CONFIG_BLK_DEV_FD 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 . 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. This driver is also available as a module ( = code which can be inserted in and removed from the running kernel whenever you want). The module will be called floppy.o. If you want to compile it as a module, say M here and read . CONFIG_BLK_DEV_RAM 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 . If you want to compile this as a module ( = code which can be inserted in and removed from the running kernel whenever you want), say M and read . The module will be called rd.o. Most normal users won't need the RAM disk functionality, and can thus say N here. CONFIG_BLK_DEV_RAM_SIZE The default value is 4096. Only change this if you know what are you doing. If you are using IBM S/390, then set this to 8192. CONFIG_BLK_DEV_INITRD The initial RAM disk is a RAM disk that is loaded by the boot loader (loadlin or lilo) and that is mounted as root before the normal boot procedure. It is typically used to load modules needed to mount the "real" root file system, etc. See for details. CONFIG_BLK_DEV_LOOP 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. 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. If you want to do this, you will first have to acquire and install a kernel patch from , and then you need to say Y to this option. Note that alternative ways to use encrypted file systems are provided by the cfs package, which can be gotten from , and the newer tcfs package, available at . You do not need to say Y here if you want to use one of these. However, using cfs requires saying Y to "NFS file system support" below while using tcfs requires applying a kernel patch. An alternative steganography solution is provided by StegFS, also available from . To use the loop device, you need the losetup utility and a recent version of the mount program, both contained in the util-linux package. The location and current version number of util-linux is contained in the file . Note that this loop device has nothing to do with the loopback device used for network connections from the machine to itself. If you want to compile this driver as a module ( = code which can be inserted in and removed from the running kernel whenever you want), say M here and read . The module will be called loop.o. Most users will answer N here. Micro Memory MM5415 Battery Backed RAM support (EXPERIMENTAL) CONFIG_BLK_DEV_UMEM 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. If you want to compile this driver as a module ( = code which can be inserted in and removed from the running kernel whenever you want), say M here and read Documentation/modules.txt. The module will be called umem.o. The umem driver has not yet been allocated a MAJOR number, so one is chosen dynamically. Use "devfs" or look in /proc/devices for the device number CONFIG_BLK_DEV_NBD 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 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. If you want to compile this driver as a module ( = code which can be inserted in and removed from the running kernel whenever you want), say M here and read . The module will be called nbd.o. If unsure, say N. CONFIG_BLK_DEV_XD Very old 8 bit hard disk controllers used in the IBM XT computer will be supported if you say Y here. If you want to compile the driver as a module ( = code which can be inserted in and removed from the running kernel whenever you want), say M here and read . The module will be called xd.o. It's pretty unlikely that you have one of these: say N. CONFIG_BLK_DEV_PS2 Say Y here if you have a PS/2 machine with a MCA bus and an ESDI hard disk. If you want to compile the driver as a module ( = code which can be inserted in and removed from the running kernel whenever you want), say M here and read . The module will be called ps2esdi.o. CONFIG_BLK_DEV_DAC960 This driver adds support for the Mylex DAC960, AcceleRAID, and eXtremeRAID PCI RAID controllers. See the file for further information about this driver. If you want to compile the driver as a module ( = code which can be inserted in and removed from the running kernel whenever you want), say M here and read . The module will be called DAC960.o. CONFIG_PARIDE 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 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.o. 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.). CONFIG_BLK_CPQ_CISS_DA This is the driver for Compaq Smart Array 5xxx controllers. Everyone using these boards should say Y here. See for the current list of boards supported by this driver, and for further information on the use of this driver. CONFIG_CISS_SCSI_TAPE 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 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_SWIM_IOP Say Y here to support the SWIM (Super Woz Integrated Machine) IOP floppy controller on the Macintosh IIfx and Quadra 900/950. CONFIG_AMIGA_Z2RAM 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. This driver is also available as a module ( = code which can be inserted in and removed from the running kernel whenever you want). The module is called z2ram.o. If you want to compile it as a module, say M here and read . CONFIG_ATARI_ACSI This enables support for the Atari ACSI interface. The driver supports hard disks and CD-ROMs, which have 512-byte sectors, or can be switched to that mode. Due to the ACSI command format, only disks up to 1 GB are supported. Special support for certain ACSI to SCSI adapters, which could relax that, isn't included yet. The ACSI driver is also the basis for certain other drivers for devices attached to the ACSI bus: Atari SLM laser printer, BioNet-100 Ethernet, and PAMsNet Ethernet. If you want to use one of these devices, you need ACSI support, too. This driver is also available as a module ( = code which can be inserted in and removed from the running kernel whenever you want). The module will be called acsi.o. CONFIG_ACSI_MULTI_LUN If you have a ACSI device that supports more than one LUN (Logical Unit Number), e.g. a CD jukebox, you should say Y here so that all will be found by the ACSI driver. An ACSI device with multiple LUNs acts logically like multiple ACSI devices. The vast majority of ACSI devices have only one LUN, and so most people can say N here and should in fact do so, because it is safer. CONFIG_ATARI_SLM If you have an Atari SLM laser printer, say Y to include support for it in the kernel. Otherwise, say N. This driver is also available as a module ( = code which can be inserted in and removed from the running kernel whenever you want). The module will be called acsi_slm.o. Be warned: the driver needs much ST-RAM and can cause problems due to that fact! CONFIG_BLK_CPQ_DA This is the driver for Compaq Smart Array controllers. Everyone using these boards should say Y here. See the file for the current list of boards supported by this driver, and for further information on the use of this driver.