lib/Kconfig

   1 #
   2 # Library configuration
   3 #
   4
   5 config BINARY_PRINTF
   6         def_bool n
   7
   8 menu "Library routines"
   9
  10 config RAID6_PQ
  11         tristate
  12
  13 config BITREVERSE
  14         tristate
  15
  16 config 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
  24 config RATIONAL
  25         bool
  26
  27 config GENERIC_STRNCPY_FROM_USER
  28         bool
  29
  30 config GENERIC_STRNLEN_USER
  31         bool
  32
  33 config GENERIC_NET_UTILS
  34         bool
  35
  36 config GENERIC_FIND_FIRST_BIT
  37         bool
  38
  39 config NO_GENERIC_PCI_IOPORT_MAP
  40         bool
  41
  42 config GENERIC_PCI_IOMAP
  43         bool
  44
  45 config GENERIC_IOMAP
  46         bool
  47         select GENERIC_PCI_IOMAP
  48
  49 config STMP_DEVICE
  50         bool
  51
  52 config ARCH_USE_CMPXCHG_LOCKREF
  53         bool
  54
  55 config ARCH_HAS_FAST_MULTIPLIER
  56         bool
  57
  58 config 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           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
  73 config 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
  81 config 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
  89 config 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
  98 config 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
 106 config 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
 116 config 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
 125 choice
 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
 134 config 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
 145 config 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
 154 config 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
 162 config 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
 170 endchoice
 171
 172 config CRC4
 173         tristate "CRC4 functions"
 174         help
 175           This option is provided for the case where no in-kernel-tree
 176           modules require CRC4 functions, but a module built outside
 177           the kernel tree does. Such modules that use library CRC4
 178           functions require M here.
 179
 180 config CRC7
 181         tristate "CRC7 functions"
 182         help
 183           This option is provided for the case where no in-kernel-tree
 184           modules require CRC7 functions, but a module built outside
 185           the kernel tree does. Such modules that use library CRC7
 186           functions require M here.
 187
 188 config LIBCRC32C
 189         tristate "CRC32c (Castagnoli, et al) Cyclic Redundancy-Check"
 190         select CRYPTO
 191         select CRYPTO_CRC32C
 192         help
 193           This option is provided for the case where no in-kernel-tree
 194           modules require CRC32c functions, but a module built outside the
 195           kernel tree does. Such modules that use library CRC32c functions
 196           require M here.  See Castagnoli93.
 197           Module will be libcrc32c.
 198
 199 config CRC8
 200         tristate "CRC8 function"
 201         help
 202           This option provides CRC8 function. Drivers may select this
 203           when they need to do cyclic redundancy check according CRC8
 204           algorithm. Module will be called crc8.
 205
 206 config XXHASH
 207         tristate
 208
 209 config AUDIT_GENERIC
 210         bool
 211         depends on AUDIT && !AUDIT_ARCH
 212         default y
 213
 214 config AUDIT_ARCH_COMPAT_GENERIC
 215         bool
 216         default n
 217
 218 config AUDIT_COMPAT_GENERIC
 219         bool
 220         depends on AUDIT_GENERIC && AUDIT_ARCH_COMPAT_GENERIC && COMPAT
 221         default y
 222
 223 config RANDOM32_SELFTEST
 224         bool "PRNG perform self test on init"
 225         default n
 226         help
 227           This option enables the 32 bit PRNG library functions to perform a
 228           self test on initialization.
 229
 230 #
 231 # compression support is select'ed if needed
 232 #
 233 config 842_COMPRESS
 234         select CRC32
 235         tristate
 236
 237 config 842_DECOMPRESS
 238         select CRC32
 239         tristate
 240
 241 config ZLIB_INFLATE
 242         tristate
 243
 244 config ZLIB_DEFLATE
 245         tristate
 246         select BITREVERSE
 247
 248 config LZO_COMPRESS
 249         tristate
 250
 251 config LZO_DECOMPRESS
 252         tristate
 253
 254 config LZ4_COMPRESS
 255         tristate
 256
 257 config LZ4HC_COMPRESS
 258         tristate
 259
 260 config LZ4_DECOMPRESS
 261         tristate
 262
 263 config ZSTD_COMPRESS
 264         select XXHASH
 265         tristate
 266
 267 config ZSTD_DECOMPRESS
 268         select XXHASH
 269         tristate
 270
 271 source "lib/xz/Kconfig"
 272
 273 #
 274 # These all provide a common interface (hence the apparent duplication with
 275 # ZLIB_INFLATE; DECOMPRESS_GZIP is just a wrapper.)
 276 #
 277 config DECOMPRESS_GZIP
 278         select ZLIB_INFLATE
 279         tristate
 280
 281 config DECOMPRESS_BZIP2
 282         tristate
 283
 284 config DECOMPRESS_LZMA
 285         tristate
 286
 287 config DECOMPRESS_XZ
 288         select XZ_DEC
 289         tristate
 290
 291 config DECOMPRESS_LZO
 292         select LZO_DECOMPRESS
 293         tristate
 294
 295 config DECOMPRESS_LZ4
 296         select LZ4_DECOMPRESS
 297         tristate
 298
 299 #
 300 # Generic allocator support is selected if needed
 301 #
 302 config GENERIC_ALLOCATOR
 303         bool
 304
 305 #
 306 # reed solomon support is select'ed if needed
 307 #
 308 config REED_SOLOMON
 309         tristate
 310
 311 config REED_SOLOMON_ENC8
 312         bool
 313
 314 config REED_SOLOMON_DEC8
 315         bool
 316
 317 config REED_SOLOMON_ENC16
 318         bool
 319
 320 config REED_SOLOMON_DEC16
 321         bool
 322
 323 #
 324 # BCH support is selected if needed
 325 #
 326 config BCH
 327         tristate
 328
 329 config BCH_CONST_PARAMS
 330         bool
 331         help
 332           Drivers may select this option to force specific constant
 333           values for parameters 'm' (Galois field order) and 't'
 334           (error correction capability). Those specific values must
 335           be set by declaring default values for symbols BCH_CONST_M
 336           and BCH_CONST_T.
 337           Doing so will enable extra compiler optimizations,
 338           improving encoding and decoding performance up to 2x for
 339           usual (m,t) values (typically such that m*t < 200).
 340           When this option is selected, the BCH library supports
 341           only a single (m,t) configuration. This is mainly useful
 342           for NAND flash board drivers requiring known, fixed BCH
 343           parameters.
 344
 345 config BCH_CONST_M
 346         int
 347         range 5 15
 348         help
 349           Constant value for Galois field order 'm'. If 'k' is the
 350           number of data bits to protect, 'm' should be chosen such
 351           that (k + m*t) <= 2**m - 1.
 352           Drivers should declare a default value for this symbol if
 353           they select option BCH_CONST_PARAMS.
 354
 355 config BCH_CONST_T
 356         int
 357         help
 358           Constant value for error correction capability in bits 't'.
 359           Drivers should declare a default value for this symbol if
 360           they select option BCH_CONST_PARAMS.
 361
 362 #
 363 # Textsearch support is select'ed if needed
 364 #
 365 config TEXTSEARCH
 366         bool
 367
 368 config TEXTSEARCH_KMP
 369         tristate
 370
 371 config TEXTSEARCH_BM
 372         tristate
 373
 374 config TEXTSEARCH_FSM
 375         tristate
 376
 377 config BTREE
 378         bool
 379
 380 config INTERVAL_TREE
 381         bool
 382         help
 383           Simple, embeddable, interval-tree. Can find the start of an
 384           overlapping range in log(n) time and then iterate over all
 385           overlapping nodes. The algorithm is implemented as an
 386           augmented rbtree.
 387
 388           See:
 389
 390                 Documentation/rbtree.txt
 391
 392           for more information.
 393
 394 config RADIX_TREE_MULTIORDER
 395         bool
 396
 397 config ASSOCIATIVE_ARRAY
 398         bool
 399         help
 400           Generic associative array.  Can be searched and iterated over whilst
 401           it is being modified.  It is also reasonably quick to search and
 402           modify.  The algorithms are non-recursive, and the trees are highly
 403           capacious.
 404
 405           See:
 406
 407                 Documentation/assoc_array.txt
 408
 409           for more information.
 410
 411 config HAS_IOMEM
 412         bool
 413         depends on !NO_IOMEM
 414         select GENERIC_IO
 415         default y
 416
 417 config HAS_IOPORT_MAP
 418         bool
 419         depends on HAS_IOMEM && !NO_IOPORT_MAP
 420         default y
 421
 422 config HAS_DMA
 423         bool
 424         depends on !NO_DMA
 425         default y
 426
 427 config DMA_NOOP_OPS
 428         bool
 429         depends on HAS_DMA && (!64BIT || ARCH_DMA_ADDR_T_64BIT)
 430         default n
 431
 432 config DMA_VIRT_OPS
 433         bool
 434         depends on HAS_DMA && (!64BIT || ARCH_DMA_ADDR_T_64BIT)
 435         default n
 436
 437 config CHECK_SIGNATURE
 438         bool
 439
 440 config CPUMASK_OFFSTACK
 441         bool "Force CPU masks off stack" if DEBUG_PER_CPU_MAPS
 442         help
 443           Use dynamic allocation for cpumask_var_t, instead of putting
 444           them on the stack.  This is a bit more expensive, but avoids
 445           stack overflow.
 446
 447 config CPU_RMAP
 448         bool
 449         depends on SMP
 450
 451 config DQL
 452         bool
 453
 454 config GLOB
 455         bool
 456 #       This actually supports modular compilation, but the module overhead
 457 #       is ridiculous for the amount of code involved.  Until an out-of-tree
 458 #       driver asks for it, we'll just link it directly it into the kernel
 459 #       when required.  Since we're ignoring out-of-tree users, there's also
 460 #       no need bother prompting for a manual decision:
 461 #       prompt "glob_match() function"
 462         help
 463           This option provides a glob_match function for performing
 464           simple text pattern matching.  It originated in the ATA code
 465           to blacklist particular drive models, but other device drivers
 466           may need similar functionality.
 467
 468           All drivers in the Linux kernel tree that require this function
 469           should automatically select this option.  Say N unless you
 470           are compiling an out-of tree driver which tells you that it
 471           depends on this.
 472
 473 config GLOB_SELFTEST
 474         tristate "glob self-test on init"
 475         depends on GLOB
 476         help
 477           This option enables a simple self-test of the glob_match
 478           function on startup.  It is primarily useful for people
 479           working on the code to ensure they haven't introduced any
 480           regressions.
 481
 482           It only adds a little bit of code and slows kernel boot (or
 483           module load) by a small amount, so you're welcome to play with
 484           it, but you probably don't need it.
 485
 486 #
 487 # Netlink attribute parsing support is select'ed if needed
 488 #
 489 config NLATTR
 490         bool
 491
 492 #
 493 # Generic 64-bit atomic support is selected if needed
 494 #
 495 config GENERIC_ATOMIC64
 496        bool
 497
 498 config LRU_CACHE
 499         tristate
 500
 501 config CLZ_TAB
 502         bool
 503
 504 config CORDIC
 505         tristate "CORDIC algorithm"
 506         help
 507           This option provides an implementation of the CORDIC algorithm;
 508           calculations are in fixed point. Module will be called cordic.
 509
 510 config DDR
 511         bool "JEDEC DDR data"
 512         help
 513           Data from JEDEC specs for DDR SDRAM memories,
 514           particularly the AC timing parameters and addressing
 515           information. This data is useful for drivers handling
 516           DDR SDRAM controllers.
 517
 518 config IRQ_POLL
 519         bool "IRQ polling library"
 520         help
 521           Helper library to poll interrupt mitigation using polling.
 522
 523 config MPILIB
 524         tristate
 525         select CLZ_TAB
 526         help
 527           Multiprecision maths library from GnuPG.
 528           It is used to implement RSA digital signature verification,
 529           which is used by IMA/EVM digital signature extension.
 530
 531 config SIGNATURE
 532         tristate
 533         depends on KEYS
 534         select CRYPTO
 535         select CRYPTO_SHA1
 536         select MPILIB
 537         help
 538           Digital signature verification. Currently only RSA is supported.
 539           Implementation is done using GnuPG MPI library
 540
 541 #
 542 # libfdt files, only selected if needed.
 543 #
 544 config LIBFDT
 545         bool
 546
 547 config OID_REGISTRY
 548         tristate
 549         help
 550           Enable fast lookup object identifier registry.
 551
 552 config UCS2_STRING
 553         tristate
 554
 555 source "lib/fonts/Kconfig"
 556
 557 config SG_SPLIT
 558         def_bool n
 559         help
 560          Provides a helper to split scatterlists into chunks, each chunk being
 561          a scatterlist. This should be selected by a driver or an API which
 562          whishes to split a scatterlist amongst multiple DMA channels.
 563
 564 config SG_POOL
 565         def_bool n
 566         help
 567          Provides a helper to allocate chained scatterlists. This should be
 568          selected by a driver or an API which whishes to allocate chained
 569          scatterlist.
 570
 571 #
 572 # sg chaining option
 573 #
 574
 575 config ARCH_HAS_SG_CHAIN
 576         def_bool n
 577
 578 config ARCH_HAS_PMEM_API
 579         bool
 580
 581 config ARCH_HAS_UACCESS_FLUSHCACHE
 582         bool
 583
 584 config STACKDEPOT
 585         bool
 586         select STACKTRACE
 587
 588 config SBITMAP
 589         bool
 590
 591 config PARMAN
 592         tristate "parman" if COMPILE_TEST
 593
 594 config PRIME_NUMBERS
 595         tristate
 596
 597 config STRING_SELFTEST
 598         tristate "Test string functions"
 599
 600 endmenu
 601
 602 config GENERIC_ASHLDI3
 603         bool
 604
 605 config GENERIC_ASHRDI3
 606         bool
 607
 608 config GENERIC_LSHRDI3
 609         bool
 610
 611 config GENERIC_MULDI3
 612         bool
 613
 614 config GENERIC_CMPDI2
 615         bool
 616
 617 config GENERIC_UCMPDI2
 618         bool