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authorMikulas Patocka <mpatocka@redhat.com>2012-07-27 18:08:03 +0400
committerAlasdair G Kergon <agk@redhat.com>2012-07-27 18:08:03 +0400
commit7acf0277cea0f2da89ffffcc9892bea23f618e63 (patch)
tree5f5c77f9ab0750826691d53a027cdcd786771fbb /include/linux/device-mapper.h
parent55f2b8bdb0c7387eb2dc645b9ecbe5d0faa6b54e (diff)
downloadlinux-7acf0277cea0f2da89ffffcc9892bea23f618e63.tar.xz
dm: introduce split_discard_requests
This patch introduces a new variable split_discard_requests. It can be set by targets so that discard requests are split on max_io_len boundaries. When split_discard_requests is not set, discard requests are only split on boundaries between targets, as was the case before this patch. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Diffstat (limited to 'include/linux/device-mapper.h')
-rw-r--r--include/linux/device-mapper.h6
1 files changed, 6 insertions, 0 deletions
diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h
index b19c1e189a68..8bdbbfce759a 100644
--- a/include/linux/device-mapper.h
+++ b/include/linux/device-mapper.h
@@ -218,6 +218,12 @@ struct dm_target {
unsigned discards_supported:1;
/*
+ * Set if the target required discard request to be split
+ * on max_io_len boundary.
+ */
+ unsigned split_discard_requests:1;
+
+ /*
* Set if this target does not return zeroes on discarded blocks.
*/
unsigned discard_zeroes_data_unsupported:1;