]>
Commit | Line | Data |
---|---|---|
60101509 BB |
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) 2008-2010 Lawrence Livermore National Security, LLC. | |
23 | * Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER). | |
24 | * Rewritten for Linux by Brian Behlendorf <behlendorf1@llnl.gov>. | |
25 | * LLNL-CODE-403049. | |
26 | * | |
27 | * ZFS volume emulation driver. | |
28 | * | |
29 | * Makes a DMU object look like a volume of arbitrary size, up to 2^64 bytes. | |
30 | * Volumes are accessed through the symbolic links named: | |
31 | * | |
32 | * /dev/<pool_name>/<dataset_name> | |
33 | * | |
34 | * Volumes are persistent through reboot and module load. No user command | |
35 | * needs to be run before opening and using a device. | |
460a0213 DM |
36 | * |
37 | * Copyright 2014 Nexenta Systems, Inc. All rights reserved. | |
5428dc51 | 38 | * Copyright (c) 2016 Actifio, Inc. All rights reserved. |
60101509 BB |
39 | */ |
40 | ||
5559ba09 BP |
41 | /* |
42 | * Note on locking of zvol state structures. | |
43 | * | |
44 | * These structures are used to maintain internal state used to emulate block | |
45 | * devices on top of zvols. In particular, management of device minor number | |
46 | * operations - create, remove, rename, and set_snapdev - involves access to | |
47 | * these structures. The zvol_state_lock is primarily used to protect the | |
48 | * zvol_state_list. The zv->zv_state_lock is used to protect the contents | |
49 | * of the zvol_state_t structures, as well as to make sure that when the | |
50 | * time comes to remove the structure from the list, it is not in use, and | |
51 | * therefore, it can be taken off zvol_state_list and freed. | |
52 | * | |
53 | * The minor operations are issued to the spa->spa_zvol_taskq quues, that are | |
54 | * single-threaded (to preserve order of minor operations), and are executed | |
55 | * through the zvol_task_cb that dispatches the specific operations. Therefore, | |
56 | * these operations are serialized per pool. Consequently, we can be certain | |
57 | * that for a given zvol, there is only one operation at a time in progress. | |
58 | * That is why one can be sure that first, zvol_state_t for a given zvol is | |
59 | * allocated and placed on zvol_state_list, and then other minor operations | |
60 | * for this zvol are going to proceed in the order of issue. | |
61 | * | |
62 | * It is also worth keeping in mind that once add_disk() is called, the zvol is | |
63 | * announced to the world, and zvol_open()/zvol_release() can be called at any | |
64 | * time. Incidentally, add_disk() itself calls zvol_open()->zvol_first_open() | |
65 | * and zvol_release()->zvol_last_close() directly as well. | |
66 | */ | |
67 | ||
03c6040b | 68 | #include <sys/dbuf.h> |
60101509 BB |
69 | #include <sys/dmu_traverse.h> |
70 | #include <sys/dsl_dataset.h> | |
71 | #include <sys/dsl_prop.h> | |
a0bd735a | 72 | #include <sys/dsl_dir.h> |
60101509 | 73 | #include <sys/zap.h> |
4cb7b9c5 | 74 | #include <sys/zfeature.h> |
60101509 | 75 | #include <sys/zil_impl.h> |
460a0213 | 76 | #include <sys/dmu_tx.h> |
60101509 BB |
77 | #include <sys/zio.h> |
78 | #include <sys/zfs_rlock.h> | |
79 | #include <sys/zfs_znode.h> | |
a0bd735a | 80 | #include <sys/spa_impl.h> |
60101509 | 81 | #include <sys/zvol.h> |
61e90960 | 82 | #include <linux/blkdev_compat.h> |
60101509 | 83 | |
74497b7a | 84 | unsigned int zvol_inhibit_dev = 0; |
60101509 | 85 | unsigned int zvol_major = ZVOL_MAJOR; |
692e55b8 | 86 | unsigned int zvol_threads = 32; |
8fa5250f | 87 | unsigned int zvol_request_sync = 0; |
9965059a | 88 | unsigned int zvol_prefetch_bytes = (128 * 1024); |
7c0e5708 | 89 | unsigned long zvol_max_discard_blocks = 16384; |
60101509 | 90 | |
692e55b8 | 91 | static taskq_t *zvol_taskq; |
60101509 BB |
92 | static kmutex_t zvol_state_lock; |
93 | static list_t zvol_state_list; | |
60101509 | 94 | |
d45e010d CC |
95 | #define ZVOL_HT_SIZE 1024 |
96 | static struct hlist_head *zvol_htable; | |
97 | #define ZVOL_HT_HEAD(hash) (&zvol_htable[(hash) & (ZVOL_HT_SIZE-1)]) | |
4a5d7f82 MA |
98 | |
99 | static struct ida zvol_ida; | |
d45e010d | 100 | |
60101509 BB |
101 | /* |
102 | * The in-core state of each volume. | |
103 | */ | |
040dab99 | 104 | struct zvol_state { |
4c0d8e50 | 105 | char zv_name[MAXNAMELEN]; /* name */ |
ce37ebd2 BB |
106 | uint64_t zv_volsize; /* advertised space */ |
107 | uint64_t zv_volblocksize; /* volume block size */ | |
60101509 BB |
108 | objset_t *zv_objset; /* objset handle */ |
109 | uint32_t zv_flags; /* ZVOL_* flags */ | |
110 | uint32_t zv_open_count; /* open counts */ | |
111 | uint32_t zv_changed; /* disk changed */ | |
112 | zilog_t *zv_zilog; /* ZIL handle */ | |
d88895a0 | 113 | zfs_rlock_t zv_range_lock; /* range lock */ |
60101509 BB |
114 | dmu_buf_t *zv_dbuf; /* bonus handle */ |
115 | dev_t zv_dev; /* device id */ | |
116 | struct gendisk *zv_disk; /* generic disk */ | |
117 | struct request_queue *zv_queue; /* request queue */ | |
60101509 | 118 | list_node_t zv_next; /* next zvol_state_t linkage */ |
d45e010d CC |
119 | uint64_t zv_hash; /* name hash */ |
120 | struct hlist_node zv_hlink; /* hash link */ | |
5559ba09 | 121 | kmutex_t zv_state_lock; /* protects zvol_state_t */ |
040dab99 CC |
122 | atomic_t zv_suspend_ref; /* refcount for suspend */ |
123 | krwlock_t zv_suspend_lock; /* suspend lock */ | |
124 | }; | |
60101509 | 125 | |
a0bd735a BP |
126 | typedef enum { |
127 | ZVOL_ASYNC_CREATE_MINORS, | |
128 | ZVOL_ASYNC_REMOVE_MINORS, | |
129 | ZVOL_ASYNC_RENAME_MINORS, | |
130 | ZVOL_ASYNC_SET_SNAPDEV, | |
131 | ZVOL_ASYNC_MAX | |
132 | } zvol_async_op_t; | |
133 | ||
134 | typedef struct { | |
135 | zvol_async_op_t op; | |
136 | char pool[MAXNAMELEN]; | |
137 | char name1[MAXNAMELEN]; | |
138 | char name2[MAXNAMELEN]; | |
139 | zprop_source_t source; | |
140 | uint64_t snapdev; | |
141 | } zvol_task_t; | |
142 | ||
60101509 BB |
143 | #define ZVOL_RDONLY 0x1 |
144 | ||
d45e010d CC |
145 | static uint64_t |
146 | zvol_name_hash(const char *name) | |
60101509 | 147 | { |
d45e010d CC |
148 | int i; |
149 | uint64_t crc = -1ULL; | |
150 | uint8_t *p = (uint8_t *)name; | |
151 | ASSERT(zfs_crc64_table[128] == ZFS_CRC64_POLY); | |
152 | for (i = 0; i < MAXNAMELEN - 1 && *p; i++, p++) { | |
153 | crc = (crc >> 8) ^ zfs_crc64_table[(crc ^ (*p)) & 0xFF]; | |
60101509 | 154 | } |
d45e010d | 155 | return (crc); |
60101509 BB |
156 | } |
157 | ||
158 | /* | |
159 | * Find a zvol_state_t given the full major+minor dev_t. | |
160 | */ | |
161 | static zvol_state_t * | |
162 | zvol_find_by_dev(dev_t dev) | |
163 | { | |
164 | zvol_state_t *zv; | |
165 | ||
166 | ASSERT(MUTEX_HELD(&zvol_state_lock)); | |
167 | for (zv = list_head(&zvol_state_list); zv != NULL; | |
ce37ebd2 | 168 | zv = list_next(&zvol_state_list, zv)) { |
60101509 | 169 | if (zv->zv_dev == dev) |
ce37ebd2 | 170 | return (zv); |
60101509 BB |
171 | } |
172 | ||
ce37ebd2 | 173 | return (NULL); |
60101509 BB |
174 | } |
175 | ||
176 | /* | |
d45e010d | 177 | * Find a zvol_state_t given the name and hash generated by zvol_name_hash. |
60101509 BB |
178 | */ |
179 | static zvol_state_t * | |
d45e010d | 180 | zvol_find_by_name_hash(const char *name, uint64_t hash) |
60101509 BB |
181 | { |
182 | zvol_state_t *zv; | |
d45e010d | 183 | struct hlist_node *p; |
60101509 BB |
184 | |
185 | ASSERT(MUTEX_HELD(&zvol_state_lock)); | |
d45e010d CC |
186 | hlist_for_each(p, ZVOL_HT_HEAD(hash)) { |
187 | zv = hlist_entry(p, zvol_state_t, zv_hlink); | |
188 | if (zv->zv_hash == hash && | |
189 | strncmp(zv->zv_name, name, MAXNAMELEN) == 0) | |
ce37ebd2 | 190 | return (zv); |
60101509 | 191 | } |
ce37ebd2 | 192 | return (NULL); |
60101509 BB |
193 | } |
194 | ||
d45e010d CC |
195 | /* |
196 | * Find a zvol_state_t given the name provided at zvol_alloc() time. | |
197 | */ | |
198 | static zvol_state_t * | |
199 | zvol_find_by_name(const char *name) | |
200 | { | |
201 | return (zvol_find_by_name_hash(name, zvol_name_hash(name))); | |
202 | } | |
203 | ||
6c285672 JL |
204 | |
205 | /* | |
206 | * Given a path, return TRUE if path is a ZVOL. | |
207 | */ | |
208 | boolean_t | |
209 | zvol_is_zvol(const char *device) | |
210 | { | |
211 | struct block_device *bdev; | |
212 | unsigned int major; | |
213 | ||
e02aaf17 | 214 | bdev = vdev_lookup_bdev(device); |
6c285672 JL |
215 | if (IS_ERR(bdev)) |
216 | return (B_FALSE); | |
217 | ||
218 | major = MAJOR(bdev->bd_dev); | |
219 | bdput(bdev); | |
220 | ||
221 | if (major == zvol_major) | |
ce37ebd2 | 222 | return (B_TRUE); |
6c285672 JL |
223 | |
224 | return (B_FALSE); | |
225 | } | |
226 | ||
60101509 BB |
227 | /* |
228 | * ZFS_IOC_CREATE callback handles dmu zvol and zap object creation. | |
229 | */ | |
230 | void | |
231 | zvol_create_cb(objset_t *os, void *arg, cred_t *cr, dmu_tx_t *tx) | |
232 | { | |
233 | zfs_creat_t *zct = arg; | |
234 | nvlist_t *nvprops = zct->zct_props; | |
235 | int error; | |
236 | uint64_t volblocksize, volsize; | |
237 | ||
238 | VERIFY(nvlist_lookup_uint64(nvprops, | |
239 | zfs_prop_to_name(ZFS_PROP_VOLSIZE), &volsize) == 0); | |
240 | if (nvlist_lookup_uint64(nvprops, | |
241 | zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), &volblocksize) != 0) | |
242 | volblocksize = zfs_prop_default_numeric(ZFS_PROP_VOLBLOCKSIZE); | |
243 | ||
244 | /* | |
245 | * These properties must be removed from the list so the generic | |
246 | * property setting step won't apply to them. | |
247 | */ | |
248 | VERIFY(nvlist_remove_all(nvprops, | |
249 | zfs_prop_to_name(ZFS_PROP_VOLSIZE)) == 0); | |
250 | (void) nvlist_remove_all(nvprops, | |
251 | zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE)); | |
252 | ||
253 | error = dmu_object_claim(os, ZVOL_OBJ, DMU_OT_ZVOL, volblocksize, | |
254 | DMU_OT_NONE, 0, tx); | |
255 | ASSERT(error == 0); | |
256 | ||
257 | error = zap_create_claim(os, ZVOL_ZAP_OBJ, DMU_OT_ZVOL_PROP, | |
258 | DMU_OT_NONE, 0, tx); | |
259 | ASSERT(error == 0); | |
260 | ||
261 | error = zap_update(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize, tx); | |
262 | ASSERT(error == 0); | |
263 | } | |
264 | ||
265 | /* | |
266 | * ZFS_IOC_OBJSET_STATS entry point. | |
267 | */ | |
268 | int | |
269 | zvol_get_stats(objset_t *os, nvlist_t *nv) | |
270 | { | |
271 | int error; | |
272 | dmu_object_info_t *doi; | |
273 | uint64_t val; | |
274 | ||
275 | error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &val); | |
276 | if (error) | |
ce37ebd2 | 277 | return (SET_ERROR(error)); |
60101509 BB |
278 | |
279 | dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_VOLSIZE, val); | |
ce37ebd2 | 280 | doi = kmem_alloc(sizeof (dmu_object_info_t), KM_SLEEP); |
60101509 BB |
281 | error = dmu_object_info(os, ZVOL_OBJ, doi); |
282 | ||
283 | if (error == 0) { | |
284 | dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_VOLBLOCKSIZE, | |
285 | doi->doi_data_block_size); | |
286 | } | |
287 | ||
ce37ebd2 | 288 | kmem_free(doi, sizeof (dmu_object_info_t)); |
60101509 | 289 | |
ce37ebd2 | 290 | return (SET_ERROR(error)); |
60101509 BB |
291 | } |
292 | ||
35d3e322 BB |
293 | static void |
294 | zvol_size_changed(zvol_state_t *zv, uint64_t volsize) | |
295 | { | |
296 | struct block_device *bdev; | |
297 | ||
298 | bdev = bdget_disk(zv->zv_disk, 0); | |
299 | if (bdev == NULL) | |
300 | return; | |
35d3e322 BB |
301 | set_capacity(zv->zv_disk, volsize >> 9); |
302 | zv->zv_volsize = volsize; | |
303 | check_disk_size_change(zv->zv_disk, bdev); | |
35d3e322 BB |
304 | |
305 | bdput(bdev); | |
306 | } | |
307 | ||
60101509 BB |
308 | /* |
309 | * Sanity check volume size. | |
310 | */ | |
311 | int | |
312 | zvol_check_volsize(uint64_t volsize, uint64_t blocksize) | |
313 | { | |
314 | if (volsize == 0) | |
2e528b49 | 315 | return (SET_ERROR(EINVAL)); |
60101509 BB |
316 | |
317 | if (volsize % blocksize != 0) | |
2e528b49 | 318 | return (SET_ERROR(EINVAL)); |
60101509 BB |
319 | |
320 | #ifdef _ILP32 | |
82ec9d41 | 321 | if (volsize - 1 > SPEC_MAXOFFSET_T) |
2e528b49 | 322 | return (SET_ERROR(EOVERFLOW)); |
60101509 BB |
323 | #endif |
324 | return (0); | |
325 | } | |
326 | ||
327 | /* | |
328 | * Ensure the zap is flushed then inform the VFS of the capacity change. | |
329 | */ | |
330 | static int | |
35d3e322 | 331 | zvol_update_volsize(uint64_t volsize, objset_t *os) |
60101509 | 332 | { |
60101509 BB |
333 | dmu_tx_t *tx; |
334 | int error; | |
513168ab | 335 | uint64_t txg; |
60101509 | 336 | |
df554c14 | 337 | tx = dmu_tx_create(os); |
60101509 | 338 | dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL); |
19d55079 | 339 | dmu_tx_mark_netfree(tx); |
60101509 BB |
340 | error = dmu_tx_assign(tx, TXG_WAIT); |
341 | if (error) { | |
342 | dmu_tx_abort(tx); | |
ce37ebd2 | 343 | return (SET_ERROR(error)); |
60101509 | 344 | } |
513168ab | 345 | txg = dmu_tx_get_txg(tx); |
60101509 | 346 | |
df554c14 | 347 | error = zap_update(os, ZVOL_ZAP_OBJ, "size", 8, 1, |
60101509 BB |
348 | &volsize, tx); |
349 | dmu_tx_commit(tx); | |
350 | ||
513168ab | 351 | txg_wait_synced(dmu_objset_pool(os), txg); |
352 | ||
35d3e322 BB |
353 | if (error == 0) |
354 | error = dmu_free_long_range(os, | |
355 | ZVOL_OBJ, volsize, DMU_OBJECT_END); | |
60101509 | 356 | |
35d3e322 BB |
357 | return (error); |
358 | } | |
60101509 | 359 | |
35d3e322 BB |
360 | static int |
361 | zvol_update_live_volsize(zvol_state_t *zv, uint64_t volsize) | |
362 | { | |
363 | zvol_size_changed(zv, volsize); | |
60101509 | 364 | |
35d3e322 BB |
365 | /* |
366 | * We should post a event here describing the expansion. However, | |
367 | * the zfs_ereport_post() interface doesn't nicely support posting | |
368 | * events for zvols, it assumes events relate to vdevs or zios. | |
369 | */ | |
60101509 BB |
370 | |
371 | return (0); | |
372 | } | |
373 | ||
374 | /* | |
375 | * Set ZFS_PROP_VOLSIZE set entry point. | |
376 | */ | |
377 | int | |
378 | zvol_set_volsize(const char *name, uint64_t volsize) | |
379 | { | |
35d3e322 | 380 | zvol_state_t *zv = NULL; |
60101509 | 381 | objset_t *os = NULL; |
60101509 | 382 | int error; |
35d3e322 BB |
383 | dmu_object_info_t *doi; |
384 | uint64_t readonly; | |
385 | boolean_t owned = B_FALSE; | |
60101509 | 386 | |
13fe0198 MA |
387 | error = dsl_prop_get_integer(name, |
388 | zfs_prop_to_name(ZFS_PROP_READONLY), &readonly, NULL); | |
389 | if (error != 0) | |
ce37ebd2 | 390 | return (SET_ERROR(error)); |
13fe0198 | 391 | if (readonly) |
2e528b49 | 392 | return (SET_ERROR(EROFS)); |
13fe0198 | 393 | |
60101509 | 394 | mutex_enter(&zvol_state_lock); |
60101509 | 395 | zv = zvol_find_by_name(name); |
5559ba09 BP |
396 | if (zv != NULL) |
397 | mutex_enter(&zv->zv_state_lock); | |
398 | mutex_exit(&zvol_state_lock); | |
35d3e322 BB |
399 | |
400 | if (zv == NULL || zv->zv_objset == NULL) { | |
401 | if ((error = dmu_objset_own(name, DMU_OST_ZVOL, B_FALSE, | |
402 | FTAG, &os)) != 0) { | |
5559ba09 BP |
403 | if (zv != NULL) |
404 | mutex_exit(&zv->zv_state_lock); | |
35d3e322 BB |
405 | return (SET_ERROR(error)); |
406 | } | |
407 | owned = B_TRUE; | |
408 | if (zv != NULL) | |
409 | zv->zv_objset = os; | |
410 | } else { | |
040dab99 | 411 | rw_enter(&zv->zv_suspend_lock, RW_READER); |
35d3e322 | 412 | os = zv->zv_objset; |
60101509 BB |
413 | } |
414 | ||
ce37ebd2 | 415 | doi = kmem_alloc(sizeof (dmu_object_info_t), KM_SLEEP); |
60101509 | 416 | |
ce37ebd2 BB |
417 | if ((error = dmu_object_info(os, ZVOL_OBJ, doi)) || |
418 | (error = zvol_check_volsize(volsize, doi->doi_data_block_size))) | |
35d3e322 | 419 | goto out; |
60101509 | 420 | |
35d3e322 | 421 | error = zvol_update_volsize(volsize, os); |
60101509 | 422 | |
35d3e322 BB |
423 | if (error == 0 && zv != NULL) |
424 | error = zvol_update_live_volsize(zv, volsize); | |
425 | out: | |
3f7d0418 | 426 | kmem_free(doi, sizeof (dmu_object_info_t)); |
427 | ||
35d3e322 BB |
428 | if (owned) { |
429 | dmu_objset_disown(os, FTAG); | |
430 | if (zv != NULL) | |
431 | zv->zv_objset = NULL; | |
040dab99 CC |
432 | } else { |
433 | rw_exit(&zv->zv_suspend_lock); | |
35d3e322 | 434 | } |
5559ba09 BP |
435 | |
436 | if (zv != NULL) | |
437 | mutex_exit(&zv->zv_state_lock); | |
438 | return (SET_ERROR(error)); | |
60101509 BB |
439 | } |
440 | ||
441 | /* | |
442 | * Sanity check volume block size. | |
443 | */ | |
444 | int | |
4cb7b9c5 | 445 | zvol_check_volblocksize(const char *name, uint64_t volblocksize) |
60101509 | 446 | { |
4cb7b9c5 BB |
447 | /* Record sizes above 128k need the feature to be enabled */ |
448 | if (volblocksize > SPA_OLD_MAXBLOCKSIZE) { | |
449 | spa_t *spa; | |
450 | int error; | |
451 | ||
452 | if ((error = spa_open(name, &spa, FTAG)) != 0) | |
453 | return (error); | |
454 | ||
455 | if (!spa_feature_is_enabled(spa, SPA_FEATURE_LARGE_BLOCKS)) { | |
456 | spa_close(spa, FTAG); | |
457 | return (SET_ERROR(ENOTSUP)); | |
458 | } | |
459 | ||
460 | /* | |
461 | * We don't allow setting the property above 1MB, | |
462 | * unless the tunable has been changed. | |
463 | */ | |
464 | if (volblocksize > zfs_max_recordsize) | |
465 | return (SET_ERROR(EDOM)); | |
466 | ||
467 | spa_close(spa, FTAG); | |
468 | } | |
469 | ||
60101509 BB |
470 | if (volblocksize < SPA_MINBLOCKSIZE || |
471 | volblocksize > SPA_MAXBLOCKSIZE || | |
472 | !ISP2(volblocksize)) | |
2e528b49 | 473 | return (SET_ERROR(EDOM)); |
60101509 BB |
474 | |
475 | return (0); | |
476 | } | |
477 | ||
478 | /* | |
479 | * Set ZFS_PROP_VOLBLOCKSIZE set entry point. | |
480 | */ | |
481 | int | |
482 | zvol_set_volblocksize(const char *name, uint64_t volblocksize) | |
483 | { | |
484 | zvol_state_t *zv; | |
485 | dmu_tx_t *tx; | |
486 | int error; | |
487 | ||
488 | mutex_enter(&zvol_state_lock); | |
489 | ||
490 | zv = zvol_find_by_name(name); | |
491 | if (zv == NULL) { | |
5559ba09 BP |
492 | mutex_exit(&zvol_state_lock); |
493 | return (SET_ERROR(ENXIO)); | |
60101509 | 494 | } |
5559ba09 BP |
495 | mutex_enter(&zv->zv_state_lock); |
496 | mutex_exit(&zvol_state_lock); | |
60101509 | 497 | |
ba6a2402 | 498 | if (zv->zv_flags & ZVOL_RDONLY) { |
5559ba09 BP |
499 | mutex_exit(&zv->zv_state_lock); |
500 | return (SET_ERROR(EROFS)); | |
60101509 BB |
501 | } |
502 | ||
040dab99 CC |
503 | rw_enter(&zv->zv_suspend_lock, RW_READER); |
504 | ||
60101509 BB |
505 | tx = dmu_tx_create(zv->zv_objset); |
506 | dmu_tx_hold_bonus(tx, ZVOL_OBJ); | |
507 | error = dmu_tx_assign(tx, TXG_WAIT); | |
508 | if (error) { | |
509 | dmu_tx_abort(tx); | |
510 | } else { | |
511 | error = dmu_object_set_blocksize(zv->zv_objset, ZVOL_OBJ, | |
512 | volblocksize, 0, tx); | |
513 | if (error == ENOTSUP) | |
2e528b49 | 514 | error = SET_ERROR(EBUSY); |
60101509 BB |
515 | dmu_tx_commit(tx); |
516 | if (error == 0) | |
517 | zv->zv_volblocksize = volblocksize; | |
518 | } | |
040dab99 | 519 | rw_exit(&zv->zv_suspend_lock); |
5559ba09 BP |
520 | |
521 | mutex_exit(&zv->zv_state_lock); | |
60101509 | 522 | |
ce37ebd2 | 523 | return (SET_ERROR(error)); |
60101509 BB |
524 | } |
525 | ||
460a0213 DM |
526 | /* |
527 | * Replay a TX_TRUNCATE ZIL transaction if asked. TX_TRUNCATE is how we | |
528 | * implement DKIOCFREE/free-long-range. | |
529 | */ | |
530 | static int | |
531 | zvol_replay_truncate(zvol_state_t *zv, lr_truncate_t *lr, boolean_t byteswap) | |
532 | { | |
533 | uint64_t offset, length; | |
534 | ||
535 | if (byteswap) | |
536 | byteswap_uint64_array(lr, sizeof (*lr)); | |
537 | ||
538 | offset = lr->lr_offset; | |
539 | length = lr->lr_length; | |
540 | ||
541 | return (dmu_free_long_range(zv->zv_objset, ZVOL_OBJ, offset, length)); | |
542 | } | |
543 | ||
60101509 BB |
544 | /* |
545 | * Replay a TX_WRITE ZIL transaction that didn't get committed | |
546 | * after a system failure | |
547 | */ | |
548 | static int | |
549 | zvol_replay_write(zvol_state_t *zv, lr_write_t *lr, boolean_t byteswap) | |
550 | { | |
551 | objset_t *os = zv->zv_objset; | |
552 | char *data = (char *)(lr + 1); /* data follows lr_write_t */ | |
553 | uint64_t off = lr->lr_offset; | |
554 | uint64_t len = lr->lr_length; | |
555 | dmu_tx_t *tx; | |
556 | int error; | |
557 | ||
558 | if (byteswap) | |
559 | byteswap_uint64_array(lr, sizeof (*lr)); | |
560 | ||
561 | tx = dmu_tx_create(os); | |
562 | dmu_tx_hold_write(tx, ZVOL_OBJ, off, len); | |
563 | error = dmu_tx_assign(tx, TXG_WAIT); | |
564 | if (error) { | |
565 | dmu_tx_abort(tx); | |
566 | } else { | |
567 | dmu_write(os, ZVOL_OBJ, off, len, data, tx); | |
568 | dmu_tx_commit(tx); | |
569 | } | |
570 | ||
ce37ebd2 | 571 | return (SET_ERROR(error)); |
60101509 BB |
572 | } |
573 | ||
574 | static int | |
575 | zvol_replay_err(zvol_state_t *zv, lr_t *lr, boolean_t byteswap) | |
576 | { | |
2e528b49 | 577 | return (SET_ERROR(ENOTSUP)); |
60101509 BB |
578 | } |
579 | ||
580 | /* | |
581 | * Callback vectors for replaying records. | |
460a0213 | 582 | * Only TX_WRITE and TX_TRUNCATE are needed for zvol. |
60101509 | 583 | */ |
b01615d5 RY |
584 | zil_replay_func_t zvol_replay_vector[TX_MAX_TYPE] = { |
585 | (zil_replay_func_t)zvol_replay_err, /* no such transaction type */ | |
586 | (zil_replay_func_t)zvol_replay_err, /* TX_CREATE */ | |
587 | (zil_replay_func_t)zvol_replay_err, /* TX_MKDIR */ | |
588 | (zil_replay_func_t)zvol_replay_err, /* TX_MKXATTR */ | |
589 | (zil_replay_func_t)zvol_replay_err, /* TX_SYMLINK */ | |
590 | (zil_replay_func_t)zvol_replay_err, /* TX_REMOVE */ | |
591 | (zil_replay_func_t)zvol_replay_err, /* TX_RMDIR */ | |
592 | (zil_replay_func_t)zvol_replay_err, /* TX_LINK */ | |
593 | (zil_replay_func_t)zvol_replay_err, /* TX_RENAME */ | |
594 | (zil_replay_func_t)zvol_replay_write, /* TX_WRITE */ | |
460a0213 | 595 | (zil_replay_func_t)zvol_replay_truncate, /* TX_TRUNCATE */ |
b01615d5 RY |
596 | (zil_replay_func_t)zvol_replay_err, /* TX_SETATTR */ |
597 | (zil_replay_func_t)zvol_replay_err, /* TX_ACL */ | |
60101509 BB |
598 | }; |
599 | ||
600 | /* | |
601 | * zvol_log_write() handles synchronous writes using TX_WRITE ZIL transactions. | |
602 | * | |
603 | * We store data in the log buffers if it's small enough. | |
604 | * Otherwise we will later flush the data out via dmu_sync(). | |
605 | */ | |
606 | ssize_t zvol_immediate_write_sz = 32768; | |
607 | ||
608 | static void | |
ce37ebd2 BB |
609 | zvol_log_write(zvol_state_t *zv, dmu_tx_t *tx, uint64_t offset, |
610 | uint64_t size, int sync) | |
60101509 BB |
611 | { |
612 | uint32_t blocksize = zv->zv_volblocksize; | |
613 | zilog_t *zilog = zv->zv_zilog; | |
614 | boolean_t slogging; | |
ab85f845 | 615 | ssize_t immediate_write_sz; |
60101509 BB |
616 | |
617 | if (zil_replaying(zilog, tx)) | |
618 | return; | |
619 | ||
ab85f845 | 620 | immediate_write_sz = (zilog->zl_logbias == ZFS_LOGBIAS_THROUGHPUT) |
02730c33 | 621 | ? 0 : zvol_immediate_write_sz; |
ab85f845 | 622 | slogging = spa_has_slogs(zilog->zl_spa) && |
02730c33 | 623 | (zilog->zl_logbias == ZFS_LOGBIAS_LATENCY); |
60101509 BB |
624 | |
625 | while (size) { | |
626 | itx_t *itx; | |
627 | lr_write_t *lr; | |
628 | ssize_t len; | |
629 | itx_wr_state_t write_state; | |
630 | ||
631 | /* | |
632 | * Unlike zfs_log_write() we can be called with | |
633 | * up to DMU_MAX_ACCESS/2 (5MB) writes. | |
634 | */ | |
ab85f845 | 635 | if (blocksize > immediate_write_sz && !slogging && |
60101509 BB |
636 | size >= blocksize && offset % blocksize == 0) { |
637 | write_state = WR_INDIRECT; /* uses dmu_sync */ | |
638 | len = blocksize; | |
639 | } else if (sync) { | |
640 | write_state = WR_COPIED; | |
641 | len = MIN(ZIL_MAX_LOG_DATA, size); | |
642 | } else { | |
643 | write_state = WR_NEED_COPY; | |
644 | len = MIN(ZIL_MAX_LOG_DATA, size); | |
645 | } | |
646 | ||
647 | itx = zil_itx_create(TX_WRITE, sizeof (*lr) + | |
648 | (write_state == WR_COPIED ? len : 0)); | |
649 | lr = (lr_write_t *)&itx->itx_lr; | |
650 | if (write_state == WR_COPIED && dmu_read(zv->zv_objset, | |
651 | ZVOL_OBJ, offset, len, lr+1, DMU_READ_NO_PREFETCH) != 0) { | |
652 | zil_itx_destroy(itx); | |
653 | itx = zil_itx_create(TX_WRITE, sizeof (*lr)); | |
654 | lr = (lr_write_t *)&itx->itx_lr; | |
655 | write_state = WR_NEED_COPY; | |
656 | } | |
657 | ||
658 | itx->itx_wr_state = write_state; | |
659 | if (write_state == WR_NEED_COPY) | |
660 | itx->itx_sod += len; | |
661 | lr->lr_foid = ZVOL_OBJ; | |
662 | lr->lr_offset = offset; | |
663 | lr->lr_length = len; | |
664 | lr->lr_blkoff = 0; | |
665 | BP_ZERO(&lr->lr_blkptr); | |
666 | ||
667 | itx->itx_private = zv; | |
668 | itx->itx_sync = sync; | |
669 | ||
670 | (void) zil_itx_assign(zilog, itx, tx); | |
671 | ||
672 | offset += len; | |
673 | size -= len; | |
674 | } | |
675 | } | |
676 | ||
692e55b8 CC |
677 | typedef struct zv_request { |
678 | zvol_state_t *zv; | |
679 | struct bio *bio; | |
680 | rl_t *rl; | |
681 | } zv_request_t; | |
682 | ||
683 | static void | |
684 | uio_from_bio(uio_t *uio, struct bio *bio) | |
60101509 | 685 | { |
692e55b8 CC |
686 | uio->uio_bvec = &bio->bi_io_vec[BIO_BI_IDX(bio)]; |
687 | uio->uio_skip = BIO_BI_SKIP(bio); | |
688 | uio->uio_resid = BIO_BI_SIZE(bio); | |
689 | uio->uio_iovcnt = bio->bi_vcnt - BIO_BI_IDX(bio); | |
690 | uio->uio_loffset = BIO_BI_SECTOR(bio) << 9; | |
691 | uio->uio_limit = MAXOFFSET_T; | |
692 | uio->uio_segflg = UIO_BVEC; | |
693 | } | |
694 | ||
695 | static void | |
696 | zvol_write(void *arg) | |
697 | { | |
698 | zv_request_t *zvr = arg; | |
699 | struct bio *bio = zvr->bio; | |
700 | uio_t uio; | |
701 | zvol_state_t *zv = zvr->zv; | |
a765a34a | 702 | uint64_t volsize = zv->zv_volsize; |
692e55b8 | 703 | boolean_t sync; |
a765a34a | 704 | int error = 0; |
692e55b8 CC |
705 | unsigned long start_jif; |
706 | ||
707 | uio_from_bio(&uio, bio); | |
60101509 | 708 | |
5428dc51 BP |
709 | ASSERT(zv && zv->zv_open_count > 0); |
710 | ||
692e55b8 CC |
711 | start_jif = jiffies; |
712 | generic_start_io_acct(WRITE, bio_sectors(bio), &zv->zv_disk->part0); | |
b18019d2 | 713 | |
692e55b8 CC |
714 | sync = bio_is_fua(bio) || zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS; |
715 | ||
716 | while (uio.uio_resid > 0 && uio.uio_loffset < volsize) { | |
717 | uint64_t bytes = MIN(uio.uio_resid, DMU_MAX_ACCESS >> 1); | |
718 | uint64_t off = uio.uio_loffset; | |
a765a34a | 719 | dmu_tx_t *tx = dmu_tx_create(zv->zv_objset); |
b18019d2 | 720 | |
a765a34a RY |
721 | if (bytes > volsize - off) /* don't write past the end */ |
722 | bytes = volsize - off; | |
2727b9d3 | 723 | |
a765a34a | 724 | dmu_tx_hold_write(tx, ZVOL_OBJ, off, bytes); |
60101509 | 725 | |
a765a34a RY |
726 | /* This will only fail for ENOSPC */ |
727 | error = dmu_tx_assign(tx, TXG_WAIT); | |
728 | if (error) { | |
729 | dmu_tx_abort(tx); | |
730 | break; | |
731 | } | |
692e55b8 | 732 | error = dmu_write_uio_dbuf(zv->zv_dbuf, &uio, bytes, tx); |
a765a34a RY |
733 | if (error == 0) |
734 | zvol_log_write(zv, tx, off, bytes, sync); | |
735 | dmu_tx_commit(tx); | |
60101509 | 736 | |
a765a34a RY |
737 | if (error) |
738 | break; | |
60101509 | 739 | } |
692e55b8 | 740 | zfs_range_unlock(zvr->rl); |
a765a34a | 741 | if (sync) |
60101509 | 742 | zil_commit(zv->zv_zilog, ZVOL_OBJ); |
692e55b8 CC |
743 | |
744 | rw_exit(&zv->zv_suspend_lock); | |
745 | generic_end_io_acct(WRITE, &zv->zv_disk->part0, start_jif); | |
746 | BIO_END_IO(bio, -error); | |
747 | kmem_free(zvr, sizeof (zv_request_t)); | |
60101509 BB |
748 | } |
749 | ||
460a0213 DM |
750 | /* |
751 | * Log a DKIOCFREE/free-long-range to the ZIL with TX_TRUNCATE. | |
752 | */ | |
753 | static void | |
754 | zvol_log_truncate(zvol_state_t *zv, dmu_tx_t *tx, uint64_t off, uint64_t len, | |
755 | boolean_t sync) | |
756 | { | |
757 | itx_t *itx; | |
758 | lr_truncate_t *lr; | |
759 | zilog_t *zilog = zv->zv_zilog; | |
760 | ||
761 | if (zil_replaying(zilog, tx)) | |
762 | return; | |
763 | ||
764 | itx = zil_itx_create(TX_TRUNCATE, sizeof (*lr)); | |
765 | lr = (lr_truncate_t *)&itx->itx_lr; | |
766 | lr->lr_foid = ZVOL_OBJ; | |
767 | lr->lr_offset = off; | |
768 | lr->lr_length = len; | |
769 | ||
770 | itx->itx_sync = sync; | |
771 | zil_itx_assign(zilog, itx, tx); | |
772 | } | |
773 | ||
692e55b8 CC |
774 | static void |
775 | zvol_discard(void *arg) | |
30930fba | 776 | { |
692e55b8 CC |
777 | zv_request_t *zvr = arg; |
778 | struct bio *bio = zvr->bio; | |
779 | zvol_state_t *zv = zvr->zv; | |
37f9dac5 RY |
780 | uint64_t start = BIO_BI_SECTOR(bio) << 9; |
781 | uint64_t size = BIO_BI_SIZE(bio); | |
782 | uint64_t end = start + size; | |
692e55b8 | 783 | int error = 0; |
460a0213 | 784 | dmu_tx_t *tx; |
692e55b8 | 785 | unsigned long start_jif; |
30930fba | 786 | |
5428dc51 BP |
787 | ASSERT(zv && zv->zv_open_count > 0); |
788 | ||
692e55b8 CC |
789 | start_jif = jiffies; |
790 | generic_start_io_acct(WRITE, bio_sectors(bio), &zv->zv_disk->part0); | |
791 | ||
792 | if (end > zv->zv_volsize) { | |
793 | error = SET_ERROR(EIO); | |
794 | goto out; | |
795 | } | |
30930fba | 796 | |
089fa91b | 797 | /* |
cf41432c BB |
798 | * Align the request to volume block boundaries when a secure erase is |
799 | * not required. This will prevent dnode_free_range() from zeroing out | |
800 | * the unaligned parts which is slow (read-modify-write) and useless | |
801 | * since we are not freeing any space by doing so. | |
089fa91b | 802 | */ |
cf41432c | 803 | if (!bio_is_secure_erase(bio)) { |
fa565676 RY |
804 | start = P2ROUNDUP(start, zv->zv_volblocksize); |
805 | end = P2ALIGN(end, zv->zv_volblocksize); | |
f52ebcb3 | 806 | size = end - start; |
fa565676 | 807 | } |
089fa91b | 808 | |
37f9dac5 | 809 | if (start >= end) |
692e55b8 | 810 | goto out; |
30930fba | 811 | |
460a0213 DM |
812 | tx = dmu_tx_create(zv->zv_objset); |
813 | dmu_tx_mark_netfree(tx); | |
814 | error = dmu_tx_assign(tx, TXG_WAIT); | |
815 | if (error != 0) { | |
816 | dmu_tx_abort(tx); | |
817 | } else { | |
818 | zvol_log_truncate(zv, tx, start, size, B_TRUE); | |
819 | dmu_tx_commit(tx); | |
820 | error = dmu_free_long_range(zv->zv_objset, | |
821 | ZVOL_OBJ, start, size); | |
822 | } | |
30930fba | 823 | |
692e55b8 CC |
824 | out: |
825 | zfs_range_unlock(zvr->rl); | |
826 | rw_exit(&zv->zv_suspend_lock); | |
827 | generic_end_io_acct(WRITE, &zv->zv_disk->part0, start_jif); | |
828 | BIO_END_IO(bio, -error); | |
829 | kmem_free(zvr, sizeof (zv_request_t)); | |
30930fba | 830 | } |
30930fba | 831 | |
692e55b8 CC |
832 | static void |
833 | zvol_read(void *arg) | |
60101509 | 834 | { |
692e55b8 CC |
835 | zv_request_t *zvr = arg; |
836 | struct bio *bio = zvr->bio; | |
837 | uio_t uio; | |
838 | zvol_state_t *zv = zvr->zv; | |
a765a34a | 839 | uint64_t volsize = zv->zv_volsize; |
a765a34a | 840 | int error = 0; |
692e55b8 CC |
841 | unsigned long start_jif; |
842 | ||
843 | uio_from_bio(&uio, bio); | |
b18019d2 | 844 | |
5428dc51 BP |
845 | ASSERT(zv && zv->zv_open_count > 0); |
846 | ||
692e55b8 CC |
847 | start_jif = jiffies; |
848 | generic_start_io_acct(READ, bio_sectors(bio), &zv->zv_disk->part0); | |
849 | ||
850 | while (uio.uio_resid > 0 && uio.uio_loffset < volsize) { | |
851 | uint64_t bytes = MIN(uio.uio_resid, DMU_MAX_ACCESS >> 1); | |
60101509 | 852 | |
a765a34a | 853 | /* don't read past the end */ |
692e55b8 CC |
854 | if (bytes > volsize - uio.uio_loffset) |
855 | bytes = volsize - uio.uio_loffset; | |
60101509 | 856 | |
692e55b8 | 857 | error = dmu_read_uio_dbuf(zv->zv_dbuf, &uio, bytes); |
a765a34a RY |
858 | if (error) { |
859 | /* convert checksum errors into IO errors */ | |
860 | if (error == ECKSUM) | |
861 | error = SET_ERROR(EIO); | |
862 | break; | |
863 | } | |
864 | } | |
692e55b8 CC |
865 | zfs_range_unlock(zvr->rl); |
866 | ||
867 | rw_exit(&zv->zv_suspend_lock); | |
868 | generic_end_io_acct(READ, &zv->zv_disk->part0, start_jif); | |
869 | BIO_END_IO(bio, -error); | |
870 | kmem_free(zvr, sizeof (zv_request_t)); | |
60101509 BB |
871 | } |
872 | ||
37f9dac5 RY |
873 | static MAKE_REQUEST_FN_RET |
874 | zvol_request(struct request_queue *q, struct bio *bio) | |
60101509 BB |
875 | { |
876 | zvol_state_t *zv = q->queuedata; | |
37f9dac5 | 877 | fstrans_cookie_t cookie = spl_fstrans_mark(); |
692e55b8 CC |
878 | uint64_t offset = BIO_BI_SECTOR(bio) << 9; |
879 | uint64_t size = BIO_BI_SIZE(bio); | |
8198d18c | 880 | int rw = bio_data_dir(bio); |
692e55b8 | 881 | zv_request_t *zvr; |
a765a34a | 882 | |
692e55b8 | 883 | if (bio_has_data(bio) && offset + size > zv->zv_volsize) { |
37f9dac5 | 884 | printk(KERN_INFO |
a765a34a | 885 | "%s: bad access: offset=%llu, size=%lu\n", |
37f9dac5 | 886 | zv->zv_disk->disk_name, |
692e55b8 CC |
887 | (long long unsigned)offset, |
888 | (long unsigned)size); | |
37f9dac5 | 889 | |
692e55b8 CC |
890 | BIO_END_IO(bio, -SET_ERROR(EIO)); |
891 | goto out; | |
892 | } | |
8198d18c RY |
893 | |
894 | if (rw == WRITE) { | |
37f9dac5 | 895 | if (unlikely(zv->zv_flags & ZVOL_RDONLY)) { |
692e55b8 CC |
896 | BIO_END_IO(bio, -SET_ERROR(EROFS)); |
897 | goto out; | |
60101509 BB |
898 | } |
899 | ||
692e55b8 CC |
900 | /* |
901 | * To be released in the I/O function. See the comment on | |
902 | * zfs_range_lock below. | |
903 | */ | |
904 | rw_enter(&zv->zv_suspend_lock, RW_READER); | |
905 | ||
906 | /* bio marked as FLUSH need to flush before write */ | |
907 | if (bio_is_flush(bio)) | |
908 | zil_commit(zv->zv_zilog, ZVOL_OBJ); | |
909 | ||
910 | /* Some requests are just for flush and nothing else. */ | |
911 | if (size == 0) { | |
912 | rw_exit(&zv->zv_suspend_lock); | |
913 | BIO_END_IO(bio, 0); | |
914 | goto out; | |
37f9dac5 | 915 | } |
60101509 | 916 | |
692e55b8 CC |
917 | zvr = kmem_alloc(sizeof (zv_request_t), KM_SLEEP); |
918 | zvr->zv = zv; | |
919 | zvr->bio = bio; | |
920 | ||
a765a34a | 921 | /* |
692e55b8 CC |
922 | * To be released in the I/O function. Since the I/O functions |
923 | * are asynchronous, we take it here synchronously to make | |
924 | * sure overlapped I/Os are properly ordered. | |
a765a34a | 925 | */ |
692e55b8 CC |
926 | zvr->rl = zfs_range_lock(&zv->zv_range_lock, offset, size, |
927 | RL_WRITER); | |
928 | if (bio_is_discard(bio) || bio_is_secure_erase(bio)) { | |
929 | if (zvol_request_sync || taskq_dispatch(zvol_taskq, | |
930 | zvol_discard, zvr, TQ_SLEEP) == TASKQID_INVALID) | |
931 | zvol_discard(zvr); | |
932 | } else { | |
933 | if (zvol_request_sync || taskq_dispatch(zvol_taskq, | |
934 | zvol_write, zvr, TQ_SLEEP) == TASKQID_INVALID) | |
935 | zvol_write(zvr); | |
a765a34a | 936 | } |
692e55b8 CC |
937 | } else { |
938 | zvr = kmem_alloc(sizeof (zv_request_t), KM_SLEEP); | |
939 | zvr->zv = zv; | |
940 | zvr->bio = bio; | |
a765a34a | 941 | |
692e55b8 | 942 | rw_enter(&zv->zv_suspend_lock, RW_READER); |
30930fba | 943 | |
692e55b8 CC |
944 | zvr->rl = zfs_range_lock(&zv->zv_range_lock, offset, size, |
945 | RL_READER); | |
946 | if (zvol_request_sync || taskq_dispatch(zvol_taskq, | |
947 | zvol_read, zvr, TQ_SLEEP) == TASKQID_INVALID) | |
948 | zvol_read(zvr); | |
949 | } | |
950 | ||
951 | out: | |
37f9dac5 RY |
952 | spl_fstrans_unmark(cookie); |
953 | #ifdef HAVE_MAKE_REQUEST_FN_RET_INT | |
954 | return (0); | |
1a093716 CC |
955 | #elif defined(HAVE_MAKE_REQUEST_FN_RET_QC) |
956 | return (BLK_QC_T_NONE); | |
37f9dac5 | 957 | #endif |
60101509 BB |
958 | } |
959 | ||
960 | static void | |
961 | zvol_get_done(zgd_t *zgd, int error) | |
962 | { | |
963 | if (zgd->zgd_db) | |
964 | dmu_buf_rele(zgd->zgd_db, zgd); | |
965 | ||
966 | zfs_range_unlock(zgd->zgd_rl); | |
967 | ||
968 | if (error == 0 && zgd->zgd_bp) | |
969 | zil_add_block(zgd->zgd_zilog, zgd->zgd_bp); | |
970 | ||
971 | kmem_free(zgd, sizeof (zgd_t)); | |
972 | } | |
973 | ||
974 | /* | |
975 | * Get data to generate a TX_WRITE intent log record. | |
976 | */ | |
977 | static int | |
978 | zvol_get_data(void *arg, lr_write_t *lr, char *buf, zio_t *zio) | |
979 | { | |
980 | zvol_state_t *zv = arg; | |
981 | objset_t *os = zv->zv_objset; | |
03c6040b | 982 | uint64_t object = ZVOL_OBJ; |
60101509 BB |
983 | uint64_t offset = lr->lr_offset; |
984 | uint64_t size = lr->lr_length; | |
03c6040b | 985 | blkptr_t *bp = &lr->lr_blkptr; |
60101509 BB |
986 | dmu_buf_t *db; |
987 | zgd_t *zgd; | |
988 | int error; | |
989 | ||
990 | ASSERT(zio != NULL); | |
991 | ASSERT(size != 0); | |
992 | ||
79c76d5b | 993 | zgd = (zgd_t *)kmem_zalloc(sizeof (zgd_t), KM_SLEEP); |
60101509 | 994 | zgd->zgd_zilog = zv->zv_zilog; |
d88895a0 CC |
995 | zgd->zgd_rl = zfs_range_lock(&zv->zv_range_lock, offset, size, |
996 | RL_READER); | |
60101509 BB |
997 | |
998 | /* | |
999 | * Write records come in two flavors: immediate and indirect. | |
1000 | * For small writes it's cheaper to store the data with the | |
1001 | * log record (immediate); for large writes it's cheaper to | |
1002 | * sync the data and get a pointer to it (indirect) so that | |
1003 | * we don't have to write the data twice. | |
1004 | */ | |
1005 | if (buf != NULL) { /* immediate write */ | |
03c6040b | 1006 | error = dmu_read(os, object, offset, size, buf, |
60101509 BB |
1007 | DMU_READ_NO_PREFETCH); |
1008 | } else { | |
1009 | size = zv->zv_volblocksize; | |
1010 | offset = P2ALIGN_TYPED(offset, size, uint64_t); | |
03c6040b | 1011 | error = dmu_buf_hold(os, object, offset, zgd, &db, |
60101509 BB |
1012 | DMU_READ_NO_PREFETCH); |
1013 | if (error == 0) { | |
03c6040b GW |
1014 | blkptr_t *obp = dmu_buf_get_blkptr(db); |
1015 | if (obp) { | |
1016 | ASSERT(BP_IS_HOLE(bp)); | |
1017 | *bp = *obp; | |
1018 | } | |
1019 | ||
60101509 BB |
1020 | zgd->zgd_db = db; |
1021 | zgd->zgd_bp = &lr->lr_blkptr; | |
1022 | ||
1023 | ASSERT(db != NULL); | |
1024 | ASSERT(db->db_offset == offset); | |
1025 | ASSERT(db->db_size == size); | |
1026 | ||
1027 | error = dmu_sync(zio, lr->lr_common.lrc_txg, | |
1028 | zvol_get_done, zgd); | |
1029 | ||
1030 | if (error == 0) | |
1031 | return (0); | |
1032 | } | |
1033 | } | |
1034 | ||
1035 | zvol_get_done(zgd, error); | |
1036 | ||
ce37ebd2 | 1037 | return (SET_ERROR(error)); |
60101509 BB |
1038 | } |
1039 | ||
1040 | /* | |
d45e010d | 1041 | * The zvol_state_t's are inserted into zvol_state_list and zvol_htable. |
60101509 BB |
1042 | */ |
1043 | static void | |
d45e010d | 1044 | zvol_insert(zvol_state_t *zv) |
60101509 | 1045 | { |
60101509 | 1046 | ASSERT(MUTEX_HELD(&zvol_state_lock)); |
d45e010d CC |
1047 | ASSERT3U(MINOR(zv->zv_dev) & ZVOL_MINOR_MASK, ==, 0); |
1048 | list_insert_head(&zvol_state_list, zv); | |
1049 | hlist_add_head(&zv->zv_hlink, ZVOL_HT_HEAD(zv->zv_hash)); | |
60101509 BB |
1050 | } |
1051 | ||
1052 | /* | |
1053 | * Simply remove the zvol from to list of zvols. | |
1054 | */ | |
1055 | static void | |
d45e010d | 1056 | zvol_remove(zvol_state_t *zv) |
60101509 BB |
1057 | { |
1058 | ASSERT(MUTEX_HELD(&zvol_state_lock)); | |
d45e010d CC |
1059 | list_remove(&zvol_state_list, zv); |
1060 | hlist_del(&zv->zv_hlink); | |
60101509 BB |
1061 | } |
1062 | ||
040dab99 CC |
1063 | /* |
1064 | * Setup zv after we just own the zv->objset | |
1065 | */ | |
60101509 | 1066 | static int |
040dab99 | 1067 | zvol_setup_zv(zvol_state_t *zv) |
60101509 | 1068 | { |
60101509 BB |
1069 | uint64_t volsize; |
1070 | int error; | |
1071 | uint64_t ro; | |
040dab99 | 1072 | objset_t *os = zv->zv_objset; |
1ee159f4 BP |
1073 | |
1074 | error = dsl_prop_get_integer(zv->zv_name, "readonly", &ro, NULL); | |
1075 | if (error) | |
040dab99 | 1076 | return (SET_ERROR(error)); |
60101509 BB |
1077 | |
1078 | error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize); | |
1ee159f4 | 1079 | if (error) |
040dab99 | 1080 | return (SET_ERROR(error)); |
60101509 | 1081 | |
040dab99 | 1082 | error = dmu_bonus_hold(os, ZVOL_OBJ, zv, &zv->zv_dbuf); |
1ee159f4 | 1083 | if (error) |
040dab99 | 1084 | return (SET_ERROR(error)); |
60101509 BB |
1085 | |
1086 | set_capacity(zv->zv_disk, volsize >> 9); | |
1087 | zv->zv_volsize = volsize; | |
1088 | zv->zv_zilog = zil_open(os, zvol_get_data); | |
1089 | ||
a4430fce GW |
1090 | if (ro || dmu_objset_is_snapshot(os) || |
1091 | !spa_writeable(dmu_objset_spa(os))) { | |
babf3f9b MM |
1092 | set_disk_ro(zv->zv_disk, 1); |
1093 | zv->zv_flags |= ZVOL_RDONLY; | |
60101509 | 1094 | } else { |
babf3f9b MM |
1095 | set_disk_ro(zv->zv_disk, 0); |
1096 | zv->zv_flags &= ~ZVOL_RDONLY; | |
60101509 | 1097 | } |
040dab99 | 1098 | return (0); |
60101509 BB |
1099 | } |
1100 | ||
040dab99 CC |
1101 | /* |
1102 | * Shutdown every zv_objset related stuff except zv_objset itself. | |
1103 | * The is the reverse of zvol_setup_zv. | |
1104 | */ | |
60101509 | 1105 | static void |
040dab99 | 1106 | zvol_shutdown_zv(zvol_state_t *zv) |
60101509 BB |
1107 | { |
1108 | zil_close(zv->zv_zilog); | |
1109 | zv->zv_zilog = NULL; | |
04434775 | 1110 | |
040dab99 | 1111 | dmu_buf_rele(zv->zv_dbuf, zv); |
60101509 | 1112 | zv->zv_dbuf = NULL; |
04434775 MA |
1113 | |
1114 | /* | |
1115 | * Evict cached data | |
1116 | */ | |
1117 | if (dsl_dataset_is_dirty(dmu_objset_ds(zv->zv_objset)) && | |
1118 | !(zv->zv_flags & ZVOL_RDONLY)) | |
1119 | txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0); | |
1120 | (void) dmu_objset_evict_dbufs(zv->zv_objset); | |
040dab99 CC |
1121 | } |
1122 | ||
1123 | /* | |
1124 | * return the proper tag for rollback and recv | |
1125 | */ | |
1126 | void * | |
1127 | zvol_tag(zvol_state_t *zv) | |
1128 | { | |
1129 | ASSERT(RW_WRITE_HELD(&zv->zv_suspend_lock)); | |
1130 | return (zv->zv_open_count > 0 ? zv : NULL); | |
1131 | } | |
1132 | ||
1133 | /* | |
1134 | * Suspend the zvol for recv and rollback. | |
1135 | */ | |
1136 | zvol_state_t * | |
1137 | zvol_suspend(const char *name) | |
1138 | { | |
1139 | zvol_state_t *zv; | |
1140 | ||
1141 | mutex_enter(&zvol_state_lock); | |
1142 | zv = zvol_find_by_name(name); | |
5559ba09 BP |
1143 | if (zv == NULL) { |
1144 | mutex_exit(&zvol_state_lock); | |
1145 | return (NULL); | |
1146 | } | |
1147 | mutex_enter(&zv->zv_state_lock); | |
1148 | mutex_exit(&zvol_state_lock); | |
04434775 | 1149 | |
040dab99 CC |
1150 | /* block all I/O, release in zvol_resume. */ |
1151 | rw_enter(&zv->zv_suspend_lock, RW_WRITER); | |
1152 | ||
1153 | atomic_inc(&zv->zv_suspend_ref); | |
1154 | ||
1155 | if (zv->zv_open_count > 0) | |
1156 | zvol_shutdown_zv(zv); | |
5559ba09 BP |
1157 | |
1158 | mutex_exit(&zv->zv_state_lock); | |
040dab99 CC |
1159 | return (zv); |
1160 | } | |
1161 | ||
1162 | int | |
1163 | zvol_resume(zvol_state_t *zv) | |
1164 | { | |
1165 | int error = 0; | |
1166 | ||
1167 | ASSERT(RW_WRITE_HELD(&zv->zv_suspend_lock)); | |
2d82116e BP |
1168 | |
1169 | /* | |
1170 | * Cannot take zv_state_lock here with zv_suspend_lock | |
1171 | * held; however, the latter is held in exclusive mode, | |
1172 | * so it is not necessary to do so | |
1173 | */ | |
040dab99 CC |
1174 | if (zv->zv_open_count > 0) { |
1175 | VERIFY0(dmu_objset_hold(zv->zv_name, zv, &zv->zv_objset)); | |
1176 | VERIFY3P(zv->zv_objset->os_dsl_dataset->ds_owner, ==, zv); | |
1177 | VERIFY(dsl_dataset_long_held(zv->zv_objset->os_dsl_dataset)); | |
1178 | dmu_objset_rele(zv->zv_objset, zv); | |
1179 | ||
1180 | error = zvol_setup_zv(zv); | |
1181 | } | |
1182 | rw_exit(&zv->zv_suspend_lock); | |
1183 | /* | |
1184 | * We need this because we don't hold zvol_state_lock while releasing | |
1185 | * zv_suspend_lock. zvol_remove_minors_impl thus cannot check | |
1186 | * zv_suspend_lock to determine it is safe to free because rwlock is | |
1187 | * not inherent atomic. | |
1188 | */ | |
1189 | atomic_dec(&zv->zv_suspend_ref); | |
1190 | ||
1191 | return (SET_ERROR(error)); | |
1192 | } | |
1193 | ||
1194 | static int | |
1195 | zvol_first_open(zvol_state_t *zv) | |
1196 | { | |
1197 | objset_t *os; | |
07783588 BP |
1198 | int error, locked = 0; |
1199 | ||
1200 | /* | |
1201 | * In all other cases the spa_namespace_lock is taken before the | |
1202 | * bdev->bd_mutex lock. But in this case the Linux __blkdev_get() | |
1203 | * function calls fops->open() with the bdev->bd_mutex lock held. | |
1204 | * This deadlock can be easily observed with zvols used as vdevs. | |
1205 | * | |
1206 | * To avoid a potential lock inversion deadlock we preemptively | |
1207 | * try to take the spa_namespace_lock(). Normally it will not | |
1208 | * be contended and this is safe because spa_open_common() handles | |
1209 | * the case where the caller already holds the spa_namespace_lock. | |
1210 | * | |
1211 | * When it is contended we risk a lock inversion if we were to | |
1212 | * block waiting for the lock. Luckily, the __blkdev_get() | |
1213 | * function allows us to return -ERESTARTSYS which will result in | |
1214 | * bdev->bd_mutex being dropped, reacquired, and fops->open() being | |
1215 | * called again. This process can be repeated safely until both | |
1216 | * locks are acquired. | |
1217 | */ | |
1218 | if (!mutex_owned(&spa_namespace_lock)) { | |
1219 | locked = mutex_tryenter(&spa_namespace_lock); | |
1220 | if (!locked) | |
1221 | return (-SET_ERROR(ERESTARTSYS)); | |
1222 | } | |
040dab99 CC |
1223 | |
1224 | /* lie and say we're read-only */ | |
1225 | error = dmu_objset_own(zv->zv_name, DMU_OST_ZVOL, 1, zv, &os); | |
1226 | if (error) | |
07783588 | 1227 | goto out_mutex; |
040dab99 CC |
1228 | |
1229 | zv->zv_objset = os; | |
1230 | ||
1231 | error = zvol_setup_zv(zv); | |
1232 | ||
1233 | if (error) { | |
1234 | dmu_objset_disown(os, zv); | |
1235 | zv->zv_objset = NULL; | |
1236 | } | |
1237 | ||
07783588 BP |
1238 | out_mutex: |
1239 | if (locked) | |
1240 | mutex_exit(&spa_namespace_lock); | |
040dab99 CC |
1241 | return (SET_ERROR(-error)); |
1242 | } | |
1243 | ||
1244 | static void | |
1245 | zvol_last_close(zvol_state_t *zv) | |
1246 | { | |
1247 | zvol_shutdown_zv(zv); | |
1248 | ||
1249 | dmu_objset_disown(zv->zv_objset, zv); | |
60101509 BB |
1250 | zv->zv_objset = NULL; |
1251 | } | |
1252 | ||
1253 | static int | |
1254 | zvol_open(struct block_device *bdev, fmode_t flag) | |
1255 | { | |
5428dc51 | 1256 | zvol_state_t *zv; |
5559ba09 | 1257 | int error = 0, drop_suspend = 0; |
60101509 | 1258 | |
5559ba09 | 1259 | ASSERT(!mutex_owned(&zvol_state_lock)); |
60101509 | 1260 | |
5559ba09 | 1261 | mutex_enter(&zvol_state_lock); |
5428dc51 BP |
1262 | /* |
1263 | * Obtain a copy of private_data under the lock to make sure | |
5559ba09 | 1264 | * that either the result of zvol free code path setting |
5428dc51 BP |
1265 | * bdev->bd_disk->private_data to NULL is observed, or zvol_free() |
1266 | * is not called on this zv because of the positive zv_open_count. | |
1267 | */ | |
1268 | zv = bdev->bd_disk->private_data; | |
1269 | if (zv == NULL) { | |
5559ba09 BP |
1270 | mutex_exit(&zvol_state_lock); |
1271 | return (SET_ERROR(-ENXIO)); | |
5428dc51 | 1272 | } |
5559ba09 BP |
1273 | mutex_enter(&zv->zv_state_lock); |
1274 | mutex_exit(&zvol_state_lock); | |
60101509 BB |
1275 | |
1276 | if (zv->zv_open_count == 0) { | |
040dab99 CC |
1277 | /* make sure zvol is not suspended when first open */ |
1278 | rw_enter(&zv->zv_suspend_lock, RW_READER); | |
1279 | drop_suspend = 1; | |
1280 | ||
60101509 BB |
1281 | error = zvol_first_open(zv); |
1282 | if (error) | |
1283 | goto out_mutex; | |
1284 | } | |
1285 | ||
ba6a2402 | 1286 | if ((flag & FMODE_WRITE) && (zv->zv_flags & ZVOL_RDONLY)) { |
60101509 BB |
1287 | error = -EROFS; |
1288 | goto out_open_count; | |
1289 | } | |
1290 | ||
1291 | zv->zv_open_count++; | |
1292 | ||
5428dc51 BP |
1293 | check_disk_change(bdev); |
1294 | ||
60101509 BB |
1295 | out_open_count: |
1296 | if (zv->zv_open_count == 0) | |
1297 | zvol_last_close(zv); | |
60101509 | 1298 | out_mutex: |
040dab99 CC |
1299 | if (drop_suspend) |
1300 | rw_exit(&zv->zv_suspend_lock); | |
5559ba09 | 1301 | mutex_exit(&zv->zv_state_lock); |
60101509 | 1302 | |
ce37ebd2 | 1303 | return (SET_ERROR(error)); |
60101509 BB |
1304 | } |
1305 | ||
a1d9543a CD |
1306 | #ifdef HAVE_BLOCK_DEVICE_OPERATIONS_RELEASE_VOID |
1307 | static void | |
1308 | #else | |
60101509 | 1309 | static int |
a1d9543a | 1310 | #endif |
60101509 BB |
1311 | zvol_release(struct gendisk *disk, fmode_t mode) |
1312 | { | |
5559ba09 | 1313 | zvol_state_t *zv; |
60101509 | 1314 | |
5559ba09 | 1315 | ASSERT(!mutex_owned(&zvol_state_lock)); |
5428dc51 | 1316 | |
5559ba09 BP |
1317 | mutex_enter(&zvol_state_lock); |
1318 | zv = disk->private_data; | |
1319 | ASSERT(zv && zv->zv_open_count > 0); | |
1320 | mutex_enter(&zv->zv_state_lock); | |
1321 | mutex_exit(&zvol_state_lock); | |
60101509 | 1322 | |
040dab99 CC |
1323 | /* make sure zvol is not suspended when last close */ |
1324 | if (zv->zv_open_count == 1) | |
1325 | rw_enter(&zv->zv_suspend_lock, RW_READER); | |
1326 | ||
5428dc51 | 1327 | zv->zv_open_count--; |
040dab99 | 1328 | if (zv->zv_open_count == 0) { |
5428dc51 | 1329 | zvol_last_close(zv); |
040dab99 CC |
1330 | rw_exit(&zv->zv_suspend_lock); |
1331 | } | |
60101509 | 1332 | |
5559ba09 | 1333 | mutex_exit(&zv->zv_state_lock); |
60101509 | 1334 | |
a1d9543a | 1335 | #ifndef HAVE_BLOCK_DEVICE_OPERATIONS_RELEASE_VOID |
60101509 | 1336 | return (0); |
a1d9543a | 1337 | #endif |
60101509 BB |
1338 | } |
1339 | ||
1340 | static int | |
1341 | zvol_ioctl(struct block_device *bdev, fmode_t mode, | |
ce37ebd2 | 1342 | unsigned int cmd, unsigned long arg) |
60101509 BB |
1343 | { |
1344 | zvol_state_t *zv = bdev->bd_disk->private_data; | |
1345 | int error = 0; | |
1346 | ||
5428dc51 | 1347 | ASSERT(zv && zv->zv_open_count > 0); |
60101509 BB |
1348 | |
1349 | switch (cmd) { | |
1350 | case BLKFLSBUF: | |
ef1bdf36 BB |
1351 | fsync_bdev(bdev); |
1352 | invalidate_bdev(bdev); | |
1353 | rw_enter(&zv->zv_suspend_lock, RW_READER); | |
1354 | ||
1355 | if (dsl_dataset_is_dirty(dmu_objset_ds(zv->zv_objset)) && | |
1356 | !(zv->zv_flags & ZVOL_RDONLY)) | |
1357 | txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0); | |
1358 | ||
1359 | rw_exit(&zv->zv_suspend_lock); | |
60101509 | 1360 | break; |
ef1bdf36 | 1361 | |
4c0d8e50 | 1362 | case BLKZNAME: |
5559ba09 | 1363 | mutex_enter(&zv->zv_state_lock); |
4c0d8e50 | 1364 | error = copy_to_user((void *)arg, zv->zv_name, MAXNAMELEN); |
5559ba09 | 1365 | mutex_exit(&zv->zv_state_lock); |
4c0d8e50 | 1366 | break; |
60101509 BB |
1367 | |
1368 | default: | |
1369 | error = -ENOTTY; | |
1370 | break; | |
60101509 BB |
1371 | } |
1372 | ||
ce37ebd2 | 1373 | return (SET_ERROR(error)); |
60101509 BB |
1374 | } |
1375 | ||
1376 | #ifdef CONFIG_COMPAT | |
1377 | static int | |
1378 | zvol_compat_ioctl(struct block_device *bdev, fmode_t mode, | |
ce37ebd2 | 1379 | unsigned cmd, unsigned long arg) |
60101509 | 1380 | { |
ce37ebd2 | 1381 | return (zvol_ioctl(bdev, mode, cmd, arg)); |
60101509 BB |
1382 | } |
1383 | #else | |
ce37ebd2 | 1384 | #define zvol_compat_ioctl NULL |
60101509 BB |
1385 | #endif |
1386 | ||
1387 | static int zvol_media_changed(struct gendisk *disk) | |
1388 | { | |
1389 | zvol_state_t *zv = disk->private_data; | |
1390 | ||
5428dc51 BP |
1391 | ASSERT(zv && zv->zv_open_count > 0); |
1392 | ||
ce37ebd2 | 1393 | return (zv->zv_changed); |
60101509 BB |
1394 | } |
1395 | ||
1396 | static int zvol_revalidate_disk(struct gendisk *disk) | |
1397 | { | |
1398 | zvol_state_t *zv = disk->private_data; | |
1399 | ||
5428dc51 BP |
1400 | ASSERT(zv && zv->zv_open_count > 0); |
1401 | ||
60101509 BB |
1402 | zv->zv_changed = 0; |
1403 | set_capacity(zv->zv_disk, zv->zv_volsize >> 9); | |
1404 | ||
ce37ebd2 | 1405 | return (0); |
60101509 BB |
1406 | } |
1407 | ||
1408 | /* | |
1409 | * Provide a simple virtual geometry for legacy compatibility. For devices | |
1410 | * smaller than 1 MiB a small head and sector count is used to allow very | |
1411 | * tiny devices. For devices over 1 Mib a standard head and sector count | |
1412 | * is used to keep the cylinders count reasonable. | |
1413 | */ | |
1414 | static int | |
1415 | zvol_getgeo(struct block_device *bdev, struct hd_geometry *geo) | |
1416 | { | |
1417 | zvol_state_t *zv = bdev->bd_disk->private_data; | |
5428dc51 BP |
1418 | sector_t sectors; |
1419 | ||
1420 | ASSERT(zv && zv->zv_open_count > 0); | |
1421 | ||
1422 | sectors = get_capacity(zv->zv_disk); | |
60101509 BB |
1423 | |
1424 | if (sectors > 2048) { | |
1425 | geo->heads = 16; | |
1426 | geo->sectors = 63; | |
1427 | } else { | |
1428 | geo->heads = 2; | |
1429 | geo->sectors = 4; | |
1430 | } | |
1431 | ||
1432 | geo->start = 0; | |
1433 | geo->cylinders = sectors / (geo->heads * geo->sectors); | |
1434 | ||
ce37ebd2 | 1435 | return (0); |
60101509 BB |
1436 | } |
1437 | ||
1438 | static struct kobject * | |
1439 | zvol_probe(dev_t dev, int *part, void *arg) | |
1440 | { | |
1441 | zvol_state_t *zv; | |
1442 | struct kobject *kobj; | |
1443 | ||
1444 | mutex_enter(&zvol_state_lock); | |
1445 | zv = zvol_find_by_dev(dev); | |
23a61ccc | 1446 | kobj = zv ? get_disk(zv->zv_disk) : NULL; |
60101509 BB |
1447 | mutex_exit(&zvol_state_lock); |
1448 | ||
ce37ebd2 | 1449 | return (kobj); |
60101509 BB |
1450 | } |
1451 | ||
1452 | #ifdef HAVE_BDEV_BLOCK_DEVICE_OPERATIONS | |
1453 | static struct block_device_operations zvol_ops = { | |
ce37ebd2 BB |
1454 | .open = zvol_open, |
1455 | .release = zvol_release, | |
1456 | .ioctl = zvol_ioctl, | |
1457 | .compat_ioctl = zvol_compat_ioctl, | |
1458 | .media_changed = zvol_media_changed, | |
1459 | .revalidate_disk = zvol_revalidate_disk, | |
1460 | .getgeo = zvol_getgeo, | |
1461 | .owner = THIS_MODULE, | |
60101509 BB |
1462 | }; |
1463 | ||
1464 | #else /* HAVE_BDEV_BLOCK_DEVICE_OPERATIONS */ | |
1465 | ||
1466 | static int | |
1467 | zvol_open_by_inode(struct inode *inode, struct file *file) | |
1468 | { | |
ce37ebd2 | 1469 | return (zvol_open(inode->i_bdev, file->f_mode)); |
60101509 BB |
1470 | } |
1471 | ||
1472 | static int | |
1473 | zvol_release_by_inode(struct inode *inode, struct file *file) | |
1474 | { | |
ce37ebd2 | 1475 | return (zvol_release(inode->i_bdev->bd_disk, file->f_mode)); |
60101509 BB |
1476 | } |
1477 | ||
1478 | static int | |
1479 | zvol_ioctl_by_inode(struct inode *inode, struct file *file, | |
ce37ebd2 | 1480 | unsigned int cmd, unsigned long arg) |
60101509 | 1481 | { |
b1c58213 | 1482 | if (file == NULL || inode == NULL) |
ce37ebd2 BB |
1483 | return (SET_ERROR(-EINVAL)); |
1484 | ||
1485 | return (zvol_ioctl(inode->i_bdev, file->f_mode, cmd, arg)); | |
60101509 BB |
1486 | } |
1487 | ||
ce37ebd2 | 1488 | #ifdef CONFIG_COMPAT |
60101509 BB |
1489 | static long |
1490 | zvol_compat_ioctl_by_inode(struct file *file, | |
ce37ebd2 | 1491 | unsigned int cmd, unsigned long arg) |
60101509 | 1492 | { |
b1c58213 | 1493 | if (file == NULL) |
ce37ebd2 BB |
1494 | return (SET_ERROR(-EINVAL)); |
1495 | ||
1496 | return (zvol_compat_ioctl(file->f_dentry->d_inode->i_bdev, | |
1497 | file->f_mode, cmd, arg)); | |
60101509 | 1498 | } |
ce37ebd2 BB |
1499 | #else |
1500 | #define zvol_compat_ioctl_by_inode NULL | |
1501 | #endif | |
60101509 BB |
1502 | |
1503 | static struct block_device_operations zvol_ops = { | |
ce37ebd2 BB |
1504 | .open = zvol_open_by_inode, |
1505 | .release = zvol_release_by_inode, | |
1506 | .ioctl = zvol_ioctl_by_inode, | |
1507 | .compat_ioctl = zvol_compat_ioctl_by_inode, | |
1508 | .media_changed = zvol_media_changed, | |
1509 | .revalidate_disk = zvol_revalidate_disk, | |
1510 | .getgeo = zvol_getgeo, | |
1511 | .owner = THIS_MODULE, | |
60101509 BB |
1512 | }; |
1513 | #endif /* HAVE_BDEV_BLOCK_DEVICE_OPERATIONS */ | |
1514 | ||
1515 | /* | |
1516 | * Allocate memory for a new zvol_state_t and setup the required | |
1517 | * request queue and generic disk structures for the block device. | |
1518 | */ | |
1519 | static zvol_state_t * | |
1520 | zvol_alloc(dev_t dev, const char *name) | |
1521 | { | |
1522 | zvol_state_t *zv; | |
1523 | ||
79c76d5b | 1524 | zv = kmem_zalloc(sizeof (zvol_state_t), KM_SLEEP); |
60101509 | 1525 | |
2a3871d4 RY |
1526 | list_link_init(&zv->zv_next); |
1527 | ||
5559ba09 BP |
1528 | mutex_init(&zv->zv_state_lock, NULL, MUTEX_DEFAULT, NULL); |
1529 | ||
37f9dac5 | 1530 | zv->zv_queue = blk_alloc_queue(GFP_ATOMIC); |
60101509 BB |
1531 | if (zv->zv_queue == NULL) |
1532 | goto out_kmem; | |
1533 | ||
37f9dac5 | 1534 | blk_queue_make_request(zv->zv_queue, zvol_request); |
cf41432c | 1535 | blk_queue_set_write_cache(zv->zv_queue, B_TRUE, B_TRUE); |
b18019d2 | 1536 | |
bc17f104 RY |
1537 | /* Limit read-ahead to a single page to prevent over-prefetching. */ |
1538 | blk_queue_set_read_ahead(zv->zv_queue, 1); | |
1539 | ||
5731140e R |
1540 | /* Disable write merging in favor of the ZIO pipeline. */ |
1541 | queue_flag_set(QUEUE_FLAG_NOMERGES, zv->zv_queue); | |
1542 | ||
60101509 BB |
1543 | zv->zv_disk = alloc_disk(ZVOL_MINORS); |
1544 | if (zv->zv_disk == NULL) | |
1545 | goto out_queue; | |
1546 | ||
1547 | zv->zv_queue->queuedata = zv; | |
1548 | zv->zv_dev = dev; | |
1549 | zv->zv_open_count = 0; | |
4c0d8e50 | 1550 | strlcpy(zv->zv_name, name, MAXNAMELEN); |
60101509 | 1551 | |
d88895a0 | 1552 | zfs_rlock_init(&zv->zv_range_lock); |
040dab99 | 1553 | rw_init(&zv->zv_suspend_lock, NULL, RW_DEFAULT, NULL); |
3c4988c8 | 1554 | |
60101509 BB |
1555 | zv->zv_disk->major = zvol_major; |
1556 | zv->zv_disk->first_minor = (dev & MINORMASK); | |
1557 | zv->zv_disk->fops = &zvol_ops; | |
1558 | zv->zv_disk->private_data = zv; | |
1559 | zv->zv_disk->queue = zv->zv_queue; | |
4c0d8e50 FN |
1560 | snprintf(zv->zv_disk->disk_name, DISK_NAME_LEN, "%s%d", |
1561 | ZVOL_DEV_NAME, (dev & MINORMASK)); | |
60101509 | 1562 | |
ce37ebd2 | 1563 | return (zv); |
60101509 BB |
1564 | |
1565 | out_queue: | |
1566 | blk_cleanup_queue(zv->zv_queue); | |
1567 | out_kmem: | |
1568 | kmem_free(zv, sizeof (zvol_state_t)); | |
0a6bef26 | 1569 | |
ce37ebd2 | 1570 | return (NULL); |
60101509 BB |
1571 | } |
1572 | ||
1573 | /* | |
5559ba09 BP |
1574 | * Cleanup then free a zvol_state_t which was created by zvol_alloc(). |
1575 | * At this time, the structure is not opened by anyone, is taken off | |
1576 | * the zvol_state_list, and has its private data set to NULL. | |
1577 | * The zvol_state_lock is dropped. | |
60101509 BB |
1578 | */ |
1579 | static void | |
5559ba09 | 1580 | zvol_free(void *arg) |
60101509 | 1581 | { |
899662e3 | 1582 | zvol_state_t *zv = arg; |
5559ba09 BP |
1583 | |
1584 | ASSERT(!MUTEX_HELD(&zvol_state_lock)); | |
5428dc51 | 1585 | ASSERT(zv->zv_open_count == 0); |
5559ba09 | 1586 | ASSERT(zv->zv_disk->private_data == NULL); |
5428dc51 | 1587 | |
040dab99 | 1588 | rw_destroy(&zv->zv_suspend_lock); |
d88895a0 | 1589 | zfs_rlock_destroy(&zv->zv_range_lock); |
60101509 BB |
1590 | |
1591 | del_gendisk(zv->zv_disk); | |
1592 | blk_cleanup_queue(zv->zv_queue); | |
1593 | put_disk(zv->zv_disk); | |
1594 | ||
d45e010d | 1595 | ida_simple_remove(&zvol_ida, MINOR(zv->zv_dev) >> ZVOL_MINOR_BITS); |
60101509 | 1596 | |
5559ba09 BP |
1597 | mutex_destroy(&zv->zv_state_lock); |
1598 | ||
1599 | kmem_free(zv, sizeof (zvol_state_t)); | |
899662e3 CC |
1600 | } |
1601 | ||
a0bd735a BP |
1602 | /* |
1603 | * Create a block device minor node and setup the linkage between it | |
1604 | * and the specified volume. Once this function returns the block | |
1605 | * device is live and ready for use. | |
1606 | */ | |
60101509 | 1607 | static int |
a0bd735a | 1608 | zvol_create_minor_impl(const char *name) |
60101509 BB |
1609 | { |
1610 | zvol_state_t *zv; | |
1611 | objset_t *os; | |
1612 | dmu_object_info_t *doi; | |
1613 | uint64_t volsize; | |
9965059a | 1614 | uint64_t len; |
60101509 BB |
1615 | unsigned minor = 0; |
1616 | int error = 0; | |
d45e010d CC |
1617 | int idx; |
1618 | uint64_t hash = zvol_name_hash(name); | |
1619 | ||
1620 | idx = ida_simple_get(&zvol_ida, 0, 0, kmem_flags_convert(KM_SLEEP)); | |
1621 | if (idx < 0) | |
1622 | return (SET_ERROR(-idx)); | |
1623 | minor = idx << ZVOL_MINOR_BITS; | |
60101509 | 1624 | |
a0bd735a | 1625 | mutex_enter(&zvol_state_lock); |
60101509 | 1626 | |
d45e010d | 1627 | zv = zvol_find_by_name_hash(name, hash); |
60101509 | 1628 | if (zv) { |
5559ba09 | 1629 | mutex_exit(&zvol_state_lock); |
2d82116e | 1630 | ida_simple_remove(&zvol_ida, idx); |
5559ba09 | 1631 | return (SET_ERROR(EEXIST)); |
60101509 BB |
1632 | } |
1633 | ||
5559ba09 BP |
1634 | mutex_exit(&zvol_state_lock); |
1635 | ||
79c76d5b | 1636 | doi = kmem_alloc(sizeof (dmu_object_info_t), KM_SLEEP); |
60101509 | 1637 | |
040dab99 | 1638 | error = dmu_objset_own(name, DMU_OST_ZVOL, B_TRUE, FTAG, &os); |
60101509 BB |
1639 | if (error) |
1640 | goto out_doi; | |
1641 | ||
1642 | error = dmu_object_info(os, ZVOL_OBJ, doi); | |
1643 | if (error) | |
1644 | goto out_dmu_objset_disown; | |
1645 | ||
1646 | error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize); | |
1647 | if (error) | |
1648 | goto out_dmu_objset_disown; | |
1649 | ||
60101509 BB |
1650 | zv = zvol_alloc(MKDEV(zvol_major, minor), name); |
1651 | if (zv == NULL) { | |
2e528b49 | 1652 | error = SET_ERROR(EAGAIN); |
60101509 BB |
1653 | goto out_dmu_objset_disown; |
1654 | } | |
d45e010d | 1655 | zv->zv_hash = hash; |
60101509 BB |
1656 | |
1657 | if (dmu_objset_is_snapshot(os)) | |
1658 | zv->zv_flags |= ZVOL_RDONLY; | |
1659 | ||
1660 | zv->zv_volblocksize = doi->doi_data_block_size; | |
1661 | zv->zv_volsize = volsize; | |
1662 | zv->zv_objset = os; | |
1663 | ||
1664 | set_capacity(zv->zv_disk, zv->zv_volsize >> 9); | |
1665 | ||
c495fe2c | 1666 | blk_queue_max_hw_sectors(zv->zv_queue, (DMU_MAX_ACCESS / 4) >> 9); |
34037afe ED |
1667 | blk_queue_max_segments(zv->zv_queue, UINT16_MAX); |
1668 | blk_queue_max_segment_size(zv->zv_queue, UINT_MAX); | |
1669 | blk_queue_physical_block_size(zv->zv_queue, zv->zv_volblocksize); | |
1670 | blk_queue_io_opt(zv->zv_queue, zv->zv_volblocksize); | |
7c0e5708 ED |
1671 | blk_queue_max_discard_sectors(zv->zv_queue, |
1672 | (zvol_max_discard_blocks * zv->zv_volblocksize) >> 9); | |
ee5fd0bb | 1673 | blk_queue_discard_granularity(zv->zv_queue, zv->zv_volblocksize); |
30930fba | 1674 | queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, zv->zv_queue); |
37f9dac5 | 1675 | #ifdef QUEUE_FLAG_NONROT |
34037afe ED |
1676 | queue_flag_set_unlocked(QUEUE_FLAG_NONROT, zv->zv_queue); |
1677 | #endif | |
c6a3a222 RY |
1678 | #ifdef QUEUE_FLAG_ADD_RANDOM |
1679 | queue_flag_clear_unlocked(QUEUE_FLAG_ADD_RANDOM, zv->zv_queue); | |
1680 | #endif | |
34037afe | 1681 | |
a4430fce GW |
1682 | if (spa_writeable(dmu_objset_spa(os))) { |
1683 | if (zil_replay_disable) | |
1684 | zil_destroy(dmu_objset_zil(os), B_FALSE); | |
1685 | else | |
1686 | zil_replay(os, zv, zvol_replay_vector); | |
1687 | } | |
60101509 | 1688 | |
9965059a BB |
1689 | /* |
1690 | * When udev detects the addition of the device it will immediately | |
1691 | * invoke blkid(8) to determine the type of content on the device. | |
1692 | * Prefetching the blocks commonly scanned by blkid(8) will speed | |
1693 | * up this process. | |
1694 | */ | |
1695 | len = MIN(MAX(zvol_prefetch_bytes, 0), SPA_MAXBLOCKSIZE); | |
1696 | if (len > 0) { | |
fcff0f35 PD |
1697 | dmu_prefetch(os, ZVOL_OBJ, 0, 0, len, ZIO_PRIORITY_SYNC_READ); |
1698 | dmu_prefetch(os, ZVOL_OBJ, 0, volsize - len, len, | |
02730c33 | 1699 | ZIO_PRIORITY_SYNC_READ); |
9965059a BB |
1700 | } |
1701 | ||
f74a147c | 1702 | zv->zv_objset = NULL; |
60101509 | 1703 | out_dmu_objset_disown: |
040dab99 | 1704 | dmu_objset_disown(os, FTAG); |
60101509 | 1705 | out_doi: |
ce37ebd2 | 1706 | kmem_free(doi, sizeof (dmu_object_info_t)); |
60101509 BB |
1707 | |
1708 | if (error == 0) { | |
5559ba09 | 1709 | mutex_enter(&zvol_state_lock); |
60101509 | 1710 | zvol_insert(zv); |
5428dc51 | 1711 | mutex_exit(&zvol_state_lock); |
60101509 | 1712 | add_disk(zv->zv_disk); |
a0bd735a | 1713 | } else { |
d45e010d | 1714 | ida_simple_remove(&zvol_ida, idx); |
60101509 BB |
1715 | } |
1716 | ||
ce37ebd2 | 1717 | return (SET_ERROR(error)); |
60101509 BB |
1718 | } |
1719 | ||
ba6a2402 BB |
1720 | /* |
1721 | * Rename a block device minor mode for the specified volume. | |
1722 | */ | |
1723 | static void | |
a0bd735a | 1724 | zvol_rename_minor(zvol_state_t *zv, const char *newname) |
ba6a2402 BB |
1725 | { |
1726 | int readonly = get_disk_ro(zv->zv_disk); | |
1727 | ||
1728 | ASSERT(MUTEX_HELD(&zvol_state_lock)); | |
1729 | ||
040dab99 | 1730 | rw_enter(&zv->zv_suspend_lock, RW_READER); |
ba6a2402 | 1731 | strlcpy(zv->zv_name, newname, sizeof (zv->zv_name)); |
040dab99 CC |
1732 | rw_exit(&zv->zv_suspend_lock); |
1733 | ||
1734 | /* move to new hashtable entry */ | |
1735 | zv->zv_hash = zvol_name_hash(zv->zv_name); | |
1736 | hlist_del(&zv->zv_hlink); | |
1737 | hlist_add_head(&zv->zv_hlink, ZVOL_HT_HEAD(zv->zv_hash)); | |
ba6a2402 BB |
1738 | |
1739 | /* | |
1740 | * The block device's read-only state is briefly changed causing | |
1741 | * a KOBJ_CHANGE uevent to be issued. This ensures udev detects | |
1742 | * the name change and fixes the symlinks. This does not change | |
1743 | * ZVOL_RDONLY in zv->zv_flags so the actual read-only state never | |
1744 | * changes. This would normally be done using kobject_uevent() but | |
1745 | * that is a GPL-only symbol which is why we need this workaround. | |
1746 | */ | |
1747 | set_disk_ro(zv->zv_disk, !readonly); | |
1748 | set_disk_ro(zv->zv_disk, readonly); | |
1749 | } | |
1750 | ||
7ac557ce CC |
1751 | typedef struct minors_job { |
1752 | list_t *list; | |
1753 | list_node_t link; | |
1754 | /* input */ | |
1755 | char *name; | |
1756 | /* output */ | |
1757 | int error; | |
1758 | } minors_job_t; | |
1759 | ||
1760 | /* | |
1761 | * Prefetch zvol dnodes for the minors_job | |
1762 | */ | |
1763 | static void | |
1764 | zvol_prefetch_minors_impl(void *arg) | |
1765 | { | |
1766 | minors_job_t *job = arg; | |
1767 | char *dsname = job->name; | |
1768 | objset_t *os = NULL; | |
1769 | ||
040dab99 | 1770 | job->error = dmu_objset_own(dsname, DMU_OST_ZVOL, B_TRUE, FTAG, |
7ac557ce CC |
1771 | &os); |
1772 | if (job->error == 0) { | |
1773 | dmu_prefetch(os, ZVOL_OBJ, 0, 0, 0, ZIO_PRIORITY_SYNC_READ); | |
040dab99 | 1774 | dmu_objset_disown(os, FTAG); |
7ac557ce CC |
1775 | } |
1776 | } | |
a0bd735a BP |
1777 | |
1778 | /* | |
1779 | * Mask errors to continue dmu_objset_find() traversal | |
1780 | */ | |
1781 | static int | |
1782 | zvol_create_snap_minor_cb(const char *dsname, void *arg) | |
1783 | { | |
7ac557ce CC |
1784 | minors_job_t *j = arg; |
1785 | list_t *minors_list = j->list; | |
1786 | const char *name = j->name; | |
a0bd735a | 1787 | |
1ee159f4 BP |
1788 | ASSERT0(MUTEX_HELD(&spa_namespace_lock)); |
1789 | ||
a0bd735a BP |
1790 | /* skip the designated dataset */ |
1791 | if (name && strcmp(dsname, name) == 0) | |
1792 | return (0); | |
1793 | ||
1794 | /* at this point, the dsname should name a snapshot */ | |
1795 | if (strchr(dsname, '@') == 0) { | |
1796 | dprintf("zvol_create_snap_minor_cb(): " | |
02730c33 | 1797 | "%s is not a shapshot name\n", dsname); |
a0bd735a | 1798 | } else { |
7ac557ce CC |
1799 | minors_job_t *job; |
1800 | char *n = strdup(dsname); | |
1801 | if (n == NULL) | |
1802 | return (0); | |
1803 | ||
1804 | job = kmem_alloc(sizeof (minors_job_t), KM_SLEEP); | |
1805 | job->name = n; | |
1806 | job->list = minors_list; | |
1807 | job->error = 0; | |
1808 | list_insert_tail(minors_list, job); | |
1809 | /* don't care if dispatch fails, because job->error is 0 */ | |
1810 | taskq_dispatch(system_taskq, zvol_prefetch_minors_impl, job, | |
1811 | TQ_SLEEP); | |
a0bd735a BP |
1812 | } |
1813 | ||
1814 | return (0); | |
1815 | } | |
1816 | ||
1817 | /* | |
1818 | * Mask errors to continue dmu_objset_find() traversal | |
1819 | */ | |
60101509 | 1820 | static int |
13fe0198 | 1821 | zvol_create_minors_cb(const char *dsname, void *arg) |
60101509 | 1822 | { |
a0bd735a BP |
1823 | uint64_t snapdev; |
1824 | int error; | |
7ac557ce | 1825 | list_t *minors_list = arg; |
a0bd735a | 1826 | |
1ee159f4 BP |
1827 | ASSERT0(MUTEX_HELD(&spa_namespace_lock)); |
1828 | ||
a0bd735a BP |
1829 | error = dsl_prop_get_integer(dsname, "snapdev", &snapdev, NULL); |
1830 | if (error) | |
1831 | return (0); | |
1832 | ||
1833 | /* | |
1834 | * Given the name and the 'snapdev' property, create device minor nodes | |
1835 | * with the linkages to zvols/snapshots as needed. | |
1836 | * If the name represents a zvol, create a minor node for the zvol, then | |
1837 | * check if its snapshots are 'visible', and if so, iterate over the | |
1838 | * snapshots and create device minor nodes for those. | |
1839 | */ | |
1840 | if (strchr(dsname, '@') == 0) { | |
7ac557ce CC |
1841 | minors_job_t *job; |
1842 | char *n = strdup(dsname); | |
1843 | if (n == NULL) | |
1844 | return (0); | |
1845 | ||
1846 | job = kmem_alloc(sizeof (minors_job_t), KM_SLEEP); | |
1847 | job->name = n; | |
1848 | job->list = minors_list; | |
1849 | job->error = 0; | |
1850 | list_insert_tail(minors_list, job); | |
1851 | /* don't care if dispatch fails, because job->error is 0 */ | |
1852 | taskq_dispatch(system_taskq, zvol_prefetch_minors_impl, job, | |
1853 | TQ_SLEEP); | |
1854 | ||
1855 | if (snapdev == ZFS_SNAPDEV_VISIBLE) { | |
a0bd735a BP |
1856 | /* |
1857 | * traverse snapshots only, do not traverse children, | |
1858 | * and skip the 'dsname' | |
1859 | */ | |
1860 | error = dmu_objset_find((char *)dsname, | |
7ac557ce | 1861 | zvol_create_snap_minor_cb, (void *)job, |
a0bd735a | 1862 | DS_FIND_SNAPSHOTS); |
a0bd735a BP |
1863 | } |
1864 | } else { | |
1865 | dprintf("zvol_create_minors_cb(): %s is not a zvol name\n", | |
02730c33 | 1866 | dsname); |
a0bd735a | 1867 | } |
60101509 | 1868 | |
d5674448 | 1869 | return (0); |
60101509 BB |
1870 | } |
1871 | ||
1872 | /* | |
a0bd735a BP |
1873 | * Create minors for the specified dataset, including children and snapshots. |
1874 | * Pay attention to the 'snapdev' property and iterate over the snapshots | |
1875 | * only if they are 'visible'. This approach allows one to assure that the | |
1876 | * snapshot metadata is read from disk only if it is needed. | |
1877 | * | |
1878 | * The name can represent a dataset to be recursively scanned for zvols and | |
1879 | * their snapshots, or a single zvol snapshot. If the name represents a | |
1880 | * dataset, the scan is performed in two nested stages: | |
1881 | * - scan the dataset for zvols, and | |
1882 | * - for each zvol, create a minor node, then check if the zvol's snapshots | |
1883 | * are 'visible', and only then iterate over the snapshots if needed | |
1884 | * | |
4e33ba4c | 1885 | * If the name represents a snapshot, a check is performed if the snapshot is |
a0bd735a BP |
1886 | * 'visible' (which also verifies that the parent is a zvol), and if so, |
1887 | * a minor node for that snapshot is created. | |
60101509 | 1888 | */ |
a0bd735a BP |
1889 | static int |
1890 | zvol_create_minors_impl(const char *name) | |
60101509 | 1891 | { |
60101509 | 1892 | int error = 0; |
5428dc51 | 1893 | fstrans_cookie_t cookie; |
a0bd735a | 1894 | char *atp, *parent; |
7ac557ce CC |
1895 | list_t minors_list; |
1896 | minors_job_t *job; | |
60101509 | 1897 | |
5428dc51 BP |
1898 | if (zvol_inhibit_dev) |
1899 | return (0); | |
1900 | ||
7ac557ce CC |
1901 | /* |
1902 | * This is the list for prefetch jobs. Whenever we found a match | |
1903 | * during dmu_objset_find, we insert a minors_job to the list and do | |
1904 | * taskq_dispatch to parallel prefetch zvol dnodes. Note we don't need | |
1905 | * any lock because all list operation is done on the current thread. | |
1906 | * | |
1907 | * We will use this list to do zvol_create_minor_impl after prefetch | |
1908 | * so we don't have to traverse using dmu_objset_find again. | |
1909 | */ | |
1910 | list_create(&minors_list, sizeof (minors_job_t), | |
1911 | offsetof(minors_job_t, link)); | |
1912 | ||
a0bd735a BP |
1913 | parent = kmem_alloc(MAXPATHLEN, KM_SLEEP); |
1914 | (void) strlcpy(parent, name, MAXPATHLEN); | |
1915 | ||
1916 | if ((atp = strrchr(parent, '@')) != NULL) { | |
1917 | uint64_t snapdev; | |
1918 | ||
1919 | *atp = '\0'; | |
1920 | error = dsl_prop_get_integer(parent, "snapdev", | |
1921 | &snapdev, NULL); | |
1922 | ||
1923 | if (error == 0 && snapdev == ZFS_SNAPDEV_VISIBLE) | |
1924 | error = zvol_create_minor_impl(name); | |
1925 | } else { | |
1926 | cookie = spl_fstrans_mark(); | |
1927 | error = dmu_objset_find(parent, zvol_create_minors_cb, | |
7ac557ce | 1928 | &minors_list, DS_FIND_CHILDREN); |
a0bd735a BP |
1929 | spl_fstrans_unmark(cookie); |
1930 | } | |
1931 | ||
1932 | kmem_free(parent, MAXPATHLEN); | |
7ac557ce CC |
1933 | taskq_wait_outstanding(system_taskq, 0); |
1934 | ||
1935 | /* | |
1936 | * Prefetch is completed, we can do zvol_create_minor_impl | |
1937 | * sequentially. | |
1938 | */ | |
1939 | while ((job = list_head(&minors_list)) != NULL) { | |
1940 | list_remove(&minors_list, job); | |
1941 | if (!job->error) | |
1942 | zvol_create_minor_impl(job->name); | |
1943 | strfree(job->name); | |
1944 | kmem_free(job, sizeof (minors_job_t)); | |
1945 | } | |
1946 | ||
1947 | list_destroy(&minors_list); | |
ba6a2402 BB |
1948 | |
1949 | return (SET_ERROR(error)); | |
1950 | } | |
1951 | ||
1952 | /* | |
1953 | * Remove minors for specified dataset including children and snapshots. | |
1954 | */ | |
a0bd735a BP |
1955 | static void |
1956 | zvol_remove_minors_impl(const char *name) | |
ba6a2402 BB |
1957 | { |
1958 | zvol_state_t *zv, *zv_next; | |
1959 | int namelen = ((name) ? strlen(name) : 0); | |
899662e3 | 1960 | taskqid_t t, tid = TASKQID_INVALID; |
5559ba09 | 1961 | list_t free_list; |
ba6a2402 | 1962 | |
74497b7a | 1963 | if (zvol_inhibit_dev) |
ba6a2402 | 1964 | return; |
74497b7a | 1965 | |
5559ba09 BP |
1966 | list_create(&free_list, sizeof (zvol_state_t), |
1967 | offsetof(zvol_state_t, zv_next)); | |
1968 | ||
60101509 | 1969 | mutex_enter(&zvol_state_lock); |
ba6a2402 BB |
1970 | |
1971 | for (zv = list_head(&zvol_state_list); zv != NULL; zv = zv_next) { | |
1972 | zv_next = list_next(&zvol_state_list, zv); | |
1973 | ||
1974 | if (name == NULL || strcmp(zv->zv_name, name) == 0 || | |
1975 | (strncmp(zv->zv_name, name, namelen) == 0 && | |
5428dc51 BP |
1976 | (zv->zv_name[namelen] == '/' || |
1977 | zv->zv_name[namelen] == '@'))) { | |
1978 | ||
1979 | /* If in use, leave alone */ | |
040dab99 CC |
1980 | if (zv->zv_open_count > 0 || |
1981 | atomic_read(&zv->zv_suspend_ref)) | |
5428dc51 | 1982 | continue; |
5559ba09 BP |
1983 | /* |
1984 | * By taking zv_state_lock here, we guarantee that no | |
1985 | * one is currently using this zv | |
1986 | */ | |
1987 | mutex_enter(&zv->zv_state_lock); | |
ba6a2402 | 1988 | zvol_remove(zv); |
5559ba09 | 1989 | mutex_exit(&zv->zv_state_lock); |
899662e3 CC |
1990 | |
1991 | /* clear this so zvol_open won't open it */ | |
1992 | zv->zv_disk->private_data = NULL; | |
1993 | ||
1994 | /* try parallel zv_free, if failed do it in place */ | |
5559ba09 | 1995 | t = taskq_dispatch(system_taskq, zvol_free, zv, |
899662e3 CC |
1996 | TQ_SLEEP); |
1997 | if (t == TASKQID_INVALID) | |
5559ba09 | 1998 | list_insert_head(&free_list, zv); |
899662e3 CC |
1999 | else |
2000 | tid = t; | |
60101509 | 2001 | } |
60101509 | 2002 | } |
ba6a2402 | 2003 | mutex_exit(&zvol_state_lock); |
5559ba09 BP |
2004 | |
2005 | /* | |
2006 | * Drop zvol_state_lock before calling zvol_free() | |
2007 | */ | |
2008 | while ((zv = list_head(&free_list)) != NULL) { | |
2009 | list_remove(&free_list, zv); | |
2010 | zvol_free(zv); | |
2011 | } | |
2012 | ||
899662e3 CC |
2013 | if (tid != TASKQID_INVALID) |
2014 | taskq_wait_outstanding(system_taskq, tid); | |
60101509 BB |
2015 | } |
2016 | ||
a0bd735a BP |
2017 | /* Remove minor for this specific snapshot only */ |
2018 | static void | |
2019 | zvol_remove_minor_impl(const char *name) | |
2020 | { | |
92aceb2a | 2021 | zvol_state_t *zv = NULL, *zv_next; |
a0bd735a BP |
2022 | |
2023 | if (zvol_inhibit_dev) | |
2024 | return; | |
2025 | ||
2026 | if (strchr(name, '@') == NULL) | |
2027 | return; | |
2028 | ||
2029 | mutex_enter(&zvol_state_lock); | |
2030 | ||
2031 | for (zv = list_head(&zvol_state_list); zv != NULL; zv = zv_next) { | |
2032 | zv_next = list_next(&zvol_state_list, zv); | |
2033 | ||
2034 | if (strcmp(zv->zv_name, name) == 0) { | |
2035 | /* If in use, leave alone */ | |
040dab99 CC |
2036 | if (zv->zv_open_count > 0 || |
2037 | atomic_read(&zv->zv_suspend_ref)) | |
a0bd735a | 2038 | continue; |
5559ba09 BP |
2039 | /* |
2040 | * By taking zv_state_lock here, we guarantee that no | |
2041 | * one is currently using this zv | |
2042 | */ | |
2043 | mutex_enter(&zv->zv_state_lock); | |
a0bd735a | 2044 | zvol_remove(zv); |
5559ba09 BP |
2045 | mutex_exit(&zv->zv_state_lock); |
2046 | /* clear this so zvol_open won't open it */ | |
2047 | zv->zv_disk->private_data = NULL; | |
a0bd735a BP |
2048 | break; |
2049 | } | |
2050 | } | |
2051 | ||
92aceb2a | 2052 | /* Drop zvol_state_lock before calling zvol_free() */ |
a0bd735a | 2053 | mutex_exit(&zvol_state_lock); |
5559ba09 | 2054 | |
92aceb2a | 2055 | if (zv != NULL) |
2056 | zvol_free(zv); | |
a0bd735a BP |
2057 | } |
2058 | ||
60101509 | 2059 | /* |
ba6a2402 | 2060 | * Rename minors for specified dataset including children and snapshots. |
60101509 | 2061 | */ |
a0bd735a BP |
2062 | static void |
2063 | zvol_rename_minors_impl(const char *oldname, const char *newname) | |
60101509 BB |
2064 | { |
2065 | zvol_state_t *zv, *zv_next; | |
ba6a2402 BB |
2066 | int oldnamelen, newnamelen; |
2067 | char *name; | |
60101509 | 2068 | |
74497b7a DH |
2069 | if (zvol_inhibit_dev) |
2070 | return; | |
2071 | ||
ba6a2402 BB |
2072 | oldnamelen = strlen(oldname); |
2073 | newnamelen = strlen(newname); | |
79c76d5b | 2074 | name = kmem_alloc(MAXNAMELEN, KM_SLEEP); |
60101509 BB |
2075 | |
2076 | mutex_enter(&zvol_state_lock); | |
ba6a2402 | 2077 | |
60101509 BB |
2078 | for (zv = list_head(&zvol_state_list); zv != NULL; zv = zv_next) { |
2079 | zv_next = list_next(&zvol_state_list, zv); | |
2080 | ||
5428dc51 BP |
2081 | /* If in use, leave alone */ |
2082 | if (zv->zv_open_count > 0) | |
2083 | continue; | |
2084 | ||
ba6a2402 | 2085 | if (strcmp(zv->zv_name, oldname) == 0) { |
a0bd735a | 2086 | zvol_rename_minor(zv, newname); |
ba6a2402 BB |
2087 | } else if (strncmp(zv->zv_name, oldname, oldnamelen) == 0 && |
2088 | (zv->zv_name[oldnamelen] == '/' || | |
2089 | zv->zv_name[oldnamelen] == '@')) { | |
2090 | snprintf(name, MAXNAMELEN, "%s%c%s", newname, | |
2091 | zv->zv_name[oldnamelen], | |
2092 | zv->zv_name + oldnamelen + 1); | |
a0bd735a | 2093 | zvol_rename_minor(zv, name); |
60101509 BB |
2094 | } |
2095 | } | |
ba6a2402 | 2096 | |
60101509 | 2097 | mutex_exit(&zvol_state_lock); |
ba6a2402 BB |
2098 | |
2099 | kmem_free(name, MAXNAMELEN); | |
60101509 BB |
2100 | } |
2101 | ||
a0bd735a BP |
2102 | typedef struct zvol_snapdev_cb_arg { |
2103 | uint64_t snapdev; | |
2104 | } zvol_snapdev_cb_arg_t; | |
2105 | ||
0b4d1b58 | 2106 | static int |
4ea3f864 GM |
2107 | zvol_set_snapdev_cb(const char *dsname, void *param) |
2108 | { | |
a0bd735a | 2109 | zvol_snapdev_cb_arg_t *arg = param; |
0b4d1b58 ED |
2110 | |
2111 | if (strchr(dsname, '@') == NULL) | |
ba6a2402 | 2112 | return (0); |
0b4d1b58 | 2113 | |
a0bd735a | 2114 | switch (arg->snapdev) { |
0b4d1b58 | 2115 | case ZFS_SNAPDEV_VISIBLE: |
a0bd735a | 2116 | (void) zvol_create_minor_impl(dsname); |
0b4d1b58 ED |
2117 | break; |
2118 | case ZFS_SNAPDEV_HIDDEN: | |
a0bd735a | 2119 | (void) zvol_remove_minor_impl(dsname); |
0b4d1b58 ED |
2120 | break; |
2121 | } | |
ba6a2402 BB |
2122 | |
2123 | return (0); | |
0b4d1b58 ED |
2124 | } |
2125 | ||
a0bd735a BP |
2126 | static void |
2127 | zvol_set_snapdev_impl(char *name, uint64_t snapdev) | |
2128 | { | |
2129 | zvol_snapdev_cb_arg_t arg = {snapdev}; | |
2130 | fstrans_cookie_t cookie = spl_fstrans_mark(); | |
2131 | /* | |
2132 | * The zvol_set_snapdev_sync() sets snapdev appropriately | |
2133 | * in the dataset hierarchy. Here, we only scan snapshots. | |
2134 | */ | |
2135 | dmu_objset_find(name, zvol_set_snapdev_cb, &arg, DS_FIND_SNAPSHOTS); | |
2136 | spl_fstrans_unmark(cookie); | |
2137 | } | |
2138 | ||
2139 | static zvol_task_t * | |
2140 | zvol_task_alloc(zvol_async_op_t op, const char *name1, const char *name2, | |
2141 | uint64_t snapdev) | |
2142 | { | |
2143 | zvol_task_t *task; | |
2144 | char *delim; | |
2145 | ||
2146 | /* Never allow tasks on hidden names. */ | |
2147 | if (name1[0] == '$') | |
2148 | return (NULL); | |
2149 | ||
2150 | task = kmem_zalloc(sizeof (zvol_task_t), KM_SLEEP); | |
2151 | task->op = op; | |
2152 | task->snapdev = snapdev; | |
2153 | delim = strchr(name1, '/'); | |
2154 | strlcpy(task->pool, name1, delim ? (delim - name1 + 1) : MAXNAMELEN); | |
2155 | ||
2156 | strlcpy(task->name1, name1, MAXNAMELEN); | |
2157 | if (name2 != NULL) | |
2158 | strlcpy(task->name2, name2, MAXNAMELEN); | |
2159 | ||
2160 | return (task); | |
2161 | } | |
2162 | ||
2163 | static void | |
2164 | zvol_task_free(zvol_task_t *task) | |
2165 | { | |
2166 | kmem_free(task, sizeof (zvol_task_t)); | |
2167 | } | |
2168 | ||
2169 | /* | |
2170 | * The worker thread function performed asynchronously. | |
2171 | */ | |
2172 | static void | |
2173 | zvol_task_cb(void *param) | |
2174 | { | |
2175 | zvol_task_t *task = (zvol_task_t *)param; | |
2176 | ||
2177 | switch (task->op) { | |
2178 | case ZVOL_ASYNC_CREATE_MINORS: | |
2179 | (void) zvol_create_minors_impl(task->name1); | |
2180 | break; | |
2181 | case ZVOL_ASYNC_REMOVE_MINORS: | |
2182 | zvol_remove_minors_impl(task->name1); | |
2183 | break; | |
2184 | case ZVOL_ASYNC_RENAME_MINORS: | |
2185 | zvol_rename_minors_impl(task->name1, task->name2); | |
2186 | break; | |
2187 | case ZVOL_ASYNC_SET_SNAPDEV: | |
2188 | zvol_set_snapdev_impl(task->name1, task->snapdev); | |
2189 | break; | |
2190 | default: | |
2191 | VERIFY(0); | |
2192 | break; | |
2193 | } | |
2194 | ||
2195 | zvol_task_free(task); | |
2196 | } | |
2197 | ||
2198 | typedef struct zvol_set_snapdev_arg { | |
2199 | const char *zsda_name; | |
2200 | uint64_t zsda_value; | |
2201 | zprop_source_t zsda_source; | |
2202 | dmu_tx_t *zsda_tx; | |
2203 | } zvol_set_snapdev_arg_t; | |
2204 | ||
2205 | /* | |
2206 | * Sanity check the dataset for safe use by the sync task. No additional | |
2207 | * conditions are imposed. | |
2208 | */ | |
2209 | static int | |
2210 | zvol_set_snapdev_check(void *arg, dmu_tx_t *tx) | |
2211 | { | |
2212 | zvol_set_snapdev_arg_t *zsda = arg; | |
2213 | dsl_pool_t *dp = dmu_tx_pool(tx); | |
2214 | dsl_dir_t *dd; | |
2215 | int error; | |
2216 | ||
2217 | error = dsl_dir_hold(dp, zsda->zsda_name, FTAG, &dd, NULL); | |
2218 | if (error != 0) | |
2219 | return (error); | |
2220 | ||
2221 | dsl_dir_rele(dd, FTAG); | |
2222 | ||
2223 | return (error); | |
2224 | } | |
2225 | ||
92aceb2a | 2226 | /* ARGSUSED */ |
a0bd735a BP |
2227 | static int |
2228 | zvol_set_snapdev_sync_cb(dsl_pool_t *dp, dsl_dataset_t *ds, void *arg) | |
2229 | { | |
a0bd735a BP |
2230 | char dsname[MAXNAMELEN]; |
2231 | zvol_task_t *task; | |
92aceb2a | 2232 | uint64_t snapdev; |
a0bd735a BP |
2233 | |
2234 | dsl_dataset_name(ds, dsname); | |
92aceb2a | 2235 | if (dsl_prop_get_int_ds(ds, "snapdev", &snapdev) != 0) |
2236 | return (0); | |
2237 | task = zvol_task_alloc(ZVOL_ASYNC_SET_SNAPDEV, dsname, NULL, snapdev); | |
a0bd735a BP |
2238 | if (task == NULL) |
2239 | return (0); | |
2240 | ||
2241 | (void) taskq_dispatch(dp->dp_spa->spa_zvol_taskq, zvol_task_cb, | |
02730c33 | 2242 | task, TQ_SLEEP); |
a0bd735a BP |
2243 | return (0); |
2244 | } | |
2245 | ||
2246 | /* | |
92aceb2a | 2247 | * Traverse all child datasets and apply snapdev appropriately. |
2248 | * We call dsl_prop_set_sync_impl() here to set the value only on the toplevel | |
2249 | * dataset and read the effective "snapdev" on every child in the callback | |
2250 | * function: this is because the value is not guaranteed to be the same in the | |
2251 | * whole dataset hierarchy. | |
a0bd735a BP |
2252 | */ |
2253 | static void | |
2254 | zvol_set_snapdev_sync(void *arg, dmu_tx_t *tx) | |
2255 | { | |
2256 | zvol_set_snapdev_arg_t *zsda = arg; | |
2257 | dsl_pool_t *dp = dmu_tx_pool(tx); | |
2258 | dsl_dir_t *dd; | |
92aceb2a | 2259 | dsl_dataset_t *ds; |
2260 | int error; | |
a0bd735a BP |
2261 | |
2262 | VERIFY0(dsl_dir_hold(dp, zsda->zsda_name, FTAG, &dd, NULL)); | |
2263 | zsda->zsda_tx = tx; | |
2264 | ||
92aceb2a | 2265 | error = dsl_dataset_hold(dp, zsda->zsda_name, FTAG, &ds); |
2266 | if (error == 0) { | |
2267 | dsl_prop_set_sync_impl(ds, zfs_prop_to_name(ZFS_PROP_SNAPDEV), | |
2268 | zsda->zsda_source, sizeof (zsda->zsda_value), 1, | |
2269 | &zsda->zsda_value, zsda->zsda_tx); | |
2270 | dsl_dataset_rele(ds, FTAG); | |
2271 | } | |
a0bd735a BP |
2272 | dmu_objset_find_dp(dp, dd->dd_object, zvol_set_snapdev_sync_cb, |
2273 | zsda, DS_FIND_CHILDREN); | |
2274 | ||
2275 | dsl_dir_rele(dd, FTAG); | |
2276 | } | |
2277 | ||
0b4d1b58 | 2278 | int |
a0bd735a BP |
2279 | zvol_set_snapdev(const char *ddname, zprop_source_t source, uint64_t snapdev) |
2280 | { | |
2281 | zvol_set_snapdev_arg_t zsda; | |
5428dc51 | 2282 | |
a0bd735a BP |
2283 | zsda.zsda_name = ddname; |
2284 | zsda.zsda_source = source; | |
2285 | zsda.zsda_value = snapdev; | |
5428dc51 | 2286 | |
a0bd735a BP |
2287 | return (dsl_sync_task(ddname, zvol_set_snapdev_check, |
2288 | zvol_set_snapdev_sync, &zsda, 0, ZFS_SPACE_CHECK_NONE)); | |
2289 | } | |
2290 | ||
2291 | void | |
2292 | zvol_create_minors(spa_t *spa, const char *name, boolean_t async) | |
2293 | { | |
2294 | zvol_task_t *task; | |
2295 | taskqid_t id; | |
2296 | ||
2297 | task = zvol_task_alloc(ZVOL_ASYNC_CREATE_MINORS, name, NULL, ~0ULL); | |
2298 | if (task == NULL) | |
2299 | return; | |
2300 | ||
2301 | id = taskq_dispatch(spa->spa_zvol_taskq, zvol_task_cb, task, TQ_SLEEP); | |
48d3eb40 | 2302 | if ((async == B_FALSE) && (id != TASKQID_INVALID)) |
a0bd735a BP |
2303 | taskq_wait_id(spa->spa_zvol_taskq, id); |
2304 | } | |
2305 | ||
2306 | void | |
2307 | zvol_remove_minors(spa_t *spa, const char *name, boolean_t async) | |
2308 | { | |
2309 | zvol_task_t *task; | |
2310 | taskqid_t id; | |
2311 | ||
2312 | task = zvol_task_alloc(ZVOL_ASYNC_REMOVE_MINORS, name, NULL, ~0ULL); | |
2313 | if (task == NULL) | |
2314 | return; | |
5428dc51 | 2315 | |
a0bd735a | 2316 | id = taskq_dispatch(spa->spa_zvol_taskq, zvol_task_cb, task, TQ_SLEEP); |
48d3eb40 | 2317 | if ((async == B_FALSE) && (id != TASKQID_INVALID)) |
a0bd735a BP |
2318 | taskq_wait_id(spa->spa_zvol_taskq, id); |
2319 | } | |
2320 | ||
2321 | void | |
2322 | zvol_rename_minors(spa_t *spa, const char *name1, const char *name2, | |
2323 | boolean_t async) | |
2324 | { | |
2325 | zvol_task_t *task; | |
2326 | taskqid_t id; | |
2327 | ||
2328 | task = zvol_task_alloc(ZVOL_ASYNC_RENAME_MINORS, name1, name2, ~0ULL); | |
2329 | if (task == NULL) | |
2330 | return; | |
2331 | ||
2332 | id = taskq_dispatch(spa->spa_zvol_taskq, zvol_task_cb, task, TQ_SLEEP); | |
48d3eb40 | 2333 | if ((async == B_FALSE) && (id != TASKQID_INVALID)) |
a0bd735a | 2334 | taskq_wait_id(spa->spa_zvol_taskq, id); |
0b4d1b58 ED |
2335 | } |
2336 | ||
60101509 BB |
2337 | int |
2338 | zvol_init(void) | |
2339 | { | |
692e55b8 | 2340 | int threads = MIN(MAX(zvol_threads, 1), 1024); |
d45e010d | 2341 | int i, error; |
60101509 | 2342 | |
2a3871d4 | 2343 | list_create(&zvol_state_list, sizeof (zvol_state_t), |
ce37ebd2 | 2344 | offsetof(zvol_state_t, zv_next)); |
2a3871d4 | 2345 | mutex_init(&zvol_state_lock, NULL, MUTEX_DEFAULT, NULL); |
4a5d7f82 | 2346 | ida_init(&zvol_ida); |
2a3871d4 | 2347 | |
692e55b8 CC |
2348 | zvol_taskq = taskq_create(ZVOL_DRIVER, threads, maxclsyspri, |
2349 | threads * 2, INT_MAX, TASKQ_PREPOPULATE | TASKQ_DYNAMIC); | |
2350 | if (zvol_taskq == NULL) { | |
2351 | printk(KERN_INFO "ZFS: taskq_create() failed\n"); | |
2352 | error = -ENOMEM; | |
2353 | goto out; | |
2354 | } | |
2355 | ||
d45e010d CC |
2356 | zvol_htable = kmem_alloc(ZVOL_HT_SIZE * sizeof (struct hlist_head), |
2357 | KM_SLEEP); | |
2358 | if (!zvol_htable) { | |
692e55b8 CC |
2359 | error = -ENOMEM; |
2360 | goto out_taskq; | |
d45e010d CC |
2361 | } |
2362 | for (i = 0; i < ZVOL_HT_SIZE; i++) | |
2363 | INIT_HLIST_HEAD(&zvol_htable[i]); | |
2364 | ||
60101509 BB |
2365 | error = register_blkdev(zvol_major, ZVOL_DRIVER); |
2366 | if (error) { | |
2367 | printk(KERN_INFO "ZFS: register_blkdev() failed %d\n", error); | |
d45e010d | 2368 | goto out_free; |
60101509 BB |
2369 | } |
2370 | ||
2371 | blk_register_region(MKDEV(zvol_major, 0), 1UL << MINORBITS, | |
ce37ebd2 | 2372 | THIS_MODULE, zvol_probe, NULL, NULL); |
60101509 | 2373 | |
60101509 | 2374 | return (0); |
2a3871d4 | 2375 | |
d45e010d CC |
2376 | out_free: |
2377 | kmem_free(zvol_htable, ZVOL_HT_SIZE * sizeof (struct hlist_head)); | |
692e55b8 CC |
2378 | out_taskq: |
2379 | taskq_destroy(zvol_taskq); | |
37f9dac5 | 2380 | out: |
2a3871d4 RY |
2381 | mutex_destroy(&zvol_state_lock); |
2382 | list_destroy(&zvol_state_list); | |
2383 | ||
ce37ebd2 | 2384 | return (SET_ERROR(error)); |
60101509 BB |
2385 | } |
2386 | ||
2387 | void | |
2388 | zvol_fini(void) | |
2389 | { | |
a0bd735a BP |
2390 | zvol_remove_minors_impl(NULL); |
2391 | ||
60101509 BB |
2392 | blk_unregister_region(MKDEV(zvol_major, 0), 1UL << MINORBITS); |
2393 | unregister_blkdev(zvol_major, ZVOL_DRIVER); | |
d45e010d | 2394 | kmem_free(zvol_htable, ZVOL_HT_SIZE * sizeof (struct hlist_head)); |
a0bd735a | 2395 | |
692e55b8 | 2396 | taskq_destroy(zvol_taskq); |
60101509 | 2397 | list_destroy(&zvol_state_list); |
a0bd735a | 2398 | mutex_destroy(&zvol_state_lock); |
f2d8bdc6 CC |
2399 | |
2400 | ida_destroy(&zvol_ida); | |
60101509 BB |
2401 | } |
2402 | ||
02730c33 | 2403 | /* BEGIN CSTYLED */ |
74497b7a DH |
2404 | module_param(zvol_inhibit_dev, uint, 0644); |
2405 | MODULE_PARM_DESC(zvol_inhibit_dev, "Do not create zvol device nodes"); | |
2406 | ||
30a9524e | 2407 | module_param(zvol_major, uint, 0444); |
60101509 BB |
2408 | MODULE_PARM_DESC(zvol_major, "Major number for zvol device"); |
2409 | ||
692e55b8 CC |
2410 | module_param(zvol_threads, uint, 0444); |
2411 | MODULE_PARM_DESC(zvol_threads, "Max number of threads to handle I/O requests"); | |
2412 | ||
2413 | module_param(zvol_request_sync, uint, 0644); | |
2414 | MODULE_PARM_DESC(zvol_request_sync, "Synchronously handle bio requests"); | |
2415 | ||
7c0e5708 | 2416 | module_param(zvol_max_discard_blocks, ulong, 0444); |
ce37ebd2 | 2417 | MODULE_PARM_DESC(zvol_max_discard_blocks, "Max number of blocks to discard"); |
9965059a BB |
2418 | |
2419 | module_param(zvol_prefetch_bytes, uint, 0644); | |
2420 | MODULE_PARM_DESC(zvol_prefetch_bytes, "Prefetch N bytes at zvol start+end"); | |
02730c33 | 2421 | /* END CSTYLED */ |