move fs/partitions to block/

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
fs: move code out of buffer.c

Move invalidate_bdev, block_sync_page into fs/block_dev.c.  Export
kill_bdev as well, so brd doesn't have to open code it.  Reduce
buffer_head.h requirement accordingly.

Removed a rather large comment from invalidate_bdev, as it looked a bit
obsolete to bother moving.  The small comment replacing it says enough.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Conflicts:
	fs/buffer.c
switch sys_mknodat(2) to umode_t

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
new helpers: kern_path_create/user_path_create

combination of kern_path_parent() and lookup_create().  Does *not*
expose struct nameidata to caller.  Syscalls converted to that...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Conflicts:
	fs/namei.c
switch ->mknod() to umode_t

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Conflicts:
	fs/cifs/cifsfs.h
	fs/xfs/xfs_iops.c
	include/linux/fs.h