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| author | Paolo Bonzini <pbonzini@redhat.com> | 2013-11-22 13:39:51 +0100 |
|---|---|---|
| committer | Stefan Hajnoczi <stefanha@redhat.com> | 2013-12-03 15:26:49 +0100 |
| commit | cffb1ec600de83f693a23578fc2f344c1af9b96f (patch) | |
| tree | dc6c9e603941735a69cab5adecbeb9171a980e23 /block | |
| parent | 95de6d7078b029b73708059a17cef20f332adcb7 (diff) | |
| download | qemu-cffb1ec600de83f693a23578fc2f344c1af9b96f.tar.gz qemu-cffb1ec600de83f693a23578fc2f344c1af9b96f.tar.bz2 qemu-cffb1ec600de83f693a23578fc2f344c1af9b96f.zip | |
block drivers: expose requirement for write same alignment from formats
This will let misaligned but large requests use zero clusters. This
is important because the cluster size is not guest visible.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Diffstat (limited to 'block')
| -rw-r--r-- | block/qcow2.c | 1 | ||||
| -rw-r--r-- | block/qed.c | 1 | ||||
| -rw-r--r-- | block/vmdk.c | 4 |
3 files changed, 6 insertions, 0 deletions
diff --git a/block/qcow2.c b/block/qcow2.c index 41e454a2f1..19e037406c 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -718,6 +718,7 @@ static int qcow2_open(BlockDriverState *bs, QDict *options, int flags, } qemu_opts_del(opts); + bs->bl.write_zeroes_alignment = s->cluster_sectors; if (s->use_lazy_refcounts && s->qcow_version < 3) { error_setg(errp, "Lazy refcounts require a qcow2 image with at least " diff --git a/block/qed.c b/block/qed.c index 59516a5704..450a1fa2e9 100644 --- a/block/qed.c +++ b/block/qed.c @@ -495,6 +495,7 @@ static int bdrv_qed_open(BlockDriverState *bs, QDict *options, int flags, } } + bs->bl.write_zeroes_alignment = s->header.cluster_size >> BDRV_SECTOR_BITS; s->need_check_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, qed_need_check_timer_cb, s); diff --git a/block/vmdk.c b/block/vmdk.c index eb84f46a7b..0734bc200c 100644 --- a/block/vmdk.c +++ b/block/vmdk.c @@ -428,6 +428,10 @@ static int vmdk_add_extent(BlockDriverState *bs, extent->l2_size = l2_size; extent->cluster_sectors = flat ? sectors : cluster_sectors; + if (!flat) { + bs->bl.write_zeroes_alignment = + MAX(bs->bl.write_zeroes_alignment, cluster_sectors); + } if (s->num_extents > 1) { extent->end_sector = (*(extent - 1)).end_sector + extent->sectors; } else { |