bsd/sys/mount_internal.h

   1 /*
   2  * Copyright (c) 2000-2005 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22 /* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
  23 /*
  24  * Copyright (c) 1989, 1991, 1993
  25  *      The Regents of the University of California.  All rights reserved.
  26  *
  27  * Redistribution and use in source and binary forms, with or without
  28  * modification, are permitted provided that the following conditions
  29  * are met:
  30  * 1. Redistributions of source code must retain the above copyright
  31  *    notice, this list of conditions and the following disclaimer.
  32  * 2. Redistributions in binary form must reproduce the above copyright
  33  *    notice, this list of conditions and the following disclaimer in the
  34  *    documentation and/or other materials provided with the distribution.
  35  * 3. All advertising materials mentioning features or use of this software
  36  *    must display the following acknowledgement:
  37  *      This product includes software developed by the University of
  38  *      California, Berkeley and its contributors.
  39  * 4. Neither the name of the University nor the names of its contributors
  40  *    may be used to endorse or promote products derived from this software
  41  *    without specific prior written permission.
  42  *
  43  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  44  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  45  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  46  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  47  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  48  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  49  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  50  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  51  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  52  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  53  * SUCH DAMAGE.
  54  *
  55  *      @(#)mount.h     8.21 (Berkeley) 5/20/95
  56  */
  57
  58 #ifndef _SYS_MOUNT_INTERNAL_H_
  59 #define _SYS_MOUNT_INTERNAL_H_
  60
  61 #include <sys/appleapiopts.h>
  62 #ifndef KERNEL
  63 #include <sys/ucred.h>
  64 #else
  65 #include <sys/kernel_types.h>
  66 #include <sys/namei.h>
  67 #endif
  68 #include <sys/queue.h>
  69 #include <sys/lock.h>
  70 #include <net/radix.h>
  71 #include <sys/socket.h>         /* XXX for AF_MAX */
  72 #include <sys/vfs_context.h>            /* XXX for AF_MAX */
  73 #include <sys/mount.h>
  74 #include <sys/cdefs.h>
  75
  76 /*
  77  * Structure per mounted file system.  Each mounted file system has an
  78  * array of operations and an instance record.  The file systems are
  79  * put on a doubly linked list.
  80  */
  81 TAILQ_HEAD(vnodelst, vnode);
  82
  83 struct mount {
  84         TAILQ_ENTRY(mount) mnt_list;            /* mount list */
  85         int32_t         mnt_count;              /* reference on the mount */
  86         lck_mtx_t       mnt_mlock;              /* mutex that protects mount point */
  87         struct vfsops   *mnt_op;                /* operations on fs */
  88         struct vfstable *mnt_vtable;            /* configuration info */
  89         struct vnode    *mnt_vnodecovered;      /* vnode we mounted on */
  90         struct vnodelst mnt_vnodelist;          /* list of vnodes this mount */
  91         struct vnodelst mnt_workerqueue;                /* list of vnodes this mount */
  92         struct vnodelst mnt_newvnodes;          /* list of vnodes this mount */
  93         int             mnt_flag;               /* flags */
  94         int             mnt_kern_flag;          /* kernel only flags */
  95         int             mnt_lflag;                      /* mount life cycle flags */
  96         int             mnt_maxsymlinklen;      /* max size of short symlink */
  97         struct vfsstatfs        mnt_vfsstat;            /* cache of filesystem stats */
  98         qaddr_t         mnt_data;               /* private data */
  99         /* Cached values of the IO constraints for the device */
 100         u_int32_t       mnt_maxreadcnt;         /* Max. byte count for read */
 101         u_int32_t       mnt_maxwritecnt;        /* Max. byte count for write */
 102         u_int32_t       mnt_segreadcnt;         /* Max. segment count for read */
 103         u_int32_t       mnt_segwritecnt;        /* Max. segment count for write */
 104         u_int32_t       mnt_maxsegreadsize;     /* Max. segment read size  */
 105         u_int32_t       mnt_maxsegwritesize;    /* Max. segment write size */
 106         u_int32_t       mnt_devblocksize;       /* the underlying device block size */
 107         lck_rw_t        mnt_rwlock;             /* mutex readwrite lock */
 108         lck_mtx_t       mnt_renamelock;         /* mutex that serializes renames that change shape of tree */
 109         vnode_t         mnt_devvp;              /* the device mounted on for local file systems */
 110         int32_t         mnt_crossref;           /* refernces to cover lookups  crossing into mp */
 111         int32_t         mnt_iterref;            /* refernces to cover iterations; drained makes it -ve  */
 112
 113         /* XXX 3762912 hack to support HFS filesystem 'owner' */
 114         uid_t           mnt_fsowner;
 115         gid_t           mnt_fsgroup;
 116 };
 117
 118 /* XXX 3762912 hack to support HFS filesystem 'owner' */
 119 #define vfs_setowner(_mp, _uid, _gid)   do {(_mp)->mnt_fsowner = (_uid); (_mp)->mnt_fsgroup = (_gid); } while (0)
 120
 121
 122 /* mount point to which dead vps point to */
 123 extern struct mount * dead_mountp;
 124
 125 /*
 126  * Internal filesystem control flags stored in mnt_kern_flag.
 127  *
 128  * MNTK_UNMOUNT locks the mount entry so that name lookup cannot proceed
 129  * past the mount point.  This keeps the subtree stable during mounts
 130  * and unmounts.
 131  *
 132  * Note:        We are counting down on new bit assignments.  This is
 133  *              because the bits here were broken out from the high bits
 134  *              of the mount flags.
 135  */
 136 #define MNTK_LOCK_LOCAL         0x00100000      /* advisory locking is done above the VFS itself */
 137 #define MNTK_VIRTUALDEV         0x00200000      /* mounted on a virtual device i.e. a disk image */
 138 #define MNTK_ROOTDEV            0x00400000      /* this filesystem resides on the same device as the root */
 139 #define MNTK_UNMOUNT            0x01000000      /* unmount in progress */
 140 #define MNTK_MWAIT              0x02000000      /* waiting for unmount to finish */
 141 #define MNTK_WANTRDWR           0x04000000      /* upgrade to read/write requested */
 142 #if REV_ENDIAN_FS
 143 #define MNT_REVEND              0x08000000      /* Reverse endian FS */
 144 #endif /* REV_ENDIAN_FS */
 145 #define MNTK_FRCUNMOUNT         0x10000000      /* Forced unmount wanted. */
 146 #define MNTK_AUTH_OPAQUE        0x20000000      /* authorisation decisions are not made locally */
 147 #define MNTK_AUTH_OPAQUE_ACCESS 0x40000000      /* VNOP_ACCESS is reliable for remote auth */
 148 #define MNTK_EXTENDED_SECURITY  0x80000000      /* extended security supported */
 149
 150 #define MNT_LBUSY               0x00000001      /* mount is busy */
 151 #define MNT_LUNMOUNT            0x00000002      /* mount in unmount */
 152 #define MNT_LFORCE              0x00000004      /* mount in forced unmount */
 153 #define MNT_LDRAIN              0x00000008      /* mount in drain */
 154 #define MNT_LITER               0x00000010      /* mount in iteration */
 155 #define MNT_LNEWVN              0x00000020      /* mount has new vnodes created */
 156 #define MNT_LWAIT               0x00000040      /* wait for unmount op */
 157 #define MNT_LITERWAIT           0x00000080      /* mount in iteration */
 158 #define MNT_LDEAD               0x00000100      /* mount already unmounted*/
 159
 160
 161 /*
 162  * Generic file handle
 163  */
 164 #define NFS_MAX_FH_SIZE         64
 165 #define NFSV2_MAX_FH_SIZE       32
 166 struct fhandle {
 167         int             fh_len;                         /* length of file handle */
 168         unsigned char   fh_data[NFS_MAX_FH_SIZE];       /* file handle value */
 169 };
 170 typedef struct fhandle  fhandle_t;
 171
 172
 173
 174 /*
 175  * Filesystem configuration information. One of these exists for each
 176  * type of filesystem supported by the kernel. These are searched at
 177  * mount time to identify the requested filesystem.
 178  */
 179 struct vfstable {
 180 /* THE FOLLOWING SHOULD KEEP THE SAME FOR user compat with sysctl */
 181         struct  vfsops *vfc_vfsops;     /* filesystem operations vector */
 182         char    vfc_name[MFSNAMELEN];   /* filesystem type name */
 183         int     vfc_typenum;            /* historic filesystem type number */
 184         int     vfc_refcount;           /* number mounted of this type */
 185         int     vfc_flags;              /* permanent flags */
 186         int     (*vfc_mountroot)(mount_t, vnode_t, vfs_context_t);      /* if != NULL, routine to mount root */
 187         struct  vfstable *vfc_next;     /* next in list */
 188 /* Till the above we SHOULD KEEP THE SAME FOR user compat with sysctl */
 189         int         vfc_threadsafe;     /* FS is thread & premeption safe */
 190         lck_mtx_t   vfc_lock;           /* for non-threaded file systems */
 191         int             vfc_vfsflags;   /* for optional types */
 192         void *          vfc_descptr;    /* desc table allocated address */
 193         int                     vfc_descsize;   /* size allocated for desc table */
 194         int             vfc_64bitready; /* The file system is ready for 64bit */
 195 };
 196
 197 #define VFC_VFSLOCALARGS        0x02
 198 #define VFC_VFSGENERICARGS      0x04
 199 #define VFC_VFSNATIVEXATTR      0x10
 200
 201
 202 extern int maxvfsconf;          /* highest defined filesystem type */
 203 extern struct vfstable  *vfsconf;       /* head of list of filesystem types */
 204 extern int maxvfsslots;         /* Maximum slots available to be used */
 205 extern int numused_vfsslots;    /* number of slots already used */
 206
 207 /* the following two are xnu private */
 208 struct vfstable *       vfstable_add(struct     vfstable *);
 209 int     vfstable_del(struct vfstable *);
 210
 211
 212 struct vfsmount_args {
 213         union {
 214                 struct {
 215                         char * mnt_fspec;
 216                         void * mnt_fsdata;
 217                 } mnt_localfs_args;
 218                 struct {
 219                         void *  mnt_fsdata;             /* FS specific */
 220                 } mnt_remotefs_args;
 221         } mountfs_args;
 222 };
 223
 224
 225 /*
 226  * LP64 version of statfs structure.
 227  * NOTE - must be kept in sync with struct statfs in mount.h
 228  */
 229 #if __DARWIN_ALIGN_NATURAL
 230 #pragma options align=natural
 231 #endif
 232
 233 struct user_statfs {
 234         short           f_otype;                /* TEMPORARY SHADOW COPY OF f_type */
 235         short           f_oflags;               /* TEMPORARY SHADOW COPY OF f_flags */
 236         user_long_t     f_bsize;                /* fundamental file system block size */
 237         user_long_t     f_iosize;               /* optimal transfer block size */
 238         user_long_t     f_blocks;               /* total data blocks in file system */
 239         user_long_t     f_bfree;                /* free blocks in fs */
 240         user_long_t     f_bavail;               /* free blocks avail to non-superuser */
 241         user_long_t     f_files;                /* total file nodes in file system */
 242         user_long_t     f_ffree;                /* free file nodes in fs */
 243         fsid_t          f_fsid;                 /* file system id */
 244         uid_t           f_owner;                /* user that mounted the filesystem */
 245         short           f_reserved1;    /* spare for later */
 246         short           f_type;                 /* type of filesystem */
 247     user_long_t f_flags;                /* copy of mount exported flags */
 248         user_long_t f_reserved2[2];     /* reserved for future use */
 249         char            f_fstypename[MFSNAMELEN]; /* fs type name */
 250         char            f_mntonname[MNAMELEN];  /* directory on which mounted */
 251         char            f_mntfromname[MNAMELEN];/* mounted filesystem */
 252 #if COMPAT_GETFSSTAT
 253         char            f_reserved3[0]; /* For alignment */
 254         user_long_t     f_reserved4[0]; /* For future use */
 255 #else
 256         char            f_reserved3;    /* For alignment */
 257         user_long_t     f_reserved4[4]; /* For future use */
 258 #endif
 259 };
 260
 261 #if __DARWIN_ALIGN_NATURAL
 262 #pragma options align=reset
 263 #endif
 264
 265 __BEGIN_DECLS
 266
 267 extern TAILQ_HEAD(mntlist, mount) mountlist;
 268 void mount_list_lock(void);
 269 void mount_list_unlock(void);
 270 void mount_lock_init(mount_t);
 271 void mount_lock_destroy(mount_t);
 272 void mount_lock(mount_t);
 273 void mount_unlock(mount_t);
 274 void mount_lock_renames(mount_t);
 275 void mount_unlock_renames(mount_t);
 276 void mount_ref(mount_t, int);
 277 void mount_drop(mount_t, int);
 278
 279 /* vfs_rootmountalloc should be kept as a private api */
 280 errno_t vfs_rootmountalloc(const char *, const char *, mount_t *mpp);
 281 errno_t vfs_init_io_attributes(vnode_t, mount_t);
 282
 283 int     vfs_mountroot(void);
 284 void    vfs_unmountall(void);
 285 int     safedounmount(struct mount *, int, struct proc *);
 286 int     dounmount(struct mount *, int, struct proc *);
 287
 288 /* xnuy internal api */
 289 void  mount_dropcrossref(mount_t, vnode_t, int);
 290 int validfsnode(mount_t);
 291 mount_t mount_lookupby_volfsid(int, int);
 292 mount_t mount_list_lookupby_fsid(fsid_t *, int, int);
 293 int  mount_iterref(mount_t, int);
 294 int  mount_isdrained(mount_t, int);
 295 void mount_iterdrop(mount_t);
 296 void mount_iterdrain(mount_t);
 297 void mount_iterreset(mount_t);
 298
 299 __END_DECLS
 300
 301 #endif /* !_SYS_MOUNT_INTERNAL_H_ */