1. Rename saved_command_line into boot_command_line.
2. Set command_line as __initdata.
[akpm@osdl.org: move some declarations to the right place]
Signed-off-by: Alon Bar-Lev <alon.barlev@gmail.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Current implementation stores a static command-line buffer allocated to
COMMAND_LINE_SIZE size. Most architectures stores two copies of this buffer,
one for future reference and one for parameter parsing.
Current kernel command-line size for most architecture is much too small for
module parameters, video settings, initramfs paramters and much more. The
problem is that setting COMMAND_LINE_SIZE to a grater value, allocates static
buffers.
In order to allow a greater command-line size, these buffers should be
dynamically allocated or marked as init disposable buffers, so unused memory
can be released.
This patch renames the static saved_command_line variable into
boot_command_line adding __initdata attribute, so that it can be disposed
after initialization. This rename is required so applications that use
saved_command_line will not be affected by this change.
It reintroduces saved_command_line as dynamically allocated buffer to match
the data in boot_command_line.
It also mark secondary command-line buffer as __initdata, and copies it to
dynamically allocated static_command_line buffer components may hold reference
to it after initialization.
This patch is for linux-2.6.20-rc4-mm1 and is divided to target each
architecture. I could not check this in any architecture so please forgive me
if I got it wrong.
The per-architecture modification is very simple, use boot_command_line in
place of saved_command_line. The common code is the change into dynamic
command-line.
This patch:
1. Rename saved_command_line into boot_command_line, mark as init
disposable.
2. Add dynamic allocated saved_command_line.
3. Add dynamic allocated static_command_line.
4. During startup copy: boot_command_line into saved_command_line. arch
command_line into static_command_line.
5. Parse static_command_line and not arch command_line, so arch
command_line may be freed.
Signed-off-by: Alon Bar-Lev <alon.barlev@gmail.com>
Cc: Andi Kleen <ak@muc.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Ian Molton <spyro@f2s.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Kazumoto Kojima <kkojima@rr.iij4u.or.jp>
Cc: Richard Curnow <rc@rc0.org.uk>
Cc: William Lee Irwin III <wli@holomorphy.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Miles Bader <uclinux-v850@lsi.nec.co.jp>
Cc: Chris Zankel <chris@zankel.net>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Avoid expensive integer divide 3 times per CPU per tick.
A userspace test of this loop went from 26ns, down to 19ns on a G5; and
from 123ns down to 28ns on a P3.
(Also avoid a variable bit shift, as suggested by Alan. The effect
of this wasn't noticable on the CPUs I tested with).
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
sys_write() takes a local copy of f_pos and writes that back
into the struct file. It does this so that two concurrent write()
callers don't make a mess of f_pos, and of the file contents.
ecryptfs should be calling vfs_write(). That way we also get the fsnotify
notifications, which ecryptfs presently appears to have subverted.
Convert direct calls to f_op->write() into calls to vfs_write().
Signed-off-by: Michael Halcrow <mhalcrow@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Provide an option to provide a view of the encrypted files such that the
metadata is always in the header of the files, regardless of whether the
metadata is actually in the header or in the extended attribute. This mode of
operation is useful for applications like incremental backup utilities that do
not preserve the extended attributes when directly accessing the lower files.
With this option enabled, the files under the eCryptfs mount point will be
read-only.
Signed-off-by: Michael Halcrow <mhalcrow@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Generalize the metadata reading and writing mechanisms, with two targets for
now: metadata in file header and metadata in the user.ecryptfs xattr of the
lower file.
[akpm@osdl.org: printk warning fix]
[bunk@stusta.de: make some needlessly global code static]
Signed-off-by: Michael Halcrow <mhalcrow@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch set introduces the ability to store cryptographic metadata into an
lower file extended attribute rather than the lower file header region.
This patch set implements two new mount options:
ecryptfs_xattr_metadata
- When set, newly created files will have their cryptographic
metadata stored in the extended attribute region of the file rather
than the header.
When storing the data in the file header, there is a minimum of 8KB
reserved for the header information for each file, making each file at
least 12KB in size. This can take up a lot of extra disk space if the user
creates a lot of small files. By storing the data in the extended
attribute, each file will only occupy at least of 4KB of space.
As the eCryptfs metadata set becomes larger with new features such as
multi-key associations, most popular filesystems will not be able to store
all of the information in the xattr region in some cases due to space
constraints. However, the majority of users will only ever associate one
key per file, so most users will be okay with storing their data in the
xattr region.
This option should be used with caution. I want to emphasize that the
xattr must be maintained under all circumstances, or the file will be
rendered permanently unrecoverable. The last thing I want is for a user to
forget to set an xattr flag in a backup utility, only to later discover
that their backups are worthless.
ecryptfs_encrypted_view
- When set, this option causes eCryptfs to present applications a
view of encrypted files as if the cryptographic metadata were
stored in the file header, whether the metadata is actually stored
in the header or in the extended attributes.
No matter what eCryptfs winds up doing in the lower filesystem, I want
to preserve a baseline format compatibility for the encrypted files. As of
right now, the metadata may be in the file header or in an xattr. There is
no reason why the metadata could not be put in a separate file in future
versions.
Without the compatibility mode, backup utilities would have to know to
back up the metadata file along with the files. The semantics of eCryptfs
have always been that the lower files are self-contained units of encrypted
data, and the only additional information required to decrypt any given
eCryptfs file is the key. That is what has always been emphasized about
eCryptfs lower files, and that is what users expect. Providing the
encrypted view option will provide a way to userspace applications wherein
they can always get to the same old familiar eCryptfs encrypted files,
regardless of what eCryptfs winds up doing with the metadata behind the
scenes.
This patch:
Add extended attribute support to version bit vector, flags to indicate when
xattr or encrypted view modes are enabled, and support for the new mount
options.
Signed-off-by: Michael Halcrow <mhalcrow@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Public key support code. This reads and writes packets in the header that
contain public key encrypted file keys. It calls the messaging code in the
previous patch to send and receive encryption and decryption request
packets from the userspace daemon.
[akpm@osdl.org: cleab fix]
Signed-off-by: Michael Halcrow <mhalcrow@us.ibm.com>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Alon Bar-Lev
Nick Piggin
Michael Halcrow