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 * Copyright (c) 2006-2010 Pawel Jakub Dawidek <pjd@FreeBSD.org>
25 * All rights reserved.
26 *
27 * Portions Copyright 2010 Robert Milkowski
28 *
29 * Copyright 2011 Nexenta Systems, Inc. All rights reserved.
30 * Copyright (c) 2012, 2014 by Delphix. All rights reserved.
31 * Copyright (c) 2013, Joyent, Inc. All rights reserved.
32 */
33
34 /* Portions Copyright 2011 Martin Matuska <mm@FreeBSD.org> */
35
36 /*
37 * ZFS volume emulation driver.
38 *
39 * Makes a DMU object look like a volume of arbitrary size, up to 2^64 bytes.
40 * Volumes are accessed through the symbolic links named:
41 *
42 * /dev/zvol/dsk/<pool_name>/<dataset_name>
43 * /dev/zvol/rdsk/<pool_name>/<dataset_name>
44 *
45 * These links are created by the /dev filesystem (sdev_zvolops.c).
46 * Volumes are persistent through reboot. No user command needs to be
47 * run before opening and using a device.
48 *
49 * FreeBSD notes.
50 * On FreeBSD ZVOLs are simply GEOM providers like any other storage device
51 * in the system.
52 */
53
54 #include <sys/types.h>
55 #include <sys/param.h>
56 #include <sys/kernel.h>
57 #include <sys/errno.h>
58 #include <sys/uio.h>
59 #include <sys/bio.h>
60 #include <sys/buf.h>
61 #include <sys/kmem.h>
62 #include <sys/conf.h>
63 #include <sys/cmn_err.h>
64 #include <sys/stat.h>
65 #include <sys/zap.h>
66 #include <sys/spa.h>
67 #include <sys/spa_impl.h>
68 #include <sys/zio.h>
69 #include <sys/disk.h>
70 #include <sys/dmu_traverse.h>
71 #include <sys/dnode.h>
72 #include <sys/dsl_dataset.h>
73 #include <sys/dsl_prop.h>
74 #include <sys/dkio.h>
75 #include <sys/byteorder.h>
76 #include <sys/sunddi.h>
77 #include <sys/dirent.h>
78 #include <sys/policy.h>
79 #include <sys/queue.h>
80 #include <sys/fs/zfs.h>
81 #include <sys/zfs_ioctl.h>
82 #include <sys/zil.h>
83 #include <sys/refcount.h>
84 #include <sys/zfs_znode.h>
85 #include <sys/zfs_rlock.h>
86 #include <sys/vdev_impl.h>
87 #include <sys/vdev_raidz.h>
88 #include <sys/zvol.h>
89 #include <sys/zil_impl.h>
90 #include <sys/dbuf.h>
91 #include <sys/dmu_tx.h>
92 #include <sys/zfeature.h>
93 #include <sys/zio_checksum.h>
94 #include <sys/filio.h>
95
96 #include <geom/geom.h>
97
98 #include "zfs_namecheck.h"
99
100 #ifndef illumos
101 struct g_class zfs_zvol_class = {
102 .name = "ZFS::ZVOL",
103 .version = G_VERSION,
104 };
105
106 DECLARE_GEOM_CLASS(zfs_zvol_class, zfs_zvol);
107
108 #endif
109 void *zfsdev_state;
110 static char *zvol_tag = "zvol_tag";
111
112 #define ZVOL_DUMPSIZE "dumpsize"
113
114 /*
115 * This lock protects the zfsdev_state structure from being modified
116 * while it's being used, e.g. an open that comes in before a create
117 * finishes. It also protects temporary opens of the dataset so that,
118 * e.g., an open doesn't get a spurious EBUSY.
119 */
120 #ifdef illumos
121 kmutex_t zfsdev_state_lock;
122 #else
123 /*
124 * In FreeBSD we've replaced the upstream zfsdev_state_lock with the
125 * spa_namespace_lock in the ZVOL code.
126 */
127 #define zfsdev_state_lock spa_namespace_lock
128 #endif
129 static uint32_t zvol_minors;
130
131 #ifndef illumos
132 SYSCTL_DECL(_vfs_zfs);
133 SYSCTL_NODE(_vfs_zfs, OID_AUTO, vol, CTLFLAG_RW, 0, "ZFS VOLUME");
134 static int volmode = ZFS_VOLMODE_GEOM;
135 SYSCTL_INT(_vfs_zfs_vol, OID_AUTO, mode, CTLFLAG_RWTUN, &volmode, 0,
136 "Expose as GEOM providers (1), device files (2) or neither");
137
138 #endif
139 typedef struct zvol_extent {
140 list_node_t ze_node;
141 dva_t ze_dva; /* dva associated with this extent */
142 uint64_t ze_nblks; /* number of blocks in extent */
143 } zvol_extent_t;
144
145 /*
146 * The in-core state of each volume.
147 */
148 typedef struct zvol_state {
149 #ifndef illumos
150 LIST_ENTRY(zvol_state) zv_links;
151 #endif
152 char zv_name[MAXPATHLEN]; /* pool/dd name */
153 uint64_t zv_volsize; /* amount of space we advertise */
154 uint64_t zv_volblocksize; /* volume block size */
155 #ifdef illumos
156 minor_t zv_minor; /* minor number */
157 #else
158 struct cdev *zv_dev; /* non-GEOM device */
159 struct g_provider *zv_provider; /* GEOM provider */
160 #endif
161 uint8_t zv_min_bs; /* minimum addressable block shift */
162 uint8_t zv_flags; /* readonly, dumpified, etc. */
163 objset_t *zv_objset; /* objset handle */
164 #ifdef illumos
165 uint32_t zv_open_count[OTYPCNT]; /* open counts */
166 #endif
167 uint32_t zv_total_opens; /* total open count */
168 zilog_t *zv_zilog; /* ZIL handle */
169 list_t zv_extents; /* List of extents for dump */
170 znode_t zv_znode; /* for range locking */
171 dmu_buf_t *zv_dbuf; /* bonus handle */
172 #ifndef illumos
173 int zv_state;
174 int zv_volmode; /* Provide GEOM or cdev */
175 struct bio_queue_head zv_queue;
176 struct mtx zv_queue_mtx; /* zv_queue mutex */
177 #endif
178 } zvol_state_t;
179
180 #ifndef illumos
181 static LIST_HEAD(, zvol_state) all_zvols;
182 #endif
183 /*
184 * zvol specific flags
185 */
186 #define ZVOL_RDONLY 0x1
187 #define ZVOL_DUMPIFIED 0x2
188 #define ZVOL_EXCL 0x4
189 #define ZVOL_WCE 0x8
190
191 /*
192 * zvol maximum transfer in one DMU tx.
193 */
194 int zvol_maxphys = DMU_MAX_ACCESS/2;
195
196 /*
197 * Toggle unmap functionality.
198 */
199 boolean_t zvol_unmap_enabled = B_TRUE;
200 #ifndef illumos
201 SYSCTL_INT(_vfs_zfs_vol, OID_AUTO, unmap_enabled, CTLFLAG_RWTUN,
202 &zvol_unmap_enabled, 0,
203 "Enable UNMAP functionality");
204
205 static d_open_t zvol_d_open;
206 static d_close_t zvol_d_close;
207 static d_read_t zvol_read;
208 static d_write_t zvol_write;
209 static d_ioctl_t zvol_d_ioctl;
210 static d_strategy_t zvol_strategy;
211
212 static struct cdevsw zvol_cdevsw = {
213 .d_version = D_VERSION,
214 .d_open = zvol_d_open,
215 .d_close = zvol_d_close,
216 .d_read = zvol_read,
217 .d_write = zvol_write,
218 .d_ioctl = zvol_d_ioctl,
219 .d_strategy = zvol_strategy,
220 .d_name = "zvol",
221 .d_flags = D_DISK | D_TRACKCLOSE,
222 };
223
224 static void zvol_geom_run(zvol_state_t *zv);
225 static void zvol_geom_destroy(zvol_state_t *zv);
226 static int zvol_geom_access(struct g_provider *pp, int acr, int acw, int ace);
227 static void zvol_geom_start(struct bio *bp);
228 static void zvol_geom_worker(void *arg);
229 static void zvol_log_truncate(zvol_state_t *zv, dmu_tx_t *tx, uint64_t off,
230 uint64_t len, boolean_t sync);
231 #endif /* !illumos */
232
233 extern int zfs_set_prop_nvlist(const char *, zprop_source_t,
234 nvlist_t *, nvlist_t *);
235 static int zvol_remove_zv(zvol_state_t *);
236 static int zvol_get_data(void *arg, lr_write_t *lr, char *buf, zio_t *zio);
237 static int zvol_dumpify(zvol_state_t *zv);
238 static int zvol_dump_fini(zvol_state_t *zv);
239 static int zvol_dump_init(zvol_state_t *zv, boolean_t resize);
240
241 static void
zvol_size_changed(zvol_state_t * zv,uint64_t volsize)242 zvol_size_changed(zvol_state_t *zv, uint64_t volsize)
243 {
244 #ifdef illumos
245 dev_t dev = makedevice(ddi_driver_major(zfs_dip), zv->zv_minor);
246
247 zv->zv_volsize = volsize;
248 VERIFY(ddi_prop_update_int64(dev, zfs_dip,
249 "Size", volsize) == DDI_SUCCESS);
250 VERIFY(ddi_prop_update_int64(dev, zfs_dip,
251 "Nblocks", lbtodb(volsize)) == DDI_SUCCESS);
252
253 /* Notify specfs to invalidate the cached size */
254 spec_size_invalidate(dev, VBLK);
255 spec_size_invalidate(dev, VCHR);
256 #else /* !illumos */
257 zv->zv_volsize = volsize;
258 if (zv->zv_volmode == ZFS_VOLMODE_GEOM) {
259 struct g_provider *pp;
260
261 pp = zv->zv_provider;
262 if (pp == NULL)
263 return;
264 g_topology_lock();
265 g_resize_provider(pp, zv->zv_volsize);
266 g_topology_unlock();
267 }
268 #endif /* illumos */
269 }
270
271 int
zvol_check_volsize(uint64_t volsize,uint64_t blocksize)272 zvol_check_volsize(uint64_t volsize, uint64_t blocksize)
273 {
274 if (volsize == 0)
275 return (SET_ERROR(EINVAL));
276
277 if (volsize % blocksize != 0)
278 return (SET_ERROR(EINVAL));
279
280 #ifdef _ILP32
281 if (volsize - 1 > SPEC_MAXOFFSET_T)
282 return (SET_ERROR(EOVERFLOW));
283 #endif
284 return (0);
285 }
286
287 int
zvol_check_volblocksize(uint64_t volblocksize)288 zvol_check_volblocksize(uint64_t volblocksize)
289 {
290 if (volblocksize < SPA_MINBLOCKSIZE ||
291 volblocksize > SPA_OLD_MAXBLOCKSIZE ||
292 !ISP2(volblocksize))
293 return (SET_ERROR(EDOM));
294
295 return (0);
296 }
297
298 int
zvol_get_stats(objset_t * os,nvlist_t * nv)299 zvol_get_stats(objset_t *os, nvlist_t *nv)
300 {
301 int error;
302 dmu_object_info_t doi;
303 uint64_t val;
304
305 error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &val);
306 if (error)
307 return (error);
308
309 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_VOLSIZE, val);
310
311 error = dmu_object_info(os, ZVOL_OBJ, &doi);
312
313 if (error == 0) {
314 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_VOLBLOCKSIZE,
315 doi.doi_data_block_size);
316 }
317
318 return (error);
319 }
320
321 static zvol_state_t *
zvol_minor_lookup(const char * name)322 zvol_minor_lookup(const char *name)
323 {
324 #ifdef illumos
325 minor_t minor;
326 #endif
327 zvol_state_t *zv;
328
329 ASSERT(MUTEX_HELD(&zfsdev_state_lock));
330
331 #ifdef illumos
332 for (minor = 1; minor <= ZFSDEV_MAX_MINOR; minor++) {
333 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL);
334 if (zv == NULL)
335 continue;
336 #else
337 LIST_FOREACH(zv, &all_zvols, zv_links) {
338 #endif
339 if (strcmp(zv->zv_name, name) == 0)
340 return (zv);
341 }
342
343 return (NULL);
344 }
345
346 /* extent mapping arg */
347 struct maparg {
348 zvol_state_t *ma_zv;
349 uint64_t ma_blks;
350 };
351
352 /*ARGSUSED*/
353 static int
354 zvol_map_block(spa_t *spa, zilog_t *zilog, const blkptr_t *bp,
355 const zbookmark_phys_t *zb, const dnode_phys_t *dnp, void *arg)
356 {
357 struct maparg *ma = arg;
358 zvol_extent_t *ze;
359 int bs = ma->ma_zv->zv_volblocksize;
360
361 if (bp == NULL || BP_IS_HOLE(bp) ||
362 zb->zb_object != ZVOL_OBJ || zb->zb_level != 0)
363 return (0);
364
365 VERIFY(!BP_IS_EMBEDDED(bp));
366
367 VERIFY3U(ma->ma_blks, ==, zb->zb_blkid);
368 ma->ma_blks++;
369
370 /* Abort immediately if we have encountered gang blocks */
371 if (BP_IS_GANG(bp))
372 return (SET_ERROR(EFRAGS));
373
374 /*
375 * See if the block is at the end of the previous extent.
376 */
377 ze = list_tail(&ma->ma_zv->zv_extents);
378 if (ze &&
379 DVA_GET_VDEV(BP_IDENTITY(bp)) == DVA_GET_VDEV(&ze->ze_dva) &&
380 DVA_GET_OFFSET(BP_IDENTITY(bp)) ==
381 DVA_GET_OFFSET(&ze->ze_dva) + ze->ze_nblks * bs) {
382 ze->ze_nblks++;
383 return (0);
384 }
385
386 dprintf_bp(bp, "%s", "next blkptr:");
387
388 /* start a new extent */
389 ze = kmem_zalloc(sizeof (zvol_extent_t), KM_SLEEP);
390 ze->ze_dva = bp->blk_dva[0]; /* structure assignment */
391 ze->ze_nblks = 1;
392 list_insert_tail(&ma->ma_zv->zv_extents, ze);
393 return (0);
394 }
395
396 static void
397 zvol_free_extents(zvol_state_t *zv)
398 {
399 zvol_extent_t *ze;
400
401 while (ze = list_head(&zv->zv_extents)) {
402 list_remove(&zv->zv_extents, ze);
403 kmem_free(ze, sizeof (zvol_extent_t));
404 }
405 }
406
407 static int
408 zvol_get_lbas(zvol_state_t *zv)
409 {
410 objset_t *os = zv->zv_objset;
411 struct maparg ma;
412 int err;
413
414 ma.ma_zv = zv;
415 ma.ma_blks = 0;
416 zvol_free_extents(zv);
417
418 /* commit any in-flight changes before traversing the dataset */
419 txg_wait_synced(dmu_objset_pool(os), 0);
420 err = traverse_dataset(dmu_objset_ds(os), 0,
421 TRAVERSE_PRE | TRAVERSE_PREFETCH_METADATA, zvol_map_block, &ma);
422 if (err || ma.ma_blks != (zv->zv_volsize / zv->zv_volblocksize)) {
423 zvol_free_extents(zv);
424 return (err ? err : EIO);
425 }
426
427 return (0);
428 }
429
430 /* ARGSUSED */
431 void
432 zvol_create_cb(objset_t *os, void *arg, cred_t *cr, dmu_tx_t *tx)
433 {
434 zfs_creat_t *zct = arg;
435 nvlist_t *nvprops = zct->zct_props;
436 int error;
437 uint64_t volblocksize, volsize;
438
439 VERIFY(nvlist_lookup_uint64(nvprops,
440 zfs_prop_to_name(ZFS_PROP_VOLSIZE), &volsize) == 0);
441 if (nvlist_lookup_uint64(nvprops,
442 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), &volblocksize) != 0)
443 volblocksize = zfs_prop_default_numeric(ZFS_PROP_VOLBLOCKSIZE);
444
445 /*
446 * These properties must be removed from the list so the generic
447 * property setting step won't apply to them.
448 */
449 VERIFY(nvlist_remove_all(nvprops,
450 zfs_prop_to_name(ZFS_PROP_VOLSIZE)) == 0);
451 (void) nvlist_remove_all(nvprops,
452 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE));
453
454 error = dmu_object_claim(os, ZVOL_OBJ, DMU_OT_ZVOL, volblocksize,
455 DMU_OT_NONE, 0, tx);
456 ASSERT(error == 0);
457
458 error = zap_create_claim(os, ZVOL_ZAP_OBJ, DMU_OT_ZVOL_PROP,
459 DMU_OT_NONE, 0, tx);
460 ASSERT(error == 0);
461
462 error = zap_update(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize, tx);
463 ASSERT(error == 0);
464 }
465
466 /*
467 * Replay a TX_TRUNCATE ZIL transaction if asked. TX_TRUNCATE is how we
468 * implement DKIOCFREE/free-long-range.
469 */
470 static int
471 zvol_replay_truncate(zvol_state_t *zv, lr_truncate_t *lr, boolean_t byteswap)
472 {
473 uint64_t offset, length;
474
475 if (byteswap)
476 byteswap_uint64_array(lr, sizeof (*lr));
477
478 offset = lr->lr_offset;
479 length = lr->lr_length;
480
481 return (dmu_free_long_range(zv->zv_objset, ZVOL_OBJ, offset, length));
482 }
483
484 /*
485 * Replay a TX_WRITE ZIL transaction that didn't get committed
486 * after a system failure
487 */
488 static int
489 zvol_replay_write(zvol_state_t *zv, lr_write_t *lr, boolean_t byteswap)
490 {
491 objset_t *os = zv->zv_objset;
492 char *data = (char *)(lr + 1); /* data follows lr_write_t */
493 uint64_t offset, length;
494 dmu_tx_t *tx;
495 int error;
496
497 if (byteswap)
498 byteswap_uint64_array(lr, sizeof (*lr));
499
500 offset = lr->lr_offset;
501 length = lr->lr_length;
502
503 /* If it's a dmu_sync() block, write the whole block */
504 if (lr->lr_common.lrc_reclen == sizeof (lr_write_t)) {
505 uint64_t blocksize = BP_GET_LSIZE(&lr->lr_blkptr);
506 if (length < blocksize) {
507 offset -= offset % blocksize;
508 length = blocksize;
509 }
510 }
511
512 tx = dmu_tx_create(os);
513 dmu_tx_hold_write(tx, ZVOL_OBJ, offset, length);
514 error = dmu_tx_assign(tx, TXG_WAIT);
515 if (error) {
516 dmu_tx_abort(tx);
517 } else {
518 dmu_write(os, ZVOL_OBJ, offset, length, data, tx);
519 dmu_tx_commit(tx);
520 }
521
522 return (error);
523 }
524
525 /* ARGSUSED */
526 static int
527 zvol_replay_err(zvol_state_t *zv, lr_t *lr, boolean_t byteswap)
528 {
529 return (SET_ERROR(ENOTSUP));
530 }
531
532 /*
533 * Callback vectors for replaying records.
534 * Only TX_WRITE and TX_TRUNCATE are needed for zvol.
535 */
536 zil_replay_func_t *zvol_replay_vector[TX_MAX_TYPE] = {
537 zvol_replay_err, /* 0 no such transaction type */
538 zvol_replay_err, /* TX_CREATE */
539 zvol_replay_err, /* TX_MKDIR */
540 zvol_replay_err, /* TX_MKXATTR */
541 zvol_replay_err, /* TX_SYMLINK */
542 zvol_replay_err, /* TX_REMOVE */
543 zvol_replay_err, /* TX_RMDIR */
544 zvol_replay_err, /* TX_LINK */
545 zvol_replay_err, /* TX_RENAME */
546 zvol_replay_write, /* TX_WRITE */
547 zvol_replay_truncate, /* TX_TRUNCATE */
548 zvol_replay_err, /* TX_SETATTR */
549 zvol_replay_err, /* TX_ACL */
550 zvol_replay_err, /* TX_CREATE_ACL */
551 zvol_replay_err, /* TX_CREATE_ATTR */
552 zvol_replay_err, /* TX_CREATE_ACL_ATTR */
553 zvol_replay_err, /* TX_MKDIR_ACL */
554 zvol_replay_err, /* TX_MKDIR_ATTR */
555 zvol_replay_err, /* TX_MKDIR_ACL_ATTR */
556 zvol_replay_err, /* TX_WRITE2 */
557 };
558
559 #ifdef illumos
560 int
561 zvol_name2minor(const char *name, minor_t *minor)
562 {
563 zvol_state_t *zv;
564
565 mutex_enter(&zfsdev_state_lock);
566 zv = zvol_minor_lookup(name);
567 if (minor && zv)
568 *minor = zv->zv_minor;
569 mutex_exit(&zfsdev_state_lock);
570 return (zv ? 0 : -1);
571 }
572 #endif /* illumos */
573
574 /*
575 * Create a minor node (plus a whole lot more) for the specified volume.
576 */
577 int
578 zvol_create_minor(const char *name)
579 {
580 zfs_soft_state_t *zs;
581 zvol_state_t *zv;
582 objset_t *os;
583 dmu_object_info_t doi;
584 #ifdef illumos
585 minor_t minor = 0;
586 char chrbuf[30], blkbuf[30];
587 #else
588 struct cdev *dev;
589 struct g_provider *pp;
590 struct g_geom *gp;
591 uint64_t volsize, mode;
592 #endif
593 int error;
594
595 #ifndef illumos
596 ZFS_LOG(1, "Creating ZVOL %s...", name);
597 #endif
598
599 mutex_enter(&zfsdev_state_lock);
600
601 if (zvol_minor_lookup(name) != NULL) {
602 mutex_exit(&zfsdev_state_lock);
603 return (SET_ERROR(EEXIST));
604 }
605
606 /* lie and say we're read-only */
607 error = dmu_objset_own(name, DMU_OST_ZVOL, B_TRUE, FTAG, &os);
608
609 if (error) {
610 mutex_exit(&zfsdev_state_lock);
611 return (error);
612 }
613
614 #ifdef illumos
615 if ((minor = zfsdev_minor_alloc()) == 0) {
616 dmu_objset_disown(os, FTAG);
617 mutex_exit(&zfsdev_state_lock);
618 return (SET_ERROR(ENXIO));
619 }
620
621 if (ddi_soft_state_zalloc(zfsdev_state, minor) != DDI_SUCCESS) {
622 dmu_objset_disown(os, FTAG);
623 mutex_exit(&zfsdev_state_lock);
624 return (SET_ERROR(EAGAIN));
625 }
626 (void) ddi_prop_update_string(minor, zfs_dip, ZVOL_PROP_NAME,
627 (char *)name);
628
629 (void) snprintf(chrbuf, sizeof (chrbuf), "%u,raw", minor);
630
631 if (ddi_create_minor_node(zfs_dip, chrbuf, S_IFCHR,
632 minor, DDI_PSEUDO, 0) == DDI_FAILURE) {
633 ddi_soft_state_free(zfsdev_state, minor);
634 dmu_objset_disown(os, FTAG);
635 mutex_exit(&zfsdev_state_lock);
636 return (SET_ERROR(EAGAIN));
637 }
638
639 (void) snprintf(blkbuf, sizeof (blkbuf), "%u", minor);
640
641 if (ddi_create_minor_node(zfs_dip, blkbuf, S_IFBLK,
642 minor, DDI_PSEUDO, 0) == DDI_FAILURE) {
643 ddi_remove_minor_node(zfs_dip, chrbuf);
644 ddi_soft_state_free(zfsdev_state, minor);
645 dmu_objset_disown(os, FTAG);
646 mutex_exit(&zfsdev_state_lock);
647 return (SET_ERROR(EAGAIN));
648 }
649
650 zs = ddi_get_soft_state(zfsdev_state, minor);
651 zs->zss_type = ZSST_ZVOL;
652 zv = zs->zss_data = kmem_zalloc(sizeof (zvol_state_t), KM_SLEEP);
653 #else /* !illumos */
654
655 zv = kmem_zalloc(sizeof(*zv), KM_SLEEP);
656 zv->zv_state = 0;
657 error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize);
658 if (error) {
659 kmem_free(zv, sizeof(*zv));
660 dmu_objset_disown(os, zvol_tag);
661 mutex_exit(&zfsdev_state_lock);
662 return (error);
663 }
664 error = dsl_prop_get_integer(name,
665 zfs_prop_to_name(ZFS_PROP_VOLMODE), &mode, NULL);
666 if (error != 0 || mode == ZFS_VOLMODE_DEFAULT)
667 mode = volmode;
668
669 DROP_GIANT();
670 zv->zv_volsize = volsize;
671 zv->zv_volmode = mode;
672 if (zv->zv_volmode == ZFS_VOLMODE_GEOM) {
673 g_topology_lock();
674 gp = g_new_geomf(&zfs_zvol_class, "zfs::zvol::%s", name);
675 gp->start = zvol_geom_start;
676 gp->access = zvol_geom_access;
677 pp = g_new_providerf(gp, "%s/%s", ZVOL_DRIVER, name);
678 pp->flags |= G_PF_DIRECT_RECEIVE | G_PF_DIRECT_SEND;
679 pp->sectorsize = DEV_BSIZE;
680 pp->mediasize = zv->zv_volsize;
681 pp->private = zv;
682
683 zv->zv_provider = pp;
684 bioq_init(&zv->zv_queue);
685 mtx_init(&zv->zv_queue_mtx, "zvol", NULL, MTX_DEF);
686 } else if (zv->zv_volmode == ZFS_VOLMODE_DEV) {
687 if (make_dev_p(MAKEDEV_CHECKNAME | MAKEDEV_WAITOK,
688 &dev, &zvol_cdevsw, NULL, UID_ROOT, GID_OPERATOR,
689 0640, "%s/%s", ZVOL_DRIVER, name) != 0) {
690 kmem_free(zv, sizeof(*zv));
691 dmu_objset_disown(os, FTAG);
692 mutex_exit(&zfsdev_state_lock);
693 return (SET_ERROR(ENXIO));
694 }
695 zv->zv_dev = dev;
696 dev->si_iosize_max = MAXPHYS;
697 dev->si_drv2 = zv;
698 }
699 LIST_INSERT_HEAD(&all_zvols, zv, zv_links);
700 #endif /* illumos */
701
702 (void) strlcpy(zv->zv_name, name, MAXPATHLEN);
703 zv->zv_min_bs = DEV_BSHIFT;
704 #ifdef illumos
705 zv->zv_minor = minor;
706 #endif
707 zv->zv_objset = os;
708 if (dmu_objset_is_snapshot(os) || !spa_writeable(dmu_objset_spa(os)))
709 zv->zv_flags |= ZVOL_RDONLY;
710 mutex_init(&zv->zv_znode.z_range_lock, NULL, MUTEX_DEFAULT, NULL);
711 avl_create(&zv->zv_znode.z_range_avl, zfs_range_compare,
712 sizeof (rl_t), offsetof(rl_t, r_node));
713 list_create(&zv->zv_extents, sizeof (zvol_extent_t),
714 offsetof(zvol_extent_t, ze_node));
715 /* get and cache the blocksize */
716 error = dmu_object_info(os, ZVOL_OBJ, &doi);
717 ASSERT(error == 0);
718 zv->zv_volblocksize = doi.doi_data_block_size;
719
720 if (spa_writeable(dmu_objset_spa(os))) {
721 if (zil_replay_disable)
722 zil_destroy(dmu_objset_zil(os), B_FALSE);
723 else
724 zil_replay(os, zv, zvol_replay_vector);
725 }
726 dmu_objset_disown(os, FTAG);
727 zv->zv_objset = NULL;
728
729 zvol_minors++;
730
731 mutex_exit(&zfsdev_state_lock);
732 #ifndef illumos
733 if (zv->zv_volmode == ZFS_VOLMODE_GEOM) {
734 zvol_geom_run(zv);
735 g_topology_unlock();
736 }
737 PICKUP_GIANT();
738
739 ZFS_LOG(1, "ZVOL %s created.", name);
740 #endif
741
742 return (0);
743 }
744
745 /*
746 * Remove minor node for the specified volume.
747 */
748 static int
749 zvol_remove_zv(zvol_state_t *zv)
750 {
751 #ifdef illumos
752 char nmbuf[20];
753 minor_t minor = zv->zv_minor;
754 #endif
755
756 ASSERT(MUTEX_HELD(&zfsdev_state_lock));
757 if (zv->zv_total_opens != 0)
758 return (SET_ERROR(EBUSY));
759
760 #ifdef illumos
761 (void) snprintf(nmbuf, sizeof (nmbuf), "%u,raw", minor);
762 ddi_remove_minor_node(zfs_dip, nmbuf);
763
764 (void) snprintf(nmbuf, sizeof (nmbuf), "%u", minor);
765 ddi_remove_minor_node(zfs_dip, nmbuf);
766 #else
767 ZFS_LOG(1, "ZVOL %s destroyed.", zv->zv_name);
768
769 LIST_REMOVE(zv, zv_links);
770 if (zv->zv_volmode == ZFS_VOLMODE_GEOM) {
771 g_topology_lock();
772 zvol_geom_destroy(zv);
773 g_topology_unlock();
774 } else if (zv->zv_volmode == ZFS_VOLMODE_DEV)
775 destroy_dev(zv->zv_dev);
776 #endif
777
778 avl_destroy(&zv->zv_znode.z_range_avl);
779 mutex_destroy(&zv->zv_znode.z_range_lock);
780
781 kmem_free(zv, sizeof (zvol_state_t));
782 #ifdef illumos
783 ddi_soft_state_free(zfsdev_state, minor);
784 #endif
785 zvol_minors--;
786 return (0);
787 }
788
789 int
790 zvol_remove_minor(const char *name)
791 {
792 zvol_state_t *zv;
793 int rc;
794
795 mutex_enter(&zfsdev_state_lock);
796 if ((zv = zvol_minor_lookup(name)) == NULL) {
797 mutex_exit(&zfsdev_state_lock);
798 return (SET_ERROR(ENXIO));
799 }
800 rc = zvol_remove_zv(zv);
801 mutex_exit(&zfsdev_state_lock);
802 return (rc);
803 }
804
805 int
806 zvol_first_open(zvol_state_t *zv)
807 {
808 objset_t *os;
809 uint64_t volsize;
810 int error;
811 uint64_t readonly;
812
813 /* lie and say we're read-only */
814 error = dmu_objset_own(zv->zv_name, DMU_OST_ZVOL, B_TRUE,
815 zvol_tag, &os);
816 if (error)
817 return (error);
818
819 zv->zv_objset = os;
820 error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize);
821 if (error) {
822 ASSERT(error == 0);
823 dmu_objset_disown(os, zvol_tag);
824 return (error);
825 }
826
827 error = dmu_bonus_hold(os, ZVOL_OBJ, zvol_tag, &zv->zv_dbuf);
828 if (error) {
829 dmu_objset_disown(os, zvol_tag);
830 return (error);
831 }
832
833 zvol_size_changed(zv, volsize);
834 zv->zv_zilog = zil_open(os, zvol_get_data);
835
836 VERIFY(dsl_prop_get_integer(zv->zv_name, "readonly", &readonly,
837 NULL) == 0);
838 if (readonly || dmu_objset_is_snapshot(os) ||
839 !spa_writeable(dmu_objset_spa(os)))
840 zv->zv_flags |= ZVOL_RDONLY;
841 else
842 zv->zv_flags &= ~ZVOL_RDONLY;
843 return (error);
844 }
845
846 void
847 zvol_last_close(zvol_state_t *zv)
848 {
849 zil_close(zv->zv_zilog);
850 zv->zv_zilog = NULL;
851
852 dmu_buf_rele(zv->zv_dbuf, zvol_tag);
853 zv->zv_dbuf = NULL;
854
855 /*
856 * Evict cached data
857 */
858 if (dsl_dataset_is_dirty(dmu_objset_ds(zv->zv_objset)) &&
859 !(zv->zv_flags & ZVOL_RDONLY))
860 txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0);
861 dmu_objset_evict_dbufs(zv->zv_objset);
862
863 dmu_objset_disown(zv->zv_objset, zvol_tag);
864 zv->zv_objset = NULL;
865 }
866
867 #ifdef illumos
868 int
869 zvol_prealloc(zvol_state_t *zv)
870 {
871 objset_t *os = zv->zv_objset;
872 dmu_tx_t *tx;
873 uint64_t refd, avail, usedobjs, availobjs;
874 uint64_t resid = zv->zv_volsize;
875 uint64_t off = 0;
876
877 /* Check the space usage before attempting to allocate the space */
878 dmu_objset_space(os, &refd, &avail, &usedobjs, &availobjs);
879 if (avail < zv->zv_volsize)
880 return (SET_ERROR(ENOSPC));
881
882 /* Free old extents if they exist */
883 zvol_free_extents(zv);
884
885 while (resid != 0) {
886 int error;
887 uint64_t bytes = MIN(resid, SPA_OLD_MAXBLOCKSIZE);
888
889 tx = dmu_tx_create(os);
890 dmu_tx_hold_write(tx, ZVOL_OBJ, off, bytes);
891 error = dmu_tx_assign(tx, TXG_WAIT);
892 if (error) {
893 dmu_tx_abort(tx);
894 (void) dmu_free_long_range(os, ZVOL_OBJ, 0, off);
895 return (error);
896 }
897 dmu_prealloc(os, ZVOL_OBJ, off, bytes, tx);
898 dmu_tx_commit(tx);
899 off += bytes;
900 resid -= bytes;
901 }
902 txg_wait_synced(dmu_objset_pool(os), 0);
903
904 return (0);
905 }
906 #endif /* illumos */
907
908 static int
909 zvol_update_volsize(objset_t *os, uint64_t volsize)
910 {
911 dmu_tx_t *tx;
912 int error;
913
914 ASSERT(MUTEX_HELD(&zfsdev_state_lock));
915
916 tx = dmu_tx_create(os);
917 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL);
918 dmu_tx_mark_netfree(tx);
919 error = dmu_tx_assign(tx, TXG_WAIT);
920 if (error) {
921 dmu_tx_abort(tx);
922 return (error);
923 }
924
925 error = zap_update(os, ZVOL_ZAP_OBJ, "size", 8, 1,
926 &volsize, tx);
927 dmu_tx_commit(tx);
928
929 if (error == 0)
930 error = dmu_free_long_range(os,
931 ZVOL_OBJ, volsize, DMU_OBJECT_END);
932 return (error);
933 }
934
935 void
936 zvol_remove_minors(const char *name)
937 {
938 #ifdef illumos
939 zvol_state_t *zv;
940 char *namebuf;
941 minor_t minor;
942
943 namebuf = kmem_zalloc(strlen(name) + 2, KM_SLEEP);
944 (void) strncpy(namebuf, name, strlen(name));
945 (void) strcat(namebuf, "/");
946 mutex_enter(&zfsdev_state_lock);
947 for (minor = 1; minor <= ZFSDEV_MAX_MINOR; minor++) {
948
949 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL);
950 if (zv == NULL)
951 continue;
952 if (strncmp(namebuf, zv->zv_name, strlen(namebuf)) == 0)
953 (void) zvol_remove_zv(zv);
954 }
955 kmem_free(namebuf, strlen(name) + 2);
956
957 mutex_exit(&zfsdev_state_lock);
958 #else /* !illumos */
959 zvol_state_t *zv, *tzv;
960 size_t namelen;
961
962 namelen = strlen(name);
963
964 DROP_GIANT();
965 mutex_enter(&zfsdev_state_lock);
966
967 LIST_FOREACH_SAFE(zv, &all_zvols, zv_links, tzv) {
968 if (strcmp(zv->zv_name, name) == 0 ||
969 (strncmp(zv->zv_name, name, namelen) == 0 &&
970 strlen(zv->zv_name) > namelen && (zv->zv_name[namelen] == '/' ||
971 zv->zv_name[namelen] == '@'))) {
972 (void) zvol_remove_zv(zv);
973 }
974 }
975
976 mutex_exit(&zfsdev_state_lock);
977 PICKUP_GIANT();
978 #endif /* illumos */
979 }
980
981 static int
982 zvol_update_live_volsize(zvol_state_t *zv, uint64_t volsize)
983 {
984 uint64_t old_volsize = 0ULL;
985 int error = 0;
986
987 ASSERT(MUTEX_HELD(&zfsdev_state_lock));
988
989 /*
990 * Reinitialize the dump area to the new size. If we
991 * failed to resize the dump area then restore it back to
992 * its original size. We must set the new volsize prior
993 * to calling dumpvp_resize() to ensure that the devices'
994 * size(9P) is not visible by the dump subsystem.
995 */
996 old_volsize = zv->zv_volsize;
997 zvol_size_changed(zv, volsize);
998
999 #ifdef ZVOL_DUMP
1000 if (zv->zv_flags & ZVOL_DUMPIFIED) {
1001 if ((error = zvol_dumpify(zv)) != 0 ||
1002 (error = dumpvp_resize()) != 0) {
1003 int dumpify_error;
1004
1005 (void) zvol_update_volsize(zv->zv_objset, old_volsize);
1006 zvol_size_changed(zv, old_volsize);
1007 dumpify_error = zvol_dumpify(zv);
1008 error = dumpify_error ? dumpify_error : error;
1009 }
1010 }
1011 #endif /* ZVOL_DUMP */
1012
1013 #ifdef illumos
1014 /*
1015 * Generate a LUN expansion event.
1016 */
1017 if (error == 0) {
1018 sysevent_id_t eid;
1019 nvlist_t *attr;
1020 char *physpath = kmem_zalloc(MAXPATHLEN, KM_SLEEP);
1021
1022 (void) snprintf(physpath, MAXPATHLEN, "%s%u", ZVOL_PSEUDO_DEV,
1023 zv->zv_minor);
1024
1025 VERIFY(nvlist_alloc(&attr, NV_UNIQUE_NAME, KM_SLEEP) == 0);
1026 VERIFY(nvlist_add_string(attr, DEV_PHYS_PATH, physpath) == 0);
1027
1028 (void) ddi_log_sysevent(zfs_dip, SUNW_VENDOR, EC_DEV_STATUS,
1029 ESC_DEV_DLE, attr, &eid, DDI_SLEEP);
1030
1031 nvlist_free(attr);
1032 kmem_free(physpath, MAXPATHLEN);
1033 }
1034 #endif /* illumos */
1035 return (error);
1036 }
1037
1038 int
1039 zvol_set_volsize(const char *name, uint64_t volsize)
1040 {
1041 zvol_state_t *zv = NULL;
1042 objset_t *os;
1043 int error;
1044 dmu_object_info_t doi;
1045 uint64_t readonly;
1046 boolean_t owned = B_FALSE;
1047
1048 error = dsl_prop_get_integer(name,
1049 zfs_prop_to_name(ZFS_PROP_READONLY), &readonly, NULL);
1050 if (error != 0)
1051 return (error);
1052 if (readonly)
1053 return (SET_ERROR(EROFS));
1054
1055 mutex_enter(&zfsdev_state_lock);
1056 zv = zvol_minor_lookup(name);
1057
1058 if (zv == NULL || zv->zv_objset == NULL) {
1059 if ((error = dmu_objset_own(name, DMU_OST_ZVOL, B_FALSE,
1060 FTAG, &os)) != 0) {
1061 mutex_exit(&zfsdev_state_lock);
1062 return (error);
1063 }
1064 owned = B_TRUE;
1065 if (zv != NULL)
1066 zv->zv_objset = os;
1067 } else {
1068 os = zv->zv_objset;
1069 }
1070
1071 if ((error = dmu_object_info(os, ZVOL_OBJ, &doi)) != 0 ||
1072 (error = zvol_check_volsize(volsize, doi.doi_data_block_size)) != 0)
1073 goto out;
1074
1075 error = zvol_update_volsize(os, volsize);
1076
1077 if (error == 0 && zv != NULL)
1078 error = zvol_update_live_volsize(zv, volsize);
1079 out:
1080 if (owned) {
1081 dmu_objset_disown(os, FTAG);
1082 if (zv != NULL)
1083 zv->zv_objset = NULL;
1084 }
1085 mutex_exit(&zfsdev_state_lock);
1086 return (error);
1087 }
1088
1089 /*ARGSUSED*/
1090 #ifdef illumos
1091 int
1092 zvol_open(dev_t *devp, int flag, int otyp, cred_t *cr)
1093 #else
1094 static int
1095 zvol_open(struct g_provider *pp, int flag, int count)
1096 #endif
1097 {
1098 zvol_state_t *zv;
1099 int err = 0;
1100 #ifdef illumos
1101
1102 mutex_enter(&zfsdev_state_lock);
1103
1104 zv = zfsdev_get_soft_state(getminor(*devp), ZSST_ZVOL);
1105 if (zv == NULL) {
1106 mutex_exit(&zfsdev_state_lock);
1107 return (SET_ERROR(ENXIO));
1108 }
1109
1110 if (zv->zv_total_opens == 0)
1111 err = zvol_first_open(zv);
1112 if (err) {
1113 mutex_exit(&zfsdev_state_lock);
1114 return (err);
1115 }
1116 #else /* !illumos */
1117 boolean_t locked = B_FALSE;
1118
1119 /*
1120 * Protect against recursively entering spa_namespace_lock
1121 * when spa_open() is used for a pool on a (local) ZVOL(s).
1122 * This is needed since we replaced upstream zfsdev_state_lock
1123 * with spa_namespace_lock in the ZVOL code.
1124 * We are using the same trick as spa_open().
1125 * Note that calls in zvol_first_open which need to resolve
1126 * pool name to a spa object will enter spa_open()
1127 * recursively, but that function already has all the
1128 * necessary protection.
1129 */
1130 if (!MUTEX_HELD(&zfsdev_state_lock)) {
1131 mutex_enter(&zfsdev_state_lock);
1132 locked = B_TRUE;
1133 }
1134
1135 zv = pp->private;
1136 if (zv == NULL) {
1137 if (locked)
1138 mutex_exit(&zfsdev_state_lock);
1139 return (SET_ERROR(ENXIO));
1140 }
1141
1142 if (zv->zv_total_opens == 0) {
1143 err = zvol_first_open(zv);
1144 if (err) {
1145 if (locked)
1146 mutex_exit(&zfsdev_state_lock);
1147 return (err);
1148 }
1149 pp->mediasize = zv->zv_volsize;
1150 pp->stripeoffset = 0;
1151 pp->stripesize = zv->zv_volblocksize;
1152 }
1153 #endif /* illumos */
1154 if ((flag & FWRITE) && (zv->zv_flags & ZVOL_RDONLY)) {
1155 err = SET_ERROR(EROFS);
1156 goto out;
1157 }
1158 if (zv->zv_flags & ZVOL_EXCL) {
1159 err = SET_ERROR(EBUSY);
1160 goto out;
1161 }
1162 #ifdef FEXCL
1163 if (flag & FEXCL) {
1164 if (zv->zv_total_opens != 0) {
1165 err = SET_ERROR(EBUSY);
1166 goto out;
1167 }
1168 zv->zv_flags |= ZVOL_EXCL;
1169 }
1170 #endif
1171
1172 #ifdef illumos
1173 if (zv->zv_open_count[otyp] == 0 || otyp == OTYP_LYR) {
1174 zv->zv_open_count[otyp]++;
1175 zv->zv_total_opens++;
1176 }
1177 mutex_exit(&zfsdev_state_lock);
1178 #else
1179 zv->zv_total_opens += count;
1180 if (locked)
1181 mutex_exit(&zfsdev_state_lock);
1182 #endif
1183
1184 return (err);
1185 out:
1186 if (zv->zv_total_opens == 0)
1187 zvol_last_close(zv);
1188 #ifdef illumos
1189 mutex_exit(&zfsdev_state_lock);
1190 #else
1191 if (locked)
1192 mutex_exit(&zfsdev_state_lock);
1193 #endif
1194 return (err);
1195 }
1196
1197 /*ARGSUSED*/
1198 #ifdef illumos
1199 int
1200 zvol_close(dev_t dev, int flag, int otyp, cred_t *cr)
1201 {
1202 minor_t minor = getminor(dev);
1203 zvol_state_t *zv;
1204 int error = 0;
1205
1206 mutex_enter(&zfsdev_state_lock);
1207
1208 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL);
1209 if (zv == NULL) {
1210 mutex_exit(&zfsdev_state_lock);
1211 #else /* !illumos */
1212 static int
1213 zvol_close(struct g_provider *pp, int flag, int count)
1214 {
1215 zvol_state_t *zv;
1216 int error = 0;
1217 boolean_t locked = B_FALSE;
1218
1219 /* See comment in zvol_open(). */
1220 if (!MUTEX_HELD(&zfsdev_state_lock)) {
1221 mutex_enter(&zfsdev_state_lock);
1222 locked = B_TRUE;
1223 }
1224
1225 zv = pp->private;
1226 if (zv == NULL) {
1227 if (locked)
1228 mutex_exit(&zfsdev_state_lock);
1229 #endif /* illumos */
1230 return (SET_ERROR(ENXIO));
1231 }
1232
1233 if (zv->zv_flags & ZVOL_EXCL) {
1234 ASSERT(zv->zv_total_opens == 1);
1235 zv->zv_flags &= ~ZVOL_EXCL;
1236 }
1237
1238 /*
1239 * If the open count is zero, this is a spurious close.
1240 * That indicates a bug in the kernel / DDI framework.
1241 */
1242 #ifdef illumos
1243 ASSERT(zv->zv_open_count[otyp] != 0);
1244 #endif
1245 ASSERT(zv->zv_total_opens != 0);
1246
1247 /*
1248 * You may get multiple opens, but only one close.
1249 */
1250 #ifdef illumos
1251 zv->zv_open_count[otyp]--;
1252 zv->zv_total_opens--;
1253 #else
1254 zv->zv_total_opens -= count;
1255 #endif
1256
1257 if (zv->zv_total_opens == 0)
1258 zvol_last_close(zv);
1259
1260 #ifdef illumos
1261 mutex_exit(&zfsdev_state_lock);
1262 #else
1263 if (locked)
1264 mutex_exit(&zfsdev_state_lock);
1265 #endif
1266 return (error);
1267 }
1268
1269 static void
1270 zvol_get_done(zgd_t *zgd, int error)
1271 {
1272 if (zgd->zgd_db)
1273 dmu_buf_rele(zgd->zgd_db, zgd);
1274
1275 zfs_range_unlock(zgd->zgd_rl);
1276
1277 if (error == 0 && zgd->zgd_bp)
1278 zil_add_block(zgd->zgd_zilog, zgd->zgd_bp);
1279
1280 kmem_free(zgd, sizeof (zgd_t));
1281 }
1282
1283 /*
1284 * Get data to generate a TX_WRITE intent log record.
1285 */
1286 static int
1287 zvol_get_data(void *arg, lr_write_t *lr, char *buf, zio_t *zio)
1288 {
1289 zvol_state_t *zv = arg;
1290 objset_t *os = zv->zv_objset;
1291 uint64_t object = ZVOL_OBJ;
1292 uint64_t offset = lr->lr_offset;
1293 uint64_t size = lr->lr_length; /* length of user data */
1294 blkptr_t *bp = &lr->lr_blkptr;
1295 dmu_buf_t *db;
1296 zgd_t *zgd;
1297 int error;
1298
1299 ASSERT(zio != NULL);
1300 ASSERT(size != 0);
1301
1302 zgd = kmem_zalloc(sizeof (zgd_t), KM_SLEEP);
1303 zgd->zgd_zilog = zv->zv_zilog;
1304 zgd->zgd_rl = zfs_range_lock(&zv->zv_znode, offset, size, RL_READER);
1305
1306 /*
1307 * Write records come in two flavors: immediate and indirect.
1308 * For small writes it's cheaper to store the data with the
1309 * log record (immediate); for large writes it's cheaper to
1310 * sync the data and get a pointer to it (indirect) so that
1311 * we don't have to write the data twice.
1312 */
1313 if (buf != NULL) { /* immediate write */
1314 error = dmu_read(os, object, offset, size, buf,
1315 DMU_READ_NO_PREFETCH);
1316 } else {
1317 size = zv->zv_volblocksize;
1318 offset = P2ALIGN(offset, size);
1319 error = dmu_buf_hold(os, object, offset, zgd, &db,
1320 DMU_READ_NO_PREFETCH);
1321 if (error == 0) {
1322 blkptr_t *obp = dmu_buf_get_blkptr(db);
1323 if (obp) {
1324 ASSERT(BP_IS_HOLE(bp));
1325 *bp = *obp;
1326 }
1327
1328 zgd->zgd_db = db;
1329 zgd->zgd_bp = bp;
1330
1331 ASSERT(db->db_offset == offset);
1332 ASSERT(db->db_size == size);
1333
1334 error = dmu_sync(zio, lr->lr_common.lrc_txg,
1335 zvol_get_done, zgd);
1336
1337 if (error == 0)
1338 return (0);
1339 }
1340 }
1341
1342 zvol_get_done(zgd, error);
1343
1344 return (error);
1345 }
1346
1347 /*
1348 * zvol_log_write() handles synchronous writes using TX_WRITE ZIL transactions.
1349 *
1350 * We store data in the log buffers if it's small enough.
1351 * Otherwise we will later flush the data out via dmu_sync().
1352 */
1353 ssize_t zvol_immediate_write_sz = 32768;
1354
1355 static void
1356 zvol_log_write(zvol_state_t *zv, dmu_tx_t *tx, offset_t off, ssize_t resid,
1357 boolean_t sync)
1358 {
1359 uint32_t blocksize = zv->zv_volblocksize;
1360 zilog_t *zilog = zv->zv_zilog;
1361 boolean_t slogging;
1362 ssize_t immediate_write_sz;
1363
1364 if (zil_replaying(zilog, tx))
1365 return;
1366
1367 immediate_write_sz = (zilog->zl_logbias == ZFS_LOGBIAS_THROUGHPUT)
1368 ? 0 : zvol_immediate_write_sz;
1369
1370 slogging = spa_has_slogs(zilog->zl_spa) &&
1371 (zilog->zl_logbias == ZFS_LOGBIAS_LATENCY);
1372
1373 while (resid) {
1374 itx_t *itx;
1375 lr_write_t *lr;
1376 ssize_t len;
1377 itx_wr_state_t write_state;
1378
1379 /*
1380 * Unlike zfs_log_write() we can be called with
1381 * upto DMU_MAX_ACCESS/2 (5MB) writes.
1382 */
1383 if (blocksize > immediate_write_sz && !slogging &&
1384 resid >= blocksize && off % blocksize == 0) {
1385 write_state = WR_INDIRECT; /* uses dmu_sync */
1386 len = blocksize;
1387 } else if (sync) {
1388 write_state = WR_COPIED;
1389 len = MIN(ZIL_MAX_LOG_DATA, resid);
1390 } else {
1391 write_state = WR_NEED_COPY;
1392 len = MIN(ZIL_MAX_LOG_DATA, resid);
1393 }
1394
1395 itx = zil_itx_create(TX_WRITE, sizeof (*lr) +
1396 (write_state == WR_COPIED ? len : 0));
1397 lr = (lr_write_t *)&itx->itx_lr;
1398 if (write_state == WR_COPIED && dmu_read(zv->zv_objset,
1399 ZVOL_OBJ, off, len, lr + 1, DMU_READ_NO_PREFETCH) != 0) {
1400 zil_itx_destroy(itx);
1401 itx = zil_itx_create(TX_WRITE, sizeof (*lr));
1402 lr = (lr_write_t *)&itx->itx_lr;
1403 write_state = WR_NEED_COPY;
1404 }
1405
1406 itx->itx_wr_state = write_state;
1407 if (write_state == WR_NEED_COPY)
1408 itx->itx_sod += len;
1409 lr->lr_foid = ZVOL_OBJ;
1410 lr->lr_offset = off;
1411 lr->lr_length = len;
1412 lr->lr_blkoff = 0;
1413 BP_ZERO(&lr->lr_blkptr);
1414
1415 itx->itx_private = zv;
1416 itx->itx_sync = sync;
1417
1418 zil_itx_assign(zilog, itx, tx);
1419
1420 off += len;
1421 resid -= len;
1422 }
1423 }
1424
1425 #ifdef illumos
1426 static int
1427 zvol_dumpio_vdev(vdev_t *vd, void *addr, uint64_t offset, uint64_t origoffset,
1428 uint64_t size, boolean_t doread, boolean_t isdump)
1429 {
1430 vdev_disk_t *dvd;
1431 int c;
1432 int numerrors = 0;
1433
1434 if (vd->vdev_ops == &vdev_mirror_ops ||
1435 vd->vdev_ops == &vdev_replacing_ops ||
1436 vd->vdev_ops == &vdev_spare_ops) {
1437 for (c = 0; c < vd->vdev_children; c++) {
1438 int err = zvol_dumpio_vdev(vd->vdev_child[c],
1439 addr, offset, origoffset, size, doread, isdump);
1440 if (err != 0) {
1441 numerrors++;
1442 } else if (doread) {
1443 break;
1444 }
1445 }
1446 }
1447
1448 if (!vd->vdev_ops->vdev_op_leaf && vd->vdev_ops != &vdev_raidz_ops)
1449 return (numerrors < vd->vdev_children ? 0 : EIO);
1450
1451 if (doread && !vdev_readable(vd))
1452 return (SET_ERROR(EIO));
1453 else if (!doread && !vdev_writeable(vd))
1454 return (SET_ERROR(EIO));
1455
1456 if (vd->vdev_ops == &vdev_raidz_ops) {
1457 return (vdev_raidz_physio(vd,
1458 addr, size, offset, origoffset, doread, isdump));
1459 }
1460
1461 offset += VDEV_LABEL_START_SIZE;
1462
1463 if (ddi_in_panic() || isdump) {
1464 ASSERT(!doread);
1465 if (doread)
1466 return (SET_ERROR(EIO));
1467 dvd = vd->vdev_tsd;
1468 ASSERT3P(dvd, !=, NULL);
1469 return (ldi_dump(dvd->vd_lh, addr, lbtodb(offset),
1470 lbtodb(size)));
1471 } else {
1472 dvd = vd->vdev_tsd;
1473 ASSERT3P(dvd, !=, NULL);
1474 return (vdev_disk_ldi_physio(dvd->vd_lh, addr, size,
1475 offset, doread ? B_READ : B_WRITE));
1476 }
1477 }
1478
1479 static int
1480 zvol_dumpio(zvol_state_t *zv, void *addr, uint64_t offset, uint64_t size,
1481 boolean_t doread, boolean_t isdump)
1482 {
1483 vdev_t *vd;
1484 int error;
1485 zvol_extent_t *ze;
1486 spa_t *spa = dmu_objset_spa(zv->zv_objset);
1487
1488 /* Must be sector aligned, and not stradle a block boundary. */
1489 if (P2PHASE(offset, DEV_BSIZE) || P2PHASE(size, DEV_BSIZE) ||
1490 P2BOUNDARY(offset, size, zv->zv_volblocksize)) {
1491 return (SET_ERROR(EINVAL));
1492 }
1493 ASSERT(size <= zv->zv_volblocksize);
1494
1495 /* Locate the extent this belongs to */
1496 ze = list_head(&zv->zv_extents);
1497 while (offset >= ze->ze_nblks * zv->zv_volblocksize) {
1498 offset -= ze->ze_nblks * zv->zv_volblocksize;
1499 ze = list_next(&zv->zv_extents, ze);
1500 }
1501
1502 if (ze == NULL)
1503 return (SET_ERROR(EINVAL));
1504
1505 if (!ddi_in_panic())
1506 spa_config_enter(spa, SCL_STATE, FTAG, RW_READER);
1507
1508 vd = vdev_lookup_top(spa, DVA_GET_VDEV(&ze->ze_dva));
1509 offset += DVA_GET_OFFSET(&ze->ze_dva);
1510 error = zvol_dumpio_vdev(vd, addr, offset, DVA_GET_OFFSET(&ze->ze_dva),
1511 size, doread, isdump);
1512
1513 if (!ddi_in_panic())
1514 spa_config_exit(spa, SCL_STATE, FTAG);
1515
1516 return (error);
1517 }
1518
1519 int
1520 zvol_strategy(buf_t *bp)
1521 {
1522 zfs_soft_state_t *zs = NULL;
1523 #else /* !illumos */
1524 void
1525 zvol_strategy(struct bio *bp)
1526 {
1527 #endif /* illumos */
1528 zvol_state_t *zv;
1529 uint64_t off, volsize;
1530 size_t resid;
1531 char *addr;
1532 objset_t *os;
1533 rl_t *rl;
1534 int error = 0;
1535 #ifdef illumos
1536 boolean_t doread = bp->b_flags & B_READ;
1537 #else
1538 boolean_t doread = 0;
1539 #endif
1540 boolean_t is_dumpified;
1541 boolean_t sync;
1542
1543 #ifdef illumos
1544 if (getminor(bp->b_edev) == 0) {
1545 error = SET_ERROR(EINVAL);
1546 } else {
1547 zs = ddi_get_soft_state(zfsdev_state, getminor(bp->b_edev));
1548 if (zs == NULL)
1549 error = SET_ERROR(ENXIO);
1550 else if (zs->zss_type != ZSST_ZVOL)
1551 error = SET_ERROR(EINVAL);
1552 }
1553
1554 if (error) {
1555 bioerror(bp, error);
1556 biodone(bp);
1557 return (0);
1558 }
1559
1560 zv = zs->zss_data;
1561
1562 if (!(bp->b_flags & B_READ) && (zv->zv_flags & ZVOL_RDONLY)) {
1563 bioerror(bp, EROFS);
1564 biodone(bp);
1565 return (0);
1566 }
1567
1568 off = ldbtob(bp->b_blkno);
1569 #else /* !illumos */
1570 if (bp->bio_to)
1571 zv = bp->bio_to->private;
1572 else
1573 zv = bp->bio_dev->si_drv2;
1574
1575 if (zv == NULL) {
1576 error = SET_ERROR(ENXIO);
1577 goto out;
1578 }
1579
1580 if (bp->bio_cmd != BIO_READ && (zv->zv_flags & ZVOL_RDONLY)) {
1581 error = SET_ERROR(EROFS);
1582 goto out;
1583 }
1584
1585 switch (bp->bio_cmd) {
1586 case BIO_FLUSH:
1587 goto sync;
1588 case BIO_READ:
1589 doread = 1;
1590 case BIO_WRITE:
1591 case BIO_DELETE:
1592 break;
1593 default:
1594 error = EOPNOTSUPP;
1595 goto out;
1596 }
1597
1598 off = bp->bio_offset;
1599 #endif /* illumos */
1600 volsize = zv->zv_volsize;
1601
1602 os = zv->zv_objset;
1603 ASSERT(os != NULL);
1604
1605 #ifdef illumos
1606 bp_mapin(bp);
1607 addr = bp->b_un.b_addr;
1608 resid = bp->b_bcount;
1609
1610 if (resid > 0 && (off < 0 || off >= volsize)) {
1611 bioerror(bp, EIO);
1612 biodone(bp);
1613 return (0);
1614 }
1615
1616 is_dumpified = zv->zv_flags & ZVOL_DUMPIFIED;
1617 sync = ((!(bp->b_flags & B_ASYNC) &&
1618 !(zv->zv_flags & ZVOL_WCE)) ||
1619 (zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS)) &&
1620 !doread && !is_dumpified;
1621 #else /* !illumos */
1622 addr = bp->bio_data;
1623 resid = bp->bio_length;
1624
1625 if (resid > 0 && (off < 0 || off >= volsize)) {
1626 error = SET_ERROR(EIO);
1627 goto out;
1628 }
1629
1630 is_dumpified = B_FALSE;
1631 sync = !doread && !is_dumpified &&
1632 zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS;
1633 #endif /* illumos */
1634
1635 /*
1636 * There must be no buffer changes when doing a dmu_sync() because
1637 * we can't change the data whilst calculating the checksum.
1638 */
1639 rl = zfs_range_lock(&zv->zv_znode, off, resid,
1640 doread ? RL_READER : RL_WRITER);
1641
1642 #ifndef illumos
1643 if (bp->bio_cmd == BIO_DELETE) {
1644 dmu_tx_t *tx = dmu_tx_create(zv->zv_objset);
1645 error = dmu_tx_assign(tx, TXG_WAIT);
1646 if (error != 0) {
1647 dmu_tx_abort(tx);
1648 } else {
1649 zvol_log_truncate(zv, tx, off, resid, B_TRUE);
1650 dmu_tx_commit(tx);
1651 error = dmu_free_long_range(zv->zv_objset, ZVOL_OBJ,
1652 off, resid);
1653 resid = 0;
1654 }
1655 goto unlock;
1656 }
1657 #endif
1658 while (resid != 0 && off < volsize) {
1659 size_t size = MIN(resid, zvol_maxphys);
1660 #ifdef illumos
1661 if (is_dumpified) {
1662 size = MIN(size, P2END(off, zv->zv_volblocksize) - off);
1663 error = zvol_dumpio(zv, addr, off, size,
1664 doread, B_FALSE);
1665 } else if (doread) {
1666 #else
1667 if (doread) {
1668 #endif
1669 error = dmu_read(os, ZVOL_OBJ, off, size, addr,
1670 DMU_READ_PREFETCH);
1671 } else {
1672 dmu_tx_t *tx = dmu_tx_create(os);
1673 dmu_tx_hold_write(tx, ZVOL_OBJ, off, size);
1674 error = dmu_tx_assign(tx, TXG_WAIT);
1675 if (error) {
1676 dmu_tx_abort(tx);
1677 } else {
1678 dmu_write(os, ZVOL_OBJ, off, size, addr, tx);
1679 zvol_log_write(zv, tx, off, size, sync);
1680 dmu_tx_commit(tx);
1681 }
1682 }
1683 if (error) {
1684 /* convert checksum errors into IO errors */
1685 if (error == ECKSUM)
1686 error = SET_ERROR(EIO);
1687 break;
1688 }
1689 off += size;
1690 addr += size;
1691 resid -= size;
1692 }
1693 #ifndef illumos
1694 unlock:
1695 #endif
1696 zfs_range_unlock(rl);
1697
1698 #ifdef illumos
1699 if ((bp->b_resid = resid) == bp->b_bcount)
1700 bioerror(bp, off > volsize ? EINVAL : error);
1701
1702 if (sync)
1703 zil_commit(zv->zv_zilog, ZVOL_OBJ);
1704 biodone(bp);
1705
1706 return (0);
1707 #else /* !illumos */
1708 bp->bio_completed = bp->bio_length - resid;
1709 if (bp->bio_completed < bp->bio_length && off > volsize)
1710 error = EINVAL;
1711
1712 if (sync) {
1713 sync:
1714 zil_commit(zv->zv_zilog, ZVOL_OBJ);
1715 }
1716 out:
1717 if (bp->bio_to)
1718 g_io_deliver(bp, error);
1719 else
1720 biofinish(bp, NULL, error);
1721 #endif /* illumos */
1722 }
1723
1724 #ifdef illumos
1725 /*
1726 * Set the buffer count to the zvol maximum transfer.
1727 * Using our own routine instead of the default minphys()
1728 * means that for larger writes we write bigger buffers on X86
1729 * (128K instead of 56K) and flush the disk write cache less often
1730 * (every zvol_maxphys - currently 1MB) instead of minphys (currently
1731 * 56K on X86 and 128K on sparc).
1732 */
1733 void
1734 zvol_minphys(struct buf *bp)
1735 {
1736 if (bp->b_bcount > zvol_maxphys)
1737 bp->b_bcount = zvol_maxphys;
1738 }
1739
1740 int
1741 zvol_dump(dev_t dev, caddr_t addr, daddr_t blkno, int nblocks)
1742 {
1743 minor_t minor = getminor(dev);
1744 zvol_state_t *zv;
1745 int error = 0;
1746 uint64_t size;
1747 uint64_t boff;
1748 uint64_t resid;
1749
1750 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL);
1751 if (zv == NULL)
1752 return (SET_ERROR(ENXIO));
1753
1754 if ((zv->zv_flags & ZVOL_DUMPIFIED) == 0)
1755 return (SET_ERROR(EINVAL));
1756
1757 boff = ldbtob(blkno);
1758 resid = ldbtob(nblocks);
1759
1760 VERIFY3U(boff + resid, <=, zv->zv_volsize);
1761
1762 while (resid) {
1763 size = MIN(resid, P2END(boff, zv->zv_volblocksize) - boff);
1764 error = zvol_dumpio(zv, addr, boff, size, B_FALSE, B_TRUE);
1765 if (error)
1766 break;
1767 boff += size;
1768 addr += size;
1769 resid -= size;
1770 }
1771
1772 return (error);
1773 }
1774
1775 /*ARGSUSED*/
1776 int
1777 zvol_read(dev_t dev, uio_t *uio, cred_t *cr)
1778 {
1779 minor_t minor = getminor(dev);
1780 #else /* !illumos */
1781 int
1782 zvol_read(struct cdev *dev, struct uio *uio, int ioflag)
1783 {
1784 #endif /* illumos */
1785 zvol_state_t *zv;
1786 uint64_t volsize;
1787 rl_t *rl;
1788 int error = 0;
1789
1790 #ifdef illumos
1791 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL);
1792 if (zv == NULL)
1793 return (SET_ERROR(ENXIO));
1794 #else
1795 zv = dev->si_drv2;
1796 #endif
1797
1798 volsize = zv->zv_volsize;
1799 /* uio_loffset == volsize isn't an error as its required for EOF processing. */
1800 if (uio->uio_resid > 0 &&
1801 (uio->uio_loffset < 0 || uio->uio_loffset > volsize))
1802 return (SET_ERROR(EIO));
1803
1804 #ifdef illumos
1805 if (zv->zv_flags & ZVOL_DUMPIFIED) {
1806 error = physio(zvol_strategy, NULL, dev, B_READ,
1807 zvol_minphys, uio);
1808 return (error);
1809 }
1810 #endif
1811
1812 rl = zfs_range_lock(&zv->zv_znode, uio->uio_loffset, uio->uio_resid,
1813 RL_READER);
1814 while (uio->uio_resid > 0 && uio->uio_loffset < volsize) {
1815 uint64_t bytes = MIN(uio->uio_resid, DMU_MAX_ACCESS >> 1);
1816
1817 /* don't read past the end */
1818 if (bytes > volsize - uio->uio_loffset)
1819 bytes = volsize - uio->uio_loffset;
1820
1821 error = dmu_read_uio_dbuf(zv->zv_dbuf, uio, bytes);
1822 if (error) {
1823 /* convert checksum errors into IO errors */
1824 if (error == ECKSUM)
1825 error = SET_ERROR(EIO);
1826 break;
1827 }
1828 }
1829 zfs_range_unlock(rl);
1830 return (error);
1831 }
1832
1833 #ifdef illumos
1834 /*ARGSUSED*/
1835 int
1836 zvol_write(dev_t dev, uio_t *uio, cred_t *cr)
1837 {
1838 minor_t minor = getminor(dev);
1839 #else /* !illumos */
1840 int
1841 zvol_write(struct cdev *dev, struct uio *uio, int ioflag)
1842 {
1843 #endif /* illumos */
1844 zvol_state_t *zv;
1845 uint64_t volsize;
1846 rl_t *rl;
1847 int error = 0;
1848 boolean_t sync;
1849
1850 #ifdef illumos
1851 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL);
1852 if (zv == NULL)
1853 return (SET_ERROR(ENXIO));
1854 #else
1855 zv = dev->si_drv2;
1856 #endif
1857
1858 volsize = zv->zv_volsize;
1859 /* uio_loffset == volsize isn't an error as its required for EOF processing. */
1860 if (uio->uio_resid > 0 &&
1861 (uio->uio_loffset < 0 || uio->uio_loffset > volsize))
1862 return (SET_ERROR(EIO));
1863
1864 #ifdef illumos
1865 if (zv->zv_flags & ZVOL_DUMPIFIED) {
1866 error = physio(zvol_strategy, NULL, dev, B_WRITE,
1867 zvol_minphys, uio);
1868 return (error);
1869 }
1870
1871 sync = !(zv->zv_flags & ZVOL_WCE) ||
1872 #else
1873 sync = (ioflag & IO_SYNC) ||
1874 #endif
1875 (zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS);
1876
1877 rl = zfs_range_lock(&zv->zv_znode, uio->uio_loffset, uio->uio_resid,
1878 RL_WRITER);
1879 while (uio->uio_resid > 0 && uio->uio_loffset < volsize) {
1880 uint64_t bytes = MIN(uio->uio_resid, DMU_MAX_ACCESS >> 1);
1881 uint64_t off = uio->uio_loffset;
1882 dmu_tx_t *tx = dmu_tx_create(zv->zv_objset);
1883
1884 if (bytes > volsize - off) /* don't write past the end */
1885 bytes = volsize - off;
1886
1887 dmu_tx_hold_write(tx, ZVOL_OBJ, off, bytes);
1888 error = dmu_tx_assign(tx, TXG_WAIT);
1889 if (error) {
1890 dmu_tx_abort(tx);
1891 break;
1892 }
1893 error = dmu_write_uio_dbuf(zv->zv_dbuf, uio, bytes, tx);
1894 if (error == 0)
1895 zvol_log_write(zv, tx, off, bytes, sync);
1896 dmu_tx_commit(tx);
1897
1898 if (error)
1899 break;
1900 }
1901 zfs_range_unlock(rl);
1902 if (sync)
1903 zil_commit(zv->zv_zilog, ZVOL_OBJ);
1904 return (error);
1905 }
1906
1907 #ifdef illumos
1908 int
1909 zvol_getefi(void *arg, int flag, uint64_t vs, uint8_t bs)
1910 {
1911 struct uuid uuid = EFI_RESERVED;
1912 efi_gpe_t gpe = { 0 };
1913 uint32_t crc;
1914 dk_efi_t efi;
1915 int length;
1916 char *ptr;
1917
1918 if (ddi_copyin(arg, &efi, sizeof (dk_efi_t), flag))
1919 return (SET_ERROR(EFAULT));
1920 ptr = (char *)(uintptr_t)efi.dki_data_64;
1921 length = efi.dki_length;
1922 /*
1923 * Some clients may attempt to request a PMBR for the
1924 * zvol. Currently this interface will return EINVAL to
1925 * such requests. These requests could be supported by
1926 * adding a check for lba == 0 and consing up an appropriate
1927 * PMBR.
1928 */
1929 if (efi.dki_lba < 1 || efi.dki_lba > 2 || length <= 0)
1930 return (SET_ERROR(EINVAL));
1931
1932 gpe.efi_gpe_StartingLBA = LE_64(34ULL);
1933 gpe.efi_gpe_EndingLBA = LE_64((vs >> bs) - 1);
1934 UUID_LE_CONVERT(gpe.efi_gpe_PartitionTypeGUID, uuid);
1935
1936 if (efi.dki_lba == 1) {
1937 efi_gpt_t gpt = { 0 };
1938
1939 gpt.efi_gpt_Signature = LE_64(EFI_SIGNATURE);
1940 gpt.efi_gpt_Revision = LE_32(EFI_VERSION_CURRENT);
1941 gpt.efi_gpt_HeaderSize = LE_32(sizeof (gpt));
1942 gpt.efi_gpt_MyLBA = LE_64(1ULL);
1943 gpt.efi_gpt_FirstUsableLBA = LE_64(34ULL);
1944 gpt.efi_gpt_LastUsableLBA = LE_64((vs >> bs) - 1);
1945 gpt.efi_gpt_PartitionEntryLBA = LE_64(2ULL);
1946 gpt.efi_gpt_NumberOfPartitionEntries = LE_32(1);
1947 gpt.efi_gpt_SizeOfPartitionEntry =
1948 LE_32(sizeof (efi_gpe_t));
1949 CRC32(crc, &gpe, sizeof (gpe), -1U, crc32_table);
1950 gpt.efi_gpt_PartitionEntryArrayCRC32 = LE_32(~crc);
1951 CRC32(crc, &gpt, sizeof (gpt), -1U, crc32_table);
1952 gpt.efi_gpt_HeaderCRC32 = LE_32(~crc);
1953 if (ddi_copyout(&gpt, ptr, MIN(sizeof (gpt), length),
1954 flag))
1955 return (SET_ERROR(EFAULT));
1956 ptr += sizeof (gpt);
1957 length -= sizeof (gpt);
1958 }
1959 if (length > 0 && ddi_copyout(&gpe, ptr, MIN(sizeof (gpe),
1960 length), flag))
1961 return (SET_ERROR(EFAULT));
1962 return (0);
1963 }
1964
1965 /*
1966 * BEGIN entry points to allow external callers access to the volume.
1967 */
1968 /*
1969 * Return the volume parameters needed for access from an external caller.
1970 * These values are invariant as long as the volume is held open.
1971 */
1972 int
1973 zvol_get_volume_params(minor_t minor, uint64_t *blksize,
1974 uint64_t *max_xfer_len, void **minor_hdl, void **objset_hdl, void **zil_hdl,
1975 void **rl_hdl, void **bonus_hdl)
1976 {
1977 zvol_state_t *zv;
1978
1979 zv = zfsdev_get_soft_state(minor, ZSST_ZVOL);
1980 if (zv == NULL)
1981 return (SET_ERROR(ENXIO));
1982 if (zv->zv_flags & ZVOL_DUMPIFIED)
1983 return (SET_ERROR(ENXIO));
1984
1985 ASSERT(blksize && max_xfer_len && minor_hdl &&
1986 objset_hdl && zil_hdl && rl_hdl && bonus_hdl);
1987
1988 *blksize = zv->zv_volblocksize;
1989 *max_xfer_len = (uint64_t)zvol_maxphys;
1990 *minor_hdl = zv;
1991 *objset_hdl = zv->zv_objset;
1992 *zil_hdl = zv->zv_zilog;
1993 *rl_hdl = &zv->zv_znode;
1994 *bonus_hdl = zv->zv_dbuf;
1995 return (0);
1996 }
1997
1998 /*
1999 * Return the current volume size to an external caller.
2000 * The size can change while the volume is open.
2001 */
2002 uint64_t
2003 zvol_get_volume_size(void *minor_hdl)
2004 {
2005 zvol_state_t *zv = minor_hdl;
2006
2007 return (zv->zv_volsize);
2008 }
2009
2010 /*
2011 * Return the current WCE setting to an external caller.
2012 * The WCE setting can change while the volume is open.
2013 */
2014 int
2015 zvol_get_volume_wce(void *minor_hdl)
2016 {
2017 zvol_state_t *zv = minor_hdl;
2018
2019 return ((zv->zv_flags & ZVOL_WCE) ? 1 : 0);
2020 }
2021
2022 /*
2023 * Entry point for external callers to zvol_log_write
2024 */
2025 void
2026 zvol_log_write_minor(void *minor_hdl, dmu_tx_t *tx, offset_t off, ssize_t resid,
2027 boolean_t sync)
2028 {
2029 zvol_state_t *zv = minor_hdl;
2030
2031 zvol_log_write(zv, tx, off, resid, sync);
2032 }
2033 /*
2034 * END entry points to allow external callers access to the volume.
2035 */
2036 #endif /* illumos */
2037
2038 /*
2039 * Log a DKIOCFREE/free-long-range to the ZIL with TX_TRUNCATE.
2040 */
2041 static void
2042 zvol_log_truncate(zvol_state_t *zv, dmu_tx_t *tx, uint64_t off, uint64_t len,
2043 boolean_t sync)
2044 {
2045 itx_t *itx;
2046 lr_truncate_t *lr;
2047 zilog_t *zilog = zv->zv_zilog;
2048
2049 if (zil_replaying(zilog, tx))
2050 return;
2051
2052 itx = zil_itx_create(TX_TRUNCATE, sizeof (*lr));
2053 lr = (lr_truncate_t *)&itx->itx_lr;
2054 lr->lr_foid = ZVOL_OBJ;
2055 lr->lr_offset = off;
2056 lr->lr_length = len;
2057
2058 itx->itx_sync = sync;
2059 zil_itx_assign(zilog, itx, tx);
2060 }
2061
2062 #ifdef illumos
2063 /*
2064 * Dirtbag ioctls to support mkfs(1M) for UFS filesystems. See dkio(7I).
2065 * Also a dirtbag dkio ioctl for unmap/free-block functionality.
2066 */
2067 /*ARGSUSED*/
2068 int
2069 zvol_ioctl(dev_t dev, int cmd, intptr_t arg, int flag, cred_t *cr, int *rvalp)
2070 {
2071 zvol_state_t *zv;
2072 struct dk_callback *dkc;
2073 int error = 0;
2074 rl_t *rl;
2075
2076 mutex_enter(&zfsdev_state_lock);
2077
2078 zv = zfsdev_get_soft_state(getminor(dev), ZSST_ZVOL);
2079
2080 if (zv == NULL) {
2081 mutex_exit(&zfsdev_state_lock);
2082 return (SET_ERROR(ENXIO));
2083 }
2084 ASSERT(zv->zv_total_opens > 0);
2085
2086 switch (cmd) {
2087
2088 case DKIOCINFO:
2089 {
2090 struct dk_cinfo dki;
2091
2092 bzero(&dki, sizeof (dki));
2093 (void) strcpy(dki.dki_cname, "zvol");
2094 (void) strcpy(dki.dki_dname, "zvol");
2095 dki.dki_ctype = DKC_UNKNOWN;
2096 dki.dki_unit = getminor(dev);
2097 dki.dki_maxtransfer =
2098 1 << (SPA_OLD_MAXBLOCKSHIFT - zv->zv_min_bs);
2099 mutex_exit(&zfsdev_state_lock);
2100 if (ddi_copyout(&dki, (void *)arg, sizeof (dki), flag))
2101 error = SET_ERROR(EFAULT);
2102 return (error);
2103 }
2104
2105 case DKIOCGMEDIAINFO:
2106 {
2107 struct dk_minfo dkm;
2108
2109 bzero(&dkm, sizeof (dkm));
2110 dkm.dki_lbsize = 1U << zv->zv_min_bs;
2111 dkm.dki_capacity = zv->zv_volsize >> zv->zv_min_bs;
2112 dkm.dki_media_type = DK_UNKNOWN;
2113 mutex_exit(&zfsdev_state_lock);
2114 if (ddi_copyout(&dkm, (void *)arg, sizeof (dkm), flag))
2115 error = SET_ERROR(EFAULT);
2116 return (error);
2117 }
2118
2119 case DKIOCGMEDIAINFOEXT:
2120 {
2121 struct dk_minfo_ext dkmext;
2122
2123 bzero(&dkmext, sizeof (dkmext));
2124 dkmext.dki_lbsize = 1U << zv->zv_min_bs;
2125 dkmext.dki_pbsize = zv->zv_volblocksize;
2126 dkmext.dki_capacity = zv->zv_volsize >> zv->zv_min_bs;
2127 dkmext.dki_media_type = DK_UNKNOWN;
2128 mutex_exit(&zfsdev_state_lock);
2129 if (ddi_copyout(&dkmext, (void *)arg, sizeof (dkmext), flag))
2130 error = SET_ERROR(EFAULT);
2131 return (error);
2132 }
2133
2134 case DKIOCGETEFI:
2135 {
2136 uint64_t vs = zv->zv_volsize;
2137 uint8_t bs = zv->zv_min_bs;
2138
2139 mutex_exit(&zfsdev_state_lock);
2140 error = zvol_getefi((void *)arg, flag, vs, bs);
2141 return (error);
2142 }
2143
2144 case DKIOCFLUSHWRITECACHE:
2145 dkc = (struct dk_callback *)arg;
2146 mutex_exit(&zfsdev_state_lock);
2147 zil_commit(zv->zv_zilog, ZVOL_OBJ);
2148 if ((flag & FKIOCTL) && dkc != NULL && dkc->dkc_callback) {
2149 (*dkc->dkc_callback)(dkc->dkc_cookie, error);
2150 error = 0;
2151 }
2152 return (error);
2153
2154 case DKIOCGETWCE:
2155 {
2156 int wce = (zv->zv_flags & ZVOL_WCE) ? 1 : 0;
2157 if (ddi_copyout(&wce, (void *)arg, sizeof (int),
2158 flag))
2159 error = SET_ERROR(EFAULT);
2160 break;
2161 }
2162 case DKIOCSETWCE:
2163 {
2164 int wce;
2165 if (ddi_copyin((void *)arg, &wce, sizeof (int),
2166 flag)) {
2167 error = SET_ERROR(EFAULT);
2168 break;
2169 }
2170 if (wce) {
2171 zv->zv_flags |= ZVOL_WCE;
2172 mutex_exit(&zfsdev_state_lock);
2173 } else {
2174 zv->zv_flags &= ~ZVOL_WCE;
2175 mutex_exit(&zfsdev_state_lock);
2176 zil_commit(zv->zv_zilog, ZVOL_OBJ);
2177 }
2178 return (0);
2179 }
2180
2181 case DKIOCGGEOM:
2182 case DKIOCGVTOC:
2183 /*
2184 * commands using these (like prtvtoc) expect ENOTSUP
2185 * since we're emulating an EFI label
2186 */
2187 error = SET_ERROR(ENOTSUP);
2188 break;
2189
2190 case DKIOCDUMPINIT:
2191 rl = zfs_range_lock(&zv->zv_znode, 0, zv->zv_volsize,
2192 RL_WRITER);
2193 error = zvol_dumpify(zv);
2194 zfs_range_unlock(rl);
2195 break;
2196
2197 case DKIOCDUMPFINI:
2198 if (!(zv->zv_flags & ZVOL_DUMPIFIED))
2199 break;
2200 rl = zfs_range_lock(&zv->zv_znode, 0, zv->zv_volsize,
2201 RL_WRITER);
2202 error = zvol_dump_fini(zv);
2203 zfs_range_unlock(rl);
2204 break;
2205
2206 case DKIOCFREE:
2207 {
2208 dkioc_free_t df;
2209 dmu_tx_t *tx;
2210
2211 if (!zvol_unmap_enabled)
2212 break;
2213
2214 if (ddi_copyin((void *)arg, &df, sizeof (df), flag)) {
2215 error = SET_ERROR(EFAULT);
2216 break;
2217 }
2218
2219 /*
2220 * Apply Postel's Law to length-checking. If they overshoot,
2221 * just blank out until the end, if there's a need to blank
2222 * out anything.
2223 */
2224 if (df.df_start >= zv->zv_volsize)
2225 break; /* No need to do anything... */
2226
2227 mutex_exit(&zfsdev_state_lock);
2228
2229 rl = zfs_range_lock(&zv->zv_znode, df.df_start, df.df_length,
2230 RL_WRITER);
2231 tx = dmu_tx_create(zv->zv_objset);
2232 dmu_tx_mark_netfree(tx);
2233 error = dmu_tx_assign(tx, TXG_WAIT);
2234 if (error != 0) {
2235 dmu_tx_abort(tx);
2236 } else {
2237 zvol_log_truncate(zv, tx, df.df_start,
2238 df.df_length, B_TRUE);
2239 dmu_tx_commit(tx);
2240 error = dmu_free_long_range(zv->zv_objset, ZVOL_OBJ,
2241 df.df_start, df.df_length);
2242 }
2243
2244 zfs_range_unlock(rl);
2245
2246 if (error == 0) {
2247 /*
2248 * If the write-cache is disabled or 'sync' property
2249 * is set to 'always' then treat this as a synchronous
2250 * operation (i.e. commit to zil).
2251 */
2252 if (!(zv->zv_flags & ZVOL_WCE) ||
2253 (zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS))
2254 zil_commit(zv->zv_zilog, ZVOL_OBJ);
2255
2256 /*
2257 * If the caller really wants synchronous writes, and
2258 * can't wait for them, don't return until the write
2259 * is done.
2260 */
2261 if (df.df_flags & DF_WAIT_SYNC) {
2262 txg_wait_synced(
2263 dmu_objset_pool(zv->zv_objset), 0);
2264 }
2265 }
2266 return (error);
2267 }
2268
2269 default:
2270 error = SET_ERROR(ENOTTY);
2271 break;
2272
2273 }
2274 mutex_exit(&zfsdev_state_lock);
2275 return (error);
2276 }
2277 #endif /* illumos */
2278
2279 int
2280 zvol_busy(void)
2281 {
2282 return (zvol_minors != 0);
2283 }
2284
2285 void
2286 zvol_init(void)
2287 {
2288 VERIFY(ddi_soft_state_init(&zfsdev_state, sizeof (zfs_soft_state_t),
2289 1) == 0);
2290 #ifdef illumos
2291 mutex_init(&zfsdev_state_lock, NULL, MUTEX_DEFAULT, NULL);
2292 #else
2293 ZFS_LOG(1, "ZVOL Initialized.");
2294 #endif
2295 }
2296
2297 void
2298 zvol_fini(void)
2299 {
2300 #ifdef illumos
2301 mutex_destroy(&zfsdev_state_lock);
2302 #endif
2303 ddi_soft_state_fini(&zfsdev_state);
2304 ZFS_LOG(1, "ZVOL Deinitialized.");
2305 }
2306
2307 #ifdef illumos
2308 /*ARGSUSED*/
2309 static int
2310 zfs_mvdev_dump_feature_check(void *arg, dmu_tx_t *tx)
2311 {
2312 spa_t *spa = dmu_tx_pool(tx)->dp_spa;
2313
2314 if (spa_feature_is_active(spa, SPA_FEATURE_MULTI_VDEV_CRASH_DUMP))
2315 return (1);
2316 return (0);
2317 }
2318
2319 /*ARGSUSED*/
2320 static void
2321 zfs_mvdev_dump_activate_feature_sync(void *arg, dmu_tx_t *tx)
2322 {
2323 spa_t *spa = dmu_tx_pool(tx)->dp_spa;
2324
2325 spa_feature_incr(spa, SPA_FEATURE_MULTI_VDEV_CRASH_DUMP, tx);
2326 }
2327
2328 static int
2329 zvol_dump_init(zvol_state_t *zv, boolean_t resize)
2330 {
2331 dmu_tx_t *tx;
2332 int error;
2333 objset_t *os = zv->zv_objset;
2334 spa_t *spa = dmu_objset_spa(os);
2335 vdev_t *vd = spa->spa_root_vdev;
2336 nvlist_t *nv = NULL;
2337 uint64_t version = spa_version(spa);
2338 uint64_t checksum, compress, refresrv, vbs, dedup;
2339
2340 ASSERT(MUTEX_HELD(&zfsdev_state_lock));
2341 ASSERT(vd->vdev_ops == &vdev_root_ops);
2342
2343 error = dmu_free_long_range(zv->zv_objset, ZVOL_OBJ, 0,
2344 DMU_OBJECT_END);
2345 if (error != 0)
2346 return (error);
2347 /* wait for dmu_free_long_range to actually free the blocks */
2348 txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0);
2349
2350 /*
2351 * If the pool on which the dump device is being initialized has more
2352 * than one child vdev, check that the MULTI_VDEV_CRASH_DUMP feature is
2353 * enabled. If so, bump that feature's counter to indicate that the
2354 * feature is active. We also check the vdev type to handle the
2355 * following case:
2356 * # zpool create test raidz disk1 disk2 disk3
2357 * Now have spa_root_vdev->vdev_children == 1 (the raidz vdev),
2358 * the raidz vdev itself has 3 children.
2359 */
2360 if (vd->vdev_children > 1 || vd->vdev_ops == &vdev_raidz_ops) {
2361 if (!spa_feature_is_enabled(spa,
2362 SPA_FEATURE_MULTI_VDEV_CRASH_DUMP))
2363 return (SET_ERROR(ENOTSUP));
2364 (void) dsl_sync_task(spa_name(spa),
2365 zfs_mvdev_dump_feature_check,
2366 zfs_mvdev_dump_activate_feature_sync, NULL,
2367 2, ZFS_SPACE_CHECK_RESERVED);
2368 }
2369
2370 if (!resize) {
2371 error = dsl_prop_get_integer(zv->zv_name,
2372 zfs_prop_to_name(ZFS_PROP_COMPRESSION), &compress, NULL);
2373 if (error == 0) {
2374 error = dsl_prop_get_integer(zv->zv_name,
2375 zfs_prop_to_name(ZFS_PROP_CHECKSUM), &checksum,
2376 NULL);
2377 }
2378 if (error == 0) {
2379 error = dsl_prop_get_integer(zv->zv_name,
2380 zfs_prop_to_name(ZFS_PROP_REFRESERVATION),
2381 &refresrv, NULL);
2382 }
2383 if (error == 0) {
2384 error = dsl_prop_get_integer(zv->zv_name,
2385 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), &vbs,
2386 NULL);
2387 }
2388 if (version >= SPA_VERSION_DEDUP && error == 0) {
2389 error = dsl_prop_get_integer(zv->zv_name,
2390 zfs_prop_to_name(ZFS_PROP_DEDUP), &dedup, NULL);
2391 }
2392 }
2393 if (error != 0)
2394 return (error);
2395
2396 tx = dmu_tx_create(os);
2397 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL);
2398 dmu_tx_hold_bonus(tx, ZVOL_OBJ);
2399 error = dmu_tx_assign(tx, TXG_WAIT);
2400 if (error != 0) {
2401 dmu_tx_abort(tx);
2402 return (error);
2403 }
2404
2405 /*
2406 * If we are resizing the dump device then we only need to
2407 * update the refreservation to match the newly updated
2408 * zvolsize. Otherwise, we save off the original state of the
2409 * zvol so that we can restore them if the zvol is ever undumpified.
2410 */
2411 if (resize) {
2412 error = zap_update(os, ZVOL_ZAP_OBJ,
2413 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1,
2414 &zv->zv_volsize, tx);
2415 } else {
2416 error = zap_update(os, ZVOL_ZAP_OBJ,
2417 zfs_prop_to_name(ZFS_PROP_COMPRESSION), 8, 1,
2418 &compress, tx);
2419 if (error == 0) {
2420 error = zap_update(os, ZVOL_ZAP_OBJ,
2421 zfs_prop_to_name(ZFS_PROP_CHECKSUM), 8, 1,
2422 &checksum, tx);
2423 }
2424 if (error == 0) {
2425 error = zap_update(os, ZVOL_ZAP_OBJ,
2426 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1,
2427 &refresrv, tx);
2428 }
2429 if (error == 0) {
2430 error = zap_update(os, ZVOL_ZAP_OBJ,
2431 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), 8, 1,
2432 &vbs, tx);
2433 }
2434 if (error == 0) {
2435 error = dmu_object_set_blocksize(
2436 os, ZVOL_OBJ, SPA_OLD_MAXBLOCKSIZE, 0, tx);
2437 }
2438 if (version >= SPA_VERSION_DEDUP && error == 0) {
2439 error = zap_update(os, ZVOL_ZAP_OBJ,
2440 zfs_prop_to_name(ZFS_PROP_DEDUP), 8, 1,
2441 &dedup, tx);
2442 }
2443 if (error == 0)
2444 zv->zv_volblocksize = SPA_OLD_MAXBLOCKSIZE;
2445 }
2446 dmu_tx_commit(tx);
2447
2448 /*
2449 * We only need update the zvol's property if we are initializing
2450 * the dump area for the first time.
2451 */
2452 if (error == 0 && !resize) {
2453 /*
2454 * If MULTI_VDEV_CRASH_DUMP is active, use the NOPARITY checksum
2455 * function. Otherwise, use the old default -- OFF.
2456 */
2457 checksum = spa_feature_is_active(spa,
2458 SPA_FEATURE_MULTI_VDEV_CRASH_DUMP) ? ZIO_CHECKSUM_NOPARITY :
2459 ZIO_CHECKSUM_OFF;
2460
2461 VERIFY(nvlist_alloc(&nv, NV_UNIQUE_NAME, KM_SLEEP) == 0);
2462 VERIFY(nvlist_add_uint64(nv,
2463 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 0) == 0);
2464 VERIFY(nvlist_add_uint64(nv,
2465 zfs_prop_to_name(ZFS_PROP_COMPRESSION),
2466 ZIO_COMPRESS_OFF) == 0);
2467 VERIFY(nvlist_add_uint64(nv,
2468 zfs_prop_to_name(ZFS_PROP_CHECKSUM),
2469 checksum) == 0);
2470 if (version >= SPA_VERSION_DEDUP) {
2471 VERIFY(nvlist_add_uint64(nv,
2472 zfs_prop_to_name(ZFS_PROP_DEDUP),
2473 ZIO_CHECKSUM_OFF) == 0);
2474 }
2475
2476 error = zfs_set_prop_nvlist(zv->zv_name, ZPROP_SRC_LOCAL,
2477 nv, NULL);
2478 nvlist_free(nv);
2479 }
2480
2481 /* Allocate the space for the dump */
2482 if (error == 0)
2483 error = zvol_prealloc(zv);
2484 return (error);
2485 }
2486
2487 static int
2488 zvol_dumpify(zvol_state_t *zv)
2489 {
2490 int error = 0;
2491 uint64_t dumpsize = 0;
2492 dmu_tx_t *tx;
2493 objset_t *os = zv->zv_objset;
2494
2495 if (zv->zv_flags & ZVOL_RDONLY)
2496 return (SET_ERROR(EROFS));
2497
2498 if (zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE,
2499 8, 1, &dumpsize) != 0 || dumpsize != zv->zv_volsize) {
2500 boolean_t resize = (dumpsize > 0);
2501
2502 if ((error = zvol_dump_init(zv, resize)) != 0) {
2503 (void) zvol_dump_fini(zv);
2504 return (error);
2505 }
2506 }
2507
2508 /*
2509 * Build up our lba mapping.
2510 */
2511 error = zvol_get_lbas(zv);
2512 if (error) {
2513 (void) zvol_dump_fini(zv);
2514 return (error);
2515 }
2516
2517 tx = dmu_tx_create(os);
2518 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL);
2519 error = dmu_tx_assign(tx, TXG_WAIT);
2520 if (error) {
2521 dmu_tx_abort(tx);
2522 (void) zvol_dump_fini(zv);
2523 return (error);
2524 }
2525
2526 zv->zv_flags |= ZVOL_DUMPIFIED;
2527 error = zap_update(os, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE, 8, 1,
2528 &zv->zv_volsize, tx);
2529 dmu_tx_commit(tx);
2530
2531 if (error) {
2532 (void) zvol_dump_fini(zv);
2533 return (error);
2534 }
2535
2536 txg_wait_synced(dmu_objset_pool(os), 0);
2537 return (0);
2538 }
2539
2540 static int
2541 zvol_dump_fini(zvol_state_t *zv)
2542 {
2543 dmu_tx_t *tx;
2544 objset_t *os = zv->zv_objset;
2545 nvlist_t *nv;
2546 int error = 0;
2547 uint64_t checksum, compress, refresrv, vbs, dedup;
2548 uint64_t version = spa_version(dmu_objset_spa(zv->zv_objset));
2549
2550 /*
2551 * Attempt to restore the zvol back to its pre-dumpified state.
2552 * This is a best-effort attempt as it's possible that not all
2553 * of these properties were initialized during the dumpify process
2554 * (i.e. error during zvol_dump_init).
2555 */
2556
2557 tx = dmu_tx_create(os);
2558 dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL);
2559 error = dmu_tx_assign(tx, TXG_WAIT);
2560 if (error) {
2561 dmu_tx_abort(tx);
2562 return (error);
2563 }
2564 (void) zap_remove(os, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE, tx);
2565 dmu_tx_commit(tx);
2566
2567 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ,
2568 zfs_prop_to_name(ZFS_PROP_CHECKSUM), 8, 1, &checksum);
2569 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ,
2570 zfs_prop_to_name(ZFS_PROP_COMPRESSION), 8, 1, &compress);
2571 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ,
2572 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1, &refresrv);
2573 (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ,
2574 zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), 8, 1, &vbs);
2575
2576 VERIFY(nvlist_alloc(&nv, NV_UNIQUE_NAME, KM_SLEEP) == 0);
2577 (void) nvlist_add_uint64(nv,
2578 zfs_prop_to_name(ZFS_PROP_CHECKSUM), checksum);
2579 (void) nvlist_add_uint64(nv,
2580 zfs_prop_to_name(ZFS_PROP_COMPRESSION), compress);
2581 (void) nvlist_add_uint64(nv,
2582 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), refresrv);
2583 if (version >= SPA_VERSION_DEDUP &&
2584 zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ,
2585 zfs_prop_to_name(ZFS_PROP_DEDUP), 8, 1, &dedup) == 0) {
2586 (void) nvlist_add_uint64(nv,
2587 zfs_prop_to_name(ZFS_PROP_DEDUP), dedup);
2588 }
2589 (void) zfs_set_prop_nvlist(zv->zv_name, ZPROP_SRC_LOCAL,
2590 nv, NULL);
2591 nvlist_free(nv);
2592
2593 zvol_free_extents(zv);
2594 zv->zv_flags &= ~ZVOL_DUMPIFIED;
2595 (void) dmu_free_long_range(os, ZVOL_OBJ, 0, DMU_OBJECT_END);
2596 /* wait for dmu_free_long_range to actually free the blocks */
2597 txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0);
2598 tx = dmu_tx_create(os);
2599 dmu_tx_hold_bonus(tx, ZVOL_OBJ);
2600 error = dmu_tx_assign(tx, TXG_WAIT);
2601 if (error) {
2602 dmu_tx_abort(tx);
2603 return (error);
2604 }
2605 if (dmu_object_set_blocksize(os, ZVOL_OBJ, vbs, 0, tx) == 0)
2606 zv->zv_volblocksize = vbs;
2607 dmu_tx_commit(tx);
2608
2609 return (0);
2610 }
2611 #else /* !illumos */
2612
2613 static void
2614 zvol_geom_run(zvol_state_t *zv)
2615 {
2616 struct g_provider *pp;
2617
2618 pp = zv->zv_provider;
2619 g_error_provider(pp, 0);
2620
2621 kproc_kthread_add(zvol_geom_worker, zv, &zfsproc, NULL, 0, 0,
2622 "zfskern", "zvol %s", pp->name + sizeof(ZVOL_DRIVER));
2623 }
2624
2625 static void
2626 zvol_geom_destroy(zvol_state_t *zv)
2627 {
2628 struct g_provider *pp;
2629
2630 g_topology_assert();
2631
2632 mtx_lock(&zv->zv_queue_mtx);
2633 zv->zv_state = 1;
2634 wakeup_one(&zv->zv_queue);
2635 while (zv->zv_state != 2)
2636 msleep(&zv->zv_state, &zv->zv_queue_mtx, 0, "zvol:w", 0);
2637 mtx_destroy(&zv->zv_queue_mtx);
2638
2639 pp = zv->zv_provider;
2640 zv->zv_provider = NULL;
2641 pp->private = NULL;
2642 g_wither_geom(pp->geom, ENXIO);
2643 }
2644
2645 static int
2646 zvol_geom_access(struct g_provider *pp, int acr, int acw, int ace)
2647 {
2648 int count, error, flags;
2649
2650 g_topology_assert();
2651
2652 /*
2653 * To make it easier we expect either open or close, but not both
2654 * at the same time.
2655 */
2656 KASSERT((acr >= 0 && acw >= 0 && ace >= 0) ||
2657 (acr <= 0 && acw <= 0 && ace <= 0),
2658 ("Unsupported access request to %s (acr=%d, acw=%d, ace=%d).",
2659 pp->name, acr, acw, ace));
2660
2661 if (pp->private == NULL) {
2662 if (acr <= 0 && acw <= 0 && ace <= 0)
2663 return (0);
2664 return (pp->error);
2665 }
2666
2667 /*
2668 * We don't pass FEXCL flag to zvol_open()/zvol_close() if ace != 0,
2669 * because GEOM already handles that and handles it a bit differently.
2670 * GEOM allows for multiple read/exclusive consumers and ZFS allows
2671 * only one exclusive consumer, no matter if it is reader or writer.
2672 * I like better the way GEOM works so I'll leave it for GEOM to
2673 * decide what to do.
2674 */
2675
2676 count = acr + acw + ace;
2677 if (count == 0)
2678 return (0);
2679
2680 flags = 0;
2681 if (acr != 0 || ace != 0)
2682 flags |= FREAD;
2683 if (acw != 0)
2684 flags |= FWRITE;
2685
2686 g_topology_unlock();
2687 if (count > 0)
2688 error = zvol_open(pp, flags, count);
2689 else
2690 error = zvol_close(pp, flags, -count);
2691 g_topology_lock();
2692 return (error);
2693 }
2694
2695 static void
2696 zvol_geom_start(struct bio *bp)
2697 {
2698 zvol_state_t *zv;
2699 boolean_t first;
2700
2701 zv = bp->bio_to->private;
2702 ASSERT(zv != NULL);
2703 switch (bp->bio_cmd) {
2704 case BIO_FLUSH:
2705 if (!THREAD_CAN_SLEEP())
2706 goto enqueue;
2707 zil_commit(zv->zv_zilog, ZVOL_OBJ);
2708 g_io_deliver(bp, 0);
2709 break;
2710 case BIO_READ:
2711 case BIO_WRITE:
2712 case BIO_DELETE:
2713 if (!THREAD_CAN_SLEEP())
2714 goto enqueue;
2715 zvol_strategy(bp);
2716 break;
2717 case BIO_GETATTR: {
2718 spa_t *spa = dmu_objset_spa(zv->zv_objset);
2719 uint64_t refd, avail, usedobjs, availobjs, val;
2720
2721 if (g_handleattr_int(bp, "GEOM::candelete", 1))
2722 return;
2723 if (strcmp(bp->bio_attribute, "blocksavail") == 0) {
2724 dmu_objset_space(zv->zv_objset, &refd, &avail,
2725 &usedobjs, &availobjs);
2726 if (g_handleattr_off_t(bp, "blocksavail",
2727 avail / DEV_BSIZE))
2728 return;
2729 } else if (strcmp(bp->bio_attribute, "blocksused") == 0) {
2730 dmu_objset_space(zv->zv_objset, &refd, &avail,
2731 &usedobjs, &availobjs);
2732 if (g_handleattr_off_t(bp, "blocksused",
2733 refd / DEV_BSIZE))
2734 return;
2735 } else if (strcmp(bp->bio_attribute, "poolblocksavail") == 0) {
2736 avail = metaslab_class_get_space(spa_normal_class(spa));
2737 avail -= metaslab_class_get_alloc(spa_normal_class(spa));
2738 if (g_handleattr_off_t(bp, "poolblocksavail",
2739 avail / DEV_BSIZE))
2740 return;
2741 } else if (strcmp(bp->bio_attribute, "poolblocksused") == 0) {
2742 refd = metaslab_class_get_alloc(spa_normal_class(spa));
2743 if (g_handleattr_off_t(bp, "poolblocksused",
2744 refd / DEV_BSIZE))
2745 return;
2746 }
2747 /* FALLTHROUGH */
2748 }
2749 default:
2750 g_io_deliver(bp, EOPNOTSUPP);
2751 break;
2752 }
2753 return;
2754
2755 enqueue:
2756 mtx_lock(&zv->zv_queue_mtx);
2757 first = (bioq_first(&zv->zv_queue) == NULL);
2758 bioq_insert_tail(&zv->zv_queue, bp);
2759 mtx_unlock(&zv->zv_queue_mtx);
2760 if (first)
2761 wakeup_one(&zv->zv_queue);
2762 }
2763
2764 static void
2765 zvol_geom_worker(void *arg)
2766 {
2767 zvol_state_t *zv;
2768 struct bio *bp;
2769
2770 thread_lock(curthread);
2771 sched_prio(curthread, PRIBIO);
2772 thread_unlock(curthread);
2773
2774 zv = arg;
2775 for (;;) {
2776 mtx_lock(&zv->zv_queue_mtx);
2777 bp = bioq_takefirst(&zv->zv_queue);
2778 if (bp == NULL) {
2779 if (zv->zv_state == 1) {
2780 zv->zv_state = 2;
2781 wakeup(&zv->zv_state);
2782 mtx_unlock(&zv->zv_queue_mtx);
2783 kthread_exit();
2784 }
2785 msleep(&zv->zv_queue, &zv->zv_queue_mtx, PRIBIO | PDROP,
2786 "zvol:io", 0);
2787 continue;
2788 }
2789 mtx_unlock(&zv->zv_queue_mtx);
2790 switch (bp->bio_cmd) {
2791 case BIO_FLUSH:
2792 zil_commit(zv->zv_zilog, ZVOL_OBJ);
2793 g_io_deliver(bp, 0);
2794 break;
2795 case BIO_READ:
2796 case BIO_WRITE:
2797 case BIO_DELETE:
2798 zvol_strategy(bp);
2799 break;
2800 default:
2801 g_io_deliver(bp, EOPNOTSUPP);
2802 break;
2803 }
2804 }
2805 }
2806
2807 extern boolean_t dataset_name_hidden(const char *name);
2808
2809 static int
2810 zvol_create_snapshots(objset_t *os, const char *name)
2811 {
2812 uint64_t cookie, obj;
2813 char *sname;
2814 int error, len;
2815
2816 cookie = obj = 0;
2817 sname = kmem_alloc(MAXPATHLEN, KM_SLEEP);
2818
2819 #if 0
2820 (void) dmu_objset_find(name, dmu_objset_prefetch, NULL,
2821 DS_FIND_SNAPSHOTS);
2822 #endif
2823
2824 for (;;) {
2825 len = snprintf(sname, MAXPATHLEN, "%s@", name);
2826 if (len >= MAXPATHLEN) {
2827 dmu_objset_rele(os, FTAG);
2828 error = ENAMETOOLONG;
2829 break;
2830 }
2831
2832 dsl_pool_config_enter(dmu_objset_pool(os), FTAG);
2833 error = dmu_snapshot_list_next(os, MAXPATHLEN - len,
2834 sname + len, &obj, &cookie, NULL);
2835 dsl_pool_config_exit(dmu_objset_pool(os), FTAG);
2836 if (error != 0) {
2837 if (error == ENOENT)
2838 error = 0;
2839 break;
2840 }
2841
2842 if ((error = zvol_create_minor(sname)) != 0) {
2843 printf("ZFS WARNING: Unable to create ZVOL %s (error=%d).\n",
2844 sname, error);
2845 break;
2846 }
2847 }
2848
2849 kmem_free(sname, MAXPATHLEN);
2850 return (error);
2851 }
2852
2853 int
2854 zvol_create_minors(const char *name)
2855 {
2856 uint64_t cookie;
2857 objset_t *os;
2858 char *osname, *p;
2859 int error, len;
2860
2861 if (dataset_name_hidden(name))
2862 return (0);
2863
2864 if ((error = dmu_objset_hold(name, FTAG, &os)) != 0) {
2865 printf("ZFS WARNING: Unable to put hold on %s (error=%d).\n",
2866 name, error);
2867 return (error);
2868 }
2869 if (dmu_objset_type(os) == DMU_OST_ZVOL) {
2870 dsl_dataset_long_hold(os->os_dsl_dataset, FTAG);
2871 dsl_pool_rele(dmu_objset_pool(os), FTAG);
2872 error = zvol_create_minor(name);
2873 if (error == 0 || error == EEXIST) {
2874 error = zvol_create_snapshots(os, name);
2875 } else {
2876 printf("ZFS WARNING: Unable to create ZVOL %s (error=%d).\n",
2877 name, error);
2878 }
2879 dsl_dataset_long_rele(os->os_dsl_dataset, FTAG);
2880 dsl_dataset_rele(os->os_dsl_dataset, FTAG);
2881 return (error);
2882 }
2883 if (dmu_objset_type(os) != DMU_OST_ZFS) {
2884 dmu_objset_rele(os, FTAG);
2885 return (0);
2886 }
2887
2888 osname = kmem_alloc(MAXPATHLEN, KM_SLEEP);
2889 if (snprintf(osname, MAXPATHLEN, "%s/", name) >= MAXPATHLEN) {
2890 dmu_objset_rele(os, FTAG);
2891 kmem_free(osname, MAXPATHLEN);
2892 return (ENOENT);
2893 }
2894 p = osname + strlen(osname);
2895 len = MAXPATHLEN - (p - osname);
2896
2897 #if 0
2898 /* Prefetch the datasets. */
2899 cookie = 0;
2900 while (dmu_dir_list_next(os, len, p, NULL, &cookie) == 0) {
2901 if (!dataset_name_hidden(osname))
2902 (void) dmu_objset_prefetch(osname, NULL);
2903 }
2904 #endif
2905
2906 cookie = 0;
2907 while (dmu_dir_list_next(os, MAXPATHLEN - (p - osname), p, NULL,
2908 &cookie) == 0) {
2909 dmu_objset_rele(os, FTAG);
2910 (void)zvol_create_minors(osname);
2911 if ((error = dmu_objset_hold(name, FTAG, &os)) != 0) {
2912 printf("ZFS WARNING: Unable to put hold on %s (error=%d).\n",
2913 name, error);
2914 return (error);
2915 }
2916 }
2917
2918 dmu_objset_rele(os, FTAG);
2919 kmem_free(osname, MAXPATHLEN);
2920 return (0);
2921 }
2922
2923 static void
2924 zvol_rename_minor(zvol_state_t *zv, const char *newname)
2925 {
2926 struct g_geom *gp;
2927 struct g_provider *pp;
2928 struct cdev *dev;
2929
2930 ASSERT(MUTEX_HELD(&zfsdev_state_lock));
2931
2932 if (zv->zv_volmode == ZFS_VOLMODE_GEOM) {
2933 g_topology_lock();
2934 pp = zv->zv_provider;
2935 ASSERT(pp != NULL);
2936 gp = pp->geom;
2937 ASSERT(gp != NULL);
2938
2939 zv->zv_provider = NULL;
2940 g_wither_provider(pp, ENXIO);
2941
2942 pp = g_new_providerf(gp, "%s/%s", ZVOL_DRIVER, newname);
2943 pp->flags |= G_PF_DIRECT_RECEIVE | G_PF_DIRECT_SEND;
2944 pp->sectorsize = DEV_BSIZE;
2945 pp->mediasize = zv->zv_volsize;
2946 pp->private = zv;
2947 zv->zv_provider = pp;
2948 g_error_provider(pp, 0);
2949 g_topology_unlock();
2950 } else if (zv->zv_volmode == ZFS_VOLMODE_DEV) {
2951 dev = zv->zv_dev;
2952 ASSERT(dev != NULL);
2953 zv->zv_dev = NULL;
2954 destroy_dev(dev);
2955
2956 if (make_dev_p(MAKEDEV_CHECKNAME | MAKEDEV_WAITOK,
2957 &dev, &zvol_cdevsw, NULL, UID_ROOT, GID_OPERATOR,
2958 0640, "%s/%s", ZVOL_DRIVER, newname) == 0) {
2959 zv->zv_dev = dev;
2960 dev->si_iosize_max = MAXPHYS;
2961 dev->si_drv2 = zv;
2962 }
2963 }
2964 strlcpy(zv->zv_name, newname, sizeof(zv->zv_name));
2965 }
2966
2967 void
2968 zvol_rename_minors(const char *oldname, const char *newname)
2969 {
2970 char name[MAXPATHLEN];
2971 struct g_provider *pp;
2972 struct g_geom *gp;
2973 size_t oldnamelen, newnamelen;
2974 zvol_state_t *zv;
2975 char *namebuf;
2976 boolean_t locked = B_FALSE;
2977
2978 oldnamelen = strlen(oldname);
2979 newnamelen = strlen(newname);
2980
2981 DROP_GIANT();
2982 /* See comment in zvol_open(). */
2983 if (!MUTEX_HELD(&zfsdev_state_lock)) {
2984 mutex_enter(&zfsdev_state_lock);
2985 locked = B_TRUE;
2986 }
2987
2988 LIST_FOREACH(zv, &all_zvols, zv_links) {
2989 if (strcmp(zv->zv_name, oldname) == 0) {
2990 zvol_rename_minor(zv, newname);
2991 } else if (strncmp(zv->zv_name, oldname, oldnamelen) == 0 &&
2992 (zv->zv_name[oldnamelen] == '/' ||
2993 zv->zv_name[oldnamelen] == '@')) {
2994 snprintf(name, sizeof(name), "%s%c%s", newname,
2995 zv->zv_name[oldnamelen],
2996 zv->zv_name + oldnamelen + 1);
2997 zvol_rename_minor(zv, name);
2998 }
2999 }
3000
3001 if (locked)
3002 mutex_exit(&zfsdev_state_lock);
3003 PICKUP_GIANT();
3004 }
3005
3006 static int
3007 zvol_d_open(struct cdev *dev, int flags, int fmt, struct thread *td)
3008 {
3009 zvol_state_t *zv;
3010 int err = 0;
3011
3012 mutex_enter(&zfsdev_state_lock);
3013 zv = dev->si_drv2;
3014 if (zv == NULL) {
3015 mutex_exit(&zfsdev_state_lock);
3016 return(ENXIO); /* zvol_create_minor() not done yet */
3017 }
3018
3019 if (zv->zv_total_opens == 0)
3020 err = zvol_first_open(zv);
3021 if (err) {
3022 mutex_exit(&zfsdev_state_lock);
3023 return (err);
3024 }
3025 if ((flags & FWRITE) && (zv->zv_flags & ZVOL_RDONLY)) {
3026 err = SET_ERROR(EROFS);
3027 goto out;
3028 }
3029 if (zv->zv_flags & ZVOL_EXCL) {
3030 err = SET_ERROR(EBUSY);
3031 goto out;
3032 }
3033 #ifdef FEXCL
3034 if (flags & FEXCL) {
3035 if (zv->zv_total_opens != 0) {
3036 err = SET_ERROR(EBUSY);
3037 goto out;
3038 }
3039 zv->zv_flags |= ZVOL_EXCL;
3040 }
3041 #endif
3042
3043 zv->zv_total_opens++;
3044 mutex_exit(&zfsdev_state_lock);
3045 return (err);
3046 out:
3047 if (zv->zv_total_opens == 0)
3048 zvol_last_close(zv);
3049 mutex_exit(&zfsdev_state_lock);
3050 return (err);
3051 }
3052
3053 static int
3054 zvol_d_close(struct cdev *dev, int flags, int fmt, struct thread *td)
3055 {
3056 zvol_state_t *zv;
3057 int err = 0;
3058
3059 mutex_enter(&zfsdev_state_lock);
3060 zv = dev->si_drv2;
3061 if (zv == NULL) {
3062 mutex_exit(&zfsdev_state_lock);
3063 return(ENXIO);
3064 }
3065
3066 if (zv->zv_flags & ZVOL_EXCL) {
3067 ASSERT(zv->zv_total_opens == 1);
3068 zv->zv_flags &= ~ZVOL_EXCL;
3069 }
3070
3071 /*
3072 * If the open count is zero, this is a spurious close.
3073 * That indicates a bug in the kernel / DDI framework.
3074 */
3075 ASSERT(zv->zv_total_opens != 0);
3076
3077 /*
3078 * You may get multiple opens, but only one close.
3079 */
3080 zv->zv_total_opens--;
3081
3082 if (zv->zv_total_opens == 0)
3083 zvol_last_close(zv);
3084
3085 mutex_exit(&zfsdev_state_lock);
3086 return (0);
3087 }
3088
3089 static int
3090 zvol_d_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag, struct thread *td)
3091 {
3092 zvol_state_t *zv;
3093 rl_t *rl;
3094 off_t offset, length, chunk;
3095 int i, error;
3096 u_int u;
3097
3098 zv = dev->si_drv2;
3099
3100 error = 0;
3101 KASSERT(zv->zv_total_opens > 0,
3102 ("Device with zero access count in zvol_d_ioctl"));
3103
3104 i = IOCPARM_LEN(cmd);
3105 switch (cmd) {
3106 case DIOCGSECTORSIZE:
3107 *(u_int *)data = DEV_BSIZE;
3108 break;
3109 case DIOCGMEDIASIZE:
3110 *(off_t *)data = zv->zv_volsize;
3111 break;
3112 case DIOCGFLUSH:
3113 zil_commit(zv->zv_zilog, ZVOL_OBJ);
3114 break;
3115 case DIOCGDELETE:
3116 if (!zvol_unmap_enabled)
3117 break;
3118
3119 offset = ((off_t *)data)[0];
3120 length = ((off_t *)data)[1];
3121 if ((offset % DEV_BSIZE) != 0 || (length % DEV_BSIZE) != 0 ||
3122 offset < 0 || offset >= zv->zv_volsize ||
3123 length <= 0) {
3124 printf("%s: offset=%jd length=%jd\n", __func__, offset,
3125 length);
3126 error = EINVAL;
3127 break;
3128 }
3129
3130 rl = zfs_range_lock(&zv->zv_znode, offset, length, RL_WRITER);
3131 dmu_tx_t *tx = dmu_tx_create(zv->zv_objset);
3132 error = dmu_tx_assign(tx, TXG_WAIT);
3133 if (error != 0) {
3134 dmu_tx_abort(tx);
3135 } else {
3136 zvol_log_truncate(zv, tx, offset, length, B_TRUE);
3137 dmu_tx_commit(tx);
3138 error = dmu_free_long_range(zv->zv_objset, ZVOL_OBJ,
3139 offset, length);
3140 }
3141 zfs_range_unlock(rl);
3142 if (zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS)
3143 zil_commit(zv->zv_zilog, ZVOL_OBJ);
3144 break;
3145 case DIOCGSTRIPESIZE:
3146 *(off_t *)data = zv->zv_volblocksize;
3147 break;
3148 case DIOCGSTRIPEOFFSET:
3149 *(off_t *)data = 0;
3150 break;
3151 case DIOCGATTR: {
3152 spa_t *spa = dmu_objset_spa(zv->zv_objset);
3153 struct diocgattr_arg *arg = (struct diocgattr_arg *)data;
3154 uint64_t refd, avail, usedobjs, availobjs;
3155
3156 if (strcmp(arg->name, "GEOM::candelete") == 0)
3157 arg->value.i = 1;
3158 else if (strcmp(arg->name, "blocksavail") == 0) {
3159 dmu_objset_space(zv->zv_objset, &refd, &avail,
3160 &usedobjs, &availobjs);
3161 arg->value.off = avail / DEV_BSIZE;
3162 } else if (strcmp(arg->name, "blocksused") == 0) {
3163 dmu_objset_space(zv->zv_objset, &refd, &avail,
3164 &usedobjs, &availobjs);
3165 arg->value.off = refd / DEV_BSIZE;
3166 } else if (strcmp(arg->name, "poolblocksavail") == 0) {
3167 avail = metaslab_class_get_space(spa_normal_class(spa));
3168 avail -= metaslab_class_get_alloc(spa_normal_class(spa));
3169 arg->value.off = avail / DEV_BSIZE;
3170 } else if (strcmp(arg->name, "poolblocksused") == 0) {
3171 refd = metaslab_class_get_alloc(spa_normal_class(spa));
3172 arg->value.off = refd / DEV_BSIZE;
3173 } else
3174 error = ENOIOCTL;
3175 break;
3176 }
3177 case FIOSEEKHOLE:
3178 case FIOSEEKDATA: {
3179 off_t *off = (off_t *)data;
3180 uint64_t noff;
3181 boolean_t hole;
3182
3183 hole = (cmd == FIOSEEKHOLE);
3184 noff = *off;
3185 error = dmu_offset_next(zv->zv_objset, ZVOL_OBJ, hole, &noff);
3186 *off = noff;
3187 break;
3188 }
3189 default:
3190 error = ENOIOCTL;
3191 }
3192
3193 return (error);
3194 }
3195 #endif /* illumos */
3196