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
  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
  74 config 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
  82 config 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
  90 config 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
  99 config 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
 107 config 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
 117 config 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
 126 choice
 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
 135 config 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
 146 config 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
 155 config 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
 163 config 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
 171 endchoice
 172
 173 config 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
 181 config 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
 189 config 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
 200 config 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
 207 config XXHASH
 208         tristate
 209
 210 config AUDIT_GENERIC
 211         bool
 212         depends on AUDIT && !AUDIT_ARCH
 213         default y
 214
 215 config AUDIT_ARCH_COMPAT_GENERIC
 216         bool
 217         default n
 218
 219 config AUDIT_COMPAT_GENERIC
 220         bool
 221         depends on AUDIT_GENERIC && AUDIT_ARCH_COMPAT_GENERIC && COMPAT
 222         default y
 223
 224 config 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 #
 234 config 842_COMPRESS
 235         select CRC32
 236         tristate
 237
 238 config 842_DECOMPRESS
 239         select CRC32
 240         tristate
 241
 242 config ZLIB_INFLATE
 243         tristate
 244
 245 config ZLIB_DEFLATE
 246         tristate
 247         select BITREVERSE
 248
 249 config LZO_COMPRESS
 250         tristate
 251
 252 config LZO_DECOMPRESS
 253         tristate
 254
 255 config LZ4_COMPRESS
 256         tristate
 257
 258 config LZ4HC_COMPRESS
 259         tristate
 260
 261 config LZ4_DECOMPRESS
 262         tristate
 263
 264 config ZSTD_COMPRESS
 265         select XXHASH
 266         tristate
 267
 268 config ZSTD_DECOMPRESS
 269         select XXHASH
 270         tristate
 271
 272 source "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 #
 278 config DECOMPRESS_GZIP
 279         select ZLIB_INFLATE
 280         tristate
 281
 282 config DECOMPRESS_BZIP2
 283         tristate
 284
 285 config DECOMPRESS_LZMA
 286         tristate
 287
 288 config DECOMPRESS_XZ
 289         select XZ_DEC
 290         tristate
 291
 292 config DECOMPRESS_LZO
 293         select LZO_DECOMPRESS
 294         tristate
 295
 296 config DECOMPRESS_LZ4
 297         select LZ4_DECOMPRESS
 298         tristate
 299
 300 #
 301 # Generic allocator support is selected if needed
 302 #
 303 config GENERIC_ALLOCATOR
 304         bool
 305
 306 #
 307 # reed solomon support is select'ed if needed
 308 #
 309 config REED_SOLOMON
 310         tristate
 311
 312 config REED_SOLOMON_ENC8
 313         bool
 314
 315 config REED_SOLOMON_DEC8
 316         bool
 317
 318 config REED_SOLOMON_ENC16
 319         bool
 320
 321 config REED_SOLOMON_DEC16
 322         bool
 323
 324 #
 325 # BCH support is selected if needed
 326 #
 327 config BCH
 328         tristate
 329
 330 config 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
 346 config 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
 356 config 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 #
 366 config TEXTSEARCH
 367         bool
 368
 369 config TEXTSEARCH_KMP
 370         tristate
 371
 372 config TEXTSEARCH_BM
 373         tristate
 374
 375 config TEXTSEARCH_FSM
 376         tristate
 377
 378 config BTREE
 379         bool
 380
 381 config 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
 395 config RADIX_TREE_MULTIORDER
 396         bool
 397
 398 config 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/assoc_array.txt
 409
 410           for more information.
 411
 412 config HAS_IOMEM
 413         bool
 414         depends on !NO_IOMEM
 415         select GENERIC_IO
 416         default y
 417
 418 config HAS_IOPORT_MAP
 419         bool
 420         depends on HAS_IOMEM && !NO_IOPORT_MAP
 421         default y
 422
 423 config HAS_DMA
 424         bool
 425         depends on !NO_DMA
 426         default y
 427
 428 config DMA_NOOP_OPS
 429         bool
 430         depends on HAS_DMA && (!64BIT || ARCH_DMA_ADDR_T_64BIT)
 431         default n
 432
 433 config DMA_VIRT_OPS
 434         bool
 435         depends on HAS_DMA && (!64BIT || ARCH_DMA_ADDR_T_64BIT)
 436         default n
 437
 438 config CHECK_SIGNATURE
 439         bool
 440
 441 config 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
 448 config CPU_RMAP
 449         bool
 450         depends on SMP
 451
 452 config DQL
 453         bool
 454
 455 config 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
 474 config 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 #
 490 config NLATTR
 491         bool
 492
 493 #
 494 # Generic 64-bit atomic support is selected if needed
 495 #
 496 config GENERIC_ATOMIC64
 497        bool
 498
 499 config LRU_CACHE
 500         tristate
 501
 502 config CLZ_TAB
 503         bool
 504
 505 config 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
 511 config 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
 519 config IRQ_POLL
 520         bool "IRQ polling library"
 521         help
 522           Helper library to poll interrupt mitigation using polling.
 523
 524 config 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
 532 config 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 #
 545 config LIBFDT
 546         bool
 547
 548 config OID_REGISTRY
 549         tristate
 550         help
 551           Enable fast lookup object identifier registry.
 552
 553 config UCS2_STRING
 554         tristate
 555
 556 source "lib/fonts/Kconfig"
 557
 558 config 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
 565 config 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
 576 config ARCH_HAS_SG_CHAIN
 577         def_bool n
 578
 579 config ARCH_HAS_PMEM_API
 580         bool
 581
 582 config ARCH_HAS_UACCESS_FLUSHCACHE
 583         bool
 584
 585 config STACKDEPOT
 586         bool
 587         select STACKTRACE
 588
 589 config SBITMAP
 590         bool
 591
 592 config PARMAN
 593         tristate "parman" if COMPILE_TEST
 594
 595 config PRIME_NUMBERS
 596         tristate
 597
 598 config STRING_SELFTEST
 599         tristate "Test string functions"
 600
 601 endmenu
 602
 603 config GENERIC_ASHLDI3
 604         bool
 605
 606 config GENERIC_ASHRDI3
 607         bool
 608
 609 config GENERIC_LSHRDI3
 610         bool
 611
 612 config GENERIC_MULDI3
 613         bool
 614
 615 config GENERIC_CMPDI2
 616         bool
 617
 618 config GENERIC_UCMPDI2
 619         bool