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

# SPDX-License-Identifier: GPL-2.0
#
# Block device driver configuration
#

menuconfig BLK_DEV
	bool "Block devices"
	depends on BLOCK
	default y
	---help---
	  Say Y here to get to see options for various different block device
	  drivers. This option alone does not add any kernel code.

	  If you say N, all options in this submenu will be skipped and disabled;
	  only do this if you know what you are doing.

if BLK_DEV

config BLK_DEV_NULL_BLK
	tristate "Null test block driver"
	select CONFIGFS_FS

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/blockdev/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 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_SWIM
	tristate "Support for SWIM Macintosh floppy"
	depends on M68K && MAC
	help
	  You should select this option if you want floppy support
	  and you don't have a II, IIfx, Q900, Q950 or AV series.

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 CDROM
	tristate

config GDROM
	tristate "SEGA Dreamcast GD-ROM drive"
	depends on SH_DREAMCAST
	select CDROM
	select BLK_SCSI_REQUEST # only for the generic cdrom code
	help
	  A standard SEGA Dreamcast comes with a modified CD ROM drive called a
	  "GD-ROM" by SEGA to signify it is capable of reading special disks
	  with up to 1 GB of data. This drive will also read standard CD ROM
	  disks. Select this option to access any disks in your GD ROM drive.
	  Most users will want to say "Y" here.
	  You can also build this as a module which will be called gdrom.

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/blockdev/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"

source "drivers/block/mtip32xx/Kconfig"

source "drivers/block/zram/Kconfig"

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/blockdev/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"
	depends on PCI
	---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.

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 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
	  <https://www.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_LOOP_MIN_COUNT
	int "Number of loop devices to pre-create at init time"
	depends on BLK_DEV_LOOP
	default 8
	help
	  Static number of loop devices to be unconditionally pre-created
	  at init time.

	  This default value can be overwritten on the kernel command
	  line or with module-parameter loop.max_loop.

	  The historic default is 8. If a late 2011 version of losetup(8)
	  is used, it can be set to 0, since needed loop devices can be
	  dynamically allocated with the /dev/loop-control interface.

config BLK_DEV_CRYPTOLOOP
	tristate "Cryptoloop Support"
	select CRYPTO
	select CRYPTO_CBC
	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.

source "drivers/block/drbd/Kconfig"

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/blockdev/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_SKD
	tristate "STEC S1120 Block Driver"
	depends on PCI
	depends on 64BIT
	---help---
	Saying Y or M here will enable support for the
	STEC, Inc. S1120 PCIe SSD.

	Use device /dev/skd$N amd /dev/skd$Np$M.

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_RAM
	tristate "RAM block device 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/blockdev/ramdisk.txt>.

	  To compile this driver as a module, choose M here: the
	  module will be called brd. An alias "rd" has been defined
	  for historical reasons.

	  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 you
	  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 you are doing.

config CDROM_PKTCDVD
	tristate "Packet writing on CD/DVD media (DEPRECATED)"
	depends on !UML
	select CDROM
	select BLK_SCSI_REQUEST
	help
	  Note: This driver is deprecated and will be removed from the
	  kernel in the near future!

	  If you have a CDROM/DVD drive that supports packet writing, say
	  Y to include support. It should work with any MMC/Mt Fuji
	  compliant ATAPI or SCSI drive, which is just about any newer
	  DVD/CD writer.

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

	  See the file <file:Documentation/cdrom/packet-writing.txt>
	  for further information on the use of this driver.

	  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"
	depends on CDROM_PKTCDVD
	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.

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.

config SUNVDC
	tristate "Sun Virtual Disk Client support"
	depends on SUN_LDOMS
	help
	  Support for virtual disk devices as a client under Sun
	  Logical Domains.

source "drivers/s390/block/Kconfig"

config XILINX_SYSACE
	tristate "Xilinx SystemACE support"
	depends on 4xx || MICROBLAZE
	help
	  Include support for the Xilinx SystemACE CompactFlash interface

config XEN_BLKDEV_FRONTEND
	tristate "Xen virtual block device support"
	depends on XEN
	default y
	select XEN_XENBUS_FRONTEND
	help
	  This driver implements the front-end of the Xen virtual
	  block device driver.  It communicates with a back-end driver
	  in another domain which drives the actual block device.

config XEN_BLKDEV_BACKEND
	tristate "Xen block-device backend driver"
	depends on XEN_BACKEND
	help
	  The block-device backend driver allows the kernel to export its
	  block devices to other guests via a high-performance shared-memory
	  interface.

	  The corresponding Linux frontend driver is enabled by the
	  CONFIG_XEN_BLKDEV_FRONTEND configuration option.

	  The backend driver attaches itself to a any block device specified
	  in the XenBus configuration. There are no limits to what the block
	  device as long as it has a major and minor.

	  If you are compiling a kernel to run in a Xen block backend driver
	  domain (often this is domain 0) you should say Y here. To
	  compile this driver as a module, chose M here: the module
	  will be called xen-blkback.


config VIRTIO_BLK
	tristate "Virtio block driver"
	depends on VIRTIO
	---help---
	  This is the virtual block driver for virtio.  It can be used with
          QEMU based VMMs (like KVM or Xen).  Say Y or M.

config VIRTIO_BLK_SCSI
	bool "SCSI passthrough request for the Virtio block driver"
	depends on VIRTIO_BLK
	select BLK_SCSI_REQUEST
	---help---
	  Enable support for SCSI passthrough (e.g. the SG_IO ioctl) on
	  virtio-blk devices.  This is only supported for the legacy
	  virtio protocol and not enabled by default by any hypervisor.
	  You probably want to use virtio-scsi instead.

config BLK_DEV_RBD
	tristate "Rados block device (RBD)"
	depends on INET && BLOCK
	select CEPH_LIB
	select LIBCRC32C
	select CRYPTO_AES
	select CRYPTO
	default n
	help
	  Say Y here if you want include the Rados block device, which stripes
	  a block device over objects stored in the Ceph distributed object
	  store.

	  More information at http://ceph.newdream.net/.

	  If unsure, say N.

config BLK_DEV_RSXX
	tristate "IBM Flash Adapter 900GB Full Height PCIe Device Driver"
	depends on PCI
	help
	  Device driver for IBM's high speed PCIe SSD
	  storage device: Flash Adapter 900GB Full Height.

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

endif # BLK_DEV
Commit	Line	Data
b2441318	1	# SPDX-License-Identifier: GPL-2.0
1da177e4 LT	2	#
	3	# Block device driver configuration
	4	#
	5
fd11d171 JE	6	menuconfig BLK_DEV
	7	bool "Block devices"
	8	depends on BLOCK
	9	default y
06bfb7eb JE	10	---help---
	11	Say Y here to get to see options for various different block device
	12	drivers. This option alone does not add any kernel code.
	13
	14	If you say N, all options in this submenu will be skipped and disabled;
	15	only do this if you know what you are doing.
9361401e	16
fd11d171	17	if BLK_DEV
1da177e4	18
f2298c04 JA	19	config BLK_DEV_NULL_BLK
f2298c04 JA	20	tristate "Null test block driver"
6cd1a6fe	21	select CONFIGFS_FS
f2298c04	22
1da177e4 LT	23	config BLK_DEV_FD
1da177e4 LT	24	tristate "Normal floppy disk support"
a08b6b79	25	depends on ARCH_MAY_HAVE_PC_FDC
1da177e4 LT	26	---help---
	27	If you want to use the floppy disk drive(s) of your PC under Linux,
	28	say Y. Information about this driver, especially important for IBM
31c00fc1 RD	29	Thinkpad users, is contained in
31c00fc1 RD	30	<file:Documentation/blockdev/floppy.txt>.
1da177e4 LT	31	That file also contains the location of the Floppy driver FAQ as
	32	well as location of the fdutils package used to configure additional
	33	parameters of the driver at run time.
	34
	35	To compile this driver as a module, choose M here: the
	36	module will be called floppy.
	37
	38	config AMIGA_FLOPPY
	39	tristate "Amiga floppy support"
	40	depends on AMIGA
	41
	42	config ATARI_FLOPPY
	43	tristate "Atari floppy support"
	44	depends on ATARI
	45
1da177e4 LT	46	config MAC_FLOPPY
	47	tristate "Support for PowerMac floppy"
	48	depends on PPC_PMAC && !PPC_PMAC64
	49	help
	50	If you have a SWIM-3 (Super Woz Integrated Machine 3; from Apple)
	51	floppy controller, say Y here. Most commonly found in PowerMacs.
	52
8852ecd9 LV	53	config BLK_DEV_SWIM
	54	tristate "Support for SWIM Macintosh floppy"
	55	depends on M68K && MAC
	56	help
	57	You should select this option if you want floppy support
	58	and you don't have a II, IIfx, Q900, Q950 or AV series.
	59
1da177e4 LT	60	config AMIGA_Z2RAM
	61	tristate "Amiga Zorro II ramdisk support"
	62	depends on ZORRO
	63	help
	64	This enables support for using Chip RAM and Zorro II RAM as a
	65	ramdisk or as a swap partition. Say Y if you want to include this
	66	driver in the kernel.
	67
	68	To compile this driver as a module, choose M here: the
	69	module will be called z2ram.
	70
2a750166	71	config CDROM
a116895f	72	tristate
2a750166	73
2395e463 RD	74	config GDROM
	75	tristate "SEGA Dreamcast GD-ROM drive"
	76	depends on SH_DREAMCAST
2a750166	77	select CDROM
72148aec	78	select BLK_SCSI_REQUEST # only for the generic cdrom code
2395e463 RD	79	help
	80	A standard SEGA Dreamcast comes with a modified CD ROM drive called a
	81	"GD-ROM" by SEGA to signify it is capable of reading special disks
	82	with up to 1 GB of data. This drive will also read standard CD ROM
	83	disks. Select this option to access any disks in your GD ROM drive.
	84	Most users will want to say "Y" here.
	85	You can also build this as a module which will be called gdrom.
	86
1da177e4 LT	87	config PARIDE
1da177e4 LT	88	tristate "Parallel port IDE device support"
6a19b41b	89	depends on PARPORT_PC
1da177e4 LT	90	---help---
	91	There are many external CD-ROM and disk devices that connect through
	92	your computer's parallel port. Most of them are actually IDE devices
	93	using a parallel port IDE adapter. This option enables the PARIDE
	94	subsystem which contains drivers for many of these external drives.
31c00fc1	95	Read <file:Documentation/blockdev/paride.txt> for more information.
1da177e4 LT	96
	97	If you have said Y to the "Parallel-port support" configuration
	98	option, you may share a single port between your printer and other
	99	parallel port devices. Answer Y to build PARIDE support into your
	100	kernel, or M if you would like to build it as a loadable module. If
	101	your parallel port support is in a loadable module, you must build
	102	PARIDE as a module. If you built PARIDE support into your kernel,
	103	you may still build the individual protocol modules and high-level
	104	drivers as loadable modules. If you build this support as a module,
	105	it will be called paride.
	106
	107	To use the PARIDE support, you must say Y or M here and also to at
	108	least one high-level driver (e.g. "Parallel port IDE disks",
	109	"Parallel port ATAPI CD-ROMs", "Parallel port ATAPI disks" etc.) and
	110	to at least one protocol driver (e.g. "ATEN EH-100 protocol",
	111	"MicroSolutions backpack protocol", "DataStor Commuter protocol"
	112	etc.).
	113
	114	source "drivers/block/paride/Kconfig"
	115
88523a61 SB	116	source "drivers/block/mtip32xx/Kconfig"
88523a61 SB	117
cd67e10a MK	118	source "drivers/block/zram/Kconfig"
cd67e10a MK	119
1da177e4 LT	120	config BLK_DEV_DAC960
	121	tristate "Mylex DAC960/DAC1100 PCI RAID Controller support"
	122	depends on PCI
	123	help
	124	This driver adds support for the Mylex DAC960, AcceleRAID, and
	125	eXtremeRAID PCI RAID controllers. See the file
31c00fc1 RD	126	<file:Documentation/blockdev/README.DAC960> for further information
31c00fc1 RD	127	about this driver.
1da177e4 LT	128
	129	To compile this driver as a module, choose M here: the
	130	module will be called DAC960.
	131
	132	config BLK_DEV_UMEM
b8977285 KC	133	tristate "Micro Memory MM5415 Battery Backed RAM support"
b8977285 KC	134	depends on PCI
1da177e4 LT	135	---help---
	136	Saying Y here will include support for the MM5415 family of
	137	battery backed (Non-volatile) RAM cards.
	138	<http://www.umem.com/>
	139
	140	The cards appear as block devices that can be partitioned into
	141	as many as 15 partitions.
	142
	143	To compile this driver as a module, choose M here: the
	144	module will be called umem.
	145
	146	The umem driver has not yet been allocated a MAJOR number, so
bf6ee0ae	147	one is chosen dynamically.
1da177e4 LT	148
	149	config BLK_DEV_UBD
	150	bool "Virtual block device"
	151	depends on UML
	152	---help---
	153	The User-Mode Linux port includes a driver called UBD which will let
	154	you access arbitrary files on the host computer as block devices.
	155	Unless you know that you do not need such virtual block devices say
	156	Y here.
	157
	158	config BLK_DEV_UBD_SYNC
	159	bool "Always do synchronous disk IO for UBD"
	160	depends on BLK_DEV_UBD
	161	---help---
	162	Writes to the virtual block device are not immediately written to the
	163	host's disk; this may cause problems if, for example, the User-Mode
	164	Linux 'Virtual Machine' uses a journalling filesystem and the host
	165	computer crashes.
	166
	167	Synchronous operation (i.e. always writing data to the host's disk
	168	immediately) is configurable on a per-UBD basis by using a special
	169	kernel command line option. Alternatively, you can say Y here to
	170	turn on synchronous operation by default for all block devices.
	171
	172	If you're running a journalling file system (like reiserfs, for
	173	example) in your virtual machine, you will want to say Y here. If
	174	you care for the safety of the data in your virtual machine, Y is a
	175	wise choice too. In all other cases (for example, if you're just
	176	playing around with User-Mode Linux) you can choose N.
	177
	178	config BLK_DEV_COW_COMMON
	179	bool
	180	default BLK_DEV_UBD
	181
1da177e4 LT	182	config BLK_DEV_LOOP
	183	tristate "Loopback device support"
	184	---help---
	185	Saying Y here will allow you to use a regular file as a block
	186	device; you can then create a file system on that block device and
	187	mount it just as you would mount other block devices such as hard
	188	drive partitions, CD-ROM drives or floppy drives. The loop devices
	189	are block special device files with major number 7 and typically
	190	called /dev/loop0, /dev/loop1 etc.
	191
	192	This is useful if you want to check an ISO 9660 file system before
	193	burning the CD, or if you want to use floppy images without first
	194	writing them to floppy. Furthermore, some Linux distributions avoid
	195	the need for a dedicated Linux partition by keeping their complete
	196	root file system inside a DOS FAT file using this loop device
	197	driver.
	198
	199	To use the loop device, you need the losetup utility, found in the
	200	util-linux package, see
4f6cce39	201	<https://www.kernel.org/pub/linux/utils/util-linux/>.
1da177e4 LT	202
	203	The loop device driver can also be used to "hide" a file system in
	204	a disk partition, floppy, or regular file, either using encryption
	205	(scrambling the data) or steganography (hiding the data in the low
	206	bits of, say, a sound file). This is also safe if the file resides
	207	on a remote file server.
	208
	209	There are several ways of encrypting disks. Some of these require
	210	kernel patches. The vanilla kernel offers the cryptoloop option
	211	and a Device Mapper target (which is superior, as it supports all
	212	file systems). If you want to use the cryptoloop, say Y to both
	213	LOOP and CRYPTOLOOP, and make sure you have a recent (version 2.12
	214	or later) version of util-linux. Additionally, be aware that
	215	the cryptoloop is not safe for storing journaled filesystems.
	216
	217	Note that this loop device has nothing to do with the loopback
	218	device used for network connections from the machine to itself.
	219
	220	To compile this driver as a module, choose M here: the
	221	module will be called loop.
	222
	223	Most users will answer N here.
	224
d134b00b KS	225	config BLK_DEV_LOOP_MIN_COUNT
	226	int "Number of loop devices to pre-create at init time"
	227	depends on BLK_DEV_LOOP
	228	default 8
	229	help
	230	Static number of loop devices to be unconditionally pre-created
	231	at init time.
	232
	233	This default value can be overwritten on the kernel command
	234	line or with module-parameter loop.max_loop.
	235
	236	The historic default is 8. If a late 2011 version of losetup(8)
	237	is used, it can be set to 0, since needed loop devices can be
	238	dynamically allocated with the /dev/loop-control interface.
	239
1da177e4 LT	240	config BLK_DEV_CRYPTOLOOP
	241	tristate "Cryptoloop Support"
	242	select CRYPTO
8df3b0a2	243	select CRYPTO_CBC
1da177e4 LT	244	depends on BLK_DEV_LOOP
	245	---help---
	246	Say Y here if you want to be able to use the ciphers that are
	247	provided by the CryptoAPI as loop transformation. This might be
	248	used as hard disk encryption.
	249
	250	WARNING: This device is not safe for journaled file systems like
	251	ext3 or Reiserfs. Please use the Device Mapper crypto module
	252	instead, which can be configured to be on-disk compatible with the
	253	cryptoloop device.
	254
b411b363 PR	255	source "drivers/block/drbd/Kconfig"
b411b363 PR	256
1da177e4 LT	257	config BLK_DEV_NBD
	258	tristate "Network block device support"
	259	depends on NET
	260	---help---
	261	Saying Y here will allow your computer to be a client for network
	262	block devices, i.e. it will be able to use block devices exported by
	263	servers (mount file systems on them etc.). Communication between
	264	client and server works over TCP/IP networking, but to the client
	265	program this is hidden: it looks like a regular local file access to
	266	a block device special file such as /dev/nd0.
	267
	268	Network block devices also allows you to run a block-device in
	269	userland (making server and client physically the same computer,
	270	communicating using the loopback network device).
	271
31c00fc1 RD	272	Read <file:Documentation/blockdev/nbd.txt> for more information,
	273	especially about where to find the server code, which runs in user
	274	space and does not need special kernel support.
1da177e4 LT	275
	276	Note that this has nothing to do with the network file systems NFS
	277	or Coda; you can say N here even if you intend to use NFS or Coda.
	278
	279	To compile this driver as a module, choose M here: the
	280	module will be called nbd.
	281
	282	If unsure, say N.
	283
e67f86b3 AB	284	config BLK_DEV_SKD
	285	tristate "STEC S1120 Block Driver"
	286	depends on PCI
	287	depends on 64BIT
	288	---help---
	289	Saying Y or M here will enable support for the
	290	STEC, Inc. S1120 PCIe SSD.
	291
	292	Use device /dev/skd$N amd /dev/skd$Np$M.
	293
1da177e4 LT	294	config BLK_DEV_SX8
	295	tristate "Promise SATA SX8 support"
	296	depends on PCI
	297	---help---
	298	Saying Y or M here will enable support for the
	299	Promise SATA SX8 controllers.
	300
	301	Use devices /dev/sx8/$N and /dev/sx8/$Np$M.
1da177e4 LT	302
1da177e4 LT	303	config BLK_DEV_RAM
9db5579b	304	tristate "RAM block device support"
1da177e4 LT	305	---help---
	306	Saying Y here will allow you to use a portion of your RAM memory as
	307	a block device, so that you can make file systems on it, read and
	308	write to it and do all the other things that you can do with normal
	309	block devices (such as hard drives). It is usually used to load and
	310	store a copy of a minimal root file system off of a floppy into RAM
	311	during the initial install of Linux.
	312
31c00fc1 RD	313	Note that the kernel command line option "ramdisk=XX" is now obsolete.
31c00fc1 RD	314	For details, read <file:Documentation/blockdev/ramdisk.txt>.
1da177e4 LT	315
1da177e4 LT	316	To compile this driver as a module, choose M here: the
a3b25d9b FF	317	module will be called brd. An alias "rd" has been defined
a3b25d9b FF	318	for historical reasons.
1da177e4 LT	319
	320	Most normal users won't need the RAM disk functionality, and can
	321	thus say N here.
	322
	323	config BLK_DEV_RAM_COUNT
a687fb18	324	int "Default number of RAM disks"
1da177e4	325	default "16"
a687fb18	326	depends on BLK_DEV_RAM
1da177e4	327	help
2e977c85	328	The default value is 16 RAM disks. Change this if you know what you
1da177e4 LT	329	are doing. If you boot from a filesystem that needs to be extracted
	330	in memory, you will need at least one RAM disk (e.g. root on cramfs).
	331
	332	config BLK_DEV_RAM_SIZE
	333	int "Default RAM disk size (kbytes)"
	334	depends on BLK_DEV_RAM
	335	default "4096"
	336	help
	337	The default value is 4096 kilobytes. Only change this if you know
2e977c85	338	what you are doing.
1da177e4	339
1da177e4	340	config CDROM_PKTCDVD
5a8b187c	341	tristate "Packet writing on CD/DVD media (DEPRECATED)"
1da177e4	342	depends on !UML
2a750166	343	select CDROM
72148aec	344	select BLK_SCSI_REQUEST
1da177e4	345	help
5a8b187c JA	346	Note: This driver is deprecated and will be removed from the
	347	kernel in the near future!
	348
2d4eeec5 TM	349	If you have a CDROM/DVD drive that supports packet writing, say
	350	Y to include support. It should work with any MMC/Mt Fuji
	351	compliant ATAPI or SCSI drive, which is just about any newer
	352	DVD/CD writer.
1da177e4	353
2d4eeec5 TM	354	Currently only writing to CD-RW, DVD-RW, DVD+RW and DVDRAM discs
2d4eeec5 TM	355	is possible.
1da177e4 LT	356	DVD-RW disks must be in restricted overwrite mode.
1da177e4 LT	357
2d4eeec5 TM	358	See the file <file:Documentation/cdrom/packet-writing.txt>
	359	for further information on the use of this driver.
	360
1da177e4 LT	361	To compile this driver as a module, choose M here: the
	362	module will be called pktcdvd.
	363
	364	config CDROM_PKTCDVD_BUFFERS
	365	int "Free buffers for data gathering"
	366	depends on CDROM_PKTCDVD
	367	default "8"
	368	help
	369	This controls the maximum number of active concurrent packets. More
	370	concurrent packets can increase write performance, but also require
	371	more memory. Each concurrent packet will require approximately 64Kb
e1bc89bc PO	372	of non-swappable kernel memory, memory which will be allocated when
e1bc89bc PO	373	a disc is opened for writing.
1da177e4 LT	374
1da177e4 LT	375	config CDROM_PKTCDVD_WCACHE
b8977285 KC	376	bool "Enable write caching"
b8977285 KC	377	depends on CDROM_PKTCDVD
1da177e4 LT	378	help
	379	If enabled, write caching will be set for the CD-R/W device. For now
	380	this option is dangerous unless the CD-RW media is known good, as we
	381	don't do deferred write error handling yet.
	382
1da177e4 LT	383	config ATA_OVER_ETH
	384	tristate "ATA over Ethernet support"
	385	depends on NET
	386	help
	387	This driver provides Support for ATA over Ethernet block
	388	devices like the Coraid EtherDrive (R) Storage Blade.
	389
667ef3c3 DM	390	config SUNVDC
	391	tristate "Sun Virtual Disk Client support"
	392	depends on SUN_LDOMS
	393	help
	394	Support for virtual disk devices as a client under Sun
	395	Logical Domains.
	396
61d48c2c MS	397	source "drivers/s390/block/Kconfig"
61d48c2c MS	398
74489a91 GL	399	config XILINX_SYSACE
74489a91 GL	400	tristate "Xilinx SystemACE support"
6fa612b5	401	depends on 4xx \|\| MICROBLAZE
74489a91 GL	402	help
	403	Include support for the Xilinx SystemACE CompactFlash interface
	404
9f27ee59 JF	405	config XEN_BLKDEV_FRONTEND
	406	tristate "Xen virtual block device support"
	407	depends on XEN
	408	default y
2de06cc1	409	select XEN_XENBUS_FRONTEND
9f27ee59 JF	410	help
	411	This driver implements the front-end of the Xen virtual
	412	block device driver. It communicates with a back-end driver
	413	in another domain which drives the actual block device.
	414
dfc07b13	415	config XEN_BLKDEV_BACKEND
ea5e1161	416	tristate "Xen block-device backend driver"
dfc07b13 KRW	417	depends on XEN_BACKEND
	418	help
	419	The block-device backend driver allows the kernel to export its
	420	block devices to other guests via a high-performance shared-memory
	421	interface.
	422
a4c34858 KRW	423	The corresponding Linux frontend driver is enabled by the
	424	CONFIG_XEN_BLKDEV_FRONTEND configuration option.
	425
	426	The backend driver attaches itself to a any block device specified
	427	in the XenBus configuration. There are no limits to what the block
	428	device as long as it has a major and minor.
	429
	430	If you are compiling a kernel to run in a Xen block backend driver
	431	domain (often this is domain 0) you should say Y here. To
	432	compile this driver as a module, chose M here: the module
	433	will be called xen-blkback.
	434
	435
e467cde2	436	config VIRTIO_BLK
b8977285 KC	437	tristate "Virtio block driver"
b8977285 KC	438	depends on VIRTIO
e467cde2	439	---help---
0ad07ec1	440	This is the virtual block driver for virtio. It can be used with
ecda85e7	441	QEMU based VMMs (like KVM or Xen). Say Y or M.
e467cde2	442
97b50a65 CH	443	config VIRTIO_BLK_SCSI
	444	bool "SCSI passthrough request for the Virtio block driver"
	445	depends on VIRTIO_BLK
	446	select BLK_SCSI_REQUEST
	447	---help---
	448	Enable support for SCSI passthrough (e.g. the SG_IO ioctl) on
	449	virtio-blk devices. This is only supported for the legacy
	450	virtio protocol and not enabled by default by any hypervisor.
543b334d	451	You probably want to use virtio-scsi instead.
97b50a65	452
602adf40 YS	453	config BLK_DEV_RBD
602adf40 YS	454	tristate "Rados block device (RBD)"
b8977285	455	depends on INET && BLOCK
602adf40 YS	456	select CEPH_LIB
	457	select LIBCRC32C
	458	select CRYPTO_AES
	459	select CRYPTO
	460	default n
	461	help
	462	Say Y here if you want include the Rados block device, which stripes
	463	a block device over objects stored in the Ceph distributed object
	464	store.
	465
	466	More information at http://ceph.newdream.net/.
	467
	468	If unsure, say N.
	469
8722ff8c	470	config BLK_DEV_RSXX
f730e3dc	471	tristate "IBM Flash Adapter 900GB Full Height PCIe Device Driver"
8722ff8c	472	depends on PCI
	473	help
	474	Device driver for IBM's high speed PCIe SSD
f730e3dc	475	storage device: Flash Adapter 900GB Full Height.
8722ff8c	476
	477	To compile this driver as a module, choose M here: the
	478	module will be called rsxx.
	479
fd11d171	480	endif # BLK_DEV