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	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	# nasty syntax but means make DM_MULTIPATH independent
432	# of SCSI_DH if the latter isn't defined but if
433	# it is, DM_MULTIPATH must depend on it.  We get a build
434	# error if SCSI_DH=m and DM_MULTIPATH=y
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	select DM_AUDIT if AUDIT
614	help
615	  This device-mapper target emulates a block device that has
616	  additional per-sector tags that can be used for storing
617	  integrity information.
618
619	  This integrity target is used with the dm-crypt target to
620	  provide authenticated disk encryption or it can be used
621	  standalone.
622
623	  To compile this code as a module, choose M here: the module will
624	  be called dm-integrity.
625
626config DM_ZONED
627	tristate "Drive-managed zoned block device target support"
628	depends on BLK_DEV_DM
629	depends on BLK_DEV_ZONED
630	select CRC32
631	help
632	  This device-mapper target takes a host-managed or host-aware zoned
633	  block device and exposes most of its capacity as a regular block
634	  device (drive-managed zoned block device) without any write
635	  constraints. This is mainly intended for use with file systems that
636	  do not natively support zoned block devices but still want to
637	  benefit from the increased capacity offered by SMR disks. Other uses
638	  by applications using raw block devices (for example object stores)
639	  are also possible.
640
641	  To compile this code as a module, choose M here: the module will
642	  be called dm-zoned.
643
644	  If unsure, say N.
645
646config DM_AUDIT
647	bool "DM audit events"
648	depends on AUDIT
649	help
650	  Generate audit events for device-mapper.
651
652	  Enables audit logging of several security relevant events in the
653	  particular device-mapper targets, especially the integrity target.
654
655endif # MD
656