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 PACKING_KUNIT_TEST 44 tristate "KUnit tests for packing library" if !KUNIT_ALL_TESTS 45 depends on PACKING && KUNIT 46 default KUNIT_ALL_TESTS 47 help 48 This builds KUnit tests for the packing library. 49 50 For more information on KUnit and unit tests in general, 51 please refer to the KUnit documentation in Documentation/dev-tools/kunit/. 52 53 When in doubt, say N. 54 55config BITREVERSE 56 tristate 57 58config HAVE_ARCH_BITREVERSE 59 bool 60 default n 61 help 62 This option enables the use of hardware bit-reversal instructions on 63 architectures which support such operations. 64 65config ARCH_HAS_STRNCPY_FROM_USER 66 bool 67 68config ARCH_HAS_STRNLEN_USER 69 bool 70 71config GENERIC_STRNCPY_FROM_USER 72 def_bool !ARCH_HAS_STRNCPY_FROM_USER 73 74config GENERIC_STRNLEN_USER 75 def_bool !ARCH_HAS_STRNLEN_USER 76 77config GENERIC_NET_UTILS 78 bool 79 80source "lib/math/Kconfig" 81 82config NO_GENERIC_PCI_IOPORT_MAP 83 bool 84 85config GENERIC_IOMAP 86 bool 87 select GENERIC_PCI_IOMAP 88 89config STMP_DEVICE 90 bool 91 92config ARCH_USE_CMPXCHG_LOCKREF 93 bool 94 95config ARCH_HAS_FAST_MULTIPLIER 96 bool 97 98config ARCH_USE_SYM_ANNOTATIONS 99 bool 100 101config INDIRECT_PIO 102 bool "Access I/O in non-MMIO mode" 103 depends on ARM64 104 depends on HAS_IOPORT 105 help 106 On some platforms where no separate I/O space exists, there are I/O 107 hosts which can not be accessed in MMIO mode. Using the logical PIO 108 mechanism, the host-local I/O resource can be mapped into system 109 logic PIO space shared with MMIO hosts, such as PCI/PCIe, then the 110 system can access the I/O devices with the mapped-logic PIO through 111 I/O accessors. 112 113 This way has relatively little I/O performance cost. Please make 114 sure your devices really need this configure item enabled. 115 116 When in doubt, say N. 117 118config INDIRECT_IOMEM 119 bool 120 help 121 This is selected by other options/architectures to provide the 122 emulated iomem accessors. 123 124config INDIRECT_IOMEM_FALLBACK 125 bool 126 depends on INDIRECT_IOMEM 127 help 128 If INDIRECT_IOMEM is selected, this enables falling back to plain 129 mmio accesses when the IO memory address is not a registered 130 emulated region. 131 132config TRACE_MMIO_ACCESS 133 bool "Register read/write tracing" 134 depends on TRACING && ARCH_HAVE_TRACE_MMIO_ACCESS 135 help 136 Create tracepoints for MMIO read/write operations. These trace events 137 can be used for logging all MMIO read/write operations. 138 139source "lib/crypto/Kconfig" 140 141config CRC_CCITT 142 tristate "CRC-CCITT functions" 143 help 144 This option is provided for the case where no in-kernel-tree 145 modules require CRC-CCITT functions, but a module built outside 146 the kernel tree does. Such modules that use library CRC-CCITT 147 functions require M here. 148 149config CRC16 150 tristate "CRC16 functions" 151 help 152 This option is provided for the case where no in-kernel-tree 153 modules require CRC16 functions, but a module built outside 154 the kernel tree does. Such modules that use library CRC16 155 functions require M here. 156 157config CRC_T10DIF 158 tristate "CRC calculation for the T10 Data Integrity Field" 159 select CRYPTO 160 select CRYPTO_CRCT10DIF 161 help 162 This option is only needed if a module that's not in the 163 kernel tree needs to calculate CRC checks for use with the 164 SCSI data integrity subsystem. 165 166config CRC64_ROCKSOFT 167 tristate "CRC calculation for the Rocksoft model CRC64" 168 select CRC64 169 select CRYPTO 170 select CRYPTO_CRC64_ROCKSOFT 171 help 172 This option provides a CRC64 API to a registered crypto driver. 173 This is used with the block layer's data integrity subsystem. 174 175config CRC_ITU_T 176 tristate "CRC ITU-T V.41 functions" 177 help 178 This option is provided for the case where no in-kernel-tree 179 modules require CRC ITU-T V.41 functions, but a module built outside 180 the kernel tree does. Such modules that use library CRC ITU-T V.41 181 functions require M here. 182 183config CRC32 184 tristate "CRC32/CRC32c functions" 185 default y 186 select BITREVERSE 187 help 188 This option is provided for the case where no in-kernel-tree 189 modules require CRC32/CRC32c functions, but a module built outside 190 the kernel tree does. Such modules that use library CRC32/CRC32c 191 functions require M here. 192 193config CRC32_SELFTEST 194 tristate "CRC32 perform self test on init" 195 depends on CRC32 196 help 197 This option enables the CRC32 library functions to perform a 198 self test on initialization. The self test computes crc32_le 199 and crc32_be over byte strings with random alignment and length 200 and computes the total elapsed time and number of bytes processed. 201 202choice 203 prompt "CRC32 implementation" 204 depends on CRC32 205 default CRC32_SLICEBY8 206 help 207 This option allows a kernel builder to override the default choice 208 of CRC32 algorithm. Choose the default ("slice by 8") unless you 209 know that you need one of the others. 210 211config CRC32_SLICEBY8 212 bool "Slice by 8 bytes" 213 help 214 Calculate checksum 8 bytes at a time with a clever slicing algorithm. 215 This is the fastest algorithm, but comes with a 8KiB lookup table. 216 Most modern processors have enough cache to hold this table without 217 thrashing the cache. 218 219 This is the default implementation choice. Choose this one unless 220 you have a good reason not to. 221 222config CRC32_SLICEBY4 223 bool "Slice by 4 bytes" 224 help 225 Calculate checksum 4 bytes at a time with a clever slicing algorithm. 226 This is a bit slower than slice by 8, but has a smaller 4KiB lookup 227 table. 228 229 Only choose this option if you know what you are doing. 230 231config CRC32_SARWATE 232 bool "Sarwate's Algorithm (one byte at a time)" 233 help 234 Calculate checksum a byte at a time using Sarwate's algorithm. This 235 is not particularly fast, but has a small 256 byte lookup table. 236 237 Only choose this option if you know what you are doing. 238 239config CRC32_BIT 240 bool "Classic Algorithm (one bit at a time)" 241 help 242 Calculate checksum one bit at a time. This is VERY slow, but has 243 no lookup table. This is provided as a debugging option. 244 245 Only choose this option if you are debugging crc32. 246 247endchoice 248 249config CRC64 250 tristate "CRC64 functions" 251 help 252 This option is provided for the case where no in-kernel-tree 253 modules require CRC64 functions, but a module built outside 254 the kernel tree does. Such modules that use library CRC64 255 functions require M here. 256 257config CRC4 258 tristate "CRC4 functions" 259 help 260 This option is provided for the case where no in-kernel-tree 261 modules require CRC4 functions, but a module built outside 262 the kernel tree does. Such modules that use library CRC4 263 functions require M here. 264 265config CRC7 266 tristate "CRC7 functions" 267 help 268 This option is provided for the case where no in-kernel-tree 269 modules require CRC7 functions, but a module built outside 270 the kernel tree does. Such modules that use library CRC7 271 functions require M here. 272 273config LIBCRC32C 274 tristate "CRC32c (Castagnoli, et al) Cyclic Redundancy-Check" 275 select CRYPTO 276 select CRYPTO_CRC32C 277 help 278 This option is provided for the case where no in-kernel-tree 279 modules require CRC32c functions, but a module built outside the 280 kernel tree does. Such modules that use library CRC32c functions 281 require M here. See Castagnoli93. 282 Module will be libcrc32c. 283 284config CRC8 285 tristate "CRC8 function" 286 help 287 This option provides CRC8 function. Drivers may select this 288 when they need to do cyclic redundancy check according CRC8 289 algorithm. Module will be called crc8. 290 291config XXHASH 292 tristate 293 294config AUDIT_GENERIC 295 bool 296 depends on AUDIT && !AUDIT_ARCH 297 default y 298 299config AUDIT_ARCH_COMPAT_GENERIC 300 bool 301 default n 302 303config AUDIT_COMPAT_GENERIC 304 bool 305 depends on AUDIT_GENERIC && AUDIT_ARCH_COMPAT_GENERIC && COMPAT 306 default y 307 308config RANDOM32_SELFTEST 309 bool "PRNG perform self test on init" 310 help 311 This option enables the 32 bit PRNG library functions to perform a 312 self test on initialization. 313 314# 315# compression support is select'ed if needed 316# 317config 842_COMPRESS 318 select CRC32 319 tristate 320 321config 842_DECOMPRESS 322 select CRC32 323 tristate 324 325config ZLIB_INFLATE 326 tristate 327 328config ZLIB_DEFLATE 329 tristate 330 select BITREVERSE 331 332config ZLIB_DFLTCC 333 def_bool y 334 depends on S390 335 prompt "Enable s390x DEFLATE CONVERSION CALL support for kernel zlib" 336 help 337 Enable s390x hardware support for zlib in the kernel. 338 339config LZO_COMPRESS 340 tristate 341 342config LZO_DECOMPRESS 343 tristate 344 345config LZ4_COMPRESS 346 tristate 347 348config LZ4HC_COMPRESS 349 tristate 350 351config LZ4_DECOMPRESS 352 tristate 353 354config ZSTD_COMMON 355 select XXHASH 356 tristate 357 358config ZSTD_COMPRESS 359 select ZSTD_COMMON 360 tristate 361 362config ZSTD_DECOMPRESS 363 select ZSTD_COMMON 364 tristate 365 366source "lib/xz/Kconfig" 367 368# 369# These all provide a common interface (hence the apparent duplication with 370# ZLIB_INFLATE; DECOMPRESS_GZIP is just a wrapper.) 371# 372config DECOMPRESS_GZIP 373 select ZLIB_INFLATE 374 tristate 375 376config DECOMPRESS_BZIP2 377 tristate 378 379config DECOMPRESS_LZMA 380 tristate 381 382config DECOMPRESS_XZ 383 select XZ_DEC 384 tristate 385 386config DECOMPRESS_LZO 387 select LZO_DECOMPRESS 388 tristate 389 390config DECOMPRESS_LZ4 391 select LZ4_DECOMPRESS 392 tristate 393 394config DECOMPRESS_ZSTD 395 select ZSTD_DECOMPRESS 396 tristate 397 398# 399# Generic allocator support is selected if needed 400# 401config GENERIC_ALLOCATOR 402 bool 403 404# 405# reed solomon support is select'ed if needed 406# 407config REED_SOLOMON 408 tristate 409 410config REED_SOLOMON_ENC8 411 bool 412 413config REED_SOLOMON_DEC8 414 bool 415 416config REED_SOLOMON_ENC16 417 bool 418 419config REED_SOLOMON_DEC16 420 bool 421 422# 423# BCH support is selected if needed 424# 425config BCH 426 tristate 427 select BITREVERSE 428 429config BCH_CONST_PARAMS 430 bool 431 help 432 Drivers may select this option to force specific constant 433 values for parameters 'm' (Galois field order) and 't' 434 (error correction capability). Those specific values must 435 be set by declaring default values for symbols BCH_CONST_M 436 and BCH_CONST_T. 437 Doing so will enable extra compiler optimizations, 438 improving encoding and decoding performance up to 2x for 439 usual (m,t) values (typically such that m*t < 200). 440 When this option is selected, the BCH library supports 441 only a single (m,t) configuration. This is mainly useful 442 for NAND flash board drivers requiring known, fixed BCH 443 parameters. 444 445config BCH_CONST_M 446 int 447 range 5 15 448 help 449 Constant value for Galois field order 'm'. If 'k' is the 450 number of data bits to protect, 'm' should be chosen such 451 that (k + m*t) <= 2**m - 1. 452 Drivers should declare a default value for this symbol if 453 they select option BCH_CONST_PARAMS. 454 455config BCH_CONST_T 456 int 457 help 458 Constant value for error correction capability in bits 't'. 459 Drivers should declare a default value for this symbol if 460 they select option BCH_CONST_PARAMS. 461 462# 463# Textsearch support is select'ed if needed 464# 465config TEXTSEARCH 466 bool 467 468config TEXTSEARCH_KMP 469 tristate 470 471config TEXTSEARCH_BM 472 tristate 473 474config TEXTSEARCH_FSM 475 tristate 476 477config BTREE 478 bool 479 480config INTERVAL_TREE 481 bool 482 help 483 Simple, embeddable, interval-tree. Can find the start of an 484 overlapping range in log(n) time and then iterate over all 485 overlapping nodes. The algorithm is implemented as an 486 augmented rbtree. 487 488 See: 489 490 Documentation/core-api/rbtree.rst 491 492 for more information. 493 494config INTERVAL_TREE_SPAN_ITER 495 bool 496 depends on INTERVAL_TREE 497 498config XARRAY_MULTI 499 bool 500 help 501 Support entries which occupy multiple consecutive indices in the 502 XArray. 503 504config ASSOCIATIVE_ARRAY 505 bool 506 help 507 Generic associative array. Can be searched and iterated over whilst 508 it is being modified. It is also reasonably quick to search and 509 modify. The algorithms are non-recursive, and the trees are highly 510 capacious. 511 512 See: 513 514 Documentation/core-api/assoc_array.rst 515 516 for more information. 517 518config CLOSURES 519 bool 520 521config HAS_IOMEM 522 bool 523 depends on !NO_IOMEM 524 default y 525 526config HAS_IOPORT 527 bool 528 529config HAS_IOPORT_MAP 530 bool 531 depends on HAS_IOMEM && !NO_IOPORT_MAP 532 default y 533 534source "kernel/dma/Kconfig" 535 536config SGL_ALLOC 537 bool 538 default n 539 540config IOMMU_HELPER 541 bool 542 543config CHECK_SIGNATURE 544 bool 545 546config CPUMASK_OFFSTACK 547 bool "Force CPU masks off stack" if DEBUG_PER_CPU_MAPS 548 help 549 Use dynamic allocation for cpumask_var_t, instead of putting 550 them on the stack. This is a bit more expensive, but avoids 551 stack overflow. 552 553config FORCE_NR_CPUS 554 def_bool !SMP 555 556config CPU_RMAP 557 bool 558 depends on SMP 559 560config DQL 561 bool 562 563config GLOB 564 bool 565# This actually supports modular compilation, but the module overhead 566# is ridiculous for the amount of code involved. Until an out-of-tree 567# driver asks for it, we'll just link it directly it into the kernel 568# when required. Since we're ignoring out-of-tree users, there's also 569# no need bother prompting for a manual decision: 570# prompt "glob_match() function" 571 help 572 This option provides a glob_match function for performing 573 simple text pattern matching. It originated in the ATA code 574 to blacklist particular drive models, but other device drivers 575 may need similar functionality. 576 577 All drivers in the Linux kernel tree that require this function 578 should automatically select this option. Say N unless you 579 are compiling an out-of tree driver which tells you that it 580 depends on this. 581 582config GLOB_SELFTEST 583 tristate "glob self-test on init" 584 depends on GLOB 585 help 586 This option enables a simple self-test of the glob_match 587 function on startup. It is primarily useful for people 588 working on the code to ensure they haven't introduced any 589 regressions. 590 591 It only adds a little bit of code and slows kernel boot (or 592 module load) by a small amount, so you're welcome to play with 593 it, but you probably don't need it. 594 595# 596# Netlink attribute parsing support is select'ed if needed 597# 598config NLATTR 599 bool 600 601# 602# Generic 64-bit atomic support is selected if needed 603# 604config GENERIC_ATOMIC64 605 bool 606 607config LRU_CACHE 608 tristate 609 610config CLZ_TAB 611 bool 612 613config IRQ_POLL 614 bool "IRQ polling library" 615 help 616 Helper library to poll interrupt mitigation using polling. 617 618config MPILIB 619 tristate 620 select CLZ_TAB 621 help 622 Multiprecision maths library from GnuPG. 623 It is used to implement RSA digital signature verification, 624 which is used by IMA/EVM digital signature extension. 625 626config SIGNATURE 627 tristate 628 depends on KEYS 629 select CRYPTO 630 select CRYPTO_SHA1 631 select MPILIB 632 help 633 Digital signature verification. Currently only RSA is supported. 634 Implementation is done using GnuPG MPI library 635 636config DIMLIB 637 tristate 638 depends on NET 639 help 640 Dynamic Interrupt Moderation library. 641 Implements an algorithm for dynamically changing CQ moderation values 642 according to run time performance. 643 644# 645# libfdt files, only selected if needed. 646# 647config LIBFDT 648 bool 649 650config OID_REGISTRY 651 tristate 652 help 653 Enable fast lookup object identifier registry. 654 655config UCS2_STRING 656 tristate 657 658# 659# generic vdso 660# 661source "lib/vdso/Kconfig" 662 663source "lib/fonts/Kconfig" 664 665config SG_SPLIT 666 def_bool n 667 help 668 Provides a helper to split scatterlists into chunks, each chunk being 669 a scatterlist. This should be selected by a driver or an API which 670 whishes to split a scatterlist amongst multiple DMA channels. 671 672config SG_POOL 673 def_bool n 674 help 675 Provides a helper to allocate chained scatterlists. This should be 676 selected by a driver or an API which whishes to allocate chained 677 scatterlist. 678 679# 680# sg chaining option 681# 682 683config ARCH_NO_SG_CHAIN 684 def_bool n 685 686config ARCH_HAS_PMEM_API 687 bool 688 689config MEMREGION 690 bool 691 692config ARCH_HAS_CPU_CACHE_INVALIDATE_MEMREGION 693 bool 694 695config ARCH_HAS_MEMREMAP_COMPAT_ALIGN 696 bool 697 698# use memcpy to implement user copies for nommu architectures 699config UACCESS_MEMCPY 700 bool 701 702config ARCH_HAS_UACCESS_FLUSHCACHE 703 bool 704 705# arch has a concept of a recoverable synchronous exception due to a 706# memory-read error like x86 machine-check or ARM data-abort, and 707# implements copy_mc_to_{user,kernel} to abort and report 708# 'bytes-transferred' if that exception fires when accessing the source 709# buffer. 710config ARCH_HAS_COPY_MC 711 bool 712 713# Temporary. Goes away when all archs are cleaned up 714config ARCH_STACKWALK 715 bool 716 717config STACKDEPOT 718 bool 719 select STACKTRACE 720 help 721 Stack depot: stack trace storage that avoids duplication 722 723config STACKDEPOT_ALWAYS_INIT 724 bool 725 select STACKDEPOT 726 help 727 Always initialize stack depot during early boot 728 729config STACKDEPOT_MAX_FRAMES 730 int "Maximum number of frames in trace saved in stack depot" 731 range 1 256 732 default 64 733 depends on STACKDEPOT 734 735config REF_TRACKER 736 bool 737 depends on STACKTRACE_SUPPORT 738 select STACKDEPOT 739 740config SBITMAP 741 bool 742 743config PARMAN 744 tristate "parman" if COMPILE_TEST 745 746config OBJAGG 747 tristate "objagg" if COMPILE_TEST 748 749config LWQ_TEST 750 bool "Boot-time test for lwq queuing" 751 help 752 Run boot-time test of light-weight queuing. 753 754endmenu 755 756config GENERIC_IOREMAP 757 bool 758 759config GENERIC_LIB_ASHLDI3 760 bool 761 762config GENERIC_LIB_ASHRDI3 763 bool 764 765config GENERIC_LIB_LSHRDI3 766 bool 767 768config GENERIC_LIB_MULDI3 769 bool 770 771config GENERIC_LIB_CMPDI2 772 bool 773 774config GENERIC_LIB_UCMPDI2 775 bool 776 777config GENERIC_LIB_DEVMEM_IS_ALLOWED 778 bool 779 780config PLDMFW 781 bool 782 default n 783 784config ASN1_ENCODER 785 tristate 786 787config POLYNOMIAL 788 tristate 789 790config FIRMWARE_TABLE 791 bool 792 793config UNION_FIND 794 bool 795 796config MIN_HEAP 797 bool 798