kernel_optimize_test/fs/romfs/Kconfig
David Howells f52fd5b7fd NOMMU: Fix the RomFS Kconfig to ensure at least one backing store is selected
Fix the configuration of the RomFS to make sure that at least one 
backing store method is always selected.  This is done by rendering it 
down to a choice item that selects between Block, MTD and both.

This also works correctly in the case that CONFIG_MTD=m: MTD cannot be 
selected as a backing store unless CONFIG_ROMFS_FS is also 'm'.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2009-03-24 09:02:39 +00:00

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config ROMFS_FS
tristate "ROM file system support"
depends on BLOCK || MTD
---help---
This is a very small read-only file system mainly intended for
initial ram disks of installation disks, but it could be used for
other read-only media as well. Read
<file:Documentation/filesystems/romfs.txt> for details.
To compile this file system support as a module, choose M here: the
module will be called romfs. Note that the file system of your
root partition (the one containing the directory /) cannot be a
module.
If you don't know whether you need it, then you don't need it:
answer N.
#
# Select the backing stores to be supported
#
choice
prompt "RomFS backing stores"
depends on ROMFS_FS
default ROMFS_BACKED_BY_BLOCK
help
Select the backing stores to be supported.
config ROMFS_BACKED_BY_BLOCK
bool "Block device-backed ROM file system support"
depends on BLOCK
help
This permits ROMFS to use block devices buffered through the page
cache as the medium from which to retrieve data. It does not allow
direct mapping of the medium.
If unsure, answer Y.
config ROMFS_BACKED_BY_MTD
bool "MTD-backed ROM file system support"
depends on MTD=y || (ROMFS_FS=m && MTD)
help
This permits ROMFS to use MTD based devices directly, without the
intercession of the block layer (which may have been disabled). It
also allows direct mapping of MTD devices through romfs files under
NOMMU conditions if the underlying device is directly addressable by
the CPU.
If unsure, answer Y.
config ROMFS_BACKED_BY_BOTH
bool "Both the above"
depends on BLOCK && (MTD=y || (ROMFS_FS=m && MTD))
endchoice
config ROMFS_ON_BLOCK
bool
default y if ROMFS_BACKED_BY_BLOCK || ROMFS_BACKED_BY_BOTH
config ROMFS_ON_MTD
bool
default y if ROMFS_BACKED_BY_MTD || ROMFS_BACKED_BY_BOTH