linux/fs/ext4
Dr. Tilmann Bubeck 393d1d1d76 ext4: implementation of a new ioctl called EXT4_IOC_SWAP_BOOT
Add a new ioctl, EXT4_IOC_SWAP_BOOT which swaps i_blocks and
associated attributes (like i_blocks, i_size, i_flags, ...) from the
specified inode with inode EXT4_BOOT_LOADER_INO (#5). This is
typically used to store a boot loader in a secure part of the
filesystem, where it can't be changed by a normal user by accident.
The data blocks of the previous boot loader will be associated with
the given inode.

This usercode program is a simple example of the usage:

int main(int argc, char *argv[])
{
  int fd;
  int err;

  if ( argc != 2 ) {
    printf("usage: ext4-swap-boot-inode FILE-TO-SWAP\n");
    exit(1);
  }

  fd = open(argv[1], O_WRONLY);
  if ( fd < 0 ) {
    perror("open");
    exit(1);
  }

  err = ioctl(fd, EXT4_IOC_SWAP_BOOT);
  if ( err < 0 ) {
    perror("ioctl");
    exit(1);
  }

  close(fd);
  exit(0);
}

[ Modified by Theodore Ts'o to fix a number of bugs in the original code.]

Signed-off-by: Dr. Tilmann Bubeck <t.bubeck@reinform.de>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-04-08 12:54:05 -04:00
..
acl.c ext4: fix the number of credits needed for acl ops with inline data 2013-02-09 15:23:03 -05:00
acl.h fs: take the ACL checks to common code 2011-07-25 14:30:23 -04:00
balloc.c ext4: introduce ext4_get_group_number() 2013-04-03 23:32:34 -04:00
bitmap.c ext4: Checksum the block bitmap properly with bigalloc enabled 2012-10-22 00:34:32 -04:00
block_validity.c ext2/3/4: delete unneeded includes of module.h 2012-01-09 13:52:10 +01:00
dir.c Various bug fixes for ext4. The most important is a fix for the new 2013-03-02 19:33:21 -08:00
ext4_extents.h ext4: remove single extent cache 2013-02-18 00:31:07 -05:00
ext4_jbd2.c ext4: add might_sleep() annotations 2013-04-03 22:00:52 -04:00
ext4_jbd2.h ext4: fix journal callback list traversal 2013-04-03 22:08:52 -04:00
ext4.h ext4: implementation of a new ioctl called EXT4_IOC_SWAP_BOOT 2013-04-08 12:54:05 -04:00
extents_status.c ext4: update extent status tree after an extent is zeroed out 2013-03-10 21:13:05 -04:00
extents_status.h ext4: update extent status tree after an extent is zeroed out 2013-03-10 21:13:05 -04:00
extents.c ext4: try to prepend extent to the existing one 2013-04-03 23:33:28 -04:00
file.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2013-02-26 20:16:07 -08:00
fsync.c ext4/jbd2: don't wait (forever) for stale tid caused by wraparound 2013-04-03 22:02:52 -04:00
hash.c ext4: reduce one "if" comparison in ext4_dirhash() 2013-02-01 22:33:21 -05:00
ialloc.c ext4: use atomic64_t for the per-flexbg free_clusters count 2013-03-11 23:39:59 -04:00
indirect.c ext4: refactor truncate code 2013-04-03 12:47:17 -04:00
inline.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2013-02-26 20:16:07 -08:00
inode.c ext4: implementation of a new ioctl called EXT4_IOC_SWAP_BOOT 2013-04-08 12:54:05 -04:00
ioctl.c ext4: implementation of a new ioctl called EXT4_IOC_SWAP_BOOT 2013-04-08 12:54:05 -04:00
Kconfig ext4: fix configuration dependencies for ext4 ACLs and security labels 2013-01-06 23:38:44 -05:00
Makefile ext4: Remove CONFIG_EXT4_FS_XATTR 2012-12-10 16:30:43 -05:00
mballoc.c ext4: introduce ext4_get_group_number() 2013-04-03 23:32:34 -04:00
mballoc.h ext4: use module parameters instead of debugfs for mballoc_debug 2013-02-09 16:28:20 -05:00
migrate.c ext4: fix the number of credits needed for ext4_ext_migrate() 2013-02-09 12:50:27 -05:00
mmp.c ext4: use unlikely to improve the efficiency of the kernel 2013-01-12 16:28:47 -05:00
move_extent.c ext4: implementation of a new ioctl called EXT4_IOC_SWAP_BOOT 2013-04-08 12:54:05 -04:00
namei.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2013-02-26 20:16:07 -08:00
page-io.c ext4: fix ext4_evict_inode() racing against workqueue processing code 2013-03-20 09:39:42 -04:00
resize.c ext4: introduce ext4_get_group_number() 2013-04-03 23:32:34 -04:00
super.c ext4: make ext4_block_in_group() much more efficient 2013-04-03 22:12:52 -04:00
symlink.c ext4: Remove CONFIG_EXT4_FS_XATTR 2012-12-10 16:30:43 -05:00
truncate.h ext4: move common truncate functions to header file 2011-06-27 19:16:04 -04:00
xattr_security.c Merge branch 'for_linus' into for_linus_merged 2012-01-10 11:54:07 -05:00
xattr_trusted.c ext2/3/4: delete unneeded includes of module.h 2012-01-09 13:52:10 +01:00
xattr_user.c ext2/3/4: delete unneeded includes of module.h 2012-01-09 13:52:10 +01:00
xattr.c ext4: fix xattr block allocation/release with bigalloc 2013-02-18 12:12:07 -05:00
xattr.h ext4: fix the number of credits needed for acl ops with inline data 2013-02-09 15:23:03 -05:00