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