1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22 /*
23 * Copyright (c) 1988, 2010, Oracle and/or its affiliates. All rights reserved.
24 * Copyright 2016 Joyent, Inc.
25 * Copyright 2016 Toomas Soome <tsoome@me.com>
26 * Copyright (c) 2016, 2017 by Delphix. All rights reserved.
27 * Copyright 2016 Nexenta Systems, Inc.
28 * Copyright 2017 RackTop Systems.
29 */
30
31 /* Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */
32 /* All Rights Reserved */
33
34 /*
35 * University Copyright- Copyright (c) 1982, 1986, 1988
36 * The Regents of the University of California
37 * All Rights Reserved
38 *
39 * University Acknowledgment- Portions of this document are derived from
40 * software developed by the University of California, Berkeley, and its
41 * contributors.
42 */
43
44 #include <sys/types.h>
45 #include <sys/t_lock.h>
46 #include <sys/param.h>
47 #include <sys/errno.h>
48 #include <sys/user.h>
49 #include <sys/fstyp.h>
50 #include <sys/kmem.h>
51 #include <sys/systm.h>
52 #include <sys/proc.h>
53 #include <sys/mount.h>
54 #include <sys/vfs.h>
55 #include <sys/vfs_opreg.h>
56 #include <sys/fem.h>
57 #include <sys/mntent.h>
58 #include <sys/stat.h>
59 #include <sys/statvfs.h>
60 #include <sys/statfs.h>
61 #include <sys/cred.h>
62 #include <sys/vnode.h>
63 #include <sys/rwstlock.h>
64 #include <sys/dnlc.h>
65 #include <sys/file.h>
66 #include <sys/time.h>
67 #include <sys/atomic.h>
68 #include <sys/cmn_err.h>
69 #include <sys/buf.h>
70 #include <sys/swap.h>
71 #include <sys/debug.h>
72 #include <sys/vnode.h>
73 #include <sys/modctl.h>
74 #include <sys/ddi.h>
75 #include <sys/pathname.h>
76 #include <sys/bootconf.h>
77 #include <sys/dumphdr.h>
78 #include <sys/dc_ki.h>
79 #include <sys/poll.h>
80 #include <sys/sunddi.h>
81 #include <sys/sysmacros.h>
82 #include <sys/zone.h>
83 #include <sys/policy.h>
84 #include <sys/ctfs.h>
85 #include <sys/objfs.h>
86 #include <sys/console.h>
87 #include <sys/reboot.h>
88 #include <sys/attr.h>
89 #include <sys/zio.h>
90 #include <sys/spa.h>
91 #include <sys/lofi.h>
92 #include <sys/bootprops.h>
93
94 #include <vm/page.h>
95
96 #include <fs/fs_subr.h>
97 /* Private interfaces to create vopstats-related data structures */
98 extern void initialize_vopstats(vopstats_t *);
99 extern vopstats_t *get_fstype_vopstats(struct vfs *, struct vfssw *);
100 extern vsk_anchor_t *get_vskstat_anchor(struct vfs *);
101
102 static void vfs_clearmntopt_nolock(mntopts_t *, const char *, int);
103 static void vfs_setmntopt_nolock(mntopts_t *, const char *,
104 const char *, int, int);
105 static int vfs_optionisset_nolock(const mntopts_t *, const char *, char **);
106 static void vfs_freemnttab(struct vfs *);
107 static void vfs_freeopt(mntopt_t *);
108 static void vfs_swapopttbl_nolock(mntopts_t *, mntopts_t *);
109 static void vfs_swapopttbl(mntopts_t *, mntopts_t *);
110 static void vfs_copyopttbl_extend(const mntopts_t *, mntopts_t *, int);
111 static void vfs_createopttbl_extend(mntopts_t *, const char *,
112 const mntopts_t *);
113 static char **vfs_copycancelopt_extend(char **const, int);
114 static void vfs_freecancelopt(char **);
115 static void getrootfs(char **, char **);
116 static int getmacpath(dev_info_t *, void *);
117 static void vfs_mnttabvp_setup(void);
118
119 struct ipmnt {
120 struct ipmnt *mip_next;
121 dev_t mip_dev;
122 struct vfs *mip_vfsp;
123 };
124
125 static kmutex_t vfs_miplist_mutex;
126 static struct ipmnt *vfs_miplist = NULL;
127 static struct ipmnt *vfs_miplist_end = NULL;
128
129 static kmem_cache_t *vfs_cache; /* Pointer to VFS kmem cache */
130
131 /*
132 * VFS global data.
133 */
134 vnode_t *rootdir; /* pointer to root inode vnode. */
135 vnode_t *devicesdir; /* pointer to inode of devices root */
136 vnode_t *devdir; /* pointer to inode of dev root */
137
138 char *server_rootpath; /* root path for diskless clients */
139 char *server_hostname; /* hostname of diskless server */
140
141 static struct vfs root;
142 static struct vfs devices;
143 static struct vfs dev;
144 struct vfs *rootvfs = &root; /* pointer to root vfs; head of VFS list. */
145 rvfs_t *rvfs_list; /* array of vfs ptrs for vfs hash list */
146 int vfshsz = 512; /* # of heads/locks in vfs hash arrays */
147 /* must be power of 2! */
148 timespec_t vfs_mnttab_ctime; /* mnttab created time */
149 timespec_t vfs_mnttab_mtime; /* mnttab last modified time */
150 char *vfs_dummyfstype = "\0";
151 struct pollhead vfs_pollhd; /* for mnttab pollers */
152 struct vnode *vfs_mntdummyvp; /* to fake mnttab read/write for file events */
153 int mntfstype; /* will be set once mnt fs is mounted */
154
155 /*
156 * Table for generic options recognized in the VFS layer and acted
157 * on at this level before parsing file system specific options.
158 * The nosuid option is stronger than any of the devices and setuid
159 * options, so those are canceled when nosuid is seen.
160 *
161 * All options which are added here need to be added to the
162 * list of standard options in usr/src/cmd/fs.d/fslib.c as well.
163 */
164 /*
165 * VFS Mount options table
166 */
167 static char *ro_cancel[] = { MNTOPT_RW, NULL };
168 static char *rw_cancel[] = { MNTOPT_RO, NULL };
169 static char *suid_cancel[] = { MNTOPT_NOSUID, NULL };
170 static char *nosuid_cancel[] = { MNTOPT_SUID, MNTOPT_DEVICES, MNTOPT_NODEVICES,
171 MNTOPT_NOSETUID, MNTOPT_SETUID, NULL };
172 static char *devices_cancel[] = { MNTOPT_NODEVICES, NULL };
173 static char *nodevices_cancel[] = { MNTOPT_DEVICES, NULL };
174 static char *setuid_cancel[] = { MNTOPT_NOSETUID, NULL };
175 static char *nosetuid_cancel[] = { MNTOPT_SETUID, NULL };
176 static char *nbmand_cancel[] = { MNTOPT_NONBMAND, NULL };
177 static char *nonbmand_cancel[] = { MNTOPT_NBMAND, NULL };
178 static char *exec_cancel[] = { MNTOPT_NOEXEC, NULL };
179 static char *noexec_cancel[] = { MNTOPT_EXEC, NULL };
180
181 static const mntopt_t mntopts[] = {
182 /*
183 * option name cancel options default arg flags
184 */
185 { MNTOPT_REMOUNT, NULL, NULL,
186 MO_NODISPLAY, (void *)0 },
187 { MNTOPT_RO, ro_cancel, NULL, 0,
188 (void *)0 },
189 { MNTOPT_RW, rw_cancel, NULL, 0,
190 (void *)0 },
191 { MNTOPT_SUID, suid_cancel, NULL, 0,
192 (void *)0 },
193 { MNTOPT_NOSUID, nosuid_cancel, NULL, 0,
194 (void *)0 },
195 { MNTOPT_DEVICES, devices_cancel, NULL, 0,
196 (void *)0 },
197 { MNTOPT_NODEVICES, nodevices_cancel, NULL, 0,
198 (void *)0 },
199 { MNTOPT_SETUID, setuid_cancel, NULL, 0,
200 (void *)0 },
201 { MNTOPT_NOSETUID, nosetuid_cancel, NULL, 0,
202 (void *)0 },
203 { MNTOPT_NBMAND, nbmand_cancel, NULL, 0,
204 (void *)0 },
205 { MNTOPT_NONBMAND, nonbmand_cancel, NULL, 0,
206 (void *)0 },
207 { MNTOPT_EXEC, exec_cancel, NULL, 0,
208 (void *)0 },
209 { MNTOPT_NOEXEC, noexec_cancel, NULL, 0,
210 (void *)0 },
211 };
212
213 const mntopts_t vfs_mntopts = {
214 sizeof (mntopts) / sizeof (mntopt_t),
215 (mntopt_t *)&mntopts[0]
216 };
217
218 /*
219 * File system operation dispatch functions.
220 */
221
222 int
223 fsop_mount(vfs_t *vfsp, vnode_t *mvp, struct mounta *uap, cred_t *cr)
224 {
225 return (*(vfsp)->vfs_op->vfs_mount)(vfsp, mvp, uap, cr);
226 }
227
228 int
229 fsop_unmount(vfs_t *vfsp, int flag, cred_t *cr)
230 {
231 return (*(vfsp)->vfs_op->vfs_unmount)(vfsp, flag, cr);
232 }
233
234 int
235 fsop_root(vfs_t *vfsp, vnode_t **vpp)
236 {
237 refstr_t *mntpt;
238 int ret = (*(vfsp)->vfs_op->vfs_root)(vfsp, vpp);
239 /*
240 * Make sure this root has a path. With lofs, it is possible to have
241 * a NULL mountpoint.
242 */
243 if (ret == 0 && vfsp->vfs_mntpt != NULL &&
244 (*vpp)->v_path == vn_vpath_empty) {
245 const char *path;
246
247 mntpt = vfs_getmntpoint(vfsp);
248 path = refstr_value(mntpt);
249 vn_setpath_str(*vpp, path, strlen(path));
250 refstr_rele(mntpt);
251 }
252
253 return (ret);
254 }
255
256 int
257 fsop_statfs(vfs_t *vfsp, statvfs64_t *sp)
258 {
259 return (*(vfsp)->vfs_op->vfs_statvfs)(vfsp, sp);
260 }
261
262 int
263 fsop_sync(vfs_t *vfsp, short flag, cred_t *cr)
264 {
265 return (*(vfsp)->vfs_op->vfs_sync)(vfsp, flag, cr);
266 }
267
268 int
269 fsop_vget(vfs_t *vfsp, vnode_t **vpp, fid_t *fidp)
270 {
271 /*
272 * In order to handle system attribute fids in a manner
273 * transparent to the underlying fs, we embed the fid for
274 * the sysattr parent object in the sysattr fid and tack on
275 * some extra bytes that only the sysattr layer knows about.
276 *
277 * This guarantees that sysattr fids are larger than other fids
278 * for this vfs. If the vfs supports the sysattr view interface
279 * (as indicated by VFSFT_SYSATTR_VIEWS), we cannot have a size
280 * collision with XATTR_FIDSZ.
281 */
282 if (vfs_has_feature(vfsp, VFSFT_SYSATTR_VIEWS) &&
283 fidp->fid_len == XATTR_FIDSZ)
284 return (xattr_dir_vget(vfsp, vpp, fidp));
285
286 return (*(vfsp)->vfs_op->vfs_vget)(vfsp, vpp, fidp);
287 }
288
289 int
290 fsop_mountroot(vfs_t *vfsp, enum whymountroot reason)
291 {
292 return (*(vfsp)->vfs_op->vfs_mountroot)(vfsp, reason);
293 }
294
295 void
296 fsop_freefs(vfs_t *vfsp)
297 {
298 (*(vfsp)->vfs_op->vfs_freevfs)(vfsp);
299 }
300
301 int
302 fsop_vnstate(vfs_t *vfsp, vnode_t *vp, vntrans_t nstate)
303 {
304 return ((*(vfsp)->vfs_op->vfs_vnstate)(vfsp, vp, nstate));
305 }
306
307 int
308 fsop_sync_by_kind(int fstype, short flag, cred_t *cr)
309 {
310 ASSERT((fstype >= 0) && (fstype < nfstype));
311
312 if (ALLOCATED_VFSSW(&vfssw[fstype]) && VFS_INSTALLED(&vfssw[fstype]))
313 return (*vfssw[fstype].vsw_vfsops.vfs_sync) (NULL, flag, cr);
314 else
315 return (ENOTSUP);
316 }
317
318 /*
319 * File system initialization. vfs_setfsops() must be called from a file
320 * system's init routine.
321 */
322
323 static int
324 fs_copyfsops(const fs_operation_def_t *template, vfsops_t *actual,
325 int *unused_ops)
326 {
327 static const fs_operation_trans_def_t vfs_ops_table[] = {
328 VFSNAME_MOUNT, offsetof(vfsops_t, vfs_mount),
329 fs_nosys, fs_nosys,
330
331 VFSNAME_UNMOUNT, offsetof(vfsops_t, vfs_unmount),
332 fs_nosys, fs_nosys,
333
334 VFSNAME_ROOT, offsetof(vfsops_t, vfs_root),
335 fs_nosys, fs_nosys,
336
337 VFSNAME_STATVFS, offsetof(vfsops_t, vfs_statvfs),
338 fs_nosys, fs_nosys,
339
340 VFSNAME_SYNC, offsetof(vfsops_t, vfs_sync),
341 (fs_generic_func_p) fs_sync,
342 (fs_generic_func_p) fs_sync, /* No errors allowed */
343
344 VFSNAME_VGET, offsetof(vfsops_t, vfs_vget),
345 fs_nosys, fs_nosys,
346
347 VFSNAME_MOUNTROOT, offsetof(vfsops_t, vfs_mountroot),
348 fs_nosys, fs_nosys,
349
350 VFSNAME_FREEVFS, offsetof(vfsops_t, vfs_freevfs),
351 (fs_generic_func_p)fs_freevfs,
352 (fs_generic_func_p)fs_freevfs, /* Shouldn't fail */
353
354 VFSNAME_VNSTATE, offsetof(vfsops_t, vfs_vnstate),
355 (fs_generic_func_p)fs_nosys,
356 (fs_generic_func_p)fs_nosys,
357
358 NULL, 0, NULL, NULL
359 };
360
361 return (fs_build_vector(actual, unused_ops, vfs_ops_table, template));
362 }
363
364 void
365 zfs_boot_init(void)
366 {
367 if (strcmp(rootfs.bo_fstype, MNTTYPE_ZFS) == 0)
368 spa_boot_init();
369 }
370
371 int
372 vfs_setfsops(int fstype, const fs_operation_def_t *template, vfsops_t **actual)
373 {
374 int error;
375 int unused_ops;
376
377 /*
378 * Verify that fstype refers to a valid fs. Note that
379 * 0 is valid since it's used to set "stray" ops.
380 */
381 if ((fstype < 0) || (fstype >= nfstype))
382 return (EINVAL);
383
384 if (!ALLOCATED_VFSSW(&vfssw[fstype]))
385 return (EINVAL);
386
387 /* Set up the operations vector. */
388
389 error = fs_copyfsops(template, &vfssw[fstype].vsw_vfsops, &unused_ops);
390
391 if (error != 0)
392 return (error);
393
394 vfssw[fstype].vsw_flag |= VSW_INSTALLED;
395
396 if (actual != NULL)
397 *actual = &vfssw[fstype].vsw_vfsops;
398
399 #if DEBUG
400 if (unused_ops != 0)
401 cmn_err(CE_WARN, "vfs_setfsops: %s: %d operations supplied "
402 "but not used", vfssw[fstype].vsw_name, unused_ops);
403 #endif
404
405 return (0);
406 }
407
408 int
409 vfs_makefsops(const fs_operation_def_t *template, vfsops_t **actual)
410 {
411 int error;
412 int unused_ops;
413
414 *actual = (vfsops_t *)kmem_alloc(sizeof (vfsops_t), KM_SLEEP);
415
416 error = fs_copyfsops(template, *actual, &unused_ops);
417 if (error != 0) {
418 kmem_free(*actual, sizeof (vfsops_t));
419 *actual = NULL;
420 return (error);
421 }
422
423 return (0);
424 }
425
426 /*
427 * Free a vfsops structure created as a result of vfs_makefsops().
428 * NOTE: For a vfsops structure initialized by vfs_setfsops(), use
429 * vfs_freevfsops_by_type().
430 */
431 void
432 vfs_freevfsops(vfsops_t *vfsops)
433 {
434 kmem_free(vfsops, sizeof (vfsops_t));
435 }
436
437 /*
438 * Since the vfsops structure is part of the vfssw table and wasn't
439 * really allocated, we're not really freeing anything. We keep
440 * the name for consistency with vfs_freevfsops(). We do, however,
441 * need to take care of a little bookkeeping.
442 * NOTE: For a vfsops structure created by vfs_setfsops(), use
443 * vfs_freevfsops_by_type().
444 */
445 int
446 vfs_freevfsops_by_type(int fstype)
447 {
448
449 /* Verify that fstype refers to a loaded fs (and not fsid 0). */
450 if ((fstype <= 0) || (fstype >= nfstype))
451 return (EINVAL);
452
453 WLOCK_VFSSW();
454 if ((vfssw[fstype].vsw_flag & VSW_INSTALLED) == 0) {
455 WUNLOCK_VFSSW();
456 return (EINVAL);
457 }
458
459 vfssw[fstype].vsw_flag &= ~VSW_INSTALLED;
460 WUNLOCK_VFSSW();
461
462 return (0);
463 }
464
465 /* Support routines used to reference vfs_op */
466
467 /* Set the operations vector for a vfs */
468 void
469 vfs_setops(vfs_t *vfsp, vfsops_t *vfsops)
470 {
471 vfsops_t *op;
472
473 ASSERT(vfsp != NULL);
474 ASSERT(vfsops != NULL);
475
476 op = vfsp->vfs_op;
477 membar_consumer();
478 if (vfsp->vfs_femhead == NULL &&
479 atomic_cas_ptr(&vfsp->vfs_op, op, vfsops) == op) {
480 return;
481 }
482 fsem_setvfsops(vfsp, vfsops);
483 }
484
485 /* Retrieve the operations vector for a vfs */
486 vfsops_t *
487 vfs_getops(vfs_t *vfsp)
488 {
489 vfsops_t *op;
490
491 ASSERT(vfsp != NULL);
492
493 op = vfsp->vfs_op;
494 membar_consumer();
495 if (vfsp->vfs_femhead == NULL && op == vfsp->vfs_op) {
496 return (op);
497 } else {
498 return (fsem_getvfsops(vfsp));
499 }
500 }
501
502 /*
503 * Returns non-zero (1) if the vfsops matches that of the vfs.
504 * Returns zero (0) if not.
505 */
506 int
507 vfs_matchops(vfs_t *vfsp, vfsops_t *vfsops)
508 {
509 return (vfs_getops(vfsp) == vfsops);
510 }
511
512 /*
513 * Returns non-zero (1) if the file system has installed a non-default,
514 * non-error vfs_sync routine. Returns zero (0) otherwise.
515 */
516 int
517 vfs_can_sync(vfs_t *vfsp)
518 {
519 /* vfs_sync() routine is not the default/error function */
520 return (vfs_getops(vfsp)->vfs_sync != fs_sync);
521 }
522
523 /*
524 * Initialize a vfs structure.
525 */
526 void
527 vfs_init(vfs_t *vfsp, vfsops_t *op, void *data)
528 {
529 /* Other initialization has been moved to vfs_alloc() */
530 vfsp->vfs_count = 0;
531 vfsp->vfs_next = vfsp;
532 vfsp->vfs_prev = vfsp;
533 vfsp->vfs_zone_next = vfsp;
534 vfsp->vfs_zone_prev = vfsp;
535 vfsp->vfs_lofi_id = 0;
536 sema_init(&vfsp->vfs_reflock, 1, NULL, SEMA_DEFAULT, NULL);
537 vfsimpl_setup(vfsp);
538 vfsp->vfs_data = (data);
539 vfs_setops((vfsp), (op));
540 }
541
542 /*
543 * Allocate and initialize the vfs implementation private data
544 * structure, vfs_impl_t.
545 */
546 void
547 vfsimpl_setup(vfs_t *vfsp)
548 {
549 int i;
550
551 if (vfsp->vfs_implp != NULL) {
552 return;
553 }
554
555 vfsp->vfs_implp = kmem_alloc(sizeof (vfs_impl_t), KM_SLEEP);
556 /* Note that these are #define'd in vfs.h */
557 vfsp->vfs_vskap = NULL;
558 vfsp->vfs_fstypevsp = NULL;
559
560 /* Set size of counted array, then zero the array */
561 vfsp->vfs_featureset[0] = VFS_FEATURE_MAXSZ - 1;
562 for (i = 1; i < VFS_FEATURE_MAXSZ; i++) {
563 vfsp->vfs_featureset[i] = 0;
564 }
565 }
566
567 /*
568 * Release the vfs_impl_t structure, if it exists. Some unbundled
569 * filesystems may not use the newer version of vfs and thus
570 * would not contain this implementation private data structure.
571 */
572 void
573 vfsimpl_teardown(vfs_t *vfsp)
574 {
575 vfs_impl_t *vip = vfsp->vfs_implp;
576
577 if (vip == NULL)
578 return;
579
580 kmem_free(vfsp->vfs_implp, sizeof (vfs_impl_t));
581 vfsp->vfs_implp = NULL;
582 }
583
584 /*
585 * VFS system calls: mount, umount, syssync, statfs, fstatfs, statvfs,
586 * fstatvfs, and sysfs moved to common/syscall.
587 */
588
589 /*
590 * Update every mounted file system. We call the vfs_sync operation of
591 * each file system type, passing it a NULL vfsp to indicate that all
592 * mounted file systems of that type should be updated.
593 */
594 void
595 vfs_sync(int flag)
596 {
597 struct vfssw *vswp;
598 RLOCK_VFSSW();
599 for (vswp = &vfssw[1]; vswp < &vfssw[nfstype]; vswp++) {
600 if (ALLOCATED_VFSSW(vswp) && VFS_INSTALLED(vswp)) {
601 vfs_refvfssw(vswp);
602 RUNLOCK_VFSSW();
603 (void) (*vswp->vsw_vfsops.vfs_sync)(NULL, flag,
604 CRED());
605 vfs_unrefvfssw(vswp);
606 RLOCK_VFSSW();
607 }
608 }
609 RUNLOCK_VFSSW();
610 }
611
612 void
613 sync(void)
614 {
615 vfs_sync(0);
616 }
617
618 /*
619 * External routines.
620 */
621
622 krwlock_t vfssw_lock; /* lock accesses to vfssw */
623
624 /*
625 * Lock for accessing the vfs linked list. Initialized in vfs_mountroot(),
626 * but otherwise should be accessed only via vfs_list_lock() and
627 * vfs_list_unlock(). Also used to protect the timestamp for mods to the list.
628 */
629 static krwlock_t vfslist;
630
631 /*
632 * Mount devfs on /devices. This is done right after root is mounted
633 * to provide device access support for the system
634 */
635 static void
636 vfs_mountdevices(void)
637 {
638 struct vfssw *vsw;
639 struct vnode *mvp;
640 struct mounta mounta = { /* fake mounta for devfs_mount() */
641 NULL,
642 NULL,
643 MS_SYSSPACE,
644 NULL,
645 NULL,
646 0,
647 NULL,
648 0
649 };
650
651 /*
652 * _init devfs module to fill in the vfssw
653 */
654 if (modload("fs", "devfs") == -1)
655 panic("Cannot _init devfs module");
656
657 /*
658 * Hold vfs
659 */
660 RLOCK_VFSSW();
661 vsw = vfs_getvfsswbyname("devfs");
662 VFS_INIT(&devices, &vsw->vsw_vfsops, NULL);
663 VFS_HOLD(&devices);
664
665 /*
666 * Locate mount point
667 */
668 if (lookupname("/devices", UIO_SYSSPACE, FOLLOW, NULLVPP, &mvp))
669 panic("Cannot find /devices");
670
671 /*
672 * Perform the mount of /devices
673 */
674 if (VFS_MOUNT(&devices, mvp, &mounta, CRED()))
675 panic("Cannot mount /devices");
676
677 RUNLOCK_VFSSW();
678
679 /*
680 * Set appropriate members and add to vfs list for mnttab display
681 */
682 vfs_setresource(&devices, "/devices", 0);
683 vfs_setmntpoint(&devices, "/devices", 0);
684
685 /*
686 * Hold the root of /devices so it won't go away
687 */
688 if (VFS_ROOT(&devices, &devicesdir))
689 panic("vfs_mountdevices: not devices root");
690
691 if (vfs_lock(&devices) != 0) {
692 VN_RELE(devicesdir);
693 cmn_err(CE_NOTE, "Cannot acquire vfs_lock of /devices");
694 return;
695 }
696
697 if (vn_vfswlock(mvp) != 0) {
698 vfs_unlock(&devices);
699 VN_RELE(devicesdir);
700 cmn_err(CE_NOTE, "Cannot acquire vfswlock of /devices");
701 return;
702 }
703
704 vfs_add(mvp, &devices, 0);
705 vn_vfsunlock(mvp);
706 vfs_unlock(&devices);
707 VN_RELE(devicesdir);
708 }
709
710 /*
711 * mount the first instance of /dev to root and remain mounted
712 */
713 static void
714 vfs_mountdev1(void)
715 {
716 struct vfssw *vsw;
717 struct vnode *mvp;
718 struct mounta mounta = { /* fake mounta for sdev_mount() */
719 NULL,
720 NULL,
721 MS_SYSSPACE | MS_OVERLAY,
722 NULL,
723 NULL,
724 0,
725 NULL,
726 0
727 };
728
729 /*
730 * _init dev module to fill in the vfssw
731 */
732 if (modload("fs", "dev") == -1)
733 cmn_err(CE_PANIC, "Cannot _init dev module\n");
734
735 /*
736 * Hold vfs
737 */
738 RLOCK_VFSSW();
739 vsw = vfs_getvfsswbyname("dev");
740 VFS_INIT(&dev, &vsw->vsw_vfsops, NULL);
741 VFS_HOLD(&dev);
742
743 /*
744 * Locate mount point
745 */
746 if (lookupname("/dev", UIO_SYSSPACE, FOLLOW, NULLVPP, &mvp))
747 cmn_err(CE_PANIC, "Cannot find /dev\n");
748
749 /*
750 * Perform the mount of /dev
751 */
752 if (VFS_MOUNT(&dev, mvp, &mounta, CRED()))
753 cmn_err(CE_PANIC, "Cannot mount /dev 1\n");
754
755 RUNLOCK_VFSSW();
756
757 /*
758 * Set appropriate members and add to vfs list for mnttab display
759 */
760 vfs_setresource(&dev, "/dev", 0);
761 vfs_setmntpoint(&dev, "/dev", 0);
762
763 /*
764 * Hold the root of /dev so it won't go away
765 */
766 if (VFS_ROOT(&dev, &devdir))
767 cmn_err(CE_PANIC, "vfs_mountdev1: not dev root");
768
769 if (vfs_lock(&dev) != 0) {
770 VN_RELE(devdir);
771 cmn_err(CE_NOTE, "Cannot acquire vfs_lock of /dev");
772 return;
773 }
774
775 if (vn_vfswlock(mvp) != 0) {
776 vfs_unlock(&dev);
777 VN_RELE(devdir);
778 cmn_err(CE_NOTE, "Cannot acquire vfswlock of /dev");
779 return;
780 }
781
782 vfs_add(mvp, &dev, 0);
783 vn_vfsunlock(mvp);
784 vfs_unlock(&dev);
785 VN_RELE(devdir);
786 }
787
788 /*
789 * Mount required filesystem. This is done right after root is mounted.
790 */
791 static void
792 vfs_mountfs(char *module, char *spec, char *path)
793 {
794 struct vnode *mvp;
795 struct mounta mounta;
796 vfs_t *vfsp;
797
798 bzero(&mounta, sizeof (mounta));
799 mounta.flags = MS_SYSSPACE | MS_DATA;
800 mounta.fstype = module;
801 mounta.spec = spec;
802 mounta.dir = path;
803 if (lookupname(path, UIO_SYSSPACE, FOLLOW, NULLVPP, &mvp)) {
804 cmn_err(CE_WARN, "Cannot find %s", path);
805 return;
806 }
807 if (domount(NULL, &mounta, mvp, CRED(), &vfsp))
808 cmn_err(CE_WARN, "Cannot mount %s", path);
809 else
810 VFS_RELE(vfsp);
811 VN_RELE(mvp);
812 }
813
814 /*
815 * vfs_mountroot is called by main() to mount the root filesystem.
816 */
817 void
818 vfs_mountroot(void)
819 {
820 struct vnode *rvp = NULL;
821 char *path;
822 size_t plen;
823 struct vfssw *vswp;
824 proc_t *p;
825
826 rw_init(&vfssw_lock, NULL, RW_DEFAULT, NULL);
827 rw_init(&vfslist, NULL, RW_DEFAULT, NULL);
828
829 /*
830 * Alloc the vfs hash bucket array and locks
831 */
832 rvfs_list = kmem_zalloc(vfshsz * sizeof (rvfs_t), KM_SLEEP);
833
834 /*
835 * Call machine-dependent routine "rootconf" to choose a root
836 * file system type.
837 */
838 if (rootconf())
839 panic("vfs_mountroot: cannot mount root");
840 /*
841 * Get vnode for '/'. Set up rootdir, u.u_rdir and u.u_cdir
842 * to point to it. These are used by lookuppn() so that it
843 * knows where to start from ('/' or '.').
844 */
845 vfs_setmntpoint(rootvfs, "/", 0);
846 if (VFS_ROOT(rootvfs, &rootdir))
847 panic("vfs_mountroot: no root vnode");
848
849 /*
850 * At this point, the process tree consists of p0 and possibly some
851 * direct children of p0. (i.e. there are no grandchildren)
852 *
853 * Walk through them all, setting their current directory.
854 */
855 mutex_enter(&pidlock);
856 for (p = practive; p != NULL; p = p->p_next) {
857 ASSERT(p == &p0 || p->p_parent == &p0);
858
859 PTOU(p)->u_cdir = rootdir;
860 VN_HOLD(PTOU(p)->u_cdir);
861 PTOU(p)->u_rdir = NULL;
862 }
863 mutex_exit(&pidlock);
864
865 /*
866 * Setup the global zone's rootvp, now that it exists.
867 */
868 global_zone->zone_rootvp = rootdir;
869 VN_HOLD(global_zone->zone_rootvp);
870
871 /*
872 * Notify the module code that it can begin using the
873 * root filesystem instead of the boot program's services.
874 */
875 modrootloaded = 1;
876
877 /*
878 * Special handling for a ZFS root file system.
879 */
880 zfs_boot_init();
881
882 /*
883 * Set up mnttab information for root
884 */
885 vfs_setresource(rootvfs, rootfs.bo_name, 0);
886
887 /*
888 * Notify cluster software that the root filesystem is available.
889 */
890 clboot_mountroot();
891
892 /* Now that we're all done with the root FS, set up its vopstats */
893 if ((vswp = vfs_getvfsswbyvfsops(vfs_getops(rootvfs))) != NULL) {
894 /* Set flag for statistics collection */
895 if (vswp->vsw_flag & VSW_STATS) {
896 initialize_vopstats(&rootvfs->vfs_vopstats);
897 rootvfs->vfs_flag |= VFS_STATS;
898 rootvfs->vfs_fstypevsp =
899 get_fstype_vopstats(rootvfs, vswp);
900 rootvfs->vfs_vskap = get_vskstat_anchor(rootvfs);
901 }
902 vfs_unrefvfssw(vswp);
903 }
904
905 /*
906 * Mount /devices, /dev instance 1, /system/contract, /etc/mnttab,
907 * /etc/svc/volatile, /etc/dfs/sharetab, /system/object, and /proc.
908 */
909 vfs_mountdevices();
910 vfs_mountdev1();
911
912 vfs_mountfs("ctfs", "ctfs", CTFS_ROOT);
913 vfs_mountfs("proc", "/proc", "/proc");
914 vfs_mountfs("mntfs", "/etc/mnttab", "/etc/mnttab");
915 vfs_mountfs("tmpfs", "/etc/svc/volatile", "/etc/svc/volatile");
916 vfs_mountfs("objfs", "objfs", OBJFS_ROOT);
917 vfs_mountfs("bootfs", "bootfs", "/system/boot");
918
919 if (getzoneid() == GLOBAL_ZONEID) {
920 vfs_mountfs("sharefs", "sharefs", "/etc/dfs/sharetab");
921 }
922
923 if (strcmp(rootfs.bo_fstype, "zfs") != 0) {
924 /*
925 * Look up the root device via devfs so that a dv_node is
926 * created for it. The vnode is never VN_RELE()ed.
927 * We allocate more than MAXPATHLEN so that the
928 * buffer passed to i_ddi_prompath_to_devfspath() is
929 * exactly MAXPATHLEN (the function expects a buffer
930 * of that length).
931 */
932 plen = strlen("/devices");
933 path = kmem_alloc(plen + MAXPATHLEN, KM_SLEEP);
934 (void) strcpy(path, "/devices");
935
936 if (i_ddi_prompath_to_devfspath(rootfs.bo_name, path + plen)
937 != DDI_SUCCESS ||
938 lookupname(path, UIO_SYSSPACE, FOLLOW, NULLVPP, &rvp)) {
939
940 /* NUL terminate in case "path" has garbage */
941 path[plen + MAXPATHLEN - 1] = '\0';
942 #ifdef DEBUG
943 cmn_err(CE_WARN, "!Cannot lookup root device: %s",
944 path);
945 #endif
946 }
947 kmem_free(path, plen + MAXPATHLEN);
948 }
949
950 vfs_mnttabvp_setup();
951 }
952
953 /*
954 * Check to see if our "block device" is actually a file. If so,
955 * automatically add a lofi device, and keep track of this fact.
956 */
957 static int
958 lofi_add(const char *fsname, struct vfs *vfsp,
959 mntopts_t *mntopts, struct mounta *uap)
960 {
961 int fromspace = (uap->flags & MS_SYSSPACE) ?
962 UIO_SYSSPACE : UIO_USERSPACE;
963 struct lofi_ioctl *li = NULL;
964 struct vnode *vp = NULL;
965 struct pathname pn = { NULL };
966 ldi_ident_t ldi_id;
967 ldi_handle_t ldi_hdl;
968 vfssw_t *vfssw;
969 int id;
970 int err = 0;
971
972 if ((vfssw = vfs_getvfssw(fsname)) == NULL)
973 return (0);
974
975 if (!(vfssw->vsw_flag & VSW_CANLOFI)) {
976 vfs_unrefvfssw(vfssw);
977 return (0);
978 }
979
980 vfs_unrefvfssw(vfssw);
981 vfssw = NULL;
982
983 if (pn_get(uap->spec, fromspace, &pn) != 0)
984 return (0);
985
986 if (lookupname(uap->spec, fromspace, FOLLOW, NULL, &vp) != 0)
987 goto out;
988
989 if (vp->v_type != VREG)
990 goto out;
991
992 /* OK, this is a lofi mount. */
993
994 if ((uap->flags & (MS_REMOUNT|MS_GLOBAL)) ||
995 vfs_optionisset_nolock(mntopts, MNTOPT_SUID, NULL) ||
996 vfs_optionisset_nolock(mntopts, MNTOPT_SETUID, NULL) ||
997 vfs_optionisset_nolock(mntopts, MNTOPT_DEVICES, NULL)) {
998 err = EINVAL;
999 goto out;
1000 }
1001
1002 ldi_id = ldi_ident_from_anon();
1003 li = kmem_zalloc(sizeof (*li), KM_SLEEP);
1004 (void) strlcpy(li->li_filename, pn.pn_path, MAXPATHLEN);
1005
1006 err = ldi_open_by_name("/dev/lofictl", FREAD | FWRITE, kcred,
1007 &ldi_hdl, ldi_id);
1008
1009 if (err)
1010 goto out2;
1011
1012 err = ldi_ioctl(ldi_hdl, LOFI_MAP_FILE, (intptr_t)li,
1013 FREAD | FWRITE | FKIOCTL, kcred, &id);
1014
1015 (void) ldi_close(ldi_hdl, FREAD | FWRITE, kcred);
1016
1017 if (!err)
1018 vfsp->vfs_lofi_id = id;
1019
1020 out2:
1021 ldi_ident_release(ldi_id);
1022 out:
1023 if (li != NULL)
1024 kmem_free(li, sizeof (*li));
1025 if (vp != NULL)
1026 VN_RELE(vp);
1027 pn_free(&pn);
1028 return (err);
1029 }
1030
1031 static void
1032 lofi_remove(struct vfs *vfsp)
1033 {
1034 struct lofi_ioctl *li = NULL;
1035 ldi_ident_t ldi_id;
1036 ldi_handle_t ldi_hdl;
1037 int err;
1038
1039 if (vfsp->vfs_lofi_id == 0)
1040 return;
1041
1042 ldi_id = ldi_ident_from_anon();
1043
1044 li = kmem_zalloc(sizeof (*li), KM_SLEEP);
1045 li->li_id = vfsp->vfs_lofi_id;
1046 li->li_cleanup = B_TRUE;
1047
1048 err = ldi_open_by_name("/dev/lofictl", FREAD | FWRITE, kcred,
1049 &ldi_hdl, ldi_id);
1050
1051 if (err)
1052 goto out;
1053
1054 err = ldi_ioctl(ldi_hdl, LOFI_UNMAP_FILE_MINOR, (intptr_t)li,
1055 FREAD | FWRITE | FKIOCTL, kcred, NULL);
1056
1057 (void) ldi_close(ldi_hdl, FREAD | FWRITE, kcred);
1058
1059 if (!err)
1060 vfsp->vfs_lofi_id = 0;
1061
1062 out:
1063 ldi_ident_release(ldi_id);
1064 if (li != NULL)
1065 kmem_free(li, sizeof (*li));
1066 }
1067
1068 /*
1069 * Common mount code. Called from the system call entry point, from autofs,
1070 * nfsv4 trigger mounts, and from pxfs.
1071 *
1072 * Takes the effective file system type, mount arguments, the mount point
1073 * vnode, flags specifying whether the mount is a remount and whether it
1074 * should be entered into the vfs list, and credentials. Fills in its vfspp
1075 * parameter with the mounted file system instance's vfs.
1076 *
1077 * Note that the effective file system type is specified as a string. It may
1078 * be null, in which case it's determined from the mount arguments, and may
1079 * differ from the type specified in the mount arguments; this is a hook to
1080 * allow interposition when instantiating file system instances.
1081 *
1082 * The caller is responsible for releasing its own hold on the mount point
1083 * vp (this routine does its own hold when necessary).
1084 * Also note that for remounts, the mount point vp should be the vnode for
1085 * the root of the file system rather than the vnode that the file system
1086 * is mounted on top of.
1087 */
1088 int
1089 domount(char *fsname, struct mounta *uap, vnode_t *vp, struct cred *credp,
1090 struct vfs **vfspp)
1091 {
1092 struct vfssw *vswp;
1093 vfsops_t *vfsops;
1094 struct vfs *vfsp;
1095 struct vnode *bvp;
1096 dev_t bdev = 0;
1097 mntopts_t mnt_mntopts;
1098 int error = 0;
1099 int copyout_error = 0;
1100 int ovflags;
1101 char *opts = uap->optptr;
1102 char *inargs = opts;
1103 int optlen = uap->optlen;
1104 int remount;
1105 int rdonly;
1106 int nbmand = 0;
1107 int delmip = 0;
1108 int addmip = 0;
1109 int splice = ((uap->flags & MS_NOSPLICE) == 0);
1110 int fromspace = (uap->flags & MS_SYSSPACE) ?
1111 UIO_SYSSPACE : UIO_USERSPACE;
1112 char *resource = NULL, *mountpt = NULL;
1113 refstr_t *oldresource, *oldmntpt;
1114 struct pathname pn, rpn;
1115 vsk_anchor_t *vskap;
1116 char fstname[FSTYPSZ];
1117 zone_t *zone;
1118
1119 /*
1120 * The v_flag value for the mount point vp is permanently set
1121 * to VVFSLOCK so that no one bypasses the vn_vfs*locks routine
1122 * for mount point locking.
1123 */
1124 mutex_enter(&vp->v_lock);
1125 vp->v_flag |= VVFSLOCK;
1126 mutex_exit(&vp->v_lock);
1127
1128 mnt_mntopts.mo_count = 0;
1129 /*
1130 * Find the ops vector to use to invoke the file system-specific mount
1131 * method. If the fsname argument is non-NULL, use it directly.
1132 * Otherwise, dig the file system type information out of the mount
1133 * arguments.
1134 *
1135 * A side effect is to hold the vfssw entry.
1136 *
1137 * Mount arguments can be specified in several ways, which are
1138 * distinguished by flag bit settings. The preferred way is to set
1139 * MS_OPTIONSTR, indicating an 8 argument mount with the file system
1140 * type supplied as a character string and the last two arguments
1141 * being a pointer to a character buffer and the size of the buffer.
1142 * On entry, the buffer holds a null terminated list of options; on
1143 * return, the string is the list of options the file system
1144 * recognized. If MS_DATA is set arguments five and six point to a
1145 * block of binary data which the file system interprets.
1146 * A further wrinkle is that some callers don't set MS_FSS and MS_DATA
1147 * consistently with these conventions. To handle them, we check to
1148 * see whether the pointer to the file system name has a numeric value
1149 * less than 256. If so, we treat it as an index.
1150 */
1151 if (fsname != NULL) {
1152 if ((vswp = vfs_getvfssw(fsname)) == NULL) {
1153 return (EINVAL);
1154 }
1155 } else if (uap->flags & (MS_OPTIONSTR | MS_DATA | MS_FSS)) {
1156 size_t n;
1157 uint_t fstype;
1158
1159 fsname = fstname;
1160
1161 if ((fstype = (uintptr_t)uap->fstype) < 256) {
1162 RLOCK_VFSSW();
1163 if (fstype == 0 || fstype >= nfstype ||
1164 !ALLOCATED_VFSSW(&vfssw[fstype])) {
1165 RUNLOCK_VFSSW();
1166 return (EINVAL);
1167 }
1168 (void) strcpy(fsname, vfssw[fstype].vsw_name);
1169 RUNLOCK_VFSSW();
1170 if ((vswp = vfs_getvfssw(fsname)) == NULL)
1171 return (EINVAL);
1172 } else {
1173 /*
1174 * Handle either kernel or user address space.
1175 */
1176 if (uap->flags & MS_SYSSPACE) {
1177 error = copystr(uap->fstype, fsname,
1178 FSTYPSZ, &n);
1179 } else {
1180 error = copyinstr(uap->fstype, fsname,
1181 FSTYPSZ, &n);
1182 }
1183 if (error) {
1184 if (error == ENAMETOOLONG)
1185 return (EINVAL);
1186 return (error);
1187 }
1188 if ((vswp = vfs_getvfssw(fsname)) == NULL)
1189 return (EINVAL);
1190 }
1191 } else {
1192 if ((vswp = vfs_getvfsswbyvfsops(vfs_getops(rootvfs))) == NULL)
1193 return (EINVAL);
1194 fsname = vswp->vsw_name;
1195 }
1196 if (!VFS_INSTALLED(vswp))
1197 return (EINVAL);
1198
1199 if ((error = secpolicy_fs_allowed_mount(fsname)) != 0) {
1200 vfs_unrefvfssw(vswp);
1201 return (error);
1202 }
1203
1204 vfsops = &vswp->vsw_vfsops;
1205
1206 vfs_copyopttbl(&vswp->vsw_optproto, &mnt_mntopts);
1207 /*
1208 * Fetch mount options and parse them for generic vfs options
1209 */
1210 if (uap->flags & MS_OPTIONSTR) {
1211 /*
1212 * Limit the buffer size
1213 */
1214 if (optlen < 0 || optlen > MAX_MNTOPT_STR) {
1215 error = EINVAL;
1216 goto errout;
1217 }
1218 if ((uap->flags & MS_SYSSPACE) == 0) {
1219 inargs = kmem_alloc(MAX_MNTOPT_STR, KM_SLEEP);
1220 inargs[0] = '\0';
1221 if (optlen) {
1222 error = copyinstr(opts, inargs, (size_t)optlen,
1223 NULL);
1224 if (error) {
1225 goto errout;
1226 }
1227 }
1228 }
1229 vfs_parsemntopts(&mnt_mntopts, inargs, 0);
1230 }
1231 /*
1232 * Flag bits override the options string.
1233 */
1234 if (uap->flags & MS_REMOUNT)
1235 vfs_setmntopt_nolock(&mnt_mntopts, MNTOPT_REMOUNT, NULL, 0, 0);
1236 if (uap->flags & MS_RDONLY)
1237 vfs_setmntopt_nolock(&mnt_mntopts, MNTOPT_RO, NULL, 0, 0);
1238 if (uap->flags & MS_NOSUID)
1239 vfs_setmntopt_nolock(&mnt_mntopts, MNTOPT_NOSUID, NULL, 0, 0);
1240
1241 /*
1242 * Check if this is a remount; must be set in the option string and
1243 * the file system must support a remount option.
1244 */
1245 if (remount = vfs_optionisset_nolock(&mnt_mntopts,
1246 MNTOPT_REMOUNT, NULL)) {
1247 if (!(vswp->vsw_flag & VSW_CANREMOUNT)) {
1248 error = ENOTSUP;
1249 goto errout;
1250 }
1251 uap->flags |= MS_REMOUNT;
1252 }
1253
1254 /*
1255 * uap->flags and vfs_optionisset() should agree.
1256 */
1257 if (rdonly = vfs_optionisset_nolock(&mnt_mntopts, MNTOPT_RO, NULL)) {
1258 uap->flags |= MS_RDONLY;
1259 }
1260 if (vfs_optionisset_nolock(&mnt_mntopts, MNTOPT_NOSUID, NULL)) {
1261 uap->flags |= MS_NOSUID;
1262 }
1263 nbmand = vfs_optionisset_nolock(&mnt_mntopts, MNTOPT_NBMAND, NULL);
1264 ASSERT(splice || !remount);
1265 /*
1266 * If we are splicing the fs into the namespace,
1267 * perform mount point checks.
1268 *
1269 * We want to resolve the path for the mount point to eliminate
1270 * '.' and ".." and symlinks in mount points; we can't do the
1271 * same for the resource string, since it would turn
1272 * "/dev/dsk/c0t0d0s0" into "/devices/pci@...". We need to do
1273 * this before grabbing vn_vfswlock(), because otherwise we
1274 * would deadlock with lookuppn().
1275 */
1276 if (splice) {
1277 ASSERT(vp->v_count > 0);
1278
1279 /*
1280 * Pick up mount point and device from appropriate space.
1281 */
1282 if (pn_get(uap->spec, fromspace, &pn) == 0) {
1283 resource = kmem_alloc(pn.pn_pathlen + 1,
1284 KM_SLEEP);
1285 (void) strcpy(resource, pn.pn_path);
1286 pn_free(&pn);
1287 }
1288 /*
1289 * Do a lookupname prior to taking the
1290 * writelock. Mark this as completed if
1291 * successful for later cleanup and addition to
1292 * the mount in progress table.
1293 */
1294 if ((vswp->vsw_flag & VSW_MOUNTDEV) &&
1295 (uap->flags & MS_GLOBAL) == 0 &&
1296 lookupname(uap->spec, fromspace,
1297 FOLLOW, NULL, &bvp) == 0) {
1298 addmip = 1;
1299 }
1300
1301 if ((error = pn_get(uap->dir, fromspace, &pn)) == 0) {
1302 pathname_t *pnp;
1303
1304 if (*pn.pn_path != '/') {
1305 error = EINVAL;
1306 pn_free(&pn);
1307 goto errout;
1308 }
1309 pn_alloc(&rpn);
1310 /*
1311 * Kludge to prevent autofs from deadlocking with
1312 * itself when it calls domount().
1313 *
1314 * If autofs is calling, it is because it is doing
1315 * (autofs) mounts in the process of an NFS mount. A
1316 * lookuppn() here would cause us to block waiting for
1317 * said NFS mount to complete, which can't since this
1318 * is the thread that was supposed to doing it.
1319 */
1320 if (fromspace == UIO_USERSPACE) {
1321 if ((error = lookuppn(&pn, &rpn, FOLLOW, NULL,
1322 NULL)) == 0) {
1323 pnp = &rpn;
1324 } else {
1325 /*
1326 * The file disappeared or otherwise
1327 * became inaccessible since we opened
1328 * it; might as well fail the mount
1329 * since the mount point is no longer
1330 * accessible.
1331 */
1332 pn_free(&rpn);
1333 pn_free(&pn);
1334 goto errout;
1335 }
1336 } else {
1337 pnp = &pn;
1338 }
1339 mountpt = kmem_alloc(pnp->pn_pathlen + 1, KM_SLEEP);
1340 (void) strcpy(mountpt, pnp->pn_path);
1341
1342 /*
1343 * If the addition of the zone's rootpath
1344 * would push us over a total path length
1345 * of MAXPATHLEN, we fail the mount with
1346 * ENAMETOOLONG, which is what we would have
1347 * gotten if we were trying to perform the same
1348 * mount in the global zone.
1349 *
1350 * strlen() doesn't count the trailing
1351 * '\0', but zone_rootpathlen counts both a
1352 * trailing '/' and the terminating '\0'.
1353 */
1354 if ((curproc->p_zone->zone_rootpathlen - 1 +
1355 strlen(mountpt)) > MAXPATHLEN ||
1356 (resource != NULL &&
1357 (curproc->p_zone->zone_rootpathlen - 1 +
1358 strlen(resource)) > MAXPATHLEN)) {
1359 error = ENAMETOOLONG;
1360 }
1361
1362 pn_free(&rpn);
1363 pn_free(&pn);
1364 }
1365
1366 if (error)
1367 goto errout;
1368
1369 /*
1370 * Prevent path name resolution from proceeding past
1371 * the mount point.
1372 */
1373 if (vn_vfswlock(vp) != 0) {
1374 error = EBUSY;
1375 goto errout;
1376 }
1377
1378 /*
1379 * Verify that it's legitimate to establish a mount on
1380 * the prospective mount point.
1381 */
1382 if (vn_mountedvfs(vp) != NULL) {
1383 /*
1384 * The mount point lock was obtained after some
1385 * other thread raced through and established a mount.
1386 */
1387 vn_vfsunlock(vp);
1388 error = EBUSY;
1389 goto errout;
1390 }
1391 if (vp->v_flag & VNOMOUNT) {
1392 vn_vfsunlock(vp);
1393 error = EINVAL;
1394 goto errout;
1395 }
1396 }
1397 if ((uap->flags & (MS_DATA | MS_OPTIONSTR)) == 0) {
1398 uap->dataptr = NULL;
1399 uap->datalen = 0;
1400 }
1401
1402 /*
1403 * If this is a remount, we don't want to create a new VFS.
1404 * Instead, we pass the existing one with a remount flag.
1405 */
1406 if (remount) {
1407 /*
1408 * Confirm that the mount point is the root vnode of the
1409 * file system that is being remounted.
1410 * This can happen if the user specifies a different
1411 * mount point directory pathname in the (re)mount command.
1412 *
1413 * Code below can only be reached if splice is true, so it's
1414 * safe to do vn_vfsunlock() here.
1415 */
1416 if ((vp->v_flag & VROOT) == 0) {
1417 vn_vfsunlock(vp);
1418 error = ENOENT;
1419 goto errout;
1420 }
1421 /*
1422 * Disallow making file systems read-only unless file system
1423 * explicitly allows it in its vfssw. Ignore other flags.
1424 */
1425 if (rdonly && vn_is_readonly(vp) == 0 &&
1426 (vswp->vsw_flag & VSW_CANRWRO) == 0) {
1427 vn_vfsunlock(vp);
1428 error = EINVAL;
1429 goto errout;
1430 }
1431 /*
1432 * Disallow changing the NBMAND disposition of the file
1433 * system on remounts.
1434 */
1435 if ((nbmand && ((vp->v_vfsp->vfs_flag & VFS_NBMAND) == 0)) ||
1436 (!nbmand && (vp->v_vfsp->vfs_flag & VFS_NBMAND))) {
1437 vn_vfsunlock(vp);
1438 error = EINVAL;
1439 goto errout;
1440 }
1441 vfsp = vp->v_vfsp;
1442 ovflags = vfsp->vfs_flag;
1443 vfsp->vfs_flag |= VFS_REMOUNT;
1444 vfsp->vfs_flag &= ~VFS_RDONLY;
1445 } else {
1446 vfsp = vfs_alloc(KM_SLEEP);
1447 VFS_INIT(vfsp, vfsops, NULL);
1448 }
1449
1450 VFS_HOLD(vfsp);
1451
1452 if ((error = lofi_add(fsname, vfsp, &mnt_mntopts, uap)) != 0) {
1453 if (!remount) {
1454 if (splice)
1455 vn_vfsunlock(vp);
1456 vfs_free(vfsp);
1457 } else {
1458 vn_vfsunlock(vp);
1459 VFS_RELE(vfsp);
1460 }
1461 goto errout;
1462 }
1463
1464 /*
1465 * PRIV_SYS_MOUNT doesn't mean you can become root.
1466 */
1467 if (vfsp->vfs_lofi_id != 0) {
1468 uap->flags |= MS_NOSUID;
1469 vfs_setmntopt_nolock(&mnt_mntopts, MNTOPT_NOSUID, NULL, 0, 0);
1470 }
1471
1472 /*
1473 * The vfs_reflock is not used anymore the code below explicitly
1474 * holds it preventing others accesing it directly.
1475 */
1476 if ((sema_tryp(&vfsp->vfs_reflock) == 0) &&
1477 !(vfsp->vfs_flag & VFS_REMOUNT))
1478 cmn_err(CE_WARN,
1479 "mount type %s couldn't get vfs_reflock", vswp->vsw_name);
1480
1481 /*
1482 * Lock the vfs. If this is a remount we want to avoid spurious umount
1483 * failures that happen as a side-effect of fsflush() and other mount
1484 * and unmount operations that might be going on simultaneously and
1485 * may have locked the vfs currently. To not return EBUSY immediately
1486 * here we use vfs_lock_wait() instead vfs_lock() for the remount case.
1487 */
1488 if (!remount) {
1489 if (error = vfs_lock(vfsp)) {
1490 vfsp->vfs_flag = ovflags;
1491
1492 lofi_remove(vfsp);
1493
1494 if (splice)
1495 vn_vfsunlock(vp);
1496 vfs_free(vfsp);
1497 goto errout;
1498 }
1499 } else {
1500 vfs_lock_wait(vfsp);
1501 }
1502
1503 /*
1504 * Add device to mount in progress table, global mounts require special
1505 * handling. It is possible that we have already done the lookupname
1506 * on a spliced, non-global fs. If so, we don't want to do it again
1507 * since we cannot do a lookupname after taking the
1508 * wlock above. This case is for a non-spliced, non-global filesystem.
1509 */
1510 if (!addmip) {
1511 if ((vswp->vsw_flag & VSW_MOUNTDEV) &&
1512 (uap->flags & MS_GLOBAL) == 0 &&
1513 lookupname(uap->spec, fromspace, FOLLOW, NULL, &bvp) == 0) {
1514 addmip = 1;
1515 }
1516 }
1517
1518 if (addmip) {
1519 vnode_t *lvp = NULL;
1520
1521 error = vfs_get_lofi(vfsp, &lvp);
1522 if (error > 0) {
1523 lofi_remove(vfsp);
1524
1525 if (splice)
1526 vn_vfsunlock(vp);
1527 vfs_unlock(vfsp);
1528
1529 if (remount) {
1530 VFS_RELE(vfsp);
1531 } else {
1532 vfs_free(vfsp);
1533 }
1534
1535 goto errout;
1536 } else if (error == -1) {
1537 bdev = bvp->v_rdev;
1538 VN_RELE(bvp);
1539 } else {
1540 bdev = lvp->v_rdev;
1541 VN_RELE(lvp);
1542 VN_RELE(bvp);
1543 }
1544
1545 vfs_addmip(bdev, vfsp);
1546 addmip = 0;
1547 delmip = 1;
1548 }
1549 /*
1550 * Invalidate cached entry for the mount point.
1551 */
1552 if (splice)
1553 dnlc_purge_vp(vp);
1554
1555 /*
1556 * If have an option string but the filesystem doesn't supply a
1557 * prototype options table, create a table with the global
1558 * options and sufficient room to accept all the options in the
1559 * string. Then parse the passed in option string
1560 * accepting all the options in the string. This gives us an
1561 * option table with all the proper cancel properties for the
1562 * global options.
1563 *
1564 * Filesystems that supply a prototype options table are handled
1565 * earlier in this function.
1566 */
1567 if (uap->flags & MS_OPTIONSTR) {
1568 if (!(vswp->vsw_flag & VSW_HASPROTO)) {
1569 mntopts_t tmp_mntopts;
1570
1571 tmp_mntopts.mo_count = 0;
1572 vfs_createopttbl_extend(&tmp_mntopts, inargs,
1573 &mnt_mntopts);
1574 vfs_parsemntopts(&tmp_mntopts, inargs, 1);
1575 vfs_swapopttbl_nolock(&mnt_mntopts, &tmp_mntopts);
1576 vfs_freeopttbl(&tmp_mntopts);
1577 }
1578 }
1579
1580 /*
1581 * Serialize with zone state transitions.
1582 * See vfs_list_add; zone mounted into is:
1583 * zone_find_by_path(refstr_value(vfsp->vfs_mntpt))
1584 * not the zone doing the mount (curproc->p_zone), but if we're already
1585 * inside a NGZ, then we know what zone we are.
1586 */
1587 if (INGLOBALZONE(curproc)) {
1588 zone = zone_find_by_path(mountpt);
1589 ASSERT(zone != NULL);
1590 } else {
1591 zone = curproc->p_zone;
1592 /*
1593 * zone_find_by_path does a hold, so do one here too so that
1594 * we can do a zone_rele after mount_completed.
1595 */
1596 zone_hold(zone);
1597 }
1598 mount_in_progress(zone);
1599 /*
1600 * Instantiate (or reinstantiate) the file system. If appropriate,
1601 * splice it into the file system name space.
1602 *
1603 * We want VFS_MOUNT() to be able to override the vfs_resource
1604 * string if necessary (ie, mntfs), and also for a remount to
1605 * change the same (necessary when remounting '/' during boot).
1606 * So we set up vfs_mntpt and vfs_resource to what we think they
1607 * should be, then hand off control to VFS_MOUNT() which can
1608 * override this.
1609 *
1610 * For safety's sake, when changing vfs_resource or vfs_mntpt of
1611 * a vfs which is on the vfs list (i.e. during a remount), we must
1612 * never set those fields to NULL. Several bits of code make
1613 * assumptions that the fields are always valid.
1614 */
1615 vfs_swapopttbl(&mnt_mntopts, &vfsp->vfs_mntopts);
1616 if (remount) {
1617 if ((oldresource = vfsp->vfs_resource) != NULL)
1618 refstr_hold(oldresource);
1619 if ((oldmntpt = vfsp->vfs_mntpt) != NULL)
1620 refstr_hold(oldmntpt);
1621 }
1622 vfs_setresource(vfsp, resource, 0);
1623 vfs_setmntpoint(vfsp, mountpt, 0);
1624
1625 /*
1626 * going to mount on this vnode, so notify.
1627 */
1628 vnevent_mountedover(vp, NULL);
1629 error = VFS_MOUNT(vfsp, vp, uap, credp);
1630
1631 if (uap->flags & MS_RDONLY)
1632 vfs_setmntopt(vfsp, MNTOPT_RO, NULL, 0);
1633 if (uap->flags & MS_NOSUID)
1634 vfs_setmntopt(vfsp, MNTOPT_NOSUID, NULL, 0);
1635 if (uap->flags & MS_GLOBAL)
1636 vfs_setmntopt(vfsp, MNTOPT_GLOBAL, NULL, 0);
1637
1638 if (error) {
1639 lofi_remove(vfsp);
1640
1641 if (remount) {
1642 /* put back pre-remount options */
1643 vfs_swapopttbl(&mnt_mntopts, &vfsp->vfs_mntopts);
1644 vfs_setmntpoint(vfsp, refstr_value(oldmntpt),
1645 VFSSP_VERBATIM);
1646 if (oldmntpt)
1647 refstr_rele(oldmntpt);
1648 vfs_setresource(vfsp, refstr_value(oldresource),
1649 VFSSP_VERBATIM);
1650 if (oldresource)
1651 refstr_rele(oldresource);
1652 vfsp->vfs_flag = ovflags;
1653 vfs_unlock(vfsp);
1654 VFS_RELE(vfsp);
1655 } else {
1656 vfs_unlock(vfsp);
1657 vfs_freemnttab(vfsp);
1658 vfs_free(vfsp);
1659 }
1660 } else {
1661 /*
1662 * Set the mount time to now
1663 */
1664 vfsp->vfs_mtime = ddi_get_time();
1665 if (remount) {
1666 vfsp->vfs_flag &= ~VFS_REMOUNT;
1667 if (oldresource)
1668 refstr_rele(oldresource);
1669 if (oldmntpt)
1670 refstr_rele(oldmntpt);
1671 } else if (splice) {
1672 /*
1673 * Link vfsp into the name space at the mount
1674 * point. Vfs_add() is responsible for
1675 * holding the mount point which will be
1676 * released when vfs_remove() is called.
1677 */
1678 vfs_add(vp, vfsp, uap->flags);
1679 } else {
1680 /*
1681 * Hold the reference to file system which is
1682 * not linked into the name space.
1683 */
1684 vfsp->vfs_zone = NULL;
1685 VFS_HOLD(vfsp);
1686 vfsp->vfs_vnodecovered = NULL;
1687 }
1688 /*
1689 * Set flags for global options encountered
1690 */
1691 if (vfs_optionisset(vfsp, MNTOPT_RO, NULL))
1692 vfsp->vfs_flag |= VFS_RDONLY;
1693 else
1694 vfsp->vfs_flag &= ~VFS_RDONLY;
1695 if (vfs_optionisset(vfsp, MNTOPT_NOSUID, NULL)) {
1696 vfsp->vfs_flag |= (VFS_NOSETUID|VFS_NODEVICES);
1697 } else {
1698 if (vfs_optionisset(vfsp, MNTOPT_NODEVICES, NULL))
1699 vfsp->vfs_flag |= VFS_NODEVICES;
1700 else
1701 vfsp->vfs_flag &= ~VFS_NODEVICES;
1702 if (vfs_optionisset(vfsp, MNTOPT_NOSETUID, NULL))
1703 vfsp->vfs_flag |= VFS_NOSETUID;
1704 else
1705 vfsp->vfs_flag &= ~VFS_NOSETUID;
1706 }
1707 if (vfs_optionisset(vfsp, MNTOPT_NBMAND, NULL))
1708 vfsp->vfs_flag |= VFS_NBMAND;
1709 else
1710 vfsp->vfs_flag &= ~VFS_NBMAND;
1711
1712 if (vfs_optionisset(vfsp, MNTOPT_XATTR, NULL))
1713 vfsp->vfs_flag |= VFS_XATTR;
1714 else
1715 vfsp->vfs_flag &= ~VFS_XATTR;
1716
1717 if (vfs_optionisset(vfsp, MNTOPT_NOEXEC, NULL))
1718 vfsp->vfs_flag |= VFS_NOEXEC;
1719 else
1720 vfsp->vfs_flag &= ~VFS_NOEXEC;
1721
1722 /*
1723 * Now construct the output option string of options
1724 * we recognized.
1725 */
1726 if (uap->flags & MS_OPTIONSTR) {
1727 vfs_list_read_lock();
1728 copyout_error = vfs_buildoptionstr(
1729 &vfsp->vfs_mntopts, inargs, optlen);
1730 vfs_list_unlock();
1731 if (copyout_error == 0 &&
1732 (uap->flags & MS_SYSSPACE) == 0) {
1733 copyout_error = copyoutstr(inargs, opts,
1734 optlen, NULL);
1735 }
1736 }
1737
1738 /*
1739 * If this isn't a remount, set up the vopstats before
1740 * anyone can touch this. We only allow spliced file
1741 * systems (file systems which are in the namespace) to
1742 * have the VFS_STATS flag set.
1743 * NOTE: PxFS mounts the underlying file system with
1744 * MS_NOSPLICE set and copies those vfs_flags to its private
1745 * vfs structure. As a result, PxFS should never have
1746 * the VFS_STATS flag or else we might access the vfs
1747 * statistics-related fields prior to them being
1748 * properly initialized.
1749 */
1750 if (!remount && (vswp->vsw_flag & VSW_STATS) && splice) {
1751 initialize_vopstats(&vfsp->vfs_vopstats);
1752 /*
1753 * We need to set vfs_vskap to NULL because there's
1754 * a chance it won't be set below. This is checked
1755 * in teardown_vopstats() so we can't have garbage.
1756 */
1757 vfsp->vfs_vskap = NULL;
1758 vfsp->vfs_flag |= VFS_STATS;
1759 vfsp->vfs_fstypevsp = get_fstype_vopstats(vfsp, vswp);
1760 }
1761
1762 if (vswp->vsw_flag & VSW_XID)
1763 vfsp->vfs_flag |= VFS_XID;
1764
1765 vfs_unlock(vfsp);
1766 }
1767 mount_completed(zone);
1768 zone_rele(zone);
1769 if (splice)
1770 vn_vfsunlock(vp);
1771
1772 if ((error == 0) && (copyout_error == 0)) {
1773 if (!remount) {
1774 /*
1775 * Don't call get_vskstat_anchor() while holding
1776 * locks since it allocates memory and calls
1777 * VFS_STATVFS(). For NFS, the latter can generate
1778 * an over-the-wire call.
1779 */
1780 vskap = get_vskstat_anchor(vfsp);
1781 /* Only take the lock if we have something to do */
1782 if (vskap != NULL) {
1783 vfs_lock_wait(vfsp);
1784 if (vfsp->vfs_flag & VFS_STATS) {
1785 vfsp->vfs_vskap = vskap;
1786 }
1787 vfs_unlock(vfsp);
1788 }
1789 }
1790 /* Return vfsp to caller. */
1791 *vfspp = vfsp;
1792 }
1793 errout:
1794 vfs_freeopttbl(&mnt_mntopts);
1795 if (resource != NULL)
1796 kmem_free(resource, strlen(resource) + 1);
1797 if (mountpt != NULL)
1798 kmem_free(mountpt, strlen(mountpt) + 1);
1799 /*
1800 * It is possible we errored prior to adding to mount in progress
1801 * table. Must free vnode we acquired with successful lookupname.
1802 */
1803 if (addmip)
1804 VN_RELE(bvp);
1805 if (delmip)
1806 vfs_delmip(vfsp);
1807 ASSERT(vswp != NULL);
1808 vfs_unrefvfssw(vswp);
1809 if (inargs != opts)
1810 kmem_free(inargs, MAX_MNTOPT_STR);
1811 if (copyout_error) {
1812 lofi_remove(vfsp);
1813 VFS_RELE(vfsp);
1814 error = copyout_error;
1815 }
1816 return (error);
1817 }
1818
1819 static void
1820 vfs_setpath(
1821 struct vfs *vfsp, /* vfs being updated */
1822 refstr_t **refp, /* Ref-count string to contain the new path */
1823 const char *newpath, /* Path to add to refp (above) */
1824 uint32_t flag) /* flag */
1825 {
1826 size_t len;
1827 refstr_t *ref;
1828 zone_t *zone = curproc->p_zone;
1829 char *sp;
1830 int have_list_lock = 0;
1831
1832 ASSERT(!VFS_ON_LIST(vfsp) || vfs_lock_held(vfsp));
1833
1834 /*
1835 * New path must be less than MAXPATHLEN because mntfs
1836 * will only display up to MAXPATHLEN bytes. This is currently
1837 * safe, because domount() uses pn_get(), and other callers
1838 * similarly cap the size to fewer than MAXPATHLEN bytes.
1839 */
1840
1841 ASSERT(strlen(newpath) < MAXPATHLEN);
1842
1843 /* mntfs requires consistency while vfs list lock is held */
1844
1845 if (VFS_ON_LIST(vfsp)) {
1846 have_list_lock = 1;
1847 vfs_list_lock();
1848 }
1849
1850 if (*refp != NULL)
1851 refstr_rele(*refp);
1852
1853 /*
1854 * If we are in a non-global zone then we prefix the supplied path,
1855 * newpath, with the zone's root path, with two exceptions. The first
1856 * is where we have been explicitly directed to avoid doing so; this
1857 * will be the case following a failed remount, where the path supplied
1858 * will be a saved version which must now be restored. The second
1859 * exception is where newpath is not a pathname but a descriptive name,
1860 * e.g. "procfs".
1861 */
1862 if (zone == global_zone || (flag & VFSSP_VERBATIM) || *newpath != '/') {
1863 ref = refstr_alloc(newpath);
1864 goto out;
1865 }
1866
1867 /*
1868 * Truncate the trailing '/' in the zoneroot, and merge
1869 * in the zone's rootpath with the "newpath" (resource
1870 * or mountpoint) passed in.
1871 *
1872 * The size of the required buffer is thus the size of
1873 * the buffer required for the passed-in newpath
1874 * (strlen(newpath) + 1), plus the size of the buffer
1875 * required to hold zone_rootpath (zone_rootpathlen)
1876 * minus one for one of the now-superfluous NUL
1877 * terminations, minus one for the trailing '/'.
1878 *
1879 * That gives us:
1880 *
1881 * (strlen(newpath) + 1) + zone_rootpathlen - 1 - 1
1882 *
1883 * Which is what we have below.
1884 */
1885
1886 len = strlen(newpath) + zone->zone_rootpathlen - 1;
1887 sp = kmem_alloc(len, KM_SLEEP);
1888
1889 /*
1890 * Copy everything including the trailing slash, which
1891 * we then overwrite with the NUL character.
1892 */
1893
1894 (void) strcpy(sp, zone->zone_rootpath);
1895 sp[zone->zone_rootpathlen - 2] = '\0';
1896 (void) strcat(sp, newpath);
1897
1898 ref = refstr_alloc(sp);
1899 kmem_free(sp, len);
1900 out:
1901 *refp = ref;
1902
1903 if (have_list_lock) {
1904 vfs_mnttab_modtimeupd();
1905 vfs_list_unlock();
1906 }
1907 }
1908
1909 /*
1910 * Record a mounted resource name in a vfs structure.
1911 * If vfsp is already mounted, caller must hold the vfs lock.
1912 */
1913 void
1914 vfs_setresource(struct vfs *vfsp, const char *resource, uint32_t flag)
1915 {
1916 if (resource == NULL || resource[0] == '\0')
1917 resource = VFS_NORESOURCE;
1918 vfs_setpath(vfsp, &vfsp->vfs_resource, resource, flag);
1919 }
1920
1921 /*
1922 * Record a mount point name in a vfs structure.
1923 * If vfsp is already mounted, caller must hold the vfs lock.
1924 */
1925 void
1926 vfs_setmntpoint(struct vfs *vfsp, const char *mntpt, uint32_t flag)
1927 {
1928 if (mntpt == NULL || mntpt[0] == '\0')
1929 mntpt = VFS_NOMNTPT;
1930 vfs_setpath(vfsp, &vfsp->vfs_mntpt, mntpt, flag);
1931 }
1932
1933 /* Returns the vfs_resource. Caller must call refstr_rele() when finished. */
1934
1935 refstr_t *
1936 vfs_getresource(const struct vfs *vfsp)
1937 {
1938 refstr_t *resource;
1939
1940 vfs_list_read_lock();
1941 resource = vfsp->vfs_resource;
1942 refstr_hold(resource);
1943 vfs_list_unlock();
1944
1945 return (resource);
1946 }
1947
1948 /* Returns the vfs_mntpt. Caller must call refstr_rele() when finished. */
1949
1950 refstr_t *
1951 vfs_getmntpoint(const struct vfs *vfsp)
1952 {
1953 refstr_t *mntpt;
1954
1955 vfs_list_read_lock();
1956 mntpt = vfsp->vfs_mntpt;
1957 refstr_hold(mntpt);
1958 vfs_list_unlock();
1959
1960 return (mntpt);
1961 }
1962
1963 /*
1964 * Create an empty options table with enough empty slots to hold all
1965 * The options in the options string passed as an argument.
1966 * Potentially prepend another options table.
1967 *
1968 * Note: caller is responsible for locking the vfs list, if needed,
1969 * to protect mops.
1970 */
1971 static void
1972 vfs_createopttbl_extend(mntopts_t *mops, const char *opts,
1973 const mntopts_t *mtmpl)
1974 {
1975 const char *s = opts;
1976 uint_t count;
1977
1978 if (opts == NULL || *opts == '\0') {
1979 count = 0;
1980 } else {
1981 count = 1;
1982
1983 /*
1984 * Count number of options in the string
1985 */
1986 for (s = strchr(s, ','); s != NULL; s = strchr(s, ',')) {
1987 count++;
1988 s++;
1989 }
1990 }
1991 vfs_copyopttbl_extend(mtmpl, mops, count);
1992 }
1993
1994 /*
1995 * Create an empty options table with enough empty slots to hold all
1996 * The options in the options string passed as an argument.
1997 *
1998 * This function is *not* for general use by filesystems.
1999 *
2000 * Note: caller is responsible for locking the vfs list, if needed,
2001 * to protect mops.
2002 */
2003 void
2004 vfs_createopttbl(mntopts_t *mops, const char *opts)
2005 {
2006 vfs_createopttbl_extend(mops, opts, NULL);
2007 }
2008
2009
2010 /*
2011 * Swap two mount options tables
2012 */
2013 static void
2014 vfs_swapopttbl_nolock(mntopts_t *optbl1, mntopts_t *optbl2)
2015 {
2016 uint_t tmpcnt;
2017 mntopt_t *tmplist;
2018
2019 tmpcnt = optbl2->mo_count;
2020 tmplist = optbl2->mo_list;
2021 optbl2->mo_count = optbl1->mo_count;
2022 optbl2->mo_list = optbl1->mo_list;
2023 optbl1->mo_count = tmpcnt;
2024 optbl1->mo_list = tmplist;
2025 }
2026
2027 static void
2028 vfs_swapopttbl(mntopts_t *optbl1, mntopts_t *optbl2)
2029 {
2030 vfs_list_lock();
2031 vfs_swapopttbl_nolock(optbl1, optbl2);
2032 vfs_mnttab_modtimeupd();
2033 vfs_list_unlock();
2034 }
2035
2036 static char **
2037 vfs_copycancelopt_extend(char **const moc, int extend)
2038 {
2039 int i = 0;
2040 int j;
2041 char **result;
2042
2043 if (moc != NULL) {
2044 for (; moc[i] != NULL; i++)
2045 /* count number of options to cancel */;
2046 }
2047
2048 if (i + extend == 0)
2049 return (NULL);
2050
2051 result = kmem_alloc((i + extend + 1) * sizeof (char *), KM_SLEEP);
2052
2053 for (j = 0; j < i; j++) {
2054 result[j] = kmem_alloc(strlen(moc[j]) + 1, KM_SLEEP);
2055 (void) strcpy(result[j], moc[j]);
2056 }
2057 for (; j <= i + extend; j++)
2058 result[j] = NULL;
2059
2060 return (result);
2061 }
2062
2063 static void
2064 vfs_copyopt(const mntopt_t *s, mntopt_t *d)
2065 {
2066 char *sp, *dp;
2067
2068 d->mo_flags = s->mo_flags;
2069 d->mo_data = s->mo_data;
2070 sp = s->mo_name;
2071 if (sp != NULL) {
2072 dp = kmem_alloc(strlen(sp) + 1, KM_SLEEP);
2073 (void) strcpy(dp, sp);
2074 d->mo_name = dp;
2075 } else {
2076 d->mo_name = NULL; /* should never happen */
2077 }
2078
2079 d->mo_cancel = vfs_copycancelopt_extend(s->mo_cancel, 0);
2080
2081 sp = s->mo_arg;
2082 if (sp != NULL) {
2083 dp = kmem_alloc(strlen(sp) + 1, KM_SLEEP);
2084 (void) strcpy(dp, sp);
2085 d->mo_arg = dp;
2086 } else {
2087 d->mo_arg = NULL;
2088 }
2089 }
2090
2091 /*
2092 * Copy a mount options table, possibly allocating some spare
2093 * slots at the end. It is permissible to copy_extend the NULL table.
2094 */
2095 static void
2096 vfs_copyopttbl_extend(const mntopts_t *smo, mntopts_t *dmo, int extra)
2097 {
2098 uint_t i, count;
2099 mntopt_t *motbl;
2100
2101 /*
2102 * Clear out any existing stuff in the options table being initialized
2103 */
2104 vfs_freeopttbl(dmo);
2105 count = (smo == NULL) ? 0 : smo->mo_count;
2106 if ((count + extra) == 0) /* nothing to do */
2107 return;
2108 dmo->mo_count = count + extra;
2109 motbl = kmem_zalloc((count + extra) * sizeof (mntopt_t), KM_SLEEP);
2110 dmo->mo_list = motbl;
2111 for (i = 0; i < count; i++) {
2112 vfs_copyopt(&smo->mo_list[i], &motbl[i]);
2113 }
2114 for (i = count; i < count + extra; i++) {
2115 motbl[i].mo_flags = MO_EMPTY;
2116 }
2117 }
2118
2119 /*
2120 * Copy a mount options table.
2121 *
2122 * This function is *not* for general use by filesystems.
2123 *
2124 * Note: caller is responsible for locking the vfs list, if needed,
2125 * to protect smo and dmo.
2126 */
2127 void
2128 vfs_copyopttbl(const mntopts_t *smo, mntopts_t *dmo)
2129 {
2130 vfs_copyopttbl_extend(smo, dmo, 0);
2131 }
2132
2133 static char **
2134 vfs_mergecancelopts(const mntopt_t *mop1, const mntopt_t *mop2)
2135 {
2136 int c1 = 0;
2137 int c2 = 0;
2138 char **result;
2139 char **sp1, **sp2, **dp;
2140
2141 /*
2142 * First we count both lists of cancel options.
2143 * If either is NULL or has no elements, we return a copy of
2144 * the other.
2145 */
2146 if (mop1->mo_cancel != NULL) {
2147 for (; mop1->mo_cancel[c1] != NULL; c1++)
2148 /* count cancel options in mop1 */;
2149 }
2150
2151 if (c1 == 0)
2152 return (vfs_copycancelopt_extend(mop2->mo_cancel, 0));
2153
2154 if (mop2->mo_cancel != NULL) {
2155 for (; mop2->mo_cancel[c2] != NULL; c2++)
2156 /* count cancel options in mop2 */;
2157 }
2158
2159 result = vfs_copycancelopt_extend(mop1->mo_cancel, c2);
2160
2161 if (c2 == 0)
2162 return (result);
2163
2164 /*
2165 * When we get here, we've got two sets of cancel options;
2166 * we need to merge the two sets. We know that the result
2167 * array has "c1+c2+1" entries and in the end we might shrink
2168 * it.
2169 * Result now has a copy of the c1 entries from mop1; we'll
2170 * now lookup all the entries of mop2 in mop1 and copy it if
2171 * it is unique.
2172 * This operation is O(n^2) but it's only called once per
2173 * filesystem per duplicate option. This is a situation
2174 * which doesn't arise with the filesystems in ON and
2175 * n is generally 1.
2176 */
2177
2178 dp = &result[c1];
2179 for (sp2 = mop2->mo_cancel; *sp2 != NULL; sp2++) {
2180 for (sp1 = mop1->mo_cancel; *sp1 != NULL; sp1++) {
2181 if (strcmp(*sp1, *sp2) == 0)
2182 break;
2183 }
2184 if (*sp1 == NULL) {
2185 /*
2186 * Option *sp2 not found in mop1, so copy it.
2187 * The calls to vfs_copycancelopt_extend()
2188 * guarantee that there's enough room.
2189 */
2190 *dp = kmem_alloc(strlen(*sp2) + 1, KM_SLEEP);
2191 (void) strcpy(*dp++, *sp2);
2192 }
2193 }
2194 if (dp != &result[c1+c2]) {
2195 size_t bytes = (dp - result + 1) * sizeof (char *);
2196 char **nres = kmem_alloc(bytes, KM_SLEEP);
2197
2198 bcopy(result, nres, bytes);
2199 kmem_free(result, (c1 + c2 + 1) * sizeof (char *));
2200 result = nres;
2201 }
2202 return (result);
2203 }
2204
2205 /*
2206 * Merge two mount option tables (outer and inner) into one. This is very
2207 * similar to "merging" global variables and automatic variables in C.
2208 *
2209 * This isn't (and doesn't have to be) fast.
2210 *
2211 * This function is *not* for general use by filesystems.
2212 *
2213 * Note: caller is responsible for locking the vfs list, if needed,
2214 * to protect omo, imo & dmo.
2215 */
2216 void
2217 vfs_mergeopttbl(const mntopts_t *omo, const mntopts_t *imo, mntopts_t *dmo)
2218 {
2219 uint_t i, count;
2220 mntopt_t *mop, *motbl;
2221 uint_t freeidx;
2222
2223 /*
2224 * First determine how much space we need to allocate.
2225 */
2226 count = omo->mo_count;
2227 for (i = 0; i < imo->mo_count; i++) {
2228 if (imo->mo_list[i].mo_flags & MO_EMPTY)
2229 continue;
2230 if (vfs_hasopt(omo, imo->mo_list[i].mo_name) == NULL)
2231 count++;
2232 }
2233 ASSERT(count >= omo->mo_count &&
2234 count <= omo->mo_count + imo->mo_count);
2235 motbl = kmem_alloc(count * sizeof (mntopt_t), KM_SLEEP);
2236 for (i = 0; i < omo->mo_count; i++)
2237 vfs_copyopt(&omo->mo_list[i], &motbl[i]);
2238 freeidx = omo->mo_count;
2239 for (i = 0; i < imo->mo_count; i++) {
2240 if (imo->mo_list[i].mo_flags & MO_EMPTY)
2241 continue;
2242 if ((mop = vfs_hasopt(omo, imo->mo_list[i].mo_name)) != NULL) {
2243 char **newcanp;
2244 uint_t index = mop - omo->mo_list;
2245
2246 newcanp = vfs_mergecancelopts(mop, &motbl[index]);
2247
2248 vfs_freeopt(&motbl[index]);
2249 vfs_copyopt(&imo->mo_list[i], &motbl[index]);
2250
2251 vfs_freecancelopt(motbl[index].mo_cancel);
2252 motbl[index].mo_cancel = newcanp;
2253 } else {
2254 /*
2255 * If it's a new option, just copy it over to the first
2256 * free location.
2257 */
2258 vfs_copyopt(&imo->mo_list[i], &motbl[freeidx++]);
2259 }
2260 }
2261 dmo->mo_count = count;
2262 dmo->mo_list = motbl;
2263 }
2264
2265 /*
2266 * Functions to set and clear mount options in a mount options table.
2267 */
2268
2269 /*
2270 * Clear a mount option, if it exists.
2271 *
2272 * The update_mnttab arg indicates whether mops is part of a vfs that is on
2273 * the vfs list.
2274 */
2275 static void
2276 vfs_clearmntopt_nolock(mntopts_t *mops, const char *opt, int update_mnttab)
2277 {
2278 struct mntopt *mop;
2279 uint_t i, count;
2280
2281 ASSERT(!update_mnttab || RW_WRITE_HELD(&vfslist));
2282
2283 count = mops->mo_count;
2284 for (i = 0; i < count; i++) {
2285 mop = &mops->mo_list[i];
2286
2287 if (mop->mo_flags & MO_EMPTY)
2288 continue;
2289 if (strcmp(opt, mop->mo_name))
2290 continue;
2291 mop->mo_flags &= ~MO_SET;
2292 if (mop->mo_arg != NULL) {
2293 kmem_free(mop->mo_arg, strlen(mop->mo_arg) + 1);
2294 }
2295 mop->mo_arg = NULL;
2296 if (update_mnttab)
2297 vfs_mnttab_modtimeupd();
2298 break;
2299 }
2300 }
2301
2302 void
2303 vfs_clearmntopt(struct vfs *vfsp, const char *opt)
2304 {
2305 int gotlock = 0;
2306
2307 if (VFS_ON_LIST(vfsp)) {
2308 gotlock = 1;
2309 vfs_list_lock();
2310 }
2311 vfs_clearmntopt_nolock(&vfsp->vfs_mntopts, opt, gotlock);
2312 if (gotlock)
2313 vfs_list_unlock();
2314 }
2315
2316
2317 /*
2318 * Set a mount option on. If it's not found in the table, it's silently
2319 * ignored. If the option has MO_IGNORE set, it is still set unless the
2320 * VFS_NOFORCEOPT bit is set in the flags. Also, VFS_DISPLAY/VFS_NODISPLAY flag
2321 * bits can be used to toggle the MO_NODISPLAY bit for the option.
2322 * If the VFS_CREATEOPT flag bit is set then the first option slot with
2323 * MO_EMPTY set is created as the option passed in.
2324 *
2325 * The update_mnttab arg indicates whether mops is part of a vfs that is on
2326 * the vfs list.
2327 */
2328 static void
2329 vfs_setmntopt_nolock(mntopts_t *mops, const char *opt,
2330 const char *arg, int flags, int update_mnttab)
2331 {
2332 mntopt_t *mop;
2333 uint_t i, count;
2334 char *sp;
2335
2336 ASSERT(!update_mnttab || RW_WRITE_HELD(&vfslist));
2337
2338 if (flags & VFS_CREATEOPT) {
2339 if (vfs_hasopt(mops, opt) != NULL) {
2340 flags &= ~VFS_CREATEOPT;
2341 }
2342 }
2343 count = mops->mo_count;
2344 for (i = 0; i < count; i++) {
2345 mop = &mops->mo_list[i];
2346
2347 if (mop->mo_flags & MO_EMPTY) {
2348 if ((flags & VFS_CREATEOPT) == 0)
2349 continue;
2350 sp = kmem_alloc(strlen(opt) + 1, KM_SLEEP);
2351 (void) strcpy(sp, opt);
2352 mop->mo_name = sp;
2353 if (arg != NULL)
2354 mop->mo_flags = MO_HASVALUE;
2355 else
2356 mop->mo_flags = 0;
2357 } else if (strcmp(opt, mop->mo_name)) {
2358 continue;
2359 }
2360 if ((mop->mo_flags & MO_IGNORE) && (flags & VFS_NOFORCEOPT))
2361 break;
2362 if (arg != NULL && (mop->mo_flags & MO_HASVALUE) != 0) {
2363 sp = kmem_alloc(strlen(arg) + 1, KM_SLEEP);
2364 (void) strcpy(sp, arg);
2365 } else {
2366 sp = NULL;
2367 }
2368 if (mop->mo_arg != NULL)
2369 kmem_free(mop->mo_arg, strlen(mop->mo_arg) + 1);
2370 mop->mo_arg = sp;
2371 if (flags & VFS_DISPLAY)
2372 mop->mo_flags &= ~MO_NODISPLAY;
2373 if (flags & VFS_NODISPLAY)
2374 mop->mo_flags |= MO_NODISPLAY;
2375 mop->mo_flags |= MO_SET;
2376 if (mop->mo_cancel != NULL) {
2377 char **cp;
2378
2379 for (cp = mop->mo_cancel; *cp != NULL; cp++)
2380 vfs_clearmntopt_nolock(mops, *cp, 0);
2381 }
2382 if (update_mnttab)
2383 vfs_mnttab_modtimeupd();
2384 break;
2385 }
2386 }
2387
2388 void
2389 vfs_setmntopt(struct vfs *vfsp, const char *opt, const char *arg, int flags)
2390 {
2391 int gotlock = 0;
2392
2393 if (VFS_ON_LIST(vfsp)) {
2394 gotlock = 1;
2395 vfs_list_lock();
2396 }
2397 vfs_setmntopt_nolock(&vfsp->vfs_mntopts, opt, arg, flags, gotlock);
2398 if (gotlock)
2399 vfs_list_unlock();
2400 }
2401
2402
2403 /*
2404 * Add a "tag" option to a mounted file system's options list.
2405 *
2406 * Note: caller is responsible for locking the vfs list, if needed,
2407 * to protect mops.
2408 */
2409 static mntopt_t *
2410 vfs_addtag(mntopts_t *mops, const char *tag)
2411 {
2412 uint_t count;
2413 mntopt_t *mop, *motbl;
2414
2415 count = mops->mo_count + 1;
2416 motbl = kmem_zalloc(count * sizeof (mntopt_t), KM_SLEEP);
2417 if (mops->mo_count) {
2418 size_t len = (count - 1) * sizeof (mntopt_t);
2419
2420 bcopy(mops->mo_list, motbl, len);
2421 kmem_free(mops->mo_list, len);
2422 }
2423 mops->mo_count = count;
2424 mops->mo_list = motbl;
2425 mop = &motbl[count - 1];
2426 mop->mo_flags = MO_TAG;
2427 mop->mo_name = kmem_alloc(strlen(tag) + 1, KM_SLEEP);
2428 (void) strcpy(mop->mo_name, tag);
2429 return (mop);
2430 }
2431
2432 /*
2433 * Allow users to set arbitrary "tags" in a vfs's mount options.
2434 * Broader use within the kernel is discouraged.
2435 */
2436 int
2437 vfs_settag(uint_t major, uint_t minor, const char *mntpt, const char *tag,
2438 cred_t *cr)
2439 {
2440 vfs_t *vfsp;
2441 mntopts_t *mops;
2442 mntopt_t *mop;
2443 int found = 0;
2444 dev_t dev = makedevice(major, minor);
2445 int err = 0;
2446 char *buf = kmem_alloc(MAX_MNTOPT_STR, KM_SLEEP);
2447
2448 /*
2449 * Find the desired mounted file system
2450 */
2451 vfs_list_lock();
2452 vfsp = rootvfs;
2453 do {
2454 if (vfsp->vfs_dev == dev &&
2455 strcmp(mntpt, refstr_value(vfsp->vfs_mntpt)) == 0) {
2456 found = 1;
2457 break;
2458 }
2459 vfsp = vfsp->vfs_next;
2460 } while (vfsp != rootvfs);
2461
2462 if (!found) {
2463 err = EINVAL;
2464 goto out;
2465 }
2466 err = secpolicy_fs_config(cr, vfsp);
2467 if (err != 0)
2468 goto out;
2469
2470 mops = &vfsp->vfs_mntopts;
2471 /*
2472 * Add tag if it doesn't already exist
2473 */
2474 if ((mop = vfs_hasopt(mops, tag)) == NULL) {
2475 int len;
2476
2477 (void) vfs_buildoptionstr(mops, buf, MAX_MNTOPT_STR);
2478 len = strlen(buf);
2479 if (len + strlen(tag) + 2 > MAX_MNTOPT_STR) {
2480 err = ENAMETOOLONG;
2481 goto out;
2482 }
2483 mop = vfs_addtag(mops, tag);
2484 }
2485 if ((mop->mo_flags & MO_TAG) == 0) {
2486 err = EINVAL;
2487 goto out;
2488 }
2489 vfs_setmntopt_nolock(mops, tag, NULL, 0, 1);
2490 out:
2491 vfs_list_unlock();
2492 kmem_free(buf, MAX_MNTOPT_STR);
2493 return (err);
2494 }
2495
2496 /*
2497 * Allow users to remove arbitrary "tags" in a vfs's mount options.
2498 * Broader use within the kernel is discouraged.
2499 */
2500 int
2501 vfs_clrtag(uint_t major, uint_t minor, const char *mntpt, const char *tag,
2502 cred_t *cr)
2503 {
2504 vfs_t *vfsp;
2505 mntopt_t *mop;
2506 int found = 0;
2507 dev_t dev = makedevice(major, minor);
2508 int err = 0;
2509
2510 /*
2511 * Find the desired mounted file system
2512 */
2513 vfs_list_lock();
2514 vfsp = rootvfs;
2515 do {
2516 if (vfsp->vfs_dev == dev &&
2517 strcmp(mntpt, refstr_value(vfsp->vfs_mntpt)) == 0) {
2518 found = 1;
2519 break;
2520 }
2521 vfsp = vfsp->vfs_next;
2522 } while (vfsp != rootvfs);
2523
2524 if (!found) {
2525 err = EINVAL;
2526 goto out;
2527 }
2528 err = secpolicy_fs_config(cr, vfsp);
2529 if (err != 0)
2530 goto out;
2531
2532 if ((mop = vfs_hasopt(&vfsp->vfs_mntopts, tag)) == NULL) {
2533 err = EINVAL;
2534 goto out;
2535 }
2536 if ((mop->mo_flags & MO_TAG) == 0) {
2537 err = EINVAL;
2538 goto out;
2539 }
2540 vfs_clearmntopt_nolock(&vfsp->vfs_mntopts, tag, 1);
2541 out:
2542 vfs_list_unlock();
2543 return (err);
2544 }
2545
2546 /*
2547 * Function to parse an option string and fill in a mount options table.
2548 * Unknown options are silently ignored. The input option string is modified
2549 * by replacing separators with nulls. If the create flag is set, options
2550 * not found in the table are just added on the fly. The table must have
2551 * an option slot marked MO_EMPTY to add an option on the fly.
2552 *
2553 * This function is *not* for general use by filesystems.
2554 *
2555 * Note: caller is responsible for locking the vfs list, if needed,
2556 * to protect mops..
2557 */
2558 void
2559 vfs_parsemntopts(mntopts_t *mops, char *osp, int create)
2560 {
2561 char *s = osp, *p, *nextop, *valp, *cp, *ep;
2562 int setflg = VFS_NOFORCEOPT;
2563
2564 if (osp == NULL)
2565 return;
2566 while (*s != '\0') {
2567 p = strchr(s, ','); /* find next option */
2568 if (p == NULL) {
2569 cp = NULL;
2570 p = s + strlen(s);
2571 } else {
2572 cp = p; /* save location of comma */
2573 *p++ = '\0'; /* mark end and point to next option */
2574 }
2575 nextop = p;
2576 p = strchr(s, '='); /* look for value */
2577 if (p == NULL) {
2578 valp = NULL; /* no value supplied */
2579 } else {
2580 ep = p; /* save location of equals */
2581 *p++ = '\0'; /* end option and point to value */
2582 valp = p;
2583 }
2584 /*
2585 * set option into options table
2586 */
2587 if (create)
2588 setflg |= VFS_CREATEOPT;
2589 vfs_setmntopt_nolock(mops, s, valp, setflg, 0);
2590 if (cp != NULL)
2591 *cp = ','; /* restore the comma */
2592 if (valp != NULL)
2593 *ep = '='; /* restore the equals */
2594 s = nextop;
2595 }
2596 }
2597
2598 /*
2599 * Function to inquire if an option exists in a mount options table.
2600 * Returns a pointer to the option if it exists, else NULL.
2601 *
2602 * This function is *not* for general use by filesystems.
2603 *
2604 * Note: caller is responsible for locking the vfs list, if needed,
2605 * to protect mops.
2606 */
2607 struct mntopt *
2608 vfs_hasopt(const mntopts_t *mops, const char *opt)
2609 {
2610 struct mntopt *mop;
2611 uint_t i, count;
2612
2613 count = mops->mo_count;
2614 for (i = 0; i < count; i++) {
2615 mop = &mops->mo_list[i];
2616
2617 if (mop->mo_flags & MO_EMPTY)
2618 continue;
2619 if (strcmp(opt, mop->mo_name) == 0)
2620 return (mop);
2621 }
2622 return (NULL);
2623 }
2624
2625 /*
2626 * Function to inquire if an option is set in a mount options table.
2627 * Returns non-zero if set and fills in the arg pointer with a pointer to
2628 * the argument string or NULL if there is no argument string.
2629 */
2630 static int
2631 vfs_optionisset_nolock(const mntopts_t *mops, const char *opt, char **argp)
2632 {
2633 struct mntopt *mop;
2634 uint_t i, count;
2635
2636 count = mops->mo_count;
2637 for (i = 0; i < count; i++) {
2638 mop = &mops->mo_list[i];
2639
2640 if (mop->mo_flags & MO_EMPTY)
2641 continue;
2642 if (strcmp(opt, mop->mo_name))
2643 continue;
2644 if ((mop->mo_flags & MO_SET) == 0)
2645 return (0);
2646 if (argp != NULL && (mop->mo_flags & MO_HASVALUE) != 0)
2647 *argp = mop->mo_arg;
2648 return (1);
2649 }
2650 return (0);
2651 }
2652
2653
2654 int
2655 vfs_optionisset(const struct vfs *vfsp, const char *opt, char **argp)
2656 {
2657 int ret;
2658
2659 vfs_list_read_lock();
2660 ret = vfs_optionisset_nolock(&vfsp->vfs_mntopts, opt, argp);
2661 vfs_list_unlock();
2662 return (ret);
2663 }
2664
2665
2666 /*
2667 * Construct a comma separated string of the options set in the given
2668 * mount table, return the string in the given buffer. Return non-zero if
2669 * the buffer would overflow.
2670 *
2671 * This function is *not* for general use by filesystems.
2672 *
2673 * Note: caller is responsible for locking the vfs list, if needed,
2674 * to protect mp.
2675 */
2676 int
2677 vfs_buildoptionstr(const mntopts_t *mp, char *buf, int len)
2678 {
2679 char *cp;
2680 uint_t i;
2681
2682 buf[0] = '\0';
2683 cp = buf;
2684 for (i = 0; i < mp->mo_count; i++) {
2685 struct mntopt *mop;
2686
2687 mop = &mp->mo_list[i];
2688 if (mop->mo_flags & MO_SET) {
2689 int optlen, comma = 0;
2690
2691 if (buf[0] != '\0')
2692 comma = 1;
2693 optlen = strlen(mop->mo_name);
2694 if (strlen(buf) + comma + optlen + 1 > len)
2695 goto err;
2696 if (comma)
2697 *cp++ = ',';
2698 (void) strcpy(cp, mop->mo_name);
2699 cp += optlen;
2700 /*
2701 * Append option value if there is one
2702 */
2703 if (mop->mo_arg != NULL) {
2704 int arglen;
2705
2706 arglen = strlen(mop->mo_arg);
2707 if (strlen(buf) + arglen + 2 > len)
2708 goto err;
2709 *cp++ = '=';
2710 (void) strcpy(cp, mop->mo_arg);
2711 cp += arglen;
2712 }
2713 }
2714 }
2715 return (0);
2716 err:
2717 return (EOVERFLOW);
2718 }
2719
2720 static void
2721 vfs_freecancelopt(char **moc)
2722 {
2723 if (moc != NULL) {
2724 int ccnt = 0;
2725 char **cp;
2726
2727 for (cp = moc; *cp != NULL; cp++) {
2728 kmem_free(*cp, strlen(*cp) + 1);
2729 ccnt++;
2730 }
2731 kmem_free(moc, (ccnt + 1) * sizeof (char *));
2732 }
2733 }
2734
2735 static void
2736 vfs_freeopt(mntopt_t *mop)
2737 {
2738 if (mop->mo_name != NULL)
2739 kmem_free(mop->mo_name, strlen(mop->mo_name) + 1);
2740
2741 vfs_freecancelopt(mop->mo_cancel);
2742
2743 if (mop->mo_arg != NULL)
2744 kmem_free(mop->mo_arg, strlen(mop->mo_arg) + 1);
2745 }
2746
2747 /*
2748 * Free a mount options table
2749 *
2750 * This function is *not* for general use by filesystems.
2751 *
2752 * Note: caller is responsible for locking the vfs list, if needed,
2753 * to protect mp.
2754 */
2755 void
2756 vfs_freeopttbl(mntopts_t *mp)
2757 {
2758 uint_t i, count;
2759
2760 count = mp->mo_count;
2761 for (i = 0; i < count; i++) {
2762 vfs_freeopt(&mp->mo_list[i]);
2763 }
2764 if (count) {
2765 kmem_free(mp->mo_list, sizeof (mntopt_t) * count);
2766 mp->mo_count = 0;
2767 mp->mo_list = NULL;
2768 }
2769 }
2770
2771
2772 /* ARGSUSED */
2773 static int
2774 vfs_mntdummyread(vnode_t *vp, uio_t *uio, int ioflag, cred_t *cred,
2775 caller_context_t *ct)
2776 {
2777 return (0);
2778 }
2779
2780 /* ARGSUSED */
2781 static int
2782 vfs_mntdummywrite(vnode_t *vp, uio_t *uio, int ioflag, cred_t *cred,
2783 caller_context_t *ct)
2784 {
2785 return (0);
2786 }
2787
2788 /*
2789 * The dummy vnode is currently used only by file events notification
2790 * module which is just interested in the timestamps.
2791 */
2792 /* ARGSUSED */
2793 static int
2794 vfs_mntdummygetattr(vnode_t *vp, vattr_t *vap, int flags, cred_t *cr,
2795 caller_context_t *ct)
2796 {
2797 bzero(vap, sizeof (vattr_t));
2798 vap->va_type = VREG;
2799 vap->va_nlink = 1;
2800 vap->va_ctime = vfs_mnttab_ctime;
2801 /*
2802 * it is ok to just copy mtime as the time will be monotonically
2803 * increasing.
2804 */
2805 vap->va_mtime = vfs_mnttab_mtime;
2806 vap->va_atime = vap->va_mtime;
2807 return (0);
2808 }
2809
2810 static void
2811 vfs_mnttabvp_setup(void)
2812 {
2813 vnode_t *tvp;
2814 vnodeops_t *vfs_mntdummyvnops;
2815 const fs_operation_def_t mnt_dummyvnodeops_template[] = {
2816 VOPNAME_READ, { .vop_read = vfs_mntdummyread },
2817 VOPNAME_WRITE, { .vop_write = vfs_mntdummywrite },
2818 VOPNAME_GETATTR, { .vop_getattr = vfs_mntdummygetattr },
2819 VOPNAME_VNEVENT, { .vop_vnevent = fs_vnevent_support },
2820 NULL, NULL
2821 };
2822
2823 if (vn_make_ops("mnttab", mnt_dummyvnodeops_template,
2824 &vfs_mntdummyvnops) != 0) {
2825 cmn_err(CE_WARN, "vfs_mnttabvp_setup: vn_make_ops failed");
2826 /* Shouldn't happen, but not bad enough to panic */
2827 return;
2828 }
2829
2830 /*
2831 * A global dummy vnode is allocated to represent mntfs files.
2832 * The mntfs file (/etc/mnttab) can be monitored for file events
2833 * and receive an event when mnttab changes. Dummy VOP calls
2834 * will be made on this vnode. The file events notification module
2835 * intercepts this vnode and delivers relevant events.
2836 */
2837 tvp = vn_alloc(KM_SLEEP);
2838 tvp->v_flag = VNOMOUNT|VNOMAP|VNOSWAP|VNOCACHE;
2839 vn_setops(tvp, vfs_mntdummyvnops);
2840 tvp->v_type = VREG;
2841 /*
2842 * The mnt dummy ops do not reference v_data.
2843 * No other module intercepting this vnode should either.
2844 * Just set it to point to itself.
2845 */
2846 tvp->v_data = (caddr_t)tvp;
2847 tvp->v_vfsp = rootvfs;
2848 vfs_mntdummyvp = tvp;
2849 }
2850
2851 /*
2852 * performs fake read/write ops
2853 */
2854 static void
2855 vfs_mnttab_rwop(int rw)
2856 {
2857 struct uio uio;
2858 struct iovec iov;
2859 char buf[1];
2860
2861 if (vfs_mntdummyvp == NULL)
2862 return;
2863
2864 bzero(&uio, sizeof (uio));
2865 bzero(&iov, sizeof (iov));
2866 iov.iov_base = buf;
2867 iov.iov_len = 0;
2868 uio.uio_iov = &iov;
2869 uio.uio_iovcnt = 1;
2870 uio.uio_loffset = 0;
2871 uio.uio_segflg = UIO_SYSSPACE;
2872 uio.uio_resid = 0;
2873 if (rw) {
2874 (void) VOP_WRITE(vfs_mntdummyvp, &uio, 0, kcred, NULL);
2875 } else {
2876 (void) VOP_READ(vfs_mntdummyvp, &uio, 0, kcred, NULL);
2877 }
2878 }
2879
2880 /*
2881 * Generate a write operation.
2882 */
2883 void
2884 vfs_mnttab_writeop(void)
2885 {
2886 vfs_mnttab_rwop(1);
2887 }
2888
2889 /*
2890 * Generate a read operation.
2891 */
2892 void
2893 vfs_mnttab_readop(void)
2894 {
2895 vfs_mnttab_rwop(0);
2896 }
2897
2898 /*
2899 * Free any mnttab information recorded in the vfs struct.
2900 * The vfs must not be on the vfs list.
2901 */
2902 static void
2903 vfs_freemnttab(struct vfs *vfsp)
2904 {
2905 ASSERT(!VFS_ON_LIST(vfsp));
2906
2907 /*
2908 * Free device and mount point information
2909 */
2910 if (vfsp->vfs_mntpt != NULL) {
2911 refstr_rele(vfsp->vfs_mntpt);
2912 vfsp->vfs_mntpt = NULL;
2913 }
2914 if (vfsp->vfs_resource != NULL) {
2915 refstr_rele(vfsp->vfs_resource);
2916 vfsp->vfs_resource = NULL;
2917 }
2918 /*
2919 * Now free mount options information
2920 */
2921 vfs_freeopttbl(&vfsp->vfs_mntopts);
2922 }
2923
2924 /*
2925 * Return the last mnttab modification time
2926 */
2927 void
2928 vfs_mnttab_modtime(timespec_t *ts)
2929 {
2930 ASSERT(RW_LOCK_HELD(&vfslist));
2931 *ts = vfs_mnttab_mtime;
2932 }
2933
2934 /*
2935 * See if mnttab is changed
2936 */
2937 void
2938 vfs_mnttab_poll(timespec_t *old, struct pollhead **phpp)
2939 {
2940 int changed;
2941
2942 *phpp = (struct pollhead *)NULL;
2943
2944 /*
2945 * Note: don't grab vfs list lock before accessing vfs_mnttab_mtime.
2946 * Can lead to deadlock against vfs_mnttab_modtimeupd(). It is safe
2947 * to not grab the vfs list lock because tv_sec is monotonically
2948 * increasing.
2949 */
2950
2951 changed = (old->tv_nsec != vfs_mnttab_mtime.tv_nsec) ||
2952 (old->tv_sec != vfs_mnttab_mtime.tv_sec);
2953 if (!changed) {
2954 *phpp = &vfs_pollhd;
2955 }
2956 }
2957
2958 /* Provide a unique and monotonically-increasing timestamp. */
2959 void
2960 vfs_mono_time(timespec_t *ts)
2961 {
2962 static volatile hrtime_t hrt; /* The saved time. */
2963 hrtime_t newhrt, oldhrt; /* For effecting the CAS. */
2964 timespec_t newts;
2965
2966 /*
2967 * Try gethrestime() first, but be prepared to fabricate a sensible
2968 * answer at the first sign of any trouble.
2969 */
2970 gethrestime(&newts);
2971 newhrt = ts2hrt(&newts);
2972 for (;;) {
2973 oldhrt = hrt;
2974 if (newhrt <= hrt)
2975 newhrt = hrt + 1;
2976 if (atomic_cas_64((uint64_t *)&hrt, oldhrt, newhrt) == oldhrt)
2977 break;
2978 }
2979 hrt2ts(newhrt, ts);
2980 }
2981
2982 /*
2983 * Update the mnttab modification time and wake up any waiters for
2984 * mnttab changes
2985 */
2986 void
2987 vfs_mnttab_modtimeupd()
2988 {
2989 hrtime_t oldhrt, newhrt;
2990
2991 ASSERT(RW_WRITE_HELD(&vfslist));
2992 oldhrt = ts2hrt(&vfs_mnttab_mtime);
2993 gethrestime(&vfs_mnttab_mtime);
2994 newhrt = ts2hrt(&vfs_mnttab_mtime);
2995 if (oldhrt == (hrtime_t)0)
2996 vfs_mnttab_ctime = vfs_mnttab_mtime;
2997 /*
2998 * Attempt to provide unique mtime (like uniqtime but not).
2999 */
3000 if (newhrt == oldhrt) {
3001 newhrt++;
3002 hrt2ts(newhrt, &vfs_mnttab_mtime);
3003 }
3004 pollwakeup(&vfs_pollhd, (short)POLLRDBAND);
3005 vfs_mnttab_writeop();
3006 }
3007
3008 int
3009 dounmount(struct vfs *vfsp, int flag, cred_t *cr)
3010 {
3011 vnode_t *coveredvp;
3012 int error;
3013 extern void teardown_vopstats(vfs_t *);
3014
3015 /*
3016 * Get covered vnode. This will be NULL if the vfs is not linked
3017 * into the file system name space (i.e., domount() with MNT_NOSPICE).
3018 */
3019 coveredvp = vfsp->vfs_vnodecovered;
3020 ASSERT(coveredvp == NULL || vn_vfswlock_held(coveredvp));
3021
3022 /*
3023 * Purge all dnlc entries for this vfs.
3024 */
3025 (void) dnlc_purge_vfsp(vfsp, 0);
3026
3027 /* For forcible umount, skip VFS_SYNC() since it may hang */
3028 if ((flag & MS_FORCE) == 0)
3029 (void) VFS_SYNC(vfsp, 0, cr);
3030
3031 /*
3032 * Lock the vfs to maintain fs status quo during unmount. This
3033 * has to be done after the sync because ufs_update tries to acquire
3034 * the vfs_reflock.
3035 */
3036 vfs_lock_wait(vfsp);
3037
3038 if (error = VFS_UNMOUNT(vfsp, flag, cr)) {
3039 vfs_unlock(vfsp);
3040 if (coveredvp != NULL)
3041 vn_vfsunlock(coveredvp);
3042 } else if (coveredvp != NULL) {
3043 teardown_vopstats(vfsp);
3044 /*
3045 * vfs_remove() will do a VN_RELE(vfsp->vfs_vnodecovered)
3046 * when it frees vfsp so we do a VN_HOLD() so we can
3047 * continue to use coveredvp afterwards.
3048 */
3049 VN_HOLD(coveredvp);
3050 vfs_remove(vfsp);
3051 vn_vfsunlock(coveredvp);
3052 VN_RELE(coveredvp);
3053 } else {
3054 teardown_vopstats(vfsp);
3055 /*
3056 * Release the reference to vfs that is not linked
3057 * into the name space.
3058 */
3059 vfs_unlock(vfsp);
3060 VFS_RELE(vfsp);
3061 }
3062 return (error);
3063 }
3064
3065
3066 /*
3067 * Vfs_unmountall() is called by uadmin() to unmount all
3068 * mounted file systems (except the root file system) during shutdown.
3069 * It follows the existing locking protocol when traversing the vfs list
3070 * to sync and unmount vfses. Even though there should be no
3071 * other thread running while the system is shutting down, it is prudent
3072 * to still follow the locking protocol.
3073 */
3074 void
3075 vfs_unmountall(void)
3076 {
3077 struct vfs *vfsp;
3078 struct vfs *prev_vfsp = NULL;
3079 int error;
3080
3081 /*
3082 * Toss all dnlc entries now so that the per-vfs sync
3083 * and unmount operations don't have to slog through
3084 * a bunch of uninteresting vnodes over and over again.
3085 */
3086 dnlc_purge();
3087
3088 vfs_list_lock();
3089 for (vfsp = rootvfs->vfs_prev; vfsp != rootvfs; vfsp = prev_vfsp) {
3090 prev_vfsp = vfsp->vfs_prev;
3091
3092 if (vfs_lock(vfsp) != 0)
3093 continue;
3094 error = vn_vfswlock(vfsp->vfs_vnodecovered);
3095 vfs_unlock(vfsp);
3096 if (error)
3097 continue;
3098
3099 vfs_list_unlock();
3100
3101 (void) VFS_SYNC(vfsp, SYNC_CLOSE, CRED());
3102 (void) dounmount(vfsp, 0, CRED());
3103
3104 /*
3105 * Since we dropped the vfslist lock above we must
3106 * verify that next_vfsp still exists, else start over.
3107 */
3108 vfs_list_lock();
3109 for (vfsp = rootvfs->vfs_prev;
3110 vfsp != rootvfs; vfsp = vfsp->vfs_prev)
3111 if (vfsp == prev_vfsp)
3112 break;
3113 if (vfsp == rootvfs && prev_vfsp != rootvfs)
3114 prev_vfsp = rootvfs->vfs_prev;
3115 }
3116 vfs_list_unlock();
3117 }
3118
3119 /*
3120 * Called to add an entry to the end of the vfs mount in progress list
3121 */
3122 void
3123 vfs_addmip(dev_t dev, struct vfs *vfsp)
3124 {
3125 struct ipmnt *mipp;
3126
3127 mipp = (struct ipmnt *)kmem_alloc(sizeof (struct ipmnt), KM_SLEEP);
3128 mipp->mip_next = NULL;
3129 mipp->mip_dev = dev;
3130 mipp->mip_vfsp = vfsp;
3131 mutex_enter(&vfs_miplist_mutex);
3132 if (vfs_miplist_end != NULL)
3133 vfs_miplist_end->mip_next = mipp;
3134 else
3135 vfs_miplist = mipp;
3136 vfs_miplist_end = mipp;
3137 mutex_exit(&vfs_miplist_mutex);
3138 }
3139
3140 /*
3141 * Called to remove an entry from the mount in progress list
3142 * Either because the mount completed or it failed.
3143 */
3144 void
3145 vfs_delmip(struct vfs *vfsp)
3146 {
3147 struct ipmnt *mipp, *mipprev;
3148
3149 mutex_enter(&vfs_miplist_mutex);
3150 mipprev = NULL;
3151 for (mipp = vfs_miplist;
3152 mipp && mipp->mip_vfsp != vfsp; mipp = mipp->mip_next) {
3153 mipprev = mipp;
3154 }
3155 if (mipp == NULL)
3156 return; /* shouldn't happen */
3157 if (mipp == vfs_miplist_end)
3158 vfs_miplist_end = mipprev;
3159 if (mipprev == NULL)
3160 vfs_miplist = mipp->mip_next;
3161 else
3162 mipprev->mip_next = mipp->mip_next;
3163 mutex_exit(&vfs_miplist_mutex);
3164 kmem_free(mipp, sizeof (struct ipmnt));
3165 }
3166
3167 /*
3168 * vfs_add is called by a specific filesystem's mount routine to add
3169 * the new vfs into the vfs list/hash and to cover the mounted-on vnode.
3170 * The vfs should already have been locked by the caller.
3171 *
3172 * coveredvp is NULL if this is the root.
3173 */
3174 void
3175 vfs_add(vnode_t *coveredvp, struct vfs *vfsp, int mflag)
3176 {
3177 int newflag;
3178
3179 ASSERT(vfs_lock_held(vfsp));
3180 VFS_HOLD(vfsp);
3181 newflag = vfsp->vfs_flag;
3182 if (mflag & MS_RDONLY)
3183 newflag |= VFS_RDONLY;
3184 else
3185 newflag &= ~VFS_RDONLY;
3186 if (mflag & MS_NOSUID)
3187 newflag |= (VFS_NOSETUID|VFS_NODEVICES);
3188 else
3189 newflag &= ~(VFS_NOSETUID|VFS_NODEVICES);
3190 if (mflag & MS_NOMNTTAB)
3191 newflag |= VFS_NOMNTTAB;
3192 else
3193 newflag &= ~VFS_NOMNTTAB;
3194
3195 if (coveredvp != NULL) {
3196 ASSERT(vn_vfswlock_held(coveredvp));
3197 coveredvp->v_vfsmountedhere = vfsp;
3198 VN_HOLD(coveredvp);
3199 }
3200 vfsp->vfs_vnodecovered = coveredvp;
3201 vfsp->vfs_flag = newflag;
3202
3203 vfs_list_add(vfsp);
3204 }
3205
3206 /*
3207 * Remove a vfs from the vfs list, null out the pointer from the
3208 * covered vnode to the vfs (v_vfsmountedhere), and null out the pointer
3209 * from the vfs to the covered vnode (vfs_vnodecovered). Release the
3210 * reference to the vfs and to the covered vnode.
3211 *
3212 * Called from dounmount after it's confirmed with the file system
3213 * that the unmount is legal.
3214 */
3215 void
3216 vfs_remove(struct vfs *vfsp)
3217 {
3218 vnode_t *vp;
3219
3220 ASSERT(vfs_lock_held(vfsp));
3221
3222 /*
3223 * Can't unmount root. Should never happen because fs will
3224 * be busy.
3225 */
3226 if (vfsp == rootvfs)
3227 panic("vfs_remove: unmounting root");
3228
3229 vfs_list_remove(vfsp);
3230
3231 /*
3232 * Unhook from the file system name space.
3233 */
3234 vp = vfsp->vfs_vnodecovered;
3235 ASSERT(vn_vfswlock_held(vp));
3236 vp->v_vfsmountedhere = NULL;
3237 vfsp->vfs_vnodecovered = NULL;
3238 VN_RELE(vp);
3239
3240 /*
3241 * Release lock and wakeup anybody waiting.
3242 */
3243 vfs_unlock(vfsp);
3244 VFS_RELE(vfsp);
3245 }
3246
3247 /*
3248 * Lock a filesystem to prevent access to it while mounting,
3249 * unmounting and syncing. Return EBUSY immediately if lock
3250 * can't be acquired.
3251 */
3252 int
3253 vfs_lock(vfs_t *vfsp)
3254 {
3255 vn_vfslocks_entry_t *vpvfsentry;
3256
3257 vpvfsentry = vn_vfslocks_getlock(vfsp);
3258 if (rwst_tryenter(&vpvfsentry->ve_lock, RW_WRITER))
3259 return (0);
3260
3261 vn_vfslocks_rele(vpvfsentry);
3262 return (EBUSY);
3263 }
3264
3265 int
3266 vfs_rlock(vfs_t *vfsp)
3267 {
3268 vn_vfslocks_entry_t *vpvfsentry;
3269
3270 vpvfsentry = vn_vfslocks_getlock(vfsp);
3271
3272 if (rwst_tryenter(&vpvfsentry->ve_lock, RW_READER))
3273 return (0);
3274
3275 vn_vfslocks_rele(vpvfsentry);
3276 return (EBUSY);
3277 }
3278
3279 void
3280 vfs_lock_wait(vfs_t *vfsp)
3281 {
3282 vn_vfslocks_entry_t *vpvfsentry;
3283
3284 vpvfsentry = vn_vfslocks_getlock(vfsp);
3285 rwst_enter(&vpvfsentry->ve_lock, RW_WRITER);
3286 }
3287
3288 void
3289 vfs_rlock_wait(vfs_t *vfsp)
3290 {
3291 vn_vfslocks_entry_t *vpvfsentry;
3292
3293 vpvfsentry = vn_vfslocks_getlock(vfsp);
3294 rwst_enter(&vpvfsentry->ve_lock, RW_READER);
3295 }
3296
3297 /*
3298 * Unlock a locked filesystem.
3299 */
3300 void
3301 vfs_unlock(vfs_t *vfsp)
3302 {
3303 vn_vfslocks_entry_t *vpvfsentry;
3304
3305 /*
3306 * vfs_unlock will mimic sema_v behaviour to fix 4748018.
3307 * And these changes should remain for the patch changes as it is.
3308 */
3309 if (panicstr)
3310 return;
3311
3312 /*
3313 * ve_refcount needs to be dropped twice here.
3314 * 1. To release refernce after a call to vfs_locks_getlock()
3315 * 2. To release the reference from the locking routines like
3316 * vfs_rlock_wait/vfs_wlock_wait/vfs_wlock etc,.
3317 */
3318
3319 vpvfsentry = vn_vfslocks_getlock(vfsp);
3320 vn_vfslocks_rele(vpvfsentry);
3321
3322 rwst_exit(&vpvfsentry->ve_lock);
3323 vn_vfslocks_rele(vpvfsentry);
3324 }
3325
3326 /*
3327 * Utility routine that allows a filesystem to construct its
3328 * fsid in "the usual way" - by munging some underlying dev_t and
3329 * the filesystem type number into the 64-bit fsid. Note that
3330 * this implicitly relies on dev_t persistence to make filesystem
3331 * id's persistent.
3332 *
3333 * There's nothing to prevent an individual fs from constructing its
3334 * fsid in a different way, and indeed they should.
3335 *
3336 * Since we want fsids to be 32-bit quantities (so that they can be
3337 * exported identically by either 32-bit or 64-bit APIs, as well as
3338 * the fact that fsid's are "known" to NFS), we compress the device
3339 * number given down to 32-bits, and panic if that isn't possible.
3340 */
3341 void
3342 vfs_make_fsid(fsid_t *fsi, dev_t dev, int val)
3343 {
3344 if (!cmpldev((dev32_t *)&fsi->val[0], dev))
3345 panic("device number too big for fsid!");
3346 fsi->val[1] = val;
3347 }
3348
3349 int
3350 vfs_lock_held(vfs_t *vfsp)
3351 {
3352 int held;
3353 vn_vfslocks_entry_t *vpvfsentry;
3354
3355 /*
3356 * vfs_lock_held will mimic sema_held behaviour
3357 * if panicstr is set. And these changes should remain
3358 * for the patch changes as it is.
3359 */
3360 if (panicstr)
3361 return (1);
3362
3363 vpvfsentry = vn_vfslocks_getlock(vfsp);
3364 held = rwst_lock_held(&vpvfsentry->ve_lock, RW_WRITER);
3365
3366 vn_vfslocks_rele(vpvfsentry);
3367 return (held);
3368 }
3369
3370 struct _kthread *
3371 vfs_lock_owner(vfs_t *vfsp)
3372 {
3373 struct _kthread *owner;
3374 vn_vfslocks_entry_t *vpvfsentry;
3375
3376 /*
3377 * vfs_wlock_held will mimic sema_held behaviour
3378 * if panicstr is set. And these changes should remain
3379 * for the patch changes as it is.
3380 */
3381 if (panicstr)
3382 return (NULL);
3383
3384 vpvfsentry = vn_vfslocks_getlock(vfsp);
3385 owner = rwst_owner(&vpvfsentry->ve_lock);
3386
3387 vn_vfslocks_rele(vpvfsentry);
3388 return (owner);
3389 }
3390
3391 /*
3392 * vfs list locking.
3393 *
3394 * Rather than manipulate the vfslist lock directly, we abstract into lock
3395 * and unlock routines to allow the locking implementation to be changed for
3396 * clustering.
3397 *
3398 * Whenever the vfs list is modified through its hash links, the overall list
3399 * lock must be obtained before locking the relevant hash bucket. But to see
3400 * whether a given vfs is on the list, it suffices to obtain the lock for the
3401 * hash bucket without getting the overall list lock. (See getvfs() below.)
3402 */
3403
3404 void
3405 vfs_list_lock()
3406 {
3407 rw_enter(&vfslist, RW_WRITER);
3408 }
3409
3410 void
3411 vfs_list_read_lock()
3412 {
3413 rw_enter(&vfslist, RW_READER);
3414 }
3415
3416 void
3417 vfs_list_unlock()
3418 {
3419 rw_exit(&vfslist);
3420 }
3421
3422 /*
3423 * Low level worker routines for adding entries to and removing entries from
3424 * the vfs list.
3425 */
3426
3427 static void
3428 vfs_hash_add(struct vfs *vfsp, int insert_at_head)
3429 {
3430 int vhno;
3431 struct vfs **hp;
3432 dev_t dev;
3433
3434 ASSERT(RW_WRITE_HELD(&vfslist));
3435
3436 dev = expldev(vfsp->vfs_fsid.val[0]);
3437 vhno = VFSHASH(getmajor(dev), getminor(dev));
3438
3439 mutex_enter(&rvfs_list[vhno].rvfs_lock);
3440
3441 /*
3442 * Link into the hash table, inserting it at the end, so that LOFS
3443 * with the same fsid as UFS (or other) file systems will not hide the
3444 * UFS.
3445 */
3446 if (insert_at_head) {
3447 vfsp->vfs_hash = rvfs_list[vhno].rvfs_head;
3448 rvfs_list[vhno].rvfs_head = vfsp;
3449 } else {
3450 for (hp = &rvfs_list[vhno].rvfs_head; *hp != NULL;
3451 hp = &(*hp)->vfs_hash)
3452 continue;
3453 /*
3454 * hp now contains the address of the pointer to update
3455 * to effect the insertion.
3456 */
3457 vfsp->vfs_hash = NULL;
3458 *hp = vfsp;
3459 }
3460
3461 rvfs_list[vhno].rvfs_len++;
3462 mutex_exit(&rvfs_list[vhno].rvfs_lock);
3463 }
3464
3465
3466 static void
3467 vfs_hash_remove(struct vfs *vfsp)
3468 {
3469 int vhno;
3470 struct vfs *tvfsp;
3471 dev_t dev;
3472
3473 ASSERT(RW_WRITE_HELD(&vfslist));
3474
3475 dev = expldev(vfsp->vfs_fsid.val[0]);
3476 vhno = VFSHASH(getmajor(dev), getminor(dev));
3477
3478 mutex_enter(&rvfs_list[vhno].rvfs_lock);
3479
3480 /*
3481 * Remove from hash.
3482 */
3483 if (rvfs_list[vhno].rvfs_head == vfsp) {
3484 rvfs_list[vhno].rvfs_head = vfsp->vfs_hash;
3485 rvfs_list[vhno].rvfs_len--;
3486 goto foundit;
3487 }
3488 for (tvfsp = rvfs_list[vhno].rvfs_head; tvfsp != NULL;
3489 tvfsp = tvfsp->vfs_hash) {
3490 if (tvfsp->vfs_hash == vfsp) {
3491 tvfsp->vfs_hash = vfsp->vfs_hash;
3492 rvfs_list[vhno].rvfs_len--;
3493 goto foundit;
3494 }
3495 }
3496 cmn_err(CE_WARN, "vfs_list_remove: vfs not found in hash");
3497
3498 foundit:
3499
3500 mutex_exit(&rvfs_list[vhno].rvfs_lock);
3501 }
3502
3503
3504 void
3505 vfs_list_add(struct vfs *vfsp)
3506 {
3507 zone_t *zone;
3508
3509 /*
3510 * Typically, the vfs_t will have been created on behalf of the file
3511 * system in vfs_init, where it will have been provided with a
3512 * vfs_impl_t. This, however, might be lacking if the vfs_t was created
3513 * by an unbundled file system. We therefore check for such an example
3514 * before stamping the vfs_t with its creation time for the benefit of
3515 * mntfs.
3516 */
3517 if (vfsp->vfs_implp == NULL)
3518 vfsimpl_setup(vfsp);
3519 vfs_mono_time(&vfsp->vfs_hrctime);
3520
3521 /*
3522 * The zone that owns the mount is the one that performed the mount.
3523 * Note that this isn't necessarily the same as the zone mounted into.
3524 * The corresponding zone_rele_ref() will be done when the vfs_t
3525 * is being free'd.
3526 */
3527 vfsp->vfs_zone = curproc->p_zone;
3528 zone_init_ref(&vfsp->vfs_implp->vi_zone_ref);
3529 zone_hold_ref(vfsp->vfs_zone, &vfsp->vfs_implp->vi_zone_ref,
3530 ZONE_REF_VFS);
3531
3532 /*
3533 * Find the zone mounted into, and put this mount on its vfs list.
3534 */
3535 zone = zone_find_by_path(refstr_value(vfsp->vfs_mntpt));
3536 ASSERT(zone != NULL);
3537 /*
3538 * Special casing for the root vfs. This structure is allocated
3539 * statically and hooked onto rootvfs at link time. During the
3540 * vfs_mountroot call at system startup time, the root file system's
3541 * VFS_MOUNTROOT routine will call vfs_add with this root vfs struct
3542 * as argument. The code below must detect and handle this special
3543 * case. The only apparent justification for this special casing is
3544 * to ensure that the root file system appears at the head of the
3545 * list.
3546 *
3547 * XXX: I'm assuming that it's ok to do normal list locking when
3548 * adding the entry for the root file system (this used to be
3549 * done with no locks held).
3550 */
3551 vfs_list_lock();
3552 /*
3553 * Link into the vfs list proper.
3554 */
3555 if (vfsp == &root) {
3556 /*
3557 * Assert: This vfs is already on the list as its first entry.
3558 * Thus, there's nothing to do.
3559 */
3560 ASSERT(rootvfs == vfsp);
3561 /*
3562 * Add it to the head of the global zone's vfslist.
3563 */
3564 ASSERT(zone == global_zone);
3565 ASSERT(zone->zone_vfslist == NULL);
3566 zone->zone_vfslist = vfsp;
3567 } else {
3568 /*
3569 * Link to end of list using vfs_prev (as rootvfs is now a
3570 * doubly linked circular list) so list is in mount order for
3571 * mnttab use.
3572 */
3573 rootvfs->vfs_prev->vfs_next = vfsp;
3574 vfsp->vfs_prev = rootvfs->vfs_prev;
3575 rootvfs->vfs_prev = vfsp;
3576 vfsp->vfs_next = rootvfs;
3577
3578 /*
3579 * Do it again for the zone-private list (which may be NULL).
3580 */
3581 if (zone->zone_vfslist == NULL) {
3582 ASSERT(zone != global_zone);
3583 zone->zone_vfslist = vfsp;
3584 } else {
3585 zone->zone_vfslist->vfs_zone_prev->vfs_zone_next = vfsp;
3586 vfsp->vfs_zone_prev = zone->zone_vfslist->vfs_zone_prev;
3587 zone->zone_vfslist->vfs_zone_prev = vfsp;
3588 vfsp->vfs_zone_next = zone->zone_vfslist;
3589 }
3590 }
3591
3592 /*
3593 * Link into the hash table, inserting it at the end, so that LOFS
3594 * with the same fsid as UFS (or other) file systems will not hide
3595 * the UFS.
3596 */
3597 vfs_hash_add(vfsp, 0);
3598
3599 /*
3600 * update the mnttab modification time
3601 */
3602 vfs_mnttab_modtimeupd();
3603 vfs_list_unlock();
3604 zone_rele(zone);
3605 }
3606
3607 void
3608 vfs_list_remove(struct vfs *vfsp)
3609 {
3610 zone_t *zone;
3611
3612 zone = zone_find_by_path(refstr_value(vfsp->vfs_mntpt));
3613 ASSERT(zone != NULL);
3614 /*
3615 * Callers are responsible for preventing attempts to unmount the
3616 * root.
3617 */
3618 ASSERT(vfsp != rootvfs);
3619
3620 vfs_list_lock();
3621
3622 /*
3623 * Remove from hash.
3624 */
3625 vfs_hash_remove(vfsp);
3626
3627 /*
3628 * Remove from vfs list.
3629 */
3630 vfsp->vfs_prev->vfs_next = vfsp->vfs_next;
3631 vfsp->vfs_next->vfs_prev = vfsp->vfs_prev;
3632 vfsp->vfs_next = vfsp->vfs_prev = NULL;
3633
3634 /*
3635 * Remove from zone-specific vfs list.
3636 */
3637 if (zone->zone_vfslist == vfsp)
3638 zone->zone_vfslist = vfsp->vfs_zone_next;
3639
3640 if (vfsp->vfs_zone_next == vfsp) {
3641 ASSERT(vfsp->vfs_zone_prev == vfsp);
3642 ASSERT(zone->zone_vfslist == vfsp);
3643 zone->zone_vfslist = NULL;
3644 }
3645
3646 vfsp->vfs_zone_prev->vfs_zone_next = vfsp->vfs_zone_next;
3647 vfsp->vfs_zone_next->vfs_zone_prev = vfsp->vfs_zone_prev;
3648 vfsp->vfs_zone_next = vfsp->vfs_zone_prev = NULL;
3649
3650 /*
3651 * update the mnttab modification time
3652 */
3653 vfs_mnttab_modtimeupd();
3654 vfs_list_unlock();
3655 zone_rele(zone);
3656 }
3657
3658 struct vfs *
3659 getvfs(fsid_t *fsid)
3660 {
3661 struct vfs *vfsp;
3662 int val0 = fsid->val[0];
3663 int val1 = fsid->val[1];
3664 dev_t dev = expldev(val0);
3665 int vhno = VFSHASH(getmajor(dev), getminor(dev));
3666 kmutex_t *hmp = &rvfs_list[vhno].rvfs_lock;
3667
3668 mutex_enter(hmp);
3669 for (vfsp = rvfs_list[vhno].rvfs_head; vfsp; vfsp = vfsp->vfs_hash) {
3670 if (vfsp->vfs_fsid.val[0] == val0 &&
3671 vfsp->vfs_fsid.val[1] == val1) {
3672 VFS_HOLD(vfsp);
3673 mutex_exit(hmp);
3674 return (vfsp);
3675 }
3676 }
3677 mutex_exit(hmp);
3678 return (NULL);
3679 }
3680
3681 /*
3682 * Search the vfs mount in progress list for a specified device/vfs entry.
3683 * Returns 0 if the first entry in the list that the device matches has the
3684 * given vfs pointer as well. If the device matches but a different vfs
3685 * pointer is encountered in the list before the given vfs pointer then
3686 * a 1 is returned.
3687 */
3688
3689 int
3690 vfs_devmounting(dev_t dev, struct vfs *vfsp)
3691 {
3692 int retval = 0;
3693 struct ipmnt *mipp;
3694
3695 mutex_enter(&vfs_miplist_mutex);
3696 for (mipp = vfs_miplist; mipp != NULL; mipp = mipp->mip_next) {
3697 if (mipp->mip_dev == dev) {
3698 if (mipp->mip_vfsp != vfsp)
3699 retval = 1;
3700 break;
3701 }
3702 }
3703 mutex_exit(&vfs_miplist_mutex);
3704 return (retval);
3705 }
3706
3707 /*
3708 * Search the vfs list for a specified device. Returns 1, if entry is found
3709 * or 0 if no suitable entry is found.
3710 */
3711
3712 int
3713 vfs_devismounted(dev_t dev)
3714 {
3715 struct vfs *vfsp;
3716 int found;
3717
3718 vfs_list_read_lock();
3719 vfsp = rootvfs;
3720 found = 0;
3721 do {
3722 if (vfsp->vfs_dev == dev) {
3723 found = 1;
3724 break;
3725 }
3726 vfsp = vfsp->vfs_next;
3727 } while (vfsp != rootvfs);
3728
3729 vfs_list_unlock();
3730 return (found);
3731 }
3732
3733 /*
3734 * Search the vfs list for a specified device. Returns a pointer to it
3735 * or NULL if no suitable entry is found. The caller of this routine
3736 * is responsible for releasing the returned vfs pointer.
3737 */
3738 struct vfs *
3739 vfs_dev2vfsp(dev_t dev)
3740 {
3741 struct vfs *vfsp;
3742 int found;
3743
3744 vfs_list_read_lock();
3745 vfsp = rootvfs;
3746 found = 0;
3747 do {
3748 /*
3749 * The following could be made more efficient by making
3750 * the entire loop use vfs_zone_next if the call is from
3751 * a zone. The only callers, however, ustat(2) and
3752 * umount2(2), don't seem to justify the added
3753 * complexity at present.
3754 */
3755 if (vfsp->vfs_dev == dev &&
3756 ZONE_PATH_VISIBLE(refstr_value(vfsp->vfs_mntpt),
3757 curproc->p_zone)) {
3758 VFS_HOLD(vfsp);
3759 found = 1;
3760 break;
3761 }
3762 vfsp = vfsp->vfs_next;
3763 } while (vfsp != rootvfs);
3764 vfs_list_unlock();
3765 return (found ? vfsp: NULL);
3766 }
3767
3768 /*
3769 * Search the vfs list for a specified mntpoint. Returns a pointer to it
3770 * or NULL if no suitable entry is found. The caller of this routine
3771 * is responsible for releasing the returned vfs pointer.
3772 *
3773 * Note that if multiple mntpoints match, the last one matching is
3774 * returned in an attempt to return the "top" mount when overlay
3775 * mounts are covering the same mount point. This is accomplished by starting
3776 * at the end of the list and working our way backwards, stopping at the first
3777 * matching mount.
3778 */
3779 struct vfs *
3780 vfs_mntpoint2vfsp(const char *mp)
3781 {
3782 struct vfs *vfsp;
3783 struct vfs *retvfsp = NULL;
3784 zone_t *zone = curproc->p_zone;
3785 struct vfs *list;
3786
3787 vfs_list_read_lock();
3788 if (getzoneid() == GLOBAL_ZONEID) {
3789 /*
3790 * The global zone may see filesystems in any zone.
3791 */
3792 vfsp = rootvfs->vfs_prev;
3793 do {
3794 if (strcmp(refstr_value(vfsp->vfs_mntpt), mp) == 0) {
3795 retvfsp = vfsp;
3796 break;
3797 }
3798 vfsp = vfsp->vfs_prev;
3799 } while (vfsp != rootvfs->vfs_prev);
3800 } else if ((list = zone->zone_vfslist) != NULL) {
3801 const char *mntpt;
3802
3803 vfsp = list->vfs_zone_prev;
3804 do {
3805 mntpt = refstr_value(vfsp->vfs_mntpt);
3806 mntpt = ZONE_PATH_TRANSLATE(mntpt, zone);
3807 if (strcmp(mntpt, mp) == 0) {
3808 retvfsp = vfsp;
3809 break;
3810 }
3811 vfsp = vfsp->vfs_zone_prev;
3812 } while (vfsp != list->vfs_zone_prev);
3813 }
3814 if (retvfsp)
3815 VFS_HOLD(retvfsp);
3816 vfs_list_unlock();
3817 return (retvfsp);
3818 }
3819
3820 /*
3821 * Search the vfs list for a specified vfsops.
3822 * if vfs entry is found then return 1, else 0.
3823 */
3824 int
3825 vfs_opsinuse(vfsops_t *ops)
3826 {
3827 struct vfs *vfsp;
3828 int found;
3829
3830 vfs_list_read_lock();
3831 vfsp = rootvfs;
3832 found = 0;
3833 do {
3834 if (vfs_getops(vfsp) == ops) {
3835 found = 1;
3836 break;
3837 }
3838 vfsp = vfsp->vfs_next;
3839 } while (vfsp != rootvfs);
3840 vfs_list_unlock();
3841 return (found);
3842 }
3843
3844 /*
3845 * Allocate an entry in vfssw for a file system type
3846 */
3847 struct vfssw *
3848 allocate_vfssw(const char *type)
3849 {
3850 struct vfssw *vswp;
3851
3852 if (type[0] == '\0' || strlen(type) + 1 > _ST_FSTYPSZ) {
3853 /*
3854 * The vfssw table uses the empty string to identify an
3855 * available entry; we cannot add any type which has
3856 * a leading NUL. The string length is limited to
3857 * the size of the st_fstype array in struct stat.
3858 */
3859 return (NULL);
3860 }
3861
3862 ASSERT(VFSSW_WRITE_LOCKED());
3863 for (vswp = &vfssw[1]; vswp < &vfssw[nfstype]; vswp++)
3864 if (!ALLOCATED_VFSSW(vswp)) {
3865 vswp->vsw_name = kmem_alloc(strlen(type) + 1, KM_SLEEP);
3866 (void) strcpy(vswp->vsw_name, type);
3867 ASSERT(vswp->vsw_count == 0);
3868 vswp->vsw_count = 1;
3869 mutex_init(&vswp->vsw_lock, NULL, MUTEX_DEFAULT, NULL);
3870 return (vswp);
3871 }
3872 return (NULL);
3873 }
3874
3875 /*
3876 * Impose additional layer of translation between vfstype names
3877 * and module names in the filesystem.
3878 */
3879 static const char *
3880 vfs_to_modname(const char *vfstype)
3881 {
3882 if (strcmp(vfstype, "proc") == 0) {
3883 vfstype = "procfs";
3884 } else if (strcmp(vfstype, "fd") == 0) {
3885 vfstype = "fdfs";
3886 } else if (strncmp(vfstype, "nfs", 3) == 0) {
3887 vfstype = "nfs";
3888 }
3889
3890 return (vfstype);
3891 }
3892
3893 /*
3894 * Find a vfssw entry given a file system type name.
3895 * Try to autoload the filesystem if it's not found.
3896 * If it's installed, return the vfssw locked to prevent unloading.
3897 */
3898 struct vfssw *
3899 vfs_getvfssw(const char *type)
3900 {
3901 struct vfssw *vswp;
3902 const char *modname;
3903
3904 RLOCK_VFSSW();
3905 vswp = vfs_getvfsswbyname(type);
3906 modname = vfs_to_modname(type);
3907
3908 if (rootdir == NULL) {
3909 /*
3910 * If we haven't yet loaded the root file system, then our
3911 * _init won't be called until later. Allocate vfssw entry,
3912 * because mod_installfs won't be called.
3913 */
3914 if (vswp == NULL) {
3915 RUNLOCK_VFSSW();
3916 WLOCK_VFSSW();
3917 if ((vswp = vfs_getvfsswbyname(type)) == NULL) {
3918 if ((vswp = allocate_vfssw(type)) == NULL) {
3919 WUNLOCK_VFSSW();
3920 return (NULL);
3921 }
3922 }
3923 WUNLOCK_VFSSW();
3924 RLOCK_VFSSW();
3925 }
3926 if (!VFS_INSTALLED(vswp)) {
3927 RUNLOCK_VFSSW();
3928 (void) modloadonly("fs", modname);
3929 } else
3930 RUNLOCK_VFSSW();
3931 return (vswp);
3932 }
3933
3934 /*
3935 * Try to load the filesystem. Before calling modload(), we drop
3936 * our lock on the VFS switch table, and pick it up after the
3937 * module is loaded. However, there is a potential race: the
3938 * module could be unloaded after the call to modload() completes
3939 * but before we pick up the lock and drive on. Therefore,
3940 * we keep reloading the module until we've loaded the module
3941 * _and_ we have the lock on the VFS switch table.
3942 */
3943 while (vswp == NULL || !VFS_INSTALLED(vswp)) {
3944 RUNLOCK_VFSSW();
3945 if (modload("fs", modname) == -1)
3946 return (NULL);
3947 RLOCK_VFSSW();
3948 if (vswp == NULL)
3949 if ((vswp = vfs_getvfsswbyname(type)) == NULL)
3950 break;
3951 }
3952 RUNLOCK_VFSSW();
3953
3954 return (vswp);
3955 }
3956
3957 /*
3958 * Find a vfssw entry given a file system type name.
3959 */
3960 struct vfssw *
3961 vfs_getvfsswbyname(const char *type)
3962 {
3963 struct vfssw *vswp;
3964
3965 ASSERT(VFSSW_LOCKED());
3966 if (type == NULL || *type == '\0')
3967 return (NULL);
3968
3969 for (vswp = &vfssw[1]; vswp < &vfssw[nfstype]; vswp++) {
3970 if (strcmp(type, vswp->vsw_name) == 0) {
3971 vfs_refvfssw(vswp);
3972 return (vswp);
3973 }
3974 }
3975
3976 return (NULL);
3977 }
3978
3979 /*
3980 * Find a vfssw entry given a set of vfsops.
3981 */
3982 struct vfssw *
3983 vfs_getvfsswbyvfsops(vfsops_t *vfsops)
3984 {
3985 struct vfssw *vswp;
3986
3987 RLOCK_VFSSW();
3988 for (vswp = &vfssw[1]; vswp < &vfssw[nfstype]; vswp++) {
3989 if (ALLOCATED_VFSSW(vswp) && &vswp->vsw_vfsops == vfsops) {
3990 vfs_refvfssw(vswp);
3991 RUNLOCK_VFSSW();
3992 return (vswp);
3993 }
3994 }
3995 RUNLOCK_VFSSW();
3996
3997 return (NULL);
3998 }
3999
4000 /*
4001 * Reference a vfssw entry.
4002 */
4003 void
4004 vfs_refvfssw(struct vfssw *vswp)
4005 {
4006
4007 mutex_enter(&vswp->vsw_lock);
4008 vswp->vsw_count++;
4009 mutex_exit(&vswp->vsw_lock);
4010 }
4011
4012 /*
4013 * Unreference a vfssw entry.
4014 */
4015 void
4016 vfs_unrefvfssw(struct vfssw *vswp)
4017 {
4018
4019 mutex_enter(&vswp->vsw_lock);
4020 vswp->vsw_count--;
4021 mutex_exit(&vswp->vsw_lock);
4022 }
4023
4024 static int sync_retries = 20; /* number of retries when not making progress */
4025 static int sync_triesleft; /* portion of sync_retries remaining */
4026
4027 static pgcnt_t old_pgcnt, new_pgcnt;
4028 static int new_bufcnt, old_bufcnt;
4029
4030 /*
4031 * Sync all of the mounted filesystems, and then wait for the actual i/o to
4032 * complete. We wait by counting the number of dirty pages and buffers,
4033 * pushing them out using bio_busy() and page_busy(), and then counting again.
4034 * This routine is used during the uadmin A_SHUTDOWN code. It should only
4035 * be used after some higher-level mechanism has quiesced the system so that
4036 * new writes are not being initiated while we are waiting for completion.
4037 *
4038 * To ensure finite running time, our algorithm uses sync_triesleft (a progress
4039 * counter used by the vfs_syncall() loop below). It is declared above so
4040 * it can be found easily in the debugger.
4041 *
4042 * The sync_triesleft counter is updated by vfs_syncall() itself. If we make
4043 * sync_retries consecutive calls to bio_busy() and page_busy() without
4044 * decreasing either the number of dirty buffers or dirty pages below the
4045 * lowest count we have seen so far, we give up and return from vfs_syncall().
4046 *
4047 * Each loop iteration ends with a call to delay() one second to allow time for
4048 * i/o completion and to permit the user time to read our progress messages.
4049 */
4050 void
4051 vfs_syncall(void)
4052 {
4053 if (rootdir == NULL && !modrootloaded)
4054 return; /* no filesystems have been loaded yet */
4055
4056 printf("syncing file systems...");
4057 sync();
4058
4059 sync_triesleft = sync_retries;
4060
4061 old_bufcnt = new_bufcnt = INT_MAX;
4062 old_pgcnt = new_pgcnt = ULONG_MAX;
4063
4064 while (sync_triesleft > 0) {
4065 old_bufcnt = MIN(old_bufcnt, new_bufcnt);
4066 old_pgcnt = MIN(old_pgcnt, new_pgcnt);
4067
4068 new_bufcnt = bio_busy(B_TRUE);
4069 new_pgcnt = page_busy(B_TRUE);
4070
4071 if (new_bufcnt == 0 && new_pgcnt == 0)
4072 break;
4073
4074 if (new_bufcnt < old_bufcnt || new_pgcnt < old_pgcnt)
4075 sync_triesleft = sync_retries;
4076 else
4077 sync_triesleft--;
4078
4079 if (new_bufcnt)
4080 printf(" [%d]", new_bufcnt);
4081 if (new_pgcnt)
4082 printf(" %lu", new_pgcnt);
4083
4084 delay(hz);
4085 }
4086
4087 if (new_bufcnt != 0 || new_pgcnt != 0)
4088 printf(" done (not all i/o completed)\n");
4089 else
4090 printf(" done\n");
4091
4092 delay(hz);
4093 }
4094
4095 /*
4096 * Map VFS flags to statvfs flags. These shouldn't really be separate
4097 * flags at all.
4098 */
4099 uint_t
4100 vf_to_stf(uint_t vf)
4101 {
4102 uint_t stf = 0;
4103
4104 if (vf & VFS_RDONLY)
4105 stf |= ST_RDONLY;
4106 if (vf & VFS_NOSETUID)
4107 stf |= ST_NOSUID;
4108 if (vf & VFS_NOTRUNC)
4109 stf |= ST_NOTRUNC;
4110
4111 return (stf);
4112 }
4113
4114 /*
4115 * Entries for (illegal) fstype 0.
4116 */
4117 /* ARGSUSED */
4118 int
4119 vfsstray_sync(struct vfs *vfsp, short arg, struct cred *cr)
4120 {
4121 cmn_err(CE_PANIC, "stray vfs operation");
4122 return (0);
4123 }
4124
4125 /*
4126 * Entries for (illegal) fstype 0.
4127 */
4128 int
4129 vfsstray(void)
4130 {
4131 cmn_err(CE_PANIC, "stray vfs operation");
4132 return (0);
4133 }
4134
4135 /*
4136 * Support for dealing with forced UFS unmount and its interaction with
4137 * LOFS. Could be used by any filesystem.
4138 * See bug 1203132.
4139 */
4140 int
4141 vfs_EIO(void)
4142 {
4143 return (EIO);
4144 }
4145
4146 /*
4147 * We've gotta define the op for sync separately, since the compiler gets
4148 * confused if we mix and match ANSI and normal style prototypes when
4149 * a "short" argument is present and spits out a warning.
4150 */
4151 /*ARGSUSED*/
4152 int
4153 vfs_EIO_sync(struct vfs *vfsp, short arg, struct cred *cr)
4154 {
4155 return (EIO);
4156 }
4157
4158 vfs_t EIO_vfs;
4159 vfsops_t *EIO_vfsops;
4160
4161 /*
4162 * Called from startup() to initialize all loaded vfs's
4163 */
4164 void
4165 vfsinit(void)
4166 {
4167 struct vfssw *vswp;
4168 int error;
4169 extern int vopstats_enabled;
4170 extern void vopstats_startup();
4171
4172 static const fs_operation_def_t EIO_vfsops_template[] = {
4173 VFSNAME_MOUNT, { .error = vfs_EIO },
4174 VFSNAME_UNMOUNT, { .error = vfs_EIO },
4175 VFSNAME_ROOT, { .error = vfs_EIO },
4176 VFSNAME_STATVFS, { .error = vfs_EIO },
4177 VFSNAME_SYNC, { .vfs_sync = vfs_EIO_sync },
4178 VFSNAME_VGET, { .error = vfs_EIO },
4179 VFSNAME_MOUNTROOT, { .error = vfs_EIO },
4180 VFSNAME_FREEVFS, { .error = vfs_EIO },
4181 VFSNAME_VNSTATE, { .error = vfs_EIO },
4182 NULL, NULL
4183 };
4184
4185 static const fs_operation_def_t stray_vfsops_template[] = {
4186 VFSNAME_MOUNT, { .error = vfsstray },
4187 VFSNAME_UNMOUNT, { .error = vfsstray },
4188 VFSNAME_ROOT, { .error = vfsstray },
4189 VFSNAME_STATVFS, { .error = vfsstray },
4190 VFSNAME_SYNC, { .vfs_sync = vfsstray_sync },
4191 VFSNAME_VGET, { .error = vfsstray },
4192 VFSNAME_MOUNTROOT, { .error = vfsstray },
4193 VFSNAME_FREEVFS, { .error = vfsstray },
4194 VFSNAME_VNSTATE, { .error = vfsstray },
4195 NULL, NULL
4196 };
4197
4198 /* Create vfs cache */
4199 vfs_cache = kmem_cache_create("vfs_cache", sizeof (struct vfs),
4200 sizeof (uintptr_t), NULL, NULL, NULL, NULL, NULL, 0);
4201
4202 /* Initialize the vnode cache (file systems may use it during init). */
4203 vn_create_cache();
4204
4205 /* Setup event monitor framework */
4206 fem_init();
4207
4208 /* Initialize the dummy stray file system type. */
4209 error = vfs_setfsops(0, stray_vfsops_template, NULL);
4210
4211 /* Initialize the dummy EIO file system. */
4212 error = vfs_makefsops(EIO_vfsops_template, &EIO_vfsops);
4213 if (error != 0) {
4214 cmn_err(CE_WARN, "vfsinit: bad EIO vfs ops template");
4215 /* Shouldn't happen, but not bad enough to panic */
4216 }
4217
4218 VFS_INIT(&EIO_vfs, EIO_vfsops, (caddr_t)NULL);
4219
4220 /*
4221 * Default EIO_vfs.vfs_flag to VFS_UNMOUNTED so a lookup
4222 * on this vfs can immediately notice it's invalid.
4223 */
4224 EIO_vfs.vfs_flag |= VFS_UNMOUNTED;
4225
4226 /*
4227 * Call the init routines of non-loadable filesystems only.
4228 * Filesystems which are loaded as separate modules will be
4229 * initialized by the module loading code instead.
4230 */
4231
4232 for (vswp = &vfssw[1]; vswp < &vfssw[nfstype]; vswp++) {
4233 RLOCK_VFSSW();
4234 if (vswp->vsw_init != NULL)
4235 (*vswp->vsw_init)(vswp - vfssw, vswp->vsw_name);
4236 RUNLOCK_VFSSW();
4237 }
4238
4239 vopstats_startup();
4240
4241 if (vopstats_enabled) {
4242 /* EIO_vfs can collect stats, but we don't retrieve them */
4243 initialize_vopstats(&EIO_vfs.vfs_vopstats);
4244 EIO_vfs.vfs_fstypevsp = NULL;
4245 EIO_vfs.vfs_vskap = NULL;
4246 EIO_vfs.vfs_flag |= VFS_STATS;
4247 }
4248
4249 xattr_init();
4250
4251 reparse_point_init();
4252 }
4253
4254 vfs_t *
4255 vfs_alloc(int kmflag)
4256 {
4257 vfs_t *vfsp;
4258
4259 vfsp = kmem_cache_alloc(vfs_cache, kmflag);
4260
4261 /*
4262 * Do the simplest initialization here.
4263 * Everything else gets done in vfs_init()
4264 */
4265 bzero(vfsp, sizeof (vfs_t));
4266 return (vfsp);
4267 }
4268
4269 void
4270 vfs_free(vfs_t *vfsp)
4271 {
4272 /*
4273 * One would be tempted to assert that "vfsp->vfs_count == 0".
4274 * The problem is that this gets called out of domount() with
4275 * a partially initialized vfs and a vfs_count of 1. This is
4276 * also called from vfs_rele() with a vfs_count of 0. We can't
4277 * call VFS_RELE() from domount() if VFS_MOUNT() hasn't successfully
4278 * returned. This is because VFS_MOUNT() fully initializes the
4279 * vfs structure and its associated data. VFS_RELE() will call
4280 * VFS_FREEVFS() which may panic the system if the data structures
4281 * aren't fully initialized from a successful VFS_MOUNT()).
4282 */
4283
4284 /* If FEM was in use, make sure everything gets cleaned up */
4285 if (vfsp->vfs_femhead) {
4286 ASSERT(vfsp->vfs_femhead->femh_list == NULL);
4287 mutex_destroy(&vfsp->vfs_femhead->femh_lock);
4288 kmem_free(vfsp->vfs_femhead, sizeof (*(vfsp->vfs_femhead)));
4289 vfsp->vfs_femhead = NULL;
4290 }
4291
4292 if (vfsp->vfs_implp)
4293 vfsimpl_teardown(vfsp);
4294 sema_destroy(&vfsp->vfs_reflock);
4295 kmem_cache_free(vfs_cache, vfsp);
4296 }
4297
4298 /*
4299 * Increments the vfs reference count by one atomically.
4300 */
4301 void
4302 vfs_hold(vfs_t *vfsp)
4303 {
4304 atomic_inc_32(&vfsp->vfs_count);
4305 ASSERT(vfsp->vfs_count != 0);
4306 }
4307
4308 /*
4309 * Decrements the vfs reference count by one atomically. When
4310 * vfs reference count becomes zero, it calls the file system
4311 * specific vfs_freevfs() to free up the resources.
4312 */
4313 void
4314 vfs_rele(vfs_t *vfsp)
4315 {
4316 ASSERT(vfsp->vfs_count != 0);
4317 if (atomic_dec_32_nv(&vfsp->vfs_count) == 0) {
4318 VFS_FREEVFS(vfsp);
4319 lofi_remove(vfsp);
4320 if (vfsp->vfs_zone)
4321 zone_rele_ref(&vfsp->vfs_implp->vi_zone_ref,
4322 ZONE_REF_VFS);
4323 vfs_freemnttab(vfsp);
4324 vfs_free(vfsp);
4325 }
4326 }
4327
4328 /*
4329 * Generic operations vector support.
4330 *
4331 * This is used to build operations vectors for both the vfs and vnode.
4332 * It's normally called only when a file system is loaded.
4333 *
4334 * There are many possible algorithms for this, including the following:
4335 *
4336 * (1) scan the list of known operations; for each, see if the file system
4337 * includes an entry for it, and fill it in as appropriate.
4338 *
4339 * (2) set up defaults for all known operations. scan the list of ops
4340 * supplied by the file system; for each which is both supplied and
4341 * known, fill it in.
4342 *
4343 * (3) sort the lists of known ops & supplied ops; scan the list, filling
4344 * in entries as we go.
4345 *
4346 * we choose (1) for simplicity, and because performance isn't critical here.
4347 * note that (2) could be sped up using a precomputed hash table on known ops.
4348 * (3) could be faster than either, but only if the lists were very large or
4349 * supplied in sorted order.
4350 *
4351 */
4352
4353 int
4354 fs_build_vector(void *vector, int *unused_ops,
4355 const fs_operation_trans_def_t *translation,
4356 const fs_operation_def_t *operations)
4357 {
4358 int i, num_trans, num_ops, used;
4359
4360 /*
4361 * Count the number of translations and the number of supplied
4362 * operations.
4363 */
4364
4365 {
4366 const fs_operation_trans_def_t *p;
4367
4368 for (num_trans = 0, p = translation;
4369 p->name != NULL;
4370 num_trans++, p++)
4371 ;
4372 }
4373
4374 {
4375 const fs_operation_def_t *p;
4376
4377 for (num_ops = 0, p = operations;
4378 p->name != NULL;
4379 num_ops++, p++)
4380 ;
4381 }
4382
4383 /* Walk through each operation known to our caller. There will be */
4384 /* one entry in the supplied "translation table" for each. */
4385
4386 used = 0;
4387
4388 for (i = 0; i < num_trans; i++) {
4389 int j, found;
4390 char *curname;
4391 fs_generic_func_p result;
4392 fs_generic_func_p *location;
4393
4394 curname = translation[i].name;
4395
4396 /* Look for a matching operation in the list supplied by the */
4397 /* file system. */
4398
4399 found = 0;
4400
4401 for (j = 0; j < num_ops; j++) {
4402 if (strcmp(operations[j].name, curname) == 0) {
4403 used++;
4404 found = 1;
4405 break;
4406 }
4407 }
4408
4409 /*
4410 * If the file system is using a "placeholder" for default
4411 * or error functions, grab the appropriate function out of
4412 * the translation table. If the file system didn't supply
4413 * this operation at all, use the default function.
4414 */
4415
4416 if (found) {
4417 result = operations[j].func.fs_generic;
4418 if (result == fs_default) {
4419 result = translation[i].defaultFunc;
4420 } else if (result == fs_error) {
4421 result = translation[i].errorFunc;
4422 } else if (result == NULL) {
4423 /* Null values are PROHIBITED */
4424 return (EINVAL);
4425 }
4426 } else {
4427 result = translation[i].defaultFunc;
4428 }
4429
4430 /* Now store the function into the operations vector. */
4431
4432 location = (fs_generic_func_p *)
4433 (((char *)vector) + translation[i].offset);
4434
4435 *location = result;
4436 }
4437
4438 *unused_ops = num_ops - used;
4439
4440 return (0);
4441 }
4442
4443 /* Placeholder functions, should never be called. */
4444
4445 int
4446 fs_error(void)
4447 {
4448 cmn_err(CE_PANIC, "fs_error called");
4449 return (0);
4450 }
4451
4452 int
4453 fs_default(void)
4454 {
4455 cmn_err(CE_PANIC, "fs_default called");
4456 return (0);
4457 }
4458
4459 #ifdef __sparc
4460
4461 /*
4462 * Part of the implementation of booting off a mirrored root
4463 * involves a change of dev_t for the root device. To
4464 * accomplish this, first remove the existing hash table
4465 * entry for the root device, convert to the new dev_t,
4466 * then re-insert in the hash table at the head of the list.
4467 */
4468 void
4469 vfs_root_redev(vfs_t *vfsp, dev_t ndev, int fstype)
4470 {
4471 vfs_list_lock();
4472
4473 vfs_hash_remove(vfsp);
4474
4475 vfsp->vfs_dev = ndev;
4476 vfs_make_fsid(&vfsp->vfs_fsid, ndev, fstype);
4477
4478 vfs_hash_add(vfsp, 1);
4479
4480 vfs_list_unlock();
4481 }
4482
4483 #else /* x86 NEWBOOT */
4484
4485 #if defined(__x86)
4486 extern int hvmboot_rootconf();
4487 #endif /* __x86 */
4488
4489 extern ib_boot_prop_t *iscsiboot_prop;
4490
4491 int
4492 rootconf()
4493 {
4494 int error;
4495 struct vfssw *vsw;
4496 extern void pm_init();
4497 char *fstyp, *fsmod;
4498 int ret = -1;
4499
4500 getrootfs(&fstyp, &fsmod);
4501
4502 #if defined(__x86)
4503 /*
4504 * hvmboot_rootconf() is defined in the hvm_bootstrap misc module,
4505 * which lives in /platform/i86hvm, and hence is only available when
4506 * booted in an x86 hvm environment. If the hvm_bootstrap misc module
4507 * is not available then the modstub for this function will return 0.
4508 * If the hvm_bootstrap misc module is available it will be loaded
4509 * and hvmboot_rootconf() will be invoked.
4510 */
4511 if (error = hvmboot_rootconf())
4512 return (error);
4513 #endif /* __x86 */
4514
4515 if (error = clboot_rootconf())
4516 return (error);
4517
4518 if (modload("fs", fsmod) == -1)
4519 panic("Cannot _init %s module", fsmod);
4520
4521 RLOCK_VFSSW();
4522 vsw = vfs_getvfsswbyname(fstyp);
4523 RUNLOCK_VFSSW();
4524 if (vsw == NULL) {
4525 cmn_err(CE_CONT, "Cannot find %s filesystem\n", fstyp);
4526 return (ENXIO);
4527 }
4528 VFS_INIT(rootvfs, &vsw->vsw_vfsops, 0);
4529 VFS_HOLD(rootvfs);
4530
4531 /* always mount readonly first */
4532 rootvfs->vfs_flag |= VFS_RDONLY;
4533
4534 pm_init();
4535
4536 if (netboot && iscsiboot_prop) {
4537 cmn_err(CE_WARN, "NFS boot and iSCSI boot"
4538 " shouldn't happen in the same time");
4539 return (EINVAL);
4540 }
4541
4542 if (netboot || iscsiboot_prop) {
4543 ret = strplumb();
4544 if (ret != 0) {
4545 cmn_err(CE_WARN, "Cannot plumb network device %d", ret);
4546 return (EFAULT);
4547 }
4548 }
4549
4550 if ((ret == 0) && iscsiboot_prop) {
4551 ret = modload("drv", "iscsi");
4552 /* -1 indicates fail */
4553 if (ret == -1) {
4554 cmn_err(CE_WARN, "Failed to load iscsi module");
4555 iscsi_boot_prop_free();
4556 return (EINVAL);
4557 } else {
4558 if (!i_ddi_attach_pseudo_node("iscsi")) {
4559 cmn_err(CE_WARN,
4560 "Failed to attach iscsi driver");
4561 iscsi_boot_prop_free();
4562 return (ENODEV);
4563 }
4564 }
4565 }
4566
4567 error = VFS_MOUNTROOT(rootvfs, ROOT_INIT);
4568 vfs_unrefvfssw(vsw);
4569 rootdev = rootvfs->vfs_dev;
4570
4571 if (error)
4572 cmn_err(CE_CONT, "Cannot mount root on %s fstype %s\n",
4573 rootfs.bo_name, fstyp);
4574 else
4575 cmn_err(CE_CONT, "?root on %s fstype %s\n",
4576 rootfs.bo_name, fstyp);
4577 return (error);
4578 }
4579
4580 /*
4581 * XXX this is called by nfs only and should probably be removed
4582 * If booted with ASKNAME, prompt on the console for a filesystem
4583 * name and return it.
4584 */
4585 void
4586 getfsname(char *askfor, char *name, size_t namelen)
4587 {
4588 if (boothowto & RB_ASKNAME) {
4589 printf("%s name: ", askfor);
4590 console_gets(name, namelen);
4591 }
4592 }
4593
4594 /*
4595 * Init the root filesystem type (rootfs.bo_fstype) from the "fstype"
4596 * property.
4597 *
4598 * Filesystem types starting with the prefix "nfs" are diskless clients;
4599 * init the root filename name (rootfs.bo_name), too.
4600 *
4601 * If we are booting via NFS we currently have these options:
4602 * nfs - dynamically choose NFS V2, V3, or V4 (default)
4603 * nfs2 - force NFS V2
4604 * nfs3 - force NFS V3
4605 * nfs4 - force NFS V4
4606 * Because we need to maintain backward compatibility with the naming
4607 * convention that the NFS V2 filesystem name is "nfs" (see vfs_conf.c)
4608 * we need to map "nfs" => "nfsdyn" and "nfs2" => "nfs". The dynamic
4609 * nfs module will map the type back to either "nfs", "nfs3", or "nfs4".
4610 * This is only for root filesystems, all other uses will expect
4611 * that "nfs" == NFS V2.
4612 */
4613 static void
4614 getrootfs(char **fstypp, char **fsmodp)
4615 {
4616 char *propstr = NULL;
4617
4618 /*
4619 * Check fstype property; for diskless it should be one of "nfs",
4620 * "nfs2", "nfs3" or "nfs4".
4621 */
4622 if (ddi_prop_lookup_string(DDI_DEV_T_ANY, ddi_root_node(),
4623 DDI_PROP_DONTPASS, "fstype", &propstr)
4624 == DDI_SUCCESS) {
4625 (void) strncpy(rootfs.bo_fstype, propstr, BO_MAXFSNAME);
4626 ddi_prop_free(propstr);
4627
4628 /*
4629 * if the boot property 'fstype' is not set, but 'zfs-bootfs' is set,
4630 * assume the type of this root filesystem is 'zfs'.
4631 */
4632 } else if (ddi_prop_lookup_string(DDI_DEV_T_ANY, ddi_root_node(),
4633 DDI_PROP_DONTPASS, "zfs-bootfs", &propstr)
4634 == DDI_SUCCESS) {
4635 (void) strncpy(rootfs.bo_fstype, "zfs", BO_MAXFSNAME);
4636 ddi_prop_free(propstr);
4637 }
4638
4639 if (strncmp(rootfs.bo_fstype, "nfs", 3) != 0) {
4640 *fstypp = *fsmodp = rootfs.bo_fstype;
4641 return;
4642 }
4643
4644 ++netboot;
4645
4646 if (strcmp(rootfs.bo_fstype, "nfs2") == 0)
4647 (void) strcpy(rootfs.bo_fstype, "nfs");
4648 else if (strcmp(rootfs.bo_fstype, "nfs") == 0)
4649 (void) strcpy(rootfs.bo_fstype, "nfsdyn");
4650
4651 /*
4652 * check if path to network interface is specified in bootpath
4653 * or by a hypervisor domain configuration file.
4654 * XXPV - enable strlumb_get_netdev_path()
4655 */
4656 if (ddi_prop_exists(DDI_DEV_T_ANY, ddi_root_node(), DDI_PROP_DONTPASS,
4657 "xpv-nfsroot")) {
4658 (void) strcpy(rootfs.bo_name, "/xpvd/xnf@0");
4659 } else if (ddi_prop_lookup_string(DDI_DEV_T_ANY, ddi_root_node(),
4660 DDI_PROP_DONTPASS, "bootpath", &propstr)
4661 == DDI_SUCCESS) {
4662 (void) strncpy(rootfs.bo_name, propstr, BO_MAXOBJNAME);
4663 ddi_prop_free(propstr);
4664 } else {
4665 rootfs.bo_name[0] = '\0';
4666 }
4667 *fstypp = rootfs.bo_fstype;
4668 *fsmodp = "nfs";
4669 }
4670 #endif
4671
4672 /*
4673 * VFS feature routines
4674 */
4675
4676 #define VFTINDEX(feature) (((feature) >> 32) & 0xFFFFFFFF)
4677 #define VFTBITS(feature) ((feature) & 0xFFFFFFFFLL)
4678
4679 /* Register a feature in the vfs */
4680 void
4681 vfs_set_feature(vfs_t *vfsp, vfs_feature_t feature)
4682 {
4683 /* Note that vfs_featureset[] is found in *vfsp->vfs_implp */
4684 if (vfsp->vfs_implp == NULL)
4685 return;
4686
4687 vfsp->vfs_featureset[VFTINDEX(feature)] |= VFTBITS(feature);
4688 }
4689
4690 void
4691 vfs_clear_feature(vfs_t *vfsp, vfs_feature_t feature)
4692 {
4693 /* Note that vfs_featureset[] is found in *vfsp->vfs_implp */
4694 if (vfsp->vfs_implp == NULL)
4695 return;
4696 vfsp->vfs_featureset[VFTINDEX(feature)] &= VFTBITS(~feature);
4697 }
4698
4699 /*
4700 * Query a vfs for a feature.
4701 * Returns 1 if feature is present, 0 if not
4702 */
4703 int
4704 vfs_has_feature(vfs_t *vfsp, vfs_feature_t feature)
4705 {
4706 int ret = 0;
4707
4708 /* Note that vfs_featureset[] is found in *vfsp->vfs_implp */
4709 if (vfsp->vfs_implp == NULL)
4710 return (ret);
4711
4712 if (vfsp->vfs_featureset[VFTINDEX(feature)] & VFTBITS(feature))
4713 ret = 1;
4714
4715 return (ret);
4716 }
4717
4718 /*
4719 * Propagate feature set from one vfs to another
4720 */
4721 void
4722 vfs_propagate_features(vfs_t *from, vfs_t *to)
4723 {
4724 int i;
4725
4726 if (to->vfs_implp == NULL || from->vfs_implp == NULL)
4727 return;
4728
4729 for (i = 1; i <= to->vfs_featureset[0]; i++) {
4730 to->vfs_featureset[i] = from->vfs_featureset[i];
4731 }
4732 }
4733
4734 #define LOFINODE_PATH "/dev/lofi/%d"
4735
4736 /*
4737 * Return the vnode for the lofi node if there's a lofi mount in place.
4738 * Returns -1 when there's no lofi node, 0 on success, and > 0 on
4739 * failure.
4740 */
4741 int
4742 vfs_get_lofi(vfs_t *vfsp, vnode_t **vpp)
4743 {
4744 char *path = NULL;
4745 int strsize;
4746 int err;
4747
4748 if (vfsp->vfs_lofi_id == 0) {
4749 *vpp = NULL;
4750 return (-1);
4751 }
4752
4753 strsize = snprintf(NULL, 0, LOFINODE_PATH, vfsp->vfs_lofi_id);
4754 path = kmem_alloc(strsize + 1, KM_SLEEP);
4755 (void) snprintf(path, strsize + 1, LOFINODE_PATH, vfsp->vfs_lofi_id);
4756
4757 /*
4758 * We may be inside a zone, so we need to use the /dev path, but
4759 * it's created asynchronously, so we wait here.
4760 */
4761 for (;;) {
4762 err = lookupname(path, UIO_SYSSPACE, FOLLOW, NULLVPP, vpp);
4763
4764 if (err != ENOENT)
4765 break;
4766
4767 if ((err = delay_sig(hz / 8)) == EINTR)
4768 break;
4769 }
4770
4771 if (err)
4772 *vpp = NULL;
4773
4774 kmem_free(path, strsize + 1);
4775 return (err);
4776 }