md: prepare for managing resync I/O pages in clean way
authorMing Lei <tom.leiming@gmail.com>
Thu, 16 Mar 2017 16:12:24 +0000 (00:12 +0800)
committerShaohua Li <shli@fb.com>
Fri, 24 Mar 2017 17:41:36 +0000 (10:41 -0700)
commit513e2faa0138462ce014e1b0e226ca45c83bc6c1
treeac65dbf0f670f5e5f5fe807ee055f6bd559c77ac
parentd8e29fbc3bed181f2653fb89ac8c34e40db39c30
md: prepare for managing resync I/O pages in clean way

Now resync I/O use bio's bec table to manage pages,
this way is very hacky, and may not work any more
once multipage bvec is introduced.

So introduce helpers and new data structure for
managing resync I/O pages more cleanly.

Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Shaohua Li <shli@fb.com>
drivers/md/md.h