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authorPeter Lieven <pl@kamp.de>2013-11-27 11:07:03 +0100
committerStefan Hajnoczi <stefanha@redhat.com>2013-12-05 11:45:24 +0100
commit1c0704a556dbb004a3b82791779760f418053951 (patch)
tree9f44874b5a0b32ced3500a48e1f2170b46998e2f /block/iscsi.c
parent049b09825fe479f4caa013ccde0ff87fc9d82856 (diff)
block/iscsi: set bdi->cluster_size
this patch aims to set bdi->cluster_size to the internal page size of the iscsi target so that enabled callers can align requests properly. Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Peter Lieven <pl@kamp.de> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Diffstat (limited to 'block/iscsi.c')
-rw-r--r--block/iscsi.c7
1 files changed, 7 insertions, 0 deletions
diff --git a/block/iscsi.c b/block/iscsi.c
index 93fee6d1df..75d6b875e4 100644
--- a/block/iscsi.c
+++ b/block/iscsi.c
@@ -1580,6 +1580,13 @@ static int iscsi_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
IscsiLun *iscsilun = bs->opaque;
bdi->unallocated_blocks_are_zero = !!iscsilun->lbprz;
bdi->can_write_zeroes_with_unmap = iscsilun->lbprz && iscsilun->lbp.lbpws;
+ /* Guess the internal cluster (page) size of the iscsi target by the means
+ * of opt_unmap_gran. Transfer the unmap granularity only if it has a
+ * reasonable size for bdi->cluster_size */
+ if (iscsilun->bl.opt_unmap_gran * iscsilun->block_size >= 64 * 1024 &&
+ iscsilun->bl.opt_unmap_gran * iscsilun->block_size <= 16 * 1024 * 1024) {
+ bdi->cluster_size = iscsilun->bl.opt_unmap_gran * iscsilun->block_size;
+ }
return 0;
}