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The blockdev book basically contains user-faced documentation. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
472 lines
16 KiB
Plaintext
472 lines
16 KiB
Plaintext
# SPDX-License-Identifier: GPL-2.0
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#
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# Block device driver configuration
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#
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menuconfig BLK_DEV
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bool "Block devices"
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depends on BLOCK
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default y
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---help---
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Say Y here to get to see options for various different block device
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drivers. This option alone does not add any kernel code.
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If you say N, all options in this submenu will be skipped and disabled;
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only do this if you know what you are doing.
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if BLK_DEV
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config BLK_DEV_NULL_BLK
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tristate "Null test block driver"
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select CONFIGFS_FS
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config BLK_DEV_NULL_BLK_FAULT_INJECTION
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bool "Support fault injection for Null test block driver"
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depends on BLK_DEV_NULL_BLK && FAULT_INJECTION
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config BLK_DEV_FD
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tristate "Normal floppy disk support"
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depends on ARCH_MAY_HAVE_PC_FDC
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---help---
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If you want to use the floppy disk drive(s) of your PC under Linux,
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say Y. Information about this driver, especially important for IBM
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Thinkpad users, is contained in
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<file:Documentation/admin-guide/blockdev/floppy.rst>.
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That file also contains the location of the Floppy driver FAQ as
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well as location of the fdutils package used to configure additional
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parameters of the driver at run time.
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To compile this driver as a module, choose M here: the
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module will be called floppy.
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config AMIGA_FLOPPY
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tristate "Amiga floppy support"
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depends on AMIGA
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config ATARI_FLOPPY
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tristate "Atari floppy support"
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depends on ATARI
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config MAC_FLOPPY
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tristate "Support for PowerMac floppy"
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depends on PPC_PMAC && !PPC_PMAC64
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help
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If you have a SWIM-3 (Super Woz Integrated Machine 3; from Apple)
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floppy controller, say Y here. Most commonly found in PowerMacs.
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config BLK_DEV_SWIM
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tristate "Support for SWIM Macintosh floppy"
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depends on M68K && MAC
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help
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You should select this option if you want floppy support
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and you don't have a II, IIfx, Q900, Q950 or AV series.
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config AMIGA_Z2RAM
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tristate "Amiga Zorro II ramdisk support"
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depends on ZORRO
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help
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This enables support for using Chip RAM and Zorro II RAM as a
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ramdisk or as a swap partition. Say Y if you want to include this
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driver in the kernel.
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To compile this driver as a module, choose M here: the
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module will be called z2ram.
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config CDROM
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tristate
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select BLK_SCSI_REQUEST
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config GDROM
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tristate "SEGA Dreamcast GD-ROM drive"
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depends on SH_DREAMCAST
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select CDROM
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help
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A standard SEGA Dreamcast comes with a modified CD ROM drive called a
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"GD-ROM" by SEGA to signify it is capable of reading special disks
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with up to 1 GB of data. This drive will also read standard CD ROM
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disks. Select this option to access any disks in your GD ROM drive.
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Most users will want to say "Y" here.
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You can also build this as a module which will be called gdrom.
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config PARIDE
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tristate "Parallel port IDE device support"
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depends on PARPORT_PC
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---help---
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There are many external CD-ROM and disk devices that connect through
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your computer's parallel port. Most of them are actually IDE devices
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using a parallel port IDE adapter. This option enables the PARIDE
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subsystem which contains drivers for many of these external drives.
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Read <file:Documentation/admin-guide/blockdev/paride.rst> for more information.
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If you have said Y to the "Parallel-port support" configuration
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option, you may share a single port between your printer and other
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parallel port devices. Answer Y to build PARIDE support into your
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kernel, or M if you would like to build it as a loadable module. If
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your parallel port support is in a loadable module, you must build
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PARIDE as a module. If you built PARIDE support into your kernel,
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you may still build the individual protocol modules and high-level
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drivers as loadable modules. If you build this support as a module,
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it will be called paride.
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To use the PARIDE support, you must say Y or M here and also to at
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least one high-level driver (e.g. "Parallel port IDE disks",
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"Parallel port ATAPI CD-ROMs", "Parallel port ATAPI disks" etc.) and
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to at least one protocol driver (e.g. "ATEN EH-100 protocol",
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"MicroSolutions backpack protocol", "DataStor Commuter protocol"
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etc.).
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source "drivers/block/paride/Kconfig"
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source "drivers/block/mtip32xx/Kconfig"
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source "drivers/block/zram/Kconfig"
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config BLK_DEV_UMEM
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tristate "Micro Memory MM5415 Battery Backed RAM support"
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depends on PCI
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---help---
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Saying Y here will include support for the MM5415 family of
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battery backed (Non-volatile) RAM cards.
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<http://www.umem.com/>
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The cards appear as block devices that can be partitioned into
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as many as 15 partitions.
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To compile this driver as a module, choose M here: the
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module will be called umem.
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The umem driver has not yet been allocated a MAJOR number, so
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one is chosen dynamically.
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config BLK_DEV_UBD
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bool "Virtual block device"
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depends on UML
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---help---
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The User-Mode Linux port includes a driver called UBD which will let
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you access arbitrary files on the host computer as block devices.
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Unless you know that you do not need such virtual block devices say
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Y here.
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config BLK_DEV_UBD_SYNC
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bool "Always do synchronous disk IO for UBD"
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depends on BLK_DEV_UBD
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---help---
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Writes to the virtual block device are not immediately written to the
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host's disk; this may cause problems if, for example, the User-Mode
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Linux 'Virtual Machine' uses a journalling filesystem and the host
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computer crashes.
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Synchronous operation (i.e. always writing data to the host's disk
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immediately) is configurable on a per-UBD basis by using a special
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kernel command line option. Alternatively, you can say Y here to
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turn on synchronous operation by default for all block devices.
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If you're running a journalling file system (like reiserfs, for
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example) in your virtual machine, you will want to say Y here. If
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you care for the safety of the data in your virtual machine, Y is a
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wise choice too. In all other cases (for example, if you're just
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playing around with User-Mode Linux) you can choose N.
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config BLK_DEV_COW_COMMON
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bool
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default BLK_DEV_UBD
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config BLK_DEV_LOOP
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tristate "Loopback device support"
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---help---
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Saying Y here will allow you to use a regular file as a block
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device; you can then create a file system on that block device and
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mount it just as you would mount other block devices such as hard
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drive partitions, CD-ROM drives or floppy drives. The loop devices
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are block special device files with major number 7 and typically
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called /dev/loop0, /dev/loop1 etc.
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This is useful if you want to check an ISO 9660 file system before
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burning the CD, or if you want to use floppy images without first
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writing them to floppy. Furthermore, some Linux distributions avoid
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the need for a dedicated Linux partition by keeping their complete
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root file system inside a DOS FAT file using this loop device
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driver.
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To use the loop device, you need the losetup utility, found in the
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util-linux package, see
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<https://www.kernel.org/pub/linux/utils/util-linux/>.
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The loop device driver can also be used to "hide" a file system in
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a disk partition, floppy, or regular file, either using encryption
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(scrambling the data) or steganography (hiding the data in the low
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bits of, say, a sound file). This is also safe if the file resides
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on a remote file server.
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There are several ways of encrypting disks. Some of these require
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kernel patches. The vanilla kernel offers the cryptoloop option
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and a Device Mapper target (which is superior, as it supports all
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file systems). If you want to use the cryptoloop, say Y to both
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LOOP and CRYPTOLOOP, and make sure you have a recent (version 2.12
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or later) version of util-linux. Additionally, be aware that
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the cryptoloop is not safe for storing journaled filesystems.
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Note that this loop device has nothing to do with the loopback
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device used for network connections from the machine to itself.
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To compile this driver as a module, choose M here: the
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module will be called loop.
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Most users will answer N here.
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config BLK_DEV_LOOP_MIN_COUNT
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int "Number of loop devices to pre-create at init time"
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depends on BLK_DEV_LOOP
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default 8
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help
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Static number of loop devices to be unconditionally pre-created
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at init time.
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This default value can be overwritten on the kernel command
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line or with module-parameter loop.max_loop.
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The historic default is 8. If a late 2011 version of losetup(8)
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is used, it can be set to 0, since needed loop devices can be
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dynamically allocated with the /dev/loop-control interface.
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config BLK_DEV_CRYPTOLOOP
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tristate "Cryptoloop Support"
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select CRYPTO
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select CRYPTO_CBC
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depends on BLK_DEV_LOOP
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---help---
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Say Y here if you want to be able to use the ciphers that are
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provided by the CryptoAPI as loop transformation. This might be
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used as hard disk encryption.
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WARNING: This device is not safe for journaled file systems like
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ext3 or Reiserfs. Please use the Device Mapper crypto module
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instead, which can be configured to be on-disk compatible with the
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cryptoloop device.
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source "drivers/block/drbd/Kconfig"
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config BLK_DEV_NBD
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tristate "Network block device support"
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depends on NET
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---help---
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Saying Y here will allow your computer to be a client for network
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block devices, i.e. it will be able to use block devices exported by
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servers (mount file systems on them etc.). Communication between
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client and server works over TCP/IP networking, but to the client
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program this is hidden: it looks like a regular local file access to
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a block device special file such as /dev/nd0.
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Network block devices also allows you to run a block-device in
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userland (making server and client physically the same computer,
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communicating using the loopback network device).
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Read <file:Documentation/admin-guide/blockdev/nbd.rst> for more information,
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especially about where to find the server code, which runs in user
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space and does not need special kernel support.
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Note that this has nothing to do with the network file systems NFS
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or Coda; you can say N here even if you intend to use NFS or Coda.
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To compile this driver as a module, choose M here: the
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module will be called nbd.
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If unsure, say N.
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config BLK_DEV_SKD
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tristate "STEC S1120 Block Driver"
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depends on PCI
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depends on 64BIT
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---help---
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Saying Y or M here will enable support for the
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STEC, Inc. S1120 PCIe SSD.
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Use device /dev/skd$N amd /dev/skd$Np$M.
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config BLK_DEV_SX8
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tristate "Promise SATA SX8 support"
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depends on PCI
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---help---
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Saying Y or M here will enable support for the
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Promise SATA SX8 controllers.
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Use devices /dev/sx8/$N and /dev/sx8/$Np$M.
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config BLK_DEV_RAM
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tristate "RAM block device support"
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---help---
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Saying Y here will allow you to use a portion of your RAM memory as
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a block device, so that you can make file systems on it, read and
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write to it and do all the other things that you can do with normal
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block devices (such as hard drives). It is usually used to load and
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store a copy of a minimal root file system off of a floppy into RAM
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during the initial install of Linux.
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Note that the kernel command line option "ramdisk=XX" is now obsolete.
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For details, read <file:Documentation/admin-guide/blockdev/ramdisk.rst>.
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To compile this driver as a module, choose M here: the
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module will be called brd. An alias "rd" has been defined
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for historical reasons.
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Most normal users won't need the RAM disk functionality, and can
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thus say N here.
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config BLK_DEV_RAM_COUNT
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int "Default number of RAM disks"
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default "16"
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depends on BLK_DEV_RAM
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help
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The default value is 16 RAM disks. Change this if you know what you
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are doing. If you boot from a filesystem that needs to be extracted
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in memory, you will need at least one RAM disk (e.g. root on cramfs).
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config BLK_DEV_RAM_SIZE
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int "Default RAM disk size (kbytes)"
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depends on BLK_DEV_RAM
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default "4096"
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help
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The default value is 4096 kilobytes. Only change this if you know
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what you are doing.
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config CDROM_PKTCDVD
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tristate "Packet writing on CD/DVD media (DEPRECATED)"
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depends on !UML
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select CDROM
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select BLK_SCSI_REQUEST
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help
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Note: This driver is deprecated and will be removed from the
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kernel in the near future!
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If you have a CDROM/DVD drive that supports packet writing, say
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Y to include support. It should work with any MMC/Mt Fuji
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compliant ATAPI or SCSI drive, which is just about any newer
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DVD/CD writer.
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Currently only writing to CD-RW, DVD-RW, DVD+RW and DVDRAM discs
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is possible.
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DVD-RW disks must be in restricted overwrite mode.
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See the file <file:Documentation/cdrom/packet-writing.rst>
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for further information on the use of this driver.
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To compile this driver as a module, choose M here: the
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module will be called pktcdvd.
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config CDROM_PKTCDVD_BUFFERS
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int "Free buffers for data gathering"
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depends on CDROM_PKTCDVD
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default "8"
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help
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This controls the maximum number of active concurrent packets. More
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concurrent packets can increase write performance, but also require
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more memory. Each concurrent packet will require approximately 64Kb
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of non-swappable kernel memory, memory which will be allocated when
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a disc is opened for writing.
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config CDROM_PKTCDVD_WCACHE
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bool "Enable write caching"
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depends on CDROM_PKTCDVD
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help
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If enabled, write caching will be set for the CD-R/W device. For now
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this option is dangerous unless the CD-RW media is known good, as we
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don't do deferred write error handling yet.
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config ATA_OVER_ETH
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tristate "ATA over Ethernet support"
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depends on NET
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help
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This driver provides Support for ATA over Ethernet block
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devices like the Coraid EtherDrive (R) Storage Blade.
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config SUNVDC
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tristate "Sun Virtual Disk Client support"
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depends on SUN_LDOMS
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help
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Support for virtual disk devices as a client under Sun
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Logical Domains.
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source "drivers/s390/block/Kconfig"
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config XILINX_SYSACE
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tristate "Xilinx SystemACE support"
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depends on 4xx || MICROBLAZE
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help
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Include support for the Xilinx SystemACE CompactFlash interface
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config XEN_BLKDEV_FRONTEND
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tristate "Xen virtual block device support"
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depends on XEN
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default y
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select XEN_XENBUS_FRONTEND
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help
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This driver implements the front-end of the Xen virtual
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block device driver. It communicates with a back-end driver
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in another domain which drives the actual block device.
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config XEN_BLKDEV_BACKEND
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tristate "Xen block-device backend driver"
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depends on XEN_BACKEND
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help
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The block-device backend driver allows the kernel to export its
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block devices to other guests via a high-performance shared-memory
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interface.
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The corresponding Linux frontend driver is enabled by the
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CONFIG_XEN_BLKDEV_FRONTEND configuration option.
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The backend driver attaches itself to a any block device specified
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in the XenBus configuration. There are no limits to what the block
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device as long as it has a major and minor.
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If you are compiling a kernel to run in a Xen block backend driver
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domain (often this is domain 0) you should say Y here. To
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compile this driver as a module, chose M here: the module
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will be called xen-blkback.
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config VIRTIO_BLK
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tristate "Virtio block driver"
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depends on VIRTIO
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---help---
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This is the virtual block driver for virtio. It can be used with
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QEMU based VMMs (like KVM or Xen). Say Y or M.
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config VIRTIO_BLK_SCSI
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bool "SCSI passthrough request for the Virtio block driver"
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depends on VIRTIO_BLK
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select BLK_SCSI_REQUEST
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---help---
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Enable support for SCSI passthrough (e.g. the SG_IO ioctl) on
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virtio-blk devices. This is only supported for the legacy
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virtio protocol and not enabled by default by any hypervisor.
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You probably want to use virtio-scsi instead.
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config BLK_DEV_RBD
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tristate "Rados block device (RBD)"
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depends on INET && BLOCK
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select CEPH_LIB
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select LIBCRC32C
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select CRYPTO_AES
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select CRYPTO
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help
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Say Y here if you want include the Rados block device, which stripes
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a block device over objects stored in the Ceph distributed object
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store.
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More information at http://ceph.newdream.net/.
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If unsure, say N.
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config BLK_DEV_RSXX
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tristate "IBM Flash Adapter 900GB Full Height PCIe Device Driver"
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depends on PCI
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help
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Device driver for IBM's high speed PCIe SSD
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storage device: Flash Adapter 900GB Full Height.
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To compile this driver as a module, choose M here: the
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module will be called rsxx.
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endif # BLK_DEV
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