bsd/sys/mount_internal.h

   1 /*
   2  * Copyright (c) 2000-2005 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 /* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
  29 /*
  30  * Copyright (c) 1989, 1991, 1993
  31  *      The Regents of the University of California.  All rights reserved.
  32  *
  33  * Redistribution and use in source and binary forms, with or without
  34  * modification, are permitted provided that the following conditions
  35  * are met:
  36  * 1. Redistributions of source code must retain the above copyright
  37  *    notice, this list of conditions and the following disclaimer.
  38  * 2. Redistributions in binary form must reproduce the above copyright
  39  *    notice, this list of conditions and the following disclaimer in the
  40  *    documentation and/or other materials provided with the distribution.
  41  * 3. All advertising materials mentioning features or use of this software
  42  *    must display the following acknowledgement:
  43  *      This product includes software developed by the University of
  44  *      California, Berkeley and its contributors.
  45  * 4. Neither the name of the University nor the names of its contributors
  46  *    may be used to endorse or promote products derived from this software
  47  *    without specific prior written permission.
  48  *
  49  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  50  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  51  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  52  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  53  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  54  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  55  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  56  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  57  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  58  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  59  * SUCH DAMAGE.
  60  *
  61  *      @(#)mount.h     8.21 (Berkeley) 5/20/95
  62  */
  63
  64 #ifndef _SYS_MOUNT_INTERNAL_H_
  65 #define _SYS_MOUNT_INTERNAL_H_
  66
  67 #include <sys/appleapiopts.h>
  68 #ifndef KERNEL
  69 #include <sys/ucred.h>
  70 #else
  71 #include <sys/kernel_types.h>
  72 #include <sys/namei.h>
  73 #endif
  74 #include <sys/queue.h>
  75 #include <sys/lock.h>
  76 #include <net/radix.h>
  77 #include <sys/socket.h>         /* XXX for AF_MAX */
  78 #include <sys/vfs_context.h>            /* XXX for AF_MAX */
  79 #include <sys/mount.h>
  80 #include <sys/cdefs.h>
  81
  82 /*
  83  * Structure per mounted file system.  Each mounted file system has an
  84  * array of operations and an instance record.  The file systems are
  85  * put on a doubly linked list.
  86  */
  87 TAILQ_HEAD(vnodelst, vnode);
  88
  89 struct mount {
  90         TAILQ_ENTRY(mount) mnt_list;            /* mount list */
  91         int32_t         mnt_count;              /* reference on the mount */
  92         lck_mtx_t       mnt_mlock;              /* mutex that protects mount point */
  93         struct vfsops   *mnt_op;                /* operations on fs */
  94         struct vfstable *mnt_vtable;            /* configuration info */
  95         struct vnode    *mnt_vnodecovered;      /* vnode we mounted on */
  96         struct vnodelst mnt_vnodelist;          /* list of vnodes this mount */
  97         struct vnodelst mnt_workerqueue;                /* list of vnodes this mount */
  98         struct vnodelst mnt_newvnodes;          /* list of vnodes this mount */
  99         int             mnt_flag;               /* flags */
 100         int             mnt_kern_flag;          /* kernel only flags */
 101         int             mnt_lflag;                      /* mount life cycle flags */
 102         int             mnt_maxsymlinklen;      /* max size of short symlink */
 103         struct vfsstatfs        mnt_vfsstat;            /* cache of filesystem stats */
 104         qaddr_t         mnt_data;               /* private data */
 105         /* Cached values of the IO constraints for the device */
 106         u_int32_t       mnt_maxreadcnt;         /* Max. byte count for read */
 107         u_int32_t       mnt_maxwritecnt;        /* Max. byte count for write */
 108         u_int32_t       mnt_segreadcnt;         /* Max. segment count for read */
 109         u_int32_t       mnt_segwritecnt;        /* Max. segment count for write */
 110         u_int32_t       mnt_maxsegreadsize;     /* Max. segment read size  */
 111         u_int32_t       mnt_maxsegwritesize;    /* Max. segment write size */
 112         u_int32_t       mnt_devblocksize;       /* the underlying device block size */
 113         lck_rw_t        mnt_rwlock;             /* mutex readwrite lock */
 114         lck_mtx_t       mnt_renamelock;         /* mutex that serializes renames that change shape of tree */
 115         vnode_t         mnt_devvp;              /* the device mounted on for local file systems */
 116         int32_t         mnt_crossref;           /* refernces to cover lookups  crossing into mp */
 117         int32_t         mnt_iterref;            /* refernces to cover iterations; drained makes it -ve  */
 118
 119         /* XXX 3762912 hack to support HFS filesystem 'owner' */
 120         uid_t           mnt_fsowner;
 121         gid_t           mnt_fsgroup;
 122 };
 123
 124 /* XXX 3762912 hack to support HFS filesystem 'owner' */
 125 #define vfs_setowner(_mp, _uid, _gid)   do {(_mp)->mnt_fsowner = (_uid); (_mp)->mnt_fsgroup = (_gid); } while (0)
 126
 127
 128 /* mount point to which dead vps point to */
 129 extern struct mount * dead_mountp;
 130
 131 /*
 132  * Internal filesystem control flags stored in mnt_kern_flag.
 133  *
 134  * MNTK_UNMOUNT locks the mount entry so that name lookup cannot proceed
 135  * past the mount point.  This keeps the subtree stable during mounts
 136  * and unmounts.
 137  *
 138  * Note:        We are counting down on new bit assignments.  This is
 139  *              because the bits here were broken out from the high bits
 140  *              of the mount flags.
 141  */
 142 #define MNTK_LOCK_LOCAL         0x00100000      /* advisory locking is done above the VFS itself */
 143 #define MNTK_VIRTUALDEV         0x00200000      /* mounted on a virtual device i.e. a disk image */
 144 #define MNTK_ROOTDEV            0x00400000      /* this filesystem resides on the same device as the root */
 145 #define MNTK_UNMOUNT            0x01000000      /* unmount in progress */
 146 #define MNTK_MWAIT              0x02000000      /* waiting for unmount to finish */
 147 #define MNTK_WANTRDWR           0x04000000      /* upgrade to read/write requested */
 148 #if REV_ENDIAN_FS
 149 #define MNT_REVEND              0x08000000      /* Reverse endian FS */
 150 #endif /* REV_ENDIAN_FS */
 151 #define MNTK_FRCUNMOUNT         0x10000000      /* Forced unmount wanted. */
 152 #define MNTK_AUTH_OPAQUE        0x20000000      /* authorisation decisions are not made locally */
 153 #define MNTK_AUTH_OPAQUE_ACCESS 0x40000000      /* VNOP_ACCESS is reliable for remote auth */
 154 #define MNTK_EXTENDED_SECURITY  0x80000000      /* extended security supported */
 155
 156 #define MNT_LBUSY               0x00000001      /* mount is busy */
 157 #define MNT_LUNMOUNT            0x00000002      /* mount in unmount */
 158 #define MNT_LFORCE              0x00000004      /* mount in forced unmount */
 159 #define MNT_LDRAIN              0x00000008      /* mount in drain */
 160 #define MNT_LITER               0x00000010      /* mount in iteration */
 161 #define MNT_LNEWVN              0x00000020      /* mount has new vnodes created */
 162 #define MNT_LWAIT               0x00000040      /* wait for unmount op */
 163 #define MNT_LITERWAIT           0x00000080      /* mount in iteration */
 164 #define MNT_LDEAD               0x00000100      /* mount already unmounted*/
 165
 166
 167 /*
 168  * Generic file handle
 169  */
 170 #define NFS_MAX_FH_SIZE         64
 171 #define NFSV2_MAX_FH_SIZE       32
 172 struct fhandle {
 173         int             fh_len;                         /* length of file handle */
 174         unsigned char   fh_data[NFS_MAX_FH_SIZE];       /* file handle value */
 175 };
 176 typedef struct fhandle  fhandle_t;
 177
 178
 179
 180 /*
 181  * Filesystem configuration information. One of these exists for each
 182  * type of filesystem supported by the kernel. These are searched at
 183  * mount time to identify the requested filesystem.
 184  */
 185 struct vfstable {
 186 /* THE FOLLOWING SHOULD KEEP THE SAME FOR user compat with sysctl */
 187         struct  vfsops *vfc_vfsops;     /* filesystem operations vector */
 188         char    vfc_name[MFSNAMELEN];   /* filesystem type name */
 189         int     vfc_typenum;            /* historic filesystem type number */
 190         int     vfc_refcount;           /* number mounted of this type */
 191         int     vfc_flags;              /* permanent flags */
 192         int     (*vfc_mountroot)(mount_t, vnode_t, vfs_context_t);      /* if != NULL, routine to mount root */
 193         struct  vfstable *vfc_next;     /* next in list */
 194 /* Till the above we SHOULD KEEP THE SAME FOR user compat with sysctl */
 195         int         vfc_threadsafe;     /* FS is thread & premeption safe */
 196         lck_mtx_t   vfc_lock;           /* for non-threaded file systems */
 197         int             vfc_vfsflags;   /* for optional types */
 198         void *          vfc_descptr;    /* desc table allocated address */
 199         int                     vfc_descsize;   /* size allocated for desc table */
 200         int             vfc_64bitready; /* The file system is ready for 64bit */
 201 };
 202
 203 #define VFC_VFSLOCALARGS        0x02
 204 #define VFC_VFSGENERICARGS      0x04
 205 #define VFC_VFSNATIVEXATTR      0x10
 206
 207
 208 extern int maxvfsconf;          /* highest defined filesystem type */
 209 extern struct vfstable  *vfsconf;       /* head of list of filesystem types */
 210 extern int maxvfsslots;         /* Maximum slots available to be used */
 211 extern int numused_vfsslots;    /* number of slots already used */
 212
 213 /* the following two are xnu private */
 214 struct vfstable *       vfstable_add(struct     vfstable *);
 215 int     vfstable_del(struct vfstable *);
 216
 217
 218 struct vfsmount_args {
 219         union {
 220                 struct {
 221                         char * mnt_fspec;
 222                         void * mnt_fsdata;
 223                 } mnt_localfs_args;
 224                 struct {
 225                         void *  mnt_fsdata;             /* FS specific */
 226                 } mnt_remotefs_args;
 227         } mountfs_args;
 228 };
 229
 230
 231 /*
 232  * LP64 version of statfs structure.
 233  * NOTE - must be kept in sync with struct statfs in mount.h
 234  */
 235 #if __DARWIN_ALIGN_NATURAL
 236 #pragma options align=natural
 237 #endif
 238
 239 struct user_statfs {
 240         short           f_otype;                /* TEMPORARY SHADOW COPY OF f_type */
 241         short           f_oflags;               /* TEMPORARY SHADOW COPY OF f_flags */
 242         user_long_t     f_bsize;                /* fundamental file system block size */
 243         user_long_t     f_iosize;               /* optimal transfer block size */
 244         user_long_t     f_blocks;               /* total data blocks in file system */
 245         user_long_t     f_bfree;                /* free blocks in fs */
 246         user_long_t     f_bavail;               /* free blocks avail to non-superuser */
 247         user_long_t     f_files;                /* total file nodes in file system */
 248         user_long_t     f_ffree;                /* free file nodes in fs */
 249         fsid_t          f_fsid;                 /* file system id */
 250         uid_t           f_owner;                /* user that mounted the filesystem */
 251         short           f_reserved1;    /* spare for later */
 252         short           f_type;                 /* type of filesystem */
 253     user_long_t f_flags;                /* copy of mount exported flags */
 254         user_long_t f_reserved2[2];     /* reserved for future use */
 255         char            f_fstypename[MFSNAMELEN]; /* fs type name */
 256         char            f_mntonname[MNAMELEN];  /* directory on which mounted */
 257         char            f_mntfromname[MNAMELEN];/* mounted filesystem */
 258 #if COMPAT_GETFSSTAT
 259         char            f_reserved3[0]; /* For alignment */
 260         user_long_t     f_reserved4[0]; /* For future use */
 261 #else
 262         char            f_reserved3;    /* For alignment */
 263         user_long_t     f_reserved4[4]; /* For future use */
 264 #endif
 265 };
 266
 267 #if __DARWIN_ALIGN_NATURAL
 268 #pragma options align=reset
 269 #endif
 270
 271 __BEGIN_DECLS
 272
 273 extern TAILQ_HEAD(mntlist, mount) mountlist;
 274 void mount_list_lock(void);
 275 void mount_list_unlock(void);
 276 void mount_lock_init(mount_t);
 277 void mount_lock_destroy(mount_t);
 278 void mount_lock(mount_t);
 279 void mount_unlock(mount_t);
 280 void mount_lock_renames(mount_t);
 281 void mount_unlock_renames(mount_t);
 282 void mount_ref(mount_t, int);
 283 void mount_drop(mount_t, int);
 284
 285 /* vfs_rootmountalloc should be kept as a private api */
 286 errno_t vfs_rootmountalloc(const char *, const char *, mount_t *mpp);
 287 errno_t vfs_init_io_attributes(vnode_t, mount_t);
 288
 289 int     vfs_mountroot(void);
 290 void    vfs_unmountall(void);
 291 int     safedounmount(struct mount *, int, struct proc *);
 292 int     dounmount(struct mount *, int, struct proc *);
 293
 294 /* xnuy internal api */
 295 void  mount_dropcrossref(mount_t, vnode_t, int);
 296 int validfsnode(mount_t);
 297 mount_t mount_lookupby_volfsid(int, int);
 298 mount_t mount_list_lookupby_fsid(fsid_t *, int, int);
 299 int  mount_iterref(mount_t, int);
 300 int  mount_isdrained(mount_t, int);
 301 void mount_iterdrop(mount_t);
 302 void mount_iterdrain(mount_t);
 303 void mount_iterreset(mount_t);
 304
 305 __END_DECLS
 306
 307 #endif /* !_SYS_MOUNT_INTERNAL_H_ */