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			504 lines
		
	
	
		
			16 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
#
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# Block device driver configuration
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#
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menuconfig MD
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	bool "Multiple devices driver support (RAID and LVM)"
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	depends on BLOCK
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	select SRCU
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	help
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	  Support multiple physical spindles through a single logical device.
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	  Required for RAID and logical volume management.
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if MD
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config BLK_DEV_MD
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	tristate "RAID support"
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	---help---
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	  This driver lets you combine several hard disk partitions into one
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	  logical block device. This can be used to simply append one
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	  partition to another one or to combine several redundant hard disks
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	  into a RAID1/4/5 device so as to provide protection against hard
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	  disk failures. This is called "Software RAID" since the combining of
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	  the partitions is done by the kernel. "Hardware RAID" means that the
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	  combining is done by a dedicated controller; if you have such a
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	  controller, you do not need to say Y here.
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	  More information about Software RAID on Linux is contained in the
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	  Software RAID mini-HOWTO, available from
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	  <http://www.tldp.org/docs.html#howto>. There you will also learn
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	  where to get the supporting user space utilities raidtools.
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	  If unsure, say N.
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config MD_AUTODETECT
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	bool "Autodetect RAID arrays during kernel boot"
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	depends on BLK_DEV_MD=y
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	default y
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	---help---
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	  If you say Y here, then the kernel will try to autodetect raid
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	  arrays as part of its boot process. 
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	  If you don't use raid and say Y, this autodetection can cause 
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	  a several-second delay in the boot time due to various
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	  synchronisation steps that are part of this step.
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	  If unsure, say Y.
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config MD_LINEAR
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	tristate "Linear (append) mode"
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	depends on BLK_DEV_MD
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	---help---
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	  If you say Y here, then your multiple devices driver will be able to
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	  use the so-called linear mode, i.e. it will combine the hard disk
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	  partitions by simply appending one to the other.
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	  To compile this as a module, choose M here: the module
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	  will be called linear.
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	  If unsure, say Y.
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config MD_RAID0
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	tristate "RAID-0 (striping) mode"
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	depends on BLK_DEV_MD
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	---help---
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	  If you say Y here, then your multiple devices driver will be able to
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	  use the so-called raid0 mode, i.e. it will combine the hard disk
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	  partitions into one logical device in such a fashion as to fill them
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	  up evenly, one chunk here and one chunk there. This will increase
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	  the throughput rate if the partitions reside on distinct disks.
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	  Information about Software RAID on Linux is contained in the
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	  Software-RAID mini-HOWTO, available from
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	  <http://www.tldp.org/docs.html#howto>. There you will also
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	  learn where to get the supporting user space utilities raidtools.
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	  To compile this as a module, choose M here: the module
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	  will be called raid0.
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	  If unsure, say Y.
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config MD_RAID1
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	tristate "RAID-1 (mirroring) mode"
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	depends on BLK_DEV_MD
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	---help---
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	  A RAID-1 set consists of several disk drives which are exact copies
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	  of each other.  In the event of a mirror failure, the RAID driver
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	  will continue to use the operational mirrors in the set, providing
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	  an error free MD (multiple device) to the higher levels of the
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	  kernel.  In a set with N drives, the available space is the capacity
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	  of a single drive, and the set protects against a failure of (N - 1)
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	  drives.
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	  Information about Software RAID on Linux is contained in the
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	  Software-RAID mini-HOWTO, available from
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	  <http://www.tldp.org/docs.html#howto>.  There you will also
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	  learn where to get the supporting user space utilities raidtools.
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	  If you want to use such a RAID-1 set, say Y.  To compile this code
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	  as a module, choose M here: the module will be called raid1.
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	  If unsure, say Y.
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config MD_RAID10
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	tristate "RAID-10 (mirrored striping) mode"
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	depends on BLK_DEV_MD
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	---help---
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	  RAID-10 provides a combination of striping (RAID-0) and
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	  mirroring (RAID-1) with easier configuration and more flexible
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	  layout.
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	  Unlike RAID-0, but like RAID-1, RAID-10 requires all devices to
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	  be the same size (or at least, only as much as the smallest device
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	  will be used).
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	  RAID-10 provides a variety of layouts that provide different levels
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	  of redundancy and performance.
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	  RAID-10 requires mdadm-1.7.0 or later, available at:
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	  ftp://ftp.kernel.org/pub/linux/utils/raid/mdadm/
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	  If unsure, say Y.
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config MD_RAID456
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	tristate "RAID-4/RAID-5/RAID-6 mode"
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	depends on BLK_DEV_MD
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	select RAID6_PQ
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	select LIBCRC32C
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	select ASYNC_MEMCPY
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	select ASYNC_XOR
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	select ASYNC_PQ
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	select ASYNC_RAID6_RECOV
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	---help---
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	  A RAID-5 set of N drives with a capacity of C MB per drive provides
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	  the capacity of C * (N - 1) MB, and protects against a failure
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	  of a single drive. For a given sector (row) number, (N - 1) drives
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	  contain data sectors, and one drive contains the parity protection.
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	  For a RAID-4 set, the parity blocks are present on a single drive,
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	  while a RAID-5 set distributes the parity across the drives in one
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	  of the available parity distribution methods.
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	  A RAID-6 set of N drives with a capacity of C MB per drive
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	  provides the capacity of C * (N - 2) MB, and protects
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	  against a failure of any two drives. For a given sector
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	  (row) number, (N - 2) drives contain data sectors, and two
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	  drives contains two independent redundancy syndromes.  Like
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	  RAID-5, RAID-6 distributes the syndromes across the drives
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	  in one of the available parity distribution methods.
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	  Information about Software RAID on Linux is contained in the
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	  Software-RAID mini-HOWTO, available from
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	  <http://www.tldp.org/docs.html#howto>. There you will also
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	  learn where to get the supporting user space utilities raidtools.
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	  If you want to use such a RAID-4/RAID-5/RAID-6 set, say Y.  To
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	  compile this code as a module, choose M here: the module
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	  will be called raid456.
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	  If unsure, say Y.
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config MD_MULTIPATH
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	tristate "Multipath I/O support"
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	depends on BLK_DEV_MD
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	help
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	  MD_MULTIPATH provides a simple multi-path personality for use
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	  the MD framework.  It is not under active development.  New
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	  projects should consider using DM_MULTIPATH which has more
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	  features and more testing.
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	  If unsure, say N.
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config MD_FAULTY
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	tristate "Faulty test module for MD"
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	depends on BLK_DEV_MD
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	help
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	  The "faulty" module allows for a block device that occasionally returns
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	  read or write errors.  It is useful for testing.
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	  In unsure, say N.
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config MD_CLUSTER
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	tristate "Cluster Support for MD (EXPERIMENTAL)"
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	depends on BLK_DEV_MD
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	depends on DLM
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	default n
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	---help---
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	Clustering support for MD devices. This enables locking and
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	synchronization across multiple systems on the cluster, so all
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	nodes in the cluster can access the MD devices simultaneously.
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	This brings the redundancy (and uptime) of RAID levels across the
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	nodes of the cluster.
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	If unsure, say N.
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source "drivers/md/bcache/Kconfig"
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config BLK_DEV_DM_BUILTIN
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	bool
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config BLK_DEV_DM
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	tristate "Device mapper support"
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	select BLK_DEV_DM_BUILTIN
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	---help---
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	  Device-mapper is a low level volume manager.  It works by allowing
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	  people to specify mappings for ranges of logical sectors.  Various
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	  mapping types are available, in addition people may write their own
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	  modules containing custom mappings if they wish.
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	  Higher level volume managers such as LVM2 use this driver.
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	  To compile this as a module, choose M here: the module will be
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	  called dm-mod.
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	  If unsure, say N.
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config DM_MQ_DEFAULT
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	bool "request-based DM: use blk-mq I/O path by default"
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	depends on BLK_DEV_DM
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	---help---
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	  This option enables the blk-mq based I/O path for request-based
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	  DM devices by default.  With the option the dm_mod.use_blk_mq
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	  module/boot option defaults to Y, without it to N, but it can
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	  still be overriden either way.
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	  If unsure say N.
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config DM_DEBUG
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	bool "Device mapper debugging support"
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	depends on BLK_DEV_DM
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	---help---
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	  Enable this for messages that may help debug device-mapper problems.
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	  If unsure, say N.
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config DM_BUFIO
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       tristate
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       depends on BLK_DEV_DM
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       ---help---
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	 This interface allows you to do buffered I/O on a device and acts
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	 as a cache, holding recently-read blocks in memory and performing
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	 delayed writes.
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config DM_DEBUG_BLOCK_STACK_TRACING
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       bool "Keep stack trace of persistent data block lock holders"
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       depends on STACKTRACE_SUPPORT && DM_BUFIO
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       select STACKTRACE
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       ---help---
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	 Enable this for messages that may help debug problems with the
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	 block manager locking used by thin provisioning and caching.
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	 If unsure, say N.
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config DM_BIO_PRISON
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       tristate
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       depends on BLK_DEV_DM
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       ---help---
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	 Some bio locking schemes used by other device-mapper targets
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	 including thin provisioning.
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source "drivers/md/persistent-data/Kconfig"
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config DM_CRYPT
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	tristate "Crypt target support"
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	depends on BLK_DEV_DM
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	select CRYPTO
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	select CRYPTO_CBC
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	---help---
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	  This device-mapper target allows you to create a device that
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	  transparently encrypts the data on it. You'll need to activate
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	  the ciphers you're going to use in the cryptoapi configuration.
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	  For further information on dm-crypt and userspace tools see:
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	  <https://gitlab.com/cryptsetup/cryptsetup/wikis/DMCrypt>
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	  To compile this code as a module, choose M here: the module will
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	  be called dm-crypt.
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	  If unsure, say N.
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config DM_SNAPSHOT
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       tristate "Snapshot target"
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       depends on BLK_DEV_DM
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       select DM_BUFIO
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       ---help---
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         Allow volume managers to take writable snapshots of a device.
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config DM_THIN_PROVISIONING
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       tristate "Thin provisioning target"
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       depends on BLK_DEV_DM
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       select DM_PERSISTENT_DATA
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       select DM_BIO_PRISON
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       ---help---
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         Provides thin provisioning and snapshots that share a data store.
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config DM_CACHE
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       tristate "Cache target (EXPERIMENTAL)"
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       depends on BLK_DEV_DM
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       default n
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       select DM_PERSISTENT_DATA
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       select DM_BIO_PRISON
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       ---help---
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         dm-cache attempts to improve performance of a block device by
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         moving frequently used data to a smaller, higher performance
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         device.  Different 'policy' plugins can be used to change the
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         algorithms used to select which blocks are promoted, demoted,
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         cleaned etc.  It supports writeback and writethrough modes.
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config DM_CACHE_SMQ
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       tristate "Stochastic MQ Cache Policy (EXPERIMENTAL)"
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       depends on DM_CACHE
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       default y
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       ---help---
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         A cache policy that uses a multiqueue ordered by recent hits
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         to select which blocks should be promoted and demoted.
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         This is meant to be a general purpose policy.  It prioritises
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         reads over writes.  This SMQ policy (vs MQ) offers the promise
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         of less memory utilization, improved performance and increased
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         adaptability in the face of changing workloads.
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config DM_CACHE_CLEANER
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       tristate "Cleaner Cache Policy (EXPERIMENTAL)"
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       depends on DM_CACHE
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       default y
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       ---help---
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         A simple cache policy that writes back all data to the
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         origin.  Used when decommissioning a dm-cache.
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config DM_ERA
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       tristate "Era target (EXPERIMENTAL)"
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       depends on BLK_DEV_DM
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       default n
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       select DM_PERSISTENT_DATA
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       select DM_BIO_PRISON
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       ---help---
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         dm-era tracks which parts of a block device are written to
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         over time.  Useful for maintaining cache coherency when using
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         vendor snapshots.
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config DM_MIRROR
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       tristate "Mirror target"
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       depends on BLK_DEV_DM
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       ---help---
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         Allow volume managers to mirror logical volumes, also
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         needed for live data migration tools such as 'pvmove'.
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config DM_LOG_USERSPACE
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	tristate "Mirror userspace logging"
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	depends on DM_MIRROR && NET
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	select CONNECTOR
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	---help---
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	  The userspace logging module provides a mechanism for
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	  relaying the dm-dirty-log API to userspace.  Log designs
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	  which are more suited to userspace implementation (e.g.
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	  shared storage logs) or experimental logs can be implemented
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	  by leveraging this framework.
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config DM_RAID
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       tristate "RAID 1/4/5/6/10 target"
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       depends on BLK_DEV_DM
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       select MD_RAID1
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       select MD_RAID10
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       select MD_RAID456
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       select BLK_DEV_MD
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       ---help---
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	 A dm target that supports RAID1, RAID10, RAID4, RAID5 and RAID6 mappings
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	 A RAID-5 set of N drives with a capacity of C MB per drive provides
 | 
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	 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
 | 
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	 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
 | 
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	 drives contains two independent redundancy syndromes.  Like
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	 RAID-5, RAID-6 distributes the syndromes across the drives
 | 
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	 in one of the available parity distribution methods.
 | 
						|
 | 
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config DM_ZERO
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	tristate "Zero target"
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	depends on BLK_DEV_DM
 | 
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	---help---
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	  A target that discards writes, and returns all zeroes for
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	  reads.  Useful in some recovery situations.
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config DM_MULTIPATH
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	tristate "Multipath target"
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	depends on BLK_DEV_DM
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	# nasty syntax but means make DM_MULTIPATH independent
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	# of SCSI_DH if the latter isn't defined but if
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	# it is, DM_MULTIPATH must depend on it.  We get a build
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	# error if SCSI_DH=m and DM_MULTIPATH=y
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	depends on !SCSI_DH || SCSI
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	---help---
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	  Allow volume managers to support multipath hardware.
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config DM_MULTIPATH_QL
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	tristate "I/O Path Selector based on the number of in-flight I/Os"
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	depends on DM_MULTIPATH
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	---help---
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	  This path selector is a dynamic load balancer which selects
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	  the path with the least number of in-flight I/Os.
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	  If unsure, say N.
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 | 
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config DM_MULTIPATH_ST
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	tristate "I/O Path Selector based on the service time"
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	depends on DM_MULTIPATH
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						|
	---help---
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	  This path selector is a dynamic load balancer which selects
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	  the path expected to complete the incoming I/O in the shortest
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	  time.
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						|
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	  If unsure, say N.
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						|
 | 
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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_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_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.
 | 
						|
 | 
						|
endif # MD
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