[PATCH] BLOCK: Make it possible to disable the block layer [try #6]

[mirror_ubuntu-bionic-kernel.git] / drivers / block / Kconfig

#
# Block device driver configuration
#

if BLOCK

menu "Block devices"

config BLK_DEV_FD
	tristate "Normal floppy disk support"
	depends on ARCH_MAY_HAVE_PC_FDC
	---help---
	  If you want to use the floppy disk drive(s) of your PC under Linux,
	  say Y. Information about this driver, especially important for IBM
	  Thinkpad users, is contained in <file:Documentation/floppy.txt>.
	  That file also contains the location of the Floppy driver FAQ as
	  well as location of the fdutils package used to configure additional
	  parameters of the driver at run time.

	  To compile this driver as a module, choose M here: the
	  module will be called floppy.

config AMIGA_FLOPPY
	tristate "Amiga floppy support"
	depends on AMIGA

config ATARI_FLOPPY
	tristate "Atari floppy support"
	depends on ATARI

config BLK_DEV_SWIM_IOP
	bool "Macintosh IIfx/Quadra 900/Quadra 950 floppy support (EXPERIMENTAL)"
	depends on MAC && EXPERIMENTAL && BROKEN
	help
	  Say Y here to support the SWIM (Super Woz Integrated Machine) IOP
	  floppy controller on the Macintosh IIfx and Quadra 900/950.

config MAC_FLOPPY
	tristate "Support for PowerMac floppy"
	depends on PPC_PMAC && !PPC_PMAC64
	help
	  If you have a SWIM-3 (Super Woz Integrated Machine 3; from Apple)
	  floppy controller, say Y here. Most commonly found in PowerMacs.

config BLK_DEV_PS2
	tristate "PS/2 ESDI hard disk support"
	depends on MCA && MCA_LEGACY && BROKEN
	help
	  Say Y here if you have a PS/2 machine with a MCA bus and an ESDI
	  hard disk.

	  To compile this driver as a module, choose M here: the
	  module will be called ps2esdi.

config AMIGA_Z2RAM
	tristate "Amiga Zorro II ramdisk support"
	depends on ZORRO
	help
	  This enables support for using Chip RAM and Zorro II RAM as a
	  ramdisk or as a swap partition. Say Y if you want to include this
	  driver in the kernel.

	  To compile this driver as a module, choose M here: the
	  module will be called z2ram.

config ATARI_ACSI
	tristate "Atari ACSI support"
	depends on ATARI && BROKEN
	---help---
	  This enables support for the Atari ACSI interface. The driver
	  supports hard disks and CD-ROMs, which have 512-byte sectors, or can
	  be switched to that mode. Due to the ACSI command format, only disks
	  up to 1 GB are supported. Special support for certain ACSI to SCSI
	  adapters, which could relax that, isn't included yet. The ACSI
	  driver is also the basis for certain other drivers for devices
	  attached to the ACSI bus: Atari SLM laser printer, BioNet-100
	  Ethernet, and PAMsNet Ethernet. If you want to use one of these
	  devices, you need ACSI support, too.

	  To compile this driver as a module, choose M here: the
	  module will be called acsi.

comment "Some devices (e.g. CD jukebox) support multiple LUNs"
	depends on ATARI && ATARI_ACSI

config ACSI_MULTI_LUN
	bool "Probe all LUNs on each ACSI device"
	depends on ATARI_ACSI
	help
	  If you have a ACSI device that supports more than one LUN (Logical
	  Unit Number), e.g. a CD jukebox, you should say Y here so that all
	  will be found by the ACSI driver. An ACSI device with multiple LUNs
	  acts logically like multiple ACSI devices. The vast majority of ACSI
	  devices have only one LUN, and so most people can say N here and
	  should in fact do so, because it is safer.

config ATARI_SLM
	tristate "Atari SLM laser printer support"
	depends on ATARI && ATARI_ACSI!=n
	help
	  If you have an Atari SLM laser printer, say Y to include support for
	  it in the kernel. Otherwise, say N. This driver is also available as
	  a module ( = code which can be inserted in and removed from the
	  running kernel whenever you want). The module will be called
	  acsi_slm. Be warned: the driver needs much ST-RAM and can cause
	  problems due to that fact!

config BLK_DEV_XD
	tristate "XT hard disk support"
	depends on ISA && ISA_DMA_API
	help
	  Very old 8 bit hard disk controllers used in the IBM XT computer
	  will be supported if you say Y here.

	  To compile this driver as a module, choose M here: the
	  module will be called xd.

	  It's pretty unlikely that you have one of these: say N.

config PARIDE
	tristate "Parallel port IDE device support"
	depends on PARPORT_PC
	---help---
	  There are many external CD-ROM and disk devices that connect through
	  your computer's parallel port. Most of them are actually IDE devices
	  using a parallel port IDE adapter. This option enables the PARIDE
	  subsystem which contains drivers for many of these external drives.
	  Read <file:Documentation/paride.txt> for more information.

	  If you have said Y to the "Parallel-port support" configuration
	  option, you may share a single port between your printer and other
	  parallel port devices. Answer Y to build PARIDE support into your
	  kernel, or M if you would like to build it as a loadable module. If
	  your parallel port support is in a loadable module, you must build
	  PARIDE as a module. If you built PARIDE support into your kernel,
	  you may still build the individual protocol modules and high-level
	  drivers as loadable modules. If you build this support as a module,
	  it will be called paride.

	  To use the PARIDE support, you must say Y or M here and also to at
	  least one high-level driver (e.g. "Parallel port IDE disks",
	  "Parallel port ATAPI CD-ROMs", "Parallel port ATAPI disks" etc.) and
	  to at least one protocol driver (e.g. "ATEN EH-100 protocol",
	  "MicroSolutions backpack protocol", "DataStor Commuter protocol"
	  etc.).

source "drivers/block/paride/Kconfig"

config BLK_CPQ_DA
	tristate "Compaq SMART2 support"
	depends on PCI
	help
	  This is the driver for Compaq Smart Array controllers.  Everyone
	  using these boards should say Y here.  See the file
	  <file:Documentation/cpqarray.txt> for the current list of boards
	  supported by this driver, and for further information on the use of
	  this driver.

config BLK_CPQ_CISS_DA
	tristate "Compaq Smart Array 5xxx support"
	depends on PCI
	help
	  This is the driver for Compaq Smart Array 5xxx controllers.
	  Everyone using these boards should say Y here.
	  See <file:Documentation/cciss.txt> for the current list of
	  boards supported by this driver, and for further information
	  on the use of this driver.

config CISS_SCSI_TAPE
	bool "SCSI tape drive support for Smart Array 5xxx"
	depends on BLK_CPQ_CISS_DA && SCSI && PROC_FS
	help
	  When enabled (Y), this option allows SCSI tape drives and SCSI medium
	  changers (tape robots) to be accessed via a Compaq 5xxx array 
	  controller.  (See <file:Documentation/cciss.txt> for more details.)

	  "SCSI support" and "SCSI tape support" must also be enabled for this 
	  option to work.

	  When this option is disabled (N), the SCSI portion of the driver 
	  is not compiled.

config BLK_DEV_DAC960
	tristate "Mylex DAC960/DAC1100 PCI RAID Controller support"
	depends on PCI
	help
	  This driver adds support for the Mylex DAC960, AcceleRAID, and
	  eXtremeRAID PCI RAID controllers.  See the file
	  <file:Documentation/README.DAC960> for further information about
	  this driver.

	  To compile this driver as a module, choose M here: the
	  module will be called DAC960.

config BLK_DEV_UMEM
	tristate "Micro Memory MM5415 Battery Backed RAM support (EXPERIMENTAL)"
	depends on PCI && EXPERIMENTAL
	---help---
	  Saying Y here will include support for the MM5415 family of
	  battery backed (Non-volatile) RAM cards.
	  <http://www.umem.com/>

	  The cards appear as block devices that can be partitioned into
	  as many as 15 partitions.

	  To compile this driver as a module, choose M here: the
	  module will be called umem.

	  The umem driver has not yet been allocated a MAJOR number, so
	  one is chosen dynamically.  Use "devfs" or look in /proc/devices
	  for the device number

config BLK_DEV_UBD
	bool "Virtual block device"
	depends on UML
	---help---
          The User-Mode Linux port includes a driver called UBD which will let
          you access arbitrary files on the host computer as block devices.
          Unless you know that you do not need such virtual block devices say
          Y here.

config BLK_DEV_UBD_SYNC
	bool "Always do synchronous disk IO for UBD"
	depends on BLK_DEV_UBD
	---help---
	  Writes to the virtual block device are not immediately written to the
	  host's disk; this may cause problems if, for example, the User-Mode
	  Linux 'Virtual Machine' uses a journalling filesystem and the host
	  computer crashes.

          Synchronous operation (i.e. always writing data to the host's disk
          immediately) is configurable on a per-UBD basis by using a special
          kernel command line option.  Alternatively, you can say Y here to
          turn on synchronous operation by default for all block devices.

          If you're running a journalling file system (like reiserfs, for
          example) in your virtual machine, you will want to say Y here.  If
          you care for the safety of the data in your virtual machine, Y is a
          wise choice too.  In all other cases (for example, if you're just
          playing around with User-Mode Linux) you can choose N.

config BLK_DEV_COW_COMMON
	bool
	default BLK_DEV_UBD

config MMAPPER
	tristate "Example IO memory driver (BROKEN)"
	depends on UML && BROKEN
	---help---
          The User-Mode Linux port can provide support for IO Memory
          emulation with this option.  This allows a host file to be
          specified as an I/O region on the kernel command line. That file
          will be mapped into UML's kernel address space where a driver can
          locate it and do whatever it wants with the memory, including
          providing an interface to it for UML processes to use.

          For more information, see
          <http://user-mode-linux.sourceforge.net/iomem.html>.

          If you'd like to be able to provide a simulated IO port space for
          User-Mode Linux processes, say Y.  If unsure, say N.

config BLK_DEV_LOOP
	tristate "Loopback device support"
	---help---
	  Saying Y here will allow you to use a regular file as a block
	  device; you can then create a file system on that block device and
	  mount it just as you would mount other block devices such as hard
	  drive partitions, CD-ROM drives or floppy drives. The loop devices
	  are block special device files with major number 7 and typically
	  called /dev/loop0, /dev/loop1 etc.

	  This is useful if you want to check an ISO 9660 file system before
	  burning the CD, or if you want to use floppy images without first
	  writing them to floppy. Furthermore, some Linux distributions avoid
	  the need for a dedicated Linux partition by keeping their complete
	  root file system inside a DOS FAT file using this loop device
	  driver.

	  To use the loop device, you need the losetup utility, found in the
	  util-linux package, see
	  <ftp://ftp.kernel.org/pub/linux/utils/util-linux/>.

	  The loop device driver can also be used to "hide" a file system in
	  a disk partition, floppy, or regular file, either using encryption
	  (scrambling the data) or steganography (hiding the data in the low
	  bits of, say, a sound file). This is also safe if the file resides
	  on a remote file server.

	  There are several ways of encrypting disks. Some of these require
	  kernel patches. The vanilla kernel offers the cryptoloop option
	  and a Device Mapper target (which is superior, as it supports all
	  file systems). If you want to use the cryptoloop, say Y to both
	  LOOP and CRYPTOLOOP, and make sure you have a recent (version 2.12
	  or later) version of util-linux. Additionally, be aware that
	  the cryptoloop is not safe for storing journaled filesystems.

	  Note that this loop device has nothing to do with the loopback
	  device used for network connections from the machine to itself.

	  To compile this driver as a module, choose M here: the
	  module will be called loop.

	  Most users will answer N here.

config BLK_DEV_CRYPTOLOOP
	tristate "Cryptoloop Support"
	select CRYPTO
	depends on BLK_DEV_LOOP
	---help---
	  Say Y here if you want to be able to use the ciphers that are 
	  provided by the CryptoAPI as loop transformation. This might be
	  used as hard disk encryption.

	  WARNING: This device is not safe for journaled file systems like
	  ext3 or Reiserfs. Please use the Device Mapper crypto module
	  instead, which can be configured to be on-disk compatible with the
	  cryptoloop device.

config BLK_DEV_NBD
	tristate "Network block device support"
	depends on NET
	---help---
	  Saying Y here will allow your computer to be a client for network
	  block devices, i.e. it will be able to use block devices exported by
	  servers (mount file systems on them etc.). Communication between
	  client and server works over TCP/IP networking, but to the client
	  program this is hidden: it looks like a regular local file access to
	  a block device special file such as /dev/nd0.

	  Network block devices also allows you to run a block-device in
	  userland (making server and client physically the same computer,
	  communicating using the loopback network device).

	  Read <file:Documentation/nbd.txt> for more information, especially
	  about where to find the server code, which runs in user space and
	  does not need special kernel support.

	  Note that this has nothing to do with the network file systems NFS
	  or Coda; you can say N here even if you intend to use NFS or Coda.

	  To compile this driver as a module, choose M here: the
	  module will be called nbd.

	  If unsure, say N.

config BLK_DEV_SX8
	tristate "Promise SATA SX8 support"
	depends on PCI
	---help---
	  Saying Y or M here will enable support for the 
	  Promise SATA SX8 controllers.

	  Use devices /dev/sx8/$N and /dev/sx8/$Np$M.

config BLK_DEV_UB
	tristate "Low Performance USB Block driver"
	depends on USB
	help
	  This driver supports certain USB attached storage devices
	  such as flash keys.

	  If you enable this driver, it is recommended to avoid conflicts
	  with usb-storage by enabling USB_LIBUSUAL.

	  If unsure, say N.

config BLK_DEV_RAM
	tristate "RAM disk support"
	---help---
	  Saying Y here will allow you to use a portion of your RAM memory as
	  a block device, so that you can make file systems on it, read and
	  write to it and do all the other things that you can do with normal
	  block devices (such as hard drives). It is usually used to load and
	  store a copy of a minimal root file system off of a floppy into RAM
	  during the initial install of Linux.

	  Note that the kernel command line option "ramdisk=XX" is now
	  obsolete. For details, read <file:Documentation/ramdisk.txt>.

	  To compile this driver as a module, choose M here: the
	  module will be called rd.

	  Most normal users won't need the RAM disk functionality, and can
	  thus say N here.

config BLK_DEV_RAM_COUNT
	int "Default number of RAM disks"
	default "16"
	depends on BLK_DEV_RAM
	help
	  The default value is 16 RAM disks. Change this if you know what
	  are doing. If you boot from a filesystem that needs to be extracted
	  in memory, you will need at least one RAM disk (e.g. root on cramfs).

config BLK_DEV_RAM_SIZE
	int "Default RAM disk size (kbytes)"
	depends on BLK_DEV_RAM
	default "4096"
	help
	  The default value is 4096 kilobytes. Only change this if you know
	  what are you doing. If you are using IBM S/390, then set this to
	  8192.

config BLK_DEV_RAM_BLOCKSIZE
	int "Default RAM disk block size (bytes)"
	depends on BLK_DEV_RAM
	default "1024"
	help
	  The default value is 1024 kilobytes.  PAGE_SIZE is a much more
	  efficient choice however.  The default is kept to ensure initrd
	  setups function - apparently needed by the rd_load_image routine
	  that supposes the filesystem in the image uses a 1024 blocksize.

config BLK_DEV_INITRD
	bool "Initial RAM filesystem and RAM disk (initramfs/initrd) support"
	depends on BROKEN || !FRV
	help
	  The initial RAM filesystem is a ramfs which is loaded by the
	  boot loader (loadlin or lilo) and that is mounted as root
	  before the normal boot procedure. It is typically used to
	  load modules needed to mount the "real" root file system,
	  etc. See <file:Documentation/initrd.txt> for details.

	  If RAM disk support (BLK_DEV_RAM) is also included, this
	  also enables initial RAM disk (initrd) support.


config CDROM_PKTCDVD
	tristate "Packet writing on CD/DVD media"
	depends on !UML
	help
	  If you have a CDROM drive that supports packet writing, say Y to
	  include preliminary support. It should work with any MMC/Mt Fuji
	  compliant ATAPI or SCSI drive, which is just about any newer CD
	  writer.

	  Currently only writing to CD-RW, DVD-RW and DVD+RW discs is possible.
	  DVD-RW disks must be in restricted overwrite mode.

	  To compile this driver as a module, choose M here: the
	  module will be called pktcdvd.

config CDROM_PKTCDVD_BUFFERS
	int "Free buffers for data gathering"
	depends on CDROM_PKTCDVD
	default "8"
	help
	  This controls the maximum number of active concurrent packets. More
	  concurrent packets can increase write performance, but also require
	  more memory. Each concurrent packet will require approximately 64Kb
	  of non-swappable kernel memory, memory which will be allocated when
	  a disc is opened for writing.

config CDROM_PKTCDVD_WCACHE
	bool "Enable write caching (EXPERIMENTAL)"
	depends on CDROM_PKTCDVD && EXPERIMENTAL
	help
	  If enabled, write caching will be set for the CD-R/W device. For now
	  this option is dangerous unless the CD-RW media is known good, as we
	  don't do deferred write error handling yet.

source "drivers/s390/block/Kconfig"

config ATA_OVER_ETH
	tristate "ATA over Ethernet support"
	depends on NET
	help
	This driver provides Support for ATA over Ethernet block
	devices like the Coraid EtherDrive (R) Storage Blade.

endmenu

endif