From d54eaa5a0fde0a202e4e91f200f818edcef15bee Mon Sep 17 00:00:00 2001 From: Mike Snitzer Date: Fri, 21 Dec 2012 20:23:36 +0000 Subject: dm: prepare to support WRITE SAME Allow targets to opt in to WRITE SAME support by setting 'num_write_same_requests' in the dm_target structure. A dm device will only advertise WRITE SAME support if all its targets and all its underlying devices support it. Signed-off-by: Mike Snitzer Signed-off-by: Alasdair G Kergon --- include/linux/device-mapper.h | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'include') diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h index 38d27a10aa5d..d1f6cd8486f2 100644 --- a/include/linux/device-mapper.h +++ b/include/linux/device-mapper.h @@ -205,6 +205,11 @@ struct dm_target { */ unsigned num_discard_requests; + /* + * The number of WRITE SAME requests that will be submitted to the target. + */ + unsigned num_write_same_requests; + /* target specific data */ void *private; -- cgit v1.2.3