PageRenderTime 23ms CodeModel.GetById 1ms app.highlight 9ms RepoModel.GetById 2ms app.codeStats 0ms

/drivers/md/Kconfig

http://github.com/mirrors/linux
#! | 503 lines | 414 code | 89 blank | 0 comment | 0 complexity | 0381b9fe622a3d2c4fc8a750edd8c770 MD5 | raw file
  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_STACK_TRACING
244       bool "Keep stack trace of persistent data block lock holders"
245       depends on STACKTRACE_SUPPORT && DM_BUFIO
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_CRYPT
263	tristate "Crypt target support"
264	depends on BLK_DEV_DM
265	select CRYPTO
266	select CRYPTO_CBC
267	---help---
268	  This device-mapper target allows you to create a device that
269	  transparently encrypts the data on it. You'll need to activate
270	  the ciphers you're going to use in the cryptoapi configuration.
271
272	  For further information on dm-crypt and userspace tools see:
273	  <https://gitlab.com/cryptsetup/cryptsetup/wikis/DMCrypt>
274
275	  To compile this code as a module, choose M here: the module will
276	  be called dm-crypt.
277
278	  If unsure, say N.
279
280config DM_SNAPSHOT
281       tristate "Snapshot target"
282       depends on BLK_DEV_DM
283       select DM_BUFIO
284       ---help---
285         Allow volume managers to take writable snapshots of a device.
286
287config DM_THIN_PROVISIONING
288       tristate "Thin provisioning target"
289       depends on BLK_DEV_DM
290       select DM_PERSISTENT_DATA
291       select DM_BIO_PRISON
292       ---help---
293         Provides thin provisioning and snapshots that share a data store.
294
295config DM_CACHE
296       tristate "Cache target (EXPERIMENTAL)"
297       depends on BLK_DEV_DM
298       default n
299       select DM_PERSISTENT_DATA
300       select DM_BIO_PRISON
301       ---help---
302         dm-cache attempts to improve performance of a block device by
303         moving frequently used data to a smaller, higher performance
304         device.  Different 'policy' plugins can be used to change the
305         algorithms used to select which blocks are promoted, demoted,
306         cleaned etc.  It supports writeback and writethrough modes.
307
308config DM_CACHE_SMQ
309       tristate "Stochastic MQ Cache Policy (EXPERIMENTAL)"
310       depends on DM_CACHE
311       default y
312       ---help---
313         A cache policy that uses a multiqueue ordered by recent hits
314         to select which blocks should be promoted and demoted.
315         This is meant to be a general purpose policy.  It prioritises
316         reads over writes.  This SMQ policy (vs MQ) offers the promise
317         of less memory utilization, improved performance and increased
318         adaptability in the face of changing workloads.
319
320config DM_CACHE_CLEANER
321       tristate "Cleaner Cache Policy (EXPERIMENTAL)"
322       depends on DM_CACHE
323       default y
324       ---help---
325         A simple cache policy that writes back all data to the
326         origin.  Used when decommissioning a dm-cache.
327
328config DM_ERA
329       tristate "Era target (EXPERIMENTAL)"
330       depends on BLK_DEV_DM
331       default n
332       select DM_PERSISTENT_DATA
333       select DM_BIO_PRISON
334       ---help---
335         dm-era tracks which parts of a block device are written to
336         over time.  Useful for maintaining cache coherency when using
337         vendor snapshots.
338
339config DM_MIRROR
340       tristate "Mirror target"
341       depends on BLK_DEV_DM
342       ---help---
343         Allow volume managers to mirror logical volumes, also
344         needed for live data migration tools such as 'pvmove'.
345
346config DM_LOG_USERSPACE
347	tristate "Mirror userspace logging"
348	depends on DM_MIRROR && NET
349	select CONNECTOR
350	---help---
351	  The userspace logging module provides a mechanism for
352	  relaying the dm-dirty-log API to userspace.  Log designs
353	  which are more suited to userspace implementation (e.g.
354	  shared storage logs) or experimental logs can be implemented
355	  by leveraging this framework.
356
357config DM_RAID
358       tristate "RAID 1/4/5/6/10 target"
359       depends on BLK_DEV_DM
360       select MD_RAID1
361       select MD_RAID10
362       select MD_RAID456
363       select BLK_DEV_MD
364       ---help---
365	 A dm target that supports RAID1, RAID10, RAID4, RAID5 and RAID6 mappings
366
367	 A RAID-5 set of N drives with a capacity of C MB per drive provides
368	 the capacity of C * (N - 1) MB, and protects against a failure
369	 of a single drive. For a given sector (row) number, (N - 1) drives
370	 contain data sectors, and one drive contains the parity protection.
371	 For a RAID-4 set, the parity blocks are present on a single drive,
372	 while a RAID-5 set distributes the parity across the drives in one
373	 of the available parity distribution methods.
374
375	 A RAID-6 set of N drives with a capacity of C MB per drive
376	 provides the capacity of C * (N - 2) MB, and protects
377	 against a failure of any two drives. For a given sector
378	 (row) number, (N - 2) drives contain data sectors, and two
379	 drives contains two independent redundancy syndromes.  Like
380	 RAID-5, RAID-6 distributes the syndromes across the drives
381	 in one of the available parity distribution methods.
382
383config DM_ZERO
384	tristate "Zero target"
385	depends on BLK_DEV_DM
386	---help---
387	  A target that discards writes, and returns all zeroes for
388	  reads.  Useful in some recovery situations.
389
390config DM_MULTIPATH
391	tristate "Multipath target"
392	depends on BLK_DEV_DM
393	# nasty syntax but means make DM_MULTIPATH independent
394	# of SCSI_DH if the latter isn't defined but if
395	# it is, DM_MULTIPATH must depend on it.  We get a build
396	# error if SCSI_DH=m and DM_MULTIPATH=y
397	depends on !SCSI_DH || SCSI
398	---help---
399	  Allow volume managers to support multipath hardware.
400
401config DM_MULTIPATH_QL
402	tristate "I/O Path Selector based on the number of in-flight I/Os"
403	depends on DM_MULTIPATH
404	---help---
405	  This path selector is a dynamic load balancer which selects
406	  the path with the least number of in-flight I/Os.
407
408	  If unsure, say N.
409
410config DM_MULTIPATH_ST
411	tristate "I/O Path Selector based on the service time"
412	depends on DM_MULTIPATH
413	---help---
414	  This path selector is a dynamic load balancer which selects
415	  the path expected to complete the incoming I/O in the shortest
416	  time.
417
418	  If unsure, say N.
419
420config DM_DELAY
421	tristate "I/O delaying target"
422	depends on BLK_DEV_DM
423	---help---
424	A target that delays reads and/or writes and can send
425	them to different devices.  Useful for testing.
426
427	If unsure, say N.
428
429config DM_UEVENT
430	bool "DM uevents"
431	depends on BLK_DEV_DM
432	---help---
433	Generate udev events for DM events.
434
435config DM_FLAKEY
436       tristate "Flakey target"
437       depends on BLK_DEV_DM
438       ---help---
439         A target that intermittently fails I/O for debugging purposes.
440
441config DM_VERITY
442	tristate "Verity target support"
443	depends on BLK_DEV_DM
444	select CRYPTO
445	select CRYPTO_HASH
446	select DM_BUFIO
447	---help---
448	  This device-mapper target creates a read-only device that
449	  transparently validates the data on one underlying device against
450	  a pre-generated tree of cryptographic checksums stored on a second
451	  device.
452
453	  You'll need to activate the digests you're going to use in the
454	  cryptoapi configuration.
455
456	  To compile this code as a module, choose M here: the module will
457	  be called dm-verity.
458
459	  If unsure, say N.
460
461config DM_VERITY_FEC
462	bool "Verity forward error correction support"
463	depends on DM_VERITY
464	select REED_SOLOMON
465	select REED_SOLOMON_DEC8
466	---help---
467	  Add forward error correction support to dm-verity. This option
468	  makes it possible to use pre-generated error correction data to
469	  recover from corrupted blocks.
470
471	  If unsure, say N.
472
473config DM_SWITCH
474	tristate "Switch target support (EXPERIMENTAL)"
475	depends on BLK_DEV_DM
476	---help---
477	  This device-mapper target creates a device that supports an arbitrary
478	  mapping of fixed-size regions of I/O across a fixed set of paths.
479	  The path used for any specific region can be switched dynamically
480	  by sending the target a message.
481
482	  To compile this code as a module, choose M here: the module will
483	  be called dm-switch.
484
485	  If unsure, say N.
486
487config DM_LOG_WRITES
488	tristate "Log writes target support"
489	depends on BLK_DEV_DM
490	---help---
491	  This device-mapper target takes two devices, one device to use
492	  normally, one to log all write operations done to the first device.
493	  This is for use by file system developers wishing to verify that
494	  their fs is writing a consistent file system at all times by allowing
495	  them to replay the log in a variety of ways and to check the
496	  contents.
497
498	  To compile this code as a module, choose M here: the module will
499	  be called dm-log-writes.
500
501	  If unsure, say N.
502
503endif # MD