[deliverable/linux.git] / drivers / block / Kconfig

#
# 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_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 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 BLK_DEV_XD
	tristate "XT hard disk support"
	depends on ISA && ISA_DMA_API
	select CHECK_SIGNATURE
	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 && VIRT_TO_BUS
	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 && PROC_FS
	depends on SCSI=y || SCSI=BLK_CPQ_CISS_DA
	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.

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
	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.

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.

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 bytes.  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 CDROM_PKTCDVD
	tristate "Packet writing on CD/DVD media"
	depends on !UML
	help
	  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 (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.

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
	help
	  Include support for the Xilinx SystemACE CompactFlash interface

config XEN_BLKDEV_FRONTEND
	tristate "Xen virtual block device support"
	depends on XEN
	default y
	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.

endif # BLK_DEV
Commit	Line	Data
1da177e4 LT	1	#
	2	# Block device driver configuration
	3	#
	4
fd11d171 JE	5	menuconfig BLK_DEV
	6	bool "Block devices"
	7	depends on BLOCK
	8	default y
06bfb7eb JE	9	---help---
	10	Say Y here to get to see options for various different block device
	11	drivers. This option alone does not add any kernel code.
	12
	13	If you say N, all options in this submenu will be skipped and disabled;
	14	only do this if you know what you are doing.
9361401e	15
fd11d171	16	if BLK_DEV
1da177e4 LT	17
	18	config BLK_DEV_FD
	19	tristate "Normal floppy disk support"
a08b6b79	20	depends on ARCH_MAY_HAVE_PC_FDC
1da177e4 LT	21	---help---
	22	If you want to use the floppy disk drive(s) of your PC under Linux,
	23	say Y. Information about this driver, especially important for IBM
	24	Thinkpad users, is contained in <file:Documentation/floppy.txt>.
	25	That file also contains the location of the Floppy driver FAQ as
	26	well as location of the fdutils package used to configure additional
	27	parameters of the driver at run time.
	28
	29	To compile this driver as a module, choose M here: the
	30	module will be called floppy.
	31
	32	config AMIGA_FLOPPY
	33	tristate "Amiga floppy support"
	34	depends on AMIGA
	35
	36	config ATARI_FLOPPY
	37	tristate "Atari floppy support"
	38	depends on ATARI
	39
1da177e4 LT	40	config MAC_FLOPPY
	41	tristate "Support for PowerMac floppy"
	42	depends on PPC_PMAC && !PPC_PMAC64
	43	help
	44	If you have a SWIM-3 (Super Woz Integrated Machine 3; from Apple)
	45	floppy controller, say Y here. Most commonly found in PowerMacs.
	46
	47	config BLK_DEV_PS2
	48	tristate "PS/2 ESDI hard disk support"
	49	depends on MCA && MCA_LEGACY && BROKEN
	50	help
	51	Say Y here if you have a PS/2 machine with a MCA bus and an ESDI
	52	hard disk.
	53
	54	To compile this driver as a module, choose M here: the
	55	module will be called ps2esdi.
	56
	57	config AMIGA_Z2RAM
	58	tristate "Amiga Zorro II ramdisk support"
	59	depends on ZORRO
	60	help
	61	This enables support for using Chip RAM and Zorro II RAM as a
	62	ramdisk or as a swap partition. Say Y if you want to include this
	63	driver in the kernel.
	64
	65	To compile this driver as a module, choose M here: the
	66	module will be called z2ram.
	67
1da177e4 LT	68	config BLK_DEV_XD
1da177e4 LT	69	tristate "XT hard disk support"
a5532606	70	depends on ISA && ISA_DMA_API
928923c7	71	select CHECK_SIGNATURE
1da177e4 LT	72	help
	73	Very old 8 bit hard disk controllers used in the IBM XT computer
	74	will be supported if you say Y here.
	75
	76	To compile this driver as a module, choose M here: the
	77	module will be called xd.
	78
	79	It's pretty unlikely that you have one of these: say N.
	80
	81	config PARIDE
	82	tristate "Parallel port IDE device support"
6a19b41b	83	depends on PARPORT_PC
1da177e4 LT	84	---help---
	85	There are many external CD-ROM and disk devices that connect through
	86	your computer's parallel port. Most of them are actually IDE devices
	87	using a parallel port IDE adapter. This option enables the PARIDE
	88	subsystem which contains drivers for many of these external drives.
	89	Read <file:Documentation/paride.txt> for more information.
	90
	91	If you have said Y to the "Parallel-port support" configuration
	92	option, you may share a single port between your printer and other
	93	parallel port devices. Answer Y to build PARIDE support into your
	94	kernel, or M if you would like to build it as a loadable module. If
	95	your parallel port support is in a loadable module, you must build
	96	PARIDE as a module. If you built PARIDE support into your kernel,
	97	you may still build the individual protocol modules and high-level
	98	drivers as loadable modules. If you build this support as a module,
	99	it will be called paride.
	100
	101	To use the PARIDE support, you must say Y or M here and also to at
	102	least one high-level driver (e.g. "Parallel port IDE disks",
	103	"Parallel port ATAPI CD-ROMs", "Parallel port ATAPI disks" etc.) and
	104	to at least one protocol driver (e.g. "ATEN EH-100 protocol",
	105	"MicroSolutions backpack protocol", "DataStor Commuter protocol"
	106	etc.).
	107
	108	source "drivers/block/paride/Kconfig"
	109
	110	config BLK_CPQ_DA
	111	tristate "Compaq SMART2 support"
f057eac0	112	depends on PCI && VIRT_TO_BUS
1da177e4 LT	113	help
	114	This is the driver for Compaq Smart Array controllers. Everyone
	115	using these boards should say Y here. See the file
	116	<file:Documentation/cpqarray.txt> for the current list of boards
	117	supported by this driver, and for further information on the use of
	118	this driver.
	119
	120	config BLK_CPQ_CISS_DA
	121	tristate "Compaq Smart Array 5xxx support"
	122	depends on PCI
	123	help
	124	This is the driver for Compaq Smart Array 5xxx controllers.
	125	Everyone using these boards should say Y here.
	126	See <file:Documentation/cciss.txt> for the current list of
	127	boards supported by this driver, and for further information
	128	on the use of this driver.
	129
	130	config CISS_SCSI_TAPE
	131	bool "SCSI tape drive support for Smart Array 5xxx"
3e29fe83 RD	132	depends on BLK_CPQ_CISS_DA && PROC_FS
3e29fe83 RD	133	depends on SCSI=y \|\| SCSI=BLK_CPQ_CISS_DA
1da177e4 LT	134	help
	135	When enabled (Y), this option allows SCSI tape drives and SCSI medium
	136	changers (tape robots) to be accessed via a Compaq 5xxx array
	137	controller. (See <file:Documentation/cciss.txt> for more details.)
	138
	139	"SCSI support" and "SCSI tape support" must also be enabled for this
	140	option to work.
	141
	142	When this option is disabled (N), the SCSI portion of the driver
	143	is not compiled.
	144
	145	config BLK_DEV_DAC960
	146	tristate "Mylex DAC960/DAC1100 PCI RAID Controller support"
	147	depends on PCI
	148	help
	149	This driver adds support for the Mylex DAC960, AcceleRAID, and
	150	eXtremeRAID PCI RAID controllers. See the file
	151	<file:Documentation/README.DAC960> for further information about
	152	this driver.
	153
	154	To compile this driver as a module, choose M here: the
	155	module will be called DAC960.
	156
	157	config BLK_DEV_UMEM
	158	tristate "Micro Memory MM5415 Battery Backed RAM support (EXPERIMENTAL)"
	159	depends on PCI && EXPERIMENTAL
	160	---help---
	161	Saying Y here will include support for the MM5415 family of
	162	battery backed (Non-volatile) RAM cards.
	163	<http://www.umem.com/>
	164
	165	The cards appear as block devices that can be partitioned into
	166	as many as 15 partitions.
	167
	168	To compile this driver as a module, choose M here: the
	169	module will be called umem.
	170
	171	The umem driver has not yet been allocated a MAJOR number, so
bf6ee0ae	172	one is chosen dynamically.
1da177e4 LT	173
	174	config BLK_DEV_UBD
	175	bool "Virtual block device"
	176	depends on UML
	177	---help---
	178	The User-Mode Linux port includes a driver called UBD which will let
	179	you access arbitrary files on the host computer as block devices.
	180	Unless you know that you do not need such virtual block devices say
	181	Y here.
	182
	183	config BLK_DEV_UBD_SYNC
	184	bool "Always do synchronous disk IO for UBD"
	185	depends on BLK_DEV_UBD
	186	---help---
	187	Writes to the virtual block device are not immediately written to the
	188	host's disk; this may cause problems if, for example, the User-Mode
	189	Linux 'Virtual Machine' uses a journalling filesystem and the host
	190	computer crashes.
	191
	192	Synchronous operation (i.e. always writing data to the host's disk
	193	immediately) is configurable on a per-UBD basis by using a special
	194	kernel command line option. Alternatively, you can say Y here to
	195	turn on synchronous operation by default for all block devices.
	196
	197	If you're running a journalling file system (like reiserfs, for
	198	example) in your virtual machine, you will want to say Y here. If
	199	you care for the safety of the data in your virtual machine, Y is a
	200	wise choice too. In all other cases (for example, if you're just
	201	playing around with User-Mode Linux) you can choose N.
	202
	203	config BLK_DEV_COW_COMMON
	204	bool
	205	default BLK_DEV_UBD
	206
	207	config MMAPPER
	208	tristate "Example IO memory driver (BROKEN)"
	209	depends on UML && BROKEN
	210	---help---
	211	The User-Mode Linux port can provide support for IO Memory
	212	emulation with this option. This allows a host file to be
	213	specified as an I/O region on the kernel command line. That file
	214	will be mapped into UML's kernel address space where a driver can
	215	locate it and do whatever it wants with the memory, including
	216	providing an interface to it for UML processes to use.
	217
	218	For more information, see
	219	<http://user-mode-linux.sourceforge.net/iomem.html>.
	220
	221	If you'd like to be able to provide a simulated IO port space for
	222	User-Mode Linux processes, say Y. If unsure, say N.
	223
	224	config BLK_DEV_LOOP
	225	tristate "Loopback device support"
	226	---help---
	227	Saying Y here will allow you to use a regular file as a block
	228	device; you can then create a file system on that block device and
	229	mount it just as you would mount other block devices such as hard
	230	drive partitions, CD-ROM drives or floppy drives. The loop devices
	231	are block special device files with major number 7 and typically
	232	called /dev/loop0, /dev/loop1 etc.
	233
	234	This is useful if you want to check an ISO 9660 file system before
	235	burning the CD, or if you want to use floppy images without first
	236	writing them to floppy. Furthermore, some Linux distributions avoid
237	the need for a dedicated Linux partition by keeping their complete
238	root file system inside a DOS FAT file using this loop device
239	driver.
240
241	To use the loop device, you need the losetup utility, found in the
242	util-linux package, see
243	<ftp://ftp.kernel.org/pub/linux/utils/util-linux/>.
244
245	The loop device driver can also be used to "hide" a file system in
246	a disk partition, floppy, or regular file, either using encryption
247	(scrambling the data) or steganography (hiding the data in the low
248	bits of, say, a sound file). This is also safe if the file resides
249	on a remote file server.
250
251	There are several ways of encrypting disks. Some of these require
252	kernel patches. The vanilla kernel offers the cryptoloop option
253	and a Device Mapper target (which is superior, as it supports all
254	file systems). If you want to use the cryptoloop, say Y to both
255	LOOP and CRYPTOLOOP, and make sure you have a recent (version 2.12
256	or later) version of util-linux. Additionally, be aware that
257	the cryptoloop is not safe for storing journaled filesystems.
258
259	Note that this loop device has nothing to do with the loopback
260	device used for network connections from the machine to itself.
261
262	To compile this driver as a module, choose M here: the
263	module will be called loop.
264
265	Most users will answer N here.
266
267	config BLK_DEV_CRYPTOLOOP
268	tristate "Cryptoloop Support"
269	select CRYPTO
8df3b0a2	270	select CRYPTO_CBC
1da177e4 LT	271	depends on BLK_DEV_LOOP
	272	---help---
	273	Say Y here if you want to be able to use the ciphers that are
	274	provided by the CryptoAPI as loop transformation. This might be
	275	used as hard disk encryption.
	276
	277	WARNING: This device is not safe for journaled file systems like
	278	ext3 or Reiserfs. Please use the Device Mapper crypto module
	279	instead, which can be configured to be on-disk compatible with the
	280	cryptoloop device.
	281
	282	config BLK_DEV_NBD
	283	tristate "Network block device support"
	284	depends on NET
	285	---help---
	286	Saying Y here will allow your computer to be a client for network
	287	block devices, i.e. it will be able to use block devices exported by
	288	servers (mount file systems on them etc.). Communication between
	289	client and server works over TCP/IP networking, but to the client
	290	program this is hidden: it looks like a regular local file access to
	291	a block device special file such as /dev/nd0.
	292
	293	Network block devices also allows you to run a block-device in
	294	userland (making server and client physically the same computer,
	295	communicating using the loopback network device).
	296
	297	Read <file:Documentation/nbd.txt> for more information, especially
	298	about where to find the server code, which runs in user space and
	299	does not need special kernel support.
	300
	301	Note that this has nothing to do with the network file systems NFS
	302	or Coda; you can say N here even if you intend to use NFS or Coda.
	303
	304	To compile this driver as a module, choose M here: the
	305	module will be called nbd.
	306
	307	If unsure, say N.
	308
	309	config BLK_DEV_SX8
	310	tristate "Promise SATA SX8 support"
	311	depends on PCI
	312	---help---
	313	Saying Y or M here will enable support for the
	314	Promise SATA SX8 controllers.
	315
	316	Use devices /dev/sx8/$N and /dev/sx8/$Np$M.
	317
	318	config BLK_DEV_UB
	319	tristate "Low Performance USB Block driver"
	320	depends on USB
	321	help
	322	This driver supports certain USB attached storage devices
	323	such as flash keys.
	324
a00828e9 PZ	325	If you enable this driver, it is recommended to avoid conflicts
a00828e9 PZ	326	with usb-storage by enabling USB_LIBUSUAL.
1da177e4 LT	327
	328	If unsure, say N.
	329
	330	config BLK_DEV_RAM
	331	tristate "RAM disk support"
	332	---help---
	333	Saying Y here will allow you to use a portion of your RAM memory as
	334	a block device, so that you can make file systems on it, read and
	335	write to it and do all the other things that you can do with normal
	336	block devices (such as hard drives). It is usually used to load and
	337	store a copy of a minimal root file system off of a floppy into RAM
	338	during the initial install of Linux.
	339
	340	Note that the kernel command line option "ramdisk=XX" is now
	341	obsolete. For details, read <file:Documentation/ramdisk.txt>.
	342
	343	To compile this driver as a module, choose M here: the
	344	module will be called rd.
	345
	346	Most normal users won't need the RAM disk functionality, and can
	347	thus say N here.
	348
	349	config BLK_DEV_RAM_COUNT
a687fb18	350	int "Default number of RAM disks"
1da177e4	351	default "16"
a687fb18	352	depends on BLK_DEV_RAM
1da177e4 LT	353	help
	354	The default value is 16 RAM disks. Change this if you know what
	355	are doing. If you boot from a filesystem that needs to be extracted
	356	in memory, you will need at least one RAM disk (e.g. root on cramfs).
	357
	358	config BLK_DEV_RAM_SIZE
	359	int "Default RAM disk size (kbytes)"
	360	depends on BLK_DEV_RAM
	361	default "4096"
	362	help
	363	The default value is 4096 kilobytes. Only change this if you know
cebe0fe7	364	what are you doing.
1da177e4	365
bef317e3 NS	366	config BLK_DEV_RAM_BLOCKSIZE
	367	int "Default RAM disk block size (bytes)"
	368	depends on BLK_DEV_RAM
	369	default "1024"
	370	help
73cf9630	371	The default value is 1024 bytes. PAGE_SIZE is a much more
bef317e3 NS	372	efficient choice however. The default is kept to ensure initrd
	373	setups function - apparently needed by the rd_load_image routine
	374	that supposes the filesystem in the image uses a 1024 blocksize.
	375
1da177e4 LT	376	config CDROM_PKTCDVD
	377	tristate "Packet writing on CD/DVD media"
	378	depends on !UML
	379	help
2d4eeec5 TM	380	If you have a CDROM/DVD drive that supports packet writing, say
	381	Y to include support. It should work with any MMC/Mt Fuji
	382	compliant ATAPI or SCSI drive, which is just about any newer
	383	DVD/CD writer.
1da177e4	384
2d4eeec5 TM	385	Currently only writing to CD-RW, DVD-RW, DVD+RW and DVDRAM discs
2d4eeec5 TM	386	is possible.
1da177e4 LT	387	DVD-RW disks must be in restricted overwrite mode.
1da177e4 LT	388
2d4eeec5 TM	389	See the file <file:Documentation/cdrom/packet-writing.txt>
	390	for further information on the use of this driver.
	391
1da177e4 LT	392	To compile this driver as a module, choose M here: the
	393	module will be called pktcdvd.
	394
	395	config CDROM_PKTCDVD_BUFFERS
	396	int "Free buffers for data gathering"
	397	depends on CDROM_PKTCDVD
	398	default "8"
	399	help
	400	This controls the maximum number of active concurrent packets. More
	401	concurrent packets can increase write performance, but also require
	402	more memory. Each concurrent packet will require approximately 64Kb
e1bc89bc PO	403	of non-swappable kernel memory, memory which will be allocated when
e1bc89bc PO	404	a disc is opened for writing.
1da177e4 LT	405
1da177e4 LT	406	config CDROM_PKTCDVD_WCACHE
b566ccef AB	407	bool "Enable write caching (EXPERIMENTAL)"
b566ccef AB	408	depends on CDROM_PKTCDVD && EXPERIMENTAL
1da177e4 LT	409	help
	410	If enabled, write caching will be set for the CD-R/W device. For now
	411	this option is dangerous unless the CD-RW media is known good, as we
	412	don't do deferred write error handling yet.
	413
1da177e4 LT	414	config ATA_OVER_ETH
	415	tristate "ATA over Ethernet support"
	416	depends on NET
	417	help
	418	This driver provides Support for ATA over Ethernet block
	419	devices like the Coraid EtherDrive (R) Storage Blade.
	420
667ef3c3 DM	421	config SUNVDC
	422	tristate "Sun Virtual Disk Client support"
	423	depends on SUN_LDOMS
	424	help
	425	Support for virtual disk devices as a client under Sun
	426	Logical Domains.
	427
61d48c2c MS	428	source "drivers/s390/block/Kconfig"
61d48c2c MS	429
74489a91 GL	430	config XILINX_SYSACE
	431	tristate "Xilinx SystemACE support"
	432	depends on 4xx
	433	help
	434	Include support for the Xilinx SystemACE CompactFlash interface
	435
9f27ee59 JF	436	config XEN_BLKDEV_FRONTEND
	437	tristate "Xen virtual block device support"
	438	depends on XEN
	439	default y
	440	help
	441	This driver implements the front-end of the Xen virtual
	442	block device driver. It communicates with a back-end driver
	443	in another domain which drives the actual block device.
	444
fd11d171	445	endif # BLK_DEV