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 help 20 This option enables the use of hardware bit-reversal instructions on 21 architectures which support such operations. 22 23config RATIONAL 24 bool 25 26config GENERIC_STRNCPY_FROM_USER 27 bool 28 29config GENERIC_STRNLEN_USER 30 bool 31 32config GENERIC_NET_UTILS 33 bool 34 35config GENERIC_FIND_FIRST_BIT 36 bool 37 38config NO_GENERIC_PCI_IOPORT_MAP 39 bool 40 41config GENERIC_PCI_IOMAP 42 bool 43 44config GENERIC_IOMAP 45 bool 46 select GENERIC_PCI_IOMAP 47 48config STMP_DEVICE 49 bool 50 51config ARCH_USE_CMPXCHG_LOCKREF 52 bool 53 54config ARCH_HAS_FAST_MULTIPLIER 55 bool 56 57config INDIRECT_PIO 58 bool "Access I/O in non-MMIO mode" 59 depends on ARM64 60 help 61 On some platforms where no separate I/O space exists, there are I/O 62 hosts which can not be accessed in MMIO mode. Using the logical PIO 63 mechanism, the host-local I/O resource can be mapped into system 64 logic PIO space shared with MMIO hosts, such as PCI/PCIe, then the 65 system can access the I/O devices with the mapped-logic PIO through 66 I/O accessors. 67 68 This way has relatively little I/O performance cost. Please make 69 sure your devices really need this configure item enabled. 70 71 When in doubt, say N. 72 73config CRC_CCITT 74 tristate "CRC-CCITT functions" 75 help 76 This option is provided for the case where no in-kernel-tree 77 modules require CRC-CCITT functions, but a module built outside 78 the kernel tree does. Such modules that use library CRC-CCITT 79 functions require M here. 80 81config CRC16 82 tristate "CRC16 functions" 83 help 84 This option is provided for the case where no in-kernel-tree 85 modules require CRC16 functions, but a module built outside 86 the kernel tree does. Such modules that use library CRC16 87 functions require M here. 88 89config CRC_T10DIF 90 tristate "CRC calculation for the T10 Data Integrity Field" 91 select CRYPTO 92 select CRYPTO_CRCT10DIF 93 help 94 This option is only needed if a module that's not in the 95 kernel tree needs to calculate CRC checks for use with the 96 SCSI data integrity subsystem. 97 98config CRC_ITU_T 99 tristate "CRC ITU-T V.41 functions" 100 help 101 This option is provided for the case where no in-kernel-tree 102 modules require CRC ITU-T V.41 functions, but a module built outside 103 the kernel tree does. Such modules that use library CRC ITU-T V.41 104 functions require M here. 105 106config CRC32 107 tristate "CRC32/CRC32c functions" 108 default y 109 select BITREVERSE 110 help 111 This option is provided for the case where no in-kernel-tree 112 modules require CRC32/CRC32c functions, but a module built outside 113 the kernel tree does. Such modules that use library CRC32/CRC32c 114 functions require M here. 115 116config CRC32_SELFTEST 117 tristate "CRC32 perform self test on init" 118 depends on CRC32 119 help 120 This option enables the CRC32 library functions to perform a 121 self test on initialization. The self test computes crc32_le 122 and crc32_be over byte strings with random alignment and length 123 and computes the total elapsed time and number of bytes processed. 124 125choice 126 prompt "CRC32 implementation" 127 depends on CRC32 128 default CRC32_SLICEBY8 129 help 130 This option allows a kernel builder to override the default choice 131 of CRC32 algorithm. Choose the default ("slice by 8") unless you 132 know that you need one of the others. 133 134config CRC32_SLICEBY8 135 bool "Slice by 8 bytes" 136 help 137 Calculate checksum 8 bytes at a time with a clever slicing algorithm. 138 This is the fastest algorithm, but comes with a 8KiB lookup table. 139 Most modern processors have enough cache to hold this table without 140 thrashing the cache. 141 142 This is the default implementation choice. Choose this one unless 143 you have a good reason not to. 144 145config CRC32_SLICEBY4 146 bool "Slice by 4 bytes" 147 help 148 Calculate checksum 4 bytes at a time with a clever slicing algorithm. 149 This is a bit slower than slice by 8, but has a smaller 4KiB lookup 150 table. 151 152 Only choose this option if you know what you are doing. 153 154config CRC32_SARWATE 155 bool "Sarwate's Algorithm (one byte at a time)" 156 help 157 Calculate checksum a byte at a time using Sarwate's algorithm. This 158 is not particularly fast, but has a small 256 byte lookup table. 159 160 Only choose this option if you know what you are doing. 161 162config CRC32_BIT 163 bool "Classic Algorithm (one bit at a time)" 164 help 165 Calculate checksum one bit at a time. This is VERY slow, but has 166 no lookup table. This is provided as a debugging option. 167 168 Only choose this option if you are debugging crc32. 169 170endchoice 171 172config CRC64 173 tristate "CRC64 functions" 174 help 175 This option is provided for the case where no in-kernel-tree 176 modules require CRC64 functions, but a module built outside 177 the kernel tree does. Such modules that use library CRC64 178 functions require M here. 179 180config CRC4 181 tristate "CRC4 functions" 182 help 183 This option is provided for the case where no in-kernel-tree 184 modules require CRC4 functions, but a module built outside 185 the kernel tree does. Such modules that use library CRC4 186 functions require M here. 187 188config CRC7 189 tristate "CRC7 functions" 190 help 191 This option is provided for the case where no in-kernel-tree 192 modules require CRC7 functions, but a module built outside 193 the kernel tree does. Such modules that use library CRC7 194 functions require M here. 195 196config LIBCRC32C 197 tristate "CRC32c (Castagnoli, et al) Cyclic Redundancy-Check" 198 select CRYPTO 199 select CRYPTO_CRC32C 200 help 201 This option is provided for the case where no in-kernel-tree 202 modules require CRC32c functions, but a module built outside the 203 kernel tree does. Such modules that use library CRC32c functions 204 require M here. See Castagnoli93. 205 Module will be libcrc32c. 206 207config CRC8 208 tristate "CRC8 function" 209 help 210 This option provides CRC8 function. Drivers may select this 211 when they need to do cyclic redundancy check according CRC8 212 algorithm. Module will be called crc8. 213 214config XXHASH 215 tristate 216 217config AUDIT_GENERIC 218 bool 219 depends on AUDIT && !AUDIT_ARCH 220 default y 221 222config AUDIT_ARCH_COMPAT_GENERIC 223 bool 224 default n 225 226config AUDIT_COMPAT_GENERIC 227 bool 228 depends on AUDIT_GENERIC && AUDIT_ARCH_COMPAT_GENERIC && COMPAT 229 default y 230 231config RANDOM32_SELFTEST 232 bool "PRNG perform self test on init" 233 help 234 This option enables the 32 bit PRNG library functions to perform a 235 self test on initialization. 236 237# 238# compression support is select'ed if needed 239# 240config 842_COMPRESS 241 select CRC32 242 tristate 243 244config 842_DECOMPRESS 245 select CRC32 246 tristate 247 248config ZLIB_INFLATE 249 tristate 250 251config ZLIB_DEFLATE 252 tristate 253 select BITREVERSE 254 255config LZO_COMPRESS 256 tristate 257 258config LZO_DECOMPRESS 259 tristate 260 261config LZ4_COMPRESS 262 tristate 263 264config LZ4HC_COMPRESS 265 tristate 266 267config LZ4_DECOMPRESS 268 tristate 269 270config ZSTD_COMPRESS 271 select XXHASH 272 tristate 273 274config ZSTD_DECOMPRESS 275 select XXHASH 276 tristate 277 278source "lib/xz/Kconfig" 279 280# 281# These all provide a common interface (hence the apparent duplication with 282# ZLIB_INFLATE; DECOMPRESS_GZIP is just a wrapper.) 283# 284config DECOMPRESS_GZIP 285 select ZLIB_INFLATE 286 tristate 287 288config DECOMPRESS_BZIP2 289 tristate 290 291config DECOMPRESS_LZMA 292 tristate 293 294config DECOMPRESS_XZ 295 select XZ_DEC 296 tristate 297 298config DECOMPRESS_LZO 299 select LZO_DECOMPRESS 300 tristate 301 302config DECOMPRESS_LZ4 303 select LZ4_DECOMPRESS 304 tristate 305 306# 307# Generic allocator support is selected if needed 308# 309config GENERIC_ALLOCATOR 310 bool 311 312# 313# reed solomon support is select'ed if needed 314# 315config REED_SOLOMON 316 tristate 317 318config REED_SOLOMON_ENC8 319 bool 320 321config REED_SOLOMON_DEC8 322 bool 323 324config REED_SOLOMON_ENC16 325 bool 326 327config REED_SOLOMON_DEC16 328 bool 329 330# 331# BCH support is selected if needed 332# 333config BCH 334 tristate 335 336config BCH_CONST_PARAMS 337 bool 338 help 339 Drivers may select this option to force specific constant 340 values for parameters 'm' (Galois field order) and 't' 341 (error correction capability). Those specific values must 342 be set by declaring default values for symbols BCH_CONST_M 343 and BCH_CONST_T. 344 Doing so will enable extra compiler optimizations, 345 improving encoding and decoding performance up to 2x for 346 usual (m,t) values (typically such that m*t < 200). 347 When this option is selected, the BCH library supports 348 only a single (m,t) configuration. This is mainly useful 349 for NAND flash board drivers requiring known, fixed BCH 350 parameters. 351 352config BCH_CONST_M 353 int 354 range 5 15 355 help 356 Constant value for Galois field order 'm'. If 'k' is the 357 number of data bits to protect, 'm' should be chosen such 358 that (k + m*t) <= 2**m - 1. 359 Drivers should declare a default value for this symbol if 360 they select option BCH_CONST_PARAMS. 361 362config BCH_CONST_T 363 int 364 help 365 Constant value for error correction capability in bits 't'. 366 Drivers should declare a default value for this symbol if 367 they select option BCH_CONST_PARAMS. 368 369# 370# Textsearch support is select'ed if needed 371# 372config TEXTSEARCH 373 bool 374 375config TEXTSEARCH_KMP 376 tristate 377 378config TEXTSEARCH_BM 379 tristate 380 381config TEXTSEARCH_FSM 382 tristate 383 384config BTREE 385 bool 386 387config INTERVAL_TREE 388 bool 389 help 390 Simple, embeddable, interval-tree. Can find the start of an 391 overlapping range in log(n) time and then iterate over all 392 overlapping nodes. The algorithm is implemented as an 393 augmented rbtree. 394 395 See: 396 397 Documentation/rbtree.txt 398 399 for more information. 400 401config RADIX_TREE_MULTIORDER 402 bool 403 404config ASSOCIATIVE_ARRAY 405 bool 406 help 407 Generic associative array. Can be searched and iterated over whilst 408 it is being modified. It is also reasonably quick to search and 409 modify. The algorithms are non-recursive, and the trees are highly 410 capacious. 411 412 See: 413 414 Documentation/core-api/assoc_array.rst 415 416 for more information. 417 418config HAS_IOMEM 419 bool 420 depends on !NO_IOMEM 421 select GENERIC_IO 422 default y 423 424config HAS_IOPORT_MAP 425 bool 426 depends on HAS_IOMEM && !NO_IOPORT_MAP 427 default y 428 429source "kernel/dma/Kconfig" 430 431config SGL_ALLOC 432 bool 433 default n 434 435config IOMMU_HELPER 436 bool 437 438config CHECK_SIGNATURE 439 bool 440 441config CPUMASK_OFFSTACK 442 bool "Force CPU masks off stack" if DEBUG_PER_CPU_MAPS 443 help 444 Use dynamic allocation for cpumask_var_t, instead of putting 445 them on the stack. This is a bit more expensive, but avoids 446 stack overflow. 447 448config CPU_RMAP 449 bool 450 depends on SMP 451 452config DQL 453 bool 454 455config GLOB 456 bool 457# This actually supports modular compilation, but the module overhead 458# is ridiculous for the amount of code involved. Until an out-of-tree 459# driver asks for it, we'll just link it directly it into the kernel 460# when required. Since we're ignoring out-of-tree users, there's also 461# no need bother prompting for a manual decision: 462# prompt "glob_match() function" 463 help 464 This option provides a glob_match function for performing 465 simple text pattern matching. It originated in the ATA code 466 to blacklist particular drive models, but other device drivers 467 may need similar functionality. 468 469 All drivers in the Linux kernel tree that require this function 470 should automatically select this option. Say N unless you 471 are compiling an out-of tree driver which tells you that it 472 depends on this. 473 474config GLOB_SELFTEST 475 tristate "glob self-test on init" 476 depends on GLOB 477 help 478 This option enables a simple self-test of the glob_match 479 function on startup. It is primarily useful for people 480 working on the code to ensure they haven't introduced any 481 regressions. 482 483 It only adds a little bit of code and slows kernel boot (or 484 module load) by a small amount, so you're welcome to play with 485 it, but you probably don't need it. 486 487# 488# Netlink attribute parsing support is select'ed if needed 489# 490config NLATTR 491 bool 492 493# 494# Generic 64-bit atomic support is selected if needed 495# 496config GENERIC_ATOMIC64 497 bool 498 499config LRU_CACHE 500 tristate 501 502config CLZ_TAB 503 bool 504 505config CORDIC 506 tristate "CORDIC algorithm" 507 help 508 This option provides an implementation of the CORDIC algorithm; 509 calculations are in fixed point. Module will be called cordic. 510 511config DDR 512 bool "JEDEC DDR data" 513 help 514 Data from JEDEC specs for DDR SDRAM memories, 515 particularly the AC timing parameters and addressing 516 information. This data is useful for drivers handling 517 DDR SDRAM controllers. 518 519config IRQ_POLL 520 bool "IRQ polling library" 521 help 522 Helper library to poll interrupt mitigation using polling. 523 524config MPILIB 525 tristate 526 select CLZ_TAB 527 help 528 Multiprecision maths library from GnuPG. 529 It is used to implement RSA digital signature verification, 530 which is used by IMA/EVM digital signature extension. 531 532config SIGNATURE 533 tristate 534 depends on KEYS 535 select CRYPTO 536 select CRYPTO_SHA1 537 select MPILIB 538 help 539 Digital signature verification. Currently only RSA is supported. 540 Implementation is done using GnuPG MPI library 541 542# 543# libfdt files, only selected if needed. 544# 545config LIBFDT 546 bool 547 548config OID_REGISTRY 549 tristate 550 help 551 Enable fast lookup object identifier registry. 552 553config UCS2_STRING 554 tristate 555 556source "lib/fonts/Kconfig" 557 558config SG_SPLIT 559 def_bool n 560 help 561 Provides a helper to split scatterlists into chunks, each chunk being 562 a scatterlist. This should be selected by a driver or an API which 563 whishes to split a scatterlist amongst multiple DMA channels. 564 565config SG_POOL 566 def_bool n 567 help 568 Provides a helper to allocate chained scatterlists. This should be 569 selected by a driver or an API which whishes to allocate chained 570 scatterlist. 571 572# 573# sg chaining option 574# 575 576config ARCH_HAS_SG_CHAIN 577 def_bool n 578 579config ARCH_HAS_PMEM_API 580 bool 581 582config ARCH_HAS_UACCESS_FLUSHCACHE 583 bool 584 585config ARCH_HAS_UACCESS_MCSAFE 586 bool 587 588config STACKDEPOT 589 bool 590 select STACKTRACE 591 592config SBITMAP 593 bool 594 595config PARMAN 596 tristate "parman" if COMPILE_TEST 597 598config PRIME_NUMBERS 599 tristate 600 601config STRING_SELFTEST 602 tristate "Test string functions" 603 604endmenu 605 606config GENERIC_LIB_ASHLDI3 607 bool 608 609config GENERIC_LIB_ASHRDI3 610 bool 611 612config GENERIC_LIB_LSHRDI3 613 bool 614 615config GENERIC_LIB_MULDI3 616 bool 617 618config GENERIC_LIB_CMPDI2 619 bool 620 621config GENERIC_LIB_UCMPDI2 622 bool 623