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 <http://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 <http://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 <http://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 <http://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 select CRYPTO 273 select CRYPTO_CBC 274 select CRYPTO_ESSIV 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_WRITECACHE 329 tristate "Writecache target" 330 depends on BLK_DEV_DM 331 ---help--- 332 The writecache target caches writes on persistent memory or SSD. 333 It is intended for databases or other programs that need extremely 334 low commit latency. 335 336 The writecache target doesn't cache reads because reads are supposed 337 to be cached in standard RAM. 338 339config DM_ERA 340 tristate "Era target (EXPERIMENTAL)" 341 depends on BLK_DEV_DM 342 default n 343 select DM_PERSISTENT_DATA 344 select DM_BIO_PRISON 345 ---help--- 346 dm-era tracks which parts of a block device are written to 347 over time. Useful for maintaining cache coherency when using 348 vendor snapshots. 349 350config DM_CLONE 351 tristate "Clone target (EXPERIMENTAL)" 352 depends on BLK_DEV_DM 353 default n 354 select DM_PERSISTENT_DATA 355 ---help--- 356 dm-clone produces a one-to-one copy of an existing, read-only source 357 device into a writable destination device. The cloned device is 358 visible/mountable immediately and the copy of the source device to the 359 destination device happens in the background, in parallel with user 360 I/O. 361 362 If unsure, say N. 363 364config DM_MIRROR 365 tristate "Mirror target" 366 depends on BLK_DEV_DM 367 ---help--- 368 Allow volume managers to mirror logical volumes, also 369 needed for live data migration tools such as 'pvmove'. 370 371config DM_LOG_USERSPACE 372 tristate "Mirror userspace logging" 373 depends on DM_MIRROR && NET 374 select CONNECTOR 375 ---help--- 376 The userspace logging module provides a mechanism for 377 relaying the dm-dirty-log API to userspace. Log designs 378 which are more suited to userspace implementation (e.g. 379 shared storage logs) or experimental logs can be implemented 380 by leveraging this framework. 381 382config DM_RAID 383 tristate "RAID 1/4/5/6/10 target" 384 depends on BLK_DEV_DM 385 select MD_RAID0 386 select MD_RAID1 387 select MD_RAID10 388 select MD_RAID456 389 select BLK_DEV_MD 390 ---help--- 391 A dm target that supports RAID1, RAID10, RAID4, RAID5 and RAID6 mappings 392 393 A RAID-5 set of N drives with a capacity of C MB per drive provides 394 the capacity of C * (N - 1) MB, and protects against a failure 395 of a single drive. For a given sector (row) number, (N - 1) drives 396 contain data sectors, and one drive contains the parity protection. 397 For a RAID-4 set, the parity blocks are present on a single drive, 398 while a RAID-5 set distributes the parity across the drives in one 399 of the available parity distribution methods. 400 401 A RAID-6 set of N drives with a capacity of C MB per drive 402 provides the capacity of C * (N - 2) MB, and protects 403 against a failure of any two drives. For a given sector 404 (row) number, (N - 2) drives contain data sectors, and two 405 drives contains two independent redundancy syndromes. Like 406 RAID-5, RAID-6 distributes the syndromes across the drives 407 in one of the available parity distribution methods. 408 409config DM_ZERO 410 tristate "Zero target" 411 depends on BLK_DEV_DM 412 ---help--- 413 A target that discards writes, and returns all zeroes for 414 reads. Useful in some recovery situations. 415 416config DM_MULTIPATH 417 tristate "Multipath target" 418 depends on BLK_DEV_DM 419 # nasty syntax but means make DM_MULTIPATH independent 420 # of SCSI_DH if the latter isn't defined but if 421 # it is, DM_MULTIPATH must depend on it. We get a build 422 # error if SCSI_DH=m and DM_MULTIPATH=y 423 depends on !SCSI_DH || SCSI 424 ---help--- 425 Allow volume managers to support multipath hardware. 426 427config DM_MULTIPATH_QL 428 tristate "I/O Path Selector based on the number of in-flight I/Os" 429 depends on DM_MULTIPATH 430 ---help--- 431 This path selector is a dynamic load balancer which selects 432 the path with the least number of in-flight I/Os. 433 434 If unsure, say N. 435 436config DM_MULTIPATH_ST 437 tristate "I/O Path Selector based on the service time" 438 depends on DM_MULTIPATH 439 ---help--- 440 This path selector is a dynamic load balancer which selects 441 the path expected to complete the incoming I/O in the shortest 442 time. 443 444 If unsure, say N. 445 446config DM_DELAY 447 tristate "I/O delaying target" 448 depends on BLK_DEV_DM 449 ---help--- 450 A target that delays reads and/or writes and can send 451 them to different devices. Useful for testing. 452 453 If unsure, say N. 454 455config DM_DUST 456 tristate "Bad sector simulation target" 457 depends on BLK_DEV_DM 458 ---help--- 459 A target that simulates bad sector behavior. 460 Useful for testing. 461 462 If unsure, say N. 463 464config DM_INIT 465 bool "DM \"dm-mod.create=\" parameter support" 466 depends on BLK_DEV_DM=y 467 ---help--- 468 Enable "dm-mod.create=" parameter to create mapped devices at init time. 469 This option is useful to allow mounting rootfs without requiring an 470 initramfs. 471 See Documentation/admin-guide/device-mapper/dm-init.rst for dm-mod.create="..." 472 format. 473 474 If unsure, say N. 475 476config DM_UEVENT 477 bool "DM uevents" 478 depends on BLK_DEV_DM 479 ---help--- 480 Generate udev events for DM events. 481 482config DM_FLAKEY 483 tristate "Flakey target" 484 depends on BLK_DEV_DM 485 ---help--- 486 A target that intermittently fails I/O for debugging purposes. 487 488config DM_VERITY 489 tristate "Verity target support" 490 depends on BLK_DEV_DM 491 select CRYPTO 492 select CRYPTO_HASH 493 select DM_BUFIO 494 ---help--- 495 This device-mapper target creates a read-only device that 496 transparently validates the data on one underlying device against 497 a pre-generated tree of cryptographic checksums stored on a second 498 device. 499 500 You'll need to activate the digests you're going to use in the 501 cryptoapi configuration. 502 503 To compile this code as a module, choose M here: the module will 504 be called dm-verity. 505 506 If unsure, say N. 507 508config DM_VERITY_VERIFY_ROOTHASH_SIG 509 def_bool n 510 bool "Verity data device root hash signature verification support" 511 depends on DM_VERITY 512 select SYSTEM_DATA_VERIFICATION 513 help 514 Add ability for dm-verity device to be validated if the 515 pre-generated tree of cryptographic checksums passed has a pkcs#7 516 signature file that can validate the roothash of the tree. 517 518 If unsure, say N. 519 520config DM_VERITY_FEC 521 bool "Verity forward error correction support" 522 depends on DM_VERITY 523 select REED_SOLOMON 524 select REED_SOLOMON_DEC8 525 ---help--- 526 Add forward error correction support to dm-verity. This option 527 makes it possible to use pre-generated error correction data to 528 recover from corrupted blocks. 529 530 If unsure, say N. 531 532config DM_SWITCH 533 tristate "Switch target support (EXPERIMENTAL)" 534 depends on BLK_DEV_DM 535 ---help--- 536 This device-mapper target creates a device that supports an arbitrary 537 mapping of fixed-size regions of I/O across a fixed set of paths. 538 The path used for any specific region can be switched dynamically 539 by sending the target a message. 540 541 To compile this code as a module, choose M here: the module will 542 be called dm-switch. 543 544 If unsure, say N. 545 546config DM_LOG_WRITES 547 tristate "Log writes target support" 548 depends on BLK_DEV_DM 549 ---help--- 550 This device-mapper target takes two devices, one device to use 551 normally, one to log all write operations done to the first device. 552 This is for use by file system developers wishing to verify that 553 their fs is writing a consistent file system at all times by allowing 554 them to replay the log in a variety of ways and to check the 555 contents. 556 557 To compile this code as a module, choose M here: the module will 558 be called dm-log-writes. 559 560 If unsure, say N. 561 562config DM_INTEGRITY 563 tristate "Integrity target support" 564 depends on BLK_DEV_DM 565 select BLK_DEV_INTEGRITY 566 select DM_BUFIO 567 select CRYPTO 568 select ASYNC_XOR 569 ---help--- 570 This device-mapper target emulates a block device that has 571 additional per-sector tags that can be used for storing 572 integrity information. 573 574 This integrity target is used with the dm-crypt target to 575 provide authenticated disk encryption or it can be used 576 standalone. 577 578 To compile this code as a module, choose M here: the module will 579 be called dm-integrity. 580 581config DM_ZONED 582 tristate "Drive-managed zoned block device target support" 583 depends on BLK_DEV_DM 584 depends on BLK_DEV_ZONED 585 ---help--- 586 This device-mapper target takes a host-managed or host-aware zoned 587 block device and exposes most of its capacity as a regular block 588 device (drive-managed zoned block device) without any write 589 constraints. This is mainly intended for use with file systems that 590 do not natively support zoned block devices but still want to 591 benefit from the increased capacity offered by SMR disks. Other uses 592 by applications using raw block devices (for example object stores) 593 are also possible. 594 595 To compile this code as a module, choose M here: the module will 596 be called dm-zoned. 597 598 If unsure, say N. 599 600endif # MD 601