xref: /openbmc/linux/drivers/block/Kconfig (revision e40573a4)
1# SPDX-License-Identifier: GPL-2.0
2#
3# Block device driver configuration
4#
5
6menuconfig BLK_DEV
7	bool "Block devices"
8	depends on BLOCK
9	default y
10	help
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.
16
17if BLK_DEV
18
19source "drivers/block/null_blk/Kconfig"
20
21config BLK_DEV_FD
22	tristate "Normal floppy disk support"
23	depends on ARCH_MAY_HAVE_PC_FDC
24	help
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.
32
33	  To compile this driver as a module, choose M here: the
34	  module will be called floppy.
35
36config BLK_DEV_FD_RAWCMD
37	bool "Support for raw floppy disk commands (DEPRECATED)"
38	depends on BLK_DEV_FD
39	help
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.
43
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.
46
47	  Note: FDRAWCMD is deprecated and will be removed from the kernel
48	  in the near future.
49
50	  If unsure, say N.
51
52config AMIGA_FLOPPY
53	tristate "Amiga floppy support"
54	depends on AMIGA
55
56config ATARI_FLOPPY
57	tristate "Atari floppy support"
58	depends on ATARI
59
60config MAC_FLOPPY
61	tristate "Support for PowerMac floppy"
62	depends on PPC_PMAC && !PPC_PMAC64
63	help
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.
66
67config BLK_DEV_SWIM
68	tristate "Support for SWIM Macintosh floppy"
69	depends on M68K && MAC && !HIGHMEM
70	help
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.
73
74config AMIGA_Z2RAM
75	tristate "Amiga Zorro II ramdisk support"
76	depends on ZORRO
77	help
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
80	  driver in the kernel.
81
82	  To compile this driver as a module, choose M here: the
83	  module will be called z2ram.
84
85config N64CART
86	bool "N64 cart support"
87	depends on MACH_NINTENDO64
88	help
89	  Support for the N64 cart.
90
91config CDROM
92	tristate
93
94config GDROM
95	tristate "SEGA Dreamcast GD-ROM drive"
96	depends on SH_DREAMCAST
97	select CDROM
98	help
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.
105
106config PARIDE
107	tristate "Parallel port IDE device support"
108	depends on PARPORT_PC
109	help
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.
115
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.
125
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"
131	  etc.).
132
133source "drivers/block/paride/Kconfig"
134
135source "drivers/block/mtip32xx/Kconfig"
136
137source "drivers/block/zram/Kconfig"
138
139config BLK_DEV_UBD
140	bool "Virtual block device"
141	depends on UML
142	help
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
146          Y here.
147
148config BLK_DEV_UBD_SYNC
149	bool "Always do synchronous disk IO for UBD"
150	depends on BLK_DEV_UBD
151	help
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
155	  computer crashes.
156
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.
161
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.
167
168config BLK_DEV_COW_COMMON
169	bool
170	default BLK_DEV_UBD
171
172config BLK_DEV_LOOP
173	tristate "Loopback device support"
174	help
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.
181
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
187	  driver.
188
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/>.
192
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.
198
199	  Note that this loop device has nothing to do with the loopback
200	  device used for network connections from the machine to itself.
201
202	  To compile this driver as a module, choose M here: the
203	  module will be called loop.
204
205	  Most users will answer N here.
206
207config BLK_DEV_LOOP_MIN_COUNT
208	int "Number of loop devices to pre-create at init time"
209	depends on BLK_DEV_LOOP
210	default 8
211	help
212	  Static number of loop devices to be unconditionally pre-created
213	  at init time.
214
215	  This default value can be overwritten on the kernel command
216	  line or with module-parameter loop.max_loop.
217
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.
221
222source "drivers/block/drbd/Kconfig"
223
224config BLK_DEV_NBD
225	tristate "Network block device support"
226	depends on NET
227	help
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.
234
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).
238
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.
242
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.
245
246	  To compile this driver as a module, choose M here: the
247	  module will be called nbd.
248
249	  If unsure, say N.
250
251config BLK_DEV_RAM
252	tristate "RAM block device support"
253	help
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.
260
261	  Note that the kernel command line option "ramdisk=XX" is now obsolete.
262	  For details, read <file:Documentation/admin-guide/blockdev/ramdisk.rst>.
263
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.
267
268	  Most normal users won't need the RAM disk functionality, and can
269	  thus say N here.
270
271config BLK_DEV_RAM_COUNT
272	int "Default number of RAM disks"
273	default "16"
274	depends on BLK_DEV_RAM
275	help
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).
279
280config BLK_DEV_RAM_SIZE
281	int "Default RAM disk size (kbytes)"
282	depends on BLK_DEV_RAM
283	default "4096"
284	help
285	  The default value is 4096 kilobytes. Only change this if you know
286	  what you are doing.
287
288config CDROM_PKTCDVD
289	tristate "Packet writing on CD/DVD media (DEPRECATED)"
290	depends on !UML
291	depends on SCSI
292	select CDROM
293	help
294	  Note: This driver is deprecated and will be removed from the
295	  kernel in the near future!
296
297	  If you have a CDROM/DVD drive that supports packet writing, say
298	  Y to include support. It should work with any MMC/Mt Fuji
299	  compliant ATAPI or SCSI drive, which is just about any newer
300	  DVD/CD writer.
301
302	  Currently only writing to CD-RW, DVD-RW, DVD+RW and DVDRAM discs
303	  is possible.
304	  DVD-RW disks must be in restricted overwrite mode.
305
306	  See the file <file:Documentation/cdrom/packet-writing.rst>
307	  for further information on the use of this driver.
308
309	  To compile this driver as a module, choose M here: the
310	  module will be called pktcdvd.
311
312config CDROM_PKTCDVD_BUFFERS
313	int "Free buffers for data gathering"
314	depends on CDROM_PKTCDVD
315	default "8"
316	help
317	  This controls the maximum number of active concurrent packets. More
318	  concurrent packets can increase write performance, but also require
319	  more memory. Each concurrent packet will require approximately 64Kb
320	  of non-swappable kernel memory, memory which will be allocated when
321	  a disc is opened for writing.
322
323config CDROM_PKTCDVD_WCACHE
324	bool "Enable write caching"
325	depends on CDROM_PKTCDVD
326	help
327	  If enabled, write caching will be set for the CD-R/W device. For now
328	  this option is dangerous unless the CD-RW media is known good, as we
329	  don't do deferred write error handling yet.
330
331config ATA_OVER_ETH
332	tristate "ATA over Ethernet support"
333	depends on NET
334	help
335	This driver provides Support for ATA over Ethernet block
336	devices like the Coraid EtherDrive (R) Storage Blade.
337
338config SUNVDC
339	tristate "Sun Virtual Disk Client support"
340	depends on SUN_LDOMS
341	help
342	  Support for virtual disk devices as a client under Sun
343	  Logical Domains.
344
345source "drivers/s390/block/Kconfig"
346
347config XEN_BLKDEV_FRONTEND
348	tristate "Xen virtual block device support"
349	depends on XEN
350	default y
351	select XEN_XENBUS_FRONTEND
352	help
353	  This driver implements the front-end of the Xen virtual
354	  block device driver.  It communicates with a back-end driver
355	  in another domain which drives the actual block device.
356
357config XEN_BLKDEV_BACKEND
358	tristate "Xen block-device backend driver"
359	depends on XEN_BACKEND
360	help
361	  The block-device backend driver allows the kernel to export its
362	  block devices to other guests via a high-performance shared-memory
363	  interface.
364
365	  The corresponding Linux frontend driver is enabled by the
366	  CONFIG_XEN_BLKDEV_FRONTEND configuration option.
367
368	  The backend driver attaches itself to a any block device specified
369	  in the XenBus configuration. There are no limits to what the block
370	  device as long as it has a major and minor.
371
372	  If you are compiling a kernel to run in a Xen block backend driver
373	  domain (often this is domain 0) you should say Y here. To
374	  compile this driver as a module, chose M here: the module
375	  will be called xen-blkback.
376
377
378config VIRTIO_BLK
379	tristate "Virtio block driver"
380	depends on VIRTIO
381	select SG_POOL
382	help
383	  This is the virtual block driver for virtio.  It can be used with
384          QEMU based VMMs (like KVM or Xen).  Say Y or M.
385
386config BLK_DEV_RBD
387	tristate "Rados block device (RBD)"
388	depends on INET && BLOCK
389	select CEPH_LIB
390	select LIBCRC32C
391	select CRYPTO_AES
392	select CRYPTO
393	help
394	  Say Y here if you want include the Rados block device, which stripes
395	  a block device over objects stored in the Ceph distributed object
396	  store.
397
398	  More information at http://ceph.newdream.net/.
399
400	  If unsure, say N.
401
402config BLK_DEV_UBLK
403	tristate "Userspace block driver (Experimental)"
404	select IO_URING
405	help
406	  io_uring based userspace block driver. Together with ublk server, ublk
407	  has been working well, but interface with userspace or command data
408	  definition isn't finalized yet, and might change according to future
409	  requirement, so mark is as experimental now.
410
411source "drivers/block/rnbd/Kconfig"
412
413endif # BLK_DEV
414