libceph: get rid of zero_page_address
authorAlex Elder <elder@dreamhost.com>
Wed, 7 Mar 2012 17:40:08 +0000 (11:40 -0600)
committerAlex Elder <elder@dreamhost.com>
Thu, 22 Mar 2012 15:47:52 +0000 (10:47 -0500)
commit0cdf9e60189a87356a865a96dbafc2240af5c91d
tree832d6059c472d2d8777a9819a0ecb7b945167a1f
parente36b13cceb46136d849aeee06b4907ad3570ba78
libceph: get rid of zero_page_address

There's not a lot of benefit to zero_page_address, which basically
holds a mapping of the zero page through the life of the messenger
module.  Even with our own mapping, the sendpage interface where
it's used may need to kmap() it again.  It's almost certain to
be in low memory anyway.

So stop treating the zero page specially in write_partial_msg_pages()
and just get rid of zero_page_address entirely.

Signed-off-by: Alex Elder <elder@dreamhost.com>
Reviewed-by: Sage Weil <sage@newdream.net>
net/ceph/messenger.c