 struct p9_tstat {
672 	u32 fid;
673 };
674 
675 struct p9_rstat {
676 	struct p9_wstat stat;
677 };
678 
679 struct p9_twstat {
680 	u32 fid;
681 	struct p9_wstat stat;
682 };
683 
684 struct p9_rwstat {
685 };
686 
687 /**
688  * struct p9_fcall - primary packet structure
689  * @size: prefixed length of the structure
690  * @id: protocol operating identifier of type &p9_msg_t
691  * @tag: transaction id of the request
692  * @offset: used by marshalling routines to track currentposition in buffer
693  * @capacity: used by marshalling routines to track total malloc'd capacity
694  * @pubuf: Payload user buffer given by the caller
695  * @pubuf: Payload kernel buffer given by the caller
696  * @pbuf_size: pubuf/pkbuf(only one will be !NULL) size to be read/write.
697  * @private: For transport layer's use.
698  * @sdata: payload
699  *
700  * &p9_fcall represents the structure for all 9P RPC
701  * transactions.  Requests are packaged into fcalls, and reponses
702  * must be extracted from them.
703  *
704  * See Also: http://plan9.bell-labs.com/magic/man2html/2/fcall
705  */
706 
707 struct p9_fcall {
708 	u32 size;
709 	u8 id;
710 	u16 tag;
711 
712 	size_t offset;
713 	size_t capacity;
714 	char __user *pubuf;
715 	char *pkbuf;
716 	size_t pbuf_size;
717 	void *private;
718 
719 	uint8_t *sdata;
720 };
721 
722 struct p9_idpool;
723 
724 int p9_errstr2errno(char *errstr, int len);
725 
726 struct p9_idpool *p9_idpool_create(void);
727 void p9_idpool_destroy(struct p9_idpool *);
728 int p9_idpool_get(struct p9_idpool *p);
729 void p9_idpool_put(int id, struct p9_idpool *p);
730 int p9_idpool_check(int id, struct p9_idpool *p);
731 
732 int p9_error_init(void);
733 int p9_errstr2errno(char *, int);
734 int p9_trans_fd_init(void);
735 void p9_trans_fd_exit(void);
736 #endif /* NET_9P_H */
737