2 # Block device driver configuration
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.
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.
18 config BLK_DEV_NULL_BLK
19 tristate "Null test block driver"
22 tristate "Normal floppy disk support"
23 depends on ARCH_MAY_HAVE_PC_FDC
25 If you want to use the floppy disk drive(s) of your PC under Linux,
26 say Y. Information about this driver, especially important for IBM
27 Thinkpad users, is contained in
28 <file:Documentation/blockdev/floppy.txt>.
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.
33 To compile this driver as a module, choose M here: the
34 module will be called floppy.
36 config BLK_DEV_FD_RAWCMD
37 bool "Support for raw floppy disk commands (DEPRECATED)"
40 If you want to use actual physical floppies and expect to do
41 special low-level hardware accesses to them (access and use
42 non-standard formats, for example), then enable this.
44 Note that the code enabled by this option is rarely used and
45 might be unstable or insecure, and distros should not enable it.
47 Note: FDRAWCMD is deprecated and will be removed from the kernel
53 tristate "Amiga floppy support"
57 tristate "Atari floppy support"
61 tristate "Support for PowerMac floppy"
62 depends on PPC_PMAC && !PPC_PMAC64
64 If you have a SWIM-3 (Super Woz Integrated Machine 3; from Apple)
65 floppy controller, say Y here. Most commonly found in PowerMacs.
68 tristate "Support for SWIM Macintosh floppy"
69 depends on M68K && MAC
71 You should select this option if you want floppy support
72 and you don't have a II, IIfx, Q900, Q950 or AV series.
75 tristate "Amiga Zorro II ramdisk support"
78 This enables support for using Chip RAM and Zorro II RAM as a
79 ramdisk or as a swap partition. Say Y if you want to include this
82 To compile this driver as a module, choose M here: the
83 module will be called z2ram.
86 tristate "SEGA Dreamcast GD-ROM drive"
87 depends on SH_DREAMCAST
89 A standard SEGA Dreamcast comes with a modified CD ROM drive called a
90 "GD-ROM" by SEGA to signify it is capable of reading special disks
91 with up to 1 GB of data. This drive will also read standard CD ROM
92 disks. Select this option to access any disks in your GD ROM drive.
93 Most users will want to say "Y" here.
94 You can also build this as a module which will be called gdrom.
97 tristate "Parallel port IDE device support"
100 There are many external CD-ROM and disk devices that connect through
101 your computer's parallel port. Most of them are actually IDE devices
102 using a parallel port IDE adapter. This option enables the PARIDE
103 subsystem which contains drivers for many of these external drives.
104 Read <file:Documentation/blockdev/paride.txt> for more information.
106 If you have said Y to the "Parallel-port support" configuration
107 option, you may share a single port between your printer and other
108 parallel port devices. Answer Y to build PARIDE support into your
109 kernel, or M if you would like to build it as a loadable module. If
110 your parallel port support is in a loadable module, you must build
111 PARIDE as a module. If you built PARIDE support into your kernel,
112 you may still build the individual protocol modules and high-level
113 drivers as loadable modules. If you build this support as a module,
114 it will be called paride.
116 To use the PARIDE support, you must say Y or M here and also to at
117 least one high-level driver (e.g. "Parallel port IDE disks",
118 "Parallel port ATAPI CD-ROMs", "Parallel port ATAPI disks" etc.) and
119 to at least one protocol driver (e.g. "ATEN EH-100 protocol",
120 "MicroSolutions backpack protocol", "DataStor Commuter protocol"
123 source "drivers/block/paride/Kconfig"
125 source "drivers/block/mtip32xx/Kconfig"
127 source "drivers/block/zram/Kconfig"
129 config BLK_CPQ_CISS_DA
130 tristate "Compaq Smart Array 5xxx support"
132 select CHECK_SIGNATURE
134 This is the driver for Compaq Smart Array 5xxx controllers.
135 Everyone using these boards should say Y here.
136 See <file:Documentation/blockdev/cciss.txt> for the current list of
137 boards supported by this driver, and for further information
138 on the use of this driver.
140 config CISS_SCSI_TAPE
141 bool "SCSI tape drive support for Smart Array 5xxx"
142 depends on BLK_CPQ_CISS_DA && PROC_FS
143 depends on SCSI=y || SCSI=BLK_CPQ_CISS_DA
145 When enabled (Y), this option allows SCSI tape drives and SCSI medium
146 changers (tape robots) to be accessed via a Compaq 5xxx array
147 controller. (See <file:Documentation/blockdev/cciss.txt> for more details.)
149 "SCSI support" and "SCSI tape support" must also be enabled for this
152 When this option is disabled (N), the SCSI portion of the driver
155 config BLK_DEV_DAC960
156 tristate "Mylex DAC960/DAC1100 PCI RAID Controller support"
159 This driver adds support for the Mylex DAC960, AcceleRAID, and
160 eXtremeRAID PCI RAID controllers. See the file
161 <file:Documentation/blockdev/README.DAC960> for further information
164 To compile this driver as a module, choose M here: the
165 module will be called DAC960.
168 tristate "Micro Memory MM5415 Battery Backed RAM support"
171 Saying Y here will include support for the MM5415 family of
172 battery backed (Non-volatile) RAM cards.
173 <http://www.umem.com/>
175 The cards appear as block devices that can be partitioned into
176 as many as 15 partitions.
178 To compile this driver as a module, choose M here: the
179 module will be called umem.
181 The umem driver has not yet been allocated a MAJOR number, so
182 one is chosen dynamically.
185 bool "Virtual block device"
188 The User-Mode Linux port includes a driver called UBD which will let
189 you access arbitrary files on the host computer as block devices.
190 Unless you know that you do not need such virtual block devices say
193 config BLK_DEV_UBD_SYNC
194 bool "Always do synchronous disk IO for UBD"
195 depends on BLK_DEV_UBD
197 Writes to the virtual block device are not immediately written to the
198 host's disk; this may cause problems if, for example, the User-Mode
199 Linux 'Virtual Machine' uses a journalling filesystem and the host
202 Synchronous operation (i.e. always writing data to the host's disk
203 immediately) is configurable on a per-UBD basis by using a special
204 kernel command line option. Alternatively, you can say Y here to
205 turn on synchronous operation by default for all block devices.
207 If you're running a journalling file system (like reiserfs, for
208 example) in your virtual machine, you will want to say Y here. If
209 you care for the safety of the data in your virtual machine, Y is a
210 wise choice too. In all other cases (for example, if you're just
211 playing around with User-Mode Linux) you can choose N.
213 config BLK_DEV_COW_COMMON
218 tristate "Loopback device support"
220 Saying Y here will allow you to use a regular file as a block
221 device; you can then create a file system on that block device and
222 mount it just as you would mount other block devices such as hard
223 drive partitions, CD-ROM drives or floppy drives. The loop devices
224 are block special device files with major number 7 and typically
225 called /dev/loop0, /dev/loop1 etc.
227 This is useful if you want to check an ISO 9660 file system before
228 burning the CD, or if you want to use floppy images without first
229 writing them to floppy. Furthermore, some Linux distributions avoid
230 the need for a dedicated Linux partition by keeping their complete
231 root file system inside a DOS FAT file using this loop device
234 To use the loop device, you need the losetup utility, found in the
235 util-linux package, see
236 <ftp://ftp.kernel.org/pub/linux/utils/util-linux/>.
238 The loop device driver can also be used to "hide" a file system in
239 a disk partition, floppy, or regular file, either using encryption
240 (scrambling the data) or steganography (hiding the data in the low
241 bits of, say, a sound file). This is also safe if the file resides
242 on a remote file server.
244 There are several ways of encrypting disks. Some of these require
245 kernel patches. The vanilla kernel offers the cryptoloop option
246 and a Device Mapper target (which is superior, as it supports all
247 file systems). If you want to use the cryptoloop, say Y to both
248 LOOP and CRYPTOLOOP, and make sure you have a recent (version 2.12
249 or later) version of util-linux. Additionally, be aware that
250 the cryptoloop is not safe for storing journaled filesystems.
252 Note that this loop device has nothing to do with the loopback
253 device used for network connections from the machine to itself.
255 To compile this driver as a module, choose M here: the
256 module will be called loop.
258 Most users will answer N here.
260 config BLK_DEV_LOOP_MIN_COUNT
261 int "Number of loop devices to pre-create at init time"
262 depends on BLK_DEV_LOOP
265 Static number of loop devices to be unconditionally pre-created
268 This default value can be overwritten on the kernel command
269 line or with module-parameter loop.max_loop.
271 The historic default is 8. If a late 2011 version of losetup(8)
272 is used, it can be set to 0, since needed loop devices can be
273 dynamically allocated with the /dev/loop-control interface.
275 config BLK_DEV_CRYPTOLOOP
276 tristate "Cryptoloop Support (DEPRECATED)"
279 depends on BLK_DEV_LOOP
281 Say Y here if you want to be able to use the ciphers that are
282 provided by the CryptoAPI as loop transformation. This might be
283 used as hard disk encryption.
285 WARNING: This device is not safe for journaled file systems like
286 ext3 or Reiserfs. Please use the Device Mapper crypto module
287 instead, which can be configured to be on-disk compatible with the
288 cryptoloop device. cryptoloop support will be removed in Linux 5.16.
290 source "drivers/block/drbd/Kconfig"
293 tristate "Network block device support"
296 Saying Y here will allow your computer to be a client for network
297 block devices, i.e. it will be able to use block devices exported by
298 servers (mount file systems on them etc.). Communication between
299 client and server works over TCP/IP networking, but to the client
300 program this is hidden: it looks like a regular local file access to
301 a block device special file such as /dev/nd0.
303 Network block devices also allows you to run a block-device in
304 userland (making server and client physically the same computer,
305 communicating using the loopback network device).
307 Read <file:Documentation/blockdev/nbd.txt> for more information,
308 especially about where to find the server code, which runs in user
309 space and does not need special kernel support.
311 Note that this has nothing to do with the network file systems NFS
312 or Coda; you can say N here even if you intend to use NFS or Coda.
314 To compile this driver as a module, choose M here: the
315 module will be called nbd.
320 tristate "STEC S1120 Block Driver"
324 Saying Y or M here will enable support for the
325 STEC, Inc. S1120 PCIe SSD.
327 Use device /dev/skd$N amd /dev/skd$Np$M.
330 tristate "OSD object-as-blkdev support"
331 depends on SCSI_OSD_ULD
333 Saying Y or M here will allow the exporting of a single SCSI
334 OSD (object-based storage) object as a Linux block device.
336 For example, if you create a 2G object on an OSD device,
337 you can then use this module to present that 2G object as
338 a Linux block device.
340 To compile this driver as a module, choose M here: the
341 module will be called osdblk.
346 tristate "Promise SATA SX8 support"
349 Saying Y or M here will enable support for the
350 Promise SATA SX8 controllers.
352 Use devices /dev/sx8/$N and /dev/sx8/$Np$M.
355 tristate "RAM block device support"
357 Saying Y here will allow you to use a portion of your RAM memory as
358 a block device, so that you can make file systems on it, read and
359 write to it and do all the other things that you can do with normal
360 block devices (such as hard drives). It is usually used to load and
361 store a copy of a minimal root file system off of a floppy into RAM
362 during the initial install of Linux.
364 Note that the kernel command line option "ramdisk=XX" is now obsolete.
365 For details, read <file:Documentation/blockdev/ramdisk.txt>.
367 To compile this driver as a module, choose M here: the
368 module will be called brd. An alias "rd" has been defined
369 for historical reasons.
371 Most normal users won't need the RAM disk functionality, and can
374 config BLK_DEV_RAM_COUNT
375 int "Default number of RAM disks"
377 depends on BLK_DEV_RAM
379 The default value is 16 RAM disks. Change this if you know what you
380 are doing. If you boot from a filesystem that needs to be extracted
381 in memory, you will need at least one RAM disk (e.g. root on cramfs).
383 config BLK_DEV_RAM_SIZE
384 int "Default RAM disk size (kbytes)"
385 depends on BLK_DEV_RAM
388 The default value is 4096 kilobytes. Only change this if you know
391 config BLK_DEV_RAM_DAX
392 bool "Support Direct Access (DAX) to RAM block devices"
393 depends on BLK_DEV_RAM && FS_DAX
396 Support filesystems using DAX to access RAM block devices. This
397 avoids double-buffering data in the page cache before copying it
398 to the block device. Answering Y will slightly enlarge the kernel,
399 and will prevent RAM block device backing store memory from being
400 allocated from highmem (only a problem for highmem systems).
403 tristate "Packet writing on CD/DVD media"
406 If you have a CDROM/DVD drive that supports packet writing, say
407 Y to include support. It should work with any MMC/Mt Fuji
408 compliant ATAPI or SCSI drive, which is just about any newer
411 Currently only writing to CD-RW, DVD-RW, DVD+RW and DVDRAM discs
413 DVD-RW disks must be in restricted overwrite mode.
415 See the file <file:Documentation/cdrom/packet-writing.txt>
416 for further information on the use of this driver.
418 To compile this driver as a module, choose M here: the
419 module will be called pktcdvd.
421 config CDROM_PKTCDVD_BUFFERS
422 int "Free buffers for data gathering"
423 depends on CDROM_PKTCDVD
426 This controls the maximum number of active concurrent packets. More
427 concurrent packets can increase write performance, but also require
428 more memory. Each concurrent packet will require approximately 64Kb
429 of non-swappable kernel memory, memory which will be allocated when
430 a disc is opened for writing.
432 config CDROM_PKTCDVD_WCACHE
433 bool "Enable write caching"
434 depends on CDROM_PKTCDVD
436 If enabled, write caching will be set for the CD-R/W device. For now
437 this option is dangerous unless the CD-RW media is known good, as we
438 don't do deferred write error handling yet.
441 tristate "ATA over Ethernet support"
444 This driver provides Support for ATA over Ethernet block
445 devices like the Coraid EtherDrive (R) Storage Blade.
448 tristate "mGine mflash, gflash support"
449 depends on ARM && GPIOLIB
451 mGine mFlash(gFlash) block device driver
454 int "Size of reserved area before MBR"
458 Define size of reserved area that usually used for boot. Unit is KB.
459 All of the block device operation will be taken this value as start
465 tristate "Sun Virtual Disk Client support"
468 Support for virtual disk devices as a client under Sun
471 source "drivers/s390/block/Kconfig"
474 tristate "Xilinx SystemACE support"
475 depends on 4xx || MICROBLAZE
477 Include support for the Xilinx SystemACE CompactFlash interface
479 config XEN_BLKDEV_FRONTEND
480 tristate "Xen virtual block device support"
483 select XEN_XENBUS_FRONTEND
485 This driver implements the front-end of the Xen virtual
486 block device driver. It communicates with a back-end driver
487 in another domain which drives the actual block device.
489 config XEN_BLKDEV_BACKEND
490 tristate "Xen block-device backend driver"
491 depends on XEN_BACKEND
493 The block-device backend driver allows the kernel to export its
494 block devices to other guests via a high-performance shared-memory
497 The corresponding Linux frontend driver is enabled by the
498 CONFIG_XEN_BLKDEV_FRONTEND configuration option.
500 The backend driver attaches itself to a any block device specified
501 in the XenBus configuration. There are no limits to what the block
502 device as long as it has a major and minor.
504 If you are compiling a kernel to run in a Xen block backend driver
505 domain (often this is domain 0) you should say Y here. To
506 compile this driver as a module, chose M here: the module
507 will be called xen-blkback.
511 tristate "Virtio block driver"
514 This is the virtual block driver for virtio. It can be used with
515 lguest or QEMU based VMMs (like KVM or Xen). Say Y or M.
518 bool "Very old hard disk (MFM/RLL/IDE) driver"
520 depends on !ARM || ARCH_RPC || BROKEN
522 This is a very old hard disk driver that lacks the enhanced
523 functionality of the newer ones.
525 It is required for systems with ancient MFM/RLL/ESDI drives.
530 tristate "Rados block device (RBD)"
531 depends on INET && BLOCK
538 Say Y here if you want include the Rados block device, which stripes
539 a block device over objects stored in the Ceph distributed object
542 More information at http://ceph.newdream.net/.
547 tristate "IBM Flash Adapter 900GB Full Height PCIe Device Driver"
551 Device driver for IBM's high speed PCIe SSD
552 storage device: Flash Adapter 900GB Full Height.
554 To compile this driver as a module, choose M here: the
555 module will be called rsxx.