[linux-block.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

source "drivers/block/null_blk/Kconfig"

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/admin-guide/blockdev/floppy.rst>.
	  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
	select BLK_SCSI_REQUEST

config GDROM
	tristate "SEGA Dreamcast GD-ROM drive"
	depends on SH_DREAMCAST
	select CDROM
	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/admin-guide/blockdev/paride.rst> 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_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/admin-guide/blockdev/nbd.rst> 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/admin-guide/blockdev/ramdisk.rst>.

	  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.rst>
	  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 BLK_DEV_RBD
	tristate "Rados block device (RBD)"
	depends on INET && BLOCK
	select CEPH_LIB
	select LIBCRC32C
	select CRYPTO_AES
	select CRYPTO
	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
	select CRC32
	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.

source "drivers/block/rnbd/Kconfig"

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
a7f7f624	10	help
06bfb7eb JE	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
eebf34a8	19	source "drivers/block/null_blk/Kconfig"
f2298c04	20
1da177e4 LT	21	config BLK_DEV_FD
1da177e4 LT	22	tristate "Normal floppy disk support"
a08b6b79	23	depends on ARCH_MAY_HAVE_PC_FDC
a7f7f624	24	help
1da177e4 LT	25	If you want to use the floppy disk drive(s) of your PC under Linux,
1da177e4 LT	26	say Y. Information about this driver, especially important for IBM
31c00fc1	27	Thinkpad users, is contained in
e7751617	28	<file:Documentation/admin-guide/blockdev/floppy.rst>.
1da177e4 LT	29	That file also contains the location of the Floppy driver FAQ as
	30	well as location of the fdutils package used to configure additional
	31	parameters of the driver at run time.
	32
	33	To compile this driver as a module, choose M here: the
	34	module will be called floppy.
	35
	36	config AMIGA_FLOPPY
	37	tristate "Amiga floppy support"
	38	depends on AMIGA
	39
	40	config ATARI_FLOPPY
	41	tristate "Atari floppy support"
	42	depends on ATARI
	43
1da177e4 LT	44	config MAC_FLOPPY
	45	tristate "Support for PowerMac floppy"
	46	depends on PPC_PMAC && !PPC_PMAC64
	47	help
	48	If you have a SWIM-3 (Super Woz Integrated Machine 3; from Apple)
	49	floppy controller, say Y here. Most commonly found in PowerMacs.
	50
8852ecd9 LV	51	config BLK_DEV_SWIM
	52	tristate "Support for SWIM Macintosh floppy"
	53	depends on M68K && MAC
	54	help
	55	You should select this option if you want floppy support
	56	and you don't have a II, IIfx, Q900, Q950 or AV series.
	57
1da177e4 LT	58	config AMIGA_Z2RAM
	59	tristate "Amiga Zorro II ramdisk support"
	60	depends on ZORRO
	61	help
	62	This enables support for using Chip RAM and Zorro II RAM as a
	63	ramdisk or as a swap partition. Say Y if you want to include this
	64	driver in the kernel.
	65
	66	To compile this driver as a module, choose M here: the
	67	module will be called z2ram.
	68
2a750166	69	config CDROM
a116895f	70	tristate
4e178c17	71	select BLK_SCSI_REQUEST
2a750166	72
2395e463 RD	73	config GDROM
	74	tristate "SEGA Dreamcast GD-ROM drive"
	75	depends on SH_DREAMCAST
2a750166	76	select CDROM
2395e463 RD	77	help
	78	A standard SEGA Dreamcast comes with a modified CD ROM drive called a
	79	"GD-ROM" by SEGA to signify it is capable of reading special disks
	80	with up to 1 GB of data. This drive will also read standard CD ROM
	81	disks. Select this option to access any disks in your GD ROM drive.
	82	Most users will want to say "Y" here.
	83	You can also build this as a module which will be called gdrom.
	84
1da177e4 LT	85	config PARIDE
1da177e4 LT	86	tristate "Parallel port IDE device support"
6a19b41b	87	depends on PARPORT_PC
a7f7f624	88	help
1da177e4 LT	89	There are many external CD-ROM and disk devices that connect through
	90	your computer's parallel port. Most of them are actually IDE devices
	91	using a parallel port IDE adapter. This option enables the PARIDE
	92	subsystem which contains drivers for many of these external drives.
e7751617	93	Read <file:Documentation/admin-guide/blockdev/paride.rst> for more information.
1da177e4 LT	94
	95	If you have said Y to the "Parallel-port support" configuration
	96	option, you may share a single port between your printer and other
	97	parallel port devices. Answer Y to build PARIDE support into your
	98	kernel, or M if you would like to build it as a loadable module. If
	99	your parallel port support is in a loadable module, you must build
	100	PARIDE as a module. If you built PARIDE support into your kernel,
	101	you may still build the individual protocol modules and high-level
	102	drivers as loadable modules. If you build this support as a module,
	103	it will be called paride.
	104
	105	To use the PARIDE support, you must say Y or M here and also to at
	106	least one high-level driver (e.g. "Parallel port IDE disks",
	107	"Parallel port ATAPI CD-ROMs", "Parallel port ATAPI disks" etc.) and
	108	to at least one protocol driver (e.g. "ATEN EH-100 protocol",
	109	"MicroSolutions backpack protocol", "DataStor Commuter protocol"
	110	etc.).
	111
	112	source "drivers/block/paride/Kconfig"
	113
88523a61 SB	114	source "drivers/block/mtip32xx/Kconfig"
88523a61 SB	115
cd67e10a MK	116	source "drivers/block/zram/Kconfig"
cd67e10a MK	117
1da177e4	118	config BLK_DEV_UMEM
b8977285 KC	119	tristate "Micro Memory MM5415 Battery Backed RAM support"
b8977285 KC	120	depends on PCI
a7f7f624	121	help
1da177e4 LT	122	Saying Y here will include support for the MM5415 family of
	123	battery backed (Non-volatile) RAM cards.
	124	<http://www.umem.com/>
	125
	126	The cards appear as block devices that can be partitioned into
	127	as many as 15 partitions.
	128
	129	To compile this driver as a module, choose M here: the
	130	module will be called umem.
	131
	132	The umem driver has not yet been allocated a MAJOR number, so
bf6ee0ae	133	one is chosen dynamically.
1da177e4 LT	134
	135	config BLK_DEV_UBD
	136	bool "Virtual block device"
	137	depends on UML
a7f7f624	138	help
1da177e4 LT	139	The User-Mode Linux port includes a driver called UBD which will let
	140	you access arbitrary files on the host computer as block devices.
	141	Unless you know that you do not need such virtual block devices say
	142	Y here.
	143
	144	config BLK_DEV_UBD_SYNC
	145	bool "Always do synchronous disk IO for UBD"
	146	depends on BLK_DEV_UBD
a7f7f624	147	help
1da177e4 LT	148	Writes to the virtual block device are not immediately written to the
	149	host's disk; this may cause problems if, for example, the User-Mode
	150	Linux 'Virtual Machine' uses a journalling filesystem and the host
	151	computer crashes.
	152
	153	Synchronous operation (i.e. always writing data to the host's disk
	154	immediately) is configurable on a per-UBD basis by using a special
	155	kernel command line option. Alternatively, you can say Y here to
	156	turn on synchronous operation by default for all block devices.
	157
	158	If you're running a journalling file system (like reiserfs, for
	159	example) in your virtual machine, you will want to say Y here. If
	160	you care for the safety of the data in your virtual machine, Y is a
	161	wise choice too. In all other cases (for example, if you're just
	162	playing around with User-Mode Linux) you can choose N.
	163
	164	config BLK_DEV_COW_COMMON
	165	bool
	166	default BLK_DEV_UBD
	167
1da177e4 LT	168	config BLK_DEV_LOOP
1da177e4 LT	169	tristate "Loopback device support"
a7f7f624	170	help
1da177e4 LT	171	Saying Y here will allow you to use a regular file as a block
	172	device; you can then create a file system on that block device and
	173	mount it just as you would mount other block devices such as hard
	174	drive partitions, CD-ROM drives or floppy drives. The loop devices
	175	are block special device files with major number 7 and typically
	176	called /dev/loop0, /dev/loop1 etc.
	177
	178	This is useful if you want to check an ISO 9660 file system before
	179	burning the CD, or if you want to use floppy images without first
	180	writing them to floppy. Furthermore, some Linux distributions avoid
	181	the need for a dedicated Linux partition by keeping their complete
	182	root file system inside a DOS FAT file using this loop device
	183	driver.
	184
	185	To use the loop device, you need the losetup utility, found in the
	186	util-linux package, see
4f6cce39	187	<https://www.kernel.org/pub/linux/utils/util-linux/>.
1da177e4 LT	188
	189	The loop device driver can also be used to "hide" a file system in
	190	a disk partition, floppy, or regular file, either using encryption
	191	(scrambling the data) or steganography (hiding the data in the low
	192	bits of, say, a sound file). This is also safe if the file resides
	193	on a remote file server.
	194
	195	There are several ways of encrypting disks. Some of these require
	196	kernel patches. The vanilla kernel offers the cryptoloop option
	197	and a Device Mapper target (which is superior, as it supports all
	198	file systems). If you want to use the cryptoloop, say Y to both
	199	LOOP and CRYPTOLOOP, and make sure you have a recent (version 2.12
	200	or later) version of util-linux. Additionally, be aware that
	201	the cryptoloop is not safe for storing journaled filesystems.
	202
	203	Note that this loop device has nothing to do with the loopback
	204	device used for network connections from the machine to itself.
	205
	206	To compile this driver as a module, choose M here: the
	207	module will be called loop.
	208
	209	Most users will answer N here.
	210
d134b00b KS	211	config BLK_DEV_LOOP_MIN_COUNT
	212	int "Number of loop devices to pre-create at init time"
	213	depends on BLK_DEV_LOOP
	214	default 8
	215	help
	216	Static number of loop devices to be unconditionally pre-created
	217	at init time.
	218
	219	This default value can be overwritten on the kernel command
	220	line or with module-parameter loop.max_loop.
	221
	222	The historic default is 8. If a late 2011 version of losetup(8)
	223	is used, it can be set to 0, since needed loop devices can be
	224	dynamically allocated with the /dev/loop-control interface.
	225
1da177e4 LT	226	config BLK_DEV_CRYPTOLOOP
	227	tristate "Cryptoloop Support"
	228	select CRYPTO
8df3b0a2	229	select CRYPTO_CBC
1da177e4	230	depends on BLK_DEV_LOOP
a7f7f624	231	help
1da177e4 LT	232	Say Y here if you want to be able to use the ciphers that are
	233	provided by the CryptoAPI as loop transformation. This might be
	234	used as hard disk encryption.
	235
	236	WARNING: This device is not safe for journaled file systems like
	237	ext3 or Reiserfs. Please use the Device Mapper crypto module
	238	instead, which can be configured to be on-disk compatible with the
	239	cryptoloop device.
	240
b411b363 PR	241	source "drivers/block/drbd/Kconfig"
b411b363 PR	242
1da177e4 LT	243	config BLK_DEV_NBD
	244	tristate "Network block device support"
	245	depends on NET
a7f7f624	246	help
1da177e4 LT	247	Saying Y here will allow your computer to be a client for network
	248	block devices, i.e. it will be able to use block devices exported by
	249	servers (mount file systems on them etc.). Communication between
	250	client and server works over TCP/IP networking, but to the client
	251	program this is hidden: it looks like a regular local file access to
	252	a block device special file such as /dev/nd0.
	253
	254	Network block devices also allows you to run a block-device in
	255	userland (making server and client physically the same computer,
	256	communicating using the loopback network device).
	257
e7751617	258	Read <file:Documentation/admin-guide/blockdev/nbd.rst> for more information,
31c00fc1 RD	259	especially about where to find the server code, which runs in user
31c00fc1 RD	260	space and does not need special kernel support.
1da177e4 LT	261
	262	Note that this has nothing to do with the network file systems NFS
	263	or Coda; you can say N here even if you intend to use NFS or Coda.
	264
	265	To compile this driver as a module, choose M here: the
	266	module will be called nbd.
	267
	268	If unsure, say N.
	269
e67f86b3 AB	270	config BLK_DEV_SKD
	271	tristate "STEC S1120 Block Driver"
	272	depends on PCI
	273	depends on 64BIT
a7f7f624	274	help
e67f86b3 AB	275	Saying Y or M here will enable support for the
	276	STEC, Inc. S1120 PCIe SSD.
	277
	278	Use device /dev/skd$N amd /dev/skd$Np$M.
	279
1da177e4 LT	280	config BLK_DEV_SX8
	281	tristate "Promise SATA SX8 support"
	282	depends on PCI
a7f7f624	283	help
1da177e4 LT	284	Saying Y or M here will enable support for the
	285	Promise SATA SX8 controllers.
	286
	287	Use devices /dev/sx8/$N and /dev/sx8/$Np$M.
1da177e4 LT	288
1da177e4 LT	289	config BLK_DEV_RAM
9db5579b	290	tristate "RAM block device support"
a7f7f624	291	help
1da177e4 LT	292	Saying Y here will allow you to use a portion of your RAM memory as
	293	a block device, so that you can make file systems on it, read and
	294	write to it and do all the other things that you can do with normal
	295	block devices (such as hard drives). It is usually used to load and
	296	store a copy of a minimal root file system off of a floppy into RAM
	297	during the initial install of Linux.
	298
31c00fc1	299	Note that the kernel command line option "ramdisk=XX" is now obsolete.
e7751617	300	For details, read <file:Documentation/admin-guide/blockdev/ramdisk.rst>.
1da177e4 LT	301
1da177e4 LT	302	To compile this driver as a module, choose M here: the
a3b25d9b FF	303	module will be called brd. An alias "rd" has been defined
a3b25d9b FF	304	for historical reasons.
1da177e4 LT	305
	306	Most normal users won't need the RAM disk functionality, and can
	307	thus say N here.
	308
	309	config BLK_DEV_RAM_COUNT
a687fb18	310	int "Default number of RAM disks"
1da177e4	311	default "16"
a687fb18	312	depends on BLK_DEV_RAM
1da177e4	313	help
2e977c85	314	The default value is 16 RAM disks. Change this if you know what you
1da177e4 LT	315	are doing. If you boot from a filesystem that needs to be extracted
	316	in memory, you will need at least one RAM disk (e.g. root on cramfs).
	317
	318	config BLK_DEV_RAM_SIZE
	319	int "Default RAM disk size (kbytes)"
	320	depends on BLK_DEV_RAM
	321	default "4096"
	322	help
	323	The default value is 4096 kilobytes. Only change this if you know
2e977c85	324	what you are doing.
1da177e4	325
1da177e4	326	config CDROM_PKTCDVD
5a8b187c	327	tristate "Packet writing on CD/DVD media (DEPRECATED)"
1da177e4	328	depends on !UML
2a750166	329	select CDROM
72148aec	330	select BLK_SCSI_REQUEST
1da177e4	331	help
5a8b187c JA	332	Note: This driver is deprecated and will be removed from the
	333	kernel in the near future!
	334
2d4eeec5 TM	335	If you have a CDROM/DVD drive that supports packet writing, say
	336	Y to include support. It should work with any MMC/Mt Fuji
	337	compliant ATAPI or SCSI drive, which is just about any newer
	338	DVD/CD writer.
1da177e4	339
2d4eeec5 TM	340	Currently only writing to CD-RW, DVD-RW, DVD+RW and DVDRAM discs
2d4eeec5 TM	341	is possible.
1da177e4 LT	342	DVD-RW disks must be in restricted overwrite mode.
1da177e4 LT	343
8ea61889	344	See the file <file:Documentation/cdrom/packet-writing.rst>
2d4eeec5 TM	345	for further information on the use of this driver.
2d4eeec5 TM	346
1da177e4 LT	347	To compile this driver as a module, choose M here: the
	348	module will be called pktcdvd.
	349
	350	config CDROM_PKTCDVD_BUFFERS
	351	int "Free buffers for data gathering"
	352	depends on CDROM_PKTCDVD
	353	default "8"
	354	help
	355	This controls the maximum number of active concurrent packets. More
	356	concurrent packets can increase write performance, but also require
	357	more memory. Each concurrent packet will require approximately 64Kb
e1bc89bc PO	358	of non-swappable kernel memory, memory which will be allocated when
e1bc89bc PO	359	a disc is opened for writing.
1da177e4 LT	360
1da177e4 LT	361	config CDROM_PKTCDVD_WCACHE
b8977285 KC	362	bool "Enable write caching"
b8977285 KC	363	depends on CDROM_PKTCDVD
1da177e4 LT	364	help
	365	If enabled, write caching will be set for the CD-R/W device. For now
	366	this option is dangerous unless the CD-RW media is known good, as we
	367	don't do deferred write error handling yet.
	368
1da177e4 LT	369	config ATA_OVER_ETH
	370	tristate "ATA over Ethernet support"
	371	depends on NET
	372	help
	373	This driver provides Support for ATA over Ethernet block
	374	devices like the Coraid EtherDrive (R) Storage Blade.
	375
667ef3c3 DM	376	config SUNVDC
	377	tristate "Sun Virtual Disk Client support"
	378	depends on SUN_LDOMS
	379	help
	380	Support for virtual disk devices as a client under Sun
	381	Logical Domains.
	382
61d48c2c MS	383	source "drivers/s390/block/Kconfig"
61d48c2c MS	384
74489a91 GL	385	config XILINX_SYSACE
74489a91 GL	386	tristate "Xilinx SystemACE support"
6fa612b5	387	depends on 4xx \|\| MICROBLAZE
74489a91 GL	388	help
	389	Include support for the Xilinx SystemACE CompactFlash interface
	390
9f27ee59 JF	391	config XEN_BLKDEV_FRONTEND
	392	tristate "Xen virtual block device support"
	393	depends on XEN
	394	default y
2de06cc1	395	select XEN_XENBUS_FRONTEND
9f27ee59 JF	396	help
	397	This driver implements the front-end of the Xen virtual
	398	block device driver. It communicates with a back-end driver
	399	in another domain which drives the actual block device.
	400
dfc07b13	401	config XEN_BLKDEV_BACKEND
ea5e1161	402	tristate "Xen block-device backend driver"
dfc07b13 KRW	403	depends on XEN_BACKEND
	404	help
	405	The block-device backend driver allows the kernel to export its
	406	block devices to other guests via a high-performance shared-memory
	407	interface.
	408
a4c34858 KRW	409	The corresponding Linux frontend driver is enabled by the
	410	CONFIG_XEN_BLKDEV_FRONTEND configuration option.
	411
	412	The backend driver attaches itself to a any block device specified
	413	in the XenBus configuration. There are no limits to what the block
	414	device as long as it has a major and minor.
	415
	416	If you are compiling a kernel to run in a Xen block backend driver
	417	domain (often this is domain 0) you should say Y here. To
	418	compile this driver as a module, chose M here: the module
	419	will be called xen-blkback.
	420
	421
e467cde2	422	config VIRTIO_BLK
b8977285 KC	423	tristate "Virtio block driver"
b8977285 KC	424	depends on VIRTIO
a7f7f624	425	help
0ad07ec1	426	This is the virtual block driver for virtio. It can be used with
ecda85e7	427	QEMU based VMMs (like KVM or Xen). Say Y or M.
e467cde2	428
602adf40 YS	429	config BLK_DEV_RBD
602adf40 YS	430	tristate "Rados block device (RBD)"
b8977285	431	depends on INET && BLOCK
602adf40 YS	432	select CEPH_LIB
	433	select LIBCRC32C
	434	select CRYPTO_AES
	435	select CRYPTO
602adf40 YS	436	help
	437	Say Y here if you want include the Rados block device, which stripes
	438	a block device over objects stored in the Ceph distributed object
	439	store.
	440
	441	More information at http://ceph.newdream.net/.
	442
	443	If unsure, say N.
	444
8722ff8c	445	config BLK_DEV_RSXX
f730e3dc	446	tristate "IBM Flash Adapter 900GB Full Height PCIe Device Driver"
8722ff8c	447	depends on PCI
36a106a4	448	select CRC32
8722ff8c	449	help
8722ff8c	450	Device driver for IBM's high speed PCIe SSD
f730e3dc	451	storage device: Flash Adapter 900GB Full Height.
8722ff8c	452
	453	To compile this driver as a module, choose M here: the
	454	module will be called rsxx.
	455
bc018853 JW	456	source "drivers/block/rnbd/Kconfig"
bc018853 JW	457
fd11d171	458	endif # BLK_DEV