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7127 remove -Wno-missing-braces from Makefile.uts
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--- old/usr/src/uts/common/fs/zfs/zfs_ctldir.c
+++ new/usr/src/uts/common/fs/zfs/zfs_ctldir.c
1 1 /*
2 2 * CDDL HEADER START
3 3 *
4 4 * The contents of this file are subject to the terms of the
5 5 * Common Development and Distribution License (the "License").
6 6 * You may not use this file except in compliance with the License.
7 7 *
8 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 9 * or http://www.opensolaris.org/os/licensing.
10 10 * See the License for the specific language governing permissions
11 11 * and limitations under the License.
12 12 *
13 13 * When distributing Covered Code, include this CDDL HEADER in each
14 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 15 * If applicable, add the following below this CDDL HEADER, with the
16 16 * fields enclosed by brackets "[]" replaced with your own identifying
17 17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 18 *
19 19 * CDDL HEADER END
20 20 */
21 21 /*
22 22 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
23 23 * Copyright (c) 2012, 2015 by Delphix. All rights reserved.
24 24 * Copyright 2015, OmniTI Computer Consulting, Inc. All rights reserved.
25 25 */
26 26
27 27 /*
28 28 * ZFS control directory (a.k.a. ".zfs")
29 29 *
30 30 * This directory provides a common location for all ZFS meta-objects.
31 31 * Currently, this is only the 'snapshot' directory, but this may expand in the
32 32 * future. The elements are built using the GFS primitives, as the hierarchy
33 33 * does not actually exist on disk.
34 34 *
35 35 * For 'snapshot', we don't want to have all snapshots always mounted, because
36 36 * this would take up a huge amount of space in /etc/mnttab. We have three
37 37 * types of objects:
38 38 *
39 39 * ctldir ------> snapshotdir -------> snapshot
40 40 * |
41 41 * |
42 42 * V
43 43 * mounted fs
44 44 *
45 45 * The 'snapshot' node contains just enough information to lookup '..' and act
46 46 * as a mountpoint for the snapshot. Whenever we lookup a specific snapshot, we
47 47 * perform an automount of the underlying filesystem and return the
48 48 * corresponding vnode.
49 49 *
50 50 * All mounts are handled automatically by the kernel, but unmounts are
51 51 * (currently) handled from user land. The main reason is that there is no
52 52 * reliable way to auto-unmount the filesystem when it's "no longer in use".
53 53 * When the user unmounts a filesystem, we call zfsctl_unmount(), which
54 54 * unmounts any snapshots within the snapshot directory.
55 55 *
56 56 * The '.zfs', '.zfs/snapshot', and all directories created under
57 57 * '.zfs/snapshot' (ie: '.zfs/snapshot/<snapname>') are all GFS nodes and
58 58 * share the same vfs_t as the head filesystem (what '.zfs' lives under).
59 59 *
60 60 * File systems mounted ontop of the GFS nodes '.zfs/snapshot/<snapname>'
61 61 * (ie: snapshots) are ZFS nodes and have their own unique vfs_t.
62 62 * However, vnodes within these mounted on file systems have their v_vfsp
63 63 * fields set to the head filesystem to make NFS happy (see
64 64 * zfsctl_snapdir_lookup()). We VFS_HOLD the head filesystem's vfs_t
65 65 * so that it cannot be freed until all snapshots have been unmounted.
66 66 */
67 67
68 68 #include <fs/fs_subr.h>
69 69 #include <sys/zfs_ctldir.h>
70 70 #include <sys/zfs_ioctl.h>
71 71 #include <sys/zfs_vfsops.h>
72 72 #include <sys/vfs_opreg.h>
73 73 #include <sys/gfs.h>
74 74 #include <sys/stat.h>
75 75 #include <sys/dmu.h>
76 76 #include <sys/dsl_destroy.h>
77 77 #include <sys/dsl_deleg.h>
78 78 #include <sys/mount.h>
79 79 #include <sys/sunddi.h>
80 80
81 81 #include "zfs_namecheck.h"
82 82
83 83 typedef struct zfsctl_node {
84 84 gfs_dir_t zc_gfs_private;
85 85 uint64_t zc_id;
86 86 timestruc_t zc_cmtime; /* ctime and mtime, always the same */
87 87 } zfsctl_node_t;
88 88
89 89 typedef struct zfsctl_snapdir {
90 90 zfsctl_node_t sd_node;
91 91 kmutex_t sd_lock;
92 92 avl_tree_t sd_snaps;
93 93 } zfsctl_snapdir_t;
94 94
95 95 typedef struct {
96 96 char *se_name;
97 97 vnode_t *se_root;
98 98 avl_node_t se_node;
99 99 } zfs_snapentry_t;
100 100
101 101 static int
102 102 snapentry_compare(const void *a, const void *b)
103 103 {
104 104 const zfs_snapentry_t *sa = a;
105 105 const zfs_snapentry_t *sb = b;
106 106 int ret = strcmp(sa->se_name, sb->se_name);
107 107
108 108 if (ret < 0)
109 109 return (-1);
110 110 else if (ret > 0)
111 111 return (1);
112 112 else
113 113 return (0);
114 114 }
115 115
116 116 vnodeops_t *zfsctl_ops_root;
117 117 vnodeops_t *zfsctl_ops_snapdir;
118 118 vnodeops_t *zfsctl_ops_snapshot;
119 119 vnodeops_t *zfsctl_ops_shares;
120 120 vnodeops_t *zfsctl_ops_shares_dir;
121 121
122 122 static const fs_operation_def_t zfsctl_tops_root[];
123 123 static const fs_operation_def_t zfsctl_tops_snapdir[];
124 124 static const fs_operation_def_t zfsctl_tops_snapshot[];
125 125 static const fs_operation_def_t zfsctl_tops_shares[];
126 126
127 127 static vnode_t *zfsctl_mknode_snapdir(vnode_t *);
128 128 static vnode_t *zfsctl_mknode_shares(vnode_t *);
129 129 static vnode_t *zfsctl_snapshot_mknode(vnode_t *, uint64_t objset);
130 130 static int zfsctl_unmount_snap(zfs_snapentry_t *, int, cred_t *);
131 131
132 132 static gfs_opsvec_t zfsctl_opsvec[] = {
133 133 { ".zfs", zfsctl_tops_root, &zfsctl_ops_root },
134 134 { ".zfs/snapshot", zfsctl_tops_snapdir, &zfsctl_ops_snapdir },
135 135 { ".zfs/snapshot/vnode", zfsctl_tops_snapshot, &zfsctl_ops_snapshot },
136 136 { ".zfs/shares", zfsctl_tops_shares, &zfsctl_ops_shares_dir },
137 137 { ".zfs/shares/vnode", zfsctl_tops_shares, &zfsctl_ops_shares },
138 138 { NULL }
139 139 };
140 140
141 141 /*
142 142 * Root directory elements. We only have two entries
143 143 * snapshot and shares.
144 144 */
145 145 static gfs_dirent_t zfsctl_root_entries[] = {
146 146 { "snapshot", zfsctl_mknode_snapdir, GFS_CACHE_VNODE },
147 147 { "shares", zfsctl_mknode_shares, GFS_CACHE_VNODE },
148 148 { NULL }
149 149 };
150 150
151 151 /* include . and .. in the calculation */
152 152 #define NROOT_ENTRIES ((sizeof (zfsctl_root_entries) / \
153 153 sizeof (gfs_dirent_t)) + 1)
154 154
155 155
156 156 /*
157 157 * Initialize the various GFS pieces we'll need to create and manipulate .zfs
158 158 * directories. This is called from the ZFS init routine, and initializes the
159 159 * vnode ops vectors that we'll be using.
160 160 */
161 161 void
162 162 zfsctl_init(void)
163 163 {
164 164 VERIFY(gfs_make_opsvec(zfsctl_opsvec) == 0);
165 165 }
166 166
167 167 void
168 168 zfsctl_fini(void)
169 169 {
170 170 /*
171 171 * Remove vfsctl vnode ops
172 172 */
173 173 if (zfsctl_ops_root)
174 174 vn_freevnodeops(zfsctl_ops_root);
175 175 if (zfsctl_ops_snapdir)
176 176 vn_freevnodeops(zfsctl_ops_snapdir);
177 177 if (zfsctl_ops_snapshot)
178 178 vn_freevnodeops(zfsctl_ops_snapshot);
179 179 if (zfsctl_ops_shares)
180 180 vn_freevnodeops(zfsctl_ops_shares);
181 181 if (zfsctl_ops_shares_dir)
182 182 vn_freevnodeops(zfsctl_ops_shares_dir);
183 183
184 184 zfsctl_ops_root = NULL;
185 185 zfsctl_ops_snapdir = NULL;
186 186 zfsctl_ops_snapshot = NULL;
187 187 zfsctl_ops_shares = NULL;
188 188 zfsctl_ops_shares_dir = NULL;
189 189 }
190 190
191 191 boolean_t
192 192 zfsctl_is_node(vnode_t *vp)
193 193 {
194 194 return (vn_matchops(vp, zfsctl_ops_root) ||
195 195 vn_matchops(vp, zfsctl_ops_snapdir) ||
196 196 vn_matchops(vp, zfsctl_ops_snapshot) ||
197 197 vn_matchops(vp, zfsctl_ops_shares) ||
198 198 vn_matchops(vp, zfsctl_ops_shares_dir));
199 199
200 200 }
201 201
202 202 /*
203 203 * Return the inode number associated with the 'snapshot' or
204 204 * 'shares' directory.
205 205 */
206 206 /* ARGSUSED */
207 207 static ino64_t
208 208 zfsctl_root_inode_cb(vnode_t *vp, int index)
209 209 {
210 210 zfsvfs_t *zfsvfs = vp->v_vfsp->vfs_data;
211 211
212 212 ASSERT(index <= 2);
213 213
214 214 if (index == 0)
215 215 return (ZFSCTL_INO_SNAPDIR);
216 216
217 217 return (zfsvfs->z_shares_dir);
218 218 }
219 219
220 220 /*
221 221 * Create the '.zfs' directory. This directory is cached as part of the VFS
222 222 * structure. This results in a hold on the vfs_t. The code in zfs_umount()
223 223 * therefore checks against a vfs_count of 2 instead of 1. This reference
224 224 * is removed when the ctldir is destroyed in the unmount.
225 225 */
226 226 void
227 227 zfsctl_create(zfsvfs_t *zfsvfs)
228 228 {
229 229 vnode_t *vp, *rvp;
230 230 zfsctl_node_t *zcp;
231 231 uint64_t crtime[2];
232 232
233 233 ASSERT(zfsvfs->z_ctldir == NULL);
234 234
235 235 vp = gfs_root_create(sizeof (zfsctl_node_t), zfsvfs->z_vfs,
236 236 zfsctl_ops_root, ZFSCTL_INO_ROOT, zfsctl_root_entries,
237 237 zfsctl_root_inode_cb, MAXNAMELEN, NULL, NULL);
238 238 zcp = vp->v_data;
239 239 zcp->zc_id = ZFSCTL_INO_ROOT;
240 240
241 241 VERIFY(VFS_ROOT(zfsvfs->z_vfs, &rvp) == 0);
242 242 VERIFY(0 == sa_lookup(VTOZ(rvp)->z_sa_hdl, SA_ZPL_CRTIME(zfsvfs),
243 243 &crtime, sizeof (crtime)));
244 244 ZFS_TIME_DECODE(&zcp->zc_cmtime, crtime);
245 245 VN_RELE(rvp);
246 246
247 247 /*
248 248 * We're only faking the fact that we have a root of a filesystem for
249 249 * the sake of the GFS interfaces. Undo the flag manipulation it did
250 250 * for us.
251 251 */
252 252 vp->v_flag &= ~(VROOT | VNOCACHE | VNOMAP | VNOSWAP | VNOMOUNT);
253 253
254 254 zfsvfs->z_ctldir = vp;
255 255 }
256 256
257 257 /*
258 258 * Destroy the '.zfs' directory. Only called when the filesystem is unmounted.
259 259 * There might still be more references if we were force unmounted, but only
260 260 * new zfs_inactive() calls can occur and they don't reference .zfs
261 261 */
262 262 void
263 263 zfsctl_destroy(zfsvfs_t *zfsvfs)
264 264 {
265 265 VN_RELE(zfsvfs->z_ctldir);
266 266 zfsvfs->z_ctldir = NULL;
267 267 }
268 268
269 269 /*
270 270 * Given a root znode, retrieve the associated .zfs directory.
271 271 * Add a hold to the vnode and return it.
272 272 */
273 273 vnode_t *
274 274 zfsctl_root(znode_t *zp)
275 275 {
276 276 ASSERT(zfs_has_ctldir(zp));
277 277 VN_HOLD(zp->z_zfsvfs->z_ctldir);
278 278 return (zp->z_zfsvfs->z_ctldir);
279 279 }
280 280
281 281 /*
282 282 * Common open routine. Disallow any write access.
283 283 */
284 284 /* ARGSUSED */
285 285 static int
286 286 zfsctl_common_open(vnode_t **vpp, int flags, cred_t *cr, caller_context_t *ct)
287 287 {
288 288 if (flags & FWRITE)
289 289 return (SET_ERROR(EACCES));
290 290
291 291 return (0);
292 292 }
293 293
294 294 /*
295 295 * Common close routine. Nothing to do here.
296 296 */
297 297 /* ARGSUSED */
298 298 static int
299 299 zfsctl_common_close(vnode_t *vpp, int flags, int count, offset_t off,
300 300 cred_t *cr, caller_context_t *ct)
301 301 {
302 302 return (0);
303 303 }
304 304
305 305 /*
306 306 * Common access routine. Disallow writes.
307 307 */
308 308 /* ARGSUSED */
309 309 static int
310 310 zfsctl_common_access(vnode_t *vp, int mode, int flags, cred_t *cr,
311 311 caller_context_t *ct)
312 312 {
313 313 if (flags & V_ACE_MASK) {
314 314 if (mode & ACE_ALL_WRITE_PERMS)
315 315 return (SET_ERROR(EACCES));
316 316 } else {
317 317 if (mode & VWRITE)
318 318 return (SET_ERROR(EACCES));
319 319 }
320 320
321 321 return (0);
322 322 }
323 323
324 324 /*
325 325 * Common getattr function. Fill in basic information.
326 326 */
327 327 static void
328 328 zfsctl_common_getattr(vnode_t *vp, vattr_t *vap)
329 329 {
330 330 timestruc_t now;
331 331
332 332 vap->va_uid = 0;
333 333 vap->va_gid = 0;
334 334 vap->va_rdev = 0;
335 335 /*
336 336 * We are a purely virtual object, so we have no
337 337 * blocksize or allocated blocks.
338 338 */
339 339 vap->va_blksize = 0;
340 340 vap->va_nblocks = 0;
341 341 vap->va_seq = 0;
342 342 vap->va_fsid = vp->v_vfsp->vfs_dev;
343 343 vap->va_mode = S_IRUSR | S_IXUSR | S_IRGRP | S_IXGRP |
344 344 S_IROTH | S_IXOTH;
345 345 vap->va_type = VDIR;
346 346 /*
347 347 * We live in the now (for atime).
348 348 */
349 349 gethrestime(&now);
350 350 vap->va_atime = now;
351 351 }
352 352
353 353 /*ARGSUSED*/
354 354 static int
355 355 zfsctl_common_fid(vnode_t *vp, fid_t *fidp, caller_context_t *ct)
356 356 {
357 357 zfsvfs_t *zfsvfs = vp->v_vfsp->vfs_data;
358 358 zfsctl_node_t *zcp = vp->v_data;
359 359 uint64_t object = zcp->zc_id;
360 360 zfid_short_t *zfid;
361 361 int i;
362 362
363 363 ZFS_ENTER(zfsvfs);
364 364
365 365 if (fidp->fid_len < SHORT_FID_LEN) {
366 366 fidp->fid_len = SHORT_FID_LEN;
367 367 ZFS_EXIT(zfsvfs);
368 368 return (SET_ERROR(ENOSPC));
369 369 }
370 370
371 371 zfid = (zfid_short_t *)fidp;
372 372
373 373 zfid->zf_len = SHORT_FID_LEN;
374 374
375 375 for (i = 0; i < sizeof (zfid->zf_object); i++)
376 376 zfid->zf_object[i] = (uint8_t)(object >> (8 * i));
377 377
378 378 /* .zfs znodes always have a generation number of 0 */
379 379 for (i = 0; i < sizeof (zfid->zf_gen); i++)
380 380 zfid->zf_gen[i] = 0;
381 381
382 382 ZFS_EXIT(zfsvfs);
383 383 return (0);
384 384 }
385 385
386 386
387 387 /*ARGSUSED*/
388 388 static int
389 389 zfsctl_shares_fid(vnode_t *vp, fid_t *fidp, caller_context_t *ct)
390 390 {
391 391 zfsvfs_t *zfsvfs = vp->v_vfsp->vfs_data;
392 392 znode_t *dzp;
393 393 int error;
394 394
395 395 ZFS_ENTER(zfsvfs);
396 396
397 397 if (zfsvfs->z_shares_dir == 0) {
398 398 ZFS_EXIT(zfsvfs);
399 399 return (SET_ERROR(ENOTSUP));
400 400 }
401 401
402 402 if ((error = zfs_zget(zfsvfs, zfsvfs->z_shares_dir, &dzp)) == 0) {
403 403 error = VOP_FID(ZTOV(dzp), fidp, ct);
404 404 VN_RELE(ZTOV(dzp));
405 405 }
406 406
407 407 ZFS_EXIT(zfsvfs);
408 408 return (error);
409 409 }
410 410 /*
411 411 * .zfs inode namespace
412 412 *
413 413 * We need to generate unique inode numbers for all files and directories
414 414 * within the .zfs pseudo-filesystem. We use the following scheme:
415 415 *
416 416 * ENTRY ZFSCTL_INODE
417 417 * .zfs 1
418 418 * .zfs/snapshot 2
419 419 * .zfs/snapshot/<snap> objectid(snap)
420 420 */
421 421
422 422 #define ZFSCTL_INO_SNAP(id) (id)
423 423
424 424 /*
425 425 * Get root directory attributes.
426 426 */
427 427 /* ARGSUSED */
428 428 static int
429 429 zfsctl_root_getattr(vnode_t *vp, vattr_t *vap, int flags, cred_t *cr,
430 430 caller_context_t *ct)
431 431 {
432 432 zfsvfs_t *zfsvfs = vp->v_vfsp->vfs_data;
433 433 zfsctl_node_t *zcp = vp->v_data;
434 434
435 435 ZFS_ENTER(zfsvfs);
436 436 vap->va_nodeid = ZFSCTL_INO_ROOT;
437 437 vap->va_nlink = vap->va_size = NROOT_ENTRIES;
438 438 vap->va_mtime = vap->va_ctime = zcp->zc_cmtime;
439 439
440 440 zfsctl_common_getattr(vp, vap);
441 441 ZFS_EXIT(zfsvfs);
442 442
443 443 return (0);
444 444 }
445 445
446 446 /*
447 447 * Special case the handling of "..".
448 448 */
449 449 /* ARGSUSED */
450 450 int
451 451 zfsctl_root_lookup(vnode_t *dvp, char *nm, vnode_t **vpp, pathname_t *pnp,
452 452 int flags, vnode_t *rdir, cred_t *cr, caller_context_t *ct,
453 453 int *direntflags, pathname_t *realpnp)
454 454 {
455 455 zfsvfs_t *zfsvfs = dvp->v_vfsp->vfs_data;
456 456 int err;
457 457
458 458 /*
459 459 * No extended attributes allowed under .zfs
460 460 */
461 461 if (flags & LOOKUP_XATTR)
462 462 return (SET_ERROR(EINVAL));
463 463
464 464 ZFS_ENTER(zfsvfs);
465 465
466 466 if (strcmp(nm, "..") == 0) {
467 467 err = VFS_ROOT(dvp->v_vfsp, vpp);
468 468 } else {
469 469 err = gfs_vop_lookup(dvp, nm, vpp, pnp, flags, rdir,
470 470 cr, ct, direntflags, realpnp);
471 471 }
472 472
473 473 ZFS_EXIT(zfsvfs);
474 474
475 475 return (err);
476 476 }
477 477
478 478 static int
479 479 zfsctl_pathconf(vnode_t *vp, int cmd, ulong_t *valp, cred_t *cr,
480 480 caller_context_t *ct)
481 481 {
482 482 /*
483 483 * We only care about ACL_ENABLED so that libsec can
484 484 * display ACL correctly and not default to POSIX draft.
485 485 */
486 486 if (cmd == _PC_ACL_ENABLED) {
487 487 *valp = _ACL_ACE_ENABLED;
488 488 return (0);
489 489 }
490 490
491 491 return (fs_pathconf(vp, cmd, valp, cr, ct));
492 492 }
493 493
494 494 static const fs_operation_def_t zfsctl_tops_root[] = {
495 495 { VOPNAME_OPEN, { .vop_open = zfsctl_common_open } },
496 496 { VOPNAME_CLOSE, { .vop_close = zfsctl_common_close } },
497 497 { VOPNAME_IOCTL, { .error = fs_inval } },
498 498 { VOPNAME_GETATTR, { .vop_getattr = zfsctl_root_getattr } },
499 499 { VOPNAME_ACCESS, { .vop_access = zfsctl_common_access } },
500 500 { VOPNAME_READDIR, { .vop_readdir = gfs_vop_readdir } },
501 501 { VOPNAME_LOOKUP, { .vop_lookup = zfsctl_root_lookup } },
502 502 { VOPNAME_SEEK, { .vop_seek = fs_seek } },
503 503 { VOPNAME_INACTIVE, { .vop_inactive = gfs_vop_inactive } },
504 504 { VOPNAME_PATHCONF, { .vop_pathconf = zfsctl_pathconf } },
505 505 { VOPNAME_FID, { .vop_fid = zfsctl_common_fid } },
506 506 { NULL }
507 507 };
508 508
509 509 /*
510 510 * Gets the full dataset name that corresponds to the given snapshot name
511 511 * Example:
512 512 * zfsctl_snapshot_zname("snap1") -> "mypool/myfs@snap1"
513 513 */
514 514 static int
515 515 zfsctl_snapshot_zname(vnode_t *vp, const char *name, int len, char *zname)
516 516 {
517 517 objset_t *os = ((zfsvfs_t *)((vp)->v_vfsp->vfs_data))->z_os;
518 518
519 519 if (zfs_component_namecheck(name, NULL, NULL) != 0)
520 520 return (SET_ERROR(EILSEQ));
521 521 dmu_objset_name(os, zname);
522 522 if (strlen(zname) + 1 + strlen(name) >= len)
523 523 return (SET_ERROR(ENAMETOOLONG));
524 524 (void) strcat(zname, "@");
525 525 (void) strcat(zname, name);
526 526 return (0);
527 527 }
528 528
529 529 static int
530 530 zfsctl_unmount_snap(zfs_snapentry_t *sep, int fflags, cred_t *cr)
531 531 {
532 532 vnode_t *svp = sep->se_root;
533 533 int error;
534 534
535 535 ASSERT(vn_ismntpt(svp));
536 536
537 537 /* this will be dropped by dounmount() */
538 538 if ((error = vn_vfswlock(svp)) != 0)
539 539 return (error);
540 540
541 541 VN_HOLD(svp);
542 542 error = dounmount(vn_mountedvfs(svp), fflags, cr);
543 543 if (error) {
544 544 VN_RELE(svp);
545 545 return (error);
546 546 }
547 547
548 548 /*
549 549 * We can't use VN_RELE(), as that will try to invoke
550 550 * zfsctl_snapdir_inactive(), which would cause us to destroy
551 551 * the sd_lock mutex held by our caller.
552 552 */
553 553 ASSERT(svp->v_count == 1);
554 554 gfs_vop_inactive(svp, cr, NULL);
555 555
556 556 kmem_free(sep->se_name, strlen(sep->se_name) + 1);
557 557 kmem_free(sep, sizeof (zfs_snapentry_t));
558 558
559 559 return (0);
560 560 }
561 561
562 562 static void
563 563 zfsctl_rename_snap(zfsctl_snapdir_t *sdp, zfs_snapentry_t *sep, const char *nm)
564 564 {
565 565 avl_index_t where;
566 566 vfs_t *vfsp;
567 567 refstr_t *pathref;
568 568 char newpath[MAXNAMELEN];
569 569 char *tail;
570 570
571 571 ASSERT(MUTEX_HELD(&sdp->sd_lock));
572 572 ASSERT(sep != NULL);
573 573
574 574 vfsp = vn_mountedvfs(sep->se_root);
575 575 ASSERT(vfsp != NULL);
576 576
577 577 vfs_lock_wait(vfsp);
578 578
579 579 /*
580 580 * Change the name in the AVL tree.
581 581 */
582 582 avl_remove(&sdp->sd_snaps, sep);
583 583 kmem_free(sep->se_name, strlen(sep->se_name) + 1);
584 584 sep->se_name = kmem_alloc(strlen(nm) + 1, KM_SLEEP);
585 585 (void) strcpy(sep->se_name, nm);
586 586 VERIFY(avl_find(&sdp->sd_snaps, sep, &where) == NULL);
587 587 avl_insert(&sdp->sd_snaps, sep, where);
588 588
589 589 /*
590 590 * Change the current mountpoint info:
591 591 * - update the tail of the mntpoint path
592 592 * - update the tail of the resource path
593 593 */
594 594 pathref = vfs_getmntpoint(vfsp);
595 595 (void) strncpy(newpath, refstr_value(pathref), sizeof (newpath));
596 596 VERIFY((tail = strrchr(newpath, '/')) != NULL);
597 597 *(tail+1) = '\0';
598 598 ASSERT3U(strlen(newpath) + strlen(nm), <, sizeof (newpath));
599 599 (void) strcat(newpath, nm);
600 600 refstr_rele(pathref);
601 601 vfs_setmntpoint(vfsp, newpath, 0);
602 602
603 603 pathref = vfs_getresource(vfsp);
604 604 (void) strncpy(newpath, refstr_value(pathref), sizeof (newpath));
605 605 VERIFY((tail = strrchr(newpath, '@')) != NULL);
606 606 *(tail+1) = '\0';
607 607 ASSERT3U(strlen(newpath) + strlen(nm), <, sizeof (newpath));
608 608 (void) strcat(newpath, nm);
609 609 refstr_rele(pathref);
610 610 vfs_setresource(vfsp, newpath, 0);
611 611
612 612 vfs_unlock(vfsp);
613 613 }
614 614
615 615 /*ARGSUSED*/
616 616 static int
617 617 zfsctl_snapdir_rename(vnode_t *sdvp, char *snm, vnode_t *tdvp, char *tnm,
618 618 cred_t *cr, caller_context_t *ct, int flags)
619 619 {
620 620 zfsctl_snapdir_t *sdp = sdvp->v_data;
621 621 zfs_snapentry_t search, *sep;
622 622 zfsvfs_t *zfsvfs;
623 623 avl_index_t where;
624 624 char from[ZFS_MAX_DATASET_NAME_LEN], to[ZFS_MAX_DATASET_NAME_LEN];
625 625 char real[ZFS_MAX_DATASET_NAME_LEN], fsname[ZFS_MAX_DATASET_NAME_LEN];
626 626 int err;
627 627
628 628 zfsvfs = sdvp->v_vfsp->vfs_data;
629 629 ZFS_ENTER(zfsvfs);
630 630
631 631 if ((flags & FIGNORECASE) || zfsvfs->z_case == ZFS_CASE_INSENSITIVE) {
632 632 err = dmu_snapshot_realname(zfsvfs->z_os, snm, real,
633 633 sizeof (real), NULL);
634 634 if (err == 0) {
635 635 snm = real;
636 636 } else if (err != ENOTSUP) {
637 637 ZFS_EXIT(zfsvfs);
638 638 return (err);
639 639 }
640 640 }
641 641
642 642 ZFS_EXIT(zfsvfs);
643 643
644 644 dmu_objset_name(zfsvfs->z_os, fsname);
645 645
646 646 err = zfsctl_snapshot_zname(sdvp, snm, sizeof (from), from);
647 647 if (err == 0)
648 648 err = zfsctl_snapshot_zname(tdvp, tnm, sizeof (to), to);
649 649 if (err == 0)
650 650 err = zfs_secpolicy_rename_perms(from, to, cr);
651 651 if (err != 0)
652 652 return (err);
653 653
654 654 /*
655 655 * Cannot move snapshots out of the snapdir.
656 656 */
657 657 if (sdvp != tdvp)
658 658 return (SET_ERROR(EINVAL));
659 659
660 660 if (strcmp(snm, tnm) == 0)
661 661 return (0);
662 662
663 663 mutex_enter(&sdp->sd_lock);
664 664
665 665 search.se_name = (char *)snm;
666 666 if ((sep = avl_find(&sdp->sd_snaps, &search, &where)) == NULL) {
667 667 mutex_exit(&sdp->sd_lock);
668 668 return (SET_ERROR(ENOENT));
669 669 }
670 670
671 671 err = dsl_dataset_rename_snapshot(fsname, snm, tnm, B_FALSE);
672 672 if (err == 0)
673 673 zfsctl_rename_snap(sdp, sep, tnm);
674 674
675 675 mutex_exit(&sdp->sd_lock);
676 676
677 677 return (err);
678 678 }
679 679
680 680 /* ARGSUSED */
681 681 static int
682 682 zfsctl_snapdir_remove(vnode_t *dvp, char *name, vnode_t *cwd, cred_t *cr,
683 683 caller_context_t *ct, int flags)
684 684 {
685 685 zfsctl_snapdir_t *sdp = dvp->v_data;
686 686 zfs_snapentry_t *sep;
687 687 zfs_snapentry_t search;
688 688 zfsvfs_t *zfsvfs;
689 689 char snapname[ZFS_MAX_DATASET_NAME_LEN];
690 690 char real[ZFS_MAX_DATASET_NAME_LEN];
691 691 int err;
692 692
693 693 zfsvfs = dvp->v_vfsp->vfs_data;
694 694 ZFS_ENTER(zfsvfs);
695 695
696 696 if ((flags & FIGNORECASE) || zfsvfs->z_case == ZFS_CASE_INSENSITIVE) {
697 697
698 698 err = dmu_snapshot_realname(zfsvfs->z_os, name, real,
699 699 sizeof (real), NULL);
700 700 if (err == 0) {
701 701 name = real;
702 702 } else if (err != ENOTSUP) {
703 703 ZFS_EXIT(zfsvfs);
704 704 return (err);
705 705 }
706 706 }
707 707
708 708 ZFS_EXIT(zfsvfs);
709 709
710 710 err = zfsctl_snapshot_zname(dvp, name, sizeof (snapname), snapname);
711 711 if (err == 0)
712 712 err = zfs_secpolicy_destroy_perms(snapname, cr);
713 713 if (err != 0)
714 714 return (err);
715 715
716 716 mutex_enter(&sdp->sd_lock);
717 717
718 718 search.se_name = name;
719 719 sep = avl_find(&sdp->sd_snaps, &search, NULL);
720 720 if (sep) {
721 721 avl_remove(&sdp->sd_snaps, sep);
722 722 err = zfsctl_unmount_snap(sep, MS_FORCE, cr);
723 723 if (err != 0)
724 724 avl_add(&sdp->sd_snaps, sep);
725 725 else
726 726 err = dsl_destroy_snapshot(snapname, B_FALSE);
727 727 } else {
728 728 err = SET_ERROR(ENOENT);
729 729 }
730 730
731 731 mutex_exit(&sdp->sd_lock);
732 732
733 733 return (err);
734 734 }
735 735
736 736 /*
737 737 * This creates a snapshot under '.zfs/snapshot'.
738 738 */
739 739 /* ARGSUSED */
740 740 static int
741 741 zfsctl_snapdir_mkdir(vnode_t *dvp, char *dirname, vattr_t *vap, vnode_t **vpp,
742 742 cred_t *cr, caller_context_t *cc, int flags, vsecattr_t *vsecp)
743 743 {
744 744 zfsvfs_t *zfsvfs = dvp->v_vfsp->vfs_data;
745 745 char name[ZFS_MAX_DATASET_NAME_LEN];
746 746 int err;
747 747 static enum symfollow follow = NO_FOLLOW;
748 748 static enum uio_seg seg = UIO_SYSSPACE;
749 749
750 750 if (zfs_component_namecheck(dirname, NULL, NULL) != 0)
751 751 return (SET_ERROR(EILSEQ));
752 752
753 753 dmu_objset_name(zfsvfs->z_os, name);
754 754
755 755 *vpp = NULL;
756 756
757 757 err = zfs_secpolicy_snapshot_perms(name, cr);
758 758 if (err != 0)
759 759 return (err);
760 760
761 761 if (err == 0) {
762 762 err = dmu_objset_snapshot_one(name, dirname);
763 763 if (err != 0)
764 764 return (err);
765 765 err = lookupnameat(dirname, seg, follow, NULL, vpp, dvp);
766 766 }
767 767
768 768 return (err);
769 769 }
770 770
771 771 /*
772 772 * Lookup entry point for the 'snapshot' directory. Try to open the
773 773 * snapshot if it exist, creating the pseudo filesystem vnode as necessary.
774 774 * Perform a mount of the associated dataset on top of the vnode.
775 775 */
776 776 /* ARGSUSED */
777 777 static int
778 778 zfsctl_snapdir_lookup(vnode_t *dvp, char *nm, vnode_t **vpp, pathname_t *pnp,
779 779 int flags, vnode_t *rdir, cred_t *cr, caller_context_t *ct,
780 780 int *direntflags, pathname_t *realpnp)
781 781 {
782 782 zfsctl_snapdir_t *sdp = dvp->v_data;
783 783 objset_t *snap;
784 784 char snapname[ZFS_MAX_DATASET_NAME_LEN];
785 785 char real[ZFS_MAX_DATASET_NAME_LEN];
786 786 char *mountpoint;
787 787 zfs_snapentry_t *sep, search;
788 788 struct mounta margs;
789 789 vfs_t *vfsp;
790 790 size_t mountpoint_len;
791 791 avl_index_t where;
792 792 zfsvfs_t *zfsvfs = dvp->v_vfsp->vfs_data;
793 793 int err;
794 794
795 795 /*
796 796 * No extended attributes allowed under .zfs
797 797 */
798 798 if (flags & LOOKUP_XATTR)
799 799 return (SET_ERROR(EINVAL));
800 800
801 801 ASSERT(dvp->v_type == VDIR);
802 802
803 803 /*
804 804 * If we get a recursive call, that means we got called
805 805 * from the domount() code while it was trying to look up the
806 806 * spec (which looks like a local path for zfs). We need to
807 807 * add some flag to domount() to tell it not to do this lookup.
808 808 */
809 809 if (MUTEX_HELD(&sdp->sd_lock))
810 810 return (SET_ERROR(ENOENT));
811 811
812 812 ZFS_ENTER(zfsvfs);
813 813
814 814 if (gfs_lookup_dot(vpp, dvp, zfsvfs->z_ctldir, nm) == 0) {
815 815 ZFS_EXIT(zfsvfs);
816 816 return (0);
817 817 }
818 818
819 819 if (flags & FIGNORECASE) {
820 820 boolean_t conflict = B_FALSE;
821 821
822 822 err = dmu_snapshot_realname(zfsvfs->z_os, nm, real,
823 823 sizeof (real), &conflict);
824 824 if (err == 0) {
825 825 nm = real;
826 826 } else if (err != ENOTSUP) {
827 827 ZFS_EXIT(zfsvfs);
828 828 return (err);
829 829 }
830 830 if (realpnp)
831 831 (void) strlcpy(realpnp->pn_buf, nm,
832 832 realpnp->pn_bufsize);
833 833 if (conflict && direntflags)
834 834 *direntflags = ED_CASE_CONFLICT;
835 835 }
836 836
837 837 mutex_enter(&sdp->sd_lock);
838 838 search.se_name = (char *)nm;
839 839 if ((sep = avl_find(&sdp->sd_snaps, &search, &where)) != NULL) {
840 840 *vpp = sep->se_root;
841 841 VN_HOLD(*vpp);
842 842 err = traverse(vpp);
843 843 if (err != 0) {
844 844 VN_RELE(*vpp);
845 845 *vpp = NULL;
846 846 } else if (*vpp == sep->se_root) {
847 847 /*
848 848 * The snapshot was unmounted behind our backs,
849 849 * try to remount it.
850 850 */
851 851 goto domount;
852 852 } else {
853 853 /*
854 854 * VROOT was set during the traverse call. We need
855 855 * to clear it since we're pretending to be part
856 856 * of our parent's vfs.
857 857 */
858 858 (*vpp)->v_flag &= ~VROOT;
859 859 }
860 860 mutex_exit(&sdp->sd_lock);
861 861 ZFS_EXIT(zfsvfs);
862 862 return (err);
863 863 }
864 864
865 865 /*
866 866 * The requested snapshot is not currently mounted, look it up.
867 867 */
868 868 err = zfsctl_snapshot_zname(dvp, nm, sizeof (snapname), snapname);
869 869 if (err != 0) {
870 870 mutex_exit(&sdp->sd_lock);
871 871 ZFS_EXIT(zfsvfs);
872 872 /*
873 873 * handle "ls *" or "?" in a graceful manner,
874 874 * forcing EILSEQ to ENOENT.
875 875 * Since shell ultimately passes "*" or "?" as name to lookup
876 876 */
877 877 return (err == EILSEQ ? ENOENT : err);
878 878 }
879 879 if (dmu_objset_hold(snapname, FTAG, &snap) != 0) {
880 880 mutex_exit(&sdp->sd_lock);
881 881 ZFS_EXIT(zfsvfs);
882 882 return (SET_ERROR(ENOENT));
883 883 }
884 884
885 885 sep = kmem_alloc(sizeof (zfs_snapentry_t), KM_SLEEP);
886 886 sep->se_name = kmem_alloc(strlen(nm) + 1, KM_SLEEP);
887 887 (void) strcpy(sep->se_name, nm);
888 888 *vpp = sep->se_root = zfsctl_snapshot_mknode(dvp, dmu_objset_id(snap));
889 889 avl_insert(&sdp->sd_snaps, sep, where);
890 890
891 891 dmu_objset_rele(snap, FTAG);
892 892 domount:
893 893 mountpoint_len = strlen(refstr_value(dvp->v_vfsp->vfs_mntpt)) +
894 894 strlen("/.zfs/snapshot/") + strlen(nm) + 1;
895 895 mountpoint = kmem_alloc(mountpoint_len, KM_SLEEP);
896 896 (void) snprintf(mountpoint, mountpoint_len, "%s/.zfs/snapshot/%s",
897 897 refstr_value(dvp->v_vfsp->vfs_mntpt), nm);
898 898
899 899 margs.spec = snapname;
900 900 margs.dir = mountpoint;
901 901 margs.flags = MS_SYSSPACE | MS_NOMNTTAB;
902 902 margs.fstype = "zfs";
903 903 margs.dataptr = NULL;
904 904 margs.datalen = 0;
905 905 margs.optptr = NULL;
906 906 margs.optlen = 0;
907 907
908 908 err = domount("zfs", &margs, *vpp, kcred, &vfsp);
909 909 kmem_free(mountpoint, mountpoint_len);
910 910
911 911 if (err == 0) {
912 912 /*
913 913 * Return the mounted root rather than the covered mount point.
914 914 * Takes the GFS vnode at .zfs/snapshot/<snapname> and returns
915 915 * the ZFS vnode mounted on top of the GFS node. This ZFS
916 916 * vnode is the root of the newly created vfsp.
917 917 */
918 918 VFS_RELE(vfsp);
919 919 err = traverse(vpp);
920 920 }
921 921
922 922 if (err == 0) {
923 923 /*
924 924 * Fix up the root vnode mounted on .zfs/snapshot/<snapname>.
925 925 *
926 926 * This is where we lie about our v_vfsp in order to
927 927 * make .zfs/snapshot/<snapname> accessible over NFS
928 928 * without requiring manual mounts of <snapname>.
929 929 */
930 930 ASSERT(VTOZ(*vpp)->z_zfsvfs != zfsvfs);
931 931 VTOZ(*vpp)->z_zfsvfs->z_parent = zfsvfs;
932 932 (*vpp)->v_vfsp = zfsvfs->z_vfs;
933 933 (*vpp)->v_flag &= ~VROOT;
934 934 }
935 935 mutex_exit(&sdp->sd_lock);
936 936 ZFS_EXIT(zfsvfs);
937 937
938 938 /*
939 939 * If we had an error, drop our hold on the vnode and
940 940 * zfsctl_snapshot_inactive() will clean up.
941 941 */
942 942 if (err != 0) {
943 943 VN_RELE(*vpp);
944 944 *vpp = NULL;
945 945 }
946 946 return (err);
947 947 }
948 948
949 949 /* ARGSUSED */
950 950 static int
951 951 zfsctl_shares_lookup(vnode_t *dvp, char *nm, vnode_t **vpp, pathname_t *pnp,
952 952 int flags, vnode_t *rdir, cred_t *cr, caller_context_t *ct,
953 953 int *direntflags, pathname_t *realpnp)
954 954 {
955 955 zfsvfs_t *zfsvfs = dvp->v_vfsp->vfs_data;
956 956 znode_t *dzp;
957 957 int error;
958 958
959 959 ZFS_ENTER(zfsvfs);
960 960
961 961 if (gfs_lookup_dot(vpp, dvp, zfsvfs->z_ctldir, nm) == 0) {
962 962 ZFS_EXIT(zfsvfs);
963 963 return (0);
964 964 }
965 965
966 966 if (zfsvfs->z_shares_dir == 0) {
967 967 ZFS_EXIT(zfsvfs);
968 968 return (SET_ERROR(ENOTSUP));
969 969 }
970 970 if ((error = zfs_zget(zfsvfs, zfsvfs->z_shares_dir, &dzp)) == 0) {
971 971 error = VOP_LOOKUP(ZTOV(dzp), nm, vpp, pnp,
972 972 flags, rdir, cr, ct, direntflags, realpnp);
973 973 VN_RELE(ZTOV(dzp));
974 974 }
975 975
976 976 ZFS_EXIT(zfsvfs);
977 977
978 978 return (error);
979 979 }
980 980
981 981 /* ARGSUSED */
982 982 static int
983 983 zfsctl_snapdir_readdir_cb(vnode_t *vp, void *dp, int *eofp,
984 984 offset_t *offp, offset_t *nextp, void *data, int flags)
985 985 {
986 986 zfsvfs_t *zfsvfs = vp->v_vfsp->vfs_data;
987 987 char snapname[ZFS_MAX_DATASET_NAME_LEN];
988 988 uint64_t id, cookie;
989 989 boolean_t case_conflict;
990 990 int error;
991 991
992 992 ZFS_ENTER(zfsvfs);
993 993
994 994 cookie = *offp;
995 995 dsl_pool_config_enter(dmu_objset_pool(zfsvfs->z_os), FTAG);
996 996 error = dmu_snapshot_list_next(zfsvfs->z_os,
997 997 sizeof (snapname), snapname, &id, &cookie, &case_conflict);
998 998 dsl_pool_config_exit(dmu_objset_pool(zfsvfs->z_os), FTAG);
999 999 if (error) {
1000 1000 ZFS_EXIT(zfsvfs);
1001 1001 if (error == ENOENT) {
1002 1002 *eofp = 1;
1003 1003 return (0);
1004 1004 }
1005 1005 return (error);
1006 1006 }
1007 1007
1008 1008 if (flags & V_RDDIR_ENTFLAGS) {
1009 1009 edirent_t *eodp = dp;
1010 1010
1011 1011 (void) strcpy(eodp->ed_name, snapname);
1012 1012 eodp->ed_ino = ZFSCTL_INO_SNAP(id);
1013 1013 eodp->ed_eflags = case_conflict ? ED_CASE_CONFLICT : 0;
1014 1014 } else {
1015 1015 struct dirent64 *odp = dp;
1016 1016
1017 1017 (void) strcpy(odp->d_name, snapname);
1018 1018 odp->d_ino = ZFSCTL_INO_SNAP(id);
1019 1019 }
1020 1020 *nextp = cookie;
1021 1021
1022 1022 ZFS_EXIT(zfsvfs);
1023 1023
1024 1024 return (0);
1025 1025 }
1026 1026
1027 1027 /* ARGSUSED */
1028 1028 static int
1029 1029 zfsctl_shares_readdir(vnode_t *vp, uio_t *uiop, cred_t *cr, int *eofp,
1030 1030 caller_context_t *ct, int flags)
1031 1031 {
1032 1032 zfsvfs_t *zfsvfs = vp->v_vfsp->vfs_data;
1033 1033 znode_t *dzp;
1034 1034 int error;
1035 1035
1036 1036 ZFS_ENTER(zfsvfs);
1037 1037
1038 1038 if (zfsvfs->z_shares_dir == 0) {
1039 1039 ZFS_EXIT(zfsvfs);
1040 1040 return (SET_ERROR(ENOTSUP));
1041 1041 }
1042 1042 if ((error = zfs_zget(zfsvfs, zfsvfs->z_shares_dir, &dzp)) == 0) {
1043 1043 error = VOP_READDIR(ZTOV(dzp), uiop, cr, eofp, ct, flags);
1044 1044 VN_RELE(ZTOV(dzp));
1045 1045 } else {
1046 1046 *eofp = 1;
1047 1047 error = SET_ERROR(ENOENT);
1048 1048 }
1049 1049
1050 1050 ZFS_EXIT(zfsvfs);
1051 1051 return (error);
1052 1052 }
1053 1053
1054 1054 /*
1055 1055 * pvp is the '.zfs' directory (zfsctl_node_t).
1056 1056 *
1057 1057 * Creates vp, which is '.zfs/snapshot' (zfsctl_snapdir_t).
1058 1058 *
1059 1059 * This function is the callback to create a GFS vnode for '.zfs/snapshot'
1060 1060 * when a lookup is performed on .zfs for "snapshot".
1061 1061 */
1062 1062 vnode_t *
1063 1063 zfsctl_mknode_snapdir(vnode_t *pvp)
1064 1064 {
1065 1065 vnode_t *vp;
1066 1066 zfsctl_snapdir_t *sdp;
1067 1067
1068 1068 vp = gfs_dir_create(sizeof (zfsctl_snapdir_t), pvp,
1069 1069 zfsctl_ops_snapdir, NULL, NULL, MAXNAMELEN,
1070 1070 zfsctl_snapdir_readdir_cb, NULL);
1071 1071 sdp = vp->v_data;
1072 1072 sdp->sd_node.zc_id = ZFSCTL_INO_SNAPDIR;
1073 1073 sdp->sd_node.zc_cmtime = ((zfsctl_node_t *)pvp->v_data)->zc_cmtime;
1074 1074 mutex_init(&sdp->sd_lock, NULL, MUTEX_DEFAULT, NULL);
1075 1075 avl_create(&sdp->sd_snaps, snapentry_compare,
1076 1076 sizeof (zfs_snapentry_t), offsetof(zfs_snapentry_t, se_node));
1077 1077 return (vp);
1078 1078 }
1079 1079
1080 1080 vnode_t *
1081 1081 zfsctl_mknode_shares(vnode_t *pvp)
1082 1082 {
1083 1083 vnode_t *vp;
1084 1084 zfsctl_node_t *sdp;
1085 1085
1086 1086 vp = gfs_dir_create(sizeof (zfsctl_node_t), pvp,
1087 1087 zfsctl_ops_shares, NULL, NULL, MAXNAMELEN,
1088 1088 NULL, NULL);
1089 1089 sdp = vp->v_data;
1090 1090 sdp->zc_cmtime = ((zfsctl_node_t *)pvp->v_data)->zc_cmtime;
1091 1091 return (vp);
1092 1092
1093 1093 }
1094 1094
1095 1095 /* ARGSUSED */
1096 1096 static int
1097 1097 zfsctl_shares_getattr(vnode_t *vp, vattr_t *vap, int flags, cred_t *cr,
1098 1098 caller_context_t *ct)
1099 1099 {
1100 1100 zfsvfs_t *zfsvfs = vp->v_vfsp->vfs_data;
1101 1101 znode_t *dzp;
1102 1102 int error;
1103 1103
1104 1104 ZFS_ENTER(zfsvfs);
1105 1105 if (zfsvfs->z_shares_dir == 0) {
1106 1106 ZFS_EXIT(zfsvfs);
1107 1107 return (SET_ERROR(ENOTSUP));
1108 1108 }
1109 1109 if ((error = zfs_zget(zfsvfs, zfsvfs->z_shares_dir, &dzp)) == 0) {
1110 1110 error = VOP_GETATTR(ZTOV(dzp), vap, flags, cr, ct);
1111 1111 VN_RELE(ZTOV(dzp));
1112 1112 }
1113 1113 ZFS_EXIT(zfsvfs);
1114 1114 return (error);
1115 1115
1116 1116
1117 1117 }
1118 1118
1119 1119 /* ARGSUSED */
1120 1120 static int
1121 1121 zfsctl_snapdir_getattr(vnode_t *vp, vattr_t *vap, int flags, cred_t *cr,
1122 1122 caller_context_t *ct)
1123 1123 {
1124 1124 zfsvfs_t *zfsvfs = vp->v_vfsp->vfs_data;
1125 1125 zfsctl_snapdir_t *sdp = vp->v_data;
1126 1126
1127 1127 ZFS_ENTER(zfsvfs);
1128 1128 zfsctl_common_getattr(vp, vap);
1129 1129 vap->va_nodeid = gfs_file_inode(vp);
1130 1130 vap->va_nlink = vap->va_size = avl_numnodes(&sdp->sd_snaps) + 2;
1131 1131 vap->va_ctime = vap->va_mtime = dmu_objset_snap_cmtime(zfsvfs->z_os);
1132 1132 ZFS_EXIT(zfsvfs);
1133 1133
1134 1134 return (0);
1135 1135 }
1136 1136
1137 1137 /* ARGSUSED */
1138 1138 static void
1139 1139 zfsctl_snapdir_inactive(vnode_t *vp, cred_t *cr, caller_context_t *ct)
1140 1140 {
1141 1141 zfsctl_snapdir_t *sdp = vp->v_data;
1142 1142 void *private;
1143 1143
1144 1144 private = gfs_dir_inactive(vp);
1145 1145 if (private != NULL) {
1146 1146 ASSERT(avl_numnodes(&sdp->sd_snaps) == 0);
1147 1147 mutex_destroy(&sdp->sd_lock);
1148 1148 avl_destroy(&sdp->sd_snaps);
1149 1149 kmem_free(private, sizeof (zfsctl_snapdir_t));
1150 1150 }
1151 1151 }
1152 1152
1153 1153 static const fs_operation_def_t zfsctl_tops_snapdir[] = {
1154 1154 { VOPNAME_OPEN, { .vop_open = zfsctl_common_open } },
1155 1155 { VOPNAME_CLOSE, { .vop_close = zfsctl_common_close } },
1156 1156 { VOPNAME_IOCTL, { .error = fs_inval } },
1157 1157 { VOPNAME_GETATTR, { .vop_getattr = zfsctl_snapdir_getattr } },
1158 1158 { VOPNAME_ACCESS, { .vop_access = zfsctl_common_access } },
1159 1159 { VOPNAME_RENAME, { .vop_rename = zfsctl_snapdir_rename } },
1160 1160 { VOPNAME_RMDIR, { .vop_rmdir = zfsctl_snapdir_remove } },
1161 1161 { VOPNAME_MKDIR, { .vop_mkdir = zfsctl_snapdir_mkdir } },
1162 1162 { VOPNAME_READDIR, { .vop_readdir = gfs_vop_readdir } },
1163 1163 { VOPNAME_LOOKUP, { .vop_lookup = zfsctl_snapdir_lookup } },
1164 1164 { VOPNAME_SEEK, { .vop_seek = fs_seek } },
1165 1165 { VOPNAME_INACTIVE, { .vop_inactive = zfsctl_snapdir_inactive } },
1166 1166 { VOPNAME_FID, { .vop_fid = zfsctl_common_fid } },
1167 1167 { NULL }
1168 1168 };
1169 1169
1170 1170 static const fs_operation_def_t zfsctl_tops_shares[] = {
1171 1171 { VOPNAME_OPEN, { .vop_open = zfsctl_common_open } },
1172 1172 { VOPNAME_CLOSE, { .vop_close = zfsctl_common_close } },
1173 1173 { VOPNAME_IOCTL, { .error = fs_inval } },
1174 1174 { VOPNAME_GETATTR, { .vop_getattr = zfsctl_shares_getattr } },
1175 1175 { VOPNAME_ACCESS, { .vop_access = zfsctl_common_access } },
1176 1176 { VOPNAME_READDIR, { .vop_readdir = zfsctl_shares_readdir } },
1177 1177 { VOPNAME_LOOKUP, { .vop_lookup = zfsctl_shares_lookup } },
1178 1178 { VOPNAME_SEEK, { .vop_seek = fs_seek } },
1179 1179 { VOPNAME_INACTIVE, { .vop_inactive = gfs_vop_inactive } },
1180 1180 { VOPNAME_FID, { .vop_fid = zfsctl_shares_fid } },
1181 1181 { NULL }
1182 1182 };
1183 1183
1184 1184 /*
1185 1185 * pvp is the GFS vnode '.zfs/snapshot'.
1186 1186 *
1187 1187 * This creates a GFS node under '.zfs/snapshot' representing each
1188 1188 * snapshot. This newly created GFS node is what we mount snapshot
1189 1189 * vfs_t's ontop of.
1190 1190 */
1191 1191 static vnode_t *
1192 1192 zfsctl_snapshot_mknode(vnode_t *pvp, uint64_t objset)
1193 1193 {
1194 1194 vnode_t *vp;
1195 1195 zfsctl_node_t *zcp;
1196 1196
1197 1197 vp = gfs_dir_create(sizeof (zfsctl_node_t), pvp,
1198 1198 zfsctl_ops_snapshot, NULL, NULL, MAXNAMELEN, NULL, NULL);
1199 1199 zcp = vp->v_data;
1200 1200 zcp->zc_id = objset;
1201 1201
1202 1202 return (vp);
1203 1203 }
1204 1204
1205 1205 static void
1206 1206 zfsctl_snapshot_inactive(vnode_t *vp, cred_t *cr, caller_context_t *ct)
1207 1207 {
1208 1208 zfsctl_snapdir_t *sdp;
1209 1209 zfs_snapentry_t *sep, *next;
1210 1210 vnode_t *dvp;
1211 1211
1212 1212 VERIFY(gfs_dir_lookup(vp, "..", &dvp, cr, 0, NULL, NULL) == 0);
1213 1213 sdp = dvp->v_data;
1214 1214
1215 1215 mutex_enter(&sdp->sd_lock);
1216 1216
1217 1217 mutex_enter(&vp->v_lock);
1218 1218 if (vp->v_count > 1) {
1219 1219 vp->v_count--;
1220 1220 mutex_exit(&vp->v_lock);
1221 1221 mutex_exit(&sdp->sd_lock);
1222 1222 VN_RELE(dvp);
1223 1223 return;
1224 1224 }
1225 1225 mutex_exit(&vp->v_lock);
1226 1226 ASSERT(!vn_ismntpt(vp));
1227 1227
1228 1228 sep = avl_first(&sdp->sd_snaps);
1229 1229 while (sep != NULL) {
1230 1230 next = AVL_NEXT(&sdp->sd_snaps, sep);
1231 1231
1232 1232 if (sep->se_root == vp) {
1233 1233 avl_remove(&sdp->sd_snaps, sep);
1234 1234 kmem_free(sep->se_name, strlen(sep->se_name) + 1);
1235 1235 kmem_free(sep, sizeof (zfs_snapentry_t));
1236 1236 break;
1237 1237 }
1238 1238 sep = next;
1239 1239 }
1240 1240 ASSERT(sep != NULL);
1241 1241
1242 1242 mutex_exit(&sdp->sd_lock);
1243 1243 VN_RELE(dvp);
1244 1244
1245 1245 /*
1246 1246 * Dispose of the vnode for the snapshot mount point.
1247 1247 * This is safe to do because once this entry has been removed
1248 1248 * from the AVL tree, it can't be found again, so cannot become
1249 1249 * "active". If we lookup the same name again we will end up
1250 1250 * creating a new vnode.
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1251 1251 */
1252 1252 gfs_vop_inactive(vp, cr, ct);
1253 1253 }
1254 1254
1255 1255
1256 1256 /*
1257 1257 * These VP's should never see the light of day. They should always
1258 1258 * be covered.
1259 1259 */
1260 1260 static const fs_operation_def_t zfsctl_tops_snapshot[] = {
1261 - VOPNAME_INACTIVE, { .vop_inactive = zfsctl_snapshot_inactive },
1262 - NULL, NULL
1261 + { VOPNAME_INACTIVE, { .vop_inactive = zfsctl_snapshot_inactive } },
1262 + { NULL, { NULL } }
1263 1263 };
1264 1264
1265 1265 int
1266 1266 zfsctl_lookup_objset(vfs_t *vfsp, uint64_t objsetid, zfsvfs_t **zfsvfsp)
1267 1267 {
1268 1268 zfsvfs_t *zfsvfs = vfsp->vfs_data;
1269 1269 vnode_t *dvp, *vp;
1270 1270 zfsctl_snapdir_t *sdp;
1271 1271 zfsctl_node_t *zcp;
1272 1272 zfs_snapentry_t *sep;
1273 1273 int error;
1274 1274
1275 1275 ASSERT(zfsvfs->z_ctldir != NULL);
1276 1276 error = zfsctl_root_lookup(zfsvfs->z_ctldir, "snapshot", &dvp,
1277 1277 NULL, 0, NULL, kcred, NULL, NULL, NULL);
1278 1278 if (error != 0)
1279 1279 return (error);
1280 1280 sdp = dvp->v_data;
1281 1281
1282 1282 mutex_enter(&sdp->sd_lock);
1283 1283 sep = avl_first(&sdp->sd_snaps);
1284 1284 while (sep != NULL) {
1285 1285 vp = sep->se_root;
1286 1286 zcp = vp->v_data;
1287 1287 if (zcp->zc_id == objsetid)
1288 1288 break;
1289 1289
1290 1290 sep = AVL_NEXT(&sdp->sd_snaps, sep);
1291 1291 }
1292 1292
1293 1293 if (sep != NULL) {
1294 1294 VN_HOLD(vp);
1295 1295 /*
1296 1296 * Return the mounted root rather than the covered mount point.
1297 1297 * Takes the GFS vnode at .zfs/snapshot/<snapshot objsetid>
1298 1298 * and returns the ZFS vnode mounted on top of the GFS node.
1299 1299 * This ZFS vnode is the root of the vfs for objset 'objsetid'.
1300 1300 */
1301 1301 error = traverse(&vp);
1302 1302 if (error == 0) {
1303 1303 if (vp == sep->se_root)
1304 1304 error = SET_ERROR(EINVAL);
1305 1305 else
1306 1306 *zfsvfsp = VTOZ(vp)->z_zfsvfs;
1307 1307 }
1308 1308 mutex_exit(&sdp->sd_lock);
1309 1309 VN_RELE(vp);
1310 1310 } else {
1311 1311 error = SET_ERROR(EINVAL);
1312 1312 mutex_exit(&sdp->sd_lock);
1313 1313 }
1314 1314
1315 1315 VN_RELE(dvp);
1316 1316
1317 1317 return (error);
1318 1318 }
1319 1319
1320 1320 /*
1321 1321 * Unmount any snapshots for the given filesystem. This is called from
1322 1322 * zfs_umount() - if we have a ctldir, then go through and unmount all the
1323 1323 * snapshots.
1324 1324 */
1325 1325 int
1326 1326 zfsctl_umount_snapshots(vfs_t *vfsp, int fflags, cred_t *cr)
1327 1327 {
1328 1328 zfsvfs_t *zfsvfs = vfsp->vfs_data;
1329 1329 vnode_t *dvp;
1330 1330 zfsctl_snapdir_t *sdp;
1331 1331 zfs_snapentry_t *sep, *next;
1332 1332 int error;
1333 1333
1334 1334 ASSERT(zfsvfs->z_ctldir != NULL);
1335 1335 error = zfsctl_root_lookup(zfsvfs->z_ctldir, "snapshot", &dvp,
1336 1336 NULL, 0, NULL, cr, NULL, NULL, NULL);
1337 1337 if (error != 0)
1338 1338 return (error);
1339 1339 sdp = dvp->v_data;
1340 1340
1341 1341 mutex_enter(&sdp->sd_lock);
1342 1342
1343 1343 sep = avl_first(&sdp->sd_snaps);
1344 1344 while (sep != NULL) {
1345 1345 next = AVL_NEXT(&sdp->sd_snaps, sep);
1346 1346
1347 1347 /*
1348 1348 * If this snapshot is not mounted, then it must
1349 1349 * have just been unmounted by somebody else, and
1350 1350 * will be cleaned up by zfsctl_snapdir_inactive().
1351 1351 */
1352 1352 if (vn_ismntpt(sep->se_root)) {
1353 1353 avl_remove(&sdp->sd_snaps, sep);
1354 1354 error = zfsctl_unmount_snap(sep, fflags, cr);
1355 1355 if (error) {
1356 1356 avl_add(&sdp->sd_snaps, sep);
1357 1357 break;
1358 1358 }
1359 1359 }
1360 1360 sep = next;
1361 1361 }
1362 1362
1363 1363 mutex_exit(&sdp->sd_lock);
1364 1364 VN_RELE(dvp);
1365 1365
1366 1366 return (error);
1367 1367 }
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