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Linus Torvalds1da177e2005-04-16 15:20:36 -07001#
2# Block device driver configuration
3#
4
Jan Engelhardtafd44032007-07-17 04:06:11 -07005menuconfig MD
Linus Torvalds1da177e2005-04-16 15:20:36 -07006 bool "Multiple devices driver support (RAID and LVM)"
Jan Engelhardtafd44032007-07-17 04:06:11 -07007 depends on BLOCK
Linus Torvalds1da177e2005-04-16 15:20:36 -07008 help
9 Support multiple physical spindles through a single logical device.
10 Required for RAID and logical volume management.
11
Jan Engelhardtafd44032007-07-17 04:06:11 -070012if MD
13
Linus Torvalds1da177e2005-04-16 15:20:36 -070014config BLK_DEV_MD
15 tristate "RAID support"
Linus Torvalds1da177e2005-04-16 15:20:36 -070016 ---help---
17 This driver lets you combine several hard disk partitions into one
18 logical block device. This can be used to simply append one
19 partition to another one or to combine several redundant hard disks
20 into a RAID1/4/5 device so as to provide protection against hard
21 disk failures. This is called "Software RAID" since the combining of
22 the partitions is done by the kernel. "Hardware RAID" means that the
23 combining is done by a dedicated controller; if you have such a
24 controller, you do not need to say Y here.
25
26 More information about Software RAID on Linux is contained in the
27 Software RAID mini-HOWTO, available from
28 <http://www.tldp.org/docs.html#howto>. There you will also learn
29 where to get the supporting user space utilities raidtools.
30
31 If unsure, say N.
32
Arjan van de Vena3640922008-09-21 15:44:32 -070033config MD_AUTODETECT
34 bool "Autodetect RAID arrays during kernel boot"
Alan Jenkinsce52aeb2008-10-10 16:02:53 +010035 depends on BLK_DEV_MD=y
Arjan van de Vena3640922008-09-21 15:44:32 -070036 default y
37 ---help---
38 If you say Y here, then the kernel will try to autodetect raid
39 arrays as part of its boot process.
40
41 If you don't use raid and say Y, this autodetection can cause
42 a several-second delay in the boot time due to various
43 synchronisation steps that are part of this step.
44
45 If unsure, say Y.
46
Linus Torvalds1da177e2005-04-16 15:20:36 -070047config MD_LINEAR
48 tristate "Linear (append) mode"
49 depends on BLK_DEV_MD
50 ---help---
51 If you say Y here, then your multiple devices driver will be able to
52 use the so-called linear mode, i.e. it will combine the hard disk
53 partitions by simply appending one to the other.
54
55 To compile this as a module, choose M here: the module
56 will be called linear.
57
58 If unsure, say Y.
59
60config MD_RAID0
61 tristate "RAID-0 (striping) mode"
62 depends on BLK_DEV_MD
63 ---help---
64 If you say Y here, then your multiple devices driver will be able to
65 use the so-called raid0 mode, i.e. it will combine the hard disk
66 partitions into one logical device in such a fashion as to fill them
67 up evenly, one chunk here and one chunk there. This will increase
68 the throughput rate if the partitions reside on distinct disks.
69
70 Information about Software RAID on Linux is contained in the
71 Software-RAID mini-HOWTO, available from
72 <http://www.tldp.org/docs.html#howto>. There you will also
73 learn where to get the supporting user space utilities raidtools.
74
75 To compile this as a module, choose M here: the module
76 will be called raid0.
77
78 If unsure, say Y.
79
80config MD_RAID1
81 tristate "RAID-1 (mirroring) mode"
82 depends on BLK_DEV_MD
83 ---help---
84 A RAID-1 set consists of several disk drives which are exact copies
85 of each other. In the event of a mirror failure, the RAID driver
86 will continue to use the operational mirrors in the set, providing
87 an error free MD (multiple device) to the higher levels of the
88 kernel. In a set with N drives, the available space is the capacity
89 of a single drive, and the set protects against a failure of (N - 1)
90 drives.
91
92 Information about Software RAID on Linux is contained in the
93 Software-RAID mini-HOWTO, available from
94 <http://www.tldp.org/docs.html#howto>. There you will also
95 learn where to get the supporting user space utilities raidtools.
96
97 If you want to use such a RAID-1 set, say Y. To compile this code
98 as a module, choose M here: the module will be called raid1.
99
100 If unsure, say Y.
101
102config MD_RAID10
103 tristate "RAID-10 (mirrored striping) mode (EXPERIMENTAL)"
104 depends on BLK_DEV_MD && EXPERIMENTAL
105 ---help---
106 RAID-10 provides a combination of striping (RAID-0) and
Justin Piszcz4d2554d2006-06-26 00:27:50 -0700107 mirroring (RAID-1) with easier configuration and more flexible
Linus Torvalds1da177e2005-04-16 15:20:36 -0700108 layout.
109 Unlike RAID-0, but like RAID-1, RAID-10 requires all devices to
110 be the same size (or at least, only as much as the smallest device
111 will be used).
112 RAID-10 provides a variety of layouts that provide different levels
113 of redundancy and performance.
114
115 RAID-10 requires mdadm-1.7.0 or later, available at:
116
117 ftp://ftp.kernel.org/pub/linux/utils/raid/mdadm/
118
119 If unsure, say Y.
120
NeilBrown16a53ec2006-06-26 00:27:38 -0700121config MD_RAID456
122 tristate "RAID-4/RAID-5/RAID-6 mode"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700123 depends on BLK_DEV_MD
Dan Williamsf701d582009-03-31 15:09:39 +1100124 select MD_RAID6_PQ
Dan Williams9bc89cd2007-01-02 11:10:44 -0700125 select ASYNC_MEMCPY
126 select ASYNC_XOR
Dan Williamsac6b53b2009-07-14 13:40:19 -0700127 select ASYNC_PQ
128 select ASYNC_RAID6_RECOV
Linus Torvalds1da177e2005-04-16 15:20:36 -0700129 ---help---
130 A RAID-5 set of N drives with a capacity of C MB per drive provides
131 the capacity of C * (N - 1) MB, and protects against a failure
132 of a single drive. For a given sector (row) number, (N - 1) drives
133 contain data sectors, and one drive contains the parity protection.
134 For a RAID-4 set, the parity blocks are present on a single drive,
135 while a RAID-5 set distributes the parity across the drives in one
136 of the available parity distribution methods.
137
NeilBrown16a53ec2006-06-26 00:27:38 -0700138 A RAID-6 set of N drives with a capacity of C MB per drive
139 provides the capacity of C * (N - 2) MB, and protects
140 against a failure of any two drives. For a given sector
141 (row) number, (N - 2) drives contain data sectors, and two
142 drives contains two independent redundancy syndromes. Like
143 RAID-5, RAID-6 distributes the syndromes across the drives
144 in one of the available parity distribution methods.
145
Linus Torvalds1da177e2005-04-16 15:20:36 -0700146 Information about Software RAID on Linux is contained in the
147 Software-RAID mini-HOWTO, available from
148 <http://www.tldp.org/docs.html#howto>. There you will also
149 learn where to get the supporting user space utilities raidtools.
150
NeilBrown16a53ec2006-06-26 00:27:38 -0700151 If you want to use such a RAID-4/RAID-5/RAID-6 set, say Y. To
Linus Torvalds1da177e2005-04-16 15:20:36 -0700152 compile this code as a module, choose M here: the module
NeilBrown16a53ec2006-06-26 00:27:38 -0700153 will be called raid456.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700154
155 If unsure, say Y.
156
Dan Williamsf701d582009-03-31 15:09:39 +1100157config MD_RAID6_PQ
158 tristate
159
Dan Williamscb3c8292009-07-14 12:20:37 -0700160config ASYNC_RAID6_TEST
161 tristate "Self test for hardware accelerated raid6 recovery"
162 depends on MD_RAID6_PQ
163 select ASYNC_RAID6_RECOV
164 ---help---
165 This is a one-shot self test that permutes through the
166 recovery of all the possible two disk failure scenarios for a
167 N-disk array. Recovery is performed with the asynchronous
168 raid6 recovery routines, and will optionally use an offload
169 engine if one is available.
170
171 If unsure, say N.
172
Linus Torvalds1da177e2005-04-16 15:20:36 -0700173config MD_MULTIPATH
174 tristate "Multipath I/O support"
175 depends on BLK_DEV_MD
176 help
177 Multipath-IO is the ability of certain devices to address the same
178 physical disk over multiple 'IO paths'. The code ensures that such
179 paths can be defined and handled at runtime, and ensures that a
180 transparent failover to the backup path(s) happens if a IO errors
181 arrives on the primary path.
182
183 If unsure, say N.
184
185config MD_FAULTY
186 tristate "Faulty test module for MD"
187 depends on BLK_DEV_MD
188 help
189 The "faulty" module allows for a block device that occasionally returns
190 read or write errors. It is useful for testing.
191
192 In unsure, say N.
193
194config BLK_DEV_DM
195 tristate "Device mapper support"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700196 ---help---
197 Device-mapper is a low level volume manager. It works by allowing
198 people to specify mappings for ranges of logical sectors. Various
199 mapping types are available, in addition people may write their own
200 modules containing custom mappings if they wish.
201
202 Higher level volume managers such as LVM2 use this driver.
203
204 To compile this as a module, choose M here: the module will be
205 called dm-mod.
206
207 If unsure, say N.
208
Bryn Reevescc109202006-10-03 01:15:35 -0700209config DM_DEBUG
210 boolean "Device mapper debugging support"
Alasdair G Kergon0149e572008-02-08 02:10:32 +0000211 depends on BLK_DEV_DM
Bryn Reevescc109202006-10-03 01:15:35 -0700212 ---help---
213 Enable this for messages that may help debug device-mapper problems.
214
215 If unsure, say N.
216
Linus Torvalds1da177e2005-04-16 15:20:36 -0700217config DM_CRYPT
218 tristate "Crypt target support"
Alasdair G Kergon0149e572008-02-08 02:10:32 +0000219 depends on BLK_DEV_DM
Linus Torvalds1da177e2005-04-16 15:20:36 -0700220 select CRYPTO
Herbert Xu32632632006-12-10 09:50:36 +1100221 select CRYPTO_CBC
Linus Torvalds1da177e2005-04-16 15:20:36 -0700222 ---help---
223 This device-mapper target allows you to create a device that
224 transparently encrypts the data on it. You'll need to activate
225 the ciphers you're going to use in the cryptoapi configuration.
226
227 Information on how to use dm-crypt can be found on
228
229 <http://www.saout.de/misc/dm-crypt/>
230
231 To compile this code as a module, choose M here: the module will
232 be called dm-crypt.
233
234 If unsure, say N.
235
236config DM_SNAPSHOT
Alasdair G Kergon0149e572008-02-08 02:10:32 +0000237 tristate "Snapshot target"
238 depends on BLK_DEV_DM
Linus Torvalds1da177e2005-04-16 15:20:36 -0700239 ---help---
Justin Piszcz4d2554d2006-06-26 00:27:50 -0700240 Allow volume managers to take writable snapshots of a device.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700241
242config DM_MIRROR
Alasdair G Kergon0149e572008-02-08 02:10:32 +0000243 tristate "Mirror target"
244 depends on BLK_DEV_DM
Linus Torvalds1da177e2005-04-16 15:20:36 -0700245 ---help---
246 Allow volume managers to mirror logical volumes, also
247 needed for live data migration tools such as 'pvmove'.
248
249config DM_ZERO
Alasdair G Kergon0149e572008-02-08 02:10:32 +0000250 tristate "Zero target"
251 depends on BLK_DEV_DM
Linus Torvalds1da177e2005-04-16 15:20:36 -0700252 ---help---
253 A target that discards writes, and returns all zeroes for
254 reads. Useful in some recovery situations.
255
256config DM_MULTIPATH
Alasdair G Kergon0149e572008-02-08 02:10:32 +0000257 tristate "Multipath target"
258 depends on BLK_DEV_DM
Chandra Seetharamanfe9233f2008-05-23 18:16:40 -0700259 # nasty syntax but means make DM_MULTIPATH independent
260 # of SCSI_DH if the latter isn't defined but if
261 # it is, DM_MULTIPATH must depend on it. We get a build
262 # error if SCSI_DH=m and DM_MULTIPATH=y
263 depends on SCSI_DH || !SCSI_DH
Linus Torvalds1da177e2005-04-16 15:20:36 -0700264 ---help---
265 Allow volume managers to support multipath hardware.
266
Heinz Mauelshagen26b9f222007-05-09 02:33:06 -0700267config DM_DELAY
268 tristate "I/O delaying target (EXPERIMENTAL)"
269 depends on BLK_DEV_DM && EXPERIMENTAL
270 ---help---
271 A target that delays reads and/or writes and can send
272 them to different devices. Useful for testing.
273
274 If unsure, say N.
275
Mike Anderson51e5b2b2007-10-19 22:48:00 +0100276config DM_UEVENT
277 bool "DM uevents (EXPERIMENTAL)"
278 depends on BLK_DEV_DM && EXPERIMENTAL
279 ---help---
280 Generate udev events for DM events.
281
Jan Engelhardtafd44032007-07-17 04:06:11 -0700282endif # MD