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 67config GENERIC_FIND_FIRST_BIT 68 bool 69 70source "lib/math/Kconfig" 71 72config NO_GENERIC_PCI_IOPORT_MAP 73 bool 74 75config GENERIC_PCI_IOMAP 76 bool 77 78config GENERIC_IOMAP 79 bool 80 select GENERIC_PCI_IOMAP 81 82config STMP_DEVICE 83 bool 84 85config ARCH_USE_CMPXCHG_LOCKREF 86 bool 87 88config ARCH_HAS_FAST_MULTIPLIER 89 bool 90 91config ARCH_USE_SYM_ANNOTATIONS 92 bool 93 94config INDIRECT_PIO 95 bool "Access I/O in non-MMIO mode" 96 depends on ARM64 97 help 98 On some platforms where no separate I/O space exists, there are I/O 99 hosts which can not be accessed in MMIO mode. Using the logical PIO 100 mechanism, the host-local I/O resource can be mapped into system 101 logic PIO space shared with MMIO hosts, such as PCI/PCIe, then the 102 system can access the I/O devices with the mapped-logic PIO through 103 I/O accessors. 104 105 This way has relatively little I/O performance cost. Please make 106 sure your devices really need this configure item enabled. 107 108 When in doubt, say N. 109 110config INDIRECT_IOMEM 111 bool 112 help 113 This is selected by other options/architectures to provide the 114 emulated iomem accessors. 115 116config INDIRECT_IOMEM_FALLBACK 117 bool 118 depends on INDIRECT_IOMEM 119 help 120 If INDIRECT_IOMEM is selected, this enables falling back to plain 121 mmio accesses when the IO memory address is not a registered 122 emulated region. 123 124source "lib/crypto/Kconfig" 125 126config LIB_MEMNEQ 127 bool 128 129config TRACE_MMIO_ACCESS 130 bool "Register read/write tracing" 131 depends on TRACING && ARCH_HAVE_TRACE_MMIO_ACCESS 132 help 133 Create tracepoints for MMIO read/write operations. These trace events 134 can be used for logging all MMIO read/write operations. 135 136config CRC_CCITT 137 tristate "CRC-CCITT functions" 138 help 139 This option is provided for the case where no in-kernel-tree 140 modules require CRC-CCITT functions, but a module built outside 141 the kernel tree does. Such modules that use library CRC-CCITT 142 functions require M here. 143 144config CRC16 145 tristate "CRC16 functions" 146 help 147 This option is provided for the case where no in-kernel-tree 148 modules require CRC16 functions, but a module built outside 149 the kernel tree does. Such modules that use library CRC16 150 functions require M here. 151 152config CRC_T10DIF 153 tristate "CRC calculation for the T10 Data Integrity Field" 154 select CRYPTO 155 select CRYPTO_CRCT10DIF 156 help 157 This option is only needed if a module that's not in the 158 kernel tree needs to calculate CRC checks for use with the 159 SCSI data integrity subsystem. 160 161config CRC_ITU_T 162 tristate "CRC ITU-T V.41 functions" 163 help 164 This option is provided for the case where no in-kernel-tree 165 modules require CRC ITU-T V.41 functions, but a module built outside 166 the kernel tree does. Such modules that use library CRC ITU-T V.41 167 functions require M here. 168 169config CRC32 170 tristate "CRC32/CRC32c functions" 171 default y 172 select BITREVERSE 173 help 174 This option is provided for the case where no in-kernel-tree 175 modules require CRC32/CRC32c functions, but a module built outside 176 the kernel tree does. Such modules that use library CRC32/CRC32c 177 functions require M here. 178 179config CRC32_SELFTEST 180 tristate "CRC32 perform self test on init" 181 depends on CRC32 182 help 183 This option enables the CRC32 library functions to perform a 184 self test on initialization. The self test computes crc32_le 185 and crc32_be over byte strings with random alignment and length 186 and computes the total elapsed time and number of bytes processed. 187 188choice 189 prompt "CRC32 implementation" 190 depends on CRC32 191 default CRC32_SLICEBY8 192 help 193 This option allows a kernel builder to override the default choice 194 of CRC32 algorithm. Choose the default ("slice by 8") unless you 195 know that you need one of the others. 196 197config CRC32_SLICEBY8 198 bool "Slice by 8 bytes" 199 help 200 Calculate checksum 8 bytes at a time with a clever slicing algorithm. 201 This is the fastest algorithm, but comes with a 8KiB lookup table. 202 Most modern processors have enough cache to hold this table without 203 thrashing the cache. 204 205 This is the default implementation choice. Choose this one unless 206 you have a good reason not to. 207 208config CRC32_SLICEBY4 209 bool "Slice by 4 bytes" 210 help 211 Calculate checksum 4 bytes at a time with a clever slicing algorithm. 212 This is a bit slower than slice by 8, but has a smaller 4KiB lookup 213 table. 214 215 Only choose this option if you know what you are doing. 216 217config CRC32_SARWATE 218 bool "Sarwate's Algorithm (one byte at a time)" 219 help 220 Calculate checksum a byte at a time using Sarwate's algorithm. This 221 is not particularly fast, but has a small 256 byte lookup table. 222 223 Only choose this option if you know what you are doing. 224 225config CRC32_BIT 226 bool "Classic Algorithm (one bit at a time)" 227 help 228 Calculate checksum one bit at a time. This is VERY slow, but has 229 no lookup table. This is provided as a debugging option. 230 231 Only choose this option if you are debugging crc32. 232 233endchoice 234 235config CRC64 236 tristate "CRC64 functions" 237 help 238 This option is provided for the case where no in-kernel-tree 239 modules require CRC64 functions, but a module built outside 240 the kernel tree does. Such modules that use library CRC64 241 functions require M here. 242 243config CRC4 244 tristate "CRC4 functions" 245 help 246 This option is provided for the case where no in-kernel-tree 247 modules require CRC4 functions, but a module built outside 248 the kernel tree does. Such modules that use library CRC4 249 functions require M here. 250 251config CRC7 252 tristate "CRC7 functions" 253 help 254 This option is provided for the case where no in-kernel-tree 255 modules require CRC7 functions, but a module built outside 256 the kernel tree does. Such modules that use library CRC7 257 functions require M here. 258 259config LIBCRC32C 260 tristate "CRC32c (Castagnoli, et al) Cyclic Redundancy-Check" 261 select CRYPTO 262 select CRYPTO_CRC32C 263 help 264 This option is provided for the case where no in-kernel-tree 265 modules require CRC32c functions, but a module built outside the 266 kernel tree does. Such modules that use library CRC32c functions 267 require M here. See Castagnoli93. 268 Module will be libcrc32c. 269 270config CRC8 271 tristate "CRC8 function" 272 help 273 This option provides CRC8 function. Drivers may select this 274 when they need to do cyclic redundancy check according CRC8 275 algorithm. Module will be called crc8. 276 277config XXHASH 278 tristate 279 280config AUDIT_GENERIC 281 bool 282 depends on AUDIT && !AUDIT_ARCH 283 default y 284 285config AUDIT_ARCH_COMPAT_GENERIC 286 bool 287 default n 288 289config AUDIT_COMPAT_GENERIC 290 bool 291 depends on AUDIT_GENERIC && AUDIT_ARCH_COMPAT_GENERIC && COMPAT 292 default y 293 294config RANDOM32_SELFTEST 295 bool "PRNG perform self test on init" 296 help 297 This option enables the 32 bit PRNG library functions to perform a 298 self test on initialization. 299 300# 301# compression support is select'ed if needed 302# 303config 842_COMPRESS 304 select CRC32 305 tristate 306 307config 842_DECOMPRESS 308 select CRC32 309 tristate 310 311config ZLIB_INFLATE 312 tristate 313 314config ZLIB_DEFLATE 315 tristate 316 select BITREVERSE 317 318config ZLIB_DFLTCC 319 def_bool y 320 depends on S390 321 prompt "Enable s390x DEFLATE CONVERSION CALL support for kernel zlib" 322 help 323 Enable s390x hardware support for zlib in the kernel. 324 325config LZO_COMPRESS 326 tristate 327 328config LZO_DECOMPRESS 329 tristate 330 331config LZ4_COMPRESS 332 tristate 333 334config LZ4HC_COMPRESS 335 tristate 336 337config LZ4_DECOMPRESS 338 tristate 339 340config ZSTD_COMPRESS 341 select XXHASH 342 tristate 343 344config ZSTD_DECOMPRESS 345 select XXHASH 346 tristate 347 348source "lib/xz/Kconfig" 349 350# 351# These all provide a common interface (hence the apparent duplication with 352# ZLIB_INFLATE; DECOMPRESS_GZIP is just a wrapper.) 353# 354config DECOMPRESS_GZIP 355 select ZLIB_INFLATE 356 tristate 357 358config DECOMPRESS_BZIP2 359 tristate 360 361config DECOMPRESS_LZMA 362 tristate 363 364config DECOMPRESS_XZ 365 select XZ_DEC 366 tristate 367 368config DECOMPRESS_LZO 369 select LZO_DECOMPRESS 370 tristate 371 372config DECOMPRESS_LZ4 373 select LZ4_DECOMPRESS 374 tristate 375 376config DECOMPRESS_ZSTD 377 select ZSTD_DECOMPRESS 378 tristate 379 380# 381# Generic allocator support is selected if needed 382# 383config GENERIC_ALLOCATOR 384 bool 385 386# 387# reed solomon support is select'ed if needed 388# 389config REED_SOLOMON 390 tristate 391 392config REED_SOLOMON_ENC8 393 bool 394 395config REED_SOLOMON_DEC8 396 bool 397 398config REED_SOLOMON_ENC16 399 bool 400 401config REED_SOLOMON_DEC16 402 bool 403 404# 405# BCH support is selected if needed 406# 407config BCH 408 tristate 409 410config BCH_CONST_PARAMS 411 bool 412 help 413 Drivers may select this option to force specific constant 414 values for parameters 'm' (Galois field order) and 't' 415 (error correction capability). Those specific values must 416 be set by declaring default values for symbols BCH_CONST_M 417 and BCH_CONST_T. 418 Doing so will enable extra compiler optimizations, 419 improving encoding and decoding performance up to 2x for 420 usual (m,t) values (typically such that m*t < 200). 421 When this option is selected, the BCH library supports 422 only a single (m,t) configuration. This is mainly useful 423 for NAND flash board drivers requiring known, fixed BCH 424 parameters. 425 426config BCH_CONST_M 427 int 428 range 5 15 429 help 430 Constant value for Galois field order 'm'. If 'k' is the 431 number of data bits to protect, 'm' should be chosen such 432 that (k + m*t) <= 2**m - 1. 433 Drivers should declare a default value for this symbol if 434 they select option BCH_CONST_PARAMS. 435 436config BCH_CONST_T 437 int 438 help 439 Constant value for error correction capability in bits 't'. 440 Drivers should declare a default value for this symbol if 441 they select option BCH_CONST_PARAMS. 442 443# 444# Textsearch support is select'ed if needed 445# 446config TEXTSEARCH 447 bool 448 449config TEXTSEARCH_KMP 450 tristate 451 452config TEXTSEARCH_BM 453 tristate 454 455config TEXTSEARCH_FSM 456 tristate 457 458config BTREE 459 bool 460 461config INTERVAL_TREE 462 bool 463 help 464 Simple, embeddable, interval-tree. Can find the start of an 465 overlapping range in log(n) time and then iterate over all 466 overlapping nodes. The algorithm is implemented as an 467 augmented rbtree. 468 469 See: 470 471 Documentation/core-api/rbtree.rst 472 473 for more information. 474 475config XARRAY_MULTI 476 bool 477 help 478 Support entries which occupy multiple consecutive indices in the 479 XArray. 480 481config ASSOCIATIVE_ARRAY 482 bool 483 help 484 Generic associative array. Can be searched and iterated over whilst 485 it is being modified. It is also reasonably quick to search and 486 modify. The algorithms are non-recursive, and the trees are highly 487 capacious. 488 489 See: 490 491 Documentation/core-api/assoc_array.rst 492 493 for more information. 494 495config HAS_IOMEM 496 bool 497 depends on !NO_IOMEM 498 default y 499 500config HAS_IOPORT_MAP 501 bool 502 depends on HAS_IOMEM && !NO_IOPORT_MAP 503 default y 504 505source "kernel/dma/Kconfig" 506 507config SGL_ALLOC 508 bool 509 default n 510 511config IOMMU_HELPER 512 bool 513 514config CHECK_SIGNATURE 515 bool 516 517config CPUMASK_OFFSTACK 518 bool "Force CPU masks off stack" if DEBUG_PER_CPU_MAPS 519 help 520 Use dynamic allocation for cpumask_var_t, instead of putting 521 them on the stack. This is a bit more expensive, but avoids 522 stack overflow. 523 524config CPU_RMAP 525 bool 526 depends on SMP 527 528config DQL 529 bool 530 531config GLOB 532 bool 533# This actually supports modular compilation, but the module overhead 534# is ridiculous for the amount of code involved. Until an out-of-tree 535# driver asks for it, we'll just link it directly it into the kernel 536# when required. Since we're ignoring out-of-tree users, there's also 537# no need bother prompting for a manual decision: 538# prompt "glob_match() function" 539 help 540 This option provides a glob_match function for performing 541 simple text pattern matching. It originated in the ATA code 542 to blacklist particular drive models, but other device drivers 543 may need similar functionality. 544 545 All drivers in the Linux kernel tree that require this function 546 should automatically select this option. Say N unless you 547 are compiling an out-of tree driver which tells you that it 548 depends on this. 549 550config GLOB_SELFTEST 551 tristate "glob self-test on init" 552 depends on GLOB 553 help 554 This option enables a simple self-test of the glob_match 555 function on startup. It is primarily useful for people 556 working on the code to ensure they haven't introduced any 557 regressions. 558 559 It only adds a little bit of code and slows kernel boot (or 560 module load) by a small amount, so you're welcome to play with 561 it, but you probably don't need it. 562 563# 564# Netlink attribute parsing support is select'ed if needed 565# 566config NLATTR 567 bool 568 569# 570# Generic 64-bit atomic support is selected if needed 571# 572config GENERIC_ATOMIC64 573 bool 574 575config LRU_CACHE 576 tristate 577 578config CLZ_TAB 579 bool 580 581config IRQ_POLL 582 bool "IRQ polling library" 583 help 584 Helper library to poll interrupt mitigation using polling. 585 586config MPILIB 587 tristate 588 select CLZ_TAB 589 help 590 Multiprecision maths library from GnuPG. 591 It is used to implement RSA digital signature verification, 592 which is used by IMA/EVM digital signature extension. 593 594config SIGNATURE 595 tristate 596 depends on KEYS 597 select CRYPTO 598 select CRYPTO_SHA1 599 select MPILIB 600 help 601 Digital signature verification. Currently only RSA is supported. 602 Implementation is done using GnuPG MPI library 603 604config DIMLIB 605 bool 606 help 607 Dynamic Interrupt Moderation library. 608 Implements an algorithm for dynamically changing CQ moderation values 609 according to run time performance. 610 611# 612# libfdt files, only selected if needed. 613# 614config LIBFDT 615 bool 616 617config OID_REGISTRY 618 tristate 619 help 620 Enable fast lookup object identifier registry. 621 622config UCS2_STRING 623 tristate 624 625# 626# generic vdso 627# 628source "lib/vdso/Kconfig" 629 630source "lib/fonts/Kconfig" 631 632config SG_SPLIT 633 def_bool n 634 help 635 Provides a helper to split scatterlists into chunks, each chunk being 636 a scatterlist. This should be selected by a driver or an API which 637 whishes to split a scatterlist amongst multiple DMA channels. 638 639config SG_POOL 640 def_bool n 641 help 642 Provides a helper to allocate chained scatterlists. This should be 643 selected by a driver or an API which whishes to allocate chained 644 scatterlist. 645 646# 647# sg chaining option 648# 649 650config ARCH_NO_SG_CHAIN 651 def_bool n 652 653config ARCH_HAS_PMEM_API 654 bool 655 656config MEMREGION 657 bool 658 659config ARCH_HAS_MEMREMAP_COMPAT_ALIGN 660 bool 661 662# use memcpy to implement user copies for nommu architectures 663config UACCESS_MEMCPY 664 bool 665 666config ARCH_HAS_UACCESS_FLUSHCACHE 667 bool 668 669# arch has a concept of a recoverable synchronous exception due to a 670# memory-read error like x86 machine-check or ARM data-abort, and 671# implements copy_mc_to_{user,kernel} to abort and report 672# 'bytes-transferred' if that exception fires when accessing the source 673# buffer. 674config ARCH_HAS_COPY_MC 675 bool 676 677# Temporary. Goes away when all archs are cleaned up 678config ARCH_STACKWALK 679 bool 680 681config STACKDEPOT 682 bool 683 select STACKTRACE 684 685config STACK_HASH_ORDER 686 int "stack depot hash size (12 => 4KB, 20 => 1024KB)" 687 range 12 20 688 default 20 689 depends on STACKDEPOT 690 help 691 Select the hash size as a power of 2 for the stackdepot hash table. 692 Choose a lower value to reduce the memory impact. 693 694config SBITMAP 695 bool 696 697config PARMAN 698 tristate "parman" if COMPILE_TEST 699 700config OBJAGG 701 tristate "objagg" if COMPILE_TEST 702 703endmenu 704 705config GENERIC_IOREMAP 706 bool 707 708config GENERIC_LIB_ASHLDI3 709 bool 710 711config GENERIC_LIB_ASHRDI3 712 bool 713 714config GENERIC_LIB_LSHRDI3 715 bool 716 717config GENERIC_LIB_MULDI3 718 bool 719 720config GENERIC_LIB_CMPDI2 721 bool 722 723config GENERIC_LIB_UCMPDI2 724 bool 725 726config GENERIC_LIB_DEVMEM_IS_ALLOWED 727 bool 728 729config PLDMFW 730 bool 731 default n 732 733config ASN1_ENCODER 734 tristate 735