Linux kernel mirror (for testing)
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linux
1# SPDX-License-Identifier: GPL-2.0-only
2#
3# Library configuration
4#
5
6config BINARY_PRINTF
7 def_bool n
8
9menu "Library routines"
10
11config RAID6_PQ
12 tristate
13
14config RAID6_PQ_BENCHMARK
15 bool "Automatically choose fastest RAID6 PQ functions"
16 depends on RAID6_PQ
17 default y
18 help
19 Benchmark all available RAID6 PQ functions on init and choose the
20 fastest one.
21
22config LINEAR_RANGES
23 tristate
24
25config PACKING
26 bool "Generic bitfield packing and unpacking"
27 select BITREVERSE
28 default n
29 help
30 This option provides the packing() helper function, which permits
31 converting bitfields between a CPU-usable representation and a
32 memory representation that can have any combination of these quirks:
33 - Is little endian (bytes are reversed within a 32-bit group)
34 - The least-significant 32-bit word comes first (within a 64-bit
35 group)
36 - The most significant bit of a byte is at its right (bit 0 of a
37 register description is numerically 2^7).
38 Drivers may use these helpers to match the bit indices as described
39 in the data sheets of the peripherals they are in control of.
40
41 When in doubt, say N.
42
43config BITREVERSE
44 tristate
45
46config HAVE_ARCH_BITREVERSE
47 bool
48 default n
49 help
50 This option enables the use of hardware bit-reversal instructions on
51 architectures which support such operations.
52
53config ARCH_HAS_STRNCPY_FROM_USER
54 bool
55
56config ARCH_HAS_STRNLEN_USER
57 bool
58
59config GENERIC_STRNCPY_FROM_USER
60 def_bool !ARCH_HAS_STRNCPY_FROM_USER
61
62config GENERIC_STRNLEN_USER
63 def_bool !ARCH_HAS_STRNLEN_USER
64
65config GENERIC_NET_UTILS
66 bool
67
68source "lib/math/Kconfig"
69
70config NO_GENERIC_PCI_IOPORT_MAP
71 bool
72
73config GENERIC_PCI_IOMAP
74 bool
75
76config GENERIC_IOMAP
77 bool
78 select GENERIC_PCI_IOMAP
79
80config STMP_DEVICE
81 bool
82
83config ARCH_USE_CMPXCHG_LOCKREF
84 bool
85
86config ARCH_HAS_FAST_MULTIPLIER
87 bool
88
89config ARCH_USE_SYM_ANNOTATIONS
90 bool
91
92config INDIRECT_PIO
93 bool "Access I/O in non-MMIO mode"
94 depends on ARM64
95 depends on HAS_IOPORT
96 help
97 On some platforms where no separate I/O space exists, there are I/O
98 hosts which can not be accessed in MMIO mode. Using the logical PIO
99 mechanism, the host-local I/O resource can be mapped into system
100 logic PIO space shared with MMIO hosts, such as PCI/PCIe, then the
101 system can access the I/O devices with the mapped-logic PIO through
102 I/O accessors.
103
104 This way has relatively little I/O performance cost. Please make
105 sure your devices really need this configure item enabled.
106
107 When in doubt, say N.
108
109config INDIRECT_IOMEM
110 bool
111 help
112 This is selected by other options/architectures to provide the
113 emulated iomem accessors.
114
115config INDIRECT_IOMEM_FALLBACK
116 bool
117 depends on INDIRECT_IOMEM
118 help
119 If INDIRECT_IOMEM is selected, this enables falling back to plain
120 mmio accesses when the IO memory address is not a registered
121 emulated region.
122
123config TRACE_MMIO_ACCESS
124 bool "Register read/write tracing"
125 depends on TRACING && ARCH_HAVE_TRACE_MMIO_ACCESS
126 help
127 Create tracepoints for MMIO read/write operations. These trace events
128 can be used for logging all MMIO read/write operations.
129
130source "lib/crypto/Kconfig"
131
132config CRC_CCITT
133 tristate "CRC-CCITT functions"
134 help
135 This option is provided for the case where no in-kernel-tree
136 modules require CRC-CCITT functions, but a module built outside
137 the kernel tree does. Such modules that use library CRC-CCITT
138 functions require M here.
139
140config CRC16
141 tristate "CRC16 functions"
142 help
143 This option is provided for the case where no in-kernel-tree
144 modules require CRC16 functions, but a module built outside
145 the kernel tree does. Such modules that use library CRC16
146 functions require M here.
147
148config CRC_T10DIF
149 tristate "CRC calculation for the T10 Data Integrity Field"
150 select CRYPTO
151 select CRYPTO_CRCT10DIF
152 help
153 This option is only needed if a module that's not in the
154 kernel tree needs to calculate CRC checks for use with the
155 SCSI data integrity subsystem.
156
157config CRC64_ROCKSOFT
158 tristate "CRC calculation for the Rocksoft model CRC64"
159 select CRC64
160 select CRYPTO
161 select CRYPTO_CRC64_ROCKSOFT
162 help
163 This option provides a CRC64 API to a registered crypto driver.
164 This is used with the block layer's data integrity subsystem.
165
166config CRC_ITU_T
167 tristate "CRC ITU-T V.41 functions"
168 help
169 This option is provided for the case where no in-kernel-tree
170 modules require CRC ITU-T V.41 functions, but a module built outside
171 the kernel tree does. Such modules that use library CRC ITU-T V.41
172 functions require M here.
173
174config CRC32
175 tristate "CRC32/CRC32c functions"
176 default y
177 select BITREVERSE
178 help
179 This option is provided for the case where no in-kernel-tree
180 modules require CRC32/CRC32c functions, but a module built outside
181 the kernel tree does. Such modules that use library CRC32/CRC32c
182 functions require M here.
183
184config CRC32_SELFTEST
185 tristate "CRC32 perform self test on init"
186 depends on CRC32
187 help
188 This option enables the CRC32 library functions to perform a
189 self test on initialization. The self test computes crc32_le
190 and crc32_be over byte strings with random alignment and length
191 and computes the total elapsed time and number of bytes processed.
192
193choice
194 prompt "CRC32 implementation"
195 depends on CRC32
196 default CRC32_SLICEBY8
197 help
198 This option allows a kernel builder to override the default choice
199 of CRC32 algorithm. Choose the default ("slice by 8") unless you
200 know that you need one of the others.
201
202config CRC32_SLICEBY8
203 bool "Slice by 8 bytes"
204 help
205 Calculate checksum 8 bytes at a time with a clever slicing algorithm.
206 This is the fastest algorithm, but comes with a 8KiB lookup table.
207 Most modern processors have enough cache to hold this table without
208 thrashing the cache.
209
210 This is the default implementation choice. Choose this one unless
211 you have a good reason not to.
212
213config CRC32_SLICEBY4
214 bool "Slice by 4 bytes"
215 help
216 Calculate checksum 4 bytes at a time with a clever slicing algorithm.
217 This is a bit slower than slice by 8, but has a smaller 4KiB lookup
218 table.
219
220 Only choose this option if you know what you are doing.
221
222config CRC32_SARWATE
223 bool "Sarwate's Algorithm (one byte at a time)"
224 help
225 Calculate checksum a byte at a time using Sarwate's algorithm. This
226 is not particularly fast, but has a small 256 byte lookup table.
227
228 Only choose this option if you know what you are doing.
229
230config CRC32_BIT
231 bool "Classic Algorithm (one bit at a time)"
232 help
233 Calculate checksum one bit at a time. This is VERY slow, but has
234 no lookup table. This is provided as a debugging option.
235
236 Only choose this option if you are debugging crc32.
237
238endchoice
239
240config CRC64
241 tristate "CRC64 functions"
242 help
243 This option is provided for the case where no in-kernel-tree
244 modules require CRC64 functions, but a module built outside
245 the kernel tree does. Such modules that use library CRC64
246 functions require M here.
247
248config CRC4
249 tristate "CRC4 functions"
250 help
251 This option is provided for the case where no in-kernel-tree
252 modules require CRC4 functions, but a module built outside
253 the kernel tree does. Such modules that use library CRC4
254 functions require M here.
255
256config CRC7
257 tristate "CRC7 functions"
258 help
259 This option is provided for the case where no in-kernel-tree
260 modules require CRC7 functions, but a module built outside
261 the kernel tree does. Such modules that use library CRC7
262 functions require M here.
263
264config LIBCRC32C
265 tristate "CRC32c (Castagnoli, et al) Cyclic Redundancy-Check"
266 select CRYPTO
267 select CRYPTO_CRC32C
268 help
269 This option is provided for the case where no in-kernel-tree
270 modules require CRC32c functions, but a module built outside the
271 kernel tree does. Such modules that use library CRC32c functions
272 require M here. See Castagnoli93.
273 Module will be libcrc32c.
274
275config CRC8
276 tristate "CRC8 function"
277 help
278 This option provides CRC8 function. Drivers may select this
279 when they need to do cyclic redundancy check according CRC8
280 algorithm. Module will be called crc8.
281
282config XXHASH
283 tristate
284
285config AUDIT_GENERIC
286 bool
287 depends on AUDIT && !AUDIT_ARCH
288 default y
289
290config AUDIT_ARCH_COMPAT_GENERIC
291 bool
292 default n
293
294config AUDIT_COMPAT_GENERIC
295 bool
296 depends on AUDIT_GENERIC && AUDIT_ARCH_COMPAT_GENERIC && COMPAT
297 default y
298
299config RANDOM32_SELFTEST
300 bool "PRNG perform self test on init"
301 help
302 This option enables the 32 bit PRNG library functions to perform a
303 self test on initialization.
304
305#
306# compression support is select'ed if needed
307#
308config 842_COMPRESS
309 select CRC32
310 tristate
311
312config 842_DECOMPRESS
313 select CRC32
314 tristate
315
316config ZLIB_INFLATE
317 tristate
318
319config ZLIB_DEFLATE
320 tristate
321 select BITREVERSE
322
323config ZLIB_DFLTCC
324 def_bool y
325 depends on S390
326 prompt "Enable s390x DEFLATE CONVERSION CALL support for kernel zlib"
327 help
328 Enable s390x hardware support for zlib in the kernel.
329
330config LZO_COMPRESS
331 tristate
332
333config LZO_DECOMPRESS
334 tristate
335
336config LZ4_COMPRESS
337 tristate
338
339config LZ4HC_COMPRESS
340 tristate
341
342config LZ4_DECOMPRESS
343 tristate
344
345config ZSTD_COMMON
346 select XXHASH
347 tristate
348
349config ZSTD_COMPRESS
350 select ZSTD_COMMON
351 tristate
352
353config ZSTD_DECOMPRESS
354 select ZSTD_COMMON
355 tristate
356
357source "lib/xz/Kconfig"
358
359#
360# These all provide a common interface (hence the apparent duplication with
361# ZLIB_INFLATE; DECOMPRESS_GZIP is just a wrapper.)
362#
363config DECOMPRESS_GZIP
364 select ZLIB_INFLATE
365 tristate
366
367config DECOMPRESS_BZIP2
368 tristate
369
370config DECOMPRESS_LZMA
371 tristate
372
373config DECOMPRESS_XZ
374 select XZ_DEC
375 tristate
376
377config DECOMPRESS_LZO
378 select LZO_DECOMPRESS
379 tristate
380
381config DECOMPRESS_LZ4
382 select LZ4_DECOMPRESS
383 tristate
384
385config DECOMPRESS_ZSTD
386 select ZSTD_DECOMPRESS
387 tristate
388
389#
390# Generic allocator support is selected if needed
391#
392config GENERIC_ALLOCATOR
393 bool
394
395#
396# reed solomon support is select'ed if needed
397#
398config REED_SOLOMON
399 tristate
400
401config REED_SOLOMON_ENC8
402 bool
403
404config REED_SOLOMON_DEC8
405 bool
406
407config REED_SOLOMON_ENC16
408 bool
409
410config REED_SOLOMON_DEC16
411 bool
412
413#
414# BCH support is selected if needed
415#
416config BCH
417 tristate
418 select BITREVERSE
419
420config BCH_CONST_PARAMS
421 bool
422 help
423 Drivers may select this option to force specific constant
424 values for parameters 'm' (Galois field order) and 't'
425 (error correction capability). Those specific values must
426 be set by declaring default values for symbols BCH_CONST_M
427 and BCH_CONST_T.
428 Doing so will enable extra compiler optimizations,
429 improving encoding and decoding performance up to 2x for
430 usual (m,t) values (typically such that m*t < 200).
431 When this option is selected, the BCH library supports
432 only a single (m,t) configuration. This is mainly useful
433 for NAND flash board drivers requiring known, fixed BCH
434 parameters.
435
436config BCH_CONST_M
437 int
438 range 5 15
439 help
440 Constant value for Galois field order 'm'. If 'k' is the
441 number of data bits to protect, 'm' should be chosen such
442 that (k + m*t) <= 2**m - 1.
443 Drivers should declare a default value for this symbol if
444 they select option BCH_CONST_PARAMS.
445
446config BCH_CONST_T
447 int
448 help
449 Constant value for error correction capability in bits 't'.
450 Drivers should declare a default value for this symbol if
451 they select option BCH_CONST_PARAMS.
452
453#
454# Textsearch support is select'ed if needed
455#
456config TEXTSEARCH
457 bool
458
459config TEXTSEARCH_KMP
460 tristate
461
462config TEXTSEARCH_BM
463 tristate
464
465config TEXTSEARCH_FSM
466 tristate
467
468config BTREE
469 bool
470
471config INTERVAL_TREE
472 bool
473 help
474 Simple, embeddable, interval-tree. Can find the start of an
475 overlapping range in log(n) time and then iterate over all
476 overlapping nodes. The algorithm is implemented as an
477 augmented rbtree.
478
479 See:
480
481 Documentation/core-api/rbtree.rst
482
483 for more information.
484
485config INTERVAL_TREE_SPAN_ITER
486 bool
487 depends on INTERVAL_TREE
488
489config XARRAY_MULTI
490 bool
491 help
492 Support entries which occupy multiple consecutive indices in the
493 XArray.
494
495config ASSOCIATIVE_ARRAY
496 bool
497 help
498 Generic associative array. Can be searched and iterated over whilst
499 it is being modified. It is also reasonably quick to search and
500 modify. The algorithms are non-recursive, and the trees are highly
501 capacious.
502
503 See:
504
505 Documentation/core-api/assoc_array.rst
506
507 for more information.
508
509config HAS_IOMEM
510 bool
511 depends on !NO_IOMEM
512 default y
513
514config HAS_IOPORT
515 bool
516
517config HAS_IOPORT_MAP
518 bool
519 depends on HAS_IOMEM && !NO_IOPORT_MAP
520 default y
521
522source "kernel/dma/Kconfig"
523
524config SGL_ALLOC
525 bool
526 default n
527
528config IOMMU_HELPER
529 bool
530
531config CHECK_SIGNATURE
532 bool
533
534config CPUMASK_OFFSTACK
535 bool "Force CPU masks off stack" if DEBUG_PER_CPU_MAPS
536 help
537 Use dynamic allocation for cpumask_var_t, instead of putting
538 them on the stack. This is a bit more expensive, but avoids
539 stack overflow.
540
541config FORCE_NR_CPUS
542 bool "Set number of CPUs at compile time"
543 depends on SMP && EXPERT && !COMPILE_TEST
544 help
545 Say Yes if you have NR_CPUS set to an actual number of possible
546 CPUs in your system, not to a default value. This forces the core
547 code to rely on compile-time value and optimize kernel routines
548 better.
549
550config CPU_RMAP
551 bool
552 depends on SMP
553
554config DQL
555 bool
556
557config GLOB
558 bool
559# This actually supports modular compilation, but the module overhead
560# is ridiculous for the amount of code involved. Until an out-of-tree
561# driver asks for it, we'll just link it directly it into the kernel
562# when required. Since we're ignoring out-of-tree users, there's also
563# no need bother prompting for a manual decision:
564# prompt "glob_match() function"
565 help
566 This option provides a glob_match function for performing
567 simple text pattern matching. It originated in the ATA code
568 to blacklist particular drive models, but other device drivers
569 may need similar functionality.
570
571 All drivers in the Linux kernel tree that require this function
572 should automatically select this option. Say N unless you
573 are compiling an out-of tree driver which tells you that it
574 depends on this.
575
576config GLOB_SELFTEST
577 tristate "glob self-test on init"
578 depends on GLOB
579 help
580 This option enables a simple self-test of the glob_match
581 function on startup. It is primarily useful for people
582 working on the code to ensure they haven't introduced any
583 regressions.
584
585 It only adds a little bit of code and slows kernel boot (or
586 module load) by a small amount, so you're welcome to play with
587 it, but you probably don't need it.
588
589#
590# Netlink attribute parsing support is select'ed if needed
591#
592config NLATTR
593 bool
594
595#
596# Generic 64-bit atomic support is selected if needed
597#
598config GENERIC_ATOMIC64
599 bool
600
601config LRU_CACHE
602 tristate
603
604config CLZ_TAB
605 bool
606
607config IRQ_POLL
608 bool "IRQ polling library"
609 help
610 Helper library to poll interrupt mitigation using polling.
611
612config MPILIB
613 tristate
614 select CLZ_TAB
615 help
616 Multiprecision maths library from GnuPG.
617 It is used to implement RSA digital signature verification,
618 which is used by IMA/EVM digital signature extension.
619
620config SIGNATURE
621 tristate
622 depends on KEYS
623 select CRYPTO
624 select CRYPTO_SHA1
625 select MPILIB
626 help
627 Digital signature verification. Currently only RSA is supported.
628 Implementation is done using GnuPG MPI library
629
630config DIMLIB
631 bool
632 help
633 Dynamic Interrupt Moderation library.
634 Implements an algorithm for dynamically changing CQ moderation values
635 according to run time performance.
636
637#
638# libfdt files, only selected if needed.
639#
640config LIBFDT
641 bool
642
643config OID_REGISTRY
644 tristate
645 help
646 Enable fast lookup object identifier registry.
647
648config UCS2_STRING
649 tristate
650
651#
652# generic vdso
653#
654source "lib/vdso/Kconfig"
655
656source "lib/fonts/Kconfig"
657
658config SG_SPLIT
659 def_bool n
660 help
661 Provides a helper to split scatterlists into chunks, each chunk being
662 a scatterlist. This should be selected by a driver or an API which
663 whishes to split a scatterlist amongst multiple DMA channels.
664
665config SG_POOL
666 def_bool n
667 help
668 Provides a helper to allocate chained scatterlists. This should be
669 selected by a driver or an API which whishes to allocate chained
670 scatterlist.
671
672#
673# sg chaining option
674#
675
676config ARCH_NO_SG_CHAIN
677 def_bool n
678
679config ARCH_HAS_PMEM_API
680 bool
681
682config MEMREGION
683 bool
684
685config ARCH_HAS_CPU_CACHE_INVALIDATE_MEMREGION
686 bool
687
688config ARCH_HAS_MEMREMAP_COMPAT_ALIGN
689 bool
690
691# use memcpy to implement user copies for nommu architectures
692config UACCESS_MEMCPY
693 bool
694
695config ARCH_HAS_UACCESS_FLUSHCACHE
696 bool
697
698# arch has a concept of a recoverable synchronous exception due to a
699# memory-read error like x86 machine-check or ARM data-abort, and
700# implements copy_mc_to_{user,kernel} to abort and report
701# 'bytes-transferred' if that exception fires when accessing the source
702# buffer.
703config ARCH_HAS_COPY_MC
704 bool
705
706# Temporary. Goes away when all archs are cleaned up
707config ARCH_STACKWALK
708 bool
709
710config STACKDEPOT
711 bool
712 select STACKTRACE
713
714config STACKDEPOT_ALWAYS_INIT
715 bool
716 select STACKDEPOT
717
718config REF_TRACKER
719 bool
720 depends on STACKTRACE_SUPPORT
721 select STACKDEPOT
722
723config SBITMAP
724 bool
725
726config PARMAN
727 tristate "parman" if COMPILE_TEST
728
729config OBJAGG
730 tristate "objagg" if COMPILE_TEST
731
732endmenu
733
734config GENERIC_IOREMAP
735 bool
736
737config GENERIC_LIB_ASHLDI3
738 bool
739
740config GENERIC_LIB_ASHRDI3
741 bool
742
743config GENERIC_LIB_LSHRDI3
744 bool
745
746config GENERIC_LIB_MULDI3
747 bool
748
749config GENERIC_LIB_CMPDI2
750 bool
751
752config GENERIC_LIB_UCMPDI2
753 bool
754
755config GENERIC_LIB_DEVMEM_IS_ALLOWED
756 bool
757
758config PLDMFW
759 bool
760 default n
761
762config ASN1_ENCODER
763 tristate
764
765config POLYNOMIAL
766 tristate