xref: /linux/lib/Kconfig (revision 3932b9ca55b0be314a36d3e84faff3e823c081f5)
1#
2# Library configuration
3#
4
5config BINARY_PRINTF
6	def_bool n
7
8menu "Library routines"
9
10config RAID6_PQ
11	tristate
12
13config BITREVERSE
14	tristate
15
16config RATIONAL
17	boolean
18
19config GENERIC_STRNCPY_FROM_USER
20	bool
21
22config GENERIC_STRNLEN_USER
23	bool
24
25config GENERIC_NET_UTILS
26	bool
27
28config GENERIC_FIND_FIRST_BIT
29	bool
30
31config NO_GENERIC_PCI_IOPORT_MAP
32	bool
33
34config GENERIC_PCI_IOMAP
35	bool
36
37config GENERIC_IOMAP
38	bool
39	select GENERIC_PCI_IOMAP
40
41config GENERIC_IO
42	boolean
43	default n
44
45config STMP_DEVICE
46	bool
47
48config PERCPU_RWSEM
49	boolean
50
51config ARCH_USE_CMPXCHG_LOCKREF
52	bool
53
54config ARCH_HAS_FAST_MULTIPLIER
55	bool
56
57config CRC_CCITT
58	tristate "CRC-CCITT functions"
59	help
60	  This option is provided for the case where no in-kernel-tree
61	  modules require CRC-CCITT functions, but a module built outside
62	  the kernel tree does. Such modules that use library CRC-CCITT
63	  functions require M here.
64
65config CRC16
66	tristate "CRC16 functions"
67	help
68	  This option is provided for the case where no in-kernel-tree
69	  modules require CRC16 functions, but a module built outside
70	  the kernel tree does. Such modules that use library CRC16
71	  functions require M here.
72
73config CRC_T10DIF
74	tristate "CRC calculation for the T10 Data Integrity Field"
75	select CRYPTO
76	select CRYPTO_CRCT10DIF
77	help
78	  This option is only needed if a module that's not in the
79	  kernel tree needs to calculate CRC checks for use with the
80	  SCSI data integrity subsystem.
81
82config CRC_ITU_T
83	tristate "CRC ITU-T V.41 functions"
84	help
85	  This option is provided for the case where no in-kernel-tree
86	  modules require CRC ITU-T V.41 functions, but a module built outside
87	  the kernel tree does. Such modules that use library CRC ITU-T V.41
88	  functions require M here.
89
90config CRC32
91	tristate "CRC32/CRC32c functions"
92	default y
93	select BITREVERSE
94	help
95	  This option is provided for the case where no in-kernel-tree
96	  modules require CRC32/CRC32c functions, but a module built outside
97	  the kernel tree does. Such modules that use library CRC32/CRC32c
98	  functions require M here.
99
100config CRC32_SELFTEST
101	bool "CRC32 perform self test on init"
102	default n
103	depends on CRC32
104	help
105	  This option enables the CRC32 library functions to perform a
106	  self test on initialization. The self test computes crc32_le
107	  and crc32_be over byte strings with random alignment and length
108	  and computes the total elapsed time and number of bytes processed.
109
110choice
111	prompt "CRC32 implementation"
112	depends on CRC32
113	default CRC32_SLICEBY8
114	help
115	  This option allows a kernel builder to override the default choice
116	  of CRC32 algorithm.  Choose the default ("slice by 8") unless you
117	  know that you need one of the others.
118
119config CRC32_SLICEBY8
120	bool "Slice by 8 bytes"
121	help
122	  Calculate checksum 8 bytes at a time with a clever slicing algorithm.
123	  This is the fastest algorithm, but comes with a 8KiB lookup table.
124	  Most modern processors have enough cache to hold this table without
125	  thrashing the cache.
126
127	  This is the default implementation choice.  Choose this one unless
128	  you have a good reason not to.
129
130config CRC32_SLICEBY4
131	bool "Slice by 4 bytes"
132	help
133	  Calculate checksum 4 bytes at a time with a clever slicing algorithm.
134	  This is a bit slower than slice by 8, but has a smaller 4KiB lookup
135	  table.
136
137	  Only choose this option if you know what you are doing.
138
139config CRC32_SARWATE
140	bool "Sarwate's Algorithm (one byte at a time)"
141	help
142	  Calculate checksum a byte at a time using Sarwate's algorithm.  This
143	  is not particularly fast, but has a small 256 byte lookup table.
144
145	  Only choose this option if you know what you are doing.
146
147config CRC32_BIT
148	bool "Classic Algorithm (one bit at a time)"
149	help
150	  Calculate checksum one bit at a time.  This is VERY slow, but has
151	  no lookup table.  This is provided as a debugging option.
152
153	  Only choose this option if you are debugging crc32.
154
155endchoice
156
157config CRC7
158	tristate "CRC7 functions"
159	help
160	  This option is provided for the case where no in-kernel-tree
161	  modules require CRC7 functions, but a module built outside
162	  the kernel tree does. Such modules that use library CRC7
163	  functions require M here.
164
165config LIBCRC32C
166	tristate "CRC32c (Castagnoli, et al) Cyclic Redundancy-Check"
167	select CRYPTO
168	select CRYPTO_CRC32C
169	help
170	  This option is provided for the case where no in-kernel-tree
171	  modules require CRC32c functions, but a module built outside the
172	  kernel tree does. Such modules that use library CRC32c functions
173	  require M here.  See Castagnoli93.
174	  Module will be libcrc32c.
175
176config CRC8
177	tristate "CRC8 function"
178	help
179	  This option provides CRC8 function. Drivers may select this
180	  when they need to do cyclic redundancy check according CRC8
181	  algorithm. Module will be called crc8.
182
183config AUDIT_GENERIC
184	bool
185	depends on AUDIT && !AUDIT_ARCH
186	default y
187
188config AUDIT_ARCH_COMPAT_GENERIC
189	bool
190	default n
191
192config AUDIT_COMPAT_GENERIC
193	bool
194	depends on AUDIT_GENERIC && AUDIT_ARCH_COMPAT_GENERIC && COMPAT
195	default y
196
197config RANDOM32_SELFTEST
198	bool "PRNG perform self test on init"
199	default n
200	help
201	  This option enables the 32 bit PRNG library functions to perform a
202	  self test on initialization.
203
204#
205# compression support is select'ed if needed
206#
207config ZLIB_INFLATE
208	tristate
209
210config ZLIB_DEFLATE
211	tristate
212
213config LZO_COMPRESS
214	tristate
215
216config LZO_DECOMPRESS
217	tristate
218
219config LZ4_COMPRESS
220	tristate
221
222config LZ4HC_COMPRESS
223	tristate
224
225config LZ4_DECOMPRESS
226	tristate
227
228source "lib/xz/Kconfig"
229
230#
231# These all provide a common interface (hence the apparent duplication with
232# ZLIB_INFLATE; DECOMPRESS_GZIP is just a wrapper.)
233#
234config DECOMPRESS_GZIP
235	select ZLIB_INFLATE
236	tristate
237
238config DECOMPRESS_BZIP2
239	tristate
240
241config DECOMPRESS_LZMA
242	tristate
243
244config DECOMPRESS_XZ
245	select XZ_DEC
246	tristate
247
248config DECOMPRESS_LZO
249	select LZO_DECOMPRESS
250	tristate
251
252config DECOMPRESS_LZ4
253	select LZ4_DECOMPRESS
254	tristate
255
256#
257# Generic allocator support is selected if needed
258#
259config GENERIC_ALLOCATOR
260	boolean
261
262#
263# reed solomon support is select'ed if needed
264#
265config REED_SOLOMON
266	tristate
267
268config REED_SOLOMON_ENC8
269	boolean
270
271config REED_SOLOMON_DEC8
272	boolean
273
274config REED_SOLOMON_ENC16
275	boolean
276
277config REED_SOLOMON_DEC16
278	boolean
279
280#
281# BCH support is selected if needed
282#
283config BCH
284	tristate
285
286config BCH_CONST_PARAMS
287	boolean
288	help
289	  Drivers may select this option to force specific constant
290	  values for parameters 'm' (Galois field order) and 't'
291	  (error correction capability). Those specific values must
292	  be set by declaring default values for symbols BCH_CONST_M
293	  and BCH_CONST_T.
294	  Doing so will enable extra compiler optimizations,
295	  improving encoding and decoding performance up to 2x for
296	  usual (m,t) values (typically such that m*t < 200).
297	  When this option is selected, the BCH library supports
298	  only a single (m,t) configuration. This is mainly useful
299	  for NAND flash board drivers requiring known, fixed BCH
300	  parameters.
301
302config BCH_CONST_M
303	int
304	range 5 15
305	help
306	  Constant value for Galois field order 'm'. If 'k' is the
307	  number of data bits to protect, 'm' should be chosen such
308	  that (k + m*t) <= 2**m - 1.
309	  Drivers should declare a default value for this symbol if
310	  they select option BCH_CONST_PARAMS.
311
312config BCH_CONST_T
313	int
314	help
315	  Constant value for error correction capability in bits 't'.
316	  Drivers should declare a default value for this symbol if
317	  they select option BCH_CONST_PARAMS.
318
319#
320# Textsearch support is select'ed if needed
321#
322config TEXTSEARCH
323	boolean
324
325config TEXTSEARCH_KMP
326	tristate
327
328config TEXTSEARCH_BM
329	tristate
330
331config TEXTSEARCH_FSM
332	tristate
333
334config BTREE
335	boolean
336
337config INTERVAL_TREE
338	boolean
339	help
340	  Simple, embeddable, interval-tree. Can find the start of an
341	  overlapping range in log(n) time and then iterate over all
342	  overlapping nodes. The algorithm is implemented as an
343	  augmented rbtree.
344
345	  See:
346
347		Documentation/rbtree.txt
348
349	  for more information.
350
351config ASSOCIATIVE_ARRAY
352	bool
353	help
354	  Generic associative array.  Can be searched and iterated over whilst
355	  it is being modified.  It is also reasonably quick to search and
356	  modify.  The algorithms are non-recursive, and the trees are highly
357	  capacious.
358
359	  See:
360
361		Documentation/assoc_array.txt
362
363	  for more information.
364
365config HAS_IOMEM
366	boolean
367	depends on !NO_IOMEM
368	select GENERIC_IO
369	default y
370
371config HAS_IOPORT_MAP
372	boolean
373	depends on HAS_IOMEM && !NO_IOPORT_MAP
374	default y
375
376config HAS_DMA
377	boolean
378	depends on !NO_DMA
379	default y
380
381config CHECK_SIGNATURE
382	bool
383
384config CPUMASK_OFFSTACK
385	bool "Force CPU masks off stack" if DEBUG_PER_CPU_MAPS
386	help
387	  Use dynamic allocation for cpumask_var_t, instead of putting
388	  them on the stack.  This is a bit more expensive, but avoids
389	  stack overflow.
390
391config DISABLE_OBSOLETE_CPUMASK_FUNCTIONS
392       bool "Disable obsolete cpumask functions" if DEBUG_PER_CPU_MAPS
393       depends on BROKEN
394
395config CPU_RMAP
396	bool
397	depends on SMP
398
399config DQL
400	bool
401
402config GLOB
403	bool
404#	This actually supports modular compilation, but the module overhead
405#	is ridiculous for the amount of code involved.	Until an out-of-tree
406#	driver asks for it, we'll just link it directly it into the kernel
407#	when required.  Since we're ignoring out-of-tree users,	there's also
408#	no need bother prompting for a manual decision:
409#	prompt "glob_match() function"
410	help
411	  This option provides a glob_match function for performing
412	  simple text pattern matching.  It originated in the ATA code
413	  to blacklist particular drive models, but other device drivers
414	  may need similar functionality.
415
416	  All drivers in the Linux kernel tree that require this function
417	  should automatically select this option.  Say N unless you
418	  are compiling an out-of tree driver which tells you that it
419	  depends on this.
420
421config GLOB_SELFTEST
422	bool "glob self-test on init"
423	default n
424	depends on GLOB
425	help
426	  This option enables a simple self-test of the glob_match
427	  function on startup.	It is primarily useful for people
428	  working on the code to ensure they haven't introduced any
429	  regressions.
430
431	  It only adds a little bit of code and slows kernel boot (or
432	  module load) by a small amount, so you're welcome to play with
433	  it, but you probably don't need it.
434
435#
436# Netlink attribute parsing support is select'ed if needed
437#
438config NLATTR
439	bool
440
441#
442# Generic 64-bit atomic support is selected if needed
443#
444config GENERIC_ATOMIC64
445       bool
446
447config ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
448	def_bool y if GENERIC_ATOMIC64
449
450config LRU_CACHE
451	tristate
452
453config AVERAGE
454	bool "Averaging functions"
455	help
456	  This option is provided for the case where no in-kernel-tree
457	  modules require averaging functions, but a module built outside
458	  the kernel tree does. Such modules that use library averaging
459	  functions require Y here.
460
461	  If unsure, say N.
462
463config CLZ_TAB
464	bool
465
466config CORDIC
467	tristate "CORDIC algorithm"
468	help
469	  This option provides an implementation of the CORDIC algorithm;
470	  calculations are in fixed point. Module will be called cordic.
471
472config DDR
473	bool "JEDEC DDR data"
474	help
475	  Data from JEDEC specs for DDR SDRAM memories,
476	  particularly the AC timing parameters and addressing
477	  information. This data is useful for drivers handling
478	  DDR SDRAM controllers.
479
480config MPILIB
481	tristate
482	select CLZ_TAB
483	help
484	  Multiprecision maths library from GnuPG.
485	  It is used to implement RSA digital signature verification,
486	  which is used by IMA/EVM digital signature extension.
487
488config SIGNATURE
489	tristate
490	depends on KEYS
491	select CRYPTO
492	select CRYPTO_SHA1
493	select MPILIB
494	help
495	  Digital signature verification. Currently only RSA is supported.
496	  Implementation is done using GnuPG MPI library
497
498#
499# libfdt files, only selected if needed.
500#
501config LIBFDT
502	bool
503
504config OID_REGISTRY
505	tristate
506	help
507	  Enable fast lookup object identifier registry.
508
509config UCS2_STRING
510        tristate
511
512source "lib/fonts/Kconfig"
513
514#
515# sg chaining option
516#
517
518config ARCH_HAS_SG_CHAIN
519	def_bool n
520
521endmenu
522