1
2
3
4
5
6menuconfig MD
7 bool "Multiple devices driver support (RAID and LVM)"
8 depends on BLOCK
9 select SRCU
10 help
11 Support multiple physical spindles through a single logical device.
12 Required for RAID and logical volume management.
13
14if MD
15
16config BLK_DEV_MD
17 tristate "RAID support"
18 select BLOCK_HOLDER_DEPRECATED if SYSFS
19 help
20 This driver lets you combine several hard disk partitions into one
21 logical block device. This can be used to simply append one
22 partition to another one or to combine several redundant hard disks
23 into a RAID1/4/5 device so as to provide protection against hard
24 disk failures. This is called "Software RAID" since the combining of
25 the partitions is done by the kernel. "Hardware RAID" means that the
26 combining is done by a dedicated controller; if you have such a
27 controller, you do not need to say Y here.
28
29 More information about Software RAID on Linux is contained in the
30 Software RAID mini-HOWTO, available from
31 <https://www.tldp.org/docs.html#howto>. There you will also learn
32 where to get the supporting user space utilities raidtools.
33
34 If unsure, say N.
35
36config MD_AUTODETECT
37 bool "Autodetect RAID arrays during kernel boot"
38 depends on BLK_DEV_MD=y
39 default y
40 help
41 If you say Y here, then the kernel will try to autodetect raid
42 arrays as part of its boot process.
43
44 If you don't use raid and say Y, this autodetection can cause
45 a several-second delay in the boot time due to various
46 synchronisation steps that are part of this step.
47
48 If unsure, say Y.
49
50config MD_LINEAR
51 tristate "Linear (append) mode (deprecated)"
52 depends on BLK_DEV_MD
53 help
54 If you say Y here, then your multiple devices driver will be able to
55 use the so-called linear mode, i.e. it will combine the hard disk
56 partitions by simply appending one to the other.
57
58 To compile this as a module, choose M here: the module
59 will be called linear.
60
61 If unsure, say Y.
62
63config MD_RAID0
64 tristate "RAID-0 (striping) mode"
65 depends on BLK_DEV_MD
66 help
67 If you say Y here, then your multiple devices driver will be able to
68 use the so-called raid0 mode, i.e. it will combine the hard disk
69 partitions into one logical device in such a fashion as to fill them
70 up evenly, one chunk here and one chunk there. This will increase
71 the throughput rate if the partitions reside on distinct disks.
72
73 Information about Software RAID on Linux is contained in the
74 Software-RAID mini-HOWTO, available from
75 <https://www.tldp.org/docs.html#howto>. There you will also
76 learn where to get the supporting user space utilities raidtools.
77
78 To compile this as a module, choose M here: the module
79 will be called raid0.
80
81 If unsure, say Y.
82
83config MD_RAID1
84 tristate "RAID-1 (mirroring) mode"
85 depends on BLK_DEV_MD
86 help
87 A RAID-1 set consists of several disk drives which are exact copies
88 of each other. In the event of a mirror failure, the RAID driver
89 will continue to use the operational mirrors in the set, providing
90 an error free MD (multiple device) to the higher levels of the
91 kernel. In a set with N drives, the available space is the capacity
92 of a single drive, and the set protects against a failure of (N - 1)
93 drives.
94
95 Information about Software RAID on Linux is contained in the
96 Software-RAID mini-HOWTO, available from
97 <https://www.tldp.org/docs.html#howto>. There you will also
98 learn where to get the supporting user space utilities raidtools.
99
100 If you want to use such a RAID-1 set, say Y. To compile this code
101 as a module, choose M here: the module will be called raid1.
102
103 If unsure, say Y.
104
105config MD_RAID10
106 tristate "RAID-10 (mirrored striping) mode"
107 depends on BLK_DEV_MD
108 help
109 RAID-10 provides a combination of striping (RAID-0) and
110 mirroring (RAID-1) with easier configuration and more flexible
111 layout.
112 Unlike RAID-0, but like RAID-1, RAID-10 requires all devices to
113 be the same size (or at least, only as much as the smallest device
114 will be used).
115 RAID-10 provides a variety of layouts that provide different levels
116 of redundancy and performance.
117
118 RAID-10 requires mdadm-1.7.0 or later, available at:
119
120 https://www.kernel.org/pub/linux/utils/raid/mdadm/
121
122 If unsure, say Y.
123
124config MD_RAID456
125 tristate "RAID-4/RAID-5/RAID-6 mode"
126 depends on BLK_DEV_MD
127 select RAID6_PQ
128 select LIBCRC32C
129 select ASYNC_MEMCPY
130 select ASYNC_XOR
131 select ASYNC_PQ
132 select ASYNC_RAID6_RECOV
133 help
134 A RAID-5 set of N drives with a capacity of C MB per drive provides
135 the capacity of C * (N - 1) MB, and protects against a failure
136 of a single drive. For a given sector (row) number, (N - 1) drives
137 contain data sectors, and one drive contains the parity protection.
138 For a RAID-4 set, the parity blocks are present on a single drive,
139 while a RAID-5 set distributes the parity across the drives in one
140 of the available parity distribution methods.
141
142 A RAID-6 set of N drives with a capacity of C MB per drive
143 provides the capacity of C * (N - 2) MB, and protects
144 against a failure of any two drives. For a given sector
145 (row) number, (N - 2) drives contain data sectors, and two
146 drives contains two independent redundancy syndromes. Like
147 RAID-5, RAID-6 distributes the syndromes across the drives
148 in one of the available parity distribution methods.
149
150 Information about Software RAID on Linux is contained in the
151 Software-RAID mini-HOWTO, available from
152 <https://www.tldp.org/docs.html#howto>. There you will also
153 learn where to get the supporting user space utilities raidtools.
154
155 If you want to use such a RAID-4/RAID-5/RAID-6 set, say Y. To
156 compile this code as a module, choose M here: the module
157 will be called raid456.
158
159 If unsure, say Y.
160
161config MD_MULTIPATH
162 tristate "Multipath I/O support (deprecated)"
163 depends on BLK_DEV_MD
164 help
165 MD_MULTIPATH provides a simple multi-path personality for use
166 the MD framework. It is not under active development. New
167 projects should consider using DM_MULTIPATH which has more
168 features and more testing.
169
170 If unsure, say N.
171
172config MD_FAULTY
173 tristate "Faulty test module for MD (deprecated)"
174 depends on BLK_DEV_MD
175 help
176 The "faulty" module allows for a block device that occasionally returns
177 read or write errors. It is useful for testing.
178
179 In unsure, say N.
180
181
182config MD_CLUSTER
183 tristate "Cluster Support for MD"
184 depends on BLK_DEV_MD
185 depends on DLM
186 default n
187 help
188 Clustering support for MD devices. This enables locking and
189 synchronization across multiple systems on the cluster, so all
190 nodes in the cluster can access the MD devices simultaneously.
191
192 This brings the redundancy (and uptime) of RAID levels across the
193 nodes of the cluster. Currently, it can work with raid1 and raid10
194 (limited support).
195
196 If unsure, say N.
197
198source "drivers/md/bcache/Kconfig"
199
200config BLK_DEV_DM_BUILTIN
201 bool
202
203config BLK_DEV_DM
204 tristate "Device mapper support"
205 select BLOCK_HOLDER_DEPRECATED if SYSFS
206 select BLK_DEV_DM_BUILTIN
207 depends on DAX || DAX=n
208 help
209 Device-mapper is a low level volume manager. It works by allowing
210 people to specify mappings for ranges of logical sectors. Various
211 mapping types are available, in addition people may write their own
212 modules containing custom mappings if they wish.
213
214 Higher level volume managers such as LVM2 use this driver.
215
216 To compile this as a module, choose M here: the module will be
217 called dm-mod.
218
219 If unsure, say N.
220
221config DM_DEBUG
222 bool "Device mapper debugging support"
223 depends on BLK_DEV_DM
224 help
225 Enable this for messages that may help debug device-mapper problems.
226
227 If unsure, say N.
228
229config DM_BUFIO
230 tristate
231 depends on BLK_DEV_DM
232 help
233 This interface allows you to do buffered I/O on a device and acts
234 as a cache, holding recently-read blocks in memory and performing
235 delayed writes.
236
237config DM_DEBUG_BLOCK_MANAGER_LOCKING
238 bool "Block manager locking"
239 depends on DM_BUFIO
240 help
241 Block manager locking can catch various metadata corruption issues.
242
243 If unsure, say N.
244
245config DM_DEBUG_BLOCK_STACK_TRACING
246 bool "Keep stack trace of persistent data block lock holders"
247 depends on STACKTRACE_SUPPORT && DM_DEBUG_BLOCK_MANAGER_LOCKING
248 select STACKTRACE
249 help
250 Enable this for messages that may help debug problems with the
251 block manager locking used by thin provisioning and caching.
252
253 If unsure, say N.
254
255config DM_BIO_PRISON
256 tristate
257 depends on BLK_DEV_DM
258 help
259 Some bio locking schemes used by other device-mapper targets
260 including thin provisioning.
261
262source "drivers/md/persistent-data/Kconfig"
263
264config DM_UNSTRIPED
265 tristate "Unstriped target"
266 depends on BLK_DEV_DM
267 help
268 Unstripes I/O so it is issued solely on a single drive in a HW
269 RAID0 or dm-striped target.
270
271config DM_CRYPT
272 tristate "Crypt target support"
273 depends on BLK_DEV_DM
274 depends on (ENCRYPTED_KEYS || ENCRYPTED_KEYS=n)
275 depends on (TRUSTED_KEYS || TRUSTED_KEYS=n)
276 select CRYPTO
277 select CRYPTO_CBC
278 select CRYPTO_ESSIV
279 help
280 This device-mapper target allows you to create a device that
281 transparently encrypts the data on it. You'll need to activate
282 the ciphers you're going to use in the cryptoapi configuration.
283
284 For further information on dm-crypt and userspace tools see:
285 <https://gitlab.com/cryptsetup/cryptsetup/wikis/DMCrypt>
286
287 To compile this code as a module, choose M here: the module will
288 be called dm-crypt.
289
290 If unsure, say N.
291
292config DM_SNAPSHOT
293 tristate "Snapshot target"
294 depends on BLK_DEV_DM
295 select DM_BUFIO
296 help
297 Allow volume managers to take writable snapshots of a device.
298
299config DM_THIN_PROVISIONING
300 tristate "Thin provisioning target"
301 depends on BLK_DEV_DM
302 select DM_PERSISTENT_DATA
303 select DM_BIO_PRISON
304 help
305 Provides thin provisioning and snapshots that share a data store.
306
307config DM_CACHE
308 tristate "Cache target (EXPERIMENTAL)"
309 depends on BLK_DEV_DM
310 default n
311 select DM_PERSISTENT_DATA
312 select DM_BIO_PRISON
313 help
314 dm-cache attempts to improve performance of a block device by
315 moving frequently used data to a smaller, higher performance
316 device. Different 'policy' plugins can be used to change the
317 algorithms used to select which blocks are promoted, demoted,
318 cleaned etc. It supports writeback and writethrough modes.
319
320config DM_CACHE_SMQ
321 tristate "Stochastic MQ Cache Policy (EXPERIMENTAL)"
322 depends on DM_CACHE
323 default y
324 help
325 A cache policy that uses a multiqueue ordered by recent hits
326 to select which blocks should be promoted and demoted.
327 This is meant to be a general purpose policy. It prioritises
328 reads over writes. This SMQ policy (vs MQ) offers the promise
329 of less memory utilization, improved performance and increased
330 adaptability in the face of changing workloads.
331
332config DM_WRITECACHE
333 tristate "Writecache target"
334 depends on BLK_DEV_DM
335 help
336 The writecache target caches writes on persistent memory or SSD.
337 It is intended for databases or other programs that need extremely
338 low commit latency.
339
340 The writecache target doesn't cache reads because reads are supposed
341 to be cached in standard RAM.
342
343config DM_EBS
344 tristate "Emulated block size target (EXPERIMENTAL)"
345 depends on BLK_DEV_DM && !HIGHMEM
346 select DM_BUFIO
347 help
348 dm-ebs emulates smaller logical block size on backing devices
349 with larger ones (e.g. 512 byte sectors on 4K native disks).
350
351config DM_ERA
352 tristate "Era target (EXPERIMENTAL)"
353 depends on BLK_DEV_DM
354 default n
355 select DM_PERSISTENT_DATA
356 select DM_BIO_PRISON
357 help
358 dm-era tracks which parts of a block device are written to
359 over time. Useful for maintaining cache coherency when using
360 vendor snapshots.
361
362config DM_CLONE
363 tristate "Clone target (EXPERIMENTAL)"
364 depends on BLK_DEV_DM
365 default n
366 select DM_PERSISTENT_DATA
367 help
368 dm-clone produces a one-to-one copy of an existing, read-only source
369 device into a writable destination device. The cloned device is
370 visible/mountable immediately and the copy of the source device to the
371 destination device happens in the background, in parallel with user
372 I/O.
373
374 If unsure, say N.
375
376config DM_MIRROR
377 tristate "Mirror target"
378 depends on BLK_DEV_DM
379 help
380 Allow volume managers to mirror logical volumes, also
381 needed for live data migration tools such as 'pvmove'.
382
383config DM_LOG_USERSPACE
384 tristate "Mirror userspace logging"
385 depends on DM_MIRROR && NET
386 select CONNECTOR
387 help
388 The userspace logging module provides a mechanism for
389 relaying the dm-dirty-log API to userspace. Log designs
390 which are more suited to userspace implementation (e.g.
391 shared storage logs) or experimental logs can be implemented
392 by leveraging this framework.
393
394config DM_RAID
395 tristate "RAID 1/4/5/6/10 target"
396 depends on BLK_DEV_DM
397 select MD_RAID0
398 select MD_RAID1
399 select MD_RAID10
400 select MD_RAID456
401 select BLK_DEV_MD
402 help
403 A dm target that supports RAID1, RAID10, RAID4, RAID5 and RAID6 mappings
404
405 A RAID-5 set of N drives with a capacity of C MB per drive provides
406 the capacity of C * (N - 1) MB, and protects against a failure
407 of a single drive. For a given sector (row) number, (N - 1) drives
408 contain data sectors, and one drive contains the parity protection.
409 For a RAID-4 set, the parity blocks are present on a single drive,
410 while a RAID-5 set distributes the parity across the drives in one
411 of the available parity distribution methods.
412
413 A RAID-6 set of N drives with a capacity of C MB per drive
414 provides the capacity of C * (N - 2) MB, and protects
415 against a failure of any two drives. For a given sector
416 (row) number, (N - 2) drives contain data sectors, and two
417 drives contains two independent redundancy syndromes. Like
418 RAID-5, RAID-6 distributes the syndromes across the drives
419 in one of the available parity distribution methods.
420
421config DM_ZERO
422 tristate "Zero target"
423 depends on BLK_DEV_DM
424 help
425 A target that discards writes, and returns all zeroes for
426 reads. Useful in some recovery situations.
427
428config DM_MULTIPATH
429 tristate "Multipath target"
430 depends on BLK_DEV_DM
431
432
433
434
435 depends on !SCSI_DH || SCSI
436 help
437 Allow volume managers to support multipath hardware.
438
439config DM_MULTIPATH_QL
440 tristate "I/O Path Selector based on the number of in-flight I/Os"
441 depends on DM_MULTIPATH
442 help
443 This path selector is a dynamic load balancer which selects
444 the path with the least number of in-flight I/Os.
445
446 If unsure, say N.
447
448config DM_MULTIPATH_ST
449 tristate "I/O Path Selector based on the service time"
450 depends on DM_MULTIPATH
451 help
452 This path selector is a dynamic load balancer which selects
453 the path expected to complete the incoming I/O in the shortest
454 time.
455
456 If unsure, say N.
457
458config DM_MULTIPATH_HST
459 tristate "I/O Path Selector based on historical service time"
460 depends on DM_MULTIPATH
461 help
462 This path selector is a dynamic load balancer which selects
463 the path expected to complete the incoming I/O in the shortest
464 time by comparing estimated service time (based on historical
465 service time).
466
467 If unsure, say N.
468
469config DM_MULTIPATH_IOA
470 tristate "I/O Path Selector based on CPU submission"
471 depends on DM_MULTIPATH
472 help
473 This path selector selects the path based on the CPU the IO is
474 executed on and the CPU to path mapping setup at path addition time.
475
476 If unsure, say N.
477
478config DM_DELAY
479 tristate "I/O delaying target"
480 depends on BLK_DEV_DM
481 help
482 A target that delays reads and/or writes and can send
483 them to different devices. Useful for testing.
484
485 If unsure, say N.
486
487config DM_DUST
488 tristate "Bad sector simulation target"
489 depends on BLK_DEV_DM
490 help
491 A target that simulates bad sector behavior.
492 Useful for testing.
493
494 If unsure, say N.
495
496config DM_INIT
497 bool "DM \"dm-mod.create=\" parameter support"
498 depends on BLK_DEV_DM=y
499 help
500 Enable "dm-mod.create=" parameter to create mapped devices at init time.
501 This option is useful to allow mounting rootfs without requiring an
502 initramfs.
503 See Documentation/admin-guide/device-mapper/dm-init.rst for dm-mod.create="..."
504 format.
505
506 If unsure, say N.
507
508config DM_UEVENT
509 bool "DM uevents"
510 depends on BLK_DEV_DM
511 help
512 Generate udev events for DM events.
513
514config DM_FLAKEY
515 tristate "Flakey target"
516 depends on BLK_DEV_DM
517 help
518 A target that intermittently fails I/O for debugging purposes.
519
520config DM_VERITY
521 tristate "Verity target support"
522 depends on BLK_DEV_DM
523 select CRYPTO
524 select CRYPTO_HASH
525 select DM_BUFIO
526 help
527 This device-mapper target creates a read-only device that
528 transparently validates the data on one underlying device against
529 a pre-generated tree of cryptographic checksums stored on a second
530 device.
531
532 You'll need to activate the digests you're going to use in the
533 cryptoapi configuration.
534
535 To compile this code as a module, choose M here: the module will
536 be called dm-verity.
537
538 If unsure, say N.
539
540config DM_VERITY_VERIFY_ROOTHASH_SIG
541 def_bool n
542 bool "Verity data device root hash signature verification support"
543 depends on DM_VERITY
544 select SYSTEM_DATA_VERIFICATION
545 help
546 Add ability for dm-verity device to be validated if the
547 pre-generated tree of cryptographic checksums passed has a pkcs#7
548 signature file that can validate the roothash of the tree.
549
550 By default, rely on the builtin trusted keyring.
551
552 If unsure, say N.
553
554config DM_VERITY_VERIFY_ROOTHASH_SIG_SECONDARY_KEYRING
555 bool "Verity data device root hash signature verification with secondary keyring"
556 depends on DM_VERITY_VERIFY_ROOTHASH_SIG
557 depends on SECONDARY_TRUSTED_KEYRING
558 help
559 Rely on the secondary trusted keyring to verify dm-verity signatures.
560
561 If unsure, say N.
562
563config DM_VERITY_FEC
564 bool "Verity forward error correction support"
565 depends on DM_VERITY
566 select REED_SOLOMON
567 select REED_SOLOMON_DEC8
568 help
569 Add forward error correction support to dm-verity. This option
570 makes it possible to use pre-generated error correction data to
571 recover from corrupted blocks.
572
573 If unsure, say N.
574
575config DM_SWITCH
576 tristate "Switch target support (EXPERIMENTAL)"
577 depends on BLK_DEV_DM
578 help
579 This device-mapper target creates a device that supports an arbitrary
580 mapping of fixed-size regions of I/O across a fixed set of paths.
581 The path used for any specific region can be switched dynamically
582 by sending the target a message.
583
584 To compile this code as a module, choose M here: the module will
585 be called dm-switch.
586
587 If unsure, say N.
588
589config DM_LOG_WRITES
590 tristate "Log writes target support"
591 depends on BLK_DEV_DM
592 help
593 This device-mapper target takes two devices, one device to use
594 normally, one to log all write operations done to the first device.
595 This is for use by file system developers wishing to verify that
596 their fs is writing a consistent file system at all times by allowing
597 them to replay the log in a variety of ways and to check the
598 contents.
599
600 To compile this code as a module, choose M here: the module will
601 be called dm-log-writes.
602
603 If unsure, say N.
604
605config DM_INTEGRITY
606 tristate "Integrity target support"
607 depends on BLK_DEV_DM
608 select BLK_DEV_INTEGRITY
609 select DM_BUFIO
610 select CRYPTO
611 select CRYPTO_SKCIPHER
612 select ASYNC_XOR
613 help
614 This device-mapper target emulates a block device that has
615 additional per-sector tags that can be used for storing
616 integrity information.
617
618 This integrity target is used with the dm-crypt target to
619 provide authenticated disk encryption or it can be used
620 standalone.
621
622 To compile this code as a module, choose M here: the module will
623 be called dm-integrity.
624
625config DM_ZONED
626 tristate "Drive-managed zoned block device target support"
627 depends on BLK_DEV_DM
628 depends on BLK_DEV_ZONED
629 select CRC32
630 help
631 This device-mapper target takes a host-managed or host-aware zoned
632 block device and exposes most of its capacity as a regular block
633 device (drive-managed zoned block device) without any write
634 constraints. This is mainly intended for use with file systems that
635 do not natively support zoned block devices but still want to
636 benefit from the increased capacity offered by SMR disks. Other uses
637 by applications using raw block devices (for example object stores)
638 are also possible.
639
640 To compile this code as a module, choose M here: the module will
641 be called dm-zoned.
642
643 If unsure, say N.
644
645endif
646
