On Thu, Dec 12, 2019 at 05:37:19PM +0100, Christoph Hellwig wrote:
> 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@xxxxxx>
OK I'll queue this.
Thanks!
> ---
> arch/powerpc/configs/guest.config | 1 -
> drivers/block/Kconfig | 10 ---
> drivers/block/virtio_blk.c | 115 +-----------------------------
> 3 files changed, 1 insertion(+), 125 deletions(-)
>
> diff --git a/arch/powerpc/configs/guest.config b/arch/powerpc/configs/guest.config
> index 8b8cd18ecd7c..209f58515d88 100644
> --- a/arch/powerpc/configs/guest.config
> +++ b/arch/powerpc/configs/guest.config
> @@ -1,5 +1,4 @@
> CONFIG_VIRTIO_BLK=y
> -CONFIG_VIRTIO_BLK_SCSI=y
> CONFIG_SCSI_VIRTIO=y
> CONFIG_VIRTIO_NET=y
> CONFIG_NET_FAILOVER=y
> diff --git a/drivers/block/Kconfig b/drivers/block/Kconfig
> index 1bb8ec575352..025b1b77b11a 100644
> --- a/drivers/block/Kconfig
> +++ b/drivers/block/Kconfig
> @@ -432,16 +432,6 @@ config VIRTIO_BLK
> This is the virtual block driver for virtio. It can be used with
> QEMU based VMMs (like KVM or Xen). Say Y or M.
>
> -config VIRTIO_BLK_SCSI
> - bool "SCSI passthrough request for the Virtio block driver"
> - depends on VIRTIO_BLK
> - select BLK_SCSI_REQUEST
> - ---help---
> - Enable support for SCSI passthrough (e.g. the SG_IO ioctl) on
> - virtio-blk devices. This is only supported for the legacy
> - virtio protocol and not enabled by default by any hypervisor.
> - You probably want to use virtio-scsi instead.
> -
> config BLK_DEV_RBD
> tristate "Rados block device (RBD)"
> depends on INET && BLOCK
> diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
> index 7ffd719d89de..54158766334b 100644
> --- a/drivers/block/virtio_blk.c
> +++ b/drivers/block/virtio_blk.c
> @@ -11,7 +11,6 @@
> #include <linux/virtio_blk.h>
> #include <linux/scatterlist.h>
> #include <linux/string_helpers.h>
> -#include <scsi/scsi_cmnd.h>
> #include <linux/idr.h>
> #include <linux/blk-mq.h>
> #include <linux/blk-mq-virtio.h>
> @@ -56,11 +55,6 @@ struct virtio_blk {
> };
>
> struct virtblk_req {
> -#ifdef CONFIG_VIRTIO_BLK_SCSI
> - struct scsi_request sreq; /* for SCSI passthrough, must be first */
> - u8 sense[SCSI_SENSE_BUFFERSIZE];
> - struct virtio_scsi_inhdr in_hdr;
> -#endif
> struct virtio_blk_outhdr out_hdr;
> u8 status;
> struct scatterlist sg[];
> @@ -78,80 +72,6 @@ static inline blk_status_t virtblk_result(struct virtblk_req *vbr)
> }
> }
>
> -/*
> - * If this is a packet command we need a couple of additional headers. Behind
> - * the normal outhdr we put a segment with the scsi command block, and before
> - * the normal inhdr we put the sense data and the inhdr with additional status
> - * information.
> - */
> -#ifdef CONFIG_VIRTIO_BLK_SCSI
> -static int virtblk_add_req_scsi(struct virtqueue *vq, struct virtblk_req *vbr,
> - struct scatterlist *data_sg, bool have_data)
> -{
> - struct scatterlist hdr, status, cmd, sense, inhdr, *sgs[6];
> - unsigned int num_out = 0, num_in = 0;
> -
> - sg_init_one(&hdr, &vbr->out_hdr, sizeof(vbr->out_hdr));
> - sgs[num_out++] = &hdr;
> - sg_init_one(&cmd, vbr->sreq.cmd, vbr->sreq.cmd_len);
> - sgs[num_out++] = &cmd;
> -
> - if (have_data) {
> - if (vbr->out_hdr.type & cpu_to_virtio32(vq->vdev, VIRTIO_BLK_T_OUT))
> - sgs[num_out++] = data_sg;
> - else
> - sgs[num_out + num_in++] = data_sg;
> - }
> -
> - sg_init_one(&sense, vbr->sense, SCSI_SENSE_BUFFERSIZE);
> - sgs[num_out + num_in++] = &sense;
> - sg_init_one(&inhdr, &vbr->in_hdr, sizeof(vbr->in_hdr));
> - sgs[num_out + num_in++] = &inhdr;
> - sg_init_one(&status, &vbr->status, sizeof(vbr->status));
> - sgs[num_out + num_in++] = &status;
> -
> - return virtqueue_add_sgs(vq, sgs, num_out, num_in, vbr, GFP_ATOMIC);
> -}
> -
> -static inline void virtblk_scsi_request_done(struct request *req)
> -{
> - struct virtblk_req *vbr = blk_mq_rq_to_pdu(req);
> - struct virtio_blk *vblk = req->q->queuedata;
> - struct scsi_request *sreq = &vbr->sreq;
> -
> - sreq->resid_len = virtio32_to_cpu(vblk->vdev, vbr->in_hdr.residual);
> - sreq->sense_len = virtio32_to_cpu(vblk->vdev, vbr->in_hdr.sense_len);
> - sreq->result = virtio32_to_cpu(vblk->vdev, vbr->in_hdr.errors);
> -}
> -
> -static int virtblk_ioctl(struct block_device *bdev, fmode_t mode,
> - unsigned int cmd, unsigned long data)
> -{
> - struct gendisk *disk = bdev->bd_disk;
> - struct virtio_blk *vblk = disk->private_data;
> -
> - /*
> - * Only allow the generic SCSI ioctls if the host can support it.
> - */
> - if (!virtio_has_feature(vblk->vdev, VIRTIO_BLK_F_SCSI))
> - return -ENOTTY;
> -
> - return scsi_cmd_blk_ioctl(bdev, mode, cmd,
> - (void __user *)data);
> -}
> -#else
> -static inline int virtblk_add_req_scsi(struct virtqueue *vq,
> - struct virtblk_req *vbr, struct scatterlist *data_sg,
> - bool have_data)
> -{
> - return -EIO;
> -}
> -static inline void virtblk_scsi_request_done(struct request *req)
> -{
> -}
> -#define virtblk_ioctl NULL
> -#endif /* CONFIG_VIRTIO_BLK_SCSI */
> -
> static int virtblk_add_req(struct virtqueue *vq, struct virtblk_req *vbr,
> struct scatterlist *data_sg, bool have_data)
> {
> @@ -216,13 +136,6 @@ static inline void virtblk_request_done(struct request *req)
> req->special_vec.bv_offset);
> }
>
> - switch (req_op(req)) {
> - case REQ_OP_SCSI_IN:
> - case REQ_OP_SCSI_OUT:
> - virtblk_scsi_request_done(req);
> - break;
> - }
> -
> blk_mq_end_request(req, virtblk_result(vbr));
> }
>
> @@ -299,10 +212,6 @@ static blk_status_t virtio_queue_rq(struct blk_mq_hw_ctx *hctx,
> type = VIRTIO_BLK_T_WRITE_ZEROES;
> unmap = !(req->cmd_flags & REQ_NOUNMAP);
> break;
> - case REQ_OP_SCSI_IN:
> - case REQ_OP_SCSI_OUT:
> - type = VIRTIO_BLK_T_SCSI_CMD;
> - break;
> case REQ_OP_DRV_IN:
> type = VIRTIO_BLK_T_GET_ID;
> break;
> @@ -333,10 +242,7 @@ static blk_status_t virtio_queue_rq(struct blk_mq_hw_ctx *hctx,
> }
>
> spin_lock_irqsave(&vblk->vqs[qid].lock, flags);
> - if (blk_rq_is_scsi(req))
> - err = virtblk_add_req_scsi(vblk->vqs[qid].vq, vbr, vbr->sg, num);
> - else
> - err = virtblk_add_req(vblk->vqs[qid].vq, vbr, vbr->sg, num);
> + err = virtblk_add_req(vblk->vqs[qid].vq, vbr, vbr->sg, num);
> if (err) {
> virtqueue_kick(vblk->vqs[qid].vq);
> blk_mq_stop_hw_queue(hctx);
> @@ -404,7 +310,6 @@ static int virtblk_getgeo(struct block_device *bd, struct hd_geometry *geo)
> }
>
> static const struct block_device_operations virtblk_fops = {
> - .ioctl = virtblk_ioctl,
> .owner = THIS_MODULE,
> .getgeo = virtblk_getgeo,
> };
> @@ -683,9 +588,6 @@ static int virtblk_init_request(struct blk_mq_tag_set *set, struct request *rq,
> struct virtio_blk *vblk = set->driver_data;
> struct virtblk_req *vbr = blk_mq_rq_to_pdu(rq);
>
> -#ifdef CONFIG_VIRTIO_BLK_SCSI
> - vbr->sreq.sense = vbr->sense;
> -#endif
> sg_init_table(vbr->sg, vblk->sg_elems);
> return 0;
> }
> @@ -698,23 +600,11 @@ static int virtblk_map_queues(struct blk_mq_tag_set *set)
> vblk->vdev, 0);
> }
>
> -#ifdef CONFIG_VIRTIO_BLK_SCSI
> -static void virtblk_initialize_rq(struct request *req)
> -{
> - struct virtblk_req *vbr = blk_mq_rq_to_pdu(req);
> -
> - scsi_req_init(&vbr->sreq);
> -}
> -#endif
> -
> static const struct blk_mq_ops virtio_mq_ops = {
> .queue_rq = virtio_queue_rq,
> .commit_rqs = virtio_commit_rqs,
> .complete = virtblk_request_done,
> .init_request = virtblk_init_request,
> -#ifdef CONFIG_VIRTIO_BLK_SCSI
> - .initialize_rq_fn = virtblk_initialize_rq,
> -#endif
> .map_queues = virtblk_map_queues,
> };
>
> @@ -991,9 +881,6 @@ static const struct virtio_device_id id_table[] = {
> static unsigned int features_legacy[] = {
> VIRTIO_BLK_F_SEG_MAX, VIRTIO_BLK_F_SIZE_MAX, VIRTIO_BLK_F_GEOMETRY,
> VIRTIO_BLK_F_RO, VIRTIO_BLK_F_BLK_SIZE,
> -#ifdef CONFIG_VIRTIO_BLK_SCSI
> - VIRTIO_BLK_F_SCSI,
> -#endif
> VIRTIO_BLK_F_FLUSH, VIRTIO_BLK_F_TOPOLOGY, VIRTIO_BLK_F_CONFIG_WCE,
> VIRTIO_BLK_F_MQ, VIRTIO_BLK_F_DISCARD, VIRTIO_BLK_F_WRITE_ZEROES,
> }
> --
> 2.20.1
