diff options
Diffstat (limited to 'drivers/scsi')
| -rw-r--r-- | drivers/scsi/virtio_scsi.c | 141 |
1 files changed, 94 insertions, 47 deletions
diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c index facfc90ef00..9fc5e67a0ca 100644 --- a/drivers/scsi/virtio_scsi.c +++ b/drivers/scsi/virtio_scsi.c @@ -50,18 +50,24 @@ struct virtio_scsi_vq { struct virtqueue *vq; }; +/* Per-target queue state */ +struct virtio_scsi_target_state { + /* Protects sg. Lock hierarchy is tgt_lock -> vq_lock. */ + spinlock_t tgt_lock; + + /* For sglist construction when adding commands to the virtqueue. */ + struct scatterlist sg[]; +}; + /* Driver instance state */ struct virtio_scsi { - /* Protects sg[]. The lock hierarchy is sg_lock -> vq_lock. */ - spinlock_t sg_lock; - struct virtio_device *vdev; + struct virtio_scsi_vq ctrl_vq; struct virtio_scsi_vq event_vq; struct virtio_scsi_vq req_vq; - /* For sglist construction when adding commands to the virtqueue. */ - struct scatterlist sg[]; + struct virtio_scsi_target_state *tgt[]; }; static struct kmem_cache *virtscsi_cmd_cache; @@ -230,25 +236,17 @@ static void virtscsi_map_sgl(struct scatterlist *sg, unsigned int *p_idx, * @req_size : size of the request buffer * @resp_size : size of the response buffer * - * Called with vq_lock held. + * Called with tgt_lock held. */ -static void virtscsi_map_cmd(struct virtio_scsi *vscsi, +static void virtscsi_map_cmd(struct virtio_scsi_target_state *tgt, struct virtio_scsi_cmd *cmd, unsigned *out_num, unsigned *in_num, size_t req_size, size_t resp_size) { struct scsi_cmnd *sc = cmd->sc; - struct scatterlist *sg = vscsi->sg; + struct scatterlist *sg = tgt->sg; unsigned int idx = 0; - if (sc) { - struct Scsi_Host *shost = virtio_scsi_host(vscsi->vdev); - BUG_ON(scsi_sg_count(sc) > shost->sg_tablesize); - - /* TODO: check feature bit and fail if unsupported? */ - BUG_ON(sc->sc_data_direction == DMA_BIDIRECTIONAL); - } - /* Request header. */ sg_set_buf(&sg[idx++], &cmd->req, req_size); @@ -268,7 +266,8 @@ static void virtscsi_map_cmd(struct virtio_scsi *vscsi, *in_num = idx - *out_num; } -static int virtscsi_kick_cmd(struct virtio_scsi *vscsi, struct virtio_scsi_vq *vq, +static int virtscsi_kick_cmd(struct virtio_scsi_target_state *tgt, + struct virtio_scsi_vq *vq, struct virtio_scsi_cmd *cmd, size_t req_size, size_t resp_size, gfp_t gfp) { @@ -276,12 +275,12 @@ static int virtscsi_kick_cmd(struct virtio_scsi *vscsi, struct virtio_scsi_vq *v unsigned long flags; int ret; - spin_lock_irqsave(&vscsi->sg_lock, flags); - virtscsi_map_cmd(vscsi, cmd, &out_num, &in_num, req_size, resp_size); + spin_lock_irqsave(&tgt->tgt_lock, flags); + virtscsi_map_cmd(tgt, cmd, &out_num, &in_num, req_size, resp_size); spin_lock(&vq->vq_lock); - ret = virtqueue_add_buf(vq->vq, vscsi->sg, out_num, in_num, cmd, gfp); - spin_unlock(&vscsi->sg_lock); + ret = virtqueue_add_buf(vq->vq, tgt->sg, out_num, in_num, cmd, gfp); + spin_unlock(&tgt->tgt_lock); if (ret >= 0) ret = virtqueue_kick_prepare(vq->vq); @@ -295,9 +294,16 @@ static int virtscsi_kick_cmd(struct virtio_scsi *vscsi, struct virtio_scsi_vq *v static int virtscsi_queuecommand(struct Scsi_Host *sh, struct scsi_cmnd *sc) { struct virtio_scsi *vscsi = shost_priv(sh); + struct virtio_scsi_target_state *tgt = vscsi->tgt[sc->device->id]; struct virtio_scsi_cmd *cmd; int ret; + struct Scsi_Host *shost = virtio_scsi_host(vscsi->vdev); + BUG_ON(scsi_sg_count(sc) > shost->sg_tablesize); + + /* TODO: check feature bit and fail if unsupported? */ + BUG_ON(sc->sc_data_direction == DMA_BIDIRECTIONAL); + dev_dbg(&sc->device->sdev_gendev, "cmd %p CDB: %#02x\n", sc, sc->cmnd[0]); @@ -322,7 +328,7 @@ static int virtscsi_queuecommand(struct Scsi_Host *sh, struct scsi_cmnd *sc) BUG_ON(sc->cmd_len > VIRTIO_SCSI_CDB_SIZE); memcpy(cmd->req.cmd.cdb, sc->cmnd, sc->cmd_len); - if (virtscsi_kick_cmd(vscsi, &vscsi->req_vq, cmd, + if (virtscsi_kick_cmd(tgt, &vscsi->req_vq, cmd, sizeof cmd->req.cmd, sizeof cmd->resp.cmd, GFP_ATOMIC) >= 0) ret = 0; @@ -334,10 +340,11 @@ out: static int virtscsi_tmf(struct virtio_scsi *vscsi, struct virtio_scsi_cmd *cmd) { DECLARE_COMPLETION_ONSTACK(comp); + struct virtio_scsi_target_state *tgt = vscsi->tgt[cmd->sc->device->id]; int ret = FAILED; cmd->comp = ∁ - if (virtscsi_kick_cmd(vscsi, &vscsi->ctrl_vq, cmd, + if (virtscsi_kick_cmd(tgt, &vscsi->ctrl_vq, cmd, sizeof cmd->req.tmf, sizeof cmd->resp.tmf, GFP_NOIO) < 0) goto out; @@ -437,11 +444,49 @@ static void virtscsi_init_vq(struct virtio_scsi_vq *virtscsi_vq, virtscsi_vq->vq = vq; } +static struct virtio_scsi_target_state *virtscsi_alloc_tgt( + struct virtio_device *vdev, int sg_elems) +{ + struct virtio_scsi_target_state *tgt; + gfp_t gfp_mask = GFP_KERNEL; + + /* We need extra sg elements at head and tail. */ + tgt = kmalloc(sizeof(*tgt) + sizeof(tgt->sg[0]) * (sg_elems + 2), + gfp_mask); + + if (!tgt) + return NULL; + + spin_lock_init(&tgt->tgt_lock); + sg_init_table(tgt->sg, sg_elems + 2); + return tgt; +} + +static void virtscsi_remove_vqs(struct virtio_device *vdev) +{ + struct Scsi_Host *sh = virtio_scsi_host(vdev); + struct virtio_scsi *vscsi = shost_priv(sh); + u32 i, num_targets; + + /* Stop all the virtqueues. */ + vdev->config->reset(vdev); + + num_targets = sh->max_id; + for (i = 0; i < num_targets; i++) { + kfree(vscsi->tgt[i]); + vscsi->tgt[i] = NULL; + } + + vdev->config->del_vqs(vdev); +} + static int virtscsi_init(struct virtio_device *vdev, - struct virtio_scsi *vscsi) + struct virtio_scsi *vscsi, int num_targets) { int err; struct virtqueue *vqs[3]; + u32 i, sg_elems; + vq_callback_t *callbacks[] = { virtscsi_ctrl_done, virtscsi_event_done, @@ -464,7 +509,23 @@ static int virtscsi_init(struct virtio_device *vdev, virtscsi_config_set(vdev, cdb_size, VIRTIO_SCSI_CDB_SIZE); virtscsi_config_set(vdev, sense_size, VIRTIO_SCSI_SENSE_SIZE); - return 0; + + /* We need to know how many segments before we allocate. */ + sg_elems = virtscsi_config_get(vdev, seg_max) ?: 1; + + for (i = 0; i < num_targets; i++) { + vscsi->tgt[i] = virtscsi_alloc_tgt(vdev, sg_elems); + if (!vscsi->tgt[i]) { + err = -ENOMEM; + goto out; + } + } + err = 0; + +out: + if (err) + virtscsi_remove_vqs(vdev); + return err; } static int __devinit virtscsi_probe(struct virtio_device *vdev) @@ -472,31 +533,25 @@ static int __devinit virtscsi_probe(struct virtio_device *vdev) struct Scsi_Host *shost; struct virtio_scsi *vscsi; int err; - u32 sg_elems; + u32 sg_elems, num_targets; u32 cmd_per_lun; - /* We need to know how many segments before we allocate. - * We need an extra sg elements at head and tail. - */ - sg_elems = virtscsi_config_get(vdev, seg_max) ?: 1; - /* Allocate memory and link the structs together. */ + num_targets = virtscsi_config_get(vdev, max_target) + 1; shost = scsi_host_alloc(&virtscsi_host_template, - sizeof(*vscsi) + sizeof(vscsi->sg[0]) * (sg_elems + 2)); + sizeof(*vscsi) + + num_targets * sizeof(struct virtio_scsi_target_state)); if (!shost) return -ENOMEM; + sg_elems = virtscsi_config_get(vdev, seg_max) ?: 1; shost->sg_tablesize = sg_elems; vscsi = shost_priv(shost); vscsi->vdev = vdev; vdev->priv = shost; - /* Random initializations. */ - spin_lock_init(&vscsi->sg_lock); - sg_init_table(vscsi->sg, sg_elems + 2); - - err = virtscsi_init(vdev, vscsi); + err = virtscsi_init(vdev, vscsi, num_targets); if (err) goto virtscsi_init_failed; @@ -504,7 +559,7 @@ static int __devinit virtscsi_probe(struct virtio_device *vdev) shost->cmd_per_lun = min_t(u32, cmd_per_lun, shost->can_queue); shost->max_sectors = virtscsi_config_get(vdev, max_sectors) ?: 0xFFFF; shost->max_lun = virtscsi_config_get(vdev, max_lun) + 1; - shost->max_id = virtscsi_config_get(vdev, max_target) + 1; + shost->max_id = num_targets; shost->max_channel = 0; shost->max_cmd_len = VIRTIO_SCSI_CDB_SIZE; err = scsi_add_host(shost, &vdev->dev); @@ -522,14 +577,6 @@ virtscsi_init_failed: return err; } -static void virtscsi_remove_vqs(struct virtio_device *vdev) -{ - /* Stop all the virtqueues. */ - vdev->config->reset(vdev); - - vdev->config->del_vqs(vdev); -} - static void __devexit virtscsi_remove(struct virtio_device *vdev) { struct Scsi_Host *shost = virtio_scsi_host(vdev); @@ -552,7 +599,7 @@ static int virtscsi_restore(struct virtio_device *vdev) struct Scsi_Host *sh = virtio_scsi_host(vdev); struct virtio_scsi *vscsi = shost_priv(sh); - return virtscsi_init(vdev, vscsi); + return virtscsi_init(vdev, vscsi, sh->max_id); } #endif |