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1# SPDX-License-Identifier: GPL-2.0-only
2#
3# Block device driver configuration
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 help
19 This driver lets you combine several hard disk partitions into one
20 logical block device. This can be used to simply append one
21 partition to another one or to combine several redundant hard disks
22 into a RAID1/4/5 device so as to provide protection against hard
23 disk failures. This is called "Software RAID" since the combining of
24 the partitions is done by the kernel. "Hardware RAID" means that the
25 combining is done by a dedicated controller; if you have such a
26 controller, you do not need to say Y here.
27
28 More information about Software RAID on Linux is contained in the
29 Software RAID mini-HOWTO, available from
30 <https://www.tldp.org/docs.html#howto>. There you will also learn
31 where to get the supporting user space utilities raidtools.
32
33 If unsure, say N.
34
35config MD_AUTODETECT
36 bool "Autodetect RAID arrays during kernel boot"
37 depends on BLK_DEV_MD=y
38 default y
39 help
40 If you say Y here, then the kernel will try to autodetect raid
41 arrays as part of its boot process.
42
43 If you don't use raid and say Y, this autodetection can cause
44 a several-second delay in the boot time due to various
45 synchronisation steps that are part of this step.
46
47 If unsure, say Y.
48
49config MD_LINEAR
50 tristate "Linear (append) mode"
51 depends on BLK_DEV_MD
52 help
53 If you say Y here, then your multiple devices driver will be able to
54 use the so-called linear mode, i.e. it will combine the hard disk
55 partitions by simply appending one to the other.
56
57 To compile this as a module, choose M here: the module
58 will be called linear.
59
60 If unsure, say Y.
61
62config MD_RAID0
63 tristate "RAID-0 (striping) mode"
64 depends on BLK_DEV_MD
65 help
66 If you say Y here, then your multiple devices driver will be able to
67 use the so-called raid0 mode, i.e. it will combine the hard disk
68 partitions into one logical device in such a fashion as to fill them
69 up evenly, one chunk here and one chunk there. This will increase
70 the throughput rate if the partitions reside on distinct disks.
71
72 Information about Software RAID on Linux is contained in the
73 Software-RAID mini-HOWTO, available from
74 <https://www.tldp.org/docs.html#howto>. There you will also
75 learn where to get the supporting user space utilities raidtools.
76
77 To compile this as a module, choose M here: the module
78 will be called raid0.
79
80 If unsure, say Y.
81
82config MD_RAID1
83 tristate "RAID-1 (mirroring) mode"
84 depends on BLK_DEV_MD
85 help
86 A RAID-1 set consists of several disk drives which are exact copies
87 of each other. In the event of a mirror failure, the RAID driver
88 will continue to use the operational mirrors in the set, providing
89 an error free MD (multiple device) to the higher levels of the
90 kernel. In a set with N drives, the available space is the capacity
91 of a single drive, and the set protects against a failure of (N - 1)
92 drives.
93
94 Information about Software RAID on Linux is contained in the
95 Software-RAID mini-HOWTO, available from
96 <https://www.tldp.org/docs.html#howto>. There you will also
97 learn where to get the supporting user space utilities raidtools.
98
99 If you want to use such a RAID-1 set, say Y. To compile this code
100 as a module, choose M here: the module will be called raid1.
101
102 If unsure, say Y.
103
104config MD_RAID10
105 tristate "RAID-10 (mirrored striping) mode"
106 depends on BLK_DEV_MD
107 help
108 RAID-10 provides a combination of striping (RAID-0) and
109 mirroring (RAID-1) with easier configuration and more flexible
110 layout.
111 Unlike RAID-0, but like RAID-1, RAID-10 requires all devices to
112 be the same size (or at least, only as much as the smallest device
113 will be used).
114 RAID-10 provides a variety of layouts that provide different levels
115 of redundancy and performance.
116
117 RAID-10 requires mdadm-1.7.0 or later, available at:
118
119 https://www.kernel.org/pub/linux/utils/raid/mdadm/
120
121 If unsure, say Y.
122
123config MD_RAID456
124 tristate "RAID-4/RAID-5/RAID-6 mode"
125 depends on BLK_DEV_MD
126 select RAID6_PQ
127 select LIBCRC32C
128 select ASYNC_MEMCPY
129 select ASYNC_XOR
130 select ASYNC_PQ
131 select ASYNC_RAID6_RECOV
132 help
133 A RAID-5 set of N drives with a capacity of C MB per drive provides
134 the capacity of C * (N - 1) MB, and protects against a failure
135 of a single drive. For a given sector (row) number, (N - 1) drives
136 contain data sectors, and one drive contains the parity protection.
137 For a RAID-4 set, the parity blocks are present on a single drive,
138 while a RAID-5 set distributes the parity across the drives in one
139 of the available parity distribution methods.
140
141 A RAID-6 set of N drives with a capacity of C MB per drive
142 provides the capacity of C * (N - 2) MB, and protects
143 against a failure of any two drives. For a given sector
144 (row) number, (N - 2) drives contain data sectors, and two
145 drives contains two independent redundancy syndromes. Like
146 RAID-5, RAID-6 distributes the syndromes across the drives
147 in one of the available parity distribution methods.
148
149 Information about Software RAID on Linux is contained in the
150 Software-RAID mini-HOWTO, available from
151 <https://www.tldp.org/docs.html#howto>. There you will also
152 learn where to get the supporting user space utilities raidtools.
153
154 If you want to use such a RAID-4/RAID-5/RAID-6 set, say Y. To
155 compile this code as a module, choose M here: the module
156 will be called raid456.
157
158 If unsure, say Y.
159
160config MD_MULTIPATH
161 tristate "Multipath I/O support"
162 depends on BLK_DEV_MD
163 help
164 MD_MULTIPATH provides a simple multi-path personality for use
165 the MD framework. It is not under active development. New
166 projects should consider using DM_MULTIPATH which has more
167 features and more testing.
168
169 If unsure, say N.
170
171config MD_FAULTY
172 tristate "Faulty test module for MD"
173 depends on BLK_DEV_MD
174 help
175 The "faulty" module allows for a block device that occasionally returns
176 read or write errors. It is useful for testing.
177
178 In unsure, say N.
179
180
181config MD_CLUSTER
182 tristate "Cluster Support for MD"
183 depends on BLK_DEV_MD
184 depends on DLM
185 default n
186 help
187 Clustering support for MD devices. This enables locking and
188 synchronization across multiple systems on the cluster, so all
189 nodes in the cluster can access the MD devices simultaneously.
190
191 This brings the redundancy (and uptime) of RAID levels across the
192 nodes of the cluster. Currently, it can work with raid1 and raid10
193 (limited support).
194
195 If unsure, say N.
196
197source "drivers/md/bcache/Kconfig"
198
199config BLK_DEV_DM_BUILTIN
200 bool
201
202config BLK_DEV_DM
203 tristate "Device mapper support"
204 select BLK_DEV_DM_BUILTIN
205 depends on DAX || DAX=n
206 help
207 Device-mapper is a low level volume manager. It works by allowing
208 people to specify mappings for ranges of logical sectors. Various
209 mapping types are available, in addition people may write their own
210 modules containing custom mappings if they wish.
211
212 Higher level volume managers such as LVM2 use this driver.
213
214 To compile this as a module, choose M here: the module will be
215 called dm-mod.
216
217 If unsure, say N.
218
219config DM_DEBUG
220 bool "Device mapper debugging support"
221 depends on BLK_DEV_DM
222 help
223 Enable this for messages that may help debug device-mapper problems.
224
225 If unsure, say N.
226
227config DM_BUFIO
228 tristate
229 depends on BLK_DEV_DM
230 help
231 This interface allows you to do buffered I/O on a device and acts
232 as a cache, holding recently-read blocks in memory and performing
233 delayed writes.
234
235config DM_DEBUG_BLOCK_MANAGER_LOCKING
236 bool "Block manager locking"
237 depends on DM_BUFIO
238 help
239 Block manager locking can catch various metadata corruption issues.
240
241 If unsure, say N.
242
243config DM_DEBUG_BLOCK_STACK_TRACING
244 bool "Keep stack trace of persistent data block lock holders"
245 depends on STACKTRACE_SUPPORT && DM_DEBUG_BLOCK_MANAGER_LOCKING
246 select STACKTRACE
247 help
248 Enable this for messages that may help debug problems with the
249 block manager locking used by thin provisioning and caching.
250
251 If unsure, say N.
252
253config DM_BIO_PRISON
254 tristate
255 depends on BLK_DEV_DM
256 help
257 Some bio locking schemes used by other device-mapper targets
258 including thin provisioning.
259
260source "drivers/md/persistent-data/Kconfig"
261
262config DM_UNSTRIPED
263 tristate "Unstriped target"
264 depends on BLK_DEV_DM
265 help
266 Unstripes I/O so it is issued solely on a single drive in a HW
267 RAID0 or dm-striped target.
268
269config DM_CRYPT
270 tristate "Crypt target support"
271 depends on BLK_DEV_DM
272 depends on (ENCRYPTED_KEYS || ENCRYPTED_KEYS=n)
273 select CRYPTO
274 select CRYPTO_CBC
275 select CRYPTO_ESSIV
276 help
277 This device-mapper target allows you to create a device that
278 transparently encrypts the data on it. You'll need to activate
279 the ciphers you're going to use in the cryptoapi configuration.
280
281 For further information on dm-crypt and userspace tools see:
282 <https://gitlab.com/cryptsetup/cryptsetup/wikis/DMCrypt>
283
284 To compile this code as a module, choose M here: the module will
285 be called dm-crypt.
286
287 If unsure, say N.
288
289config DM_SNAPSHOT
290 tristate "Snapshot target"
291 depends on BLK_DEV_DM
292 select DM_BUFIO
293 help
294 Allow volume managers to take writable snapshots of a device.
295
296config DM_THIN_PROVISIONING
297 tristate "Thin provisioning target"
298 depends on BLK_DEV_DM
299 select DM_PERSISTENT_DATA
300 select DM_BIO_PRISON
301 help
302 Provides thin provisioning and snapshots that share a data store.
303
304config DM_CACHE
305 tristate "Cache target (EXPERIMENTAL)"
306 depends on BLK_DEV_DM
307 default n
308 select DM_PERSISTENT_DATA
309 select DM_BIO_PRISON
310 help
311 dm-cache attempts to improve performance of a block device by
312 moving frequently used data to a smaller, higher performance
313 device. Different 'policy' plugins can be used to change the
314 algorithms used to select which blocks are promoted, demoted,
315 cleaned etc. It supports writeback and writethrough modes.
316
317config DM_CACHE_SMQ
318 tristate "Stochastic MQ Cache Policy (EXPERIMENTAL)"
319 depends on DM_CACHE
320 default y
321 help
322 A cache policy that uses a multiqueue ordered by recent hits
323 to select which blocks should be promoted and demoted.
324 This is meant to be a general purpose policy. It prioritises
325 reads over writes. This SMQ policy (vs MQ) offers the promise
326 of less memory utilization, improved performance and increased
327 adaptability in the face of changing workloads.
328
329config DM_WRITECACHE
330 tristate "Writecache target"
331 depends on BLK_DEV_DM
332 help
333 The writecache target caches writes on persistent memory or SSD.
334 It is intended for databases or other programs that need extremely
335 low commit latency.
336
337 The writecache target doesn't cache reads because reads are supposed
338 to be cached in standard RAM.
339
340config DM_EBS
341 tristate "Emulated block size target (EXPERIMENTAL)"
342 depends on BLK_DEV_DM
343 select DM_BUFIO
344 help
345 dm-ebs emulates smaller logical block size on backing devices
346 with larger ones (e.g. 512 byte sectors on 4K native disks).
347
348config DM_ERA
349 tristate "Era target (EXPERIMENTAL)"
350 depends on BLK_DEV_DM
351 default n
352 select DM_PERSISTENT_DATA
353 select DM_BIO_PRISON
354 help
355 dm-era tracks which parts of a block device are written to
356 over time. Useful for maintaining cache coherency when using
357 vendor snapshots.
358
359config DM_CLONE
360 tristate "Clone target (EXPERIMENTAL)"
361 depends on BLK_DEV_DM
362 default n
363 select DM_PERSISTENT_DATA
364 help
365 dm-clone produces a one-to-one copy of an existing, read-only source
366 device into a writable destination device. The cloned device is
367 visible/mountable immediately and the copy of the source device to the
368 destination device happens in the background, in parallel with user
369 I/O.
370
371 If unsure, say N.
372
373config DM_MIRROR
374 tristate "Mirror target"
375 depends on BLK_DEV_DM
376 help
377 Allow volume managers to mirror logical volumes, also
378 needed for live data migration tools such as 'pvmove'.
379
380config DM_LOG_USERSPACE
381 tristate "Mirror userspace logging"
382 depends on DM_MIRROR && NET
383 select CONNECTOR
384 help
385 The userspace logging module provides a mechanism for
386 relaying the dm-dirty-log API to userspace. Log designs
387 which are more suited to userspace implementation (e.g.
388 shared storage logs) or experimental logs can be implemented
389 by leveraging this framework.
390
391config DM_RAID
392 tristate "RAID 1/4/5/6/10 target"
393 depends on BLK_DEV_DM
394 select MD_RAID0
395 select MD_RAID1
396 select MD_RAID10
397 select MD_RAID456
398 select BLK_DEV_MD
399 help
400 A dm target that supports RAID1, RAID10, RAID4, RAID5 and RAID6 mappings
401
402 A RAID-5 set of N drives with a capacity of C MB per drive provides
403 the capacity of C * (N - 1) MB, and protects against a failure
404 of a single drive. For a given sector (row) number, (N - 1) drives
405 contain data sectors, and one drive contains the parity protection.
406 For a RAID-4 set, the parity blocks are present on a single drive,
407 while a RAID-5 set distributes the parity across the drives in one
408 of the available parity distribution methods.
409
410 A RAID-6 set of N drives with a capacity of C MB per drive
411 provides the capacity of C * (N - 2) MB, and protects
412 against a failure of any two drives. For a given sector
413 (row) number, (N - 2) drives contain data sectors, and two
414 drives contains two independent redundancy syndromes. Like
415 RAID-5, RAID-6 distributes the syndromes across the drives
416 in one of the available parity distribution methods.
417
418config DM_ZERO
419 tristate "Zero target"
420 depends on BLK_DEV_DM
421 help
422 A target that discards writes, and returns all zeroes for
423 reads. Useful in some recovery situations.
424
425config DM_MULTIPATH
426 tristate "Multipath target"
427 depends on BLK_DEV_DM
428 # nasty syntax but means make DM_MULTIPATH independent
429 # of SCSI_DH if the latter isn't defined but if
430 # it is, DM_MULTIPATH must depend on it. We get a build
431 # error if SCSI_DH=m and DM_MULTIPATH=y
432 depends on !SCSI_DH || SCSI
433 help
434 Allow volume managers to support multipath hardware.
435
436config DM_MULTIPATH_QL
437 tristate "I/O Path Selector based on the number of in-flight I/Os"
438 depends on DM_MULTIPATH
439 help
440 This path selector is a dynamic load balancer which selects
441 the path with the least number of in-flight I/Os.
442
443 If unsure, say N.
444
445config DM_MULTIPATH_ST
446 tristate "I/O Path Selector based on the service time"
447 depends on DM_MULTIPATH
448 help
449 This path selector is a dynamic load balancer which selects
450 the path expected to complete the incoming I/O in the shortest
451 time.
452
453 If unsure, say N.
454
455config DM_MULTIPATH_HST
456 tristate "I/O Path Selector based on historical service time"
457 depends on DM_MULTIPATH
458 help
459 This path selector is a dynamic load balancer which selects
460 the path expected to complete the incoming I/O in the shortest
461 time by comparing estimated service time (based on historical
462 service time).
463
464 If unsure, say N.
465
466config DM_DELAY
467 tristate "I/O delaying target"
468 depends on BLK_DEV_DM
469 help
470 A target that delays reads and/or writes and can send
471 them to different devices. Useful for testing.
472
473 If unsure, say N.
474
475config DM_DUST
476 tristate "Bad sector simulation target"
477 depends on BLK_DEV_DM
478 help
479 A target that simulates bad sector behavior.
480 Useful for testing.
481
482 If unsure, say N.
483
484config DM_INIT
485 bool "DM \"dm-mod.create=\" parameter support"
486 depends on BLK_DEV_DM=y
487 help
488 Enable "dm-mod.create=" parameter to create mapped devices at init time.
489 This option is useful to allow mounting rootfs without requiring an
490 initramfs.
491 See Documentation/admin-guide/device-mapper/dm-init.rst for dm-mod.create="..."
492 format.
493
494 If unsure, say N.
495
496config DM_UEVENT
497 bool "DM uevents"
498 depends on BLK_DEV_DM
499 help
500 Generate udev events for DM events.
501
502config DM_FLAKEY
503 tristate "Flakey target"
504 depends on BLK_DEV_DM
505 help
506 A target that intermittently fails I/O for debugging purposes.
507
508config DM_VERITY
509 tristate "Verity target support"
510 depends on BLK_DEV_DM
511 select CRYPTO
512 select CRYPTO_HASH
513 select DM_BUFIO
514 help
515 This device-mapper target creates a read-only device that
516 transparently validates the data on one underlying device against
517 a pre-generated tree of cryptographic checksums stored on a second
518 device.
519
520 You'll need to activate the digests you're going to use in the
521 cryptoapi configuration.
522
523 To compile this code as a module, choose M here: the module will
524 be called dm-verity.
525
526 If unsure, say N.
527
528config DM_VERITY_VERIFY_ROOTHASH_SIG
529 def_bool n
530 bool "Verity data device root hash signature verification support"
531 depends on DM_VERITY
532 select SYSTEM_DATA_VERIFICATION
533 help
534 Add ability for dm-verity device to be validated if the
535 pre-generated tree of cryptographic checksums passed has a pkcs#7
536 signature file that can validate the roothash of the tree.
537
538 If unsure, say N.
539
540config DM_VERITY_FEC
541 bool "Verity forward error correction support"
542 depends on DM_VERITY
543 select REED_SOLOMON
544 select REED_SOLOMON_DEC8
545 help
546 Add forward error correction support to dm-verity. This option
547 makes it possible to use pre-generated error correction data to
548 recover from corrupted blocks.
549
550 If unsure, say N.
551
552config DM_SWITCH
553 tristate "Switch target support (EXPERIMENTAL)"
554 depends on BLK_DEV_DM
555 help
556 This device-mapper target creates a device that supports an arbitrary
557 mapping of fixed-size regions of I/O across a fixed set of paths.
558 The path used for any specific region can be switched dynamically
559 by sending the target a message.
560
561 To compile this code as a module, choose M here: the module will
562 be called dm-switch.
563
564 If unsure, say N.
565
566config DM_LOG_WRITES
567 tristate "Log writes target support"
568 depends on BLK_DEV_DM
569 help
570 This device-mapper target takes two devices, one device to use
571 normally, one to log all write operations done to the first device.
572 This is for use by file system developers wishing to verify that
573 their fs is writing a consistent file system at all times by allowing
574 them to replay the log in a variety of ways and to check the
575 contents.
576
577 To compile this code as a module, choose M here: the module will
578 be called dm-log-writes.
579
580 If unsure, say N.
581
582config DM_INTEGRITY
583 tristate "Integrity target support"
584 depends on BLK_DEV_DM
585 select BLK_DEV_INTEGRITY
586 select DM_BUFIO
587 select CRYPTO
588 select ASYNC_XOR
589 help
590 This device-mapper target emulates a block device that has
591 additional per-sector tags that can be used for storing
592 integrity information.
593
594 This integrity target is used with the dm-crypt target to
595 provide authenticated disk encryption or it can be used
596 standalone.
597
598 To compile this code as a module, choose M here: the module will
599 be called dm-integrity.
600
601config DM_ZONED
602 tristate "Drive-managed zoned block device target support"
603 depends on BLK_DEV_DM
604 depends on BLK_DEV_ZONED
605 help
606 This device-mapper target takes a host-managed or host-aware zoned
607 block device and exposes most of its capacity as a regular block
608 device (drive-managed zoned block device) without any write
609 constraints. This is mainly intended for use with file systems that
610 do not natively support zoned block devices but still want to
611 benefit from the increased capacity offered by SMR disks. Other uses
612 by applications using raw block devices (for example object stores)
613 are also possible.
614
615 To compile this code as a module, choose M here: the module will
616 be called dm-zoned.
617
618 If unsure, say N.
619
620endif # MD
1#
2# Block device driver configuration
3#
4
5menuconfig MD
6 bool "Multiple devices driver support (RAID and LVM)"
7 depends on BLOCK
8 select SRCU
9 help
10 Support multiple physical spindles through a single logical device.
11 Required for RAID and logical volume management.
12
13if MD
14
15config BLK_DEV_MD
16 tristate "RAID support"
17 ---help---
18 This driver lets you combine several hard disk partitions into one
19 logical block device. This can be used to simply append one
20 partition to another one or to combine several redundant hard disks
21 into a RAID1/4/5 device so as to provide protection against hard
22 disk failures. This is called "Software RAID" since the combining of
23 the partitions is done by the kernel. "Hardware RAID" means that the
24 combining is done by a dedicated controller; if you have such a
25 controller, you do not need to say Y here.
26
27 More information about Software RAID on Linux is contained in the
28 Software RAID mini-HOWTO, available from
29 <http://www.tldp.org/docs.html#howto>. There you will also learn
30 where to get the supporting user space utilities raidtools.
31
32 If unsure, say N.
33
34config MD_AUTODETECT
35 bool "Autodetect RAID arrays during kernel boot"
36 depends on BLK_DEV_MD=y
37 default y
38 ---help---
39 If you say Y here, then the kernel will try to autodetect raid
40 arrays as part of its boot process.
41
42 If you don't use raid and say Y, this autodetection can cause
43 a several-second delay in the boot time due to various
44 synchronisation steps that are part of this step.
45
46 If unsure, say Y.
47
48config MD_LINEAR
49 tristate "Linear (append) mode"
50 depends on BLK_DEV_MD
51 ---help---
52 If you say Y here, then your multiple devices driver will be able to
53 use the so-called linear mode, i.e. it will combine the hard disk
54 partitions by simply appending one to the other.
55
56 To compile this as a module, choose M here: the module
57 will be called linear.
58
59 If unsure, say Y.
60
61config MD_RAID0
62 tristate "RAID-0 (striping) mode"
63 depends on BLK_DEV_MD
64 ---help---
65 If you say Y here, then your multiple devices driver will be able to
66 use the so-called raid0 mode, i.e. it will combine the hard disk
67 partitions into one logical device in such a fashion as to fill them
68 up evenly, one chunk here and one chunk there. This will increase
69 the throughput rate if the partitions reside on distinct disks.
70
71 Information about Software RAID on Linux is contained in the
72 Software-RAID mini-HOWTO, available from
73 <http://www.tldp.org/docs.html#howto>. There you will also
74 learn where to get the supporting user space utilities raidtools.
75
76 To compile this as a module, choose M here: the module
77 will be called raid0.
78
79 If unsure, say Y.
80
81config MD_RAID1
82 tristate "RAID-1 (mirroring) mode"
83 depends on BLK_DEV_MD
84 ---help---
85 A RAID-1 set consists of several disk drives which are exact copies
86 of each other. In the event of a mirror failure, the RAID driver
87 will continue to use the operational mirrors in the set, providing
88 an error free MD (multiple device) to the higher levels of the
89 kernel. In a set with N drives, the available space is the capacity
90 of a single drive, and the set protects against a failure of (N - 1)
91 drives.
92
93 Information about Software RAID on Linux is contained in the
94 Software-RAID mini-HOWTO, available from
95 <http://www.tldp.org/docs.html#howto>. There you will also
96 learn where to get the supporting user space utilities raidtools.
97
98 If you want to use such a RAID-1 set, say Y. To compile this code
99 as a module, choose M here: the module will be called raid1.
100
101 If unsure, say Y.
102
103config MD_RAID10
104 tristate "RAID-10 (mirrored striping) mode"
105 depends on BLK_DEV_MD
106 ---help---
107 RAID-10 provides a combination of striping (RAID-0) and
108 mirroring (RAID-1) with easier configuration and more flexible
109 layout.
110 Unlike RAID-0, but like RAID-1, RAID-10 requires all devices to
111 be the same size (or at least, only as much as the smallest device
112 will be used).
113 RAID-10 provides a variety of layouts that provide different levels
114 of redundancy and performance.
115
116 RAID-10 requires mdadm-1.7.0 or later, available at:
117
118 ftp://ftp.kernel.org/pub/linux/utils/raid/mdadm/
119
120 If unsure, say Y.
121
122config MD_RAID456
123 tristate "RAID-4/RAID-5/RAID-6 mode"
124 depends on BLK_DEV_MD
125 select RAID6_PQ
126 select LIBCRC32C
127 select ASYNC_MEMCPY
128 select ASYNC_XOR
129 select ASYNC_PQ
130 select ASYNC_RAID6_RECOV
131 ---help---
132 A RAID-5 set of N drives with a capacity of C MB per drive provides
133 the capacity of C * (N - 1) MB, and protects against a failure
134 of a single drive. For a given sector (row) number, (N - 1) drives
135 contain data sectors, and one drive contains the parity protection.
136 For a RAID-4 set, the parity blocks are present on a single drive,
137 while a RAID-5 set distributes the parity across the drives in one
138 of the available parity distribution methods.
139
140 A RAID-6 set of N drives with a capacity of C MB per drive
141 provides the capacity of C * (N - 2) MB, and protects
142 against a failure of any two drives. For a given sector
143 (row) number, (N - 2) drives contain data sectors, and two
144 drives contains two independent redundancy syndromes. Like
145 RAID-5, RAID-6 distributes the syndromes across the drives
146 in one of the available parity distribution methods.
147
148 Information about Software RAID on Linux is contained in the
149 Software-RAID mini-HOWTO, available from
150 <http://www.tldp.org/docs.html#howto>. There you will also
151 learn where to get the supporting user space utilities raidtools.
152
153 If you want to use such a RAID-4/RAID-5/RAID-6 set, say Y. To
154 compile this code as a module, choose M here: the module
155 will be called raid456.
156
157 If unsure, say Y.
158
159config MD_MULTIPATH
160 tristate "Multipath I/O support"
161 depends on BLK_DEV_MD
162 help
163 MD_MULTIPATH provides a simple multi-path personality for use
164 the MD framework. It is not under active development. New
165 projects should consider using DM_MULTIPATH which has more
166 features and more testing.
167
168 If unsure, say N.
169
170config MD_FAULTY
171 tristate "Faulty test module for MD"
172 depends on BLK_DEV_MD
173 help
174 The "faulty" module allows for a block device that occasionally returns
175 read or write errors. It is useful for testing.
176
177 In unsure, say N.
178
179
180config MD_CLUSTER
181 tristate "Cluster Support for MD (EXPERIMENTAL)"
182 depends on BLK_DEV_MD
183 depends on DLM
184 default n
185 ---help---
186 Clustering support for MD devices. This enables locking and
187 synchronization across multiple systems on the cluster, so all
188 nodes in the cluster can access the MD devices simultaneously.
189
190 This brings the redundancy (and uptime) of RAID levels across the
191 nodes of the cluster.
192
193 If unsure, say N.
194
195source "drivers/md/bcache/Kconfig"
196
197config BLK_DEV_DM_BUILTIN
198 bool
199
200config BLK_DEV_DM
201 tristate "Device mapper support"
202 select BLK_DEV_DM_BUILTIN
203 ---help---
204 Device-mapper is a low level volume manager. It works by allowing
205 people to specify mappings for ranges of logical sectors. Various
206 mapping types are available, in addition people may write their own
207 modules containing custom mappings if they wish.
208
209 Higher level volume managers such as LVM2 use this driver.
210
211 To compile this as a module, choose M here: the module will be
212 called dm-mod.
213
214 If unsure, say N.
215
216config DM_MQ_DEFAULT
217 bool "request-based DM: use blk-mq I/O path by default"
218 depends on BLK_DEV_DM
219 ---help---
220 This option enables the blk-mq based I/O path for request-based
221 DM devices by default. With the option the dm_mod.use_blk_mq
222 module/boot option defaults to Y, without it to N, but it can
223 still be overriden either way.
224
225 If unsure say N.
226
227config DM_DEBUG
228 bool "Device mapper debugging support"
229 depends on BLK_DEV_DM
230 ---help---
231 Enable this for messages that may help debug device-mapper problems.
232
233 If unsure, say N.
234
235config DM_BUFIO
236 tristate
237 depends on BLK_DEV_DM
238 ---help---
239 This interface allows you to do buffered I/O on a device and acts
240 as a cache, holding recently-read blocks in memory and performing
241 delayed writes.
242
243config DM_DEBUG_BLOCK_MANAGER_LOCKING
244 bool "Block manager locking"
245 depends on DM_BUFIO
246 ---help---
247 Block manager locking can catch various metadata corruption issues.
248
249 If unsure, say N.
250
251config DM_DEBUG_BLOCK_STACK_TRACING
252 bool "Keep stack trace of persistent data block lock holders"
253 depends on STACKTRACE_SUPPORT && DM_DEBUG_BLOCK_MANAGER_LOCKING
254 select STACKTRACE
255 ---help---
256 Enable this for messages that may help debug problems with the
257 block manager locking used by thin provisioning and caching.
258
259 If unsure, say N.
260
261config DM_BIO_PRISON
262 tristate
263 depends on BLK_DEV_DM
264 ---help---
265 Some bio locking schemes used by other device-mapper targets
266 including thin provisioning.
267
268source "drivers/md/persistent-data/Kconfig"
269
270config DM_CRYPT
271 tristate "Crypt target support"
272 depends on BLK_DEV_DM
273 select CRYPTO
274 select CRYPTO_CBC
275 ---help---
276 This device-mapper target allows you to create a device that
277 transparently encrypts the data on it. You'll need to activate
278 the ciphers you're going to use in the cryptoapi configuration.
279
280 For further information on dm-crypt and userspace tools see:
281 <https://gitlab.com/cryptsetup/cryptsetup/wikis/DMCrypt>
282
283 To compile this code as a module, choose M here: the module will
284 be called dm-crypt.
285
286 If unsure, say N.
287
288config DM_SNAPSHOT
289 tristate "Snapshot target"
290 depends on BLK_DEV_DM
291 select DM_BUFIO
292 ---help---
293 Allow volume managers to take writable snapshots of a device.
294
295config DM_THIN_PROVISIONING
296 tristate "Thin provisioning target"
297 depends on BLK_DEV_DM
298 select DM_PERSISTENT_DATA
299 select DM_BIO_PRISON
300 ---help---
301 Provides thin provisioning and snapshots that share a data store.
302
303config DM_CACHE
304 tristate "Cache target (EXPERIMENTAL)"
305 depends on BLK_DEV_DM
306 default n
307 select DM_PERSISTENT_DATA
308 select DM_BIO_PRISON
309 ---help---
310 dm-cache attempts to improve performance of a block device by
311 moving frequently used data to a smaller, higher performance
312 device. Different 'policy' plugins can be used to change the
313 algorithms used to select which blocks are promoted, demoted,
314 cleaned etc. It supports writeback and writethrough modes.
315
316config DM_CACHE_SMQ
317 tristate "Stochastic MQ Cache Policy (EXPERIMENTAL)"
318 depends on DM_CACHE
319 default y
320 ---help---
321 A cache policy that uses a multiqueue ordered by recent hits
322 to select which blocks should be promoted and demoted.
323 This is meant to be a general purpose policy. It prioritises
324 reads over writes. This SMQ policy (vs MQ) offers the promise
325 of less memory utilization, improved performance and increased
326 adaptability in the face of changing workloads.
327
328config DM_CACHE_CLEANER
329 tristate "Cleaner Cache Policy (EXPERIMENTAL)"
330 depends on DM_CACHE
331 default y
332 ---help---
333 A simple cache policy that writes back all data to the
334 origin. Used when decommissioning a dm-cache.
335
336config DM_ERA
337 tristate "Era target (EXPERIMENTAL)"
338 depends on BLK_DEV_DM
339 default n
340 select DM_PERSISTENT_DATA
341 select DM_BIO_PRISON
342 ---help---
343 dm-era tracks which parts of a block device are written to
344 over time. Useful for maintaining cache coherency when using
345 vendor snapshots.
346
347config DM_MIRROR
348 tristate "Mirror target"
349 depends on BLK_DEV_DM
350 ---help---
351 Allow volume managers to mirror logical volumes, also
352 needed for live data migration tools such as 'pvmove'.
353
354config DM_LOG_USERSPACE
355 tristate "Mirror userspace logging"
356 depends on DM_MIRROR && NET
357 select CONNECTOR
358 ---help---
359 The userspace logging module provides a mechanism for
360 relaying the dm-dirty-log API to userspace. Log designs
361 which are more suited to userspace implementation (e.g.
362 shared storage logs) or experimental logs can be implemented
363 by leveraging this framework.
364
365config DM_RAID
366 tristate "RAID 1/4/5/6/10 target"
367 depends on BLK_DEV_DM
368 select MD_RAID1
369 select MD_RAID10
370 select MD_RAID456
371 select BLK_DEV_MD
372 ---help---
373 A dm target that supports RAID1, RAID10, RAID4, RAID5 and RAID6 mappings
374
375 A RAID-5 set of N drives with a capacity of C MB per drive provides
376 the capacity of C * (N - 1) MB, and protects against a failure
377 of a single drive. For a given sector (row) number, (N - 1) drives
378 contain data sectors, and one drive contains the parity protection.
379 For a RAID-4 set, the parity blocks are present on a single drive,
380 while a RAID-5 set distributes the parity across the drives in one
381 of the available parity distribution methods.
382
383 A RAID-6 set of N drives with a capacity of C MB per drive
384 provides the capacity of C * (N - 2) MB, and protects
385 against a failure of any two drives. For a given sector
386 (row) number, (N - 2) drives contain data sectors, and two
387 drives contains two independent redundancy syndromes. Like
388 RAID-5, RAID-6 distributes the syndromes across the drives
389 in one of the available parity distribution methods.
390
391config DM_ZERO
392 tristate "Zero target"
393 depends on BLK_DEV_DM
394 ---help---
395 A target that discards writes, and returns all zeroes for
396 reads. Useful in some recovery situations.
397
398config DM_MULTIPATH
399 tristate "Multipath target"
400 depends on BLK_DEV_DM
401 # nasty syntax but means make DM_MULTIPATH independent
402 # of SCSI_DH if the latter isn't defined but if
403 # it is, DM_MULTIPATH must depend on it. We get a build
404 # error if SCSI_DH=m and DM_MULTIPATH=y
405 depends on !SCSI_DH || SCSI
406 ---help---
407 Allow volume managers to support multipath hardware.
408
409config DM_MULTIPATH_QL
410 tristate "I/O Path Selector based on the number of in-flight I/Os"
411 depends on DM_MULTIPATH
412 ---help---
413 This path selector is a dynamic load balancer which selects
414 the path with the least number of in-flight I/Os.
415
416 If unsure, say N.
417
418config DM_MULTIPATH_ST
419 tristate "I/O Path Selector based on the service time"
420 depends on DM_MULTIPATH
421 ---help---
422 This path selector is a dynamic load balancer which selects
423 the path expected to complete the incoming I/O in the shortest
424 time.
425
426 If unsure, say N.
427
428config DM_DELAY
429 tristate "I/O delaying target"
430 depends on BLK_DEV_DM
431 ---help---
432 A target that delays reads and/or writes and can send
433 them to different devices. Useful for testing.
434
435 If unsure, say N.
436
437config DM_UEVENT
438 bool "DM uevents"
439 depends on BLK_DEV_DM
440 ---help---
441 Generate udev events for DM events.
442
443config DM_FLAKEY
444 tristate "Flakey target"
445 depends on BLK_DEV_DM
446 ---help---
447 A target that intermittently fails I/O for debugging purposes.
448
449config DM_VERITY
450 tristate "Verity target support"
451 depends on BLK_DEV_DM
452 select CRYPTO
453 select CRYPTO_HASH
454 select DM_BUFIO
455 ---help---
456 This device-mapper target creates a read-only device that
457 transparently validates the data on one underlying device against
458 a pre-generated tree of cryptographic checksums stored on a second
459 device.
460
461 You'll need to activate the digests you're going to use in the
462 cryptoapi configuration.
463
464 To compile this code as a module, choose M here: the module will
465 be called dm-verity.
466
467 If unsure, say N.
468
469config DM_VERITY_FEC
470 bool "Verity forward error correction support"
471 depends on DM_VERITY
472 select REED_SOLOMON
473 select REED_SOLOMON_DEC8
474 ---help---
475 Add forward error correction support to dm-verity. This option
476 makes it possible to use pre-generated error correction data to
477 recover from corrupted blocks.
478
479 If unsure, say N.
480
481config DM_SWITCH
482 tristate "Switch target support (EXPERIMENTAL)"
483 depends on BLK_DEV_DM
484 ---help---
485 This device-mapper target creates a device that supports an arbitrary
486 mapping of fixed-size regions of I/O across a fixed set of paths.
487 The path used for any specific region can be switched dynamically
488 by sending the target a message.
489
490 To compile this code as a module, choose M here: the module will
491 be called dm-switch.
492
493 If unsure, say N.
494
495config DM_LOG_WRITES
496 tristate "Log writes target support"
497 depends on BLK_DEV_DM
498 ---help---
499 This device-mapper target takes two devices, one device to use
500 normally, one to log all write operations done to the first device.
501 This is for use by file system developers wishing to verify that
502 their fs is writing a consistent file system at all times by allowing
503 them to replay the log in a variety of ways and to check the
504 contents.
505
506 To compile this code as a module, choose M here: the module will
507 be called dm-log-writes.
508
509 If unsure, say N.
510
511endif # MD