1 # SPDX-License-Identifier: GPL-2.0
3 # Block device driver configuration
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.
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.
19 source "drivers/block/null_blk/Kconfig"
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/admin-guide/blockdev/floppy.rst>.
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 && !HIGHMEM
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 bool "N64 cart support"
87 depends on MACH_NINTENDO64
89 Support for the N64 cart.
95 tristate "SEGA Dreamcast GD-ROM drive"
96 depends on SH_DREAMCAST
99 A standard SEGA Dreamcast comes with a modified CD ROM drive called a
100 "GD-ROM" by SEGA to signify it is capable of reading special disks
101 with up to 1 GB of data. This drive will also read standard CD ROM
102 disks. Select this option to access any disks in your GD ROM drive.
103 Most users will want to say "Y" here.
104 You can also build this as a module which will be called gdrom.
107 tristate "Parallel port IDE device support"
108 depends on PARPORT_PC
110 There are many external CD-ROM and disk devices that connect through
111 your computer's parallel port. Most of them are actually IDE devices
112 using a parallel port IDE adapter. This option enables the PARIDE
113 subsystem which contains drivers for many of these external drives.
114 Read <file:Documentation/admin-guide/blockdev/paride.rst> for more information.
116 If you have said Y to the "Parallel-port support" configuration
117 option, you may share a single port between your printer and other
118 parallel port devices. Answer Y to build PARIDE support into your
119 kernel, or M if you would like to build it as a loadable module. If
120 your parallel port support is in a loadable module, you must build
121 PARIDE as a module. If you built PARIDE support into your kernel,
122 you may still build the individual protocol modules and high-level
123 drivers as loadable modules. If you build this support as a module,
124 it will be called paride.
126 To use the PARIDE support, you must say Y or M here and also to at
127 least one high-level driver (e.g. "Parallel port IDE disks",
128 "Parallel port ATAPI CD-ROMs", "Parallel port ATAPI disks" etc.) and
129 to at least one protocol driver (e.g. "ATEN EH-100 protocol",
130 "MicroSolutions backpack protocol", "DataStor Commuter protocol"
133 source "drivers/block/paride/Kconfig"
135 source "drivers/block/mtip32xx/Kconfig"
137 source "drivers/block/zram/Kconfig"
140 bool "Virtual block device"
143 The User-Mode Linux port includes a driver called UBD which will let
144 you access arbitrary files on the host computer as block devices.
145 Unless you know that you do not need such virtual block devices say
148 config BLK_DEV_UBD_SYNC
149 bool "Always do synchronous disk IO for UBD"
150 depends on BLK_DEV_UBD
152 Writes to the virtual block device are not immediately written to the
153 host's disk; this may cause problems if, for example, the User-Mode
154 Linux 'Virtual Machine' uses a journalling filesystem and the host
157 Synchronous operation (i.e. always writing data to the host's disk
158 immediately) is configurable on a per-UBD basis by using a special
159 kernel command line option. Alternatively, you can say Y here to
160 turn on synchronous operation by default for all block devices.
162 If you're running a journalling file system (like reiserfs, for
163 example) in your virtual machine, you will want to say Y here. If
164 you care for the safety of the data in your virtual machine, Y is a
165 wise choice too. In all other cases (for example, if you're just
166 playing around with User-Mode Linux) you can choose N.
168 config BLK_DEV_COW_COMMON
173 tristate "Loopback device support"
175 Saying Y here will allow you to use a regular file as a block
176 device; you can then create a file system on that block device and
177 mount it just as you would mount other block devices such as hard
178 drive partitions, CD-ROM drives or floppy drives. The loop devices
179 are block special device files with major number 7 and typically
180 called /dev/loop0, /dev/loop1 etc.
182 This is useful if you want to check an ISO 9660 file system before
183 burning the CD, or if you want to use floppy images without first
184 writing them to floppy. Furthermore, some Linux distributions avoid
185 the need for a dedicated Linux partition by keeping their complete
186 root file system inside a DOS FAT file using this loop device
189 To use the loop device, you need the losetup utility, found in the
190 util-linux package, see
191 <https://www.kernel.org/pub/linux/utils/util-linux/>.
193 The loop device driver can also be used to "hide" a file system in
194 a disk partition, floppy, or regular file, either using encryption
195 (scrambling the data) or steganography (hiding the data in the low
196 bits of, say, a sound file). This is also safe if the file resides
197 on a remote file server.
199 Note that this loop device has nothing to do with the loopback
200 device used for network connections from the machine to itself.
202 To compile this driver as a module, choose M here: the
203 module will be called loop.
205 Most users will answer N here.
207 config BLK_DEV_LOOP_MIN_COUNT
208 int "Number of loop devices to pre-create at init time"
209 depends on BLK_DEV_LOOP
212 Static number of loop devices to be unconditionally pre-created
215 This default value can be overwritten on the kernel command
216 line or with module-parameter loop.max_loop.
218 The historic default is 8. If a late 2011 version of losetup(8)
219 is used, it can be set to 0, since needed loop devices can be
220 dynamically allocated with the /dev/loop-control interface.
222 source "drivers/block/drbd/Kconfig"
225 tristate "Network block device support"
228 Saying Y here will allow your computer to be a client for network
229 block devices, i.e. it will be able to use block devices exported by
230 servers (mount file systems on them etc.). Communication between
231 client and server works over TCP/IP networking, but to the client
232 program this is hidden: it looks like a regular local file access to
233 a block device special file such as /dev/nd0.
235 Network block devices also allows you to run a block-device in
236 userland (making server and client physically the same computer,
237 communicating using the loopback network device).
239 Read <file:Documentation/admin-guide/blockdev/nbd.rst> for more information,
240 especially about where to find the server code, which runs in user
241 space and does not need special kernel support.
243 Note that this has nothing to do with the network file systems NFS
244 or Coda; you can say N here even if you intend to use NFS or Coda.
246 To compile this driver as a module, choose M here: the
247 module will be called nbd.
252 tristate "RAM block device support"
254 Saying Y here will allow you to use a portion of your RAM memory as
255 a block device, so that you can make file systems on it, read and
256 write to it and do all the other things that you can do with normal
257 block devices (such as hard drives). It is usually used to load and
258 store a copy of a minimal root file system off of a floppy into RAM
259 during the initial install of Linux.
261 Note that the kernel command line option "ramdisk=XX" is now obsolete.
262 For details, read <file:Documentation/admin-guide/blockdev/ramdisk.rst>.
264 To compile this driver as a module, choose M here: the
265 module will be called brd. An alias "rd" has been defined
266 for historical reasons.
268 Most normal users won't need the RAM disk functionality, and can
271 config BLK_DEV_RAM_COUNT
272 int "Default number of RAM disks"
274 depends on BLK_DEV_RAM
276 The default value is 16 RAM disks. Change this if you know what you
277 are doing. If you boot from a filesystem that needs to be extracted
278 in memory, you will need at least one RAM disk (e.g. root on cramfs).
280 config BLK_DEV_RAM_SIZE
281 int "Default RAM disk size (kbytes)"
282 depends on BLK_DEV_RAM
285 The default value is 4096 kilobytes. Only change this if you know
289 tristate "ATA over Ethernet support"
292 This driver provides Support for ATA over Ethernet block
293 devices like the Coraid EtherDrive (R) Storage Blade.
296 tristate "Sun Virtual Disk Client support"
299 Support for virtual disk devices as a client under Sun
302 source "drivers/s390/block/Kconfig"
304 config XEN_BLKDEV_FRONTEND
305 tristate "Xen virtual block device support"
308 select XEN_XENBUS_FRONTEND
310 This driver implements the front-end of the Xen virtual
311 block device driver. It communicates with a back-end driver
312 in another domain which drives the actual block device.
314 config XEN_BLKDEV_BACKEND
315 tristate "Xen block-device backend driver"
316 depends on XEN_BACKEND
318 The block-device backend driver allows the kernel to export its
319 block devices to other guests via a high-performance shared-memory
322 The corresponding Linux frontend driver is enabled by the
323 CONFIG_XEN_BLKDEV_FRONTEND configuration option.
325 The backend driver attaches itself to a any block device specified
326 in the XenBus configuration. There are no limits to what the block
327 device as long as it has a major and minor.
329 If you are compiling a kernel to run in a Xen block backend driver
330 domain (often this is domain 0) you should say Y here. To
331 compile this driver as a module, chose M here: the module
332 will be called xen-blkback.
336 tristate "Virtio block driver"
340 This is the virtual block driver for virtio. It can be used with
341 QEMU based VMMs (like KVM or Xen). Say Y or M.
344 tristate "Rados block device (RBD)"
345 depends on INET && BLOCK
351 Say Y here if you want include the Rados block device, which stripes
352 a block device over objects stored in the Ceph distributed object
355 More information at http://ceph.newdream.net/.
360 tristate "Userspace block driver (Experimental)"
363 io_uring based userspace block driver. Together with ublk server, ublk
364 has been working well, but interface with userspace or command data
365 definition isn't finalized yet, and might change according to future
366 requirement, so mark is as experimental now.
368 Say Y if you want to get better performance because task_work_add()
369 can be used in IO path for replacing io_uring cmd, which will become
370 shared between IO tasks and ubq daemon, meantime task_work_add() can
371 can handle batch more effectively, but task_work_add() isn't exported
372 for module, so ublk has to be built to kernel.
374 source "drivers/block/rnbd/Kconfig"