diff options
| -rw-r--r-- | drivers/block/Kconfig | 11 | ||||
| -rw-r--r-- | drivers/block/virtio_blk.c | 143 |
2 files changed, 104 insertions, 50 deletions
diff --git a/drivers/block/Kconfig b/drivers/block/Kconfig index 7a4c787a5edf..f744de7a0f9b 100644 --- a/drivers/block/Kconfig +++ b/drivers/block/Kconfig @@ -500,11 +500,20 @@ config XEN_BLKDEV_BACKEND config VIRTIO_BLK tristate "Virtio block driver" depends on VIRTIO - select BLK_SCSI_REQUEST ---help--- This is the virtual block driver for virtio. It can be used with lguest or 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. + Your probably want to virtio-scsi instead. + config BLK_DEV_HD bool "Very old hard disk (MFM/RLL/IDE) driver" depends on HAVE_IDE diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c index 7c730e2f49c1..d9491bdd3ad3 100644 --- a/drivers/block/virtio_blk.c +++ b/drivers/block/virtio_blk.c @@ -52,11 +52,13 @@ struct virtio_blk { }; struct virtblk_req { - struct scsi_request sreq; /* for SCSI passthrough */ - struct virtio_blk_outhdr out_hdr; +#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; - u8 sense[SCSI_SENSE_BUFFERSIZE]; struct scatterlist sg[]; }; @@ -72,28 +74,88 @@ static inline int virtblk_result(struct virtblk_req *vbr) } } -static int __virtblk_add_req(struct virtqueue *vq, - struct virtblk_req *vbr, - struct scatterlist *data_sg, - bool have_data) +/* + * 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; - __virtio32 type = vbr->out_hdr.type & ~cpu_to_virtio32(vq->vdev, VIRTIO_BLK_T_OUT); 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_reques_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); + req->errors = 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; /* - * 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. + * Only allow the generic SCSI ioctls if the host can support it. */ - if (type == cpu_to_virtio32(vq->vdev, VIRTIO_BLK_T_SCSI_CMD)) { - sg_init_one(&cmd, vbr->sreq.cmd, vbr->sreq.cmd_len); - sgs[num_out++] = &cmd; - } + 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_reques_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) +{ + struct scatterlist hdr, status, *sgs[3]; + unsigned int num_out = 0, num_in = 0; + + sg_init_one(&hdr, &vbr->out_hdr, sizeof(vbr->out_hdr)); + sgs[num_out++] = &hdr; if (have_data) { if (vbr->out_hdr.type & cpu_to_virtio32(vq->vdev, VIRTIO_BLK_T_OUT)) @@ -102,13 +164,6 @@ static int __virtblk_add_req(struct virtqueue *vq, sgs[num_out + num_in++] = data_sg; } - if (type == cpu_to_virtio32(vq->vdev, VIRTIO_BLK_T_SCSI_CMD)) { - 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; @@ -118,17 +173,15 @@ static int __virtblk_add_req(struct virtqueue *vq, static inline void virtblk_request_done(struct request *req) { struct virtblk_req *vbr = blk_mq_rq_to_pdu(req); - struct virtio_blk *vblk = req->q->queuedata; int error = virtblk_result(vbr); - if (req->cmd_type == REQ_TYPE_BLOCK_PC) { - scsi_req(req)->resid_len = - virtio32_to_cpu(vblk->vdev, vbr->in_hdr.residual); - vbr->sreq.sense_len = - virtio32_to_cpu(vblk->vdev, vbr->in_hdr.sense_len); - req->errors = virtio32_to_cpu(vblk->vdev, vbr->in_hdr.errors); - } else if (req->cmd_type == REQ_TYPE_DRV_PRIV) { + switch (req->cmd_type) { + case REQ_TYPE_BLOCK_PC: + virtblk_scsi_reques_done(req); + break; + case REQ_TYPE_DRV_PRIV: req->errors = (error != 0); + break; } blk_mq_end_request(req, error); @@ -214,7 +267,10 @@ static int virtio_queue_rq(struct blk_mq_hw_ctx *hctx, } spin_lock_irqsave(&vblk->vqs[qid].lock, flags); - err = __virtblk_add_req(vblk->vqs[qid].vq, vbr, vbr->sg, num); + if (req->cmd_type == REQ_TYPE_BLOCK_PC) + 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); if (err) { virtqueue_kick(vblk->vqs[qid].vq); blk_mq_stop_hw_queue(hctx); @@ -259,22 +315,6 @@ out: return err; } -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); -} - /* We provide getgeo only to please some old bootloader/partitioning tools */ static int virtblk_getgeo(struct block_device *bd, struct hd_geometry *geo) { @@ -540,7 +580,9 @@ static int virtblk_init_request(void *data, struct request *rq, struct virtio_blk *vblk = 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; } @@ -824,7 +866,10 @@ 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, VIRTIO_BLK_F_SCSI, + 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, } |