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
419config BCH_CONST_PARAMS
420 bool
421 help
422 Drivers may select this option to force specific constant
423 values for parameters 'm' (Galois field order) and 't'
424 (error correction capability). Those specific values must
425 be set by declaring default values for symbols BCH_CONST_M
426 and BCH_CONST_T.
427 Doing so will enable extra compiler optimizations,
428 improving encoding and decoding performance up to 2x for
429 usual (m,t) values (typically such that m*t < 200).
430 When this option is selected, the BCH library supports
431 only a single (m,t) configuration. This is mainly useful
432 for NAND flash board drivers requiring known, fixed BCH
433 parameters.
434
435config BCH_CONST_M
436 int
437 range 5 15
438 help
439 Constant value for Galois field order 'm'. If 'k' is the
440 number of data bits to protect, 'm' should be chosen such
441 that (k + m*t) <= 2**m - 1.
442 Drivers should declare a default value for this symbol if
443 they select option BCH_CONST_PARAMS.
444
445config BCH_CONST_T
446 int
447 help
448 Constant value for error correction capability in bits 't'.
449 Drivers should declare a default value for this symbol if
450 they select option BCH_CONST_PARAMS.
451
452#
453# Textsearch support is select'ed if needed
454#
455config TEXTSEARCH
456 bool
457
458config TEXTSEARCH_KMP
459 tristate
460
461config TEXTSEARCH_BM
462 tristate
463
464config TEXTSEARCH_FSM
465 tristate
466
467config BTREE
468 bool
469
470config INTERVAL_TREE
471 bool
472 help
473 Simple, embeddable, interval-tree. Can find the start of an
474 overlapping range in log(n) time and then iterate over all
475 overlapping nodes. The algorithm is implemented as an
476 augmented rbtree.
477
478 See:
479
480 Documentation/core-api/rbtree.rst
481
482 for more information.
483
484config INTERVAL_TREE_SPAN_ITER
485 bool
486 depends on INTERVAL_TREE
487
488config XARRAY_MULTI
489 bool
490 help
491 Support entries which occupy multiple consecutive indices in the
492 XArray.
493
494config ASSOCIATIVE_ARRAY
495 bool
496 help
497 Generic associative array. Can be searched and iterated over whilst
498 it is being modified. It is also reasonably quick to search and
499 modify. The algorithms are non-recursive, and the trees are highly
500 capacious.
501
502 See:
503
504 Documentation/core-api/assoc_array.rst
505
506 for more information.
507
508config HAS_IOMEM
509 bool
510 depends on !NO_IOMEM
511 default y
512
513config HAS_IOPORT
514 bool
515
516config HAS_IOPORT_MAP
517 bool
518 depends on HAS_IOMEM && !NO_IOPORT_MAP
519 default y
520
521source "kernel/dma/Kconfig"
522
523config SGL_ALLOC
524 bool
525 default n
526
527config IOMMU_HELPER
528 bool
529
530config CHECK_SIGNATURE
531 bool
532
533config CPUMASK_OFFSTACK
534 bool "Force CPU masks off stack" if DEBUG_PER_CPU_MAPS
535 help
536 Use dynamic allocation for cpumask_var_t, instead of putting
537 them on the stack. This is a bit more expensive, but avoids
538 stack overflow.
539
540config FORCE_NR_CPUS
541 bool "Set number of CPUs at compile time"
542 depends on SMP && EXPERT && !COMPILE_TEST
543 help
544 Say Yes if you have NR_CPUS set to an actual number of possible
545 CPUs in your system, not to a default value. This forces the core
546 code to rely on compile-time value and optimize kernel routines
547 better.
548
549config CPU_RMAP
550 bool
551 depends on SMP
552
553config DQL
554 bool
555
556config GLOB
557 bool
558# This actually supports modular compilation, but the module overhead
559# is ridiculous for the amount of code involved. Until an out-of-tree
560# driver asks for it, we'll just link it directly it into the kernel
561# when required. Since we're ignoring out-of-tree users, there's also
562# no need bother prompting for a manual decision:
563# prompt "glob_match() function"
564 help
565 This option provides a glob_match function for performing
566 simple text pattern matching. It originated in the ATA code
567 to blacklist particular drive models, but other device drivers
568 may need similar functionality.
569
570 All drivers in the Linux kernel tree that require this function
571 should automatically select this option. Say N unless you
572 are compiling an out-of tree driver which tells you that it
573 depends on this.
574
575config GLOB_SELFTEST
576 tristate "glob self-test on init"
577 depends on GLOB
578 help
579 This option enables a simple self-test of the glob_match
580 function on startup. It is primarily useful for people
581 working on the code to ensure they haven't introduced any
582 regressions.
583
584 It only adds a little bit of code and slows kernel boot (or
585 module load) by a small amount, so you're welcome to play with
586 it, but you probably don't need it.
587
588#
589# Netlink attribute parsing support is select'ed if needed
590#
591config NLATTR
592 bool
593
594#
595# Generic 64-bit atomic support is selected if needed
596#
597config GENERIC_ATOMIC64
598 bool
599
600config LRU_CACHE
601 tristate
602
603config CLZ_TAB
604 bool
605
606config IRQ_POLL
607 bool "IRQ polling library"
608 help
609 Helper library to poll interrupt mitigation using polling.
610
611config MPILIB
612 tristate
613 select CLZ_TAB
614 help
615 Multiprecision maths library from GnuPG.
616 It is used to implement RSA digital signature verification,
617 which is used by IMA/EVM digital signature extension.
618
619config SIGNATURE
620 tristate
621 depends on KEYS
622 select CRYPTO
623 select CRYPTO_SHA1
624 select MPILIB
625 help
626 Digital signature verification. Currently only RSA is supported.
627 Implementation is done using GnuPG MPI library
628
629config DIMLIB
630 bool
631 help
632 Dynamic Interrupt Moderation library.
633 Implements an algorithm for dynamically changing CQ moderation values
634 according to run time performance.
635
636#
637# libfdt files, only selected if needed.
638#
639config LIBFDT
640 bool
641
642config OID_REGISTRY
643 tristate
644 help
645 Enable fast lookup object identifier registry.
646
647config UCS2_STRING
648 tristate
649
650#
651# generic vdso
652#
653source "lib/vdso/Kconfig"
654
655source "lib/fonts/Kconfig"
656
657config SG_SPLIT
658 def_bool n
659 help
660 Provides a helper to split scatterlists into chunks, each chunk being
661 a scatterlist. This should be selected by a driver or an API which
662 whishes to split a scatterlist amongst multiple DMA channels.
663
664config SG_POOL
665 def_bool n
666 help
667 Provides a helper to allocate chained scatterlists. This should be
668 selected by a driver or an API which whishes to allocate chained
669 scatterlist.
670
671#
672# sg chaining option
673#
674
675config ARCH_NO_SG_CHAIN
676 def_bool n
677
678config ARCH_HAS_PMEM_API
679 bool
680
681config MEMREGION
682 bool
683
684config ARCH_HAS_CPU_CACHE_INVALIDATE_MEMREGION
685 bool
686
687config ARCH_HAS_MEMREMAP_COMPAT_ALIGN
688 bool
689
690# use memcpy to implement user copies for nommu architectures
691config UACCESS_MEMCPY
692 bool
693
694config ARCH_HAS_UACCESS_FLUSHCACHE
695 bool
696
697# arch has a concept of a recoverable synchronous exception due to a
698# memory-read error like x86 machine-check or ARM data-abort, and
699# implements copy_mc_to_{user,kernel} to abort and report
700# 'bytes-transferred' if that exception fires when accessing the source
701# buffer.
702config ARCH_HAS_COPY_MC
703 bool
704
705# Temporary. Goes away when all archs are cleaned up
706config ARCH_STACKWALK
707 bool
708
709config STACKDEPOT
710 bool
711 select STACKTRACE
712
713config STACKDEPOT_ALWAYS_INIT
714 bool
715 select STACKDEPOT
716
717config REF_TRACKER
718 bool
719 depends on STACKTRACE_SUPPORT
720 select STACKDEPOT
721
722config SBITMAP
723 bool
724
725config PARMAN
726 tristate "parman" if COMPILE_TEST
727
728config OBJAGG
729 tristate "objagg" if COMPILE_TEST
730
731endmenu
732
733config GENERIC_IOREMAP
734 bool
735
736config GENERIC_LIB_ASHLDI3
737 bool
738
739config GENERIC_LIB_ASHRDI3
740 bool
741
742config GENERIC_LIB_LSHRDI3
743 bool
744
745config GENERIC_LIB_MULDI3
746 bool
747
748config GENERIC_LIB_CMPDI2
749 bool
750
751config GENERIC_LIB_UCMPDI2
752 bool
753
754config GENERIC_LIB_DEVMEM_IS_ALLOWED
755 bool
756
757config PLDMFW
758 bool
759 default n
760
761config ASN1_ENCODER
762 tristate
763
764config POLYNOMIAL
765 tristate