1 /* 2 * Copyright (c) 2000-2021 Apple 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 * 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, 67 * Version 2.0. 68 */ 69 70 #ifndef _SYS_MOUNT_INTERNAL_H_ 71 #define _SYS_MOUNT_INTERNAL_H_ 72 73 #include <sys/appleapiopts.h> 74 #ifndef KERNEL 75 #include <sys/ucred.h> 76 #else 77 #include <sys/kernel_types.h> 78 #include <sys/namei.h> 79 #endif 80 #include <sys/_types/_graftdmg_un.h> 81 #include <sys/queue.h> 82 #include <sys/lock.h> 83 #include <net/radix.h> 84 #include <sys/socket.h> /* XXX for AF_MAX */ 85 #include <sys/vfs_context.h> /* XXX for AF_MAX */ 86 #include <sys/mount.h> 87 #include <sys/cdefs.h> 88 #include <sys/sysctl.h> 89 90 struct label; 91 92 #if defined(__i386__) || defined(__x86_64__) 93 typedef uint64_t pending_io_t; 94 #define INCR_PENDING_IO(a, b) OSAddAtomic64((int64_t)(a), (int64_t *)&(b)); 95 #else 96 typedef uint32_t pending_io_t; 97 #define INCR_PENDING_IO(a, b) OSAddAtomic((int32_t)(a), (int32_t *)&(b)); 98 #endif 99 100 101 /* 102 * Structure per mounted file system. Each mounted file system has an 103 * array of operations and an instance record. The file systems are 104 * put on a doubly linked list. 105 */ 106 TAILQ_HEAD(vnodelst, vnode); 107 108 struct mount { 109 TAILQ_ENTRY(mount) mnt_list; /* mount list */ 110 int32_t mnt_count; /* reference on the mount */ 111 lck_mtx_t mnt_mlock; /* mutex that protects mount point */ 112 const struct vfsops * XNU_PTRAUTH_SIGNED_PTR("mount.vfsops") mnt_op; /* operations on fs */ 113 struct vfstable * XNU_PTRAUTH_SIGNED_PTR("mount.mnt_vtable") mnt_vtable; /* configuration info */ 114 struct vnode * XNU_PTRAUTH_SIGNED_PTR("mount.mnt_vnodecovered") mnt_vnodecovered; /* vnode we mounted on */ 115 struct vnodelst mnt_vnodelist; /* list of vnodes this mount */ 116 struct vnodelst mnt_workerqueue; /* list of vnodes this mount */ 117 struct vnodelst mnt_newvnodes; /* list of vnodes this mount */ 118 uint32_t mnt_flag; /* flags */ 119 uint32_t mnt_kern_flag; /* kernel only flags. NOTE: See mnt_supl_kern_flags below! */ 120 uint32_t mnt_compound_ops; /* Available compound operations */ 121 uint32_t mnt_lflag; /* mount life cycle flags */ 122 uint32_t mnt_maxsymlinklen; /* max size of short symlink */ 123 struct vfsstatfs mnt_vfsstat; /* cache of filesystem stats */ 124 qaddr_t mnt_data; /* private data */ 125 /* Cached values of the IO constraints for the device */ 126 uint32_t mnt_maxreadcnt; /* Max. byte count for read */ 127 uint32_t mnt_maxwritecnt; /* Max. byte count for write */ 128 uint32_t mnt_segreadcnt; /* Max. segment count for read */ 129 uint32_t mnt_segwritecnt; /* Max. segment count for write */ 130 uint32_t mnt_maxsegreadsize; /* Max. segment read size */ 131 uint32_t mnt_maxsegwritesize; /* Max. segment write size */ 132 uint32_t mnt_alignmentmask; /* Mask of bits that aren't addressable via DMA */ 133 uint32_t mnt_devblocksize; /* the underlying device block size */ 134 uint32_t mnt_ioqueue_depth; /* the maxiumum number of commands a device can accept */ 135 uint32_t mnt_ioscale; /* scale the various throttles/limits imposed on the amount of I/O in flight */ 136 uint32_t mnt_ioflags; /* flags for underlying device */ 137 uint32_t mnt_minsaturationbytecount; /* if non-zero, mininum amount of writes (in bytes) needed to max out throughput */ 138 pending_io_t mnt_pending_write_size __attribute__((aligned(sizeof(pending_io_t)))); /* byte count of pending writes */ 139 pending_io_t mnt_pending_read_size __attribute__((aligned(sizeof(pending_io_t)))); /* byte count of pending reads */ 140 struct timeval mnt_last_write_issued_timestamp; 141 struct timeval mnt_last_write_completed_timestamp; 142 int64_t mnt_max_swappin_available; 143 144 lck_rw_t mnt_rwlock; /* mutex readwrite lock */ 145 lck_mtx_t mnt_renamelock; /* mutex that serializes renames that change shape of tree */ 146 vnode_t mnt_devvp; /* the device mounted on for local file systems */ 147 uint32_t mnt_devbsdunit; /* the BSD unit number of the device */ 148 uint64_t mnt_throttle_mask; /* the throttle mask of what devices will be affected by I/O from this mnt */ 149 void *mnt_throttle_info; /* used by the throttle code */ 150 int32_t mnt_crossref; /* refernces to cover lookups crossing into mp */ 151 int32_t mnt_iterref; /* refernces to cover iterations; drained makes it -ve */ 152 #if CONFIG_TRIGGERS 153 int32_t mnt_numtriggers; /* num of trigger vnodes for this mount */ 154 vfs_trigger_callback_t *mnt_triggercallback; 155 void *mnt_triggerdata; 156 #endif 157 /* XXX 3762912 hack to support HFS filesystem 'owner' */ 158 uid_t mnt_fsowner; 159 gid_t mnt_fsgroup; 160 161 struct label *mnt_mntlabel; /* MAC mount label */ 162 163 /* 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' 171 * 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 176 */ 177 vnode_t mnt_realrootvp; 178 uint32_t mnt_realrootvp_vid; 179 /* 180 * bumped each time a mount or unmount 181 * occurs... its used to invalidate 182 * 'mnt_realrootvp' from the cache 183 */ 184 uint32_t mnt_generation; 185 /* 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'. 193 */ 194 int mnt_authcache_ttl; 195 char fstypename_override[MFSTYPENAMELEN]; 196 197 uint32_t mnt_iobufinuse; 198 199 void *mnt_disk_conditioner_info; 200 201 lck_mtx_t mnt_iter_lock; /* mutex that protects iteration of vnodes */ 202 203 uint64_t mnt_mount_id; /* system-wide unique mount ID */ 204 uint32_t mnt_supl_kern_flag; /* Supplemental kernel-only mount flags */ 205 }; 206 207 /* 208 * default number of seconds to keep cached lookup 209 * rights valid on mounts marked MNTK_AUTH_OPAQUE 210 */ 211 #define CACHED_LOOKUP_RIGHT_TTL 2 212 213 /* 214 * ioflags 215 */ 216 #define MNT_IOFLAGS_FUA_SUPPORTED 0x00000001 217 #define MNT_IOFLAGS_UNMAP_SUPPORTED 0x00000002 218 #define MNT_IOFLAGS_IOSCHED_SUPPORTED 0x00000004 219 #define MNT_IOFLAGS_CSUNMAP_SUPPORTED 0x00000008 220 #define MNT_IOFLAGS_SWAPPIN_SUPPORTED 0x00000010 221 #define MNT_IOFLAGS_FUSION_DRIVE 0x00000020 222 #define MNT_IOFLAGS_PERIPHERAL_DRIVE 0x00000040 /* External: Attached directly to the system (USB,TBT,FW,etc.) */ 223 224 /* 225 * ioqueue depth for devices that don't report one 226 */ 227 #define MNT_DEFAULT_IOQUEUE_DEPTH 32 228 229 /* 230 * mnt_ioscale value for the given ioqueue depth 231 */ 232 #define MNT_IOSCALE(ioqueue_depth) ((ioqueue_depth + (MNT_DEFAULT_IOQUEUE_DEPTH - 1)) / MNT_DEFAULT_IOQUEUE_DEPTH) 233 234 /* mount point to which dead vps point to */ 235 extern struct mount * const dead_mountp; 236 237 /* 238 * Internal filesystem control flags stored in mnt_kern_flag. 239 * 240 * MNTK_UNMOUNT locks the mount entry so that name lookup cannot proceed 241 * past the mount point. This keeps the subtree stable during mounts 242 * and unmounts. 243 * 244 * Note: We are counting down on new bit assignments. This is 245 * because the bits here were broken out from the high bits 246 * of the mount flags. 247 */ 248 #define MNTK_FSKIT 0x00000020 /* Volume is a FSKit mount */ 249 #define MNTK_SYSTEM 0x00000040 /* Volume associated with system volume (do not allow unmount) */ 250 #define MNTK_NOSWAP 0x00000080 /* swap files cannot be used on this mount */ 251 #define MNTK_SWAP_MOUNT 0x00000100 /* we are swapping to this mount */ 252 #define MNTK_DENY_READDIREXT 0x00000200 /* Deny Extended-style readdir's for this volume */ 253 #define MNTK_PERMIT_UNMOUNT 0x00000400 /* Allow (non-forced) unmounts by UIDs other than the one that mounted the volume */ 254 #define MNTK_TYPENAME_OVERRIDE 0x00000800 /* override the fstypename for statfs() */ 255 #define MNTK_KERNEL_MOUNT 0x00001000 /* mount came from kernel side */ 256 #ifdef CONFIG_IMGSRC_ACCESS 257 #define MNTK_HAS_MOVED 0x00002000 258 #endif /* CONFIG_IMGSRC_ACCESS */ 259 #define MNTK_BACKS_ROOT 0x00004000 /* mount contains a disk image backing the root filesystem - therefore it mustn't be unmounted */ 260 #define MNTK_AUTH_CACHE_TTL 0x00008000 /* rights cache has TTL - TTL of 0 disables cache */ 261 #define MNTK_PATH_FROM_ID 0x00010000 /* mounted file system supports id-to-path lookups */ 262 #define MNTK_UNMOUNT_PREFLIGHT 0x00020000 /* mounted file system wants preflight check during unmount */ 263 #define MNTK_NAMED_STREAMS 0x00040000 /* mounted file system supports Named Streams VNOPs */ 264 #define MNTK_EXTENDED_ATTRS 0x00080000 /* mounted file system supports Extended Attributes VNOPs */ 265 #define MNTK_LOCK_LOCAL 0x00100000 /* advisory locking is done above the VFS itself */ 266 #define MNTK_VIRTUALDEV 0x00200000 /* mounted on a virtual device i.e. a disk image */ 267 #define MNTK_ROOTDEV 0x00400000 /* this filesystem resides on the same device as the root - appears unused as of 2020 */ 268 #define MNTK_SSD 0x00800000 /* underlying device is of the solid state variety */ 269 #define MNTK_UNMOUNT 0x01000000 /* unmount in progress */ 270 #define MNTK_MWAIT 0x02000000 /* waiting for unmount to finish - appears unused as of 2020 */ 271 #define MNTK_WANTRDWR 0x04000000 /* upgrade to read/write requested */ 272 #define MNTK_SYSTEMDATA 0x08000000 /* volume is a Data volume tightly linked with System root volume. Firmlinks, etc */ 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 */ 277 278 279 /* 280 * Internal supplemental FS control flags stored in mnt_supl_kern_flag 281 * 282 * NOTE: The 32 bits in the above-mentioned 32bit flag word (mnt_kern_flag) have been 283 * exhausted, so this is intended as a supplement. 284 */ 285 #define MNTK_SUPL_BASESYSTEM 0x00000001 286 #define MNTK_SUPL_USE_FULLSYNC 0x00000002 287 288 /* 289 * Mount Lifecycle Flags (stored in mnt_lflag) 290 */ 291 #define MNT_LNOTRESP 0x00000001 /* mount not responding */ 292 #define MNT_LUNMOUNT 0x00000002 /* mount in unmount */ 293 #define MNT_LFORCE 0x00000004 /* mount in forced unmount */ 294 #define MNT_LDRAIN 0x00000008 /* mount in drain */ 295 #define MNT_LITER 0x00000010 /* mount in iteration */ 296 #define MNT_LNEWVN 0x00000020 /* mount has new vnodes created */ 297 #define MNT_LWAIT 0x00000040 /* wait for unmount op */ 298 #define MNT_LMOUNT 0x00000080 /* not finished mounting */ 299 #define MNT_LDEAD 0x00000100 /* mount already unmounted*/ 300 #define MNT_LNOSUB 0x00000200 /* submount - no recursion */ 301 302 /* 303 * Filesystem configuration information. One of these exists for each 304 * type of filesystem supported by the kernel. These are searched at 305 * mount time to identify the requested filesystem. 306 */ 307 struct vfstable { 308 const struct vfsops *vfc_vfsops;/* filesystem operations vector */ 309 char vfc_name[MFSNAMELEN]; /* filesystem type name */ 310 int vfc_typenum; /* historic filesystem type number */ 311 int vfc_refcount; /* number mounted of this type */ 312 int vfc_flags; /* permanent flags */ 313 int (*vfc_mountroot)(mount_t, vnode_t, vfs_context_t); /* if != NULL, routine to mount root */ 314 struct vfstable *vfc_next; /* next in list */ 315 int32_t vfc_reserved1; 316 int32_t vfc_reserved2; 317 int vfc_vfsflags; /* for optional types */ 318 void *vfc_descptr; /* desc table allocated address */ 319 uint32_t vfc_descsize; /* number of elements in desc table */ 320 struct sysctl_oid *vfc_sysctl; /* dynamically registered sysctl node */ 321 }; 322 323 /* vfc_vfsflags: */ 324 #define VFC_VFSLOCALARGS 0x002 325 #define VFC_VFSGENERICARGS 0x004 326 #define VFC_VFSNATIVEXATTR 0x010 327 #define VFC_VFSCANMOUNTROOT 0x020 328 #define VFC_VFSPREFLIGHT 0x040 329 #define VFC_VFSREADDIR_EXTENDED 0x080 330 #define VFC_VFS64BITREADY 0x100 331 #define VFC_VFSNOMACLABEL 0x1000 332 #define VFC_VFSVNOP_PAGEINV2 0x2000 333 #define VFC_VFSVNOP_PAGEOUTV2 0x4000 334 #define VFC_VFSVNOP_NOUPDATEID_RENAME 0x8000 335 #define VFC_VFSVNOP_SECLUDE_RENAME 0x10000 336 337 extern int maxvfstypenum; /* highest defined filesystem type */ 338 extern struct vfstable *vfsconf; /* head of list of filesystem types */ 339 extern const int maxvfsslots; /* Maximum statically allocated slots available to be used */ 340 extern int numused_vfsslots; /* number of statically allocated slots already used */ 341 extern int numregistered_fses; /* number of total registered filesystems */ 342 343 /* the following two are xnu private */ 344 struct vfstable * vfstable_add(struct vfstable *); 345 int vfstable_del(struct vfstable *); 346 347 348 struct vfsmount_args { 349 union { 350 struct { 351 char * mnt_fspec; 352 void * mnt_fsdata; 353 } mnt_localfs_args; 354 struct { 355 void * mnt_fsdata; /* FS specific */ 356 } mnt_remotefs_args; 357 } mountfs_args; 358 }; 359 360 361 /* 362 * LP64 *user* version of statfs structure. 363 * NOTE - must be kept in sync with struct statfs in mount.h 364 */ 365 struct user64_statfs { 366 short f_otype; /* TEMPORARY SHADOW COPY OF f_type */ 367 short f_oflags; /* TEMPORARY SHADOW COPY OF f_flags */ 368 user64_long_t f_bsize; /* fundamental file system block size */ 369 user64_long_t f_iosize; /* optimal transfer block size */ 370 user64_long_t f_blocks; /* total data blocks in file system */ 371 user64_long_t f_bfree; /* free blocks in fs */ 372 user64_long_t f_bavail; /* free blocks avail to non-superuser */ 373 user64_long_t f_files; /* total file nodes in file system */ 374 user64_long_t f_ffree; /* free file nodes in fs */ 375 fsid_t f_fsid; /* file system id */ 376 uid_t f_owner; /* user that mounted the filesystem */ 377 short f_reserved1; /* spare for later */ 378 short f_type; /* type of filesystem */ 379 user64_long_t f_flags; /* copy of mount exported flags */ 380 user64_long_t f_reserved2[2]; /* reserved for future use */ 381 char f_fstypename[MFSNAMELEN]; /* fs type name */ 382 char f_mntonname[MNAMELEN]; /* directory on which mounted */ 383 char f_mntfromname[MNAMELEN];/* mounted filesystem */ 384 char f_reserved3; /* For alignment */ 385 user64_long_t f_reserved4[4]; /* For future use */ 386 }; 387 388 /* 389 * ILP32 *user* version of statfs structure. 390 * NOTE - must be kept in sync with struct statfs in mount.h 391 */ 392 struct user32_statfs { 393 short f_otype; /* TEMPORARY SHADOW COPY OF f_type */ 394 short f_oflags; /* TEMPORARY SHADOW COPY OF f_flags */ 395 user32_long_t f_bsize; /* fundamental file system block size */ 396 user32_long_t f_iosize; /* optimal transfer block size */ 397 user32_long_t f_blocks; /* total data blocks in file system */ 398 user32_long_t f_bfree; /* free blocks in fs */ 399 user32_long_t f_bavail; /* free blocks avail to non-superuser */ 400 user32_long_t f_files; /* total file nodes in file system */ 401 user32_long_t f_ffree; /* free file nodes in fs */ 402 fsid_t f_fsid; /* file system id */ 403 uid_t f_owner; /* user that mounted the filesystem */ 404 short f_reserved1; /* spare for later */ 405 short f_type; /* type of filesystem */ 406 user32_long_t f_flags; /* copy of mount exported flags */ 407 user32_long_t f_reserved2[2]; /* reserved for future use */ 408 char f_fstypename[MFSNAMELEN]; /* fs type name */ 409 char f_mntonname[MNAMELEN]; /* directory on which mounted */ 410 char f_mntfromname[MNAMELEN];/* mounted filesystem */ 411 char f_reserved3; /* For alignment */ 412 user32_long_t f_reserved4[4]; /* For future use */ 413 }; 414 415 /* 416 * throttle I/Os are affected only by normal I/Os happening on the same spindle. Currently we use a 64-bit integer to 417 * represent what devices are affected, so we can handle at most 64 different spindles. Since 418 * throttled I/O is usually useful in non-server environment only, this number is enough in most cases. 419 */ 420 #define LOWPRI_MAX_NUM_DEV 64 421 422 __BEGIN_DECLS 423 424 extern uint32_t mount_generation; 425 extern TAILQ_HEAD(mntlist, mount) mountlist; 426 void mount_list_lock(void); 427 void mount_list_unlock(void); 428 void mount_lock_init(mount_t); 429 void mount_lock_destroy(mount_t); 430 void mount_lock(mount_t); 431 void mount_lock_spin(mount_t); 432 void mount_unlock(mount_t); 433 void mount_iterate_lock(mount_t); 434 void mount_iterate_unlock(mount_t); 435 void mount_lock_renames(mount_t); 436 void mount_unlock_renames(mount_t); 437 void mount_ref(mount_t, int); 438 void mount_drop(mount_t, int); 439 int mount_refdrain(mount_t); 440 441 /* vfs_rootmountalloc should be kept as a private api */ 442 errno_t vfs_rootmountalloc(const char *, const char *, mount_t *mpp); 443 444 int vfs_mount_recovery(void); 445 446 typedef uint32_t vfs_switch_root_flags_t; 447 #define VFSSR_VIRTUALDEV_PROHIBITED 0x01 /* Not allowed to pivot into virtual devices (disk images). 448 * This is really just because we don't have a great way to find 449 * the filesystem that backs the image in order to set 450 * MNTK_BACKS_ROOT on it, which would prevent even forced-unmounts. 451 * Also, lots of disk images are backed by userspace processes, 452 * which also seems like a bad idea for the root filesystem. */ 453 454 int vfs_switch_root(const char *, const char *, vfs_switch_root_flags_t); 455 456 int vfs_mountroot(void); 457 void vfs_unmountall(int only_non_system); 458 int safedounmount(struct mount *, int, vfs_context_t); 459 int dounmount(struct mount *, int, int, vfs_context_t); 460 void dounmount_submounts(struct mount *, int, vfs_context_t); 461 int vfs_setmounting(vnode_t); 462 void vfs_clearmounting(vnode_t); 463 void vfs_setmountedon(vnode_t); 464 465 /* xnu internal api */ 466 void mount_dropcrossref(mount_t, vnode_t, int); 467 mount_t mount_lookupby_volfsid(int, int); 468 mount_t mount_list_lookupby_fsid(fsid_t *, int, int); 469 int mount_list_add(mount_t); 470 void mount_list_remove(mount_t); 471 int mount_iterref(mount_t, int); 472 int mount_isdrained(mount_t, int); 473 void mount_iterdrop(mount_t); 474 void mount_iterdrain(mount_t); 475 void mount_iterreset(mount_t); 476 477 /* These flags are used as flag bits in the `internal_flags` argument to mount_common */ 478 /* Private NFS spi */ 479 #define KERNEL_MOUNT_NOAUTH 0x01 /* Don't check the UID of the directory we are mounting on */ 480 #define KERNEL_MOUNT_PERMIT_UNMOUNT 0x02 /* Allow (non-forced) unmounts by users other the one who mounted the volume */ 481 /* used by snapshot mounting SPI */ 482 #define KERNEL_MOUNT_SNAPSHOT 0x04 /* Mounting a snapshot */ 483 #define KERNEL_MOUNT_DATAVOL 0x08 /* mount the data volume */ 484 #define KERNEL_MOUNT_VMVOL 0x10 /* mount the VM volume */ 485 #define KERNEL_MOUNT_PREBOOTVOL 0x20 /* mount the Preboot volume */ 486 #define KERNEL_MOUNT_RECOVERYVOL 0x40 /* mount the Recovery volume */ 487 #define KERNEL_MOUNT_BASESYSTEMROOT 0x80 /* mount a base root volume "instead of" the full root volume (only used during bsd_init) */ 488 #define KERNEL_MOUNT_DEVFS 0x100 /* kernel startup mount of devfs */ 489 #define KERNEL_MOUNT_FMOUNT 0x200 /* is fmount() system call */ 490 #define KERNEL_MOUNT_KMOUNT 0x400 /* is kernel_mount() call */ 491 492 /* mask for checking if any of the "mount volume by role" flags are set */ 493 #define KERNEL_MOUNT_VOLBYROLE_MASK (KERNEL_MOUNT_DATAVOL | KERNEL_MOUNT_VMVOL | KERNEL_MOUNT_PREBOOTVOL | KERNEL_MOUNT_RECOVERYVOL) 494 495 /* mask for sanitizing inputs to kernel_mount() */ 496 #define KERNEL_MOUNT_SANITIZE_MASK (~(KERNEL_MOUNT_FMOUNT)) 497 498 /* 499 * NOTE: kernel_mount() does not force MNT_NOSUID, MNT_NOEXEC, or MNT_NODEC for non-privileged 500 * mounting credentials, as the mount(2) system call does. 501 */ 502 int kernel_mount(const char *, vnode_t, vnode_t, const char *, void *, size_t, int, uint32_t, vfs_context_t); 503 504 /* Throttled I/O API. KPI/SPI is in systm.h. */ 505 506 int throttle_get_io_policy(struct uthread **ut); 507 int throttle_get_passive_io_policy(struct uthread **ut); 508 void *throttle_info_update_by_mount(mount_t mp); 509 void rethrottle_thread(uthread_t ut); 510 511 512 /* throttled I/O helper function */ 513 /* convert the lowest bit to a device index */ 514 extern int num_trailing_0(uint64_t n); 515 516 /* sync lock */ 517 extern int sync_timeout_seconds; 518 519 KALLOC_TYPE_DECLARE(mount_zone); 520 521 __END_DECLS 522 523 #endif /* !_SYS_MOUNT_INTERNAL_H_ */ 524