1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1989, 1991, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * @(#)mount.h 8.21 (Berkeley) 5/20/95 32 * $FreeBSD$ 33 */ 34 35 #ifndef _SYS_MOUNT_H_ 36 #define _SYS_MOUNT_H_ 37 38 #include <sys/ucred.h> 39 #include <sys/queue.h> 40 #ifdef _KERNEL 41 #include <sys/lock.h> 42 #include <sys/lockmgr.h> 43 #include <sys/tslog.h> 44 #include <sys/_mutex.h> 45 #include <sys/_sx.h> 46 #endif 47 48 /* 49 * NOTE: When changing statfs structure, mount structure, MNT_* flags or 50 * MNTK_* flags also update DDB show mount command in vfs_subr.c. 51 */ 52 53 typedef struct fsid { int32_t val[2]; } fsid_t; /* filesystem id type */ 54 55 #define fsidcmp(a, b) memcmp((a), (b), sizeof(fsid_t)) 56 57 /* 58 * File identifier. 59 * These are unique per filesystem on a single machine. 60 * 61 * Note that the offset of fid_data is 4 bytes, so care must be taken to avoid 62 * undefined behavior accessing unaligned fields within an embedded struct. 63 */ 64 #define MAXFIDSZ 16 65 66 struct fid { 67 u_short fid_len; /* length of data in bytes */ 68 u_short fid_data0; /* force longword alignment */ 69 char fid_data[MAXFIDSZ]; /* data (variable length) */ 70 }; 71 72 /* 73 * filesystem statistics 74 */ 75 #define MFSNAMELEN 16 /* length of type name including null */ 76 #define MNAMELEN 1024 /* size of on/from name bufs */ 77 #define STATFS_VERSION 0x20140518 /* current version number */ 78 struct statfs { 79 uint32_t f_version; /* structure version number */ 80 uint32_t f_type; /* type of filesystem */ 81 uint64_t f_flags; /* copy of mount exported flags */ 82 uint64_t f_bsize; /* filesystem fragment size */ 83 uint64_t f_iosize; /* optimal transfer block size */ 84 uint64_t f_blocks; /* total data blocks in filesystem */ 85 uint64_t f_bfree; /* free blocks in filesystem */ 86 int64_t f_bavail; /* free blocks avail to non-superuser */ 87 uint64_t f_files; /* total file nodes in filesystem */ 88 int64_t f_ffree; /* free nodes avail to non-superuser */ 89 uint64_t f_syncwrites; /* count of sync writes since mount */ 90 uint64_t f_asyncwrites; /* count of async writes since mount */ 91 uint64_t f_syncreads; /* count of sync reads since mount */ 92 uint64_t f_asyncreads; /* count of async reads since mount */ 93 uint64_t f_spare[10]; /* unused spare */ 94 uint32_t f_namemax; /* maximum filename length */ 95 uid_t f_owner; /* user that mounted the filesystem */ 96 fsid_t f_fsid; /* filesystem id */ 97 char f_charspare[80]; /* spare string space */ 98 char f_fstypename[MFSNAMELEN]; /* filesystem type name */ 99 char f_mntfromname[MNAMELEN]; /* mounted filesystem */ 100 char f_mntonname[MNAMELEN]; /* directory on which mounted */ 101 }; 102 103 #if defined(_WANT_FREEBSD11_STATFS) || defined(_KERNEL) 104 #define FREEBSD11_STATFS_VERSION 0x20030518 /* current version number */ 105 struct freebsd11_statfs { 106 uint32_t f_version; /* structure version number */ 107 uint32_t f_type; /* type of filesystem */ 108 uint64_t f_flags; /* copy of mount exported flags */ 109 uint64_t f_bsize; /* filesystem fragment size */ 110 uint64_t f_iosize; /* optimal transfer block size */ 111 uint64_t f_blocks; /* total data blocks in filesystem */ 112 uint64_t f_bfree; /* free blocks in filesystem */ 113 int64_t f_bavail; /* free blocks avail to non-superuser */ 114 uint64_t f_files; /* total file nodes in filesystem */ 115 int64_t f_ffree; /* free nodes avail to non-superuser */ 116 uint64_t f_syncwrites; /* count of sync writes since mount */ 117 uint64_t f_asyncwrites; /* count of async writes since mount */ 118 uint64_t f_syncreads; /* count of sync reads since mount */ 119 uint64_t f_asyncreads; /* count of async reads since mount */ 120 uint64_t f_spare[10]; /* unused spare */ 121 uint32_t f_namemax; /* maximum filename length */ 122 uid_t f_owner; /* user that mounted the filesystem */ 123 fsid_t f_fsid; /* filesystem id */ 124 char f_charspare[80]; /* spare string space */ 125 char f_fstypename[16]; /* filesystem type name */ 126 char f_mntfromname[88]; /* mounted filesystem */ 127 char f_mntonname[88]; /* directory on which mounted */ 128 }; 129 #endif /* _WANT_FREEBSD11_STATFS || _KERNEL */ 130 131 #ifdef _KERNEL 132 #define OMFSNAMELEN 16 /* length of fs type name, including null */ 133 #define OMNAMELEN (88 - 2 * sizeof(long)) /* size of on/from name bufs */ 134 135 /* XXX getfsstat.2 is out of date with write and read counter changes here. */ 136 /* XXX statfs.2 is out of date with read counter changes here. */ 137 struct ostatfs { 138 long f_spare2; /* placeholder */ 139 long f_bsize; /* fundamental filesystem block size */ 140 long f_iosize; /* optimal transfer block size */ 141 long f_blocks; /* total data blocks in filesystem */ 142 long f_bfree; /* free blocks in fs */ 143 long f_bavail; /* free blocks avail to non-superuser */ 144 long f_files; /* total file nodes in filesystem */ 145 long f_ffree; /* free file nodes in fs */ 146 fsid_t f_fsid; /* filesystem id */ 147 uid_t f_owner; /* user that mounted the filesystem */ 148 int f_type; /* type of filesystem */ 149 int f_flags; /* copy of mount exported flags */ 150 long f_syncwrites; /* count of sync writes since mount */ 151 long f_asyncwrites; /* count of async writes since mount */ 152 char f_fstypename[OMFSNAMELEN]; /* fs type name */ 153 char f_mntonname[OMNAMELEN]; /* directory on which mounted */ 154 long f_syncreads; /* count of sync reads since mount */ 155 long f_asyncreads; /* count of async reads since mount */ 156 short f_spares1; /* unused spare */ 157 char f_mntfromname[OMNAMELEN];/* mounted filesystem */ 158 short f_spares2; /* unused spare */ 159 /* 160 * XXX on machines where longs are aligned to 8-byte boundaries, there 161 * is an unnamed int32_t here. This spare was after the apparent end 162 * of the struct until we bit off the read counters from f_mntonname. 163 */ 164 long f_spare[2]; /* unused spare */ 165 }; 166 167 TAILQ_HEAD(vnodelst, vnode); 168 169 /* Mount options list */ 170 TAILQ_HEAD(vfsoptlist, vfsopt); 171 struct vfsopt { 172 TAILQ_ENTRY(vfsopt) link; 173 char *name; 174 void *value; 175 int len; 176 int pos; 177 int seen; 178 }; 179 180 /* 181 * Structure per mounted filesystem. Each mounted filesystem has an 182 * array of operations and an instance record. The filesystems are 183 * put on a doubly linked list. 184 * 185 * Lock reference: 186 * l - mnt_listmtx 187 * m - mountlist_mtx 188 * i - interlock 189 * v - vnode freelist mutex 190 * 191 * Unmarked fields are considered stable as long as a ref is held. 192 * 193 */ 194 struct mount { 195 struct mtx mnt_mtx; /* mount structure interlock */ 196 int mnt_gen; /* struct mount generation */ 197 #define mnt_startzero mnt_list 198 TAILQ_ENTRY(mount) mnt_list; /* (m) mount list */ 199 struct vfsops *mnt_op; /* operations on fs */ 200 struct vfsconf *mnt_vfc; /* configuration info */ 201 struct vnode *mnt_vnodecovered; /* vnode we mounted on */ 202 struct vnode *mnt_syncer; /* syncer vnode */ 203 int mnt_ref; /* (i) Reference count */ 204 struct vnodelst mnt_nvnodelist; /* (i) list of vnodes */ 205 int mnt_nvnodelistsize; /* (i) # of vnodes */ 206 int mnt_writeopcount; /* (i) write syscalls pending */ 207 int mnt_kern_flag; /* (i) kernel only flags */ 208 uint64_t mnt_flag; /* (i) flags shared with user */ 209 struct vfsoptlist *mnt_opt; /* current mount options */ 210 struct vfsoptlist *mnt_optnew; /* new options passed to fs */ 211 int mnt_maxsymlinklen; /* max size of short symlink */ 212 struct statfs mnt_stat; /* cache of filesystem stats */ 213 struct ucred *mnt_cred; /* credentials of mounter */ 214 void * mnt_data; /* private data */ 215 time_t mnt_time; /* last time written*/ 216 int mnt_iosize_max; /* max size for clusters, etc */ 217 struct netexport *mnt_export; /* export list */ 218 struct label *mnt_label; /* MAC label for the fs */ 219 u_int mnt_hashseed; /* Random seed for vfs_hash */ 220 int mnt_lockref; /* (i) Lock reference count */ 221 int mnt_secondary_writes; /* (i) # of secondary writes */ 222 int mnt_secondary_accwrites;/* (i) secondary wr. starts */ 223 struct thread *mnt_susp_owner; /* (i) thread owning suspension */ 224 #define mnt_endzero mnt_gjprovider 225 char *mnt_gjprovider; /* gjournal provider name */ 226 struct mtx mnt_listmtx; 227 struct vnodelst mnt_lazyvnodelist; /* (l) list of lazy vnodes */ 228 int mnt_lazyvnodelistsize; /* (l) # of lazy vnodes */ 229 struct lock mnt_explock; /* vfs_export walkers lock */ 230 TAILQ_ENTRY(mount) mnt_upper_link; /* (m) we in the all uppers */ 231 TAILQ_HEAD(, mount) mnt_uppers; /* (m) upper mounts over us*/ 232 int __aligned(CACHE_LINE_SIZE) mnt_vfs_ops;/* (i) pending vfs ops */ 233 int *mnt_thread_in_ops_pcpu; 234 int *mnt_ref_pcpu; 235 int *mnt_lockref_pcpu; 236 int *mnt_writeopcount_pcpu; 237 struct vnode *mnt_rootvnode; 238 }; 239 240 /* 241 * Definitions for MNT_VNODE_FOREACH_ALL. 242 */ 243 struct vnode *__mnt_vnode_next_all(struct vnode **mvp, struct mount *mp); 244 struct vnode *__mnt_vnode_first_all(struct vnode **mvp, struct mount *mp); 245 void __mnt_vnode_markerfree_all(struct vnode **mvp, struct mount *mp); 246 247 #define MNT_VNODE_FOREACH_ALL(vp, mp, mvp) \ 248 for (vp = __mnt_vnode_first_all(&(mvp), (mp)); \ 249 (vp) != NULL; vp = __mnt_vnode_next_all(&(mvp), (mp))) 250 251 #define MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp) \ 252 do { \ 253 MNT_ILOCK(mp); \ 254 __mnt_vnode_markerfree_all(&(mvp), (mp)); \ 255 /* MNT_IUNLOCK(mp); -- done in above function */ \ 256 mtx_assert(MNT_MTX(mp), MA_NOTOWNED); \ 257 } while (0) 258 259 /* 260 * Definitions for MNT_VNODE_FOREACH_LAZY. 261 */ 262 typedef int mnt_lazy_cb_t(struct vnode *, void *); 263 struct vnode *__mnt_vnode_next_lazy(struct vnode **mvp, struct mount *mp, 264 mnt_lazy_cb_t *cb, void *cbarg); 265 struct vnode *__mnt_vnode_first_lazy(struct vnode **mvp, struct mount *mp, 266 mnt_lazy_cb_t *cb, void *cbarg); 267 void __mnt_vnode_markerfree_lazy(struct vnode **mvp, struct mount *mp); 268 269 #define MNT_VNODE_FOREACH_LAZY(vp, mp, mvp, cb, cbarg) \ 270 for (vp = __mnt_vnode_first_lazy(&(mvp), (mp), (cb), (cbarg)); \ 271 (vp) != NULL; \ 272 vp = __mnt_vnode_next_lazy(&(mvp), (mp), (cb), (cbarg))) 273 274 #define MNT_VNODE_FOREACH_LAZY_ABORT(mp, mvp) \ 275 __mnt_vnode_markerfree_lazy(&(mvp), (mp)) 276 277 #define MNT_ILOCK(mp) mtx_lock(&(mp)->mnt_mtx) 278 #define MNT_ITRYLOCK(mp) mtx_trylock(&(mp)->mnt_mtx) 279 #define MNT_IUNLOCK(mp) mtx_unlock(&(mp)->mnt_mtx) 280 #define MNT_MTX(mp) (&(mp)->mnt_mtx) 281 282 #define MNT_REF(mp) do { \ 283 mtx_assert(MNT_MTX(mp), MA_OWNED); \ 284 mp->mnt_ref++; \ 285 } while (0) 286 #define MNT_REL(mp) do { \ 287 mtx_assert(MNT_MTX(mp), MA_OWNED); \ 288 (mp)->mnt_ref--; \ 289 if ((mp)->mnt_vfs_ops && (mp)->mnt_ref < 0) \ 290 vfs_dump_mount_counters(mp); \ 291 if ((mp)->mnt_ref == 0 && (mp)->mnt_vfs_ops) \ 292 wakeup((mp)); \ 293 } while (0) 294 295 #endif /* _KERNEL */ 296 297 /* 298 * User specifiable flags, stored in mnt_flag. 299 */ 300 #define MNT_RDONLY 0x0000000000000001ULL /* read only filesystem */ 301 #define MNT_SYNCHRONOUS 0x0000000000000002ULL /* fs written synchronously */ 302 #define MNT_NOEXEC 0x0000000000000004ULL /* can't exec from filesystem */ 303 #define MNT_NOSUID 0x0000000000000008ULL /* don't honor setuid fs bits */ 304 #define MNT_NFS4ACLS 0x0000000000000010ULL /* enable NFS version 4 ACLs */ 305 #define MNT_UNION 0x0000000000000020ULL /* union with underlying fs */ 306 #define MNT_ASYNC 0x0000000000000040ULL /* fs written asynchronously */ 307 #define MNT_SUIDDIR 0x0000000000100000ULL /* special SUID dir handling */ 308 #define MNT_SOFTDEP 0x0000000000200000ULL /* using soft updates */ 309 #define MNT_NOSYMFOLLOW 0x0000000000400000ULL /* do not follow symlinks */ 310 #define MNT_GJOURNAL 0x0000000002000000ULL /* GEOM journal support enabled */ 311 #define MNT_MULTILABEL 0x0000000004000000ULL /* MAC support for objects */ 312 #define MNT_ACLS 0x0000000008000000ULL /* ACL support enabled */ 313 #define MNT_NOATIME 0x0000000010000000ULL /* dont update file access time */ 314 #define MNT_NOCLUSTERR 0x0000000040000000ULL /* disable cluster read */ 315 #define MNT_NOCLUSTERW 0x0000000080000000ULL /* disable cluster write */ 316 #define MNT_SUJ 0x0000000100000000ULL /* using journaled soft updates */ 317 #define MNT_AUTOMOUNTED 0x0000000200000000ULL /* mounted by automountd(8) */ 318 #define MNT_UNTRUSTED 0x0000000800000000ULL /* filesys metadata untrusted */ 319 320 /* 321 * NFS export related mount flags. 322 */ 323 #define MNT_EXRDONLY 0x0000000000000080ULL /* exported read only */ 324 #define MNT_EXPORTED 0x0000000000000100ULL /* filesystem is exported */ 325 #define MNT_DEFEXPORTED 0x0000000000000200ULL /* exported to the world */ 326 #define MNT_EXPORTANON 0x0000000000000400ULL /* anon uid mapping for all */ 327 #define MNT_EXKERB 0x0000000000000800ULL /* exported with Kerberos */ 328 #define MNT_EXPUBLIC 0x0000000020000000ULL /* public export (WebNFS) */ 329 330 /* 331 * Flags set by internal operations, 332 * but visible to the user. 333 * XXX some of these are not quite right.. (I've never seen the root flag set) 334 */ 335 #define MNT_LOCAL 0x0000000000001000ULL /* filesystem is stored locally */ 336 #define MNT_QUOTA 0x0000000000002000ULL /* quotas are enabled on fs */ 337 #define MNT_ROOTFS 0x0000000000004000ULL /* identifies the root fs */ 338 #define MNT_USER 0x0000000000008000ULL /* mounted by a user */ 339 #define MNT_IGNORE 0x0000000000800000ULL /* do not show entry in df */ 340 #define MNT_VERIFIED 0x0000000400000000ULL /* filesystem is verified */ 341 342 /* 343 * Mask of flags that are visible to statfs(). 344 * XXX I think that this could now become (~(MNT_CMDFLAGS)) 345 * but the 'mount' program may need changing to handle this. 346 */ 347 #define MNT_VISFLAGMASK (MNT_RDONLY | MNT_SYNCHRONOUS | MNT_NOEXEC | \ 348 MNT_NOSUID | MNT_UNION | MNT_SUJ | \ 349 MNT_ASYNC | MNT_EXRDONLY | MNT_EXPORTED | \ 350 MNT_DEFEXPORTED | MNT_EXPORTANON| MNT_EXKERB | \ 351 MNT_LOCAL | MNT_USER | MNT_QUOTA | \ 352 MNT_ROOTFS | MNT_NOATIME | MNT_NOCLUSTERR| \ 353 MNT_NOCLUSTERW | MNT_SUIDDIR | MNT_SOFTDEP | \ 354 MNT_IGNORE | MNT_EXPUBLIC | MNT_NOSYMFOLLOW | \ 355 MNT_GJOURNAL | MNT_MULTILABEL | MNT_ACLS | \ 356 MNT_NFS4ACLS | MNT_AUTOMOUNTED | MNT_VERIFIED | \ 357 MNT_UNTRUSTED) 358 359 /* Mask of flags that can be updated. */ 360 #define MNT_UPDATEMASK (MNT_NOSUID | MNT_NOEXEC | \ 361 MNT_SYNCHRONOUS | MNT_UNION | MNT_ASYNC | \ 362 MNT_NOATIME | \ 363 MNT_NOSYMFOLLOW | MNT_IGNORE | \ 364 MNT_NOCLUSTERR | MNT_NOCLUSTERW | MNT_SUIDDIR | \ 365 MNT_ACLS | MNT_USER | MNT_NFS4ACLS | \ 366 MNT_AUTOMOUNTED | MNT_UNTRUSTED) 367 368 /* 369 * External filesystem command modifier flags. 370 * Unmount can use the MNT_FORCE flag. 371 * XXX: These are not STATES and really should be somewhere else. 372 * XXX: MNT_BYFSID and MNT_NONBUSY collide with MNT_ACLS and MNT_MULTILABEL, 373 * but because MNT_ACLS and MNT_MULTILABEL are only used for mount(2), 374 * and MNT_BYFSID and MNT_NONBUSY are only used for unmount(2), 375 * it's harmless. 376 */ 377 #define MNT_UPDATE 0x0000000000010000ULL /* not real mount, just update */ 378 #define MNT_DELEXPORT 0x0000000000020000ULL /* delete export host lists */ 379 #define MNT_RELOAD 0x0000000000040000ULL /* reload filesystem data */ 380 #define MNT_FORCE 0x0000000000080000ULL /* force unmount or readonly */ 381 #define MNT_SNAPSHOT 0x0000000001000000ULL /* snapshot the filesystem */ 382 #define MNT_NONBUSY 0x0000000004000000ULL /* check vnode use counts. */ 383 #define MNT_BYFSID 0x0000000008000000ULL /* specify filesystem by ID. */ 384 #define MNT_NOCOVER 0x0000001000000000ULL /* Do not cover a mount point */ 385 #define MNT_EMPTYDIR 0x0000002000000000ULL /* Only mount on empty dir */ 386 #define MNT_CMDFLAGS (MNT_UPDATE | MNT_DELEXPORT | MNT_RELOAD | \ 387 MNT_FORCE | MNT_SNAPSHOT | MNT_NONBUSY | \ 388 MNT_BYFSID | MNT_NOCOVER | MNT_EMPTYDIR) 389 /* 390 * Internal filesystem control flags stored in mnt_kern_flag. 391 * 392 * MNTK_UNMOUNT locks the mount entry so that name lookup cannot 393 * proceed past the mount point. This keeps the subtree stable during 394 * mounts and unmounts. When non-forced unmount flushes all vnodes 395 * from the mp queue, the MNTK_UNMOUNT flag prevents insmntque() from 396 * queueing new vnodes. 397 * 398 * MNTK_UNMOUNTF permits filesystems to detect a forced unmount while 399 * dounmount() is still waiting to lock the mountpoint. This allows 400 * the filesystem to cancel operations that might otherwise deadlock 401 * with the unmount attempt (used by NFS). 402 */ 403 #define MNTK_UNMOUNTF 0x00000001 /* forced unmount in progress */ 404 #define MNTK_ASYNC 0x00000002 /* filtered async flag */ 405 #define MNTK_SOFTDEP 0x00000004 /* async disabled by softdep */ 406 #define MNTK_NOMSYNC 0x00000008 /* don't do msync */ 407 #define MNTK_DRAINING 0x00000010 /* lock draining is happening */ 408 #define MNTK_REFEXPIRE 0x00000020 /* refcount expiring is happening */ 409 #define MNTK_EXTENDED_SHARED 0x00000040 /* Allow shared locking for more ops */ 410 #define MNTK_SHARED_WRITES 0x00000080 /* Allow shared locking for writes */ 411 #define MNTK_NO_IOPF 0x00000100 /* Disallow page faults during reads 412 and writes. Filesystem shall properly 413 handle i/o state on EFAULT. */ 414 #define MNTK_VGONE_UPPER 0x00000200 415 #define MNTK_VGONE_WAITER 0x00000400 416 #define MNTK_LOOKUP_EXCL_DOTDOT 0x00000800 417 #define MNTK_MARKER 0x00001000 418 #define MNTK_UNMAPPED_BUFS 0x00002000 419 #define MNTK_USES_BCACHE 0x00004000 /* FS uses the buffer cache. */ 420 #define MNTK_TEXT_REFS 0x00008000 /* Keep use ref for text */ 421 #define MNTK_VMSETSIZE_BUG 0x00010000 422 #define MNTK_UNIONFS 0x00020000 /* A hack for F_ISUNIONSTACK */ 423 #define MNTK_NOASYNC 0x00800000 /* disable async */ 424 #define MNTK_UNMOUNT 0x01000000 /* unmount in progress */ 425 #define MNTK_MWAIT 0x02000000 /* waiting for unmount to finish */ 426 #define MNTK_SUSPEND 0x08000000 /* request write suspension */ 427 #define MNTK_SUSPEND2 0x04000000 /* block secondary writes */ 428 #define MNTK_SUSPENDED 0x10000000 /* write operations are suspended */ 429 #define MNTK_NULL_NOCACHE 0x20000000 /* auto disable cache for nullfs 430 mounts over this fs */ 431 #define MNTK_LOOKUP_SHARED 0x40000000 /* FS supports shared lock lookups */ 432 #define MNTK_NOKNOTE 0x80000000 /* Don't send KNOTEs from VOP hooks */ 433 434 #ifdef _KERNEL 435 static inline int 436 MNT_SHARED_WRITES(struct mount *mp) 437 { 438 439 return (mp != NULL && (mp->mnt_kern_flag & MNTK_SHARED_WRITES) != 0); 440 } 441 442 static inline int 443 MNT_EXTENDED_SHARED(struct mount *mp) 444 { 445 446 return (mp != NULL && (mp->mnt_kern_flag & MNTK_EXTENDED_SHARED) != 0); 447 } 448 #endif 449 450 /* 451 * Sysctl CTL_VFS definitions. 452 * 453 * Second level identifier specifies which filesystem. Second level 454 * identifier VFS_VFSCONF returns information about all filesystems. 455 * Second level identifier VFS_GENERIC is non-terminal. 456 */ 457 #define VFS_VFSCONF 0 /* get configured filesystems */ 458 #define VFS_GENERIC 0 /* generic filesystem information */ 459 /* 460 * Third level identifiers for VFS_GENERIC are given below; third 461 * level identifiers for specific filesystems are given in their 462 * mount specific header files. 463 */ 464 #define VFS_MAXTYPENUM 1 /* int: highest defined filesystem type */ 465 #define VFS_CONF 2 /* struct: vfsconf for filesystem given 466 as next argument */ 467 468 /* 469 * Flags for various system call interfaces. 470 * 471 * waitfor flags to vfs_sync() and getfsstat() 472 */ 473 #define MNT_WAIT 1 /* synchronously wait for I/O to complete */ 474 #define MNT_NOWAIT 2 /* start all I/O, but do not wait for it */ 475 #define MNT_LAZY 3 /* push data not written by filesystem syncer */ 476 #define MNT_SUSPEND 4 /* Suspend file system after sync */ 477 478 /* 479 * Generic file handle 480 */ 481 struct fhandle { 482 fsid_t fh_fsid; /* Filesystem id of mount point */ 483 struct fid fh_fid; /* Filesys specific id */ 484 }; 485 typedef struct fhandle fhandle_t; 486 487 /* 488 * Old export arguments without security flavor list 489 */ 490 struct oexport_args { 491 int ex_flags; /* export related flags */ 492 uid_t ex_root; /* mapping for root uid */ 493 struct xucred ex_anon; /* mapping for anonymous user */ 494 struct sockaddr *ex_addr; /* net address to which exported */ 495 u_char ex_addrlen; /* and the net address length */ 496 struct sockaddr *ex_mask; /* mask of valid bits in saddr */ 497 u_char ex_masklen; /* and the smask length */ 498 char *ex_indexfile; /* index file for WebNFS URLs */ 499 }; 500 501 /* 502 * Export arguments for local filesystem mount calls. 503 */ 504 #define MAXSECFLAVORS 5 505 struct export_args { 506 int ex_flags; /* export related flags */ 507 uid_t ex_root; /* mapping for root uid */ 508 struct xucred ex_anon; /* mapping for anonymous user */ 509 struct sockaddr *ex_addr; /* net address to which exported */ 510 u_char ex_addrlen; /* and the net address length */ 511 struct sockaddr *ex_mask; /* mask of valid bits in saddr */ 512 u_char ex_masklen; /* and the smask length */ 513 char *ex_indexfile; /* index file for WebNFS URLs */ 514 int ex_numsecflavors; /* security flavor count */ 515 int ex_secflavors[MAXSECFLAVORS]; /* list of security flavors */ 516 }; 517 518 /* 519 * Structure holding information for a publicly exported filesystem 520 * (WebNFS). Currently the specs allow just for one such filesystem. 521 */ 522 struct nfs_public { 523 int np_valid; /* Do we hold valid information */ 524 fhandle_t np_handle; /* Filehandle for pub fs (internal) */ 525 struct mount *np_mount; /* Mountpoint of exported fs */ 526 char *np_index; /* Index file */ 527 }; 528 529 /* 530 * Filesystem configuration information. One of these exists for each 531 * type of filesystem supported by the kernel. These are searched at 532 * mount time to identify the requested filesystem. 533 * 534 * XXX: Never change the first two arguments! 535 */ 536 struct vfsconf { 537 u_int vfc_version; /* ABI version number */ 538 char vfc_name[MFSNAMELEN]; /* filesystem type name */ 539 struct vfsops *vfc_vfsops; /* filesystem operations vector */ 540 struct vfsops *vfc_vfsops_sd; /* ... signal-deferred */ 541 int vfc_typenum; /* historic filesystem type number */ 542 int vfc_refcount; /* number mounted of this type */ 543 int vfc_flags; /* permanent flags */ 544 int vfc_prison_flag; /* prison allow.mount.* flag */ 545 struct vfsoptdecl *vfc_opts; /* mount options */ 546 TAILQ_ENTRY(vfsconf) vfc_list; /* list of vfscons */ 547 }; 548 549 /* Userland version of the struct vfsconf. */ 550 struct xvfsconf { 551 struct vfsops *vfc_vfsops; /* filesystem operations vector */ 552 char vfc_name[MFSNAMELEN]; /* filesystem type name */ 553 int vfc_typenum; /* historic filesystem type number */ 554 int vfc_refcount; /* number mounted of this type */ 555 int vfc_flags; /* permanent flags */ 556 struct vfsconf *vfc_next; /* next in list */ 557 }; 558 559 #ifndef BURN_BRIDGES 560 struct ovfsconf { 561 void *vfc_vfsops; 562 char vfc_name[32]; 563 int vfc_index; 564 int vfc_refcount; 565 int vfc_flags; 566 }; 567 #endif 568 569 /* 570 * NB: these flags refer to IMPLEMENTATION properties, not properties of 571 * any actual mounts; i.e., it does not make sense to change the flags. 572 */ 573 #define VFCF_STATIC 0x00010000 /* statically compiled into kernel */ 574 #define VFCF_NETWORK 0x00020000 /* may get data over the network */ 575 #define VFCF_READONLY 0x00040000 /* writes are not implemented */ 576 #define VFCF_SYNTHETIC 0x00080000 /* data does not represent real files */ 577 #define VFCF_LOOPBACK 0x00100000 /* aliases some other mounted FS */ 578 #define VFCF_UNICODE 0x00200000 /* stores file names as Unicode */ 579 #define VFCF_JAIL 0x00400000 /* can be mounted from within a jail */ 580 #define VFCF_DELEGADMIN 0x00800000 /* supports delegated administration */ 581 #define VFCF_SBDRY 0x01000000 /* Stop at Boundary: defer stop requests 582 to kernel->user (AST) transition */ 583 584 typedef uint32_t fsctlop_t; 585 586 struct vfsidctl { 587 int vc_vers; /* should be VFSIDCTL_VERS1 (below) */ 588 fsid_t vc_fsid; /* fsid to operate on */ 589 char vc_fstypename[MFSNAMELEN]; 590 /* type of fs 'nfs' or '*' */ 591 fsctlop_t vc_op; /* operation VFS_CTL_* (below) */ 592 void *vc_ptr; /* pointer to data structure */ 593 size_t vc_len; /* sizeof said structure */ 594 u_int32_t vc_spare[12]; /* spare (must be zero) */ 595 }; 596 597 /* vfsidctl API version. */ 598 #define VFS_CTL_VERS1 0x01 599 600 /* 601 * New style VFS sysctls, do not reuse/conflict with the namespace for 602 * private sysctls. 603 * All "global" sysctl ops have the 33rd bit set: 604 * 0x...1.... 605 * Private sysctl ops should have the 33rd bit unset. 606 */ 607 #define VFS_CTL_QUERY 0x00010001 /* anything wrong? (vfsquery) */ 608 #define VFS_CTL_TIMEO 0x00010002 /* set timeout for vfs notification */ 609 #define VFS_CTL_NOLOCKS 0x00010003 /* disable file locking */ 610 611 struct vfsquery { 612 u_int32_t vq_flags; 613 u_int32_t vq_spare[31]; 614 }; 615 616 /* vfsquery flags */ 617 #define VQ_NOTRESP 0x0001 /* server down */ 618 #define VQ_NEEDAUTH 0x0002 /* server bad auth */ 619 #define VQ_LOWDISK 0x0004 /* we're low on space */ 620 #define VQ_MOUNT 0x0008 /* new filesystem arrived */ 621 #define VQ_UNMOUNT 0x0010 /* filesystem has left */ 622 #define VQ_DEAD 0x0020 /* filesystem is dead, needs force unmount */ 623 #define VQ_ASSIST 0x0040 /* filesystem needs assistance from external 624 program */ 625 #define VQ_NOTRESPLOCK 0x0080 /* server lockd down */ 626 #define VQ_FLAG0100 0x0100 /* placeholder */ 627 #define VQ_FLAG0200 0x0200 /* placeholder */ 628 #define VQ_FLAG0400 0x0400 /* placeholder */ 629 #define VQ_FLAG0800 0x0800 /* placeholder */ 630 #define VQ_FLAG1000 0x1000 /* placeholder */ 631 #define VQ_FLAG2000 0x2000 /* placeholder */ 632 #define VQ_FLAG4000 0x4000 /* placeholder */ 633 #define VQ_FLAG8000 0x8000 /* placeholder */ 634 635 #ifdef _KERNEL 636 /* Point a sysctl request at a vfsidctl's data. */ 637 #define VCTLTOREQ(vc, req) \ 638 do { \ 639 (req)->newptr = (vc)->vc_ptr; \ 640 (req)->newlen = (vc)->vc_len; \ 641 (req)->newidx = 0; \ 642 } while (0) 643 #endif 644 645 struct iovec; 646 struct uio; 647 648 #ifdef _KERNEL 649 650 /* 651 * vfs_busy specific flags and mask. 652 */ 653 #define MBF_NOWAIT 0x01 654 #define MBF_MNTLSTLOCK 0x02 655 #define MBF_MASK (MBF_NOWAIT | MBF_MNTLSTLOCK) 656 657 #ifdef MALLOC_DECLARE 658 MALLOC_DECLARE(M_MOUNT); 659 MALLOC_DECLARE(M_STATFS); 660 #endif 661 extern int maxvfsconf; /* highest defined filesystem type */ 662 663 TAILQ_HEAD(vfsconfhead, vfsconf); 664 extern struct vfsconfhead vfsconf; 665 666 /* 667 * Operations supported on mounted filesystem. 668 */ 669 struct mount_args; 670 struct nameidata; 671 struct sysctl_req; 672 struct mntarg; 673 674 /* 675 * N.B., vfs_cmount is the ancient vfsop invoked by the old mount(2) syscall. 676 * The new way is vfs_mount. 677 * 678 * vfs_cmount implementations typically translate arguments from their 679 * respective old per-FS structures into the key-value list supported by 680 * nmount(2), then use kernel_mount(9) to mimic nmount(2) from kernelspace. 681 * 682 * Filesystems with mounters that use nmount(2) do not need to and should not 683 * implement vfs_cmount. Hopefully a future cleanup can remove vfs_cmount and 684 * mount(2) entirely. 685 */ 686 typedef int vfs_cmount_t(struct mntarg *ma, void *data, uint64_t flags); 687 typedef int vfs_unmount_t(struct mount *mp, int mntflags); 688 typedef int vfs_root_t(struct mount *mp, int flags, struct vnode **vpp); 689 typedef int vfs_quotactl_t(struct mount *mp, int cmds, uid_t uid, void *arg); 690 typedef int vfs_statfs_t(struct mount *mp, struct statfs *sbp); 691 typedef int vfs_sync_t(struct mount *mp, int waitfor); 692 typedef int vfs_vget_t(struct mount *mp, ino_t ino, int flags, 693 struct vnode **vpp); 694 typedef int vfs_fhtovp_t(struct mount *mp, struct fid *fhp, 695 int flags, struct vnode **vpp); 696 typedef int vfs_checkexp_t(struct mount *mp, struct sockaddr *nam, 697 int *extflagsp, struct ucred **credanonp, 698 int *numsecflavors, int **secflavors); 699 typedef int vfs_init_t(struct vfsconf *); 700 typedef int vfs_uninit_t(struct vfsconf *); 701 typedef int vfs_extattrctl_t(struct mount *mp, int cmd, 702 struct vnode *filename_vp, int attrnamespace, 703 const char *attrname); 704 typedef int vfs_mount_t(struct mount *mp); 705 typedef int vfs_sysctl_t(struct mount *mp, fsctlop_t op, 706 struct sysctl_req *req); 707 typedef void vfs_susp_clean_t(struct mount *mp); 708 typedef void vfs_notify_lowervp_t(struct mount *mp, struct vnode *lowervp); 709 typedef void vfs_purge_t(struct mount *mp); 710 711 struct vfsops { 712 vfs_mount_t *vfs_mount; 713 vfs_cmount_t *vfs_cmount; 714 vfs_unmount_t *vfs_unmount; 715 vfs_root_t *vfs_root; 716 vfs_root_t *vfs_cachedroot; 717 vfs_quotactl_t *vfs_quotactl; 718 vfs_statfs_t *vfs_statfs; 719 vfs_sync_t *vfs_sync; 720 vfs_vget_t *vfs_vget; 721 vfs_fhtovp_t *vfs_fhtovp; 722 vfs_checkexp_t *vfs_checkexp; 723 vfs_init_t *vfs_init; 724 vfs_uninit_t *vfs_uninit; 725 vfs_extattrctl_t *vfs_extattrctl; 726 vfs_sysctl_t *vfs_sysctl; 727 vfs_susp_clean_t *vfs_susp_clean; 728 vfs_notify_lowervp_t *vfs_reclaim_lowervp; 729 vfs_notify_lowervp_t *vfs_unlink_lowervp; 730 vfs_purge_t *vfs_purge; 731 vfs_mount_t *vfs_spare[6]; /* spares for ABI compat */ 732 }; 733 734 vfs_statfs_t __vfs_statfs; 735 736 #define VFS_MOUNT(MP) ({ \ 737 int _rc; \ 738 \ 739 TSRAW(curthread, TS_ENTER, "VFS_MOUNT", (MP)->mnt_vfc->vfc_name);\ 740 _rc = (*(MP)->mnt_op->vfs_mount)(MP); \ 741 TSRAW(curthread, TS_EXIT, "VFS_MOUNT", (MP)->mnt_vfc->vfc_name);\ 742 _rc; }) 743 744 #define VFS_UNMOUNT(MP, FORCE) ({ \ 745 int _rc; \ 746 \ 747 _rc = (*(MP)->mnt_op->vfs_unmount)(MP, FORCE); \ 748 _rc; }) 749 750 #define VFS_ROOT(MP, FLAGS, VPP) ({ \ 751 int _rc; \ 752 \ 753 _rc = (*(MP)->mnt_op->vfs_root)(MP, FLAGS, VPP); \ 754 _rc; }) 755 756 #define VFS_CACHEDROOT(MP, FLAGS, VPP) ({ \ 757 int _rc; \ 758 \ 759 _rc = (*(MP)->mnt_op->vfs_cachedroot)(MP, FLAGS, VPP); \ 760 _rc; }) 761 762 #define VFS_QUOTACTL(MP, C, U, A) ({ \ 763 int _rc; \ 764 \ 765 _rc = (*(MP)->mnt_op->vfs_quotactl)(MP, C, U, A); \ 766 _rc; }) 767 768 #define VFS_STATFS(MP, SBP) ({ \ 769 int _rc; \ 770 \ 771 _rc = __vfs_statfs((MP), (SBP)); \ 772 _rc; }) 773 774 #define VFS_SYNC(MP, WAIT) ({ \ 775 int _rc; \ 776 \ 777 _rc = (*(MP)->mnt_op->vfs_sync)(MP, WAIT); \ 778 _rc; }) 779 780 #define VFS_VGET(MP, INO, FLAGS, VPP) ({ \ 781 int _rc; \ 782 \ 783 _rc = (*(MP)->mnt_op->vfs_vget)(MP, INO, FLAGS, VPP); \ 784 _rc; }) 785 786 #define VFS_FHTOVP(MP, FIDP, FLAGS, VPP) ({ \ 787 int _rc; \ 788 \ 789 _rc = (*(MP)->mnt_op->vfs_fhtovp)(MP, FIDP, FLAGS, VPP); \ 790 _rc; }) 791 792 #define VFS_CHECKEXP(MP, NAM, EXFLG, CRED, NUMSEC, SEC) ({ \ 793 int _rc; \ 794 \ 795 _rc = (*(MP)->mnt_op->vfs_checkexp)(MP, NAM, EXFLG, CRED, NUMSEC,\ 796 SEC); \ 797 _rc; }) 798 799 #define VFS_EXTATTRCTL(MP, C, FN, NS, N) ({ \ 800 int _rc; \ 801 \ 802 _rc = (*(MP)->mnt_op->vfs_extattrctl)(MP, C, FN, NS, N); \ 803 _rc; }) 804 805 #define VFS_SYSCTL(MP, OP, REQ) ({ \ 806 int _rc; \ 807 \ 808 _rc = (*(MP)->mnt_op->vfs_sysctl)(MP, OP, REQ); \ 809 _rc; }) 810 811 #define VFS_SUSP_CLEAN(MP) do { \ 812 if (*(MP)->mnt_op->vfs_susp_clean != NULL) { \ 813 (*(MP)->mnt_op->vfs_susp_clean)(MP); \ 814 } \ 815 } while (0) 816 817 #define VFS_RECLAIM_LOWERVP(MP, VP) do { \ 818 if (*(MP)->mnt_op->vfs_reclaim_lowervp != NULL) { \ 819 (*(MP)->mnt_op->vfs_reclaim_lowervp)((MP), (VP)); \ 820 } \ 821 } while (0) 822 823 #define VFS_UNLINK_LOWERVP(MP, VP) do { \ 824 if (*(MP)->mnt_op->vfs_unlink_lowervp != NULL) { \ 825 (*(MP)->mnt_op->vfs_unlink_lowervp)((MP), (VP)); \ 826 } \ 827 } while (0) 828 829 #define VFS_PURGE(MP) do { \ 830 if (*(MP)->mnt_op->vfs_purge != NULL) { \ 831 (*(MP)->mnt_op->vfs_purge)(MP); \ 832 } \ 833 } while (0) 834 835 #define VFS_KNOTE_LOCKED(vp, hint) do \ 836 { \ 837 if (((vp)->v_vflag & VV_NOKNOTE) == 0) \ 838 VN_KNOTE((vp), (hint), KNF_LISTLOCKED); \ 839 } while (0) 840 841 #define VFS_KNOTE_UNLOCKED(vp, hint) do \ 842 { \ 843 if (((vp)->v_vflag & VV_NOKNOTE) == 0) \ 844 VN_KNOTE((vp), (hint), 0); \ 845 } while (0) 846 847 #define VFS_NOTIFY_UPPER_RECLAIM 1 848 #define VFS_NOTIFY_UPPER_UNLINK 2 849 850 #include <sys/module.h> 851 852 /* 853 * Version numbers. 854 */ 855 #define VFS_VERSION_00 0x19660120 856 #define VFS_VERSION_01 0x20121030 857 #define VFS_VERSION_02 0x20180504 858 #define VFS_VERSION VFS_VERSION_02 859 860 #define VFS_SET(vfsops, fsname, flags) \ 861 static struct vfsconf fsname ## _vfsconf = { \ 862 .vfc_version = VFS_VERSION, \ 863 .vfc_name = #fsname, \ 864 .vfc_vfsops = &vfsops, \ 865 .vfc_typenum = -1, \ 866 .vfc_flags = flags, \ 867 }; \ 868 static moduledata_t fsname ## _mod = { \ 869 #fsname, \ 870 vfs_modevent, \ 871 & fsname ## _vfsconf \ 872 }; \ 873 DECLARE_MODULE(fsname, fsname ## _mod, SI_SUB_VFS, SI_ORDER_MIDDLE) 874 875 /* 876 * exported vnode operations 877 */ 878 879 int dounmount(struct mount *, int, struct thread *); 880 881 int kernel_mount(struct mntarg *ma, uint64_t flags); 882 int kernel_vmount(int flags, ...); 883 struct mntarg *mount_arg(struct mntarg *ma, const char *name, const void *val, int len); 884 struct mntarg *mount_argb(struct mntarg *ma, int flag, const char *name); 885 struct mntarg *mount_argf(struct mntarg *ma, const char *name, const char *fmt, ...); 886 struct mntarg *mount_argsu(struct mntarg *ma, const char *name, const void *val, int len); 887 void statfs_scale_blocks(struct statfs *sf, long max_size); 888 struct vfsconf *vfs_byname(const char *); 889 struct vfsconf *vfs_byname_kld(const char *, struct thread *td, int *); 890 void vfs_mount_destroy(struct mount *); 891 void vfs_event_signal(fsid_t *, u_int32_t, intptr_t); 892 void vfs_freeopts(struct vfsoptlist *opts); 893 void vfs_deleteopt(struct vfsoptlist *opts, const char *name); 894 int vfs_buildopts(struct uio *auio, struct vfsoptlist **options); 895 int vfs_flagopt(struct vfsoptlist *opts, const char *name, uint64_t *w, 896 uint64_t val); 897 int vfs_getopt(struct vfsoptlist *, const char *, void **, int *); 898 int vfs_getopt_pos(struct vfsoptlist *opts, const char *name); 899 int vfs_getopt_size(struct vfsoptlist *opts, const char *name, 900 off_t *value); 901 char *vfs_getopts(struct vfsoptlist *, const char *, int *error); 902 int vfs_copyopt(struct vfsoptlist *, const char *, void *, int); 903 int vfs_filteropt(struct vfsoptlist *, const char **legal); 904 void vfs_opterror(struct vfsoptlist *opts, const char *fmt, ...); 905 int vfs_scanopt(struct vfsoptlist *opts, const char *name, const char *fmt, ...); 906 int vfs_setopt(struct vfsoptlist *opts, const char *name, void *value, 907 int len); 908 int vfs_setopt_part(struct vfsoptlist *opts, const char *name, void *value, 909 int len); 910 int vfs_setopts(struct vfsoptlist *opts, const char *name, 911 const char *value); 912 int vfs_setpublicfs /* set publicly exported fs */ 913 (struct mount *, struct netexport *, struct export_args *); 914 void vfs_periodic(struct mount *, int); 915 int vfs_busy(struct mount *, int); 916 int vfs_export /* process mount export info */ 917 (struct mount *, struct export_args *); 918 void vfs_allocate_syncvnode(struct mount *); 919 void vfs_deallocate_syncvnode(struct mount *); 920 int vfs_donmount(struct thread *td, uint64_t fsflags, 921 struct uio *fsoptions); 922 void vfs_getnewfsid(struct mount *); 923 struct cdev *vfs_getrootfsid(struct mount *); 924 struct mount *vfs_getvfs(fsid_t *); /* return vfs given fsid */ 925 struct mount *vfs_busyfs(fsid_t *); 926 int vfs_modevent(module_t, int, void *); 927 void vfs_mount_error(struct mount *, const char *, ...); 928 void vfs_mountroot(void); /* mount our root filesystem */ 929 void vfs_mountedfrom(struct mount *, const char *from); 930 void vfs_notify_upper(struct vnode *, int); 931 void vfs_oexport_conv(const struct oexport_args *oexp, 932 struct export_args *exp); 933 void vfs_ref(struct mount *); 934 void vfs_rel(struct mount *); 935 struct mount *vfs_mount_alloc(struct vnode *, struct vfsconf *, const char *, 936 struct ucred *); 937 int vfs_suser(struct mount *, struct thread *); 938 void vfs_unbusy(struct mount *); 939 void vfs_unmountall(void); 940 extern TAILQ_HEAD(mntlist, mount) mountlist; /* mounted filesystem list */ 941 extern struct mtx mountlist_mtx; 942 extern struct nfs_public nfs_pub; 943 extern struct sx vfsconf_sx; 944 #define vfsconf_lock() sx_xlock(&vfsconf_sx) 945 #define vfsconf_unlock() sx_xunlock(&vfsconf_sx) 946 #define vfsconf_slock() sx_slock(&vfsconf_sx) 947 #define vfsconf_sunlock() sx_sunlock(&vfsconf_sx) 948 struct vnode *mntfs_allocvp(struct mount *, struct vnode *); 949 void mntfs_freevp(struct vnode *); 950 951 /* 952 * Declarations for these vfs default operations are located in 953 * kern/vfs_default.c. They will be automatically used to replace 954 * null entries in VFS ops tables when registering a new filesystem 955 * type in the global table. 956 */ 957 vfs_root_t vfs_stdroot; 958 vfs_quotactl_t vfs_stdquotactl; 959 vfs_statfs_t vfs_stdstatfs; 960 vfs_sync_t vfs_stdsync; 961 vfs_sync_t vfs_stdnosync; 962 vfs_vget_t vfs_stdvget; 963 vfs_fhtovp_t vfs_stdfhtovp; 964 vfs_checkexp_t vfs_stdcheckexp; 965 vfs_init_t vfs_stdinit; 966 vfs_uninit_t vfs_stduninit; 967 vfs_extattrctl_t vfs_stdextattrctl; 968 vfs_sysctl_t vfs_stdsysctl; 969 970 void syncer_suspend(void); 971 void syncer_resume(void); 972 973 struct vnode *vfs_cache_root_clear(struct mount *); 974 void vfs_cache_root_set(struct mount *, struct vnode *); 975 976 void vfs_op_barrier_wait(struct mount *); 977 void vfs_op_enter(struct mount *); 978 void vfs_op_exit_locked(struct mount *); 979 void vfs_op_exit(struct mount *); 980 981 #ifdef DIAGNOSTIC 982 void vfs_assert_mount_counters(struct mount *); 983 void vfs_dump_mount_counters(struct mount *); 984 #else 985 #define vfs_assert_mount_counters(mp) do { } while (0) 986 #define vfs_dump_mount_counters(mp) do { } while (0) 987 #endif 988 989 enum mount_counter { MNT_COUNT_REF, MNT_COUNT_LOCKREF, MNT_COUNT_WRITEOPCOUNT }; 990 int vfs_mount_fetch_counter(struct mount *, enum mount_counter); 991 992 /* 993 * Code transitioning mnt_vfs_ops to > 0 issues IPIs until it observes 994 * all CPUs not executing code enclosed by mnt_thread_in_ops_pcpu. 995 * 996 * This provides an invariant that by the time the last CPU is observed not 997 * executing, everyone else entering will see the counter > 0 and exit. 998 * 999 * Note there is no barrier between vfs_ops and the rest of the code in the 1000 * section. It is not necessary as the writer has to wait for everyone to drain 1001 * before making any changes or only make changes safe while the section is 1002 * executed. 1003 */ 1004 #define vfs_op_thread_entered(mp) ({ \ 1005 MPASS(curthread->td_critnest > 0); \ 1006 *zpcpu_get(mp->mnt_thread_in_ops_pcpu) == 1; \ 1007 }) 1008 1009 #define vfs_op_thread_enter(mp) ({ \ 1010 bool _retval = true; \ 1011 critical_enter(); \ 1012 MPASS(!vfs_op_thread_entered(mp)); \ 1013 zpcpu_set_protected(mp->mnt_thread_in_ops_pcpu, 1); \ 1014 __compiler_membar(); \ 1015 if (__predict_false(mp->mnt_vfs_ops > 0)) { \ 1016 vfs_op_thread_exit(mp); \ 1017 _retval = false; \ 1018 } \ 1019 _retval; \ 1020 }) 1021 1022 #define vfs_op_thread_exit(mp) do { \ 1023 MPASS(vfs_op_thread_entered(mp)); \ 1024 __compiler_membar(); \ 1025 zpcpu_set_protected(mp->mnt_thread_in_ops_pcpu, 0); \ 1026 critical_exit(); \ 1027 } while (0) 1028 1029 #define vfs_mp_count_add_pcpu(mp, count, val) do { \ 1030 MPASS(vfs_op_thread_entered(mp)); \ 1031 zpcpu_add_protected(mp->mnt_##count##_pcpu, val); \ 1032 } while (0) 1033 1034 #define vfs_mp_count_sub_pcpu(mp, count, val) do { \ 1035 MPASS(vfs_op_thread_entered(mp)); \ 1036 zpcpu_sub_protected(mp->mnt_##count##_pcpu, val); \ 1037 } while (0) 1038 1039 #else /* !_KERNEL */ 1040 1041 #include <sys/cdefs.h> 1042 1043 struct stat; 1044 1045 __BEGIN_DECLS 1046 int fhlink(struct fhandle *, const char *); 1047 int fhlinkat(struct fhandle *, int, const char *); 1048 int fhopen(const struct fhandle *, int); 1049 int fhreadlink(struct fhandle *, char *, size_t); 1050 int fhstat(const struct fhandle *, struct stat *); 1051 int fhstatfs(const struct fhandle *, struct statfs *); 1052 int fstatfs(int, struct statfs *); 1053 int getfh(const char *, fhandle_t *); 1054 int getfhat(int, char *, struct fhandle *, int); 1055 int getfsstat(struct statfs *, long, int); 1056 int getmntinfo(struct statfs **, int); 1057 int lgetfh(const char *, fhandle_t *); 1058 int mount(const char *, const char *, int, void *); 1059 int nmount(struct iovec *, unsigned int, int); 1060 int statfs(const char *, struct statfs *); 1061 int unmount(const char *, int); 1062 1063 /* C library stuff */ 1064 int getvfsbyname(const char *, struct xvfsconf *); 1065 __END_DECLS 1066 1067 #endif /* _KERNEL */ 1068 1069 #endif /* !_SYS_MOUNT_H_ */ 1070