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 * Copyright (c) 1988, 2010, Oracle and/or its affiliates. All rights reserved.
23 */
24
25 /* Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */
26 /* All Rights Reserved */
27
28 /*
29 * University Copyright- Copyright (c) 1982, 1986, 1988
30 * The Regents of the University of California
31 * All Rights Reserved
32 *
33 * University Acknowledgment- Portions of this document are derived from
34 * software developed by the University of California, Berkeley, and its
35 * contributors.
36 */
37
38 #include <sys/types.h>
39 #include <sys/t_lock.h>
40 #include <sys/param.h>
41 #include <sys/errno.h>
42 #include <sys/user.h>
43 #include <sys/fstyp.h>
44 #include <sys/kmem.h>
45 #include <sys/systm.h>
46 #include <sys/proc.h>
47 #include <sys/mount.h>
48 #include <sys/vfs.h>
49 #include <sys/vfs_opreg.h>
50 #include <sys/fem.h>
51 #include <sys/mntent.h>
52 #include <sys/stat.h>
53 #include <sys/statvfs.h>
54 #include <sys/statfs.h>
55 #include <sys/cred.h>
56 #include <sys/vnode.h>
57 #include <sys/rwstlock.h>
58 #include <sys/dnlc.h>
59 #include <sys/file.h>
60 #include <sys/time.h>
61 #include <sys/atomic.h>
62 #include <sys/cmn_err.h>
63 #include <sys/buf.h>
64 #include <sys/swap.h>
65 #include <sys/debug.h>
66 #include <sys/vnode.h>
67 #include <sys/modctl.h>
68 #include <sys/ddi.h>
69 #include <sys/pathname.h>
70 #include <sys/bootconf.h>
71 #include <sys/dumphdr.h>
72 #include <sys/dc_ki.h>
73 #include <sys/poll.h>
74 #include <sys/sunddi.h>
75 #include <sys/sysmacros.h>
76 #include <sys/zone.h>
77 #include <sys/policy.h>
78 #include <sys/ctfs.h>
79 #include <sys/objfs.h>
80 #include <sys/console.h>
81 #include <sys/reboot.h>
82 #include <sys/attr.h>
83 #include <sys/zio.h>
84 #include <sys/spa.h>
85 #include <sys/lofi.h>
86 #include <sys/bootprops.h>
87 #include <sys/fsh.h>
88 #include <sys/fsh_impl.h>
89
90 #include <vm/page.h>
91
92 #include <fs/fs_subr.h>
93 /* Private interfaces to create vopstats-related data structures */
94 extern void initialize_vopstats(vopstats_t *);
95 extern vopstats_t *get_fstype_vopstats(struct vfs *, struct vfssw *);
96 extern vsk_anchor_t *get_vskstat_anchor(struct vfs *);
97
98 static void vfs_clearmntopt_nolock(mntopts_t *, const char *, int);
99 static void vfs_setmntopt_nolock(mntopts_t *, const char *,
100 const char *, int, int);
101 static int vfs_optionisset_nolock(const mntopts_t *, const char *, char **);
102 static void vfs_freemnttab(struct vfs *);
103 static void vfs_freeopt(mntopt_t *);
104 static void vfs_swapopttbl_nolock(mntopts_t *, mntopts_t *);
105 static void vfs_swapopttbl(mntopts_t *, mntopts_t *);
106 static void vfs_copyopttbl_extend(const mntopts_t *, mntopts_t *, int);
107 static void vfs_createopttbl_extend(mntopts_t *, const char *,
108 const mntopts_t *);
109 static char **vfs_copycancelopt_extend(char **const, int);
110 static void vfs_freecancelopt(char **);
111 static void getrootfs(char **, char **);
112 static int getmacpath(dev_info_t *, void *);
113 static void vfs_mnttabvp_setup(void);
114
115 struct ipmnt {
116 struct ipmnt *mip_next;
117 dev_t mip_dev;
118 struct vfs *mip_vfsp;
119 };
120
121 static kmutex_t vfs_miplist_mutex;
122 static struct ipmnt *vfs_miplist = NULL;
123 static struct ipmnt *vfs_miplist_end = NULL;
124
125 static kmem_cache_t *vfs_cache; /* Pointer to VFS kmem cache */
126
127 /*
128 * VFS global data.
129 */
130 vnode_t *rootdir; /* pointer to root inode vnode. */
131 vnode_t *devicesdir; /* pointer to inode of devices root */
132 vnode_t *devdir; /* pointer to inode of dev root */
133
134 char *server_rootpath; /* root path for diskless clients */
135 char *server_hostname; /* hostname of diskless server */
136
137 static struct vfs root;
138 static struct vfs devices;
139 static struct vfs dev;
140 struct vfs *rootvfs = &root; /* pointer to root vfs; head of VFS list. */
141 rvfs_t *rvfs_list; /* array of vfs ptrs for vfs hash list */
142 int vfshsz = 512; /* # of heads/locks in vfs hash arrays */
143 /* must be power of 2! */
144 timespec_t vfs_mnttab_ctime; /* mnttab created time */
145 timespec_t vfs_mnttab_mtime; /* mnttab last modified time */
146 char *vfs_dummyfstype = "\0";
147 struct pollhead vfs_pollhd; /* for mnttab pollers */
148 struct vnode *vfs_mntdummyvp; /* to fake mnttab read/write for file events */
149 int mntfstype; /* will be set once mnt fs is mounted */
150
151 /*
152 * Table for generic options recognized in the VFS layer and acted
153 * on at this level before parsing file system specific options.
154 * The nosuid option is stronger than any of the devices and setuid
155 * options, so those are canceled when nosuid is seen.
156 *
157 * All options which are added here need to be added to the
158 * list of standard options in usr/src/cmd/fs.d/fslib.c as well.
159 */
160 /*
161 * VFS Mount options table
162 */
163 static char *ro_cancel[] = { MNTOPT_RW, NULL };
164 static char *rw_cancel[] = { MNTOPT_RO, NULL };
165 static char *suid_cancel[] = { MNTOPT_NOSUID, NULL };
166 static char *nosuid_cancel[] = { MNTOPT_SUID, MNTOPT_DEVICES, MNTOPT_NODEVICES,
167 MNTOPT_NOSETUID, MNTOPT_SETUID, NULL };
168 static char *devices_cancel[] = { MNTOPT_NODEVICES, NULL };
169 static char *nodevices_cancel[] = { MNTOPT_DEVICES, NULL };
170 static char *setuid_cancel[] = { MNTOPT_NOSETUID, NULL };
171 static char *nosetuid_cancel[] = { MNTOPT_SETUID, NULL };
172 static char *nbmand_cancel[] = { MNTOPT_NONBMAND, NULL };
173 static char *nonbmand_cancel[] = { MNTOPT_NBMAND, NULL };
174 static char *exec_cancel[] = { MNTOPT_NOEXEC, NULL };
175 static char *noexec_cancel[] = { MNTOPT_EXEC, NULL };
176
177 static const mntopt_t mntopts[] = {
178 /*
179 * option name cancel options default arg flags
180 */
181 { MNTOPT_REMOUNT, NULL, NULL,
182 MO_NODISPLAY, (void *)0 },
183 { MNTOPT_RO, ro_cancel, NULL, 0,
184 (void *)0 },
185 { MNTOPT_RW, rw_cancel, NULL, 0,
186 (void *)0 },
187 { MNTOPT_SUID, suid_cancel, NULL, 0,
188 (void *)0 },
189 { MNTOPT_NOSUID, nosuid_cancel, NULL, 0,
190 (void *)0 },
191 { MNTOPT_DEVICES, devices_cancel, NULL, 0,
192 (void *)0 },
193 { MNTOPT_NODEVICES, nodevices_cancel, NULL, 0,
194 (void *)0 },
195 { MNTOPT_SETUID, setuid_cancel, NULL, 0,
196 (void *)0 },
197 { MNTOPT_NOSETUID, nosetuid_cancel, NULL, 0,
198 (void *)0 },
199 { MNTOPT_NBMAND, nbmand_cancel, NULL, 0,
200 (void *)0 },
201 { MNTOPT_NONBMAND, nonbmand_cancel, NULL, 0,
202 (void *)0 },
203 { MNTOPT_EXEC, exec_cancel, NULL, 0,
204 (void *)0 },
205 { MNTOPT_NOEXEC, noexec_cancel, NULL, 0,
206 (void *)0 },
207 };
208
209 const mntopts_t vfs_mntopts = {
210 sizeof (mntopts) / sizeof (mntopt_t),
211 (mntopt_t *)&mntopts[0]
212 };
213
214 /*
215 * File system operation dispatch functions.
216 */
217
218 int
219 fsop_mount(vfs_t *vfsp, vnode_t *mvp, struct mounta *uap, cred_t *cr)
220 {
221 return (fsh_mount(vfsp, mvp, uap, cr));
222 }
223
224 int
225 fsop_unmount(vfs_t *vfsp, int flag, cred_t *cr)
226 {
227 return (fsh_unmount(vfsp, flag, cr));
228 }
229
230 int
231 fsop_root(vfs_t *vfsp, vnode_t **vpp)
232 {
233 refstr_t *mntpt;
234 int ret = fsh_root(vfsp, vpp);
235 /*
236 * Make sure this root has a path. With lofs, it is possible to have
237 * a NULL mountpoint.
238 */
239 if (ret == 0 && vfsp->vfs_mntpt != NULL && (*vpp)->v_path == NULL) {
240 mntpt = vfs_getmntpoint(vfsp);
241 vn_setpath_str(*vpp, refstr_value(mntpt),
242 strlen(refstr_value(mntpt)));
243 refstr_rele(mntpt);
244 }
245
246 return (ret);
247 }
248
249 int
250 fsop_statfs(vfs_t *vfsp, statvfs64_t *sp)
251 {
252 return (fsh_statfs(vfsp, sp));
253 }
254
255 int
256 fsop_sync(vfs_t *vfsp, short flag, cred_t *cr)
257 {
258 return (*(vfsp)->vfs_op->vfs_sync)(vfsp, flag, cr);
259 }
260
261 int
262 fsop_vget(vfs_t *vfsp, vnode_t **vpp, fid_t *fidp)
263 {
264 /*
265 * In order to handle system attribute fids in a manner
266 * transparent to the underlying fs, we embed the fid for
267 * the sysattr parent object in the sysattr fid and tack on
268 * some extra bytes that only the sysattr layer knows about.
269 *
270 * This guarantees that sysattr fids are larger than other fids
271 * for this vfs. If the vfs supports the sysattr view interface
272 * (as indicated by VFSFT_SYSATTR_VIEWS), we cannot have a size
273 * collision with XATTR_FIDSZ.
274 */
275 if (vfs_has_feature(vfsp, VFSFT_SYSATTR_VIEWS) &&
276 fidp->fid_len == XATTR_FIDSZ)
277 return (xattr_dir_vget(vfsp, vpp, fidp));
278
279 return (fsh_vget(vfsp, vpp, fidp));
280 }
281
282 int
283 fsop_mountroot(vfs_t *vfsp, enum whymountroot reason)
284 {
285 return (*(vfsp)->vfs_op->vfs_mountroot)(vfsp, reason);
286 }
287
288 void
289 fsop_freefs(vfs_t *vfsp)
290 {
291 (*(vfsp)->vfs_op->vfs_freevfs)(vfsp);
292 }
293
294 int
295 fsop_vnstate(vfs_t *vfsp, vnode_t *vp, vntrans_t nstate)
296 {
297 return ((*(vfsp)->vfs_op->vfs_vnstate)(vfsp, vp, nstate));
298 }
299
300 int
301 fsop_sync_by_kind(int fstype, short flag, cred_t *cr)
302 {
303 ASSERT((fstype >= 0) && (fstype < nfstype));
304
305 if (ALLOCATED_VFSSW(&vfssw[fstype]) && VFS_INSTALLED(&vfssw[fstype]))
306 return (*vfssw[fstype].vsw_vfsops.vfs_sync) (NULL, flag, cr);
307 else
308 return (ENOTSUP);
309 }
310
311 /*
312 * File system initialization. vfs_setfsops() must be called from a file
313 * system's init routine.
314 */
315
316 static int
317 fs_copyfsops(const fs_operation_def_t *template, vfsops_t *actual,
318 int *unused_ops)
319 {
320 static const fs_operation_trans_def_t vfs_ops_table[] = {
321 VFSNAME_MOUNT, offsetof(vfsops_t, vfs_mount),
322 fs_nosys, fs_nosys,
323
324 VFSNAME_UNMOUNT, offsetof(vfsops_t, vfs_unmount),
325 fs_nosys, fs_nosys,
326
327 VFSNAME_ROOT, offsetof(vfsops_t, vfs_root),
328 fs_nosys, fs_nosys,
329
330 VFSNAME_STATVFS, offsetof(vfsops_t, vfs_statvfs),
331 fs_nosys, fs_nosys,
332
333 VFSNAME_SYNC, offsetof(vfsops_t, vfs_sync),
334 (fs_generic_func_p) fs_sync,
335 (fs_generic_func_p) fs_sync, /* No errors allowed */
336
337 VFSNAME_VGET, offsetof(vfsops_t, vfs_vget),
338 fs_nosys, fs_nosys,
339
340 VFSNAME_MOUNTROOT, offsetof(vfsops_t, vfs_mountroot),
341 fs_nosys, fs_nosys,
342
343 VFSNAME_FREEVFS, offsetof(vfsops_t, vfs_freevfs),
344 (fs_generic_func_p)fs_freevfs,
345 (fs_generic_func_p)fs_freevfs, /* Shouldn't fail */
346
347 VFSNAME_VNSTATE, offsetof(vfsops_t, vfs_vnstate),
348 (fs_generic_func_p)fs_nosys,
349 (fs_generic_func_p)fs_nosys,
350
351 NULL, 0, NULL, NULL
352 };
353
354 return (fs_build_vector(actual, unused_ops, vfs_ops_table, template));
355 }
356
357 void
358 zfs_boot_init() {
359
360 if (strcmp(rootfs.bo_fstype, MNTTYPE_ZFS) == 0)
361 spa_boot_init();
362 }
363
364 int
365 vfs_setfsops(int fstype, const fs_operation_def_t *template, vfsops_t **actual)
366 {
367 int error;
368 int unused_ops;
369
370 /*
371 * Verify that fstype refers to a valid fs. Note that
372 * 0 is valid since it's used to set "stray" ops.
373 */
374 if ((fstype < 0) || (fstype >= nfstype))
375 return (EINVAL);
376
377 if (!ALLOCATED_VFSSW(&vfssw[fstype]))
378 return (EINVAL);
379
380 /* Set up the operations vector. */
381
382 error = fs_copyfsops(template, &vfssw[fstype].vsw_vfsops, &unused_ops);
383
384 if (error != 0)
385 return (error);
386
387 vfssw[fstype].vsw_flag |= VSW_INSTALLED;
388
389 if (actual != NULL)
390 *actual = &vfssw[fstype].vsw_vfsops;
391
392 #if DEBUG
393 if (unused_ops != 0)
394 cmn_err(CE_WARN, "vfs_setfsops: %s: %d operations supplied "
395 "but not used", vfssw[fstype].vsw_name, unused_ops);
396 #endif
397
398 return (0);
399 }
400
401 int
402 vfs_makefsops(const fs_operation_def_t *template, vfsops_t **actual)
403 {
404 int error;
405 int unused_ops;
406
407 *actual = (vfsops_t *)kmem_alloc(sizeof (vfsops_t), KM_SLEEP);
408
409 error = fs_copyfsops(template, *actual, &unused_ops);
410 if (error != 0) {
411 kmem_free(*actual, sizeof (vfsops_t));
412 *actual = NULL;
413 return (error);
414 }
415
416 return (0);
417 }
418
419 /*
420 * Free a vfsops structure created as a result of vfs_makefsops().
421 * NOTE: For a vfsops structure initialized by vfs_setfsops(), use
422 * vfs_freevfsops_by_type().
423 */
424 void
425 vfs_freevfsops(vfsops_t *vfsops)
426 {
427 kmem_free(vfsops, sizeof (vfsops_t));
428 }
429
430 /*
431 * Since the vfsops structure is part of the vfssw table and wasn't
432 * really allocated, we're not really freeing anything. We keep
433 * the name for consistency with vfs_freevfsops(). We do, however,
434 * need to take care of a little bookkeeping.
435 * NOTE: For a vfsops structure created by vfs_setfsops(), use
436 * vfs_freevfsops_by_type().
437 */
438 int
439 vfs_freevfsops_by_type(int fstype)
440 {
441
442 /* Verify that fstype refers to a loaded fs (and not fsid 0). */
443 if ((fstype <= 0) || (fstype >= nfstype))
444 return (EINVAL);
445
446 WLOCK_VFSSW();
447 if ((vfssw[fstype].vsw_flag & VSW_INSTALLED) == 0) {
448 WUNLOCK_VFSSW();
449 return (EINVAL);
450 }
451
452 vfssw[fstype].vsw_flag &= ~VSW_INSTALLED;
453 WUNLOCK_VFSSW();
454
455 return (0);
456 }
457
458 /* Support routines used to reference vfs_op */
459
460 /* Set the operations vector for a vfs */
461 void
462 vfs_setops(vfs_t *vfsp, vfsops_t *vfsops)
463 {
464 vfsops_t *op;
465
466 ASSERT(vfsp != NULL);
467 ASSERT(vfsops != NULL);
468
469 op = vfsp->vfs_op;
470 membar_consumer();
471 if (vfsp->vfs_femhead == NULL &&
472 casptr(&vfsp->vfs_op, op, vfsops) == op) {
473 return;
474 }
475 fsem_setvfsops(vfsp, vfsops);
476 }
477
478 /* Retrieve the operations vector for a vfs */
479 vfsops_t *
480 vfs_getops(vfs_t *vfsp)
481 {
482 vfsops_t *op;
483
484 ASSERT(vfsp != NULL);
485
486 op = vfsp->vfs_op;
487 membar_consumer();
488 if (vfsp->vfs_femhead == NULL && op == vfsp->vfs_op) {
489 return (op);
490 } else {
491 return (fsem_getvfsops(vfsp));
492 }
493 }
494
495 /*
496 * Returns non-zero (1) if the vfsops matches that of the vfs.
497 * Returns zero (0) if not.
498 */
499 int
500 vfs_matchops(vfs_t *vfsp, vfsops_t *vfsops)
501 {
502 return (vfs_getops(vfsp) == vfsops);
503 }
504
505 /*
506 * Returns non-zero (1) if the file system has installed a non-default,
507 * non-error vfs_sync routine. Returns zero (0) otherwise.
508 */
509 int
510 vfs_can_sync(vfs_t *vfsp)
511 {
512 /* vfs_sync() routine is not the default/error function */
513 return (vfs_getops(vfsp)->vfs_sync != fs_sync);
514 }
515
516 /*
517 * Initialize a vfs structure.
518 */
519 void
520 vfs_init(vfs_t *vfsp, vfsops_t *op, void *data)
521 {
522 /* Other initialization has been moved to vfs_alloc() */
523 vfsp->vfs_count = 0;
524 vfsp->vfs_next = vfsp;
525 vfsp->vfs_prev = vfsp;
526 vfsp->vfs_zone_next = vfsp;
527 vfsp->vfs_zone_prev = vfsp;
528 vfsp->vfs_lofi_minor = 0;
529 sema_init(&vfsp->vfs_reflock, 1, NULL, SEMA_DEFAULT, NULL);
530 vfsimpl_setup(vfsp);
531 vfsp->vfs_data = (data);
532 vfs_setops((vfsp), (op));
533 vfsp->vfs_fshrecord = fsh_fsrec_create();
534 }
535
536 /*
537 * Allocate and initialize the vfs implementation private data
538 * structure, vfs_impl_t.
539 */
540 void
541 vfsimpl_setup(vfs_t *vfsp)
542 {
543 int i;
544
545 if (vfsp->vfs_implp != NULL) {
546 return;
547 }
548
549 vfsp->vfs_implp = kmem_alloc(sizeof (vfs_impl_t), KM_SLEEP);
550 /* Note that these are #define'd in vfs.h */
551 vfsp->vfs_vskap = NULL;
552 vfsp->vfs_fstypevsp = NULL;
553
554 /* Set size of counted array, then zero the array */
555 vfsp->vfs_featureset[0] = VFS_FEATURE_MAXSZ - 1;
556 for (i = 1; i < VFS_FEATURE_MAXSZ; i++) {
557 vfsp->vfs_featureset[i] = 0;
558 }
559 }
560
561 /*
562 * Release the vfs_impl_t structure, if it exists. Some unbundled
563 * filesystems may not use the newer version of vfs and thus
564 * would not contain this implementation private data structure.
565 */
566 void
567 vfsimpl_teardown(vfs_t *vfsp)
568 {
569 vfs_impl_t *vip = vfsp->vfs_implp;
570
571 if (vip == NULL)
572 return;
573
574 kmem_free(vfsp->vfs_implp, sizeof (vfs_impl_t));
575 vfsp->vfs_implp = NULL;
576 }
577
578 /*
579 * VFS system calls: mount, umount, syssync, statfs, fstatfs, statvfs,
580 * fstatvfs, and sysfs moved to common/syscall.
581 */
582
583 /*
584 * Update every mounted file system. We call the vfs_sync operation of
585 * each file system type, passing it a NULL vfsp to indicate that all
586 * mounted file systems of that type should be updated.
587 */
588 void
589 vfs_sync(int flag)
590 {
591 struct vfssw *vswp;
592 RLOCK_VFSSW();
593 for (vswp = &vfssw[1]; vswp < &vfssw[nfstype]; vswp++) {
594 if (ALLOCATED_VFSSW(vswp) && VFS_INSTALLED(vswp)) {
595 vfs_refvfssw(vswp);
596 RUNLOCK_VFSSW();
597 (void) (*vswp->vsw_vfsops.vfs_sync)(NULL, flag,
598 CRED());
599 vfs_unrefvfssw(vswp);
600 RLOCK_VFSSW();
601 }
602 }
603 RUNLOCK_VFSSW();
604 }
605
606 void
607 sync(void)
608 {
609 vfs_sync(0);
610 }
611
612 /*
613 * External routines.
614 */
615
616 krwlock_t vfssw_lock; /* lock accesses to vfssw */
617
618 /*
619 * Lock for accessing the vfs linked list. Initialized in vfs_mountroot(),
620 * but otherwise should be accessed only via vfs_list_lock() and
621 * vfs_list_unlock(). Also used to protect the timestamp for mods to the list.
622 */
623 static krwlock_t vfslist;
624
625 /*
626 * Mount devfs on /devices. This is done right after root is mounted
627 * to provide device access support for the system
628 */
629 static void
630 vfs_mountdevices(void)
631 {
632 struct vfssw *vsw;
633 struct vnode *mvp;
634 struct mounta mounta = { /* fake mounta for devfs_mount() */
635 NULL,
636 NULL,
637 MS_SYSSPACE,
638 NULL,
639 NULL,
640 0,
641 NULL,
642 0
643 };
644
645 /*
646 * _init devfs module to fill in the vfssw
647 */
648 if (modload("fs", "devfs") == -1)
649 panic("Cannot _init devfs module");
650
651 /*
652 * Hold vfs
653 */
654 RLOCK_VFSSW();
655 vsw = vfs_getvfsswbyname("devfs");
656 VFS_INIT(&devices, &vsw->vsw_vfsops, NULL);
657 VFS_HOLD(&devices);
658
659 /*
660 * Locate mount point
661 */
662 if (lookupname("/devices", UIO_SYSSPACE, FOLLOW, NULLVPP, &mvp))
663 panic("Cannot find /devices");
664
665 /*
666 * Perform the mount of /devices
667 */
668 if (VFS_MOUNT(&devices, mvp, &mounta, CRED()))
669 panic("Cannot mount /devices");
670
671 RUNLOCK_VFSSW();
672
673 /*
674 * Set appropriate members and add to vfs list for mnttab display
675 */
676 vfs_setresource(&devices, "/devices", 0);
677 vfs_setmntpoint(&devices, "/devices", 0);
678
679 /*
680 * Hold the root of /devices so it won't go away
681 */
682 if (VFS_ROOT(&devices, &devicesdir))
683 panic("vfs_mountdevices: not devices root");
684
685 if (vfs_lock(&devices) != 0) {
686 VN_RELE(devicesdir);
687 cmn_err(CE_NOTE, "Cannot acquire vfs_lock of /devices");
688 return;
689 }
690
691 if (vn_vfswlock(mvp) != 0) {
692 vfs_unlock(&devices);
693 VN_RELE(devicesdir);
694 cmn_err(CE_NOTE, "Cannot acquire vfswlock of /devices");
695 return;
696 }
697
698 vfs_add(mvp, &devices, 0);
699 vn_vfsunlock(mvp);
700 vfs_unlock(&devices);
701 VN_RELE(devicesdir);
702 }
703
704 /*
705 * mount the first instance of /dev to root and remain mounted
706 */
707 static void
708 vfs_mountdev1(void)
709 {
710 struct vfssw *vsw;
711 struct vnode *mvp;
712 struct mounta mounta = { /* fake mounta for sdev_mount() */
713 NULL,
714 NULL,
715 MS_SYSSPACE | MS_OVERLAY,
716 NULL,
717 NULL,
718 0,
719 NULL,
720 0
721 };
722
723 /*
724 * _init dev module to fill in the vfssw
725 */
726 if (modload("fs", "dev") == -1)
727 cmn_err(CE_PANIC, "Cannot _init dev module\n");
728
729 /*
730 * Hold vfs
731 */
732 RLOCK_VFSSW();
733 vsw = vfs_getvfsswbyname("dev");
734 VFS_INIT(&dev, &vsw->vsw_vfsops, NULL);
735 VFS_HOLD(&dev);
736
737 /*
738 * Locate mount point
739 */
740 if (lookupname("/dev", UIO_SYSSPACE, FOLLOW, NULLVPP, &mvp))
741 cmn_err(CE_PANIC, "Cannot find /dev\n");
742
743 /*
744 * Perform the mount of /dev
745 */
746 if (VFS_MOUNT(&dev, mvp, &mounta, CRED()))
747 cmn_err(CE_PANIC, "Cannot mount /dev 1\n");
748
749 RUNLOCK_VFSSW();
750
751 /*
752 * Set appropriate members and add to vfs list for mnttab display
753 */
754 vfs_setresource(&dev, "/dev", 0);
755 vfs_setmntpoint(&dev, "/dev", 0);
756
757 /*
758 * Hold the root of /dev so it won't go away
759 */
760 if (VFS_ROOT(&dev, &devdir))
761 cmn_err(CE_PANIC, "vfs_mountdev1: not dev root");
762
763 if (vfs_lock(&dev) != 0) {
764 VN_RELE(devdir);
765 cmn_err(CE_NOTE, "Cannot acquire vfs_lock of /dev");
766 return;
767 }
768
769 if (vn_vfswlock(mvp) != 0) {
770 vfs_unlock(&dev);
771 VN_RELE(devdir);
772 cmn_err(CE_NOTE, "Cannot acquire vfswlock of /dev");
773 return;
774 }
775
776 vfs_add(mvp, &dev, 0);
777 vn_vfsunlock(mvp);
778 vfs_unlock(&dev);
779 VN_RELE(devdir);
780 }
781
782 /*
783 * Mount required filesystem. This is done right after root is mounted.
784 */
785 static void
786 vfs_mountfs(char *module, char *spec, char *path)
787 {
788 struct vnode *mvp;
789 struct mounta mounta;
790 vfs_t *vfsp;
791
792 mounta.flags = MS_SYSSPACE | MS_DATA;
793 mounta.fstype = module;
794 mounta.spec = spec;
795 mounta.dir = path;
796 if (lookupname(path, UIO_SYSSPACE, FOLLOW, NULLVPP, &mvp)) {
797 cmn_err(CE_WARN, "Cannot find %s", path);
798 return;
799 }
800 if (domount(NULL, &mounta, mvp, CRED(), &vfsp))
801 cmn_err(CE_WARN, "Cannot mount %s", path);
802 else
803 VFS_RELE(vfsp);
804 VN_RELE(mvp);
805 }
806
807 /*
808 * vfs_mountroot is called by main() to mount the root filesystem.
809 */
810 void
811 vfs_mountroot(void)
812 {
813 struct vnode *rvp = NULL;
814 char *path;
815 size_t plen;
816 struct vfssw *vswp;
817 proc_t *p;
818
819 rw_init(&vfssw_lock, NULL, RW_DEFAULT, NULL);
820 rw_init(&vfslist, NULL, RW_DEFAULT, NULL);
821
822 /*
823 * Alloc the vfs hash bucket array and locks
824 */
825 rvfs_list = kmem_zalloc(vfshsz * sizeof (rvfs_t), KM_SLEEP);
826
827 /*
828 * Call machine-dependent routine "rootconf" to choose a root
829 * file system type.
830 */
831 if (rootconf())
832 panic("vfs_mountroot: cannot mount root");
833 /*
834 * Get vnode for '/'. Set up rootdir, u.u_rdir and u.u_cdir
835 * to point to it. These are used by lookuppn() so that it
836 * knows where to start from ('/' or '.').
837 */
838 vfs_setmntpoint(rootvfs, "/", 0);
839 if (VFS_ROOT(rootvfs, &rootdir))
840 panic("vfs_mountroot: no root vnode");
841
842 /*
843 * At this point, the process tree consists of p0 and possibly some
844 * direct children of p0. (i.e. there are no grandchildren)
845 *
846 * Walk through them all, setting their current directory.
847 */
848 mutex_enter(&pidlock);
849 for (p = practive; p != NULL; p = p->p_next) {
850 ASSERT(p == &p0 || p->p_parent == &p0);
851
852 PTOU(p)->u_cdir = rootdir;
853 VN_HOLD(PTOU(p)->u_cdir);
854 PTOU(p)->u_rdir = NULL;
855 }
856 mutex_exit(&pidlock);
857
858 /*
859 * Setup the global zone's rootvp, now that it exists.
860 */
861 global_zone->zone_rootvp = rootdir;
862 VN_HOLD(global_zone->zone_rootvp);
863
864 /*
865 * Notify the module code that it can begin using the
866 * root filesystem instead of the boot program's services.
867 */
868 modrootloaded = 1;
869
870 /*
871 * Special handling for a ZFS root file system.
872 */
873 zfs_boot_init();
874
875 /*
876 * Set up mnttab information for root
877 */
878 vfs_setresource(rootvfs, rootfs.bo_name, 0);
879
880 /*
881 * Notify cluster software that the root filesystem is available.
882 */
883 clboot_mountroot();
884
885 /* Now that we're all done with the root FS, set up its vopstats */
886 if ((vswp = vfs_getvfsswbyvfsops(vfs_getops(rootvfs))) != NULL) {
887 /* Set flag for statistics collection */
888 if (vswp->vsw_flag & VSW_STATS) {
889 initialize_vopstats(&rootvfs->vfs_vopstats);
890 rootvfs->vfs_flag |= VFS_STATS;
891 rootvfs->vfs_fstypevsp =
892 get_fstype_vopstats(rootvfs, vswp);
893 rootvfs->vfs_vskap = get_vskstat_anchor(rootvfs);
894 }
895 vfs_unrefvfssw(vswp);
896 }
897
898 /*
899 * Mount /devices, /dev instance 1, /system/contract, /etc/mnttab,
900 * /etc/svc/volatile, /etc/dfs/sharetab, /system/object, and /proc.
901 */
902 vfs_mountdevices();
903 vfs_mountdev1();
904
905 vfs_mountfs("ctfs", "ctfs", CTFS_ROOT);
906 vfs_mountfs("proc", "/proc", "/proc");
907 vfs_mountfs("mntfs", "/etc/mnttab", "/etc/mnttab");
908 vfs_mountfs("tmpfs", "/etc/svc/volatile", "/etc/svc/volatile");
909 vfs_mountfs("objfs", "objfs", OBJFS_ROOT);
910
911 if (getzoneid() == GLOBAL_ZONEID) {
912 vfs_mountfs("sharefs", "sharefs", "/etc/dfs/sharetab");
913 }
914
915 #ifdef __sparc
916 /*
917 * This bit of magic can go away when we convert sparc to
918 * the new boot architecture based on ramdisk.
919 *
920 * Booting off a mirrored root volume:
921 * At this point, we have booted and mounted root on a
922 * single component of the mirror. Complete the boot
923 * by configuring SVM and converting the root to the
924 * dev_t of the mirrored root device. This dev_t conversion
925 * only works because the underlying device doesn't change.
926 */
927 if (root_is_svm) {
928 if (svm_rootconf()) {
929 panic("vfs_mountroot: cannot remount root");
930 }
931
932 /*
933 * mnttab should reflect the new root device
934 */
935 vfs_lock_wait(rootvfs);
936 vfs_setresource(rootvfs, rootfs.bo_name, 0);
937 vfs_unlock(rootvfs);
938 }
939 #endif /* __sparc */
940
941 if (strcmp(rootfs.bo_fstype, "zfs") != 0) {
942 /*
943 * Look up the root device via devfs so that a dv_node is
944 * created for it. The vnode is never VN_RELE()ed.
945 * We allocate more than MAXPATHLEN so that the
946 * buffer passed to i_ddi_prompath_to_devfspath() is
947 * exactly MAXPATHLEN (the function expects a buffer
948 * of that length).
949 */
950 plen = strlen("/devices");
951 path = kmem_alloc(plen + MAXPATHLEN, KM_SLEEP);
952 (void) strcpy(path, "/devices");
953
954 if (i_ddi_prompath_to_devfspath(rootfs.bo_name, path + plen)
955 != DDI_SUCCESS ||
956 lookupname(path, UIO_SYSSPACE, FOLLOW, NULLVPP, &rvp)) {
957
958 /* NUL terminate in case "path" has garbage */
959 path[plen + MAXPATHLEN - 1] = '\0';
960 #ifdef DEBUG
961 cmn_err(CE_WARN, "!Cannot lookup root device: %s",
962 path);
963 #endif
964 }
965 kmem_free(path, plen + MAXPATHLEN);
966 }
967
968 vfs_mnttabvp_setup();
969 }
970
971 /*
972 * Check to see if our "block device" is actually a file. If so,
973 * automatically add a lofi device, and keep track of this fact.
974 */
975 static int
976 lofi_add(const char *fsname, struct vfs *vfsp,
977 mntopts_t *mntopts, struct mounta *uap)
978 {
979 int fromspace = (uap->flags & MS_SYSSPACE) ?
980 UIO_SYSSPACE : UIO_USERSPACE;
981 struct lofi_ioctl *li = NULL;
982 struct vnode *vp = NULL;
983 struct pathname pn = { NULL };
984 ldi_ident_t ldi_id;
985 ldi_handle_t ldi_hdl;
986 vfssw_t *vfssw;
987 int minor;
988 int err = 0;
989
990 if ((vfssw = vfs_getvfssw(fsname)) == NULL)
991 return (0);
992
993 if (!(vfssw->vsw_flag & VSW_CANLOFI)) {
994 vfs_unrefvfssw(vfssw);
995 return (0);
996 }
997
998 vfs_unrefvfssw(vfssw);
999 vfssw = NULL;
1000
1001 if (pn_get(uap->spec, fromspace, &pn) != 0)
1002 return (0);
1003
1004 if (lookupname(uap->spec, fromspace, FOLLOW, NULL, &vp) != 0)
1005 goto out;
1006
1007 if (vp->v_type != VREG)
1008 goto out;
1009
1010 /* OK, this is a lofi mount. */
1011
1012 if ((uap->flags & (MS_REMOUNT|MS_GLOBAL)) ||
1013 vfs_optionisset_nolock(mntopts, MNTOPT_SUID, NULL) ||
1014 vfs_optionisset_nolock(mntopts, MNTOPT_SETUID, NULL) ||
1015 vfs_optionisset_nolock(mntopts, MNTOPT_DEVICES, NULL)) {
1016 err = EINVAL;
1017 goto out;
1018 }
1019
1020 ldi_id = ldi_ident_from_anon();
1021 li = kmem_zalloc(sizeof (*li), KM_SLEEP);
1022 (void) strlcpy(li->li_filename, pn.pn_path, MAXPATHLEN);
1023
1024 err = ldi_open_by_name("/dev/lofictl", FREAD | FWRITE, kcred,
1025 &ldi_hdl, ldi_id);
1026
1027 if (err)
1028 goto out2;
1029
1030 err = ldi_ioctl(ldi_hdl, LOFI_MAP_FILE, (intptr_t)li,
1031 FREAD | FWRITE | FKIOCTL, kcred, &minor);
1032
1033 (void) ldi_close(ldi_hdl, FREAD | FWRITE, kcred);
1034
1035 if (!err)
1036 vfsp->vfs_lofi_minor = minor;
1037
1038 out2:
1039 ldi_ident_release(ldi_id);
1040 out:
1041 if (li != NULL)
1042 kmem_free(li, sizeof (*li));
1043 if (vp != NULL)
1044 VN_RELE(vp);
1045 pn_free(&pn);
1046 return (err);
1047 }
1048
1049 static void
1050 lofi_remove(struct vfs *vfsp)
1051 {
1052 struct lofi_ioctl *li = NULL;
1053 ldi_ident_t ldi_id;
1054 ldi_handle_t ldi_hdl;
1055 int err;
1056
1057 if (vfsp->vfs_lofi_minor == 0)
1058 return;
1059
1060 ldi_id = ldi_ident_from_anon();
1061
1062 li = kmem_zalloc(sizeof (*li), KM_SLEEP);
1063 li->li_minor = vfsp->vfs_lofi_minor;
1064 li->li_cleanup = B_TRUE;
1065
1066 err = ldi_open_by_name("/dev/lofictl", FREAD | FWRITE, kcred,
1067 &ldi_hdl, ldi_id);
1068
1069 if (err)
1070 goto out;
1071
1072 err = ldi_ioctl(ldi_hdl, LOFI_UNMAP_FILE_MINOR, (intptr_t)li,
1073 FREAD | FWRITE | FKIOCTL, kcred, NULL);
1074
1075 (void) ldi_close(ldi_hdl, FREAD | FWRITE, kcred);
1076
1077 if (!err)
1078 vfsp->vfs_lofi_minor = 0;
1079
1080 out:
1081 ldi_ident_release(ldi_id);
1082 if (li != NULL)
1083 kmem_free(li, sizeof (*li));
1084 }
1085
1086 /*
1087 * Common mount code. Called from the system call entry point, from autofs,
1088 * nfsv4 trigger mounts, and from pxfs.
1089 *
1090 * Takes the effective file system type, mount arguments, the mount point
1091 * vnode, flags specifying whether the mount is a remount and whether it
1092 * should be entered into the vfs list, and credentials. Fills in its vfspp
1093 * parameter with the mounted file system instance's vfs.
1094 *
1095 * Note that the effective file system type is specified as a string. It may
1096 * be null, in which case it's determined from the mount arguments, and may
1097 * differ from the type specified in the mount arguments; this is a hook to
1098 * allow interposition when instantiating file system instances.
1099 *
1100 * The caller is responsible for releasing its own hold on the mount point
1101 * vp (this routine does its own hold when necessary).
1102 * Also note that for remounts, the mount point vp should be the vnode for
1103 * the root of the file system rather than the vnode that the file system
1104 * is mounted on top of.
1105 */
1106 int
1107 domount(char *fsname, struct mounta *uap, vnode_t *vp, struct cred *credp,
1108 struct vfs **vfspp)
1109 {
1110 struct vfssw *vswp;
1111 vfsops_t *vfsops;
1112 struct vfs *vfsp;
1113 struct vnode *bvp;
1114 dev_t bdev = 0;
1115 mntopts_t mnt_mntopts;
1116 int error = 0;
1117 int copyout_error = 0;
1118 int ovflags;
1119 char *opts = uap->optptr;
1120 char *inargs = opts;
1121 int optlen = uap->optlen;
1122 int remount;
1123 int rdonly;
1124 int nbmand = 0;
1125 int delmip = 0;
1126 int addmip = 0;
1127 int splice = ((uap->flags & MS_NOSPLICE) == 0);
1128 int fromspace = (uap->flags & MS_SYSSPACE) ?
1129 UIO_SYSSPACE : UIO_USERSPACE;
1130 char *resource = NULL, *mountpt = NULL;
1131 refstr_t *oldresource, *oldmntpt;
1132 struct pathname pn, rpn;
1133 vsk_anchor_t *vskap;
1134 char fstname[FSTYPSZ];
1135
1136 /*
1137 * The v_flag value for the mount point vp is permanently set
1138 * to VVFSLOCK so that no one bypasses the vn_vfs*locks routine
1139 * for mount point locking.
1140 */
1141 mutex_enter(&vp->v_lock);
1142 vp->v_flag |= VVFSLOCK;
1143 mutex_exit(&vp->v_lock);
1144
1145 mnt_mntopts.mo_count = 0;
1146 /*
1147 * Find the ops vector to use to invoke the file system-specific mount
1148 * method. If the fsname argument is non-NULL, use it directly.
1149 * Otherwise, dig the file system type information out of the mount
1150 * arguments.
1151 *
1152 * A side effect is to hold the vfssw entry.
1153 *
1154 * Mount arguments can be specified in several ways, which are
1155 * distinguished by flag bit settings. The preferred way is to set
1156 * MS_OPTIONSTR, indicating an 8 argument mount with the file system
1157 * type supplied as a character string and the last two arguments
1158 * being a pointer to a character buffer and the size of the buffer.
1159 * On entry, the buffer holds a null terminated list of options; on
1160 * return, the string is the list of options the file system
1161 * recognized. If MS_DATA is set arguments five and six point to a
1162 * block of binary data which the file system interprets.
1163 * A further wrinkle is that some callers don't set MS_FSS and MS_DATA
1164 * consistently with these conventions. To handle them, we check to
1165 * see whether the pointer to the file system name has a numeric value
1166 * less than 256. If so, we treat it as an index.
1167 */
1168 if (fsname != NULL) {
1169 if ((vswp = vfs_getvfssw(fsname)) == NULL) {
1170 return (EINVAL);
1171 }
1172 } else if (uap->flags & (MS_OPTIONSTR | MS_DATA | MS_FSS)) {
1173 size_t n;
1174 uint_t fstype;
1175
1176 fsname = fstname;
1177
1178 if ((fstype = (uintptr_t)uap->fstype) < 256) {
1179 RLOCK_VFSSW();
1180 if (fstype == 0 || fstype >= nfstype ||
1181 !ALLOCATED_VFSSW(&vfssw[fstype])) {
1182 RUNLOCK_VFSSW();
1183 return (EINVAL);
1184 }
1185 (void) strcpy(fsname, vfssw[fstype].vsw_name);
1186 RUNLOCK_VFSSW();
1187 if ((vswp = vfs_getvfssw(fsname)) == NULL)
1188 return (EINVAL);
1189 } else {
1190 /*
1191 * Handle either kernel or user address space.
1192 */
1193 if (uap->flags & MS_SYSSPACE) {
1194 error = copystr(uap->fstype, fsname,
1195 FSTYPSZ, &n);
1196 } else {
1197 error = copyinstr(uap->fstype, fsname,
1198 FSTYPSZ, &n);
1199 }
1200 if (error) {
1201 if (error == ENAMETOOLONG)
1202 return (EINVAL);
1203 return (error);
1204 }
1205 if ((vswp = vfs_getvfssw(fsname)) == NULL)
1206 return (EINVAL);
1207 }
1208 } else {
1209 if ((vswp = vfs_getvfsswbyvfsops(vfs_getops(rootvfs))) == NULL)
1210 return (EINVAL);
1211 fsname = vswp->vsw_name;
1212 }
1213 if (!VFS_INSTALLED(vswp))
1214 return (EINVAL);
1215
1216 if ((error = secpolicy_fs_allowed_mount(fsname)) != 0) {
1217 vfs_unrefvfssw(vswp);
1218 return (error);
1219 }
1220
1221 vfsops = &vswp->vsw_vfsops;
1222
1223 vfs_copyopttbl(&vswp->vsw_optproto, &mnt_mntopts);
1224 /*
1225 * Fetch mount options and parse them for generic vfs options
1226 */
1227 if (uap->flags & MS_OPTIONSTR) {
1228 /*
1229 * Limit the buffer size
1230 */
1231 if (optlen < 0 || optlen > MAX_MNTOPT_STR) {
1232 error = EINVAL;
1233 goto errout;
1234 }
1235 if ((uap->flags & MS_SYSSPACE) == 0) {
1236 inargs = kmem_alloc(MAX_MNTOPT_STR, KM_SLEEP);
1237 inargs[0] = '\0';
1238 if (optlen) {
1239 error = copyinstr(opts, inargs, (size_t)optlen,
1240 NULL);
1241 if (error) {
1242 goto errout;
1243 }
1244 }
1245 }
1246 vfs_parsemntopts(&mnt_mntopts, inargs, 0);
1247 }
1248 /*
1249 * Flag bits override the options string.
1250 */
1251 if (uap->flags & MS_REMOUNT)
1252 vfs_setmntopt_nolock(&mnt_mntopts, MNTOPT_REMOUNT, NULL, 0, 0);
1253 if (uap->flags & MS_RDONLY)
1254 vfs_setmntopt_nolock(&mnt_mntopts, MNTOPT_RO, NULL, 0, 0);
1255 if (uap->flags & MS_NOSUID)
1256 vfs_setmntopt_nolock(&mnt_mntopts, MNTOPT_NOSUID, NULL, 0, 0);
1257
1258 /*
1259 * Check if this is a remount; must be set in the option string and
1260 * the file system must support a remount option.
1261 */
1262 if (remount = vfs_optionisset_nolock(&mnt_mntopts,
1263 MNTOPT_REMOUNT, NULL)) {
1264 if (!(vswp->vsw_flag & VSW_CANREMOUNT)) {
1265 error = ENOTSUP;
1266 goto errout;
1267 }
1268 uap->flags |= MS_REMOUNT;
1269 }
1270
1271 /*
1272 * uap->flags and vfs_optionisset() should agree.
1273 */
1274 if (rdonly = vfs_optionisset_nolock(&mnt_mntopts, MNTOPT_RO, NULL)) {
1275 uap->flags |= MS_RDONLY;
1276 }
1277 if (vfs_optionisset_nolock(&mnt_mntopts, MNTOPT_NOSUID, NULL)) {
1278 uap->flags |= MS_NOSUID;
1279 }
1280 nbmand = vfs_optionisset_nolock(&mnt_mntopts, MNTOPT_NBMAND, NULL);
1281 ASSERT(splice || !remount);
1282 /*
1283 * If we are splicing the fs into the namespace,
1284 * perform mount point checks.
1285 *
1286 * We want to resolve the path for the mount point to eliminate
1287 * '.' and ".." and symlinks in mount points; we can't do the
1288 * same for the resource string, since it would turn
1289 * "/dev/dsk/c0t0d0s0" into "/devices/pci@...". We need to do
1290 * this before grabbing vn_vfswlock(), because otherwise we
1291 * would deadlock with lookuppn().
1292 */
1293 if (splice) {
1294 ASSERT(vp->v_count > 0);
1295
1296 /*
1297 * Pick up mount point and device from appropriate space.
1298 */
1299 if (pn_get(uap->spec, fromspace, &pn) == 0) {
1300 resource = kmem_alloc(pn.pn_pathlen + 1,
1301 KM_SLEEP);
1302 (void) strcpy(resource, pn.pn_path);
1303 pn_free(&pn);
1304 }
1305 /*
1306 * Do a lookupname prior to taking the
1307 * writelock. Mark this as completed if
1308 * successful for later cleanup and addition to
1309 * the mount in progress table.
1310 */
1311 if ((uap->flags & MS_GLOBAL) == 0 &&
1312 lookupname(uap->spec, fromspace,
1313 FOLLOW, NULL, &bvp) == 0) {
1314 addmip = 1;
1315 }
1316
1317 if ((error = pn_get(uap->dir, fromspace, &pn)) == 0) {
1318 pathname_t *pnp;
1319
1320 if (*pn.pn_path != '/') {
1321 error = EINVAL;
1322 pn_free(&pn);
1323 goto errout;
1324 }
1325 pn_alloc(&rpn);
1326 /*
1327 * Kludge to prevent autofs from deadlocking with
1328 * itself when it calls domount().
1329 *
1330 * If autofs is calling, it is because it is doing
1331 * (autofs) mounts in the process of an NFS mount. A
1332 * lookuppn() here would cause us to block waiting for
1333 * said NFS mount to complete, which can't since this
1334 * is the thread that was supposed to doing it.
1335 */
1336 if (fromspace == UIO_USERSPACE) {
1337 if ((error = lookuppn(&pn, &rpn, FOLLOW, NULL,
1338 NULL)) == 0) {
1339 pnp = &rpn;
1340 } else {
1341 /*
1342 * The file disappeared or otherwise
1343 * became inaccessible since we opened
1344 * it; might as well fail the mount
1345 * since the mount point is no longer
1346 * accessible.
1347 */
1348 pn_free(&rpn);
1349 pn_free(&pn);
1350 goto errout;
1351 }
1352 } else {
1353 pnp = &pn;
1354 }
1355 mountpt = kmem_alloc(pnp->pn_pathlen + 1, KM_SLEEP);
1356 (void) strcpy(mountpt, pnp->pn_path);
1357
1358 /*
1359 * If the addition of the zone's rootpath
1360 * would push us over a total path length
1361 * of MAXPATHLEN, we fail the mount with
1362 * ENAMETOOLONG, which is what we would have
1363 * gotten if we were trying to perform the same
1364 * mount in the global zone.
1365 *
1366 * strlen() doesn't count the trailing
1367 * '\0', but zone_rootpathlen counts both a
1368 * trailing '/' and the terminating '\0'.
1369 */
1370 if ((curproc->p_zone->zone_rootpathlen - 1 +
1371 strlen(mountpt)) > MAXPATHLEN ||
1372 (resource != NULL &&
1373 (curproc->p_zone->zone_rootpathlen - 1 +
1374 strlen(resource)) > MAXPATHLEN)) {
1375 error = ENAMETOOLONG;
1376 }
1377
1378 pn_free(&rpn);
1379 pn_free(&pn);
1380 }
1381
1382 if (error)
1383 goto errout;
1384
1385 /*
1386 * Prevent path name resolution from proceeding past
1387 * the mount point.
1388 */
1389 if (vn_vfswlock(vp) != 0) {
1390 error = EBUSY;
1391 goto errout;
1392 }
1393
1394 /*
1395 * Verify that it's legitimate to establish a mount on
1396 * the prospective mount point.
1397 */
1398 if (vn_mountedvfs(vp) != NULL) {
1399 /*
1400 * The mount point lock was obtained after some
1401 * other thread raced through and established a mount.
1402 */
1403 vn_vfsunlock(vp);
1404 error = EBUSY;
1405 goto errout;
1406 }
1407 if (vp->v_flag & VNOMOUNT) {
1408 vn_vfsunlock(vp);
1409 error = EINVAL;
1410 goto errout;
1411 }
1412 }
1413 if ((uap->flags & (MS_DATA | MS_OPTIONSTR)) == 0) {
1414 uap->dataptr = NULL;
1415 uap->datalen = 0;
1416 }
1417
1418 /*
1419 * If this is a remount, we don't want to create a new VFS.
1420 * Instead, we pass the existing one with a remount flag.
1421 */
1422 if (remount) {
1423 /*
1424 * Confirm that the mount point is the root vnode of the
1425 * file system that is being remounted.
1426 * This can happen if the user specifies a different
1427 * mount point directory pathname in the (re)mount command.
1428 *
1429 * Code below can only be reached if splice is true, so it's
1430 * safe to do vn_vfsunlock() here.
1431 */
1432 if ((vp->v_flag & VROOT) == 0) {
1433 vn_vfsunlock(vp);
1434 error = ENOENT;
1435 goto errout;
1436 }
1437 /*
1438 * Disallow making file systems read-only unless file system
1439 * explicitly allows it in its vfssw. Ignore other flags.
1440 */
1441 if (rdonly && vn_is_readonly(vp) == 0 &&
1442 (vswp->vsw_flag & VSW_CANRWRO) == 0) {
1443 vn_vfsunlock(vp);
1444 error = EINVAL;
1445 goto errout;
1446 }
1447 /*
1448 * Disallow changing the NBMAND disposition of the file
1449 * system on remounts.
1450 */
1451 if ((nbmand && ((vp->v_vfsp->vfs_flag & VFS_NBMAND) == 0)) ||
1452 (!nbmand && (vp->v_vfsp->vfs_flag & VFS_NBMAND))) {
1453 vn_vfsunlock(vp);
1454 error = EINVAL;
1455 goto errout;
1456 }
1457 vfsp = vp->v_vfsp;
1458 ovflags = vfsp->vfs_flag;
1459 vfsp->vfs_flag |= VFS_REMOUNT;
1460 vfsp->vfs_flag &= ~VFS_RDONLY;
1461 } else {
1462 vfsp = vfs_alloc(KM_SLEEP);
1463 VFS_INIT(vfsp, vfsops, NULL);
1464 }
1465
1466 VFS_HOLD(vfsp);
1467
1468 if ((error = lofi_add(fsname, vfsp, &mnt_mntopts, uap)) != 0) {
1469 if (!remount) {
1470 if (splice)
1471 vn_vfsunlock(vp);
1472 vfs_free(vfsp);
1473 } else {
1474 vn_vfsunlock(vp);
1475 VFS_RELE(vfsp);
1476 }
1477 goto errout;
1478 }
1479
1480 /*
1481 * PRIV_SYS_MOUNT doesn't mean you can become root.
1482 */
1483 if (vfsp->vfs_lofi_minor != 0) {
1484 uap->flags |= MS_NOSUID;
1485 vfs_setmntopt_nolock(&mnt_mntopts, MNTOPT_NOSUID, NULL, 0, 0);
1486 }
1487
1488 /*
1489 * The vfs_reflock is not used anymore the code below explicitly
1490 * holds it preventing others accesing it directly.
1491 */
1492 if ((sema_tryp(&vfsp->vfs_reflock) == 0) &&
1493 !(vfsp->vfs_flag & VFS_REMOUNT))
1494 cmn_err(CE_WARN,
1495 "mount type %s couldn't get vfs_reflock", vswp->vsw_name);
1496
1497 /*
1498 * Lock the vfs. If this is a remount we want to avoid spurious umount
1499 * failures that happen as a side-effect of fsflush() and other mount
1500 * and unmount operations that might be going on simultaneously and
1501 * may have locked the vfs currently. To not return EBUSY immediately
1502 * here we use vfs_lock_wait() instead vfs_lock() for the remount case.
1503 */
1504 if (!remount) {
1505 if (error = vfs_lock(vfsp)) {
1506 vfsp->vfs_flag = ovflags;
1507
1508 lofi_remove(vfsp);
1509
1510 if (splice)
1511 vn_vfsunlock(vp);
1512 vfs_free(vfsp);
1513 goto errout;
1514 }
1515 } else {
1516 vfs_lock_wait(vfsp);
1517 }
1518
1519 /*
1520 * Add device to mount in progress table, global mounts require special
1521 * handling. It is possible that we have already done the lookupname
1522 * on a spliced, non-global fs. If so, we don't want to do it again
1523 * since we cannot do a lookupname after taking the
1524 * wlock above. This case is for a non-spliced, non-global filesystem.
1525 */
1526 if (!addmip) {
1527 if ((uap->flags & MS_GLOBAL) == 0 &&
1528 lookupname(uap->spec, fromspace, FOLLOW, NULL, &bvp) == 0) {
1529 addmip = 1;
1530 }
1531 }
1532
1533 if (addmip) {
1534 vnode_t *lvp = NULL;
1535
1536 error = vfs_get_lofi(vfsp, &lvp);
1537 if (error > 0) {
1538 lofi_remove(vfsp);
1539
1540 if (splice)
1541 vn_vfsunlock(vp);
1542 vfs_unlock(vfsp);
1543
1544 if (remount) {
1545 VFS_RELE(vfsp);
1546 } else {
1547 vfs_free(vfsp);
1548 }
1549
1550 goto errout;
1551 } else if (error == -1) {
1552 bdev = bvp->v_rdev;
1553 VN_RELE(bvp);
1554 } else {
1555 bdev = lvp->v_rdev;
1556 VN_RELE(lvp);
1557 VN_RELE(bvp);
1558 }
1559
1560 vfs_addmip(bdev, vfsp);
1561 addmip = 0;
1562 delmip = 1;
1563 }
1564 /*
1565 * Invalidate cached entry for the mount point.
1566 */
1567 if (splice)
1568 dnlc_purge_vp(vp);
1569
1570 /*
1571 * If have an option string but the filesystem doesn't supply a
1572 * prototype options table, create a table with the global
1573 * options and sufficient room to accept all the options in the
1574 * string. Then parse the passed in option string
1575 * accepting all the options in the string. This gives us an
1576 * option table with all the proper cancel properties for the
1577 * global options.
1578 *
1579 * Filesystems that supply a prototype options table are handled
1580 * earlier in this function.
1581 */
1582 if (uap->flags & MS_OPTIONSTR) {
1583 if (!(vswp->vsw_flag & VSW_HASPROTO)) {
1584 mntopts_t tmp_mntopts;
1585
1586 tmp_mntopts.mo_count = 0;
1587 vfs_createopttbl_extend(&tmp_mntopts, inargs,
1588 &mnt_mntopts);
1589 vfs_parsemntopts(&tmp_mntopts, inargs, 1);
1590 vfs_swapopttbl_nolock(&mnt_mntopts, &tmp_mntopts);
1591 vfs_freeopttbl(&tmp_mntopts);
1592 }
1593 }
1594
1595 /*
1596 * Serialize with zone creations.
1597 */
1598 mount_in_progress();
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();
1768 if (splice)
1769 vn_vfsunlock(vp);
1770
1771 if ((error == 0) && (copyout_error == 0)) {
1772 if (!remount) {
1773 /*
1774 * Don't call get_vskstat_anchor() while holding
1775 * locks since it allocates memory and calls
1776 * VFS_STATVFS(). For NFS, the latter can generate
1777 * an over-the-wire call.
1778 */
1779 vskap = get_vskstat_anchor(vfsp);
1780 /* Only take the lock if we have something to do */
1781 if (vskap != NULL) {
1782 vfs_lock_wait(vfsp);
1783 if (vfsp->vfs_flag & VFS_STATS) {
1784 vfsp->vfs_vskap = vskap;
1785 }
1786 vfs_unlock(vfsp);
1787 }
1788 }
1789 /* Return vfsp to caller. */
1790 *vfspp = vfsp;
1791 fsh_exec_create_callbacks(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 (cas64((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 int sync_timeout = 30; /* timeout for syncing a page during panic */
4025 int sync_timeleft; /* portion of sync_timeout remaining */
4026
4027 static int sync_retries = 20; /* number of retries when not making progress */
4028 static int sync_triesleft; /* portion of sync_retries remaining */
4029
4030 static pgcnt_t old_pgcnt, new_pgcnt;
4031 static int new_bufcnt, old_bufcnt;
4032
4033 /*
4034 * Sync all of the mounted filesystems, and then wait for the actual i/o to
4035 * complete. We wait by counting the number of dirty pages and buffers,
4036 * pushing them out using bio_busy() and page_busy(), and then counting again.
4037 * This routine is used during both the uadmin A_SHUTDOWN code as well as
4038 * the SYNC phase of the panic code (see comments in panic.c). It should only
4039 * be used after some higher-level mechanism has quiesced the system so that
4040 * new writes are not being initiated while we are waiting for completion.
4041 *
4042 * To ensure finite running time, our algorithm uses two timeout mechanisms:
4043 * sync_timeleft (a timer implemented by the omnipresent deadman() cyclic), and
4044 * sync_triesleft (a progress counter used by the vfs_syncall() loop below).
4045 * Together these ensure that syncing completes if our i/o paths are stuck.
4046 * The counters are declared above so they can be found easily in the debugger.
4047 *
4048 * The sync_timeleft counter is reset by bio_busy() and page_busy() using the
4049 * vfs_syncprogress() subroutine whenever we make progress through the lists of
4050 * pages and buffers. It is decremented and expired by the deadman() cyclic.
4051 * When vfs_syncall() decides it is done, we disable the deadman() counter by
4052 * setting sync_timeleft to zero. This timer guards against vfs_syncall()
4053 * deadlocking or hanging inside of a broken filesystem or driver routine.
4054 *
4055 * The sync_triesleft counter is updated by vfs_syncall() itself. If we make
4056 * sync_retries consecutive calls to bio_busy() and page_busy() without
4057 * decreasing either the number of dirty buffers or dirty pages below the
4058 * lowest count we have seen so far, we give up and return from vfs_syncall().
4059 *
4060 * Each loop iteration ends with a call to delay() one second to allow time for
4061 * i/o completion and to permit the user time to read our progress messages.
4062 */
4063 void
4064 vfs_syncall(void)
4065 {
4066 if (rootdir == NULL && !modrootloaded)
4067 return; /* panic during boot - no filesystems yet */
4068
4069 printf("syncing file systems...");
4070 vfs_syncprogress();
4071 sync();
4072
4073 vfs_syncprogress();
4074 sync_triesleft = sync_retries;
4075
4076 old_bufcnt = new_bufcnt = INT_MAX;
4077 old_pgcnt = new_pgcnt = ULONG_MAX;
4078
4079 while (sync_triesleft > 0) {
4080 old_bufcnt = MIN(old_bufcnt, new_bufcnt);
4081 old_pgcnt = MIN(old_pgcnt, new_pgcnt);
4082
4083 new_bufcnt = bio_busy(B_TRUE);
4084 new_pgcnt = page_busy(B_TRUE);
4085 vfs_syncprogress();
4086
4087 if (new_bufcnt == 0 && new_pgcnt == 0)
4088 break;
4089
4090 if (new_bufcnt < old_bufcnt || new_pgcnt < old_pgcnt)
4091 sync_triesleft = sync_retries;
4092 else
4093 sync_triesleft--;
4094
4095 if (new_bufcnt)
4096 printf(" [%d]", new_bufcnt);
4097 if (new_pgcnt)
4098 printf(" %lu", new_pgcnt);
4099
4100 delay(hz);
4101 }
4102
4103 if (new_bufcnt != 0 || new_pgcnt != 0)
4104 printf(" done (not all i/o completed)\n");
4105 else
4106 printf(" done\n");
4107
4108 sync_timeleft = 0;
4109 delay(hz);
4110 }
4111
4112 /*
4113 * If we are in the middle of the sync phase of panic, reset sync_timeleft to
4114 * sync_timeout to indicate that we are making progress and the deadman()
4115 * omnipresent cyclic should not yet time us out. Note that it is safe to
4116 * store to sync_timeleft here since the deadman() is firing at high-level
4117 * on top of us. If we are racing with the deadman(), either the deadman()
4118 * will decrement the old value and then we will reset it, or we will
4119 * reset it and then the deadman() will immediately decrement it. In either
4120 * case, correct behavior results.
4121 */
4122 void
4123 vfs_syncprogress(void)
4124 {
4125 if (panicstr)
4126 sync_timeleft = sync_timeout;
4127 }
4128
4129 /*
4130 * Map VFS flags to statvfs flags. These shouldn't really be separate
4131 * flags at all.
4132 */
4133 uint_t
4134 vf_to_stf(uint_t vf)
4135 {
4136 uint_t stf = 0;
4137
4138 if (vf & VFS_RDONLY)
4139 stf |= ST_RDONLY;
4140 if (vf & VFS_NOSETUID)
4141 stf |= ST_NOSUID;
4142 if (vf & VFS_NOTRUNC)
4143 stf |= ST_NOTRUNC;
4144
4145 return (stf);
4146 }
4147
4148 /*
4149 * Entries for (illegal) fstype 0.
4150 */
4151 /* ARGSUSED */
4152 int
4153 vfsstray_sync(struct vfs *vfsp, short arg, struct cred *cr)
4154 {
4155 cmn_err(CE_PANIC, "stray vfs operation");
4156 return (0);
4157 }
4158
4159 /*
4160 * Entries for (illegal) fstype 0.
4161 */
4162 int
4163 vfsstray(void)
4164 {
4165 cmn_err(CE_PANIC, "stray vfs operation");
4166 return (0);
4167 }
4168
4169 /*
4170 * Support for dealing with forced UFS unmount and its interaction with
4171 * LOFS. Could be used by any filesystem.
4172 * See bug 1203132.
4173 */
4174 int
4175 vfs_EIO(void)
4176 {
4177 return (EIO);
4178 }
4179
4180 /*
4181 * We've gotta define the op for sync separately, since the compiler gets
4182 * confused if we mix and match ANSI and normal style prototypes when
4183 * a "short" argument is present and spits out a warning.
4184 */
4185 /*ARGSUSED*/
4186 int
4187 vfs_EIO_sync(struct vfs *vfsp, short arg, struct cred *cr)
4188 {
4189 return (EIO);
4190 }
4191
4192 vfs_t EIO_vfs;
4193 vfsops_t *EIO_vfsops;
4194
4195 /*
4196 * Called from startup() to initialize all loaded vfs's
4197 */
4198 void
4199 vfsinit(void)
4200 {
4201 struct vfssw *vswp;
4202 int error;
4203 extern int vopstats_enabled;
4204 extern void vopstats_startup();
4205
4206 static const fs_operation_def_t EIO_vfsops_template[] = {
4207 VFSNAME_MOUNT, { .error = vfs_EIO },
4208 VFSNAME_UNMOUNT, { .error = vfs_EIO },
4209 VFSNAME_ROOT, { .error = vfs_EIO },
4210 VFSNAME_STATVFS, { .error = vfs_EIO },
4211 VFSNAME_SYNC, { .vfs_sync = vfs_EIO_sync },
4212 VFSNAME_VGET, { .error = vfs_EIO },
4213 VFSNAME_MOUNTROOT, { .error = vfs_EIO },
4214 VFSNAME_FREEVFS, { .error = vfs_EIO },
4215 VFSNAME_VNSTATE, { .error = vfs_EIO },
4216 NULL, NULL
4217 };
4218
4219 static const fs_operation_def_t stray_vfsops_template[] = {
4220 VFSNAME_MOUNT, { .error = vfsstray },
4221 VFSNAME_UNMOUNT, { .error = vfsstray },
4222 VFSNAME_ROOT, { .error = vfsstray },
4223 VFSNAME_STATVFS, { .error = vfsstray },
4224 VFSNAME_SYNC, { .vfs_sync = vfsstray_sync },
4225 VFSNAME_VGET, { .error = vfsstray },
4226 VFSNAME_MOUNTROOT, { .error = vfsstray },
4227 VFSNAME_FREEVFS, { .error = vfsstray },
4228 VFSNAME_VNSTATE, { .error = vfsstray },
4229 NULL, NULL
4230 };
4231
4232 /* Create vfs cache */
4233 vfs_cache = kmem_cache_create("vfs_cache", sizeof (struct vfs),
4234 sizeof (uintptr_t), NULL, NULL, NULL, NULL, NULL, 0);
4235
4236 /* Initialize the vnode cache (file systems may use it during init). */
4237 vn_create_cache();
4238
4239 /* Setup event monitor framework */
4240 fem_init();
4241
4242 /* Initialize the dummy stray file system type. */
4243 error = vfs_setfsops(0, stray_vfsops_template, NULL);
4244
4245 /* Initialize the dummy EIO file system. */
4246 error = vfs_makefsops(EIO_vfsops_template, &EIO_vfsops);
4247 if (error != 0) {
4248 cmn_err(CE_WARN, "vfsinit: bad EIO vfs ops template");
4249 /* Shouldn't happen, but not bad enough to panic */
4250 }
4251
4252 VFS_INIT(&EIO_vfs, EIO_vfsops, (caddr_t)NULL);
4253
4254 /*
4255 * Default EIO_vfs.vfs_flag to VFS_UNMOUNTED so a lookup
4256 * on this vfs can immediately notice it's invalid.
4257 */
4258 EIO_vfs.vfs_flag |= VFS_UNMOUNTED;
4259
4260 /*
4261 * Call the init routines of non-loadable filesystems only.
4262 * Filesystems which are loaded as separate modules will be
4263 * initialized by the module loading code instead.
4264 */
4265
4266 for (vswp = &vfssw[1]; vswp < &vfssw[nfstype]; vswp++) {
4267 RLOCK_VFSSW();
4268 if (vswp->vsw_init != NULL)
4269 (*vswp->vsw_init)(vswp - vfssw, vswp->vsw_name);
4270 RUNLOCK_VFSSW();
4271 }
4272
4273 vopstats_startup();
4274
4275 if (vopstats_enabled) {
4276 /* EIO_vfs can collect stats, but we don't retrieve them */
4277 initialize_vopstats(&EIO_vfs.vfs_vopstats);
4278 EIO_vfs.vfs_fstypevsp = NULL;
4279 EIO_vfs.vfs_vskap = NULL;
4280 EIO_vfs.vfs_flag |= VFS_STATS;
4281 }
4282
4283 xattr_init();
4284
4285 reparse_point_init();
4286 }
4287
4288 vfs_t *
4289 vfs_alloc(int kmflag)
4290 {
4291 vfs_t *vfsp;
4292
4293 vfsp = kmem_cache_alloc(vfs_cache, kmflag);
4294
4295 /*
4296 * Do the simplest initialization here.
4297 * Everything else gets done in vfs_init()
4298 */
4299 bzero(vfsp, sizeof (vfs_t));
4300 return (vfsp);
4301 }
4302
4303 void
4304 vfs_free(vfs_t *vfsp)
4305 {
4306 /*
4307 * One would be tempted to assert that "vfsp->vfs_count == 0".
4308 * The problem is that this gets called out of domount() with
4309 * a partially initialized vfs and a vfs_count of 1. This is
4310 * also called from vfs_rele() with a vfs_count of 0. We can't
4311 * call VFS_RELE() from domount() if VFS_MOUNT() hasn't successfully
4312 * returned. This is because VFS_MOUNT() fully initializes the
4313 * vfs structure and its associated data. VFS_RELE() will call
4314 * VFS_FREEVFS() which may panic the system if the data structures
4315 * aren't fully initialized from a successful VFS_MOUNT()).
4316 */
4317
4318 /* If FEM was in use, make sure everything gets cleaned up */
4319 if (vfsp->vfs_femhead) {
4320 ASSERT(vfsp->vfs_femhead->femh_list == NULL);
4321 mutex_destroy(&vfsp->vfs_femhead->femh_lock);
4322 kmem_free(vfsp->vfs_femhead, sizeof (*(vfsp->vfs_femhead)));
4323 vfsp->vfs_femhead = NULL;
4324 }
4325
4326 /* FSH cleanup */
4327 fsh_fsrec_destroy(vfsp->vfs_fshrecord);
4328 vfsp->vfs_fshrecord = NULL;
4329
4330 if (vfsp->vfs_implp)
4331 vfsimpl_teardown(vfsp);
4332 sema_destroy(&vfsp->vfs_reflock);
4333 kmem_cache_free(vfs_cache, vfsp);
4334 }
4335
4336 /*
4337 * Increments the vfs reference count by one atomically.
4338 */
4339 void
4340 vfs_hold(vfs_t *vfsp)
4341 {
4342 atomic_add_32(&vfsp->vfs_count, 1);
4343 ASSERT(vfsp->vfs_count != 0);
4344 }
4345
4346 /*
4347 * Decrements the vfs reference count by one atomically. When
4348 * vfs reference count becomes zero, it calls the file system
4349 * specific vfs_freevfs() to free up the resources.
4350 */
4351 void
4352 vfs_rele(vfs_t *vfsp)
4353 {
4354 ASSERT(vfsp->vfs_count != 0);
4355 if (atomic_add_32_nv(&vfsp->vfs_count, -1) == 0) {
4356 fsh_exec_destroy_callbacks(vfsp);
4357 VFS_FREEVFS(vfsp);
4358 lofi_remove(vfsp);
4359 if (vfsp->vfs_zone)
4360 zone_rele_ref(&vfsp->vfs_implp->vi_zone_ref,
4361 ZONE_REF_VFS);
4362 vfs_freemnttab(vfsp);
4363 vfs_free(vfsp);
4364 }
4365 }
4366
4367 /*
4368 * Generic operations vector support.
4369 *
4370 * This is used to build operations vectors for both the vfs and vnode.
4371 * It's normally called only when a file system is loaded.
4372 *
4373 * There are many possible algorithms for this, including the following:
4374 *
4375 * (1) scan the list of known operations; for each, see if the file system
4376 * includes an entry for it, and fill it in as appropriate.
4377 *
4378 * (2) set up defaults for all known operations. scan the list of ops
4379 * supplied by the file system; for each which is both supplied and
4380 * known, fill it in.
4381 *
4382 * (3) sort the lists of known ops & supplied ops; scan the list, filling
4383 * in entries as we go.
4384 *
4385 * we choose (1) for simplicity, and because performance isn't critical here.
4386 * note that (2) could be sped up using a precomputed hash table on known ops.
4387 * (3) could be faster than either, but only if the lists were very large or
4388 * supplied in sorted order.
4389 *
4390 */
4391
4392 int
4393 fs_build_vector(void *vector, int *unused_ops,
4394 const fs_operation_trans_def_t *translation,
4395 const fs_operation_def_t *operations)
4396 {
4397 int i, num_trans, num_ops, used;
4398
4399 /*
4400 * Count the number of translations and the number of supplied
4401 * operations.
4402 */
4403
4404 {
4405 const fs_operation_trans_def_t *p;
4406
4407 for (num_trans = 0, p = translation;
4408 p->name != NULL;
4409 num_trans++, p++)
4410 ;
4411 }
4412
4413 {
4414 const fs_operation_def_t *p;
4415
4416 for (num_ops = 0, p = operations;
4417 p->name != NULL;
4418 num_ops++, p++)
4419 ;
4420 }
4421
4422 /* Walk through each operation known to our caller. There will be */
4423 /* one entry in the supplied "translation table" for each. */
4424
4425 used = 0;
4426
4427 for (i = 0; i < num_trans; i++) {
4428 int j, found;
4429 char *curname;
4430 fs_generic_func_p result;
4431 fs_generic_func_p *location;
4432
4433 curname = translation[i].name;
4434
4435 /* Look for a matching operation in the list supplied by the */
4436 /* file system. */
4437
4438 found = 0;
4439
4440 for (j = 0; j < num_ops; j++) {
4441 if (strcmp(operations[j].name, curname) == 0) {
4442 used++;
4443 found = 1;
4444 break;
4445 }
4446 }
4447
4448 /*
4449 * If the file system is using a "placeholder" for default
4450 * or error functions, grab the appropriate function out of
4451 * the translation table. If the file system didn't supply
4452 * this operation at all, use the default function.
4453 */
4454
4455 if (found) {
4456 result = operations[j].func.fs_generic;
4457 if (result == fs_default) {
4458 result = translation[i].defaultFunc;
4459 } else if (result == fs_error) {
4460 result = translation[i].errorFunc;
4461 } else if (result == NULL) {
4462 /* Null values are PROHIBITED */
4463 return (EINVAL);
4464 }
4465 } else {
4466 result = translation[i].defaultFunc;
4467 }
4468
4469 /* Now store the function into the operations vector. */
4470
4471 location = (fs_generic_func_p *)
4472 (((char *)vector) + translation[i].offset);
4473
4474 *location = result;
4475 }
4476
4477 *unused_ops = num_ops - used;
4478
4479 return (0);
4480 }
4481
4482 /* Placeholder functions, should never be called. */
4483
4484 int
4485 fs_error(void)
4486 {
4487 cmn_err(CE_PANIC, "fs_error called");
4488 return (0);
4489 }
4490
4491 int
4492 fs_default(void)
4493 {
4494 cmn_err(CE_PANIC, "fs_default called");
4495 return (0);
4496 }
4497
4498 #ifdef __sparc
4499
4500 /*
4501 * Part of the implementation of booting off a mirrored root
4502 * involves a change of dev_t for the root device. To
4503 * accomplish this, first remove the existing hash table
4504 * entry for the root device, convert to the new dev_t,
4505 * then re-insert in the hash table at the head of the list.
4506 */
4507 void
4508 vfs_root_redev(vfs_t *vfsp, dev_t ndev, int fstype)
4509 {
4510 vfs_list_lock();
4511
4512 vfs_hash_remove(vfsp);
4513
4514 vfsp->vfs_dev = ndev;
4515 vfs_make_fsid(&vfsp->vfs_fsid, ndev, fstype);
4516
4517 vfs_hash_add(vfsp, 1);
4518
4519 vfs_list_unlock();
4520 }
4521
4522 #else /* x86 NEWBOOT */
4523
4524 #if defined(__x86)
4525 extern int hvmboot_rootconf();
4526 #endif /* __x86 */
4527
4528 extern ib_boot_prop_t *iscsiboot_prop;
4529
4530 int
4531 rootconf()
4532 {
4533 int error;
4534 struct vfssw *vsw;
4535 extern void pm_init();
4536 char *fstyp, *fsmod;
4537 int ret = -1;
4538
4539 getrootfs(&fstyp, &fsmod);
4540
4541 #if defined(__x86)
4542 /*
4543 * hvmboot_rootconf() is defined in the hvm_bootstrap misc module,
4544 * which lives in /platform/i86hvm, and hence is only available when
4545 * booted in an x86 hvm environment. If the hvm_bootstrap misc module
4546 * is not available then the modstub for this function will return 0.
4547 * If the hvm_bootstrap misc module is available it will be loaded
4548 * and hvmboot_rootconf() will be invoked.
4549 */
4550 if (error = hvmboot_rootconf())
4551 return (error);
4552 #endif /* __x86 */
4553
4554 if (error = clboot_rootconf())
4555 return (error);
4556
4557 if (modload("fs", fsmod) == -1)
4558 panic("Cannot _init %s module", fsmod);
4559
4560 RLOCK_VFSSW();
4561 vsw = vfs_getvfsswbyname(fstyp);
4562 RUNLOCK_VFSSW();
4563 if (vsw == NULL) {
4564 cmn_err(CE_CONT, "Cannot find %s filesystem\n", fstyp);
4565 return (ENXIO);
4566 }
4567 VFS_INIT(rootvfs, &vsw->vsw_vfsops, 0);
4568 VFS_HOLD(rootvfs);
4569
4570 /* always mount readonly first */
4571 rootvfs->vfs_flag |= VFS_RDONLY;
4572
4573 pm_init();
4574
4575 if (netboot && iscsiboot_prop) {
4576 cmn_err(CE_WARN, "NFS boot and iSCSI boot"
4577 " shouldn't happen in the same time");
4578 return (EINVAL);
4579 }
4580
4581 if (netboot || iscsiboot_prop) {
4582 ret = strplumb();
4583 if (ret != 0) {
4584 cmn_err(CE_WARN, "Cannot plumb network device %d", ret);
4585 return (EFAULT);
4586 }
4587 }
4588
4589 if ((ret == 0) && iscsiboot_prop) {
4590 ret = modload("drv", "iscsi");
4591 /* -1 indicates fail */
4592 if (ret == -1) {
4593 cmn_err(CE_WARN, "Failed to load iscsi module");
4594 iscsi_boot_prop_free();
4595 return (EINVAL);
4596 } else {
4597 if (!i_ddi_attach_pseudo_node("iscsi")) {
4598 cmn_err(CE_WARN,
4599 "Failed to attach iscsi driver");
4600 iscsi_boot_prop_free();
4601 return (ENODEV);
4602 }
4603 }
4604 }
4605
4606 error = VFS_MOUNTROOT(rootvfs, ROOT_INIT);
4607 vfs_unrefvfssw(vsw);
4608 rootdev = rootvfs->vfs_dev;
4609
4610 if (error)
4611 cmn_err(CE_CONT, "Cannot mount root on %s fstype %s\n",
4612 rootfs.bo_name, fstyp);
4613 else
4614 cmn_err(CE_CONT, "?root on %s fstype %s\n",
4615 rootfs.bo_name, fstyp);
4616 return (error);
4617 }
4618
4619 /*
4620 * XXX this is called by nfs only and should probably be removed
4621 * If booted with ASKNAME, prompt on the console for a filesystem
4622 * name and return it.
4623 */
4624 void
4625 getfsname(char *askfor, char *name, size_t namelen)
4626 {
4627 if (boothowto & RB_ASKNAME) {
4628 printf("%s name: ", askfor);
4629 console_gets(name, namelen);
4630 }
4631 }
4632
4633 /*
4634 * Init the root filesystem type (rootfs.bo_fstype) from the "fstype"
4635 * property.
4636 *
4637 * Filesystem types starting with the prefix "nfs" are diskless clients;
4638 * init the root filename name (rootfs.bo_name), too.
4639 *
4640 * If we are booting via NFS we currently have these options:
4641 * nfs - dynamically choose NFS V2, V3, or V4 (default)
4642 * nfs2 - force NFS V2
4643 * nfs3 - force NFS V3
4644 * nfs4 - force NFS V4
4645 * Because we need to maintain backward compatibility with the naming
4646 * convention that the NFS V2 filesystem name is "nfs" (see vfs_conf.c)
4647 * we need to map "nfs" => "nfsdyn" and "nfs2" => "nfs". The dynamic
4648 * nfs module will map the type back to either "nfs", "nfs3", or "nfs4".
4649 * This is only for root filesystems, all other uses such as cachefs
4650 * will expect that "nfs" == NFS V2.
4651 */
4652 static void
4653 getrootfs(char **fstypp, char **fsmodp)
4654 {
4655 extern char *strplumb_get_netdev_path(void);
4656 char *propstr = NULL;
4657
4658 /*
4659 * Check fstype property; for diskless it should be one of "nfs",
4660 * "nfs2", "nfs3" or "nfs4".
4661 */
4662 if (ddi_prop_lookup_string(DDI_DEV_T_ANY, ddi_root_node(),
4663 DDI_PROP_DONTPASS, "fstype", &propstr)
4664 == DDI_SUCCESS) {
4665 (void) strncpy(rootfs.bo_fstype, propstr, BO_MAXFSNAME);
4666 ddi_prop_free(propstr);
4667
4668 /*
4669 * if the boot property 'fstype' is not set, but 'zfs-bootfs' is set,
4670 * assume the type of this root filesystem is 'zfs'.
4671 */
4672 } else if (ddi_prop_lookup_string(DDI_DEV_T_ANY, ddi_root_node(),
4673 DDI_PROP_DONTPASS, "zfs-bootfs", &propstr)
4674 == DDI_SUCCESS) {
4675 (void) strncpy(rootfs.bo_fstype, "zfs", BO_MAXFSNAME);
4676 ddi_prop_free(propstr);
4677 }
4678
4679 if (strncmp(rootfs.bo_fstype, "nfs", 3) != 0) {
4680 *fstypp = *fsmodp = rootfs.bo_fstype;
4681 return;
4682 }
4683
4684 ++netboot;
4685
4686 if (strcmp(rootfs.bo_fstype, "nfs2") == 0)
4687 (void) strcpy(rootfs.bo_fstype, "nfs");
4688 else if (strcmp(rootfs.bo_fstype, "nfs") == 0)
4689 (void) strcpy(rootfs.bo_fstype, "nfsdyn");
4690
4691 /*
4692 * check if path to network interface is specified in bootpath
4693 * or by a hypervisor domain configuration file.
4694 * XXPV - enable strlumb_get_netdev_path()
4695 */
4696 if (ddi_prop_exists(DDI_DEV_T_ANY, ddi_root_node(), DDI_PROP_DONTPASS,
4697 "xpv-nfsroot")) {
4698 (void) strcpy(rootfs.bo_name, "/xpvd/xnf@0");
4699 } else if (ddi_prop_lookup_string(DDI_DEV_T_ANY, ddi_root_node(),
4700 DDI_PROP_DONTPASS, "bootpath", &propstr)
4701 == DDI_SUCCESS) {
4702 (void) strncpy(rootfs.bo_name, propstr, BO_MAXOBJNAME);
4703 ddi_prop_free(propstr);
4704 } else {
4705 /* attempt to determine netdev_path via boot_mac address */
4706 netdev_path = strplumb_get_netdev_path();
4707 if (netdev_path == NULL)
4708 panic("cannot find boot network interface");
4709 (void) strncpy(rootfs.bo_name, netdev_path, BO_MAXOBJNAME);
4710 }
4711 *fstypp = rootfs.bo_fstype;
4712 *fsmodp = "nfs";
4713 }
4714 #endif
4715
4716 /*
4717 * VFS feature routines
4718 */
4719
4720 #define VFTINDEX(feature) (((feature) >> 32) & 0xFFFFFFFF)
4721 #define VFTBITS(feature) ((feature) & 0xFFFFFFFFLL)
4722
4723 /* Register a feature in the vfs */
4724 void
4725 vfs_set_feature(vfs_t *vfsp, vfs_feature_t feature)
4726 {
4727 /* Note that vfs_featureset[] is found in *vfsp->vfs_implp */
4728 if (vfsp->vfs_implp == NULL)
4729 return;
4730
4731 vfsp->vfs_featureset[VFTINDEX(feature)] |= VFTBITS(feature);
4732 }
4733
4734 void
4735 vfs_clear_feature(vfs_t *vfsp, vfs_feature_t feature)
4736 {
4737 /* Note that vfs_featureset[] is found in *vfsp->vfs_implp */
4738 if (vfsp->vfs_implp == NULL)
4739 return;
4740 vfsp->vfs_featureset[VFTINDEX(feature)] &= VFTBITS(~feature);
4741 }
4742
4743 /*
4744 * Query a vfs for a feature.
4745 * Returns 1 if feature is present, 0 if not
4746 */
4747 int
4748 vfs_has_feature(vfs_t *vfsp, vfs_feature_t feature)
4749 {
4750 int ret = 0;
4751
4752 /* Note that vfs_featureset[] is found in *vfsp->vfs_implp */
4753 if (vfsp->vfs_implp == NULL)
4754 return (ret);
4755
4756 if (vfsp->vfs_featureset[VFTINDEX(feature)] & VFTBITS(feature))
4757 ret = 1;
4758
4759 return (ret);
4760 }
4761
4762 /*
4763 * Propagate feature set from one vfs to another
4764 */
4765 void
4766 vfs_propagate_features(vfs_t *from, vfs_t *to)
4767 {
4768 int i;
4769
4770 if (to->vfs_implp == NULL || from->vfs_implp == NULL)
4771 return;
4772
4773 for (i = 1; i <= to->vfs_featureset[0]; i++) {
4774 to->vfs_featureset[i] = from->vfs_featureset[i];
4775 }
4776 }
4777
4778 #define LOFINODE_PATH "/dev/lofi/%d"
4779
4780 /*
4781 * Return the vnode for the lofi node if there's a lofi mount in place.
4782 * Returns -1 when there's no lofi node, 0 on success, and > 0 on
4783 * failure.
4784 */
4785 int
4786 vfs_get_lofi(vfs_t *vfsp, vnode_t **vpp)
4787 {
4788 char *path = NULL;
4789 int strsize;
4790 int err;
4791
4792 if (vfsp->vfs_lofi_minor == 0) {
4793 *vpp = NULL;
4794 return (-1);
4795 }
4796
4797 strsize = snprintf(NULL, 0, LOFINODE_PATH, vfsp->vfs_lofi_minor);
4798 path = kmem_alloc(strsize + 1, KM_SLEEP);
4799 (void) snprintf(path, strsize + 1, LOFINODE_PATH, vfsp->vfs_lofi_minor);
4800
4801 /*
4802 * We may be inside a zone, so we need to use the /dev path, but
4803 * it's created asynchronously, so we wait here.
4804 */
4805 for (;;) {
4806 err = lookupname(path, UIO_SYSSPACE, FOLLOW, NULLVPP, vpp);
4807
4808 if (err != ENOENT)
4809 break;
4810
4811 if ((err = delay_sig(hz / 8)) == EINTR)
4812 break;
4813 }
4814
4815 if (err)
4816 *vpp = NULL;
4817
4818 kmem_free(path, strsize + 1);
4819 return (err);
4820 }