1# 2# Library configuration 3# 4 5config BINARY_PRINTF 6 def_bool n 7 8menu "Library routines" 9 10config RAID6_PQ 11 tristate 12 13config BITREVERSE 14 tristate 15 16config HAVE_ARCH_BITREVERSE 17 bool 18 default n 19 depends on BITREVERSE 20 help 21 This option enables the use of hardware bit-reversal instructions on 22 architectures which support such operations. 23 24config RATIONAL 25 bool 26 27config GENERIC_STRNCPY_FROM_USER 28 bool 29 30config GENERIC_STRNLEN_USER 31 bool 32 33config GENERIC_NET_UTILS 34 bool 35 36config GENERIC_FIND_FIRST_BIT 37 bool 38 39config NO_GENERIC_PCI_IOPORT_MAP 40 bool 41 42config GENERIC_PCI_IOMAP 43 bool 44 45config GENERIC_IOMAP 46 bool 47 select GENERIC_PCI_IOMAP 48 49config STMP_DEVICE 50 bool 51 52config ARCH_USE_CMPXCHG_LOCKREF 53 bool 54 55config ARCH_HAS_FAST_MULTIPLIER 56 bool 57 58config INDIRECT_PIO 59 bool "Access I/O in non-MMIO mode" 60 depends on ARM64 61 help 62 On some platforms where no separate I/O space exists, there are I/O 63 hosts which can not be accessed in MMIO mode. Using the logical PIO 64 mechanism, the host-local I/O resource can be mapped into system 65 logic PIO space shared with MMIO hosts, such as PCI/PCIe, then the 66 system can access the I/O devices with the mapped-logic PIO through 67 I/O accessors. 68 69 This way has relatively little I/O performance cost. Please make 70 sure your devices really need this configure item enabled. 71 72 When in doubt, say N. 73 74config CRC_CCITT 75 tristate "CRC-CCITT functions" 76 help 77 This option is provided for the case where no in-kernel-tree 78 modules require CRC-CCITT functions, but a module built outside 79 the kernel tree does. Such modules that use library CRC-CCITT 80 functions require M here. 81 82config CRC16 83 tristate "CRC16 functions" 84 help 85 This option is provided for the case where no in-kernel-tree 86 modules require CRC16 functions, but a module built outside 87 the kernel tree does. Such modules that use library CRC16 88 functions require M here. 89 90config CRC_T10DIF 91 tristate "CRC calculation for the T10 Data Integrity Field" 92 select CRYPTO 93 select CRYPTO_CRCT10DIF 94 help 95 This option is only needed if a module that's not in the 96 kernel tree needs to calculate CRC checks for use with the 97 SCSI data integrity subsystem. 98 99config CRC_ITU_T 100 tristate "CRC ITU-T V.41 functions" 101 help 102 This option is provided for the case where no in-kernel-tree 103 modules require CRC ITU-T V.41 functions, but a module built outside 104 the kernel tree does. Such modules that use library CRC ITU-T V.41 105 functions require M here. 106 107config CRC32 108 tristate "CRC32/CRC32c functions" 109 default y 110 select BITREVERSE 111 help 112 This option is provided for the case where no in-kernel-tree 113 modules require CRC32/CRC32c functions, but a module built outside 114 the kernel tree does. Such modules that use library CRC32/CRC32c 115 functions require M here. 116 117config CRC32_SELFTEST 118 tristate "CRC32 perform self test on init" 119 depends on CRC32 120 help 121 This option enables the CRC32 library functions to perform a 122 self test on initialization. The self test computes crc32_le 123 and crc32_be over byte strings with random alignment and length 124 and computes the total elapsed time and number of bytes processed. 125 126choice 127 prompt "CRC32 implementation" 128 depends on CRC32 129 default CRC32_SLICEBY8 130 help 131 This option allows a kernel builder to override the default choice 132 of CRC32 algorithm. Choose the default ("slice by 8") unless you 133 know that you need one of the others. 134 135config CRC32_SLICEBY8 136 bool "Slice by 8 bytes" 137 help 138 Calculate checksum 8 bytes at a time with a clever slicing algorithm. 139 This is the fastest algorithm, but comes with a 8KiB lookup table. 140 Most modern processors have enough cache to hold this table without 141 thrashing the cache. 142 143 This is the default implementation choice. Choose this one unless 144 you have a good reason not to. 145 146config CRC32_SLICEBY4 147 bool "Slice by 4 bytes" 148 help 149 Calculate checksum 4 bytes at a time with a clever slicing algorithm. 150 This is a bit slower than slice by 8, but has a smaller 4KiB lookup 151 table. 152 153 Only choose this option if you know what you are doing. 154 155config CRC32_SARWATE 156 bool "Sarwate's Algorithm (one byte at a time)" 157 help 158 Calculate checksum a byte at a time using Sarwate's algorithm. This 159 is not particularly fast, but has a small 256 byte lookup table. 160 161 Only choose this option if you know what you are doing. 162 163config CRC32_BIT 164 bool "Classic Algorithm (one bit at a time)" 165 help 166 Calculate checksum one bit at a time. This is VERY slow, but has 167 no lookup table. This is provided as a debugging option. 168 169 Only choose this option if you are debugging crc32. 170 171endchoice 172 173config CRC4 174 tristate "CRC4 functions" 175 help 176 This option is provided for the case where no in-kernel-tree 177 modules require CRC4 functions, but a module built outside 178 the kernel tree does. Such modules that use library CRC4 179 functions require M here. 180 181config CRC7 182 tristate "CRC7 functions" 183 help 184 This option is provided for the case where no in-kernel-tree 185 modules require CRC7 functions, but a module built outside 186 the kernel tree does. Such modules that use library CRC7 187 functions require M here. 188 189config LIBCRC32C 190 tristate "CRC32c (Castagnoli, et al) Cyclic Redundancy-Check" 191 select CRYPTO 192 select CRYPTO_CRC32C 193 help 194 This option is provided for the case where no in-kernel-tree 195 modules require CRC32c functions, but a module built outside the 196 kernel tree does. Such modules that use library CRC32c functions 197 require M here. See Castagnoli93. 198 Module will be libcrc32c. 199 200config CRC8 201 tristate "CRC8 function" 202 help 203 This option provides CRC8 function. Drivers may select this 204 when they need to do cyclic redundancy check according CRC8 205 algorithm. Module will be called crc8. 206 207config XXHASH 208 tristate 209 210config AUDIT_GENERIC 211 bool 212 depends on AUDIT && !AUDIT_ARCH 213 default y 214 215config AUDIT_ARCH_COMPAT_GENERIC 216 bool 217 default n 218 219config AUDIT_COMPAT_GENERIC 220 bool 221 depends on AUDIT_GENERIC && AUDIT_ARCH_COMPAT_GENERIC && COMPAT 222 default y 223 224config RANDOM32_SELFTEST 225 bool "PRNG perform self test on init" 226 default n 227 help 228 This option enables the 32 bit PRNG library functions to perform a 229 self test on initialization. 230 231# 232# compression support is select'ed if needed 233# 234config 842_COMPRESS 235 select CRC32 236 tristate 237 238config 842_DECOMPRESS 239 select CRC32 240 tristate 241 242config ZLIB_INFLATE 243 tristate 244 245config ZLIB_DEFLATE 246 tristate 247 select BITREVERSE 248 249config LZO_COMPRESS 250 tristate 251 252config LZO_DECOMPRESS 253 tristate 254 255config LZ4_COMPRESS 256 tristate 257 258config LZ4HC_COMPRESS 259 tristate 260 261config LZ4_DECOMPRESS 262 tristate 263 264config ZSTD_COMPRESS 265 select XXHASH 266 tristate 267 268config ZSTD_DECOMPRESS 269 select XXHASH 270 tristate 271 272source "lib/xz/Kconfig" 273 274# 275# These all provide a common interface (hence the apparent duplication with 276# ZLIB_INFLATE; DECOMPRESS_GZIP is just a wrapper.) 277# 278config DECOMPRESS_GZIP 279 select ZLIB_INFLATE 280 tristate 281 282config DECOMPRESS_BZIP2 283 tristate 284 285config DECOMPRESS_LZMA 286 tristate 287 288config DECOMPRESS_XZ 289 select XZ_DEC 290 tristate 291 292config DECOMPRESS_LZO 293 select LZO_DECOMPRESS 294 tristate 295 296config DECOMPRESS_LZ4 297 select LZ4_DECOMPRESS 298 tristate 299 300# 301# Generic allocator support is selected if needed 302# 303config GENERIC_ALLOCATOR 304 bool 305 306# 307# reed solomon support is select'ed if needed 308# 309config REED_SOLOMON 310 tristate 311 312config REED_SOLOMON_ENC8 313 bool 314 315config REED_SOLOMON_DEC8 316 bool 317 318config REED_SOLOMON_ENC16 319 bool 320 321config REED_SOLOMON_DEC16 322 bool 323 324# 325# BCH support is selected if needed 326# 327config BCH 328 tristate 329 330config BCH_CONST_PARAMS 331 bool 332 help 333 Drivers may select this option to force specific constant 334 values for parameters 'm' (Galois field order) and 't' 335 (error correction capability). Those specific values must 336 be set by declaring default values for symbols BCH_CONST_M 337 and BCH_CONST_T. 338 Doing so will enable extra compiler optimizations, 339 improving encoding and decoding performance up to 2x for 340 usual (m,t) values (typically such that m*t < 200). 341 When this option is selected, the BCH library supports 342 only a single (m,t) configuration. This is mainly useful 343 for NAND flash board drivers requiring known, fixed BCH 344 parameters. 345 346config BCH_CONST_M 347 int 348 range 5 15 349 help 350 Constant value for Galois field order 'm'. If 'k' is the 351 number of data bits to protect, 'm' should be chosen such 352 that (k + m*t) <= 2**m - 1. 353 Drivers should declare a default value for this symbol if 354 they select option BCH_CONST_PARAMS. 355 356config BCH_CONST_T 357 int 358 help 359 Constant value for error correction capability in bits 't'. 360 Drivers should declare a default value for this symbol if 361 they select option BCH_CONST_PARAMS. 362 363# 364# Textsearch support is select'ed if needed 365# 366config TEXTSEARCH 367 bool 368 369config TEXTSEARCH_KMP 370 tristate 371 372config TEXTSEARCH_BM 373 tristate 374 375config TEXTSEARCH_FSM 376 tristate 377 378config BTREE 379 bool 380 381config INTERVAL_TREE 382 bool 383 help 384 Simple, embeddable, interval-tree. Can find the start of an 385 overlapping range in log(n) time and then iterate over all 386 overlapping nodes. The algorithm is implemented as an 387 augmented rbtree. 388 389 See: 390 391 Documentation/rbtree.txt 392 393 for more information. 394 395config RADIX_TREE_MULTIORDER 396 bool 397 398config ASSOCIATIVE_ARRAY 399 bool 400 help 401 Generic associative array. Can be searched and iterated over whilst 402 it is being modified. It is also reasonably quick to search and 403 modify. The algorithms are non-recursive, and the trees are highly 404 capacious. 405 406 See: 407 408 Documentation/core-api/assoc_array.rst 409 410 for more information. 411 412config HAS_IOMEM 413 bool 414 depends on !NO_IOMEM 415 select GENERIC_IO 416 default y 417 418config HAS_IOPORT_MAP 419 bool 420 depends on HAS_IOMEM && !NO_IOPORT_MAP 421 default y 422 423source "kernel/dma/Kconfig" 424 425config SGL_ALLOC 426 bool 427 default n 428 429config IOMMU_HELPER 430 bool 431 432config CHECK_SIGNATURE 433 bool 434 435config CPUMASK_OFFSTACK 436 bool "Force CPU masks off stack" if DEBUG_PER_CPU_MAPS 437 help 438 Use dynamic allocation for cpumask_var_t, instead of putting 439 them on the stack. This is a bit more expensive, but avoids 440 stack overflow. 441 442config CPU_RMAP 443 bool 444 depends on SMP 445 446config DQL 447 bool 448 449config GLOB 450 bool 451# This actually supports modular compilation, but the module overhead 452# is ridiculous for the amount of code involved. Until an out-of-tree 453# driver asks for it, we'll just link it directly it into the kernel 454# when required. Since we're ignoring out-of-tree users, there's also 455# no need bother prompting for a manual decision: 456# prompt "glob_match() function" 457 help 458 This option provides a glob_match function for performing 459 simple text pattern matching. It originated in the ATA code 460 to blacklist particular drive models, but other device drivers 461 may need similar functionality. 462 463 All drivers in the Linux kernel tree that require this function 464 should automatically select this option. Say N unless you 465 are compiling an out-of tree driver which tells you that it 466 depends on this. 467 468config GLOB_SELFTEST 469 tristate "glob self-test on init" 470 depends on GLOB 471 help 472 This option enables a simple self-test of the glob_match 473 function on startup. It is primarily useful for people 474 working on the code to ensure they haven't introduced any 475 regressions. 476 477 It only adds a little bit of code and slows kernel boot (or 478 module load) by a small amount, so you're welcome to play with 479 it, but you probably don't need it. 480 481# 482# Netlink attribute parsing support is select'ed if needed 483# 484config NLATTR 485 bool 486 487# 488# Generic 64-bit atomic support is selected if needed 489# 490config GENERIC_ATOMIC64 491 bool 492 493config LRU_CACHE 494 tristate 495 496config CLZ_TAB 497 bool 498 499config CORDIC 500 tristate "CORDIC algorithm" 501 help 502 This option provides an implementation of the CORDIC algorithm; 503 calculations are in fixed point. Module will be called cordic. 504 505config DDR 506 bool "JEDEC DDR data" 507 help 508 Data from JEDEC specs for DDR SDRAM memories, 509 particularly the AC timing parameters and addressing 510 information. This data is useful for drivers handling 511 DDR SDRAM controllers. 512 513config IRQ_POLL 514 bool "IRQ polling library" 515 help 516 Helper library to poll interrupt mitigation using polling. 517 518config MPILIB 519 tristate 520 select CLZ_TAB 521 help 522 Multiprecision maths library from GnuPG. 523 It is used to implement RSA digital signature verification, 524 which is used by IMA/EVM digital signature extension. 525 526config SIGNATURE 527 tristate 528 depends on KEYS 529 select CRYPTO 530 select CRYPTO_SHA1 531 select MPILIB 532 help 533 Digital signature verification. Currently only RSA is supported. 534 Implementation is done using GnuPG MPI library 535 536# 537# libfdt files, only selected if needed. 538# 539config LIBFDT 540 bool 541 542config OID_REGISTRY 543 tristate 544 help 545 Enable fast lookup object identifier registry. 546 547config UCS2_STRING 548 tristate 549 550source "lib/fonts/Kconfig" 551 552config SG_SPLIT 553 def_bool n 554 help 555 Provides a helper to split scatterlists into chunks, each chunk being 556 a scatterlist. This should be selected by a driver or an API which 557 whishes to split a scatterlist amongst multiple DMA channels. 558 559config SG_POOL 560 def_bool n 561 help 562 Provides a helper to allocate chained scatterlists. This should be 563 selected by a driver or an API which whishes to allocate chained 564 scatterlist. 565 566# 567# sg chaining option 568# 569 570config ARCH_HAS_SG_CHAIN 571 def_bool n 572 573config ARCH_HAS_PMEM_API 574 bool 575 576config ARCH_HAS_UACCESS_FLUSHCACHE 577 bool 578 579config ARCH_HAS_UACCESS_MCSAFE 580 bool 581 582config STACKDEPOT 583 bool 584 select STACKTRACE 585 586config SBITMAP 587 bool 588 589config PARMAN 590 tristate "parman" if COMPILE_TEST 591 592config PRIME_NUMBERS 593 tristate 594 595config STRING_SELFTEST 596 tristate "Test string functions" 597 598endmenu 599 600config GENERIC_LIB_ASHLDI3 601 bool 602 603config GENERIC_LIB_ASHRDI3 604 bool 605 606config GENERIC_LIB_LSHRDI3 607 bool 608 609config GENERIC_LIB_MULDI3 610 bool 611 612config GENERIC_LIB_CMPDI2 613 bool 614 615config GENERIC_LIB_UCMPDI2 616 bool 617