| # SPDX-License-Identifier: GPL-2.0-only |
| # |
| # Block device driver configuration |
| # |
| |
| menuconfig MD |
| bool "Multiple devices driver support (RAID and LVM)" |
| depends on BLOCK |
| select SRCU |
| help |
| Support multiple physical spindles through a single logical device. |
| Required for RAID and logical volume management. |
| |
| if MD |
| |
| config BLK_DEV_MD |
| tristate "RAID support" |
| help |
| This driver lets you combine several hard disk partitions into one |
| logical block device. This can be used to simply append one |
| partition to another one or to combine several redundant hard disks |
| into a RAID1/4/5 device so as to provide protection against hard |
| disk failures. This is called "Software RAID" since the combining of |
| the partitions is done by the kernel. "Hardware RAID" means that the |
| combining is done by a dedicated controller; if you have such a |
| controller, you do not need to say Y here. |
| |
| More information about Software RAID on Linux is contained in the |
| Software RAID mini-HOWTO, available from |
| <https://www.tldp.org/docs.html#howto>. There you will also learn |
| where to get the supporting user space utilities raidtools. |
| |
| If unsure, say N. |
| |
| config MD_AUTODETECT |
| bool "Autodetect RAID arrays during kernel boot" |
| depends on BLK_DEV_MD=y |
| default y |
| help |
| If you say Y here, then the kernel will try to autodetect raid |
| arrays as part of its boot process. |
| |
| If you don't use raid and say Y, this autodetection can cause |
| a several-second delay in the boot time due to various |
| synchronisation steps that are part of this step. |
| |
| If unsure, say Y. |
| |
| config MD_LINEAR |
| tristate "Linear (append) mode" |
| depends on BLK_DEV_MD |
| help |
| If you say Y here, then your multiple devices driver will be able to |
| use the so-called linear mode, i.e. it will combine the hard disk |
| partitions by simply appending one to the other. |
| |
| To compile this as a module, choose M here: the module |
| will be called linear. |
| |
| If unsure, say Y. |
| |
| config MD_RAID0 |
| tristate "RAID-0 (striping) mode" |
| depends on BLK_DEV_MD |
| help |
| If you say Y here, then your multiple devices driver will be able to |
| use the so-called raid0 mode, i.e. it will combine the hard disk |
| partitions into one logical device in such a fashion as to fill them |
| up evenly, one chunk here and one chunk there. This will increase |
| the throughput rate if the partitions reside on distinct disks. |
| |
| Information about Software RAID on Linux is contained in the |
| Software-RAID mini-HOWTO, available from |
| <https://www.tldp.org/docs.html#howto>. There you will also |
| learn where to get the supporting user space utilities raidtools. |
| |
| To compile this as a module, choose M here: the module |
| will be called raid0. |
| |
| If unsure, say Y. |
| |
| config MD_RAID1 |
| tristate "RAID-1 (mirroring) mode" |
| depends on BLK_DEV_MD |
| help |
| A RAID-1 set consists of several disk drives which are exact copies |
| of each other. In the event of a mirror failure, the RAID driver |
| will continue to use the operational mirrors in the set, providing |
| an error free MD (multiple device) to the higher levels of the |
| kernel. In a set with N drives, the available space is the capacity |
| of a single drive, and the set protects against a failure of (N - 1) |
| drives. |
| |
| Information about Software RAID on Linux is contained in the |
| Software-RAID mini-HOWTO, available from |
| <https://www.tldp.org/docs.html#howto>. There you will also |
| learn where to get the supporting user space utilities raidtools. |
| |
| If you want to use such a RAID-1 set, say Y. To compile this code |
| as a module, choose M here: the module will be called raid1. |
| |
| If unsure, say Y. |
| |
| config MD_RAID10 |
| tristate "RAID-10 (mirrored striping) mode" |
| depends on BLK_DEV_MD |
| help |
| RAID-10 provides a combination of striping (RAID-0) and |
| mirroring (RAID-1) with easier configuration and more flexible |
| layout. |
| Unlike RAID-0, but like RAID-1, RAID-10 requires all devices to |
| be the same size (or at least, only as much as the smallest device |
| will be used). |
| RAID-10 provides a variety of layouts that provide different levels |
| of redundancy and performance. |
| |
| RAID-10 requires mdadm-1.7.0 or later, available at: |
| |
| https://www.kernel.org/pub/linux/utils/raid/mdadm/ |
| |
| If unsure, say Y. |
| |
| config MD_RAID456 |
| tristate "RAID-4/RAID-5/RAID-6 mode" |
| depends on BLK_DEV_MD |
| select RAID6_PQ |
| select LIBCRC32C |
| select ASYNC_MEMCPY |
| select ASYNC_XOR |
| select ASYNC_PQ |
| select ASYNC_RAID6_RECOV |
| help |
| A RAID-5 set of N drives with a capacity of C MB per drive provides |
| the capacity of C * (N - 1) MB, and protects against a failure |
| of a single drive. For a given sector (row) number, (N - 1) drives |
| contain data sectors, and one drive contains the parity protection. |
| For a RAID-4 set, the parity blocks are present on a single drive, |
| while a RAID-5 set distributes the parity across the drives in one |
| of the available parity distribution methods. |
| |
| A RAID-6 set of N drives with a capacity of C MB per drive |
| provides the capacity of C * (N - 2) MB, and protects |
| against a failure of any two drives. For a given sector |
| (row) number, (N - 2) drives contain data sectors, and two |
| drives contains two independent redundancy syndromes. Like |
| RAID-5, RAID-6 distributes the syndromes across the drives |
| in one of the available parity distribution methods. |
| |
| Information about Software RAID on Linux is contained in the |
| Software-RAID mini-HOWTO, available from |
| <https://www.tldp.org/docs.html#howto>. There you will also |
| learn where to get the supporting user space utilities raidtools. |
| |
| If you want to use such a RAID-4/RAID-5/RAID-6 set, say Y. To |
| compile this code as a module, choose M here: the module |
| will be called raid456. |
| |
| If unsure, say Y. |
| |
| config MD_MULTIPATH |
| tristate "Multipath I/O support" |
| depends on BLK_DEV_MD |
| help |
| MD_MULTIPATH provides a simple multi-path personality for use |
| the MD framework. It is not under active development. New |
| projects should consider using DM_MULTIPATH which has more |
| features and more testing. |
| |
| If unsure, say N. |
| |
| config MD_FAULTY |
| tristate "Faulty test module for MD" |
| depends on BLK_DEV_MD |
| help |
| The "faulty" module allows for a block device that occasionally returns |
| read or write errors. It is useful for testing. |
| |
| In unsure, say N. |
| |
| |
| config MD_CLUSTER |
| tristate "Cluster Support for MD" |
| depends on BLK_DEV_MD |
| depends on DLM |
| default n |
| help |
| Clustering support for MD devices. This enables locking and |
| synchronization across multiple systems on the cluster, so all |
| nodes in the cluster can access the MD devices simultaneously. |
| |
| This brings the redundancy (and uptime) of RAID levels across the |
| nodes of the cluster. Currently, it can work with raid1 and raid10 |
| (limited support). |
| |
| If unsure, say N. |
| |
| source "drivers/md/bcache/Kconfig" |
| |
| config BLK_DEV_DM_BUILTIN |
| bool |
| |
| config BLK_DEV_DM |
| tristate "Device mapper support" |
| select BLK_DEV_DM_BUILTIN |
| depends on DAX || DAX=n |
| help |
| Device-mapper is a low level volume manager. It works by allowing |
| people to specify mappings for ranges of logical sectors. Various |
| mapping types are available, in addition people may write their own |
| modules containing custom mappings if they wish. |
| |
| Higher level volume managers such as LVM2 use this driver. |
| |
| To compile this as a module, choose M here: the module will be |
| called dm-mod. |
| |
| If unsure, say N. |
| |
| config DM_DEBUG |
| bool "Device mapper debugging support" |
| depends on BLK_DEV_DM |
| help |
| Enable this for messages that may help debug device-mapper problems. |
| |
| If unsure, say N. |
| |
| config DM_BUFIO |
| tristate |
| depends on BLK_DEV_DM |
| help |
| This interface allows you to do buffered I/O on a device and acts |
| as a cache, holding recently-read blocks in memory and performing |
| delayed writes. |
| |
| config DM_DEBUG_BLOCK_MANAGER_LOCKING |
| bool "Block manager locking" |
| depends on DM_BUFIO |
| help |
| Block manager locking can catch various metadata corruption issues. |
| |
| If unsure, say N. |
| |
| config DM_DEBUG_BLOCK_STACK_TRACING |
| bool "Keep stack trace of persistent data block lock holders" |
| depends on STACKTRACE_SUPPORT && DM_DEBUG_BLOCK_MANAGER_LOCKING |
| select STACKTRACE |
| help |
| Enable this for messages that may help debug problems with the |
| block manager locking used by thin provisioning and caching. |
| |
| If unsure, say N. |
| |
| config DM_BIO_PRISON |
| tristate |
| depends on BLK_DEV_DM |
| help |
| Some bio locking schemes used by other device-mapper targets |
| including thin provisioning. |
| |
| source "drivers/md/persistent-data/Kconfig" |
| |
| config DM_UNSTRIPED |
| tristate "Unstriped target" |
| depends on BLK_DEV_DM |
| help |
| Unstripes I/O so it is issued solely on a single drive in a HW |
| RAID0 or dm-striped target. |
| |
| config DM_CRYPT |
| tristate "Crypt target support" |
| depends on BLK_DEV_DM |
| depends on (ENCRYPTED_KEYS || ENCRYPTED_KEYS=n) |
| select CRYPTO |
| select CRYPTO_CBC |
| select CRYPTO_ESSIV |
| help |
| This device-mapper target allows you to create a device that |
| transparently encrypts the data on it. You'll need to activate |
| the ciphers you're going to use in the cryptoapi configuration. |
| |
| For further information on dm-crypt and userspace tools see: |
| <https://gitlab.com/cryptsetup/cryptsetup/wikis/DMCrypt> |
| |
| To compile this code as a module, choose M here: the module will |
| be called dm-crypt. |
| |
| If unsure, say N. |
| |
| config DM_SNAPSHOT |
| tristate "Snapshot target" |
| depends on BLK_DEV_DM |
| select DM_BUFIO |
| help |
| Allow volume managers to take writable snapshots of a device. |
| |
| config DM_THIN_PROVISIONING |
| tristate "Thin provisioning target" |
| depends on BLK_DEV_DM |
| select DM_PERSISTENT_DATA |
| select DM_BIO_PRISON |
| help |
| Provides thin provisioning and snapshots that share a data store. |
| |
| config DM_CACHE |
| tristate "Cache target (EXPERIMENTAL)" |
| depends on BLK_DEV_DM |
| default n |
| select DM_PERSISTENT_DATA |
| select DM_BIO_PRISON |
| help |
| dm-cache attempts to improve performance of a block device by |
| moving frequently used data to a smaller, higher performance |
| device. Different 'policy' plugins can be used to change the |
| algorithms used to select which blocks are promoted, demoted, |
| cleaned etc. It supports writeback and writethrough modes. |
| |
| config DM_CACHE_SMQ |
| tristate "Stochastic MQ Cache Policy (EXPERIMENTAL)" |
| depends on DM_CACHE |
| default y |
| help |
| A cache policy that uses a multiqueue ordered by recent hits |
| to select which blocks should be promoted and demoted. |
| This is meant to be a general purpose policy. It prioritises |
| reads over writes. This SMQ policy (vs MQ) offers the promise |
| of less memory utilization, improved performance and increased |
| adaptability in the face of changing workloads. |
| |
| config DM_WRITECACHE |
| tristate "Writecache target" |
| depends on BLK_DEV_DM |
| help |
| The writecache target caches writes on persistent memory or SSD. |
| It is intended for databases or other programs that need extremely |
| low commit latency. |
| |
| The writecache target doesn't cache reads because reads are supposed |
| to be cached in standard RAM. |
| |
| config DM_EBS |
| tristate "Emulated block size target (EXPERIMENTAL)" |
| depends on BLK_DEV_DM |
| select DM_BUFIO |
| help |
| dm-ebs emulates smaller logical block size on backing devices |
| with larger ones (e.g. 512 byte sectors on 4K native disks). |
| |
| config DM_ERA |
| tristate "Era target (EXPERIMENTAL)" |
| depends on BLK_DEV_DM |
| default n |
| select DM_PERSISTENT_DATA |
| select DM_BIO_PRISON |
| help |
| dm-era tracks which parts of a block device are written to |
| over time. Useful for maintaining cache coherency when using |
| vendor snapshots. |
| |
| config DM_CLONE |
| tristate "Clone target (EXPERIMENTAL)" |
| depends on BLK_DEV_DM |
| default n |
| select DM_PERSISTENT_DATA |
| help |
| dm-clone produces a one-to-one copy of an existing, read-only source |
| device into a writable destination device. The cloned device is |
| visible/mountable immediately and the copy of the source device to the |
| destination device happens in the background, in parallel with user |
| I/O. |
| |
| If unsure, say N. |
| |
| config DM_MIRROR |
| tristate "Mirror target" |
| depends on BLK_DEV_DM |
| help |
| Allow volume managers to mirror logical volumes, also |
| needed for live data migration tools such as 'pvmove'. |
| |
| config DM_LOG_USERSPACE |
| tristate "Mirror userspace logging" |
| depends on DM_MIRROR && NET |
| select CONNECTOR |
| help |
| The userspace logging module provides a mechanism for |
| relaying the dm-dirty-log API to userspace. Log designs |
| which are more suited to userspace implementation (e.g. |
| shared storage logs) or experimental logs can be implemented |
| by leveraging this framework. |
| |
| config DM_RAID |
| tristate "RAID 1/4/5/6/10 target" |
| depends on BLK_DEV_DM |
| select MD_RAID0 |
| select MD_RAID1 |
| select MD_RAID10 |
| select MD_RAID456 |
| select BLK_DEV_MD |
| help |
| A dm target that supports RAID1, RAID10, RAID4, RAID5 and RAID6 mappings |
| |
| A RAID-5 set of N drives with a capacity of C MB per drive provides |
| the capacity of C * (N - 1) MB, and protects against a failure |
| of a single drive. For a given sector (row) number, (N - 1) drives |
| contain data sectors, and one drive contains the parity protection. |
| For a RAID-4 set, the parity blocks are present on a single drive, |
| while a RAID-5 set distributes the parity across the drives in one |
| of the available parity distribution methods. |
| |
| A RAID-6 set of N drives with a capacity of C MB per drive |
| provides the capacity of C * (N - 2) MB, and protects |
| against a failure of any two drives. For a given sector |
| (row) number, (N - 2) drives contain data sectors, and two |
| drives contains two independent redundancy syndromes. Like |
| RAID-5, RAID-6 distributes the syndromes across the drives |
| in one of the available parity distribution methods. |
| |
| config DM_ZERO |
| tristate "Zero target" |
| depends on BLK_DEV_DM |
| help |
| A target that discards writes, and returns all zeroes for |
| reads. Useful in some recovery situations. |
| |
| config DM_MULTIPATH |
| tristate "Multipath target" |
| depends on BLK_DEV_DM |
| # nasty syntax but means make DM_MULTIPATH independent |
| # of SCSI_DH if the latter isn't defined but if |
| # it is, DM_MULTIPATH must depend on it. We get a build |
| # error if SCSI_DH=m and DM_MULTIPATH=y |
| depends on !SCSI_DH || SCSI |
| help |
| Allow volume managers to support multipath hardware. |
| |
| config DM_MULTIPATH_QL |
| tristate "I/O Path Selector based on the number of in-flight I/Os" |
| depends on DM_MULTIPATH |
| help |
| This path selector is a dynamic load balancer which selects |
| the path with the least number of in-flight I/Os. |
| |
| If unsure, say N. |
| |
| config DM_MULTIPATH_ST |
| tristate "I/O Path Selector based on the service time" |
| depends on DM_MULTIPATH |
| help |
| This path selector is a dynamic load balancer which selects |
| the path expected to complete the incoming I/O in the shortest |
| time. |
| |
| If unsure, say N. |
| |
| config DM_MULTIPATH_HST |
| tristate "I/O Path Selector based on historical service time" |
| depends on DM_MULTIPATH |
| help |
| This path selector is a dynamic load balancer which selects |
| the path expected to complete the incoming I/O in the shortest |
| time by comparing estimated service time (based on historical |
| service time). |
| |
| If unsure, say N. |
| |
| config DM_DELAY |
| tristate "I/O delaying target" |
| depends on BLK_DEV_DM |
| help |
| A target that delays reads and/or writes and can send |
| them to different devices. Useful for testing. |
| |
| If unsure, say N. |
| |
| config DM_DUST |
| tristate "Bad sector simulation target" |
| depends on BLK_DEV_DM |
| help |
| A target that simulates bad sector behavior. |
| Useful for testing. |
| |
| If unsure, say N. |
| |
| config DM_INIT |
| bool "DM \"dm-mod.create=\" parameter support" |
| depends on BLK_DEV_DM=y |
| help |
| Enable "dm-mod.create=" parameter to create mapped devices at init time. |
| This option is useful to allow mounting rootfs without requiring an |
| initramfs. |
| See Documentation/admin-guide/device-mapper/dm-init.rst for dm-mod.create="..." |
| format. |
| |
| If unsure, say N. |
| |
| config DM_UEVENT |
| bool "DM uevents" |
| depends on BLK_DEV_DM |
| help |
| Generate udev events for DM events. |
| |
| config DM_FLAKEY |
| tristate "Flakey target" |
| depends on BLK_DEV_DM |
| help |
| A target that intermittently fails I/O for debugging purposes. |
| |
| config DM_VERITY |
| tristate "Verity target support" |
| depends on BLK_DEV_DM |
| select CRYPTO |
| select CRYPTO_HASH |
| select DM_BUFIO |
| help |
| This device-mapper target creates a read-only device that |
| transparently validates the data on one underlying device against |
| a pre-generated tree of cryptographic checksums stored on a second |
| device. |
| |
| You'll need to activate the digests you're going to use in the |
| cryptoapi configuration. |
| |
| To compile this code as a module, choose M here: the module will |
| be called dm-verity. |
| |
| If unsure, say N. |
| |
| config DM_VERITY_VERIFY_ROOTHASH_SIG |
| def_bool n |
| bool "Verity data device root hash signature verification support" |
| depends on DM_VERITY |
| select SYSTEM_DATA_VERIFICATION |
| help |
| Add ability for dm-verity device to be validated if the |
| pre-generated tree of cryptographic checksums passed has a pkcs#7 |
| signature file that can validate the roothash of the tree. |
| |
| If unsure, say N. |
| |
| config DM_VERITY_FEC |
| bool "Verity forward error correction support" |
| depends on DM_VERITY |
| select REED_SOLOMON |
| select REED_SOLOMON_DEC8 |
| help |
| Add forward error correction support to dm-verity. This option |
| makes it possible to use pre-generated error correction data to |
| recover from corrupted blocks. |
| |
| If unsure, say N. |
| |
| config DM_SWITCH |
| tristate "Switch target support (EXPERIMENTAL)" |
| depends on BLK_DEV_DM |
| help |
| This device-mapper target creates a device that supports an arbitrary |
| mapping of fixed-size regions of I/O across a fixed set of paths. |
| The path used for any specific region can be switched dynamically |
| by sending the target a message. |
| |
| To compile this code as a module, choose M here: the module will |
| be called dm-switch. |
| |
| If unsure, say N. |
| |
| config DM_LOG_WRITES |
| tristate "Log writes target support" |
| depends on BLK_DEV_DM |
| help |
| This device-mapper target takes two devices, one device to use |
| normally, one to log all write operations done to the first device. |
| This is for use by file system developers wishing to verify that |
| their fs is writing a consistent file system at all times by allowing |
| them to replay the log in a variety of ways and to check the |
| contents. |
| |
| To compile this code as a module, choose M here: the module will |
| be called dm-log-writes. |
| |
| If unsure, say N. |
| |
| config DM_INTEGRITY |
| tristate "Integrity target support" |
| depends on BLK_DEV_DM |
| select BLK_DEV_INTEGRITY |
| select DM_BUFIO |
| select CRYPTO |
| select ASYNC_XOR |
| help |
| This device-mapper target emulates a block device that has |
| additional per-sector tags that can be used for storing |
| integrity information. |
| |
| This integrity target is used with the dm-crypt target to |
| provide authenticated disk encryption or it can be used |
| standalone. |
| |
| To compile this code as a module, choose M here: the module will |
| be called dm-integrity. |
| |
| config DM_ZONED |
| tristate "Drive-managed zoned block device target support" |
| depends on BLK_DEV_DM |
| depends on BLK_DEV_ZONED |
| help |
| This device-mapper target takes a host-managed or host-aware zoned |
| block device and exposes most of its capacity as a regular block |
| device (drive-managed zoned block device) without any write |
| constraints. This is mainly intended for use with file systems that |
| do not natively support zoned block devices but still want to |
| benefit from the increased capacity offered by SMR disks. Other uses |
| by applications using raw block devices (for example object stores) |
| are also possible. |
| |
| To compile this code as a module, choose M here: the module will |
| be called dm-zoned. |
| |
| If unsure, say N. |
| |
| endif # MD |
