block: add BlockLimits structure to BlockDriverState
this patch adds BlockLimits which introduces discard and write_zeroes
limits and alignment information to the BlockDriverState.
Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
diff --git a/include/block/block_int.h b/include/block/block_int.h
index d798208..95140b6 100644
--- a/include/block/block_int.h
+++ b/include/block/block_int.h
@@ -230,6 +230,20 @@
QLIST_ENTRY(BlockDriver) list;
};
+typedef struct BlockLimits {
+ /* maximum number of sectors that can be discarded at once */
+ int max_discard;
+
+ /* optimal alignment for discard requests in sectors */
+ int64_t discard_alignment;
+
+ /* maximum number of sectors that can zeroized at once */
+ int max_write_zeroes;
+
+ /* optimal alignment for write zeroes requests in sectors */
+ int64_t write_zeroes_alignment;
+} BlockLimits;
+
/*
* Note: the function bdrv_append() copies and swaps contents of
* BlockDriverStates, so if you add new fields to this struct, please
@@ -283,6 +297,9 @@
uint64_t total_time_ns[BDRV_MAX_IOTYPE];
uint64_t wr_highest_sector;
+ /* I/O Limits */
+ BlockLimits bl;
+
/* Whether the disk can expand beyond total_sectors */
int growable;
