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5148 zvol's DKIOCFREE holds zfsdev_state_lock too long
[unleashed.git] / usr / src / uts / common / fs / zfs / zvol.c
blobd9a69470f9484bdde24262c5994e9e0f4ba14d51
1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21 /*
22 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
23 *
24 * Portions Copyright 2010 Robert Milkowski
25 *
26 * Copyright 2011 Nexenta Systems, Inc. All rights reserved.
27 * Copyright (c) 2012, 2014 by Delphix. All rights reserved.
28 * Copyright (c) 2013, Joyent, Inc. All rights reserved.
29 */
30
31 /*
32 * ZFS volume emulation driver.
33 *
34 * Makes a DMU object look like a volume of arbitrary size, up to 2^64 bytes.
35 * Volumes are accessed through the symbolic links named:
36 *
37 * /dev/zvol/dsk/<pool_name>/<dataset_name>
38 * /dev/zvol/rdsk/<pool_name>/<dataset_name>
39 *
40 * These links are created by the /dev filesystem (sdev_zvolops.c).
41 * Volumes are persistent through reboot. No user command needs to be
42 * run before opening and using a device.
43 */
44
45 #include <sys/types.h>
46 #include <sys/param.h>
47 #include <sys/errno.h>
48 #include <sys/uio.h>
49 #include <sys/buf.h>
50 #include <sys/modctl.h>
51 #include <sys/open.h>
52 #include <sys/kmem.h>
53 #include <sys/conf.h>
54 #include <sys/cmn_err.h>
55 #include <sys/stat.h>
56 #include <sys/zap.h>
57 #include <sys/spa.h>
58 #include <sys/spa_impl.h>
59 #include <sys/zio.h>
60 #include <sys/dmu_traverse.h>
61 #include <sys/dnode.h>
62 #include <sys/dsl_dataset.h>
63 #include <sys/dsl_prop.h>
64 #include <sys/dkio.h>
65 #include <sys/efi_partition.h>
66 #include <sys/byteorder.h>
67 #include <sys/pathname.h>
68 #include <sys/ddi.h>
69 #include <sys/sunddi.h>
70 #include <sys/crc32.h>
71 #include <sys/dirent.h>
72 #include <sys/policy.h>
73 #include <sys/fs/zfs.h>
74 #include <sys/zfs_ioctl.h>
75 #include <sys/mkdev.h>
76 #include <sys/zil.h>
77 #include <sys/refcount.h>
78 #include <sys/zfs_znode.h>
79 #include <sys/zfs_rlock.h>
80 #include <sys/vdev_disk.h>
81 #include <sys/vdev_impl.h>
82 #include <sys/vdev_raidz.h>
83 #include <sys/zvol.h>
84 #include <sys/dumphdr.h>
85 #include <sys/zil_impl.h>
86 #include <sys/dbuf.h>
87 #include <sys/dmu_tx.h>
88 #include <sys/zfeature.h>
89 #include <sys/zio_checksum.h>
90
91 #include "zfs_namecheck.h"
92
93 void *zfsdev_state;
94 static char *zvol_tag = "zvol_tag";
95
96 #define ZVOL_DUMPSIZE "dumpsize"
97
98 /*
99 * This lock protects the zfsdev_state structure from being modified
100 * while it's being used, e.g. an open that comes in before a create
101 * finishes. It also protects temporary opens of the dataset so that,
102 * e.g., an open doesn't get a spurious EBUSY.
103 */
104 kmutex_t zfsdev_state_lock;
105 static uint32_t zvol_minors;
106
107 typedef struct zvol_extent {
108 list_node_t ze_node;
109 dva_t ze_dva; /* dva associated with this extent */
110 uint64_t ze_nblks; /* number of blocks in extent */
111 } zvol_extent_t;
112
113 /*
114 * The in-core state of each volume.
115 */
116 typedef struct zvol_state {
117 char zv_name[MAXPATHLEN]; /* pool/dd name */
118 uint64_t zv_volsize; /* amount of space we advertise */
119 uint64_t zv_volblocksize; /* volume block size */
120 minor_t zv_minor; /* minor number */
121 uint8_t zv_min_bs; /* minimum addressable block shift */
122 uint8_t zv_flags; /* readonly, dumpified, etc. */
123 objset_t *zv_objset; /* objset handle */
124 uint32_t zv_open_count[OTYPCNT]; /* open counts */
125 uint32_t zv_total_opens; /* total open count */
126 zilog_t *zv_zilog; /* ZIL handle */
127 list_t zv_extents; /* List of extents for dump */
128 znode_t zv_znode; /* for range locking */
129 dmu_buf_t *zv_dbuf; /* bonus handle */
130 } zvol_state_t;
131
132 /*
133 * zvol specific flags
134 */
135 #define ZVOL_RDONLY 0x1
136 #define ZVOL_DUMPIFIED 0x2
137 #define ZVOL_EXCL 0x4
138 #define ZVOL_WCE 0x8
139
140 /*
141 * zvol maximum transfer in one DMU tx.
142 */
143 int zvol_maxphys = DMU_MAX_ACCESS/2;
144
145 extern int zfs_set_prop_nvlist(const char *, zprop_source_t,
146 nvlist_t *, nvlist_t *);
147 static int zvol_remove_zv(zvol_state_t *);
148 static int zvol_get_data(void *arg, lr_write_t *lr, char *buf, zio_t *zio);
149 static int zvol_dumpify(zvol_state_t *zv);
150 static int zvol_dump_fini(zvol_state_t *zv);
151 static int zvol_dump_init(zvol_state_t *zv, boolean_t resize);
152
153 static void
154 zvol_size_changed(zvol_state_t *zv, uint64_t volsize)
155 {
156 dev_t dev = makedevice(ddi_driver_major(zfs_dip), zv->zv_minor);
157
158 zv->zv_volsize = volsize;
159 VERIFY(ddi_prop_update_int64(dev, zfs_dip,
160 "Size", volsize) == DDI_SUCCESS);
161 VERIFY(ddi_prop_update_int64(dev, zfs_dip,
162 "Nblocks", lbtodb(volsize)) == DDI_SUCCESS);
163
164 /* Notify specfs to invalidate the cached size */
165 spec_size_invalidate(dev, VBLK);
166 spec_size_invalidate(dev, VCHR);
167 }
168
169 int
170 zvol_check_volsize(uint64_t volsize, uint64_t blocksize)
171 {
172 if (volsize == 0)
173 return (SET_ERROR(EINVAL));
174
175 if (volsize % blocksize != 0)
176 return (SET_ERROR(EINVAL));
177
178 #ifdef _ILP32
179 if (volsize - 1 > SPEC_MAXOFFSET_T)
180 return (SET_ERROR(EOVERFLOW));
181 #endif
182 return (0);
183 }
184
185 int
186 zvol_check_volblocksize(uint64_t volblocksize)
187 {
188 if (volblocksize < SPA_MINBLOCKSIZE ||
189 volblocksize > SPA_MAXBLOCKSIZE ||
190 !ISP2(volblocksize))
191 return (SET_ERROR(EDOM));
192
193 return (0);
194 }
195
196 int
197 zvol_get_stats(objset_t *os, nvlist_t *nv)
198 {
199 int error;
200 dmu_object_info_t doi;
201 uint64_t val;
202
203 error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &val);
204 if (error)
205 return (error);
206
207 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_VOLSIZE, val);
208
209 error = dmu_object_info(os, ZVOL_OBJ, &doi);
210
211 if (error == 0) {
212 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_VOLBLOCKSIZE,
213 doi.doi_data_block_size);
214 }
215
216 return (error);
217 }
218
219 static zvol_state_t *
220 zvol_minor_lookup(const char *name)
221 {
222 minor_t minor;
223 zvol_state_t *zv;
224
225 ASSERT(MUTEX_HELD(&zfsdev_state_lock));
226
227 for (minor = 1; minor <= ZFSDEV_MAX_MINOR; minor++) {
228 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL);
229 if (zv == NULL)
230 continue;
231 if (strcmp(zv->zv_name, name) == 0)
232 return (zv);
233 }
234
235 return (NULL);
236 }
237
238 /* extent mapping arg */
239 struct maparg {
240 zvol_state_t *ma_zv;
241 uint64_t ma_blks;
242 };
243
244 /*ARGSUSED*/
245 static int
246 zvol_map_block(spa_t *spa, zilog_t *zilog, const blkptr_t *bp,
247 const zbookmark_phys_t *zb, const dnode_phys_t *dnp, void *arg)
248 {
249 struct maparg *ma = arg;
250 zvol_extent_t *ze;
251 int bs = ma->ma_zv->zv_volblocksize;
252
253 if (BP_IS_HOLE(bp) ||
254 zb->zb_object != ZVOL_OBJ || zb->zb_level != 0)
255 return (0);
256
257 VERIFY(!BP_IS_EMBEDDED(bp));
258
259 VERIFY3U(ma->ma_blks, ==, zb->zb_blkid);
260 ma->ma_blks++;
261
262 /* Abort immediately if we have encountered gang blocks */
263 if (BP_IS_GANG(bp))
264 return (SET_ERROR(EFRAGS));
265
266 /*
267 * See if the block is at the end of the previous extent.
268 */
269 ze = list_tail(&ma->ma_zv->zv_extents);
270 if (ze &&
271 DVA_GET_VDEV(BP_IDENTITY(bp)) == DVA_GET_VDEV(&ze->ze_dva) &&
272 DVA_GET_OFFSET(BP_IDENTITY(bp)) ==
273 DVA_GET_OFFSET(&ze->ze_dva) + ze->ze_nblks * bs) {
274 ze->ze_nblks++;
275 return (0);
276 }
277
278 dprintf_bp(bp, "%s", "next blkptr:");
279
280 /* start a new extent */
281 ze = kmem_zalloc(sizeof (zvol_extent_t), KM_SLEEP);
282 ze->ze_dva = bp->blk_dva[0]; /* structure assignment */
283 ze->ze_nblks = 1;
284 list_insert_tail(&ma->ma_zv->zv_extents, ze);
285 return (0);
286 }
287
288 static void
289 zvol_free_extents(zvol_state_t *zv)
290 {
291 zvol_extent_t *ze;
292
293 while (ze = list_head(&zv->zv_extents)) {
294 list_remove(&zv->zv_extents, ze);
295 kmem_free(ze, sizeof (zvol_extent_t));
296 }
297 }
298
299 static int
300 zvol_get_lbas(zvol_state_t *zv)
301 {
302 objset_t *os = zv->zv_objset;
303 struct maparg ma;
304 int err;
305
306 ma.ma_zv = zv;
307 ma.ma_blks = 0;
308 zvol_free_extents(zv);
309
310 /* commit any in-flight changes before traversing the dataset */
311 txg_wait_synced(dmu_objset_pool(os), 0);
312 err = traverse_dataset(dmu_objset_ds(os), 0,
313 TRAVERSE_PRE | TRAVERSE_PREFETCH_METADATA, zvol_map_block, &ma);
314 if (err || ma.ma_blks != (zv->zv_volsize / zv->zv_volblocksize)) {
315 zvol_free_extents(zv);
316 return (err ? err : EIO);
317 }
318
319 return (0);
320 }
321
322 /* ARGSUSED */
323 void
324 zvol_create_cb(objset_t *os, void *arg, cred_t *cr, dmu_tx_t *tx)
325 {
326 zfs_creat_t *zct = arg;
327 nvlist_t *nvprops = zct->zct_props;
328 int error;
329 uint64_t volblocksize, volsize;
330
331 VERIFY(nvlist_lookup_uint64(nvprops,
332 zfs_prop_to_name(ZFS_PROP_VOLSIZE), &volsize) == 0);
333 if (nvlist_lookup_uint64(nvprops,
334 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), &volblocksize) != 0)
335 volblocksize = zfs_prop_default_numeric(ZFS_PROP_VOLBLOCKSIZE);
336
337 /*
338 * These properties must be removed from the list so the generic
339 * property setting step won't apply to them.
340 */
341 VERIFY(nvlist_remove_all(nvprops,
342 zfs_prop_to_name(ZFS_PROP_VOLSIZE)) == 0);
343 (void) nvlist_remove_all(nvprops,
344 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE));
345
346 error = dmu_object_claim(os, ZVOL_OBJ, DMU_OT_ZVOL, volblocksize,
347 DMU_OT_NONE, 0, tx);
348 ASSERT(error == 0);
349
350 error = zap_create_claim(os, ZVOL_ZAP_OBJ, DMU_OT_ZVOL_PROP,
351 DMU_OT_NONE, 0, tx);
352 ASSERT(error == 0);
353
354 error = zap_update(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize, tx);
355 ASSERT(error == 0);
356 }
357
358 /*
359 * Replay a TX_TRUNCATE ZIL transaction if asked. TX_TRUNCATE is how we
360 * implement DKIOCFREE/free-long-range.
361 */
362 static int
363 zvol_replay_truncate(zvol_state_t *zv, lr_truncate_t *lr, boolean_t byteswap)
364 {
365 uint64_t offset, length;
366
367 if (byteswap)
368 byteswap_uint64_array(lr, sizeof (*lr));
369
370 offset = lr->lr_offset;
371 length = lr->lr_length;
372
373 return (dmu_free_long_range(zv->zv_objset, ZVOL_OBJ, offset, length));
374 }
375
376 /*
377 * Replay a TX_WRITE ZIL transaction that didn't get committed
378 * after a system failure
379 */
380 static int
381 zvol_replay_write(zvol_state_t *zv, lr_write_t *lr, boolean_t byteswap)
382 {
383 objset_t *os = zv->zv_objset;
384 char *data = (char *)(lr + 1); /* data follows lr_write_t */
385 uint64_t offset, length;
386 dmu_tx_t *tx;
387 int error;
388
389 if (byteswap)
390 byteswap_uint64_array(lr, sizeof (*lr));
391
392 offset = lr->lr_offset;
393 length = lr->lr_length;
394
395 /* If it's a dmu_sync() block, write the whole block */
396 if (lr->lr_common.lrc_reclen == sizeof (lr_write_t)) {
397 uint64_t blocksize = BP_GET_LSIZE(&lr->lr_blkptr);
398 if (length < blocksize) {
399 offset -= offset % blocksize;
400 length = blocksize;
401 }
402 }
403
404 tx = dmu_tx_create(os);
405 dmu_tx_hold_write(tx, ZVOL_OBJ, offset, length);
406 error = dmu_tx_assign(tx, TXG_WAIT);
407 if (error) {
408 dmu_tx_abort(tx);
409 } else {
410 dmu_write(os, ZVOL_OBJ, offset, length, data, tx);
411 dmu_tx_commit(tx);
412 }
413
414 return (error);
415 }
416
417 /* ARGSUSED */
418 static int
419 zvol_replay_err(zvol_state_t *zv, lr_t *lr, boolean_t byteswap)
420 {
421 return (SET_ERROR(ENOTSUP));
422 }
423
424 /*
425 * Callback vectors for replaying records.
426 * Only TX_WRITE and TX_TRUNCATE are needed for zvol.
427 */
428 zil_replay_func_t *zvol_replay_vector[TX_MAX_TYPE] = {
429 zvol_replay_err, /* 0 no such transaction type */
430 zvol_replay_err, /* TX_CREATE */
431 zvol_replay_err, /* TX_MKDIR */
432 zvol_replay_err, /* TX_MKXATTR */
433 zvol_replay_err, /* TX_SYMLINK */
434 zvol_replay_err, /* TX_REMOVE */
435 zvol_replay_err, /* TX_RMDIR */
436 zvol_replay_err, /* TX_LINK */
437 zvol_replay_err, /* TX_RENAME */
438 zvol_replay_write, /* TX_WRITE */
439 zvol_replay_truncate, /* TX_TRUNCATE */
440 zvol_replay_err, /* TX_SETATTR */
441 zvol_replay_err, /* TX_ACL */
442 zvol_replay_err, /* TX_CREATE_ACL */
443 zvol_replay_err, /* TX_CREATE_ATTR */
444 zvol_replay_err, /* TX_CREATE_ACL_ATTR */
445 zvol_replay_err, /* TX_MKDIR_ACL */
446 zvol_replay_err, /* TX_MKDIR_ATTR */
447 zvol_replay_err, /* TX_MKDIR_ACL_ATTR */
448 zvol_replay_err, /* TX_WRITE2 */
449 };
450
451 int
452 zvol_name2minor(const char *name, minor_t *minor)
453 {
454 zvol_state_t *zv;
455
456 mutex_enter(&zfsdev_state_lock);
457 zv = zvol_minor_lookup(name);
458 if (minor && zv)
459 *minor = zv->zv_minor;
460 mutex_exit(&zfsdev_state_lock);
461 return (zv ? 0 : -1);
462 }
463
464 /*
465 * Create a minor node (plus a whole lot more) for the specified volume.
466 */
467 int
468 zvol_create_minor(const char *name)
469 {
470 zfs_soft_state_t *zs;
471 zvol_state_t *zv;
472 objset_t *os;
473 dmu_object_info_t doi;
474 minor_t minor = 0;
475 char chrbuf[30], blkbuf[30];
476 int error;
477
478 mutex_enter(&zfsdev_state_lock);
479
480 if (zvol_minor_lookup(name) != NULL) {
481 mutex_exit(&zfsdev_state_lock);
482 return (SET_ERROR(EEXIST));
483 }
484
485 /* lie and say we're read-only */
486 error = dmu_objset_own(name, DMU_OST_ZVOL, B_TRUE, FTAG, &os);
487
488 if (error) {
489 mutex_exit(&zfsdev_state_lock);
490 return (error);
491 }
492
493 if ((minor = zfsdev_minor_alloc()) == 0) {
494 dmu_objset_disown(os, FTAG);
495 mutex_exit(&zfsdev_state_lock);
496 return (SET_ERROR(ENXIO));
497 }
498
499 if (ddi_soft_state_zalloc(zfsdev_state, minor) != DDI_SUCCESS) {
500 dmu_objset_disown(os, FTAG);
501 mutex_exit(&zfsdev_state_lock);
502 return (SET_ERROR(EAGAIN));
503 }
504 (void) ddi_prop_update_string(minor, zfs_dip, ZVOL_PROP_NAME,
505 (char *)name);
506
507 (void) snprintf(chrbuf, sizeof (chrbuf), "%u,raw", minor);
508
509 if (ddi_create_minor_node(zfs_dip, chrbuf, S_IFCHR,
510 minor, DDI_PSEUDO, 0) == DDI_FAILURE) {
511 ddi_soft_state_free(zfsdev_state, minor);
512 dmu_objset_disown(os, FTAG);
513 mutex_exit(&zfsdev_state_lock);
514 return (SET_ERROR(EAGAIN));
515 }
516
517 (void) snprintf(blkbuf, sizeof (blkbuf), "%u", minor);
518
519 if (ddi_create_minor_node(zfs_dip, blkbuf, S_IFBLK,
520 minor, DDI_PSEUDO, 0) == DDI_FAILURE) {
521 ddi_remove_minor_node(zfs_dip, chrbuf);
522 ddi_soft_state_free(zfsdev_state, minor);
523 dmu_objset_disown(os, FTAG);
524 mutex_exit(&zfsdev_state_lock);
525 return (SET_ERROR(EAGAIN));
526 }
527
528 zs = ddi_get_soft_state(zfsdev_state, minor);
529 zs->zss_type = ZSST_ZVOL;
530 zv = zs->zss_data = kmem_zalloc(sizeof (zvol_state_t), KM_SLEEP);
531 (void) strlcpy(zv->zv_name, name, MAXPATHLEN);
532 zv->zv_min_bs = DEV_BSHIFT;
533 zv->zv_minor = minor;
534 zv->zv_objset = os;
535 if (dmu_objset_is_snapshot(os) || !spa_writeable(dmu_objset_spa(os)))
536 zv->zv_flags |= ZVOL_RDONLY;
537 mutex_init(&zv->zv_znode.z_range_lock, NULL, MUTEX_DEFAULT, NULL);
538 avl_create(&zv->zv_znode.z_range_avl, zfs_range_compare,
539 sizeof (rl_t), offsetof(rl_t, r_node));
540 list_create(&zv->zv_extents, sizeof (zvol_extent_t),
541 offsetof(zvol_extent_t, ze_node));
542 /* get and cache the blocksize */
543 error = dmu_object_info(os, ZVOL_OBJ, &doi);
544 ASSERT(error == 0);
545 zv->zv_volblocksize = doi.doi_data_block_size;
546
547 if (spa_writeable(dmu_objset_spa(os))) {
548 if (zil_replay_disable)
549 zil_destroy(dmu_objset_zil(os), B_FALSE);
550 else
551 zil_replay(os, zv, zvol_replay_vector);
552 }
553 dmu_objset_disown(os, FTAG);
554 zv->zv_objset = NULL;
555
556 zvol_minors++;
557
558 mutex_exit(&zfsdev_state_lock);
559
560 return (0);
561 }
562
563 /*
564 * Remove minor node for the specified volume.
565 */
566 static int
567 zvol_remove_zv(zvol_state_t *zv)
568 {
569 char nmbuf[20];
570 minor_t minor = zv->zv_minor;
571
572 ASSERT(MUTEX_HELD(&zfsdev_state_lock));
573 if (zv->zv_total_opens != 0)
574 return (SET_ERROR(EBUSY));
575
576 (void) snprintf(nmbuf, sizeof (nmbuf), "%u,raw", minor);
577 ddi_remove_minor_node(zfs_dip, nmbuf);
578
579 (void) snprintf(nmbuf, sizeof (nmbuf), "%u", minor);
580 ddi_remove_minor_node(zfs_dip, nmbuf);
581
582 avl_destroy(&zv->zv_znode.z_range_avl);
583 mutex_destroy(&zv->zv_znode.z_range_lock);
584
585 kmem_free(zv, sizeof (zvol_state_t));
586
587 ddi_soft_state_free(zfsdev_state, minor);
588
589 zvol_minors--;
590 return (0);
591 }
592
593 int
594 zvol_remove_minor(const char *name)
595 {
596 zvol_state_t *zv;
597 int rc;
598
599 mutex_enter(&zfsdev_state_lock);
600 if ((zv = zvol_minor_lookup(name)) == NULL) {
601 mutex_exit(&zfsdev_state_lock);
602 return (SET_ERROR(ENXIO));
603 }
604 rc = zvol_remove_zv(zv);
605 mutex_exit(&zfsdev_state_lock);
606 return (rc);
607 }
608
609 int
610 zvol_first_open(zvol_state_t *zv)
611 {
612 objset_t *os;
613 uint64_t volsize;
614 int error;
615 uint64_t readonly;
616
617 /* lie and say we're read-only */
618 error = dmu_objset_own(zv->zv_name, DMU_OST_ZVOL, B_TRUE,
619 zvol_tag, &os);
620 if (error)
621 return (error);
622
623 zv->zv_objset = os;
624 error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize);
625 if (error) {
626 ASSERT(error == 0);
627 dmu_objset_disown(os, zvol_tag);
628 return (error);
629 }
630
631 error = dmu_bonus_hold(os, ZVOL_OBJ, zvol_tag, &zv->zv_dbuf);
632 if (error) {
633 dmu_objset_disown(os, zvol_tag);
634 return (error);
635 }
636
637 zvol_size_changed(zv, volsize);
638 zv->zv_zilog = zil_open(os, zvol_get_data);
639
640 VERIFY(dsl_prop_get_integer(zv->zv_name, "readonly", &readonly,
641 NULL) == 0);
642 if (readonly || dmu_objset_is_snapshot(os) ||
643 !spa_writeable(dmu_objset_spa(os)))
644 zv->zv_flags |= ZVOL_RDONLY;
645 else
646 zv->zv_flags &= ~ZVOL_RDONLY;
647 return (error);
648 }
649
650 void
651 zvol_last_close(zvol_state_t *zv)
652 {
653 zil_close(zv->zv_zilog);
654 zv->zv_zilog = NULL;
655
656 dmu_buf_rele(zv->zv_dbuf, zvol_tag);
657 zv->zv_dbuf = NULL;
658
659 /*
660 * Evict cached data
661 */
662 if (dsl_dataset_is_dirty(dmu_objset_ds(zv->zv_objset)) &&
663 !(zv->zv_flags & ZVOL_RDONLY))
664 txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0);
665 dmu_objset_evict_dbufs(zv->zv_objset);
666
667 dmu_objset_disown(zv->zv_objset, zvol_tag);
668 zv->zv_objset = NULL;
669 }
670
671 int
672 zvol_prealloc(zvol_state_t *zv)
673 {
674 objset_t *os = zv->zv_objset;
675 dmu_tx_t *tx;
676 uint64_t refd, avail, usedobjs, availobjs;
677 uint64_t resid = zv->zv_volsize;
678 uint64_t off = 0;
679
680 /* Check the space usage before attempting to allocate the space */
681 dmu_objset_space(os, &refd, &avail, &usedobjs, &availobjs);
682 if (avail < zv->zv_volsize)
683 return (SET_ERROR(ENOSPC));
684
685 /* Free old extents if they exist */
686 zvol_free_extents(zv);
687
688 while (resid != 0) {
689 int error;
690 uint64_t bytes = MIN(resid, SPA_MAXBLOCKSIZE);
691
692 tx = dmu_tx_create(os);
693 dmu_tx_hold_write(tx, ZVOL_OBJ, off, bytes);
694 error = dmu_tx_assign(tx, TXG_WAIT);
695 if (error) {
696 dmu_tx_abort(tx);
697 (void) dmu_free_long_range(os, ZVOL_OBJ, 0, off);
698 return (error);
699 }
700 dmu_prealloc(os, ZVOL_OBJ, off, bytes, tx);
701 dmu_tx_commit(tx);
702 off += bytes;
703 resid -= bytes;
704 }
705 txg_wait_synced(dmu_objset_pool(os), 0);
706
707 return (0);
708 }
709
710 static int
711 zvol_update_volsize(objset_t *os, uint64_t volsize)
712 {
713 dmu_tx_t *tx;
714 int error;
715
716 ASSERT(MUTEX_HELD(&zfsdev_state_lock));
717
718 tx = dmu_tx_create(os);
719 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL);
720 dmu_tx_mark_netfree(tx);
721 error = dmu_tx_assign(tx, TXG_WAIT);
722 if (error) {
723 dmu_tx_abort(tx);
724 return (error);
725 }
726
727 error = zap_update(os, ZVOL_ZAP_OBJ, "size", 8, 1,
728 &volsize, tx);
729 dmu_tx_commit(tx);
730
731 if (error == 0)
732 error = dmu_free_long_range(os,
733 ZVOL_OBJ, volsize, DMU_OBJECT_END);
734 return (error);
735 }
736
737 void
738 zvol_remove_minors(const char *name)
739 {
740 zvol_state_t *zv;
741 char *namebuf;
742 minor_t minor;
743
744 namebuf = kmem_zalloc(strlen(name) + 2, KM_SLEEP);
745 (void) strncpy(namebuf, name, strlen(name));
746 (void) strcat(namebuf, "/");
747 mutex_enter(&zfsdev_state_lock);
748 for (minor = 1; minor <= ZFSDEV_MAX_MINOR; minor++) {
749
750 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL);
751 if (zv == NULL)
752 continue;
753 if (strncmp(namebuf, zv->zv_name, strlen(namebuf)) == 0)
754 (void) zvol_remove_zv(zv);
755 }
756 kmem_free(namebuf, strlen(name) + 2);
757
758 mutex_exit(&zfsdev_state_lock);
759 }
760
761 static int
762 zvol_update_live_volsize(zvol_state_t *zv, uint64_t volsize)
763 {
764 uint64_t old_volsize = 0ULL;
765 int error = 0;
766
767 ASSERT(MUTEX_HELD(&zfsdev_state_lock));
768
769 /*
770 * Reinitialize the dump area to the new size. If we
771 * failed to resize the dump area then restore it back to
772 * its original size. We must set the new volsize prior
773 * to calling dumpvp_resize() to ensure that the devices'
774 * size(9P) is not visible by the dump subsystem.
775 */
776 old_volsize = zv->zv_volsize;
777 zvol_size_changed(zv, volsize);
778
779 if (zv->zv_flags & ZVOL_DUMPIFIED) {
780 if ((error = zvol_dumpify(zv)) != 0 ||
781 (error = dumpvp_resize()) != 0) {
782 int dumpify_error;
783
784 (void) zvol_update_volsize(zv->zv_objset, old_volsize);
785 zvol_size_changed(zv, old_volsize);
786 dumpify_error = zvol_dumpify(zv);
787 error = dumpify_error ? dumpify_error : error;
788 }
789 }
790
791 /*
792 * Generate a LUN expansion event.
793 */
794 if (error == 0) {
795 sysevent_id_t eid;
796 nvlist_t *attr;
797 char *physpath = kmem_zalloc(MAXPATHLEN, KM_SLEEP);
798
799 (void) snprintf(physpath, MAXPATHLEN, "%s%u", ZVOL_PSEUDO_DEV,
800 zv->zv_minor);
801
802 VERIFY(nvlist_alloc(&attr, NV_UNIQUE_NAME, KM_SLEEP) == 0);
803 VERIFY(nvlist_add_string(attr, DEV_PHYS_PATH, physpath) == 0);
804
805 (void) ddi_log_sysevent(zfs_dip, SUNW_VENDOR, EC_DEV_STATUS,
806 ESC_DEV_DLE, attr, &eid, DDI_SLEEP);
807
808 nvlist_free(attr);
809 kmem_free(physpath, MAXPATHLEN);
810 }
811 return (error);
812 }
813
814 int
815 zvol_set_volsize(const char *name, uint64_t volsize)
816 {
817 zvol_state_t *zv = NULL;
818 objset_t *os;
819 int error;
820 dmu_object_info_t doi;
821 uint64_t readonly;
822 boolean_t owned = B_FALSE;
823
824 error = dsl_prop_get_integer(name,
825 zfs_prop_to_name(ZFS_PROP_READONLY), &readonly, NULL);
826 if (error != 0)
827 return (error);
828 if (readonly)
829 return (SET_ERROR(EROFS));
830
831 mutex_enter(&zfsdev_state_lock);
832 zv = zvol_minor_lookup(name);
833
834 if (zv == NULL || zv->zv_objset == NULL) {
835 if ((error = dmu_objset_own(name, DMU_OST_ZVOL, B_FALSE,
836 FTAG, &os)) != 0) {
837 mutex_exit(&zfsdev_state_lock);
838 return (error);
839 }
840 owned = B_TRUE;
841 if (zv != NULL)
842 zv->zv_objset = os;
843 } else {
844 os = zv->zv_objset;
845 }
846
847 if ((error = dmu_object_info(os, ZVOL_OBJ, &doi)) != 0 ||
848 (error = zvol_check_volsize(volsize, doi.doi_data_block_size)) != 0)
849 goto out;
850
851 error = zvol_update_volsize(os, volsize);
852
853 if (error == 0 && zv != NULL)
854 error = zvol_update_live_volsize(zv, volsize);
855 out:
856 if (owned) {
857 dmu_objset_disown(os, FTAG);
858 if (zv != NULL)
859 zv->zv_objset = NULL;
860 }
861 mutex_exit(&zfsdev_state_lock);
862 return (error);
863 }
864
865 /*ARGSUSED*/
866 int
867 zvol_open(dev_t *devp, int flag, int otyp, cred_t *cr)
868 {
869 zvol_state_t *zv;
870 int err = 0;
871
872 mutex_enter(&zfsdev_state_lock);
873
874 zv = zfsdev_get_soft_state(getminor(*devp), ZSST_ZVOL);
875 if (zv == NULL) {
876 mutex_exit(&zfsdev_state_lock);
877 return (SET_ERROR(ENXIO));
878 }
879
880 if (zv->zv_total_opens == 0)
881 err = zvol_first_open(zv);
882 if (err) {
883 mutex_exit(&zfsdev_state_lock);
884 return (err);
885 }
886 if ((flag & FWRITE) && (zv->zv_flags & ZVOL_RDONLY)) {
887 err = SET_ERROR(EROFS);
888 goto out;
889 }
890 if (zv->zv_flags & ZVOL_EXCL) {
891 err = SET_ERROR(EBUSY);
892 goto out;
893 }
894 if (flag & FEXCL) {
895 if (zv->zv_total_opens != 0) {
896 err = SET_ERROR(EBUSY);
897 goto out;
898 }
899 zv->zv_flags |= ZVOL_EXCL;
900 }
901
902 if (zv->zv_open_count[otyp] == 0 || otyp == OTYP_LYR) {
903 zv->zv_open_count[otyp]++;
904 zv->zv_total_opens++;
905 }
906 mutex_exit(&zfsdev_state_lock);
907
908 return (err);
909 out:
910 if (zv->zv_total_opens == 0)
911 zvol_last_close(zv);
912 mutex_exit(&zfsdev_state_lock);
913 return (err);
914 }
915
916 /*ARGSUSED*/
917 int
918 zvol_close(dev_t dev, int flag, int otyp, cred_t *cr)
919 {
920 minor_t minor = getminor(dev);
921 zvol_state_t *zv;
922 int error = 0;
923
924 mutex_enter(&zfsdev_state_lock);
925
926 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL);
927 if (zv == NULL) {
928 mutex_exit(&zfsdev_state_lock);
929 return (SET_ERROR(ENXIO));
930 }
931
932 if (zv->zv_flags & ZVOL_EXCL) {
933 ASSERT(zv->zv_total_opens == 1);
934 zv->zv_flags &= ~ZVOL_EXCL;
935 }
936
937 /*
938 * If the open count is zero, this is a spurious close.
939 * That indicates a bug in the kernel / DDI framework.
940 */
941 ASSERT(zv->zv_open_count[otyp] != 0);
942 ASSERT(zv->zv_total_opens != 0);
943
944 /*
945 * You may get multiple opens, but only one close.
946 */
947 zv->zv_open_count[otyp]--;
948 zv->zv_total_opens--;
949
950 if (zv->zv_total_opens == 0)
951 zvol_last_close(zv);
952
953 mutex_exit(&zfsdev_state_lock);
954 return (error);
955 }
956
957 static void
958 zvol_get_done(zgd_t *zgd, int error)
959 {
960 if (zgd->zgd_db)
961 dmu_buf_rele(zgd->zgd_db, zgd);
962
963 zfs_range_unlock(zgd->zgd_rl);
964
965 if (error == 0 && zgd->zgd_bp)
966 zil_add_block(zgd->zgd_zilog, zgd->zgd_bp);
967
968 kmem_free(zgd, sizeof (zgd_t));
969 }
970
971 /*
972 * Get data to generate a TX_WRITE intent log record.
973 */
974 static int
975 zvol_get_data(void *arg, lr_write_t *lr, char *buf, zio_t *zio)
976 {
977 zvol_state_t *zv = arg;
978 objset_t *os = zv->zv_objset;
979 uint64_t object = ZVOL_OBJ;
980 uint64_t offset = lr->lr_offset;
981 uint64_t size = lr->lr_length; /* length of user data */
982 blkptr_t *bp = &lr->lr_blkptr;
983 dmu_buf_t *db;
984 zgd_t *zgd;
985 int error;
986
987 ASSERT(zio != NULL);
988 ASSERT(size != 0);
989
990 zgd = kmem_zalloc(sizeof (zgd_t), KM_SLEEP);
991 zgd->zgd_zilog = zv->zv_zilog;
992 zgd->zgd_rl = zfs_range_lock(&zv->zv_znode, offset, size, RL_READER);
993
994 /*
995 * Write records come in two flavors: immediate and indirect.
996 * For small writes it's cheaper to store the data with the
997 * log record (immediate); for large writes it's cheaper to
998 * sync the data and get a pointer to it (indirect) so that
999 * we don't have to write the data twice.
1000 */
1001 if (buf != NULL) { /* immediate write */
1002 error = dmu_read(os, object, offset, size, buf,
1003 DMU_READ_NO_PREFETCH);
1004 } else {
1005 size = zv->zv_volblocksize;
1006 offset = P2ALIGN(offset, size);
1007 error = dmu_buf_hold(os, object, offset, zgd, &db,
1008 DMU_READ_NO_PREFETCH);
1009 if (error == 0) {
1010 blkptr_t *obp = dmu_buf_get_blkptr(db);
1011 if (obp) {
1012 ASSERT(BP_IS_HOLE(bp));
1013 *bp = *obp;
1014 }
1015
1016 zgd->zgd_db = db;
1017 zgd->zgd_bp = bp;
1018
1019 ASSERT(db->db_offset == offset);
1020 ASSERT(db->db_size == size);
1021
1022 error = dmu_sync(zio, lr->lr_common.lrc_txg,
1023 zvol_get_done, zgd);
1024
1025 if (error == 0)
1026 return (0);
1027 }
1028 }
1029
1030 zvol_get_done(zgd, error);
1031
1032 return (error);
1033 }
1034
1035 /*
1036 * zvol_log_write() handles synchronous writes using TX_WRITE ZIL transactions.
1037 *
1038 * We store data in the log buffers if it's small enough.
1039 * Otherwise we will later flush the data out via dmu_sync().
1040 */
1041 ssize_t zvol_immediate_write_sz = 32768;
1042
1043 static void
1044 zvol_log_write(zvol_state_t *zv, dmu_tx_t *tx, offset_t off, ssize_t resid,
1045 boolean_t sync)
1046 {
1047 uint32_t blocksize = zv->zv_volblocksize;
1048 zilog_t *zilog = zv->zv_zilog;
1049 boolean_t slogging;
1050 ssize_t immediate_write_sz;
1051
1052 if (zil_replaying(zilog, tx))
1053 return;
1054
1055 immediate_write_sz = (zilog->zl_logbias == ZFS_LOGBIAS_THROUGHPUT)
1056 ? 0 : zvol_immediate_write_sz;
1057
1058 slogging = spa_has_slogs(zilog->zl_spa) &&
1059 (zilog->zl_logbias == ZFS_LOGBIAS_LATENCY);
1060
1061 while (resid) {
1062 itx_t *itx;
1063 lr_write_t *lr;
1064 ssize_t len;
1065 itx_wr_state_t write_state;
1066
1067 /*
1068 * Unlike zfs_log_write() we can be called with
1069 * upto DMU_MAX_ACCESS/2 (5MB) writes.
1070 */
1071 if (blocksize > immediate_write_sz && !slogging &&
1072 resid >= blocksize && off % blocksize == 0) {
1073 write_state = WR_INDIRECT; /* uses dmu_sync */
1074 len = blocksize;
1075 } else if (sync) {
1076 write_state = WR_COPIED;
1077 len = MIN(ZIL_MAX_LOG_DATA, resid);
1078 } else {
1079 write_state = WR_NEED_COPY;
1080 len = MIN(ZIL_MAX_LOG_DATA, resid);
1081 }
1082
1083 itx = zil_itx_create(TX_WRITE, sizeof (*lr) +
1084 (write_state == WR_COPIED ? len : 0));
1085 lr = (lr_write_t *)&itx->itx_lr;
1086 if (write_state == WR_COPIED && dmu_read(zv->zv_objset,
1087 ZVOL_OBJ, off, len, lr + 1, DMU_READ_NO_PREFETCH) != 0) {
1088 zil_itx_destroy(itx);
1089 itx = zil_itx_create(TX_WRITE, sizeof (*lr));
1090 lr = (lr_write_t *)&itx->itx_lr;
1091 write_state = WR_NEED_COPY;
1092 }
1093
1094 itx->itx_wr_state = write_state;
1095 if (write_state == WR_NEED_COPY)
1096 itx->itx_sod += len;
1097 lr->lr_foid = ZVOL_OBJ;
1098 lr->lr_offset = off;
1099 lr->lr_length = len;
1100 lr->lr_blkoff = 0;
1101 BP_ZERO(&lr->lr_blkptr);
1102
1103 itx->itx_private = zv;
1104 itx->itx_sync = sync;
1105
1106 zil_itx_assign(zilog, itx, tx);
1107
1108 off += len;
1109 resid -= len;
1110 }
1111 }
1112
1113 static int
1114 zvol_dumpio_vdev(vdev_t *vd, void *addr, uint64_t offset, uint64_t origoffset,
1115 uint64_t size, boolean_t doread, boolean_t isdump)
1116 {
1117 vdev_disk_t *dvd;
1118 int c;
1119 int numerrors = 0;
1120
1121 if (vd->vdev_ops == &vdev_mirror_ops ||
1122 vd->vdev_ops == &vdev_replacing_ops ||
1123 vd->vdev_ops == &vdev_spare_ops) {
1124 for (c = 0; c < vd->vdev_children; c++) {
1125 int err = zvol_dumpio_vdev(vd->vdev_child[c],
1126 addr, offset, origoffset, size, doread, isdump);
1127 if (err != 0) {
1128 numerrors++;
1129 } else if (doread) {
1130 break;
1131 }
1132 }
1133 }
1134
1135 if (!vd->vdev_ops->vdev_op_leaf && vd->vdev_ops != &vdev_raidz_ops)
1136 return (numerrors < vd->vdev_children ? 0 : EIO);
1137
1138 if (doread && !vdev_readable(vd))
1139 return (SET_ERROR(EIO));
1140 else if (!doread && !vdev_writeable(vd))
1141 return (SET_ERROR(EIO));
1142
1143 if (vd->vdev_ops == &vdev_raidz_ops) {
1144 return (vdev_raidz_physio(vd,
1145 addr, size, offset, origoffset, doread, isdump));
1146 }
1147
1148 offset += VDEV_LABEL_START_SIZE;
1149
1150 if (ddi_in_panic() || isdump) {
1151 ASSERT(!doread);
1152 if (doread)
1153 return (SET_ERROR(EIO));
1154 dvd = vd->vdev_tsd;
1155 ASSERT3P(dvd, !=, NULL);
1156 return (ldi_dump(dvd->vd_lh, addr, lbtodb(offset),
1157 lbtodb(size)));
1158 } else {
1159 dvd = vd->vdev_tsd;
1160 ASSERT3P(dvd, !=, NULL);
1161 return (vdev_disk_ldi_physio(dvd->vd_lh, addr, size,
1162 offset, doread ? B_READ : B_WRITE));
1163 }
1164 }
1165
1166 static int
1167 zvol_dumpio(zvol_state_t *zv, void *addr, uint64_t offset, uint64_t size,
1168 boolean_t doread, boolean_t isdump)
1169 {
1170 vdev_t *vd;
1171 int error;
1172 zvol_extent_t *ze;
1173 spa_t *spa = dmu_objset_spa(zv->zv_objset);
1174
1175 /* Must be sector aligned, and not stradle a block boundary. */
1176 if (P2PHASE(offset, DEV_BSIZE) || P2PHASE(size, DEV_BSIZE) ||
1177 P2BOUNDARY(offset, size, zv->zv_volblocksize)) {
1178 return (SET_ERROR(EINVAL));
1179 }
1180 ASSERT(size <= zv->zv_volblocksize);
1181
1182 /* Locate the extent this belongs to */
1183 ze = list_head(&zv->zv_extents);
1184 while (offset >= ze->ze_nblks * zv->zv_volblocksize) {
1185 offset -= ze->ze_nblks * zv->zv_volblocksize;
1186 ze = list_next(&zv->zv_extents, ze);
1187 }
1188
1189 if (ze == NULL)
1190 return (SET_ERROR(EINVAL));
1191
1192 if (!ddi_in_panic())
1193 spa_config_enter(spa, SCL_STATE, FTAG, RW_READER);
1194
1195 vd = vdev_lookup_top(spa, DVA_GET_VDEV(&ze->ze_dva));
1196 offset += DVA_GET_OFFSET(&ze->ze_dva);
1197 error = zvol_dumpio_vdev(vd, addr, offset, DVA_GET_OFFSET(&ze->ze_dva),
1198 size, doread, isdump);
1199
1200 if (!ddi_in_panic())
1201 spa_config_exit(spa, SCL_STATE, FTAG);
1202
1203 return (error);
1204 }
1205
1206 int
1207 zvol_strategy(buf_t *bp)
1208 {
1209 zfs_soft_state_t *zs = NULL;
1210 zvol_state_t *zv;
1211 uint64_t off, volsize;
1212 size_t resid;
1213 char *addr;
1214 objset_t *os;
1215 rl_t *rl;
1216 int error = 0;
1217 boolean_t doread = bp->b_flags & B_READ;
1218 boolean_t is_dumpified;
1219 boolean_t sync;
1220
1221 if (getminor(bp->b_edev) == 0) {
1222 error = SET_ERROR(EINVAL);
1223 } else {
1224 zs = ddi_get_soft_state(zfsdev_state, getminor(bp->b_edev));
1225 if (zs == NULL)
1226 error = SET_ERROR(ENXIO);
1227 else if (zs->zss_type != ZSST_ZVOL)
1228 error = SET_ERROR(EINVAL);
1229 }
1230
1231 if (error) {
1232 bioerror(bp, error);
1233 biodone(bp);
1234 return (0);
1235 }
1236
1237 zv = zs->zss_data;
1238
1239 if (!(bp->b_flags & B_READ) && (zv->zv_flags & ZVOL_RDONLY)) {
1240 bioerror(bp, EROFS);
1241 biodone(bp);
1242 return (0);
1243 }
1244
1245 off = ldbtob(bp->b_blkno);
1246 volsize = zv->zv_volsize;
1247
1248 os = zv->zv_objset;
1249 ASSERT(os != NULL);
1250
1251 bp_mapin(bp);
1252 addr = bp->b_un.b_addr;
1253 resid = bp->b_bcount;
1254
1255 if (resid > 0 && (off < 0 || off >= volsize)) {
1256 bioerror(bp, EIO);
1257 biodone(bp);
1258 return (0);
1259 }
1260
1261 is_dumpified = zv->zv_flags & ZVOL_DUMPIFIED;
1262 sync = ((!(bp->b_flags & B_ASYNC) &&
1263 !(zv->zv_flags & ZVOL_WCE)) ||
1264 (zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS)) &&
1265 !doread && !is_dumpified;
1266
1267 /*
1268 * There must be no buffer changes when doing a dmu_sync() because
1269 * we can't change the data whilst calculating the checksum.
1270 */
1271 rl = zfs_range_lock(&zv->zv_znode, off, resid,
1272 doread ? RL_READER : RL_WRITER);
1273
1274 while (resid != 0 && off < volsize) {
1275 size_t size = MIN(resid, zvol_maxphys);
1276 if (is_dumpified) {
1277 size = MIN(size, P2END(off, zv->zv_volblocksize) - off);
1278 error = zvol_dumpio(zv, addr, off, size,
1279 doread, B_FALSE);
1280 } else if (doread) {
1281 error = dmu_read(os, ZVOL_OBJ, off, size, addr,
1282 DMU_READ_PREFETCH);
1283 } else {
1284 dmu_tx_t *tx = dmu_tx_create(os);
1285 dmu_tx_hold_write(tx, ZVOL_OBJ, off, size);
1286 error = dmu_tx_assign(tx, TXG_WAIT);
1287 if (error) {
1288 dmu_tx_abort(tx);
1289 } else {
1290 dmu_write(os, ZVOL_OBJ, off, size, addr, tx);
1291 zvol_log_write(zv, tx, off, size, sync);
1292 dmu_tx_commit(tx);
1293 }
1294 }
1295 if (error) {
1296 /* convert checksum errors into IO errors */
1297 if (error == ECKSUM)
1298 error = SET_ERROR(EIO);
1299 break;
1300 }
1301 off += size;
1302 addr += size;
1303 resid -= size;
1304 }
1305 zfs_range_unlock(rl);
1306
1307 if ((bp->b_resid = resid) == bp->b_bcount)
1308 bioerror(bp, off > volsize ? EINVAL : error);
1309
1310 if (sync)
1311 zil_commit(zv->zv_zilog, ZVOL_OBJ);
1312 biodone(bp);
1313
1314 return (0);
1315 }
1316
1317 /*
1318 * Set the buffer count to the zvol maximum transfer.
1319 * Using our own routine instead of the default minphys()
1320 * means that for larger writes we write bigger buffers on X86
1321 * (128K instead of 56K) and flush the disk write cache less often
1322 * (every zvol_maxphys - currently 1MB) instead of minphys (currently
1323 * 56K on X86 and 128K on sparc).
1324 */
1325 void
1326 zvol_minphys(struct buf *bp)
1327 {
1328 if (bp->b_bcount > zvol_maxphys)
1329 bp->b_bcount = zvol_maxphys;
1330 }
1331
1332 int
1333 zvol_dump(dev_t dev, caddr_t addr, daddr_t blkno, int nblocks)
1334 {
1335 minor_t minor = getminor(dev);
1336 zvol_state_t *zv;
1337 int error = 0;
1338 uint64_t size;
1339 uint64_t boff;
1340 uint64_t resid;
1341
1342 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL);
1343 if (zv == NULL)
1344 return (SET_ERROR(ENXIO));
1345
1346 if ((zv->zv_flags & ZVOL_DUMPIFIED) == 0)
1347 return (SET_ERROR(EINVAL));
1348
1349 boff = ldbtob(blkno);
1350 resid = ldbtob(nblocks);
1351
1352 VERIFY3U(boff + resid, <=, zv->zv_volsize);
1353
1354 while (resid) {
1355 size = MIN(resid, P2END(boff, zv->zv_volblocksize) - boff);
1356 error = zvol_dumpio(zv, addr, boff, size, B_FALSE, B_TRUE);
1357 if (error)
1358 break;
1359 boff += size;
1360 addr += size;
1361 resid -= size;
1362 }
1363
1364 return (error);
1365 }
1366
1367 /*ARGSUSED*/
1368 int
1369 zvol_read(dev_t dev, uio_t *uio, cred_t *cr)
1370 {
1371 minor_t minor = getminor(dev);
1372 zvol_state_t *zv;
1373 uint64_t volsize;
1374 rl_t *rl;
1375 int error = 0;
1376
1377 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL);
1378 if (zv == NULL)
1379 return (SET_ERROR(ENXIO));
1380
1381 volsize = zv->zv_volsize;
1382 if (uio->uio_resid > 0 &&
1383 (uio->uio_loffset < 0 || uio->uio_loffset >= volsize))
1384 return (SET_ERROR(EIO));
1385
1386 if (zv->zv_flags & ZVOL_DUMPIFIED) {
1387 error = physio(zvol_strategy, NULL, dev, B_READ,
1388 zvol_minphys, uio);
1389 return (error);
1390 }
1391
1392 rl = zfs_range_lock(&zv->zv_znode, uio->uio_loffset, uio->uio_resid,
1393 RL_READER);
1394 while (uio->uio_resid > 0 && uio->uio_loffset < volsize) {
1395 uint64_t bytes = MIN(uio->uio_resid, DMU_MAX_ACCESS >> 1);
1396
1397 /* don't read past the end */
1398 if (bytes > volsize - uio->uio_loffset)
1399 bytes = volsize - uio->uio_loffset;
1400
1401 error = dmu_read_uio(zv->zv_objset, ZVOL_OBJ, uio, bytes);
1402 if (error) {
1403 /* convert checksum errors into IO errors */
1404 if (error == ECKSUM)
1405 error = SET_ERROR(EIO);
1406 break;
1407 }
1408 }
1409 zfs_range_unlock(rl);
1410 return (error);
1411 }
1412
1413 /*ARGSUSED*/
1414 int
1415 zvol_write(dev_t dev, uio_t *uio, cred_t *cr)
1416 {
1417 minor_t minor = getminor(dev);
1418 zvol_state_t *zv;
1419 uint64_t volsize;
1420 rl_t *rl;
1421 int error = 0;
1422 boolean_t sync;
1423
1424 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL);
1425 if (zv == NULL)
1426 return (SET_ERROR(ENXIO));
1427
1428 volsize = zv->zv_volsize;
1429 if (uio->uio_resid > 0 &&
1430 (uio->uio_loffset < 0 || uio->uio_loffset >= volsize))
1431 return (SET_ERROR(EIO));
1432
1433 if (zv->zv_flags & ZVOL_DUMPIFIED) {
1434 error = physio(zvol_strategy, NULL, dev, B_WRITE,
1435 zvol_minphys, uio);
1436 return (error);
1437 }
1438
1439 sync = !(zv->zv_flags & ZVOL_WCE) ||
1440 (zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS);
1441
1442 rl = zfs_range_lock(&zv->zv_znode, uio->uio_loffset, uio->uio_resid,
1443 RL_WRITER);
1444 while (uio->uio_resid > 0 && uio->uio_loffset < volsize) {
1445 uint64_t bytes = MIN(uio->uio_resid, DMU_MAX_ACCESS >> 1);
1446 uint64_t off = uio->uio_loffset;
1447 dmu_tx_t *tx = dmu_tx_create(zv->zv_objset);
1448
1449 if (bytes > volsize - off) /* don't write past the end */
1450 bytes = volsize - off;
1451
1452 dmu_tx_hold_write(tx, ZVOL_OBJ, off, bytes);
1453 error = dmu_tx_assign(tx, TXG_WAIT);
1454 if (error) {
1455 dmu_tx_abort(tx);
1456 break;
1457 }
1458 error = dmu_write_uio_dbuf(zv->zv_dbuf, uio, bytes, tx);
1459 if (error == 0)
1460 zvol_log_write(zv, tx, off, bytes, sync);
1461 dmu_tx_commit(tx);
1462
1463 if (error)
1464 break;
1465 }
1466 zfs_range_unlock(rl);
1467 if (sync)
1468 zil_commit(zv->zv_zilog, ZVOL_OBJ);
1469 return (error);
1470 }
1471
1472 int
1473 zvol_getefi(void *arg, int flag, uint64_t vs, uint8_t bs)
1474 {
1475 struct uuid uuid = EFI_RESERVED;
1476 efi_gpe_t gpe = { 0 };
1477 uint32_t crc;
1478 dk_efi_t efi;
1479 int length;
1480 char *ptr;
1481
1482 if (ddi_copyin(arg, &efi, sizeof (dk_efi_t), flag))
1483 return (SET_ERROR(EFAULT));
1484 ptr = (char *)(uintptr_t)efi.dki_data_64;
1485 length = efi.dki_length;
1486 /*
1487 * Some clients may attempt to request a PMBR for the
1488 * zvol. Currently this interface will return EINVAL to
1489 * such requests. These requests could be supported by
1490 * adding a check for lba == 0 and consing up an appropriate
1491 * PMBR.
1492 */
1493 if (efi.dki_lba < 1 || efi.dki_lba > 2 || length <= 0)
1494 return (SET_ERROR(EINVAL));
1495
1496 gpe.efi_gpe_StartingLBA = LE_64(34ULL);
1497 gpe.efi_gpe_EndingLBA = LE_64((vs >> bs) - 1);
1498 UUID_LE_CONVERT(gpe.efi_gpe_PartitionTypeGUID, uuid);
1499
1500 if (efi.dki_lba == 1) {
1501 efi_gpt_t gpt = { 0 };
1502
1503 gpt.efi_gpt_Signature = LE_64(EFI_SIGNATURE);
1504 gpt.efi_gpt_Revision = LE_32(EFI_VERSION_CURRENT);
1505 gpt.efi_gpt_HeaderSize = LE_32(sizeof (gpt));
1506 gpt.efi_gpt_MyLBA = LE_64(1ULL);
1507 gpt.efi_gpt_FirstUsableLBA = LE_64(34ULL);
1508 gpt.efi_gpt_LastUsableLBA = LE_64((vs >> bs) - 1);
1509 gpt.efi_gpt_PartitionEntryLBA = LE_64(2ULL);
1510 gpt.efi_gpt_NumberOfPartitionEntries = LE_32(1);
1511 gpt.efi_gpt_SizeOfPartitionEntry =
1512 LE_32(sizeof (efi_gpe_t));
1513 CRC32(crc, &gpe, sizeof (gpe), -1U, crc32_table);
1514 gpt.efi_gpt_PartitionEntryArrayCRC32 = LE_32(~crc);
1515 CRC32(crc, &gpt, sizeof (gpt), -1U, crc32_table);
1516 gpt.efi_gpt_HeaderCRC32 = LE_32(~crc);
1517 if (ddi_copyout(&gpt, ptr, MIN(sizeof (gpt), length),
1518 flag))
1519 return (SET_ERROR(EFAULT));
1520 ptr += sizeof (gpt);
1521 length -= sizeof (gpt);
1522 }
1523 if (length > 0 && ddi_copyout(&gpe, ptr, MIN(sizeof (gpe),
1524 length), flag))
1525 return (SET_ERROR(EFAULT));
1526 return (0);
1527 }
1528
1529 /*
1530 * BEGIN entry points to allow external callers access to the volume.
1531 */
1532 /*
1533 * Return the volume parameters needed for access from an external caller.
1534 * These values are invariant as long as the volume is held open.
1535 */
1536 int
1537 zvol_get_volume_params(minor_t minor, uint64_t *blksize,
1538 uint64_t *max_xfer_len, void **minor_hdl, void **objset_hdl, void **zil_hdl,
1539 void **rl_hdl, void **bonus_hdl)
1540 {
1541 zvol_state_t *zv;
1542
1543 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL);
1544 if (zv == NULL)
1545 return (SET_ERROR(ENXIO));
1546 if (zv->zv_flags & ZVOL_DUMPIFIED)
1547 return (SET_ERROR(ENXIO));
1548
1549 ASSERT(blksize && max_xfer_len && minor_hdl &&
1550 objset_hdl && zil_hdl && rl_hdl && bonus_hdl);
1551
1552 *blksize = zv->zv_volblocksize;
1553 *max_xfer_len = (uint64_t)zvol_maxphys;
1554 *minor_hdl = zv;
1555 *objset_hdl = zv->zv_objset;
1556 *zil_hdl = zv->zv_zilog;
1557 *rl_hdl = &zv->zv_znode;
1558 *bonus_hdl = zv->zv_dbuf;
1559 return (0);
1560 }
1561
1562 /*
1563 * Return the current volume size to an external caller.
1564 * The size can change while the volume is open.
1565 */
1566 uint64_t
1567 zvol_get_volume_size(void *minor_hdl)
1568 {
1569 zvol_state_t *zv = minor_hdl;
1570
1571 return (zv->zv_volsize);
1572 }
1573
1574 /*
1575 * Return the current WCE setting to an external caller.
1576 * The WCE setting can change while the volume is open.
1577 */
1578 int
1579 zvol_get_volume_wce(void *minor_hdl)
1580 {
1581 zvol_state_t *zv = minor_hdl;
1582
1583 return ((zv->zv_flags & ZVOL_WCE) ? 1 : 0);
1584 }
1585
1586 /*
1587 * Entry point for external callers to zvol_log_write
1588 */
1589 void
1590 zvol_log_write_minor(void *minor_hdl, dmu_tx_t *tx, offset_t off, ssize_t resid,
1591 boolean_t sync)
1592 {
1593 zvol_state_t *zv = minor_hdl;
1594
1595 zvol_log_write(zv, tx, off, resid, sync);
1596 }
1597 /*
1598 * END entry points to allow external callers access to the volume.
1599 */
1600
1601 /*
1602 * Log a DKIOCFREE/free-long-range to the ZIL with TX_TRUNCATE.
1603 */
1604 static void
1605 zvol_log_truncate(zvol_state_t *zv, dmu_tx_t *tx, uint64_t off, uint64_t len,
1606 boolean_t sync)
1607 {
1608 itx_t *itx;
1609 lr_truncate_t *lr;
1610 zilog_t *zilog = zv->zv_zilog;
1611
1612 if (zil_replaying(zilog, tx))
1613 return;
1614
1615 itx = zil_itx_create(TX_TRUNCATE, sizeof (*lr));
1616 lr = (lr_truncate_t *)&itx->itx_lr;
1617 lr->lr_foid = ZVOL_OBJ;
1618 lr->lr_offset = off;
1619 lr->lr_length = len;
1620
1621 itx->itx_sync = sync;
1622 zil_itx_assign(zilog, itx, tx);
1623 }
1624
1625 /*
1626 * Dirtbag ioctls to support mkfs(1M) for UFS filesystems. See dkio(7I).
1627 * Also a dirtbag dkio ioctl for unmap/free-block functionality.
1628 */
1629 /*ARGSUSED*/
1630 int
1631 zvol_ioctl(dev_t dev, int cmd, intptr_t arg, int flag, cred_t *cr, int *rvalp)
1632 {
1633 zvol_state_t *zv;
1634 struct dk_callback *dkc;
1635 int error = 0;
1636 rl_t *rl;
1637
1638 mutex_enter(&zfsdev_state_lock);
1639
1640 zv = zfsdev_get_soft_state(getminor(dev), ZSST_ZVOL);
1641
1642 if (zv == NULL) {
1643 mutex_exit(&zfsdev_state_lock);
1644 return (SET_ERROR(ENXIO));
1645 }
1646 ASSERT(zv->zv_total_opens > 0);
1647
1648 switch (cmd) {
1649
1650 case DKIOCINFO:
1651 {
1652 struct dk_cinfo dki;
1653
1654 bzero(&dki, sizeof (dki));
1655 (void) strcpy(dki.dki_cname, "zvol");
1656 (void) strcpy(dki.dki_dname, "zvol");
1657 dki.dki_ctype = DKC_UNKNOWN;
1658 dki.dki_unit = getminor(dev);
1659 dki.dki_maxtransfer = 1 << (SPA_MAXBLOCKSHIFT - zv->zv_min_bs);
1660 mutex_exit(&zfsdev_state_lock);
1661 if (ddi_copyout(&dki, (void *)arg, sizeof (dki), flag))
1662 error = SET_ERROR(EFAULT);
1663 return (error);
1664 }
1665
1666 case DKIOCGMEDIAINFO:
1667 {
1668 struct dk_minfo dkm;
1669
1670 bzero(&dkm, sizeof (dkm));
1671 dkm.dki_lbsize = 1U << zv->zv_min_bs;
1672 dkm.dki_capacity = zv->zv_volsize >> zv->zv_min_bs;
1673 dkm.dki_media_type = DK_UNKNOWN;
1674 mutex_exit(&zfsdev_state_lock);
1675 if (ddi_copyout(&dkm, (void *)arg, sizeof (dkm), flag))
1676 error = SET_ERROR(EFAULT);
1677 return (error);
1678 }
1679
1680 case DKIOCGMEDIAINFOEXT:
1681 {
1682 struct dk_minfo_ext dkmext;
1683
1684 bzero(&dkmext, sizeof (dkmext));
1685 dkmext.dki_lbsize = 1U << zv->zv_min_bs;
1686 dkmext.dki_pbsize = zv->zv_volblocksize;
1687 dkmext.dki_capacity = zv->zv_volsize >> zv->zv_min_bs;
1688 dkmext.dki_media_type = DK_UNKNOWN;
1689 mutex_exit(&zfsdev_state_lock);
1690 if (ddi_copyout(&dkmext, (void *)arg, sizeof (dkmext), flag))
1691 error = SET_ERROR(EFAULT);
1692 return (error);
1693 }
1694
1695 case DKIOCGETEFI:
1696 {
1697 uint64_t vs = zv->zv_volsize;
1698 uint8_t bs = zv->zv_min_bs;
1699
1700 mutex_exit(&zfsdev_state_lock);
1701 error = zvol_getefi((void *)arg, flag, vs, bs);
1702 return (error);
1703 }
1704
1705 case DKIOCFLUSHWRITECACHE:
1706 dkc = (struct dk_callback *)arg;
1707 mutex_exit(&zfsdev_state_lock);
1708 zil_commit(zv->zv_zilog, ZVOL_OBJ);
1709 if ((flag & FKIOCTL) && dkc != NULL && dkc->dkc_callback) {
1710 (*dkc->dkc_callback)(dkc->dkc_cookie, error);
1711 error = 0;
1712 }
1713 return (error);
1714
1715 case DKIOCGETWCE:
1716 {
1717 int wce = (zv->zv_flags & ZVOL_WCE) ? 1 : 0;
1718 if (ddi_copyout(&wce, (void *)arg, sizeof (int),
1719 flag))
1720 error = SET_ERROR(EFAULT);
1721 break;
1722 }
1723 case DKIOCSETWCE:
1724 {
1725 int wce;
1726 if (ddi_copyin((void *)arg, &wce, sizeof (int),
1727 flag)) {
1728 error = SET_ERROR(EFAULT);
1729 break;
1730 }
1731 if (wce) {
1732 zv->zv_flags |= ZVOL_WCE;
1733 mutex_exit(&zfsdev_state_lock);
1734 } else {
1735 zv->zv_flags &= ~ZVOL_WCE;
1736 mutex_exit(&zfsdev_state_lock);
1737 zil_commit(zv->zv_zilog, ZVOL_OBJ);
1738 }
1739 return (0);
1740 }
1741
1742 case DKIOCGGEOM:
1743 case DKIOCGVTOC:
1744 /*
1745 * commands using these (like prtvtoc) expect ENOTSUP
1746 * since we're emulating an EFI label
1747 */
1748 error = SET_ERROR(ENOTSUP);
1749 break;
1750
1751 case DKIOCDUMPINIT:
1752 rl = zfs_range_lock(&zv->zv_znode, 0, zv->zv_volsize,
1753 RL_WRITER);
1754 error = zvol_dumpify(zv);
1755 zfs_range_unlock(rl);
1756 break;
1757
1758 case DKIOCDUMPFINI:
1759 if (!(zv->zv_flags & ZVOL_DUMPIFIED))
1760 break;
1761 rl = zfs_range_lock(&zv->zv_znode, 0, zv->zv_volsize,
1762 RL_WRITER);
1763 error = zvol_dump_fini(zv);
1764 zfs_range_unlock(rl);
1765 break;
1766
1767 case DKIOCFREE:
1768 {
1769 dkioc_free_t df;
1770 dmu_tx_t *tx;
1771
1772 if (ddi_copyin((void *)arg, &df, sizeof (df), flag)) {
1773 error = SET_ERROR(EFAULT);
1774 break;
1775 }
1776
1777 /*
1778 * Apply Postel's Law to length-checking. If they overshoot,
1779 * just blank out until the end, if there's a need to blank
1780 * out anything.
1781 */
1782 if (df.df_start >= zv->zv_volsize)
1783 break; /* No need to do anything... */
1784
1785 mutex_exit(&zfsdev_state_lock);
1786
1787 rl = zfs_range_lock(&zv->zv_znode, df.df_start, df.df_length,
1788 RL_WRITER);
1789 tx = dmu_tx_create(zv->zv_objset);
1790 dmu_tx_mark_netfree(tx);
1791 error = dmu_tx_assign(tx, TXG_WAIT);
1792 if (error != 0) {
1793 dmu_tx_abort(tx);
1794 } else {
1795 zvol_log_truncate(zv, tx, df.df_start,
1796 df.df_length, B_TRUE);
1797 dmu_tx_commit(tx);
1798 error = dmu_free_long_range(zv->zv_objset, ZVOL_OBJ,
1799 df.df_start, df.df_length);
1800 }
1801
1802 zfs_range_unlock(rl);
1803
1804 if (error == 0) {
1805 /*
1806 * If the write-cache is disabled or 'sync' property
1807 * is set to 'always' then treat this as a synchronous
1808 * operation (i.e. commit to zil).
1809 */
1810 if (!(zv->zv_flags & ZVOL_WCE) ||
1811 (zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS))
1812 zil_commit(zv->zv_zilog, ZVOL_OBJ);
1813
1814 /*
1815 * If the caller really wants synchronous writes, and
1816 * can't wait for them, don't return until the write
1817 * is done.
1818 */
1819 if (df.df_flags & DF_WAIT_SYNC) {
1820 txg_wait_synced(
1821 dmu_objset_pool(zv->zv_objset), 0);
1822 }
1823 }
1824 return (error);
1825 }
1826
1827 default:
1828 error = SET_ERROR(ENOTTY);
1829 break;
1830
1831 }
1832 mutex_exit(&zfsdev_state_lock);
1833 return (error);
1834 }
1835
1836 int
1837 zvol_busy(void)
1838 {
1839 return (zvol_minors != 0);
1840 }
1841
1842 void
1843 zvol_init(void)
1844 {
1845 VERIFY(ddi_soft_state_init(&zfsdev_state, sizeof (zfs_soft_state_t),
1846 1) == 0);
1847 mutex_init(&zfsdev_state_lock, NULL, MUTEX_DEFAULT, NULL);
1848 }
1849
1850 void
1851 zvol_fini(void)
1852 {
1853 mutex_destroy(&zfsdev_state_lock);
1854 ddi_soft_state_fini(&zfsdev_state);
1855 }
1856
1857 /*ARGSUSED*/
1858 static int
1859 zfs_mvdev_dump_feature_check(void *arg, dmu_tx_t *tx)
1860 {
1861 spa_t *spa = dmu_tx_pool(tx)->dp_spa;
1862
1863 if (spa_feature_is_active(spa, SPA_FEATURE_MULTI_VDEV_CRASH_DUMP))
1864 return (1);
1865 return (0);
1866 }
1867
1868 /*ARGSUSED*/
1869 static void
1870 zfs_mvdev_dump_activate_feature_sync(void *arg, dmu_tx_t *tx)
1871 {
1872 spa_t *spa = dmu_tx_pool(tx)->dp_spa;
1873
1874 spa_feature_incr(spa, SPA_FEATURE_MULTI_VDEV_CRASH_DUMP, tx);
1875 }
1876
1877 static int
1878 zvol_dump_init(zvol_state_t *zv, boolean_t resize)
1879 {
1880 dmu_tx_t *tx;
1881 int error;
1882 objset_t *os = zv->zv_objset;
1883 spa_t *spa = dmu_objset_spa(os);
1884 vdev_t *vd = spa->spa_root_vdev;
1885 nvlist_t *nv = NULL;
1886 uint64_t version = spa_version(spa);
1887 enum zio_checksum checksum;
1888
1889 ASSERT(MUTEX_HELD(&zfsdev_state_lock));
1890 ASSERT(vd->vdev_ops == &vdev_root_ops);
1891
1892 error = dmu_free_long_range(zv->zv_objset, ZVOL_OBJ, 0,
1893 DMU_OBJECT_END);
1894 /* wait for dmu_free_long_range to actually free the blocks */
1895 txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0);
1896
1897 /*
1898 * If the pool on which the dump device is being initialized has more
1899 * than one child vdev, check that the MULTI_VDEV_CRASH_DUMP feature is
1900 * enabled. If so, bump that feature's counter to indicate that the
1901 * feature is active. We also check the vdev type to handle the
1902 * following case:
1903 * # zpool create test raidz disk1 disk2 disk3
1904 * Now have spa_root_vdev->vdev_children == 1 (the raidz vdev),
1905 * the raidz vdev itself has 3 children.
1906 */
1907 if (vd->vdev_children > 1 || vd->vdev_ops == &vdev_raidz_ops) {
1908 if (!spa_feature_is_enabled(spa,
1909 SPA_FEATURE_MULTI_VDEV_CRASH_DUMP))
1910 return (SET_ERROR(ENOTSUP));
1911 (void) dsl_sync_task(spa_name(spa),
1912 zfs_mvdev_dump_feature_check,
1913 zfs_mvdev_dump_activate_feature_sync, NULL,
1914 2, ZFS_SPACE_CHECK_RESERVED);
1915 }
1916
1917 tx = dmu_tx_create(os);
1918 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL);
1919 dmu_tx_hold_bonus(tx, ZVOL_OBJ);
1920 error = dmu_tx_assign(tx, TXG_WAIT);
1921 if (error) {
1922 dmu_tx_abort(tx);
1923 return (error);
1924 }
1925
1926 /*
1927 * If MULTI_VDEV_CRASH_DUMP is active, use the NOPARITY checksum
1928 * function. Otherwise, use the old default -- OFF.
1929 */
1930 checksum = spa_feature_is_active(spa,
1931 SPA_FEATURE_MULTI_VDEV_CRASH_DUMP) ? ZIO_CHECKSUM_NOPARITY :
1932 ZIO_CHECKSUM_OFF;
1933
1934 /*
1935 * If we are resizing the dump device then we only need to
1936 * update the refreservation to match the newly updated
1937 * zvolsize. Otherwise, we save off the original state of the
1938 * zvol so that we can restore them if the zvol is ever undumpified.
1939 */
1940 if (resize) {
1941 error = zap_update(os, ZVOL_ZAP_OBJ,
1942 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1,
1943 &zv->zv_volsize, tx);
1944 } else {
1945 uint64_t checksum, compress, refresrv, vbs, dedup;
1946
1947 error = dsl_prop_get_integer(zv->zv_name,
1948 zfs_prop_to_name(ZFS_PROP_COMPRESSION), &compress, NULL);
1949 error = error ? error : dsl_prop_get_integer(zv->zv_name,
1950 zfs_prop_to_name(ZFS_PROP_CHECKSUM), &checksum, NULL);
1951 error = error ? error : dsl_prop_get_integer(zv->zv_name,
1952 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), &refresrv, NULL);
1953 error = error ? error : dsl_prop_get_integer(zv->zv_name,
1954 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), &vbs, NULL);
1955 if (version >= SPA_VERSION_DEDUP) {
1956 error = error ? error :
1957 dsl_prop_get_integer(zv->zv_name,
1958 zfs_prop_to_name(ZFS_PROP_DEDUP), &dedup, NULL);
1959 }
1960
1961 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ,
1962 zfs_prop_to_name(ZFS_PROP_COMPRESSION), 8, 1,
1963 &compress, tx);
1964 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ,
1965 zfs_prop_to_name(ZFS_PROP_CHECKSUM), 8, 1, &checksum, tx);
1966 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ,
1967 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1,
1968 &refresrv, tx);
1969 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ,
1970 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), 8, 1,
1971 &vbs, tx);
1972 error = error ? error : dmu_object_set_blocksize(
1973 os, ZVOL_OBJ, SPA_MAXBLOCKSIZE, 0, tx);
1974 if (version >= SPA_VERSION_DEDUP) {
1975 error = error ? error : zap_update(os, ZVOL_ZAP_OBJ,
1976 zfs_prop_to_name(ZFS_PROP_DEDUP), 8, 1,
1977 &dedup, tx);
1978 }
1979 if (error == 0)
1980 zv->zv_volblocksize = SPA_MAXBLOCKSIZE;
1981 }
1982 dmu_tx_commit(tx);
1983
1984 /*
1985 * We only need update the zvol's property if we are initializing
1986 * the dump area for the first time.
1987 */
1988 if (!resize) {
1989 VERIFY(nvlist_alloc(&nv, NV_UNIQUE_NAME, KM_SLEEP) == 0);
1990 VERIFY(nvlist_add_uint64(nv,
1991 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 0) == 0);
1992 VERIFY(nvlist_add_uint64(nv,
1993 zfs_prop_to_name(ZFS_PROP_COMPRESSION),
1994 ZIO_COMPRESS_OFF) == 0);
1995 VERIFY(nvlist_add_uint64(nv,
1996 zfs_prop_to_name(ZFS_PROP_CHECKSUM),
1997 checksum) == 0);
1998 if (version >= SPA_VERSION_DEDUP) {
1999 VERIFY(nvlist_add_uint64(nv,
2000 zfs_prop_to_name(ZFS_PROP_DEDUP),
2001 ZIO_CHECKSUM_OFF) == 0);
2002 }
2003
2004 error = zfs_set_prop_nvlist(zv->zv_name, ZPROP_SRC_LOCAL,
2005 nv, NULL);
2006 nvlist_free(nv);
2007
2008 if (error)
2009 return (error);
2010 }
2011
2012 /* Allocate the space for the dump */
2013 error = zvol_prealloc(zv);
2014 return (error);
2015 }
2016
2017 static int
2018 zvol_dumpify(zvol_state_t *zv)
2019 {
2020 int error = 0;
2021 uint64_t dumpsize = 0;
2022 dmu_tx_t *tx;
2023 objset_t *os = zv->zv_objset;
2024
2025 if (zv->zv_flags & ZVOL_RDONLY)
2026 return (SET_ERROR(EROFS));
2027
2028 if (zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE,
2029 8, 1, &dumpsize) != 0 || dumpsize != zv->zv_volsize) {
2030 boolean_t resize = (dumpsize > 0);
2031
2032 if ((error = zvol_dump_init(zv, resize)) != 0) {
2033 (void) zvol_dump_fini(zv);
2034 return (error);
2035 }
2036 }
2037
2038 /*
2039 * Build up our lba mapping.
2040 */
2041 error = zvol_get_lbas(zv);
2042 if (error) {
2043 (void) zvol_dump_fini(zv);
2044 return (error);
2045 }
2046
2047 tx = dmu_tx_create(os);
2048 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL);
2049 error = dmu_tx_assign(tx, TXG_WAIT);
2050 if (error) {
2051 dmu_tx_abort(tx);
2052 (void) zvol_dump_fini(zv);
2053 return (error);
2054 }
2055
2056 zv->zv_flags |= ZVOL_DUMPIFIED;
2057 error = zap_update(os, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE, 8, 1,
2058 &zv->zv_volsize, tx);
2059 dmu_tx_commit(tx);
2060
2061 if (error) {
2062 (void) zvol_dump_fini(zv);
2063 return (error);
2064 }
2065
2066 txg_wait_synced(dmu_objset_pool(os), 0);
2067 return (0);
2068 }
2069
2070 static int
2071 zvol_dump_fini(zvol_state_t *zv)
2072 {
2073 dmu_tx_t *tx;
2074 objset_t *os = zv->zv_objset;
2075 nvlist_t *nv;
2076 int error = 0;
2077 uint64_t checksum, compress, refresrv, vbs, dedup;
2078 uint64_t version = spa_version(dmu_objset_spa(zv->zv_objset));
2079
2080 /*
2081 * Attempt to restore the zvol back to its pre-dumpified state.
2082 * This is a best-effort attempt as it's possible that not all
2083 * of these properties were initialized during the dumpify process
2084 * (i.e. error during zvol_dump_init).
2085 */
2086
2087 tx = dmu_tx_create(os);
2088 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL);
2089 error = dmu_tx_assign(tx, TXG_WAIT);
2090 if (error) {
2091 dmu_tx_abort(tx);
2092 return (error);
2093 }
2094 (void) zap_remove(os, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE, tx);
2095 dmu_tx_commit(tx);
2096
2097 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ,
2098 zfs_prop_to_name(ZFS_PROP_CHECKSUM), 8, 1, &checksum);
2099 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ,
2100 zfs_prop_to_name(ZFS_PROP_COMPRESSION), 8, 1, &compress);
2101 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ,
2102 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1, &refresrv);
2103 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ,
2104 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), 8, 1, &vbs);
2105
2106 VERIFY(nvlist_alloc(&nv, NV_UNIQUE_NAME, KM_SLEEP) == 0);
2107 (void) nvlist_add_uint64(nv,
2108 zfs_prop_to_name(ZFS_PROP_CHECKSUM), checksum);
2109 (void) nvlist_add_uint64(nv,
2110 zfs_prop_to_name(ZFS_PROP_COMPRESSION), compress);
2111 (void) nvlist_add_uint64(nv,
2112 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), refresrv);
2113 if (version >= SPA_VERSION_DEDUP &&
2114 zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ,
2115 zfs_prop_to_name(ZFS_PROP_DEDUP), 8, 1, &dedup) == 0) {
2116 (void) nvlist_add_uint64(nv,
2117 zfs_prop_to_name(ZFS_PROP_DEDUP), dedup);
2118 }
2119 (void) zfs_set_prop_nvlist(zv->zv_name, ZPROP_SRC_LOCAL,
2120 nv, NULL);
2121 nvlist_free(nv);
2122
2123 zvol_free_extents(zv);
2124 zv->zv_flags &= ~ZVOL_DUMPIFIED;
2125 (void) dmu_free_long_range(os, ZVOL_OBJ, 0, DMU_OBJECT_END);
2126 /* wait for dmu_free_long_range to actually free the blocks */
2127 txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0);
2128 tx = dmu_tx_create(os);
2129 dmu_tx_hold_bonus(tx, ZVOL_OBJ);
2130 error = dmu_tx_assign(tx, TXG_WAIT);
2131 if (error) {
2132 dmu_tx_abort(tx);
2133 return (error);
2134 }
2135 if (dmu_object_set_blocksize(os, ZVOL_OBJ, vbs, 0, tx) == 0)
2136 zv->zv_volblocksize = vbs;
2137 dmu_tx_commit(tx);
2138
2139 return (0);
2140 }
Unleashed OS