drivers/md/Kconfig

   1 #
   2 # Block device driver configuration
   3 #
   4
   5 menuconfig 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
  13 if MD
  14
  15 config 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
  34 config 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
  48 config 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
  61 config 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
  81 config 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
 103 config 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           https://www.kernel.org/pub/linux/utils/raid/mdadm/
 119
 120           If unsure, say Y.
 121
 122 config 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
 159 config 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
 170 config 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
 180 config MD_CLUSTER
 181         tristate "Cluster Support for MD"
 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. Currently, it can work with raid1 and raid10
 192         (limited support).
 193
 194         If unsure, say N.
 195
 196 source "drivers/md/bcache/Kconfig"
 197
 198 config BLK_DEV_DM_BUILTIN
 199         bool
 200
 201 config BLK_DEV_DM
 202         tristate "Device mapper support"
 203         select BLK_DEV_DM_BUILTIN
 204         select DAX
 205         ---help---
 206           Device-mapper is a low level volume manager.  It works by allowing
 207           people to specify mappings for ranges of logical sectors.  Various
 208           mapping types are available, in addition people may write their own
 209           modules containing custom mappings if they wish.
 210
 211           Higher level volume managers such as LVM2 use this driver.
 212
 213           To compile this as a module, choose M here: the module will be
 214           called dm-mod.
 215
 216           If unsure, say N.
 217
 218 config DM_MQ_DEFAULT
 219         bool "request-based DM: use blk-mq I/O path by default"
 220         depends on BLK_DEV_DM
 221         ---help---
 222           This option enables the blk-mq based I/O path for request-based
 223           DM devices by default.  With the option the dm_mod.use_blk_mq
 224           module/boot option defaults to Y, without it to N, but it can
 225           still be overriden either way.
 226
 227           If unsure say N.
 228
 229 config DM_DEBUG
 230         bool "Device mapper debugging support"
 231         depends on BLK_DEV_DM
 232         ---help---
 233           Enable this for messages that may help debug device-mapper problems.
 234
 235           If unsure, say N.
 236
 237 config DM_BUFIO
 238        tristate
 239        depends on BLK_DEV_DM
 240        ---help---
 241          This interface allows you to do buffered I/O on a device and acts
 242          as a cache, holding recently-read blocks in memory and performing
 243          delayed writes.
 244
 245 config DM_DEBUG_BLOCK_MANAGER_LOCKING
 246        bool "Block manager locking"
 247        depends on DM_BUFIO
 248        ---help---
 249          Block manager locking can catch various metadata corruption issues.
 250
 251          If unsure, say N.
 252
 253 config DM_DEBUG_BLOCK_STACK_TRACING
 254        bool "Keep stack trace of persistent data block lock holders"
 255        depends on STACKTRACE_SUPPORT && DM_DEBUG_BLOCK_MANAGER_LOCKING
 256        select STACKTRACE
 257        ---help---
 258          Enable this for messages that may help debug problems with the
 259          block manager locking used by thin provisioning and caching.
 260
 261          If unsure, say N.
 262
 263 config DM_BIO_PRISON
 264        tristate
 265        depends on BLK_DEV_DM
 266        ---help---
 267          Some bio locking schemes used by other device-mapper targets
 268          including thin provisioning.
 269
 270 source "drivers/md/persistent-data/Kconfig"
 271
 272 config DM_CRYPT
 273         tristate "Crypt target support"
 274         depends on BLK_DEV_DM
 275         select CRYPTO
 276         select CRYPTO_CBC
 277         ---help---
 278           This device-mapper target allows you to create a device that
 279           transparently encrypts the data on it. You'll need to activate
 280           the ciphers you're going to use in the cryptoapi configuration.
 281
 282           For further information on dm-crypt and userspace tools see:
 283           <https://gitlab.com/cryptsetup/cryptsetup/wikis/DMCrypt>
 284
 285           To compile this code as a module, choose M here: the module will
 286           be called dm-crypt.
 287
 288           If unsure, say N.
 289
 290 config DM_SNAPSHOT
 291        tristate "Snapshot target"
 292        depends on BLK_DEV_DM
 293        select DM_BUFIO
 294        ---help---
 295          Allow volume managers to take writable snapshots of a device.
 296
 297 config DM_THIN_PROVISIONING
 298        tristate "Thin provisioning target"
 299        depends on BLK_DEV_DM
 300        select DM_PERSISTENT_DATA
 301        select DM_BIO_PRISON
 302        ---help---
 303          Provides thin provisioning and snapshots that share a data store.
 304
 305 config DM_CACHE
 306        tristate "Cache target (EXPERIMENTAL)"
 307        depends on BLK_DEV_DM
 308        default n
 309        select DM_PERSISTENT_DATA
 310        select DM_BIO_PRISON
 311        ---help---
 312          dm-cache attempts to improve performance of a block device by
 313          moving frequently used data to a smaller, higher performance
 314          device.  Different 'policy' plugins can be used to change the
 315          algorithms used to select which blocks are promoted, demoted,
 316          cleaned etc.  It supports writeback and writethrough modes.
 317
 318 config DM_CACHE_SMQ
 319        tristate "Stochastic MQ Cache Policy (EXPERIMENTAL)"
 320        depends on DM_CACHE
 321        default y
 322        ---help---
 323          A cache policy that uses a multiqueue ordered by recent hits
 324          to select which blocks should be promoted and demoted.
 325          This is meant to be a general purpose policy.  It prioritises
 326          reads over writes.  This SMQ policy (vs MQ) offers the promise
 327          of less memory utilization, improved performance and increased
 328          adaptability in the face of changing workloads.
 329
 330 config DM_ERA
 331        tristate "Era target (EXPERIMENTAL)"
 332        depends on BLK_DEV_DM
 333        default n
 334        select DM_PERSISTENT_DATA
 335        select DM_BIO_PRISON
 336        ---help---
 337          dm-era tracks which parts of a block device are written to
 338          over time.  Useful for maintaining cache coherency when using
 339          vendor snapshots.
 340
 341 config DM_MIRROR
 342        tristate "Mirror target"
 343        depends on BLK_DEV_DM
 344        ---help---
 345          Allow volume managers to mirror logical volumes, also
 346          needed for live data migration tools such as 'pvmove'.
 347
 348 config DM_LOG_USERSPACE
 349         tristate "Mirror userspace logging"
 350         depends on DM_MIRROR && NET
 351         select CONNECTOR
 352         ---help---
 353           The userspace logging module provides a mechanism for
 354           relaying the dm-dirty-log API to userspace.  Log designs
 355           which are more suited to userspace implementation (e.g.
 356           shared storage logs) or experimental logs can be implemented
 357           by leveraging this framework.
 358
 359 config DM_RAID
 360        tristate "RAID 1/4/5/6/10 target"
 361        depends on BLK_DEV_DM
 362        select MD_RAID0
 363        select MD_RAID1
 364        select MD_RAID10
 365        select MD_RAID456
 366        select BLK_DEV_MD
 367        ---help---
 368          A dm target that supports RAID1, RAID10, RAID4, RAID5 and RAID6 mappings
 369
 370          A RAID-5 set of N drives with a capacity of C MB per drive provides
 371          the capacity of C * (N - 1) MB, and protects against a failure
 372          of a single drive. For a given sector (row) number, (N - 1) drives
 373          contain data sectors, and one drive contains the parity protection.
 374          For a RAID-4 set, the parity blocks are present on a single drive,
 375          while a RAID-5 set distributes the parity across the drives in one
 376          of the available parity distribution methods.
 377
 378          A RAID-6 set of N drives with a capacity of C MB per drive
 379          provides the capacity of C * (N - 2) MB, and protects
 380          against a failure of any two drives. For a given sector
 381          (row) number, (N - 2) drives contain data sectors, and two
 382          drives contains two independent redundancy syndromes.  Like
 383          RAID-5, RAID-6 distributes the syndromes across the drives
 384          in one of the available parity distribution methods.
 385
 386 config DM_ZERO
 387         tristate "Zero target"
 388         depends on BLK_DEV_DM
 389         ---help---
 390           A target that discards writes, and returns all zeroes for
 391           reads.  Useful in some recovery situations.
 392
 393 config DM_MULTIPATH
 394         tristate "Multipath target"
 395         depends on BLK_DEV_DM
 396         # nasty syntax but means make DM_MULTIPATH independent
 397         # of SCSI_DH if the latter isn't defined but if
 398         # it is, DM_MULTIPATH must depend on it.  We get a build
 399         # error if SCSI_DH=m and DM_MULTIPATH=y
 400         depends on !SCSI_DH || SCSI
 401         ---help---
 402           Allow volume managers to support multipath hardware.
 403
 404 config DM_MULTIPATH_QL
 405         tristate "I/O Path Selector based on the number of in-flight I/Os"
 406         depends on DM_MULTIPATH
 407         ---help---
 408           This path selector is a dynamic load balancer which selects
 409           the path with the least number of in-flight I/Os.
 410
 411           If unsure, say N.
 412
 413 config DM_MULTIPATH_ST
 414         tristate "I/O Path Selector based on the service time"
 415         depends on DM_MULTIPATH
 416         ---help---
 417           This path selector is a dynamic load balancer which selects
 418           the path expected to complete the incoming I/O in the shortest
 419           time.
 420
 421           If unsure, say N.
 422
 423 config DM_DELAY
 424         tristate "I/O delaying target"
 425         depends on BLK_DEV_DM
 426         ---help---
 427         A target that delays reads and/or writes and can send
 428         them to different devices.  Useful for testing.
 429
 430         If unsure, say N.
 431
 432 config DM_UEVENT
 433         bool "DM uevents"
 434         depends on BLK_DEV_DM
 435         ---help---
 436         Generate udev events for DM events.
 437
 438 config DM_FLAKEY
 439        tristate "Flakey target"
 440        depends on BLK_DEV_DM
 441        ---help---
 442          A target that intermittently fails I/O for debugging purposes.
 443
 444 config DM_VERITY
 445         tristate "Verity target support"
 446         depends on BLK_DEV_DM
 447         select CRYPTO
 448         select CRYPTO_HASH
 449         select DM_BUFIO
 450         ---help---
 451           This device-mapper target creates a read-only device that
 452           transparently validates the data on one underlying device against
 453           a pre-generated tree of cryptographic checksums stored on a second
 454           device.
 455
 456           You'll need to activate the digests you're going to use in the
 457           cryptoapi configuration.
 458
 459           To compile this code as a module, choose M here: the module will
 460           be called dm-verity.
 461
 462           If unsure, say N.
 463
 464 config DM_VERITY_FEC
 465         bool "Verity forward error correction support"
 466         depends on DM_VERITY
 467         select REED_SOLOMON
 468         select REED_SOLOMON_DEC8
 469         ---help---
 470           Add forward error correction support to dm-verity. This option
 471           makes it possible to use pre-generated error correction data to
 472           recover from corrupted blocks.
 473
 474           If unsure, say N.
 475
 476 config DM_SWITCH
 477         tristate "Switch target support (EXPERIMENTAL)"
 478         depends on BLK_DEV_DM
 479         ---help---
 480           This device-mapper target creates a device that supports an arbitrary
 481           mapping of fixed-size regions of I/O across a fixed set of paths.
 482           The path used for any specific region can be switched dynamically
 483           by sending the target a message.
 484
 485           To compile this code as a module, choose M here: the module will
 486           be called dm-switch.
 487
 488           If unsure, say N.
 489
 490 config DM_LOG_WRITES
 491         tristate "Log writes target support"
 492         depends on BLK_DEV_DM
 493         ---help---
 494           This device-mapper target takes two devices, one device to use
 495           normally, one to log all write operations done to the first device.
 496           This is for use by file system developers wishing to verify that
 497           their fs is writing a consistent file system at all times by allowing
 498           them to replay the log in a variety of ways and to check the
 499           contents.
 500
 501           To compile this code as a module, choose M here: the module will
 502           be called dm-log-writes.
 503
 504           If unsure, say N.
 505
 506 config DM_INTEGRITY
 507         tristate "Integrity target support"
 508         depends on BLK_DEV_DM
 509         select BLK_DEV_INTEGRITY
 510         select DM_BUFIO
 511         select CRYPTO
 512         select ASYNC_XOR
 513         ---help---
 514           This device-mapper target emulates a block device that has
 515           additional per-sector tags that can be used for storing
 516           integrity information.
 517
 518           This integrity target is used with the dm-crypt target to
 519           provide authenticated disk encryption or it can be used
 520           standalone.
 521
 522           To compile this code as a module, choose M here: the module will
 523           be called dm-integrity.
 524
 525 config DM_ZONED
 526         tristate "Drive-managed zoned block device target support"
 527         depends on BLK_DEV_DM
 528         depends on BLK_DEV_ZONED
 529         ---help---
 530           This device-mapper target takes a host-managed or host-aware zoned
 531           block device and exposes most of its capacity as a regular block
 532           device (drive-managed zoned block device) without any write
 533           constraints. This is mainly intended for use with file systems that
 534           do not natively support zoned block devices but still want to
 535           benefit from the increased capacity offered by SMR disks. Other uses
 536           by applications using raw block devices (for example object stores)
 537           are also possible.
 538
 539           To compile this code as a module, choose M here: the module will
 540           be called dm-zoned.
 541
 542           If unsure, say N.
 543
 544 endif # MD