2 # Library configuration
8 menu "Library routines"
19 config GENERIC_STRNCPY_FROM_USER
22 config GENERIC_FIND_FIRST_BIT
25 config NO_GENERIC_PCI_IOPORT_MAP
28 config GENERIC_PCI_IOMAP
33 select GENERIC_PCI_IOMAP
40 tristate "CRC-CCITT functions"
42 This option is provided for the case where no in-kernel-tree
43 modules require CRC-CCITT functions, but a module built outside
44 the kernel tree does. Such modules that use library CRC-CCITT
45 functions require M here.
48 tristate "CRC16 functions"
50 This option is provided for the case where no in-kernel-tree
51 modules require CRC16 functions, but a module built outside
52 the kernel tree does. Such modules that use library CRC16
53 functions require M here.
56 tristate "CRC calculation for the T10 Data Integrity Field"
58 This option is only needed if a module that's not in the
59 kernel tree needs to calculate CRC checks for use with the
60 SCSI data integrity subsystem.
63 tristate "CRC ITU-T V.41 functions"
65 This option is provided for the case where no in-kernel-tree
66 modules require CRC ITU-T V.41 functions, but a module built outside
67 the kernel tree does. Such modules that use library CRC ITU-T V.41
68 functions require M here.
71 tristate "CRC32/CRC32c functions"
75 This option is provided for the case where no in-kernel-tree
76 modules require CRC32/CRC32c functions, but a module built outside
77 the kernel tree does. Such modules that use library CRC32/CRC32c
78 functions require M here.
81 bool "CRC32 perform self test on init"
85 This option enables the CRC32 library functions to perform a
86 self test on initialization. The self test computes crc32_le
87 and crc32_be over byte strings with random alignment and length
88 and computes the total elapsed time and number of bytes processed.
91 prompt "CRC32 implementation"
93 default CRC32_SLICEBY8
95 This option allows a kernel builder to override the default choice
96 of CRC32 algorithm. Choose the default ("slice by 8") unless you
97 know that you need one of the others.
100 bool "Slice by 8 bytes"
102 Calculate checksum 8 bytes at a time with a clever slicing algorithm.
103 This is the fastest algorithm, but comes with a 8KiB lookup table.
104 Most modern processors have enough cache to hold this table without
107 This is the default implementation choice. Choose this one unless
108 you have a good reason not to.
110 config CRC32_SLICEBY4
111 bool "Slice by 4 bytes"
113 Calculate checksum 4 bytes at a time with a clever slicing algorithm.
114 This is a bit slower than slice by 8, but has a smaller 4KiB lookup
117 Only choose this option if you know what you are doing.
120 bool "Sarwate's Algorithm (one byte at a time)"
122 Calculate checksum a byte at a time using Sarwate's algorithm. This
123 is not particularly fast, but has a small 256 byte lookup table.
125 Only choose this option if you know what you are doing.
128 bool "Classic Algorithm (one bit at a time)"
130 Calculate checksum one bit at a time. This is VERY slow, but has
131 no lookup table. This is provided as a debugging option.
133 Only choose this option if you are debugging crc32.
138 tristate "CRC7 functions"
140 This option is provided for the case where no in-kernel-tree
141 modules require CRC7 functions, but a module built outside
142 the kernel tree does. Such modules that use library CRC7
143 functions require M here.
146 tristate "CRC32c (Castagnoli, et al) Cyclic Redundancy-Check"
150 This option is provided for the case where no in-kernel-tree
151 modules require CRC32c functions, but a module built outside the
152 kernel tree does. Such modules that use library CRC32c functions
153 require M here. See Castagnoli93.
154 Module will be libcrc32c.
157 tristate "CRC8 function"
159 This option provides CRC8 function. Drivers may select this
160 when they need to do cyclic redundancy check according CRC8
161 algorithm. Module will be called crc8.
165 depends on AUDIT && !AUDIT_ARCH
169 # compression support is select'ed if needed
180 config LZO_DECOMPRESS
183 source "lib/xz/Kconfig"
186 # These all provide a common interface (hence the apparent duplication with
187 # ZLIB_INFLATE; DECOMPRESS_GZIP is just a wrapper.)
189 config DECOMPRESS_GZIP
193 config DECOMPRESS_BZIP2
196 config DECOMPRESS_LZMA
203 config DECOMPRESS_LZO
204 select LZO_DECOMPRESS
208 # Generic allocator support is selected if needed
210 config GENERIC_ALLOCATOR
214 # reed solomon support is select'ed if needed
219 config REED_SOLOMON_ENC8
222 config REED_SOLOMON_DEC8
225 config REED_SOLOMON_ENC16
228 config REED_SOLOMON_DEC16
232 # BCH support is selected if needed
237 config BCH_CONST_PARAMS
240 Drivers may select this option to force specific constant
241 values for parameters 'm' (Galois field order) and 't'
242 (error correction capability). Those specific values must
243 be set by declaring default values for symbols BCH_CONST_M
245 Doing so will enable extra compiler optimizations,
246 improving encoding and decoding performance up to 2x for
247 usual (m,t) values (typically such that m*t < 200).
248 When this option is selected, the BCH library supports
249 only a single (m,t) configuration. This is mainly useful
250 for NAND flash board drivers requiring known, fixed BCH
257 Constant value for Galois field order 'm'. If 'k' is the
258 number of data bits to protect, 'm' should be chosen such
259 that (k + m*t) <= 2**m - 1.
260 Drivers should declare a default value for this symbol if
261 they select option BCH_CONST_PARAMS.
266 Constant value for error correction capability in bits 't'.
267 Drivers should declare a default value for this symbol if
268 they select option BCH_CONST_PARAMS.
271 # Textsearch support is select'ed if needed
276 config TEXTSEARCH_KMP
282 config TEXTSEARCH_FSM
296 depends on HAS_IOMEM && !NO_IOPORT
304 config CHECK_SIGNATURE
307 config CPUMASK_OFFSTACK
308 bool "Force CPU masks off stack" if DEBUG_PER_CPU_MAPS
310 Use dynamic allocation for cpumask_var_t, instead of putting
311 them on the stack. This is a bit more expensive, but avoids
314 config DISABLE_OBSOLETE_CPUMASK_FUNCTIONS
315 bool "Disable obsolete cpumask functions" if DEBUG_PER_CPU_MAPS
316 depends on EXPERIMENTAL && BROKEN
326 # Netlink attribute parsing support is select'ed if needed
332 # Generic 64-bit atomic support is selected if needed
334 config GENERIC_ATOMIC64
341 bool "Averaging functions"
343 This option is provided for the case where no in-kernel-tree
344 modules require averaging functions, but a module built outside
345 the kernel tree does. Such modules that use library averaging
346 functions require Y here.
354 tristate "CORDIC algorithm"
356 This option provides an implementation of the CORDIC algorithm;
357 calculations are in fixed point. Module will be called cordic.
360 bool "JEDEC DDR data"
362 Data from JEDEC specs for DDR SDRAM memories,
363 particularly the AC timing parameters and addressing
364 information. This data is useful for drivers handling
365 DDR SDRAM controllers.
371 Multiprecision maths library from GnuPG.
372 It is used to implement RSA digital signature verification,
373 which is used by IMA/EVM digital signature extension.
379 Additional sources of multiprecision maths library from GnuPG.
380 This code is unnecessary for RSA digital signature verification,
381 but can be compiled if needed.
385 depends on KEYS && CRYPTO
389 Digital signature verification. Currently only RSA is supported.
390 Implementation is done using GnuPG MPI library