[PATCH v3 2/2] virtio-scsi: add error handling

Paolo Bonzini
2011-12-19T12:03:48Z

This commit adds basic error handling to the virtio-scsi
HBA device. Task management functions are sent synchronously
via the control virtqueue.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
v2->v3: added mempool, used GFP_NOIO instead of GFP_ATOMIC,
formatting fixes

v1->v2: use scmd_printk

drivers/scsi/virtio_scsi.c | 75 +++++++++++++++++++++++++++++++++++++++++++-
1 files changed, 74 insertions(+), 1 deletions(-)

diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c
index cf8732f..35ab0ef 100644
--- a/drivers/scsi/virtio_scsi.c
+++ b/drivers/scsi/virtio_scsi.c
@@ -36,6 +36,7 @@ static void dbg(const char *fmt, ...)
/* Command queue element */
struct virtio_scsi_cmd {
struct scsi_cmnd *sc;
+ struct completion *comp;
union {
struct virtio_scsi_cmd_req cmd;
struct virtio_scsi_ctrl_tmf_req tmf;
@@ -172,11 +173,12 @@ static void virtscsi_req_done(struct virtqueue *vq)
virtscsi_vq_done(vq, virtscsi_complete_cmd);
};

-/* These are still stubs. */
static void virtscsi_complete_free(void *buf)
{
struct virtio_scsi_cmd *cmd = buf;

+ if (cmd->comp)
+ complete_all(cmd->comp);
mempool_free(cmd, virtscsi_cmd_pool);
}

@@ -306,12 +308,79 @@ out:
return ret;
}

+static int virtscsi_tmf(struct virtio_scsi *vscsi, struct virtio_scsi_cmd *cmd)
+{
+ DECLARE_COMPLETION_ONSTACK(comp);
+ int ret;
+
+ cmd->comp = &comp;
+ ret = virtscsi_kick_cmd(vscsi, vscsi->ctrl_vq, cmd);
+ if (ret < 0)
+ return FAILED;
+
+ wait_for_completion(&comp);
+ if (cmd->resp.tmf.response != VIRTIO_SCSI_S_OK &&
+ cmd->resp.tmf.response != VIRTIO_SCSI_S_FUNCTION_SUCCEEDED)
+ return FAILED;
+
+ return SUCCESS;
+}
+
+static int virtscsi_device_reset(struct scsi_cmnd *sc)
+{
+ struct virtio_scsi *vscsi = shost_priv(sc->device->host);
+ struct virtio_scsi_cmd *cmd;
+
+ sdev_printk(KERN_INFO, sc->device, "device reset\n");
+ cmd = mempool_alloc(virtscsi_cmd_pool, GFP_NOIO);
+ if (!cmd)
+ return FAILED;
+
+ memset(cmd, 0, sizeof(*cmd));
+ cmd->sc = sc;
+ cmd->req.tmf = (struct virtio_scsi_ctrl_tmf_req){
+ .type = VIRTIO_SCSI_T_TMF,
+ .subtype = VIRTIO_SCSI_T_TMF_LOGICAL_UNIT_RESET,
+ .lun[0] = 1,
+ .lun[1] = sc->device->id,
+ .lun[2] = (sc->device->lun >> 8) | 0x40,
+ .lun[3] = sc->device->lun & 0xff,
+ };
+ return virtscsi_tmf(vscsi, cmd);
+}
+
+static int virtscsi_abort(struct scsi_cmnd *sc)
+{
+ struct virtio_scsi *vscsi = shost_priv(sc->device->host);
+ struct virtio_scsi_cmd *cmd;
+
+ scmd_printk(KERN_INFO, sc, "abort\n");
+ cmd = mempool_alloc(virtscsi_cmd_pool, GFP_NOIO);
+ if (!cmd)
+ return FAILED;
+
+ memset(cmd, 0, sizeof(*cmd));
+ cmd->sc = sc;
+ cmd->req.tmf = (struct virtio_scsi_ctrl_tmf_req){
+ .type = VIRTIO_SCSI_T_TMF,
+ .subtype = VIRTIO_SCSI_T_TMF_ABORT_TASK,
+ .lun[0] = 1,
+ .lun[1] = sc->device->id,
+ .lun[2] = (sc->device->lun >> 8) | 0x40,
+ .lun[3] = sc->device->lun & 0xff,
+ .tag = (__u64)sc,
+ };
+ return virtscsi_tmf(vscsi, cmd);
+}
+
static struct scsi_host_template virtscsi_host_template = {
.module = THIS_MODULE,
.name = "Virtio SCSI HBA",
.proc_name = "virtio_scsi",
.queuecommand = virtscsi_queuecommand,
.this_id = -1,
+ .eh_abort_handler = virtscsi_abort,
+ .eh_device_reset_handler = virtscsi_device_reset,

.can_queue = 1024,
.dma_boundary = UINT_MAX,
--
1.7.7.1