vfs.git, part 1 - compat_ioctl fixes

This is basically Jann's patches from last week. I have _not_
included the stuff like switching i2c to ->compat_ioctl() into this one - those need more testing. Ideally I would like fs/compat_ioctl.c shrunk a lot, but that's a separate story. Please, pull from

git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs.git for-linus

Shortlog:
Al Viro (1):
compat_ioctl: don't pass fd around when not needed

Jann Horn (2):
compat_ioctl: don't look up the fd twice
compat_ioctl: don't call do_ioctl under set_fs(KERNEL_DS)

Diffstat:

 fs/compat_ioctl.c  | 253 +++++++++++++++++++++++++++++------------------------
 fs/internal.h      |   7 ++
 fs/ioctl.c         |   4 +-
 include/linux/fs.h |   2 -
 4 files changed, 146 insertions(+), 120 deletions(-)