/*      $OpenBSD: mount.h,v 1.153 2025/01/02 01:19:22 dlg Exp $ */
/*      $NetBSD: mount.h,v 1.48 1996/02/18 11:55:47 fvdl Exp $  */

/*
 * Copyright (c) 1989, 1991, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *      @(#)mount.h     8.15 (Berkeley) 7/14/94
 */

#ifndef _SYS_MOUNT_H_
#define _SYS_MOUNT_H_

#include <sys/cdefs.h>
#ifndef _KERNEL
#include <sys/ucred.h>
#endif
#include <sys/queue.h>
#include <sys/rwlock.h>

typedef struct { int32_t val[2]; } fsid_t;      /* file system id type */

/*
 * File identifier.
 * These are unique per filesystem on a single machine.
 */
#define MAXFIDSZ        16

struct fid {
        u_short         fid_len;                /* length of data in bytes */
        u_short         fid_reserved;           /* force longword alignment */
        char            fid_data[MAXFIDSZ];     /* data (variable length) */
};

/*
 * Export arguments for local filesystem mount calls.
 */
struct export_args {
        int     ex_flags;               /* export related flags */
        uid_t   ex_root;                /* mapping for root uid */
        struct  xucred ex_anon;         /* mapping for anonymous user */
        struct  sockaddr *ex_addr;      /* net address to which exported */
        int     ex_addrlen;             /* and the net address length */
        struct  sockaddr *ex_mask;      /* mask of valid bits in saddr */
        int     ex_masklen;             /* and the smask length */
};

/*
 * Arguments to mount UFS-based filesystems
 */
struct ufs_args {
        char    *fspec;                 /* block special device to mount */
        struct  export_args export_info;/* network export information */
};

/*
 * Arguments to mount MFS
 */
struct mfs_args {
        char    *fspec;                 /* name to export for statfs */
        struct  export_args export_info;/* if exported MFSes are supported */
        caddr_t base;                   /* base of file system in memory */
        u_long  size;                   /* size of file system */
};

/*
 * Arguments to mount ISO 9660 filesystems.
 */
struct iso_args {
        char    *fspec;                 /* block special device to mount */
        struct  export_args export_info;/* network export info */
        int     flags;                  /* mounting flags, see below */
        int     sess;                   /* start sector of session */
};

#define ISOFSMNT_NORRIP         0x00000001      /* disable Rock Ridge Ext.*/
#define ISOFSMNT_GENS           0x00000002      /* enable generation numbers */
#define ISOFSMNT_EXTATT         0x00000004      /* enable extended attr. */
#define ISOFSMNT_NOJOLIET       0x00000008      /* disable Joliet Ext.*/
#define ISOFSMNT_SESS           0x00000010      /* use iso_args.sess */

/*
 * Arguments to mount NFS
 */
#define NFS_ARGSVERSION 4               /* change when nfs_args changes */
struct nfs_args {
        int             version;        /* args structure version number */
        struct sockaddr *addr;          /* file server address */
        int             addrlen;        /* length of address */
        int             sotype;         /* Socket type */
        int             proto;          /* and Protocol */
        u_char          *fh;            /* File handle to be mounted */
        int             fhsize;         /* Size, in bytes, of fh */
        int             flags;          /* flags */
        int             wsize;          /* write size in bytes */
        int             rsize;          /* read size in bytes */
        int             readdirsize;    /* readdir size in bytes */
        int             timeo;          /* initial timeout in .1 secs */
        int             retrans;        /* times to retry send */
        int             maxgrouplist;   /* Max. size of group list */
        int             readahead;      /* # of blocks to readahead */
        int             leaseterm;      /* Term (sec) of lease */
        int             deadthresh;     /* Retrans threshold */
        char            *hostname;      /* server's name */
        int             acregmin;       /* Attr cache file recently modified */
        int             acregmax;       /* ac file not recently modified */
        int             acdirmin;       /* ac for dir recently modified */
        int             acdirmax;       /* ac for dir not recently modified */
};

/*
 * NFS mount option flags
 */
#define NFSMNT_RESVPORT         0x00000000  /* always use reserved ports */
#define NFSMNT_SOFT             0x00000001  /* soft mount (hard is default) */
#define NFSMNT_WSIZE            0x00000002  /* set write size */
#define NFSMNT_RSIZE            0x00000004  /* set read size */
#define NFSMNT_TIMEO            0x00000008  /* set initial timeout */
#define NFSMNT_RETRANS          0x00000010  /* set number of request retries */
#define NFSMNT_MAXGRPS          0x00000020  /* set maximum grouplist size */
#define NFSMNT_INT              0x00000040  /* allow interrupts on hard mount */
#define NFSMNT_NOCONN           0x00000080  /* Don't Connect the socket */
#define NFSMNT_NQNFS            0x00000100  /* Use Nqnfs protocol */
#define NFSMNT_NFSV3            0x00000200  /* Use NFS Version 3 protocol */
#define NFSMNT_KERB             0x00000400  /* Use Kerberos authentication */
#define NFSMNT_DUMBTIMR         0x00000800  /* Don't estimate rtt dynamically */
#define NFSMNT_LEASETERM        0x00001000  /* set lease term (nqnfs) */
#define NFSMNT_READAHEAD        0x00002000  /* set read ahead */
#define NFSMNT_DEADTHRESH       0x00004000  /* set dead server retry thresh */
#define NFSMNT_NOAC             0x00008000  /* disable attribute cache */
#define NFSMNT_RDIRPLUS         0x00010000  /* Use Readdirplus for V3 */
#define NFSMNT_READDIRSIZE      0x00020000  /* Set readdir size */

/* Flags valid only in mount syscall arguments */
#define NFSMNT_ACREGMIN         0x00040000  /* acregmin field valid */
#define NFSMNT_ACREGMAX         0x00080000  /* acregmax field valid */
#define NFSMNT_ACDIRMIN         0x00100000  /* acdirmin field valid */
#define NFSMNT_ACDIRMAX         0x00200000  /* acdirmax field valid */

/* Flags valid only in kernel */
#define NFSMNT_INTERNAL         0xfffc0000  /* Bits set internally */
#define NFSMNT_HASWRITEVERF     0x00040000  /* Has write verifier for V3 */
#define NFSMNT_GOTPATHCONF      0x00080000  /* Got the V3 pathconf info */
#define NFSMNT_GOTFSINFO        0x00100000  /* Got the V3 fsinfo */
#define NFSMNT_MNTD             0x00200000  /* Mnt server for mnt point */
#define NFSMNT_DISMINPROG       0x00400000  /* Dismount in progress */
#define NFSMNT_DISMNT           0x00800000  /* Dismounted */
#define NFSMNT_SNDLOCK          0x01000000  /* Send socket lock */
#define NFSMNT_WANTSND          0x02000000  /* Want above */
#define NFSMNT_RCVLOCK          0x04000000  /* Rcv socket lock */
#define NFSMNT_WANTRCV          0x08000000  /* Want above */
#define NFSMNT_WAITAUTH         0x10000000  /* Wait for authentication */
#define NFSMNT_HASAUTH          0x20000000  /* Has authenticator */
#define NFSMNT_WANTAUTH         0x40000000  /* Wants an authenticator */
#define NFSMNT_AUTHERR          0x80000000  /* Authentication error */

/*
 *  Arguments to mount MSDOS filesystems.
 */
struct msdosfs_args {
        char    *fspec;         /* blocks special holding the fs to mount */
        struct  export_args export_info;
                                /* network export information */
        uid_t   uid;            /* uid that owns msdosfs files */
        gid_t   gid;            /* gid that owns msdosfs files */
        mode_t  mask;           /* mask to be applied for msdosfs perms */
        int     flags;          /* see below */
};

/*
 * Msdosfs mount options:
 */
#define MSDOSFSMNT_SHORTNAME    0x01    /* Force old DOS short names only */
#define MSDOSFSMNT_LONGNAME     0x02    /* Force Win'95 long names */
#define MSDOSFSMNT_NOWIN95      0x04    /* Completely ignore Win95 entries */

/*
 * Arguments to mount ntfs filesystems
 */
struct ntfs_args {
        char    *fspec;                 /* block special device to mount */
        struct  export_args export_info;/* network export information */
        uid_t   uid;                    /* uid that owns ntfs files */
        gid_t   gid;                    /* gid that owns ntfs files */
        mode_t  mode;                   /* mask to be applied for ntfs perms */
        u_long  flag;                   /* additional flags */
};

/*
 * ntfs mount options:
 */
#define NTFS_MFLAG_CASEINS      0x00000001
#define NTFS_MFLAG_ALLNAMES     0x00000002

/* Arguments to mount UDF file systems */
struct udf_args {
        char *fspec; /* Block special device to mount */
        u_int32_t lastblock; /* Special device last block */
};

/*
 * Arguments to mount tmpfs file systems
 */
#define TMPFS_ARGS_VERSION      1
struct tmpfs_args {
        int                     ta_version;

        /* Size counters. */
        ino_t                   ta_nodes_max;
        off_t                   ta_size_max;

        /* Root node attributes. */
        uid_t                   ta_root_uid;
        gid_t                   ta_root_gid;
        mode_t                  ta_root_mode;
};

/*
 * Arguments to mount fusefs filesystems
 */
struct fusefs_args {
        char *name;
        int fd;
        int max_read;

        /*
         * FUSE does not allow the file system to be accessed by other users
         * unless this option is specified. This is to prevent unintentional
         * denial of service to other users if the file system is not
         * responding. e.g. user executes df(1) or cron job that scans mounted
         * file systems.
         */
        int allow_other;
};

/*
 * file system statistics
 */

#define MFSNAMELEN      16      /* length of fs type name, including nul */
#define MNAMELEN        90      /* length of buffer for returned name */

/* per-filesystem mount options */
union mount_info {
        struct ufs_args ufs_args;
        struct mfs_args mfs_args;
        struct nfs_args nfs_args;
        struct iso_args iso_args;
        struct msdosfs_args msdosfs_args;
        struct ntfs_args ntfs_args;
        struct tmpfs_args tmpfs_args;
        char __align[160];      /* 64-bit alignment and room to grow */
};

/* new statfs structure with mount options and statvfs fields */
struct statfs {
        u_int32_t       f_flags;        /* copy of mount flags */
        u_int32_t       f_bsize;        /* file system block size */
        u_int32_t       f_iosize;       /* optimal transfer block size */

                                        /* unit is f_bsize */
        u_int64_t       f_blocks;       /* total data blocks in file system */
        u_int64_t       f_bfree;        /* free blocks in fs */
        int64_t         f_bavail;       /* free blocks avail to non-superuser */

        u_int64_t       f_files;        /* total file nodes in file system */
        u_int64_t       f_ffree;        /* free file nodes in fs */
        int64_t         f_favail;       /* free file nodes avail to non-root */

        u_int64_t       f_syncwrites;   /* count of sync writes since mount */
        u_int64_t       f_syncreads;    /* count of sync reads since mount */
        u_int64_t       f_asyncwrites;  /* count of async writes since mount */
        u_int64_t       f_asyncreads;   /* count of async reads since mount */

        fsid_t          f_fsid;         /* file system id */
        u_int32_t       f_namemax;      /* maximum filename length */
        uid_t           f_owner;        /* user that mounted the file system */
        u_int64_t       f_ctime;        /* last mount [-u] time */

        char f_fstypename[MFSNAMELEN];  /* fs type name */
        char f_mntonname[MNAMELEN];     /* directory on which mounted */
        char f_mntfromname[MNAMELEN];   /* mounted file system */
        char f_mntfromspec[MNAMELEN];   /* special for mount request */
        union mount_info mount_info;    /* per-filesystem mount options */
};


/*
 * File system types.
 */
#define MOUNT_FFS       "ffs"           /* UNIX "Fast" Filesystem */
#define MOUNT_UFS       MOUNT_FFS       /* for compatibility */
#define MOUNT_NFS       "nfs"           /* Network Filesystem */
#define MOUNT_MFS       "mfs"           /* Memory Filesystem */
#define MOUNT_MSDOS     "msdos"         /* MSDOS Filesystem */
#define MOUNT_AFS       "afs"           /* Andrew Filesystem */
#define MOUNT_CD9660    "cd9660"        /* ISO9660 (aka CDROM) Filesystem */
#define MOUNT_EXT2FS    "ext2fs"        /* Second Extended Filesystem */
#define MOUNT_NCPFS     "ncpfs"         /* NetWare Network File System */
#define MOUNT_NTFS      "ntfs"          /* NTFS */
#define MOUNT_UDF       "udf"           /* UDF */
#define MOUNT_TMPFS     "tmpfs"         /* tmpfs */
#define MOUNT_FUSEFS    "fuse"          /* FUSE */

/*
 * Structure per mounted file system.  Each mounted file system has an
 * array of operations and an instance record.  The file systems are
 * put on a doubly linked list.
 */
struct mount {
        TAILQ_ENTRY(mount) mnt_list;            /* mount list */
        SLIST_ENTRY(mount) mnt_dounmount;       /* unmount work queue */
        const struct vfsops *mnt_op;            /* operations on fs */
        struct vfsconf  *mnt_vfc;               /* configuration info */
        struct vnode    *mnt_vnodecovered;      /* vnode we mounted on */
        struct vnode    *mnt_syncer;            /* syncer vnode */
        TAILQ_HEAD(, vnode) mnt_vnodelist;      /* list of vnodes this mount */
        struct rwlock   mnt_lock;               /* mount structure lock */
        struct refcnt   mnt_refs;
        int             mnt_flag;               /* flags */
        struct statfs   mnt_stat;               /* cache of filesystem stats */
        void            *mnt_data;              /* private data */
};

/*
 * Mount flags.
 *
 * Unmount uses MNT_FORCE flag.
 */
#define MNT_RDONLY      0x00000001      /* read only filesystem */
#define MNT_SYNCHRONOUS 0x00000002      /* file system written synchronously */
#define MNT_NOEXEC      0x00000004      /* can't exec from filesystem */
#define MNT_NOSUID      0x00000008      /* don't honor setuid bits on fs */
#define MNT_NODEV       0x00000010      /* don't interpret special files */
#define MNT_NOPERM      0x00000020      /* don't enforce permission checks */
#define MNT_ASYNC       0x00000040      /* file system written asynchronously */
#define MNT_WXALLOWED   0x00000800      /* filesystem allows W|X mappings */

/*
 * exported mount flags.
 */
#define MNT_EXRDONLY    0x00000080      /* exported read only */
#define MNT_EXPORTED    0x00000100      /* file system is exported */
#define MNT_DEFEXPORTED 0x00000200      /* exported to the world */
#define MNT_EXPORTANON  0x00000400      /* use anon uid mapping for everyone */

/*
 * Flags set by internal operations.
 */
#define MNT_LOCAL       0x00001000      /* filesystem is stored locally */
#define MNT_QUOTA       0x00002000      /* quotas are enabled on filesystem */
#define MNT_ROOTFS      0x00004000      /* identifies the root filesystem */

/*
 * Extra post 4.4BSD-lite2 mount flags.
 */
#define MNT_NOATIME     0x00008000      /* don't update access times on fs */

/*
 * Mask of flags that are visible to statfs()
 */
#define MNT_VISFLAGMASK 0x0400ffff

#define MNT_BITS \
    "\20\001RDONLY\002SYNCHRONOUS\003NOEXEC\004NOSUID\005NODEV\006NOPERM" \
    "\007ASYNC\010EXRDONLY\011EXPORTED\012DEFEXPORTED\013EXPORTANON" \
    "\014WXALLOWED\015LOCAL\016QUOTA\017ROOTFS\020NOATIME\021UPDATE" \
    "\022DELEXPORT\023RELOAD\024FORCE\025STALLED\026SWAPPABLE\031UNMOUNT" \
    "\032WANTRDWR\033SOFTDEP\034DOOMED"

/*
 * filesystem control flags.
 */
#define MNT_UPDATE      0x00010000      /* not a real mount, just an update */
#define MNT_DELEXPORT   0x00020000      /* delete export host lists */
#define MNT_RELOAD      0x00040000      /* reload filesystem data */
#define MNT_FORCE       0x00080000      /* force unmount or readonly change */
#define MNT_STALLED     0x00100000      /* filesystem stalled */ 
#define MNT_SWAPPABLE   0x00200000      /* filesystem can be used for swap */
#define MNT_UNMOUNT     0x01000000      /* unmount in progress */
#define MNT_WANTRDWR    0x02000000      /* want upgrade to read/write */
#define MNT_SOFTDEP     0x04000000      /* soft dependencies being done - now ignored */
#define MNT_DOOMED      0x08000000      /* device behind filesystem is gone */

#ifdef _KERNEL
#define MNT_OP_FLAGS    (MNT_UPDATE | MNT_RELOAD | MNT_FORCE | MNT_WANTRDWR)
#endif

/*
 * Flags for various system call interfaces.
 *
 * waitfor flags to vfs_sync() and getfsstat()
 */
#define MNT_WAIT        1       /* synchronously wait for I/O to complete */
#define MNT_NOWAIT      2       /* start all I/O, but do not wait for it */
#define MNT_LAZY        3       /* push data not written by filesystem syncer */

/*
 * Generic file handle
 */
struct fhandle {
        fsid_t  fh_fsid;        /* File system id of mount point */
        struct  fid fh_fid;     /* File sys specific id */
};
typedef struct fhandle  fhandle_t;

/*
 * Sysctl CTL_VFS definitions.
 *
 * Second level identifier specifies which filesystem. Second level
 * identifier VFS_GENERIC returns information about all filesystems.
 */
#define VFS_GENERIC     0       /* generic filesystem information */
/*
 * Third level identifiers for VFS_GENERIC are given below; third
 * level identifiers for specific filesystems are given in their
 * mount specific header files.
 */
#define VFS_MAXTYPENUM  1       /* int: highest defined filesystem type */
#define VFS_CONF        2       /* struct: vfsconf for filesystem given
                                   as next argument */
#define VFS_BCACHESTAT  3       /* struct: buffer cache statistics given 
                                   as next argument */
#define CTL_VFSGENCTL_NAMES { \
        { 0, 0 }, \
        { "maxtypenum", CTLTYPE_INT }, \
        { "conf", CTLTYPE_NODE }, \
        { "bcachestat", CTLTYPE_STRUCT } \
}

/*
 * Filesystem configuration information. One of these exists for each
 * type of filesystem supported by the kernel. These are searched at
 * mount time to identify the requested filesystem.
 */
struct vfsconf {
        const struct vfsops *vfc_vfsops; /* filesystem operations vector */
        char    vfc_name[MFSNAMELEN];   /* filesystem type name */
        int     vfc_typenum;            /* historic filesystem type number */
        u_int   vfc_refcount;           /* number mounted of this type */
        int     vfc_flags;              /* permanent flags */
        size_t  vfc_datasize;           /* size of data args */
};

/* buffer cache statistics */
struct bcachestats {
        int64_t numbufs;                /* number of buffers allocated */
        int64_t numbufpages;            /* number of pages in buffer cache */
        int64_t numdirtypages;          /* number of dirty free pages */
        int64_t numcleanpages;          /* number of clean free pages */
        int64_t pendingwrites;          /* number of pending writes */
        int64_t pendingreads;           /* number of pending reads */
        int64_t numwrites;              /* total writes started */
        int64_t numreads;               /* total reads started */
        int64_t cachehits;              /* total reads found in cache */
        int64_t busymapped;             /* number of busy and mapped buffers */
        int64_t dmapages;               /* dma reachable pages in buffer cache */
        int64_t highpages;              /* pages above dma region */
        int64_t delwribufs;             /* delayed write buffers */
        int64_t kvaslots;               /* kva slots total */
        int64_t kvaslots_avail;         /* available kva slots */
        int64_t highflips;              /* total flips to above DMA */
        int64_t highflops;              /* total failed flips to above DMA */
        int64_t dmaflips;               /* total flips from high to DMA */
};
#ifdef _KERNEL
extern struct bcachestats bcstats;
extern long buflowpages, bufhighpages, bufbackpages;
#define BUFPAGES_DEFICIT (((buflowpages - bcstats.numbufpages) < 0) ? 0 \
    : buflowpages - bcstats.numbufpages)
#define BUFPAGES_INACT (((bcstats.numcleanpages - buflowpages) < 0) ? 0 \
    : bcstats.numcleanpages - buflowpages)
extern int bufcachepercent;
extern void bufadjust(int);
struct uvm_constraint_range;
extern unsigned long bufbackoff(struct uvm_constraint_range*, long);

/*
 * Operations supported on mounted file system.
 */
struct nameidata;
struct mbuf;

extern int maxvfsconf;          /* highest defined filesystem type */

struct vfsops {
        int     (*vfs_mount)(struct mount *mp, const char *path,
                                    void *data,
                                    struct nameidata *ndp, struct proc *p);
        int     (*vfs_start)(struct mount *mp, int flags,
                                    struct proc *p);
        int     (*vfs_unmount)(struct mount *mp, int mntflags,
                                    struct proc *p);
        int     (*vfs_root)(struct mount *mp, struct vnode **vpp);
        int     (*vfs_quotactl)(struct mount *mp, int cmds, uid_t uid,
                                    caddr_t arg, struct proc *p);
        int     (*vfs_statfs)(struct mount *mp, struct statfs *sbp,
                                    struct proc *p);
        int     (*vfs_sync)(struct mount *mp, int waitfor, int stall,
                                    struct ucred *cred, struct proc *p);
        int     (*vfs_vget)(struct mount *mp, ino_t ino,
                                    struct vnode **vpp);
        int     (*vfs_fhtovp)(struct mount *mp, struct fid *fhp,
                                     struct vnode **vpp);
        int     (*vfs_vptofh)(struct vnode *vp, struct fid *fhp);
        int     (*vfs_init)(struct vfsconf *);
        int     (*vfs_sysctl)(int *, u_int, void *, size_t *, void *,
                                     size_t, struct proc *);
        int     (*vfs_checkexp)(struct mount *mp, struct mbuf *nam,
                                    int *extflagsp, struct ucred **credanonp);
};

#define VFS_MOUNT(MP, PATH, DATA, NDP, P) \
        (*(MP)->mnt_op->vfs_mount)(MP, PATH, DATA, NDP, P)
#define VFS_START(MP, FLAGS, P)   (*(MP)->mnt_op->vfs_start)(MP, FLAGS, P)
#define VFS_UNMOUNT(MP, FORCE, P) (*(MP)->mnt_op->vfs_unmount)(MP, FORCE, P)
#define VFS_ROOT(MP, VPP)         (*(MP)->mnt_op->vfs_root)(MP, VPP)
#define VFS_QUOTACTL(MP,C,U,A,P)  (*(MP)->mnt_op->vfs_quotactl)(MP, C, U, A, P)
#define VFS_STATFS(MP, SBP, P)    (*(MP)->mnt_op->vfs_statfs)(MP, SBP, P)
#define VFS_SYNC(MP, W, S, C, P)  (*(MP)->mnt_op->vfs_sync)(MP, W, S, C, P)
#define VFS_VGET(MP, INO, VPP)    (*(MP)->mnt_op->vfs_vget)(MP, INO, VPP)
#define VFS_FHTOVP(MP, FIDP, VPP) \
        (*(MP)->mnt_op->vfs_fhtovp)(MP, FIDP, VPP)
#define VFS_VPTOFH(VP, FIDP)      (*(VP)->v_mount->mnt_op->vfs_vptofh)(VP, FIDP)
#define VFS_CHECKEXP(MP, NAM, EXFLG, CRED) \
        (*(MP)->mnt_op->vfs_checkexp)(MP, NAM, EXFLG, CRED)

/* Set up the filesystem operations for vnodes. */
extern  const struct vfsops ffs_vfsops;
extern  const struct vfsops mfs_vfsops;
extern  const struct vfsops msdosfs_vfsops;
extern  const struct vfsops nfs_vfsops;
extern  const struct vfsops cd9660_vfsops;
extern  const struct vfsops ext2fs_vfsops;
extern  const struct vfsops ntfs_vfsops;
extern  const struct vfsops udf_vfsops;
extern  const struct vfsops fusefs_vfsops;
extern  const struct vfsops tmpfs_vfsops;

#include <net/radix.h>
#include <sys/socket.h>         /* XXX for AF_MAX */

/*
 * Network address lookup element
 */
struct netcred {
        struct  radix_node netc_rnodes[2];
        int     netc_exflags;
        int     netc_len;                       /* size of the allocation */
        struct  ucred netc_anon;
};

/*
 * Network export information
 */
struct netexport {
        struct  netcred ne_defexported;         /* Default export */
        struct  radix_node_head *ne_rtable_inet;/* Individual exports */
};

/*
 * exported vnode operations
 */
int     vfs_busy(struct mount *, int);
#define VB_READ         0x01
#define VB_WRITE        0x02
#define VB_NOWAIT       0x04    /* immediately fail on busy lock */
#define VB_WAIT         0x08    /* sleep fail on busy lock */
#define VB_DUPOK        0x10    /* permit duplicate mount busying */

int     vfs_isbusy(struct mount *);
struct  mount *vfs_mount_alloc(struct vnode *, struct vfsconf *);
void    vfs_mount_free(struct mount *);
int     vfs_mount_foreach_vnode(struct mount *, int (*func)(struct vnode *,
                                    void *), void *);
void    vfs_getnewfsid(struct mount *);
struct  mount *vfs_getvfs(fsid_t *);
int     vfs_mountedon(struct vnode *);
int     vfs_rootmountalloc(char *, char *, struct mount **);
void    vfs_unbusy(struct mount *);
extern  TAILQ_HEAD(mntlist, mount) mountlist;
int     vfs_stall(struct proc *, int);
void    vfs_stall_barrier(void);

                                            /* process mount export info */
int     vfs_export(struct mount *, struct netexport *, struct export_args *);
                                            /* lookup host in fs export list */
struct  netcred *vfs_export_lookup(struct mount *, struct netexport *,
            struct mbuf *);
int     vfs_allocate_syncvnode(struct mount *);

int     vfs_syncwait(struct proc *, int);   /* sync and wait for complete */
void    vfs_shutdown(struct proc *);        /* unmount and sync file systems */
int     dounmount(struct mount *, int, struct proc *);
void    vfsinit(void);
struct  vfsconf *vfs_byname(const char *);
struct  vfsconf *vfs_bytypenum(int);
#else /* _KERNEL */
__BEGIN_DECLS
int     fstatfs(int, struct statfs *);
int     getfh(const char *, fhandle_t *);
int     getfsstat(struct statfs *, size_t, int);
int     getmntinfo(struct statfs **, int);
int     mount(const char *, const char *, int, void *);
int     statfs(const char *, struct statfs *);
int     unmount(const char *, int);
#if __BSD_VISIBLE
struct stat;
int     fhopen(const fhandle_t *, int);
int     fhstat(const fhandle_t *, struct stat *);
int     fhstatfs(const fhandle_t *, struct statfs *);
#endif /* __BSD_VISIBLE */
__END_DECLS
#endif /* _KERNEL */
#endif /* !_SYS_MOUNT_H_ */