A pgoff_t is defined (by default) to have type (unsigned long). On
architectures such as i686 that's a 32-bit type. The ceph address
space code was attempting to produce 64 bit offsets by shifting a
page's index by PAGE_CACHE_SHIFT, but the result was not what was
desired because the shift occurred before the result got promoted
to 64 bits.
Fix this by converting all uses of page->index used in this way to
use the page_offset() macro, which ensures the 64-bit result has the
intended value.
This fixes http://tracker.newdream.net/issues/3112
Reported-by: Mohamed Pakkeer <pakkeer.mohideen@realimage.com>
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
6285bc2312