config UBIFS_FS tristate "UBIFS file system support" select CRC16 select CRC32 select CRYPTO if UBIFS_FS_ADVANCED_COMPR select CRYPTO if UBIFS_FS_LZO select CRYPTO if UBIFS_FS_ZLIB select CRYPTO if UBIFS_FS_XZ select CRYPTO_LZO if UBIFS_FS_LZO select CRYPTO_DEFLATE if UBIFS_FS_ZLIB select CRYPTO_XZ if UBIFS_FS_XZ depends on MTD_UBI help UBIFS is a file system for flash devices which works on top of UBI. config UBIFS_FS_ADVANCED_COMPR bool "Advanced compression options" depends on UBIFS_FS help This option allows to explicitly choose which compressions, if any, are enabled in UBIFS. Removing compressors means inability to read existing file systems. If unsure, say 'N'. config UBIFS_FS_LZO bool "LZO compression support" if UBIFS_FS_ADVANCED_COMPR depends on UBIFS_FS default y help LZO compressor is generally faster than zlib but compresses worse. Say 'Y' if unsure. config UBIFS_FS_ZLIB bool "ZLIB compression support" if UBIFS_FS_ADVANCED_COMPR depends on UBIFS_FS default y help Zlib compresses better than LZO but it is slower. Say 'Y' if unsure. config UBIFS_FS_XZ bool "XZ decompression support" if UBIFS_FS_ADVANCED_COMPR depends on UBIFS_FS default y help XZ compresses better the ZLIB but it is slower.. Say 'Y' if unsure. config UBIFS_ATIME_SUPPORT bool "Access time support" if UBIFS_FS depends on UBIFS_FS default n help Originally UBIFS did not support atime, because it looked like a bad idea due increased flash wear. This option adds atime support and it is disabled by default to preserve the old behavior. If you enable this option, UBIFS starts updating atime, which means that file-system read operations will cause writes (inode atime updates). This may affect file-system performance and increase flash device wear, so be careful. How often atime is updated depends on the selected strategy: strictatime is the "heavy", relatime is "lighter", etc. If unsure, say 'N'