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| author | Akihiko Odaki <akihiko.odaki@gmail.com> | 2021-02-25 09:12:39 +0900 |
|---|---|---|
| committer | Stefan Hajnoczi <stefanha@redhat.com> | 2021-03-15 09:48:53 +0000 |
| commit | fb0b154c801e3447e505de420195fb7038695941 (patch) | |
| tree | a060af2e30b44fddad72be77331c4dad8ca12b61 /hw | |
| parent | 6157b0e19721aadb4c7fdcfe57b2924af6144b14 (diff) | |
| download | qemu-fb0b154c801e3447e505de420195fb7038695941.zip qemu-fb0b154c801e3447e505de420195fb7038695941.tar.gz qemu-fb0b154c801e3447e505de420195fb7038695941.tar.bz2 | |
virtio-blk: Respect discard granularity
Report the configured granularity for discard operation to the
guest. If this is not set use the block size.
Since until now we have ignored the configured discard granularity
and always reported the block size, let's add
'report-discard-granularity' property and disable it for older
machine types to avoid migration issues.
Signed-off-by: Akihiko Odaki <akihiko.odaki@gmail.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20210225001239.47046-1-akihiko.odaki@gmail.com>
Diffstat (limited to 'hw')
| -rw-r--r-- | hw/block/virtio-blk.c | 8 | ||||
| -rw-r--r-- | hw/core/machine.c | 1 |
2 files changed, 8 insertions, 1 deletions
diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c index 3d2072c..d28979e 100644 --- a/hw/block/virtio-blk.c +++ b/hw/block/virtio-blk.c @@ -962,10 +962,14 @@ static void virtio_blk_update_config(VirtIODevice *vdev, uint8_t *config) blkcfg.wce = blk_enable_write_cache(s->blk); virtio_stw_p(vdev, &blkcfg.num_queues, s->conf.num_queues); if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_DISCARD)) { + uint32_t discard_granularity = conf->discard_granularity; + if (discard_granularity == -1 || !s->conf.report_discard_granularity) { + discard_granularity = blk_size; + } virtio_stl_p(vdev, &blkcfg.max_discard_sectors, s->conf.max_discard_sectors); virtio_stl_p(vdev, &blkcfg.discard_sector_alignment, - blk_size >> BDRV_SECTOR_BITS); + discard_granularity >> BDRV_SECTOR_BITS); /* * We support only one segment per request since multiple segments * are not widely used and there are no userspace APIs that allow @@ -1299,6 +1303,8 @@ static Property virtio_blk_properties[] = { IOThread *), DEFINE_PROP_BIT64("discard", VirtIOBlock, host_features, VIRTIO_BLK_F_DISCARD, true), + DEFINE_PROP_BOOL("report-discard-granularity", VirtIOBlock, + conf.report_discard_granularity, true), DEFINE_PROP_BIT64("write-zeroes", VirtIOBlock, host_features, VIRTIO_BLK_F_WRITE_ZEROES, true), DEFINE_PROP_UINT32("max-discard-sectors", VirtIOBlock, diff --git a/hw/core/machine.c b/hw/core/machine.c index 4386f57..4c1a4a4 100644 --- a/hw/core/machine.c +++ b/hw/core/machine.c @@ -39,6 +39,7 @@ GlobalProperty hw_compat_5_2[] = { { "ICH9-LPC", "smm-compat", "on"}, { "PIIX4_PM", "smm-compat", "on"}, + { "virtio-blk-device", "report-discard-granularity", "off" }, }; const size_t hw_compat_5_2_len = G_N_ELEMENTS(hw_compat_5_2); |