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