Print this page
3742 zfs comments need cleaner, more consistent style
Submitted by: Will Andrews <willa@spectralogic.com>
Submitted by: Alan Somers <alans@spectralogic.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Eric Schrock <eric.schrock@delphix.com>
Split |
Close |
Expand all |
Collapse all |
--- 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) 2013 by Delphix. All rights reserved.
24 24 */
25 25
26 26 /*
27 27 * ZFS control directory (a.k.a. ".zfs")
28 28 *
29 29 * This directory provides a common location for all ZFS meta-objects.
30 30 * Currently, this is only the 'snapshot' directory, but this may expand in the
31 31 * future. The elements are built using the GFS primitives, as the hierarchy
32 32 * does not actually exist on disk.
33 33 *
34 34 * For 'snapshot', we don't want to have all snapshots always mounted, because
35 35 * this would take up a huge amount of space in /etc/mnttab. We have three
36 36 * types of objects:
37 37 *
38 38 * ctldir ------> snapshotdir -------> snapshot
39 39 * |
40 40 * |
41 41 * V
42 42 * mounted fs
43 43 *
44 44 * The 'snapshot' node contains just enough information to lookup '..' and act
45 45 * as a mountpoint for the snapshot. Whenever we lookup a specific snapshot, we
46 46 * perform an automount of the underlying filesystem and return the
47 47 * corresponding vnode.
48 48 *
49 49 * All mounts are handled automatically by the kernel, but unmounts are
50 50 * (currently) handled from user land. The main reason is that there is no
51 51 * reliable way to auto-unmount the filesystem when it's "no longer in use".
52 52 * When the user unmounts a filesystem, we call zfsctl_unmount(), which
53 53 * unmounts any snapshots within the snapshot directory.
54 54 *
55 55 * The '.zfs', '.zfs/snapshot', and all directories created under
56 56 * '.zfs/snapshot' (ie: '.zfs/snapshot/<snapname>') are all GFS nodes and
57 57 * share the same vfs_t as the head filesystem (what '.zfs' lives under).
58 58 *
59 59 * File systems mounted ontop of the GFS nodes '.zfs/snapshot/<snapname>'
60 60 * (ie: snapshots) are ZFS nodes and have their own unique vfs_t.
61 61 * However, vnodes within these mounted on file systems have their v_vfsp
62 62 * fields set to the head filesystem to make NFS happy (see
63 63 * zfsctl_snapdir_lookup()). We VFS_HOLD the head filesystem's vfs_t
64 64 * so that it cannot be freed until all snapshots have been unmounted.
65 65 */
66 66
67 67 #include <fs/fs_subr.h>
68 68 #include <sys/zfs_ctldir.h>
69 69 #include <sys/zfs_ioctl.h>
70 70 #include <sys/zfs_vfsops.h>
71 71 #include <sys/vfs_opreg.h>
72 72 #include <sys/gfs.h>
73 73 #include <sys/stat.h>
74 74 #include <sys/dmu.h>
75 75 #include <sys/dsl_destroy.h>
76 76 #include <sys/dsl_deleg.h>
77 77 #include <sys/mount.h>
78 78 #include <sys/sunddi.h>
79 79
80 80 #include "zfs_namecheck.h"
81 81
82 82 typedef struct zfsctl_node {
83 83 gfs_dir_t zc_gfs_private;
84 84 uint64_t zc_id;
85 85 timestruc_t zc_cmtime; /* ctime and mtime, always the same */
86 86 } zfsctl_node_t;
87 87
88 88 typedef struct zfsctl_snapdir {
89 89 zfsctl_node_t sd_node;
90 90 kmutex_t sd_lock;
91 91 avl_tree_t sd_snaps;
92 92 } zfsctl_snapdir_t;
93 93
94 94 typedef struct {
95 95 char *se_name;
96 96 vnode_t *se_root;
97 97 avl_node_t se_node;
98 98 } zfs_snapentry_t;
99 99
100 100 static int
101 101 snapentry_compare(const void *a, const void *b)
102 102 {
103 103 const zfs_snapentry_t *sa = a;
104 104 const zfs_snapentry_t *sb = b;
105 105 int ret = strcmp(sa->se_name, sb->se_name);
106 106
107 107 if (ret < 0)
108 108 return (-1);
109 109 else if (ret > 0)
110 110 return (1);
111 111 else
112 112 return (0);
113 113 }
114 114
115 115 vnodeops_t *zfsctl_ops_root;
116 116 vnodeops_t *zfsctl_ops_snapdir;
117 117 vnodeops_t *zfsctl_ops_snapshot;
118 118 vnodeops_t *zfsctl_ops_shares;
119 119 vnodeops_t *zfsctl_ops_shares_dir;
120 120
121 121 static const fs_operation_def_t zfsctl_tops_root[];
122 122 static const fs_operation_def_t zfsctl_tops_snapdir[];
123 123 static const fs_operation_def_t zfsctl_tops_snapshot[];
124 124 static const fs_operation_def_t zfsctl_tops_shares[];
125 125
126 126 static vnode_t *zfsctl_mknode_snapdir(vnode_t *);
127 127 static vnode_t *zfsctl_mknode_shares(vnode_t *);
128 128 static vnode_t *zfsctl_snapshot_mknode(vnode_t *, uint64_t objset);
129 129 static int zfsctl_unmount_snap(zfs_snapentry_t *, int, cred_t *);
130 130
131 131 static gfs_opsvec_t zfsctl_opsvec[] = {
132 132 { ".zfs", zfsctl_tops_root, &zfsctl_ops_root },
133 133 { ".zfs/snapshot", zfsctl_tops_snapdir, &zfsctl_ops_snapdir },
134 134 { ".zfs/snapshot/vnode", zfsctl_tops_snapshot, &zfsctl_ops_snapshot },
135 135 { ".zfs/shares", zfsctl_tops_shares, &zfsctl_ops_shares_dir },
136 136 { ".zfs/shares/vnode", zfsctl_tops_shares, &zfsctl_ops_shares },
137 137 { NULL }
138 138 };
139 139
140 140 /*
141 141 * Root directory elements. We only have two entries
142 142 * snapshot and shares.
143 143 */
144 144 static gfs_dirent_t zfsctl_root_entries[] = {
145 145 { "snapshot", zfsctl_mknode_snapdir, GFS_CACHE_VNODE },
146 146 { "shares", zfsctl_mknode_shares, GFS_CACHE_VNODE },
147 147 { NULL }
148 148 };
149 149
150 150 /* include . and .. in the calculation */
151 151 #define NROOT_ENTRIES ((sizeof (zfsctl_root_entries) / \
152 152 sizeof (gfs_dirent_t)) + 1)
153 153
154 154
155 155 /*
156 156 * Initialize the various GFS pieces we'll need to create and manipulate .zfs
157 157 * directories. This is called from the ZFS init routine, and initializes the
158 158 * vnode ops vectors that we'll be using.
159 159 */
160 160 void
161 161 zfsctl_init(void)
162 162 {
163 163 VERIFY(gfs_make_opsvec(zfsctl_opsvec) == 0);
164 164 }
165 165
166 166 void
167 167 zfsctl_fini(void)
168 168 {
169 169 /*
170 170 * Remove vfsctl vnode ops
171 171 */
172 172 if (zfsctl_ops_root)
173 173 vn_freevnodeops(zfsctl_ops_root);
174 174 if (zfsctl_ops_snapdir)
175 175 vn_freevnodeops(zfsctl_ops_snapdir);
176 176 if (zfsctl_ops_snapshot)
177 177 vn_freevnodeops(zfsctl_ops_snapshot);
178 178 if (zfsctl_ops_shares)
179 179 vn_freevnodeops(zfsctl_ops_shares);
180 180 if (zfsctl_ops_shares_dir)
181 181 vn_freevnodeops(zfsctl_ops_shares_dir);
182 182
183 183 zfsctl_ops_root = NULL;
184 184 zfsctl_ops_snapdir = NULL;
185 185 zfsctl_ops_snapshot = NULL;
186 186 zfsctl_ops_shares = NULL;
187 187 zfsctl_ops_shares_dir = NULL;
188 188 }
189 189
190 190 boolean_t
191 191 zfsctl_is_node(vnode_t *vp)
192 192 {
193 193 return (vn_matchops(vp, zfsctl_ops_root) ||
194 194 vn_matchops(vp, zfsctl_ops_snapdir) ||
195 195 vn_matchops(vp, zfsctl_ops_snapshot) ||
196 196 vn_matchops(vp, zfsctl_ops_shares) ||
197 197 vn_matchops(vp, zfsctl_ops_shares_dir));
198 198
199 199 }
200 200
201 201 /*
202 202 * Return the inode number associated with the 'snapshot' or
203 203 * 'shares' directory.
204 204 */
205 205 /* ARGSUSED */
206 206 static ino64_t
207 207 zfsctl_root_inode_cb(vnode_t *vp, int index)
208 208 {
209 209 zfsvfs_t *zfsvfs = vp->v_vfsp->vfs_data;
210 210
211 211 ASSERT(index <= 2);
212 212
213 213 if (index == 0)
214 214 return (ZFSCTL_INO_SNAPDIR);
215 215
216 216 return (zfsvfs->z_shares_dir);
217 217 }
218 218
219 219 /*
220 220 * Create the '.zfs' directory. This directory is cached as part of the VFS
221 221 * structure. This results in a hold on the vfs_t. The code in zfs_umount()
222 222 * therefore checks against a vfs_count of 2 instead of 1. This reference
223 223 * is removed when the ctldir is destroyed in the unmount.
224 224 */
225 225 void
226 226 zfsctl_create(zfsvfs_t *zfsvfs)
227 227 {
228 228 vnode_t *vp, *rvp;
229 229 zfsctl_node_t *zcp;
230 230 uint64_t crtime[2];
231 231
232 232 ASSERT(zfsvfs->z_ctldir == NULL);
233 233
234 234 vp = gfs_root_create(sizeof (zfsctl_node_t), zfsvfs->z_vfs,
235 235 zfsctl_ops_root, ZFSCTL_INO_ROOT, zfsctl_root_entries,
236 236 zfsctl_root_inode_cb, MAXNAMELEN, NULL, NULL);
237 237 zcp = vp->v_data;
238 238 zcp->zc_id = ZFSCTL_INO_ROOT;
239 239
240 240 VERIFY(VFS_ROOT(zfsvfs->z_vfs, &rvp) == 0);
241 241 VERIFY(0 == sa_lookup(VTOZ(rvp)->z_sa_hdl, SA_ZPL_CRTIME(zfsvfs),
242 242 &crtime, sizeof (crtime)));
243 243 ZFS_TIME_DECODE(&zcp->zc_cmtime, crtime);
244 244 VN_RELE(rvp);
245 245
246 246 /*
247 247 * We're only faking the fact that we have a root of a filesystem for
248 248 * the sake of the GFS interfaces. Undo the flag manipulation it did
249 249 * for us.
250 250 */
251 251 vp->v_flag &= ~(VROOT | VNOCACHE | VNOMAP | VNOSWAP | VNOMOUNT);
252 252
253 253 zfsvfs->z_ctldir = vp;
254 254 }
255 255
256 256 /*
257 257 * Destroy the '.zfs' directory. Only called when the filesystem is unmounted.
258 258 * There might still be more references if we were force unmounted, but only
259 259 * new zfs_inactive() calls can occur and they don't reference .zfs
260 260 */
261 261 void
262 262 zfsctl_destroy(zfsvfs_t *zfsvfs)
263 263 {
264 264 VN_RELE(zfsvfs->z_ctldir);
265 265 zfsvfs->z_ctldir = NULL;
266 266 }
267 267
268 268 /*
269 269 * Given a root znode, retrieve the associated .zfs directory.
270 270 * Add a hold to the vnode and return it.
271 271 */
272 272 vnode_t *
273 273 zfsctl_root(znode_t *zp)
274 274 {
275 275 ASSERT(zfs_has_ctldir(zp));
276 276 VN_HOLD(zp->z_zfsvfs->z_ctldir);
277 277 return (zp->z_zfsvfs->z_ctldir);
278 278 }
279 279
280 280 /*
281 281 * Common open routine. Disallow any write access.
282 282 */
283 283 /* ARGSUSED */
284 284 static int
285 285 zfsctl_common_open(vnode_t **vpp, int flags, cred_t *cr, caller_context_t *ct)
286 286 {
287 287 if (flags & FWRITE)
288 288 return (SET_ERROR(EACCES));
289 289
290 290 return (0);
291 291 }
292 292
293 293 /*
294 294 * Common close routine. Nothing to do here.
295 295 */
296 296 /* ARGSUSED */
297 297 static int
298 298 zfsctl_common_close(vnode_t *vpp, int flags, int count, offset_t off,
299 299 cred_t *cr, caller_context_t *ct)
300 300 {
301 301 return (0);
302 302 }
303 303
304 304 /*
305 305 * Common access routine. Disallow writes.
306 306 */
307 307 /* ARGSUSED */
308 308 static int
309 309 zfsctl_common_access(vnode_t *vp, int mode, int flags, cred_t *cr,
310 310 caller_context_t *ct)
311 311 {
312 312 if (flags & V_ACE_MASK) {
313 313 if (mode & ACE_ALL_WRITE_PERMS)
314 314 return (SET_ERROR(EACCES));
315 315 } else {
316 316 if (mode & VWRITE)
317 317 return (SET_ERROR(EACCES));
318 318 }
319 319
320 320 return (0);
321 321 }
322 322
323 323 /*
324 324 * Common getattr function. Fill in basic information.
325 325 */
326 326 static void
327 327 zfsctl_common_getattr(vnode_t *vp, vattr_t *vap)
328 328 {
329 329 timestruc_t now;
330 330
331 331 vap->va_uid = 0;
332 332 vap->va_gid = 0;
333 333 vap->va_rdev = 0;
334 334 /*
335 335 * We are a purely virtual object, so we have no
336 336 * blocksize or allocated blocks.
337 337 */
338 338 vap->va_blksize = 0;
339 339 vap->va_nblocks = 0;
340 340 vap->va_seq = 0;
341 341 vap->va_fsid = vp->v_vfsp->vfs_dev;
342 342 vap->va_mode = S_IRUSR | S_IXUSR | S_IRGRP | S_IXGRP |
343 343 S_IROTH | S_IXOTH;
344 344 vap->va_type = VDIR;
345 345 /*
346 346 * We live in the now (for atime).
347 347 */
348 348 gethrestime(&now);
349 349 vap->va_atime = now;
350 350 }
351 351
352 352 /*ARGSUSED*/
353 353 static int
354 354 zfsctl_common_fid(vnode_t *vp, fid_t *fidp, caller_context_t *ct)
355 355 {
356 356 zfsvfs_t *zfsvfs = vp->v_vfsp->vfs_data;
357 357 zfsctl_node_t *zcp = vp->v_data;
358 358 uint64_t object = zcp->zc_id;
359 359 zfid_short_t *zfid;
360 360 int i;
361 361
362 362 ZFS_ENTER(zfsvfs);
363 363
364 364 if (fidp->fid_len < SHORT_FID_LEN) {
365 365 fidp->fid_len = SHORT_FID_LEN;
366 366 ZFS_EXIT(zfsvfs);
367 367 return (SET_ERROR(ENOSPC));
368 368 }
369 369
370 370 zfid = (zfid_short_t *)fidp;
371 371
372 372 zfid->zf_len = SHORT_FID_LEN;
373 373
374 374 for (i = 0; i < sizeof (zfid->zf_object); i++)
375 375 zfid->zf_object[i] = (uint8_t)(object >> (8 * i));
376 376
377 377 /* .zfs znodes always have a generation number of 0 */
378 378 for (i = 0; i < sizeof (zfid->zf_gen); i++)
379 379 zfid->zf_gen[i] = 0;
380 380
381 381 ZFS_EXIT(zfsvfs);
382 382 return (0);
383 383 }
384 384
385 385
386 386 /*ARGSUSED*/
387 387 static int
388 388 zfsctl_shares_fid(vnode_t *vp, fid_t *fidp, caller_context_t *ct)
389 389 {
390 390 zfsvfs_t *zfsvfs = vp->v_vfsp->vfs_data;
391 391 znode_t *dzp;
392 392 int error;
393 393
394 394 ZFS_ENTER(zfsvfs);
395 395
396 396 if (zfsvfs->z_shares_dir == 0) {
397 397 ZFS_EXIT(zfsvfs);
398 398 return (SET_ERROR(ENOTSUP));
399 399 }
400 400
401 401 if ((error = zfs_zget(zfsvfs, zfsvfs->z_shares_dir, &dzp)) == 0) {
402 402 error = VOP_FID(ZTOV(dzp), fidp, ct);
403 403 VN_RELE(ZTOV(dzp));
404 404 }
405 405
406 406 ZFS_EXIT(zfsvfs);
407 407 return (error);
408 408 }
409 409 /*
410 410 * .zfs inode namespace
411 411 *
412 412 * We need to generate unique inode numbers for all files and directories
413 413 * within the .zfs pseudo-filesystem. We use the following scheme:
414 414 *
415 415 * ENTRY ZFSCTL_INODE
416 416 * .zfs 1
417 417 * .zfs/snapshot 2
418 418 * .zfs/snapshot/<snap> objectid(snap)
419 419 */
420 420
421 421 #define ZFSCTL_INO_SNAP(id) (id)
422 422
423 423 /*
424 424 * Get root directory attributes.
425 425 */
426 426 /* ARGSUSED */
427 427 static int
428 428 zfsctl_root_getattr(vnode_t *vp, vattr_t *vap, int flags, cred_t *cr,
429 429 caller_context_t *ct)
430 430 {
431 431 zfsvfs_t *zfsvfs = vp->v_vfsp->vfs_data;
432 432 zfsctl_node_t *zcp = vp->v_data;
433 433
434 434 ZFS_ENTER(zfsvfs);
435 435 vap->va_nodeid = ZFSCTL_INO_ROOT;
436 436 vap->va_nlink = vap->va_size = NROOT_ENTRIES;
437 437 vap->va_mtime = vap->va_ctime = zcp->zc_cmtime;
438 438
439 439 zfsctl_common_getattr(vp, vap);
440 440 ZFS_EXIT(zfsvfs);
441 441
442 442 return (0);
443 443 }
444 444
445 445 /*
446 446 * Special case the handling of "..".
447 447 */
448 448 /* ARGSUSED */
449 449 int
450 450 zfsctl_root_lookup(vnode_t *dvp, char *nm, vnode_t **vpp, pathname_t *pnp,
451 451 int flags, vnode_t *rdir, cred_t *cr, caller_context_t *ct,
452 452 int *direntflags, pathname_t *realpnp)
453 453 {
454 454 zfsvfs_t *zfsvfs = dvp->v_vfsp->vfs_data;
455 455 int err;
456 456
457 457 /*
458 458 * No extended attributes allowed under .zfs
459 459 */
460 460 if (flags & LOOKUP_XATTR)
461 461 return (SET_ERROR(EINVAL));
462 462
463 463 ZFS_ENTER(zfsvfs);
464 464
465 465 if (strcmp(nm, "..") == 0) {
466 466 err = VFS_ROOT(dvp->v_vfsp, vpp);
467 467 } else {
468 468 err = gfs_vop_lookup(dvp, nm, vpp, pnp, flags, rdir,
469 469 cr, ct, direntflags, realpnp);
470 470 }
471 471
472 472 ZFS_EXIT(zfsvfs);
473 473
474 474 return (err);
475 475 }
476 476
477 477 static int
478 478 zfsctl_pathconf(vnode_t *vp, int cmd, ulong_t *valp, cred_t *cr,
479 479 caller_context_t *ct)
480 480 {
481 481 /*
482 482 * We only care about ACL_ENABLED so that libsec can
483 483 * display ACL correctly and not default to POSIX draft.
484 484 */
485 485 if (cmd == _PC_ACL_ENABLED) {
486 486 *valp = _ACL_ACE_ENABLED;
487 487 return (0);
488 488 }
489 489
490 490 return (fs_pathconf(vp, cmd, valp, cr, ct));
491 491 }
492 492
493 493 static const fs_operation_def_t zfsctl_tops_root[] = {
494 494 { VOPNAME_OPEN, { .vop_open = zfsctl_common_open } },
495 495 { VOPNAME_CLOSE, { .vop_close = zfsctl_common_close } },
496 496 { VOPNAME_IOCTL, { .error = fs_inval } },
497 497 { VOPNAME_GETATTR, { .vop_getattr = zfsctl_root_getattr } },
498 498 { VOPNAME_ACCESS, { .vop_access = zfsctl_common_access } },
499 499 { VOPNAME_READDIR, { .vop_readdir = gfs_vop_readdir } },
500 500 { VOPNAME_LOOKUP, { .vop_lookup = zfsctl_root_lookup } },
501 501 { VOPNAME_SEEK, { .vop_seek = fs_seek } },
502 502 { VOPNAME_INACTIVE, { .vop_inactive = gfs_vop_inactive } },
503 503 { VOPNAME_PATHCONF, { .vop_pathconf = zfsctl_pathconf } },
504 504 { VOPNAME_FID, { .vop_fid = zfsctl_common_fid } },
505 505 { NULL }
506 506 };
507 507
508 508 /*
509 509 * Gets the full dataset name that corresponds to the given snapshot name
510 510 * Example:
511 511 * zfsctl_snapshot_zname("snap1") -> "mypool/myfs@snap1"
512 512 */
513 513 static int
514 514 zfsctl_snapshot_zname(vnode_t *vp, const char *name, int len, char *zname)
515 515 {
516 516 objset_t *os = ((zfsvfs_t *)((vp)->v_vfsp->vfs_data))->z_os;
517 517
518 518 if (snapshot_namecheck(name, NULL, NULL) != 0)
519 519 return (SET_ERROR(EILSEQ));
520 520 dmu_objset_name(os, zname);
521 521 if (strlen(zname) + 1 + strlen(name) >= len)
522 522 return (SET_ERROR(ENAMETOOLONG));
523 523 (void) strcat(zname, "@");
524 524 (void) strcat(zname, name);
525 525 return (0);
526 526 }
527 527
528 528 static int
529 529 zfsctl_unmount_snap(zfs_snapentry_t *sep, int fflags, cred_t *cr)
530 530 {
531 531 vnode_t *svp = sep->se_root;
532 532 int error;
533 533
534 534 ASSERT(vn_ismntpt(svp));
535 535
536 536 /* this will be dropped by dounmount() */
537 537 if ((error = vn_vfswlock(svp)) != 0)
538 538 return (error);
539 539
540 540 VN_HOLD(svp);
541 541 error = dounmount(vn_mountedvfs(svp), fflags, cr);
542 542 if (error) {
543 543 VN_RELE(svp);
544 544 return (error);
545 545 }
546 546
547 547 /*
548 548 * We can't use VN_RELE(), as that will try to invoke
549 549 * zfsctl_snapdir_inactive(), which would cause us to destroy
550 550 * the sd_lock mutex held by our caller.
551 551 */
552 552 ASSERT(svp->v_count == 1);
553 553 gfs_vop_inactive(svp, cr, NULL);
554 554
555 555 kmem_free(sep->se_name, strlen(sep->se_name) + 1);
556 556 kmem_free(sep, sizeof (zfs_snapentry_t));
557 557
558 558 return (0);
559 559 }
560 560
561 561 static void
562 562 zfsctl_rename_snap(zfsctl_snapdir_t *sdp, zfs_snapentry_t *sep, const char *nm)
563 563 {
564 564 avl_index_t where;
565 565 vfs_t *vfsp;
566 566 refstr_t *pathref;
567 567 char newpath[MAXNAMELEN];
568 568 char *tail;
569 569
570 570 ASSERT(MUTEX_HELD(&sdp->sd_lock));
571 571 ASSERT(sep != NULL);
572 572
573 573 vfsp = vn_mountedvfs(sep->se_root);
574 574 ASSERT(vfsp != NULL);
575 575
576 576 vfs_lock_wait(vfsp);
577 577
578 578 /*
579 579 * Change the name in the AVL tree.
580 580 */
581 581 avl_remove(&sdp->sd_snaps, sep);
582 582 kmem_free(sep->se_name, strlen(sep->se_name) + 1);
583 583 sep->se_name = kmem_alloc(strlen(nm) + 1, KM_SLEEP);
584 584 (void) strcpy(sep->se_name, nm);
585 585 VERIFY(avl_find(&sdp->sd_snaps, sep, &where) == NULL);
586 586 avl_insert(&sdp->sd_snaps, sep, where);
587 587
588 588 /*
589 589 * Change the current mountpoint info:
590 590 * - update the tail of the mntpoint path
591 591 * - update the tail of the resource path
592 592 */
593 593 pathref = vfs_getmntpoint(vfsp);
594 594 (void) strncpy(newpath, refstr_value(pathref), sizeof (newpath));
595 595 VERIFY((tail = strrchr(newpath, '/')) != NULL);
596 596 *(tail+1) = '\0';
597 597 ASSERT3U(strlen(newpath) + strlen(nm), <, sizeof (newpath));
598 598 (void) strcat(newpath, nm);
599 599 refstr_rele(pathref);
600 600 vfs_setmntpoint(vfsp, newpath, 0);
601 601
602 602 pathref = vfs_getresource(vfsp);
603 603 (void) strncpy(newpath, refstr_value(pathref), sizeof (newpath));
604 604 VERIFY((tail = strrchr(newpath, '@')) != NULL);
605 605 *(tail+1) = '\0';
606 606 ASSERT3U(strlen(newpath) + strlen(nm), <, sizeof (newpath));
607 607 (void) strcat(newpath, nm);
608 608 refstr_rele(pathref);
609 609 vfs_setresource(vfsp, newpath, 0);
610 610
611 611 vfs_unlock(vfsp);
612 612 }
613 613
614 614 /*ARGSUSED*/
615 615 static int
616 616 zfsctl_snapdir_rename(vnode_t *sdvp, char *snm, vnode_t *tdvp, char *tnm,
617 617 cred_t *cr, caller_context_t *ct, int flags)
618 618 {
619 619 zfsctl_snapdir_t *sdp = sdvp->v_data;
620 620 zfs_snapentry_t search, *sep;
621 621 zfsvfs_t *zfsvfs;
622 622 avl_index_t where;
623 623 char from[MAXNAMELEN], to[MAXNAMELEN];
624 624 char real[MAXNAMELEN], fsname[MAXNAMELEN];
625 625 int err;
626 626
627 627 zfsvfs = sdvp->v_vfsp->vfs_data;
628 628 ZFS_ENTER(zfsvfs);
629 629
630 630 if ((flags & FIGNORECASE) || zfsvfs->z_case == ZFS_CASE_INSENSITIVE) {
631 631 err = dmu_snapshot_realname(zfsvfs->z_os, snm, real,
632 632 MAXNAMELEN, NULL);
633 633 if (err == 0) {
634 634 snm = real;
635 635 } else if (err != ENOTSUP) {
636 636 ZFS_EXIT(zfsvfs);
637 637 return (err);
638 638 }
639 639 }
640 640
641 641 ZFS_EXIT(zfsvfs);
642 642
643 643 dmu_objset_name(zfsvfs->z_os, fsname);
644 644
645 645 err = zfsctl_snapshot_zname(sdvp, snm, MAXNAMELEN, from);
646 646 if (err == 0)
647 647 err = zfsctl_snapshot_zname(tdvp, tnm, MAXNAMELEN, to);
648 648 if (err == 0)
649 649 err = zfs_secpolicy_rename_perms(from, to, cr);
650 650 if (err != 0)
651 651 return (err);
652 652
653 653 /*
654 654 * Cannot move snapshots out of the snapdir.
655 655 */
656 656 if (sdvp != tdvp)
657 657 return (SET_ERROR(EINVAL));
658 658
659 659 if (strcmp(snm, tnm) == 0)
660 660 return (0);
661 661
662 662 mutex_enter(&sdp->sd_lock);
663 663
664 664 search.se_name = (char *)snm;
665 665 if ((sep = avl_find(&sdp->sd_snaps, &search, &where)) == NULL) {
666 666 mutex_exit(&sdp->sd_lock);
667 667 return (SET_ERROR(ENOENT));
668 668 }
669 669
670 670 err = dsl_dataset_rename_snapshot(fsname, snm, tnm, B_FALSE);
671 671 if (err == 0)
672 672 zfsctl_rename_snap(sdp, sep, tnm);
673 673
674 674 mutex_exit(&sdp->sd_lock);
675 675
676 676 return (err);
677 677 }
678 678
679 679 /* ARGSUSED */
680 680 static int
681 681 zfsctl_snapdir_remove(vnode_t *dvp, char *name, vnode_t *cwd, cred_t *cr,
682 682 caller_context_t *ct, int flags)
683 683 {
684 684 zfsctl_snapdir_t *sdp = dvp->v_data;
685 685 zfs_snapentry_t *sep;
686 686 zfs_snapentry_t search;
687 687 zfsvfs_t *zfsvfs;
688 688 char snapname[MAXNAMELEN];
689 689 char real[MAXNAMELEN];
690 690 int err;
691 691
692 692 zfsvfs = dvp->v_vfsp->vfs_data;
693 693 ZFS_ENTER(zfsvfs);
694 694
695 695 if ((flags & FIGNORECASE) || zfsvfs->z_case == ZFS_CASE_INSENSITIVE) {
696 696
697 697 err = dmu_snapshot_realname(zfsvfs->z_os, name, real,
698 698 MAXNAMELEN, NULL);
699 699 if (err == 0) {
700 700 name = real;
701 701 } else if (err != ENOTSUP) {
702 702 ZFS_EXIT(zfsvfs);
703 703 return (err);
704 704 }
705 705 }
706 706
707 707 ZFS_EXIT(zfsvfs);
708 708
709 709 err = zfsctl_snapshot_zname(dvp, name, MAXNAMELEN, snapname);
710 710 if (err == 0)
711 711 err = zfs_secpolicy_destroy_perms(snapname, cr);
712 712 if (err != 0)
713 713 return (err);
714 714
715 715 mutex_enter(&sdp->sd_lock);
716 716
717 717 search.se_name = name;
718 718 sep = avl_find(&sdp->sd_snaps, &search, NULL);
719 719 if (sep) {
720 720 avl_remove(&sdp->sd_snaps, sep);
721 721 err = zfsctl_unmount_snap(sep, MS_FORCE, cr);
722 722 if (err != 0)
723 723 avl_add(&sdp->sd_snaps, sep);
724 724 else
725 725 err = dsl_destroy_snapshot(snapname, B_FALSE);
726 726 } else {
727 727 err = SET_ERROR(ENOENT);
728 728 }
729 729
730 730 mutex_exit(&sdp->sd_lock);
731 731
732 732 return (err);
733 733 }
734 734
735 735 /*
736 736 * This creates a snapshot under '.zfs/snapshot'.
737 737 */
738 738 /* ARGSUSED */
739 739 static int
740 740 zfsctl_snapdir_mkdir(vnode_t *dvp, char *dirname, vattr_t *vap, vnode_t **vpp,
741 741 cred_t *cr, caller_context_t *cc, int flags, vsecattr_t *vsecp)
742 742 {
743 743 zfsvfs_t *zfsvfs = dvp->v_vfsp->vfs_data;
744 744 char name[MAXNAMELEN];
745 745 int err;
746 746 static enum symfollow follow = NO_FOLLOW;
747 747 static enum uio_seg seg = UIO_SYSSPACE;
748 748
749 749 if (snapshot_namecheck(dirname, NULL, NULL) != 0)
750 750 return (SET_ERROR(EILSEQ));
751 751
752 752 dmu_objset_name(zfsvfs->z_os, name);
753 753
754 754 *vpp = NULL;
755 755
756 756 err = zfs_secpolicy_snapshot_perms(name, cr);
757 757 if (err != 0)
758 758 return (err);
759 759
760 760 if (err == 0) {
761 761 err = dmu_objset_snapshot_one(name, dirname);
762 762 if (err != 0)
763 763 return (err);
764 764 err = lookupnameat(dirname, seg, follow, NULL, vpp, dvp);
765 765 }
766 766
767 767 return (err);
768 768 }
769 769
770 770 /*
771 771 * Lookup entry point for the 'snapshot' directory. Try to open the
772 772 * snapshot if it exist, creating the pseudo filesystem vnode as necessary.
773 773 * Perform a mount of the associated dataset on top of the vnode.
774 774 */
775 775 /* ARGSUSED */
776 776 static int
777 777 zfsctl_snapdir_lookup(vnode_t *dvp, char *nm, vnode_t **vpp, pathname_t *pnp,
778 778 int flags, vnode_t *rdir, cred_t *cr, caller_context_t *ct,
779 779 int *direntflags, pathname_t *realpnp)
780 780 {
781 781 zfsctl_snapdir_t *sdp = dvp->v_data;
782 782 objset_t *snap;
783 783 char snapname[MAXNAMELEN];
784 784 char real[MAXNAMELEN];
785 785 char *mountpoint;
786 786 zfs_snapentry_t *sep, search;
787 787 struct mounta margs;
788 788 vfs_t *vfsp;
789 789 size_t mountpoint_len;
790 790 avl_index_t where;
791 791 zfsvfs_t *zfsvfs = dvp->v_vfsp->vfs_data;
792 792 int err;
793 793
794 794 /*
795 795 * No extended attributes allowed under .zfs
796 796 */
797 797 if (flags & LOOKUP_XATTR)
798 798 return (SET_ERROR(EINVAL));
799 799
800 800 ASSERT(dvp->v_type == VDIR);
801 801
802 802 /*
803 803 * If we get a recursive call, that means we got called
804 804 * from the domount() code while it was trying to look up the
805 805 * spec (which looks like a local path for zfs). We need to
806 806 * add some flag to domount() to tell it not to do this lookup.
807 807 */
808 808 if (MUTEX_HELD(&sdp->sd_lock))
809 809 return (SET_ERROR(ENOENT));
810 810
811 811 ZFS_ENTER(zfsvfs);
812 812
813 813 if (gfs_lookup_dot(vpp, dvp, zfsvfs->z_ctldir, nm) == 0) {
814 814 ZFS_EXIT(zfsvfs);
815 815 return (0);
816 816 }
817 817
818 818 if (flags & FIGNORECASE) {
819 819 boolean_t conflict = B_FALSE;
820 820
821 821 err = dmu_snapshot_realname(zfsvfs->z_os, nm, real,
822 822 MAXNAMELEN, &conflict);
823 823 if (err == 0) {
824 824 nm = real;
825 825 } else if (err != ENOTSUP) {
826 826 ZFS_EXIT(zfsvfs);
827 827 return (err);
828 828 }
829 829 if (realpnp)
830 830 (void) strlcpy(realpnp->pn_buf, nm,
831 831 realpnp->pn_bufsize);
832 832 if (conflict && direntflags)
833 833 *direntflags = ED_CASE_CONFLICT;
834 834 }
835 835
836 836 mutex_enter(&sdp->sd_lock);
837 837 search.se_name = (char *)nm;
838 838 if ((sep = avl_find(&sdp->sd_snaps, &search, &where)) != NULL) {
839 839 *vpp = sep->se_root;
840 840 VN_HOLD(*vpp);
841 841 err = traverse(vpp);
842 842 if (err != 0) {
843 843 VN_RELE(*vpp);
844 844 *vpp = NULL;
845 845 } else if (*vpp == sep->se_root) {
846 846 /*
847 847 * The snapshot was unmounted behind our backs,
848 848 * try to remount it.
849 849 */
850 850 goto domount;
851 851 } else {
852 852 /*
853 853 * VROOT was set during the traverse call. We need
854 854 * to clear it since we're pretending to be part
855 855 * of our parent's vfs.
856 856 */
857 857 (*vpp)->v_flag &= ~VROOT;
858 858 }
859 859 mutex_exit(&sdp->sd_lock);
860 860 ZFS_EXIT(zfsvfs);
861 861 return (err);
862 862 }
863 863
864 864 /*
865 865 * The requested snapshot is not currently mounted, look it up.
866 866 */
867 867 err = zfsctl_snapshot_zname(dvp, nm, MAXNAMELEN, snapname);
868 868 if (err != 0) {
869 869 mutex_exit(&sdp->sd_lock);
870 870 ZFS_EXIT(zfsvfs);
871 871 /*
872 872 * handle "ls *" or "?" in a graceful manner,
873 873 * forcing EILSEQ to ENOENT.
874 874 * Since shell ultimately passes "*" or "?" as name to lookup
875 875 */
876 876 return (err == EILSEQ ? ENOENT : err);
877 877 }
878 878 if (dmu_objset_hold(snapname, FTAG, &snap) != 0) {
879 879 mutex_exit(&sdp->sd_lock);
880 880 ZFS_EXIT(zfsvfs);
881 881 return (SET_ERROR(ENOENT));
882 882 }
883 883
884 884 sep = kmem_alloc(sizeof (zfs_snapentry_t), KM_SLEEP);
885 885 sep->se_name = kmem_alloc(strlen(nm) + 1, KM_SLEEP);
886 886 (void) strcpy(sep->se_name, nm);
887 887 *vpp = sep->se_root = zfsctl_snapshot_mknode(dvp, dmu_objset_id(snap));
888 888 avl_insert(&sdp->sd_snaps, sep, where);
889 889
890 890 dmu_objset_rele(snap, FTAG);
891 891 domount:
892 892 mountpoint_len = strlen(refstr_value(dvp->v_vfsp->vfs_mntpt)) +
893 893 strlen("/.zfs/snapshot/") + strlen(nm) + 1;
894 894 mountpoint = kmem_alloc(mountpoint_len, KM_SLEEP);
895 895 (void) snprintf(mountpoint, mountpoint_len, "%s/.zfs/snapshot/%s",
896 896 refstr_value(dvp->v_vfsp->vfs_mntpt), nm);
897 897
898 898 margs.spec = snapname;
899 899 margs.dir = mountpoint;
900 900 margs.flags = MS_SYSSPACE | MS_NOMNTTAB;
901 901 margs.fstype = "zfs";
902 902 margs.dataptr = NULL;
903 903 margs.datalen = 0;
904 904 margs.optptr = NULL;
905 905 margs.optlen = 0;
906 906
907 907 err = domount("zfs", &margs, *vpp, kcred, &vfsp);
908 908 kmem_free(mountpoint, mountpoint_len);
909 909
910 910 if (err == 0) {
911 911 /*
912 912 * Return the mounted root rather than the covered mount point.
913 913 * Takes the GFS vnode at .zfs/snapshot/<snapname> and returns
914 914 * the ZFS vnode mounted on top of the GFS node. This ZFS
915 915 * vnode is the root of the newly created vfsp.
916 916 */
917 917 VFS_RELE(vfsp);
918 918 err = traverse(vpp);
919 919 }
920 920
921 921 if (err == 0) {
922 922 /*
923 923 * Fix up the root vnode mounted on .zfs/snapshot/<snapname>.
924 924 *
925 925 * This is where we lie about our v_vfsp in order to
926 926 * make .zfs/snapshot/<snapname> accessible over NFS
927 927 * without requiring manual mounts of <snapname>.
928 928 */
929 929 ASSERT(VTOZ(*vpp)->z_zfsvfs != zfsvfs);
930 930 VTOZ(*vpp)->z_zfsvfs->z_parent = zfsvfs;
931 931 (*vpp)->v_vfsp = zfsvfs->z_vfs;
932 932 (*vpp)->v_flag &= ~VROOT;
933 933 }
934 934 mutex_exit(&sdp->sd_lock);
935 935 ZFS_EXIT(zfsvfs);
936 936
937 937 /*
938 938 * If we had an error, drop our hold on the vnode and
939 939 * zfsctl_snapshot_inactive() will clean up.
940 940 */
941 941 if (err != 0) {
942 942 VN_RELE(*vpp);
943 943 *vpp = NULL;
944 944 }
945 945 return (err);
946 946 }
947 947
948 948 /* ARGSUSED */
949 949 static int
950 950 zfsctl_shares_lookup(vnode_t *dvp, char *nm, vnode_t **vpp, pathname_t *pnp,
951 951 int flags, vnode_t *rdir, cred_t *cr, caller_context_t *ct,
952 952 int *direntflags, pathname_t *realpnp)
953 953 {
954 954 zfsvfs_t *zfsvfs = dvp->v_vfsp->vfs_data;
955 955 znode_t *dzp;
956 956 int error;
957 957
958 958 ZFS_ENTER(zfsvfs);
959 959
960 960 if (gfs_lookup_dot(vpp, dvp, zfsvfs->z_ctldir, nm) == 0) {
961 961 ZFS_EXIT(zfsvfs);
962 962 return (0);
963 963 }
964 964
965 965 if (zfsvfs->z_shares_dir == 0) {
966 966 ZFS_EXIT(zfsvfs);
967 967 return (SET_ERROR(ENOTSUP));
968 968 }
969 969 if ((error = zfs_zget(zfsvfs, zfsvfs->z_shares_dir, &dzp)) == 0)
970 970 error = VOP_LOOKUP(ZTOV(dzp), nm, vpp, pnp,
971 971 flags, rdir, cr, ct, direntflags, realpnp);
972 972
973 973 VN_RELE(ZTOV(dzp));
974 974 ZFS_EXIT(zfsvfs);
975 975
976 976 return (error);
977 977 }
978 978
979 979 /* ARGSUSED */
980 980 static int
981 981 zfsctl_snapdir_readdir_cb(vnode_t *vp, void *dp, int *eofp,
982 982 offset_t *offp, offset_t *nextp, void *data, int flags)
983 983 {
984 984 zfsvfs_t *zfsvfs = vp->v_vfsp->vfs_data;
985 985 char snapname[MAXNAMELEN];
986 986 uint64_t id, cookie;
987 987 boolean_t case_conflict;
988 988 int error;
989 989
990 990 ZFS_ENTER(zfsvfs);
991 991
992 992 cookie = *offp;
993 993 dsl_pool_config_enter(dmu_objset_pool(zfsvfs->z_os), FTAG);
994 994 error = dmu_snapshot_list_next(zfsvfs->z_os, MAXNAMELEN, snapname, &id,
995 995 &cookie, &case_conflict);
996 996 dsl_pool_config_exit(dmu_objset_pool(zfsvfs->z_os), FTAG);
997 997 if (error) {
998 998 ZFS_EXIT(zfsvfs);
999 999 if (error == ENOENT) {
1000 1000 *eofp = 1;
1001 1001 return (0);
1002 1002 }
1003 1003 return (error);
1004 1004 }
1005 1005
1006 1006 if (flags & V_RDDIR_ENTFLAGS) {
1007 1007 edirent_t *eodp = dp;
1008 1008
1009 1009 (void) strcpy(eodp->ed_name, snapname);
1010 1010 eodp->ed_ino = ZFSCTL_INO_SNAP(id);
1011 1011 eodp->ed_eflags = case_conflict ? ED_CASE_CONFLICT : 0;
1012 1012 } else {
1013 1013 struct dirent64 *odp = dp;
1014 1014
1015 1015 (void) strcpy(odp->d_name, snapname);
1016 1016 odp->d_ino = ZFSCTL_INO_SNAP(id);
1017 1017 }
1018 1018 *nextp = cookie;
1019 1019
1020 1020 ZFS_EXIT(zfsvfs);
1021 1021
1022 1022 return (0);
1023 1023 }
1024 1024
1025 1025 /* ARGSUSED */
1026 1026 static int
1027 1027 zfsctl_shares_readdir(vnode_t *vp, uio_t *uiop, cred_t *cr, int *eofp,
1028 1028 caller_context_t *ct, int flags)
1029 1029 {
1030 1030 zfsvfs_t *zfsvfs = vp->v_vfsp->vfs_data;
1031 1031 znode_t *dzp;
1032 1032 int error;
1033 1033
1034 1034 ZFS_ENTER(zfsvfs);
1035 1035
1036 1036 if (zfsvfs->z_shares_dir == 0) {
1037 1037 ZFS_EXIT(zfsvfs);
1038 1038 return (SET_ERROR(ENOTSUP));
1039 1039 }
1040 1040 if ((error = zfs_zget(zfsvfs, zfsvfs->z_shares_dir, &dzp)) == 0) {
1041 1041 error = VOP_READDIR(ZTOV(dzp), uiop, cr, eofp, ct, flags);
1042 1042 VN_RELE(ZTOV(dzp));
1043 1043 } else {
↓ open down ↓ |
1043 lines elided |
↑ open up ↑ |
1044 1044 *eofp = 1;
1045 1045 error = SET_ERROR(ENOENT);
1046 1046 }
1047 1047
1048 1048 ZFS_EXIT(zfsvfs);
1049 1049 return (error);
1050 1050 }
1051 1051
1052 1052 /*
1053 1053 * pvp is the '.zfs' directory (zfsctl_node_t).
1054 + *
1054 1055 * Creates vp, which is '.zfs/snapshot' (zfsctl_snapdir_t).
1055 1056 *
1056 1057 * This function is the callback to create a GFS vnode for '.zfs/snapshot'
1057 1058 * when a lookup is performed on .zfs for "snapshot".
1058 1059 */
1059 1060 vnode_t *
1060 1061 zfsctl_mknode_snapdir(vnode_t *pvp)
1061 1062 {
1062 1063 vnode_t *vp;
1063 1064 zfsctl_snapdir_t *sdp;
1064 1065
1065 1066 vp = gfs_dir_create(sizeof (zfsctl_snapdir_t), pvp,
1066 1067 zfsctl_ops_snapdir, NULL, NULL, MAXNAMELEN,
1067 1068 zfsctl_snapdir_readdir_cb, NULL);
1068 1069 sdp = vp->v_data;
1069 1070 sdp->sd_node.zc_id = ZFSCTL_INO_SNAPDIR;
1070 1071 sdp->sd_node.zc_cmtime = ((zfsctl_node_t *)pvp->v_data)->zc_cmtime;
1071 1072 mutex_init(&sdp->sd_lock, NULL, MUTEX_DEFAULT, NULL);
1072 1073 avl_create(&sdp->sd_snaps, snapentry_compare,
1073 1074 sizeof (zfs_snapentry_t), offsetof(zfs_snapentry_t, se_node));
1074 1075 return (vp);
1075 1076 }
1076 1077
1077 1078 vnode_t *
1078 1079 zfsctl_mknode_shares(vnode_t *pvp)
1079 1080 {
1080 1081 vnode_t *vp;
1081 1082 zfsctl_node_t *sdp;
1082 1083
1083 1084 vp = gfs_dir_create(sizeof (zfsctl_node_t), pvp,
1084 1085 zfsctl_ops_shares, NULL, NULL, MAXNAMELEN,
1085 1086 NULL, NULL);
1086 1087 sdp = vp->v_data;
1087 1088 sdp->zc_cmtime = ((zfsctl_node_t *)pvp->v_data)->zc_cmtime;
1088 1089 return (vp);
1089 1090
1090 1091 }
1091 1092
1092 1093 /* ARGSUSED */
1093 1094 static int
1094 1095 zfsctl_shares_getattr(vnode_t *vp, vattr_t *vap, int flags, cred_t *cr,
1095 1096 caller_context_t *ct)
1096 1097 {
1097 1098 zfsvfs_t *zfsvfs = vp->v_vfsp->vfs_data;
1098 1099 znode_t *dzp;
1099 1100 int error;
1100 1101
1101 1102 ZFS_ENTER(zfsvfs);
1102 1103 if (zfsvfs->z_shares_dir == 0) {
1103 1104 ZFS_EXIT(zfsvfs);
1104 1105 return (SET_ERROR(ENOTSUP));
1105 1106 }
1106 1107 if ((error = zfs_zget(zfsvfs, zfsvfs->z_shares_dir, &dzp)) == 0) {
1107 1108 error = VOP_GETATTR(ZTOV(dzp), vap, flags, cr, ct);
1108 1109 VN_RELE(ZTOV(dzp));
1109 1110 }
1110 1111 ZFS_EXIT(zfsvfs);
1111 1112 return (error);
1112 1113
1113 1114
1114 1115 }
1115 1116
1116 1117 /* ARGSUSED */
1117 1118 static int
1118 1119 zfsctl_snapdir_getattr(vnode_t *vp, vattr_t *vap, int flags, cred_t *cr,
1119 1120 caller_context_t *ct)
1120 1121 {
1121 1122 zfsvfs_t *zfsvfs = vp->v_vfsp->vfs_data;
1122 1123 zfsctl_snapdir_t *sdp = vp->v_data;
1123 1124
1124 1125 ZFS_ENTER(zfsvfs);
1125 1126 zfsctl_common_getattr(vp, vap);
1126 1127 vap->va_nodeid = gfs_file_inode(vp);
1127 1128 vap->va_nlink = vap->va_size = avl_numnodes(&sdp->sd_snaps) + 2;
1128 1129 vap->va_ctime = vap->va_mtime = dmu_objset_snap_cmtime(zfsvfs->z_os);
1129 1130 ZFS_EXIT(zfsvfs);
1130 1131
1131 1132 return (0);
1132 1133 }
1133 1134
1134 1135 /* ARGSUSED */
1135 1136 static void
1136 1137 zfsctl_snapdir_inactive(vnode_t *vp, cred_t *cr, caller_context_t *ct)
1137 1138 {
1138 1139 zfsctl_snapdir_t *sdp = vp->v_data;
1139 1140 void *private;
1140 1141
1141 1142 private = gfs_dir_inactive(vp);
1142 1143 if (private != NULL) {
1143 1144 ASSERT(avl_numnodes(&sdp->sd_snaps) == 0);
1144 1145 mutex_destroy(&sdp->sd_lock);
1145 1146 avl_destroy(&sdp->sd_snaps);
1146 1147 kmem_free(private, sizeof (zfsctl_snapdir_t));
1147 1148 }
1148 1149 }
1149 1150
1150 1151 static const fs_operation_def_t zfsctl_tops_snapdir[] = {
1151 1152 { VOPNAME_OPEN, { .vop_open = zfsctl_common_open } },
1152 1153 { VOPNAME_CLOSE, { .vop_close = zfsctl_common_close } },
1153 1154 { VOPNAME_IOCTL, { .error = fs_inval } },
1154 1155 { VOPNAME_GETATTR, { .vop_getattr = zfsctl_snapdir_getattr } },
1155 1156 { VOPNAME_ACCESS, { .vop_access = zfsctl_common_access } },
1156 1157 { VOPNAME_RENAME, { .vop_rename = zfsctl_snapdir_rename } },
1157 1158 { VOPNAME_RMDIR, { .vop_rmdir = zfsctl_snapdir_remove } },
1158 1159 { VOPNAME_MKDIR, { .vop_mkdir = zfsctl_snapdir_mkdir } },
1159 1160 { VOPNAME_READDIR, { .vop_readdir = gfs_vop_readdir } },
1160 1161 { VOPNAME_LOOKUP, { .vop_lookup = zfsctl_snapdir_lookup } },
1161 1162 { VOPNAME_SEEK, { .vop_seek = fs_seek } },
1162 1163 { VOPNAME_INACTIVE, { .vop_inactive = zfsctl_snapdir_inactive } },
1163 1164 { VOPNAME_FID, { .vop_fid = zfsctl_common_fid } },
1164 1165 { NULL }
1165 1166 };
1166 1167
1167 1168 static const fs_operation_def_t zfsctl_tops_shares[] = {
1168 1169 { VOPNAME_OPEN, { .vop_open = zfsctl_common_open } },
1169 1170 { VOPNAME_CLOSE, { .vop_close = zfsctl_common_close } },
1170 1171 { VOPNAME_IOCTL, { .error = fs_inval } },
1171 1172 { VOPNAME_GETATTR, { .vop_getattr = zfsctl_shares_getattr } },
1172 1173 { VOPNAME_ACCESS, { .vop_access = zfsctl_common_access } },
1173 1174 { VOPNAME_READDIR, { .vop_readdir = zfsctl_shares_readdir } },
1174 1175 { VOPNAME_LOOKUP, { .vop_lookup = zfsctl_shares_lookup } },
1175 1176 { VOPNAME_SEEK, { .vop_seek = fs_seek } },
1176 1177 { VOPNAME_INACTIVE, { .vop_inactive = gfs_vop_inactive } },
1177 1178 { VOPNAME_FID, { .vop_fid = zfsctl_shares_fid } },
1178 1179 { NULL }
1179 1180 };
1180 1181
1181 1182 /*
1182 1183 * pvp is the GFS vnode '.zfs/snapshot'.
1183 1184 *
1184 1185 * This creates a GFS node under '.zfs/snapshot' representing each
1185 1186 * snapshot. This newly created GFS node is what we mount snapshot
1186 1187 * vfs_t's ontop of.
1187 1188 */
1188 1189 static vnode_t *
1189 1190 zfsctl_snapshot_mknode(vnode_t *pvp, uint64_t objset)
1190 1191 {
1191 1192 vnode_t *vp;
1192 1193 zfsctl_node_t *zcp;
1193 1194
1194 1195 vp = gfs_dir_create(sizeof (zfsctl_node_t), pvp,
1195 1196 zfsctl_ops_snapshot, NULL, NULL, MAXNAMELEN, NULL, NULL);
1196 1197 zcp = vp->v_data;
1197 1198 zcp->zc_id = objset;
1198 1199
1199 1200 return (vp);
1200 1201 }
1201 1202
1202 1203 static void
1203 1204 zfsctl_snapshot_inactive(vnode_t *vp, cred_t *cr, caller_context_t *ct)
1204 1205 {
1205 1206 zfsctl_snapdir_t *sdp;
1206 1207 zfs_snapentry_t *sep, *next;
1207 1208 vnode_t *dvp;
1208 1209
1209 1210 VERIFY(gfs_dir_lookup(vp, "..", &dvp, cr, 0, NULL, NULL) == 0);
1210 1211 sdp = dvp->v_data;
1211 1212
1212 1213 mutex_enter(&sdp->sd_lock);
1213 1214
1214 1215 if (vp->v_count > 1) {
1215 1216 mutex_exit(&sdp->sd_lock);
1216 1217 return;
1217 1218 }
1218 1219 ASSERT(!vn_ismntpt(vp));
1219 1220
1220 1221 sep = avl_first(&sdp->sd_snaps);
1221 1222 while (sep != NULL) {
1222 1223 next = AVL_NEXT(&sdp->sd_snaps, sep);
1223 1224
1224 1225 if (sep->se_root == vp) {
1225 1226 avl_remove(&sdp->sd_snaps, sep);
1226 1227 kmem_free(sep->se_name, strlen(sep->se_name) + 1);
1227 1228 kmem_free(sep, sizeof (zfs_snapentry_t));
1228 1229 break;
1229 1230 }
1230 1231 sep = next;
1231 1232 }
1232 1233 ASSERT(sep != NULL);
1233 1234
1234 1235 mutex_exit(&sdp->sd_lock);
1235 1236 VN_RELE(dvp);
1236 1237
1237 1238 /*
1238 1239 * Dispose of the vnode for the snapshot mount point.
1239 1240 * This is safe to do because once this entry has been removed
1240 1241 * from the AVL tree, it can't be found again, so cannot become
1241 1242 * "active". If we lookup the same name again we will end up
1242 1243 * creating a new vnode.
1243 1244 */
1244 1245 gfs_vop_inactive(vp, cr, ct);
1245 1246 }
1246 1247
1247 1248
1248 1249 /*
1249 1250 * These VP's should never see the light of day. They should always
1250 1251 * be covered.
1251 1252 */
1252 1253 static const fs_operation_def_t zfsctl_tops_snapshot[] = {
1253 1254 VOPNAME_INACTIVE, { .vop_inactive = zfsctl_snapshot_inactive },
1254 1255 NULL, NULL
1255 1256 };
1256 1257
1257 1258 int
1258 1259 zfsctl_lookup_objset(vfs_t *vfsp, uint64_t objsetid, zfsvfs_t **zfsvfsp)
1259 1260 {
1260 1261 zfsvfs_t *zfsvfs = vfsp->vfs_data;
1261 1262 vnode_t *dvp, *vp;
1262 1263 zfsctl_snapdir_t *sdp;
1263 1264 zfsctl_node_t *zcp;
1264 1265 zfs_snapentry_t *sep;
1265 1266 int error;
1266 1267
1267 1268 ASSERT(zfsvfs->z_ctldir != NULL);
1268 1269 error = zfsctl_root_lookup(zfsvfs->z_ctldir, "snapshot", &dvp,
1269 1270 NULL, 0, NULL, kcred, NULL, NULL, NULL);
1270 1271 if (error != 0)
1271 1272 return (error);
1272 1273 sdp = dvp->v_data;
1273 1274
1274 1275 mutex_enter(&sdp->sd_lock);
1275 1276 sep = avl_first(&sdp->sd_snaps);
1276 1277 while (sep != NULL) {
1277 1278 vp = sep->se_root;
1278 1279 zcp = vp->v_data;
1279 1280 if (zcp->zc_id == objsetid)
1280 1281 break;
1281 1282
1282 1283 sep = AVL_NEXT(&sdp->sd_snaps, sep);
1283 1284 }
1284 1285
1285 1286 if (sep != NULL) {
1286 1287 VN_HOLD(vp);
1287 1288 /*
1288 1289 * Return the mounted root rather than the covered mount point.
1289 1290 * Takes the GFS vnode at .zfs/snapshot/<snapshot objsetid>
1290 1291 * and returns the ZFS vnode mounted on top of the GFS node.
1291 1292 * This ZFS vnode is the root of the vfs for objset 'objsetid'.
1292 1293 */
1293 1294 error = traverse(&vp);
1294 1295 if (error == 0) {
1295 1296 if (vp == sep->se_root)
1296 1297 error = SET_ERROR(EINVAL);
1297 1298 else
1298 1299 *zfsvfsp = VTOZ(vp)->z_zfsvfs;
1299 1300 }
1300 1301 mutex_exit(&sdp->sd_lock);
1301 1302 VN_RELE(vp);
1302 1303 } else {
1303 1304 error = SET_ERROR(EINVAL);
1304 1305 mutex_exit(&sdp->sd_lock);
1305 1306 }
1306 1307
1307 1308 VN_RELE(dvp);
1308 1309
1309 1310 return (error);
1310 1311 }
1311 1312
1312 1313 /*
1313 1314 * Unmount any snapshots for the given filesystem. This is called from
1314 1315 * zfs_umount() - if we have a ctldir, then go through and unmount all the
1315 1316 * snapshots.
1316 1317 */
1317 1318 int
1318 1319 zfsctl_umount_snapshots(vfs_t *vfsp, int fflags, cred_t *cr)
1319 1320 {
1320 1321 zfsvfs_t *zfsvfs = vfsp->vfs_data;
1321 1322 vnode_t *dvp;
1322 1323 zfsctl_snapdir_t *sdp;
1323 1324 zfs_snapentry_t *sep, *next;
1324 1325 int error;
1325 1326
1326 1327 ASSERT(zfsvfs->z_ctldir != NULL);
1327 1328 error = zfsctl_root_lookup(zfsvfs->z_ctldir, "snapshot", &dvp,
1328 1329 NULL, 0, NULL, cr, NULL, NULL, NULL);
1329 1330 if (error != 0)
1330 1331 return (error);
1331 1332 sdp = dvp->v_data;
1332 1333
1333 1334 mutex_enter(&sdp->sd_lock);
1334 1335
1335 1336 sep = avl_first(&sdp->sd_snaps);
1336 1337 while (sep != NULL) {
1337 1338 next = AVL_NEXT(&sdp->sd_snaps, sep);
1338 1339
1339 1340 /*
1340 1341 * If this snapshot is not mounted, then it must
1341 1342 * have just been unmounted by somebody else, and
1342 1343 * will be cleaned up by zfsctl_snapdir_inactive().
1343 1344 */
1344 1345 if (vn_ismntpt(sep->se_root)) {
1345 1346 avl_remove(&sdp->sd_snaps, sep);
1346 1347 error = zfsctl_unmount_snap(sep, fflags, cr);
1347 1348 if (error) {
1348 1349 avl_add(&sdp->sd_snaps, sep);
1349 1350 break;
1350 1351 }
1351 1352 }
1352 1353 sep = next;
1353 1354 }
1354 1355
1355 1356 mutex_exit(&sdp->sd_lock);
1356 1357 VN_RELE(dvp);
1357 1358
1358 1359 return (error);
1359 1360 }
↓ open down ↓ |
296 lines elided |
↑ open up ↑ |
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX