mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-25 13:14:07 +08:00
6a108a14fa
The meaning of CONFIG_EMBEDDED has long since been obsoleted; the option is used to configure any non-standard kernel with a much larger scope than only small devices. This patch renames the option to CONFIG_EXPERT in init/Kconfig and fixes references to the option throughout the kernel. A new CONFIG_EMBEDDED option is added that automatically selects CONFIG_EXPERT when enabled and can be used in the future to isolate options that should only be considered for embedded systems (RISC architectures, SLOB, etc). Calling the option "EXPERT" more accurately represents its intention: only expert users who understand the impact of the configuration changes they are making should enable it. Reviewed-by: Ingo Molnar <mingo@elte.hu> Acked-by: David Woodhouse <david.woodhouse@intel.com> Signed-off-by: David Rientjes <rientjes@google.com> Cc: Greg KH <gregkh@suse.de> Cc: "David S. Miller" <davem@davemloft.net> Cc: Jens Axboe <axboe@kernel.dk> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Robin Holt <holt@sgi.com> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
169 lines
5.3 KiB
Plaintext
169 lines
5.3 KiB
Plaintext
#
|
|
# Configuration for initramfs
|
|
#
|
|
|
|
config INITRAMFS_SOURCE
|
|
string "Initramfs source file(s)"
|
|
default ""
|
|
help
|
|
This can be either a single cpio archive with a .cpio suffix or a
|
|
space-separated list of directories and files for building the
|
|
initramfs image. A cpio archive should contain a filesystem archive
|
|
to be used as an initramfs image. Directories should contain a
|
|
filesystem layout to be included in the initramfs image. Files
|
|
should contain entries according to the format described by the
|
|
"usr/gen_init_cpio" program in the kernel tree.
|
|
|
|
When multiple directories and files are specified then the
|
|
initramfs image will be the aggregate of all of them.
|
|
|
|
See <file:Documentation/early-userspace/README> for more details.
|
|
|
|
If you are not sure, leave it blank.
|
|
|
|
config INITRAMFS_ROOT_UID
|
|
int "User ID to map to 0 (user root)"
|
|
depends on INITRAMFS_SOURCE!=""
|
|
default "0"
|
|
help
|
|
This setting is only meaningful if the INITRAMFS_SOURCE is
|
|
contains a directory. Setting this user ID (UID) to something
|
|
other than "0" will cause all files owned by that UID to be
|
|
owned by user root in the initial ramdisk image.
|
|
|
|
If you are not sure, leave it set to "0".
|
|
|
|
config INITRAMFS_ROOT_GID
|
|
int "Group ID to map to 0 (group root)"
|
|
depends on INITRAMFS_SOURCE!=""
|
|
default "0"
|
|
help
|
|
This setting is only meaningful if the INITRAMFS_SOURCE is
|
|
contains a directory. Setting this group ID (GID) to something
|
|
other than "0" will cause all files owned by that GID to be
|
|
owned by group root in the initial ramdisk image.
|
|
|
|
If you are not sure, leave it set to "0".
|
|
|
|
config RD_GZIP
|
|
bool "Support initial ramdisks compressed using gzip" if EXPERT
|
|
default y
|
|
depends on BLK_DEV_INITRD
|
|
select DECOMPRESS_GZIP
|
|
help
|
|
Support loading of a gzip encoded initial ramdisk or cpio buffer.
|
|
If unsure, say Y.
|
|
|
|
config RD_BZIP2
|
|
bool "Support initial ramdisks compressed using bzip2" if EXPERT
|
|
default !EXPERT
|
|
depends on BLK_DEV_INITRD
|
|
select DECOMPRESS_BZIP2
|
|
help
|
|
Support loading of a bzip2 encoded initial ramdisk or cpio buffer
|
|
If unsure, say N.
|
|
|
|
config RD_LZMA
|
|
bool "Support initial ramdisks compressed using LZMA" if EXPERT
|
|
default !EXPERT
|
|
depends on BLK_DEV_INITRD
|
|
select DECOMPRESS_LZMA
|
|
help
|
|
Support loading of a LZMA encoded initial ramdisk or cpio buffer
|
|
If unsure, say N.
|
|
|
|
config RD_XZ
|
|
bool "Support initial ramdisks compressed using XZ" if EXPERT
|
|
default !EXPERT
|
|
depends on BLK_DEV_INITRD
|
|
select DECOMPRESS_XZ
|
|
help
|
|
Support loading of a XZ encoded initial ramdisk or cpio buffer.
|
|
If unsure, say N.
|
|
|
|
config RD_LZO
|
|
bool "Support initial ramdisks compressed using LZO" if EXPERT
|
|
default !EXPERT
|
|
depends on BLK_DEV_INITRD
|
|
select DECOMPRESS_LZO
|
|
help
|
|
Support loading of a LZO encoded initial ramdisk or cpio buffer
|
|
If unsure, say N.
|
|
|
|
choice
|
|
prompt "Built-in initramfs compression mode" if INITRAMFS_SOURCE!=""
|
|
help
|
|
This option decides by which algorithm the builtin initramfs
|
|
will be compressed. Several compression algorithms are
|
|
available, which differ in efficiency, compression and
|
|
decompression speed. Compression speed is only relevant
|
|
when building a kernel. Decompression speed is relevant at
|
|
each boot.
|
|
|
|
If you have any problems with bzip2 or LZMA compressed
|
|
initramfs, mail me (Alain Knaff) <alain@knaff.lu>.
|
|
|
|
High compression options are mostly useful for users who are
|
|
low on RAM, since it reduces the memory consumption during
|
|
boot.
|
|
|
|
If in doubt, select 'gzip'
|
|
|
|
config INITRAMFS_COMPRESSION_NONE
|
|
bool "None"
|
|
help
|
|
Do not compress the built-in initramfs at all. This may
|
|
sound wasteful in space, but, you should be aware that the
|
|
built-in initramfs will be compressed at a later stage
|
|
anyways along with the rest of the kernel, on those
|
|
architectures that support this.
|
|
However, not compressing the initramfs may lead to slightly
|
|
higher memory consumption during a short time at boot, while
|
|
both the cpio image and the unpacked filesystem image will
|
|
be present in memory simultaneously
|
|
|
|
config INITRAMFS_COMPRESSION_GZIP
|
|
bool "Gzip"
|
|
depends on RD_GZIP
|
|
help
|
|
The old and tried gzip compression. It provides a good balance
|
|
between compression ratio and decompression speed.
|
|
|
|
config INITRAMFS_COMPRESSION_BZIP2
|
|
bool "Bzip2"
|
|
depends on RD_BZIP2
|
|
help
|
|
Its compression ratio and speed is intermediate.
|
|
Decompression speed is slowest among the four. The initramfs
|
|
size is about 10% smaller with bzip2, in comparison to gzip.
|
|
Bzip2 uses a large amount of memory. For modern kernels you
|
|
will need at least 8MB RAM or more for booting.
|
|
|
|
config INITRAMFS_COMPRESSION_LZMA
|
|
bool "LZMA"
|
|
depends on RD_LZMA
|
|
help
|
|
The most recent compression algorithm.
|
|
Its ratio is best, decompression speed is between the other
|
|
three. Compression is slowest. The initramfs size is about 33%
|
|
smaller with LZMA in comparison to gzip.
|
|
|
|
config INITRAMFS_COMPRESSION_XZ
|
|
bool "XZ"
|
|
depends on RD_XZ
|
|
help
|
|
XZ uses the LZMA2 algorithm. The initramfs size is about 30%
|
|
smaller with XZ in comparison to gzip. Decompression speed
|
|
is better than that of bzip2 but worse than gzip and LZO.
|
|
Compression is slow.
|
|
|
|
config INITRAMFS_COMPRESSION_LZO
|
|
bool "LZO"
|
|
depends on RD_LZO
|
|
help
|
|
Its compression ratio is the poorest among the four. The kernel
|
|
size is about 10% bigger than gzip; however its speed
|
|
(both compression and decompression) is the fastest.
|
|
|
|
endchoice
|