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 ---help--- 275 This device-mapper target allows you to create a device that 276 transparently encrypts the data on it. You'll need to activate 277 the ciphers you're going to use in the cryptoapi configuration. 278 279 For further information on dm-crypt and userspace tools see: 280 <https://gitlab.com/cryptsetup/cryptsetup/wikis/DMCrypt> 281 282 To compile this code as a module, choose M here: the module will 283 be called dm-crypt. 284 285 If unsure, say N. 286 287config DM_SNAPSHOT 288 tristate "Snapshot target" 289 depends on BLK_DEV_DM 290 select DM_BUFIO 291 ---help--- 292 Allow volume managers to take writable snapshots of a device. 293 294config DM_THIN_PROVISIONING 295 tristate "Thin provisioning target" 296 depends on BLK_DEV_DM 297 select DM_PERSISTENT_DATA 298 select DM_BIO_PRISON 299 ---help--- 300 Provides thin provisioning and snapshots that share a data store. 301 302config DM_CACHE 303 tristate "Cache target (EXPERIMENTAL)" 304 depends on BLK_DEV_DM 305 default n 306 select DM_PERSISTENT_DATA 307 select DM_BIO_PRISON 308 ---help--- 309 dm-cache attempts to improve performance of a block device by 310 moving frequently used data to a smaller, higher performance 311 device. Different 'policy' plugins can be used to change the 312 algorithms used to select which blocks are promoted, demoted, 313 cleaned etc. It supports writeback and writethrough modes. 314 315config DM_CACHE_SMQ 316 tristate "Stochastic MQ Cache Policy (EXPERIMENTAL)" 317 depends on DM_CACHE 318 default y 319 ---help--- 320 A cache policy that uses a multiqueue ordered by recent hits 321 to select which blocks should be promoted and demoted. 322 This is meant to be a general purpose policy. It prioritises 323 reads over writes. This SMQ policy (vs MQ) offers the promise 324 of less memory utilization, improved performance and increased 325 adaptability in the face of changing workloads. 326 327config DM_WRITECACHE 328 tristate "Writecache target" 329 depends on BLK_DEV_DM 330 ---help--- 331 The writecache target caches writes on persistent memory or SSD. 332 It is intended for databases or other programs that need extremely 333 low commit latency. 334 335 The writecache target doesn't cache reads because reads are supposed 336 to be cached in standard RAM. 337 338config DM_ERA 339 tristate "Era target (EXPERIMENTAL)" 340 depends on BLK_DEV_DM 341 default n 342 select DM_PERSISTENT_DATA 343 select DM_BIO_PRISON 344 ---help--- 345 dm-era tracks which parts of a block device are written to 346 over time. Useful for maintaining cache coherency when using 347 vendor snapshots. 348 349config DM_MIRROR 350 tristate "Mirror target" 351 depends on BLK_DEV_DM 352 ---help--- 353 Allow volume managers to mirror logical volumes, also 354 needed for live data migration tools such as 'pvmove'. 355 356config DM_LOG_USERSPACE 357 tristate "Mirror userspace logging" 358 depends on DM_MIRROR && NET 359 select CONNECTOR 360 ---help--- 361 The userspace logging module provides a mechanism for 362 relaying the dm-dirty-log API to userspace. Log designs 363 which are more suited to userspace implementation (e.g. 364 shared storage logs) or experimental logs can be implemented 365 by leveraging this framework. 366 367config DM_RAID 368 tristate "RAID 1/4/5/6/10 target" 369 depends on BLK_DEV_DM 370 select MD_RAID0 371 select MD_RAID1 372 select MD_RAID10 373 select MD_RAID456 374 select BLK_DEV_MD 375 ---help--- 376 A dm target that supports RAID1, RAID10, RAID4, RAID5 and RAID6 mappings 377 378 A RAID-5 set of N drives with a capacity of C MB per drive provides 379 the capacity of C * (N - 1) MB, and protects against a failure 380 of a single drive. For a given sector (row) number, (N - 1) drives 381 contain data sectors, and one drive contains the parity protection. 382 For a RAID-4 set, the parity blocks are present on a single drive, 383 while a RAID-5 set distributes the parity across the drives in one 384 of the available parity distribution methods. 385 386 A RAID-6 set of N drives with a capacity of C MB per drive 387 provides the capacity of C * (N - 2) MB, and protects 388 against a failure of any two drives. For a given sector 389 (row) number, (N - 2) drives contain data sectors, and two 390 drives contains two independent redundancy syndromes. Like 391 RAID-5, RAID-6 distributes the syndromes across the drives 392 in one of the available parity distribution methods. 393 394config DM_ZERO 395 tristate "Zero target" 396 depends on BLK_DEV_DM 397 ---help--- 398 A target that discards writes, and returns all zeroes for 399 reads. Useful in some recovery situations. 400 401config DM_MULTIPATH 402 tristate "Multipath target" 403 depends on BLK_DEV_DM 404 # nasty syntax but means make DM_MULTIPATH independent 405 # of SCSI_DH if the latter isn't defined but if 406 # it is, DM_MULTIPATH must depend on it. We get a build 407 # error if SCSI_DH=m and DM_MULTIPATH=y 408 depends on !SCSI_DH || SCSI 409 ---help--- 410 Allow volume managers to support multipath hardware. 411 412config DM_MULTIPATH_QL 413 tristate "I/O Path Selector based on the number of in-flight I/Os" 414 depends on DM_MULTIPATH 415 ---help--- 416 This path selector is a dynamic load balancer which selects 417 the path with the least number of in-flight I/Os. 418 419 If unsure, say N. 420 421config DM_MULTIPATH_ST 422 tristate "I/O Path Selector based on the service time" 423 depends on DM_MULTIPATH 424 ---help--- 425 This path selector is a dynamic load balancer which selects 426 the path expected to complete the incoming I/O in the shortest 427 time. 428 429 If unsure, say N. 430 431config DM_DELAY 432 tristate "I/O delaying target" 433 depends on BLK_DEV_DM 434 ---help--- 435 A target that delays reads and/or writes and can send 436 them to different devices. Useful for testing. 437 438 If unsure, say N. 439 440config DM_DUST 441 tristate "Bad sector simulation target" 442 depends on BLK_DEV_DM 443 ---help--- 444 A target that simulates bad sector behavior. 445 Useful for testing. 446 447 If unsure, say N. 448 449config DM_INIT 450 bool "DM \"dm-mod.create=\" parameter support" 451 depends on BLK_DEV_DM=y 452 ---help--- 453 Enable "dm-mod.create=" parameter to create mapped devices at init time. 454 This option is useful to allow mounting rootfs without requiring an 455 initramfs. 456 See Documentation/device-mapper/dm-init.txt for dm-mod.create="..." 457 format. 458 459 If unsure, say N. 460 461config DM_UEVENT 462 bool "DM uevents" 463 depends on BLK_DEV_DM 464 ---help--- 465 Generate udev events for DM events. 466 467config DM_FLAKEY 468 tristate "Flakey target" 469 depends on BLK_DEV_DM 470 ---help--- 471 A target that intermittently fails I/O for debugging purposes. 472 473config DM_VERITY 474 tristate "Verity target support" 475 depends on BLK_DEV_DM 476 select CRYPTO 477 select CRYPTO_HASH 478 select DM_BUFIO 479 ---help--- 480 This device-mapper target creates a read-only device that 481 transparently validates the data on one underlying device against 482 a pre-generated tree of cryptographic checksums stored on a second 483 device. 484 485 You'll need to activate the digests you're going to use in the 486 cryptoapi configuration. 487 488 To compile this code as a module, choose M here: the module will 489 be called dm-verity. 490 491 If unsure, say N. 492 493config DM_VERITY_FEC 494 bool "Verity forward error correction support" 495 depends on DM_VERITY 496 select REED_SOLOMON 497 select REED_SOLOMON_DEC8 498 ---help--- 499 Add forward error correction support to dm-verity. This option 500 makes it possible to use pre-generated error correction data to 501 recover from corrupted blocks. 502 503 If unsure, say N. 504 505config DM_SWITCH 506 tristate "Switch target support (EXPERIMENTAL)" 507 depends on BLK_DEV_DM 508 ---help--- 509 This device-mapper target creates a device that supports an arbitrary 510 mapping of fixed-size regions of I/O across a fixed set of paths. 511 The path used for any specific region can be switched dynamically 512 by sending the target a message. 513 514 To compile this code as a module, choose M here: the module will 515 be called dm-switch. 516 517 If unsure, say N. 518 519config DM_LOG_WRITES 520 tristate "Log writes target support" 521 depends on BLK_DEV_DM 522 ---help--- 523 This device-mapper target takes two devices, one device to use 524 normally, one to log all write operations done to the first device. 525 This is for use by file system developers wishing to verify that 526 their fs is writing a consistent file system at all times by allowing 527 them to replay the log in a variety of ways and to check the 528 contents. 529 530 To compile this code as a module, choose M here: the module will 531 be called dm-log-writes. 532 533 If unsure, say N. 534 535config DM_INTEGRITY 536 tristate "Integrity target support" 537 depends on BLK_DEV_DM 538 select BLK_DEV_INTEGRITY 539 select DM_BUFIO 540 select CRYPTO 541 select ASYNC_XOR 542 ---help--- 543 This device-mapper target emulates a block device that has 544 additional per-sector tags that can be used for storing 545 integrity information. 546 547 This integrity target is used with the dm-crypt target to 548 provide authenticated disk encryption or it can be used 549 standalone. 550 551 To compile this code as a module, choose M here: the module will 552 be called dm-integrity. 553 554config DM_ZONED 555 tristate "Drive-managed zoned block device target support" 556 depends on BLK_DEV_DM 557 depends on BLK_DEV_ZONED 558 ---help--- 559 This device-mapper target takes a host-managed or host-aware zoned 560 block device and exposes most of its capacity as a regular block 561 device (drive-managed zoned block device) without any write 562 constraints. This is mainly intended for use with file systems that 563 do not natively support zoned block devices but still want to 564 benefit from the increased capacity offered by SMR disks. Other uses 565 by applications using raw block devices (for example object stores) 566 are also possible. 567 568 To compile this code as a module, choose M here: the module will 569 be called dm-zoned. 570 571 If unsure, say N. 572 573endif # MD 574