diff options
author | Wen Congyang <wency@cn.fujitsu.com> | 2015-09-08 11:28:32 +0800 |
---|---|---|
committer | Jeff Cody <jcody@redhat.com> | 2015-09-25 08:37:07 -0400 |
commit | 9568b511c9f91c3d21ea3e83426d4ee7168c98bb (patch) | |
tree | db4332c4539db54b69b314a47a7eb4c921ca7104 /block | |
parent | 4da65c80921139f3e0ff63f5ea20c5d9c778364f (diff) |
block: Introduce a new API bdrv_co_no_copy_on_readv()
In some cases, we need to disable copy-on-read, and just
read the data.
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Message-id: 1441682913-14320-2-git-send-email-wency@cn.fujitsu.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
Diffstat (limited to 'block')
-rw-r--r-- | block/io.c | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/block/io.c b/block/io.c index d4bc83b33b..94e18e6a9d 100644 --- a/block/io.c +++ b/block/io.c @@ -932,7 +932,8 @@ static int coroutine_fn bdrv_co_do_preadv(BlockDriverState *bs, return ret; } - if (bs->copy_on_read) { + /* Don't do copy-on-read if we read data before write operation */ + if (bs->copy_on_read && !(flags & BDRV_REQ_NO_COPY_ON_READ)) { flags |= BDRV_REQ_COPY_ON_READ; } @@ -1001,6 +1002,15 @@ int coroutine_fn bdrv_co_readv(BlockDriverState *bs, int64_t sector_num, return bdrv_co_do_readv(bs, sector_num, nb_sectors, qiov, 0); } +int coroutine_fn bdrv_co_no_copy_on_readv(BlockDriverState *bs, + int64_t sector_num, int nb_sectors, QEMUIOVector *qiov) +{ + trace_bdrv_co_no_copy_on_readv(bs, sector_num, nb_sectors); + + return bdrv_co_do_readv(bs, sector_num, nb_sectors, qiov, + BDRV_REQ_NO_COPY_ON_READ); +} + int coroutine_fn bdrv_co_copy_on_readv(BlockDriverState *bs, int64_t sector_num, int nb_sectors, QEMUIOVector *qiov) { |