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