add upper-32-bits macro

We keep on getting "right shift count >= width of type" warnings when doing
things like

	sector_t s;

	x = s >> 56;

because with CONFIG_LBD=n, s is only 32-bit.  Similar problems can occur with
dma_addr_t's.

So add a simple wrapper function which code can use to avoid this warning.
The above example would become

	x = upper_32_bits(s) >> 24;

The first user is in fact AFS.

Cc: James Bottomley <[email protected]>
Cc: "Cameron, Steve" <[email protected]>
Cc: "Miller, Mike (OS Dev)" <[email protected]>
Cc: Hisashi Hifumi <[email protected]>
Cc: Alan Cox <[email protected]>
Cc: David Howells <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

0 files changed, 0 insertions, 0 deletions