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 help 160 This option is only needed if a module that's not in the 161 kernel tree needs to calculate CRC checks for use with the 162 SCSI data integrity subsystem. 163 164config ARCH_HAS_CRC_T10DIF 165 bool 166 167choice 168 prompt "CRC-T10DIF implementation" 169 depends on CRC_T10DIF 170 default CRC_T10DIF_IMPL_ARCH if ARCH_HAS_CRC_T10DIF 171 default CRC_T10DIF_IMPL_GENERIC if !ARCH_HAS_CRC_T10DIF 172 help 173 This option allows you to override the default choice of CRC-T10DIF 174 implementation. 175 176config CRC_T10DIF_IMPL_ARCH 177 bool "Architecture-optimized" if ARCH_HAS_CRC_T10DIF 178 help 179 Use the optimized implementation of CRC-T10DIF for the selected 180 architecture. It is recommended to keep this enabled, as it can 181 greatly improve CRC-T10DIF performance. 182 183config CRC_T10DIF_IMPL_GENERIC 184 bool "Generic implementation" 185 help 186 Use the generic table-based implementation of CRC-T10DIF. Selecting 187 this will reduce code size slightly but can greatly reduce CRC-T10DIF 188 performance. 189 190endchoice 191 192config CRC_T10DIF_ARCH 193 tristate 194 default CRC_T10DIF if CRC_T10DIF_IMPL_ARCH 195 196config CRC64_ROCKSOFT 197 tristate "CRC calculation for the Rocksoft model CRC64" 198 select CRC64 199 select CRYPTO 200 select CRYPTO_CRC64_ROCKSOFT 201 help 202 This option provides a CRC64 API to a registered crypto driver. 203 This is used with the block layer's data integrity subsystem. 204 205config CRC_ITU_T 206 tristate "CRC ITU-T V.41 functions" 207 help 208 This option is provided for the case where no in-kernel-tree 209 modules require CRC ITU-T V.41 functions, but a module built outside 210 the kernel tree does. Such modules that use library CRC ITU-T V.41 211 functions require M here. 212 213config CRC32 214 tristate "CRC32/CRC32c functions" 215 default y 216 select BITREVERSE 217 help 218 This option is provided for the case where no in-kernel-tree 219 modules require CRC32/CRC32c functions, but a module built outside 220 the kernel tree does. Such modules that use library CRC32/CRC32c 221 functions require M here. 222 223config ARCH_HAS_CRC32 224 bool 225 226choice 227 prompt "CRC32 implementation" 228 depends on CRC32 229 default CRC32_IMPL_ARCH_PLUS_SLICEBY8 if ARCH_HAS_CRC32 230 default CRC32_IMPL_SLICEBY8 if !ARCH_HAS_CRC32 231 help 232 This option allows you to override the default choice of CRC32 233 implementation. Choose the default unless you know that you need one 234 of the others. 235 236config CRC32_IMPL_ARCH_PLUS_SLICEBY8 237 bool "Arch-optimized, with fallback to slice-by-8" if ARCH_HAS_CRC32 238 help 239 Use architecture-optimized implementation of CRC32. Fall back to 240 slice-by-8 in cases where the arch-optimized implementation cannot be 241 used, e.g. if the CPU lacks support for the needed instructions. 242 243 This is the default when an arch-optimized implementation exists. 244 245config CRC32_IMPL_ARCH_PLUS_SLICEBY1 246 bool "Arch-optimized, with fallback to slice-by-1" if ARCH_HAS_CRC32 247 help 248 Use architecture-optimized implementation of CRC32, but fall back to 249 slice-by-1 instead of slice-by-8 in order to reduce the binary size. 250 251config CRC32_IMPL_SLICEBY8 252 bool "Slice by 8 bytes" 253 help 254 Calculate checksum 8 bytes at a time with a clever slicing algorithm. 255 This is much slower than the architecture-optimized implementation of 256 CRC32 (if the selected arch has one), but it is portable and is the 257 fastest implementation when no arch-optimized implementation is 258 available. It uses an 8KiB lookup table. Most modern processors have 259 enough cache to hold this table without thrashing the cache. 260 261config CRC32_IMPL_SLICEBY4 262 bool "Slice by 4 bytes" 263 help 264 Calculate checksum 4 bytes at a time with a clever slicing algorithm. 265 This is a bit slower than slice by 8, but has a smaller 4KiB lookup 266 table. 267 268 Only choose this option if you know what you are doing. 269 270config CRC32_IMPL_SLICEBY1 271 bool "Slice by 1 byte (Sarwate's algorithm)" 272 help 273 Calculate checksum a byte at a time using Sarwate's algorithm. This 274 is not particularly fast, but has a small 1KiB lookup table. 275 276 Only choose this option if you know what you are doing. 277 278config CRC32_IMPL_BIT 279 bool "Classic Algorithm (one bit at a time)" 280 help 281 Calculate checksum one bit at a time. This is VERY slow, but has 282 no lookup table. This is provided as a debugging option. 283 284 Only choose this option if you are debugging crc32. 285 286endchoice 287 288config CRC32_ARCH 289 tristate 290 default CRC32 if CRC32_IMPL_ARCH_PLUS_SLICEBY8 || CRC32_IMPL_ARCH_PLUS_SLICEBY1 291 292config CRC32_SLICEBY8 293 bool 294 default y if CRC32_IMPL_SLICEBY8 || CRC32_IMPL_ARCH_PLUS_SLICEBY8 295 296config CRC32_SLICEBY4 297 bool 298 default y if CRC32_IMPL_SLICEBY4 299 300config CRC32_SARWATE 301 bool 302 default y if CRC32_IMPL_SLICEBY1 || CRC32_IMPL_ARCH_PLUS_SLICEBY1 303 304config CRC32_BIT 305 bool 306 default y if CRC32_IMPL_BIT 307 308config CRC64 309 tristate "CRC64 functions" 310 help 311 This option is provided for the case where no in-kernel-tree 312 modules require CRC64 functions, but a module built outside 313 the kernel tree does. Such modules that use library CRC64 314 functions require M here. 315 316config CRC4 317 tristate "CRC4 functions" 318 help 319 This option is provided for the case where no in-kernel-tree 320 modules require CRC4 functions, but a module built outside 321 the kernel tree does. Such modules that use library CRC4 322 functions require M here. 323 324config CRC7 325 tristate "CRC7 functions" 326 help 327 This option is provided for the case where no in-kernel-tree 328 modules require CRC7 functions, but a module built outside 329 the kernel tree does. Such modules that use library CRC7 330 functions require M here. 331 332config LIBCRC32C 333 tristate "CRC32c (Castagnoli, et al) Cyclic Redundancy-Check" 334 select CRC32 335 help 336 This option just selects CRC32 and is provided for compatibility 337 purposes until the users are updated to select CRC32 directly. 338 339config CRC8 340 tristate "CRC8 function" 341 help 342 This option provides CRC8 function. Drivers may select this 343 when they need to do cyclic redundancy check according CRC8 344 algorithm. Module will be called crc8. 345 346config XXHASH 347 tristate 348 349config AUDIT_GENERIC 350 bool 351 depends on AUDIT && !AUDIT_ARCH 352 default y 353 354config AUDIT_ARCH_COMPAT_GENERIC 355 bool 356 default n 357 358config AUDIT_COMPAT_GENERIC 359 bool 360 depends on AUDIT_GENERIC && AUDIT_ARCH_COMPAT_GENERIC && COMPAT 361 default y 362 363config RANDOM32_SELFTEST 364 bool "PRNG perform self test on init" 365 help 366 This option enables the 32 bit PRNG library functions to perform a 367 self test on initialization. 368 369# 370# compression support is select'ed if needed 371# 372config 842_COMPRESS 373 select CRC32 374 tristate 375 376config 842_DECOMPRESS 377 select CRC32 378 tristate 379 380config ZLIB_INFLATE 381 tristate 382 383config ZLIB_DEFLATE 384 tristate 385 select BITREVERSE 386 387config ZLIB_DFLTCC 388 def_bool y 389 depends on S390 390 prompt "Enable s390x DEFLATE CONVERSION CALL support for kernel zlib" 391 help 392 Enable s390x hardware support for zlib in the kernel. 393 394config LZO_COMPRESS 395 tristate 396 397config LZO_DECOMPRESS 398 tristate 399 400config LZ4_COMPRESS 401 tristate 402 403config LZ4HC_COMPRESS 404 tristate 405 406config LZ4_DECOMPRESS 407 tristate 408 409config ZSTD_COMMON 410 select XXHASH 411 tristate 412 413config ZSTD_COMPRESS 414 select ZSTD_COMMON 415 tristate 416 417config ZSTD_DECOMPRESS 418 select ZSTD_COMMON 419 tristate 420 421source "lib/xz/Kconfig" 422 423# 424# These all provide a common interface (hence the apparent duplication with 425# ZLIB_INFLATE; DECOMPRESS_GZIP is just a wrapper.) 426# 427config DECOMPRESS_GZIP 428 select ZLIB_INFLATE 429 tristate 430 431config DECOMPRESS_BZIP2 432 tristate 433 434config DECOMPRESS_LZMA 435 tristate 436 437config DECOMPRESS_XZ 438 select XZ_DEC 439 tristate 440 441config DECOMPRESS_LZO 442 select LZO_DECOMPRESS 443 tristate 444 445config DECOMPRESS_LZ4 446 select LZ4_DECOMPRESS 447 tristate 448 449config DECOMPRESS_ZSTD 450 select ZSTD_DECOMPRESS 451 tristate 452 453# 454# Generic allocator support is selected if needed 455# 456config GENERIC_ALLOCATOR 457 bool 458 459# 460# reed solomon support is select'ed if needed 461# 462config REED_SOLOMON 463 tristate 464 465config REED_SOLOMON_ENC8 466 bool 467 468config REED_SOLOMON_DEC8 469 bool 470 471config REED_SOLOMON_ENC16 472 bool 473 474config REED_SOLOMON_DEC16 475 bool 476 477# 478# BCH support is selected if needed 479# 480config BCH 481 tristate 482 select BITREVERSE 483 484config BCH_CONST_PARAMS 485 bool 486 help 487 Drivers may select this option to force specific constant 488 values for parameters 'm' (Galois field order) and 't' 489 (error correction capability). Those specific values must 490 be set by declaring default values for symbols BCH_CONST_M 491 and BCH_CONST_T. 492 Doing so will enable extra compiler optimizations, 493 improving encoding and decoding performance up to 2x for 494 usual (m,t) values (typically such that m*t < 200). 495 When this option is selected, the BCH library supports 496 only a single (m,t) configuration. This is mainly useful 497 for NAND flash board drivers requiring known, fixed BCH 498 parameters. 499 500config BCH_CONST_M 501 int 502 range 5 15 503 help 504 Constant value for Galois field order 'm'. If 'k' is the 505 number of data bits to protect, 'm' should be chosen such 506 that (k + m*t) <= 2**m - 1. 507 Drivers should declare a default value for this symbol if 508 they select option BCH_CONST_PARAMS. 509 510config BCH_CONST_T 511 int 512 help 513 Constant value for error correction capability in bits 't'. 514 Drivers should declare a default value for this symbol if 515 they select option BCH_CONST_PARAMS. 516 517# 518# Textsearch support is select'ed if needed 519# 520config TEXTSEARCH 521 bool 522 523config TEXTSEARCH_KMP 524 tristate 525 526config TEXTSEARCH_BM 527 tristate 528 529config TEXTSEARCH_FSM 530 tristate 531 532config BTREE 533 bool 534 535config INTERVAL_TREE 536 bool 537 help 538 Simple, embeddable, interval-tree. Can find the start of an 539 overlapping range in log(n) time and then iterate over all 540 overlapping nodes. The algorithm is implemented as an 541 augmented rbtree. 542 543 See: 544 545 Documentation/core-api/rbtree.rst 546 547 for more information. 548 549config INTERVAL_TREE_SPAN_ITER 550 bool 551 depends on INTERVAL_TREE 552 553config XARRAY_MULTI 554 bool 555 help 556 Support entries which occupy multiple consecutive indices in the 557 XArray. 558 559config ASSOCIATIVE_ARRAY 560 bool 561 help 562 Generic associative array. Can be searched and iterated over whilst 563 it is being modified. It is also reasonably quick to search and 564 modify. The algorithms are non-recursive, and the trees are highly 565 capacious. 566 567 See: 568 569 Documentation/core-api/assoc_array.rst 570 571 for more information. 572 573config CLOSURES 574 bool 575 576config HAS_IOMEM 577 bool 578 depends on !NO_IOMEM 579 default y 580 581config HAS_IOPORT 582 bool 583 584config HAS_IOPORT_MAP 585 bool 586 depends on HAS_IOMEM && !NO_IOPORT_MAP 587 default y 588 589source "kernel/dma/Kconfig" 590 591config SGL_ALLOC 592 bool 593 default n 594 595config IOMMU_HELPER 596 bool 597 598config CHECK_SIGNATURE 599 bool 600 601config CPUMASK_OFFSTACK 602 bool "Force CPU masks off stack" if DEBUG_PER_CPU_MAPS 603 help 604 Use dynamic allocation for cpumask_var_t, instead of putting 605 them on the stack. This is a bit more expensive, but avoids 606 stack overflow. 607 608config FORCE_NR_CPUS 609 def_bool !SMP 610 611config CPU_RMAP 612 bool 613 depends on SMP 614 615config DQL 616 bool 617 618config GLOB 619 bool 620# This actually supports modular compilation, but the module overhead 621# is ridiculous for the amount of code involved. Until an out-of-tree 622# driver asks for it, we'll just link it directly it into the kernel 623# when required. Since we're ignoring out-of-tree users, there's also 624# no need bother prompting for a manual decision: 625# prompt "glob_match() function" 626 help 627 This option provides a glob_match function for performing 628 simple text pattern matching. It originated in the ATA code 629 to blacklist particular drive models, but other device drivers 630 may need similar functionality. 631 632 All drivers in the Linux kernel tree that require this function 633 should automatically select this option. Say N unless you 634 are compiling an out-of tree driver which tells you that it 635 depends on this. 636 637config GLOB_SELFTEST 638 tristate "glob self-test on init" 639 depends on GLOB 640 help 641 This option enables a simple self-test of the glob_match 642 function on startup. It is primarily useful for people 643 working on the code to ensure they haven't introduced any 644 regressions. 645 646 It only adds a little bit of code and slows kernel boot (or 647 module load) by a small amount, so you're welcome to play with 648 it, but you probably don't need it. 649 650# 651# Netlink attribute parsing support is select'ed if needed 652# 653config NLATTR 654 bool 655 656# 657# Generic 64-bit atomic support is selected if needed 658# 659config GENERIC_ATOMIC64 660 bool 661 662config LRU_CACHE 663 tristate 664 665config CLZ_TAB 666 bool 667 668config IRQ_POLL 669 bool "IRQ polling library" 670 help 671 Helper library to poll interrupt mitigation using polling. 672 673config MPILIB 674 tristate 675 select CLZ_TAB 676 help 677 Multiprecision maths library from GnuPG. 678 It is used to implement RSA digital signature verification, 679 which is used by IMA/EVM digital signature extension. 680 681config SIGNATURE 682 tristate 683 depends on KEYS 684 select CRYPTO 685 select CRYPTO_SHA1 686 select MPILIB 687 help 688 Digital signature verification. Currently only RSA is supported. 689 Implementation is done using GnuPG MPI library 690 691config DIMLIB 692 tristate 693 depends on NET 694 help 695 Dynamic Interrupt Moderation library. 696 Implements an algorithm for dynamically changing CQ moderation values 697 according to run time performance. 698 699# 700# libfdt files, only selected if needed. 701# 702config LIBFDT 703 bool 704 705config OID_REGISTRY 706 tristate 707 help 708 Enable fast lookup object identifier registry. 709 710config UCS2_STRING 711 tristate 712 713# 714# generic vdso 715# 716source "lib/vdso/Kconfig" 717 718source "lib/fonts/Kconfig" 719 720config SG_SPLIT 721 def_bool n 722 help 723 Provides a helper to split scatterlists into chunks, each chunk being 724 a scatterlist. This should be selected by a driver or an API which 725 whishes to split a scatterlist amongst multiple DMA channels. 726 727config SG_POOL 728 def_bool n 729 help 730 Provides a helper to allocate chained scatterlists. This should be 731 selected by a driver or an API which whishes to allocate chained 732 scatterlist. 733 734# 735# sg chaining option 736# 737 738config ARCH_NO_SG_CHAIN 739 def_bool n 740 741config ARCH_HAS_PMEM_API 742 bool 743 744config MEMREGION 745 bool 746 747config ARCH_HAS_CPU_CACHE_INVALIDATE_MEMREGION 748 bool 749 750config ARCH_HAS_MEMREMAP_COMPAT_ALIGN 751 bool 752 753# use memcpy to implement user copies for nommu architectures 754config UACCESS_MEMCPY 755 bool 756 757config ARCH_HAS_UACCESS_FLUSHCACHE 758 bool 759 760# arch has a concept of a recoverable synchronous exception due to a 761# memory-read error like x86 machine-check or ARM data-abort, and 762# implements copy_mc_to_{user,kernel} to abort and report 763# 'bytes-transferred' if that exception fires when accessing the source 764# buffer. 765config ARCH_HAS_COPY_MC 766 bool 767 768# Temporary. Goes away when all archs are cleaned up 769config ARCH_STACKWALK 770 bool 771 772config STACKDEPOT 773 bool 774 select STACKTRACE 775 help 776 Stack depot: stack trace storage that avoids duplication 777 778config STACKDEPOT_ALWAYS_INIT 779 bool 780 select STACKDEPOT 781 help 782 Always initialize stack depot during early boot 783 784config STACKDEPOT_MAX_FRAMES 785 int "Maximum number of frames in trace saved in stack depot" 786 range 1 256 787 default 64 788 depends on STACKDEPOT 789 790config REF_TRACKER 791 bool 792 depends on STACKTRACE_SUPPORT 793 select STACKDEPOT 794 795config SBITMAP 796 bool 797 798config PARMAN 799 tristate "parman" if COMPILE_TEST 800 801config OBJAGG 802 tristate "objagg" if COMPILE_TEST 803 804config LWQ_TEST 805 bool "Boot-time test for lwq queuing" 806 help 807 Run boot-time test of light-weight queuing. 808 809endmenu 810 811config GENERIC_IOREMAP 812 bool 813 814config GENERIC_LIB_ASHLDI3 815 bool 816 817config GENERIC_LIB_ASHRDI3 818 bool 819 820config GENERIC_LIB_LSHRDI3 821 bool 822 823config GENERIC_LIB_MULDI3 824 bool 825 826config GENERIC_LIB_CMPDI2 827 bool 828 829config GENERIC_LIB_UCMPDI2 830 bool 831 832config GENERIC_LIB_DEVMEM_IS_ALLOWED 833 bool 834 835config PLDMFW 836 bool 837 default n 838 839config ASN1_ENCODER 840 tristate 841 842config POLYNOMIAL 843 tristate 844 845config FIRMWARE_TABLE 846 bool 847 848config UNION_FIND 849 bool 850 851config MIN_HEAP 852 bool 853