tests/tcg: Do not require FE_* exception bits
[qemu.git] / hw / 9pfs / 9p.h
1 #ifndef QEMU_9P_H
2 #define QEMU_9P_H
3
4 #include <dirent.h>
5 #include <utime.h>
6 #include <sys/resource.h>
7 #include "fsdev/file-op-9p.h"
8 #include "fsdev/9p-iov-marshal.h"
9 #include "qemu/thread.h"
10 #include "qemu/coroutine.h"
11 #include "qemu/qht.h"
12
13 enum {
14 P9_TLERROR = 6,
15 P9_RLERROR,
16 P9_TSTATFS = 8,
17 P9_RSTATFS,
18 P9_TLOPEN = 12,
19 P9_RLOPEN,
20 P9_TLCREATE = 14,
21 P9_RLCREATE,
22 P9_TSYMLINK = 16,
23 P9_RSYMLINK,
24 P9_TMKNOD = 18,
25 P9_RMKNOD,
26 P9_TRENAME = 20,
27 P9_RRENAME,
28 P9_TREADLINK = 22,
29 P9_RREADLINK,
30 P9_TGETATTR = 24,
31 P9_RGETATTR,
32 P9_TSETATTR = 26,
33 P9_RSETATTR,
34 P9_TXATTRWALK = 30,
35 P9_RXATTRWALK,
36 P9_TXATTRCREATE = 32,
37 P9_RXATTRCREATE,
38 P9_TREADDIR = 40,
39 P9_RREADDIR,
40 P9_TFSYNC = 50,
41 P9_RFSYNC,
42 P9_TLOCK = 52,
43 P9_RLOCK,
44 P9_TGETLOCK = 54,
45 P9_RGETLOCK,
46 P9_TLINK = 70,
47 P9_RLINK,
48 P9_TMKDIR = 72,
49 P9_RMKDIR,
50 P9_TRENAMEAT = 74,
51 P9_RRENAMEAT,
52 P9_TUNLINKAT = 76,
53 P9_RUNLINKAT,
54 P9_TVERSION = 100,
55 P9_RVERSION,
56 P9_TAUTH = 102,
57 P9_RAUTH,
58 P9_TATTACH = 104,
59 P9_RATTACH,
60 P9_TERROR = 106,
61 P9_RERROR,
62 P9_TFLUSH = 108,
63 P9_RFLUSH,
64 P9_TWALK = 110,
65 P9_RWALK,
66 P9_TOPEN = 112,
67 P9_ROPEN,
68 P9_TCREATE = 114,
69 P9_RCREATE,
70 P9_TREAD = 116,
71 P9_RREAD,
72 P9_TWRITE = 118,
73 P9_RWRITE,
74 P9_TCLUNK = 120,
75 P9_RCLUNK,
76 P9_TREMOVE = 122,
77 P9_RREMOVE,
78 P9_TSTAT = 124,
79 P9_RSTAT,
80 P9_TWSTAT = 126,
81 P9_RWSTAT,
82 };
83
84
85 /* qid.types */
86 enum {
87 P9_QTDIR = 0x80,
88 P9_QTAPPEND = 0x40,
89 P9_QTEXCL = 0x20,
90 P9_QTMOUNT = 0x10,
91 P9_QTAUTH = 0x08,
92 P9_QTTMP = 0x04,
93 P9_QTSYMLINK = 0x02,
94 P9_QTLINK = 0x01,
95 P9_QTFILE = 0x00,
96 };
97
98 typedef enum P9ProtoVersion {
99 V9FS_PROTO_2000U = 0x01,
100 V9FS_PROTO_2000L = 0x02,
101 } P9ProtoVersion;
102
103 /**
104 * @brief Minimum message size supported by this 9pfs server.
105 *
106 * A client establishes a session by sending a Tversion request along with a
107 * 'msize' parameter which suggests the server a maximum message size ever to be
108 * used for communication (for both requests and replies) between client and
109 * server during that session. If client suggests a 'msize' smaller than this
110 * value then session is denied by server with an error response.
111 */
112 #define P9_MIN_MSIZE 4096
113
114 #define P9_NOTAG UINT16_MAX
115 #define P9_NOFID UINT32_MAX
116 #define P9_MAXWELEM 16
117
118 #define FID_REFERENCED 0x1
119 #define FID_NON_RECLAIMABLE 0x2
120 static inline char *rpath(FsContext *ctx, const char *path)
121 {
122 return g_strdup_printf("%s/%s", ctx->fs_root, path);
123 }
124
125 /*
126 * ample room for Twrite/Rread header
127 * size[4] Tread/Twrite tag[2] fid[4] offset[8] count[4]
128 */
129 #define P9_IOHDRSZ 24
130
131 typedef struct V9fsPDU V9fsPDU;
132 typedef struct V9fsState V9fsState;
133 typedef struct V9fsTransport V9fsTransport;
134
135 typedef struct {
136 uint32_t size_le;
137 uint8_t id;
138 uint16_t tag_le;
139 } QEMU_PACKED P9MsgHeader;
140 /* According to the specification, 9p messages start with a 7-byte header.
141 * Since most of the code uses this header size in literal form, we must be
142 * sure this is indeed the case.
143 */
144 QEMU_BUILD_BUG_ON(sizeof(P9MsgHeader) != 7);
145
146 struct V9fsPDU
147 {
148 uint32_t size;
149 uint16_t tag;
150 uint8_t id;
151 uint8_t cancelled;
152 CoQueue complete;
153 V9fsState *s;
154 QLIST_ENTRY(V9fsPDU) next;
155 uint32_t idx;
156 };
157
158
159 /* FIXME
160 * 1) change user needs to set groups and stuff
161 */
162
163 #define MAX_REQ 128
164 #define MAX_TAG_LEN 32
165
166 #define BUG_ON(cond) assert(!(cond))
167
168 typedef struct V9fsFidState V9fsFidState;
169
170 enum {
171 P9_FID_NONE = 0,
172 P9_FID_FILE,
173 P9_FID_DIR,
174 P9_FID_XATTR,
175 };
176
177 typedef struct V9fsConf
178 {
179 /* tag name for the device */
180 char *tag;
181 char *fsdev_id;
182 } V9fsConf;
183
184 /* 9p2000.L xattr flags (matches Linux values) */
185 #define P9_XATTR_CREATE 1
186 #define P9_XATTR_REPLACE 2
187
188 typedef struct V9fsXattr
189 {
190 uint64_t copied_len;
191 uint64_t len;
192 void *value;
193 V9fsString name;
194 int flags;
195 bool xattrwalk_fid;
196 } V9fsXattr;
197
198 typedef struct V9fsDir {
199 DIR *stream;
200 P9ProtoVersion proto_version;
201 /* readdir mutex type used for 9P2000.u protocol variant */
202 CoMutex readdir_mutex_u;
203 /* readdir mutex type used for 9P2000.L protocol variant */
204 QemuMutex readdir_mutex_L;
205 } V9fsDir;
206
207 static inline void v9fs_readdir_lock(V9fsDir *dir)
208 {
209 if (dir->proto_version == V9FS_PROTO_2000U) {
210 qemu_co_mutex_lock(&dir->readdir_mutex_u);
211 } else {
212 qemu_mutex_lock(&dir->readdir_mutex_L);
213 }
214 }
215
216 static inline void v9fs_readdir_unlock(V9fsDir *dir)
217 {
218 if (dir->proto_version == V9FS_PROTO_2000U) {
219 qemu_co_mutex_unlock(&dir->readdir_mutex_u);
220 } else {
221 qemu_mutex_unlock(&dir->readdir_mutex_L);
222 }
223 }
224
225 static inline void v9fs_readdir_init(P9ProtoVersion proto_version, V9fsDir *dir)
226 {
227 dir->proto_version = proto_version;
228 if (proto_version == V9FS_PROTO_2000U) {
229 qemu_co_mutex_init(&dir->readdir_mutex_u);
230 } else {
231 qemu_mutex_init(&dir->readdir_mutex_L);
232 }
233 }
234
235 /**
236 * Type for 9p fs drivers' (a.k.a. 9p backends) result of readdir requests,
237 * which is a chained list of directory entries.
238 */
239 typedef struct V9fsDirEnt {
240 /* mandatory (must not be NULL) information for all readdir requests */
241 struct dirent *dent;
242 /*
243 * optional (may be NULL): A full stat of each directory entry is just
244 * done if explicitly told to fs driver.
245 */
246 struct stat *st;
247 /*
248 * instead of an array, directory entries are always returned as
249 * chained list, that's because the amount of entries retrieved by fs
250 * drivers is dependent on the individual entries' name (since response
251 * messages are size limited), so the final amount cannot be estimated
252 * before hand
253 */
254 struct V9fsDirEnt *next;
255 } V9fsDirEnt;
256
257 /*
258 * Filled by fs driver on open and other
259 * calls.
260 */
261 union V9fsFidOpenState {
262 int fd;
263 V9fsDir dir;
264 V9fsXattr xattr;
265 /*
266 * private pointer for fs drivers, that
267 * have its own internal representation of
268 * open files.
269 */
270 void *private;
271 };
272
273 struct V9fsFidState
274 {
275 int fid_type;
276 int32_t fid;
277 V9fsPath path;
278 V9fsFidOpenState fs;
279 V9fsFidOpenState fs_reclaim;
280 int flags;
281 int open_flags;
282 uid_t uid;
283 int ref;
284 int clunked;
285 V9fsFidState *next;
286 V9fsFidState *rclm_lst;
287 };
288
289 typedef enum AffixType_t {
290 AffixType_Prefix,
291 AffixType_Suffix, /* A.k.a. postfix. */
292 } AffixType_t;
293
294 /**
295 * @brief Unique affix of variable length.
296 *
297 * An affix is (currently) either a suffix or a prefix, which is either
298 * going to be prepended (prefix) or appended (suffix) with some other
299 * number for the goal to generate unique numbers. Accordingly the
300 * suffixes (or prefixes) we generate @b must all have the mathematical
301 * property of being suffix-free (or prefix-free in case of prefixes)
302 * so that no matter what number we concatenate the affix with, that we
303 * always reliably get unique numbers as result after concatenation.
304 */
305 typedef struct VariLenAffix {
306 AffixType_t type; /* Whether this affix is a suffix or a prefix. */
307 uint64_t value; /* Actual numerical value of this affix. */
308 /*
309 * Lenght of the affix, that is how many (of the lowest) bits of @c value
310 * must be used for appending/prepending this affix to its final resulting,
311 * unique number.
312 */
313 int bits;
314 } VariLenAffix;
315
316 /* See qid_inode_prefix_hash_bits(). */
317 typedef struct {
318 dev_t dev; /* FS device on host. */
319 /*
320 * How many (high) bits of the original inode number shall be used for
321 * hashing.
322 */
323 int prefix_bits;
324 } QpdEntry;
325
326 /* QID path prefix entry, see stat_to_qid */
327 typedef struct {
328 dev_t dev;
329 uint16_t ino_prefix;
330 uint32_t qp_affix_index;
331 VariLenAffix qp_affix;
332 } QppEntry;
333
334 /* QID path full entry, as above */
335 typedef struct {
336 dev_t dev;
337 ino_t ino;
338 uint64_t path;
339 } QpfEntry;
340
341 struct V9fsState
342 {
343 QLIST_HEAD(, V9fsPDU) free_list;
344 QLIST_HEAD(, V9fsPDU) active_list;
345 V9fsFidState *fid_list;
346 FileOperations *ops;
347 FsContext ctx;
348 char *tag;
349 P9ProtoVersion proto_version;
350 int32_t msize;
351 V9fsPDU pdus[MAX_REQ];
352 const V9fsTransport *transport;
353 /*
354 * lock ensuring atomic path update
355 * on rename.
356 */
357 CoRwlock rename_lock;
358 int32_t root_fid;
359 Error *migration_blocker;
360 V9fsConf fsconf;
361 V9fsQID root_qid;
362 dev_t dev_id;
363 struct qht qpd_table;
364 struct qht qpp_table;
365 struct qht qpf_table;
366 uint64_t qp_ndevices; /* Amount of entries in qpd_table. */
367 uint16_t qp_affix_next;
368 uint64_t qp_fullpath_next;
369 };
370
371 /* 9p2000.L open flags */
372 #define P9_DOTL_RDONLY 00000000
373 #define P9_DOTL_WRONLY 00000001
374 #define P9_DOTL_RDWR 00000002
375 #define P9_DOTL_NOACCESS 00000003
376 #define P9_DOTL_CREATE 00000100
377 #define P9_DOTL_EXCL 00000200
378 #define P9_DOTL_NOCTTY 00000400
379 #define P9_DOTL_TRUNC 00001000
380 #define P9_DOTL_APPEND 00002000
381 #define P9_DOTL_NONBLOCK 00004000
382 #define P9_DOTL_DSYNC 00010000
383 #define P9_DOTL_FASYNC 00020000
384 #define P9_DOTL_DIRECT 00040000
385 #define P9_DOTL_LARGEFILE 00100000
386 #define P9_DOTL_DIRECTORY 00200000
387 #define P9_DOTL_NOFOLLOW 00400000
388 #define P9_DOTL_NOATIME 01000000
389 #define P9_DOTL_CLOEXEC 02000000
390 #define P9_DOTL_SYNC 04000000
391
392 /* 9p2000.L at flags */
393 #define P9_DOTL_AT_REMOVEDIR 0x200
394
395 /* 9P2000.L lock type */
396 #define P9_LOCK_TYPE_RDLCK 0
397 #define P9_LOCK_TYPE_WRLCK 1
398 #define P9_LOCK_TYPE_UNLCK 2
399
400 #define P9_LOCK_SUCCESS 0
401 #define P9_LOCK_BLOCKED 1
402 #define P9_LOCK_ERROR 2
403 #define P9_LOCK_GRACE 3
404
405 #define P9_LOCK_FLAGS_BLOCK 1
406 #define P9_LOCK_FLAGS_RECLAIM 2
407
408 typedef struct V9fsFlock
409 {
410 uint8_t type;
411 uint32_t flags;
412 uint64_t start; /* absolute offset */
413 uint64_t length;
414 uint32_t proc_id;
415 V9fsString client_id;
416 } V9fsFlock;
417
418 typedef struct V9fsGetlock
419 {
420 uint8_t type;
421 uint64_t start; /* absolute offset */
422 uint64_t length;
423 uint32_t proc_id;
424 V9fsString client_id;
425 } V9fsGetlock;
426
427 extern int open_fd_hw;
428 extern int total_open_fd;
429
430 static inline void v9fs_path_write_lock(V9fsState *s)
431 {
432 if (s->ctx.export_flags & V9FS_PATHNAME_FSCONTEXT) {
433 qemu_co_rwlock_wrlock(&s->rename_lock);
434 }
435 }
436
437 static inline void v9fs_path_read_lock(V9fsState *s)
438 {
439 if (s->ctx.export_flags & V9FS_PATHNAME_FSCONTEXT) {
440 qemu_co_rwlock_rdlock(&s->rename_lock);
441 }
442 }
443
444 static inline void v9fs_path_unlock(V9fsState *s)
445 {
446 if (s->ctx.export_flags & V9FS_PATHNAME_FSCONTEXT) {
447 qemu_co_rwlock_unlock(&s->rename_lock);
448 }
449 }
450
451 static inline uint8_t v9fs_request_cancelled(V9fsPDU *pdu)
452 {
453 return pdu->cancelled;
454 }
455
456 void coroutine_fn v9fs_reclaim_fd(V9fsPDU *pdu);
457 void v9fs_path_init(V9fsPath *path);
458 void v9fs_path_free(V9fsPath *path);
459 void v9fs_path_sprintf(V9fsPath *path, const char *fmt, ...);
460 void v9fs_path_copy(V9fsPath *dst, const V9fsPath *src);
461 size_t v9fs_readdir_response_size(V9fsString *name);
462 int v9fs_name_to_path(V9fsState *s, V9fsPath *dirpath,
463 const char *name, V9fsPath *path);
464 int v9fs_device_realize_common(V9fsState *s, const V9fsTransport *t,
465 Error **errp);
466 void v9fs_device_unrealize_common(V9fsState *s);
467
468 V9fsPDU *pdu_alloc(V9fsState *s);
469 void pdu_free(V9fsPDU *pdu);
470 void pdu_submit(V9fsPDU *pdu, P9MsgHeader *hdr);
471 void v9fs_reset(V9fsState *s);
472
473 struct V9fsTransport {
474 ssize_t (*pdu_vmarshal)(V9fsPDU *pdu, size_t offset, const char *fmt,
475 va_list ap);
476 ssize_t (*pdu_vunmarshal)(V9fsPDU *pdu, size_t offset, const char *fmt,
477 va_list ap);
478 void (*init_in_iov_from_pdu)(V9fsPDU *pdu, struct iovec **piov,
479 unsigned int *pniov, size_t size);
480 void (*init_out_iov_from_pdu)(V9fsPDU *pdu, struct iovec **piov,
481 unsigned int *pniov, size_t size);
482 void (*push_and_notify)(V9fsPDU *pdu);
483 };
484
485 #endif