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 default n 28 help 29 This option provides the packing() helper function, which permits 30 converting bitfields between a CPU-usable representation and a 31 memory representation that can have any combination of these quirks: 32 - Is little endian (bytes are reversed within a 32-bit group) 33 - The least-significant 32-bit word comes first (within a 64-bit 34 group) 35 - The most significant bit of a byte is at its right (bit 0 of a 36 register description is numerically 2^7). 37 Drivers may use these helpers to match the bit indices as described 38 in the data sheets of the peripherals they are in control of. 39 40 When in doubt, say N. 41 42config BITREVERSE 43 tristate 44 45config HAVE_ARCH_BITREVERSE 46 bool 47 default n 48 help 49 This option enables the use of hardware bit-reversal instructions on 50 architectures which support such operations. 51 52config ARCH_HAS_STRNCPY_FROM_USER 53 bool 54 55config ARCH_HAS_STRNLEN_USER 56 bool 57 58config GENERIC_STRNCPY_FROM_USER 59 def_bool !ARCH_HAS_STRNCPY_FROM_USER 60 61config GENERIC_STRNLEN_USER 62 def_bool !ARCH_HAS_STRNLEN_USER 63 64config GENERIC_NET_UTILS 65 bool 66 67source "lib/math/Kconfig" 68 69config NO_GENERIC_PCI_IOPORT_MAP 70 bool 71 72config GENERIC_PCI_IOMAP 73 bool 74 75config GENERIC_IOMAP 76 bool 77 select GENERIC_PCI_IOMAP 78 79config STMP_DEVICE 80 bool 81 82config ARCH_USE_CMPXCHG_LOCKREF 83 bool 84 85config ARCH_HAS_FAST_MULTIPLIER 86 bool 87 88config ARCH_USE_SYM_ANNOTATIONS 89 bool 90 91config INDIRECT_PIO 92 bool "Access I/O in non-MMIO mode" 93 depends on ARM64 94 help 95 On some platforms where no separate I/O space exists, there are I/O 96 hosts which can not be accessed in MMIO mode. Using the logical PIO 97 mechanism, the host-local I/O resource can be mapped into system 98 logic PIO space shared with MMIO hosts, such as PCI/PCIe, then the 99 system can access the I/O devices with the mapped-logic PIO through 100 I/O accessors. 101 102 This way has relatively little I/O performance cost. Please make 103 sure your devices really need this configure item enabled. 104 105 When in doubt, say N. 106 107config INDIRECT_IOMEM 108 bool 109 help 110 This is selected by other options/architectures to provide the 111 emulated iomem accessors. 112 113config INDIRECT_IOMEM_FALLBACK 114 bool 115 depends on INDIRECT_IOMEM 116 help 117 If INDIRECT_IOMEM is selected, this enables falling back to plain 118 mmio accesses when the IO memory address is not a registered 119 emulated region. 120 121source "lib/crypto/Kconfig" 122 123config CRC_CCITT 124 tristate "CRC-CCITT functions" 125 help 126 This option is provided for the case where no in-kernel-tree 127 modules require CRC-CCITT functions, but a module built outside 128 the kernel tree does. Such modules that use library CRC-CCITT 129 functions require M here. 130 131config CRC16 132 tristate "CRC16 functions" 133 help 134 This option is provided for the case where no in-kernel-tree 135 modules require CRC16 functions, but a module built outside 136 the kernel tree does. Such modules that use library CRC16 137 functions require M here. 138 139config CRC_T10DIF 140 tristate "CRC calculation for the T10 Data Integrity Field" 141 select CRYPTO 142 select CRYPTO_CRCT10DIF 143 help 144 This option is only needed if a module that's not in the 145 kernel tree needs to calculate CRC checks for use with the 146 SCSI data integrity subsystem. 147 148config CRC64_ROCKSOFT 149 tristate "CRC calculation for the Rocksoft model CRC64" 150 select CRC64 151 select CRYPTO 152 select CRYPTO_CRC64_ROCKSOFT 153 help 154 This option provides a CRC64 API to a registered crypto driver. 155 This is used with the block layer's data integrity subsystem. 156 157config CRC_ITU_T 158 tristate "CRC ITU-T V.41 functions" 159 help 160 This option is provided for the case where no in-kernel-tree 161 modules require CRC ITU-T V.41 functions, but a module built outside 162 the kernel tree does. Such modules that use library CRC ITU-T V.41 163 functions require M here. 164 165config CRC32 166 tristate "CRC32/CRC32c functions" 167 default y 168 select BITREVERSE 169 help 170 This option is provided for the case where no in-kernel-tree 171 modules require CRC32/CRC32c functions, but a module built outside 172 the kernel tree does. Such modules that use library CRC32/CRC32c 173 functions require M here. 174 175config CRC32_SELFTEST 176 tristate "CRC32 perform self test on init" 177 depends on CRC32 178 help 179 This option enables the CRC32 library functions to perform a 180 self test on initialization. The self test computes crc32_le 181 and crc32_be over byte strings with random alignment and length 182 and computes the total elapsed time and number of bytes processed. 183 184choice 185 prompt "CRC32 implementation" 186 depends on CRC32 187 default CRC32_SLICEBY8 188 help 189 This option allows a kernel builder to override the default choice 190 of CRC32 algorithm. Choose the default ("slice by 8") unless you 191 know that you need one of the others. 192 193config CRC32_SLICEBY8 194 bool "Slice by 8 bytes" 195 help 196 Calculate checksum 8 bytes at a time with a clever slicing algorithm. 197 This is the fastest algorithm, but comes with a 8KiB lookup table. 198 Most modern processors have enough cache to hold this table without 199 thrashing the cache. 200 201 This is the default implementation choice. Choose this one unless 202 you have a good reason not to. 203 204config CRC32_SLICEBY4 205 bool "Slice by 4 bytes" 206 help 207 Calculate checksum 4 bytes at a time with a clever slicing algorithm. 208 This is a bit slower than slice by 8, but has a smaller 4KiB lookup 209 table. 210 211 Only choose this option if you know what you are doing. 212 213config CRC32_SARWATE 214 bool "Sarwate's Algorithm (one byte at a time)" 215 help 216 Calculate checksum a byte at a time using Sarwate's algorithm. This 217 is not particularly fast, but has a small 256 byte lookup table. 218 219 Only choose this option if you know what you are doing. 220 221config CRC32_BIT 222 bool "Classic Algorithm (one bit at a time)" 223 help 224 Calculate checksum one bit at a time. This is VERY slow, but has 225 no lookup table. This is provided as a debugging option. 226 227 Only choose this option if you are debugging crc32. 228 229endchoice 230 231config CRC64 232 tristate "CRC64 functions" 233 help 234 This option is provided for the case where no in-kernel-tree 235 modules require CRC64 functions, but a module built outside 236 the kernel tree does. Such modules that use library CRC64 237 functions require M here. 238 239config CRC4 240 tristate "CRC4 functions" 241 help 242 This option is provided for the case where no in-kernel-tree 243 modules require CRC4 functions, but a module built outside 244 the kernel tree does. Such modules that use library CRC4 245 functions require M here. 246 247config CRC7 248 tristate "CRC7 functions" 249 help 250 This option is provided for the case where no in-kernel-tree 251 modules require CRC7 functions, but a module built outside 252 the kernel tree does. Such modules that use library CRC7 253 functions require M here. 254 255config LIBCRC32C 256 tristate "CRC32c (Castagnoli, et al) Cyclic Redundancy-Check" 257 select CRYPTO 258 select CRYPTO_CRC32C 259 help 260 This option is provided for the case where no in-kernel-tree 261 modules require CRC32c functions, but a module built outside the 262 kernel tree does. Such modules that use library CRC32c functions 263 require M here. See Castagnoli93. 264 Module will be libcrc32c. 265 266config CRC8 267 tristate "CRC8 function" 268 help 269 This option provides CRC8 function. Drivers may select this 270 when they need to do cyclic redundancy check according CRC8 271 algorithm. Module will be called crc8. 272 273config XXHASH 274 tristate 275 276config AUDIT_GENERIC 277 bool 278 depends on AUDIT && !AUDIT_ARCH 279 default y 280 281config AUDIT_ARCH_COMPAT_GENERIC 282 bool 283 default n 284 285config AUDIT_COMPAT_GENERIC 286 bool 287 depends on AUDIT_GENERIC && AUDIT_ARCH_COMPAT_GENERIC && COMPAT 288 default y 289 290config RANDOM32_SELFTEST 291 bool "PRNG perform self test on init" 292 help 293 This option enables the 32 bit PRNG library functions to perform a 294 self test on initialization. 295 296# 297# compression support is select'ed if needed 298# 299config 842_COMPRESS 300 select CRC32 301 tristate 302 303config 842_DECOMPRESS 304 select CRC32 305 tristate 306 307config ZLIB_INFLATE 308 tristate 309 310config ZLIB_DEFLATE 311 tristate 312 select BITREVERSE 313 314config ZLIB_DFLTCC 315 def_bool y 316 depends on S390 317 prompt "Enable s390x DEFLATE CONVERSION CALL support for kernel zlib" 318 help 319 Enable s390x hardware support for zlib in the kernel. 320 321config LZO_COMPRESS 322 tristate 323 324config LZO_DECOMPRESS 325 tristate 326 327config LZ4_COMPRESS 328 tristate 329 330config LZ4HC_COMPRESS 331 tristate 332 333config LZ4_DECOMPRESS 334 tristate 335 336config ZSTD_COMPRESS 337 select XXHASH 338 tristate 339 340config ZSTD_DECOMPRESS 341 select XXHASH 342 tristate 343 344source "lib/xz/Kconfig" 345 346# 347# These all provide a common interface (hence the apparent duplication with 348# ZLIB_INFLATE; DECOMPRESS_GZIP is just a wrapper.) 349# 350config DECOMPRESS_GZIP 351 select ZLIB_INFLATE 352 tristate 353 354config DECOMPRESS_BZIP2 355 tristate 356 357config DECOMPRESS_LZMA 358 tristate 359 360config DECOMPRESS_XZ 361 select XZ_DEC 362 tristate 363 364config DECOMPRESS_LZO 365 select LZO_DECOMPRESS 366 tristate 367 368config DECOMPRESS_LZ4 369 select LZ4_DECOMPRESS 370 tristate 371 372config DECOMPRESS_ZSTD 373 select ZSTD_DECOMPRESS 374 tristate 375 376# 377# Generic allocator support is selected if needed 378# 379config GENERIC_ALLOCATOR 380 bool 381 382# 383# reed solomon support is select'ed if needed 384# 385config REED_SOLOMON 386 tristate 387 388config REED_SOLOMON_ENC8 389 bool 390 391config REED_SOLOMON_DEC8 392 bool 393 394config REED_SOLOMON_ENC16 395 bool 396 397config REED_SOLOMON_DEC16 398 bool 399 400# 401# BCH support is selected if needed 402# 403config BCH 404 tristate 405 406config BCH_CONST_PARAMS 407 bool 408 help 409 Drivers may select this option to force specific constant 410 values for parameters 'm' (Galois field order) and 't' 411 (error correction capability). Those specific values must 412 be set by declaring default values for symbols BCH_CONST_M 413 and BCH_CONST_T. 414 Doing so will enable extra compiler optimizations, 415 improving encoding and decoding performance up to 2x for 416 usual (m,t) values (typically such that m*t < 200). 417 When this option is selected, the BCH library supports 418 only a single (m,t) configuration. This is mainly useful 419 for NAND flash board drivers requiring known, fixed BCH 420 parameters. 421 422config BCH_CONST_M 423 int 424 range 5 15 425 help 426 Constant value for Galois field order 'm'. If 'k' is the 427 number of data bits to protect, 'm' should be chosen such 428 that (k + m*t) <= 2**m - 1. 429 Drivers should declare a default value for this symbol if 430 they select option BCH_CONST_PARAMS. 431 432config BCH_CONST_T 433 int 434 help 435 Constant value for error correction capability in bits 't'. 436 Drivers should declare a default value for this symbol if 437 they select option BCH_CONST_PARAMS. 438 439# 440# Textsearch support is select'ed if needed 441# 442config TEXTSEARCH 443 bool 444 445config TEXTSEARCH_KMP 446 tristate 447 448config TEXTSEARCH_BM 449 tristate 450 451config TEXTSEARCH_FSM 452 tristate 453 454config BTREE 455 bool 456 457config INTERVAL_TREE 458 bool 459 help 460 Simple, embeddable, interval-tree. Can find the start of an 461 overlapping range in log(n) time and then iterate over all 462 overlapping nodes. The algorithm is implemented as an 463 augmented rbtree. 464 465 See: 466 467 Documentation/core-api/rbtree.rst 468 469 for more information. 470 471config XARRAY_MULTI 472 bool 473 help 474 Support entries which occupy multiple consecutive indices in the 475 XArray. 476 477config ASSOCIATIVE_ARRAY 478 bool 479 help 480 Generic associative array. Can be searched and iterated over whilst 481 it is being modified. It is also reasonably quick to search and 482 modify. The algorithms are non-recursive, and the trees are highly 483 capacious. 484 485 See: 486 487 Documentation/core-api/assoc_array.rst 488 489 for more information. 490 491config HAS_IOMEM 492 bool 493 depends on !NO_IOMEM 494 default y 495 496config HAS_IOPORT_MAP 497 bool 498 depends on HAS_IOMEM && !NO_IOPORT_MAP 499 default y 500 501source "kernel/dma/Kconfig" 502 503config SGL_ALLOC 504 bool 505 default n 506 507config IOMMU_HELPER 508 bool 509 510config CHECK_SIGNATURE 511 bool 512 513config CPUMASK_OFFSTACK 514 bool "Force CPU masks off stack" if DEBUG_PER_CPU_MAPS 515 help 516 Use dynamic allocation for cpumask_var_t, instead of putting 517 them on the stack. This is a bit more expensive, but avoids 518 stack overflow. 519 520config CPU_RMAP 521 bool 522 depends on SMP 523 524config DQL 525 bool 526 527config GLOB 528 bool 529# This actually supports modular compilation, but the module overhead 530# is ridiculous for the amount of code involved. Until an out-of-tree 531# driver asks for it, we'll just link it directly it into the kernel 532# when required. Since we're ignoring out-of-tree users, there's also 533# no need bother prompting for a manual decision: 534# prompt "glob_match() function" 535 help 536 This option provides a glob_match function for performing 537 simple text pattern matching. It originated in the ATA code 538 to blacklist particular drive models, but other device drivers 539 may need similar functionality. 540 541 All drivers in the Linux kernel tree that require this function 542 should automatically select this option. Say N unless you 543 are compiling an out-of tree driver which tells you that it 544 depends on this. 545 546config GLOB_SELFTEST 547 tristate "glob self-test on init" 548 depends on GLOB 549 help 550 This option enables a simple self-test of the glob_match 551 function on startup. It is primarily useful for people 552 working on the code to ensure they haven't introduced any 553 regressions. 554 555 It only adds a little bit of code and slows kernel boot (or 556 module load) by a small amount, so you're welcome to play with 557 it, but you probably don't need it. 558 559# 560# Netlink attribute parsing support is select'ed if needed 561# 562config NLATTR 563 bool 564 565# 566# Generic 64-bit atomic support is selected if needed 567# 568config GENERIC_ATOMIC64 569 bool 570 571config LRU_CACHE 572 tristate 573 574config CLZ_TAB 575 bool 576 577config IRQ_POLL 578 bool "IRQ polling library" 579 help 580 Helper library to poll interrupt mitigation using polling. 581 582config MPILIB 583 tristate 584 select CLZ_TAB 585 help 586 Multiprecision maths library from GnuPG. 587 It is used to implement RSA digital signature verification, 588 which is used by IMA/EVM digital signature extension. 589 590config SIGNATURE 591 tristate 592 depends on KEYS 593 select CRYPTO 594 select CRYPTO_SHA1 595 select MPILIB 596 help 597 Digital signature verification. Currently only RSA is supported. 598 Implementation is done using GnuPG MPI library 599 600config DIMLIB 601 bool 602 help 603 Dynamic Interrupt Moderation library. 604 Implements an algorithm for dynamically changing CQ moderation values 605 according to run time performance. 606 607# 608# libfdt files, only selected if needed. 609# 610config LIBFDT 611 bool 612 613config OID_REGISTRY 614 tristate 615 help 616 Enable fast lookup object identifier registry. 617 618config UCS2_STRING 619 tristate 620 621# 622# generic vdso 623# 624source "lib/vdso/Kconfig" 625 626source "lib/fonts/Kconfig" 627 628config SG_SPLIT 629 def_bool n 630 help 631 Provides a helper to split scatterlists into chunks, each chunk being 632 a scatterlist. This should be selected by a driver or an API which 633 whishes to split a scatterlist amongst multiple DMA channels. 634 635config SG_POOL 636 def_bool n 637 help 638 Provides a helper to allocate chained scatterlists. This should be 639 selected by a driver or an API which whishes to allocate chained 640 scatterlist. 641 642# 643# sg chaining option 644# 645 646config ARCH_NO_SG_CHAIN 647 def_bool n 648 649config ARCH_HAS_PMEM_API 650 bool 651 652config MEMREGION 653 bool 654 655config ARCH_HAS_MEMREMAP_COMPAT_ALIGN 656 bool 657 658# use memcpy to implement user copies for nommu architectures 659config UACCESS_MEMCPY 660 bool 661 662config ARCH_HAS_UACCESS_FLUSHCACHE 663 bool 664 665# arch has a concept of a recoverable synchronous exception due to a 666# memory-read error like x86 machine-check or ARM data-abort, and 667# implements copy_mc_to_{user,kernel} to abort and report 668# 'bytes-transferred' if that exception fires when accessing the source 669# buffer. 670config ARCH_HAS_COPY_MC 671 bool 672 673# Temporary. Goes away when all archs are cleaned up 674config ARCH_STACKWALK 675 bool 676 677config STACKDEPOT 678 bool 679 select STACKTRACE 680 681config STACKDEPOT_ALWAYS_INIT 682 bool 683 select STACKDEPOT 684 685config STACK_HASH_ORDER 686 int "stack depot hash size (12 => 4KB, 20 => 1024KB)" 687 range 12 20 688 default 20 689 depends on STACKDEPOT 690 help 691 Select the hash size as a power of 2 for the stackdepot hash table. 692 Choose a lower value to reduce the memory impact. 693 694config REF_TRACKER 695 bool 696 depends on STACKTRACE_SUPPORT 697 select STACKDEPOT 698 699config SBITMAP 700 bool 701 702config PARMAN 703 tristate "parman" if COMPILE_TEST 704 705config OBJAGG 706 tristate "objagg" if COMPILE_TEST 707 708endmenu 709 710config GENERIC_IOREMAP 711 bool 712 713config GENERIC_LIB_ASHLDI3 714 bool 715 716config GENERIC_LIB_ASHRDI3 717 bool 718 719config GENERIC_LIB_LSHRDI3 720 bool 721 722config GENERIC_LIB_MULDI3 723 bool 724 725config GENERIC_LIB_CMPDI2 726 bool 727 728config GENERIC_LIB_UCMPDI2 729 bool 730 731config GENERIC_LIB_DEVMEM_IS_ALLOWED 732 bool 733 734config PLDMFW 735 bool 736 default n 737 738config ASN1_ENCODER 739 tristate 740 741config POLYNOMIAL 742 tristate 743