1ec8f24b7SThomas Gleixner# SPDX-License-Identifier: GPL-2.0-only 241810246SAlexey Dobriyanconfig ROMFS_FS 341810246SAlexey Dobriyan tristate "ROM file system support" 4f52fd5b7SDavid Howells depends on BLOCK || MTD 5a7f7f624SMasahiro Yamada help 641810246SAlexey Dobriyan This is a very small read-only file system mainly intended for 741810246SAlexey Dobriyan initial ram disks of installation disks, but it could be used for 841810246SAlexey Dobriyan other read-only media as well. Read 90c1bc6b8SMauro Carvalho Chehab <file:Documentation/filesystems/romfs.rst> for details. 1041810246SAlexey Dobriyan 1141810246SAlexey Dobriyan To compile this file system support as a module, choose M here: the 1241810246SAlexey Dobriyan module will be called romfs. Note that the file system of your 1341810246SAlexey Dobriyan root partition (the one containing the directory /) cannot be a 1441810246SAlexey Dobriyan module. 1541810246SAlexey Dobriyan 1641810246SAlexey Dobriyan If you don't know whether you need it, then you don't need it: 1741810246SAlexey Dobriyan answer N. 18da4458bdSDavid Howells 19f52fd5b7SDavid Howells# 20f52fd5b7SDavid Howells# Select the backing stores to be supported 21f52fd5b7SDavid Howells# 22f52fd5b7SDavid Howellschoice 23f52fd5b7SDavid Howells prompt "RomFS backing stores" 24f52fd5b7SDavid Howells depends on ROMFS_FS 25f52fd5b7SDavid Howells default ROMFS_BACKED_BY_BLOCK 26f52fd5b7SDavid Howells help 27f52fd5b7SDavid Howells Select the backing stores to be supported. 28f52fd5b7SDavid Howells 29f52fd5b7SDavid Howellsconfig ROMFS_BACKED_BY_BLOCK 30f52fd5b7SDavid Howells bool "Block device-backed ROM file system support" 31f52fd5b7SDavid Howells depends on BLOCK 32da4458bdSDavid Howells help 33da4458bdSDavid Howells This permits ROMFS to use block devices buffered through the page 34da4458bdSDavid Howells cache as the medium from which to retrieve data. It does not allow 35da4458bdSDavid Howells direct mapping of the medium. 36da4458bdSDavid Howells 37da4458bdSDavid Howells If unsure, answer Y. 38da4458bdSDavid Howells 39f52fd5b7SDavid Howellsconfig ROMFS_BACKED_BY_MTD 40da4458bdSDavid Howells bool "MTD-backed ROM file system support" 41da4458bdSDavid Howells depends on MTD=y || (ROMFS_FS=m && MTD) 42da4458bdSDavid Howells help 43da4458bdSDavid Howells This permits ROMFS to use MTD based devices directly, without the 44da4458bdSDavid Howells intercession of the block layer (which may have been disabled). It 45da4458bdSDavid Howells also allows direct mapping of MTD devices through romfs files under 46da4458bdSDavid Howells NOMMU conditions if the underlying device is directly addressable by 47da4458bdSDavid Howells the CPU. 48da4458bdSDavid Howells 49da4458bdSDavid Howells If unsure, answer Y. 50da4458bdSDavid Howells 51f52fd5b7SDavid Howellsconfig ROMFS_BACKED_BY_BOTH 52f52fd5b7SDavid Howells bool "Both the above" 53f52fd5b7SDavid Howells depends on BLOCK && (MTD=y || (ROMFS_FS=m && MTD)) 54f52fd5b7SDavid Howellsendchoice 55f52fd5b7SDavid Howells 56f52fd5b7SDavid Howells 57f52fd5b7SDavid Howellsconfig ROMFS_ON_BLOCK 58f52fd5b7SDavid Howells bool 59f52fd5b7SDavid Howells default y if ROMFS_BACKED_BY_BLOCK || ROMFS_BACKED_BY_BOTH 60f52fd5b7SDavid Howells 61f52fd5b7SDavid Howellsconfig ROMFS_ON_MTD 62f52fd5b7SDavid Howells bool 63f52fd5b7SDavid Howells default y if ROMFS_BACKED_BY_MTD || ROMFS_BACKED_BY_BOTH 64