1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 
  22 /*
  23  * Copyright (c) 1988, 2010, Oracle and/or its affiliates. All rights reserved.
  24  * Copyright 2016 Toomas Soome <tsoome@me.com>
  25  * Copyright (c) 2016 by Delphix. All rights reserved.
  26  * Copyright 2016 Nexenta Systems, Inc.
  27  */
  28 
  29 /*      Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */
  30 /*        All Rights Reserved   */
  31 
  32 /*
  33  * Portions of this source code were derived from Berkeley 4.3 BSD
  34  * under license from the Regents of the University of California.
  35  */
  36 
  37 #ifndef _SYS_VFS_H
  38 #define _SYS_VFS_H
  39 
  40 #include <sys/zone.h>
  41 #include <sys/types.h>
  42 #include <sys/t_lock.h>
  43 #include <sys/cred.h>
  44 #include <sys/vnode.h>
  45 #include <sys/statvfs.h>
  46 #include <sys/refstr.h>
  47 #include <sys/avl.h>
  48 #include <sys/time.h>
  49 
  50 #ifdef  __cplusplus
  51 extern "C" {
  52 #endif
  53 
  54 /*
  55  * Data associated with mounted file systems.
  56  */
  57 
  58 /*
  59  * Operations vector.  This is used internal to the kernel; file systems
  60  * supply their list of operations via vfs_setfsops().
  61  */
  62 
  63 typedef struct vfsops vfsops_t;
  64 
  65 /*
  66  * File system identifier. Should be unique (at least per machine).
  67  */
  68 typedef struct {
  69         int val[2];                     /* file system id type */
  70 } fsid_t;
  71 
  72 /*
  73  * File identifier.  Should be unique per filesystem on a single
  74  * machine.  This is typically called by a stateless file server
  75  * in order to generate "file handles".
  76  *
  77  * Many underlying file systems cast a struct fid into other
  78  * file system dependent structures which may require 4 byte alignment.
  79  * Because a fid starts with a short it may not be 4 byte aligned, the
  80  * fid_pad will force the alignment.
  81  */
  82 #define MAXFIDSZ        64
  83 #define OLD_MAXFIDSZ    16
  84 
  85 typedef struct fid {
  86         union {
  87                 long fid_pad;
  88                 struct {
  89                         ushort_t len;   /* length of data in bytes */
  90                         char    data[MAXFIDSZ]; /* data (variable len) */
  91                 } _fid;
  92         } un;
  93 } fid_t;
  94 
  95 #ifdef _SYSCALL32
  96 /*
  97  * Solaris 64 - use old-style cache format with 32-bit aligned fid for on-disk
  98  * struct compatibility.
  99  */
 100 typedef struct fid32 {
 101         union {
 102                 int32_t fid_pad;
 103                 struct {
 104                         uint16_t  len;   /* length of data in bytes */
 105                         char    data[MAXFIDSZ]; /* data (variable len) */
 106                 } _fid;
 107         } un;
 108 } fid32_t;
 109 #else /* not _SYSCALL32 */
 110 #define fid32   fid
 111 typedef fid_t   fid32_t;
 112 #endif /* _SYSCALL32 */
 113 
 114 #define fid_len         un._fid.len
 115 #define fid_data        un._fid.data
 116 
 117 /*
 118  * Structure defining a mount option for a filesystem.
 119  * option names are found in mntent.h
 120  */
 121 typedef struct mntopt {
 122         char    *mo_name;       /* option name */
 123         char    **mo_cancel;    /* list of options cancelled by this one */
 124         char    *mo_arg;        /* argument string for this option */
 125         int     mo_flags;       /* flags for this mount option */
 126         void    *mo_data;       /* filesystem specific data */
 127 } mntopt_t;
 128 
 129 /*
 130  * Flags that apply to mount options
 131  */
 132 
 133 #define MO_SET          0x01            /* option is set */
 134 #define MO_NODISPLAY    0x02            /* option not listed in mnttab */
 135 #define MO_HASVALUE     0x04            /* option takes a value */
 136 #define MO_IGNORE       0x08            /* option ignored by parser */
 137 #define MO_DEFAULT      MO_SET          /* option is on by default */
 138 #define MO_TAG          0x10            /* flags a tag set by user program */
 139 #define MO_EMPTY        0x20            /* empty space in option table */
 140 
 141 #define VFS_NOFORCEOPT  0x01            /* honor MO_IGNORE (don't set option) */
 142 #define VFS_DISPLAY     0x02            /* Turn off MO_NODISPLAY bit for opt */
 143 #define VFS_NODISPLAY   0x04            /* Turn on MO_NODISPLAY bit for opt */
 144 #define VFS_CREATEOPT   0x08            /* Create the opt if it's not there */
 145 
 146 /*
 147  * Structure holding mount option strings for the mounted file system.
 148  */
 149 typedef struct mntopts {
 150         uint_t          mo_count;               /* number of entries in table */
 151         mntopt_t        *mo_list;               /* list of mount options */
 152 } mntopts_t;
 153 
 154 /*
 155  * The kstat structures associated with the vopstats are kept in an
 156  * AVL tree.  This is to avoid the case where a file system does not
 157  * use a unique fsid_t for each vfs (e.g., namefs).  In order to do
 158  * this, we need a structure that the AVL tree can use that also
 159  * references the kstat.
 160  * Note that the vks_fsid is generated from the value reported by
 161  * VFS_STATVFS().
 162  */
 163 typedef struct vskstat_anchor {
 164         avl_node_t      vsk_node;       /* Required for use by AVL routines */
 165         kstat_t         *vsk_ksp;       /* kstat structure for vopstats */
 166         ulong_t         vsk_fsid;       /* fsid associated w/this FS */
 167 } vsk_anchor_t;
 168 
 169 extern avl_tree_t       vskstat_tree;
 170 extern kmutex_t         vskstat_tree_lock;
 171 
 172 /*
 173  * Structure per mounted file system.  Each mounted file system has
 174  * an array of operations and an instance record.
 175  *
 176  * The file systems are kept on a doubly linked circular list headed by
 177  * "rootvfs".
 178  * File system implementations should not access this list;
 179  * it's intended for use only in the kernel's vfs layer.
 180  *
 181  * Each zone also has its own list of mounts, containing filesystems mounted
 182  * somewhere within the filesystem tree rooted at the zone's rootpath.  The
 183  * list is doubly linked to match the global list.
 184  *
 185  * mnttab locking: the in-kernel mnttab uses the vfs_mntpt, vfs_resource and
 186  * vfs_mntopts fields in the vfs_t. mntpt and resource are refstr_ts that
 187  * are set at mount time and can only be modified during a remount.
 188  * It is safe to read these fields if you can prevent a remount on the vfs,
 189  * or through the convenience funcs vfs_getmntpoint() and vfs_getresource().
 190  * The mntopts field may only be accessed through the provided convenience
 191  * functions, as it is protected by the vfs list lock. Modifying a mount
 192  * option requires grabbing the vfs list write lock, which can be a very
 193  * high latency lock.
 194  */
 195 struct zone;            /* from zone.h */
 196 struct fem_head;        /* from fem.h */
 197 
 198 typedef struct vfs {
 199         struct vfs      *vfs_next;              /* next VFS in VFS list */
 200         struct vfs      *vfs_prev;              /* prev VFS in VFS list */
 201 
 202 /* vfs_op should not be used directly.  Accessor functions are provided */
 203         vfsops_t        *vfs_op;                /* operations on VFS */
 204 
 205         struct vnode    *vfs_vnodecovered;      /* vnode mounted on */
 206         uint_t          vfs_flag;               /* flags */
 207         uint_t          vfs_bsize;              /* native block size */
 208         int             vfs_fstype;             /* file system type index */
 209         fsid_t          vfs_fsid;               /* file system id */
 210         void            *vfs_data;              /* private data */
 211         dev_t           vfs_dev;                /* device of mounted VFS */
 212         ulong_t         vfs_bcount;             /* I/O count (accounting) */
 213         struct vfs      *vfs_list;              /* sync list pointer */
 214         struct vfs      *vfs_hash;              /* hash list pointer */
 215         ksema_t         vfs_reflock;            /* mount/unmount/sync lock */
 216         uint_t          vfs_count;              /* vfs reference count */
 217         mntopts_t       vfs_mntopts;            /* options mounted with */
 218         refstr_t        *vfs_resource;          /* mounted resource name */
 219         refstr_t        *vfs_mntpt;             /* mount point name */
 220         time_t          vfs_mtime;              /* time we were mounted */
 221         struct vfs_impl *vfs_implp;             /* impl specific data */
 222         /*
 223          * Zones support.  Note that the zone that "owns" the mount isn't
 224          * necessarily the same as the zone in which the zone is visible.
 225          * That is, vfs_zone and (vfs_zone_next|vfs_zone_prev) may refer to
 226          * different zones.
 227          */
 228         struct zone     *vfs_zone;              /* zone that owns the mount */
 229         struct vfs      *vfs_zone_next;         /* next VFS visible in zone */
 230         struct vfs      *vfs_zone_prev;         /* prev VFS visible in zone */
 231 
 232         struct fem_head *vfs_femhead;           /* fs monitoring */
 233         uint32_t        vfs_lofi_id;            /* ID if lofi mount */
 234 } vfs_t;
 235 
 236 #define vfs_featureset  vfs_implp->vi_featureset
 237 #define vfs_vskap       vfs_implp->vi_vskap
 238 #define vfs_fstypevsp   vfs_implp->vi_fstypevsp
 239 #define vfs_vopstats    vfs_implp->vi_vopstats
 240 #define vfs_hrctime     vfs_implp->vi_hrctime
 241 
 242 /*
 243  * VFS flags.
 244  */
 245 #define VFS_RDONLY      0x01            /* read-only vfs */
 246 #define VFS_NOMNTTAB    0x02            /* vfs not seen in mnttab */
 247 #define VFS_NOSETUID    0x08            /* setuid disallowed */
 248 #define VFS_REMOUNT     0x10            /* modify mount options only */
 249 #define VFS_NOTRUNC     0x20            /* does not truncate long file names */
 250 #define VFS_UNLINKABLE  0x40            /* unlink(2) can be applied to root */
 251 #define VFS_PXFS        0x80            /* clustering: global fs proxy vfs */
 252 #define VFS_UNMOUNTED   0x100           /* file system has been unmounted */
 253 #define VFS_NBMAND      0x200           /* allow non-blocking mandatory locks */
 254 #define VFS_XATTR       0x400           /* fs supports extended attributes */
 255 #define VFS_NODEVICES   0x800           /* device-special files disallowed */
 256 #define VFS_NOEXEC      0x1000          /* executables disallowed */
 257 #define VFS_STATS       0x2000          /* file system can collect stats */
 258 #define VFS_XID         0x4000          /* file system supports extended ids */
 259 
 260 #define VFS_NORESOURCE  "unspecified_resource"
 261 #define VFS_NOMNTPT     "unspecified_mountpoint"
 262 
 263 /*
 264  * VFS features are implemented as bits set in the vfs_t.
 265  * The vfs_feature_t typedef is a 64-bit number that will translate
 266  * into an element in an array of bitmaps and a bit in that element.
 267  * Developers must not depend on the implementation of this and
 268  * need to use vfs_has_feature()/vfs_set_feature() routines.
 269  */
 270 typedef uint64_t        vfs_feature_t;
 271 
 272 #define VFSFT_XVATTR            0x100000001     /* Supports xvattr for attrs */
 273 #define VFSFT_CASEINSENSITIVE   0x100000002     /* Supports case-insensitive */
 274 #define VFSFT_NOCASESENSITIVE   0x100000004     /* NOT case-sensitive */
 275 #define VFSFT_DIRENTFLAGS       0x100000008     /* Supports dirent flags */
 276 #define VFSFT_ACLONCREATE       0x100000010     /* Supports ACL on create */
 277 #define VFSFT_ACEMASKONACCESS   0x100000020     /* Can use ACEMASK for access */
 278 #define VFSFT_SYSATTR_VIEWS     0x100000040     /* Supports sysattr view i/f */
 279 #define VFSFT_ACCESS_FILTER     0x100000080     /* dirents filtered by access */
 280 #define VFSFT_REPARSE           0x100000100     /* Supports reparse point */
 281 #define VFSFT_ZEROCOPY_SUPPORTED        0x100000200
 282                                 /* Support loaning /returning cache buffer */
 283 /*
 284  * Argument structure for mount(2).
 285  *
 286  * Flags are defined in <sys/mount.h>.
 287  *
 288  * Note that if the MS_SYSSPACE bit is set in flags, the pointer fields in
 289  * this structure are to be interpreted as kernel addresses.  File systems
 290  * should be prepared for this possibility.
 291  */
 292 struct mounta {
 293         char    *spec;
 294         char    *dir;
 295         int     flags;
 296         char    *fstype;
 297         char    *dataptr;
 298         int     datalen;
 299         char    *optptr;
 300         int     optlen;
 301 };
 302 
 303 /*
 304  * Reasons for calling the vfs_mountroot() operation.
 305  */
 306 enum whymountroot { ROOT_INIT, ROOT_REMOUNT, ROOT_UNMOUNT};
 307 typedef enum whymountroot whymountroot_t;
 308 
 309 /*
 310  * Reasons for calling the VFS_VNSTATE():
 311  */
 312 enum vntrans {
 313         VNTRANS_EXISTS,
 314         VNTRANS_IDLED,
 315         VNTRANS_RECLAIMED,
 316         VNTRANS_DESTROYED
 317 };
 318 typedef enum vntrans vntrans_t;
 319 
 320 /*
 321  * VFS_OPS defines all the vfs operations.  It is used to define
 322  * the vfsops structure (below) and the fs_func_p union (vfs_opreg.h).
 323  */
 324 #define VFS_OPS                                                         \
 325         int     (*vfs_mount)(vfs_t *, vnode_t *, struct mounta *, cred_t *); \
 326         int     (*vfs_unmount)(vfs_t *, int, cred_t *);                 \
 327         int     (*vfs_root)(vfs_t *, vnode_t **);                       \
 328         int     (*vfs_statvfs)(vfs_t *, statvfs64_t *);                 \
 329         int     (*vfs_sync)(vfs_t *, short, cred_t *);                  \
 330         int     (*vfs_vget)(vfs_t *, vnode_t **, fid_t *);              \
 331         int     (*vfs_mountroot)(vfs_t *, enum whymountroot);           \
 332         void    (*vfs_freevfs)(vfs_t *);                                \
 333         int     (*vfs_vnstate)(vfs_t *, vnode_t *, vntrans_t)   /* NB: No ";" */
 334 
 335 /*
 336  * Operations supported on virtual file system.
 337  */
 338 struct vfsops {
 339         VFS_OPS;        /* Signature of all vfs operations (vfsops) */
 340 };
 341 
 342 extern int      fsop_mount(vfs_t *, vnode_t *, struct mounta *, cred_t *);
 343 extern int      fsop_unmount(vfs_t *, int, cred_t *);
 344 extern int      fsop_root(vfs_t *, vnode_t **);
 345 extern int      fsop_statfs(vfs_t *, statvfs64_t *);
 346 extern int      fsop_sync(vfs_t *, short, cred_t *);
 347 extern int      fsop_vget(vfs_t *, vnode_t **, fid_t *);
 348 extern int      fsop_mountroot(vfs_t *, enum whymountroot);
 349 extern void     fsop_freefs(vfs_t *);
 350 extern int      fsop_sync_by_kind(int, short, cred_t *);
 351 extern int      fsop_vnstate(vfs_t *, vnode_t *, vntrans_t);
 352 
 353 #define VFS_MOUNT(vfsp, mvp, uap, cr) fsop_mount(vfsp, mvp, uap, cr)
 354 #define VFS_UNMOUNT(vfsp, flag, cr) fsop_unmount(vfsp, flag, cr)
 355 #define VFS_ROOT(vfsp, vpp) fsop_root(vfsp, vpp)
 356 #define VFS_STATVFS(vfsp, sp) fsop_statfs(vfsp, sp)
 357 #define VFS_SYNC(vfsp, flag, cr) fsop_sync(vfsp, flag, cr)
 358 #define VFS_VGET(vfsp, vpp, fidp) fsop_vget(vfsp, vpp, fidp)
 359 #define VFS_MOUNTROOT(vfsp, init) fsop_mountroot(vfsp, init)
 360 #define VFS_FREEVFS(vfsp) fsop_freefs(vfsp)
 361 #define VFS_VNSTATE(vfsp, vn, ns)       fsop_vnstate(vfsp, vn, ns)
 362 
 363 #define VFSNAME_MOUNT           "mount"
 364 #define VFSNAME_UNMOUNT         "unmount"
 365 #define VFSNAME_ROOT            "root"
 366 #define VFSNAME_STATVFS         "statvfs"
 367 #define VFSNAME_SYNC            "sync"
 368 #define VFSNAME_VGET            "vget"
 369 #define VFSNAME_MOUNTROOT       "mountroot"
 370 #define VFSNAME_FREEVFS         "freevfs"
 371 #define VFSNAME_VNSTATE         "vnstate"
 372 /*
 373  * Filesystem type switch table.
 374  */
 375 
 376 typedef struct vfssw {
 377         char            *vsw_name;      /* type name -- max len _ST_FSTYPSZ */
 378         int             (*vsw_init) (int, char *);
 379                                 /* init routine (for non-loadable fs only) */
 380         int             vsw_flag;       /* flags */
 381         mntopts_t       vsw_optproto;   /* mount options table prototype */
 382         uint_t          vsw_count;      /* count of references */
 383         kmutex_t        vsw_lock;       /* lock to protect vsw_count */
 384         vfsops_t        vsw_vfsops;     /* filesystem operations vector */
 385 } vfssw_t;
 386 
 387 /*
 388  * Filesystem type definition record.  All file systems must export a record
 389  * of this type through their modlfs structure.  N.B., changing the version
 390  * number requires a change in sys/modctl.h.
 391  */
 392 
 393 typedef struct vfsdef_v5 {
 394         int             def_version;    /* structure version, must be first */
 395         char            *name;          /* filesystem type name */
 396         int             (*init) (int, char *);  /* init routine */
 397         int             flags;          /* filesystem flags */
 398         mntopts_t       *optproto;      /* mount options table prototype */
 399 } vfsdef_v5;
 400 
 401 typedef struct vfsdef_v5 vfsdef_t;
 402 
 403 enum {
 404         VFSDEF_VERSION = 5
 405 };
 406 
 407 /*
 408  * flags for vfssw and vfsdef
 409  */
 410 #define VSW_HASPROTO    0x01    /* struct has a mount options prototype */
 411 #define VSW_CANRWRO     0x02    /* file system can transition from rw to ro */
 412 #define VSW_CANREMOUNT  0x04    /* file system supports remounts */
 413 #define VSW_NOTZONESAFE 0x08    /* zone_enter(2) should fail for these files */
 414 #define VSW_VOLATILEDEV 0x10    /* vfs_dev can change each time fs is mounted */
 415 #define VSW_STATS       0x20    /* file system can collect stats */
 416 #define VSW_XID         0x40    /* file system supports extended ids */
 417 #define VSW_CANLOFI     0x80    /* file system supports lofi mounts */
 418 #define VSW_ZMOUNT      0x100   /* file system always allowed in a zone */
 419 
 420 #define VSW_INSTALLED   0x8000  /* this vsw is associated with a file system */
 421 
 422 /*
 423  * A flag for vfs_setpath().
 424  */
 425 #define VFSSP_VERBATIM  0x1     /* do not prefix the supplied path */
 426 
 427 #if defined(_KERNEL) || defined(_FAKE_KERNEL)
 428 
 429 /*
 430  * Private vfs data, NOT to be used by a file system implementation.
 431  */
 432 
 433 #define VFS_FEATURE_MAXSZ       4
 434 
 435 typedef struct vfs_impl {
 436         /* Counted array - Bitmap of vfs features */
 437         uint32_t        vi_featureset[VFS_FEATURE_MAXSZ];
 438         /*
 439          * Support for statistics on the vnode operations
 440          */
 441         vsk_anchor_t    *vi_vskap;              /* anchor for vopstats' kstat */
 442         vopstats_t      *vi_fstypevsp;          /* ptr to per-fstype vopstats */
 443         vopstats_t      vi_vopstats;            /* per-mount vnode op stats */
 444 
 445         timespec_t      vi_hrctime;             /* High-res creation time */
 446 
 447         zone_ref_t      vi_zone_ref;            /* reference to zone */
 448 } vfs_impl_t;
 449 
 450 /*
 451  * Public operations.
 452  */
 453 struct umounta;
 454 struct statvfsa;
 455 struct fstatvfsa;
 456 
 457 void    vfs_freevfsops(vfsops_t *);
 458 int     vfs_freevfsops_by_type(int);
 459 void    vfs_setops(vfs_t *, vfsops_t *);
 460 vfsops_t *vfs_getops(vfs_t *vfsp);
 461 int     vfs_matchops(vfs_t *, vfsops_t *);
 462 int     vfs_can_sync(vfs_t *vfsp);
 463 vfs_t   *vfs_alloc(int);
 464 void    vfs_free(vfs_t *);
 465 void    vfs_init(vfs_t *vfsp, vfsops_t *, void *);
 466 void    vfsimpl_setup(vfs_t *vfsp);
 467 void    vfsimpl_teardown(vfs_t *vfsp);
 468 void    vn_exists(vnode_t *);
 469 void    vn_idle(vnode_t *);
 470 void    vn_reclaim(vnode_t *);
 471 void    vn_invalid(vnode_t *);
 472 
 473 int     rootconf(void);
 474 int     domount(char *, struct mounta *, vnode_t *, struct cred *,
 475             struct vfs **);
 476 int     dounmount(struct vfs *, int, cred_t *);
 477 int     vfs_lock(struct vfs *);
 478 int     vfs_rlock(struct vfs *);
 479 void    vfs_lock_wait(struct vfs *);
 480 void    vfs_rlock_wait(struct vfs *);
 481 void    vfs_unlock(struct vfs *);
 482 int     vfs_lock_held(struct vfs *);
 483 struct  _kthread *vfs_lock_owner(struct vfs *);
 484 void    sync(void);
 485 void    vfs_sync(int);
 486 void    vfs_mountroot(void);
 487 void    vfs_add(vnode_t *, struct vfs *, int);
 488 void    vfs_remove(struct vfs *);
 489 
 490 /* VFS feature routines */
 491 void    vfs_set_feature(vfs_t *, vfs_feature_t);
 492 void    vfs_clear_feature(vfs_t *, vfs_feature_t);
 493 int     vfs_has_feature(vfs_t *, vfs_feature_t);
 494 void    vfs_propagate_features(vfs_t *, vfs_t *);
 495 
 496 /* The following functions are not for general use by filesystems */
 497 
 498 void    vfs_createopttbl(mntopts_t *, const char *);
 499 void    vfs_copyopttbl(const mntopts_t *, mntopts_t *);
 500 void    vfs_mergeopttbl(const mntopts_t *, const mntopts_t *, mntopts_t *);
 501 void    vfs_freeopttbl(mntopts_t *);
 502 void    vfs_parsemntopts(mntopts_t *, char *, int);
 503 int     vfs_buildoptionstr(const mntopts_t *, char *, int);
 504 struct mntopt *vfs_hasopt(const mntopts_t *, const char *);
 505 void    vfs_mnttab_modtimeupd(void);
 506 
 507 void    vfs_clearmntopt(struct vfs *, const char *);
 508 void    vfs_setmntopt(struct vfs *, const char *, const char *, int);
 509 void    vfs_setresource(struct vfs *, const char *, uint32_t);
 510 void    vfs_setmntpoint(struct vfs *, const char *, uint32_t);
 511 refstr_t *vfs_getresource(const struct vfs *);
 512 refstr_t *vfs_getmntpoint(const struct vfs *);
 513 int     vfs_optionisset(const struct vfs *, const char *, char **);
 514 int     vfs_settag(uint_t, uint_t, const char *, const char *, cred_t *);
 515 int     vfs_clrtag(uint_t, uint_t, const char *, const char *, cred_t *);
 516 void    vfs_syncall(void);
 517 void    vfsinit(void);
 518 void    vfs_unmountall(void);
 519 void    vfs_make_fsid(fsid_t *, dev_t, int);
 520 void    vfs_addmip(dev_t, struct vfs *);
 521 void    vfs_delmip(struct vfs *);
 522 int     vfs_devismounted(dev_t);
 523 int     vfs_devmounting(dev_t, struct vfs *);
 524 int     vfs_opsinuse(vfsops_t *);
 525 struct vfs *getvfs(fsid_t *);
 526 struct vfs *vfs_dev2vfsp(dev_t);
 527 struct vfs *vfs_mntpoint2vfsp(const char *);
 528 struct vfssw *allocate_vfssw(const char *);
 529 struct vfssw *vfs_getvfssw(const char *);
 530 struct vfssw *vfs_getvfsswbyname(const char *);
 531 struct vfssw *vfs_getvfsswbyvfsops(vfsops_t *);
 532 void    vfs_refvfssw(struct vfssw *);
 533 void    vfs_unrefvfssw(struct vfssw *);
 534 uint_t  vf_to_stf(uint_t);
 535 void    vfs_mnttab_modtime(timespec_t *);
 536 void    vfs_mnttab_poll(timespec_t *, struct pollhead **);
 537 
 538 void    vfs_list_lock(void);
 539 void    vfs_list_read_lock(void);
 540 void    vfs_list_unlock(void);
 541 void    vfs_list_add(struct vfs *);
 542 void    vfs_list_remove(struct vfs *);
 543 void    vfs_hold(vfs_t *vfsp);
 544 void    vfs_rele(vfs_t *vfsp);
 545 void    fs_freevfs(vfs_t *);
 546 void    vfs_root_redev(vfs_t *vfsp, dev_t ndev, int fstype);
 547 
 548 int     vfs_zone_change_safe(vfs_t *);
 549 
 550 int     vfs_get_lofi(vfs_t *, vnode_t **);
 551 
 552 #define VFSHASH(maj, min) (((int)((maj)+(min))) & (vfshsz - 1))
 553 #define VFS_ON_LIST(vfsp) \
 554         ((vfsp)->vfs_next != (vfsp) && (vfsp)->vfs_next != NULL)
 555 
 556 /*
 557  * Globals.
 558  */
 559 
 560 extern struct vfssw vfssw[];            /* table of filesystem types */
 561 extern krwlock_t vfssw_lock;
 562 extern char rootfstype[];               /* name of root fstype */
 563 extern const int nfstype;               /* # of elements in vfssw array */
 564 extern vfsops_t *EIO_vfsops;            /* operations for vfs being torn-down */
 565 
 566 /*
 567  * The following variables are private to the the kernel's vfs layer.  File
 568  * system implementations should not access them.
 569  */
 570 extern struct vfs *rootvfs;             /* ptr to root vfs structure */
 571 typedef struct {
 572         struct vfs *rvfs_head;          /* head vfs in chain */
 573         kmutex_t rvfs_lock;             /* mutex protecting this chain */
 574         uint32_t rvfs_len;              /* length of this chain */
 575 } rvfs_t;
 576 extern rvfs_t *rvfs_list;
 577 extern int vfshsz;                      /* # of elements in rvfs_head array */
 578 extern const mntopts_t vfs_mntopts;     /* globally recognized options */
 579 
 580 #endif /* defined(_KERNEL) */
 581 
 582 #define VFS_HOLD(vfsp) { \
 583         vfs_hold(vfsp); \
 584 }
 585 
 586 #define VFS_RELE(vfsp)  { \
 587         vfs_rele(vfsp); \
 588 }
 589 
 590 #define VFS_INIT(vfsp, op, data) { \
 591         vfs_init((vfsp), (op), (data)); \
 592 }
 593 
 594 
 595 #define VFS_INSTALLED(vfsswp)   (((vfsswp)->vsw_flag & VSW_INSTALLED) != 0)
 596 #define ALLOCATED_VFSSW(vswp)           ((vswp)->vsw_name[0] != '\0')
 597 #define RLOCK_VFSSW()                   (rw_enter(&vfssw_lock, RW_READER))
 598 #define RUNLOCK_VFSSW()                 (rw_exit(&vfssw_lock))
 599 #define WLOCK_VFSSW()                   (rw_enter(&vfssw_lock, RW_WRITER))
 600 #define WUNLOCK_VFSSW()                 (rw_exit(&vfssw_lock))
 601 #define VFSSW_LOCKED()                  (RW_LOCK_HELD(&vfssw_lock))
 602 #define VFSSW_WRITE_LOCKED()            (RW_WRITE_HELD(&vfssw_lock))
 603 /*
 604  * VFS_SYNC flags.
 605  */
 606 #define SYNC_ATTR       0x01            /* sync attributes only */
 607 #define SYNC_CLOSE      0x02            /* close open file */
 608 #define SYNC_ALL        0x04            /* force to sync all fs */
 609 
 610 #ifdef  __cplusplus
 611 }
 612 #endif
 613 
 614 #endif  /* _SYS_VFS_H */