similar to: [PATCH v4 13/42] virtio_blk: v1.0 support

Based on patch by Cornelia Huck. Note: for consistency, and to avoid sparse errors, convert all fields, even those no longer in use for virtio v1.0. Reviewed-by: Thomas Huth <thuth at linux.vnet.ibm.com> Reviewed-by: David Hildenbrand <dahi at linux.vnet.ibm.com> Signed-off-by: Cornelia Huck <cornelia.huck at de.ibm.com> Signed-off-by: Michael S. Tsirkin <mst at

Based on patch by Cornelia Huck. Note: for consistency, and to avoid sparse errors, convert all fields, even those no longer in use for virtio v1.0. Reviewed-by: Thomas Huth <thuth at linux.vnet.ibm.com> Reviewed-by: David Hildenbrand <dahi at linux.vnet.ibm.com> Signed-off-by: Cornelia Huck <cornelia.huck at de.ibm.com> Signed-off-by: Michael S. Tsirkin <mst at

Based on patch by Cornelia Huck. Note: for consistency, and to avoid sparse errors, convert all fields, even those no longer in use for virtio v1.0. Signed-off-by: Cornelia Huck <cornelia.huck at de.ibm.com> Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- include/uapi/linux/virtio_blk.h | 15 ++++----- drivers/block/virtio_blk.c | 70

Based on patch by Cornelia Huck. Note: for consistency, and to avoid sparse errors, convert all fields, even those no longer in use for virtio v1.0. Signed-off-by: Cornelia Huck <cornelia.huck at de.ibm.com> Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- include/uapi/linux/virtio_blk.h | 15 ++++----- drivers/block/virtio_blk.c | 70

Based on patch by Cornelia Huck. Note: for consistency, and to avoid sparse errors, convert all fields, even those no longer in use for virtio v1.0. Signed-off-by: Cornelia Huck <cornelia.huck at de.ibm.com> Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- include/uapi/linux/virtio_blk.h | 15 ++++----- drivers/block/virtio_blk.c | 70

Based on patch by Cornelia Huck. Note: for consistency, and to avoid sparse errors, convert all fields, even those no longer in use for virtio v1.0. Signed-off-by: Cornelia Huck <cornelia.huck at de.ibm.com> Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- include/uapi/linux/virtio_blk.h | 15 ++++----- drivers/block/virtio_blk.c | 70

Based on patch by Cornelia Huck. Note: for consistency, and to avoid sparse errors, convert all fields, even those no longer in use for virtio v1.0. Signed-off-by: Cornelia Huck <cornelia.huck at de.ibm.com> Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- include/uapi/linux/virtio_blk.h | 15 ++++----- drivers/block/virtio_blk.c | 70

Based on patch by Cornelia Huck. Note: for consistency, and to avoid sparse errors, convert all fields, even those no longer in use for virtio v1.0. Signed-off-by: Cornelia Huck <cornelia.huck at de.ibm.com> Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- include/uapi/linux/virtio_blk.h | 15 ++++----- drivers/block/virtio_blk.c | 70

Based on patch by Cornelia Huck. Note: for consistency, and to avoid sparse errors, convert all fields, even those no longer in use for virtio v1.0. Reviewed-by: Thomas Huth <thuth at linux.vnet.ibm.com> Reviewed-by: David Hildenbrand <dahi at linux.vnet.ibm.com> Signed-off-by: Cornelia Huck <cornelia.huck at de.ibm.com> Signed-off-by: Michael S. Tsirkin <mst at

Based on patch by Cornelia Huck. Note: for consistency, and to avoid sparse errors, convert all fields, even those no longer in use for virtio v1.0. Reviewed-by: Thomas Huth <thuth at linux.vnet.ibm.com> Reviewed-by: David Hildenbrand <dahi at linux.vnet.ibm.com> Signed-off-by: Cornelia Huck <cornelia.huck at de.ibm.com> Signed-off-by: Michael S. Tsirkin <mst at

Based on patch by Cornelia Huck. Note: for consistency, and to avoid sparse errors, convert all fields, even those no longer in use for virtio v1.0. Signed-off-by: Cornelia Huck <cornelia.huck at de.ibm.com> Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- include/uapi/linux/virtio_blk.h | 15 ++++----- drivers/block/virtio_blk.c | 70

Based on patch by Cornelia Huck. Note: for consistency, and to avoid sparse errors, convert all fields, even those no longer in use for virtio v1.0. Signed-off-by: Cornelia Huck <cornelia.huck at de.ibm.com> Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- include/uapi/linux/virtio_blk.h | 15 ++++----- drivers/block/virtio_blk.c | 70

On Tue, Mar 28, 2017 at 04:39:25PM +0800, Changpeng Liu wrote: > Currently virtio-blk driver does not provide discard feature flag, so the > filesystems which built on top of the block device will not send discard > command. This is okay for HDD backend, but it will impact the performance > for SSD backend. > > Add a feature flag VIRTIO_BLK_F_DISCARD and command

> -----Original Message----- > From: Stefan Hajnoczi [mailto:stefanha at gmail.com] > Sent: Tuesday, March 28, 2017 4:20 AM > To: Liu, Changpeng <changpeng.liu at intel.com> > Cc: virtio-dev at lists.oasis-open.org; virtualization at lists.linux-foundation.org; linux- > kernel at vger.kernel.org; hch at lst.de; qemu-devel at nongnu.org > Subject: Re: [PATCH] virtio-blk:

> -----Original Message----- > From: Stefan Hajnoczi [mailto:stefanha at gmail.com] > Sent: Tuesday, March 28, 2017 4:20 AM > To: Liu, Changpeng <changpeng.liu at intel.com> > Cc: virtio-dev at lists.oasis-open.org; virtualization at lists.linux-foundation.org; linux- > kernel at vger.kernel.org; hch at lst.de; qemu-devel at nongnu.org > Subject: Re: [PATCH] virtio-blk:

Currently virtio-blk driver does not provide discard feature flag, so the filesystems which built on top of the block device will not send discard command. This is okay for HDD backend, but it will impact the performance for SSD backend. Add a feature flag VIRTIO_BLK_F_DISCARD and command VIRTIO_BLK_T_DISCARD to extend exist virtio-blk protocol. virtio-blk protocol uses a single 8 bytes

Currently virtio-blk driver does not provide discard feature flag, so the filesystems which built on top of the block device will not send discard command. This is okay for HDD backend, but it will impact the performance for SSD backend. Add a feature flag VIRTIO_BLK_F_DISCARD and command VIRTIO_BLK_T_DISCARD to extend exist virtio-blk protocol. virtio-blk protocol uses a single 8 bytes

This is fairly simple: we create a request pointing at the 1k kmalloc, then just change the type so our do_req() knows to mark it as a GET_ID for the server. Seems to work here; the only issue is that the error didn't get passed back from __blk_end_request_all to blk_execute_rq, so we set ->errors to 1 on error. Signed-off-by: Rusty Russell <rusty at rustcorp.com.au> Cc: Jens Axboe

This is fairly simple: we create a request pointing at the 1k kmalloc, then just change the type so our do_req() knows to mark it as a GET_ID for the server. Seems to work here; the only issue is that the error didn't get passed back from __blk_end_request_all to blk_execute_rq, so we set ->errors to 1 on error. Signed-off-by: Rusty Russell <rusty at rustcorp.com.au> Cc: Jens Axboe

Since the need for a special flag to support SCSI passthrough on a block device was added in May 2017 the SCSI passthrough support in virtio-blk has been disabled. It has always been a bad idea (just ask the original author..) and we have virtio-scsi for proper passthrough. The feature also never made it into the virtio 1.0 or later specifications. Signed-off-by: Christoph Hellwig <hch at