Commit Graph

19 Commits

Author SHA1 Message Date
Gustavo Zacarias
cfd1f70a10 fs/initramfs: fix initramfs support
On commit a24877586a TARGETS_ROOTFS was
introduced, however fs/initramfs/initramfs.mk was never updated, hence a
show-targets would be rootfs-initramfs with rootfs-cpio afterwards hence
never rebuilding the kernel with a proper cpio archive since TARGETS is
always before rootfs-* as stated in the commit description.

Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
2014-03-06 23:01:33 +01:00
Thomas De Schampheleire
8da745f04a Config.in files: unification of comments about dependency on Linux kernel
This patch lines up the comments of packages that need a Linux kernel to be
built by buildroot, to the format:
    foo needs a Linux kernel to be built

Signed-off-by: Thomas De Schampheleire <thomas.de.schampheleire@gmail.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
2013-12-15 16:24:36 +01:00
Jerzy Grzegorek
cd2ff4f637 package: remove the empty trailing lines
Signed-off-by: Jerzy Grzegorek <jerzy.grzegorek@trzebnica.net>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
2013-09-13 11:10:23 +02:00
Valentine Barshak
391c82efa1 linux: Do not force GZIP initramfs compression
Initramfs compression does not make much sense for the architectures
that support compressed kernel images because in this case the data
would be compressed twice. This will eventually result in a bigger
kernel image and time overhead when uncompressing it.
The only reason to use compressed initramfs is to reduce memory
usage when the kernel prepares rootfs, and both the unpacked
filesystem and initramfs.cpio are present in the memory.

Buildroot attempts to force GZIP compression for initramfs,
however it doesn't always work because initramfs compression mode
depends on RAM disk compression supported by the kernel.
Thus, CONFIG_INITRAMFS_COMPRESSION_GZIP depends on CONFIG_RD_GZIP.
If CONFIG_RD_GZIP is not set, setting GZIP initramfs compression
will have no effect.

Besides, the kernel also supports other compression methods,
like BZIP2, LZMA, XZ and LZO. Forcing the good old GZIP does not
really make much sense any more.

This removes initramfs compression settings from Buildroot,
so that the default value preset in the kernel config is used,
which is CONFIG_INITRAMFS_COMPRESSION_NONE.

If initramfs compression is still needed, it can be set
in the kernel config (using make linux-menuconfig)

Signed-off-by: Valentine Barshak <gvaxon@gmail.com>
Acked-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
2013-07-08 14:50:31 +02:00
Jerzy Grzegorek
086f333f39 Normalize separator size to 80
Signed-off-by: Jerzy Grzegorek <jerzy.grzegorek@trzebnica.net>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
2013-06-07 10:54:54 +02:00
Arnout Vandecappelle
7e61918f9d cpio/initramfs: clarify their use in the help text
Recent mails on the list show that it is not very clear how to create
an initial RAM fs with buildroot.  So make this more explicit in the
cpio and initramfs help texts.  Hopefully this will reduce the /init
debugging we have to do.

Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
2012-11-07 11:48:13 +01:00
Arnout Vandecappelle (Essensium/Mind)
13a3afc536 fs/initramfs: refactor with fs/cpio
An initramfs is in fact the same as a cpio archive, but embedded in
the kernel.  So instead of duplicating the cpio infrastructure,
we can simply build images/rootfs.cpio and link that into the
kernel.

Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
2011-09-27 22:46:00 +02:00
Thomas Petazzoni
10a130f91e initramfs/init: make sure that 0, 1, 2 fds are available
As the kernel doesn't automatically mount devtmpfs when an initramfs
is used, commit 424888e474 has
introduced a small wrapper script that mounts devtmpfs before starting
the real init.

Unfortunately, the problem is that in this case, the init process runs
without any 0, 1 and 2 file descriptors, so none of the
messages/errors printed by the various initialization scripts can be
seen. This is due to the fact the init process relies on 0, 1 and 2
being opened by the kernel before init is started. However, as
/dev/console isn't present on the filesystem at the time the kernel
tries to open the console to create the 0, 1 and 2 file descriptors,
the kernel fails on this and prints the famous "Warning: unable to
open an initial console".

The proposed workaround is to actually open 0, 1 and 2 to /dev/console
in the wrapper script, right after mounting the devtmpfs filesystem,
and before starting the real init. The "Warning" from the kernel is
still shown, but at least the messages from the init scripts are
visible.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
2011-08-04 21:52:21 +02:00
Peter Korsgaard
424888e474 initramfs: fix boot with dynamic /dev
Devtmpfs (which is used by devtmpfs/mdev/udev options) doesn't get
automounted by the kernel when an initramfs is used, causing boot
failures when a dynamic /dev is used.

Fix it by adding a pre-init script to mount devtmpfs before running init.

Reported-by: Arnout Vandecappelle <arnout@mind.be>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
2011-07-20 16:30:14 +02:00
Mike Frysinger
dde5b6830c initramfs: fix init symlink creation
The -e test will dereference the symlink, so if there is no /bin/init,
we will constantly try to create the symlink.  So rather than error on
subsequent runs when the link exists, use the force flag to ln.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Acked-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
2010-11-17 21:20:45 +01:00
Thomas Petazzoni
2e869a7c05 Remove INITRAMFS_TARGET variable
This used to be needed when the filesystem code was rewritten, but not
the Linux compilation code. Now that the Linux compilation code has
been rewritten, the mechanism to ensure that initramfs gets built
*before* the kernel so that it can be integrated is different, and
this INITRAMFS_TARGET variable is no longer used.

See f507921d39 for details.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
2010-11-04 19:26:27 +01:00
Simon Pasch
c4cdcc3680 initramfs: Don't overwrite $(TARGET_DIR)/init if it exists
Closes #2443

Allow use of custom init scripts.

Signed-off-by: Simon Pasch <fpasch@googlemail.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
2010-08-29 23:34:03 +02:00
Thomas Petazzoni
c2a44f158e initramfs: update help text
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
2010-06-26 07:44:16 +02:00
Thomas Petazzoni
93e8014709 initramfs: only show the option when a Linux kernel is being built
Closes #2119

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
2010-06-26 07:43:20 +02:00
Thomas Petazzoni
f507921d39 linux: add support for initramfs
In Buildroot, the kernel is built and installed *before* the root
filesystems are built. This allows the root filesystem to correctly
contain the kernel modules that have been installed.

However, in the initramfs case, the root filesystem is part of the
kernel. Therefore, the kernel should be built *after* the root
filesystem (which, in the initramfs case simply builds a text file
listing all files/directories/devices/symlinks that should be part of
the initramfs). However, this isn't possible as the initramfs text
file would lack all kernel modules.

So, the solution choosen here is to keep the normal order: kernel is
built before the root filesystem is generated, and to add a little
quirk to retrigger a kernel compilation after the root filesystem
generation.

To do so, we add a ROOTFS_$(FSTYPE)_POST_TARGETS variable to the
fs/common.mk infrastructure. This allows individual filesystems to set
a target name that we should depend on *after* generating the root
filesystem itself (contrary to normal ROOTFS_$(FSTYPE)_DEPENDENCIES,
on which we depend *before* generating the root filesystem).

The initramfs code in fs/initramfs/initramfs.mk uses this to add a
dependency on 'linux26-rebuild-with-initramfs'.

In linux/linux.mk, we do various things :

 * If BR2_TARGET_ROOTFS_INITRAMFS is enabled (i.e if initramfs is
   enabled as a root filesystem type), then we create an empty
   rootfs.initramfs file (remember that at this point, the root
   filesystem hasn't been generated) and we adjust the kernel
   configuration to include an initramfs. Of course, in the initial
   kernel build, this initramfs will be empty.

 * In the linux26-rebuild-with-initramfs target, we retrigger a
   compilation of the kernel image, after removing the initramfs in
   the kernel sources to make sure it gets properly rebuilt (we've
   experienced cases were modifying the rootfs.initramfs file wouldn't
   retrigger the generation of the initramfs at the kernel level).

This is fairly quirky, but initramfs really is a special case, so in
one way or another, we need a little quirk to solve its specialness.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
2010-06-22 21:20:28 +02:00
Will Wagner
4ddb427ef9 initramfs: fix init symlink
When initramfs was ported to the new fs structure the init symlink
macro was defined, but forgot to add it to PRE_GEN_HOOKS

Signed-off-by: Will Wagner <will_wagner@carallon.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
2010-04-20 16:54:50 +02:00
Will Wagner
102ca91d74 Repair initramfs dependancies after move to fs
The restructure for building root filesystems changed the target name
for the initramfs file, to build the file the trget is now
initramfs-root but the generated file is rootfs.initramfs

Signed-off-by: Will Wagner <will_wagner@carallon.com>
Acked-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
2010-04-20 00:02:36 +02:00
Will Wagner
a7e276bc3d initramfs: trivial fix following move to fs
Signed-off-by: Will Wagner <will_wagner@carallon.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
2010-04-15 13:50:37 +02:00
Thomas Petazzoni
0585241505 Move all filesystem generation code to fs/
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
2010-04-09 11:04:36 +02:00