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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. | |
36 | */ | |
37 | ||
03c6040b | 38 | #include <sys/dbuf.h> |
60101509 BB |
39 | #include <sys/dmu_traverse.h> |
40 | #include <sys/dsl_dataset.h> | |
41 | #include <sys/dsl_prop.h> | |
42 | #include <sys/zap.h> | |
4cb7b9c5 | 43 | #include <sys/zfeature.h> |
60101509 BB |
44 | #include <sys/zil_impl.h> |
45 | #include <sys/zio.h> | |
46 | #include <sys/zfs_rlock.h> | |
47 | #include <sys/zfs_znode.h> | |
48 | #include <sys/zvol.h> | |
61e90960 | 49 | #include <linux/blkdev_compat.h> |
60101509 | 50 | |
74497b7a | 51 | unsigned int zvol_inhibit_dev = 0; |
60101509 | 52 | unsigned int zvol_major = ZVOL_MAJOR; |
9965059a | 53 | unsigned int zvol_prefetch_bytes = (128 * 1024); |
7c0e5708 | 54 | unsigned long zvol_max_discard_blocks = 16384; |
60101509 | 55 | |
60101509 BB |
56 | static kmutex_t zvol_state_lock; |
57 | static list_t zvol_state_list; | |
58 | static char *zvol_tag = "zvol_tag"; | |
59 | ||
60 | /* | |
61 | * The in-core state of each volume. | |
62 | */ | |
63 | typedef struct zvol_state { | |
4c0d8e50 | 64 | char zv_name[MAXNAMELEN]; /* name */ |
ce37ebd2 BB |
65 | uint64_t zv_volsize; /* advertised space */ |
66 | uint64_t zv_volblocksize; /* volume block size */ | |
60101509 BB |
67 | objset_t *zv_objset; /* objset handle */ |
68 | uint32_t zv_flags; /* ZVOL_* flags */ | |
69 | uint32_t zv_open_count; /* open counts */ | |
70 | uint32_t zv_changed; /* disk changed */ | |
71 | zilog_t *zv_zilog; /* ZIL handle */ | |
72 | znode_t zv_znode; /* for range locking */ | |
73 | dmu_buf_t *zv_dbuf; /* bonus handle */ | |
74 | dev_t zv_dev; /* device id */ | |
75 | struct gendisk *zv_disk; /* generic disk */ | |
76 | struct request_queue *zv_queue; /* request queue */ | |
60101509 BB |
77 | list_node_t zv_next; /* next zvol_state_t linkage */ |
78 | } zvol_state_t; | |
79 | ||
80 | #define ZVOL_RDONLY 0x1 | |
81 | ||
82 | /* | |
83 | * Find the next available range of ZVOL_MINORS minor numbers. The | |
84 | * zvol_state_list is kept in ascending minor order so we simply need | |
85 | * to scan the list for the first gap in the sequence. This allows us | |
86 | * to recycle minor number as devices are created and removed. | |
87 | */ | |
88 | static int | |
89 | zvol_find_minor(unsigned *minor) | |
90 | { | |
91 | zvol_state_t *zv; | |
92 | ||
93 | *minor = 0; | |
94 | ASSERT(MUTEX_HELD(&zvol_state_lock)); | |
95 | for (zv = list_head(&zvol_state_list); zv != NULL; | |
ce37ebd2 | 96 | zv = list_next(&zvol_state_list, zv), *minor += ZVOL_MINORS) { |
60101509 BB |
97 | if (MINOR(zv->zv_dev) != MINOR(*minor)) |
98 | break; | |
99 | } | |
100 | ||
101 | /* All minors are in use */ | |
102 | if (*minor >= (1 << MINORBITS)) | |
ce37ebd2 | 103 | return (SET_ERROR(ENXIO)); |
60101509 | 104 | |
ce37ebd2 | 105 | return (0); |
60101509 BB |
106 | } |
107 | ||
108 | /* | |
109 | * Find a zvol_state_t given the full major+minor dev_t. | |
110 | */ | |
111 | static zvol_state_t * | |
112 | zvol_find_by_dev(dev_t dev) | |
113 | { | |
114 | zvol_state_t *zv; | |
115 | ||
116 | ASSERT(MUTEX_HELD(&zvol_state_lock)); | |
117 | for (zv = list_head(&zvol_state_list); zv != NULL; | |
ce37ebd2 | 118 | zv = list_next(&zvol_state_list, zv)) { |
60101509 | 119 | if (zv->zv_dev == dev) |
ce37ebd2 | 120 | return (zv); |
60101509 BB |
121 | } |
122 | ||
ce37ebd2 | 123 | return (NULL); |
60101509 BB |
124 | } |
125 | ||
126 | /* | |
127 | * Find a zvol_state_t given the name provided at zvol_alloc() time. | |
128 | */ | |
129 | static zvol_state_t * | |
130 | zvol_find_by_name(const char *name) | |
131 | { | |
132 | zvol_state_t *zv; | |
133 | ||
134 | ASSERT(MUTEX_HELD(&zvol_state_lock)); | |
135 | for (zv = list_head(&zvol_state_list); zv != NULL; | |
ce37ebd2 BB |
136 | zv = list_next(&zvol_state_list, zv)) { |
137 | if (strncmp(zv->zv_name, name, MAXNAMELEN) == 0) | |
138 | return (zv); | |
60101509 BB |
139 | } |
140 | ||
ce37ebd2 | 141 | return (NULL); |
60101509 BB |
142 | } |
143 | ||
6c285672 JL |
144 | |
145 | /* | |
146 | * Given a path, return TRUE if path is a ZVOL. | |
147 | */ | |
148 | boolean_t | |
149 | zvol_is_zvol(const char *device) | |
150 | { | |
151 | struct block_device *bdev; | |
152 | unsigned int major; | |
153 | ||
154 | bdev = lookup_bdev(device); | |
155 | if (IS_ERR(bdev)) | |
156 | return (B_FALSE); | |
157 | ||
158 | major = MAJOR(bdev->bd_dev); | |
159 | bdput(bdev); | |
160 | ||
161 | if (major == zvol_major) | |
ce37ebd2 | 162 | return (B_TRUE); |
6c285672 JL |
163 | |
164 | return (B_FALSE); | |
165 | } | |
166 | ||
60101509 BB |
167 | /* |
168 | * ZFS_IOC_CREATE callback handles dmu zvol and zap object creation. | |
169 | */ | |
170 | void | |
171 | zvol_create_cb(objset_t *os, void *arg, cred_t *cr, dmu_tx_t *tx) | |
172 | { | |
173 | zfs_creat_t *zct = arg; | |
174 | nvlist_t *nvprops = zct->zct_props; | |
175 | int error; | |
176 | uint64_t volblocksize, volsize; | |
177 | ||
178 | VERIFY(nvlist_lookup_uint64(nvprops, | |
179 | zfs_prop_to_name(ZFS_PROP_VOLSIZE), &volsize) == 0); | |
180 | if (nvlist_lookup_uint64(nvprops, | |
181 | zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), &volblocksize) != 0) | |
182 | volblocksize = zfs_prop_default_numeric(ZFS_PROP_VOLBLOCKSIZE); | |
183 | ||
184 | /* | |
185 | * These properties must be removed from the list so the generic | |
186 | * property setting step won't apply to them. | |
187 | */ | |
188 | VERIFY(nvlist_remove_all(nvprops, | |
189 | zfs_prop_to_name(ZFS_PROP_VOLSIZE)) == 0); | |
190 | (void) nvlist_remove_all(nvprops, | |
191 | zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE)); | |
192 | ||
193 | error = dmu_object_claim(os, ZVOL_OBJ, DMU_OT_ZVOL, volblocksize, | |
194 | DMU_OT_NONE, 0, tx); | |
195 | ASSERT(error == 0); | |
196 | ||
197 | error = zap_create_claim(os, ZVOL_ZAP_OBJ, DMU_OT_ZVOL_PROP, | |
198 | DMU_OT_NONE, 0, tx); | |
199 | ASSERT(error == 0); | |
200 | ||
201 | error = zap_update(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize, tx); | |
202 | ASSERT(error == 0); | |
203 | } | |
204 | ||
205 | /* | |
206 | * ZFS_IOC_OBJSET_STATS entry point. | |
207 | */ | |
208 | int | |
209 | zvol_get_stats(objset_t *os, nvlist_t *nv) | |
210 | { | |
211 | int error; | |
212 | dmu_object_info_t *doi; | |
213 | uint64_t val; | |
214 | ||
215 | error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &val); | |
216 | if (error) | |
ce37ebd2 | 217 | return (SET_ERROR(error)); |
60101509 BB |
218 | |
219 | dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_VOLSIZE, val); | |
ce37ebd2 | 220 | doi = kmem_alloc(sizeof (dmu_object_info_t), KM_SLEEP); |
60101509 BB |
221 | error = dmu_object_info(os, ZVOL_OBJ, doi); |
222 | ||
223 | if (error == 0) { | |
224 | dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_VOLBLOCKSIZE, | |
225 | doi->doi_data_block_size); | |
226 | } | |
227 | ||
ce37ebd2 | 228 | kmem_free(doi, sizeof (dmu_object_info_t)); |
60101509 | 229 | |
ce37ebd2 | 230 | return (SET_ERROR(error)); |
60101509 BB |
231 | } |
232 | ||
35d3e322 BB |
233 | static void |
234 | zvol_size_changed(zvol_state_t *zv, uint64_t volsize) | |
235 | { | |
236 | struct block_device *bdev; | |
237 | ||
238 | bdev = bdget_disk(zv->zv_disk, 0); | |
239 | if (bdev == NULL) | |
240 | return; | |
241 | /* | |
242 | * 2.6.28 API change | |
243 | * Added check_disk_size_change() helper function. | |
244 | */ | |
245 | #ifdef HAVE_CHECK_DISK_SIZE_CHANGE | |
246 | set_capacity(zv->zv_disk, volsize >> 9); | |
247 | zv->zv_volsize = volsize; | |
248 | check_disk_size_change(zv->zv_disk, bdev); | |
249 | #else | |
250 | zv->zv_volsize = volsize; | |
251 | zv->zv_changed = 1; | |
252 | (void) check_disk_change(bdev); | |
253 | #endif /* HAVE_CHECK_DISK_SIZE_CHANGE */ | |
254 | ||
255 | bdput(bdev); | |
256 | } | |
257 | ||
60101509 BB |
258 | /* |
259 | * Sanity check volume size. | |
260 | */ | |
261 | int | |
262 | zvol_check_volsize(uint64_t volsize, uint64_t blocksize) | |
263 | { | |
264 | if (volsize == 0) | |
2e528b49 | 265 | return (SET_ERROR(EINVAL)); |
60101509 BB |
266 | |
267 | if (volsize % blocksize != 0) | |
2e528b49 | 268 | return (SET_ERROR(EINVAL)); |
60101509 BB |
269 | |
270 | #ifdef _ILP32 | |
271 | if (volsize - 1 > MAXOFFSET_T) | |
2e528b49 | 272 | return (SET_ERROR(EOVERFLOW)); |
60101509 BB |
273 | #endif |
274 | return (0); | |
275 | } | |
276 | ||
277 | /* | |
278 | * Ensure the zap is flushed then inform the VFS of the capacity change. | |
279 | */ | |
280 | static int | |
35d3e322 | 281 | zvol_update_volsize(uint64_t volsize, objset_t *os) |
60101509 | 282 | { |
60101509 BB |
283 | dmu_tx_t *tx; |
284 | int error; | |
285 | ||
286 | ASSERT(MUTEX_HELD(&zvol_state_lock)); | |
287 | ||
df554c14 | 288 | tx = dmu_tx_create(os); |
60101509 BB |
289 | dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL); |
290 | error = dmu_tx_assign(tx, TXG_WAIT); | |
291 | if (error) { | |
292 | dmu_tx_abort(tx); | |
ce37ebd2 | 293 | return (SET_ERROR(error)); |
60101509 BB |
294 | } |
295 | ||
df554c14 | 296 | error = zap_update(os, ZVOL_ZAP_OBJ, "size", 8, 1, |
60101509 BB |
297 | &volsize, tx); |
298 | dmu_tx_commit(tx); | |
299 | ||
35d3e322 BB |
300 | if (error == 0) |
301 | error = dmu_free_long_range(os, | |
302 | ZVOL_OBJ, volsize, DMU_OBJECT_END); | |
60101509 | 303 | |
35d3e322 BB |
304 | return (error); |
305 | } | |
60101509 | 306 | |
35d3e322 BB |
307 | static int |
308 | zvol_update_live_volsize(zvol_state_t *zv, uint64_t volsize) | |
309 | { | |
310 | zvol_size_changed(zv, volsize); | |
60101509 | 311 | |
35d3e322 BB |
312 | /* |
313 | * We should post a event here describing the expansion. However, | |
314 | * the zfs_ereport_post() interface doesn't nicely support posting | |
315 | * events for zvols, it assumes events relate to vdevs or zios. | |
316 | */ | |
60101509 BB |
317 | |
318 | return (0); | |
319 | } | |
320 | ||
321 | /* | |
322 | * Set ZFS_PROP_VOLSIZE set entry point. | |
323 | */ | |
324 | int | |
325 | zvol_set_volsize(const char *name, uint64_t volsize) | |
326 | { | |
35d3e322 | 327 | zvol_state_t *zv = NULL; |
60101509 | 328 | objset_t *os = NULL; |
60101509 | 329 | int error; |
35d3e322 BB |
330 | dmu_object_info_t *doi; |
331 | uint64_t readonly; | |
332 | boolean_t owned = B_FALSE; | |
60101509 | 333 | |
13fe0198 MA |
334 | error = dsl_prop_get_integer(name, |
335 | zfs_prop_to_name(ZFS_PROP_READONLY), &readonly, NULL); | |
336 | if (error != 0) | |
ce37ebd2 | 337 | return (SET_ERROR(error)); |
13fe0198 | 338 | if (readonly) |
2e528b49 | 339 | return (SET_ERROR(EROFS)); |
13fe0198 | 340 | |
60101509 | 341 | mutex_enter(&zvol_state_lock); |
60101509 | 342 | zv = zvol_find_by_name(name); |
35d3e322 BB |
343 | |
344 | if (zv == NULL || zv->zv_objset == NULL) { | |
345 | if ((error = dmu_objset_own(name, DMU_OST_ZVOL, B_FALSE, | |
346 | FTAG, &os)) != 0) { | |
347 | mutex_exit(&zvol_state_lock); | |
348 | return (SET_ERROR(error)); | |
349 | } | |
350 | owned = B_TRUE; | |
351 | if (zv != NULL) | |
352 | zv->zv_objset = os; | |
353 | } else { | |
354 | os = zv->zv_objset; | |
60101509 BB |
355 | } |
356 | ||
ce37ebd2 | 357 | doi = kmem_alloc(sizeof (dmu_object_info_t), KM_SLEEP); |
60101509 | 358 | |
ce37ebd2 BB |
359 | if ((error = dmu_object_info(os, ZVOL_OBJ, doi)) || |
360 | (error = zvol_check_volsize(volsize, doi->doi_data_block_size))) | |
35d3e322 | 361 | goto out; |
60101509 | 362 | |
35d3e322 | 363 | error = zvol_update_volsize(volsize, os); |
ce37ebd2 | 364 | kmem_free(doi, sizeof (dmu_object_info_t)); |
60101509 | 365 | |
35d3e322 BB |
366 | if (error == 0 && zv != NULL) |
367 | error = zvol_update_live_volsize(zv, volsize); | |
368 | out: | |
369 | if (owned) { | |
370 | dmu_objset_disown(os, FTAG); | |
371 | if (zv != NULL) | |
372 | zv->zv_objset = NULL; | |
373 | } | |
60101509 | 374 | mutex_exit(&zvol_state_lock); |
35d3e322 | 375 | return (error); |
60101509 BB |
376 | } |
377 | ||
378 | /* | |
379 | * Sanity check volume block size. | |
380 | */ | |
381 | int | |
4cb7b9c5 | 382 | zvol_check_volblocksize(const char *name, uint64_t volblocksize) |
60101509 | 383 | { |
4cb7b9c5 BB |
384 | /* Record sizes above 128k need the feature to be enabled */ |
385 | if (volblocksize > SPA_OLD_MAXBLOCKSIZE) { | |
386 | spa_t *spa; | |
387 | int error; | |
388 | ||
389 | if ((error = spa_open(name, &spa, FTAG)) != 0) | |
390 | return (error); | |
391 | ||
392 | if (!spa_feature_is_enabled(spa, SPA_FEATURE_LARGE_BLOCKS)) { | |
393 | spa_close(spa, FTAG); | |
394 | return (SET_ERROR(ENOTSUP)); | |
395 | } | |
396 | ||
397 | /* | |
398 | * We don't allow setting the property above 1MB, | |
399 | * unless the tunable has been changed. | |
400 | */ | |
401 | if (volblocksize > zfs_max_recordsize) | |
402 | return (SET_ERROR(EDOM)); | |
403 | ||
404 | spa_close(spa, FTAG); | |
405 | } | |
406 | ||
60101509 BB |
407 | if (volblocksize < SPA_MINBLOCKSIZE || |
408 | volblocksize > SPA_MAXBLOCKSIZE || | |
409 | !ISP2(volblocksize)) | |
2e528b49 | 410 | return (SET_ERROR(EDOM)); |
60101509 BB |
411 | |
412 | return (0); | |
413 | } | |
414 | ||
415 | /* | |
416 | * Set ZFS_PROP_VOLBLOCKSIZE set entry point. | |
417 | */ | |
418 | int | |
419 | zvol_set_volblocksize(const char *name, uint64_t volblocksize) | |
420 | { | |
421 | zvol_state_t *zv; | |
422 | dmu_tx_t *tx; | |
423 | int error; | |
424 | ||
425 | mutex_enter(&zvol_state_lock); | |
426 | ||
427 | zv = zvol_find_by_name(name); | |
428 | if (zv == NULL) { | |
2e528b49 | 429 | error = SET_ERROR(ENXIO); |
60101509 BB |
430 | goto out; |
431 | } | |
432 | ||
ba6a2402 | 433 | if (zv->zv_flags & ZVOL_RDONLY) { |
2e528b49 | 434 | error = SET_ERROR(EROFS); |
60101509 BB |
435 | goto out; |
436 | } | |
437 | ||
438 | tx = dmu_tx_create(zv->zv_objset); | |
439 | dmu_tx_hold_bonus(tx, ZVOL_OBJ); | |
440 | error = dmu_tx_assign(tx, TXG_WAIT); | |
441 | if (error) { | |
442 | dmu_tx_abort(tx); | |
443 | } else { | |
444 | error = dmu_object_set_blocksize(zv->zv_objset, ZVOL_OBJ, | |
445 | volblocksize, 0, tx); | |
446 | if (error == ENOTSUP) | |
2e528b49 | 447 | error = SET_ERROR(EBUSY); |
60101509 BB |
448 | dmu_tx_commit(tx); |
449 | if (error == 0) | |
450 | zv->zv_volblocksize = volblocksize; | |
451 | } | |
452 | out: | |
453 | mutex_exit(&zvol_state_lock); | |
454 | ||
ce37ebd2 | 455 | return (SET_ERROR(error)); |
60101509 BB |
456 | } |
457 | ||
458 | /* | |
459 | * Replay a TX_WRITE ZIL transaction that didn't get committed | |
460 | * after a system failure | |
461 | */ | |
462 | static int | |
463 | zvol_replay_write(zvol_state_t *zv, lr_write_t *lr, boolean_t byteswap) | |
464 | { | |
465 | objset_t *os = zv->zv_objset; | |
466 | char *data = (char *)(lr + 1); /* data follows lr_write_t */ | |
467 | uint64_t off = lr->lr_offset; | |
468 | uint64_t len = lr->lr_length; | |
469 | dmu_tx_t *tx; | |
470 | int error; | |
471 | ||
472 | if (byteswap) | |
473 | byteswap_uint64_array(lr, sizeof (*lr)); | |
474 | ||
475 | tx = dmu_tx_create(os); | |
476 | dmu_tx_hold_write(tx, ZVOL_OBJ, off, len); | |
477 | error = dmu_tx_assign(tx, TXG_WAIT); | |
478 | if (error) { | |
479 | dmu_tx_abort(tx); | |
480 | } else { | |
481 | dmu_write(os, ZVOL_OBJ, off, len, data, tx); | |
482 | dmu_tx_commit(tx); | |
483 | } | |
484 | ||
ce37ebd2 | 485 | return (SET_ERROR(error)); |
60101509 BB |
486 | } |
487 | ||
488 | static int | |
489 | zvol_replay_err(zvol_state_t *zv, lr_t *lr, boolean_t byteswap) | |
490 | { | |
2e528b49 | 491 | return (SET_ERROR(ENOTSUP)); |
60101509 BB |
492 | } |
493 | ||
494 | /* | |
495 | * Callback vectors for replaying records. | |
496 | * Only TX_WRITE is needed for zvol. | |
497 | */ | |
b01615d5 RY |
498 | zil_replay_func_t zvol_replay_vector[TX_MAX_TYPE] = { |
499 | (zil_replay_func_t)zvol_replay_err, /* no such transaction type */ | |
500 | (zil_replay_func_t)zvol_replay_err, /* TX_CREATE */ | |
501 | (zil_replay_func_t)zvol_replay_err, /* TX_MKDIR */ | |
502 | (zil_replay_func_t)zvol_replay_err, /* TX_MKXATTR */ | |
503 | (zil_replay_func_t)zvol_replay_err, /* TX_SYMLINK */ | |
504 | (zil_replay_func_t)zvol_replay_err, /* TX_REMOVE */ | |
505 | (zil_replay_func_t)zvol_replay_err, /* TX_RMDIR */ | |
506 | (zil_replay_func_t)zvol_replay_err, /* TX_LINK */ | |
507 | (zil_replay_func_t)zvol_replay_err, /* TX_RENAME */ | |
508 | (zil_replay_func_t)zvol_replay_write, /* TX_WRITE */ | |
509 | (zil_replay_func_t)zvol_replay_err, /* TX_TRUNCATE */ | |
510 | (zil_replay_func_t)zvol_replay_err, /* TX_SETATTR */ | |
511 | (zil_replay_func_t)zvol_replay_err, /* TX_ACL */ | |
60101509 BB |
512 | }; |
513 | ||
514 | /* | |
515 | * zvol_log_write() handles synchronous writes using TX_WRITE ZIL transactions. | |
516 | * | |
517 | * We store data in the log buffers if it's small enough. | |
518 | * Otherwise we will later flush the data out via dmu_sync(). | |
519 | */ | |
520 | ssize_t zvol_immediate_write_sz = 32768; | |
521 | ||
522 | static void | |
ce37ebd2 BB |
523 | zvol_log_write(zvol_state_t *zv, dmu_tx_t *tx, uint64_t offset, |
524 | uint64_t size, int sync) | |
60101509 BB |
525 | { |
526 | uint32_t blocksize = zv->zv_volblocksize; | |
527 | zilog_t *zilog = zv->zv_zilog; | |
528 | boolean_t slogging; | |
ab85f845 | 529 | ssize_t immediate_write_sz; |
60101509 BB |
530 | |
531 | if (zil_replaying(zilog, tx)) | |
532 | return; | |
533 | ||
ab85f845 ED |
534 | immediate_write_sz = (zilog->zl_logbias == ZFS_LOGBIAS_THROUGHPUT) |
535 | ? 0 : zvol_immediate_write_sz; | |
536 | slogging = spa_has_slogs(zilog->zl_spa) && | |
537 | (zilog->zl_logbias == ZFS_LOGBIAS_LATENCY); | |
60101509 BB |
538 | |
539 | while (size) { | |
540 | itx_t *itx; | |
541 | lr_write_t *lr; | |
542 | ssize_t len; | |
543 | itx_wr_state_t write_state; | |
544 | ||
545 | /* | |
546 | * Unlike zfs_log_write() we can be called with | |
547 | * up to DMU_MAX_ACCESS/2 (5MB) writes. | |
548 | */ | |
ab85f845 | 549 | if (blocksize > immediate_write_sz && !slogging && |
60101509 BB |
550 | size >= blocksize && offset % blocksize == 0) { |
551 | write_state = WR_INDIRECT; /* uses dmu_sync */ | |
552 | len = blocksize; | |
553 | } else if (sync) { | |
554 | write_state = WR_COPIED; | |
555 | len = MIN(ZIL_MAX_LOG_DATA, size); | |
556 | } else { | |
557 | write_state = WR_NEED_COPY; | |
558 | len = MIN(ZIL_MAX_LOG_DATA, size); | |
559 | } | |
560 | ||
561 | itx = zil_itx_create(TX_WRITE, sizeof (*lr) + | |
562 | (write_state == WR_COPIED ? len : 0)); | |
563 | lr = (lr_write_t *)&itx->itx_lr; | |
564 | if (write_state == WR_COPIED && dmu_read(zv->zv_objset, | |
565 | ZVOL_OBJ, offset, len, lr+1, DMU_READ_NO_PREFETCH) != 0) { | |
566 | zil_itx_destroy(itx); | |
567 | itx = zil_itx_create(TX_WRITE, sizeof (*lr)); | |
568 | lr = (lr_write_t *)&itx->itx_lr; | |
569 | write_state = WR_NEED_COPY; | |
570 | } | |
571 | ||
572 | itx->itx_wr_state = write_state; | |
573 | if (write_state == WR_NEED_COPY) | |
574 | itx->itx_sod += len; | |
575 | lr->lr_foid = ZVOL_OBJ; | |
576 | lr->lr_offset = offset; | |
577 | lr->lr_length = len; | |
578 | lr->lr_blkoff = 0; | |
579 | BP_ZERO(&lr->lr_blkptr); | |
580 | ||
581 | itx->itx_private = zv; | |
582 | itx->itx_sync = sync; | |
583 | ||
584 | (void) zil_itx_assign(zilog, itx, tx); | |
585 | ||
586 | offset += len; | |
587 | size -= len; | |
588 | } | |
589 | } | |
590 | ||
37f9dac5 RY |
591 | static int |
592 | zvol_write(struct bio *bio) | |
60101509 | 593 | { |
37f9dac5 RY |
594 | zvol_state_t *zv = bio->bi_bdev->bd_disk->private_data; |
595 | uint64_t offset = BIO_BI_SECTOR(bio) << 9; | |
596 | uint64_t size = BIO_BI_SIZE(bio); | |
60101509 BB |
597 | int error = 0; |
598 | dmu_tx_t *tx; | |
599 | rl_t *rl; | |
600 | ||
37f9dac5 | 601 | if (bio->bi_rw & VDEV_REQ_FLUSH) |
b18019d2 ED |
602 | zil_commit(zv->zv_zilog, ZVOL_OBJ); |
603 | ||
604 | /* | |
605 | * Some requests are just for flush and nothing else. | |
606 | */ | |
37f9dac5 | 607 | if (size == 0) |
8630650a | 608 | goto out; |
b18019d2 | 609 | |
60101509 BB |
610 | rl = zfs_range_lock(&zv->zv_znode, offset, size, RL_WRITER); |
611 | ||
612 | tx = dmu_tx_create(zv->zv_objset); | |
613 | dmu_tx_hold_write(tx, ZVOL_OBJ, offset, size); | |
614 | ||
615 | /* This will only fail for ENOSPC */ | |
616 | error = dmu_tx_assign(tx, TXG_WAIT); | |
617 | if (error) { | |
618 | dmu_tx_abort(tx); | |
619 | zfs_range_unlock(rl); | |
8630650a | 620 | goto out; |
60101509 BB |
621 | } |
622 | ||
37f9dac5 | 623 | error = dmu_write_bio(zv->zv_objset, ZVOL_OBJ, bio, tx); |
60101509 | 624 | if (error == 0) |
b18019d2 | 625 | zvol_log_write(zv, tx, offset, size, |
37f9dac5 | 626 | !!(bio->bi_rw & VDEV_REQ_FUA)); |
60101509 BB |
627 | |
628 | dmu_tx_commit(tx); | |
629 | zfs_range_unlock(rl); | |
630 | ||
37f9dac5 | 631 | if ((bio->bi_rw & VDEV_REQ_FUA) || |
b18019d2 | 632 | zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS) |
60101509 BB |
633 | zil_commit(zv->zv_zilog, ZVOL_OBJ); |
634 | ||
8630650a | 635 | out: |
37f9dac5 | 636 | return (error); |
60101509 BB |
637 | } |
638 | ||
37f9dac5 RY |
639 | static int |
640 | zvol_discard(struct bio *bio) | |
30930fba | 641 | { |
37f9dac5 RY |
642 | zvol_state_t *zv = bio->bi_bdev->bd_disk->private_data; |
643 | uint64_t start = BIO_BI_SECTOR(bio) << 9; | |
644 | uint64_t size = BIO_BI_SIZE(bio); | |
645 | uint64_t end = start + size; | |
30930fba ED |
646 | int error; |
647 | rl_t *rl; | |
648 | ||
37f9dac5 RY |
649 | if (end > zv->zv_volsize) |
650 | return (SET_ERROR(EIO)); | |
30930fba | 651 | |
089fa91b | 652 | /* |
fa565676 RY |
653 | * Align the request to volume block boundaries when REQ_SECURE is |
654 | * available, but not requested. If we don't, then this will force | |
655 | * dnode_free_range() to zero out the unaligned parts, which is slow | |
656 | * (read-modify-write) and useless since we are not freeing any space | |
657 | * by doing so. Kernels that do not support REQ_SECURE (2.6.32 through | |
658 | * 2.6.35) will not receive this optimization. | |
089fa91b | 659 | */ |
fa565676 RY |
660 | #ifdef REQ_SECURE |
661 | if (!(bio->bi_rw & REQ_SECURE)) { | |
662 | start = P2ROUNDUP(start, zv->zv_volblocksize); | |
663 | end = P2ALIGN(end, zv->zv_volblocksize); | |
f52ebcb3 | 664 | size = end - start; |
fa565676 RY |
665 | } |
666 | #endif | |
089fa91b | 667 | |
37f9dac5 RY |
668 | if (start >= end) |
669 | return (0); | |
30930fba | 670 | |
37f9dac5 | 671 | rl = zfs_range_lock(&zv->zv_znode, start, size, RL_WRITER); |
30930fba | 672 | |
37f9dac5 | 673 | error = dmu_free_long_range(zv->zv_objset, ZVOL_OBJ, start, size); |
30930fba ED |
674 | |
675 | /* | |
676 | * TODO: maybe we should add the operation to the log. | |
677 | */ | |
678 | ||
679 | zfs_range_unlock(rl); | |
37f9dac5 RY |
680 | |
681 | return (error); | |
30930fba | 682 | } |
30930fba | 683 | |
37f9dac5 RY |
684 | static int |
685 | zvol_read(struct bio *bio) | |
60101509 | 686 | { |
37f9dac5 RY |
687 | zvol_state_t *zv = bio->bi_bdev->bd_disk->private_data; |
688 | uint64_t offset = BIO_BI_SECTOR(bio) << 9; | |
689 | uint64_t len = BIO_BI_SIZE(bio); | |
60101509 BB |
690 | int error; |
691 | rl_t *rl; | |
692 | ||
37f9dac5 RY |
693 | if (len == 0) |
694 | return (0); | |
695 | ||
b18019d2 | 696 | |
37f9dac5 | 697 | rl = zfs_range_lock(&zv->zv_znode, offset, len, RL_READER); |
60101509 | 698 | |
37f9dac5 | 699 | error = dmu_read_bio(zv->zv_objset, ZVOL_OBJ, bio); |
60101509 BB |
700 | |
701 | zfs_range_unlock(rl); | |
702 | ||
703 | /* convert checksum errors into IO errors */ | |
704 | if (error == ECKSUM) | |
2e528b49 | 705 | error = SET_ERROR(EIO); |
60101509 | 706 | |
37f9dac5 | 707 | return (error); |
60101509 BB |
708 | } |
709 | ||
37f9dac5 RY |
710 | static MAKE_REQUEST_FN_RET |
711 | zvol_request(struct request_queue *q, struct bio *bio) | |
60101509 BB |
712 | { |
713 | zvol_state_t *zv = q->queuedata; | |
37f9dac5 RY |
714 | fstrans_cookie_t cookie = spl_fstrans_mark(); |
715 | uint64_t offset = BIO_BI_SECTOR(bio); | |
716 | unsigned int sectors = bio_sectors(bio); | |
8198d18c RY |
717 | int rw = bio_data_dir(bio); |
718 | #ifdef HAVE_GENERIC_IO_ACCT | |
719 | unsigned long start = jiffies; | |
720 | #endif | |
37f9dac5 | 721 | int error = 0; |
60101509 | 722 | |
37f9dac5 RY |
723 | if (bio_has_data(bio) && offset + sectors > |
724 | get_capacity(zv->zv_disk)) { | |
725 | printk(KERN_INFO | |
726 | "%s: bad access: block=%llu, count=%lu\n", | |
727 | zv->zv_disk->disk_name, | |
728 | (long long unsigned)offset, | |
729 | (long unsigned)sectors); | |
730 | error = SET_ERROR(EIO); | |
8198d18c | 731 | goto out1; |
37f9dac5 RY |
732 | } |
733 | ||
8198d18c RY |
734 | generic_start_io_acct(rw, sectors, &zv->zv_disk->part0); |
735 | ||
736 | if (rw == WRITE) { | |
37f9dac5 RY |
737 | if (unlikely(zv->zv_flags & ZVOL_RDONLY)) { |
738 | error = SET_ERROR(EROFS); | |
8198d18c | 739 | goto out2; |
60101509 BB |
740 | } |
741 | ||
37f9dac5 RY |
742 | if (bio->bi_rw & VDEV_REQ_DISCARD) { |
743 | error = zvol_discard(bio); | |
8198d18c | 744 | goto out2; |
37f9dac5 | 745 | } |
60101509 | 746 | |
37f9dac5 RY |
747 | error = zvol_write(bio); |
748 | } else | |
749 | error = zvol_read(bio); | |
30930fba | 750 | |
8198d18c RY |
751 | out2: |
752 | generic_end_io_acct(rw, &zv->zv_disk->part0, start); | |
753 | out1: | |
784a7fe5 | 754 | BIO_END_IO(bio, -error); |
37f9dac5 RY |
755 | spl_fstrans_unmark(cookie); |
756 | #ifdef HAVE_MAKE_REQUEST_FN_RET_INT | |
757 | return (0); | |
1a093716 CC |
758 | #elif defined(HAVE_MAKE_REQUEST_FN_RET_QC) |
759 | return (BLK_QC_T_NONE); | |
37f9dac5 | 760 | #endif |
60101509 BB |
761 | } |
762 | ||
763 | static void | |
764 | zvol_get_done(zgd_t *zgd, int error) | |
765 | { | |
766 | if (zgd->zgd_db) | |
767 | dmu_buf_rele(zgd->zgd_db, zgd); | |
768 | ||
769 | zfs_range_unlock(zgd->zgd_rl); | |
770 | ||
771 | if (error == 0 && zgd->zgd_bp) | |
772 | zil_add_block(zgd->zgd_zilog, zgd->zgd_bp); | |
773 | ||
774 | kmem_free(zgd, sizeof (zgd_t)); | |
775 | } | |
776 | ||
777 | /* | |
778 | * Get data to generate a TX_WRITE intent log record. | |
779 | */ | |
780 | static int | |
781 | zvol_get_data(void *arg, lr_write_t *lr, char *buf, zio_t *zio) | |
782 | { | |
783 | zvol_state_t *zv = arg; | |
784 | objset_t *os = zv->zv_objset; | |
03c6040b | 785 | uint64_t object = ZVOL_OBJ; |
60101509 BB |
786 | uint64_t offset = lr->lr_offset; |
787 | uint64_t size = lr->lr_length; | |
03c6040b | 788 | blkptr_t *bp = &lr->lr_blkptr; |
60101509 BB |
789 | dmu_buf_t *db; |
790 | zgd_t *zgd; | |
791 | int error; | |
792 | ||
793 | ASSERT(zio != NULL); | |
794 | ASSERT(size != 0); | |
795 | ||
79c76d5b | 796 | zgd = (zgd_t *)kmem_zalloc(sizeof (zgd_t), KM_SLEEP); |
60101509 BB |
797 | zgd->zgd_zilog = zv->zv_zilog; |
798 | zgd->zgd_rl = zfs_range_lock(&zv->zv_znode, offset, size, RL_READER); | |
799 | ||
800 | /* | |
801 | * Write records come in two flavors: immediate and indirect. | |
802 | * For small writes it's cheaper to store the data with the | |
803 | * log record (immediate); for large writes it's cheaper to | |
804 | * sync the data and get a pointer to it (indirect) so that | |
805 | * we don't have to write the data twice. | |
806 | */ | |
807 | if (buf != NULL) { /* immediate write */ | |
03c6040b | 808 | error = dmu_read(os, object, offset, size, buf, |
60101509 BB |
809 | DMU_READ_NO_PREFETCH); |
810 | } else { | |
811 | size = zv->zv_volblocksize; | |
812 | offset = P2ALIGN_TYPED(offset, size, uint64_t); | |
03c6040b | 813 | error = dmu_buf_hold(os, object, offset, zgd, &db, |
60101509 BB |
814 | DMU_READ_NO_PREFETCH); |
815 | if (error == 0) { | |
03c6040b GW |
816 | blkptr_t *obp = dmu_buf_get_blkptr(db); |
817 | if (obp) { | |
818 | ASSERT(BP_IS_HOLE(bp)); | |
819 | *bp = *obp; | |
820 | } | |
821 | ||
60101509 BB |
822 | zgd->zgd_db = db; |
823 | zgd->zgd_bp = &lr->lr_blkptr; | |
824 | ||
825 | ASSERT(db != NULL); | |
826 | ASSERT(db->db_offset == offset); | |
827 | ASSERT(db->db_size == size); | |
828 | ||
829 | error = dmu_sync(zio, lr->lr_common.lrc_txg, | |
830 | zvol_get_done, zgd); | |
831 | ||
832 | if (error == 0) | |
833 | return (0); | |
834 | } | |
835 | } | |
836 | ||
837 | zvol_get_done(zgd, error); | |
838 | ||
ce37ebd2 | 839 | return (SET_ERROR(error)); |
60101509 BB |
840 | } |
841 | ||
842 | /* | |
843 | * The zvol_state_t's are inserted in increasing MINOR(dev_t) order. | |
844 | */ | |
845 | static void | |
846 | zvol_insert(zvol_state_t *zv_insert) | |
847 | { | |
848 | zvol_state_t *zv = NULL; | |
849 | ||
850 | ASSERT(MUTEX_HELD(&zvol_state_lock)); | |
851 | ASSERT3U(MINOR(zv_insert->zv_dev) & ZVOL_MINOR_MASK, ==, 0); | |
852 | for (zv = list_head(&zvol_state_list); zv != NULL; | |
ce37ebd2 | 853 | zv = list_next(&zvol_state_list, zv)) { |
60101509 BB |
854 | if (MINOR(zv->zv_dev) > MINOR(zv_insert->zv_dev)) |
855 | break; | |
856 | } | |
857 | ||
858 | list_insert_before(&zvol_state_list, zv, zv_insert); | |
859 | } | |
860 | ||
861 | /* | |
862 | * Simply remove the zvol from to list of zvols. | |
863 | */ | |
864 | static void | |
865 | zvol_remove(zvol_state_t *zv_remove) | |
866 | { | |
867 | ASSERT(MUTEX_HELD(&zvol_state_lock)); | |
868 | list_remove(&zvol_state_list, zv_remove); | |
869 | } | |
870 | ||
871 | static int | |
872 | zvol_first_open(zvol_state_t *zv) | |
873 | { | |
874 | objset_t *os; | |
875 | uint64_t volsize; | |
65d56083 | 876 | int locked = 0; |
60101509 BB |
877 | int error; |
878 | uint64_t ro; | |
879 | ||
65d56083 BB |
880 | /* |
881 | * In all other cases the spa_namespace_lock is taken before the | |
882 | * bdev->bd_mutex lock. But in this case the Linux __blkdev_get() | |
883 | * function calls fops->open() with the bdev->bd_mutex lock held. | |
884 | * | |
885 | * To avoid a potential lock inversion deadlock we preemptively | |
886 | * try to take the spa_namespace_lock(). Normally it will not | |
887 | * be contended and this is safe because spa_open_common() handles | |
888 | * the case where the caller already holds the spa_namespace_lock. | |
889 | * | |
890 | * When it is contended we risk a lock inversion if we were to | |
891 | * block waiting for the lock. Luckily, the __blkdev_get() | |
892 | * function allows us to return -ERESTARTSYS which will result in | |
893 | * bdev->bd_mutex being dropped, reacquired, and fops->open() being | |
894 | * called again. This process can be repeated safely until both | |
895 | * locks are acquired. | |
896 | */ | |
897 | if (!mutex_owned(&spa_namespace_lock)) { | |
898 | locked = mutex_tryenter(&spa_namespace_lock); | |
899 | if (!locked) | |
2e528b49 | 900 | return (-SET_ERROR(ERESTARTSYS)); |
65d56083 BB |
901 | } |
902 | ||
a127e841 BB |
903 | error = dsl_prop_get_integer(zv->zv_name, "readonly", &ro, NULL); |
904 | if (error) | |
905 | goto out_mutex; | |
906 | ||
60101509 BB |
907 | /* lie and say we're read-only */ |
908 | error = dmu_objset_own(zv->zv_name, DMU_OST_ZVOL, 1, zvol_tag, &os); | |
909 | if (error) | |
babf3f9b | 910 | goto out_mutex; |
60101509 BB |
911 | |
912 | error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize); | |
913 | if (error) { | |
babf3f9b MM |
914 | dmu_objset_disown(os, zvol_tag); |
915 | goto out_mutex; | |
60101509 BB |
916 | } |
917 | ||
918 | zv->zv_objset = os; | |
919 | error = dmu_bonus_hold(os, ZVOL_OBJ, zvol_tag, &zv->zv_dbuf); | |
920 | if (error) { | |
babf3f9b MM |
921 | dmu_objset_disown(os, zvol_tag); |
922 | goto out_mutex; | |
60101509 BB |
923 | } |
924 | ||
925 | set_capacity(zv->zv_disk, volsize >> 9); | |
926 | zv->zv_volsize = volsize; | |
927 | zv->zv_zilog = zil_open(os, zvol_get_data); | |
928 | ||
a4430fce GW |
929 | if (ro || dmu_objset_is_snapshot(os) || |
930 | !spa_writeable(dmu_objset_spa(os))) { | |
babf3f9b MM |
931 | set_disk_ro(zv->zv_disk, 1); |
932 | zv->zv_flags |= ZVOL_RDONLY; | |
60101509 | 933 | } else { |
babf3f9b MM |
934 | set_disk_ro(zv->zv_disk, 0); |
935 | zv->zv_flags &= ~ZVOL_RDONLY; | |
60101509 BB |
936 | } |
937 | ||
babf3f9b MM |
938 | out_mutex: |
939 | if (locked) | |
940 | mutex_exit(&spa_namespace_lock); | |
941 | ||
ce37ebd2 | 942 | return (SET_ERROR(-error)); |
60101509 BB |
943 | } |
944 | ||
945 | static void | |
946 | zvol_last_close(zvol_state_t *zv) | |
947 | { | |
948 | zil_close(zv->zv_zilog); | |
949 | zv->zv_zilog = NULL; | |
04434775 | 950 | |
60101509 BB |
951 | dmu_buf_rele(zv->zv_dbuf, zvol_tag); |
952 | zv->zv_dbuf = NULL; | |
04434775 MA |
953 | |
954 | /* | |
955 | * Evict cached data | |
956 | */ | |
957 | if (dsl_dataset_is_dirty(dmu_objset_ds(zv->zv_objset)) && | |
958 | !(zv->zv_flags & ZVOL_RDONLY)) | |
959 | txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0); | |
960 | (void) dmu_objset_evict_dbufs(zv->zv_objset); | |
961 | ||
60101509 BB |
962 | dmu_objset_disown(zv->zv_objset, zvol_tag); |
963 | zv->zv_objset = NULL; | |
964 | } | |
965 | ||
966 | static int | |
967 | zvol_open(struct block_device *bdev, fmode_t flag) | |
968 | { | |
969 | zvol_state_t *zv = bdev->bd_disk->private_data; | |
970 | int error = 0, drop_mutex = 0; | |
971 | ||
972 | /* | |
973 | * If the caller is already holding the mutex do not take it | |
974 | * again, this will happen as part of zvol_create_minor(). | |
975 | * Once add_disk() is called the device is live and the kernel | |
976 | * will attempt to open it to read the partition information. | |
977 | */ | |
978 | if (!mutex_owned(&zvol_state_lock)) { | |
979 | mutex_enter(&zvol_state_lock); | |
980 | drop_mutex = 1; | |
981 | } | |
982 | ||
983 | ASSERT3P(zv, !=, NULL); | |
984 | ||
985 | if (zv->zv_open_count == 0) { | |
986 | error = zvol_first_open(zv); | |
987 | if (error) | |
988 | goto out_mutex; | |
989 | } | |
990 | ||
ba6a2402 | 991 | if ((flag & FMODE_WRITE) && (zv->zv_flags & ZVOL_RDONLY)) { |
60101509 BB |
992 | error = -EROFS; |
993 | goto out_open_count; | |
994 | } | |
995 | ||
996 | zv->zv_open_count++; | |
997 | ||
998 | out_open_count: | |
999 | if (zv->zv_open_count == 0) | |
1000 | zvol_last_close(zv); | |
1001 | ||
1002 | out_mutex: | |
1003 | if (drop_mutex) | |
1004 | mutex_exit(&zvol_state_lock); | |
1005 | ||
1006 | check_disk_change(bdev); | |
1007 | ||
ce37ebd2 | 1008 | return (SET_ERROR(error)); |
60101509 BB |
1009 | } |
1010 | ||
a1d9543a CD |
1011 | #ifdef HAVE_BLOCK_DEVICE_OPERATIONS_RELEASE_VOID |
1012 | static void | |
1013 | #else | |
60101509 | 1014 | static int |
a1d9543a | 1015 | #endif |
60101509 BB |
1016 | zvol_release(struct gendisk *disk, fmode_t mode) |
1017 | { | |
1018 | zvol_state_t *zv = disk->private_data; | |
1019 | int drop_mutex = 0; | |
1020 | ||
1021 | if (!mutex_owned(&zvol_state_lock)) { | |
1022 | mutex_enter(&zvol_state_lock); | |
1023 | drop_mutex = 1; | |
1024 | } | |
1025 | ||
0365064a BB |
1026 | if (zv->zv_open_count > 0) { |
1027 | zv->zv_open_count--; | |
1028 | if (zv->zv_open_count == 0) | |
1029 | zvol_last_close(zv); | |
1030 | } | |
60101509 BB |
1031 | |
1032 | if (drop_mutex) | |
1033 | mutex_exit(&zvol_state_lock); | |
1034 | ||
a1d9543a | 1035 | #ifndef HAVE_BLOCK_DEVICE_OPERATIONS_RELEASE_VOID |
60101509 | 1036 | return (0); |
a1d9543a | 1037 | #endif |
60101509 BB |
1038 | } |
1039 | ||
1040 | static int | |
1041 | zvol_ioctl(struct block_device *bdev, fmode_t mode, | |
ce37ebd2 | 1042 | unsigned int cmd, unsigned long arg) |
60101509 BB |
1043 | { |
1044 | zvol_state_t *zv = bdev->bd_disk->private_data; | |
1045 | int error = 0; | |
1046 | ||
1047 | if (zv == NULL) | |
ce37ebd2 | 1048 | return (SET_ERROR(-ENXIO)); |
60101509 BB |
1049 | |
1050 | switch (cmd) { | |
1051 | case BLKFLSBUF: | |
1052 | zil_commit(zv->zv_zilog, ZVOL_OBJ); | |
1053 | break; | |
4c0d8e50 FN |
1054 | case BLKZNAME: |
1055 | error = copy_to_user((void *)arg, zv->zv_name, MAXNAMELEN); | |
1056 | break; | |
60101509 BB |
1057 | |
1058 | default: | |
1059 | error = -ENOTTY; | |
1060 | break; | |
1061 | ||
1062 | } | |
1063 | ||
ce37ebd2 | 1064 | return (SET_ERROR(error)); |
60101509 BB |
1065 | } |
1066 | ||
1067 | #ifdef CONFIG_COMPAT | |
1068 | static int | |
1069 | zvol_compat_ioctl(struct block_device *bdev, fmode_t mode, | |
ce37ebd2 | 1070 | unsigned cmd, unsigned long arg) |
60101509 | 1071 | { |
ce37ebd2 | 1072 | return (zvol_ioctl(bdev, mode, cmd, arg)); |
60101509 BB |
1073 | } |
1074 | #else | |
ce37ebd2 | 1075 | #define zvol_compat_ioctl NULL |
60101509 BB |
1076 | #endif |
1077 | ||
1078 | static int zvol_media_changed(struct gendisk *disk) | |
1079 | { | |
1080 | zvol_state_t *zv = disk->private_data; | |
1081 | ||
ce37ebd2 | 1082 | return (zv->zv_changed); |
60101509 BB |
1083 | } |
1084 | ||
1085 | static int zvol_revalidate_disk(struct gendisk *disk) | |
1086 | { | |
1087 | zvol_state_t *zv = disk->private_data; | |
1088 | ||
1089 | zv->zv_changed = 0; | |
1090 | set_capacity(zv->zv_disk, zv->zv_volsize >> 9); | |
1091 | ||
ce37ebd2 | 1092 | return (0); |
60101509 BB |
1093 | } |
1094 | ||
1095 | /* | |
1096 | * Provide a simple virtual geometry for legacy compatibility. For devices | |
1097 | * smaller than 1 MiB a small head and sector count is used to allow very | |
1098 | * tiny devices. For devices over 1 Mib a standard head and sector count | |
1099 | * is used to keep the cylinders count reasonable. | |
1100 | */ | |
1101 | static int | |
1102 | zvol_getgeo(struct block_device *bdev, struct hd_geometry *geo) | |
1103 | { | |
1104 | zvol_state_t *zv = bdev->bd_disk->private_data; | |
1105 | sector_t sectors = get_capacity(zv->zv_disk); | |
1106 | ||
1107 | if (sectors > 2048) { | |
1108 | geo->heads = 16; | |
1109 | geo->sectors = 63; | |
1110 | } else { | |
1111 | geo->heads = 2; | |
1112 | geo->sectors = 4; | |
1113 | } | |
1114 | ||
1115 | geo->start = 0; | |
1116 | geo->cylinders = sectors / (geo->heads * geo->sectors); | |
1117 | ||
ce37ebd2 | 1118 | return (0); |
60101509 BB |
1119 | } |
1120 | ||
1121 | static struct kobject * | |
1122 | zvol_probe(dev_t dev, int *part, void *arg) | |
1123 | { | |
1124 | zvol_state_t *zv; | |
1125 | struct kobject *kobj; | |
1126 | ||
1127 | mutex_enter(&zvol_state_lock); | |
1128 | zv = zvol_find_by_dev(dev); | |
23a61ccc | 1129 | kobj = zv ? get_disk(zv->zv_disk) : NULL; |
60101509 BB |
1130 | mutex_exit(&zvol_state_lock); |
1131 | ||
ce37ebd2 | 1132 | return (kobj); |
60101509 BB |
1133 | } |
1134 | ||
1135 | #ifdef HAVE_BDEV_BLOCK_DEVICE_OPERATIONS | |
1136 | static struct block_device_operations zvol_ops = { | |
ce37ebd2 BB |
1137 | .open = zvol_open, |
1138 | .release = zvol_release, | |
1139 | .ioctl = zvol_ioctl, | |
1140 | .compat_ioctl = zvol_compat_ioctl, | |
1141 | .media_changed = zvol_media_changed, | |
1142 | .revalidate_disk = zvol_revalidate_disk, | |
1143 | .getgeo = zvol_getgeo, | |
1144 | .owner = THIS_MODULE, | |
60101509 BB |
1145 | }; |
1146 | ||
1147 | #else /* HAVE_BDEV_BLOCK_DEVICE_OPERATIONS */ | |
1148 | ||
1149 | static int | |
1150 | zvol_open_by_inode(struct inode *inode, struct file *file) | |
1151 | { | |
ce37ebd2 | 1152 | return (zvol_open(inode->i_bdev, file->f_mode)); |
60101509 BB |
1153 | } |
1154 | ||
1155 | static int | |
1156 | zvol_release_by_inode(struct inode *inode, struct file *file) | |
1157 | { | |
ce37ebd2 | 1158 | return (zvol_release(inode->i_bdev->bd_disk, file->f_mode)); |
60101509 BB |
1159 | } |
1160 | ||
1161 | static int | |
1162 | zvol_ioctl_by_inode(struct inode *inode, struct file *file, | |
ce37ebd2 | 1163 | unsigned int cmd, unsigned long arg) |
60101509 | 1164 | { |
b1c58213 | 1165 | if (file == NULL || inode == NULL) |
ce37ebd2 BB |
1166 | return (SET_ERROR(-EINVAL)); |
1167 | ||
1168 | return (zvol_ioctl(inode->i_bdev, file->f_mode, cmd, arg)); | |
60101509 BB |
1169 | } |
1170 | ||
ce37ebd2 | 1171 | #ifdef CONFIG_COMPAT |
60101509 BB |
1172 | static long |
1173 | zvol_compat_ioctl_by_inode(struct file *file, | |
ce37ebd2 | 1174 | unsigned int cmd, unsigned long arg) |
60101509 | 1175 | { |
b1c58213 | 1176 | if (file == NULL) |
ce37ebd2 BB |
1177 | return (SET_ERROR(-EINVAL)); |
1178 | ||
1179 | return (zvol_compat_ioctl(file->f_dentry->d_inode->i_bdev, | |
1180 | file->f_mode, cmd, arg)); | |
60101509 | 1181 | } |
ce37ebd2 BB |
1182 | #else |
1183 | #define zvol_compat_ioctl_by_inode NULL | |
1184 | #endif | |
60101509 BB |
1185 | |
1186 | static struct block_device_operations zvol_ops = { | |
ce37ebd2 BB |
1187 | .open = zvol_open_by_inode, |
1188 | .release = zvol_release_by_inode, | |
1189 | .ioctl = zvol_ioctl_by_inode, | |
1190 | .compat_ioctl = zvol_compat_ioctl_by_inode, | |
1191 | .media_changed = zvol_media_changed, | |
1192 | .revalidate_disk = zvol_revalidate_disk, | |
1193 | .getgeo = zvol_getgeo, | |
1194 | .owner = THIS_MODULE, | |
60101509 BB |
1195 | }; |
1196 | #endif /* HAVE_BDEV_BLOCK_DEVICE_OPERATIONS */ | |
1197 | ||
1198 | /* | |
1199 | * Allocate memory for a new zvol_state_t and setup the required | |
1200 | * request queue and generic disk structures for the block device. | |
1201 | */ | |
1202 | static zvol_state_t * | |
1203 | zvol_alloc(dev_t dev, const char *name) | |
1204 | { | |
1205 | zvol_state_t *zv; | |
1206 | ||
79c76d5b | 1207 | zv = kmem_zalloc(sizeof (zvol_state_t), KM_SLEEP); |
60101509 | 1208 | |
2a3871d4 RY |
1209 | list_link_init(&zv->zv_next); |
1210 | ||
37f9dac5 | 1211 | zv->zv_queue = blk_alloc_queue(GFP_ATOMIC); |
60101509 BB |
1212 | if (zv->zv_queue == NULL) |
1213 | goto out_kmem; | |
1214 | ||
37f9dac5 | 1215 | blk_queue_make_request(zv->zv_queue, zvol_request); |
7bd04f2d | 1216 | |
b18019d2 ED |
1217 | #ifdef HAVE_BLK_QUEUE_FLUSH |
1218 | blk_queue_flush(zv->zv_queue, VDEV_REQ_FLUSH | VDEV_REQ_FUA); | |
1219 | #else | |
1220 | blk_queue_ordered(zv->zv_queue, QUEUE_ORDERED_DRAIN, NULL); | |
1221 | #endif /* HAVE_BLK_QUEUE_FLUSH */ | |
1222 | ||
60101509 BB |
1223 | zv->zv_disk = alloc_disk(ZVOL_MINORS); |
1224 | if (zv->zv_disk == NULL) | |
1225 | goto out_queue; | |
1226 | ||
1227 | zv->zv_queue->queuedata = zv; | |
1228 | zv->zv_dev = dev; | |
1229 | zv->zv_open_count = 0; | |
4c0d8e50 | 1230 | strlcpy(zv->zv_name, name, MAXNAMELEN); |
60101509 BB |
1231 | |
1232 | mutex_init(&zv->zv_znode.z_range_lock, NULL, MUTEX_DEFAULT, NULL); | |
1233 | avl_create(&zv->zv_znode.z_range_avl, zfs_range_compare, | |
1234 | sizeof (rl_t), offsetof(rl_t, r_node)); | |
3c4988c8 BB |
1235 | zv->zv_znode.z_is_zvol = TRUE; |
1236 | ||
60101509 BB |
1237 | zv->zv_disk->major = zvol_major; |
1238 | zv->zv_disk->first_minor = (dev & MINORMASK); | |
1239 | zv->zv_disk->fops = &zvol_ops; | |
1240 | zv->zv_disk->private_data = zv; | |
1241 | zv->zv_disk->queue = zv->zv_queue; | |
4c0d8e50 FN |
1242 | snprintf(zv->zv_disk->disk_name, DISK_NAME_LEN, "%s%d", |
1243 | ZVOL_DEV_NAME, (dev & MINORMASK)); | |
60101509 | 1244 | |
ce37ebd2 | 1245 | return (zv); |
60101509 BB |
1246 | |
1247 | out_queue: | |
1248 | blk_cleanup_queue(zv->zv_queue); | |
1249 | out_kmem: | |
1250 | kmem_free(zv, sizeof (zvol_state_t)); | |
0a6bef26 | 1251 | |
ce37ebd2 | 1252 | return (NULL); |
60101509 BB |
1253 | } |
1254 | ||
1255 | /* | |
1256 | * Cleanup then free a zvol_state_t which was created by zvol_alloc(). | |
1257 | */ | |
1258 | static void | |
1259 | zvol_free(zvol_state_t *zv) | |
1260 | { | |
1261 | avl_destroy(&zv->zv_znode.z_range_avl); | |
1262 | mutex_destroy(&zv->zv_znode.z_range_lock); | |
1263 | ||
1264 | del_gendisk(zv->zv_disk); | |
1265 | blk_cleanup_queue(zv->zv_queue); | |
1266 | put_disk(zv->zv_disk); | |
1267 | ||
1268 | kmem_free(zv, sizeof (zvol_state_t)); | |
1269 | } | |
1270 | ||
1271 | static int | |
0b4d1b58 ED |
1272 | __zvol_snapdev_hidden(const char *name) |
1273 | { | |
ce37ebd2 BB |
1274 | uint64_t snapdev; |
1275 | char *parent; | |
1276 | char *atp; | |
1277 | int error = 0; | |
1278 | ||
79c76d5b | 1279 | parent = kmem_alloc(MAXPATHLEN, KM_SLEEP); |
ce37ebd2 BB |
1280 | (void) strlcpy(parent, name, MAXPATHLEN); |
1281 | ||
1282 | if ((atp = strrchr(parent, '@')) != NULL) { | |
1283 | *atp = '\0'; | |
1284 | error = dsl_prop_get_integer(parent, "snapdev", &snapdev, NULL); | |
1285 | if ((error == 0) && (snapdev == ZFS_SNAPDEV_HIDDEN)) | |
1286 | error = SET_ERROR(ENODEV); | |
1287 | } | |
1288 | ||
1289 | kmem_free(parent, MAXPATHLEN); | |
1290 | ||
1291 | return (SET_ERROR(error)); | |
0b4d1b58 ED |
1292 | } |
1293 | ||
1294 | static int | |
1295 | __zvol_create_minor(const char *name, boolean_t ignore_snapdev) | |
60101509 BB |
1296 | { |
1297 | zvol_state_t *zv; | |
1298 | objset_t *os; | |
1299 | dmu_object_info_t *doi; | |
1300 | uint64_t volsize; | |
9965059a | 1301 | uint64_t len; |
60101509 BB |
1302 | unsigned minor = 0; |
1303 | int error = 0; | |
1304 | ||
1305 | ASSERT(MUTEX_HELD(&zvol_state_lock)); | |
1306 | ||
1307 | zv = zvol_find_by_name(name); | |
1308 | if (zv) { | |
2e528b49 | 1309 | error = SET_ERROR(EEXIST); |
60101509 BB |
1310 | goto out; |
1311 | } | |
1312 | ||
0b4d1b58 ED |
1313 | if (ignore_snapdev == B_FALSE) { |
1314 | error = __zvol_snapdev_hidden(name); | |
1315 | if (error) | |
1316 | goto out; | |
1317 | } | |
1318 | ||
79c76d5b | 1319 | doi = kmem_alloc(sizeof (dmu_object_info_t), KM_SLEEP); |
60101509 BB |
1320 | |
1321 | error = dmu_objset_own(name, DMU_OST_ZVOL, B_TRUE, zvol_tag, &os); | |
1322 | if (error) | |
1323 | goto out_doi; | |
1324 | ||
1325 | error = dmu_object_info(os, ZVOL_OBJ, doi); | |
1326 | if (error) | |
1327 | goto out_dmu_objset_disown; | |
1328 | ||
1329 | error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize); | |
1330 | if (error) | |
1331 | goto out_dmu_objset_disown; | |
1332 | ||
1333 | error = zvol_find_minor(&minor); | |
1334 | if (error) | |
1335 | goto out_dmu_objset_disown; | |
1336 | ||
1337 | zv = zvol_alloc(MKDEV(zvol_major, minor), name); | |
1338 | if (zv == NULL) { | |
2e528b49 | 1339 | error = SET_ERROR(EAGAIN); |
60101509 BB |
1340 | goto out_dmu_objset_disown; |
1341 | } | |
1342 | ||
1343 | if (dmu_objset_is_snapshot(os)) | |
1344 | zv->zv_flags |= ZVOL_RDONLY; | |
1345 | ||
1346 | zv->zv_volblocksize = doi->doi_data_block_size; | |
1347 | zv->zv_volsize = volsize; | |
1348 | zv->zv_objset = os; | |
1349 | ||
1350 | set_capacity(zv->zv_disk, zv->zv_volsize >> 9); | |
1351 | ||
c495fe2c | 1352 | blk_queue_max_hw_sectors(zv->zv_queue, (DMU_MAX_ACCESS / 4) >> 9); |
34037afe ED |
1353 | blk_queue_max_segments(zv->zv_queue, UINT16_MAX); |
1354 | blk_queue_max_segment_size(zv->zv_queue, UINT_MAX); | |
1355 | blk_queue_physical_block_size(zv->zv_queue, zv->zv_volblocksize); | |
1356 | blk_queue_io_opt(zv->zv_queue, zv->zv_volblocksize); | |
7c0e5708 ED |
1357 | blk_queue_max_discard_sectors(zv->zv_queue, |
1358 | (zvol_max_discard_blocks * zv->zv_volblocksize) >> 9); | |
ee5fd0bb | 1359 | blk_queue_discard_granularity(zv->zv_queue, zv->zv_volblocksize); |
30930fba | 1360 | queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, zv->zv_queue); |
37f9dac5 | 1361 | #ifdef QUEUE_FLAG_NONROT |
34037afe ED |
1362 | queue_flag_set_unlocked(QUEUE_FLAG_NONROT, zv->zv_queue); |
1363 | #endif | |
c6a3a222 RY |
1364 | #ifdef QUEUE_FLAG_ADD_RANDOM |
1365 | queue_flag_clear_unlocked(QUEUE_FLAG_ADD_RANDOM, zv->zv_queue); | |
1366 | #endif | |
34037afe | 1367 | |
a4430fce GW |
1368 | if (spa_writeable(dmu_objset_spa(os))) { |
1369 | if (zil_replay_disable) | |
1370 | zil_destroy(dmu_objset_zil(os), B_FALSE); | |
1371 | else | |
1372 | zil_replay(os, zv, zvol_replay_vector); | |
1373 | } | |
60101509 | 1374 | |
9965059a BB |
1375 | /* |
1376 | * When udev detects the addition of the device it will immediately | |
1377 | * invoke blkid(8) to determine the type of content on the device. | |
1378 | * Prefetching the blocks commonly scanned by blkid(8) will speed | |
1379 | * up this process. | |
1380 | */ | |
1381 | len = MIN(MAX(zvol_prefetch_bytes, 0), SPA_MAXBLOCKSIZE); | |
1382 | if (len > 0) { | |
1383 | dmu_prefetch(os, ZVOL_OBJ, 0, len); | |
1384 | dmu_prefetch(os, ZVOL_OBJ, volsize - len, len); | |
1385 | } | |
1386 | ||
f74a147c | 1387 | zv->zv_objset = NULL; |
60101509 BB |
1388 | out_dmu_objset_disown: |
1389 | dmu_objset_disown(os, zvol_tag); | |
60101509 | 1390 | out_doi: |
ce37ebd2 | 1391 | kmem_free(doi, sizeof (dmu_object_info_t)); |
60101509 BB |
1392 | out: |
1393 | ||
1394 | if (error == 0) { | |
1395 | zvol_insert(zv); | |
1396 | add_disk(zv->zv_disk); | |
1397 | } | |
1398 | ||
ce37ebd2 | 1399 | return (SET_ERROR(error)); |
60101509 BB |
1400 | } |
1401 | ||
1402 | /* | |
1403 | * Create a block device minor node and setup the linkage between it | |
1404 | * and the specified volume. Once this function returns the block | |
1405 | * device is live and ready for use. | |
1406 | */ | |
1407 | int | |
1408 | zvol_create_minor(const char *name) | |
1409 | { | |
1410 | int error; | |
1411 | ||
1412 | mutex_enter(&zvol_state_lock); | |
0b4d1b58 | 1413 | error = __zvol_create_minor(name, B_FALSE); |
60101509 BB |
1414 | mutex_exit(&zvol_state_lock); |
1415 | ||
ce37ebd2 | 1416 | return (SET_ERROR(error)); |
60101509 BB |
1417 | } |
1418 | ||
1419 | static int | |
1420 | __zvol_remove_minor(const char *name) | |
1421 | { | |
1422 | zvol_state_t *zv; | |
1423 | ||
1424 | ASSERT(MUTEX_HELD(&zvol_state_lock)); | |
1425 | ||
1426 | zv = zvol_find_by_name(name); | |
1427 | if (zv == NULL) | |
2e528b49 | 1428 | return (SET_ERROR(ENXIO)); |
60101509 BB |
1429 | |
1430 | if (zv->zv_open_count > 0) | |
2e528b49 | 1431 | return (SET_ERROR(EBUSY)); |
60101509 BB |
1432 | |
1433 | zvol_remove(zv); | |
1434 | zvol_free(zv); | |
1435 | ||
1436 | return (0); | |
1437 | } | |
1438 | ||
1439 | /* | |
1440 | * Remove a block device minor node for the specified volume. | |
1441 | */ | |
1442 | int | |
1443 | zvol_remove_minor(const char *name) | |
1444 | { | |
1445 | int error; | |
1446 | ||
1447 | mutex_enter(&zvol_state_lock); | |
1448 | error = __zvol_remove_minor(name); | |
1449 | mutex_exit(&zvol_state_lock); | |
1450 | ||
ce37ebd2 | 1451 | return (SET_ERROR(error)); |
60101509 BB |
1452 | } |
1453 | ||
ba6a2402 BB |
1454 | /* |
1455 | * Rename a block device minor mode for the specified volume. | |
1456 | */ | |
1457 | static void | |
1458 | __zvol_rename_minor(zvol_state_t *zv, const char *newname) | |
1459 | { | |
1460 | int readonly = get_disk_ro(zv->zv_disk); | |
1461 | ||
1462 | ASSERT(MUTEX_HELD(&zvol_state_lock)); | |
1463 | ||
1464 | strlcpy(zv->zv_name, newname, sizeof (zv->zv_name)); | |
1465 | ||
1466 | /* | |
1467 | * The block device's read-only state is briefly changed causing | |
1468 | * a KOBJ_CHANGE uevent to be issued. This ensures udev detects | |
1469 | * the name change and fixes the symlinks. This does not change | |
1470 | * ZVOL_RDONLY in zv->zv_flags so the actual read-only state never | |
1471 | * changes. This would normally be done using kobject_uevent() but | |
1472 | * that is a GPL-only symbol which is why we need this workaround. | |
1473 | */ | |
1474 | set_disk_ro(zv->zv_disk, !readonly); | |
1475 | set_disk_ro(zv->zv_disk, readonly); | |
1476 | } | |
1477 | ||
60101509 | 1478 | static int |
13fe0198 | 1479 | zvol_create_minors_cb(const char *dsname, void *arg) |
60101509 | 1480 | { |
ba6a2402 | 1481 | (void) zvol_create_minor(dsname); |
60101509 | 1482 | |
d5674448 | 1483 | return (0); |
60101509 BB |
1484 | } |
1485 | ||
1486 | /* | |
ba6a2402 | 1487 | * Create minors for specified dataset including children and snapshots. |
60101509 BB |
1488 | */ |
1489 | int | |
ba6a2402 | 1490 | zvol_create_minors(const char *name) |
60101509 | 1491 | { |
60101509 BB |
1492 | int error = 0; |
1493 | ||
ba6a2402 BB |
1494 | if (!zvol_inhibit_dev) |
1495 | error = dmu_objset_find((char *)name, zvol_create_minors_cb, | |
1496 | NULL, DS_FIND_CHILDREN | DS_FIND_SNAPSHOTS); | |
1497 | ||
1498 | return (SET_ERROR(error)); | |
1499 | } | |
1500 | ||
1501 | /* | |
1502 | * Remove minors for specified dataset including children and snapshots. | |
1503 | */ | |
1504 | void | |
1505 | zvol_remove_minors(const char *name) | |
1506 | { | |
1507 | zvol_state_t *zv, *zv_next; | |
1508 | int namelen = ((name) ? strlen(name) : 0); | |
1509 | ||
74497b7a | 1510 | if (zvol_inhibit_dev) |
ba6a2402 | 1511 | return; |
74497b7a | 1512 | |
60101509 | 1513 | mutex_enter(&zvol_state_lock); |
ba6a2402 BB |
1514 | |
1515 | for (zv = list_head(&zvol_state_list); zv != NULL; zv = zv_next) { | |
1516 | zv_next = list_next(&zvol_state_list, zv); | |
1517 | ||
1518 | if (name == NULL || strcmp(zv->zv_name, name) == 0 || | |
1519 | (strncmp(zv->zv_name, name, namelen) == 0 && | |
1520 | zv->zv_name[namelen] == '/')) { | |
1521 | zvol_remove(zv); | |
1522 | zvol_free(zv); | |
60101509 | 1523 | } |
60101509 | 1524 | } |
60101509 | 1525 | |
ba6a2402 | 1526 | mutex_exit(&zvol_state_lock); |
60101509 BB |
1527 | } |
1528 | ||
1529 | /* | |
ba6a2402 | 1530 | * Rename minors for specified dataset including children and snapshots. |
60101509 BB |
1531 | */ |
1532 | void | |
ba6a2402 | 1533 | zvol_rename_minors(const char *oldname, const char *newname) |
60101509 BB |
1534 | { |
1535 | zvol_state_t *zv, *zv_next; | |
ba6a2402 BB |
1536 | int oldnamelen, newnamelen; |
1537 | char *name; | |
60101509 | 1538 | |
74497b7a DH |
1539 | if (zvol_inhibit_dev) |
1540 | return; | |
1541 | ||
ba6a2402 BB |
1542 | oldnamelen = strlen(oldname); |
1543 | newnamelen = strlen(newname); | |
79c76d5b | 1544 | name = kmem_alloc(MAXNAMELEN, KM_SLEEP); |
60101509 BB |
1545 | |
1546 | mutex_enter(&zvol_state_lock); | |
ba6a2402 | 1547 | |
60101509 BB |
1548 | for (zv = list_head(&zvol_state_list); zv != NULL; zv = zv_next) { |
1549 | zv_next = list_next(&zvol_state_list, zv); | |
1550 | ||
ba6a2402 BB |
1551 | if (strcmp(zv->zv_name, oldname) == 0) { |
1552 | __zvol_rename_minor(zv, newname); | |
1553 | } else if (strncmp(zv->zv_name, oldname, oldnamelen) == 0 && | |
1554 | (zv->zv_name[oldnamelen] == '/' || | |
1555 | zv->zv_name[oldnamelen] == '@')) { | |
1556 | snprintf(name, MAXNAMELEN, "%s%c%s", newname, | |
1557 | zv->zv_name[oldnamelen], | |
1558 | zv->zv_name + oldnamelen + 1); | |
1559 | __zvol_rename_minor(zv, name); | |
60101509 BB |
1560 | } |
1561 | } | |
ba6a2402 | 1562 | |
60101509 | 1563 | mutex_exit(&zvol_state_lock); |
ba6a2402 BB |
1564 | |
1565 | kmem_free(name, MAXNAMELEN); | |
60101509 BB |
1566 | } |
1567 | ||
0b4d1b58 ED |
1568 | static int |
1569 | snapdev_snapshot_changed_cb(const char *dsname, void *arg) { | |
1570 | uint64_t snapdev = *(uint64_t *) arg; | |
1571 | ||
1572 | if (strchr(dsname, '@') == NULL) | |
ba6a2402 | 1573 | return (0); |
0b4d1b58 ED |
1574 | |
1575 | switch (snapdev) { | |
1576 | case ZFS_SNAPDEV_VISIBLE: | |
1577 | mutex_enter(&zvol_state_lock); | |
1578 | (void) __zvol_create_minor(dsname, B_TRUE); | |
1579 | mutex_exit(&zvol_state_lock); | |
1580 | break; | |
1581 | case ZFS_SNAPDEV_HIDDEN: | |
1582 | (void) zvol_remove_minor(dsname); | |
1583 | break; | |
1584 | } | |
ba6a2402 BB |
1585 | |
1586 | return (0); | |
0b4d1b58 ED |
1587 | } |
1588 | ||
1589 | int | |
1590 | zvol_set_snapdev(const char *dsname, uint64_t snapdev) { | |
1591 | (void) dmu_objset_find((char *) dsname, snapdev_snapshot_changed_cb, | |
1592 | &snapdev, DS_FIND_SNAPSHOTS | DS_FIND_CHILDREN); | |
1593 | /* caller should continue to modify snapdev property */ | |
1594 | return (-1); | |
1595 | } | |
1596 | ||
60101509 BB |
1597 | int |
1598 | zvol_init(void) | |
1599 | { | |
1600 | int error; | |
1601 | ||
2a3871d4 | 1602 | list_create(&zvol_state_list, sizeof (zvol_state_t), |
ce37ebd2 BB |
1603 | offsetof(zvol_state_t, zv_next)); |
1604 | ||
2a3871d4 RY |
1605 | mutex_init(&zvol_state_lock, NULL, MUTEX_DEFAULT, NULL); |
1606 | ||
60101509 BB |
1607 | error = register_blkdev(zvol_major, ZVOL_DRIVER); |
1608 | if (error) { | |
1609 | printk(KERN_INFO "ZFS: register_blkdev() failed %d\n", error); | |
37f9dac5 | 1610 | goto out; |
60101509 BB |
1611 | } |
1612 | ||
1613 | blk_register_region(MKDEV(zvol_major, 0), 1UL << MINORBITS, | |
ce37ebd2 | 1614 | THIS_MODULE, zvol_probe, NULL, NULL); |
60101509 | 1615 | |
60101509 | 1616 | return (0); |
2a3871d4 | 1617 | |
37f9dac5 | 1618 | out: |
2a3871d4 RY |
1619 | mutex_destroy(&zvol_state_lock); |
1620 | list_destroy(&zvol_state_list); | |
1621 | ||
ce37ebd2 | 1622 | return (SET_ERROR(error)); |
60101509 BB |
1623 | } |
1624 | ||
1625 | void | |
1626 | zvol_fini(void) | |
1627 | { | |
1628 | zvol_remove_minors(NULL); | |
1629 | blk_unregister_region(MKDEV(zvol_major, 0), 1UL << MINORBITS); | |
1630 | unregister_blkdev(zvol_major, ZVOL_DRIVER); | |
60101509 BB |
1631 | mutex_destroy(&zvol_state_lock); |
1632 | list_destroy(&zvol_state_list); | |
1633 | } | |
1634 | ||
74497b7a DH |
1635 | module_param(zvol_inhibit_dev, uint, 0644); |
1636 | MODULE_PARM_DESC(zvol_inhibit_dev, "Do not create zvol device nodes"); | |
1637 | ||
30a9524e | 1638 | module_param(zvol_major, uint, 0444); |
60101509 BB |
1639 | MODULE_PARM_DESC(zvol_major, "Major number for zvol device"); |
1640 | ||
7c0e5708 | 1641 | module_param(zvol_max_discard_blocks, ulong, 0444); |
ce37ebd2 | 1642 | MODULE_PARM_DESC(zvol_max_discard_blocks, "Max number of blocks to discard"); |
9965059a BB |
1643 | |
1644 | module_param(zvol_prefetch_bytes, uint, 0644); | |
1645 | MODULE_PARM_DESC(zvol_prefetch_bytes, "Prefetch N bytes at zvol start+end"); |