2 * Copyright (c) 2000-2018 Apple Inc. All rights reserved.
4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
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
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28 /* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
30 * Copyright (c) 1989, 1991, 1993
31 * The Regents of the University of California. All rights reserved.
33 * Redistribution and use in source and binary forms, with or without
34 * modification, are permitted provided that the following conditions
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.
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
61 * @(#)mount.h 8.21 (Berkeley) 5/20/95
64 * NOTICE: This file was modified by McAfee Research in 2004 to introduce
65 * support for mandatory and extensible security protections. This notice
66 * is included in support of clause 2.2 (b) of the Apple Public License,
70 #ifndef _SYS_MOUNT_INTERNAL_H_
71 #define _SYS_MOUNT_INTERNAL_H_
73 #include <sys/appleapiopts.h>
75 #include <sys/ucred.h>
77 #include <sys/kernel_types.h>
78 #include <sys/namei.h>
80 #include <sys/queue.h>
82 #include <net/radix.h>
83 #include <sys/socket.h> /* XXX for AF_MAX */
84 #include <sys/vfs_context.h> /* XXX for AF_MAX */
85 #include <sys/mount.h>
86 #include <sys/cdefs.h>
87 #include <sys/sysctl.h>
91 #if defined(__i386__) || defined(__x86_64__)
92 typedef uint64_t pending_io_t
;
93 #define INCR_PENDING_IO(a, b) OSAddAtomic64((int64_t)(a), (int64_t *)&(b));
95 typedef uint32_t pending_io_t
;
96 #define INCR_PENDING_IO(a, b) OSAddAtomic((int32_t)(a), (int32_t *)&(b));
101 * Structure per mounted file system. Each mounted file system has an
102 * array of operations and an instance record. The file systems are
103 * put on a doubly linked list.
105 TAILQ_HEAD(vnodelst
, vnode
);
108 TAILQ_ENTRY(mount
) mnt_list
; /* mount list */
109 int32_t mnt_count
; /* reference on the mount */
110 lck_mtx_t mnt_mlock
; /* mutex that protects mount point */
111 const struct vfsops
*mnt_op
; /* operations on fs */
112 struct vfstable
*mnt_vtable
; /* configuration info */
113 struct vnode
*mnt_vnodecovered
; /* vnode we mounted on */
114 struct vnodelst mnt_vnodelist
; /* list of vnodes this mount */
115 struct vnodelst mnt_workerqueue
; /* list of vnodes this mount */
116 struct vnodelst mnt_newvnodes
; /* list of vnodes this mount */
117 uint32_t mnt_flag
; /* flags */
118 uint32_t mnt_kern_flag
; /* kernel only flags */
119 uint32_t mnt_compound_ops
; /* Available compound operations */
120 uint32_t mnt_lflag
; /* mount life cycle flags */
121 uint32_t mnt_maxsymlinklen
; /* max size of short symlink */
122 struct vfsstatfs mnt_vfsstat
; /* cache of filesystem stats */
123 qaddr_t mnt_data
; /* private data */
124 /* Cached values of the IO constraints for the device */
125 uint32_t mnt_maxreadcnt
; /* Max. byte count for read */
126 uint32_t mnt_maxwritecnt
; /* Max. byte count for write */
127 uint32_t mnt_segreadcnt
; /* Max. segment count for read */
128 uint32_t mnt_segwritecnt
; /* Max. segment count for write */
129 uint32_t mnt_maxsegreadsize
; /* Max. segment read size */
130 uint32_t mnt_maxsegwritesize
; /* Max. segment write size */
131 uint32_t mnt_alignmentmask
; /* Mask of bits that aren't addressable via DMA */
132 uint32_t mnt_devblocksize
; /* the underlying device block size */
133 uint32_t mnt_ioqueue_depth
; /* the maxiumum number of commands a device can accept */
134 uint32_t mnt_ioscale
; /* scale the various throttles/limits imposed on the amount of I/O in flight */
135 uint32_t mnt_ioflags
; /* flags for underlying device */
136 uint32_t mnt_minsaturationbytecount
; /* if non-zero, mininum amount of writes (in bytes) needed to max out throughput */
137 pending_io_t mnt_pending_write_size
__attribute__((aligned(sizeof(pending_io_t
)))); /* byte count of pending writes */
138 pending_io_t mnt_pending_read_size
__attribute__((aligned(sizeof(pending_io_t
)))); /* byte count of pending reads */
139 struct timeval mnt_last_write_issued_timestamp
;
140 struct timeval mnt_last_write_completed_timestamp
;
141 int64_t mnt_max_swappin_available
;
143 lck_rw_t mnt_rwlock
; /* mutex readwrite lock */
144 lck_mtx_t mnt_renamelock
; /* mutex that serializes renames that change shape of tree */
145 vnode_t mnt_devvp
; /* the device mounted on for local file systems */
146 uint32_t mnt_devbsdunit
; /* the BSD unit number of the device */
147 uint64_t mnt_throttle_mask
; /* the throttle mask of what devices will be affected by I/O from this mnt */
148 void *mnt_throttle_info
; /* used by the throttle code */
149 int32_t mnt_crossref
; /* refernces to cover lookups crossing into mp */
150 int32_t mnt_iterref
; /* refernces to cover iterations; drained makes it -ve */
152 int32_t mnt_numtriggers
; /* num of trigger vnodes for this mount */
153 vfs_trigger_callback_t
*mnt_triggercallback
;
154 void *mnt_triggerdata
;
156 /* XXX 3762912 hack to support HFS filesystem 'owner' */
160 struct label
*mnt_mntlabel
; /* MAC mount label */
161 struct label
*mnt_fslabel
; /* MAC default fs label */
164 * cache the rootvp of the last mount point
165 * in the chain in the mount struct pointed
166 * to by the vnode sitting in '/'
167 * this cache is used to shortcircuit the
168 * mount chain traversal and allows us
169 * to traverse to the true underlying rootvp
170 * in 1 easy step inside of 'cache_lookup_path'
172 * make sure to validate against the cached vid
173 * in case the rootvp gets stolen away since
174 * we don't take an explicit long term reference
175 * on it when we mount it
177 vnode_t mnt_realrootvp
;
178 uint32_t mnt_realrootvp_vid
;
180 * bumped each time a mount or unmount
181 * occurs... its used to invalidate
182 * 'mnt_realrootvp' from the cache
184 uint32_t mnt_generation
;
186 * if 'MNTK_AUTH_CACHE_TIMEOUT' is
187 * set, then 'mnt_authcache_ttl' is
188 * the time-to-live for the per-vnode authentication cache
189 * on this mount... if zero, no cache is maintained...
190 * if 'MNTK_AUTH_CACHE_TIMEOUT' isn't set, its the
191 * time-to-live for the cached lookup right for
192 * volumes marked 'MNTK_AUTH_OPAQUE'.
194 int mnt_authcache_ttl
;
195 char fstypename_override
[MFSTYPENAMELEN
];
197 uint32_t mnt_iobufinuse
;
199 void *mnt_disk_conditioner_info
;
201 lck_mtx_t mnt_iter_lock
; /* mutex that protects iteration of vnodes */
205 * default number of seconds to keep cached lookup
206 * rights valid on mounts marked MNTK_AUTH_OPAQUE
208 #define CACHED_LOOKUP_RIGHT_TTL 2
213 #define MNT_IOFLAGS_FUA_SUPPORTED 0x00000001
214 #define MNT_IOFLAGS_UNMAP_SUPPORTED 0x00000002
215 #define MNT_IOFLAGS_IOSCHED_SUPPORTED 0x00000004
216 #define MNT_IOFLAGS_CSUNMAP_SUPPORTED 0x00000008
217 #define MNT_IOFLAGS_SWAPPIN_SUPPORTED 0x00000010
218 #define MNT_IOFLAGS_FUSION_DRIVE 0x00000020
219 #define MNT_IOFLAGS_PERIPHERAL_DRIVE 0x00000040 /* External: Attached directly to the system (USB,TBT,FW,etc.) */
222 * ioqueue depth for devices that don't report one
224 #define MNT_DEFAULT_IOQUEUE_DEPTH 32
227 * mnt_ioscale value for the given ioqueue depth
229 #define MNT_IOSCALE(ioqueue_depth) ((ioqueue_depth + (MNT_DEFAULT_IOQUEUE_DEPTH - 1)) / MNT_DEFAULT_IOQUEUE_DEPTH)
231 /* mount point to which dead vps point to */
232 extern struct mount
* dead_mountp
;
235 * Internal filesystem control flags stored in mnt_kern_flag.
237 * MNTK_UNMOUNT locks the mount entry so that name lookup cannot proceed
238 * past the mount point. This keeps the subtree stable during mounts
241 * Note: We are counting down on new bit assignments. This is
242 * because the bits here were broken out from the high bits
243 * of the mount flags.
245 #define MNTK_SYSTEM 0x00000040 /* Volume associated with system volume (do not allow unmount) */
246 #define MNTK_NOSWAP 0x00000080 /* swap files cannot be used on this mount */
247 #define MNTK_SWAP_MOUNT 0x00000100 /* we are swapping to this mount */
248 #define MNTK_DENY_READDIREXT 0x00000200 /* Deny Extended-style readdir's for this volume */
249 #define MNTK_PERMIT_UNMOUNT 0x00000400 /* Allow (non-forced) unmounts by UIDs other than the one that mounted the volume */
251 #define MNTK_TYPENAME_OVERRIDE 0x00000800 /* override the fstypename for statfs() */
252 #endif /* NFSCLIENT */
253 #define MNTK_KERNEL_MOUNT 0x00001000 /* mount came from kernel side */
254 #ifdef CONFIG_IMGSRC_ACCESS
255 #define MNTK_HAS_MOVED 0x00002000
256 #define MNTK_BACKS_ROOT 0x00004000
257 #endif /* CONFIG_IMGSRC_ACCESS */
258 #define MNTK_AUTH_CACHE_TTL 0x00008000 /* rights cache has TTL - TTL of 0 disables cache */
259 #define MNTK_PATH_FROM_ID 0x00010000 /* mounted file system supports id-to-path lookups */
260 #define MNTK_UNMOUNT_PREFLIGHT 0x00020000 /* mounted file system wants preflight check during unmount */
261 #define MNTK_NAMED_STREAMS 0x00040000 /* mounted file system supports Named Streams VNOPs */
262 #define MNTK_EXTENDED_ATTRS 0x00080000 /* mounted file system supports Extended Attributes VNOPs */
263 #define MNTK_LOCK_LOCAL 0x00100000 /* advisory locking is done above the VFS itself */
264 #define MNTK_VIRTUALDEV 0x00200000 /* mounted on a virtual device i.e. a disk image */
265 #define MNTK_ROOTDEV 0x00400000 /* this filesystem resides on the same device as the root */
266 #define MNTK_SSD 0x00800000 /* underlying device is of the solid state variety */
267 #define MNTK_UNMOUNT 0x01000000 /* unmount in progress */
268 #define MNTK_MWAIT 0x02000000 /* waiting for unmount to finish */
269 #define MNTK_WANTRDWR 0x04000000 /* upgrade to read/write requested */
271 #define MNT_REVEND 0x08000000 /* Reverse endian FS */
272 #endif /* REV_ENDIAN_FS */
273 #define MNTK_DIR_HARDLINKS 0x10000000 /* mounted file system supports directory hard links */
274 #define MNTK_AUTH_OPAQUE 0x20000000 /* authorisation decisions are not made locally */
275 #define MNTK_AUTH_OPAQUE_ACCESS 0x40000000 /* VNOP_ACCESS is reliable for remote auth */
276 #define MNTK_EXTENDED_SECURITY 0x80000000 /* extended security supported */
278 #define MNT_LNOTRESP 0x00000001 /* mount not responding */
279 #define MNT_LUNMOUNT 0x00000002 /* mount in unmount */
280 #define MNT_LFORCE 0x00000004 /* mount in forced unmount */
281 #define MNT_LDRAIN 0x00000008 /* mount in drain */
282 #define MNT_LITER 0x00000010 /* mount in iteration */
283 #define MNT_LNEWVN 0x00000020 /* mount has new vnodes created */
284 #define MNT_LWAIT 0x00000040 /* wait for unmount op */
285 #define MNT_LUNUSED 0x00000080 /* available flag bit, used to be MNT_LITERWAIT */
286 #define MNT_LDEAD 0x00000100 /* mount already unmounted*/
287 #define MNT_LNOSUB 0x00000200 /* submount - no recursion */
291 * Generic file handle
293 #define NFS_MAX_FH_SIZE NFSV4_MAX_FH_SIZE
294 #define NFSV4_MAX_FH_SIZE 128
295 #define NFSV3_MAX_FH_SIZE 64
296 #define NFSV2_MAX_FH_SIZE 32
298 unsigned int fh_len
; /* length of file handle */
299 unsigned char fh_data
[NFS_MAX_FH_SIZE
]; /* file handle value */
301 typedef struct fhandle fhandle_t
;
306 * Filesystem configuration information. One of these exists for each
307 * type of filesystem supported by the kernel. These are searched at
308 * mount time to identify the requested filesystem.
311 const struct vfsops
*vfc_vfsops
;/* filesystem operations vector */
312 char vfc_name
[MFSNAMELEN
]; /* filesystem type name */
313 int vfc_typenum
; /* historic filesystem type number */
314 int vfc_refcount
; /* number mounted of this type */
315 int vfc_flags
; /* permanent flags */
316 int (*vfc_mountroot
)(mount_t
, vnode_t
, vfs_context_t
); /* if != NULL, routine to mount root */
317 struct vfstable
*vfc_next
; /* next in list */
318 int32_t vfc_reserved1
;
319 int32_t vfc_reserved2
;
320 int vfc_vfsflags
; /* for optional types */
321 void * vfc_descptr
; /* desc table allocated address */
322 int vfc_descsize
; /* size allocated for desc table */
323 struct sysctl_oid
*vfc_sysctl
; /* dynamically registered sysctl node */
327 #define VFC_VFSLOCALARGS 0x002
328 #define VFC_VFSGENERICARGS 0x004
329 #define VFC_VFSNATIVEXATTR 0x010
330 #define VFC_VFSCANMOUNTROOT 0x020
331 #define VFC_VFSPREFLIGHT 0x040
332 #define VFC_VFSREADDIR_EXTENDED 0x080
333 #define VFC_VFS64BITREADY 0x100
334 #define VFC_VFSNOMACLABEL 0x1000
335 #define VFC_VFSVNOP_PAGEINV2 0x2000
336 #define VFC_VFSVNOP_PAGEOUTV2 0x4000
337 #define VFC_VFSVNOP_NOUPDATEID_RENAME 0x8000
338 #define VFC_VFSVNOP_SECLUDE_RENAME 0x10000
340 extern int maxvfstypenum
; /* highest defined filesystem type */
341 extern struct vfstable
*vfsconf
; /* head of list of filesystem types */
342 extern const int maxvfsslots
; /* Maximum statically allocated slots available to be used */
343 extern int numused_vfsslots
; /* number of statically allocated slots already used */
344 extern int numregistered_fses
; /* number of total registered filesystems */
346 /* the following two are xnu private */
347 struct vfstable
* vfstable_add(struct vfstable
*);
348 int vfstable_del(struct vfstable
*);
351 struct vfsmount_args
{
358 void * mnt_fsdata
; /* FS specific */
365 * LP64 *user* version of statfs structure.
366 * NOTE - must be kept in sync with struct statfs in mount.h
368 struct user64_statfs
{
369 short f_otype
; /* TEMPORARY SHADOW COPY OF f_type */
370 short f_oflags
; /* TEMPORARY SHADOW COPY OF f_flags */
371 user64_long_t f_bsize
; /* fundamental file system block size */
372 user64_long_t f_iosize
; /* optimal transfer block size */
373 user64_long_t f_blocks
; /* total data blocks in file system */
374 user64_long_t f_bfree
; /* free blocks in fs */
375 user64_long_t f_bavail
; /* free blocks avail to non-superuser */
376 user64_long_t f_files
; /* total file nodes in file system */
377 user64_long_t f_ffree
; /* free file nodes in fs */
378 fsid_t f_fsid
; /* file system id */
379 uid_t f_owner
; /* user that mounted the filesystem */
380 short f_reserved1
; /* spare for later */
381 short f_type
; /* type of filesystem */
382 user64_long_t f_flags
; /* copy of mount exported flags */
383 user64_long_t f_reserved2
[2]; /* reserved for future use */
384 char f_fstypename
[MFSNAMELEN
]; /* fs type name */
385 char f_mntonname
[MNAMELEN
]; /* directory on which mounted */
386 char f_mntfromname
[MNAMELEN
];/* mounted filesystem */
387 char f_reserved3
; /* For alignment */
388 user64_long_t f_reserved4
[4]; /* For future use */
392 * ILP32 *user* version of statfs structure.
393 * NOTE - must be kept in sync with struct statfs in mount.h
395 struct user32_statfs
{
396 short f_otype
; /* TEMPORARY SHADOW COPY OF f_type */
397 short f_oflags
; /* TEMPORARY SHADOW COPY OF f_flags */
398 user32_long_t f_bsize
; /* fundamental file system block size */
399 user32_long_t f_iosize
; /* optimal transfer block size */
400 user32_long_t f_blocks
; /* total data blocks in file system */
401 user32_long_t f_bfree
; /* free blocks in fs */
402 user32_long_t f_bavail
; /* free blocks avail to non-superuser */
403 user32_long_t f_files
; /* total file nodes in file system */
404 user32_long_t f_ffree
; /* free file nodes in fs */
405 fsid_t f_fsid
; /* file system id */
406 uid_t f_owner
; /* user that mounted the filesystem */
407 short f_reserved1
; /* spare for later */
408 short f_type
; /* type of filesystem */
409 user32_long_t f_flags
; /* copy of mount exported flags */
410 user32_long_t f_reserved2
[2]; /* reserved for future use */
411 char f_fstypename
[MFSNAMELEN
]; /* fs type name */
412 char f_mntonname
[MNAMELEN
]; /* directory on which mounted */
413 char f_mntfromname
[MNAMELEN
];/* mounted filesystem */
414 char f_reserved3
; /* For alignment */
415 user32_long_t f_reserved4
[4]; /* For future use */
419 * throttle I/Os are affected only by normal I/Os happening on the same spindle. Currently we use a 64-bit integer to
420 * represent what devices are affected, so we can handle at most 64 different spindles. Since
421 * throttled I/O is usually useful in non-server environment only, this number is enough in most cases.
423 #define LOWPRI_MAX_NUM_DEV 64
427 extern uint32_t mount_generation
;
428 extern TAILQ_HEAD(mntlist
, mount
) mountlist
;
429 void mount_list_lock(void);
430 void mount_list_unlock(void);
431 void mount_lock_init(mount_t
);
432 void mount_lock_destroy(mount_t
);
433 void mount_lock(mount_t
);
434 void mount_lock_spin(mount_t
);
435 void mount_unlock(mount_t
);
436 void mount_iterate_lock(mount_t
);
437 void mount_iterate_unlock(mount_t
);
438 void mount_lock_renames(mount_t
);
439 void mount_unlock_renames(mount_t
);
440 void mount_ref(mount_t
, int);
441 void mount_drop(mount_t
, int);
442 int mount_refdrain(mount_t
);
444 /* vfs_rootmountalloc should be kept as a private api */
445 errno_t
vfs_rootmountalloc(const char *, const char *, mount_t
*mpp
);
447 int vfs_mount_rosv_data(void);
448 int vfs_mount_vm(void);
450 int vfs_mountroot(void);
451 void vfs_unmountall(void);
452 int safedounmount(struct mount
*, int, vfs_context_t
);
453 int dounmount(struct mount
*, int, int, vfs_context_t
);
454 void dounmount_submounts(struct mount
*, int, vfs_context_t
);
456 /* xnu internal api */
457 void mount_dropcrossref(mount_t
, vnode_t
, int);
458 mount_t
mount_lookupby_volfsid(int, int);
459 mount_t
mount_list_lookupby_fsid(fsid_t
*, int, int);
460 int mount_list_add(mount_t
);
461 void mount_list_remove(mount_t
);
462 int mount_iterref(mount_t
, int);
463 int mount_isdrained(mount_t
, int);
464 void mount_iterdrop(mount_t
);
465 void mount_iterdrain(mount_t
);
466 void mount_iterreset(mount_t
);
468 /* These flags are used as flag bits in the `internal_flags` argument to mount_common */
469 /* Private NFS spi */
470 #define KERNEL_MOUNT_NOAUTH 0x01 /* Don't check the UID of the directory we are mounting on */
471 #define KERNEL_MOUNT_PERMIT_UNMOUNT 0x02 /* Allow (non-forced) unmounts by users other the one who mounted the volume */
472 /* used by snapshot mounting SPI */
473 #define KERNEL_MOUNT_SNAPSHOT 0x04 /* Mounting a snapshot */
474 #define KERNEL_MOUNT_DATAVOL 0x08 /* mount the data volume */
475 #define KERNEL_MOUNT_VMVOL 0x10 /* mount the VM volume */
478 #if NFSCLIENT || DEVFS || ROUTEFS
480 * NOTE: kernel_mount() does not force MNT_NOSUID, MNT_NOEXEC, or MNT_NODEC for non-privileged
481 * mounting credentials, as the mount(2) system call does.
483 int kernel_mount(char *, vnode_t
, vnode_t
, const char *, void *, size_t, int, uint32_t, vfs_context_t
);
484 boolean_t
vfs_iskernelmount(mount_t
);
487 /* Throttled I/O API. KPI/SPI is in systm.h. */
489 int throttle_get_io_policy(struct uthread
**ut
);
490 int throttle_get_passive_io_policy(struct uthread
**ut
);
491 void *throttle_info_update_by_mount(mount_t mp
);
492 void rethrottle_thread(uthread_t ut
);
495 /* throttled I/O helper function */
496 /* convert the lowest bit to a device index */
497 extern int num_trailing_0(uint64_t n
);
500 extern lck_mtx_t
* sync_mtx_lck
;
502 extern int sync_timeout_seconds
;
506 #endif /* !_SYS_MOUNT_INTERNAL_H_ */