9p.h (12209B)
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 * 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 uint32_t size; 148 uint16_t tag; 149 uint8_t id; 150 uint8_t cancelled; 151 CoQueue complete; 152 V9fsState *s; 153 QLIST_ENTRY(V9fsPDU) next; 154 uint32_t idx; 155 }; 156 157 158 /* FIXME 159 * 1) change user needs to set groups and stuff 160 */ 161 162 #define MAX_REQ 128 163 #define MAX_TAG_LEN 32 164 165 #define BUG_ON(cond) assert(!(cond)) 166 167 typedef struct V9fsFidState V9fsFidState; 168 169 enum { 170 P9_FID_NONE = 0, 171 P9_FID_FILE, 172 P9_FID_DIR, 173 P9_FID_XATTR, 174 }; 175 176 typedef struct V9fsConf 177 { 178 /* tag name for the device */ 179 char *tag; 180 char *fsdev_id; 181 } V9fsConf; 182 183 /* 9p2000.L xattr flags (matches Linux values) */ 184 #define P9_XATTR_CREATE 1 185 #define P9_XATTR_REPLACE 2 186 187 typedef struct V9fsXattr 188 { 189 uint64_t copied_len; 190 uint64_t len; 191 void *value; 192 V9fsString name; 193 int flags; 194 bool xattrwalk_fid; 195 } V9fsXattr; 196 197 typedef struct V9fsDir { 198 DIR *stream; 199 P9ProtoVersion proto_version; 200 /* readdir mutex type used for 9P2000.u protocol variant */ 201 CoMutex readdir_mutex_u; 202 /* readdir mutex type used for 9P2000.L protocol variant */ 203 QemuMutex readdir_mutex_L; 204 } V9fsDir; 205 206 static inline void v9fs_readdir_lock(V9fsDir *dir) 207 { 208 if (dir->proto_version == V9FS_PROTO_2000U) { 209 qemu_co_mutex_lock(&dir->readdir_mutex_u); 210 } else { 211 qemu_mutex_lock(&dir->readdir_mutex_L); 212 } 213 } 214 215 static inline void v9fs_readdir_unlock(V9fsDir *dir) 216 { 217 if (dir->proto_version == V9FS_PROTO_2000U) { 218 qemu_co_mutex_unlock(&dir->readdir_mutex_u); 219 } else { 220 qemu_mutex_unlock(&dir->readdir_mutex_L); 221 } 222 } 223 224 static inline void v9fs_readdir_init(P9ProtoVersion proto_version, V9fsDir *dir) 225 { 226 dir->proto_version = proto_version; 227 if (proto_version == V9FS_PROTO_2000U) { 228 qemu_co_mutex_init(&dir->readdir_mutex_u); 229 } else { 230 qemu_mutex_init(&dir->readdir_mutex_L); 231 } 232 } 233 234 /* 235 * Type for 9p fs drivers' (a.k.a. 9p backends) result of readdir requests, 236 * which is a chained list of directory entries. 237 */ 238 typedef struct V9fsDirEnt { 239 /* mandatory (must not be NULL) information for all readdir requests */ 240 struct dirent *dent; 241 /* 242 * optional (may be NULL): A full stat of each directory entry is just 243 * done if explicitly told to fs driver. 244 */ 245 struct stat *st; 246 /* 247 * instead of an array, directory entries are always returned as 248 * chained list, that's because the amount of entries retrieved by fs 249 * drivers is dependent on the individual entries' name (since response 250 * messages are size limited), so the final amount cannot be estimated 251 * before hand 252 */ 253 struct V9fsDirEnt *next; 254 } V9fsDirEnt; 255 256 /* 257 * Filled by fs driver on open and other 258 * calls. 259 */ 260 union V9fsFidOpenState { 261 int fd; 262 V9fsDir dir; 263 V9fsXattr xattr; 264 /* 265 * private pointer for fs drivers, that 266 * have its own internal representation of 267 * open files. 268 */ 269 void *private; 270 }; 271 272 struct V9fsFidState { 273 int fid_type; 274 int32_t fid; 275 V9fsPath path; 276 V9fsFidOpenState fs; 277 V9fsFidOpenState fs_reclaim; 278 int flags; 279 int open_flags; 280 uid_t uid; 281 int ref; 282 bool clunked; 283 QSIMPLEQ_ENTRY(V9fsFidState) next; 284 QSLIST_ENTRY(V9fsFidState) reclaim_next; 285 }; 286 287 typedef enum AffixType_t { 288 AffixType_Prefix, 289 AffixType_Suffix, /* A.k.a. postfix. */ 290 } AffixType_t; 291 292 /* 293 * Unique affix of variable length. 294 * 295 * An affix is (currently) either a suffix or a prefix, which is either 296 * going to be prepended (prefix) or appended (suffix) with some other 297 * number for the goal to generate unique numbers. Accordingly the 298 * suffixes (or prefixes) we generate @b must all have the mathematical 299 * property of being suffix-free (or prefix-free in case of prefixes) 300 * so that no matter what number we concatenate the affix with, that we 301 * always reliably get unique numbers as result after concatenation. 302 */ 303 typedef struct VariLenAffix { 304 AffixType_t type; /* Whether this affix is a suffix or a prefix. */ 305 uint64_t value; /* Actual numerical value of this affix. */ 306 /* 307 * Lenght of the affix, that is how many (of the lowest) bits of ``value`` 308 * must be used for appending/prepending this affix to its final resulting, 309 * unique number. 310 */ 311 int bits; 312 } VariLenAffix; 313 314 /* See qid_inode_prefix_hash_bits(). */ 315 typedef struct { 316 dev_t dev; /* FS device on host. */ 317 /* 318 * How many (high) bits of the original inode number shall be used for 319 * hashing. 320 */ 321 int prefix_bits; 322 } QpdEntry; 323 324 /* QID path prefix entry, see stat_to_qid */ 325 typedef struct { 326 dev_t dev; 327 uint16_t ino_prefix; 328 uint32_t qp_affix_index; 329 VariLenAffix qp_affix; 330 } QppEntry; 331 332 /* QID path full entry, as above */ 333 typedef struct { 334 dev_t dev; 335 ino_t ino; 336 uint64_t path; 337 } QpfEntry; 338 339 struct V9fsState { 340 QLIST_HEAD(, V9fsPDU) free_list; 341 QLIST_HEAD(, V9fsPDU) active_list; 342 GHashTable *fids; 343 FileOperations *ops; 344 FsContext ctx; 345 char *tag; 346 P9ProtoVersion proto_version; 347 int32_t msize; 348 V9fsPDU pdus[MAX_REQ]; 349 const V9fsTransport *transport; 350 /* 351 * lock ensuring atomic path update 352 * on rename. 353 */ 354 CoRwlock rename_lock; 355 int32_t root_fid; 356 Error *migration_blocker; 357 V9fsConf fsconf; 358 struct stat root_st; 359 dev_t dev_id; 360 struct qht qpd_table; 361 struct qht qpp_table; 362 struct qht qpf_table; 363 uint64_t qp_ndevices; /* Amount of entries in qpd_table. */ 364 uint16_t qp_affix_next; 365 uint64_t qp_fullpath_next; 366 }; 367 368 /* 9p2000.L open flags */ 369 #define P9_DOTL_RDONLY 00000000 370 #define P9_DOTL_WRONLY 00000001 371 #define P9_DOTL_RDWR 00000002 372 #define P9_DOTL_NOACCESS 00000003 373 #define P9_DOTL_CREATE 00000100 374 #define P9_DOTL_EXCL 00000200 375 #define P9_DOTL_NOCTTY 00000400 376 #define P9_DOTL_TRUNC 00001000 377 #define P9_DOTL_APPEND 00002000 378 #define P9_DOTL_NONBLOCK 00004000 379 #define P9_DOTL_DSYNC 00010000 380 #define P9_DOTL_FASYNC 00020000 381 #define P9_DOTL_DIRECT 00040000 382 #define P9_DOTL_LARGEFILE 00100000 383 #define P9_DOTL_DIRECTORY 00200000 384 #define P9_DOTL_NOFOLLOW 00400000 385 #define P9_DOTL_NOATIME 01000000 386 #define P9_DOTL_CLOEXEC 02000000 387 #define P9_DOTL_SYNC 04000000 388 389 /* 9p2000.L at flags */ 390 #define P9_DOTL_AT_REMOVEDIR 0x200 391 392 /* 9P2000.L lock type */ 393 #define P9_LOCK_TYPE_RDLCK 0 394 #define P9_LOCK_TYPE_WRLCK 1 395 #define P9_LOCK_TYPE_UNLCK 2 396 397 #define P9_LOCK_SUCCESS 0 398 #define P9_LOCK_BLOCKED 1 399 #define P9_LOCK_ERROR 2 400 #define P9_LOCK_GRACE 3 401 402 #define P9_LOCK_FLAGS_BLOCK 1 403 #define P9_LOCK_FLAGS_RECLAIM 2 404 405 typedef struct V9fsFlock 406 { 407 uint8_t type; 408 uint32_t flags; 409 uint64_t start; /* absolute offset */ 410 uint64_t length; 411 uint32_t proc_id; 412 V9fsString client_id; 413 } V9fsFlock; 414 415 typedef struct V9fsGetlock 416 { 417 uint8_t type; 418 uint64_t start; /* absolute offset */ 419 uint64_t length; 420 uint32_t proc_id; 421 V9fsString client_id; 422 } V9fsGetlock; 423 424 extern int open_fd_hw; 425 extern int total_open_fd; 426 427 static inline void coroutine_fn 428 v9fs_path_write_lock(V9fsState *s) 429 { 430 if (s->ctx.export_flags & V9FS_PATHNAME_FSCONTEXT) { 431 qemu_co_rwlock_wrlock(&s->rename_lock); 432 } 433 } 434 435 static inline void coroutine_fn 436 v9fs_path_read_lock(V9fsState *s) 437 { 438 if (s->ctx.export_flags & V9FS_PATHNAME_FSCONTEXT) { 439 qemu_co_rwlock_rdlock(&s->rename_lock); 440 } 441 } 442 443 static inline void coroutine_fn 444 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