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