zram: write incompressible pages to backing device
authorMinchan Kim <minchan@kernel.org>
Wed, 6 Sep 2017 23:20:03 +0000 (16:20 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Thu, 7 Sep 2017 00:27:25 +0000 (17:27 -0700)
commitdb8ffbd4e7634cc537c8d32e73e7ce0f06248645
treececb269b4da514c29db6671da523b57c824e56c7
parentae85a8075c5b025b9d503554ddc480a346a24536
zram: write incompressible pages to backing device

This patch enables write IO to transfer data to backing device.  For
that, it implements write_to_bdev function which creates new bio and
chaining with parent bio to make the parent bio asynchrnous.

For rw_page which don't have parent bio, it submit owned bio and handle
IO completion by zram_page_end_io.

Also, this patch defines new flag ZRAM_WB to mark written page for later
read IO.

[xieyisheng1@huawei.com: fix typo in comment]
Link: http://lkml.kernel.org/r/1502707447-6944-2-git-send-email-xieyisheng1@huawei.com
Link: http://lkml.kernel.org/r/1498459987-24562-8-git-send-email-minchan@kernel.org
Signed-off-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Yisheng Xie <xieyisheng1@huawei.com>
Cc: Juneho Choi <juno.choi@lge.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
drivers/block/zram/zram_drv.c
drivers/block/zram/zram_drv.h