1# SPDX-License-Identifier: GPL-2.0-only
2config ROMFS_FS
3	tristate "ROM file system support"
4	depends on BLOCK || MTD
5	help
6	  This is a very small read-only file system mainly intended for
7	  initial ram disks of installation disks, but it could be used for
8	  other read-only media as well.  Read
9	  <file:Documentation/filesystems/romfs.rst> for details.
10
11	  To compile this file system support as a module, choose M here: the
12	  module will be called romfs.  Note that the file system of your
13	  root partition (the one containing the directory /) cannot be a
14	  module.
15
16	  If you don't know whether you need it, then you don't need it:
17	  answer N.
18
19#
20# Select the backing stores to be supported
21#
22choice
23	prompt "RomFS backing stores"
24	depends on ROMFS_FS
25	default ROMFS_BACKED_BY_BLOCK
26	help
27	  Select the backing stores to be supported.
28
29config ROMFS_BACKED_BY_BLOCK
30	bool "Block device-backed ROM file system support"
31	depends on BLOCK
32	help
33	  This permits ROMFS to use block devices buffered through the page
34	  cache as the medium from which to retrieve data.  It does not allow
35	  direct mapping of the medium.
36
37	  If unsure, answer Y.
38
39config ROMFS_BACKED_BY_MTD
40	bool "MTD-backed ROM file system support"
41	depends on MTD=y || (ROMFS_FS=m && MTD)
42	help
43	  This permits ROMFS to use MTD based devices directly, without the
44	  intercession of the block layer (which may have been disabled).  It
45	  also allows direct mapping of MTD devices through romfs files under
46	  NOMMU conditions if the underlying device is directly addressable by
47	  the CPU.
48
49	  If unsure, answer Y.
50
51config ROMFS_BACKED_BY_BOTH
52	bool "Both the above"
53	depends on BLOCK && (MTD=y || (ROMFS_FS=m && MTD))
54endchoice
55
56
57config ROMFS_ON_BLOCK
58	bool
59	default y if ROMFS_BACKED_BY_BLOCK || ROMFS_BACKED_BY_BOTH
60
61config ROMFS_ON_MTD
62	bool
63	default y if ROMFS_BACKED_BY_MTD || ROMFS_BACKED_BY_BOTH
64